A brake operating mechanism engages on an overrun brake present on a trailer, such as a caravan. The brake mechanism includes an actuator operated by pressurized air supplied by a buffer store via a valve controlled by a control unit. Downstream of the brake valve is a valve which is open in the non-operative state and closed during operation. A throttle opening is also provided, the drain capacity of which is greater than the pump capacity of an air pump located upstream of the brake valve and connected to the buffer store. As a result, the actuator moves back under all circumstances, i.e., braking action does not take place, and overheating is effectively prevented.
Description
The invention will be described below with reference to an exemplary embodiment illustrated in the drawing, in which:
FIG. 1 diagrammatically shows a side view of a caravan provided with the brake operating mechanism according to the invention;
FIG. 2 shows a detail II from FIG. 1; and
FIG. 3 diagrammatically shows the brake operating mechanism according to the present invention.
Claims
1. Brake operating mechanism for operating a brake, comprising an actuator having two parts, which can be displaced relative to one another, wherein a first part is provided with first attachment means for attachment to a trailer and the second part is provided with attachment means for attachment to a control mechanism of a brake, a power supply for said actuator, a control unit for controlling the power supply to the actuator, and a brake sensor for detecting a braking movement, said brake sensor being connected to said control unit, said power supply comprising a pressurized fluid, a buffer store and a pump being present for said fluid, said actuator being fluid-operated and embodied such that it assumes a non-operative position when there is no fluid pressure, a fluid duct extending between said actuator and said buffer store in which a valve is present which is controlled by said control unit, a throttle opening being provided in said duct downstream of said valve, said throttle opening having a greater drain capacity than the pump capacity of said pump.
2. Brake operating mechanism according to claim 1, wherein said fluid comprises air.
3. Brake operating mechanism according to claim 1, wherein said control valve is closed in the non-driven state.
4. Brake operating mechanism according to claim 1, wherein an additional valve is provided in said duct, downstream of said control valve, which additional valve is open in the non-controlled state and which is closed when said actuator is operated.
5. Brake operating mechanism according to claim 1, wherein said attachment means for attachment to an operating mechanism for a brake comprise a ring.
6. Brake operating mechanism according to claim 1, wherein said brake sensor comprises a G sensor.
7. Brake operating mechanism according to claim 1, wherein said brake sensor comprises a displacement sensor.
8. Trailer comprising a pole having two parts, which can be displaced relative to one another, between said parts an operating mechanism for an overrun brake extends, wherein said operating mechanism comprises an elongate part, which can be displaced relative to the chassis of said trailer as well as a brake operating mechanism for operating a brake, comprising an actuator having two parts, which can be displaced relative to one another, wherein a first part is provided with first attachment means for attachment to a trailer and the second part is provided with attachment means for attachment to a control mechanism of a brake, a power supply for said actuator, a control unit for controlling the power supply to the actuator, and a brake sensor for detecting a braking movement, said brake sensor being connected to said control unit, said power supply comprising a pressurized fluid, a buffer store and a pump being present for said fluid, said actuator being fluid-operated and embodied such that it assumes a non-operative position when there is no fluid pressure, a fluid duct extending between said actuator and said buffer store in which a valve is present which is controlled by said control unit, a throttle opening being provided in said duct downstream of said valve, said throttle opening having a greater drain capacity than the pump capacity of said pump, wherein said attachment means of said second part engage on said elongate part.