Adjustment mechanism for adjusting the jaws of scissors

Abstract

Hydraulic shears (100) with: a first jaw (102) with a first and second side wall (112, 114) defining a first opening (118) and a second opening (120) through the same; a second jaw (104) arranged between the first and second side wall (112, 114), the second jaw (104) comprising a third opening (122); a pivot pin (106) extending through the openings (118, 120, 122) to pivotally connect the first and second jaws (102, 104); and an adjusting mechanism (130) which is coupled to the first jaw (102), the second jaw (104) and the pivot pin (106), wherein the adjusting mechanism (130) is designed to adjust a position of the second jaw (104) on the pivot pin (106) slidably with respect to the first and second side walls (112, 114); the pivot pin (106) comprises: a head section (124) which is arranged in the first opening (118) on the first side wall (112); and a shaft section (126) extending away from the head section (124) and comprising a threaded end (128) arranged at the second opening (120) of the second side wall (114); wherein the first side wall (112) comprises a slotted groove (132) adjacent to the first opening (118) therein, the slotted groove (132) being arranged transversely to the pivot pin (106); wherein the adjusting mechanism (130) comprises a locking element (134) which is connected to the head section (124) of the pivot pin (106) and is arranged in the slot groove (132), wherein the locking element (134) is configured to limit a rotational movement of the pivot pin (106) with respect to the first and second jaw (102, 104); the adjustment mechanism (130) further comprises: a bushing (140) which is slidably mounted on the shaft section (126) of the pivot pin (106) and is arranged between the first side wall (112) and the second jaw (104); and a nut (154) which is adjustable in engagement with the threaded end (128) of the pivot pin (106) and releasably engaged with the second side wall (114); the cylinder liner (140) comprises: a collar section (144) which is arranged in an adjacent relationship with the head section (124) of the pivot pin (106); and a flange section (142) which is arranged in an adjacent relationship with the second jaw (104); and wherein the flange section (142) and the first side wall (112) further comprise a pair of coaxial holes (146, 148) wherein the holes (146, 148) are designed to slidably receive one or more locking pins (150, 152) in order to secure a position of the bushing (140) in relation to the first jaw (102) in a rotationally fixed manner.

Description

Technical field

[0001] The present disclosure relates to a pair of scissors, for example hydraulic scissors, and in particular to an adjusting mechanism for adjusting the jaws of the scissors. background

[0002] Shears on heavy construction equipment comprise a pair of jaws with one or more shear blades attached to them. The jaws may include a pivoting jaw and a fixed jaw. The jaws may be mounted on a pivot pin, allowing one jaw to pivot relative to the fixed jaw. The pivoting jaw moves its associated shear blade relative to the shear blade on the fixed jaw to deliver shearing and crushing forces to an object. Such shears may also employ spacer plates and low-friction plates mounted on the pivot pin and positioned adjacent to each jaw. The spacer plates are designed to maintain a predetermined degree of tolerance between the jaws, while the low-friction plates reduce friction between the jaws during operation.

[0003] During operation, the shears can be opened and closed multiple times to shear objects. However, with frequent opening and closing of the jaws over an extended period, the spacer plates and low-friction plates can be subject to wear from the jaws. This wear can cause play in the spacer plates and low-friction plates, making the pivoting jaw prone to shifting or wobbling on the pivot pin during operation. Consequently, subsequent use of the shears may require increased effort from the jaws to shear or shred objects.

[0004] One way to compensate for play in the stacked plates mounted on the pivot pin is to replace the plates. However, replacing all the plates can require operators to disassemble the jaws and install new plates. This also incurs additional costs for the replacement process and downtime of the shear. Furthermore, the procedure can be laborious and cumbersome, and expensive tools are required to separate the jaws and reattach them in a pivot position.

[0005] US 2011 / 0225829 A1 discloses a configurable, heavy-duty shear / breaker / demolition tool comprising an upper jaw, a lower jaw, and a pivot assembly connecting the upper and lower jaws. A configurable number of tooth holders are mounted on the upper and lower jaws. A configurable number of teeth are detachably mounted on the tooth holders. A configurable number of shear blade holders are mounted on the upper and lower jaws. A configurable number of shear blades are detachably mounted on the shear blade holders.

[0006] DE 696 11 636 T2 discloses a cutting device, in particular for cutting metals or concrete, which is intended to be mounted at the end of a boom of a construction machine, and comprises the following: on the one hand, a device which is suitable for being rigidly connected to the boom, and on the other hand, a complementary tool which is mounted on the device and rotatably guided, wherein it is actuated by a drive cylinder of the construction machine, and wherein the device's rotary guide means interact with a damping element in the closed position corresponding to cutting and with a pressing device which ensures a lateral distance between the actuating ends of the device and the tool in order to prevent a lateral distance between the cutting ends of the device and the tool during cutting.

[0007] DE 690 20 527 T2 discloses a demolition attachment for an excavator. The demolition attachment comprises a support frame with rigid mounting elements that can be attached to a boom, two demolition jaws that are rotatable relative to the support frame and to each other, and that can be moved into an open and a closed position, and drive means that move the demolition jaws relative to each other. The two demolition jaws are attached to a common pivot bearing, which rotatably connects these demolition jaws to each other and is interchangeably and rotatably attached to the support frame, such that they move about a single axis defined by the pivot bearing along specific working path arcs. The pivot bearing has coupling means that hold the demolition jaws together when the pivot bearing and the demolition jaws are removed from the support frame. Summary of Revelation

[0008] According to one aspect, the present disclosure provides a hydraulic shear comprising a first jaw, a second jaw, a pivot pin, and an adjustment mechanism. The first jaw includes a first and second side wall, which define a first and second opening through the same. The second jaw is arranged between the first and second side walls and includes a third opening. The pivot pin extends through the first, second, and third openings to pivotally connect the first and second jaws. The adjustment mechanism is coupled to the first jaw, the second jaw, and the pivot pin. The adjustment mechanism slidably sets a position of the second jaw on the pivot pin relative to the first and second side walls of the first jaw.

[0009] According to another aspect, the present disclosure provides a pair of scissors comprising a fixed jaw, a pivoting jaw, a pivot pin extending through openings in the fixed and pivoting jaws, and an adjustment mechanism. The adjustment mechanism is coupled to the fixed jaw, the pivoting jaw, and the pivot pin. The adjustment mechanism slidably sets a position of the pivoting jaw on the pivot pin relative to the fixed jaw.

[0010] Further features and aspects of this revelation will become clear from the following description and the accompanying drawings. Brief description of the drawings Fig. Figure 1 is a perspective front view of a pair of scissors in accordance with an exemplary embodiment of the present disclosure; Fig. 2 is an exploded view of the example scissors of Fig. 1; Fig. Figure 3 is a side view of the scissors and shows a threaded nut of an adjustment mechanism, which in the exemplary scissors of Fig. 1 and Fig. 2 is used; and Fig. Figure 4 is a sectional view of the scissors and shows the operation of the adjustment mechanism. Detailed description

[0011] The present disclosure relates to an adjustment mechanism for adjusting the jaws of a pair of scissors. Fig. Figure 1 shows a perspective front view of a shear 100 in accordance with an exemplary embodiment of the present disclosure. In one embodiment, the shear 100 may be of a type typically used on heavy construction equipment for shearing earth materials, tree trunks, or building materials. In another embodiment, the shear 100 may be a hydraulic shear configured to be powered hydraulically using actuators and pin connections. In yet another embodiment, the shear 100 may be an electrically powered shear. Although the description focuses on hydraulic shears, it is clear that the apparatus and method can be applied similarly to other types of shears 100.

[0012] Fig. Figure 2 shows an exploded view of the hydraulic shear 100. The hydraulic shear 100 comprises a first jaw 102, a second jaw 104, and a pivot pin 106. In one embodiment, as shown in Fig. As shown in Figure 2, the first jaw 102 is a fixed jaw, while the second jaw 104 is a pivotable jaw. In one embodiment, the first and second jaws 102, 104 comprise one or more shear blades 108, 110. The shear blades 108, 110 can be configured to exert shear forces on an object (not shown).

[0013] The first jaw 102 comprises a first side wall 112 and a second side wall 114. The first and second side walls 112, 114 extend rearward and forwardward to jointly form the first jaw 102. The first and second side walls 112, 114 define a recess 116 between them. The second jaw 104 is positioned between the first and second side walls 112, 114 and is partially located within the recess 116 between the first and second side walls 112, 114.

[0014] Furthermore, the first side wall 112 and the second side wall 114 define a first opening 118 and a second opening 120 through the same. In one embodiment, as shown in Fig. Figure 2 shows the first opening 118 and the second opening 120 arranged coaxially with each other. The second jaw 104 includes a third opening 122, which is arranged coaxially relative to the first and second openings 118, 120. The pivot pin 106 extends through the first, second, and third openings 118, 120, and 122 to pivotally connect the first and second jaws 102, 104. In one embodiment, as shown in Fig. Figure 2 shows the pivot pin 106 comprising a head section 124 and a shaft section 126. The head section 124 is located in the first opening 118 on the first side wall 112. The shaft section 126 extends from the head section 124 and includes a threaded end 128, which is located at the second opening 120 of the second side wall 114. Thus, the second jaw 104 is slidably mounted on the pivot pin 106 and can pivot relative to the fixed first jaw 102.

[0015] The hydraulic shear 100 further comprises an adjusting mechanism 130, which is coupled to the pivot pin 106, the first jaw 102 and the second jaw 104. The adjusting mechanism 130 is designed to adjust the position of the second jaw 102 on the pivot pin 106 in relation to the first and second side walls 112, 114 of the first jaw 102, as will be explained in more detail in this disclosure.

[0016] In one embodiment, as described in Fig. Figure 2 shows the first side wall 112 having a slotted groove 132 adjacent to the first opening 118 therein. The slotted groove 132 is arranged transversely to the pivot pin 106. In one embodiment, as shown in Fig. Figure 2 shows the adjusting mechanism 130 comprising a locking element 134, which is connected to the head section 124 of the pivot pin 106. The locking element 134 is arranged in the slot 132 and is designed to limit rotational movement of the pivot pin 106 relative to the first and second jaws 102, 104.

[0017] In one embodiment, as described in Fig. Figure 2 shows the scissors 100 and an end cap 136, which is detachably attached to the first side wall 112. The end cap 136 is positioned so that it points towards the locking element 134 and is detachably attached to the first side wall 112 using one or more threaded fastening elements 138, such as hex screws.

[0018] In another embodiment, as described in Fig. Figure 2 shows the adjusting mechanism 130 and a bushing 140, which is slidably mounted on the shaft section 126 of the pivot pin 106. The bushing 140 is arranged between the first side wall 112 of the first jaw 102 and the second jaw 104. The bushing 140 comprises a flange section 142 and a collar section 144, which are arranged in a stepped relationship to each other. The flange section 142 is designed to bear against the second jaw 104, while the collar section 144 is designed to bear against the head section 124 of the pivot pin 106 on a side opposite the locking element 134.

[0019] In another embodiment, as described in Fig. Figure 2 shows the flange section 142 of the bushing 140 and the first side wall 112, further comprising a pair of holes 146, 148 arranged coaxially relative to each other. The holes 146, 148 are designed to slidably receive a pair of locking pins 150, 152. The locking pins 150, 152 are designed to secure the bushing 140 against rotation relative to the first side wall 112.

[0020] In one embodiment, as described in Fig. Figure 2 shows the adjusting mechanism 130 and a nut 154, which is arranged on the second side wall 114 of the first jaw 102. The nut 154 is detachably engaged with the second side wall 114 and adjustably engaged with the threaded end 128 of the pivot pin 106. In one embodiment, the nut 154 comprises a cap section 156 and a flange section 158, which extends radially from the cap section 156. The cap section 156 is substantially longer relative to the flange section 158. The cap section 156 of the nut 154 comprises an internal thread 160, which is designed to engage screwably with the threaded end 128 of the pivot pin 106. Furthermore, the second side wall 114 and the flange section 158 of the nut 154 include one or more holes 162, 164 designed to accommodate the threaded fastening elements 166.The threaded fastening elements 166 detachably fasten the flange section 158 to the second side wall 114 and thus detachably engage the nut 154 with the first jaw 102.

[0021] In one embodiment, as in Fig. Figure 2 shows that the shears 100 further comprise one or more spacer plates 168 and low-friction plates 170, 172, which are positioned on the pivot pin 106 and arranged adjacent to the first and second jaws 102, 104. In an exemplary embodiment, as shown in Fig. Figure 2 shows that the shear 100 comprises a spacer plate 168 and two low-friction plates 170 and 172. The spacer plate can be arranged to abut the second jaw 104 and a first low-friction plate 170, while a second low-friction plate 172 can be arranged to abut the flange section 142 of the bushing 140 and the second jaw 104. The low-friction plates 170 and 172 can be designed to reduce the amount of friction experienced by the second jaw 104 while the second jaw 104 pivots relative to the stationary second side wall 114 and the stationary bushing 140.

[0022] In the preceding embodiment, the adjusting mechanism 130 can be configured to superimpose the spacer plates 168, the low-friction plates 170, 172, and the second jaw 104 substantially proximal to the second side wall 114 such that the second jaw 104 is slidably positioned on the pivot pin 106 and brought closer to the blades 108 on the second side wall 114. Furthermore, the second jaw 104 is simultaneously configured to maintain an upright position relative to the pivot pin 106. In alternative embodiments, however, the adjusting mechanism 130 can slidably adjust the position of the second jaw 104 closer to the second side wall 114 of the first jaw 102, depending on the position of the shear blades 108, 110 on the first and second jaws 102, 104. In an exemplary embodiment, as shown in the Fig. 2 and Fig. As shown in Figure 3, the slot 132 on the first side wall 112 and the locking element 134 arranged therein are located around the section plane AD, while the threaded fastening elements 138, which releasably engage the end cap 136 with the first side wall 112, can be arranged in the section plane BD. Furthermore, the locking pins 150, 152 disclosed herein can be located around the section plane CD. In addition, the threaded fastening elements 166, which releasably engage the nut 154 with the second side wall 114, can be arranged in the section plane BD. Although the section planes AD, BD, and CD are disclosed herein, these planes are purely exemplary and are therefore not intended to limit this disclosure in any way. Any angled cutting planes can be used to arrange the slot 132, the locking pins 150, 152 and the threaded fastening elements 138, 166.

[0023] In another embodiment, as in Fig. As shown in Figure 4, the thickness 174 of the locking element 134 is less than the depth 176 of the slot 132. Furthermore, the length 178 of the shaft section 126 of the pivot pin 106 is less than the width 180 of the recess 116, which is defined between the first and second side walls 112, 114. Therefore, the pivot pin 106 is axially restricted and restricted in its rotation by the internal thread 160 of the nut 154 on the cap section 156 of the nut 154, the slot 132, and the end cap 136. Furthermore, the rotation of the bushing 140 is restricted by the locking pins 150, 152, which are slidably arranged within the holes 146, 148 on the bushing 140 and the first side wall 112.

[0024] Prolonged operation of the shears, with repeated opening and closing of the jaws to achieve shearing, can cause wear on the spacer plate and the low-friction plates 170, 172, thus reducing the thickness of the spacer plates 168 and / or the low-friction plates 170, 172. This reduction in thickness can cause play between the second jaw 104 and the adjacent spacer plates 168 and the low-friction plates 170, 172. This play can make the second jaw 104 movable on the pivot pin 106 and, in some cases, can make the second jaw 104 prone to wobbling on the pivot pin 106.

[0025] With reference to Fig.4. Operation of the adjusting mechanism 130 is initiated to position the second jaw 104 slidably relative to the first and second side walls 112, 114 of the first jaw 102, while the spacer plates 168, the low-friction plates 170, 172, and the second jaw 104 are slidably superimposed, essentially proximal to the second side wall 114 of the first jaw 102. The threaded fasteners 166 on the nut 154 are loosened to disengage the nut 154 from the second side wall 114 of the first jaw 102. The nut 154 is then rotated clockwise in a direction 182 (viewed from the left in the case of a right-hand internal thread 160 of the nut 154). In alternative embodiments, however, the nut 154 can be rotated in a counterclockwise direction (as seen from the left in the case of a left-hand internal thread 160 of the nut 154).

[0026] The clockwise rotation of the nut 154 in direction 182 causes an axial displacement 184 of the pivot pin 106 towards the nut 154, and consequently the locking element 134 on the head section 124 of the pivot pin 106 is also axially displaced away from the end cap 136 and towards the slot 132. As a result, the head section 124 of the pivot pin 106 displaces the collar section 144 of the bushing 140, which causes the flange section 142 of the bushing 140 to displace the low-friction plates 170, 172, the spacer plates 168, and the second jaw 104 towards the second side wall 114 of the first jaw 102.

[0027] Moving the spacer plates 168, the low-friction plates 170, 172, and the second jaw 104 towards the second side wall 114 can reduce any play between the spacer plates 168, the low-friction plates 170, 172, and the second jaw 104. Furthermore, this reduction in play can clamp the spacer plates 168, the low-friction plates 170, 172, and the second jaw 104 together against the second side wall 114 of the first jaw 102. Furthermore, the clamping of the spacer plates 168, the low-friction plates 170, 172 and the second jaw 104 on the second side wall 114 of the first jaw 102 can in turn make the second jaw 104 upright on the pivot pin 106 and substantially proximal to the cutting blade 108 on the second side wall 114.

[0028] After the play has been reduced, the threaded fasteners 166 on the nut 154 can be repositioned within the holes 162, 164 to secure the nut 154 to the second side wall 114 and to secure the pivot pin 106 and the second jaw 104 in their position relative to the first jaw 102. As further disclosed herein, the second jaw 104 can be configured to maintain a substantially upright position on the pivot pin 106 until further wear occurs on the spacer plates 168 and / or the low-friction plates 170, 172.

[0029] For the purpose of illustration and clarification, various embodiments presented herein disclose by way of example different dimensional parameters. Furthermore, the operation of the adjustment mechanism 130 has been explained with reference to the exemplary embodiments. It should be noted, however, that the embodiments disclosed herein are purely exemplary and thus do not limit this disclosure in any way. Therefore, numerous modifications to the dimensional parameters disclosed herein can be made without deviating from the scope of this disclosure. Commercial applicability

[0030] Shears used on heavy construction equipment are typically subjected to high reaction forces from the objects being sheared. Furthermore, the repeated opening and closing of the jaws during prolonged operation can cause wear on the spacer plates and low-friction plates. This wear can create play in the spacer plates and low-friction plates, making the pivoting jaw prone to shifting or wobbling on the pivot pin during operation. Consequently, subsequent use of the shears may require increased effort from the jaws to shear or crush the objects.

[0031] One way to compensate for the play in the stacked plates arranged on the pivot pin is to replace the plates.

[0032] Replacing the plates entirely can require operators to disassemble the jaws and install new plates. This incurs additional costs for the replacement process and downtime of the shears. Furthermore, the procedure can be laborious and cumbersome, requiring expensive tools to separate and reattach the jaws. Additionally, conventional methods for adjusting the relative position of the jaws can result in significant shear downtime, thus negatively impacting the overall cost-effectiveness of the shears operation.

[0033] By implementing the present adjustment mechanism 130 in scissors 100, wear on the spacer plates 168 and the low-friction plates 170, 172 can be compensated for by positioning the second jaw 104 slidably relative to the first jaw 102 such that the clearance between the first and second jaws 102, 104 is reduced. Furthermore, the adjustment mechanism 130 disclosed herein extends the service life of the spacer plates 168 and the low-friction plates 170, 172 by allowing an operator to consider the remaining service life of the spacer plates 168 and the low-friction plates 170, 172 before deciding to replace them entirely. Therefore, the adjustment mechanism 130 can reduce additional costs that were previously incurred by replacing the spacer plates 168 and the low-friction plates 170, 172.

[0034] To adjust the relative positioning of the jaws 102 and 104 and maintain a predetermined shearing force of the shears 100, the nut 154 can be disengaged from the first jaw 102 by loosening the threaded fasteners 166 and then rotating them to move the second jaw 104 slidably on the pivot pin 106. This method of clamping the spacer plates 168, the low-friction plates 170 and 172, and the second jaw 104 together to adjust its position can be simple and quick, requiring minimal effort. Therefore, using the adjustment mechanism 130 can reduce the shears' downtime and thus improve the overall efficiency of the shears' operation.

Claims

[1] Hydraulic shears (100) with: a first jaw (102) with a first and second side wall (112, 114) defining a first opening (118) and a second opening (120) through the same; a second jaw (104) arranged between the first and second side wall (112, 114), the second jaw (104) comprising a third opening (122); a pivot pin (106) extending through the openings (118, 120, 122) to pivotally connect the first and second jaws (102, 104); and an adjusting mechanism (130) which is coupled to the first jaw (102), the second jaw (104) and the pivot pin (106), wherein the adjusting mechanism (130) is designed to adjust a position of the second jaw (104) on the pivot pin (106) slidably with respect to the first and second side walls (112, 114); the pivot pin (106) comprises: a head section (124) which is arranged in the first opening (118) on the first side wall (112); and a shaft section (126) extending away from the head section (124) and comprising a threaded end (128) arranged at the second opening (120) of the second side wall (114); wherein the first side wall (112) comprises a slotted groove (132) adjacent to the first opening (118) therein, the slotted groove (132) being arranged transversely to the pivot pin (106); wherein the adjusting mechanism (130) comprises a locking element (134) which is connected to the head section (124) of the pivot pin (106) and is arranged in the slot groove (132), wherein the locking element (134) is configured to limit a rotational movement of the pivot pin (106) with respect to the first and second jaw (102, 104); the adjustment mechanism (130) further comprises: a bushing (140) which is slidably mounted on the shaft section (126) of the pivot pin (106) and is arranged between the first side wall (112) and the second jaw (104); and a nut (154) which is adjustable in engagement with the threaded end (128) of the pivot pin (106) and releasably engaged with the second side wall (114); the cylinder liner (140) comprises: a collar section (144) which is arranged in an adjacent relationship with the head section (124) of the pivot pin (106); and a flange section (142) which is arranged in an adjacent relationship with the second jaw (104); and wherein the flange section (142) and the first side wall (112) further comprise a pair of coaxial holes (146, 148) wherein the holes (146, 148) are designed to slidably receive one or more locking pins (150, 152) in order to secure a position of the bushing (140) in relation to the first jaw (102) in a rotationally fixed manner. [2] Hydraulic shear (100) according to claim 1, further comprising one or more spacer plates (168) and low-friction plates (170, 172) positioned on the pivot pin (106) and arranged adjacent to the first and second jaws (102, 104). [3] Hydraulic shear (100) according to claim 2, wherein the adjusting mechanism (130) is further configured to allow the spacer plates (168), the low-friction plates (170, 172) and the second jaw (104) to be slidably placed one on top of the other substantially proximal to either the first side wall (112) or the second side wall (114) of the first jaw (102). [4] Hydraulic shear (100) according to claim 1, wherein a thickness (174) of the locking element (134) is less than a depth (176) of the slot groove (132).

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