A transmission apparatus, connected via a hybrid circuit to a line, such as a modulator-demodulator which can perform stable echo cancellation, whether the level of the far-end echo is high or not, provided with a transmission unit which generates a transmission signal to be transmitted to the line via the hybrid circuit, a reception unit which receives the reception signal supplied from the line via the hybrid circuit, and a superimposing means for superimposing the reception signal applied to the hybrid circuit onto the transmission signal. The transmission signal onto which the reception signal is superimposed by the superimposing means is transmitted to the line via the hybrid circuit.

1. Field of the Invention
The present invention relates to a transmission apparatus, more particularly relates to a transmission apparatus having an echo cancellation facility.
In a modulator-demodulator for performing for example two-wire full-duplex communication, the transmission signal and the reception signal are separated by using a hybrid circuit. In this case, there arises a problem in that the transmission side signal ends up wrapping around the reception side via the hybrid circuit. For this reason, the conventional practice has been to improve the S/N ratio of the reception signal by performing echo cancellation to remove the wrapped around transmission signal from the reception signal.
The present invention will be explained below taking as an example a modulator-demodulator (modem), but it is also possible to apply the present invention to other types of transmission apparatuses.
2. Description of the Related Art
As will be explained in detail later by using the drawings, in the conventional echo cancellation methods, there is the possibility of occurrence of the following problems--particularly concerning far-end echo.
First, there is the case where the far-end echo level is small. In this case, there arises the following problem. An echo generated from the hybrid circuit in a telephone office far away from the transmission side modem is subjected to analog/digital conversion by an A/D converter in the same telephone office and transmitted to a four-wire line.
In the A/D converter, the output signal exhibits a relatively good linearity in a case where the level of the input signal is high, but in a case where the level of the input signal is low, when performing analog/digital conversion, an undesired nonlinear region of the A/D converter is used, where the linearity has been degraded. For this reason, distortion is caused in the signal output from the A/D converter in the telephone office.
On the other hand, the echo estimation for the echo cancellation is carried out based on the signal transmitted from a modulation unit in the local modem, therefore, basically, echo cancellation cannot be carried out with respect to a signal different from the signal transmitted from the local modem.
Due to the occurrence of the above distortion of the signal, however, it is not fully possible to perform echo cancellation when finding the difference between the signal output from the modulation unit in the local modem and the echo component contained in the signal received from the telephone office. The far-end echo component remains in that reception signal as it is. For this reason, as a result, the S/N ratio of the reception signal is deteriorated, and thus the possibility of occurrence of data error becomes higher where demodulation is carried out.
Second, there can be mentioned a case where the level of the far-end echo is too large. In this case, since the echo component contained in the reception signal supplied from a distant telephone office via a near telephone office to the local modem is too large, even if echo cancellation is carried out in response to the signal from the modulation unit in this modem, sufficient echo cancellation cannot be carried out and the echo component remains in the above reception signal. In this case as well, the S/N ratio of the reception signal is deteriorated, and a data error is caused in the result of demodulation.
In this way, when cancelling a far-end echo, the conventional apparatuses have a problem in that the echo could not be sufficiently cancelled if the level thereof is either too small or too large.

Transmission apparatus having echo cancellation facility


A saddle coupling and saddle base assembly is provided for use with power hand tools. The assembly is mounted atop a variably-adjustable stand for drilling holes or inserting fasteners into concrete ceilings, drywall ceilings or other overhead surfaces. The assembly comprises a saddle base and a saddle coupling that is removably attachable to the saddle base. The saddle coupling is configured to attach a single power hand tool or a plurality of power hand tools to the coupling. A plurality of like-configured saddle couplings can be attached to different power hand tools to allow the user to quickly and easily remove one saddle coupling and power hand tool and replace it for another. A spring-loaded locking feature is included in the assembly as a primary securement means for the assembly. A secondary securement means is also provided in the event of a failure of the primary means.

There are many applications where it is necessary to drill, nail or cut into an overhead surface, such as a concrete ceiling or a drywall ceiling. Such overhead surfaces can vary in their height from the floor. For example, before installing fasteners into concrete ceilings for overhead surfaces, it is usually necessary to first drill holes. Such holes are typically drilled using a hand-held power drill. In most applications, many such holes must be drilled within a single area. This means repetitive use and repositioning of the drill by the user. This repetitive overhead drilling creates a great deal of physical strain for a worker because, not only must the worker support the weight of the drill, but the worker must apply upwardly drilling force as well.
A fundamental problem with this type of work is reaching the overhead surface in the first place. In order to do that, the worker must typically construct scaffolding or ascend a ladder or other elevating device to drill each hole. For taller ceilings, a ladder may not reach or, because obstacles may not be able to be placed directly under the surface to be drilled or close enough to the drilling surface, the worker must dangerously overextend to drill the holes. In addition, standing on a ladder or other elevating device places the worker in close proximity to the dust and debris associated with the drilling of overhead concrete or other surfaces.
Stands for supporting a drill are known in the art. One example is disclosed in U.S. Pat. No. 6,095,724 (Hurt '724). For height adjustment, the stand taught by Hurt '724 uses a lever pivotally connected at a pivot point to a support collar, which is connected to the lower end of an outer column. An inner column is slidably located within the outer column. A linkage pivotally connects the lever to a locking compression collar and locking clamp. To adjust the height of the drill stand, the worker must unlock the locking clamp and then manually slide, in unison, the locking compression collar and locking clamp, the linkage, the support collar and outer column, and the lever upward or downward on the inner column, all while holding the inner column steady by positioning one of his or her feet on a foot plate. When the desired position is reached, the worker must manually lock the locking clamp.
The height adjustment and locking mechanism taught by Hurt '724 is not desirable because it is cumbersome to use. The worker must use both of his or her hands to move all the necessary components and at least one of his or her feet to steady the drill stand. When the selected height is reached, the worker must remove one of his or her hands from the adjustment and locking mechanism components to lock the locking clamp, while supporting all components with the remaining hand. In addition, drill stand taught by Hurt '724 must be picked up and carried from one drilling location to the next. Further, the drill stand of Hurt '724 does not use, teach or suggest the use of a structure that can be used to quickly and easily remove the power hand tool from atop the stand such that a second power hand tool can replace the first. This inventor has overcome these shortcomings as is described in greater detail in his co-pending application, U.S. Pub. No. US 2011/0255929 titled Universal Drill Stand, which application is incorporated herein by reference.
In view of the foregoing, however, this inventor has found that it is also desirable to have an assembly that is easily mounted to the top of a height-adjustable power hand tool stand. It is also desirable to have such an assembly where a first power hand tool can quickly and easily be removed and replaced with a second such tool. It is also desirable to have such an assembly where a plurality of hand tools can be used simultaneously. Further, it is desirable to have such an assembly that secures the power hand tool, or the plurality of hand tools, in a way that provides safety redundancy and ensures that the power hand tool or tools cannot be removed unless such is desired or required.

Saddle coupling and saddle base assembly for use with power hand tools


A developing device includes a developing agent carrying member and a latent image carrying member agent. A casing having a developing agent storing space for storing developing agent has an opening whereby a portion of the surface of the developing agent carrying member faces the latent image carrying member. A restricting member is provided within the casing to restrict the amount of developing agent supplied to the developing region. A magnetic field is provided so that the developing agent forms a magnetic brush closing off the space between the surface of the developing agent carrying member and the inner wall of the casing. A gas exhaust path is provided in an upstream space of the developing region between the surface of the developing agent carrying member and the inner wall of the casing to exhaust gas generated in the upstream space.

1. Field of the Invention
The present invention relates to a developing device applied to image formation apparatuses such as photocopiers, printers, and facsimile devices and the like, and to an image formation apparatus and a process cartridge comprising the same, and further relates to a configuration for adjusting the environmental atmosphere which affects charging properties of developing agent, and preventing soiling due to scattering of developing agent.
2. Discussion of Background Art
Generally, in order to prevent scattering of toner within an image formation apparatus, the interior of the developing device and the outside are isolated one from another by a casing, except for an opening whereby a portion of the surface of a developing agent carrying member is made to face a latent image carrying member. With this structure, a gap exists between the surface of the latent image carrying member and the casing, at the opening. Accordingly, there is the possibility that toner within the developing agent might scatter outside of the developing device through this gap. In the event that toner scatters outside of the developing device, recording media such as paper or the like upon which images are to be ultimately formed may be soiled due to the toner which has spread throughout the image formation apparatus, or normal actions of members and devices disposed within the image formation apparatus may be inhibited. Accordingly, suppressing scattering of toner outside of the developing device is an extremely important issue.
Such scattering of toner primarily occurs at a gap existing upstream in the direction of rotation of the developing agent carrying member (hereafter, referred to simply as "upstream side") of the developing region where the developing agent carrying member and latent image carrying member face one another, and a gap existing downstream in the direction of rotation of the developing agent carrying member (hereafter, referred to simply as "downstream side") thereof.
A developing device disclosed below is known, for example, as an arrangement for suppressing scattering of toner occurring at, of the above, the gap existing at the downstream side. With this developing device, a carrier collecting roller is provided downstream from the developing region, and the width of a first gap which is the gap between the developing agent carrying member and the carrier collecting roller is set so as to be larger than the width of a second gap which is a gap between the developing agent carrying member and the latent image carrying member. In the space encompassed by the latent image carrying member and developing agent carrying member and carrier collecting roller, air enters and exists from the three places of the first gap, the second gap, and a third gap which is a gap between the carrier collecting roller and the latent image carrying member. With this developing device, a magnetic brush is formed by the developing agent bristling on the surface of the developing agent carrying member, and passing through the first gap and the second gap accompanying the rotation of the developing agent carrying member in this state. At this time, each of the magnetic brushes act as slender and small propellers, such that air between the developing agent particles making up the magnetic brushes moves due to the magnetic brushes moving. Accordingly, a strong airflow is generated at the first gap and the second gap in the direction of rotation of the developing agent carrying member. On the other hand, at the third gap, there is little air following the rotation of either the carrier collecting roller and the latent image carrying member, so any airflow generated by the rotations thereof is weak. Accordingly, the airflow at this third gap is determined almost dependently on the airflow generated at the first gap and the second gap. Specifically, difference between the amount of the airflow which flows into the space through the second gap and the amount of the airflow which flows out through the first gap is the airflow generated at the third gap. With this developing device, the width of the first gap between the developing agent carrying member and the carrier collecting roller is set so as to be wider than the width of the second gap between the developing agent carrying member and the latent image carrying member. Accordingly, the airflow flowing out from the space through the first gap is greater than the airflow which flows into this space through the second gap, so the air pressure in this space drops, and acts to suction air in through the third gap. This means that an airflow is generated at this third gap which heads toward the space. This airflow is intended to suppress scattering of toner which occurs downstream of the developing region as discussed in Japanese Unexamined Patent Application Publication No. 10-3220.
On the other hand, for example, a developing device disclosed below is known as an arrangement for suppressing scattering of toner occurring at the gap existing at the upstream side. With this developing device, a partitioning member is provided between the developing agent carrying member and casing at the upstream side, for partitioning between these. With this developing device, rotation of the developing agent carrying member transports developing agent to the developing region, restricted to a predetermined thickness by a developing agent restricting member. The partitioning member is placed somewhere between the developing agent restricting member and the developing region. The space adjacent to the downstream side of the developing agent restricting member in the direction of rotation of the developing agent carrying member (doctor-adjacent space), and the gap existing on the upstream side, communicate through the two channel spaces of the space encompassed by the partitioning member and the casing (first channel space), and the space encompassed by the partitioning member and the developing agent carrying member (second channel space). According to the Document disclosing this arrangement, an airflow is generated at the second channel space following the surface of the developing agent carrying member in accordance with rotations of the developing agent carrying member. Developing agent is present at a high density at the gap between the developing agent restricting member and the developing agent carrying member (doctor gap), and accordingly, airflow through this doctor gap is poor. Consequently, negative pressure is generated at the doctor-adjacent space. Accordingly, air flows into the doctor-adjacent space through the first channel space, so an airflow heading toward the doctor-adjacent space from the gap at the upstream side is generated in the first channel space. Thus, toner floating at the upstream side of the developing region is transported to the doctor-adjacent space by this airflow, which intends to suppress scattering of toner from the gap at the upstream side to the outside of the developing device as discussed in Japanese Unexamined Patent Application Publication No. 63-159887.
Further, in order to prevent scattering of toner within the image formation apparatus, general developing devices have a structure wherein the inside of the developing device and the outside thereof are isolated one from another through the casing except for the opening portion where a portion of the surface of the developing agent carrying member faces the latent image carrying member. With such a construction as well, a gap exists between the surface of the latent image carrying member and the casing. Accordingly, there is the possibility that toner within the developing agent might scatter outside of the developing device through this gap. In the event that toner scatters outside of the developing device, toner spreading within the image formation apparatus may soil recording media such as paper or the like upon which images are to be ultimately formed, or normal actions of members and devices disposed within the image formation apparatus may be inhibited, for example. Accordingly, suppressing scattering of toner outside of the developing device is an extremely important issue.
Such scattering of toner primarily occurs at a gap existing upstream in the direction of rotation of the developing agent carrying member (hereafter, referred to simply as "upstream side") of the developing region where the developing agent carrying member and latent image carrying member face one another, and a gap existing downstream in the direction of rotation of the developing agent carrying member (hereafter, referred to simply as "downstream side") thereof. Of these, the gap at the upstream side can be closed off by employing a configuration wherein, for example, a sheet member attached to the end portion of the casing forming the gap comes into contact with the surface of the latent image carrying member. Accordingly, scattering of toner occurring at the gap on the upstream side can be readily suppressed. Conversely, the gap at the downstream side cannot be closed off with a sheet member using such a configuration. The reason is that generally, the latent image carrying member and the developing agent carrying member rotate such that the surfaces of each are moving in the same direction at the position of closest proximity, and a toner image adheres to the surface portion of the latent image carrying member downstream from the developing region, so scattering of toner occurring at the gap on the downstream side has conventionally been a difficult problem.
As a method for solving this problem, a developing device has been proposed wherein an electroconductive roller is provided within the developing device downstream of the developing region, with the electroconductive roller rotating in a direction such that the surfaces of the electroconductive roller and the developing agent carrying member are moving in the same direction at the position of closest proximity. According to the description in the Document disclosing this arrangement, an airflow is generated by the electroconductive roller and the developing agent carrying member rotating so as to be moving in the same direction at the position of closest proximity. Accordingly, a flow of air which passes from the space surrounded by the developing agent carrying member and latent image carrying member and electroconductive roller, through the space between the developing agent carrying member and the electroconductive roller, into the developing device, is formed. The toner scattered and floating in the space at the developing region is guided into the developing device by this flow of air, which is intended to suppress scattering of toner from occurring at the downstream side of the developing region as discussed in Japanese Unexamined Patent Application Publication No. 5-66663.
A developing device has been proposed wherein a carrier collecting roller is provided downstream of the developing region, and wherein the width of the first gap which is the gap between the developing agent carrying member and the carrier collecting roller is formed wider than the width of a second gap which is the gap between the developing agent carrying member and the latent image carrying member. This developing device has airflow generating means, for generating an airflow at a third gap which is the gap between the carrier collecting roller and the latent image carrying member, from outside of the developing device to the inside thereof. In the space surrounded by the latent image carrying member and the developing agent carrying member and the carrier collecting roller, the air enters and exits from the places of the first gap, the second gap, and the third gap. With this developing device, the developing agent bristles on the surface of the developing agent carrying member at the first gap and the second gap so as to form a magnetic brush, and passes through accompanying the rotation of the developing agent carrying member in this state. At this time, each of the magnetic brushes act as slender and small propellers, such that air between the developing agent particles making up the magnetic brushes moves due to the magnetic brushes moving. Accordingly, a strong airflow is generated at the first gap and the second gap in the direction of rotation of the developing agent carrying member. On the other hand, at the third gap, there is little air following the rotation of either the carrier collecting roller and the latent image carrying member, so any airflow generated by the rotations thereof is weak. Accordingly, the airflow at this third gap is determined almost dependently on the airflow generated at the first gap and the second gap. Specifically, difference between the amount of the airflow which flows into the space through the second gap and the amount of the airflow which flows out through the first gap is the airflow generated at the third gap. With this developing device, the width of the first gap between the developing agent carrying member and the carrier collecting roller is set so as to be wider than the width of the second gap between the developing agent carrying member and the latent image carrying member. Accordingly, the airflow flowing out from the space through the first gap is greater than the airflow which flows into this space through the second gap, so the air pressure in this space drops, and acts to suction air in through the third gap. This means that an airflow is generated at this third gap which heads toward the space. This airflow is intended to suppress scattering of toner which occurs downstream of the developing region as discussed in
Japanese Unexamined Patent Application Publication No. 10-3220.
Also, a developing device has been proposed having a configuration wherein the viscous airflow downstream of the developing region acts effectively to generate an airflow heading into the developing device, comprising a filter member for venting the viscous airflow which has flowed into the developing device. According to the Document disclosing this arrangement, the viscous airflow flowing into the developing device is externally vented through the filter member, so the inner pressure within the developing device rises and becomes saturated due to the viscous airflow, thereby conversely enabling an airflow blowing out at the downstream side of the developing region to be prevented. According to this device, no airflow blowing out at the downstream side of the developing region is generated, so an airflow heading into the developing device is perpetually generated, and a stable viscous airflow (suctioning airflow) can be generated at the downstream side of the developing region, thereby enabling stable suppressing of scattering of the toner generated at the downstream side of the developing region as discussed in Japanese Unexamined Patent Application Publication No. 2002-244432.
Though this is not clear regarding the developing device described in Patent Document 3, the developing devices described in Patent Document 4 and Patent Document 5 have structures wherein external air can flow into inner space of the casing through a gap (inlet gap) formed between the downstream edge portion of an opening for exposing the developing agent carrying member and the surface of the latent image carrying member. The airflow flowing in through the inlet gap suppresses scattering of the toner outside of the developing device.
Also, with image formation apparatuses such as photocopiers or printers or facsimile apparatuses or printing apparatuses, there are configurations wherein the latent image carrying member, and of the devices used for the image formation processing, a charging device, developing device, and/or cleaning devices are stored together to form a process cartridge, which is used to transfer a visible image formed on the photosensitive member which is the latent image carrying member onto a recording sheet such as paper or the like, by means of a transfer device disposed nearby the process cartridge, thereby obtaining a copied article.
It is known that in the event of performing visual image processing for an electrostatic latent image formed on the photosensitive member which is the latent image carrying member, the charging properties of the developing agent supplied affect the image concentration and gradient reproducibility, and further it is known that charging properties are readily affected by the environmental ambient atmosphere, humidity in particular. Further, in the event that discharge products such as NOx and the like formed by discharge, which is one of the methods carried out in the charging step, accumulates on the surface of the latent image carrying member, the charging properties and photosensitivity properties deteriorate, which tends to lead to deterioration in latent image carrying and so forth.
In order to solve such inconveniences, a configuration has been proposed wherein air subjected to humidity adjustment is supplied into the developing device as discussed in Japanese Unexamined Patent Application Publication No. 6-19293.
Also, the developing agent carried by the developing sleeve within the developing device is brought into contact with the photosensitive member in the state that the portion of the developing device facing the photosensitive member which is the latent image carrying member is opened to the atmosphere, but the air near the surface of the photosensitive member and the developing sleeve following the rotation thereof due to viscosity, and create a following airflow. Accordingly, the developing agent moving within the developing device may scatter toner due to reduction of pressure at the portion opened to the atmosphere, owing to the following airflow being released.
Conventionally, configurations for preventing scattering of toner have included a configuration wherein the interior of the developing device is shielded by bringing an elastic seal or the like into contact with the position on the developing sleeve which has passed the position of supplying developing agent to the photosensitive member, and a configuration comprising an electroconductive roller which can perform electrostatic adsorption of toner scattered on the perimeter of the developing sleeve which has passed the developing position and toner which would scatter from the opening as discussed in Japanese Unexamined Patent Application Publication No. 5-66663.
On the other hand, as a configuration for preventing scattering of toner due to toner being blown out owing to increased pressure within the developing device from the following airflow generated accompanying the movement of the photosensitive member and the developing sleeve, there is a configuration wherein an exhaust unit is provided partway along the channel where the developing agent which has separated from the developing sleeve flows as discussed in
Japanese Unexamined Patent Application Publication No. 2002-244432.
Also, with image formation apparatuses such as photocopiers or printers or facsimile apparatuses or printing apparatuses, visible image processing is performed by developing an electrostatic latent image formed on a photosensitive member used as a latent image carrying member with toner in a developing agent.
One-component or two-component developing agents are used with developing devices, and with either developing agent, a developing sleeve which is the carrying member for the developing agent, a developing agent stirring/mixing member, and further a layer thickness restricting member for restricting the thickness of the developing agent, are provided, and these components are disposed within a housing forming the shell of the developing device.
The developing sleeve is arranged so that a portion of the surface thereof is exposed from an opening provided to the housing, thereby bringing the developing agent on the surface thereof into contact with the photosensitive member.
Now, it is known that in the event of performing visible image processing wherein an electrostatic latent image formed on a photosensitive member is developed, the charging properties of the developing agent supplied affect the image concentration and gradient reproducibility. One of the factors causing change in the charging properties of the developing agent is the environmental ambient atmosphere, humidity in particular.
On the other hand, as for inconveniences occurring at the time of forming images, there are adverse effects of discharge products generated at the time of charging the photosensitive member. That is to say, in the event that discharge products such as NOx and the like adhere to the surface of the photosensitive member, the charging properties and photosensitivity properties are affected, leading to deterioration of the photosensitive member.
In order to solve such inconveniences, a configuration has been proposed wherein air subjected to humidity adjustment is supplied into the developing device as discussed in Japanese Unexamined Patent Application Publication No. 6-19293.
Further, the configuration of the developing device is such that a developing sleeve, a developing agent stirring/mixing member, and a layer thickness restricting member for restricting the thickness of the developing agent, are stored within a housing, with only a part of the developing sleeve exposed outwards, but the a developing sleeve and the developing agent stirring/mixing member are rotational members, and accordingly members which drag air at the surface layer portion thereof due to the rotations thereof and generate airflow. This changes the pressure within the housing, and due to a tendency to particularly become high pressure, residual toner carried on the developing sleeve following passing through the developing region configured at the portion facing the photosensitive member may scatter out from the opening of the housing, due to the increased pressure within the housing. Scattering of toner from the housing side results in inviting soiling of peripheral units, primarily the photosensitive member. Also, as a configuration for preventing scattering of toner on the developing sleeve following passing through the developing region, there is a configuration wherein the gap between the wall of the housing at the position where the developing sleeve is stored which faces the developing sleeve, and the developing sleeve, is formed greater than the gap between the wall of the housing and the photosensitive member at the position where the photosensitive member faces the wall of the housing as discussed in Japanese Unexamined Patent Application Publication No. 11-7191.
In this configuration, the toner on the developing sleeve which has passed through the developing region is readily taken into the housing using the tendency for the pressure therein to become negative, due to the increase in area occurring at the time of reaching the gap between the developing sleeve and the housing wall, which is set so as to be wider than the gap between the developing sleeve and the photosensitive member.
Further, separately from this configuration, there is a configuration wherein a carrier collecting roller is provided at a position behind the developing sleeve in the direction of movement of the photosensitive member, with the carrier collecting roller being set so as to rotate in a direction such that the portion thereof facing the developing sleeve moves in the same direction at that position, and with the gap between the carrier collecting roller and the photosensitive member at the portion facing one another being used as a gap through which air can flow as discussed in Japanese Unexamined Patent Application Publication No. 10-3220.
With this configuration, the airflow generated by rotations of the carrier collecting roller is set as the direction in which air flows through the gap where the carrier collecting roller faces the photosensitive member, by creating the tendency for the pressure to become negative at the facing gap, thereby sucking the toner which has passed through the developing region into the housing.
With the developing device disclosed in Patent Document 1, developing agent carried out the surface of the developing agent carrying member is restricted to a predetermined thickness by a developing agent restricting member due to the developing agent carrying member rotating, and thus is transported to the developing region. A fixed magnet is disposed within the developing agent carrying member at the portion from the developing agent restricting member to the developing region. Accordingly, in the space surrounded by the inner casing wall and surface of the developing agent carrying member from the developing agent restriction member to the developing region (developing agent transporting space), the developing agent bristles.
As described above, upon the developing agent on the rotating developing agent carrying member bristling, each of the magnetic brushes thereof act as propellers, such that a strong airflow is generated following the surface of the developing agent carrying member, in the direction of rotation of the developing agent carrying member. That is, a strong airflow facing the gap at the upstream side from the developing agent restricting member side is generated in the developing agent transporting space. This strong airflow causes a great amount of gas to enter into the space encompassed by the surface of the developing agent carrying member and the casing inner wall from the developing agent bristling position to the developing region (upstream space), so the pressure increases at the upstream space. Accordingly, in the event that the only way of escape from this upstream space that the gas has is the gap at the upstream side, a strong airflow is generated from the gap at the upstream side toward the outside of the developing device, and toner scattering occurs due to this airflow.
With the developing device disclosed in Patent Document 1, a gap large enough for air to flow through (gas flow space) is formed in the developing agent transporting space, between the tip of the magnetic brush formed of the bristling developing agent and the inner wall of the casing as discussed in Japanese Unexamined Patent Application Publication No. 10-3220. Also, the space adjacent to the downstream side of the developing agent restricting member in the direction of rotation of the developing agent carrying member (doctor-adjacent space) becomes negative pressure in the same way as the developing device disclosed in Patent Document 2, so the gas from the upstream space might seem to be capable of escaping to this doctor-adjacent space besides the gap at the upstream side. However, with the developing agent transporting space, the airflow heading toward the doctor-adjacent space through the gas flow channel, and the airflow heading toward the gap upstream from the magnetic brush, are flowing in mutually opposite directions. Moreover, the airflow heading toward the doctor-adjacent space is greatly inhibited by the viscous resistance of the airflow heading toward the gap at the upstream side, which has been generated by propeller-actions of the bristling developing agent. Accordingly, the gas within the upper space does not flow to the doctor-adjacent space very much, and consequently, almost all of this flows out of the developing device from the gap at the upstream side. Thus, the developing device disclosed in Patent Document 1 cannot be said to sufficiently suppress toner scattering occurring at the space at the upstream side.
On the other hand, with the developing device in Patent Document 2, negative pressure is generated at the doctor-adjacent space according to the description in this Document, stating that an airflow is generated in the first channel space, heading from the gap at the upstream side toward the doctor-adjacent space. In order to generate a strong airflow which can sufficiently suppress scattering of toner generated at the gap at the upstream side, the doctor-adjacent space needs to be under a powerful negative pressure. However, with the developing device according to this Document, the force acting to carrying the airflow out from this doctor-adjacent space is the flow generated accompanying the rotations of the developing agent carrying member in the second channel space, i.e., the surface layer airflow of the developing agent carrying member. The actions of such a surface layer airflow alone cannot yield a negative pressure necessary to sufficiently suppress scattering of the toner in the doctor-adjacent space. Accordingly, the developing device in this Document cannot generate a strong airflow at the gap at the upstream side, and cannot sufficiently suppress toner scattering.
Now, the intensity of the airflow flowing in through the inlet gap is greatly affected by the state of the airflow in the inner space of the casing. For example, in the event that part or all of the flow path of the external air flowing into the inner space of the casing from the inlet gap is closed off by the developing agent, the amount of gas flowing in through the inlet gap per time increment decreases. In such a case, the intensity of the airflow flowing through the inlet gap becomes smaller. This will be described below with reference to a specific example.
FIG. 40 is a schematic configuration diagram illustrating an example of a conventional developing device. The developing agent used in this developing device is made up of a magnetic carrier and a non-magnetic toner. The developing device 4380 has magnetic field generating means 4385 having multiple magnets disposed fixedly within a developing sleeve 4381 which is a developing agent carrying member. The developing agent, which has passed through a developing region where the developing sleeve 4381 and a photosensitive drum 4020 which is the latent image carrying member face one another passes through a channel space B between the inner wall of the casing 4384 and the developing sleeve 4381 in a state of being carried on the surface of the developing sleeve, and is returned to the inner space A of the casing. Subsequently, the developing agent is peeled off from the surface of the developing sleeve by a repelling magnetic field generated by mutually adjacent S-pole magnets 4385a and 4385b. This peeling occurs as follows. The developing agent T2 on the developing sleeve 4381 which has been transported to the region where it is affected by the repelling magnetic field is kept from integrally moving with the surface of the developing sleeve by this repelling magnetic field, and is retained as shown in the drawing. The retained developing agent T2 is pushed out by the new developing agent being consecutively sent by the rotations of the developing sleeve 4381, and finally falls off due to gravity, whereby peeling occurs. The developing agent T2 which is retained prior to peeling is in a quantitative equilibrium, due to the continuous running of the developing device 4380. In the example shown in the drawing, the channel space B is closed off by the developing agent T2 in this equilibrium state. Moreover, new developing agent is consecutively sent upon this retained developing agent T2, making for a highly dense state in which it is extremely difficult for air to pass through. In this way, the channel space B closed off by the developing agent T2 is a channel for external air to flow into the inner space A of the casing 4381 from the inlet gap C between the lower edge portion 4384a of the opening of the casing 4384 and the surface of the photosensitive drum 4020. Accordingly, the flow passing through this inlet gap C does not occur any more.
Also, in the event that a source for generating an airflow which would disturb the air flow, for example, exists in the inner space of the casing, the amount of gas flowing in through the inlet gap decreases per time increment, whereby the intensity of the airflow flowing through the inlet gap decreases. Describing with reference to the example of the developing device shown in FIG. 40, the developing device 4380 has two transporting screws 4382a and 4382b. The transporting screws 4382a and 4382b transporting the developing agent in mutually opposite directions, following the direction of the rotating axis of the developing sleeve 4381. Now, the developing sleeve 4381 rotates, and accordingly, a surface layer airflow generated by the viscosity of the air exists near the surface of the developing sleeve. Accordingly, in the event that the channel path B is not completely closed off by the developing agent T2, the external air which has flowed in from the inlet gap C can enter into the inner space A of the casing 4384 through the channel space B, due to the surface layer airflow. The external air which has entered the inner space A of the casing 4381 then is sent further into the inner space A by the surface layer airflow of the developing sleeve 4381. However, upon the developing agent being transported by the transporting screws 4382a and 4382b, a surface layer airflow is also generated on the surface of the developing agent being transported. The direction of flow of this surface layer airflow is a direction parallel to the rotational axis direction of the transporting screws 4382a and 4382b, i.e., a direction parallel to the rotational axis direction of the developing sleeve 4381, which is a direction orthogonal to the direction of flow of the surface layer airflow from the developing sleeve 4381. Accordingly, the airflow generated by the surface layer airflow of the developing sleeve 4381 attempting to send the external air deeper into the inner space A is disturbed by the surface layer flow of the developing agent being transported by the transporting screws 4382a and 4382b. In the event that this airflow is disturbed, the external air cannot readily be sent to the deeper part of the inner space A, meaning that the airflow within the channel space B becomes stagnant, and the magnitude of the airflow flowing in through the inlet gap C becomes small.
In this way, in the event that the airflow flowing in through the inlet gap C does not occur or the intensity of the airflow becomes small, the toner scattering suppression effects of the airflow disappear or deteriorate, causing a problem in that toner scattering cannot be sufficiently suppressed.
Examples of methods which can be conceived to solve this problem include a configuration wherein the developing agent T2 does not close off part or all of the channel space B, or removing the source of the airflow which disturbs the airflow. However, such methods require substantial changes in design of the developing device itself, or restrict the functions of the developing device.
Further, in a configuration wherein the environmental atmosphere around the photosensitive member is adjusted, particularly regarding humidity, and then introduced, exchanging air in a space where toner having a relatively low charged state is floating, in a short time without using forced exhausting means or the like, is difficult. Accordingly, using forced airflow generating means such as a pump or the like may be conceived, but this configuration increases the pressure within the developing device, and consequently invites scattering of toner.
On the other hand, in the event of providing an exhausting mechanism for preventing scattering of toner, this is relatively effective in cases wherein the airflow is simple in motion, such as in cases wherein the stirring means using a paddle or the like which become the source of the airflow within the developing device is singular, but in the event of using stirring means configured of multiple screw augers in order to deal with reduction in size which is in demand in recent years, the airflow generated by the stirring means is not simple since the direction of moving of the developing agent is orthogonal to the direction of motion of the developing sleeve, and for example, generating an airflow at the stirring means in the direction of suctioning the toner which is beginning to scatter becomes difficult, and sufficient suctioning cannot be performed since the pressure for suctioning is weak, and consequently, scattering of the toner cannot be completely suppressed.
Causes inviting increased pressure within the developing device other than the airflow generated by the stirring means, include the air viscously adhering to the developing agent. Viscously adhering air exists around the developing agent, and there is a portion where the amount of air increases along with the movement of the developing agent within the developing device which is a closed-off space except for one portion, and this leads to increased internal pressure.
FIG. 41 is a schematic diagram illustrating the configuration of a process cartridge comprising a developing device, and the internal pressure increasing phenomena described above will be described with reference to this drawing. With the developing device 4000B disposed within the process cartridge 4000A shown in FIG. 41, in the event that a developing sleeve 4000B1 rotates in the direction indicated by the arrow in the drawing, the residual toner 4000T0 on the perimeter of the developing sleeve 4000B1 which has passed the developing region where the magnetic brush is made to face the photosensitive member 4000C and to come into contact therewith, moves along with the rotations of the developing sleeve 4000B1. The residual toner 4000T0 falls off of the developing sleeve 4000B1 due to the repelling magnetic filed due to magnets 4000D1 and 4000D2 of the same polarity which are disposed within the developing sleeve 4000B1.
On the other hand, a screw member 4000E for drawing up the stirred developing agent to the developing sleeve 4000B1 is provided near the developing sleeve 4000B1, and the surface layer air which moves along with the rotations of the screw member 4000E is concentrated a the position where the toner is repelled and falls off of the developing sleeve 4000B1. Accordingly, at the position where the developing sleeve 4000B1 and the screw member 4000E face one another, the pressure increases due to the density of the air increasing owing to the surface layer air of both being collected at this position, whereby the pressure increases at the range past the developing region in the direction of rotation of the developing sleeve 4000B1. Accordingly, the toner suctioning operations, due to the negative force generated in the downstream direction of motion of the magnetic brush remaining on the developing sleeve 4000B1, are not performed suitably. Consequently, toner scattering preventive actions due to the above-described negative pressure cannot be effectively obtained.
Further, in the event of suctioning the toner past the developing region into the housing of the developing device due to the tendency for the pressure to become negative, suctioning due to negative pressure can be made in the event that all of the toner in the developing agent carried in a bristled state on the surface of the developing sleeve behaves in the same way, but in reality, the behavior in movement differs between the tip of the brush and the surface side of the developing sleeve.
FIG. 42 is a model diagram illustrating the way in which the developing agent moves, passing through the developing region, under negative pressure from the housing side. In FIG. 42, the developing agent which has passed through the developing region moves by being carried by the developing sleeve 4000B1, but there are cases wherein the developing agent at the tip of the brush is scraped off due to the shock of coming into contact with the wall face of the housing facing the developing sleeve 4000B1. The developing agent bristling on the surface of the developing sleeve generates moment in accordance with the rotations of the developing sleeve. Accordingly, the developing agent situated at the tip of the brush is subjected to greater shock at the time of coming into contact with the wall face of the housing as compared to the base side of the brush, so part of the developing agent more readily falls off at the time of being subjected to shock. The toner contained in the developing agent readily falls of and floats upon being subjected to shock in the event that the charge has weakened following passing through the developing region. Such toner may scatter outside from the housing due to the effects of the airflow which will be described alter.
The airflow at the surface of the developing sleeve at the time of the developing sleeve 4000B1 rotating is uniform at the surface of the developing sleeve, but the flow of the air following around at the tip side of the developing agent which is bristling is in a relation opposite to that so far, due to the reactive force (collision force) received upon coming into contact with the wall face of the housing. Particularly, the airflow at the time of coming into contact with the wall face of the housing is the opposite to the airflow at the developing sleeve surface side, also due to effects of the viscosity with the wall face, and the speed thereof may be instantaneously negated.
At the tip of the brush where such a phenomenon is occurring, in the event that there is a tendency for negative pressure to occur a the position that the developing agent, which has passed through the developing region by pumping due to movement of the developing agent, enters the housing, the developing agent flows backwards toward the position that the developing agent enters the housing due to the negative pressing, as shown in FIG. 43 (indicated as airflow blowing out in FIG. 43).
At the position where the developing agent enters the housing, the surrounding air (the airflow denoted by reference numeral 4000PS in FIG. 42) has a tendency to be taken in as shown in FIG. 42, using the pumping action of the developing agent carried on the developing sleeve, so the air taken in mixes with the air moving along with the developing agent reversing direction of flow on the surface of the developing sleeve 4000B1 and readily generates turbulence, so the toner convecting due to this disturbance scatters outside of the housing upon being affected by air moving along with the movement of the photosensitive member (the airflow denoted by reference numeral 4000PS1 in FIG. 42).
Consequently, part of the toner contained in the developing agent which has passed through the developing region may scatter again from the housing, leading to a situation wherein the reduction in pressure to prevent scattering may instead cause scattering of toner.
Accordingly, the present invention has been made in light of the background in which various technical problems exist, and it is a first object thereof to provide a developing device and an image formation apparatus whereby effects of suppressing scattering of toner which occurs at the upstream side of the developing region as described above can be improved.
Also, it is a second object of the present invention to provide a developing device, an image formation apparatus, and a process cartridge wherein scattering of toner which occurs at the downstream side of the developing region can be suppressed in a stable manner.

Toner scatter suppressing developing device, image formation apparatus and process cartridge


A variable electronically controlled phase shift circuit including a phase splitter stage including a 90 degree phase divider to split an RF input signal into 0 and 90 degree components. Each split signal is further split into two pairs that are displaced in phase by 180 degrees to provide, 0 degree, 180 degree and degree, 270 degree pairs. Four signals of the signal pairs are applied to a phase controller subcircuit wherein one of each of the two signal pairs may be attenuated by a control signal. The signal pairs from the phase controller sub-circuit are then summed and the summed pairs are combined into a single output signal. The phase of the output signal is controlled by varying the relative amplitudes of at least one of the component signals of the 0 degree, 180 degree and 90 degree, 270 degree pairs by means of the control signals on the phase control sub-circuit.

Phase modulation techniques are used for communication systems, and such phase modulation techniques incorporate phase shift circuits of the type wherein the phase shift is adjustable over a 360 degree range.
An example of a typical adjustable phase shifter for adjustably providing a 360 degree range of phase shift to RF signals is disclosed in U.S. Pat. No. 4,395,687 issued Jul. 26, 1983 to Belohoubek and entitled, "Adjustable Phase Shifter". In the U.S. Pat. No. 4,395,687 the RF signals are divided into three equal parts, adjusting the relative amplitudes of the parts of the RF signals and combining the three parts of the RF signals at relative phase angles of 0, 120 and 240 degrees.
In U.S. Pat. No. 4,355,289 issued Oct. 19, 1982 to Beyer et. al. and entitled "Phase Shift And Amplitude Modulator", a parallel modulator for digital phase modulation is described wherein the outputs of two amplitude controllable bi-phase modulators are combined in quadrature to form the basis for the output signal; by control of the amplitude and phase--either 0 or 180 degrees--of each of the bi-phase modulators and an output signal having an arbitrary phase angle is produced.
The parallel modulator is capable of independent phase and amplitude control and employs bi-phase modulators.
Each bi-phase modulator utilizes diodes which are always turned on so as to minimize the parasitic reactances associated with the diodes, and each bi-phase modulator includes a power splitter which splits the continuous wave carrier input signal into two intermediate signals which are equal in amplitude and 180 degrees out of phase. At microwave frequency operation, each of the two intermediate signals are coupled through directional couplers to a pair of PIN diodes which are connected together at a common summing junction.
With proper adjustment of the DC bias level, both diodes will be operated fully on, and the two microwave frequency intermediate signals conducted through the diodes will exactly cancel at the summing junction--a null condition. If the bias current provided to the diode which is conducting the intermediate signal at 0 degree phase angle is reduced from the null condition current, the intermediate signal at 180 degrees will not be completely canceled at the junction, and thus the phase of the output signal will be at 180 degrees.
The output amplitude may thereafter be continuously controlled by varying the bias current of the diode conducting the 0.degree. intermediate signal.
Two bi-phase modulators of the Beyer patent may be combined in a parallel modulator configuration to yield a modulated output signal which, with proper control of the bias inputs to the bi-phase modulators, can be controlled to an arbitrary phase angle between 0.degree. and 360 degrees, and to a continuously controllable amplitude.
In U.S. Pat. No. 4,549,152 issued Oct. 22, 1985 to Kumar and entitled, "Broadband Adjustable Phase Modulation Circuit, a phase modulation circuit is described which provides at an output terminal an output signal controllably shifted from 0 to 360 degrees relative to an input signal provided at an input terminal and includes a first 90 degree coupler connected between the input terminal and second and third 90 degree couplers, four gain controllable amplifiers, fourth and fifth 90 degree couplers and an in phase combiner with its output connected to the output terminal. Two of the amplifiers are connected between the second and fourth couplers. The additional amplifiers are connected between the third and fifth couplers. The fourth and fifth couplers are connected to the inputs of the in-phase combiner. The gain through the various amplifiers is adjusted to control the amount of phase shift through the circuit.
U.S. Pat. No. 4,581,595 issued Apr. 8, 1986 to Silagi entitled "Phase Shift Network With Minimum Amplitude Ripple", describes an improved phase shift network which includes a splitter for receiving an input signal and providing outputs which are coupled through all pass networks to produce signals differing in phase by predetermined angle. The signals from the all pass networks are coupled through variable attenuators having their outputs recombined in a combiner to produce an output representing the input signal phase shifted by a predetermined angle. The phase shift may be adjusted by changing only one variable attenuator at a time to produce phase shifts of 90 degrees or greater.
U.S. Pat. No. 4,870,374 issued Sep. 26, 1989 to Harris entitled "Modulator Producing Phase Modulation By Combining Amplitude Modulated Signals", describes still another system for using the modulation of the phase of a RF carrier as means of transmitting information. The RF input is split into four quadrature components each of which is passed through individual amplitude control attenuators and then summed in a combiner to create the required phase-controlled RF signal. The resultant signal is then amplified in an RF signal amplifier chain as required to achieve the desired output level. The RF output level is sampled and routed back to an in-phase splitter the output of which is compared to the corresponding individual quadrature components of the unmodulated RF signal to generate a signal which is compared with a processor generated modulation reference signal in a control loop amplifier and the resulting error signal is applied to the individual attenuators to adjust the output amplitude of each quadrature component. The quadrature components are then combined to obtain the desired phase-modulated RF output signal.

Continuously variable electronically controlled phase shift circuit


Ac-Sar-Gly-Val-D-allo-Ile-Thr-Nva-Ile-Arg-ProNHCH2CH3 Crystalline Form 1, ways to make it, compositions containing it and methods of treatment of diseases and inhibition of adverse physiological events using it are disclosed.

The acetic acid salt of Ac-Sar-Gly-Val-D-allo-Ile-Thr-Nva-Ile-Arg-ProNHCH2CH3.CH3CO2H (AcXGVI*TNIRPNHCH2CH3.CH3CO2H) is useful for treating diseases that are caused or exacerbated by angiogenesis.
Because the crystallinity of this compound may effect, among other physical and mechanical properties, its solubility, dissolution rate, hardness, compressability and melting point, there is an existing need in the process and therapeutic arts for identification of crystalline forms of AcXGVI*TNIRPNHEt.CH3CO2H and ways of reproducibly making it.


A sweeping machine for picking up debris from a surface includes a frame and wheels attached to said frame to support the frame of the sweeping machine over the surface being swept. A cylindrical brush is rotatably attached to said frame. The cylindrical brush includes a pattern of rows of sweeping material having N sections that have a first spiral in a first direction and N+1 sections of the brush that have a second spiral in a second direction. Two of the N+1 sections having the second spiral are located on the ends of the brush. The spiral is selected so that it augers or moves debris from a desired or selected side of the sweeping machine toward the center of the brush. The sweeping machine also includes a mechanism for rotating said cylindrical brush.

There are many types of sweeping machines for removing various types of debris from a surface, such as the ground, a floor or a parking lot. Many of these sweeping machines use a rotating cylindrical brush to contact the surface being swept. The rotating cylindrical brush is used to lift various types of debris from the floor or surface and throw it into a debris hopper located near the rotating cylindrical brush. The machine moves the rotating cylindrical brush over the surface being swept. The rotational velocity of the cylindrical brush produces a velocity at the ends of the brush that differs from the velocity of the machine as it moves over the surface being swept. The brush can be rotated in either direction. There are many types of sweepers. Two types of sweepers are forward throw sweeper and indirect throw sweepers. Forward throw sweepers use a brush rotated backward with respect to the travel of the sweeping. The debris is thrown forward and collected in a container which is forward of the brush. Indirect throw or over-the-top sweepers use a brush rotated in either direction with a debris container located for collection of the debris.
Sweeping machines are used in a variety of environments. For example, some sweeping machines remove debris from roads and streets. Others are used to remove debris from parking lots and others are used to remove debris from factory floors. In short, there are many applications for sweeping machines. Sweeping machines also remove different types of debris. Certain brush designs can be employed to enhance a sweeping machine's ability to pick up or remove certain types of debris.
There are several types of brush fill patterns which are customarily used. One predominant type of brush fill pattern is termed full fill or high density. In a full fill type brush the bristles or other sweeping material are closely packed together or in a highly dense configuration. The bristles or other sweeping material of a full fill brush can be placed in almost any type of pattern to form a full fill type brush. The full fill brush presents a substantially solid mass of bristles or other sweeping material. Full fill type brushes are generally effective in removing relatively thin layers of fine material from surfaces being swept. Fine materials, also referred to as fines, include very fine particles, such as sands which are used in foundries for making molds, cement dust, and sand found in parking lots or in streets.
A second predominant type of brush fill pattern has spaces between rows of bristles or other sweeping material. This second type of brush has a number of variations. For example, a brush called a double row brush has two rows of closely spaced bristles or other sweeping material. This is called a double row. There is a larger space between each double row of bristles or other sweeping material. This second type of brush fill pattern is better for removing bulkier debris or deeper layers of fine material.
The second predominant type of brush fill pattern is formed by placing the bristles or other sweeping material in one of several patterns. One pattern is to place the bristles or other sweeping material in straight lines along the brush tube. The straight lines are substantially parallel to the axis of the brush tube. Brushes with straight line pattern of bristles or other sweeping material and spaces between the straight bristles or other sweeping material cause a brush to bounce or jump excessively because as the brush rotates, the brush alternates between having all the bristles or other sweeping material in one row of the brush in contact with the surface being swept and no bristles in contact with the surface being swept. The result of brush bounce is chatter lines of fine debris being left on the surface that has been swept. Brush bounce may also cause vibration of the sweeping machine.
To prevent the brush from bouncing, the rows of bristles are placed in spiral patterns along the surface of the brush tube. The spiral pattern has a number of spiral tufts placed in a pattern with spaces between the spiral pattern of tufts of sweeping material. When the tufts and spaces are in a spiral pattern, the amount of brush material in contact with the surface being swept is substantially constant as the brush rotates so as to minimize the amount of brush bounce. In other words, at any rotational position of the brush, there is always some brush fill material in contact with the surface being swept to support the brush as it rotates. Spiral pattern brushes also have a problem. Debris or fines may travel along the length of the brush. The spiral pattern having spaces between the spirals acts as an auger that may move the debris or fines in one direction along the surface of the brush. This can be a disadvantage since some debris or fines may be augured out at one end of the brush.
To prevent fines and debris from traveling along the length of the brush, many brush designs use a single or double herringbone pattern to break up the auguring effect. The herringbone pattern may also be termed a chevron pattern or may be termed as alternating spirals. These herringbone patterns prevent the migration of debris and material being swept from being augured down the length of the brush. The herringbone pattern allows material being swept to only travel to the point where the spiral changes directions. As a result, these types of brushes are more effective at sweeping up certain types of debris and preventing the auguring along the entire length of the brush during rotation.
Herringbone type brushes do auger debris a certain length. The herringbone patterns can be thought of as using one full chevron or a multiple of one full chevron. One full chevron will have a first spiral in a first direction and a second spiral in a second direction. Brushes which do use the herringbone patterns auger debris along the length of the spiral until the spiral changes directions. The problem with a pattern of brush which has a number of full chevrons or an the same number of different direction spirals is that at both ends of the cylindrical brush, the debris or material being swept will be either augured outward or inward from the end of the cylindrical brush. The direction of auguring is dependent on the orientation of the chevrons with respect to the rotational direction of the brush. It is desirable to rotate the brush so that the debris and fines auger toward the middle of the brush. However, if the chevrons on the brush are always oriented one way, the bristles or brush material forming the brush can take a set. In other words, like a push broom, the bristles or brush material can bend over and become less effective. To prolong the life of a cylindrical brush, regular maintenance requires that the brush be switched or flipped end to end to change the orientation of the chevrons and prevent the bristles or other sweeping material or brush fill material from taking a set in one direction. Flipping the brush end to end changes the direction of the force on the tufts or bristles of the brush. When flipped or switched, the chevrons of the cylindrical brush will auger debris toward both ends of the brush which increases the possibility of trailing. Trailing is where some amount of debris or fines is left at the ends of the brush after the sweeping machine has passed.
Auguring of fines or other debris is troublesome when you consider that many times much of the debris is located on one end of the brush. For example, in streets it has been found that the vast majority of the debris and fines are located on one end of the brush, mainly near the curb and in the gutter. In this instance, there is a need for a cylindrical brush for use on a sweeping machine that will auger the fines or other debris inward toward the center of the brush while it is rotating no matter what orientation of the brush fill pattern of the cylindrical brush. There is also a need for a cylindrical brush that will prevent the material being swept from traveling along the entire length of the brush. There is also a need for a brush that will auger the debris or fines being swept in toward the center of the brush from a selected or desired side of a sweeping machine even when the brush is flipped end-for-end and the brush fill material is re-orientated. For example, it is necessary to have a brush that will auger the material being swept inward despite whether it is in a first orientation or whether it has been flipped end-to-end to a second orientation for maintenance purposes. There is also a need for a sweeping brush that will consistently pick up varying types of debris on a variety of surfaces and one that limits axial migration of debris toward the ends of a rotating cylindrical brush. There is also a need for a brush that minimizes trailing. There is a further need for a sweeping machine that is smooth and stable during its operation.

Cylindrical brush for a sweeping machine


An information notification apparatus includes a first reception unit that receives a first state change notification indicating that the operating state of an electrical appliance has changed to a first state, a transmission unit that transmits a state notification indicating that the operating state of the electrical appliance is the first state to an information terminal, and a second reception unit that receives an acknowledgement notification. The first reception unit further receives a second state change notification indicating that the electrical appliance has been changed to a second state from the electrical apparatus. The transmission unit calculates a correlation value for each of information terminals and transmits the state notification to an information terminal having a calculated correlation value higher than a threshold value, the correlation value indicating a degree of likelihood that the owner of the information terminal has performed an operation corresponding to the second operating state.

If information about electrical appliances needed by users has been set in advance, conventional information notification apparatuses can notify mobile terminals held by users of information about electrical appliances based on the set information. This enables the users to remotely control electrical appliances in accordance with the notified information, using their mobile terminals (see PTL 1, for example). FIGS. 12 and 13 illustrate a conventional information notification apparatus disclosed in PTL 1.
Referring to FIG. 12, an information notification apparatus 10 for managing information is configured by control means 11 for controlling exchanges of information between each information source and each mobile information device, wireless communication means 12 for transmitting and receiving data to and from each information source and each mobile information device using a radio signal, a domestic antenna 13 for use in exchanging data between each information source and each mobile information device, wiring means 14 for connecting the information notification apparatus 10 and the domestic antennas 13, and storage means 15 for storing information transmitted from each information source and each mobile information device.
The information notification apparatus 10 disclosed in PTL 1 checks the codes of mobile information devices to be notified of, using an exemplary notification-destination specification list illustrated in FIG. 13, and transmits notification information. The method of notification can be set in the notification-destination specification list, and examples of the notification methods include simultaneous notification to all users, notification to a single user, and sequential notification to users at a fixed time interval. Then, in order to contact an operator with respect to the notification information, a content to be displayed on the mobile information devices and notification means using a physical phenomenon such as sound, light, or vibrations are selected and again converted into radio signals by the wireless communication means 12, and the radio signals are transmitted to the mobile information devices with the domestic antenna 13.
Accordingly, in the case where a single electrical appliance is shared by a plurality of users such as a case where an electrical appliance is shared by family members, it is possible to notify only a user who needed information of necessary information and to give a notification of effective information on a space-limited display screen.

Information notification apparatus, information notification system, information notification method, and program

PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.


The invention comprises an elongated device adapted for insertion, including self-insertion, through the body, especially the skull. The device has at least one effector or sensor and is configured to permit implantation of multiple functional components through a single entry site into the skull by directing the components at different angles. The device may be used to provide electrical, magnetic, and other stimulation therapy to a patient's brain. The lengths of the effectors, sensors, and other components may completely traverse skull thickness (at a diagonal angle) to barely protrude through to the brain's cortex. The components may directly contact the brain's cortex, but from there their signals can be directed to targets deeper within the brain. Effector lengths are directly proportional to their battery size and ability to store charge. Therefore, longer angled electrode effectors not limited by skull thickness permit longer-lasting batteries which expand treatment options.

1. Field of the Invention
The present invention relates to medical devices, systems and methods for accessing cranial and intracranial structures. Specifically, the invention is directed to altering brain function and treating cranial and intracranial pathology. More specifically, the invention is directed to the surgical implantation of electrodes or other devices within or through the cranium to alter or improve brain function and pathological states such as stroke, seizure, degeneration, and brain tumors. Most specifically, the invention is directed to minimizing surgical methods and risks and maximizing the length of devices that can be implanted within or through the cranium and their ability to hold charge.
2. Description of the Related Art
Electrical stimulation of the brain can improve and ameliorate many neurologic conditions. Examples of the success of brain stimulation include deep brain stimulation for Parkinson's Disease, tremor, dystonia, other movement disorders, epilepsy, and pain. Additionally, potential new sites of deep brain stimulation demonstrate promising results for other conditions such as obesity, depression, psychiatric disorders, memory, migraine headache, and minimally conscious states.
Deep brain stimulation involves placing a long electrode through a burrhole in the cranium to a target deep to the surface of the brain. The electrode is placed under stereotactic guidance which is performed with or without a frame. Frame based systems such as the Leksell frame require that a rigid stereotactic frame is clamped to the skull through a number of screws that are fixed to the cranium. Frameless systems utilize fiducial markers placed on the skin. In both methods, an MRI (magnetic resonance imaging) or CT (computed tomography) scan is performed with the frame or fiducial markers in place. In frame based stereotaxy, computer assisted reconstruction of the brain and target area is performed to localize the target in relation to the coordinates of the frame. In frameless stereotaxy, a three-dimensional reconstruction of the cranium and brain is matched to the three-dimensional configuration of the fiducial markers. The end result in both cases is the ability to place electrodes accurately into virtually any part of the brain.
The cerebral cortex is another structure that yields a large potential for therapeutic intervention. In deep brain stimulation, the electrode passes through the cerebral cortex as well as subcortical brain structures to reach the affected deep brain nuclei and therefore risks injury to the intervening healthy brain tissues as well as blood vessels. These unnecessary yet unavoidable injuries can potentially result in loss of brain functions, stroke, and intracranial hemorrhage. On the other hand, stimulation of the cerebral cortex is safer because electrodes are placed on the surface of the brain or even outside the covering of the brain, i.e. dura mater, a technique called epidural electrode stimulation. Additionally most of the subcortical or deep brain structures have connections with known targets in the cortex, making these targets candidates for cortical stimulation. Accordingly, directly stimulating the cortex can affect subcortical and deep brain structures that directly or indirectly communicate with the cortical targets. Previous studies have demonstrated success in using cortical stimulation for the treatment of epilepsy, stroke rehabilitation, pain, depression, and blindness.
In addition to the treatment of pathologic conditions, brain stimulation and recording provides the virtually unlimited potential of augmenting or improving brain function. These technologies allow the brain to bypass dysfunctional neural elements such as due to spinal cord injury, amyotrophic lateral sclerosis (ALS), stroke, multiple sclerosis (MS), and blindness. Brain recording and stimulation techniques in these cases provide a bridge for neural signals to cross injured or dysfunctional elements both on the input as well as the output side. For example in the case of ALS or a patient with locked-in syndrome, the patient is awake and conscious but without any ability to interact with the environment. These patients are essentially trapped within their brain. Recently, it has been demonstrated that by placing recording electrodes directly on the surface of the brain, these patients can learn to control computer cursors and other devices through their own brainwaves. This method of direct control of external devices through brainwaves is called brain-machine interface
Brain-machine interface has also been implemented using brainwaves recorded outside the cranium—electroencephalography (EEG), which detects the neural signals passing through the cranium with electrodes placed on the scalp. Although noninvasive, brain-machine interface using EEG signals is currently limited from the significant dampening of the brainwave's amplitude by the cranium. Only the largest potentials among the brain signals are detectable by the EEG approach.
Similarly the cortex and some subcortical fibers can be activated through the cranium by transcranial magnetic stimulation (TMS) or transcranial direct current stimulation (tDCS). In this approach, magnetic waves (TMS) or electrical currents (tDCS) are activated on the scalp outside the cranium and transmitted through the cranium to activate parts of the cortex and subcortical fibers. TMS has been effective in treating a number of disorders such as depression, migraines, and movement disorders. Additionally some reports suggest that TMS may be able to boost memory and concentration. Similarly tDCS appears to improve some forms of learning when applied in low doses. This evidence suggests that stimulation of the cortex may have a large, virtually unlimited, variety of applications for treating central nervous system pathology as well as enhancing normal brain functions.
Electrical stimulation has also been applied effectively for the treatment of certain tumors. By applying an electrical field that disrupts the physiology of tumor cells, tumors have been found to shrink. Tumors in the brain, particularly those close to the surface of the brain such as meningiomas may also be treated by electrical stimulation. In addition to electrical fields, heat (thermoablation) and cold (cryoablation) have also demonstrated effectiveness towards tumors.
Prior art and current state of the art for brain stimulation technologies require the placement of electrodes either through a craniotomy where a flap of the skull is removed and then replaced, or a burr hole where a small hole is drilled in the skull and the brain can be visualized. These procedures necessitate a minimum of an overnight stay in the hospital and pose risk to injury of the brain due to the invasiveness of the techniques. Additionally these "open" techniques pose special challenges for securing the electrode as most technologies require a lead to exit the hole in the skull. Unless these electrodes are tethered by a suture or device, there is possibility of migration or movement, particularly in the context of continuous pulsatile movement of the brain in relation to the skull.
Current techniques for cortical stimulation also risk the development of scarring of the cortex as well as hemorrhage. With long term placement of foreign objects on the brain or spine, scarring (gliosis and inflammation) occurs. This is seen with both spinal cord stimulators placed on the spinal cord as well as prostheses placed on the surface of the brain. Scarring distorts the normal brain architecture and may lead to complications such as seizures. Additionally, the placement of devices on the surface of the brain poses risks of hemorrhage. A previous clinical case illustrates the dangers: a patient who received subdural cortical electrode implantation suffered significant intracranial hemorrhage after suffering head trauma. Thus in the case of a deceleration injury like that seen in traffic accidents or falls, the imperfect anchoring of the electrode and the mass of the electode may cause the electrodes to detach and injure the brain. Blood vessels also can be sheared from the sudden relative movement of the electrode on the brain, leading to subdural, subarachnoid, and cortical hematomas. However, if the electrodes were embedded within the skull then there is no risk of this type of shearing injury during traumatic brain injury such as from sudden impact accidents.
In order to expand the indications of brain stimulation to a larger population of patients, the invasiveness of techniques for placement of the electrodes needs to be minimized. As many surgical specialties have demonstrated, minimized surgical approaches often translate into safer surgeries with shorter hospital stays and greater patient satisfaction.
Recent advances in the miniaturization of microelectronics have allowed the development of small, completely contained electrode systems, called the bion, that are small enough to be injected into muscle and other body parts through a syringe. This type of microelectrode device contains stimulation and recording electrodes, amplifier, communication, and power components all integrated into a hermetically sealed capsule. While some bion devices have batteries integrated with the unit, others are powered by radiofrequency transmission. Although muscle and other body parts allow the implantation of bion electrodes, the cranium poses a challenge to the bion because the cranium is roughly 1 cm or less in thickness. This finite thickness limits the size of the electronic components as well as the size of the battery. Battery capacity (the amount of energy stored within the battery) determines the length of time between charges in a rechargeable battery and is effected by the length of the battery. In the case of the bion, an injectable device that demands a small diameter, the battery capacity is directly related to the length of the battery. A longer bion electrode permits a longer battery and hence greater battery capacity and a longer run time without recharging.
Some patents exist covering implantable stimulators and electrical stimulation therapy systems. However, these patents are not specially adapted for insertion through the skull with multiple components through a single site by means of introducing some components at non-orthogonal angles.
In the present invention an electrode can communicate with and work together with other electrodes and supporting components (i.e. receivers, transmitters, batteries, rechargers, etc.) for an integrated therapy system with multiple components insertable through the same

Insertion of medical devices through non-orthogonal and orthogonal trajectories within the cranium and methods of using


By using an improved back reflecting layer, a photovoltaic cell having excellent migration resistance and a high photoelectric conversion efficiency is provided at high productivity. The photovoltaic cell includes a metal layer comprising a silver-aluminum alloy having a content of silver equal to or less than 30 atomic percent, the rest being aluminum, or a metal layer comprising a copper-aluminum alloy having a content of copper between 30 and 50 atomic percent, the rest being aluminum. It is preferable to form these layers at a relatively low temperature by sputtering, particularly at a temperature equal to or less than 110.degree. C. for the silver-aluminum alloy and at a temperature equal to or less than 120.degree. C. for the copper-aluminum alloy.

1. Field of the Invention
This invention relates to a photovoltaic cell. More particularly, the invention relates to a high-performance photovoltaic cell which can be reliably used for a long time and which can be subjected to mass production at a low cost.
2. Description of the Related Art p U.S. Pat. No. 4,419,533 discloses a photovoltaic cell in which the surface of a metal layer has a textured structure and in which a back reflecting layer having a transparent layer formed thereon is provided. According to such a configuration, solar light which has not been absorbed by semiconductor layers, comprising thin-film semiconductors, is returned to the semiconductor layers to effectively utilize the incident light. According to the textured structure of the surface of the metal layer and/or the transparent layer, the length of the optical path of reflected light is lengthened, thereby contributing to an increase in the short-circuit current density.
FIGS. 3(a) and 3(b) are graphs illustrating a state in which the absorption of incident light increases as a result of adoption of a back reflecting layer having a textured structure. FIG. 3(a) illustrates the spectral sensitivity of an a(amorphous)-SiGe solar cell in which a specular silver layer is used as a metal layer serving as a back reflecting layer. FIG. 3(b) illustrates the spectral sensitivity when a textured structure silver layer is used instead of the specular silver layer shown in FIG. 3(a). In the solar cell shown in FIG. 3(a), light in the wavelength regions of 700 nm, 780 nm and 850 nm is not effectively utilized in the semiconductor layers comprising an a-SiGe semiconductor. On the other hand, in the solar cell shown in FIG. 3(b), a drop in the spectral sensitivity (Q-value) is hardly observed in these wavelength regions. Accordingly, it can be understood that the use of a back reflecting layer having a high reflectivity for light of these wavelength regions is effective for increasing the conversion efficiency.
FIG. 2 illustrates the results of studies on the reflectivity for Ag, Al, Cu and Ni monolayer films having a thickness of 200 nm. It can be understood from FIG. 2 that while silver and copper show high reflectivity values at the entire wavelength region of 700-1,000 nm required for thin-film semiconductors used in the present invention, aluminum has a minimum value in the vicinity of the wavelength of 800 nm, and nickel has low reflectivity values in the entire wavelength region. Accordingly, silver and copper are suitable as a material for forming a metal layer serving as a back reflecting layer.
Although the use of silver or copper having a superior reflectivity value as a metal for the back reflecting layer is very advantageous for obtaining a solar cell having a high conversion efficiency, these metals, particularly, silver, are known as metals causing electrochemical migration.
Electrochemical migration (hereinafter abbreviated as "migration") is a phenomenon in which, when a metal in the form of a foil, a plated substance, a paste or the like, is used in high humidity while contacting a hygroscopic or hydrophilic insulator in a state in which a DC voltage is applied, the metal grows in the form of a dendrite or penetrates the surface or the inside of the insulator due to electrolysis to form a conductive path. There have been reported that for some metals, conditions other than the ones described above are required. For example, migration occurs in the presence of distilled water and an electric field for silver (Ag), copper (Cu), lead (Pb) and the like (the growth rate of dendrite crystals of Ag is particularly high). For gold (Au), palladium (Pd),indium (In) and the like, migration occurs when halogen ions are present. On the other hand, migration does not occur under the above-described conditions for aluminum (Al), nickel (Ni), iron (Fe) and the like.
In solar cells which will be used in various environments, short circuiting between electrodes due to the above-described migration is a problem during the use of a long time period. For example, consider a case in which solar cells practically used outdoors are in an environment of high temperature and high humidity. In general, since the output voltage of a single solar cell is low, a plurality of submodules (each comprising the above-described thin-film-semiconductor solar cells assembled in the form of a module) are used by being connected in series. When such solar cells are partly covered with fallen leaves or the like, the output currents of the submodules of the covered portion become much smaller than those of other submodules, thereby substantially increasing the internal impedance. As a result, the output voltages of the other submodules are applied in a reverse direction. That is, the conditions for generating migration of high temperature, high humidity and the application of an inverse bias are realized, thereby causing short circuit between electrodes and damage of the submodules. This a technical problem particularly to be solved when using Ag or Cu having a high reflectivity suitable for the back reflecting layer.
In order to solve such a problem, a metal having better migration resistance, i.e., Al, Ni or the like, may be used instead of Ag or Cu. However, when using Al, Ni or the like, although the migration problem is lessened, the photoelectric conversion efficiency decreases because the reflectivity of such a metal is lower than that of Ag or Cu. Particularly, a portion where the reflectivity drops in the vicinity of the wavelength of 800 nm is present for Al.
Japanese Patent Laid-Open Application (Kokai) No. 3-166770 (1991) describes the provision of a diffusion prevention layer comprising copper oxide in order to prevent diffusion of copper used for the back reflecting layer into the semiconductor layers. This approach, however, requires an additional process of oxidizing the surface of copper.