| 摘要 |
<p>A device for reciprocating movement, wherein a pair of drivingly connected gearwheels each has an outwardly extending stud that engages one of a pair of spaced, aligned slots in a transverse member. The transverse member is guided for movement by a pair of laterally spaced jambs that include opposed, respective longitudinally extending slots that receive the outer end portions of the transverse member. One of the gearwheels includes an axially extending concentric track that is circular and includes at least one gap or opening, and an electrical switch in contact with the track for regulating the operation of an electrical circuit that controls the rotation of the gearwheels. One of the gearwheels drives an associated gear at a predetermined gear ratio, the associated gear including a pair of spaced, concentric, axially outwardly extending circular tracks, each of which is contacted by a switch that also is connected in series with the electrical switch associated with the one grearwheel, in order to control the application of rotary power to the device.</p> |
