1. A pneumatic door closer which includes a cylinder which has a first end and an opposed second end; a piston which is slidingly engaged with the cylinder and which is biased towards the first end; a valve plug, a valve seat and a biasing member to bias the valve plug into sealing engagement with the valve seat to regulate the flow of air from the cylinder; and an adjustable assembly associated with the valve plug to vary the biasing force exerted on the valve plug thereby varying level of air pressure required inside the chamber before the valve plug is disengaged from the valve seat so that air is allowed to escape from the cylinder.
2. A pneumatic door closer as claimed in claim 1 wherein the piston includes an elongate rod and a piston head mounted coaxially inside the cylinder, one portion of the rod securable to a moveable element or a surround of the moveable element and the cylinder securable to the other of the moveable element or a surround of the moveable element.
3. A pneumatic door closer as claimed in claim 2 wherein opening the moveable element causes the piston to move within the cylinder from a biased condition thereby creating a partial vacuum in the cylinder which draws air in from outside the cylinder.
4. A pneumatic door closer as claimed in claim 3 wherein the biasing member is provided to cause the piston to move back the biased condition when the moveable element is released.
5. A pneumatic door closer as claimed in claim 1 wherein a portion of the adjustable assembly forms an end cap for closing one end of the cylinder.
6. A pneumatic door closer as claimed in claim 1 wherein a biasing spring is used to bias the valve plug towards the valve seat.
7. A pneumatic door closer as claimed in claim 5 wherein the valve body forms an end cap for closing one end of the cylinder, the valve body having a passage which extends therethrough from an inner end of the valve body to an outer end of the valve body.
8. A pneumatic door closer as claimed in claim 7 wherein the passage has a first portion which is flared towards the outer end of the valve body to form the valve seat so that a cross sectional diameter of the valve seat gradually increases from the inner end to the outer end.
9. A pneumatic door closer as claimed in claim 8 wherein the valve plug is generally cone-shaped and is dimensioned so that the valve plug corresponds to the valve seat.
10. A pneumatic door closer as claimed in claim 7 wherein a section of the valve body contains a screw thread formation which is complimentary to and interengageable with a screw thread formation of an adjustment member so that the adjustment member can be screwed onto the valve body.
11. A pneumatic door closer as claimed in claim 10 wherein a compression spring is positioned between the adjustment member and the valve plug so that the valve plug is biased by the compression spring into sealing engagement with the valve seat.
12. A pneumatic door closer as claimed in claim 10 wherein the adjustment member is a rotatable knob located at an outermost end of the adjustable assembly.
13. A pneumatic door closer as claimed in claim 11 wherein the adjustment member is operatively associated with the valve plug and the compression spring to adjust the actuating pressure required to open the valve by disengaging the valve plug from the valve seat.
14. A pneumatic door closer as claimed in claim 13 wherein the adjustment member is rotatably moveable relative to the valve body to adjust the compression of the compression spring.
15. A pneumatic door closer as claimed in claim 13 wherein the compression spring is positioned between the valve plug and the adjustment member so that rotational movement of the adjustment member towards the cylinder causes the level of compression in the compression spring to increase by shortening the effective length of the spring.
16. A pneumatic door closer as claimed in claim 15 wherein movement of the adjustment member away from the cylinder decreases the level of compression in the compression spring by increasing the effective length of the spring.
17. A pneumatic door closer as claimed in claim 1 wherein a portion of greater diameter that the remainder of the cylinder is formed in an inner side wall of the cylinder allowing the air to move past the piston when the piston is at a predetermined position relative to the cylinder.
18. A pneumatic door closer as claimed in claim 17 wherein the portion of greater diameter is located towards but not at a first end of the cylinder, being the end of the cylinder to which the piston is biased.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method for communicating between a vehicle and a remote application server, said method comprising:
receiving at a computer system an application message transmitted from a vehicle;
determining by the computer system whether the application message should be forwarded to a remote application server that provides a remote software application associated with the application message; and
redirecting the application message to a local software application executed by the computer system when the application message should not be forwarded.
2. A method in accordance with claim 1, wherein the local software application stores data included in the application message, said method further comprising, after said redirecting the application message:
establishing an uplink connection with the remote application server; and
synchronizing the stored data with the remote software application provided by the remote application server.
3. A method in accordance with claim 1, further comprising forwarding the application message to the remote application server when it is determined that the application message should be forwarded to the remote application server.
4. A method in accordance with claim 3, wherein receiving an application message comprises receiving an application message transmitted from the vehicle using a first communication standard, and forwarding the application message comprises forwarding the application message using a second communication standard.
5. A method in accordance with claim 3, wherein the application message is a first application message of a plurality of application messages, said method further comprising:
assigning a priority to the first application message; and
forwarding the first application message before forwarding a second application message of the plurality of application messages based at least in part on the priority assigned to the first application message and a priority assigned to the second application message.
6. A method in accordance with claim 1, wherein determining whether the application message should be forwarded to the remote application server comprises determining whether a local software application corresponding to the remote software application is executed by the computer system.
7. A method in accordance with claim 1, wherein determining whether the application message should be forwarded to the remote application server comprises determining whether an uplink connection can be established between the computer system and the remote application server.
8. A gateway device for use in communicating between a vehicle and a remote application server, said device comprising:
a vehicle communications unit configured to receive an application message from a computer system onboard a vehicle, wherein the application message is associated with a destination corresponding to a remote application server that provides a remote software application;
a processor unit coupled to said vehicle communications unit and programmed to:
execute a local software application corresponding to the remote software application;
determine whether the application message should be forwarded to the remote application server; and
redirect the application message to the local software application when the application message should not be forwarded to the remote application server,
wherein the local software application interacts with the computer system in a manner that is indistinguishable from the manner in which the remote software application interacts with the computer system.
9. A gateway device in accordance with claim 8, further comprising a wide area network (WAN) communications unit configured to forward the application message to the remote application server when the application message should be forwarded to the remote application server.
10. A gateway device in accordance with claim 9, wherein the application message is a first application message of a plurality of application messages, and said WAN communications unit is further configured to forward each application message of the plurality of application messages to a remote application server corresponding to the application message when an uplink connection can be established with the corresponding remote application server.
11. A gateway device in accordance with claim 10, wherein said processor unit is further programmed to:
assign a priority to each application message of the plurality of application messages based on a destination associated with the application message; and
forward the application messages assigned a first priority before forwarding the application messages assigned a second priority that is less than the first priority.
12. A gateway device in accordance with claim 8, wherein said vehicle communications unit is configured to receive the application message at least in part by receiving vehicle sensor data.
13. A gateway device in accordance with claim 8, further comprising:
a storage device, wherein the local software application updates data in said storage device in response to the redirected application message; and
a wide area network (WAN) communications unit configured to:
establish an uplink connection with the remote application server after the local software application updates the data; and
transmit the updated data to the remote application server.
14. A gateway device in accordance with claim 8, wherein the local software application is a first local software application that corresponds to a first remote software application, and said processor unit is further programmed to:
execute the first local software application in a first virtual machine;
execute a second local software application corresponding to a second remote software application in a second virtual machine;
determine whether application messages should be forwarded to a second remote application server that provides the second remote software application; and
redirect, to the second local software application, application messages associated with a destination corresponding to the second remote application server when application messages should not be forwarded to the second remote application server.
15. A gateway device in accordance with claim 8, wherein:
the application message is a first application message received from a first computer system onboard a first vehicle;
said vehicle communications unit is further configured to receive a second application message from a second computer system onboard a second vehicle, the second application message associated with the destination corresponding to the remote application server; and
said processor unit is further programmed to redirect the second application message to the local software application when the second application message should not be forwarded to the remote application server.
16. One or more computer readable media having computer-executable components, said components comprising:
a local software application component that when executed by the at least one processor unit causes the at least one processor unit to execute a local software application;
a vehicle communication interface component that when executed by at least one processor unit causes the at least one processor unit to receive an application message transmitted by a computer system onboard a vehicle; and
a routing component that when executed by at least one processor unit causes the at least one processor unit to:
determine whether the application message should be forwarded to a remote application server that provides a remote software application associated with the application message; and
redirect the application message to the local software application when the application message should not be forwarded to the remote application server.
17. One or more computer readable media in accordance with claim 16, wherein the application message is a first application message, the local software application creates a second application message based on the first application message, and said components further comprise a wide area network (WAN) interface component that when executed by at least one processor unit causes the at least one processor unit to forward the second application message to the remote application server.
18. One or more computer readable media in accordance with claim 16, wherein the application message is a first application message that corresponds to a first remote software application, and said routing component causes the at least one processor unit to forward a second application message to a second remote application server that provides a second remote software application associated with the second application message.
19. One or more computer readable media in accordance with claim 18, wherein the second application message is received after the first application message, and said computer-executable components further comprise a traffic shaping component that when executed by at least one processor unit causes the at least one processor unit to:
associate a first priority with the first remote software application;
associate a second priority greater than the first priority with the second remote software application; and
forward the second application message before forwarding the first application message based on the first priority and the second priority.
20. One or more computer readable media in accordance with claim 16, wherein said routing component further causes the at least one processor unit to redirect the application message to the local software application at least in part by:
receiving from the computer system onboard the vehicle a request for a network address corresponding to a name associated with the remote application server; and
in response to receiving the request, transmitting a network address corresponding to the local software application to the computer system.