Claims:1. A link clamp assembly for holding a workpiece comprising:
a housing with a bore defining a longitudinal axis;
a piston received in the bore and moveable between retracted and extended positions along the longitudinal axis;
a clamping lever pivotally connected to one end of the piston, the clamping lever structured and arranged to rotate relative to the housing in a single plane substantially parallel with the longitudinal axis of the bore;
first and second link plates pivotally connected to the clamping lever structured and arranged to move the clamping lever to a clamped position when the piston is moved to the extended position, to move the clamping lever to a released position when the piston is moved to the retracted position; and
a hand-actuated quick change clamping assembly releasably secured to the clamping lever structured and arranged to releasably secure the clamping lever to the piston and the first and second link plates.
2. The link clamp assembly of Claim 1, wherein the quick change clamping assembly comprises a cover structured and arranged to be engaged to the top of the clamping lever and a hand-actuated quick change lock pin structured and arranged to secure the cover to the top of the clamping lever.
3. The link clamp assembly of Claim 2, wherein the hand-actuated quick change lock pin comprises a cover abutment face contacting a top surface of the cover and an engagement portion extending therefrom structured and arranged to be received in an engagement hole on the top of the clamping lever.
4. The link clamp assembly of Claim 3, wherein the engagement portion of the hand-actuated quick change lock pin comprises two radially moveable locking balls structured and arranged to engage a locking recess of the engagement hole of the clamping lever.
5. The link clamp assembly of Claim 4, wherein the two radially moveable locking balls are circumferentially spaced in the engagement portion of the hand-actuated quick change lock pin.
6. The link clamp assembly of Claim 4, wherein the hand-actuated quick change lock pin comprises a spring biased thumb plunger in a central longitudinal bore, the spring biased plunger being axially moveable in the central longitudinal bore.
7. The link clamp assembly of Claim 6, wherein the spring biased thumb plunger comprises a smaller diameter central portion and a larger diameter plunger bulb.
8. The link clamp assembly of Claim 7, wherein the larger diameter plunger bulb urges the two radially moveable locking balls radially outward when the larger diameter plunger bulb is in radial alignment with the two radially moveable locking balls, and the smaller diameter central portion retracts the two radially moveable locking balls radially inward when the smaller diameter central portion is in radial alignment with the two radially moveable locking balls.
9. The link clamp assembly of Claim 8, wherein the two radially moveable locking balls contact the locking recess of the engagement hole of the clamping lever in the radially outward position.
10. The link clamp assembly of Claim 2, wherein the cover comprises first and second front interior sidewall portions retaining a link assembly pin therebetween and first and second rear interior sidewall portions retaining a piston pin therebetween.
11. The link clamp assembly of Claim 10, wherein the first and second rear interior sidewall portions are closer together than the first and second front interior sidewall portions.
12. The link clamp assembly of Claim 10, wherein the first and second front interior sidewall portions receive a first pin, the first and second link plates and the clamping lever therebetween, and the first and second rear interior sidewall portions receive a second pin, the piston and the clamping lever therebetween.
13. The link clamp assembly of Claim 3, wherein the cover comprises a through hole that is aligned with the engagement hole of the clamping lever, the engagement portion of the hand-actuated quick change lock pin is inserted through the through hole of the cover and into the engagement hole of the clamping lever.
14. The link clamp assembly of Claim 1, wherein the clamping lever is pivotally connected to the piston by a first pin and the first and second link plates are coupled with the clamping lever by a second pin.
15. The link clamp assembly of Claim 14, wherein the first and second pins are secured in the clamping lever by the quick change assembly.
16. A link clamp quick change clamping assembly comprising:
a clamping lever pivotally connected to a piston of a link clamp base;
a link assembly pin structured and arranged to couple the clamping lever to first and second link plates of the link clamp base;
a piston pin structured and arranged to couple the clamping lever to the piston of the link clamp base;
a cover releasingly engageable to the top of the clamping lever comprising first and second front interior sidewall portions receiving the link assembly pin, the first and second link plates and the clamping lever therebetween, and first and second rear interior sidewall portions receiving the piston pin, the piston and the clamping lever therebetween; and
a hand-actuated quick change lock pin structured and arranged to secure the cover to the top of the clamping lever.
17. The link clamp quick change clamping assembly of Claim 16, wherein the hand-actuated quick change lock pin comprises a cover abutment face contacting a top surface of the cover and an engagement portion extending therefrom structured and arranged to be received in an engagement hole on the top of the clamping lever.
18. The link clamp quick change clamping assembly of Claim 17, wherein the engagement portion of the hand-actuated quick change lock pin comprises two circumferentially spaced radially moveable locking balls structured and arranged to engage a locking recess of the engagement hole of the clamping lever.
19. The link clamp quick change clamping assembly of Claim 18, wherein the hand-actuated quick change lock pin comprises a spring biased thumb plunger in a central longitudinal bore, the spring biased thumb plunger comprising a larger diameter plunger bulb and a smaller diameter central portion, wherein the spring biased plunger is axially moveable in the central longitudinal bore.
20. The link clamp quick change clamping assembly of Claim 19, wherein the larger diameter plunger bulb urges the two radially moveable locking balls radially outward when the larger diameter plunger bulb is in radial alignment with the two radially moveable locking balls, and the smaller diameter central portion retracts the two radially moveable locking balls radially inward when the smaller diameter central portion is in radial alignment with the two radially moveable locking balls.
, Description:FIELD OF THE INVENTION
[0001] The present invention relates to link clamp assemblies, and more particularly relates to quick change link clamp assemblies.
BACKGROUND INFORMATION
[0002] Link clamp assemblies are utilized to hold and clamp work pieces to fixtures so that the work pieces may be worked upon, e.g., machined, milled, turned, drilled and the like. Link clamp assemblies typically include a housing adapted for attachment to a fixture, a piston telescopically received within the housing for movement between a clamped position and a released position when hydraulic fluid is supplied to the housing, and a clamping lever or head attached to the distal end of the piston for holding and clamping the work piece to the fixture when the piston is shifted to its clamped position.
[0003] Based upon the requirements of different clamping applications, the clamping lever may be changed. In conventional link clamp assemblies, changing the clamping lever may require the removal of multiple pins and screws with the use of tools. The time-consuming process of changing the clamping lever leads to significant operational down time.
SUMMARY OF THE INVENTION
[0004] Link clamp assemblies are provided that include quick change clamping assemblies. The link clamp assemblies may be used for holding a part on a fixture. The quick change clamping assemblies include a hand-actuated lock pin mechanism. In certain embodiments, the hand-actuated lock pin mechanism may include a spring biased thumb plunger and radially moveable locking balls. The hand-actuated ball lock pin mechanism allows a cover, used to fix pins of the link clamp assembly, to be releasingly secured to the clamping lever. The ability to remove the cover from the clamping lever without tools allows for clamping levers to be changed quickly and effortlessly.
[0005] An aspect of the present invention is to provide a link clamp assembly for holding a workpiece comprising a housing with a bore defining a longitudinal axis, a piston received in the bore and moveable between retracted and extended positions along the longitudinal axis, a clamping lever pivotally connected to one end of the piston, the clamping lever structured and arranged to rotate relative to the housing in a single plane substantially parallel with the longitudinal axis of the bore, first and second link plates pivotally connected to the clamping lever structured and arranged to move the clamping lever to a clamped position when the piston is moved to the extended position, to move the clamping lever to a released position when the piston is moved to the retracted position, and a hand-actuated quick change clamping assembly releasably secured to the clamping lever structured and arranged to releasably secure the clamping lever to the piston and the first and second link plates.
[0006] Another aspect of the present invention is to provide a link clamp quick change clamping assembly comprising a clamping lever pivotally connected to a piston of a link clamp base, a link assembly pin structured and arranged to couple the clamping lever to first and second link plates of the link clamp base, a piston pin structured and arranged to couple the clamping lever to the piston of the link clamp base, a cover releasingly engageable to the top of the clamping lever comprising first and second front interior sidewall portions receiving the link assembly pin, the first and second link plates and the clamping lever therebetween, and first and second rear interior sidewall portions receiving the piston pin, the piston and the clamping lever therebetween, and a hand-actuated quick change lock pin structured and arranged to secure the cover to the top of the clamping lever.
[0007] These and other aspects of the present invention will be more apparent from the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a front isometric view of a link clamp assembly in a disengaged position in accordance with an embodiment of the present invention.
[0009] FIG. 2 is a rear isometric view of the link clamp assembly of FIG. 1.
[0010] FIG. 3 is a side view of the link clamp assembly of FIG. 1.
[0011] FIG. 4 is a rear isometric view of a link clamp assembly in an engaged position in accordance with an embodiment of the present invention.
[0012] FIG. 5 is a side view of the link clamp assembly of FIG. 4.
[0013] FIG. 6 is a rear view of the link clamp assembly of FIG. 4.
[0014] FIG. 7 is a top view of the link clamp assembly of FIG. 4.
[0015] FIG. 8 is a side-sectional view of the link clamp assembly taken through line 8-8 of FIG. 7 showing details of a quick change lock pin in accordance with an embodiment of the present invention.
[0016] FIG. 9 is a magnified view of a portion of FIG. 8.
[0017] FIG. 10 is an exploded rear isometric view of a link clamp assembly in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION
[0018] FIG. 1 illustrates a link clamp assembly 5 comprising a base assembly 10, a link assembly 40 and quick change clamping assembly 50 in accordance with an embodiment of the present invention. As shown in FIG. 4, the base assembly 10 comprises a housing 12 and a piston 14 received within a cylinder opening 16 and extendable from the housing 12 between retracted and extended positions along a longitudinal axis A. As shown in FIG. 8, the piston 16 is received in a piston chamber 18. In accordance with an embodiment of the present invention, the link assembly 40 may be coupled with the quick change clamping assembly 50 for shifting the quick change clamping assembly 50 between engaged and disengaged positions. As shown in FIG. 3, the quick change clamping assembly 50 comprises a clamping lever 52, a clamping lever cover 54, a hand-actuated quick change lock pin 80, a link assembly pin 75 and a piston pin 76. As used herein, the term “hand-actuated” means that the locking mechanism of the quick change lock pin does not require the use of any hand operated or power operated tools.
[0019] As shown in FIGS. 1-6 and 8 and 10, the housing 12 may include a cylindrical lower section 20 and an upper mounting flange section 22. However, any other suitable size or shape of housing may be used. In accordance with an embodiment of the present invention, the lower section 20 of the housing may be received within an opening in a fixture (not shown) and the upper mounting flange 22 may be attached to a top surface (not shown) of the fixture with bolts or other fasteners extending through the bolt holes 24 in the mounting flange. In accordance with an embodiment of the present invention, the upper mounting flange section 22 may comprise a pair hydraulic ports 28 and 29 in flow communication with conventional hydraulic tubing (not shown) for supplying hydraulic fluid to and discharging hydraulic fluid from link clamp assembly 5. As shown in FIG. 2, the hydraulic port 28 may be an inlet port and the hydraulic port 29 is an outlet port.
[0020] In accordance with an embodiment of the present invention, the piston 14 is inserted into the housing 12 of the base assembly 10 to be moveable in a vertical direction to provide the retracted and extended positions. In accordance with an embodiment of the present invention, the piston 14 may be moved between retracted and extended positions by methods that are known to those skilled in the art. For example, the piston 14 may move between retracted and extended positions when hydraulic fluid is delivered to the piston chamber 18 through the inlet hydraulic port 28 or discharged from the piston chamber 18 through the outlet hydraulic port 29. As shown in FIG. 8, the hydraulic fluid may be delivered and discharged from the hydraulic ports 28 and 29 to the piston chamber 18 by internal fluid passages. In certain embodiments, a first internal fluid passage 27 may be provided to an upper portion of the piston chamber 18, and a second internal fluid passage (not shown) may be provided to a lower portion of the piston chamber 18. In certain embodiments, when the piston 14 is in a retracted position a greater axial length is contained within the piston chamber 18.
[0021] As shown in FIGS. 1 and 2, the link assembly 40 is coupled with the quick change clamping assembly 50 for shifting the clamping assembly between its engaged and disengaged positions. In accordance with an embodiment of the present invention, the link assembly 40 includes first and second side link plates 42 and 44 each having a lower end pivotally connected to a mounting flange 46 on the upper mounting flange 22 of the housing 12 by a pin or shaft 48 and an upper end pivotally connected to the quick change clamping assembly 50 by the lever pin 75. In accordance with an embodiment of the present invention, the pin 48 may be secured in the mounting flange 46 by C-clips 49. However, any other suitable arrangement for securing the pin 48 in the mounting flange may be used. The link assembly 40 may move the clamping lever 52 to its engaged position when the piston 14 is extended as shown in FIGS. 4-6, and may shift the clamping lever 52 to its disengaged position when the piston 14 is retracted as shown in FIGS. 1-3. When the clamping lever 52 is in its raised position disengaged position as shown in FIGS. 3 and 10, the piston 14 is in a retracted position within the cylinder 16. When the clamping lever 52 is in its lowered engaged position as shown in FIGS. 4-8, the piston 14 has moved along the longitudinal axis A to an extended position in which the piston 14 is extended from the cylinder 16.
[0022] In accordance with an embodiment of the present invention, the quick change clamping assembly 50 allows the clamping lever 52 to be removably attached to the base assembly 10 and the link assembly 40. As shown in FIG. 3, the clamping lever 52 comprises a first clamping end 60 and a second piston end 62. In the embodiment shown, the clamping lever 52 is substantially rectangular. However, any other suitable shape may be used, e.g., L-shaped, S-shaped, curved or the like. A clamping lever having a different shaped may be used to allow for an offset between the first clamping 60 and the second piston end 62. In accordance with an embodiment of the present invention, the clamping lever 52 comprises a link assembly through hole 66 and a piston through hole 68. As shown in FIGS. 3 and 10, the piston through hole 68 extends through clamping lever 52 adjacent to the second end 62 and the link assembly through hole 66 extends through the clamping lever 52 between the piston through hole 68 and the clamping end 60. In the embodiment shown, the link assembly through hole 66 is provided between the midpoint of the clamping lever 52 and the second end 62. However, any other suitable location that allows the clamping lever 52 to pivot may be used. In accordance with an embodiment of the present invention, the second end 62 of the clamping lever 52 may include a piston notch 63 structured and arranged to receive piston 14. The piston notch 63 allows for a head of the piston 14 to be received within the clamping lever 52. The head of the piston 14 being received in the piston notch 63 allows for a rod or pin 76 to be inserted through the piston through hole 68 of the clamping lever 52 and the piston 14.
[0023] In accordance with an embodiment of the present invention, the clamping end 60 of the clamping lever 52 may comprise a contact portion 64 structured and arranged to engage a work piece (not shown). In accordance with an embodiment of the present invention, the clamping end 60 of the clamping lever 52 may include a threaded hole 70 for receiving the contact portion 64. However, any suitable type of engagement between the contact portion 64 and the clamping lever 52 may be used, e.g., integrally forming the contact portion and the clamping lever, welding, adhesives, press-fit, or the like.
[0024] In accordance with an embodiment of the present invention, the link assembly through hole 66 may be structured and arranged to receive the link assembly pin 75 and the piston through hole 68 may be structured and arranged to receive the piston pin 76. In the embodiment shown, the link assembly through hole 66 and link assembly pin 75 have diameters that are greater than the diameters of the piston through hole 68 and the piston pin 76. However, any other suitable arrangement may be used, e.g., the diameters of the link assembly through hole 66 and link assembly pin 75 may be less than or substantially equal to the size piston through hole 68 and the piston pin 76.
[0025] As shown in FIGS. 8-10, the clamping lever 52 comprises a pin hole 72 structured and arranged to receive the engagement shaft 90 of the quick change lock pin 80. In accordance with an embodiment of the present invention, the pin engagement hole 72 comprises a locking recess 74 sized to receive the radially moveable locking balls 92 of the quick change lock pin 80. In the embodiment shown, the locking recess 74 is formed as a cylindrical radial groove in the pin hole 72. However, any other suitable arrangement of engagement portion may be used, e.g., a radially extending rectangular recess formed in the pin engagement hole, a serrated portion or the like. In accordance with an embodiment of the present invention, the pin hole 72 and the locking recess 74 are formed without threading. The pin hole 72 and the locking recess 74 being free of threading allows for the hand-actuated quick change lock pin 80 to be released from the clamping lever without the use of a tool.
[0026] In accordance with an embodiment of the present invention, the hand-actuated quick change lock pin 80 may secure the clamping lever cover 54 onto the clamping lever 52. The clamping lever cover 54 may be structured and arranged to secure the link assembly pin 75 in the link assembly through hole 66 and the piston pin 76 in the piston through hole 68. As shown in FIG. 5, the clamping lever cover 54 may cover only a portion of the link assembly pin 75 and the piston pin 76 when they are secured in the clamping lever 52. As shown in FIGS. 6 and 10, the clamping lever cover 54 may be generally L-shaped and comprises first and second front interior sidewall portions 56 and 57, and first and second rear interior sidewall portions 58 and 59. In accordance with an embodiment of the present invention, the first and second front interior sidewall portions 56 and 57 are structured and arranged to contact the link assembly pin 75 to secure the pin 75 in the link assembly through hole 66. In accordance with an embodiment of the present invention, the link assembly 40 is coupled with the quick change clamping assembly 50 by the link assembly pin 75 passing through the first and second side link plates 42 and 44 and the clamping lever 52. The first and second front interior sidewall portions 56 and 57 are structured and arranged to receive the first and second side link plates 42 and 44 and the clamping lever 52 therebetween. In accordance with an embodiment of the present invention, the first and second rear interior sidewall portions 58 and 59 are structured and arranged to contact the piston pin 76 to secure the pin 76 in the piston through hole 68. In accordance with an embodiment of the present invention, the first and second rear interior sidewall portions 58 and 59 are closer together than the first and second front interior sidewall portions 56 and 57. The first and second rear interior sidewall portions receive the piston 14 therebetween. As shown in FIGS. 8-10, the top surface 53 of the clamping lever cover 54 comprises a through hole 55 structured and arranged to allow the engagement portion 90 of the quick change lock pin 80 to pass through the clamping lever cover 54.
[0027] As shown in FIGS. 8 and 9, the hand-actuated quick change lock pin 80 includes a top end 82, a cover abutment face 84 and an engagement portion 90 extending from the cover abutment face 84. As shown, the quick change lock pin 80 comprises a central longitudinal bore 81 extending from an opening 85 at the top end 82 to the engagement portion 90. In the embodiment shown, the top end 82 comprises radially extending finger tabs 83. In the embodiment shown, there are three radially extending tabs, but any other suitable number of tabs may be used, e.g., one, two, four or more tabs. In accordance with embodiments of the present invention, the radially extending tabs 83 allow for the quick change lock pin 80 to be easily grasped by a user. In accordance with an embodiment of the present invention, the central longitudinal bore 81 of the quick change lock pin 80 is structured and arranged to receive a hand-actuated spring biased thumb plunger 86. In certain, the central longitudinal bore 81 comprises a larger diameter portion adjacent to the opening 85 structured and arranged to contain a spring 95. As shown in FIGS. 8 and 9, the larger diameter portion of the central longitudinal bore 81 may transition to smaller diameter portion to form a shelf for seating the spring 95. However, any other suitable arrangement for mounting the spring 95 in the central longitudinal bore 81 may be used, e.g., protrusions or the like. In certain embodiments, the spring biased thumb plunger 86 comprises a smaller diameter central plunger portion 87 and a larger diameter plunger bulb 88. The spring biased thumb plunger 86 is axially moveable within the central longitudinal bore 81.
[0028] In accordance with an embodiment of the present invention, the cover abutment face 84 of the quick change lock pin 80 may engage the top surface 53 of the clamping lever cover 54. In certain embodiments, the engagement portion 90 is structured and arranged to pass through the through hole 55 of the clamping lever cover 54 and engage with the pin hole 72 of the clamping lever 52. The engagement portion 90 engages or fits within the pin hole 72 of the clamping lever 52 to secure the clamping lever cover 54 on the clamping lever 52. However, any other suitable type of fit between the engagement portion 90 and the pin hole 72 may be used, such as, a slide fit, a press fit, or the like. In accordance with an embodiment of the present invention, the shape of the engagement portion 90 is selected to correspond to the shape of the pin hole 72. In the embodiment shown, the engagement portion 90 and the pin hole 72 are substantially cylindrical, however, any other suitable shape of bore may be used, e.g., rectangular, square, triangular, ovular, hexagonal, D-shaped or the like.
[0029] In accordance with an embodiment of the present invention, the engagement portion 90 comprises at least one locking ball retainer socket 92 and at least one radially moveable locking ball 94. In the embodiment shown, the engagement portion 90 comprises two locking ball retainer sockets 92 and two radially moveable locking balls 94. In the embodiment shown, the engagement portion 90 comprises two circumferentially spaced locking balls 94. However, any other suitable number of radially moveable locking balls may be used, e.g., one, three, four or more. The retainer sockets 92 are substantially normal to the longitudinal bore 81 and are structured and arranged to allow the locking balls 94 to be moveable between a radially outward operative position wherein a portion of the locking balls 94 extends radially beyond a surface of the engagement portion 90, and a release position that is radially inward of the operative position. In the operative position, the locking balls 94 are structured and arranged to be received in the locking recess 74 of the pin hole 72. In certain embodiments, the locking recess 74 is sized and arranged to engage with the locking balls 94 to prevent longitudinal axial movement of the quick change lock pin 80. For example, at least a portion of the locking balls 94 may contact a portion of the locking recess 74. In certain embodiments, substantially all of the surface of each locking ball 94 extending from the engagement portion 90 contacts the locking recess 74.
[0030] The spring biased thumb plunger 86 may be axially moved within the central longitudinal bore 81 to position the smaller diameter central portion 87 and the larger diameter plunger bulb 88 in radial alignment with the locking balls 94. In accordance with an embodiment of the present invention, the radially moveable locking balls 94 move along the same line in different directions when contacted by the spring biased thumb plunger 86. As shown in FIGS. 8 and 9, the spring 95 is in its extended position. In the extended position, the larger diameter plunger bulb 88 of the thumb plunger 86 is in radial alignment with the locking balls 94 and urges the locking balls 94 outward in the retainer sockets 92 and into the locking recess 74 of the pin hole 72. In certain embodiments, the thumb plunger 86 may be depressed to place the spring 95 in a compressed position. When the spring 95 is in a compressed position, the smaller diameter central portion 87 retracts the two radially moveable locking balls 94 radially inward into the engagement portion 90 when the smaller diameter central portion 87 is in radial alignment with the two radially moveable locking balls 94. Radially retracting the locking balls 94 allows for the engagement portion 90 to be inserted into the through hole 55 of the clamping lever cover 54 and the pin hole 72. In accordance with an embodiment of the present invention, when hand-actuated pressure is released from the thumb plunger 86, the axial movement of the plunger 86 positions the larger diameter plunger bulb 88 in radial alignment with the retainer sockets 92 and locking balls 94. The quick change lock pin 80 secures the clamping lever cover 54 on the clamping lever 52. In accordance with an embodiment of the present invention, the clamping lever cover 54 being engaged on the clamping lever 52 by the quick change lock pin 80 secures the link assembly pin 75 and the piston pin 76 in the first and second link plates 42 and 44, the piston 14 and clamping lever 52.
[0031] In accordance with an embodiment of the present invention, the radially outwardly biased locking balls 94 avoid the necessity of using a screw to secure the clamping lever cover 54 on the clamping lever 52. The hand-actuated quick change lock pin 80 allows for the clamping lever cover 54 to be quickly and effortlessly secured onto the clamping lever 52. When the locking balls 94 are engaged in the locking recess 74, the engagement between the cover abutment face 84 of the quick change lock pin 80 and the top surface 53 of the clamping lever cover 54 provides a rigid connection.
[0032] In accordance with an embodiment of the present invention, the clamping lever 52 may be installed in the link clamp assembly 5 according to the following procedure. The piston through hole 68 of the clamping lever 52 may be aligned with the head of the piston 14 and the piston pin 76 may be inserted through the piston through hole 68 and the piston 14 to pivotally connect the clamping lever 52 with the piston 14. The link assembly though hole 66 of the clamping lever 52 may be aligned with the first and second link plates 42 and 44 and the link pin 75 may be inserted through the link assembly through hole 68 and the first and second link plates 42 and 44 to pivotally connect the clamping lever 52 with the first and second link plates 42 and 44. The clamping lever cover 54 may be placed onto the clamping lever 52 with the through hole 55 aligned the pin hole 72 of the clamping lever 52. The first and second front interior portions 56, 57 of the clamping lever cover contact the ends of the link pin 75 and the first and second rear interior portions 58, 59 contract the ends of the piston pin 76. The engagement portion 90 of the quick change lock pin 80 may then be inserted into the through hole 55 and the pin hole 72. The locking balls 94 of the engagement portion 90 may then be engaged with the locking recess 74 of the pin hole 72 to secure the clamping lever cover 54 on the clamping lever 52. In accordance with an embodiment of the present invention, when the cover abutment face 84 contacts the top surface 53 of the clamping lever cover 54, the locking balls 94 of the engagement portion 90 may engage with the locking recess 74 of the pin hole 72.
[0033] In accordance with an embodiment of the present invention, the clamping lever 52 may be removed according to the following process. The spring biased thumb plunger 86 of the quick change lock pin 80 may be depressed to retract the radially moveable locking balls 94 from the locking recess 74 of the pin hole 72 of the clamping lever 52. The quick change lock pin 80 may be removed from the pin hole 72 and the through hole 55 of the clamping lever cover 54. The clamping lever cover 54 may then be removed from the clamping lever 52. Removing the clamping lever cover 54 allows for the link assembly pin 75 to be removed from the first and second link plates 42 and 44 and the clamping lever 52 and the piston pin 76 to be removed from the clamping lever 52 and the piston 14. The clamping lever 52 may then be removed from the link assembly 40 and the base assembly 10.
[0034] The base assembly 10, the link assembly 40 and the quick change clamping assembly 50 may be made of any suitable material, such as steel, aluminum, titanium or any other material having sufficient strength. The clamping lever, clamping lever cover and quick change lock pin of the present invention may be fabricated by any suitable technique.
[0035] As used herein, “including,” “containing” and like terms are understood in the context of this application to be synonymous with “comprising” and are therefore open-ended and do not exclude the presence of additional undescribed or unrecited elements, materials, phases or method steps. As used herein, “consisting of” is understood in the context of this application to exclude the presence of any unspecified element, material, phase or method step. As used herein, “consisting essentially of” is understood in the context of this application to include the specified elements, materials, phases, or method steps, where applicable, and to also include any unspecified elements, materials, phases, or method steps that do not materially affect the basic or novel characteristics of the invention.
[0036] For purposes of the description above, it is to be understood that the invention may assume various alternative variations and step sequences except where expressly specified to the contrary. Moreover, all numbers expressing, for example, quantities of ingredients used in the specification and claims, are to be understood as being modified in all instances by the term “about”. Accordingly, unless indicated to the contrary, the numerical parameters set forth are approximations that may vary depending upon the desired properties to be obtained by the present invention. At the very least, and not as an attempt to limit the application of the doctrine of equivalents, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.
[0037] It should be understood that any numerical range recited herein is intended to include all sub-ranges subsumed therein. For example, a range of “1 to 10” is intended to include all sub-ranges between (and including) the recited minimum value of 1 and the recited maximum value of 10, that is, having a minimum value equal to or greater than 1 and a maximum value of equal to or less than 10.
[0038] In this application, the use of the singular includes the plural and plural encompasses singular, unless specifically stated otherwise. In addition, in this application, the use of “or” means “and/or” unless specifically stated otherwise, even though “and/or” may be explicitly used in certain instances. In this application, the articles “a,” “an,” and “the” include plural referents unless expressly and unequivocally limited to one referent.
[0039] Whereas particular embodiments of this invention have been described above for purposes of illustration, it will be evident to those skilled in the art that numerous variations of the details of the present invention may be made without departing from the invention as defined in the appended claims.