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Preface
Large horsepower vehicles need to install an emergency rescue device which is installed under front bumper of the vehicle, and it is a kind of a host-promoted mechanism that is called winch. The mechanism of the winch brake is to prevent the occurrence of reverse slipping at working time. Winch reversing is very dangerous when the vehicle is in trouble, and it needs to launch the winch to rescue itself.[1],[2] Sudden winch reversing could make the vehicle in a more dangerous state. Therefore, the reliability of the winch brake is crucial.
Considering the limits of the installation position, the brake is installed inside the roller of winch. This design keeps the brake in a confined space. A lot of heat is produced when the winch works, and the heat accumulates in the drum because the heat dissipation is poor, heat accumulation causes the temperature of drum to rise and then leads the Nylon rope which wraps around the drum to burn out.[3],[4] Finally, it will seriously affect the service life of the winch and threaten the safety of personnel.
The ratchet pawl mechanism is a reliable brake mechanism, but it will produce a lot of vibration and noise during the operation. Consequently, it will increase both the possibility of mechanical failure and the cost of brake's manufacturing. As a result of these disadvantages, the ratchet pawl mechanism is not applied widely. The worm gear mechanism is also a kind of brake mechanism, which runs with less noise.[5] However, it will produce a lot of heat in the process. The brake mechanism needs oil lubrication and requires high sealing performance. It needs accurate manufacture which produces high cost, so the brake mechanism with a worm gear mechanism is not applied widely either. Hydraulic winch has a great brake performance, but it has high standards for the hydraulic pump and hydraulic power source device of our vehicle, so this kind of winch is not widely used.[6]
Related research
As shown in [Figure 1], most of the winches use the design that the brake mechanism is mounted inside the winch roller: the left of the winch is power unit which includes electronic control device and motor; the middle of the winch is executing...