An improved conversion custom hard top or roof for vehicles is aerodynamic and provides greater headroom or interior vertical space for the occupants of the vehicle. The replacement roof comprises three separate levels distinguished by the three riser portions. Two of the riser portions are convex and the third riser portion is concave.

1. Field of the Invention
The present invention relates to a van top height extension device. More particularly, the invention relates to a replacement for a conventional or factory van roof which will enlarge the interior vertical space or the headroom of the van and enhance or retain the integrity of the aerodynamics of the van.
Prior to the present invention, van roof extensions included placing square members upon the vehicle. This created greater air friction which resulted in lower gas mileage and greater wind noise.
2. Description of the Relevant Art
Heretofore, there have been various means for providing aerodynamic vehicle roofs.
U.S. Pat. No. 4,257,643 issued in 1981 discloses an air deflector for the roof of a truck cab.
U.S. Pat. No. 4,098,534 issued in 1978 discloses an air deflector for the front portion of a truck trailer.
U.S. Pat. No. 4,206,715 issued in 1980 discloses a vehicle end cap designed to make a trailer more aerodynamic.
U.S. Des. Pat. No. D251,292 issued in 1979 discloses a top for a van including tiered portions. This design differs from the present invention in that only two tiers are provided and they do not consistently rise from front to back and the sides are beveled, not rounded.
U.S. Des. Pat. No. D297,225 issued in 1988 discloses a two-tier van top with a rear spoiler. This design differs from the present invention in that windows are shown and the spoiler would not allow the van top to be as aerodynamic as the present invention.
U.S. Des. Pat. No. D294,934 issued in 1988 discloses a replacement van top. This design differs from the present invention in that it is not rounded aerodynamically and does not include curved sides.
U.S. Des. Pat. No. D286,394 issued in 1986 discloses a van top having two tiers and beveled sides. This design differs from the present invention in that there are only two tiers and does not include rounded sides.
The present invention provides a replacement vehicle top which is aerodynamic, easily attached and provides greater headroom in the vehicle.

Custom hard top, and methods of constructing and utilizing same


A running tool includes subassemblies which release the running tool from the liner hanger in response to application of alternating tensile and compressive forces after application of left-hand torque. A running tool includes subassemblies which set the liner hanger in response to left-hand torque followed by increased pressure, and in response to increased pressure without prior left-hand torque being applied. A running tool includes threaded connections, without torque transmitted through the running tool being transmitted by the threaded connections. A method of setting a liner hanger includes applying a compressive force to the running tool; then applying left-hand torque to the running tool; and then applying a tensile force to the running tool. A method of releasing a liner hanger includes applying left-hand torque to the running tool; and then releasing the running tool from the liner hanger by applying a tensile force to the running tool.

The present invention relates generally to equipment utilized and operations performed in conjunction with a subterranean well and, in an embodiment described herein, more particularly provides a running tool for an expandable liner hanger and associated methods.
Expandable liner hangers are generally used to secure a liner within a previously set casing or liner string. These types of liner hangers are typically set by expanding the liner hangers radially outward into gripping and sealing contact with the previous casing or liner string. Many such liner hangers are expanded by use of hydraulic pressure to drive an expanding cone or wedge through the liner hanger, but other methods may be used (such as mechanical swaging, explosive expansion, memory metal expansion, swellable material expansion, electromagnetic force-driven expansion, etc.).
The expansion process is typically performed by means of a running tool used to convey the liner hanger and attached liner into a wellbore. The running tool is interconnected between a work string (e.g., a tubular string made up of drill pipe or other segmented or continuous tubular elements) and the liner hanger.
If the liner hanger is expanded using hydraulic pressure, then the running tool is generally used to control the communication of fluid pressure, and flow to and from various portions of the liner hanger expansion mechanism, and between the work string and the liner. The running tool may also be used to control when and how the work string is released from the liner hanger, for example, after expansion of the liner hanger, in emergency situations, or after an unsuccessful setting of the liner hanger.
The running tool is also usually expected to provide for cementing therethrough, in those cases in which the liner is to be cemented in the wellbore. Furthermore, the running tool is preferably capable of transmitting torque from the work string to the liner, for example, to remediate sticking of the liner in the wellbore, enable the liner to be used as a drill string to further drill the wellbore (in which case a drill bit may be connected to an end of the liner), etc.
It will, thus, be appreciated that many functions are performed by an expandable liner hanger running tool. If these functions are to be performed effectively and reliably, then the operation of the running tool should be appropriately tailored to the environment in which it is to be used.
Unfortunately, past running tool designs have fallen short in one or more respects. Some designs, for example, require a ball or other plug to be dropped through the work string at the completion of the cementing operation and prior to expanding the liner hanger. However, at substantial depths and/or in highly deviated wellbores, it may take a very long time for the ball to reach the running tool (during which time the cement is setting), or the ball may not reach the running tool at all.
Other running tool designs use a release mechanism which operates by shearing pins in response to set down weight (compressive force in the work string). If this set down weight is applied prematurely (e.g., if the liner becomes stuck) or not at all (e.g., in a highly deviated wellbore), then the liner hanger may be released prematurely or not at all.
Still other running tool designs use a release mechanism which operates in response to right-hand (clockwise) torque applied to the work string, or are otherwise incapable of transmitting substantial torque from the work string to the liner. These designs do not allow the liner to be used as a drill string, and do not allow right-hand torque to be used in some circumstances to free a stuck liner.
It will, therefore, be appreciated that improvements are needed in the art of expandable liner hanger running tools and associated methods of installing expandable liner hangers. These improvements can include improvements to operational efficiency, convenience of assembly and operation, improved functionality, etc. not discussed above.

Running tool for expandable liner hanger and associated methods