摘要 |
1399274 Reciprocating conveyers J H BREMS 18 July 1972 [19 July 1971] 33511/72 Heading B8A Workpieces A are pushed from station to station along a slideway by pushers 26 pivotally mounted at spaced intervals along a pair of bars 2 at respective positions corresponding to the spacing of stations. The bars 2 are reciprocable by a two-way hydraulic jack 10 (Fig. 5). Mounted on the bars 2 are a pair of bars 14, which are reciprocable relative to the bars 2 by the action of an hydraulic jack 24. A control system is associated with each pusher 26, and comprises a sensor 38 forming a bell crank, pivotally mounted at 42 to the plates 2. The other arm 41 of the bell crank is pivotally connected by a link 46 to a coupler arm 34 pivotally mounted at 36 to an actuator arm 32 of the pusher 26. The gravity loading of this control system is such that if free to do so, the actuator 30 will fall, rotating about pivot 36 so as to raise the sensor 38. At the commencement of a conveying cycle, the coupler 34 at any given station, engages (by its tail portion 37a) a stop 54 carried by the plates 14 (there is one stop 54 respective to each station along the length of the plates 14). Operation.-First the jack 24 is operated so as to project the plates 14 in the direction of conveyance. By removal forwards of the stop 54 the coupler arm 34 is allowed to fall and so project the sensor 38 upwardly. If the sensor 38 engages an article A present at the respective station, a recess 37 in the coupler arm 34 is held up clear from engagement with a second stop 52 carrier by the plates 14. If however, no workpiece is sensed, the sensor 38 continues rising, the coupler arm 34 drops further, and the stop 52 is received in the recess 37. Acting on the pivot 36 via the arm 34 the movment of the plates 14 thus causes deflection of the actuator arm 32. All the arms 32 are connected by a chain 56, the upstream end of which is anchored to the machine frame. Thus when any one pusher 26 is raised into working position, all the pushers upstream of the pusher under consideration are extended to working position. The chain forms a catenary between the station under consideration, and the next station but one in the downstream direction of conveyance. The next operational step is the energization of the jack 10 so as to project the plates 2 in the direction of conveyance. This constitutes the feed stroke for the projected ones of the pushers 38. The plates 14 are then retracted relative to the plates 2. Finally the cycle is completed by retraction of the plates 2. Hydraulic and electrical circuits (Figs. 18 and 19, not shown) for operating the jacks 10 and 24 in the correct sequence, are described. |