Safety mechanism for vehicle tarpaulin system

Safety mechanism for manipulating a tarpaulin mounted to a tarpaulin moving device for selectively covering and uncovering a vehicle body, comprising a transmitting member for connection to the tarpaulin moving device for causing the moving device to move in response to movement by said transmitting member, a drive sprocket, means connecting said drive sprocket to said transmitting member when said drive sprocket is rotated, said drive sprocket being mounted on a shaft, a crank handle selectively operatively mounted to said shaft for rotating said drive sprocket, a ratchet mounted coaxially with said drive sprocket on said shaft, a forward motion pawl, first resilient means urging said forward motion pawl into engagement with said ratchet to prevent said handle from rotating in a reverse direction when said handle is in its operative condition, a safety pawl, a safety latch connected to said safety pawl for selectively moving said safety pawl to an operative position and to an inactive position, second resilient means urging said safety pawl into engagement with teeth on said drive shaft when said safety pawl is in said operative position to prevent rotation of said drive sprocket, said teeth on said drive shaft being the teeth of said drive sprocket, said latch being a lever rigidly connected to said safety pawl for controlling the movement of said safety pawl, said safety pawl and said shaft and said drive sprocket and said ratchet being mounted in a housing, said latch being mounted outside of said housing, a stop member in said housing, and spring means connected to said safety pawl for selectively urging said safety pawl into engagement with said teeth and into abutment with said stop member.

Safety mechanism for manipulating a tarpaulin mounted to a tarpaulin moving device for selectively covering and uncovering a vehicle body, comprising means urging the tarpaulin to move in a first direction, a transmitting member for connection to the tarpaulin moving device for causing the moving device to move in response to movement by said transmitting member in a second direction which is opposite to said first direction, a drive sprocket, means connecting said drive sprocket to said transmitting member when said drive sprocket is rotated, said drive sprocket being mounted on a shaft, a clutch assembly mounted on said shaft, said clutch assembly including an externally threaded hub mounted on said shaft, said drive sprocket being mounted in a free wheeling manner on said shaft, at least one clutch pad on said shaft juxtaposed said drive sprocket, at least one clutch plate locked to said hub juxtaposed said clutch pad, a nut threaded on said hub for being moved on said hub to cause said pad to engage said drive sprocket and lock said drive sprocket to said shaft, a crank handle selectively operatively mounted to said shaft by means of connection to said nut for rotating said drive sprocket when said clutch assembly is engaged, a forward motion ratchet mounted coaxially with said drive sprocket on said shaft, a forward motion pawl, first resilient means urging said forward motion pawl into engagement with said forward motion ratchet to prevent said shaft and said drive sprocket from rotating in a reverse direction when said handle is in its operative condition whereby rotation of said handle causes said drive sprocket to rotate to move the tarpaulin in said second direction and to prevent the tarpaulin from moving in said first direction when said clutch assembly is engaged, means connecting said drive sprocket to said shaft to permit said drive sprocket to have only two conditions of movement, one of said conditions of movement being in a forward motion under the directional control of said forward motion ratchet when said clutch assembly is engaged and said handle and said shaft are rotated to move the tarpaulin in said second direction for uncovering the vehicle body, the other of said conditions of movement being free wheeling when said clutch assembly is disengaged by a backing off rotation of said handle to permit the tarpaulin to move in said first direction in response to said urging means, and said handle and said shaft remaining stationary during said free wheeling movement of said drive sprocket.

Safety mechanism for manipulating a tarpaulin mounted to a tarpaulin moving device for selectively covering and uncovering a vehicle body, comprising means urging the tarpaulin to move in a first direction, a transmitting member for connection to the tarpaulin moving device for causing the moving device to move in response to movement by said transmitting member in a second direction which is opposite to said first direction, a drive sprocket, means connecting said drive sprocket to said transmitting member when said drive sprocket is rotated, said drive sprocket being mounted on a shaft, a clutch assembly mounted on said shaft, said clutch assembly including an externally threaded hub mounted on said shaft, said drive sprocket being mounted in a free wheeling manner on said hub, at least one clutch pad on said shaft juxtaposed said drive sprocket, at least one clutch plate locked to said hub juxtaposed said clutch pad, a nut threaded on said hub for being moved on said hub to cause said pad to engage said drive sprocket and lock said drive sprocket to said shaft, a crank handle selectively operatively mounted to said shaft by means of connection to said nut for rotating said drive sprocket when said clutch assembly is engaged, a ratchet mounted coaxially with said drive sprocket on said shaft, a forward motion pawl, first resilient means urging said forward motion pawl into engagement with said ratchet to prevent said drive sprocket form rotating in a reverse direction when said handle is in its operative condition whereby rotation of said handle causes said drive ratchet to rotate to move the tarpaulin in said second direction and to prevent the tarpaulin from moving in said first direction when said clutch assembly is engaged, said forward motion pawl comprising teeth extending radially from said hub, a safety pawl, a safety latch connected to said safety pawl for selectively moving said safety pawl to an operative position and to an inactive position, second resilient means urging said safety pawl into engagement with teeth on said drive shaft when said safety pawl is in said operative position to prevent rotation of said drive sprocket, said teeth on said drive shaft being the teeth of said drive sprocket, said latch being a lever rigidly connected to said safety pawl for controlling the movement of said safety pawl, said safety pawl and said shaft and said drive sprocket and said clutch assembly being mounted in a housing, said latch being mounted outside of said housing, a stop member in said housing, and spring means connected to said safety pawl for selectively urging said safety pawl into engagement with said teeth and into abutment with said stop member.