AU2012101963A4 - A Docking System - Google Patents

Abstract

A docking system for use with trucks and trailers incorporating a park brake in a pneumatic circuit, the 5 system comprising a controller adapted to be put in series with the park brake pneumatic circuit, the controller being pneumatically coupled to a first indicator positioned adjacent the front of the exterior of the trailer, a second indicator positioned within the trailer 10 and a switch within a door of the trailer whereby when the park brake is activated in cannot be released until the door is closed and the indictors provide a stop/go indication. 39534431 (GHMatters) P92261.AU C-) o C,, Cd, Ca N C,, o* iL 0, ,~ C, - In -S ( \ 0, '- 'N A A A a A! '2 .s (3 ~ -2 o N 0, S - '9 C -:5; 'C C.-

Description

A Docking System

This invention relates to a docking system and especially a system that improves the safety in the loading and unloading of trailers.

Trucks and trailers either in rigid or an articulated form are used extensively in the delivery of goods. The loading and unloading of trucks can be a dangerous exercise especially where the driver of the truck has difficulty in determining whether the loading or unloading procedure has been completed.

When trucks are docked for loading and unloading procedure it is usual to apply a park brake that locks the wheels of the trailer to prevent accidental movement of the trailer. It is important that the park brake is not released until the loading or unloading process is completed. Furthermore, there is a need for the driver and/or the person loading or unloading the trailer to be aware when there is a likelihood of trailer movement leading to potential danger.

It is these issues that have brought about the present invention.

According to one aspect of the present invention there is provided a docking system for use with trucks and trailers incorporating a park brake in a pneumatic circuit, the system comprising a controller adapted to be put in series with the park brake pneumatic circuit, the controller being pneumatically coupled to a first indicator positioned adjacent the front of the exterior of the trailer, a second indicator positioned within the trailer and a switch within a door of the trailer, whereby when the park brake is activated it cannot be released until the door is closed and the indicators provide a stop/go indication.

Preferably, the controller is coupled to the underside of the trailer. The indicators preferably comprise flags of different colours that can be displaced into the view. The indicators also preferably include an audible alarm.

By placing the docking system in series with the park brake circuit the system could not be activated whilst the vehicle is in motion.

An embodiment of the present invention will now be described by way of example only with reference to the accompanying drawings in which:

Figure 1 is a pneumatic circuit diagram illustrating a docking system coupled to a vehicles parking brake circuit; and

Figure 2 is a schematic pneumatic circuit.

Trucks and trailers with pneumatic braking systems usually incorporate two pneumatic circuits namely a blue circuit (Service Supply) that operates the foot brakes of the truck and trailer and a red circuit (Emergency Supply) that operates the park brake on the trailer. The braking systems are similar, notwithstanding the fact that it could be a rigid truck and trailer or an articulated truck and trailer. The embodiment described hereunder relates to a semi-trailer that has a trailer that is driven by a prime mover about a fifth wheel coupling. The prime mover includes a compressor that is driven by the motor of the truck to provide a source of compressed air to operate the pneumatics of the brakes. The trailer usually incorporates a reservoir of compressed air coupled to the park brake and maintained at pressure, via a check valve function, even when the prime mover is disconnected from the trailer. The park brake of the trailer is applied from the cab of the truck, exhausting the air in the park brake actuator and allowing the spring in the actuator to apply the park brake thereby ensuring that the trailer remains locked notwithstanding loss of air pressure. It is usual to release the park brake from the cab of the truck .

In the preferred embodiment, the trailer defines an enclosure with loading and unloading access through a rear door. However, it is understood that this invention is applicable to other types of trailers including curtain sided trailers where the enclosure is closed off by a displaceable curtain that runs along each side of the trailer .

To load or unload trailers of this kind it is first necessary to open the door of the trailer or release the tensioned curtain to provide access to the interior of the enclosure. In this embodiment, movement of the rear door activates a lever thus providing a visual indicator of the door being opened or closed. It is understood that a similar lever mechanism can be used on either curtain of a curtain sided trailer so the same effect. In many loading and unloading situations a docking station is provided whereby the trailer is backed into a recess defined by a raised concrete structure. The concrete structure provides access to the trailer from either the sides or the rear. Forklifts or hydraulic lifting platforms are often used to load pallets on and off the trailer. With a semi-trailer it is usual to first park the trailer and then disconnect the prime mover. It is most important that when the prime mover is reconnected that the driver does not attempt to drive off until the loading/unloading process has been completed.

Docking stations often include warning lights that provide an indication to the driver of when the docking station is free for use.

In the embodiment illustrated in the accompanying drawings the docking system 10 is coupled in series with the red parking brake circuit 11 of the trailer. The docking system 10 incorporates a pneumatic controller 15 that is pneumatically coupled to a first indicator 20 located on the exterior of the front of the trailer, a second, indicator 25 that is located within the rear of the trailer's enclosure. The controller 15 is also coupled to switches 30 & 31 that are actuated by the lever on the door of the trailer. The system is not interconnected with and has no role to play with the blue braking ( Service Line - foot brake) circuit of the prime mover and trailer.

Figure 1 shows the trailer's wheels W with associated parking brakes B. The pneumatic foot operated brakes of the trailer are not shown. An air reservoir R supports a SR2 valve V that allows air to be transferred to the parking brakes B. Springs (not shown) hold the brakes B in the event of a loss of air pressure. The reservoir R is fed via an emergency air supply line S via the SR2 valve V.

The controller 15 has eight ports T1 thru T9, excluding T6. The controller is coupled in series to the rear and front indicators and audible alarms.

The door switches, 31 & 32, include two valves that are actuated by a striker arm attached to the rear door of the trailer. Switch 30 controls the operation of the visual and audible alarms and switch 31 controls the brake interlock on the trailer. Both switches are connected to the controller to enable these functions.

The main air supply to the controller 15 comes from the reservoir R via port Tl, and the emergency supply line S via ports T2 and T5. The controller 15 is also coupled to a small subsidiary reservoir 40 via port T7. This subsidiary reservoir 40 is in turn fed from the main reservoir R but acts as a security measure to provide an additional small supply of compressed air which is secured in the event of failure of the main reservoir R by a check valve 42. This secure air supply is the guarantee that, in the event of an attempt to pull the trailer away from the dock with the rear door open, the visual and audible alarms will operate

The door switch 30 has two ports 1, 2 coupled to the controller 15 via ports T8 and T4.

The door switches 30 & 31 each have two ports. Switch 30 is coupled to T8 on the controller and switch 31 coupled to T3 & T4.

The front indicator 20 is in series with an audible alarm in the form of a whistle 21. The indicator 20 and whistle 21 are coupled in series with the rear indicator 25 and a whistle 26. The front indicator 20 is controlled by switch 30 and the rear indicator controlled by a combination of switch 30 and a signal via T3 from the controller. The rear indicator 25 will turn red if either the door is closed or the controller 15 senses that the park brake has been released.

As discussed above, when the park brake B is applied mechanical springs hold the brakes on. To release the park brake B a lever in the prime mover has to be pushed which causes pneumatic pressure to push the brakes B open against the springs. The vehicle is then ready to drive away. With the docking system 10 of the subject application the controller 15 does not allow the pneumatics to release the park brake B until it is sure that all doors on the trailer are closed. Thus, if a door is open the controller 15 prevents the pneumatic activation of the brake release. Once the door has been closed a signal is sent by switch 31 to the controller 15 allowing the parking brake to be released. If the door is open, the indicator 20 at the front of the trailer is red, thus warning the driver not to attempt to release the parking brake B. If the door is closed, the indicator 20 is green and the driver is aware that the parking brake can be released. The second indicator 25 on the interior of the rear of the trailer provides the person loading the trailer with a ready indication of whether it is safe to complete the loading/unloading operation. When the operator opens the door, if the indicator 25 is red this is a warning that there is a problem and that the operator should cease the loading/unloading operation. If the indicator 25 is green then the operator is free to load or unload the trailer.

If during the loading and unloading procedure a driver attempts to drive off notwithstanding a red indicator 20 at the front of the trailer audible alarms will be sounded to warn both the driver and the person loading or unloading of potential danger. The alarms emanate from the whistles 21 and 26. The park brake will remain on so the driver cannot drive off but the operator should leave the vicinity of the truck and trailer immediately. If the driver then leaves the cab to close the door of the trailer the park brake will not release until the driver returns to the cab and again applies the park brake, allowing the system to reset within the circuit. The newly applied park brake together with the green signal indicating that the door is closed then allows the driver to release the park brake and drive off.

The first indicator 20 is positioned adjacent the coupling between the prime mover and the trailer so that whilst coupling or decoupling the prime mover from the trailer the driver has a ready view of the indicator 20.

Because the docking system is placed in series with the red parking brake circuit (Emergency Supply) of the truck/trailer the docking system does not operate when the vehicle is in motion. Thus, should a door of the trailer open whilst the vehicle is in motion this event will have no effect on the park brake and the vehicle will continue to operate under the blue braking system (Service Supply -foot brake). Although the integrity of the park brake system is not effected in the event of a door opening whilst the trailer is in motion, indicator 20 will change to red, providing a visual to the driver that the door is open. The docking system comes into play through the red park brake circuit (Emergency Supply) only when the vehicle is stationary. Thus there is no danger of the park brake being applied when the vehicle is in motion.

The docking system described above can be retrofitted to a variety of trailers and operates using the pneumatic system of the truck/trailer. The docking system has no electronic components and operates entirely through the air supply that is provided on trailers of this kind. By providing indicators and audible alarms the likelihood of a truck being moved whilst being loaded or unloaded is considerably reduced and thus the likelihood of accidents during the loading and unloading procedures is far less likely .

In the preferred embodiment each indicator 20 & 25 is a sphere with one half coloured green and one half coloured red. The red sphere of each indicator also has a white bar printed across the face to cater for colour blindness. Pneumatic air pressure causes the sphere to rotate so that either the red or the green side is visible .

Claims (12)

1. CLAIMS :

   1. A docking system for use with trucks and trailers incorporating a park brake in a pneumatic circuit, the system comprising a controller adapted to be put in series with the park brake pneumatic circuit, the controller being pneumatically coupled to a first indicator positioned adjacent the front of the exterior of the trailer, a second indicator positioned within the trailer and a switch within a door of the trailer whereby when the park brake is activated in cannot be released until the door is closed and the indictors provide a stop/go indication .
2. 2. The docking system according to claim 1 wherein the controller is coupled to the underside of the trailer .
3. 3. The docking system according to any one of the preceding claims wherein each indicator includes an audible alarm.
4. 4 . The docking system according to any one of claims 1 to 3 wherein the rear indicator indicates stop when either the door is closed or the controller senses that the park brake has been released.
5. 5. The docking system according to any one of the preceding claims wherein the controller prevents release of the park brake.
6. 6. The docking system according to any one of the preceding claims wherein the front indicator indicates stop when the door is open.
7. 7 . The docking system according to any one of the preceding claims wherein if an operator tries to release the park brake with the front indicator indicates stop both indicators submit an audible alarm.
8. 8. The docking system according to claim 7 wherein if the operator then closes the door to allow release of the brake the operator must first re-apply the brake to re-set the circuit.
9. 9. The docking system according to any one of the preceding claims wherein the park brake is operated by a main air reservoir that forms part of the brake circuit, and wherein a subsidiary air reservoir is coupled in series with the controller.
10. 10. The docking system according to any one of the preceding claims wherein each indicators comprises a flag of different colours that can be displaced into view.
11. 11. The docking system according to claim 10 wherein each indicator comprises a sphere coloured green on one side and red on the other, the sphere being caused to rotate through pneumatic pressure.
12. 12 . The docking system substantially as herein described with reference to and as illustrated in the accompanying drawings .