An electric winch of such an electric winch system is mounted on the outside of an automotive vehicle, such as on a front portion, as an assembly unit including an electric motor and relays for controlling rotation in the normal direction or inthe reverse direction, of an electric motor, and the assembly unit is usually fed with a voltage. This, however, is responsible for formation of a short-circuit in the automotive vehicle, which would lead to occurance of an automotive fire from amotor-car accident, such as results from the collision of automotive vehicles.
To attain the object, there is provided according to the present invention an electric winch system including an electric winch provided on the outside of an automotive vehicle, a DC power source provided in an engine room, a pair of connectorparts consisting of one connector part connected to the DC power source and exposed to the outside of the automotive vehicle, and another connector part adapted to be connected to one connector part, and a control switch connected to the other connectorpart and adapted to control the running of an electric motor of the electric winch by way of the pair of connector parts when the pair of connector parts are joined together. The aforesaid electric winch system is characterized by a power source switchprovided between the DC power source and the electric motor of the electric winch in the automotive vehicle, and a power-source-switch controlling means adapted to turn the power source switch to a closed position only when the pair of connector partsare joined to each other.
By the above-described arrangement of the present invention, normally a voltage can not reach the outside of an automotive vehicle, but is applied to the electric winch provided on the outside of the vehicle body only when the pair of connectorparts are connected to each other for operating the electric winch. In the event that the electric winch is damaged due to the collision of automotive vehicles during the running of the automotive vehicle, there is no risk that the DC power source isshort-circuited, which would lead to an automobile fire, and electric damage is prevented.
Preferably, the power source switch is constituted from contact portions of relays, and the power-source-switch controlling means is a closed circuit which is completed by way of the coils of the relays when the pair of connector parts areconnected to each other. As soon as the pair of connector parts are connected to each other for operating the electric winch, a relay serving as the power source switch closes, thereby allowing a current to flow from the DC power source to the electricwinch.
Preferably, the electric motor of the electric winch is a DC series motor, and the control switch is adapted to control a direction of a field system of the DC series motor, thereby running the DC series motor in the normal direction or in thereverse direction.
Preferably, the electric winch is an assembly unit, which comprises a winch mechanism, an electric motor for operating the winch mechanism, a normal rotation relay and a reverse rotation relay both of which are provided between the power sourceswitch and the electric motor and controlled by the control switch. Preferably, the normal rotation relay and the reverse rotation relay are connected to separate series field coils of the electric motor, respectively, and these series field coils areso arranged as to form fields systems directed opposite to each other.
Preferably, the assembly unit of the electric winch comprises a temperature detecting means for detecting the temperature of the electric motor, and the control switch assembly unit comprises indication means adapted to be connected by way of thepair of connector parts to the temperature detecting means, and a control switch.
When it is desired to operate the electric winch 5, the connector part 45 is plugged into the connector part 18. Since the terminal B and C in the connector part 45 are connected to each other, a current is allowed to flow from the battery 14 byway of the terminal C of the connector part 18 to the coil 38 of the relay, thereby rendering the contact pair 22 connected. In an operator connects the base terminal 58 in the control switch 48 to the normal rotation terminal 59 or the reverse rotationterminal 60, then a current is caused to flow to the coil 39 or 41 of the normal rotation relay 23 or the reverse rotation relay 24, thereby rendering the terminal pair 25 or 26 connected, whereby the electric motor 8 is rotated in the normal directionor in the reverse direction, thereby moving the cable 6 in an unwinding direction or in a winding direction.
According to the present invention, only when the connector parts 18 and 45 are joined to each other for operating the electric winch 5, a voltage is applied to the electric winch mounted on the outside of the vehicle body, but usually notsupplied thereto. Thus, electric damage is prevented, and in the event that the electric winch 5 is broken due to an automotive collision, there is no risk that the battery 14 is short-circuited.