Abstract: A fork positioner is mounted on a side-shifting carriage of a forklift truck and has transversely-movable, powered yoke assemblies for detachably engaging the upstanding portions of the forks and selectively moving them transversely toward and away from each other while they are supported by the upwardly-facing surface of the fork-supporting member of the side-shifting carriage. The fork positioner has a frame connected to the outwardly-facing, opposed transverse ends of the carriage fork-supporting member in rearwardly-overlapping relation thereto, so that neither the frame nor the fork-engagement structure of the fork positioner protrudes forwardly beyond the forward extremities of the upstanding portions of the forks, thereby minimizing the forward protrusion of the fork positioner beyond the front axle of a counterbalanced lift truck and thus maximizing its load-carrying capacity.

Abstract: A fork truck is provided with a collision-preventing safety arrangement which initiates an emergency stopping in response to a contact with or detection of an obstacle. That safety arrangement comprises a safety device which at least adjacent to a load carrier (3) encloses the space for accommodating a picked-up load (20) on a level within the height range of a human being. That safety device is designed to permit a handling of the load (20) by means of the load carrier (3) at least in a forward direction. For that purpose the safety device may comprise a confining structure, which in its operative position encloses at least the space adjacent to the load carrier (3) and is movable out of its operative position when a load (20) is to be handled.

Abstract: In apparatus for transporting semiconductor wafers, a spatula contains a single major recess for receiving a wafer. Adjacent one edge of the recess is a shoulder for locating the wafer in the sequence of operations for loading the spatula. As a result of the sequence, the center of the wafer is held at a predetermined, known location.

Abstract: The manipulator for sheet-metal pieces is used in conjunction with a sheet-metal working machine and has two rotatable holding members (20) displaceable in three dimensions. The holding members (20) each have both clamping tongs (22), which act on the surface of the sheet-metal piece (24) to be worked, and a clamping strip (23) exerting pressure parallel to the sheet surface. It thereby becomes possible for the sheet-metal piece to be worked, in a first working phase when it is still plane, to be grasped along two parallel edges by means of tongs and, after the first working, to be held only by means of the clamping strips.

Abstract: A storage assembly or facility comprises a shelving block having compartments, a lifting jack and a tie bar. The lifting jack is operatively connected to the tie bar for vertically shifting the tie bar in front of a vertical array of storage compartments. The tie bar is provided with a plurality of telescoping receiver members for inserting into the compartments and subsequently removing therefrom items to be stored. For storing goods of different sizes, the compartments have a modular length equal to the common width of a plurality of columns of the compartment array.

Abstract: An extension device for a forklift truck, the truck having extending and movable truck forks, the extension device having a frame with channels therein for receiving the truck forks and one or more extension forks connected to the frame above the channels, with one or more securing arms pivotably connected to the frame for disengagingly contacting the truck.

Abstract: A machine for transporting tote pans to and from storage compartments arranged longitudinally in vertical rows along an aisle includes a vertically movable carriage provided with a pair of longitudinally spaced, transversely extending tote pan supporting guides which are transversely shiftable between centered and tote pan transfer positions. Associated with the guides is a pair of endless chains, each arranged in a horizontal orbit extending below one of the guides around the sides and ends thereof and carrying a pair of equidistantly spaced pins projecting above the support level of the guide, the pins on one chain being aligned longitudinally with the pins on the other chain. The chains are driven simultaneously in opposite directions on a storage or retrieval cycle synchronously with a cam which shifts the support assembly transversely.

Abstract: Apparatus for loading and unloading palletized materials (C) into and from isothermal delivery wagons (F). The apparatus comprises a powered carriage (4) which is longitudinally movable on parallel guides (1,1') secured to the upper interior portion of the wagon (F). A telescopic guiding and lifting/lowering structure connected to the underside of a powered and transversely movable slide (17) and supporting in cantilever fashion a fork (28) for handling the palletized loads (C), comprises at least one jack (26, 26',29) of the multiple-stage single or double-acting type, and preferably of the hydraulic type. The fork (28) is rotated about a vertical axis in order to angularly position it with respect to the load to be handled, and is then locked in such position.

Abstract: Apparatus to allow transporting a load by a vehicle having lifting forks reduced in length to combine with a rectangular pallet having side and end edges. The pallet has transversely extending floor boards and longitudinally extending stringers separated by spacer blocks with a deck of transversely extending boards mounted on the stringers. The assembly provides transverse channels into which the forks can be entered from either side edge to pick up the loaded pallet, and also provides longitudinal channels for receiving the forks entered from either end edge. By reducing the effective length of standard forks, the outer ends of the forks are prevented from projecting from the remote side edge of the pallet when the forks are fully entered into the transverse channels. The length of the pallet plus the arrangement of the floor boards place the outer ends of the lifting forks clear of the outermost floor board when the forks are fully entered into the longitudinal channels.

Abstract: The invention provides conveying apparatus consisting of a framework adapted to stand beside a vehicle and having a floor in substantial alignment with a battery support bed of the vehicle. Longitudinal track devices extend parallel to the floor on the framework and spaced from the floor to receive the battery between the floor and the track devices. A transport mechanism has drive devices coupled to the track devices for operation to move the transport mechanism longitudinally along the track devices and a coupling assembly is attached to the transport mechanism for movement with the transport mechanism and includes an upwardly biased connector adapted to releasably engage the battery so that on operation of the transport mechanism the battery may be loaded onto or unloaded from the floor.

Abstract: A yoke-type stripper for an article stacker in which a series of paddles extending horizontally from vertically moving conveyor chains each carries an article that becomes a member of the stack. The stripper has rear and front rows of laterally spaced apart vertical bars. Carrier bars extending horizontally from vertical bars in the rear row constitute the bottom of the yoke. The paddles have fingers which support the articles and which pass downwardly between the bars to let the bottom article in the stack rest on the top edges of the carrier bars. A shuttle table is located adjacent the yoke and the table has slots into which the yoke bars can shift. The carrier bars are at a higher level than the table top when the stack is accumulating. Fluid work cylinders shift the yoke and the stack therein to the table slots while the carrier bars are kept at said higher level clear of the table so the pads are not dragged.

Abstract: An improved boom-supportable device for lifting large rocks, broken concrete or asphalt pieces, and the like from the ground without particulates. The invention includes a generally upright frame member having a lower edge, a shelf-like member extending laterally from the frame lower edge to a distal end and defining substantial voids, and devices removably attaching the shelf-like member to the frame lower edge selectively in either a forward position or a rearward position. The shelf-like member preferably has a plurality of elongated parallel teeth spaced along the lower edge. The teeth are most preferably separate, each individually attached to the lower edge.

Abstract: A device for emptying flexible or rigid containers having flexible discharge stubs for in bulk goods where the discharge stubs are sealable by being tied shut and always issue into the emptying device from where the in bulk goods are conveyed out by partial vacuum or free fall. The emptying device (6) consists of an upright cylindrical housing (7) having an outside diameter less than the inside diameter of the discharge stub (4). This housing, when connected, is spanned by the discharge stub (4). At least two jaws (10) which when closed are spaced away from the housing wall are provided to which are mounted at least one elastic belt, a cord (11) or the like which in the closed state of the jaws (10) rests while prestressed over the entire periphery of the housing (7) against the discharge stub (4) spanning the housing (7).

Abstract: A shelf service apparatus in the form of a crane for storage of rod-shaped material that is accommodated in self-supporting pallet boxes, it being possible for the pallet boxes to be lifted by supports on their end faces by carrying devices which can be moved vertically and horizontally by a crane bridge that can be moved in the longitudinal direction of the storeroom. Furthermore, at least one load cross-piece is arranged in the crane bridge parallel to the pallet boxes in such a manner that it can be removed by the carrying devices, which load cross-piece is of the same length as the pallet boxes and is provided on its end faces with supports in a manner corresponding to the pallet boxes.

Abstract: An improved catalyst handling process and system is provided to safely, effectively, and automatically transport catalyst by remote control to and from resid hydrotreating units. The process and equipment feature computerized monorail equipment for efficiently transporting special fresh catalyst containers and spent catalyst containers. Various electronic equipment is provided to electronically detect the type of catalyst stored in the catalyst containers. Lift elevators, four-prong liftfork trucks, remote control tilting mechanisms, catalyst transfer lines, deoiler units, bridge cranes, and other transport vehicles, as described, can also be used.

Abstract: A fork for a fork lift truck having a blade and shank connected by a heel, with a top hook on the shank and a bottom hook near the heel, the bottom hook being constructed so as to be locked and unlocked to the carriage of a lift truck to facilitate engagement of the fork with the carrier and reduce manual effort of the operator and obviate special positioning of the fork prior to connection as is commonly required.

Abstract: A push-pull slipsheet handler for a forklift truck is capable of utilizing the truck's standard forks for load-supporting purposes, while enabling mounting and demounting of the push-pull assembly and forks in unison with respect to the lift truck carriage. The upstanding portions of the standard forks are suspended from a transverse mounting member affixed to the frame of the push-pull assembly at an elevated position. The mounting member has a pair of fork-supporting surfaces positioned in transversely offset relation to vertically pivotable push-pull links, thereby minimizing forward protrusion of the push-pull assembly in its fully-retracted position despite the mounting of the standard forks on the push-pull frame. The construction also permits side shifting of the push-pull assembly and standard forks as a unit relative to the lift truck carriage.

Abstract: A pallet sensing system, for a low lift pallet-type fork truck having load wheels extendible downwardly away from and retractable upwardly toward the forks to raise and lower the forks, is characterized by sensors for detecting proper alignment of the fork load wheels with respect to an opening in a bottom deck of a pallet. Upon the forks being extended into the pallet, the sensors disable lift controls of the truck to prevent the wheels from being extended away from the forks to lift the pallet until the sensors detect that the wheels are aligned for unobstructed passage through the bottom deck opening, whereupon the sensors enable the lift controls. The system prevents the pallet bottom deck from being broken by the wheels should an attempt be made to lift the pallet when the wheels are not positioned to pass freely through the opening, but would instead strike and break the bottom deck.

Abstract: A trailer for lifting and transporting a railway car minus its usual wheeled trucks utilizes a pair of independently positioned wheeled frames in the form of front and rear units that can be located at opposite ends of the railway car. Each wheeled frame supports a forklift assembly having transversely spaced protruding arms capable of fitting under the floor of the railway car while straddling the central longitudinal beam extending from its one end to the other. The forklift assemblies are selectively secured to the railway car to form an integral trailer capable of transporting it on a highway within normal height limitations. The front and rear units can be used to maneuver the railway car into place above a foundation, and can raise or lower the railway car as necessary to remove or place it as desired.

Abstract: A driveway for tractor-trailers is elevated along one side having a side coupling runner mounted to roll on wheels in a track along the side of the driveway facing a single-arm rotary loader. The runner is longer than the tractor-trailer and has a lift push gate at one or both ends for lowering in front of the tractor to push the runner along its track and has recesses for vertical coupling rods or tubes on the loader's trailer-lifting turntable to engage in to move the loader with the tractor to rotate the loader into alignment under the trailer and lift for transfer. Then the tractor driver can release the fifth-wheel and lift the gate and drive away. The loader is further rotated or driven and disengaged from the runner before the runner is returned by motor drive. The loader can load the trailer removed from the tractor onto a railway car as in my earlier U.S. Pat. No.

Abstract: In a loading and unloading apparatus, a plurality of guide rails are disposed as directed in the horizontal direction on a front surface of a support plate for a main body of the loading and unloading apparatus, which support plate has a fork at its bottom portion, base portions of a pair of arms which can be arbitrarily opened and closed in the directions of coming close to and separating from each other for clamping and releasing an object, are movably supported by these guide rails, and at the tip end portions of the respective arms are provided hooks which can be arbitrarily moved in the back and forth directions of the arms.

Abstract: A push-pull slipsheet handler mountable on a standard hook-type lift truck carriage compatibly with load-handling forks mounted on the carriage. The slipsheet handler comprises a push-pull assembly and split platen, both of which receive their vertical support from the load-supporting surfaces of the forks. Attachment of the push-pull assembly to the lower hook-type bar of the carriage provides resistance against fore-and-aft movement of the slipsheet handler. To convert the truck rapidly to a fork-type truck capable of handling standard rigid pallets rather than slipsheets, the platen may be quickly removed leaving the push-pull assembly in place or, alternatively, the push-pull assembly and platen may be removed as an integral unit.

Abstract: An improved forklift apparatus can be provided by utilization of a forklift extension kit including an elongated base member that is removably attached to the forks of the forklift vehicle. Auxiliary fork assemblies are releasably attached to the base member and can be subjectively positioned along the base member to lie parallel with the vehicle forks. Locking and safety mechanisms can be mounted on the base member and fork assemblies to prevent any inadvertent displacement of the fork assemblies.

Abstract: A lift truck load handling attachment having a quick-disconnect hook assembly for quick mounting or demounting of the attachment on a lift truck carriage. The hook assembly comprises a hook mounting member fastened to the rearwardly-facing surface of the frame of the load-handling attachment, slideably mounting an upwardly-facing hook for vertical reciprocation of the hook relative to the mounting member. The hook and mounting member respectively have elongate, vertically-oriented interlocking slides for permitting such vertical reciprocation while preventing rearward movement of the hook relative to the mounting member. A locking pin is selectively insertable transversely to limit downward movement of the hook relative to the mounting member, and the vertical slides and pin are located below the engagement surface of the hook when in its engaged position so as to permit direct abutment between the front of the lift truck carriage and rear of the attachment frame.

Abstract: The present invention relates to an automatic storage and retrieval system for extracting individual storage elements from locations in a two dimensional array and replacing each extracted element into any other vacant location in that array or in some other location, possibly a second two dimensional array opposed to the first array and spaced from it by a distance only slightly greater than the length of the element. The present invention specifically relates to a system in which the bins are engaged by the extractor element along their sides.

Abstract: A low load lift adapter designed for use with a forklift truck comprising an upper frame adapted to be secured to the teeth of the forklift and having a vertically disposed frame section extending downwardly from the forward end thereof. A pair of spaced-apart pocket members are secured to the lower end of the vertically disposed frame and are adapted to removably receive a pair of fork teeth therein.

Abstract: A wheel manipulator for engaging and retaining the hub of a wheel thereto, having a base frame with a vertical column, a carriage slidably mounted on the column and adapted to be vertically adjustably positioned thereon, a turret rotatably mounted on the carriage and a retainer for securing the wheel to the turret for manipulation of the wheel on the base frame.

Abstract: An automated handling system intended notably for storehouses in which miscellaneous articles are kept, for allowing either the restocking of the storehouse, or the regrouping of articles picked up in the storehouse for constituting lots or articles which correspond to a customer's order. The system comprises a central control and management computer and one or a plurality of self-powered trucks adapted to handle stock bins and order receiving bins in the storehouse, and to pick up articles from the bins to constitute lots of articles and gather the various customers' orders.

Abstract: This invention is directed to an apparatus for lifting objects. The apparatus is suspended from a cable which is attached to a crane. The apparatus is used in construction such as in the construction of buildings. The apparatus can connect with a precast concrete panel and lift the precast concrete panel to a desired opening in a building under construction. Also, the apparatus can lift building material to a desired opening in a building, to a proper location in a dam under construction, and to a tower under construction such as a high voltage electric line tower, a radio and television tower and the like. The crane can be on top of the article being constructed such as a building or a dam or the crane can be on the ground. The cable is suspended from the crane and attaches to the apparatus so that the position of the apparatus can be varied both horizontally and vertically and also away from the article under construction and toward the article under construction.

Abstract: A wheel chair is provided which is adapted to permit the chair to be separated from the wheeled chassis so that the chair may be positioned on a seat of an automobile. The wheeled chassis provides support for the chair on the side of the chair so that the chair may be brought into the automobile through the open door with the wheeled chassis moving beneath the automobile. The support for the chair is rotatably on the wheeled chassis so that the chair can be rotated into alignment with the seat in the automobile. The support for the chair is also vertically adjustable so that the chair may be lowered to rest on the automobile seat. The wheeled chassis and support for the chair may then be disassembled and stored in the automobile.

Abstract: Provided herein is a forklift attachment which is easily assembled and disassembled from the forklift including a mounting bracket, two independently pivotable, hydraulically actuated arms pivotally connected to the bracket where the arms are positioned to cooperate with the forklift tines, two hydraulic jacks one each associated with and pivotally connected to each arm and pivotally connected to the bracket to rotate themselves and cause rotation of the arms when actuated, and a hydraulic fluid and control system adapted to prevent obstruction of forklift operations and to permit independent actuation of the arms.

Abstract: A no crease system for a push/pull attachment on a lift truck for avoiding damaging loads. A gripper having a bar and a shoe for gripping and releasing a slip sheet carrying a load is provided with a control circuit for closing the gripper to the gripping position when the push plate is extended for protecting the load from damage by an open gripper. The circuit includes a valve connected to the push/pull attachment and actuated by the push/pull attachment when the push plate is fully extended. The valve may be deactuated by a control switch.

Abstract: Horizontally and vertically actuable apparatus for loading/unloading workpieces from a work station. The workpiece holder is contained on a driven workpiece holding tower having in one embodiment a laterally floating bearing coupled to an endless drive assembly whereby up/down motion is imparted relative to a controlled rotary motion in one direction. Horizontal motion is controlled via a driven endless notched belt and associated magnetic transducing and counting apparatus for determining relative horizontal position. Alternative embodiments of a driven pivoting roller arm and a driven lead screw are also disclosed for imparting respective vertical and horizontal motion.

Abstract: For use with a fork lift truck having a pair of vertically spaced apart forks which are raised or lowered in union, apparatus for exchanging a loaded or unloaded pallet with an unloaded or loaded pallet, respectively, by back and forth movement of the fork lift truck and by vertical movement of the forks. The apparatus comprises a pallet supporting member which is biased under the force of a spring so as to move to an extended pallet supporting position from a retracted position out of a path of pallets carried by the forks; a lever which is located at a position higher than said pallet supporting member; and a connecting member which is formed with elongated slots into which are fitted said lever and said pallet supporting member, said connecting member being raised by upward movement of an unloaded pallet engaging the lever to incline it upwardly, the connecting member retracting the pallet supporting member and latching it.

Abstract: An attachment for lift trucks to enable the truck to work in narrow aisles and manipulate loads in front of and to both sides of the truck without turning the truck. A side shifter which includes a pair of parallel moving arms for supporting the load in which the arms are pivotally supported from a track intermediate the ends of the arms. The side shifter retracts within the width of the truck, but extends beyond the sides of the truck for handling loads.

Abstract: A push-pull slipsheet handler mountable on a standard hook-type lift truck carriage compatibly with load-handling forks mounted on the carriage. The slip-sheet handler comprises a push-pull assembly and split platen, both of which receive their vertical support from the load-supporting surfaces of the forks. Attachment of the push-pull assembly to the lower hook-type bar of the carriage provides resistance against fore-and-aft movement of the slipsheet handler. To convert the truck rapidly to a fork-type truck capable of handling standard rigid pallets rather than slipsheets, the platen may be quickly removed leaving the push-pull assembly in place or, alternatively, the push-pull assembly and platen may be removed as an integral unit.

Abstract: A lift truck fork of substantially reduced weight without sacrificing load carrying capacity, the weight reduction being effected by forming at least one of the load or lift arms with a channel-like cross-section extending throughout a substantial portion of the length of such arm, additionally forming the flanges of said channel-like portions with parabola-like edges.

Abstract: Bale handling and hay distributing apparatus comprises a round-bale holder equipped with a device for rotating the bale around its central axis and a hay shredding unit. The bale holder is supported by a lift mechanism having a pair of vertically movable, projecting arms at the end of which the holder is pivotally connected. A device for rotating the bale holder with respect to the supporting lift mechanism is provided, so that the holder can be positioned in a hay dispensing position and in two different bale loading positions respectively rotated of an angle of 90.degree. and 180.degree. with respect to the hay dispensing position. Hooks projecting from the longitudinal sides of the holder are provided having a cooperating jaw-movement for grasping the bale during loading operation.

Abstract: A fork lift vehicle lift fork having provisions to signal a user when wear of the fork on a surface or surfaces which are subject to wear, has progressed to an extent which may result in failure of the fork if subject to further continued use, such provisions including a plate element fastened adjacent a surface in such a way as to cause automatic release of the plate element when the wear has progressed to a predetermined extent, to assure visible notice of that fact, similar provisions being suitable for use in like manner to indicate wear of a separate surface subject to wear.

Abstract: Crate carrying apparatus able to be mounted on a fork lift truck or other lifting device, having at least first and second groups of crate engaging members which can be selectively presented for crate lifting, the engaging members of each group being spaced apart at distances appropriate to the spacing apart of apertures in the crates of a stack of crates of the particular group.

Abstract: An automatic sputtering apparatus for coating semiconductor wafers uses shuttle wafer carriers and elevators to handle wafers within the apparatus. The wafer carrier has a hole in the center. One side of the wafer carrier is opened, thereby forming a throat in the shuttle wafer carrier in the form of the letter C. The elevator has a cantilevered shaft. The upper part of the shaft of the elevator is centered under the wafer while the lowest part of the cantilevered shaft is under a point outside the wafer carrier. The connecting portion of the shaft passes through the throat of the wafer carrier as the wafer is lifted. Since the lifting portion of the shaft is outside the wafer carrier, the shuttle can move with the elevator in the up position. The pedestal for holding the wafer on the elevator is equipped with arms which project upward at an angle to the horizontal, thereby confining the wafer to a pedestal.

Abstract: The invention concerns improvements in universal vertical lift system couplings and attachments therefor; in vertical lift systems, improvements in wide engagement and narrow engagement universal couples and attachments; and improvements in couples of vertical lift systems, both wide gauge and narrow gauge, which permit attachment engagements be fixed directly to the working attachment member, rather than requiring the conventional intermediate universal support or carry.

Abstract: A mechanism for removably securing forks to a forklift truck and the like includes a hook shaped upper end for engaging a support shaft mounted on the forklift truck and a freely pivotal release mechanism attached to the shank of the fork having a first surface closely adjacent to the shaft on which the fork is mounted. The pivoting release mechanism precludes disengagement of the hook from the supporting shaft when the fork is in operating position. Upon pivotal movement of the fork about this supporting shaft the pivotally mounted release mechanism pivots under the effect of gravity to present a second surface adjacent to the supporting shaft thereby permitting disengagement of the fork from the shaft.

Abstract: A gravity operated load stabilizing device is provided for use with forklifts the device comprising an inverted J-shaped member which engages the load by gravity when the fork is raised and is disengaged from the load when the fork rests on a surface.

Abstract: A semiconductor crystal ingot (14) is supportively engaged by an ingot handling apparatus (22) which contacts a base (38) of the ingot (14) with a base support (36) and opposite sides of a lateral surface of the ingot (14) with at least one pair of jaws (37). The jaws (37) are retained adjacent to but out of firm contact with the lateral surface of the ingot until after the support (36) firmly supports the weight of the ingot. The support and the at least one pair of jaws are retracted from a furnace (10) simultaneously in a lateral direction with no relative movement to withdraw the ingot from the furnace.

Abstract: A load handling vehicle of the sidewinder type which can handle loads located on either side of the load handling vehicle without manual help. In particular, the load handling vehicle has at least two load handling conveyors which can be used to handle two loads on one trip of the load handling vehicle.

Abstract: Round bales require to be unrolled in order that the contents are available to the cattle and usually they are unrolled by mounting same in a frame and then towing the frame behind a tractor. The present device is mounted at the front of a tractor and includes a frame with two spaced and parallel prongs for spearing the bale in order to move it in position from a storage area. When in the desired location, the prongs are withdrawn and one of the prongs is engaged axially with the bale. The prong is then lowered until the periphery of the bale engages the ground at which time it is unlatched. The tractor is driven forward and to one side thus moving the bale and prong through approximately 90.degree. so that the axis of the bale is perpendicular to the direction of travel. Driving the tractor forward unrolls the bale raising the frame which is tilted forwardly, causes the prong to swing forwardly and latch automatically.

Abstract: An attachment for a lift truck having a vertically movable carriage includes a frame and a carrier slidably engaged within the frame attachable to the carriage of a lift truck. The carrier has at least one receiving pocket and a gate for substantially closing the receiving pocket. A load-supporting element is removably supported on the carrier. The load-supporting element includes a bracket received in the receiving pocket of the carrier and retained by the gate for maintaining the load-supporting element in operable position on the carrier.

Abstract: A push-pull slipsheet handler mountable on a standard hook-type lift truck carriage compatibly with load-handling forks mounted on the carriage. The slipsheet handler comprises a push-pull assembly and split platen, both of which receive their vertical support from the load-supporting surfaces of the forks. Attachment of the push-pull assembly to the lower hook-type bar of the carriage provides resistance against fore-and-aft movement of the slipsheet handler. To convert the truck rapidly to a fork-type truck capable of handling standard rigid pallets rather than slipsheets, the platen may be quickly removed leaving the push-pull assembly in place or, alternatively, the push-pull assembly and platen may be removed as an integral unit.

Abstract: An earth engaging instrumentality is equipped with wedge-like surfaces for displacement of earthen material. Rollers are rearwardly offset from the leading edge of the instrumentality and have chordal segments projecting outwardly beyond the diverging surfaces of the instrumentality to displace earthen material and hence facilitate penetration of same. An open, roller receiving area of the instrumentality is shown as being of a non-uniform width to receive upper and lower rollers of different widths which rollers may be of different peripheral configuration.