Servo-clamping device

• US 4,732,373 A
• Filed: 06/12/1985
• Issued: 03/22/1988
• Est. Priority Date: 12/22/1983
• Status: Expired due to Term

• Current Assignee: Tai-Her Yang
• Original Assignee: Tai-Her Yang
• Inventors: Yang, Tai-Her
• Primary Examiner(s): Watson, Robert C.
• Application Number:
  US06/743,981
• Time in Patent Office: 1,014 Days
• Field of Search: 269/257-259, 269/261-262, 269/265, 269/268, 269/242, 269/241
• US Class Current: 269/241
• CPC Class Codes: B25B 1/20 Vices for clamping work of special profile, e.g. pipes
• CPC Class Codes: B25B 1/2426 the parts having a pivotal movement
• CPC Class Codes: B25B 1/2452 with supplementary jaws

Abstract

A clamping apparatus includes two pairs of rotatable and substantially cylindrical clamping elements positioned on jaws of the clamping apparatus. One pair of clamping elements is located on a fixed jaw, and the second pair is located on a movable vise jaw. The jaws are supported on a generally rectangular base which has a pair of end portions. One end portion is a first upstanding flange formed integrally with the base. The second end portion is the fixed jaw. A two-way threaded rod is carried by the movable vise jaw and one threaded end extends through a cooperating threaded recess in the first upstanding flange. The movable vise jaw has a transverse notch located in its bottom to receive a hollow cylindrical nut which is internally threaded in a first direction. Adjacent to the cylindrical nut is a friction ring. The second threaded end of the threaded rod, threaded in the second direction, is threaded into the cylindrical nut. There are two speeds for moving the movable vise member towards the fixed member. One speed of movement occurs when the clamping members are not in engagement with the workpiece. The second speed of movement occurs when the clamping members are engaging the workpiece.

Claims

1. A clamping apparatus, comprising:

a pair of vise jaws supported on a common base, at least one of said vise jaws being movable and at least one of which being fixed, each of the vise jaws having a pair of concave recesses formed therein laterally of each other,

a clamping member in each of the recesses and having a convex surface substantially complementary to the respective concave recesses, the concave recesses and convex surfaces being formed about a vertical axis, wherein, in a cross-sectional plane substantially at right angles to the respective axes, each axis forms the center of a circle substantially defining the respective concave recesses and convex surfaces,

means for supporting each clamping member for pivotable movement about its respective vertical axis, and each of the clamping members having a plurality of substantially-flat chordal faces intersecting one another and disposed oppositely of the convex surface on the respective clamping member, the chordal faces on one pair of clamping members on a respective vise jaw confronting the chordal faces on the other pair of clamping members on the other respective vise jaw, thereby engaging and securely retaining a workpiece between the respective vise jaws,

threaded rod means for moving said vise jaws towards and away from one another, said threaded rod means having a first portion threaded in a first direction and a second portion threaded in a second direction,

internally threaded nut means threaded in a first direction, said nut means receiving said first portion of said threaded rod means,

either said movable jaw or said fixed jaw having internal threads threaded in a second direction for receiving said second portion of said threaded rod means and for advancing said threaded rod means through said jaw,

resilient friction ring means in frictional contact with said internally threaded nut means, said friction ring means for permitting said first portion of said threaded rod means to rotate within and advance through said internally threaded nut means when said movable jaw advances toward said fixed jaw prior to contacting the workpiece, and said friction ring means for permitting said first portion of said threaded rod means to cause said nut means to rotate with said threaded rod means when said movable jaw is in contact with the workpiece.

2. A servo-clamping device, comprising:

a generally rectangular base having a pair of end portions,

a first upstanding flange formed integrally with the base at one end portion thereof,

a second upstanding flange formed integrally with the base at the other end thereof and constituting a fixed vise jaw, the base having a slideway formed therein substantially longitudinally thereof,

a movable vise jaw slidably received within the slideway,

threaded rod means for moving said vise jaws towards and away from one another, said threaded rod means having a first portion threaded in a first direction and a second portion threaded in a second direction, said threaded rod carried by the movable vise jaw and extending through a cooperating threaded recess in the first upstanding flange at the one end portion of the base, the second upstanding flange at the other end of the base having a first pair of spaced-apart concavely-formed vertically-extending seats, the movable vise jaw having a second pair of spaced-apart concavely-formed vertically-extending seats substantially opposite to the respective seats in the first pair of seats in the fixed vise jaw,

internally threaded nut means threaded in a first direction, said nut means receiving said first portion of said threaded rod means,

either said movable jaw or said fixed jaw having internal threads threaded in a second direction for receiving said second portion of said threaded rod means and for advancing said threaded rod means through said jaw,

resilient friction ring means in frictional contact with said internally threaded nut means, said friction ring means for permitting said first portion of said threaded rod means to rotate within and advance through said internally threaded nut means when said movable jaw advances toward said fixed jaw prior to contacting the workpiece, and said friction ring means for permitting said first portion of said threaded rod means to cause said nut means to rotate with said threaded rod means when said movable jaw is in contact with the workpiece,

a substantially cylindrical upstanding clamping jaw received within each of the seats in each pair of seats, each clamping jaw having a convexly-formed surface complementary to its respective concavely-formed seat,

means for pivotably mounting each clamping jaw on the base for independent pivotal movement, and each clamping jaw having at least one pair of vertically-truncated adjacent flat surfaces for clamping against a workpiece inserted between the jaws, wherein the jaws pivot independently and are adapted to clamp an irregularly-shaped workpiece.

3. A clamping apparatus for clamping a workpiece, said clamping apparatus comprising:

a pair of vise jaws supported on a common base, at least one of said vise jaws being movable and at least one of which being fixed,

threaded rod means for moving said vise jaws towards and away from one another, said threaded rod means having a first portion threaded in a first direction and a second portion threaded in a second direction, wherein one threaded portion of said threaded rod is in engagement with a stationary structure of said clamping apparatus and wherein the other threaded portion of said threaded rod is in engagement with a movable structure of said clamping apparatus,

internally threaded nut means threaded in a first direction, said nut means receiving said first portion of said threaded rod means,

either said movable jaw or said fixed jaw having internal threads threaded in a second direction for receiving said second portion of said threaded rod means and for advancing said threaded rod means through said jaw,

resilient friction ring means in frictional contact with said internally threaded nut means, said friction ring means for permitting said first portion of said threaded rod means to rotate within and advance through said internally threaded nut means when said movable jaw advances toward said fixed jaw prior to contacting the workpiece, and said friction ring means for permitting said first portion of said threaded rod means to cause said nut means to rotate with said threaded rod means when said movable jaw is in contact with the workpiece.

4. The clamping apparatus described in claim 3 wherein said internally threaded nut means and said friction ring means are located in a notch on said movable vise jaw.

5. The clamping apparatus described in claim 3 wherein said internally threaded nut means and said friction ring means are located in an aperture on a stationary upstanding flange portion of said base.