Endless chain driven rack and pinion displacement device for filter presses

Claim 1

In a filter press defining a length having a plurality of plates arranged along said length of said filter press to be compressed in an operating position from front to rear and to be sequentially separated from said operating position, apparatus for separating and displacing said plates comprising, a rail mounted above and extending along said length of said press, a trolley supported on said rail for movement in a direction reciprocably along said rail; an endless chain operably connected to said trolley for moving said trolley, a reversible motor operably connected to said chain for driving said chain, a sprocket wheel fixed on a shaft journalled in said trolley entrained with said chain, separating means comprising an elongated rack supported in said trolley for movement reciprocably between an upper position and a lower position in a direction perpendicular to said direction of movement of said trolley toward and away from said plates, a pinion mounted on said shaft and meshing with said rack, and spring means for biasing said rack in said upper position away from said plates, said spring means also exerting on said sprocket wheel a frictional force preventing rotation of said sprocket wheel while said chain is moving said trolley, pawl means pivotally depending from said trolley and catch means pivotally depending from said trolley in opposition to said pawl means, said catch means for providing that when said trolley is moved in one direction said trolley is stopped at the front-most of said plates and when said trolley is moved in the opposite direction, said pawl means engages said front-most plate permitting further movement of said trolley to displace said front-most plate, said endless chain being thereby operable to sequentially move said trolley to place said separating means in a position between said front-most and next adjacent of said plates and on arresting said trolley in this position to thereafter cause said rack of said separating means to descend to separate said front-most from said next adjacent plate, ascend from between said front-most and said next adjacent plate and permit said front-most plate to be displaced.