CN109551043B

CN109551043B - Demolition shear and demolition shear stab-tip insert and tip fitting

Info

Publication number: CN109551043B
Application number: CN201811181935.9A
Authority: CN
Inventors: 丹尼尔·P·雅各布森; 查德·沃德; 丹尼尔·J·里哈拉; 史蒂文·T·勒托
Original assignee: Genesis Attachments LLC
Current assignee: Genesis Attachments LLC
Priority date: 2013-04-09
Filing date: 2013-04-09
Publication date: 2022-02-01
Anticipated expiration: 2033-04-09
Also published as: CN109199701B; CN109551043A; CN109199701A; CN109568012A; CN208447937U; CN109568012B; CN107397628B; CN107397628A; WO2018045939A1; CN107625583B; CN106361506A; CN107625583A

Abstract

A demolition shear and a piercing tip insert and tip fitting for a demolition shear that reduces tip wear and resists retraction forces applied to the piercing tip insert in the event of an interference condition and a snagging of the piercing tip insert. Removal of the scissors necessitates the provision of the piercing tip insert and the nose piece fitting to reduce nose piece wear and resist retraction forces exerted on the piercing tip insert in the event of interference with the piercing tip insert and obstruction of the piercing tip insert.

Description

Demolition shear and demolition shear stab-tip insert and tip fitting

The application is a divisional application of an invention patent application with the application number of 201380077298.X and the application date of 2013, 4 and 9.4, inventing a name of 'detaching scissors and a name of a thorn tip plug and a name of an end head accessory of the detaching scissors'.

Technical Field

The invention relates to a demolition shear and a puncture tip insert and a tip part accessory thereof.

Background

Removal of the scissors entails the provision of a piercing tip insert and a nose piece fitting to reduce nose piece wear and resist retraction forces applied to the piercing tip insert in the event of interference with the piercing tip insert and obstruction of the piercing tip insert.

Drawings

FIG. 1 is a right side perspective view (from the operator's position) of one embodiment of a demolition shear attachment.

Fig. 2 is a left side perspective view of the demolition shear attachment of fig. 1.

Figures 3A-3C illustrate the action of the upper jaw relative to the lower jaw during a typical work condition cutting operation of the demolition shear attachment of figure 1.

Fig. 4 is an exploded perspective view of the jaw pivot of the demolition shear attachment of fig. 1.

Fig. 5 is an enlarged view of the jaws of the demolition shear attachment of fig. 1.

Fig. 6 is the same as that shown in fig. 5, but with the blade insert and the piercing tip insert removed.

Fig. 7 is an enlarged view of the jaws of the scissors attachment of fig. 2 removed.

Fig. 8 is a perspective view of the lower jaw shown in fig. 1 with the upper jaw removed to better illustrate the blade-side cutting blade insert and the guide blade insert.

Fig. 9 is another perspective view of the lower jaw shown in fig. 1, with the upper jaw removed to better show the guide side guide blade insert and the cross blade insert.

FIG. 10 is the same as FIG. 7, but with the blade insert and the puncturing tip insert removed.

FIG. 11 shows the lower jaw of FIG. 9 with the blade insert removed.

Fig. 12 shows different angle views of an embodiment of a shear blade insert, where fig. 12A is a front perspective view, fig. 12B is a front view, fig. 12C is a side view, and fig. 12D is a rear view.

Fig. 13 shows different angle views of one embodiment of a guide blade insert, where fig. 13A is a front perspective view, fig. 13B is a front view, fig. 13C is a side view, and fig. 13D is a rear view.

Fig. 14 shows different angle views of one embodiment of a cross-blade insert, where fig. 14A is a front perspective view, fig. 14B is a rear perspective view, fig. 14C is a side view, fig. 14D is a front view, and fig. 14E is a rear view.

FIG. 15 illustrates various angular views of one embodiment of a blade side piercing tip half, with FIG. 15A being a front perspective view, FIG. 15B being a rear perspective view, FIG. 15C being a front side view, FIG. 15D being an outside side view, and FIG. 15E being an inside side view.

FIG. 16 illustrates various angle views of one embodiment of a leading side piercing tip half, with FIG. 16A being a front perspective view, FIG. 16B being a rear view, FIG. 16C being a front side view, FIG. 16D being a medial side elevational view, and FIG. 16E being a lateral side elevational view.

FIG. 17 is a perspective view of the upper jaw of the removed scissors attachment of FIG. 1, showing the barbed insert in an exploded view with the tip seat of the upper jaw separated.

FIG. 18 is an enlarged side view of the upper and lower jaws of the demolition shear attachment of FIG. 1, with the upper jaw in a fully open condition.

FIG. 19 is an enlarged side view of the upper and lower jaws of the demolition shear attachment of FIG. 1, with the upper jaw in a partially closed position.

FIG. 20 is an enlarged side view of the upper and lower jaws of the demolition shear attachment of FIG. 1, with the upper jaw about to project into the slot of the lower jaw.

FIG. 21 is an enlarged side view of the upper and lower jaws of the demolition shear attachment of FIG. 1, with the upper jaw fully closed and extending into the slot of the lower jaw.

FIG. 22 is an enlarged side view of the upper and lower jaws showing the forces acting on the puncturing tip in an interfered condition.

FIG. 23 is an enlarged side view of the upper and lower jaws showing the forces acting on the puncturing tip in another interference situation.

FIG. 24 is an enlarged side view of the upper and lower jaws illustrating the forces on the puncture tip due to wear of the parent material of the head of the upper jaw end with the upper end of the puncture tip insert blocked.

Detailed Description

Referring to the drawings, like parts and corresponding parts in the several views are designated by like reference numerals. Shown in fig. 1 and 2 are right and left (from the operator's position) perspective views, respectively, of the scissors assembly 10 removed. The demolition shear attachment 10 has a body 12 with a front end 14 and a rear end 16 of the body 12. The rear end 16 may be mounted on a boom or stick 18 of the excavator (see fig. 3A) by means of, for example, a swivel attachment 19 or other suitable mounting attachment known to those skilled in the art. The front end 14 of the main body 12 is provided with a movable upper jaw 40 and a fixed lower jaw 42 (described in detail below).

Fig. 3A-3C illustrate the demolition scissor assembly 10 mounted on the boom or stick 18 of an excavator in a typical operating position, showing the closing movement of the upper jaw 40 relative to the lower jaw 42 during the shearing of a target 11. The target 11 is an optional structural member such as an i-beam or channel, steel plate, pipe, or other material such as scrap metal, sheet metal, or any other object or material suitable for treatment or processing with demolition shears.

As shown in fig. 1-4, the main body 12 is generally formed by a steel side plate 20, a steel side plate 22, a top plate 24, and a bottom plate 26, which together define a generally enclosed area within which the hydraulic actuators 30 (see fig. 3A-3C) and other hydraulic components of the demolition shear 10 are substantially enclosed. The hydraulic actuator 30 is pivotally secured to the rear interior end of the main body 12 by an actuator pivot pin 32 extending through the

steel side plates

20, 22, an internal angle plate (not shown) and a hydraulic yoke 34. The front end of the hydraulic actuator 30 is pivotally mounted to a movable upper jaw 40 by a cylinder pin 36 extending into a cylinder yoke 38 and a cylinder pin hole 39 (see also fig. 17), wherein the cylinder yoke 38 and the cylinder pin hole 39 are located on the rear lobe of the upper jaw 40. Thus, according to the present embodiment, hydraulic actuator 30 is extended and retracted as shown in FIGS. 3A-3C such that upper jaw 40 is rotatable about a longitudinal axis of jaw pivot assembly 60 (described in more detail below) to effect opening and closing of upper jaw 40 relative to lower jaw 42. Access holes with access panels 25 (see fig. 2) are provided in the top panel to enable installation, maintenance, servicing and repair of the hydraulic actuators and other components of the hydraulic system within the body 12.

As best shown in fig. 4, 8 and 9,

jaw bosses

44, 46 on each side of the front end 14 of the body 12 include hub holes 48, 50, respectively. Jaw pivot assembly 60 is disposed within hub bores 48, 50 and pivotally supports upper jaw 40 via pivot bore 54 (see fig. 17).

Jaw pivot assembly 60 includes

flanged bushings

56, 58 mounted in hub bores 48, 50. The spindle 62 is press fit within the pivot bore 54 to rotate with the upper jaw 40. The main shaft 62 includes a central bore 64, and a tie rod 66 having a threaded end 68 is disposed in the central bore 64. The end caps 70, 72 are secured to the

flange bushings

56, 58 by threaded fittings that extend into the aligned bores of the

flange bushings

56, 58 and are threadably received in the internally threaded aligned bores in the

bosses

44, 46. The tie rod nut 74 is threaded onto the threaded end 68 of the tie rod 66. Tie rod nuts 74 are secured to the end caps 70, 72 by threaded joints threaded into aligned bores in the threads of the

flange bushings

56, 58. According to the present embodiment, the tie-rods 66 and tie-rod nuts 74 laterally restrain and prevent the

hubs

48, 50 from being affected by lateral forces exerted on the jaws during a shearing operation.

As best shown in fig. 4 and 8, a lateral jaw stabilizing disc assembly 80, such as the invention disclosed in U.S. patent No. 7,216,575, may be used in conjunction with a mating wear plate or wear surface 82 (see fig. 17) provided on an adjacent side of the upper jaw 40 to prevent lateral movement of the upper jaw 40 during a shearing operation until the upper jaw extends into a slot 96 (described in detail below) in the lower jaw 42.

As shown in FIGS. 5-11, the lower jaw 42 includes forwardly extending, laterally spaced and generally parallel jaw beams 90, 92 and a cross beam 94 extending transversely between the laterally spaced jaw beams 90, 92. The laterally spaced jaw beams 90, 92 together with the cross beam 94 form a slot 96, and the upper jaw 40 is placed into the slot 96 during the shearing process (see fig. 3C and 4). As described in more detail below, the forwardly extending jaw beam 90 is used to position the shear blade inserts and guide the blade inserts and is referred to hereinafter as the blade side jaw beam 90. Another forwardly extending jaw beam 92 is used to provide structural rigidity to the lower jaw and laterally restrain and guide the upper jaw from extending into the slot 96 during shearing, which is hereinafter referred to as the guide side jaw beam 92.

As best shown in fig. 10, the inside of the blade side jaw beam 90 includes a shear blade seat 100, the shear blade seat 100 being used to provide a set of hardened steel shear blade inserts 110 (fig. 7 and 8). One embodiment of a shear blade insert 110 is shown in fig. 12. Each shear blade insert 110 has a substantially planar

vertical wear surface

114, 116 and a planar

horizontal wear surface

118, 120. The vertical wear surfaces intersect the planar horizontal wear surface to form four shear edges 122. The cutting blade insert 110 has parallel beveled end faces 124, 126 forming a parallelogram structure such that when the cutting blade insert 110 is positioned and oriented within the cutting blade seat 100, adjacent end faces ride against each other at a downward tip (see fig. 7 and 8). According to the present embodiment, since the cutting blade inserts 110 are all parallelepiped-shaped, the cutting blade inserts 110 can be rotated and oriented relative to each other within the cutting blade holder 100, such that all four cutting edges 122 can be used as cutting edges during use. The planar vertical wear surfaces 114, 116 include counterbores 130 for receiving threaded nipples 132 (preferably socket head cap screws) in the counterbores 130 to removably mount the shear blade insert 110 in the shear blade seat 100. The head of the nipple 132 may be seated in the counter bore 130. The threaded end of the threaded nipple 132 extends through the counterbore 130 and the aligned hole 134 (see fig. 10) in the shear blade seat 100 and is secured by a nut 136 (see fig. 5 and 9) which nut 136 is seated in a counterbore 138 on the outside of the blade side jaw beam 90.

As best shown in fig. 10, the inside of the blade side jaw beam 90 further comprises a guide blade seat 200 for providing a hardened steel guide blade insert 210 (best shown in fig. 8). One embodiment of a guide blade insert 210 is shown in fig. 13. Each guide blade insert 210 has a substantially planar

vertical wear surface

214, 216 and a planar

horizontal wear surface

218, 220. The vertical wear surfaces intersect the planar horizontal wear surfaces to form four shear edges 222. The guide blade insert 210 has parallel beveled end surfaces 224, 226 forming a parallelogram structure. The beveled end faces 224, 226 of the guide blade insert 210 are complementary to the beveled end faces 124, 126 of the shear blade insert 110 so that when the guide blade insert 210 is positioned and oriented within the guide blade housing 200, one of the end faces 224, 226 will bear against one of the end faces 124, 126 of an adjacently disposed shear blade insert 110 (best shown in fig. 8). According to the present embodiment, since the guide blade inserts 210 are each parallelepiped-shaped, the guide blade inserts 210 can be rotated and oriented in the guide blade holder 200 (which may be replaced with a guide side guide blade holder 300 described below), so that all four cutting edges 222 can be used as cutting edges during use. The vertical wear surfaces 214, 216 include internally tapped threaded bores 230, and threaded connectors 232 (e.g., bolts) are placed in the threaded bores 230 to removably mount the guide insert 210 in the guide insert holder 200. The threaded end of the nipple 232 extends through an aligned counterbore 234 (fig. 5 and 9) in the outside of the blade side jaw beam 90 and is threaded into the internally threaded bore 230 of the guide blade insert 210.

As best shown in fig. 9 and 11, the guide side jaw beam 92 further includes a guide blade housing 300 (see fig. 11) for positioning a guide blade insert 210 also used on the blade side guide blade housing 200 such that the guide blade insert 210 can be interchanged between the guide side guide blade housing 300 and the blade side guide blade housing 200. Thus, the guide insert 210 is held fixed to the guide insert seat 300 by the same threaded connector 232 (e.g., a bolt) extending through aligned counterbores 334 (fig. 7, 8 and 10) in the outer side of the guide side beams 92 and threaded into the threaded bore 230 of the guide insert 210 in substantially the same manner as the insert side guide insert seat 200.

As best shown in fig. 9 and 11, the beam 94 includes a cross-blade mount 400 (see fig. 11) for providing a hardened steel cross-blade insert 410 (see fig. 9). Fig. 14 illustrates one embodiment of a cross-blade insert 410. The cross-blade insert 410 has a substantially planar front wear surface 414, substantially planar top and

bottom surfaces

418 and 420, substantially planar end surfaces 424 and 426, and a back surface 428. The back face 428 includes four evenly radially spaced internally threaded bores 430. The rear face 428 also engages a projection 432 for fitting into a recess 435 (see fig. 11) in the cross-blade mount 400. The front vertical wear surface 414 intersects the top wear surface 418, the bottom wear surface 420, and the end surfaces 424 and 426 to form four shear edges 422. Preferably, the chisel insert 410 is positioned at right angles to four radially spaced internally threaded bores 430 so that the chisel insert 410 can be rotated four times at a 90 angle on the chisel seat 400 so that all four cutting edges 422 can be used as cutting edges during use. The cross-blade insert 410 is secured to the cross-blade seat 400 by threaded joints 434 (e.g., bolts) (see fig. 5 and 7) that extend through counterbores in the cross-beam 94. The threaded end of the threaded connector 434 is disposed within the aligned internally threaded bore 430 of the back side 428 of the cross-blade insert 410.

The upper jaw 40 is provided with a blade side and a guide side corresponding to the adjacent blade side jaw beam 90 and guide side jaw beam 92 of the lower jaw 42, respectively. The blade side of the upper jaw 40 includes a cutting blade mount 500 (see fig. 6) for positioning a cutting blade insert 110 (see fig. 5) that is also used on the cutting blade mount 100 of the lower jaw 42 so that the cutting blade insert 110 can be interchanged between the upper and lower jaws, thereby reducing the number of different blades required to be deployed by the cutting attachment 10. However, the shear blade 110 on the upper jaw faces the upper tip of the lower jaw (compare fig. 5 and 7) opposite the lower tip. The shear blade insert 110 is secured to the upper jaw in substantially the same manner as the lower jaw. The threaded end of the threaded nipple 132 extends through the counterbore 130 and the alignment hole 534 of the upper shear insert holder 500 and is secured by a nut 136 disposed in the counterbore 538 (see fig. 7) of the guide surface of the upper jaw 40.

As shown in fig. 6, 10 and 17, the forward-most end or tip 601 of the upper jaw 40 includes a tip seat 600, and the tip seat 600 is used to provide a hardened steel piercing tip insert 610 (see fig. 5, 7 and 17) to prevent the parent material of the nose of the upper jaw from being worn during use. The tip carrier 600 includes a blade side tip carrier 602 (see fig. 6 and 17), a guide side tip carrier 604 (see fig. 10), and a nose tip carrier 606 (see fig. 6, 10, and 17), forming a narrow tip portion 608. The forwardmost tip 609 of the tip carrier 600 is preferably rounded to reduce stress concentrations on the tip 608 during manufacturing and use. The spike insert 610 includes two

spike halves

620, 622 that are substantially mirror images of each other except for a respective connector aperture thereon (described later). One of the stab tip halves extending to the blade side of the tip portion will be referred to hereinafter as the blade side stab tip half 620, and the other of the stab tip halves extending to the guide side of the tip portion will be referred to hereinafter as the guide side stab tip half 622.

Fig. 15 illustrates various angled views of one embodiment of the blade side piercing tip half 620. FIG. 16 illustrates the same angular view of one embodiment of the leading side piercing tip half 622. The spike halves 620, 622 each include an outer side wall 630, the outer side wall 630 having a substantially vertical wear surface 632 and a substantially vertical inner support surface 634. The spike halves 620, 622 also each include a laterally inwardly projecting front wall 636, the front wall 636 having an outer curved wear surface 638 and an inner support surface 640. The spike halves 620, 622 further include laterally inwardly projecting bottom legs 642, the bottom legs 642 having bottom wear surfaces 644 and upper leg support surfaces 646. The spike halves 620, 622 also include an end bearing surface 648 and a lug 650, the lug 650 having an upper lug bearing surface 651 and a lower lug bearing surface 653. The outer periphery of the lug 650 is rounded to reduce stress concentration. A lower lug support face 653 extends rearwardly from the end support face 648, the purpose of which will be described in greater detail later in connection with fig. 22 and 23. The planar vertical wear surface 632 intersects the bottom wear surface 644 to form a shear edge 652. The intersection of the curved wear surface 638 of the front wall 636 and the bottom wear surface 644 forms a front piercing edge 654 (which may be chamfered).

As best shown in fig. 6, 10 and 17, the header bases 602, 604, 606 constitute a peripheral support edge surface 656, the peripheral support edge surface 656 being complementarily provided with the outer periphery of the

barbed halves

620, 622. According to the present embodiment, the width of the inner surface 640 of the laterally inwardly projecting front wall 636 and the upper surface 646 of the laterally inwardly projecting bottom leg 642 of each piercing

tip half

620, 622 is about one-half the width of the narrow end head 608 so that when the piercing tip halves 620, 622 are mounted on the end head mount 600, the inner support surfaces 634 of the side walls 630 of the piercing tip halves 620, 622 and the upper leg support surfaces 646 of the bottom leg 642 will abut against the respective support surfaces of the blade side end head mount 602, the guide side end head mount 604, and the front end head mount 606, respectively. In addition, the upper and lower lug support surfaces 651, 653 of the prong halves 620, 622 will abut the peripheral support edge surface 656 of the header 600. On the blade side of the tip section 601, either of the beveled ends 124 and 126 (depending on the orientation) of the upper shear blade insert 110 abuts against the back end support surface 648 of the blade side stab-tip half 620. Similarly, the blade-side bayonet halves 620 are rotatably restrained from rotating outwardly (as described below) by the blade insert 110 and the peripheral support edge surface 656, which couples with the upper and lower lug support surfaces 651, 653 of the blade-side end headstock. The guide-side barbed half 622 is rotatably restrained from movement by a peripheral support edge surface 656, which is coupled to the upper and lower lug support surfaces 651, 653 of the guide-side end header 604.

According to the present embodiment, when the piercing tip halves 620, 622 are mounted on the tip carrier 600, the narrow tip portion 608 is completely surrounded by the hardened steel piercing tip insert 610, thereby preventing the base material of the tip portion 601 from being worn during use.

The two

spike halves

620, 622 are secured to the narrow end head 608 by a threaded joint 670, in addition to being rotatably restrained by a peripheral support edge surface 656. In an embodiment the threaded joint is preferably a socket head cap screw. The two

spike halves

620, 622 include aligned apertures 660 through the respective outer side walls 632. A corresponding alignment hole 664 extends through the narrow end head 608. The coaxial counter bore 668 is located on the aligned holes 660 in the outer wall 632 of the blade side piercing tip half 620. An aligned hole 660 in the outer wall 632 of the guide side stab tip half 622 is tapped. The head of the nipple 670 is seated in the counterbore 668. The threaded end of the nipple 670 extends into the alignment hole 660 of the blade side stab tip half 620 and through the alignment hole 664 of the narrow head portion 608 and is threaded into the internally threaded alignment hole 660 of the pilot side stab tip half 622. It will be appreciated that the counter bores 668 of the two

spike halves

620, 622 and the internally threaded alignment holes 660 can be reversed as desired. Alternatively, a counterbore 668 is provided in the outer wall 632 of the two

spike halves

620, 622 for providing the head of the nipple 670 and a nut (not shown) on the other opposing spike half rather than the aligned holes 660 of one spike half. Referring to fig. 18 and 22, the aligned

holes

660, 664 are aligned along an arc coaxial with the leading edge of the stab tip 610 (i.e., the outer curved wear-resistant surface 638) to ensure a more uniform loading of the threaded joint 670.

According to the present embodiment, when the shear blade insert 110 is mounted on the upper jaw 40, the planar vertical wear surfaces 114, 116 of the shear blade insert 110 (depending on the mounting direction) are substantially coplanar with the vertical wear surfaces 632 of the blade-side stab-tip half 620, and the shear edge 122 of the shear blade insert 110 is substantially aligned with the shear edge 652 of the stab-tip insert 610. Likewise, when the shear blade insert 110 is mounted on the lower jaw 42, the planar vertical wear surfaces 114, 116 of the shear blade insert 110 (depending on the mounting direction) are substantially coplanar with the vertical wear surfaces 214 of the blade side guide blade insert 210, and the respective shear edges 122, 222 are substantially aligned. According to the present embodiment, the substantially coplanar vertical wear surfaces 114, 116, 632 and cutting

edges

122, 652 of the upper and stab tip inserts 610 are slightly offset laterally inwardly (preferably in the range of 0.01-0.05 inches) from the cutting

edges

122, 222 of the lower jaw's shear blade insert 110 and blade side guide blade insert 210 so that the upper cutting edges are not obstructed by the lower jaw's cutting edges when the upper jaw is moved into the slot 96 of the lower jaw 42 beyond the range of motion. Likewise, the cutting edge 652 of the guide side stab tip half 622 is offset laterally inward from the cutting edge 222 of the guide side guide blade insert 210, preferably in the range of 0.01-0.05 inches. Accordingly, the width of the puncturing tip insert 610 is less than the width between the opposing cutting edges 222 of the blade side and guide side guide blades 210 (preferably by a difference in the range of about 0.02-0.1 inches) so that the puncturing tip insert 610 can pass between the lower guide blades 210 when the upper jaw is closed into the slot 96 of the lower jaw 42. Shims may be inserted between each

insert

110, 210, 610 and its

respective insert seat

100, 200, 300, 500, 600 to maintain close tolerances of each cutting edge.

Fig. 18-22 are enlarged side views of the

jaws

40, 42 to better illustrate the relationship between the blade inserts 110, 210 and the stab tip insert 610, cross-blade insert 410 as the upper jaw is moved, i.e., when the upper jaw is moved from a fully open position (see fig. 18) to a fully closed position (fig. 21) at which the upper jaw reaches a maximum depth into the slot 96 of the lower jaw 42. FIG. 19 shows the upper jaw partially closed with the forward piercing edge 654 of the piercing tip insert 610 perpendicular to the ground. FIG. 20 shows the upper jaw at the intersection of the front piercing edge 654 and the lower jaw 42.

Tip wear plate 700 is secured (e.g., by welding) to the tip portion 601 of the upper jaw 40 above the stab tip insert 610 to prevent the upper jaw parent material from being worn during use. When the head wear plate 700 is worn, the head wear plate 700 can be removed and replaced with another wear plate 700. The wear plate 700 may be made of the same material as the parent material or may be made of hardened steel. As shown in fig. 20, the tip wear plate preferably extends along the tip a sufficient distance to ensure that the parent material of the tip is protected at least when the upper jaw 40 reaches a maximum depth into the lower jaw 42. In another embodiment, the piercing tip insert 610 may extend along the tip portion 601 to the maximum depth that the upper jaw extends into the lower jaw. The tip seat 600 is also extendable in this embodiment, with additional holes 660 for adequately restraining the longer piercing tip insert 610 to the narrow tip portion 608.

According to the present embodiment, the parent material of the tip portion 601 above the piercing tip insert 610 is more susceptible to wear than the hardened steel piercing tip insert 610. Therefore, without the wear plate 700, the tip 601 would wear until the upper edge of the stab insert 610 protrudes beyond the nose. If the upper edge of the piercing tip insert 610 protrudes outward from the tip 601, the protrusion may interfere with the material clamped within the jaws when the jaws are opened again or the upper jaw is retracted from the lower jaw. If the retraction force applied to the upper jaw is sufficient, the puncture tip insert may be pulled free of the head by the impeded material as the process shears the threaded connection or breaks the puncture tip insert. Thus, as described below, the tip 601 of the upper jaw is intended to reduce the risk of interference, even when the wear plate 700 is not mounted to the tip 601, or the wear plate itself is worn such that the base material of the tip is no longer protected by the wear plate.

Fig. 18 and 21 illustrate a preferred configuration of the tip portion 601 to avoid or minimize the incidence of snagging. The dashed-two dotted line designated by reference numeral 800 illustrates the arc formed by the forward most piercing edge 654 of the piercing tip insert 610 as the upper jaw is moved through its range of motion. The central axis of arc 800 to jaw pivot 60 is radius R1. The outermost periphery of the tip 601 is from the front piercing edge 654 of the piercing tip 610 to the end of the tip wear plate 700 or to the tip corresponding to the maximum depth of penetration of the tip 601 into the lower jaw. The outermost periphery of the tip 601 is designed as a generally rounded tip arc 802 that increases in distance from the front piercing edge arc 800. The radius R2 of tip arc 802 is less than radius R1 so that the radial distance from the central axis of jaw pivot 60 to the tip along tip 601 or tip arc 802 is progressively smaller relative to the piercing edge arc 800. By another approach, the distance of the piercing edge arc 800 from the tip arc 802 decreases along the tip 601 or tip arc 802 from the leading piercing edge arc 654. With this construction, tip 601 can only make contact at the leading piercing edge 654, thereby avoiding or reducing the likelihood of the tip 601 being scratched along with an object penetrating the piercing tip 610, minimizing tip wear. In addition, since the distance between the tip and the piercing edge arc 800 increases, even if the tip base material is worn and the leading edge of the piercing tip insert 610 protrudes outward from the tip worn base material, the possibility of the material being gripped by the jaws being blocked is reduced.

Further, the puncture tip holder 600 and puncture tip insert 610 serve to hold the puncture tip in place if the protruding edge of the puncture tip becomes snagged or the upper jaw becomes clogged with material gripped by the jaws. For example, as shown in fig. 22, the hatched area 900 indicates that material is trapped or embedded between the stab tip insert 610 and the wear surface of the leading shear blade insert 210, wherein the stab tip insert 610 and the shear blade insert 210 cause the upper jaw to be snapped into the slot 96 of the lower jaw 42 so that the upper jaw 40 cannot be retracted or re-opened. The retraction force F of the upper jaw 40 (applied by the hydraulic actuator 30 pulling the upper jaw) is used to pull the puncture tip insert 610 in a direction perpendicular to the radial line 806, the radial line 806 extending from the center axis of the jaw pivot 60 toward the midpoint of the resistive material 900. Thus, any bearing surface that is less than 90 degrees from the radial line 806 is subject to a retraction force F according to the present embodiment. The rearwardly projecting lugs 650 thus ensure that the bearing surface can withstand the retraction force F by piercing the tip insert 610.

As shown in fig. 22, the support surfaces indicated by arrows R opposite the peripheral support edge surface 656 of the tip carrier 600 are subjected to a retraction force F due to the lower lug support surface 653 forming an angle with the radial line 806 of less than 90 degrees. Likewise, the inner surface 640 of the front wall 636 bears against the tip seat 606 as indicated by arrow R to withstand the retraction force F. In this manner, the bearing or resistive force R reduces the shear force applied to the fitting 670 by the retraction force F, thereby preventing or minimizing breakage of the puncture tip insert 610 by pulling out of the tip or otherwise.

In addition, because the holes 660 in the stab tip insert 610 are aligned along nose arc 804, and the radius R3 of nose arc 804 is smaller than the radius R2 of nose arc 802 but is concentric with nose arc 802, all of the joints 670 are able to withstand more uniform loads, thereby further reducing the shear stress applied to either joint and avoiding stress concentrations that would cause the joints to shear or the stab tip insert to break.

Another embodiment is shown in FIG. 23, wherein the hatched area 902 indicates that material is trapped between the stab tip insert 610 and the cross-blade insert 410. In this embodiment, assuming that the retraction force F is located at the front piercing tip edge 654, the retraction force F in turn pulls the piercing tip in a direction perpendicular to the radial line 806, which radial line 806 extends from the center axis of the jaw pivot 60 toward the midpoint of the hindered material. The retraction force F causes the puncture tip insert 610 to roll outward or away from the tip portion 601 as shown by arrow 810. However, the resistive force R causes the upper lug support surface 651 of the tip carrier 600 in combination with the peripheral support edge surface 656 to resist outward rotation of the puncture tip insert 610, thereby reducing shear forces on the adapter 670 and preventing or reducing stress cracking of the puncture tip insert 610.

Fig. 24 shows an example of the retraction force F acting on the upper edge of the piercing tip insert 610 in the case where the tip 601 is worn to form a ledge that holds the material up as described above. This is unlikely to occur given the construction of the tip 601 with the tip arc 802 being a gradual increase in distance from the front piercing edge arc 800, but if the tip is worn to create a ledge that can impede material, the resistance to the retraction force F causes the upper lug support surface 651 of the tip seat 600 to cooperate with the peripheral support edge surface 656 to impede outward rotation of the piercing edge, thereby reducing shear forces on the joint 670 and preventing or reducing stress cracking of the piercing tip insert 610.

In view of the foregoing, it will be appreciated by those skilled in the art that the present invention can be made and used as described herein without departing from the spirit and scope of the invention as defined by the appended claims. Any modifications, generalizations, and features of the embodiments described herein will be understood by those skilled in the art. Accordingly, the present invention is not limited to the embodiments described herein and shown in the drawings, but is to be covered by the appended claims without departing from the spirit and scope of the invention.

Claims

1. A demolition shear comprising:

an upper jaw rotatable through a range of motion between an open position and a closed position, a forwardmost portion of the upper jaw defining an end head having a blade side, a guide side, a bottom side and a front side;

a hardened steel piercing tip insert mounted to the header, the piercing tip insert comprising:

a blade side outer planar side wall surface;

a guide side outer plane side wall surface;

a bottom surface extending laterally between a bottom side of said insert side outer planar sidewall surface and a bottom side of said guide side outer planar sidewall surface;

a curved outer front wall surface extending laterally between a front side of said blade side outer planar side wall surface and a front side of said guide side outer planar side wall surface, said curved outer front wall surface having a front wall arc radius;

thereby, the tip portion is completely surrounded and protected by the puncture tip insert by the insert-side outer planar side wall surface along the insert side of the tip portion, the guide-side outer planar side wall surface along the guide side of the tip portion, the bottom surface along the bottom side of the tip portion, and the curved outer front wall surface along the front side of the tip portion.

2. The demolition shear of claim 1, wherein: the piercing tip insert includes a first piercing tip portion and a second piercing tip portion.

3. The demolition shear of claim 2, wherein: the first and second spike portions are formed by mating spike halves of the spike inserter.

4. The demolition shear of claim 1, wherein:

the side wall surface of the outer plane of the blade side is intersected with the bottom surface to form a shear blade, and the curved outer front wall surface is intersected with the bottom surface to form a front stab blade.

5. The demolition shear of claim 4, wherein: the front piercing edge defines a piercing edge arc having a radius greater than the front wall arc radius as the upper jaw rotates within the range of motion such that the curved outer front wall surface is progressively further from the piercing edge arc.

6. The demolition shear of claim 1, wherein: each of the blade side outer plane side wall surface and the guide side outer plane side wall surface includes a plurality of connection holes, each of the connection holes is used for mounting a threaded connector so that the bayonet plug-in is detachably fixed to the head portion by the threaded connector, the connection holes are concentrically arranged along a connection hole arc radius, and the connection hole arc radius is smaller than the front wall arc radius.

7. The demolition shear of claim 5, comprising:

a tip wear plate having a tip wear plate arc with a tip wear plate radius that is substantially the same as the front wall arc radius such that the tip wear plate arc is progressively further away from the stab edge arc.

8. The demolition shear of claim 1, wherein: also comprises at least one shearing blade which is arranged on the upper jaw.

9. The demolition shear of claim 8, wherein: the lower jaw includes at least one shearing blade.

10. The demolition shear of claim 9, wherein: the lower jaw further comprises at least one guide blade.

11. The demolition shear of claim 10, wherein: the lower jaw further comprises at least one cross blade.

12. A barbed insert for a demolition shear, the demolition shear comprising an upper jaw rotatable with respect to a lower jaw through a range of motion between an open position and a closed position, a forwardmost portion of the upper jaw defining an end head having a blade side, a guide side, a bottom side, and a front side; the spike insert comprises:

a blade side outer planar side wall surface;

a guide side outer plane side wall surface;

thus, when the puncturing tip insert is mounted in the tip portion, the tip portion is completely surrounded and protected by the puncturing tip insert by the blade-side outer planar side wall surface along the blade side of the tip portion, the guide-side outer planar side wall surface along the guide side of the tip portion, the bottom surface along the bottom side of the tip portion, and the curved outer front wall surface along the front side of the tip portion.

13. The piercing tip insert of claim 12, wherein: the piercing tip insert includes a first piercing tip portion and a second piercing tip portion.

14. The piercing tip insert of claim 13, wherein: the first and second spike portions are formed by mating spike halves of the spike inserter.

15. The piercing tip insert of claim 12, wherein: the side wall surface of the outer plane of the blade side is intersected with the bottom surface to form a shear blade, and the curved outer front wall surface is intersected with the bottom surface to form a front stab blade.

16. The piercing tip insert of claim 12, wherein: each of the blade side outer plane side wall surface and the guide side outer plane side wall surface includes a plurality of connection holes, each of the connection holes is used for mounting a threaded connector so that the bayonet plug-in is detachably fixed to the head portion by the threaded connector, the connection holes are concentrically arranged along a connection hole arc radius, and the connection hole arc radius is smaller than the front wall arc radius.

17. A blade set comprising the piercing tip insert of any of claims 12-16, and further comprising at least one shear blade adapted to be mounted to the upper jaw of the demolition shear.

18. A blade set as claimed in claim 17 wherein: further comprising at least one shear blade adapted to be mounted to the lower jaw of the demolition shear.

19. A blade set as claimed in claim 17 wherein: further comprising at least one guide blade adapted to be mounted to the lower jaw of the demolition shear.

20. A blade set as claimed in claim 18 wherein: further comprising at least one guide blade adapted to be mounted to the lower jaw of the demolition shear.

21. A blade set as claimed in claim 17 wherein: further comprising at least one cross-blade adapted to be mounted to the lower jaw of the demolition shears.

22. A blade set as claimed in claim 18 wherein: further comprising at least one cross-blade adapted to be mounted to the lower jaw of the demolition shears.

23. A blade set as claimed in claim 19 wherein: further comprising at least one cross-blade adapted to be mounted to the lower jaw of the demolition shears.

24. A blade set as claimed in claim 20 wherein: further comprising at least one cross-blade adapted to be mounted to the lower jaw of the demolition shears.