Baler

Abstract

A baler having an improved hydraulically driven toggle mechanism for operating a baler pressing platen, improved bale ejector, and improved baler door latch. The toggle mechanism includes opposed pairs of first and second arms .Iadd.foldably joined together at their ends with their other respective ends joined to a pressing box and a pressing platen. The opposed sets of arms are mutually oriented so that as the platen is moved to a withdrawn position, the first and second arms of one set interfold compactly and without interference across the respective first and second arms of the opposed set .Iaddend. .[.and second arms, each first arm of which is a generally C-shaped bell crank arm. The first arms are connected.]. to provide a pressing mechanism which is compact but nonetheless has a long pressing stroke to facilitate production of a large bale in only a few pressing strokes. The bale ejector comprises a lifting plate having a hook which when engaged by a finger secured to the platen lifts the underside of a bale from the rear of the box as the platen is raised to cant the bale onto its forward edge permitting its easy removal from the baler. The lifting plate hook travels in a slot in the baler rear wall and is disengaged from the platen finger by a stop across the slot to drop the lifting plate to the bottom of the box in position for commencement of pressing of a new bale. And, the door latch comprises a rotatable pin and pivotal catch having arced and arcuate surfaces respectively which roll against each other during opening of the door latch to provide an easy opening door latch even when under heavy pressure from a compressed bale.

What is claimed is: 
     
       1. A baler comprising a pressing box having a rear wall, a pair of side walls, a door hinged to a side wall; a platen mounted for reciprocable movement within the pressing box; and a door latch which includes a rotatably mounted pin and a pivotally mounted catch for engaging the pin, either the pin or the catch being mounted to the baler door and the other being mounted to a side wall of the baler, the side of the catch which faces the pin when the door is closed having an indentation for partially encircling and engaging the pin, the indentation including a concave arcuate surface which faces toward the catch pivot and the pin having an arced surface in its circumference on a radius of the pin axis of rotation, which arced surface faces away from the catch pivot when the catch and pin are in position for engagement, the concave arcuate surface having a radius greater than the arced surface radius and partially encircling and contacting the arced surface when the pin and catch are engaged, and which pin includes a projection for contacting the catch as the pin is rotated in a direction to pivot the catch out of engagement with the pin during opening of the door, as the catch pivots the pin arced surface rolls on the catch arcuate surface to pivot the catch and unlatch the door. 
     
     
       2. A baler according to claim 1 wherein the pin is of circular cross section and wherein the arcuate surface has a length greater than the pin radius to accept more than one-half of the pin in the indentation when the pin and catch are engaged. 
     
     
       3. A baler according to claim 2 wherein the catch further comprises means for limiting pivoting of the catch to between an open position away from the pin slightly further than necessary to disengage the pin and catch and a closed position towards the pin and just past the position at which the pin and catch are engaged. 
     
     
       4. A baler according to claim 3 wherein the catch further comprises catch positioning means which biases the catch towards the closed position. 
     
     
       5. A baler according to claim 4 wherein the catch has a beveled end formed by a surface which is a continuation of the arcuate surface and which angles away from both the side of the catch including the indentation and the catch pivot, which beveled end slidably contacts the pin as the door is being closed to pivot the catch from the closed position towards the open position until the beveled end slides by and the indentation reaches the pin whereupon the catch positioning means returns the catch to a closed position with the arcuate surface partially encircling and contacting the pin. 
     
     
       6. A baler according to claim 5 wherein the pin further comprises pin positioning means which biases the pin in a latching position at which the projection will contact the catch upon slight rotation of the pin in a direction to disengage the pin and catch. 
     
     
       7. A baler according to claim 6 wherein the pin positioning means comprises a spring coupled to the baler and to the pin to exert a torsional force against the pin as the pin is rotated from the latching position. 
     
     
       8. A baler according to claim 7 wherein the catch positioning means comprises a coil spring held between the baler and the catch, the spring acting against the catch during opening and closing of the door latch and the spring returning the catch to a closed position when the door is in either an open or a closed position. 
     
     
       9. A baler according to claim 7 wherein the spring is in relatively low compression when the catch is in the closed position but which becomes increasingly more compressed as the catch pivots during opening and closing of the door. 
     
     
       10. A baler having a pressing box having a bottom, a rear wall, a pair of side walls, a platen, a door hinged to one side wall, and a door latch for latching the door to the other side wall and a bale ejection mechanism which comprises: in the rear wall, a first slot in and extending upwardly from the bottom of the wall and a second slot in vertical alignment with the first slot and extending upwardly from slightly above the top of a completed bale;   bale lifting means including an angle iron having one side which normally lies flat against the baler bottom and which is of a dimension sufficient to provide canting of a bale upon raising the lifting means and the other side of which angle iron normally abuts the baler rear wall; and   releasable bale lifting engagement means including a hook which normally is at the bottom of and extends through the second slot, which hook has an upper surface and an under surface which both slope from the rear wall toward the bottom of the box, the upper surface sloping steeply at an angle of about 60° and the under surface sloping gradually at an angle of about 8°, a bar connected to the hook and extending downwardly to the bottom of the baler in alignment with the first slot, a spacer of a thickness slightly greater than the rear wall disposed in the first slot and connecting the bar and the angle iron, a finger on the platen moveable into position for engagement by the hook when the platen is holding a completed bale in a compressed state, and a stop across the second slot at a heighth at which the hook is to be disengaged from the finger.   
     
     
       11. A baler comprising a pressing box having a rear wall, a pair of side walls, a bottom, and a door hinged to one of the side walls; a door latch including a rotatably mounted pin and a pivotably mounted catch for engaging the pin, either the pin or the catch being mounted to the baler door and the other being mounted to a side wall of the baler, the side of the catch which faces the pin when the door is closed having an indentation for partially encircling and engaging the pin, the indentation including a concave arcuate surface which faces toward the catch pivot and the pin having an arced surface in its circumference on a radius of the pin axis of rotation, which arced surface faces away from the catch pivot when the catch and pin are in position for engagement, the concave arcuate surface having a radius greater than the arced surface radius and partially encircling and contacting the arced surface when the pin and catch are engaged, and which pin includes a projection for contacting the catch as the pin is rotated in a direction to pivot the catch out of engagement with the pin during opening of the door, as the catch pivots the pin arced surface rolls on the catch arcuate surface to pivot the catch and unlatch the door;   a pressing platen for reciprocable movement parallel to the box walls between a withdrawn position near the top of the box and an extended position toward the bottom of the box;   a pressing mechanism comprising front and rear sets of opposed arms, each set of arms having a pair of facing, C-shaped first arms each of which is rotatably connected at one end to a support member near the top of the box and rotatably connected at an opposite end to an end of a second arm the opposite end of which is rotatably connected to the pressing platen, a first cross-member connected between one pair of front and rear first arms and another cross-member connected between the other pair of front and rear first arms, the cross-member being connected equal distances from the ends of the first arms connected to the support members and a hydraulic cylinder and piston having the piston connected to one cross-member and the cylinder connected to the other cross-member; and   a bale ejection mechanism comprising a lifting plate which normally rests flat on the bottom against the rear wall, a spacer connected to the plate and disposed in a first vertical slot in the rear wall, a bar connected to the spacer and extending upwardly to the bottom of a second vertical slot in the rear wall at a height slightly above the top of a completed bale, a hook connected to the bar and extending through the wall and into the baler, the hook having an upper and an under surface both of which slope from the rear wall toward the bottom, the upper surface sloping steeply at an angle of about 60° and the under surface sloping gradually at an angle of about 8°, a finger on the platen and moveable from a neutral position into a position for engagement with the under surface of the hook when the platen is holding a bale in a compressed state, and a stop across the second slot at a heighth at which the finger and hook are to be disengaged.   
     
     
       12. A baler having a .[.pressed.]. .Iadd.pressing .Iaddend.box, a pressing platen and a pressing mechanism comprising a toggle mechanism for reciprocally moving the pressing platen between a withdrawn and an extended position and which includes at least a pair of opposing sets of arms, each set including a generally C-shaped first arm and a second arm, each of which C-shaped first arms comprises a straight middle segment between a pair of straight end segments and is rotatably connected at one end to a side wall of, and near the top of, the pressing box to face each other when the platen is is an extended position, which second arms are rotatably connected at one end to the pressing platen, and the other end of which first and second arms are connected to each other, which first arms are equal length and which second arms are equal length, and all axes of rotation of all first and second arms are parallel to each other but normal to the box axis; and   a hydraulic system which includes a piston and a cylinder, which piston and cylinder are connected between corresponding ends of a pair of opposing arms whereby expansion and contraction of the hydraulic system rotates the toggle mechanism first and second arms from a position approaching normal to the box axis to a position approaching parallel to the box axis to provide a compact pressing mechanism and a large charging area when the platen is in a withdrawn position, thereby facilitating production of a large bale in only a few pressing strokes.   
     
     
       13. A baler according to claim 12 in which the baler pressing box has a bottom and a rear wall and has a bale ejection mechanism including a lifting plate which normally lies flat on the pressing box bottom next to the rear wall, and an engagement means for releasably engaging the lifting plate with the pressing platen during an upward movement of the platen, which engagement means comprises: a hook secured to the lifting plate and extending through a vertical slot in the rear wall at a position above a completed bale, the hook having a beveled upper surface which slopes from the rear wall towards the bottom of the box;   a finger secured to the platen and adapted to be moved into position for engagement by the hook as the platen is raised from a completed bale; and   a stop across the slot at a position at which the hook is to be disengaged from the finger, the platen when the hook and finger are engaged during an upward stroke of the pressing platen drawing the lifting plate upwardly until the beveled edge of the hook slidably contacts the stop to force the hook out of the box and disengage the hook and finger to drop the lifting plate to the bottom of the box.   
     
     
       14. A baler according to claim 13 having a door hinged to one side of the pressing box which is closed and latched to confine and permit compression of refuse in the baler but which is unlatched and opened to permit removal of a completed bale, further comprising a door latch which includes a rotatably mounted pin and a pivotably mounted catch for engaging the pin, either the pin or the catch being mounted to the baler door and the other being mounted to a side wall of the baler, the side of the catch which faces the pin when the door is closed having an indentation for partially encircling and engaging the pin, the indentation including a concave arcuate surface which faces toward the catch pivot and the pin having an arced surface in its circumference on a radius of the pin axis of rotation, which arced surfaced faces away from the catch pivot when the catch and pin are in position for engagement, the concave arcuate surface having a radius greater than the arced surface radius and partially encircling and contacting the arced surface when the pin and catch are engaged, and which pin includes a projection for contacting the catch as the pin is rotated in a direction to pivot the catch out of engagement with the pin during opening of the door, as the catch pivots the pin arced surface rolls on the catch arcuate surface to pivot the catch and unlatch the door. 
     
     
       15. A baler according to claim 12 wherein each segment of each generally C-shaped first arm is connected to the pressing box at one end and the other of said end segments is connected to a said second arm, and said first and other end segments are joined to the middle segment at angles respectively of 25° and 15° and have lengths respectively one-third and one-twelfth the middle segment length. 
     
     
       16. A baler according to claim 12 wherein: each second arm is generally L-shaped and is connected to the platen by a leg on the platen, each second arm comprises a pair of straight segments, a first segment of which has a length less than the length of and is connected to the platen leg, and the L-shaped arms face away from each other when the platen is in an extended position.   
     
     
       17. A baler according to claim 16 wherein each said generally L-shaped arm comprises a pair of straight segments joined at an angle of about 60°. 
     
     
       18. A baler according to claim 16 wherein the toggle mechanism comprises two sets of opposing pairs of arms, one set connected towards the rear and the other connected towards the front of the pressing box and wherein the hydraulic system further comprises a cross-member pivotally connected between front and rear arms on one side of the box and another cross-member connected between front and rear first arms on the other side of box; the piston of said hydraulic system being connected to one and the cylinder of said hydraulic system being connected to the other of the cross members. .Iadd. 19. A baler for baling refuse and the like and having a large charging area into which refuse is received, the baler comprising: a pressing box;   a pressing platen movable axially within the box to compress refuse into a bale;   a toggle mechanism for moving the platen axially of the box in a long stroke between a withdrawn position permitting refuse to be charged to the pressing box and an extended position for compressing refuse in the box into a bale, the toggle mechanism comprising a pair of opposed sets of arms, each set including first and second arms foldably joined at their ends and having their other ends pivotally attached adjacent a side of the box to the box and to the platen, respectively, the other ends of one set of arms attached adjacent one side of the box and the other ends of the opposed set of arms attached adjacent an opposed side of the box, the first and second arms of each set being foldable inwardly of the box and being of sufficient length and mutually positioned so as to cross the respective first and second arms of the other set without interference as the arms are simultaneously and compactly folded inwardly of the box into a position approaching normal to the box axis; and   a hydraulic cylinder and piston connected transversely between opposing arms adjacent their other ends and oriented to provide force in a direction normal to the axis of the pressing box to cause folding and unfolding of the arms between positions approaching normal to the box axis and approaching parallel to the box axis. .Iaddend. .Iadd. 20. A baler for baling refuse and the like and having a large charging area into which refuse is received, the baler comprising:   a. a pressing box having upright front, rear and side walls and a bottom;   b. a pressing platen movable parallel of the upright box walls between an upper, withdrawn position and an extended position toward the bottom of the box;   c. a pressing mechanism comprising spaced front and rear pairs of opposed, foldable sets of arms, each set including first and second arms foldably joined at their ends and having their other ends pivotally attached adjacent a side wall of the box respectively to the box adjacent its top and to the platen; the other ends of one set of arms attached adjacent one side wall and the other ends of the opposed set attached adjacent the opposed side wall, the first and second arms of each set being foldable inwardly of the box and being of sufficient length and mutually positioned so as to cross the respective first and second arms of the opposed set of arms without interference as the sets of arms are simultaneously and compactly folded inwardly of the box into a position approaching normal to the box axis, the parallel, spaced front and rear sets of arms adjacent one side wall of the box being received between the opposed front and rear sets of arms adjacent the other side wall of the box;   d. a pair of confronting cross members respectively joining front and rear first arms at points adjacent but spaced from the pivotal connections of the latter to the box; and   e. a hydraulic cylinder and piston mounted between the cross members to force the same away from and toward each other to respectively extend and withdraw the platen. .Iaddend. .Iadd. 21. A baler for baling refuse and the like and comprising a pressing platen for compressing refuse and a toggle mechanism above the platen for driving the latter up and down; a pressing box having front, rear and side walls and within which the platen moves between an upper, withdrawn position and a lower, refuse-compressing position, the pressing box having a large, lower, refuse charging area and a relatively small, upper area within which the platen and toggle mechanism are received when the platen is in its withdrawn position; the toggle mechanism comprising a pair of opposed, inwardly foldable sets of arms mounted adjacent opposed side walls of the box, each set including first and second arms foldably joined at their ends and having their other ends rotatably joined respectively to the pressing box and platen, the first and second arms of the sets being of sufficient length and positioned with respect to the other arms so as to extend into positions approaching parallel to the vertical box axis when the platen is moved downwardly in a long pressing stroke, and being foldable compactly inwardly across one another without interference into positions approaching normal to the box axis within the upper area of the box as the platen is moved to its upper, withdrawn position; the baler including a hydraulic cylinder and piston mounted between opposing first arms at points spaced from but adjacent the rotatable joints between the first arms and the box for extension and retraction in a transverse direction to respectively unfold the arms in a long pressing stroke and to fold the arms compactly across each other as the platen assumes its withdrawn position. .Iaddend. .Iadd. 22. The baler of claim 21 wherein the first arms of each set of arms is configured to project generally downwardly from its pivotal connection to the box and then generally inwardly at an oblique angle when the platen is in its withdrawn position, the hydraulic cylinder and piston being attached to the first arms at vertices of the oblique angles, whereby the platen easily may be started downwardly from its withdrawn position by extension of the piston from the hydraulic cylinder. .Iaddend. .Iadd. 23. A baler for baling refuse and the like and comprising a pressing box having front, rear, side and bottom walls; a pressing platen movable vertically within the box between an upper, withdrawn position and a lower, refuse-compressing position; a pressing mechanism above the platen and comprising spaced, front and rear pairs of opposed, inwardly foldable sets of arms, each set including first and second arms foldably joined together at their ends and having other ends rotatably secured respectively to the box and platen adjacent a side wall of the box, the first and second arms of each set of arms being of sufficient length and being positioned with respect to the arms of other sets as to fold compactly inwardly across the respective first and second arms of opposed sets of arms with the front and rear sets of arms adjacent one side wall passing between the front and rear sets of arms adjacent the opposed side wall when the platen is moved into its withdrawn position; each first arm extending generally downwardly from its pivotal connection to the box and thence generally inwardly at an oblique angle for folding connection to its associated second arm when the platen is in its withdrawn position; the pressing mechanism including a pair of cross members respectively joining front and rear arms at the vertices of the oblique angles, and a hydraulic cylinder and piston extending transversely between the cross members to force the latter apart and together for lowering and raising the platen. .Iaddend.