BALE EJECT DOOR ASSEMBLY FOR BALING PRESSES

Herein described is a bale eject door assembly designed to promote the safe opening of a bale eject door under pressure. The bale eject door assembly can include an end door engaged to and closing the bale exit end of a baling chamber on a baling press, a hinge, a door cylinder piston assembly and a locking mechanism.

TECHNICAL FIELD

The general technical field covered by the present invention relates to baling presses with bale eject doors, particularly, bale eject doors that lock and are opened to eject a fully formed bale.

BACKGROUND

A baling press can be used to bale many types of materials. The bales are densified by hydraulic or mechanical compression force which is retained by manual or automatic application of bale binding or tying material, such as wire ties, steel bands, or plastic straps. Some baling presses are suitable for baling a variety of materials. Occasionally, one type of material is baled and immediately followed by a bale of a different type of material. Such versatility is particularly useful at a commercial or municipal recycling facility. For baling most materials, the ram, bale eject door, baler ceiling, and/or baler floor, could have a slotted platen attached to insert wire ties, steel bands, or plastic straps to fully encircle the material(s) being baled. Usually materials compressed into a baling chamber (a/k/a densification chamber) require several cycles (charges) of the compression ram or other mechanical device with additional material added to achieve the desired bale density or bale length. In most cases, once the desired minimum bale density is achieved, the compressed material at increased density is restrained by encircling/securing with wire ties, metal bands, or plastic strapping. After securing the bale density with binding material, the compression ram is typically retracted from contact with the newly formed bale. Ordinarily, this retraction reduces the compression force against the bale eject door, so the bale eject door can be safely and easily unlocked and opened. The completed bale can then be ejected by the compression ram from the baling chamber, the bale eject door closed, then relocked, and a new bale can begin to be formed.

During the course of development, the inventors observed for the first time that, for some materials such as those with less memory (e.g., fibers, shredded paper, shredded cardboard, agricultural materials, like cotton gin trash), as the compression ram retracts from a newly formed and bound bale, the portion of the bale nearest the bale eject door does not significantly relax or decompress due, in large part, to the friction between the sides of the baling chamber against the bale. Thus, the bale continues to exert substantial force against the bale eject door making it difficult and unsafe to unlock the bale eject door. This may be true, for example, if the bale eject door has inside attachments or structural components to aid the insertion, manually or automatically, of binding material, such as wire ties, steel bands, or plastic straps or if it is an internal designed door. Such designs can hinder the insertion of binding material. This phenomenon is less prevalent (if not non-existent) for materials with more memory such as, for example, plastic bottles or foam rubber.

For years, slow-release locking mechanisms have been used to relieve the residual force exerted by the bale in these situations. In most cases, the slow-release mechanisms are positioned vertically along one edge of the baling chamber and the bale eject door hinge is generally located vertically along the opposing edge of the baling chamber. Some rectangular shaped doors (i.e., width greater than height in most cases) can be quite heavy and difficult to support with the small area available for a vertical hinge. Moreover, adjustments to the hydraulic rod extensions used to open and close doors become difficult when the bale eject doors are cantilevered a significant distance from the short vertical hinges—a condition that grows worse with hinge wear over time and use. Under or over extension of the cylinder rod produced by faulty adjustment can damage the hydraulic cylinder, damage the welded connection to the cylinder attachment ears, or completely break the connection between the attachment ears and the baling press side wall.

Some bale eject door unlocking or locking mechanisms used to address the normally expected issues described above include those that have a hinge attached vertically to the baling chamber structure and a door lock hinged flange with an “L” shaped structure also known as an “angle iron,” In operation, as the flanged door lock rotates about the vertical hinge, the pressure on the bale eject door is slowly released. Other designs use hinged hook(s) attached to the end of a hydraulic cylinder rod that remain engaged to the bale eject door while the rod is slowly extended and until sufficient reduction in pressure is achieved permitting safe manual removal (by rotating the hinged hooks) of the hinged hooks from the bale eject door. Conventional hydraulic cylinders used to unlock chamber end doors, however, are typically affixed to the side wall of the baling chamber and oriented such that the piston rod extends in a direction substantially parallel to the baling chamber side wall. Moreover, such designs usually have cylinder strokes of 8 inches or more.

Unfortunately, such commonly used door lock designs have been known to either open (or potentially open) prematurely due to, for example, high compression pressures, prolonged compression pressure exposure, a leaking hydraulic component, lengthy cylinder strokes, improper cylinder orientation to the direction of the force applied to end doors and/or undersized cylinders. Some are simply of an unsuitable design for full or semi-automatic opening by a hydraulic cylinder (i.e., the hinged hook(s) design). Moreover, in the case of vertical hinge designs, as the end doors open, binding material is in contact with edges of the metal platen slots within the end door. For some types of binding material, such as plastic strapping, this contact causes damage to the binding material. Bale eject doors of full eject baling presses must be fully opened prior to the complete extrusion of the bale from the baling chamber by the compression ram.

SUMMARY

Herein described is a bale eject door assembly and locking mechanism designed to promote the safe opening of a bale eject door under pressure, to prevent premature (partial or total) door openings, to prevent failure or damage of essential structural components, and prevent damage to strapping and/or binding chutes or materials as the door is opened. Most, if not all, of these problems are at least in part caused by the residual pressure inside the bale eject door as described above which make it difficult and unsafe to unlock and open the bale eject door under these conditions. The present invention addresses these issues. The bale eject door assembly is suitable to use with full or total eject baling presses that may employ a single ram stroke of two or more parallel rams, as well as commonly used partial eject baling presses requiring multiple rams strokes.

In one embodiment, the bale eject door assembly comprises an end door (or bale eject door) engaged to and closing the terminal end of an baling chamber on a baling press. In another embodiment, the bale eject door assembly comprises a hinge. In some embodiments, the hinge can be positioned at the interlace between the top of the end door and the top of the baling chamber (door opening from the bottom raising upward), hi other embodiments, the hinge can be positioned at the interface between the bottom of the end door and the bottom of the baling chamber (door opening from the top lowering downward).

In one embodiment, the bale eject door assembly can include one or more cylinder rod assemblies comprising a cylinder and a piston rod engaged to the end door and baling chamber. The cylinder rod assemblies are designed to lock/unlock the end door (e.g, locking cylinder rod assembly) and open the end door (e.g., door cylinder rod assembly) and when the baling press end door can be easily and safely unlocked after the ram has been retracted from the bale without operator intervention, whether or not the bale nearest the eject door has relaxed or decompressed to reduce the pressure exerted on the end door. Opening may follow achievement of a threshold bale length, bale density or full bale densification and bale binding via plastic strapping, metal strapping, metal wire and the like.

In one embodiment, the one or more cylinder rod assemblies are hydraulically, pneumatically, or electrically powered. In another embodiment, the one or more cylinder rod assemblies are hydraulically powered.

In one embodiment, the one or more cylinder rod assemblies can include at least one door cylinder rod assembly. In some embodiments, the at least one door cylinder rod assembly includes a first cylinder end (end opposite a second cylinder end from which the piston rod extends) is secured to the baling chamber. In another embodiment, the first cylinder end is secured near the upper corner of the baling chamber where the baling chamber's lateral side surface and the top surface converge. In some embodiments, the first cylinder end is secured to the baling chamber by a bracket mounted to an baling chamber outer surface. In one embodiment the bracket is fixed and cannot be moved. In another embodiment, the bracket is adjustable and slidably engaged to the baling chamber, such that the distance between it and the end door can be manipulated. In other embodiments, the first cylinder end is fixedly secured a predetermined distance from the end door and, in some embodiments, the predetermined distance is adjustable.

In some embodiments, the at least one door cylinder rod assembly can include a first piston end (opposite end of the cylinder rod assembly to the first cylinder end) that can be secured to the end door. In one embodiment, the first piston end(s) is secured to one or more end door side supports affixed to or integral to the end door lateral sides. The one or more end door side supports can comprise an upper extended portion extending above the top of the end door, the end door hinge, and the top surface of the baling chamber. The upper extended portion can include a brace positioned at an upper extended portion terminus configured to secure the first piston end thereto. The upper extended portion can extend above the end door hinge a predetermined distance to provide adequate leverage to the one or more cylinder rod assemblies for end door opening/closing via pivot about the end door hinge.

In another embodiment, the bale eject door assembly can include a locking mechanism. In one embodiment, the locking mechanism can comprise at least one locking arm positioned and secured to the lateral side surface of the baling chamber. In one embodiment, the bale eject door assembly includes two locking arms positioned on opposite lateral side surfaces of the baling chamber. In another embodiment, the bale eject door assembly includes four locking arms—two arms attached to one lateral side surface and two arms attached to the opposite lateral side surface of the baling chamber chute. In another embodiment, the at least one locking arm is attached to the lateral side surface at two pivoting attachment points. The two pivoting attachment points can comprise a rear brace (positioned closer to the baling material infeed).

In the embodiment with four locking arms (two positioned on each lateral surface of the baling chamber), the rear brace can include two triangular shaped flanges extending from the lateral side surface of the baling chamber and aligned about a vertical axis. In one embodiment, each flange can include a flange aperture positioned at the vertex of the triangular shaped flange and configured to receive a pin. In another embodiment, each of the four locking arms can comprise a rear aperture and a front aperture also configured to receive pins. The rear aperture of the locking arm aligns with the flange aperture described above. In one embodiment, the upper locking arm (of the two locking arms positioned on one of the lateral side surfaces of the baling chamber) engages the upper surface of the upper flange and the lower locking arm engages the lower surface of the lower flange. In another embodiment, when the rear apertures of the locking arms are aligned with the flange apertures, a first pin can be inserted through both locking arms and flanges. The first pin can further comprise a head portion and a nut to ensure that the locking arms are adequately secured to the flanges.

In the embodiment with four locking arms (two positioned on each lateral side of the baling chamber), the bale eject door assembly can include a front brace which, in one embodiment, is a locking cylinder rod assembly. In some embodiments, a tower support member or cylinder (housing a piston) is affixed to and extends from the lateral surface of the baling chamber substantially perpendicular to the baling chamber lateral surface. In the case of four locking arms, there should be two front braces or locking cylinder rod assemblies—one on each side of the baling chamber. The tower support can include a terminal extension comprising a terminal extension aperture configured to receive a pin. In embodiments comprising a locking cylinder rod assembly, the terminal extension can be an extendable rod or piston. In one embodiment, the front apertures of the locking arms align with the terminal extension aperture. In an embodiment, the upper locking arm engages the upper surface of the terminal extension, rod, or piston, and the lower locking arm engages the lower surface of the terminal extension, rod, or piston. In one embodiment, washers or spacers can be added between the locking arm and terminal extension surfaces. In another embodiment, when the front apertures of the locking arms are aligned with the terminal extension aperture, a second pin can be inserted through both locking arms and terminal extension of the front brace or locking cylinder assembly. The second pin can further comprise a head portion and a nut to ensure that the locking arms are adequately secured to the terminal extension.

In one embodiment, the one or more locking arms can comprise engagement hooks or probes positioned at one end of the arm (i.e., the end closest to the end door when the locking arm is secured to the baling chamber). The end door can comprise slots configured to receive the engagement hooks when the locking arms are in a closed position and the end door closed. In one embodiment, the slots are positioned within the end door side supports at the bottom of the end door on the same horizontal and vertical plane as the engagement hooks. In some embodiments, wear inserts can be attached to an interior hook surface, which is the hook surface that will encounter most of the friction or force from a door under pressure from a fully densified bale. Likewise, wear inserts can be inserted into the slots at the point of contact with the engagement hooks. The one, two, three or more engagement hooks (probes) enter the slots within the end door prior to compaction and the beginning of densification. When said end door is desired to be opened (to eject a densified mass of material or a wire tied or strapped bale of any type of materials), the engagement hooks disengage the slots so the end door can be lifted up (or opened down) with the horizontal sectional end door hinge. The engagement hooks disengage when piston extends outward away from the lateral sides of the baling chamber and engage when piston retracts toward the lateral sides of the baling chamber. In some embodiments, the locking cylinder rod assemblies have a cylinder stroke range between about 1″ to 2″. In some embodiments, the stroke range is about 1.5″.

Additional embodiments include those described in the number paragraphs below:1. A bale eject door assembly for a baling press comprising:an end door comprising a hinge and at least one end door side support comprising a first end proximate said hinge and a second end opposite said first end, wherein said at least one end door side support is positioned on opposite sides of the end door and are substantially perpendicular to said hinge;one or more door cylinder piston assemblies configured to open and close said end door; andone or more locking mechanisms comprising at least one locking cylinder piston assembly, at least one locking arm, at least one rear brace, and at least one slot positioned proximate to said second end of said end door side support;wherein said baling press comprises a baling chamber comprising a central axis extending through the length of said baling chamber, and exterior chamber walls;wherein said at least one locking cylinder assembly is affixed to and protruding from at least one of said chamber walls along an axis substantially perpendicular to said baling chamber central axis.2. The bale eject door assembly of 1 wherein said end door comprises two end door side supports.3. The bale eject door assembly of 1 wherein said at least one locking arm further comprises an engagement hook configured for insertion into said at least one slot.4. The bale eject door assembly of 1 wherein said at least one rear brace comprises one or more triangular shaped flanges affixed to at least one exterior chamber wall of the baling chamber.5. The bale eject door assembly of 1 wherein said locking cylinder piston assembly comprises a cylinder stroke distance between about 1″ and 7.5″.6. The bale eject door assembly of 5 wherein said cylinder stroke distance is between about 1″ to 5″.7. The bale eject door assembly of 6 wherein said cylinder stroke distance is between about 1″ and 2″.8. The bale eject door assembly of 7 wherein said cylinder stroke distance is about 1.5″.9. The bale eject door assembly of 4 wherein said triangular shaped flanges comprise a vertex distal said exterior wall of said baling chamber wherein said vertex comprises an aperture configured to receive a first pin and wherein said locking cylinder piston assembly comprises an aperture configured to receive a second pin.10. The bale eject door assembly of 9 wherein said at least one locking arm comprises a rear aperture configured to receive the first pin and a front aperture configured to receive the second pin.11. The bale eject door assembly of 3 wherein said engagement hook comprises a wear insert.12. The bale eject door assembly of 11 wherein said engagement hook comprises an interior face and wherein said wear insert is affixed to said interior face.13. The bale eject door assembly of 12 wherein said wear insert comprises an angled contact surface configured to reduce the force needed to disengage said engagement hooks from said slots.14. The bale eject door assembly of 13 wherein said wear insert is replaceable.15. The bale eject door assembly of 14 wherein said wear insert comprises a material selected from ultra-high molecular weight polyethylene (UHMWPE), PTFE, Teflon, nylon, acetal, and machinable metal.16. The bale eject door assembly of 1 wherein said baling chamber comprises an upper exterior wall, a left side exterior wall, and a right side exterior wall.17. The bale eject door assembly of 16 wherein said hinge is affixed at a junction between a side edge of the end door and a side rim of said baling chamber and wherein said locking cylinder piston assembly is affixed to said upper exterior wall.18. The bale eject door assembly of 16 wherein said hinge is affixed at a junction between an upper edge of the end door and an upper rim of said baling chamber and wherein said at least one locking cylinder piston assembly is affixed to said left side exterior wall and/or said right side exterior support.19. The bale eject door assembly of 18 comprising a first locking cylinder piston assembly affixed to said left side exterior wall and second locking cylinder piston assembly affixed to said right side exterior wall.20. The bale eject door assembly of claim1wherein said locking cylinder assembly axis and said baling chamber central axis forms an angle between about 90 degrees and about 45 degrees.

DETAILED DESCRIPTION

Where values are described as ranges, it will be understood that such disclosure includes the disclosure of all possible sub-ranges within such ranges, as well as specific numerical values that fall within such ranges irrespective of whether a specific numerical value or specific sub-range is expressly stated.

The terms “a,” “an,” and “the,” as used herein, generally refers to singular and plural references unless the context clearly dictates otherwise.

Referring now toFIGS.1-6, an embodiment of the bale eject door assembly100is generally shown installed and positioned at the bale exit end101of a baling chamber102of a horizontal baling press. The novel bale eject door assembly100improves the safety associated with opening an end door103that is under pressure due to force applied by a densified and bound (or tied) bale, to prevent end doors103from opening prematurely, and to prevent failure or damage of essential structural components, including, for example, end door hinges104and cylinder rod assemblies105including, in some embodiments, at least one door cylinder rod assembly105aand at least one locking cylinder rod assembly105b. Furthermore, the bale eject door assembly improves the force required to remove engagement hooks (described in detail below) which is often necessary in order to open the end door103. The bale eject door assembly is suitable to use with partial eject and/or full/total eject baling presses.FIG.1andFIG.2illustrate a bale eject door assembly with an end door in a closed and open position respectively.

As shown inFIGS.1-2, the bale eject door assembly comprises an end door103, an end door hinge104, and one or more cylinder rod assemblies105. As shown inFIGS.1and2, the end door103(or bale eject door) can be affixed to the bale exit end101of an baling chamber102on a baling press. The bale eject door assembly100comprises an end door hinge104configured to affix the end door103to the bale exit end101of the baling chamber102. As illustrated inFIGS.1-6, the end door hinge104can be positioned at the interface between the top of the end door103and the lop of the baling chamber102. In this embodiment, the end door103opens from the bottom pivoting about the end door hinge104located at the top.

In the embodiment shown inFIGS.1-6, the bale eject door assembly can also include one or more door cylinder rod assemblies (shown generally at105ain the figures) comprising a cylinder107and a piston rod108engaged to the end door103and baling chamber102. The one or more door cylinder rod assemblies105aare designed to open the end door when it is safe and practical to do so following attainment of a threshold bale length, density or full bale densification and preceded by bale binding via plastic strapping, metal strapping, metal wire and the like. The one or more door cylinder rod assemblies105acan be hydraulically or pneumatically powered and can control speed in which the end door opens (e.g., slow down) keeping the door from opening too quickly and dangerously when the engagement hooks disengage (described in greater detail below). The bale eject door assembly101embodiment shown inFIGS.1-6comprises two door cylinder rod assemblies105apositioned on opposite lateral sides of the baling chamber102.

Referring toFIG.5for illustration, the cylinder107of each door cylinder rod assembly105acan comprise a first cylinder end109(end opposite a second cylinder end110from which the piston rod108extends) that is secured to the baling chamber102. In one embodiment, the first cylinder end109is secured near the upper corner111of the baling chamber102where the baling chamber's lateral side surface112and top surface113converge. In some embodiments, the first cylinder end109is secured to the baling chamber102by a bracket114mounted to a baling chamber outer surface. In one embodiment the bracket114is fixed. In another embodiment, the bracket114is adjustable and slidably engaged to the baling chamber102, such that the distance between it and the end door103can be manipulated. In other embodiments, the first cylinder end109is fixedly secured a predetermined distance from the end door and, in some embodiments, the predetermined distance is adjustable. For example, in some embodiments, the predetermined distance is 14 inches (14 inch stroke cylinders—maximum extended piston distance).

With continued reference toFIG.5for illustration, the piston rod108of each door cylinder rod assembly105acan comprise a first piston end115(opposite end of the cylinder rod assembly105to the first cylinder end109) that can be secured to the end door103. In one embodiment, the first piston end115can be secured to one or more end door side supports116affixed to or integral to the end door lateral sides117. The one or more end door side supports116can comprise an upper extended portion118extending above the top of the end door103, the end door hinge104, and the top surface113of the baling chamber. The upper extended portion118can include a brace119positioned at an upper extended portion terminus configured to secure the first piston end thereto. In some embodiments, the upper extended portion118can extend above the end door hinge104a predetermined distance to provide sufficient leverage to the one or more door cylinder rod assemblies105afor end door opening/closing via pivot about the end door hinge and provide sufficient door elevation to permit unobstructed bale ejection (e.g., at least 90 degree rotation from closed to open position).

With continued reference toFIG.5, the bale eject door assembly can include one or more locking mechanisms shown generally at120and121. The embodiment shown inFIGS.1-6contains two locking mechanisms (120and121), one on each side of the baling chamber102, In one embodiment, the locking mechanism (e.g.,120) can comprise at least one locking arm122positioned and secured to the lateral side surface112of the baling chamber102. In another embodiment, the bale eject door assembly can include two locking arms total—one positioned on a first lateral side surface112aand one positioned on a second lateral side surface112bof the baling chamber102, Referring to the embodiment inFIG.5, the bale eject door assembly can include four locking arms total—two arms (122a,122b) positioned to one lateral side surface112aand two arms (122c,122d) affixed to the opposite lateral side surface112bof the baling chamber112b.

With continued reference toFIG.5, the at least one locking arm (e.g.,122a) can be attached to the lateral side surface (e.g.,112a) at two attachment points. The two attachment points can comprise a rear brace123a(positioned closer to the baling material infeed) and a front brace124a(positioned closer to the end door). In the embodiment shown inFIG.5, the front brace124ais a locking cylinder rod assembly (same reference number124a). In the embodiment shown inFIG.5comprising four locking arms (122a-d), there are two rear braces (123ab) and two front braces (124ab)—each rear/front brace set affixed to opposite lateral side surfaces (112a-b) of the baling chamber.

With continued reference toFIG.5, in the embodiment with four locking arms, an exemplary rear brace123acan include two triangular shaped flanges125a-bextending from the lateral side surface112aof the baling chamber and aligned about a vertical axis (A). In one embodiment, each flange can include a flange aperture126a-bpositioned at the vertex127of the triangular shaped flange and configured to receive a pin128. In another embodiment, each of the four locking arms (e.g.,122a) can comprise a rear aperture129and a front aperture130also configured to receive pins128and131, respectively. The rear aperture129of the locking arm aligns with the flange aperture126adescribed above. In one embodiment, the upper locking arm122a(of the two locking arms positioned on one of the lateral side surfaces of the baling chamber) engages the upper surface132of the upper flange125aand the lower locking arm122bengages the lower surface133of the lower flange125b. In another embodiment, when the rear apertures129a-bof the locking arms are aligned with the flange apertures126a-b, a first pin128can be inserted through both locking arms and flanges. The first pin128can further comprise a head portion134and a nut135to ensure that the locking arms are adequately secured to the flanges.

Continuing withFIG.5, in the embodiment with four locking arms, an exemplary front brace or locking cylinder rod assembly (according toFIG.5)124a(only one side of the baling chamber fully visible) can comprise a tower support member or cylinder (e.g., hydraulic cylinder)136affixed to and extending from the lateral side surface112aof the baling chamber102along axis (B) which, in the embodiment shown inFIG.5, is substantially perpendicular to the lateral side surface112aof baling chamber102. In one embodiment, the angle between axis (B) and lateral side surface112a(or, as another reference point, an axis (C) extending through the baling chamber as shown inFIG.1) is 90°. In another embodiment, the angle is slightly less than 90° and, in yet another embodiment, the angle is between 45° and 90°. In the case of four locking arms, there should be two front braces (124a(shown) and124b(not shown))—one on each side of the baling chamber. In some embodiments, the tower support member or cylinder136can include a terminal extension, rod or piston137comprising a terminal extension aperture138configured to receive a pin.

In one embodiment, the front apertures130a-bof the locking arms align with the terminal extension aperture138. In another embodiment, the upper locking arm122aengages an upper surface139of the terminal extension, rod, or piston137, and the lower locking arm122bengages the lower surface140of the terminal extension, rod, or piston137. In one embodiment, washers (e.g.,141a-b) can be added between the locking arm and terminal extension surfaces139and140. In another embodiment, when the front apertures130a-bof the locking arms are aligned with the terminal extension aperture138, a second pin131can be inserted through both locking arms and terminal extension, rod, or piston137of the front brace. The second pin131can further comprise a head portion142and a nut143to ensure that the locking arms are adequately secured to the terminal extension, rod, or piston137. When a locking cylinder rod assembly124ais utilized, terminal extension, rod, or piston137extends along axis (B) as described above. In some embodiments, locking cylinder rod assemblies124ahave a cylinder stroke distance of between 1″ and 7.5″. In another embodiment, the cylinder stroke distance is between about 1″ to 5″ or between about 1″ and 2″. In yet another embodiment, the stroke range is about 1.5″.

It should be noted that though the locking mechanism, including the locking cylinder rod assemblies124aare shown inFIG.5to be positioned on the baling chamber lateral side surface112a, the locking mechanism components can be positioned on top of the baling chamber for end doors that open from the side i.e., hinges vertical and positioned on the side of the door. In such embodiments, door cylinder rod assemblies can be positioned appropriately in relation to the vertical side hinge (e.g., on the lateral side surface112a).

In the embodiment shown inFIGS.4and5, the one or more locking arms (see e.g.,122a-b—only two shown due to figure perspective) can comprise engagement hooks or probes144a-bpositioned at one end of the arms (i.e., the end closest to the end door when the locking arm is secured to the baling chamber). The end door103can comprise slots145a-bconfigured to receive the engagement hooks144a-bwhen the locking arms are in a closed position and the end door closed as shown inFIG.1andFIG.3. In one embodiment, the slots145a-bare positioned within the end door side supports116at the bottom of the end door103on the same horizontal and vertical plane as the engagement hooks so that the hooks are easily inserted into the slots.

In some embodiments, wear inserts146a-bcan be attached to an interior hook surface147a-b, which is the hook surface that will encounter most of the friction or force from a door under pressure from a fully densified bale. Likewise, wear inserts148a-bcan be inserted into the slots at the point of contact with the engagement hooks. The wear inserts can be designed or configured to reduce the amount of force required to disengage the engagement hooks from the slot and substantially reduce costs associated with normal friction induced wear. In some embodiments, wear insert (147and148) positions can be adjusted and/or the wear insert's shape can be altered to manipulate (e.g., reduce) the force needed to retract the locking arms from the slots. In other embodiments, the wear inserts are replaceable, Other methods to reduce the force required to disengage hooks from slots and retract the locking arms include but are not limited to adjusting the angle of the wear insert's profile or face, the angle of hook entry into the slots so that the point of contact is likewise adjusted, as well as changing the type of material used. In one embodiment, wear inserts are made of ultra-high molecular weight polyethylene (UHMWPE) also known as high modulus polyethylene (HMPE), PTFE, Teflon, nylon, acetal, a machinable metal, or the like. In a preferred embodiment, wear inserts are made of UHMWPE. The one, two, three or more engagement hooks (probes) enter the slots within the end door prior to compaction and the beginning of densification. When said end door is desired to be opened (to eject a densified mass of material or a wire tied or strapped bale of any type of materials), the engagement hooks disengage the slots so the end door can be lifted up (or opened down) with the horizontal sectional end door hinge.