LOCK FOR TRAILER EMERGENCY AIR BRAKE SUPPLY LINE COUPLER

Abstract

The trailer emergency air brake supply line coupler is movable between a control position, where air pressure in the supply line causes the trailer emergency air brakes to release so the trailer can be moved, and a park position where the trailer emergency air brake system is vented to automatically engage the trailer emergency air brakes. The lock includes a metal frame attached to the trailer proximate the trailer coupler. First and second spaced side walls extend from the rear wall of the frame on opposite sides of the trailer coupler. A retractable pin extends between the side walls and intersects the path of movement of the supply line coupler preventing movement of the supply line coupler between its control position and its park position. A lock cylinder, padlock or other mechanism retains the pin on the frame.

Claims

1. A lock for the emergency air brake supply line coupler of a trailer emergency air brake system including a trailer coupler fixed to the trailer and configured to connect the air supply line to the trailer emergency air brakes, wherein the supply line coupler is movable between a control position, where air pressure in the supply line causes the trailer emergency air brakes to release so the trailer can be moved, and a park position wherein the trailer emergency air brake system is vented to automatically lock the trailer emergency air brakes, the lock comprising a metal frame having a rear wall attached to the trailer proximate the trailer coupler, first and second spaced side walls extending from said rear wall on opposite sides of the trailer coupler, and a retractable pin extending between said side walls and intersecting the path of movement of the line coupler preventing movement of the line coupler between its control position and its park position.

2. The lock of claim 1 further comprising a lock cylinder, padlock or other mechanism engaging said pin to prevent said pin from being retracted from said frame.

3. The lock of claim 1 wherein said rear wall comprises an opening through which the coupler extends.

4. The lock of claim 3 wherein said rear wall comprises first and second spaced members at least partially defining said rear wall opening.

5. The lock of claim 1 wherein one of said side walls has a surface with an opening and wherein said pin comprises an end larger than said side wall opening.

6. The lock of claim 1 wherein said pin has an end comprising a recess.

7. A lock for the air supply line coupler of a trailer air brake system including a trailer coupler fixed to the trailer and configured to connect the air supply line to the trailer air brakes, wherein the supply line coupler is movable between a control position, where air pressure in the supply line causes the trailer air brakes to release so the trailer can be moved, and a park position wherein the trailer air brake system is vented to automatically lock the trailer air brakes, the lock comprising a metal frame having a rear wall attached to the trailer proximate the trailer coupler, first and second spaced side walls extending from said rear wall on opposite sides of the trailer coupler, and a retractable pin extending between said side walls and intersecting the path of movement of the line coupler preventing movement of the line coupler between its control position and its park position.

8. The lock of claim 1 further comprising a lock cylinder, padlock or other mechanism engaging said pin to prevent said pin from being retracted from said frame.

9. A trailer comprising a trailer emergency air brake system including a trailer coupler fixed to the trailer, an emergency air brake, an emergency air brake supply line, an emergency air brake supply line coupler, said line coupler configured to connect said emergency air brake supply line to said trailer emergency air brake, wherein said emergency air brake supply line coupler is movable between a control position, where air pressure in said emergency air brake supply line causes said trailer emergency air brakes to release so the trailer can be moved, and a park position wherein said trailer emergency air brake system is vented to automatically lock said trailer emergency air brakes, a lock comprising a metal frame having a rear wall attached to the trailer proximate the trailer coupler, first and second spaced side walls extending from said rear wall on opposite sides of said trailer coupler, and a retractable pin extending between said side walls and intersecting the path of movement of said line coupler preventing movement of said emergency air brake line coupler between its control position and its park position.

10. The lock of claim 9 further comprising a lock cylinder, padlock or other mechanism engaging said pin to prevent said pin from being retracted from said frame.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF DRAWINGS

[0020] To these and to such other objects that may hereinafter appear, the present invention relates to a lock for a trailer emergency air brake supply line as described in detail in the following specification and recited in the annexed claims, taken together with the accompanying drawings in which

[0021] FIG. 1 is a partial view of the front of a trailer showing the pneumatic and electrical connections with the lock of the present invention installed on the trailer emergency air brake supply line coupler.

[0022] FIG. 2 shows the trailer emergency air brake line coupler, the trailer service air brake line coupler and how an air brake supply line coupler connects to a trailer air brake line coupler.

[0023] FIG. 3 is an isometric view of the lock of the present invention showing trailer emergency air supple coupler in the control position and the pin received in and secured to the frame;

[0024] FIG. 4 is an isometric view of the lock of the present invention showing trailer emergency air brake supply line coupler in the park position, the pin in the retracted position before it is secured to the frame and the pin received in and secured to the frame.

[0025] FIG. 5 is a perspective view if the lock frame with the pin in place showing the front, bottom and left side;

[0026] FIG. 6 is a perspective view if the lock frame with the pin in place showing the rear, top and left side;

[0027] FIG. 7 is a perspective view if the lock frame with the pin in place showing the rear, top and right side;

[0028] FIG. 8 is a perspective view if the lock frame with the pin in place showing the front, bottom and right side; and

[0029] FIG. 9 is a perspective view of a second preferred embodiment of the frame and pin wherein a padlock is used to secure a pin is modified to receive the padlock lock shackle.

DETAILED DESCRIPTION OF THE INVENTION

[0030] FIG. 1 shows the front of a trailer, generally designated A, with connections to the tractor (not shown). The connections include an emergency air brake supply line, generally designated B, a service air brake system supply line, generally designated C, and an electrical cable, generally designated D.

[0031] The emergency air brake supply line B provides air pressure to control the emergency air brakes for trailer A. When high air pressure is present in supply line B, the trailer emergency air brakes are released, and the trailer can be moved. In the absence of air pressure in supply line B (the line is vented), the trailer emergency air brakes automatically engage, and the trailer cannot be moved.

[0032] The service air brake supply line C provides air pressure to control the service air brakes of trailer A. When high air pressure is present in supply line C, the trailer service air brakes are released, and the trailer can be moved. In the absence of air pressure in the supply line C (the line is vented), the trailer service air brakes automatically engage, and the trailer cannot be moved.

[0033] The electric cable D supplies electric power to operate the lights, signals and ABS brakes of the trailer.

[0034] The emergency air brake supply line B is connected to the trailer emergency air brake system by mating couplers. Each coupler has a metal connecting part and a handle part. The emergency air brake supply line coupler has a handle part 10 which is connected to supply line B and a metal connecting part 12 configured to engage the metal engaging part 14 of the emergency air brake system coupler 16 fixed to trailer A.

[0035] The service air brake supply line C is connected to the trailer service air brake system by mating couplers. Each coupler has a metal connecting part and a handle part. The service air brake supply line coupler has a handle part 18 which is connected to supply line C and a metal connecting part 20 configured to engage the metal engaging part of the service air brake system coupler fixed to trailer A.

[0036] The connections are color coded so they can be easily distinguished. The emergency air brake supply line coupler handle part 10 is red. The service air brake supply line coupler handle part 18 is blue. The electrical cable is green.

[0037] The end of each supply line is externally threaded. Each coupler has an in the internally threaded handle part end configured to receive the supply line end. This allows the supply lines to be disconnected from their respective supply line couplers.

[0038] Each supply line coupler can be moved relative to its respective trailer air brake system coupler between control and park positions. FIG. 3 shows the emergency supply line coupler handle part 10 in the control position, which is, for example, 45 degrees below horizontal. In the control position, the emergency air brakes of the trailer can be engaged or released by the driver as needed by regulating the air pressure in the emergency air brake supply line.

[0039] FIG. 4 shows the emergency supply line coupler handle part 10 in the park position, which is, for example, 45 degrees above horizontal. In the park position, the emergency air brake system of the trailer is vented, and the emergency air brakes of the trailer are engaged such that the trailer cannot be moved. In the park position, emergency air brake supply line coupler metal connecting part 12 can be disconnected from the metal connecting part 14 of the trailer emergency air brakes system coupler.

[0040] Referring now to FIGS. 5-8, the first preferred embodiment of the present invention includes a strong metal frame, generally designated E. Frame E includes a rear wall 22, a left side wall 24 and a right side wall 26. Side walls 24 and 26 extend from opposite edges of rear wall 22. Rear surface 22 includes spaced members 22a and 22b. Frame E is designed to be fixed to the surface of a trailer by fasteners which extend through the openings in the members. Frame E is mounted on the trailer surface surrounding the emergency air brake supply line coupler handle part 1o, as seen in FIG. 1.

[0041] Extending between side walls 24 and 26 is a strong metal pin 28 which, when received on the frame, intersects the path of movement of the emergency air brake supply line coupler handle part 10, such that the emergency air brake supply line coupler handle part cannot be moved between the control position and the park position.

[0042] Pin 28 has an enlarged head 30 on one end which limits how far the pin can be moved through an opening in side wall 26. The other end of pin 18 is received in a lock cylinder 32 which is fixed to side wall 24. The external portion of lock cylinder 32 has an entrance opening 34 for a key which causes the lock cylinder to engage or release the pin end.

[0043] Referring again to FIGS. 3 and 4, those figures show frame E as it would appear mounted on a trailer proximate to and surrounding the emergency air brake supply line coupler with pin 18 situated on the frame. In FIG. 3, the emergency air brake supply line coupler handle part is in the control position beneath pin 18 and cannot be moved from the control position to the park position unless pin 18 is removed, as indicated in FIG. 4.

[0044] With the pin removed, the emergency air brake supply line coupler can be moved to the park position. With the coupler in the park position, the pin can be inserted back into the frame. The pin then prevents the coupler from being moved to the control position. In the park position, the trailer emergency air brake system is vented and cannot be pressurized to release the trailer emergency air brakes. In the park position, the emergency air brake supply line coupler can be disconnected from the trailer.

[0045] Pin 18 has an end 36 of reduced diameter with a circumferential recess. Pin end 36 is configured to be received within and engaged by lock cylinder 32. The lock cylinder prevents the removal of the pin from the frame without a key. Thus, movement of the emergency air brake supply line coupler by unauthorized individuals is avoided.

[0046] FIG. 9 shows a second preferred embodiment of the present invention. In this embodiment the lock cylinder is replaced by a padlock 38 with a shackle 40. In this embodiment, a pin 42 replaced pin 18 and has a loop end configured to be receive the shackle of the padlock.

[0047] It will now be understood that, in the control position, the lock prevents theft of the trailer in stopped traffic because as soon as the supply line is removed by a would-be thief, the trailer emergency air brake system is vented, automatically engaging the trailer emergency air brakes preventing movement of the trailer.

[0048] When parking the trailer, before the tractor is disconnected from the trailer, the driver unlocks and removes pin 18 from frame E and moves the trailer emergency air brake supply line coupler to the park position, venting the trailer emergency air brake system, and causing the trailer air brakes to engage. The pin is then replaced and locked on the frame, preventing the trailer emergency air brake supply line coupler from being moved from the park position to the control position. In the park position, the trailer emergency air brake system cannot be pressurized to release the trailer emergency air brakes. The supply line can then be removed from the line coupler and the trailer can be safely left because the air brakes are engaged, and the trailer cannot be moved.

[0049] While only a limited number of preferred embodiments of the present invention have been disclosed for purposes of illustration, it is obvious that many modifications and variations could be made thereto. It is intended to cover all of those modifications and variations which fall within the scope of the present invention, as defined by the following claims.