A system has a pipe handling apparatus with an arm between a first position and a second position, a derrick having a window through which the pipe handling system delivers a pipe to a wellhead, and a header mounted in the window of the derrick. The header receives the arm of the pipe handling system when the arm is in the second position. An outside surface of the header suitably fits within the window of the derrick. An inside surface of the derrick suitably receives the arm. The inside surface resists an upward motion and a sideways motion of the arm. The header has a body that has a head and legs.

1. Field of the Invention
The present invention relates to the delivery of tubulars from a horizontal orientation to a vertical orientation at a wellhead. More particularly, the present invention relates to pipe handling apparatus that positions tubulars at a wellhead. More particularly, the present invention relates to controlling undesirable forces that are created while positioning a tubular at a wellhead.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98.
Drill rigs have utilized several methods for transferring tubular members from a pipe rack adjacent to the drill floor to a mousehole in the drill floor or the well bore for connection to a previously transferred tubular or tubular string. The term "tubular" as used herein includes all forms of pipe, drill pipe, drill collars, casing, liner, bottom hole assemblies (BHA), and other types of tubulars known in the art.
Conventionally, drill rigs have utilized a combination of the rig cranes and the traveling system for transferring a tubular from the pipe rack to a vertical position above the center of the well. The obvious disadvantage with the prior art systems is that there is significant manual involvement in attaching the pipe elevators to the tubular and moving the pipe from the drill rack to the rotary table at the well head. This manual transfer operation in the vicinity of workers is potentially dangerous and has caused numerous injuries in drilling operations. Further, the hoisting system may allow the tubular to come into contact with the catwalk or other portions of the rig as the tubular is transferred from the pipe rack to the drill floor. This can damage the tubular and may affect the integrity of the connections between successive tubulars in the well.
One method of transferring pipe from the rack to the well platform comprises tying one end of a line on the rig around a selected pipe on the pipe rack. The pipe is thereafter lifted up onto the platform and the lower end thereof is placed into the mousehole. The mousehole is simply an upright, elongate cylindrical container adjacent to the rotary table which supports the pipe temporarily. When it is necessary to add the pipe to the drill string, slips are secured about the drill string on the rotary table thereby supporting the same in the well bore. The pipe is disconnected from the traveling equipment, and the elevators, or the kelly, are connected to the pipe in the mousehole. Next, the traveling block is raised by positioning the pipe over the drill string. Tongs are used to secure the pipe to the upper end of the drill string. The drill pipe elevators suspend the drill pipe from a collar, which is formed around one end of the pipe and does not clamp the pipe, thereby permitting rotational pipe movement in order to threadably engage the same to the drill string.
A prior art technique for moving joints of casing from racks adjacent to the drilling rig comprises tying a line from the rig onto one end of a selected casing joint on the rack. The line is raised by lifting the casing joint up a ramp leading to the rig platform. As the rope lifts the casing from the rack, the lower end of the casing swings across the platform in a dangerous manner. The danger increases when a floating system is used in connection with drilling. Because the rope is tied around the casing at one end thereof, the casing does not hang vertically, but rather tilts somewhat. A man working on a platform elevated above the rig floor must hold the top of the casing and straighten it out while the casing is threaded into the casing string which is suspended in the well bore by slips positioned on the rotary table.
It is desirable to be able to grip casing or pipe positioned on a rack adjacent a drilling well, move the same into vertical orientation over the well bore, and thereafter lower the same onto the string suspended in the well bore.
In the past, various devices have been created which mechanically move a pipe from a horizontal orientation to a vertical orientation such that the vertically-oriented pipe can be installed into the well bore. Typically, these devices have utilized several interconnected arms that are associated with a boom. In order to move the pipe, a succession of individual movements of the levers, arms, and other components of the boom must be performed in a coordinated manner in order to achieve the desired result. Typically, a wide variety of hydraulic actuators are connected to each of the components so as to carry out the prescribed movement. A complex control mechanism is connected to each of these actuators so as to achieve the desired movement. Advanced programing is required of the controller in order to properly coordinate the movements in order to achieve this desired result.
Unfortunately, with such systems, the hydraulic actuators, along with other components, can become worn with time. Furthermore, the hydraulic integrity of each of the actuators can become compromised over time. As such, small variations in each of the actuators can occur. These variations, as they occur, can make the complex mechanism rather inaccurate. The failure of one hydraulic component can exacerbate the problems associated with the alignment of the pipe in a vertical orientation. Adjustments of the programming are often necessary to as to continue to achieve the desired results. Fundamentally, the more hydraulic actuators that are incorporated into such a system, the more likely it is to have errors, inaccuracies, and deviations in the desired delivery profile of the tubular. Typically, very experienced and knowledgeable operators are required so as to carry out this pipe movement operation. This adds significantly to the cost associated with pipe delivery.
In the past, pipe handling apparatuses have not been used for the installation of casing. The problem associated with casing is that the threads of the casing are formed on an inner wall and on an outer wall at the ends of each of the casing sections. Whenever these threads are formed, the relatively thin wall thickness of the casing is further minimized. Additionally, great precision is required so as to properly thread the threads of one casing section within the threads of an adjacent casing section. The amount of accuracy required for the delivery of the casing by a pipe handling apparatus, in the past, has not been sufficient so as to achieve the desired degree of accuracy for the installation of the casing sections in their threaded connection. The improper installation of one casing section upon another casing section can potentially damage the threads associated with such casing sections. Additionally, in the past, the pipe handling apparatus could potentially damage the thin-walled casing sections during the delivery. As such, a need has developed to adapt a pipe handling apparatus so as to achieve the desired amount of accuracy for the installation of casing sections.
To address these problems and needs, U.S. application Ser. No. 11/923,451, filed on Oct. 24, 2007, discloses a pipe handling apparatus that has a boom pivotally movable between a first position and a second position, a riser assembly pivotally connected to the boom, an arm pivotally connected at one end to the first portion of the riser assembly and extending outwardly therefrom, a gripper affixed to an opposite end of the arm suitable for gripping a diameter of the pipe, a link pivotally connected to a second portion of the riser assembly and pivotable so as to move relative to the movement of the boom between the first and second positions, and a brace having one end pivotally connected to the boom and an opposite end pivotally connected to the arm between the ends of the arm. The riser assembly has a first portion extending outwardly at an obtuse angle with respect to the second portion.
The pipe handling apparatus delivers a pipe to a wellhead in the second position. Pipes can be of extraordinary lengths and weights. Once the pipe is connected to other pipe in the wellhead, the grippers of the pipe handling apparatus release the pipe. A problem associated with the pipe handling apparatus is that once the grippers release the pipe at the wellhead, the apparatus springs upwardly and away from the wellhead. This is due to the release of the massive weight of the pipe. This springback causes unnecessary stresses on the pipe handling apparatus and can cause structural damage to the apparatus, such as cracking and bending. Upon the release of the pipe, the grippers and the arm of the pipe handling apparatus can have a spring back of up to ten inches. In addition to creating unnecessary stresses on the apparatus, the springback can cause the pipe to be deflected at the wellhead. Moreover, the accuracy of the pipe handling apparatus decreases when this spring back occurs. Thus, there is a need to avoid the spring back and minimize the deflection of the apparatus that is caused by the release of the pipe at the wellhead. These problems also occur when casing is delivered to the wellhead by the pipe handling apparatus.
Various patents and patent applications relate to apparatus and methods for stiffening and improving the integrity of a pipe handling system. For example, U.S. patent application Ser. No. 12/013,979, filed on Jan. 14, 2008 by the present inventor, discloses a pre-loading system for a pipe handling apparatus in which a boom is pivotally mounted at one end to a skid and in which an arm is interconnected to an opposite end of the boom. The pre-loading system has a tensioning system with one end affixed to the arm and an opposite end fixedly mounted so as to apply tension to the arm when the arm has a load applied to an end of the arm opposite the boom. The tensioning system includes a first cable assembly having one end interconnected to the arm and an opposite end fixedly mounted, and a second cable assembly interconnected to the arm and having an opposite end fixedly mounted. The first and second cable assemblies extend from opposite sides of the arm.
U.S. patent application Ser. No. 11/923,451, filed on Oct. 24, 2007 by the present inventor, discloses a pipe handling apparatus that has a boom pivotally movable between a first position and a second position, a riser assembly pivotally connected to the boom, an arm pivotally connected at one end to the first portion of the riser assembly and extending outwardly therefrom, a gripper affixed to an opposite end of the arm suitable for gripping a diameter of the pipe, a link pivotally connected to the riser assembly and pivotable so as to move relative to the movement of the boom between the first and second positions, and a brace having a one end pivotally connected to the boom and an opposite end pivotally to the arm between the ends of the arm. The riser assembly has a first portion extending outwardly at an obtuse angle with respect to the second portion.
U.S. Pat. No. 3,177,944, issued on Apr. 13, 1965 to R. N. Knights, describes a racking mechanism for earth boring equipment that provides for horizontal storage of pipe lengths on one side of and clear of the derrick. This is achieved by means of a transport arm which is pivoted toward the base of the derrick for swing movement in a vertical plane. The outer end of the arm works between a substantially vertical position in which it can accept a pipe length from, or deliver a pipe length to, a station in the derrick, and a substantially horizontal portion in which the arm can deliver a pipe length to, or accept a pipe length from, a station associated with storage means on one side of the derrick.
U.S. Pat. No. 3,464,507, issued on Sep. 2, 1969 to E. L. Alexander et al., teaches a portable rotary pipe handling system. This system includes a mast pivotally mounted and movable between a reclining transport position to a desired position at the site drilling operations which may be at any angle up to vertical. The mast has guides for a traveling mechanism that includes a block movable up and down the mast through operation of cables reeved from the traveling block over crown block pulleys into a drawwork. A power drill drive is carried by the traveling block. An elevator for drill pipe is carried by an arm swingably mounted relative to the power unit. Power tongs, slips, and slip bushings are supported adjacent the lower end of the mast and adapted to have a drill pipe extend therethrough from a drive bushing connected to a power drive whereby the drill pipe is extended in the direction of the hole to be drilled.
U.S. Pat. No. 3,633,771, issued on Jan. 11, 1972 to Woolslayer et al., discloses an apparatus for moving drill pipe into and out of an oil well derrick. A stand of pipe is gripped by a strong back which is pivotally mounted to one end of a boom. The boom swings the strong back over the rotary table thereby vertically aligning the pipe stand with the drill string. When both adding pipe to and removing pipe from the drill string, all vertical movement of the pipe is accomplished by the elevator suspended from the traveling block.
U.S. Pat. No. 3,860,122, issued on Jan. 14, 1975 to L. C. Cernosek, describes an apparatus for transferring a tubular member, such as a pipe, from a storage area to an oil well drilling platform. The positioning apparatus includes a pipe positioner mounted on a platform for moving the pipe to a release position whereby the pipe can be released to be lowered to a submerged position. A loader is operably attached or associated with the platform and a positioner in order to move the pipe from a stored position to a transfer position in which the pipe is transferred to the positioner. The positioner includes a tower having a pipe track pivotally mounted thereon with pipe clamp assemblies which are adapted to receive a pipe length. The pipe track is pivotally movable by a hydraulic power mechanism or gear mechanism between a transfer position in which pipe is moved into the clamp assemblies and the release position in which the pipe is released for movement to a submerged position.
U.S. Pat. No. 3,986,619, issued on Oct. 19, 1976 to Woolslayer et al., shows a pipe handling apparatus for an oil well drilling derrick. An inner end of the boom is pivotally supported on a horizontal axis in front of a well. A clamping means is pivotally connected to the outer end of the boom on an axis parallel to the horizontal axis at one end. The clamping means allows the free end of the drill pipe to swing across the boom as the outer end of the boom is raised or lowered. A line is connected at one end with the traveling block that raises and lowers the elevators and at the other end to the boom so as to pass around sheaves.
U.S. Pat. No. 4,172,684, issued on Oct. 30, 1979 to C. Jenkins, shows a floor-level pipe handling apparatus which is mounted on the floor of an oil well derrick. The apparatus includes a support that is rockable on an axis perpendicular to the centerline of a well being drilled. One end of an arm is pivotally mounted on the support on an axis transverse to the centerline of the well. The opposite end of the arm carries a pair of shoes having laterally opening pipe-receiving seats facing away from the arm. The free end of the arm can be swung toward and away from the well centerline and the arm support can be rocked to swing the arm laterally.
U.S. Pat. No. 4,403,666, issued on Sep. 13, 1983 to C. A. Willis, shows self-centering tongs and a transfer arm for a drilling apparatus. The clamps of the transfer arm are resiliently mounted to the transfer arm so as to provide limited axial movement of the clamps and thereby of a clamped down hole tubular. A pair of automatic, self-centering, hydraulic tongs is provided for making up and breaking out threaded connections of tubulars.
U.S. Pat. No. 4,407,629, issued on Oct. 4, 1983 to C. A. Willis, teaches a lifting apparatus for downhole tubulars. This lifting apparatus includes two rotatably mounted clamps which are rotatable between a side-loading position so as to facilitate the loading and unloading in the horizontal position, and a central position, in which a clamped tubular is aligned with the drilling axis when the boom is in the vertical position. An automatic hydraulic sequencing circuit is provided to automatically rotate the clamps into the side-loading position whenever the boom is pivoted with a downhole tubular positioned in the clamp. In this position, the clamped tubular is aligned with a safety plate mounted on the boom to prevent a clamped tubular from slipping from the clamps.
U.S. Pat. No. 4,492,501, issued on Jan. 8, 1985 to Haney, provides a platform positioning system for a drilling operation which includes a support structure and a transfer arm pivotally connected to the support structure to rotate about a first axis. This platform positioning system includes a platform which is pivotally connected to the support structure to rotate about a second axis, and a rod which is mounted between the transfer arm and the platform. The position of the arm and platform axes and the length of the rod are selected such that the transfer arm automatically and progressively raises the platform to the raised position by means of the rod as the transfer arm moves to the raised position. The transfer arm automatically and progressively lowers the platform to the lowered position by means of the rod as the transfer arm moves to the lowered position.
U.S. Pat. No. 4,595,066, issued on Jun. 17, 1986 to Nelmark et al., provides an apparatus for handling drill pipes and used in association with blast holes. This system allows a drill pipe to be more easily connected and disconnected to a drill string in a hole being drilled at an angle. A receptacle is formed at the lower end of the carrier that has hydraulically-operated doors secured by a hydraulically operated lock. A gate near the upper end is pneumatically operated in response to the hydraulic operation of the receptacle lock.
U.S. Pat. No. 4,822,230, issued on Apr. 18, 1989 to P. Slettedal, teaches a pipe handling apparatus which is adapted for automated drilling operations. Drill pipes are manipulated between substantially horizontal and vertical positions. The apparatus is used with a top mounted drilling device which is rotatable about a substantially horizontal axis. The apparatus utilizes a strongback provided with clamps to hold and manipulate pipes. The strongback is rotatably connected to the same axis as the drilling device. The strong back moves up or down with the drilling device. A brace unit is attached to the strongback to be rotatable about a second axis.
U.S. Pat. No. 4,834,604, issued on May 30, 1989 to Brittain et al., provides a pipe moving apparatus and method for moving casing or pipe from a horizontal position adjacent a well to a vertical position over the well bore. The machine includes a boom movable between a lowered position and a raised position by a hydraulic ram. A strongback grips the pipe and holds the same until the pipe is vertically positioned. Thereafter, a hydraulic ram on the strong back is actuated thereby lowering the pipe or casing onto the string suspended in the well bore and the additional pipe or casing joint is threaded thereto.
U.S. Pat. No. 4,708,581, issued on Nov. 24, 1987 H. L. Adair, provides a method for positioning a transfer arm for the movement of drill pipe. A drilling mast and a transfer arm are mounted at a first axis adjacent the mast to move between a lowered position near ground level and an upper position aligned with the mast. A reaction point anchor is fixed with respect to the drilling mast and spaced from the first axis. A fixed length link is pivotally mounted to the transfer arm at a second axis, spaced from the first axis, and a first single stage cylinder is pivotally mounted at one end to the distal end of the link and at the other end to the transfer arm. A second single stage hydraulic cylinder is pivotably mounted at one end to the distal end of the link and at the other end to the reaction point.
U.S. Pat. No. 4,759,414, issued on Jul. 26, 1988 to C. A. Willis, provides a drilling machine which includes a drilling superstructure skid which defines two spaced-apart parallel skid runners and a platform. The platform supports a drawworks mounted on a drawworks skid and a pipe boom is mounted on a pipe boom skid sized to fit between the skid runners of the drilling substructure skid. The drilling substructure skid supports four legs which, in turn, support a drilling platform on which is mounted a lower mast section. The pipe boom skid mounts a pipe boom as well as a boom linkage, a motor, and a hydraulic pump adapted to power the pipe boom linkage. Mechanical position locks hold the upper skid in relative position over the lower skid.
U.S. Pat. No. 5,458,454, issued on Oct. 17, 1995 to R. S. Sorokan, describes a pipe handling method which is used to move tubulars used from a horizontal position on a pipe rack adjacent the well bore to a vertical position over the well center. This method utilizes bicep and forearm assemblies and a gripper head for attachment to the tubular. The path of the tubular being moved is close to the conventional path of the tubular utilizing known cable transfer techniques so as to allow access to the drill floor through the V-door of the drill rig. U.S. Pat. No. 6,220,807 describes an apparatus for carrying out the method of U.S. Pat. No. 5,458,454.
U.S. Pat. No. 6,609,573, issued on Aug. 26, 2003 to H. W. F. Day, teaches a pipe handling system for an offshore structure. The pipe handling system transfers the pipes from a horizontal pipe rack adjacent to the drill floor to a vertical orientation in a set-back area of the drill floor where the drill string is made up for lowering downhole. The cantilevered drill floor is utilized with the pipe handling system so as to save platform space.
U.S. Pat. No. 6,705,414, issued on Mar. 16, 2004 to Simpson et al., describes a tubular transfer system for moving pipe between a substantial horizontal position on the catwalk and a substantially vertical position at the rig floor entry. Bundles of individual tubulars are moved to a process area where a stand make-up/break-out machine makes up the tubular stands. The bucking machine aligns and stabs the connections and makes up the connection to the correct torque. The tubular stand is then transferred from the machine to a stand storage area. A trolley is moved into position over the pick-up area to retrieve the stands. The stands are clamped to the trolley and the trolley is moved from a substantially horizontal position to a substantially vertical position at the rig floor entry. A vertical pipe-racking machine transfers the stands to the traveling equipment. The traveling equipment makes up the stand connection and the stand is run into the hole.
U.S. Pat. No. 6,779,614, issued on Aug. 24, 2004 to M. S. Oser, shows another system and method for transferring pipe. A pipe shuttle is used for moving a pipe joint into a first position and then lifting upwardly toward an upper second position.
It is an object of the present invention to provide a system and method for preventing the spring back of a pipe handling apparatus when delivering a pipe to a wellhead.
It is another object of the present invention to provide a system and method for stiffening a pipe handling apparatus that minimizes the amount of calibration required in order to move the pipe from a horizontal orientation to a vertical orientation.
It is another object of the present invention to provide a system and method for stiffening a pipe handling apparatus that operates within a single degree of freedom so as to move the pipe without adjustments between the components.
It is still another object of the present invention to provide a system and method for stiffening a pipe handling apparatus that utilizes an existing derrick.
It is another object of the present invention to provide a system and method for stiffening a pipe handling apparatus that prevents damages of the components of the pipe handling apparatus.
It is another object of the present invention to provide a system and method for stiffening a pipe handling apparatus that prevents sideways motions of the pipe handling apparatus caused by wind.
It is another object of the present invention to provide a system and method for stiffening that achieves greater precision in the delivery and installation of pipe and/or casing.
It is another object of the present invention to provide a system and method for stiffening a pipe handling apparatus that increases the structural stiffness of the system.
These and other objects and advantages of the present invention will become apparent from a reading of the attached specification and appended claims.

This patent is subject to a terminal disclaimer.

Header structure for a pipe handling apparatus


A mechanical seal provides bi-directional sealing and comprising a body in hybrid material, being structured in a component of elastomeric material and a component of segmented or non-segmented composite material distributed in a lagged way along said body. The seal is resistant to extrusion failure at high differential pressures, which facilitates its installation in several equipment elements, such as underwater or ground.

As is well known in the art, the mechanical seal was developed by George Cook in the early 20th century, originally called "Cook Seal", and was applied in cooling compressors. Since then there have been improvements due to the demand for seals working at different pressure levels and different mechanisms. Due to this fact, several materials are until now studied and applied to obtain increasingly better results for this mechanical element.
In the oil and gas sector, several types of elastomeric seals are used, which may or may not include reinforcements. Such reinforcements may be obtained either by the addition of other materials to the elastomeric compound or by using one or more additional parts to the elastomeric seal, said parts being metallic, ceramic, polymeric or any other material with several geometries, in order to reinforce the seal and withstand higher differential pressures.
In addition to the variety of material types, there are several elastomeric seal geometries in order to reinforce their structure in a way to withstand higher pressure differentials. Examples of these seals are: O-ring, spring seal and lip seal. These seals have a very efficient behavior and are widely used for the sealing of several components, such as mechanical connectors, flanges, stabs, etc.
These seals are dependent on small dimensional tolerances, in the order of tenths of a millimeter diametrically, which are fundamental to ensure correct preloading and resistance to extrusion of the elastomeric material when subjected to a differential pressure. When these thresholds are exceeded, an elastomer extrusion occurs and the consequent unfeasibility of the seal.
Current elastomeric seals are classified into three groups: elastomeric seals with a single material, for example O-rings; bicomponent elastomeric seals, for example elastomeric ring combined with anti-extrusion ring; and elastomeric seals with more than one material in a single component, for example the lip seal, spring seal.
Single-material elastomeric seals have very limited extrusion strength and are suitable for working with small dimensional tolerances, since they do not have any special anti-extrusion mechanism. The hardening of the elastomer as a mitigating action to avoid extrusion failure compromises the ability to deform at low pressures and to promote sealing. Historically, such seals even in restricted dimensional tolerances do not withstand differential pressures greater than 5,000 psi.
Bicomponent seals, on the other hand, have superior sealing strength at larger clearances and higher pressures. However, the use of a second anti-extrusion component in addition to having assembly limitations does not allow for clearance of the order of a few millimeters, since many of them are made of polymeric materials. Other materials, for example metallic, in turn, compromise the assembly and its dynamic applications due to the risk of scratching the sealing areas.
Finally, seals with more than one material fill a space by combining rubber with other materials. However, such seals have high restrictions on assembly in external and internal diameters due to the restriction imposed by using more resistant materials. In the case of metallic materials, these can damage the sealing areas in case of ndynamic applications. In all current systems, the operating mechanism of these sealing rings seeks a balance between the seal material elastic deformation, which is important for sealing, the small dimensional component clearances which is important for extrusion strength, and elastic deformation required for assembling in several diameters.
US2015233371, US2005167928 and U.S. Pat. No. 5,791,657 disclose mechanical seals of the closest prior art to the present invention as they disclose seals which have sealing and anti-extrusion elements. However, the combination of high dimensional clearance, assembly and high differential pressure cannot be supported by existing elastomeric seals, whether with or without reinforcements.
The above mentioned mechanical seals have as main limitations the combination of certain factors, such as, for example, the dimensional clearances necessary to avoid extrusion failure of the elastomeric material, typically limited to a maximum of tenths of a millimeter, and the ability to deform for assembly in machined housings at external and internal diameters, restricting the options of reinforcements, which, because they are required to accept high elastic deformation, do not present high mechanical strength to withstand pressure differentials in the order of tens of thousands of psi, for example 20,000 psi.
The present invention therefore provides for the correction of the above problems for the mechanical seals of the prior art, which will evidently result in a significant increase in efficiency in relation to the sealing and anti-extrusion due to the pressure differential, effects of which have long been searched by those skilled in the art.

Mechanical seal for bidirectional sealing


A method for correcting for defects in a digital image taken by an image sensor when there are pre-existing defects in two pixels in adjacent columns of the image sensor which causes two adjacent lines of pixels in the digital image to have corrupted data.

The present invention relates to correcting for corrupted data in a digital image caused by defective pixels in an image sensor.
In certain types of image sensors, when there is a defect in two pixels of such sensor it causes two adjacent lines of pixels in a digital image to have corrupt data. This happens during the transfer of electrons corresponding to pixels when such electrons are transferred through the defective pixel. An example of this situation is a full frame image sensor. In a typical full frame image sensor after an image is captured, electrons stored in the pixels of such sensor are transferred a line at a time through the pixels of the image sensor. A defective pixel will corrupt data stored in the electrons of subsequent pixels which pass throught it. This causes a line of corrupted pixel data. In a full frame image sensor, a column defect is an anomaly in the structure of an image sensor that prevents the vertical transfer of pixel charge packets. As a consequence, none of the affected pixels in the adjacent columns of defective pixels can provide valid image information. If left untreated, this condition would produce a partial height or a full height adjacent vertical lines of artifacts running through the image. The current method of concealing a column defect is to average nearest horizontal neighbors of the same filter type. In a standard color filter array (CFA), for example, the Bayer CFA pattern shown in commonly-assigned U.S. Pat. No. 3,971,065, that means averaging the pixel two positions to the left with the pixel two positions to the right. While this method works well enough for the vast majority of pixels, it fails to properly handle corrupted pixels in certain image contexts, such as high contrast diagonal edges. In addition, when the current method fails, it doesn""t fail gracefully, but rather with opposing vertical spikes of spurious color.
It is an object of the present invention to provide an improved method for correcting for two adjacent lines of corrupted data in a digital image formed by an image sensor with defective pixels.
It is another object of the present invention to provide a method which is particularly suited for correcting for adjacent column defects in a full frame image sensor and that works effectively for a variety of scene content including high contrast diagonal edges.
These objects are achieved in a method for correcting for defects in a digital image taken by an image sensor when there are pre-existing defects in two pixels in adjacent columns of the image sensor which causes two adjacent lines of pixels in the digital image to have corrupted data, comprising the steps of:
(a) providing a defect map which identifies the position of the defective pixels and specifies the two adjacent lines of pixels which during readout will be caused to have corrupted data;
(b) capturing the digital image in the image sensor and reading out such digital image to provide the digital image with the two adjacent lines of pixels in the digital image having corrupted data;
(c) computing classifiers based on adjacent non-corrupted pixel data which indicate that there is a horizontal edge or a diagonal edge feature which passes through the defective lines of pixels; and
(d) adaptively replacing the data in the corrupted image pixels by selecting an algorithm which correponds to the edge feature identified by the classifier and using the valid data in the neighboring non-corrupted pixels of the selected edge feature.
It is an advantage of the present invention to provide a concealment algorithm for correcting for corruption in two adjacent lines of pixel data caused by defective pixels in an image sensor such as a full frame image sensor. This algorithm significantly improves the efficacy of correcting for a line of corrupted pixel data over a wide range of scene content.

Correcting for defects in a digital image taken by an image sensor caused by pre-existing defects in two pixels in adjacent columns of an image sensor


Compounds of formulae (IA) and (IB) or pharmaceutically or veterinarily acceptable salts thereof, or pharmaceutically or veterinarily acceptable solvates of either entity, wherein R1 is C1 to C3 alkyl substituted with C3 to C6 cycloalkyl, CONR5R6 or a N-linked heterocyclic group; (CH2)nHet or (CH2)nAr; R2 is C1 to C6 alkyl; R3 is C1 to C6 alkyl optionally substituted with C1 to C4 alkoxy; R4 is SO2NR7R8; R5 and R6 are each independently selected from H and C1 to C4 alkyl optionally substituted with C1 to C4 alkoxy, or, together with the nitrogen atom to which they are attached, form a 5- or 6-membered heterocyclic group; R7 and R8, together with the nitrogen atom to which they are attached, form a 4-R10-piperazinyl group; R10 is H or C1 to C4 alkyl optionally substituted with OH, C1 to C4 alkoxy or CONH2; H is an optionally substituted C-linked 5- or 6-membered heterocyclic group; Ar is optionally substituted phenyl; and n is 0 or 1; are potent and selective cGMP PDE5 inhibitors useful in the treatment of, inter alia, male erectile dysfunction and female sexual dysfunction.

This invention relates to a series of pyrazolo[4,3-d]pyrimidin-7-ones, which inhibit cyclic guanosine 3xe2x80x2,5xe2x80x2-monophosphate phosphodiesterases (cGMP PDEs). More notably, the compounds of the invention are potent and selective inhibitors of type 5 cyclic guanosine 3xe2x80x2,5xe2x80x2-monophosphate phosphodiesterase (cGMP PDE5) and have utility therefore in a variety of therapeutic areas.
In particular, the compounds are of value in the treatment of male erectile dysfunction (MED) and female sexual dysfunction (FSD) but, clearly, will be useful also for treating other medical conditions for which a potent and selective cGMP PDE5 inhibitor is indicated. Such conditions include premature labour, dysmenorrhoea, benign prostatic hyperplasia (BPH), bladder outlet obstruction, incontinence, stable, unstable and variant (Prinzmetal) angina, hypertension, pulmonary hypertension, congestive heart failure, atherosclerosis, conditions of reduced blood vessel patency e.g. post-percutaneous transluminal coronary angioplasty (post-PTCA), peripheral vascular disease, stroke, bronchitis, allergic asthma, chronic asthma, allergic rhinitis, glaucoma and diseases characterised by disorders of gut motility, e.g. irritable bowel syndrome (IBS).
WO-A-94/28902 and WO-A-96/16644 relate to the use of various series of cGMP PDE inhibitors for the treatment of MED including, within the latter, the compounds disclosed in EP-A-020188 which are also adenosine receptor antagonists and reported to be useful in the treatment of cardiovascular disorders as well as the compounds disclosed in EP-A-0352960 which have bronchodilator, vasodilator and anti-allergic properties.
Thus the invention provides compounds of formulae (IA) and (IB):
or a pharmaceutically or veterinarily acceptable salt thereof, or a pharmaceutically or veterinarily acceptable solvate of either entity,
wherein R1 is C1 to C3 alkyl substituted with C3 to C6 cycloalkyl, CONR5R6 or a N-linked heterocyclic group selected from pyrazolyl, imidazolyl, triazolyl, pyrrolidinyl, piperidinyl, morpholinyl and 4-R9-piperazinyl; (CH2)nHet or (CH2)nAr;
R2 is C1 to C6 alkyl;
R3 is C1 to C6 alkyl optionally substituted with C1-C4 alkoxy;
R4 is SO2NR7R8;
R5 and R6 are each independently selected from H and C1 to C4 alkyl optionally substituted with C1 to C4 alkoxy, or, together with the nitrogen atom to which they are attached, form a pyrrolidinyl, piperidinyl, morpholinyl or 4-R9-piperazinyl group;
R7 and R8, together with the nitrogen atom to which they are attached, form a 4-R10-piperazinyl group;
R9 is C1 to C4 alkyl;,
R10 is H or C1 to C4 alkyl optionally substituted with OH, C1 to C4 alkoxy or CONH2;
Het is a C-linked 6-membered heterocyclic group containing one or two nitrogen atoms, optionally in the form of its mono-N-oxide, or a C-linked 5-membered heterocyclic group containing from one to four heteroatoms selected from nitrogen, oxygen and sulphur, wherein either of said heterocyclic groups is optionally substituted with one or two substituents selected from C1 to C4 alkyl optionally substituted with C1 to C4 alkoxy, C1 to C4 alkoxy, halo and NH2,
Ar is phenyl optionally substituted with one or two substituents selected from C1 to C4 alkyl, C1 to C4 alkoxy, halo, CN, CONH2, NO2, NH2, NHSO2 (C1 to C4 alkyl) and SO2NH2;
and n is 0 or 1.
In the above definition, unless otherwise indicated, alkyl and alkoxy groups having three or more carbon atoms may be straight chain or branched chain. Halo means fluoro, chloro, bromo or iodo.
The compounds of formulae (IA) and (IB) may contain one or more chiral centres and therefore can exist as stereoisomers, i.e. as enantiomers or diastereoisomers, as well as mixtures thereof. The invention includes both the individual stereoisomers of the compounds of formulae (IA) and (IB) and any mixture thereof. Separation of diastereoisomers may be achieved by conventional techniques, e.g. by fractional crystallisation or chromatography (including HPLC) of a diastereoisomeric mixture of a compound of formula (IA) or (IB) or a suitable salt or derivative thereof. An individual enantiomer of a compound of formula (IA) or (IB) may be prepared from a corresponding optically pure intermediate or by resolution, either by HPLC of the racemate using a suitable chiral support or, where appropriate, by fractional crystallisation of the diastereoisomeric salts formed by reaction of the racemate with a suitable optically active acid or base.
The compounds of formulae (IA) and (IB) may also exist in tautomeric forms and the invention includes both mixtures thereof and the individual tautomers.
Also included in the invention are radiolabelled derivatives of compounds of formulae (IA) and (IB) which are suitable for biological studies.
The pharmaceutically or veterinarily acceptable salts of the compounds of formulae (IA) and (IB) which contain a basic centre are, for example, non-toxic acid addition salts formed with inorganic acids such as hydrochloric, hydrobromic, sulphuric and phosphoric acid, with organo-carboxylic acids, or with organo-sulphonic acids. Compounds of formulae (IA) and (IB) can also provide pharmaceutically or veterinarily acceptable metal salts, in particular non-toxic alkali metal salts, with bases. Examples include the sodium and potassium salts.
A preferred salt is the citrate.
A preferred group of compounds of formulae (IA) and (IB) is that wherein R1 is C1 to C2 alkyl substituted with C3 to C5 cycloalkyl, CONR5R6 or a N-linked heterocyclic group selected from pyrazolyl, triazolyl, morpholinyl and 4-R9-piperazinyl; (CH2)nHet or (CH2)nAr; R5 is H and R6 is C1 to C4 alkyl optionally substituted with C1 to C4 alkoxy or R5 and R6, together with the nitrogen atom to which they are attached, form a morpholinyl group; Het is selected from pyridinyl, 1-oxidopyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl, imidazolyl, isoxazolyl, triazolyl, triazolyl and oxadiazolyl, any of which is optionally substituted with one or two substituents selected from CH3, CH2CH2OCH3, OCH3 and NH2; and R2, R3, R4, R9, Ar and n are as previously defined.
A more preferred group of compounds of formulae (IA) and (IB) is that wherein R1 is C1 to C2 alkyl substituted with cyclobutyl, CONR5R6, pyrazol-1-yl, 1,2,3-triazol-1-yl, 1,2,4-triazol-1-yl, morpholin-4-yl or 4-methylpiperazin-1-yl; pyrimidin-2-yl; CH2Het or (CH2)nAr; R2 is C1 to C3 alkyl; R3 is C1 to C3 alkyl optionally substituted with C1 to C2 alkoxy; R5 is H and R6 is C1 to C2 alkyl optionally substituted with C1 to C2 alkoxy or R5 and R6, together with the nitrogen atom to which they are attached, form a morpholin-4-yl group; R10 is C1 to C2 alkyl optionally monosubstituted with OH, OCH3 or CONH2; Het is selected from pyridin-2-yl, 1-oxidopyridin-2-yl, pyridin-3-yl, pyridazin-3-yl, pyridazin-4-yl, pyrimidin-4-yl, pyrimidin-5-yl, pyrazin-2-yl, 3-methoxypyridin-2-yl, 6-aminopyridin-2-yl, 1-methylimidazol-2-yl, 3,5-dimethylisoxazol-4-yl, 2-methylthiazol-4-yl, 1-methyl-1,2,4-triazol-5-yl, 1-(2-methoxyethyl)-1,2,4-triazol-5-yl, 4-methyl-1,2,4-triazol-3-yl, 3-methyl-1,2,4-triazol-5-yl, 1,2,4-oxadiazol-3-yl and 5-methyl-1,2,4-oxadiazol-3-yl; Ar is selected from phenyl, 4-chlorophenyl, 4-bromophenyl, 2-cyanophenyl, 2-carbamoylphenyl, 4-carbamoylphenyl, 2-nitrophenyl, 4-nitrophenyl, 2-aminophenyl, 4-aminophenyl, 2-methanesulphonamidophenyl, 4-methanesulphonamidophenyl, 4-ethanesulphonamidophenyl, 4-(prop-2-ylsulphonamido)phenyl and 4-sulphamoylphenyl; and n is as previously defined.
A particularly preferred group of compounds of formulae (IA) and (IB) is that wherein R1 is cyclobutylmethyl, morpholin-4-ylcarbonylmethyl, 2-(morpholin-4-yl)ethyl, pyrimidin-2-yl, CH2Het or (CH2)nAr; R2 is CH2CH3 or CH2CH2CH3; R3 is CH2CH3, CH2CH2CH3 or CH2CH2OCH3; R10 is CH3, CH2CH3 or CH2CH2OH; Het is selected from pyridin-2-yl, pyridazin-3-yl, pyrazin-2-yl, 3-methoxypyridin-2-yl, 6-aminopyridin-2-yl, 1-methylimidazol-2-yl, 3,5-dimethylisoxazol-4-yl, 1-methyl-1,2,4-triazol-5-yl, 1-(2-methoxyethyl)-1,2,4-triazol-5-yl and 5-methyl-1,2,4-oxadiazol-3-yl; Ar is selected from phenyl, 2-aminophenyl, 2-methanesulphonamidophenyl, 4-methanesulphonamidophenyl, 4-ethanesulphonamidophenyl and 4-(prop-2-ylsulphonamido)phenyl; and n is as previously defined.
Especially preferred individual compounds of the invention include
5-{5-[4-(2-hydroxyethyl)piperazin-1-ylsulphonyl]-2-n-propoxyphenyl}-3-n-propyl-1-(pyridin-2-yl)methyl-1,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one;
1-(1-methylimidazol-2-yl)methyl-5-[5-(4-methylpiperazin-1-ylsulphonyl)-2-n-propoxyphenyl]-3-n-propyl-1,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one;
5-{5-[4-(2-hydroxyethyl)piperazin-1-ylsulphonyl]-2-n-propoxyphenyl}-3-n-propyl-2-(pyridin-2-yl)methyl-2,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one;
5-[5-(4-ethylpiperazin-1-ylsulphonyl)-2-n-propoxyphenyl]-3-n-propyl-2-(pyridin-2-yl)methyl-2,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one;
3-ethyl-5-[5-(4-ethylpiperazin-1-ylsulphonyl)-2-n-propoxyphenyl]2-(pyridin-2-yl)methyl-2,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one;
5-[5-(4-ethylpiperazin-1-ylsulphonyl)-2-n-propoxyphenyl]-3-n-propyl-2-(pyridazin-3-yl)methyl-2,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one;
5-[5-(4-ethylpiperazin-1-ylsulphonyl)-2-n-propoxyphenyl]-3-n-propyl-2-(pyrazin-2-yl)methyl-2,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one; and
5-[2-ethoxy-5-(4-ethylpiperazin-1-ylsulphonyl)phenyl]-3-n-propyl-2-(pyridin-2-yl)methyl-2,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one.
In a further aspect, the present invention provides processes for the preparation of compounds of formulae (IA) and (IB), their pharmaceutically and veterinarily acceptable salts, and pharmaceutically and veterinarily acceptable solvates of either entity, as illustrated below.
It will be appreciated by persons skilled in the art that, within certain of the processes described, the order of the synthetic steps employed may be varied and will depend inter alia on factors such as the nature of other functional groups present in a particular substrate, the availability of key intermediates and the protecting group strategy (if any) to be adopted. Clearly, such factors will also influence the choice of reagent for use in the said synthetic steps.
Illustrative of protecting group strategies are the routes to the syntheses of Example 56 in which alcohol protection using a t-butyldimethylsilyl group precedes the desired N-mesylation step, Example 63 in which the piperazine 4-position is Boc(t-butoxycarbonyl)-protected to preclude bis-sulphonylation of the piperazine, and Examples 23 and 68 in which amine protection using a pivaloyl group precedes the penultimate chlorosulphonation step.
It will also be appreciated that various standard substituent or functional group interconversions and transformations within certain compounds of formulae (IA) and (IB) will provide other compounds of formulae (IA) and (IB). Examples include alkoxide exchange at the 2-position of the 5-phenyl substituent (see conversion of Example 41 to Example 42), hydrolysis of cyano to carbamoyl (see conversion of Example 46 to Example 47), reduction of nitro to amino (see conversions of Examples 49, 50, 51, 91, 115, 118 and 121 to Examples 52, 53, 54, 93, 116, 119 and 122 respectively), sulphonylation of amino (see conversions of Examples 52, 54, 116, 119 and 122 to Examples 55, 57, 117, 120, and 123 and 124 respectively), hydrogenolysis of halo (see conversion of Example 88 to Example 87) and N-oxidation of pyridinyl (see conversions of Examples 6 and 12 to Examples 128 and 129 respectively).
Moreover, certain compounds of formulae (IA) and (IB) may be prepared directly from the corresponding 4-unsubstituted piperazine analogues, that is compounds of formulae (IA) and (IB) wherein R10 is hydrogen, using standard alkylation procedures.
The following processes are illustrative of the general synthetic procedures which may be adopted in order to obtain the compounds of the invention.
1. A compound of formula (IA) or (IB) may be prepared from a compound of formula (IIA) or (IIB) respectively:
wherein Y is halo, preferably chloro, and R1, R2 and R3 are as previously defined for formulae (IA) and (IB), by reaction with a compound of formula (III):
R7R8NHxe2x80x83xe2x80x83(III)
wherein R7 and R8 are as previously defined for formulae (IA) and (IB).
The reaction is generally conducted at room temperature, preferably in the presence of an appropriate solvent such as a C1 to C3 alkanol, using an excess of (III) or other suitable base to scavenge the acid by-product (HY).
A compound of formula (IIA) or (IIB) may be prepared from a compound of formula (IVA) or (IVB) respectively:
wherein R1, R2 and R3 are as previously defined for formulae (IIA) and (IIB), by the application of known methods for the introduction of a SO2Y group, wherein Y is also as previously defined for formulae (IIA) and (IIB), into an aromatic ring system. For example, when Y is chloro, by the action of excess chlorosulphonic acid, optionally followed by excess thionyl chloride, at from about 0xc2x0 C. to about room temperature.
A compound of formula (IVA) or (IVB) may be prepared by alkylation of a compound of formula (V):
wherein R2 and R3 are as previously defined for formulae (IVA) and (IVB), using one or more of a plethora of well-known methods, such as:
(i) reaction of (V) with a compound of formula R1X, wherein R1 is as previously defined for formulae (IVA) and (IVB), and X is a suitable leaving group, e.g. halo (preferably chloro, bromo or iodo), C1-C4 alkanesulphonyloxy, trifluoromethanesulphonyloxy or arylsulphonyloxy (such as benzenesulphonyloxy or p-toluenesulphonyloxy), in the presence of an appropriate base, optionally in the presence of sodium iodide or potassium iodide, at from about xe2x88x9270xc2x0 C. to about 100xc2x0 C. Preferably the alkylation is conducted at from about room temperature to about 80xc2x0 C.
Suitable base-solvent combinations may be selected from
(a) sodium, potassium or cesium carbonate, sodium or potassium bicarbonate, or a tertiary amine such as triethylamine or pyridine, together with a C1 to C4 alkanol, 1,2-dimethoxyethane, tetrahydrofuran, 1,4-dioxan, acetonitrile, pyridine, dimethylformamide or N,N-dimethylacetamide;
(b) sodium or potassium hydroxide, or a sodium or potassium C1 to C4 alkoxide, together with a C1 to C4 alkanol, water or mixtures thereof;
(c) lithium, sodium or potassium hydride, lithium, sodium or potassium bis(trimethylsilyl)amide, lithium diisopropylamide or butyllithium, together with toluene, ether, 1,2-dimethoxyethane, tetrahydrofuran or 1,4-dioxan; or
(d) under phase transfer catalysis conditions, a tetraalkylammonium halide or hydroxide, together with a mixture of an aqueous solution of sodium or potassium hydroxide and dichloromethane, 1,2-dichloroethane or chloroform;
(ii) reaction of (V) with a compound of formula R1OH, wherein R1 is as previously defined for formulae (IVA) and (IVB), using classical Mitsunobu methodology. Typical reaction conditions involve treating (V) with the alkanol in the presence of a triarylphosphine and a di(C1 to C4)alkyl azodicarboxylate, in a suitable solvent such as tetrahydrofuran or 1,4-dioxan, at from about xe2x88x925xc2x0 C. to about room temperature.
Certain compounds of formulae (IVA) and (IVB) may be obtained less directly from related analogues, when these are more readily accessible, using the alkylation methods previously described: see, for example, the hydrogenolytic transformation of Preparation 33, wherein R1 is 2,4-dichloropyrimidin-5-ylmethyl, to Preparation 34, wherein R1 is pyrimidin-5-ylmethyl. Similarly, the amides of Preparations 102, 103 and 104 and of Preparations 105, 106 and 107 are obtained from the corresponding carboxylic acids of Preparations 101 and 69 respectively.
Other compounds of formulae (IVA) and (IVB), wherein R1 is CH2Het, may be prepared by construction of the heterocyclic ring subsequent to the pyrazolopyrimidinone-alkylation step. This approach is particularly convenient when the required HetCH2X is relatively inaccessible. For example, when Het is either 3-methyl-1,2,4-triazol-5-yl or 5-methyl-1,2,4-oxadiazol-3-yl, the heterocyclic rings can be assembled from a carboxymethyl precursor and a cyanomethyl precursor respectively, i.e. a compound of formula (IVA) and (IVB) wherein R1 is CH2CO2H or CH2CN, by a series of conventional steps. Each alternative is illustrated by the transformations of Preparation 69 to Preparation 72 and of Preparations 73 and 77 to Preparations 76 and 79.
Yet another variation for obtaining a compound of formula (IVA) or (IVB) is to incorporate the R1 group at a much earlier stage in the synthetic pathway, e.g. by generating a suitably N1- or N2-alkylated pyrazole derivative, which is then processed to (IVA) or (IVB) by analogy with the subsequently described conversion of (VII) to (V).
A compound of formula (V) may be obtained from a compound of formula (VI):
wherein R2 and R3 are as previously defined for formula (V), by the application of known cyclisation methods for pyrimidinone ring formation. Thus, for example, the cyclisation may be effected by the treatment of (V) with a base such as sodium or potassium hydroxide, or sodium or potassium carbonate, optionally in the presence of hydrogen peroxide, in a C1 to C4 alkanol-water medium at from about 60xc2x0 C. to the reflux temperature of the reaction mixture.
The cyclisation may also be mediated by a sodium or potassium C1 to C5 alkoxide, in a C1 to C5 alkanol as solvent, at from about 60xc2x0 C. to the reflux temperature of the reaction mixture.
Alternative cyclisation procedures include the treatment of (V) with either polyphosphoric acid at from about 130 to about 150xc2x0 C. or with a Lewis acid, e.g. anhydrous zinc chloride at from about 200 to about 220xc2x0 C.
A compound of formula (VI) may be obtained by selective N-acylation of a compound of formula (VII):
wherein R2 is as previously defined for formula (VI), with a compound of formula (VIII):
wherein Y is a suitable leaving group, and R3 is as previously defined for formula (VI). For example, when Y is chloro, the reaction may be conducted with the appropriate aroyl chloride in the presence of an excess of a tertiary amine such as triethylamine or pyridine to act as scavenger for the acid by-product (HY), optionally in the presence of a catalyst such as 4-dimethylaminopyridine, in a suitable solvent such as dichloromethane, at from about 0xc2x0 C. to about room temperature. For convenience, pyridine may also be used as the solvent.
2. An alternative, generally applicable, synthetic route to compounds of formulae (IA) and (IB) involves the incorporation of the R4 substituent at an earlier stage of the synthesis.
Thus a compound of formula (IA) or (IB) may be prepared by cyclisation of a compound of formula (IXA) or (IXB) respectively:
wherein R1, R2, R3 and R4 are as previously defined for formulae (IA) and (IB). The cyclisation may be effected under basic, neutral or acidic conditions.
Under neutral conditions, a compound of formula (IXA) or (IXB) may be heated, optionally in the presence of a solvent and/or optionally in the presence of a dehydrating agent and/or mechanical water-removal system, e.g. a Dean-Stark apparatus. A suitable solvent is 1,2-dichlorobenzene, sulpholane or N-methylpyrrolidin-2-one, a suitable dehydrating agent is molecular sieves and, preferably, the reaction is carried out at from 180 to 220xc2x0 C.
Under acidic conditions, the cyclisation may be carried out by reaction of a compound of formula (IXA) or (IXB) with a protic acid or Lewis acid, optionally in the presence of a solvent. A suitable protic acid is concentrated sulphuric acid, phosphoric acid or p-toluenesulphonic acid, a suitable Lewis acid is boron trifluoride, aluminium chloride, silicon tetrachloride, stannic chloride, titanium tetrachloride, ferric chloride or zinc chloride, a suitable solvent is glacial acetic acid, tetrahydrofuran, 1,4-dioxan or chlorobenzene and, preferably, the reaction is carried out at from 65 to 210xc2x0 C.
However, the preferred mode of cyclisation of a compound of formula (IXA) or (IXB) is under basic conditions, preferably in a solvent, optionally in the presence of hydrogen peroxide or a peroxide salt, and is followed, where necessary, by neutralisation of the reaction mixture. A suitable base is selected from the group consisting of the C1-C12 alkoxide and hydride salts of lithium, sodium and potassium, sodamide, sodium cyclohexylamide and cesium carbonate, the quantity of base employed is from 1.1 to 2.0 molecular equivalents, a suitable solvent is selected from the group consisting of ethanol, n-propanol, t-butanol, t-amyl alcohol, 1-methylcyclohexanol, tetrahydrofuran and 1,4-dioxan, and the reaction is carried out at from 60 to 105xc2x0 C.
Preferably the base is selected from the group consisting of sodium ethoxide, sodium t-butoxide, potassium t-butoxide and sodium hydride; and the solvent is selected from the group consisting of ethanol, n-propanol, t-butanol, t-amyl alcohol and tetrahydrofuran.
A compound of formula (IXA) or (IXB) may be prepared by reaction of a compound of formula (XA) or (XB) respectively:
wherein R1 and R2 are as previously defined for formulae (IXA) and (IXB) with a compound of formula (XI):
wherein R3 and R4 are also as previously defined for formulae (IXA) and (IXB).
The coupling reaction may be achieved using conventional amide bond-forming techniques, e.g. via the acyl chloride derivative of (XI), by analogy with the preparation of a compound of formula (VI), ensuring that any potentially vulnerable substituent (for example when R10 is C1 to C4 alkyl substituted with OH or CONH2) is appropriately protected.
In particular, any one of a host of amino acid coupling variations may be used. For example, the acid of formula (XI) may be activated using a carbodiimide such as 1,3-dicyclohexylcarbodiimide or 1-ethyl-3-(3-dimethylaminoprop-1-yl)carbodiimide optionally in the presence of 1-hydroxybenzotriazole and/or a catalyst such as 4-dimethylaminopyridine, or by using a halotrisaminophosphonium salt such as bromotris(pyrrolidino)phosphonium hexafluorophosphate. Either type of coupling is conducted in a suitable solvent such as dichloromethane, optionally in the presence of a tertiary amine such as N-methylmorpholine or N-ethyldiisopropylamine (for example when either the compound of formula (XA) or (XB), or the activating reagent, is presented in the form of an acid addition salt), at about 0xc2x0 C. Preferably, from 1.1 to 2.0 molecular equivalents of the activating reagent and from 2.0 to 3.0 molecular equivalents of any tertiary amine present are employed.
Preferably, a mixture of (XI) and either (XA) or (XB) is treated with about one molecular equivalent of the coupling reagent (benzotriazol-1-yloxy)tripyrrolidinophosphonium hexafluorophosphate (PyBOP) in a suitable solvent such as dimethylformamide at about room temperature.
In a further variation, the carboxylic acid function of (XI) may first of all be activated using up to about a 5% excess of a reagent such as N,Nxe2x80x2-carbonyldiimidazole in a suitable solvent, e.g. ethyl acetate or butan-2-one, at from about room temperature to about 80xc2x0 C., followed by reaction of the intermediate imidazolide with either (XA) or (XB) at from about 20 to about 90xc2x0 C.
The amines of formula (III), the 4-aminopyrazole-5-carboxamides of formulae (VII), (XA) and (XB), the carboxylic acid derivatives of formula (VIII) and the carboxylic acids of formula (XI), when neither commercially available nor subsequently described, can be obtained either by analogy with the processes described in the Preparations section or by conventional synthetic procedures, in accordance with standard textbooks on organic chemistry or literature precedent, from readily accessible starting materials using appropriate reagents and reaction conditions.
Moreover, persons skilled in the art will be aware of variations of, and alternatives to, those processes described hereinafter in the Examples and Preparations sections which allow the compounds defined by formulae (IA) and (IB) to be obtained.
The pharmaceutically acceptable acid addition salts of the compounds of formulae (IA) and (IB) which contain a basic centre may also be prepared in a conventional manner. For example a solution of the free base is treated with the appropriate acid, either neat or in a suitable solvent, and the resulting salt isolated either by filtration of by evaporation under vacuum of the reaction solvent. Pharmaceutically acceptable base addition salts can be obtained in an analogous manner by treating a solution of a compound of formula (IA) or (IB) with the appropriate base. Both types of salt may be formed or interconverted using ion-exchange resin techniques.
The biological activities of the compounds of the present invention were determined by the following test methods.
In vitro PDE inhibitory activities against cyclic guanosine 3xe2x80x2,5xe2x80x2-monophosphate (cGMP) and cyclic adenosine 3xe2x80x2,5xe2x80x2-monophosphate (cAMP) phosphodiesterases were determined by measurement of their IC50 values (the concentration of compound required for 50% inhibition of enzyme activity).
The required PDE enzymes were isolated from a variety of sources, including human corpus cavernosum, human and rabbit platelets, human cardiac ventricle, human skeletal muscle and bovine retina, essentially by the method of W. J. Thompson and M. M. Appleman (Biochem., 1971, 10, 311). In particular, the cGMP-specific PDE (PDE5) and the cGMP-inhibited cAMP PDE (PDE3) were obtained from human corpus cavernosum tissue, human platelets or rabbit platelets; the cGMP-stimulated PDE (PDE2) was obtained from human corpus cavernosum; the calcium/calmodulin (Ca/CAM)-dependent PDE (PDE1) from human cardiac ventricle; the cAMP-specific PDE (PDE4) from human skeletal muscle; and the photoreceptor PDE (PDE6) from bovine retina.
Assays were performed using a modification of the xe2x80x9cbatchxe2x80x9d method of W. J. Thompson et al. (Biochem., 1979, 18, 5228). Results from these tests show that the compounds of the present invention are potent and selective inhibitors of cGMP-specific PDE5.
This was assessed in vitro by determining the capactiy of a compound of the invention to enhance sodium nitroprusside-induced relaxation of pre-contracted rabbit corpus cavernosum tissue strips, as described by S. A. Ballard et al. (Brit. J. Pharmacol., 1996, 118 (suppl.), abstract 153P).
Compounds were screened in anaesthetised dogs to determine their capacity, after i.v. administration, to enhance the pressure rises in the corpora cavernosa of the penis induced by intracavernosal injection of sodium nitroprusside, using a method based on that described by Trigo-Rocha et al. (Neurourol. and Urodyn., 1994, 13, 71).
In human therapy, the compounds of formulae (IA) and (IB), their pharmaceutically acceptable salts, and pharmaceutically acceptable solvates of either entity, can be administered alone, but will generally be administered in admixture with a pharmaceutical carrier selected with regard to the intended route of administration and standard pharmaceutical practice. Preferably, they are administered orally in the form of tablets containing such excipients as starch or lactose, or in capsules or ovules either alone or in admixture with excipients, or in the form of elixirs, solutions or suspensions containing flavouring or colouring agents. They can also be injected parenterally, for example intracavernosally, intravenously, intramuscularly or subcutaneously. For parenteral administration, they are best used in the form of a sterile aqueous solution which may contain other substances, for example enough salts or monosaccharides to make the solution isotonic with blood. For buccal or sublingual administration they may be administered in the form of tablets or lozenges which can be formulated in a conventional manner.
For oral, parenteral, buccal and sublingual administration to patients, the daily dosage level of the compounds of formulae (IA) and (IB) and their pharmaceutically acceptable salts and solvates may be from 10 to 500 mg (in single or divided doses). Thus, for example, tablets or capsules may contain from 5 to 100 mg of active compound for administration singly, or two or more at a time, as appropriate. The physician in any event will determine the actual dosage which will be most suitable for an individual patient and it will vary with the age, weight and response of the particular patient. The above dosages are exemplary of the average case; there can, of course, be individual instances where higher or lower dosage ranges are merited and such are within the scope of this invention.
Generally, in humans, oral administration of the compounds of the invention is the preferred route, being the most convenient and, for example in MED, avoiding the well-known disadvantages associated with intracavernosal (i.c.) administration. A preferred oral dosing regimen in MED for a typical man is from 25 to 100 mg of compound when required. In circumstances where the recipient suffers from a swallowing disorder or from impairment of drug absorption after oral administration, the drug may be administered parenterally, e.g. sublingually or buccally.
For veterinary use, a compound of formula (IA) or (IB), or a veterinarily acceptable salt thereof, or a veterinarily acceptable solvate of either entity, is administered as a suitably acceptable formulation in accordance with normal veterinary practice and the veterinary surgeon will determine the dosing regimen and route of administration which will be most appropriate for a particular animal.
Thus the invention provides a pharmaceutical composition comprising a compound of formula (IA) or (IB), or a pharmaceutically acceptable salt thereof, or a pharmaceutically acceptable solvate of either entity, together with a pharmaceutically acceptable diluent or carrier.
It further provides a veterinary formulation comprising a compound of formula (IA) or (IB), or a veterinarily acceptable salt thereof, or a veterinarily acceptable solvate of either entity, together with a veterinarily acceptable diluent or carrier.
The invention also provides a compound of formula (IA) or (IB), or a pharmaceutically acceptable salt thereof, or a pharmaceutically acceptable solvate of either entity, or a pharmaceutical composition containing any of the foregoing, for use as a human medicament.
In addition, it provides a compound of formula (IA) or (IB), or a veterinarily acceptable salt thereof, or a veterinarily acceptable solvate of either entity, or a veterinary formulation containing any of the foregoing, for use as an animal medicament.
In yet another aspect, the invention provides the use of a compound of formula (IA) or (IB), or a pharmaceutically acceptable salt thereof, or a pharmaceutically acceptable solvate of either entity, for the manufacture of a human medicament for the curative or prophylactic treatment of a medical condition for which a cGMP PDE5 inhibitor is indicated.
It also provides the use of a compound of formula (IA) or (IB), or a veterinarily acceptable salt thereof, or a veterinarily acceptable solvate of either entity, for the manufacture of an animal medicament for the curative or prophylactic treatment of a medical condition for which a cGMP PDE5 inhibitor is indicated.
Moreover, the invention provides the use of a compound of formula (IA) or (IB), or a pharmaceutically acceptable salt thereof, or a pharmaceutically acceptable solvate containing either entity, for the manufacture of a human medicament for the curative or prophylactic treatment of male erectile dysfunction, female sexual dysfunction, premature labour, dysmenorrhoea, benign prostatic hyperplasia (BPH), bladder outlet obstruction, incontinence, stable, unstable and variant (Prinzmetal) angina, hypertension, pulmonary hypertension, congestive heart failure, atherosclerosis, stroke, peripheral vascular disease, conditions of reduced blood vessel patency, chronic asthma, bronchitis, allergic asthma, allergic rhinitis, glaucoma or diseases characterised by disorders of gut motility.
It also provides the use of a compound of formula (IA) or (IB), or a veterinarily acceptable salt thereof, or a veterinarily acceptable solvate containing either entity, for the manufacture of an animal medicament for the curative or prophylactic treatment of male erectile dysfunction, female sexual dysfunction, premature labour, dysmenorrhoea, benign prostatic hyperplasia (BPH), bladder outlet obstruction, incontinence, stable, unstable and variant (Prinzmetal) angina, hypertension, pulmonary hypertension, congestive heart failure, atherosclerosis, stroke, peripheral vascular disease, conditions of reduced blood vessel patency, chronic asthma, bronchitis, allergic asthma, allergic rhinitis, glaucoma or diseases characterised by disorders of gut motility.
Additionally, the invention provides a method of treating or preventing a medical condition for which a cGMP PDE5 inhibitor is indicated, in a mammal (including a human being), which comprises administering to said mammal a therapeutically effective amount of a compound of formula (IA) or (IB), or a pharmaceutically or veterinarily acceptable salt thereof, or a pharmaceutically or veterinarily acceptable solvate of either entity, or a pharmaceutical composition or veterinary formulation containing any of the foregoing.
Still further, the invention provides a method of treating or preventing male erectile dysfunction, female sexual dysfunction, premature labour, dysmenorrhoea, benign prostatic hyperplasia (BPH), bladder outlet obstruction, incontinence, stable, unstable and variant (Prinzmetal) angina, hypertension, pulmonary hypertension, congestive heart failure, atherosclerosis, stroke, peripheral vascular disease, conditions of reduced blood vessel patency, chronic asthma, bronchitis, allergic asthma, allergic rhinitis, glaucoma or diseases characterised by disorders of gut motility in a mammal (including a human being), which comprises administering to said mammal a therapeutically effective amount of a compound of formula (IA) or (IB), or a pharmaceutically or veterinarily acceptable salt thereof, or a pharmaceutically or veterinarily acceptable solvate of either entity, or a pharmaceutical composition or veterinary formulation containing any of the foregoing.
The invention also includes any novel intermediates described herein, for example those of formulae (IIA), (IIB), (IVA), (IVB), (IXA) and (IXB).
The syntheses of the compounds of the invention and of the intermediates for use therein are illustrated by the following Examples and Preparations.
1H Nuclear magnetic resonance (NMR) spectra were recorded using either a Varian Unity 300 or a Varian Inova 400 spectrometer and were in all cases consistent with the proposed structures. Characteristic chemical shifts (xcex4) are given in parts-per-million downfield from tetramethylsilane using conventional abbreviations for designation of major peaks: e.g. s, singlet; d, doublet; t, triplet; q, quartet; m, multiplet; b, broad.
Mass spectra (m/z) were recorded using a Fisons Instruments Trio mass spectrometer in the thermospray ionisation mode.
Room temperature means 20 to 25xc2x0 C.

Pyrazolopyrimidinones which inhibit type 5 cyclic guanosine 3xe2x80x2,5xe2x80x2xe2x80x94monophosphate phosphodiesterase (cGMP PDE5) for the treatment of sexual dysfunction


A roller bearing, particularly for mounting the wheel of a commercial vehicle, has two angular-contact ball bearings placed in an O-arrangement relative to one another. The roller bearing is designed such that each angular-contact ball bearing is associated to a roller body row having a common inner ring with the angular contact ball bearing, wherein the two roller body rows are facing one another and form inner bearing rows.

The invention relates to a roller bearing, in particular for mounting a commercial vehicle wheel.
To mount the wheels of heavy commercial vehicles, use is made, for example, of tapered-roller bearings which, while having a relatively small installation space, have a high load capacity and are thereby particularly suitable for the intended application.
Here, wheel bearing designs are known in which the tapered-roller bearings are designed as individual bearings, which however require a relatively large installation space. To reduce the spatial requirement, tapered-roller bearings have recently been combined to form so-called "compact wheel bearing units" in which the inner rings of the tapered-roller bearings bear against one another at an end side. In passenger vehicle wheel bearings, use is made of compact wheel bearing units of the type in which two angular-contact ball bearings are provided in an O-shaped arrangement, but these angular-contact ball bearings have a lower load capacity than tapered-roller bearings and are therefore less suitable for use in heavy commercial vehicles.
Also worth mentioning in this connection are so-called tandem angular-contact ball bearings in which, in contrast to the O-shaped arrangement, the axial support of force takes place in the same direction, with the balls of one of the two ball rows having a larger diameter and often being arranged at a larger running circle diameter than the balls of the other ball row.
The higher load capacity of the tapered-roller bearings comes at the cost of higher friction losses in relation to angular-contact ball bearings, which leads to correspondingly higher fuel consumption. This may amount to as much as 1% for example in a commercial vehicle with ten wheels.
Furthermore, the unfavorable friction values lead to relatively intense heating of the roller bearing, as a result of which, with the simultaneous introduction of heat from friction heat generated during braking, the service life of the roller bearing is reduced.
In this respect, the known roller bearings constitute only unsatisfactory solutions.
The object on which the invention is based is that of further developing a roller bearing of the above-mentioned type such that its load capacity and service life are optimized while requiring only the smallest possible installation space.
This and other objects are achieved by a roller bearing in particular for mounting a commercial vehicle wheel, having two angular-contact ball bearings in an O-shaped arrangement with respect to one another. Each angular-contact ball bearing is assigned a rolling body row which has a common inner ring with the angular-contact ball bearing, with the two rolling body rows being situated so as to face toward one another and forming the inner bearing rows.
A roller bearing according to the invention combines the high load capacity of a tapered-roller bearing with the service life of a ball bearing, while at the same time having a minimized structural height. This results in significant advantages for use in heavy commercial vehicles, in particular with regard to economical use.
As a result of the lower friction values of the angular-contact ball bearings in relation to a tapered-roller bearing, the need for repairs, such as would otherwise arise as a result of overheating, is greatly reduced, which naturally results in a reduction in operating costs. Furthermore, the installation space which need be made available in a wheel hub can be kept relatively small, with a consequential weight saving, such as is constantly sought in automotive engineering.
According to one advantageous refinement of the invention, the rolling bodies which form the inner bearing rows are smaller in terms of their rolling radius than the balls of the associated angular-contact ball bearings, wherein the rolling bodies of the inner bearing rows may likewise be formed as balls, or else as barrel-shaped or cylindrical rollers.
If balls are used as rolling bodies for the inner bearing rows, the inner bearing rows are formed in the manner of angular-contact ball bearings which are preferably provided in a tandem arrangement with the associated outer angular-contact ball bearing. In this respect, the new roller bearing forms, so to speak, a double tandem angular-contact ball bearing overall.
According to the invention, each outer angular-contact ball bearing and the associated inner bearing row has a common inner ring, such that the rolling bearing is provided, overall, with two inner rings.
In principle, the roller bearing may have a common outer ring for all four bearing rows. It is however also contemplated for each individual rolling body pair composed of an inner and an outer bearing row to be provided with one outer ring depending on installation space and assembly requirements.
As mentioned, the rolling radii of the inner rolling bodies are preferably smaller than the rolling radii of the outer rolling bodies. In addition to this, however, the running circle diameter of the inner bearing rows may be smaller than that of the outer angular-contact ball bearings. It is however also contemplated for the inner and outer bearing rows to be arranged on an equal running circle diameter.
In accordance with the different usage conditions, the two bearing rows of each bearing pair may be positioned at different support angles. To obtain a maximum supporting width, in each case the outer balls of the angular-contact ball bearings are arranged at a large support angle, and the two inner bearing rows are arranged with smaller support angles in order to obtain a maximum radial load capacity. To optimize the radial load capacity, the inner bearing rows may also be formed as purely radial bearings. In this case, to minimize an axial spatial requirement, use should be made of rolling bodies in the form of the stated barrel-shaped or cylindrical rollers.
If cylindrical rollers are used, tolerances arising from an axial bracing of the overall roller bearing must be directly compensated, since then, to a defined extent, only the outer ball rows of the angular-contact ball bearings, which are inclined in relation to one another, absorb the axial load, or determine the axial play during adjustment with regard to the least possible play.
An accurately fitting arrangement may be obtained by way of the inner rings bearing against one another at the end side or by way of correspondingly dimensioned spacer sleeves. Here, the connection of the two inner rings takes place by means of an inner ring joint seal such as is known per se.
Further advantageous embodiments are described herein.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.

Roller bearing, particularly for mounting the wheel of a commercial vehicle

Knorr-Bremse Systems fuer Nutzfahrzeuge GmbH


Electrosurgical apparatuses having bent tip applicators are provided. In one implementation, an electrosurgical apparatus includes an insulating outer tube having a longitudinal axis, a proximal end, and a distal end. An outer tube distal housing has its proximal end coupled to the distal end of the insulating outer tube. A distal end of the outer tube distal housing extends from the insulating outer tube at an acute angle relative to the longitudinal axis. The exemplary electrosurgical apparatus further includes an electrically conducting tube disposed within the insulating outer tube and moveable along the longitudinal axis of the insulating outer tube. An electrode is coupled to a distal end of the electrically conducting tube. The exemplary electrosurgical apparatus may include a knob coupled to the insulating outer tube to effect rotation of the outer tube distal housing in 360 degrees of rotation.

Field
The present disclosure relates generally to electrosurgery and electrosurgical systems and apparatuses, and more particularly, to an electrosurgical apparatus with a retractable blade for use in cold plasma applications, electrosurgical cutting and mechanical cutting.
Description of the Related Art
High frequency electrical energy has been widely used in surgery and is commonly referred to as electrosurgical energy. Tissue is cut and bodily fluids are coagulated using electrosurgical energy.
Electrosurgical instruments generally comprise "monopolar" devices or "bipolar" devices. Monopolar devices comprise an active electrode on the electrosurgical instrument with a return electrode attached to the patient. In monopolar electrosurgery, the electrosurgical energy flows through the active electrode on the instrument through the patient's body to the return electrode. Such monopolar devices are effective in surgical procedures where cutting and coagulation of tissue are required and where stray electrical currents do not pose a substantial risk to the patient.
Bipolar devices comprise an active electrode and a return electrode on the surgical instrument. In a bipolar electrosurgical device, electrosurgical energy flows through the active electrode to the tissue of a patient through a short distance through the tissue to the return electrode. The electrosurgical effects are substantially localized to a small area of tissue that is disposed between the two electrodes on the surgical instrument. Bipolar electrosurgical devices have been found to be useful with surgical procedures where stray electrical currents may pose a hazard to the patient or where other procedural concerns require close proximity of the active and return electrodes. Surgical operations involving bipolar electrosurgery often require methods and procedures that differ substantially from the methods and procedures involving monopolar electrosurgery.
Gas plasma is an ionized gas capable of conducting electrical energy. Plasmas are used in surgical devices to conduct electrosurgical energy to a patient. The plasma conducts the energy by providing a pathway of relatively low electrical resistance. The electrosurgical energy will follow through the plasma to cut, coagulate, desiccate, or fulgurate blood or tissue of the patient. There is no physical contact required between an electrode and the tissue treated.
Electrosurgical systems that do not incorporate a source of regulated gas can ionize the ambient air between the active electrode and the patient. The plasma that is thereby created will conduct the electrosurgical energy to the patient, although the plasma arc will typically appear more spatially dispersed compared with systems that have a regulated flow of ionizable gas.
Atmospheric pressure discharge cold plasma applicators have found use in a variety of applications including surface sterilization, hemostasis, and ablation of tumors. Often, a simple surgical knife is used to excise the tissue in question, followed by the use of a cold plasma applicator for cauterization, sterilization, and hemostasis. Cold plasma beam applicators have been developed for both open and endoscopic procedures. In the latter case, it is often desirable to be able to redirect the position of the cold plasma beam tip to a specific operative site. The external incision and pathway for the endoscopic tool may be chosen to avoid major blood vessels and non-target organs, and may not coincide with an optimum alignment for the target internal tissue site. A means of redirecting the cold plasma beam is essential in these situations.
Elaborate mechanisms have been developed to change the direction of the plasma beam by the surgeon as needed. However, these mechanisms are mechanically complicated, expensive to produce and, in some cases, unwieldy to operate effectively. The small diameter of the endoscopic trocar through which this surgical tool must be inserted places even more severe restrictions on these issues.

Cold plasma electrosurgical apparatus with bent tip applicator


Gas turbine driven oil lifting device for increasing the quantity of oil obtained over a specified time (e.g. barrels per day) and the percentage of total amount obtained from oil-bearing geological deposits. The device is installed in a technical column (1) and consists of sections (12) and (18), separated by a bypass packer (11), on which a gas turbine (9) is fixed by a coupling (14) and a tubing (17) with a plurality of valves (four preferred: (3), (4), (6), and (8)) that are fixed to the gas turbine (9) by a coupling (15). Above the gas turbine (9) is a check valve (16) that is installed within the tubing (17). Parallel with the tubing (17) is a supply tube (2) of the gas turbine that is fixed by at least one coupling. The bottom end of the supply tube (2) is connected to an opening (20) at an upper head (34) of the gas turbine (9) by a flexible hose (7). The device may operate continually and periodically. The device may be applied for recovery of liquids from all liquid-bearing geological deposits having insufficient pressure for natural flow.

Processes for increasing production in "the unit of time" (that is at a particular given time or over a specified time, e.g. barrels per day) and percentage of oil quantity obtained from oil-bearing deposits, used so far, may be divided into chemical, biological and mechanical processes. Chemical processes include the injection of various chemical agents in oil-bearing deposits and to decrease oil viscosity and facilitate it to flow into a bore hole or bore holes. Biological processes include the injection of microorganisms in oil-bearing deposits, where the replication and metabolism products thereof increase the oil deposit pressure and decrease the viscosity of oil. Mechanical processes include processes for the enlargement of the drainage zone, and for increasing the oil deposit pressure and devices for pumping the oil from bore holes. Processes for the enlargement of the drainage zone include hydraulic fracturing processes and making of horizontal bores. Processes for increasing deposit pressure are gas drive and water drive recovery. Devices used for recovery of oil from bore holes having pressure insufficient for natural flow are: bore hole pumps, bore hole centrifugal pumps, screw suction pumps, diaphragm suction pumps, and gas-driven lifting devices. Such gas-driven lifting devices may be of a permanent type, a periodical type, a type of piston lift, and a chamber lift and device for recovery of oil fluid from deep wells, such as disclosed in Croatian patent HR P920143.
A disadvantage of the fore-mentioned solutions, which include a device for recovery of oil fluid from deep wells, is that any of those solutions, used individually, does not increase production dynamics or percentage of oil quantity obtained from the oil-bearing deposits or maintain control over the production process. Additional disadvantages from the known device for recovery of oil fluid from deep wells are that installation is complex and the operation is continuous. Moreover, the quantity of oil obtained over a specified time is comparatively small and restricted by dynamic pressure, which is generated by such an operating regime without damaging the oil bearing deposit.
The aim of the solution according to this application is to construct such a device that will increase production over a specified time and increase the percentage of oil quantity obtained from the oil-bearing deposit, all while using very little energy and maintaining control over production.