Workpiece clamping and positioning apparatus

Clamping device for quickly and accurately positioning and maintaining a pair of workpieces in predetermined, generally end-to-end angularly related positions and being characterized by evenly and resiliently applying clamping forces and positioning forces to the pair of workpieces regardless of slight variations in width of the workpieces, said clamping device comprising

• backstop means having respective angularly related surface portions positioned for receiving the respective outside longitudinal side edges of the workpieces and for potitioning the workpieces in predetermined angularly related positions with respect to one another defining a predetermined included angle therebetween,
• slide block means mounted for longitudinal movement toward and away from the workpieces and said backstop means along an axis bisecting the included angle formed by the workpieces when positioned against said backstop means, said slide block means having a solid medial portion and transversely spaced-apart voids therein on each side of the solid medial portion,
• a pair of gripper members positioned respectively within the transversely spaced-apart voids of said slide block means, said gripper members each having portions thereof extending outwardly beyond said slide block means and facing toward said backstop means and defining respective workpiece engaging surfaces,
• means operatively connecting said pair of gripper members to said slide block means for simultaneous longitudinal movement with said slide block means for engaging the inside longitudinal edges of the respective workpieces and for clamping the workpieces against said backstop means, and said means operatively connecting said pair of gripper members to said slide block means also allowing independent generally transverse movement of the gripper members relative to one another so that upon engagement of the gripper members with the respective inside edges of the workpieces, the gripper members may move transversely toward one another for sliding the workpieces toward each other for a tight end-to-end abutment,
• said means operatively connecting said pair of gripper members to said slide block means comprising respective pin means secured to each of said gripper members and extending therefrom, and respective generally rounded slot means formed in said slide block means and being of greater dimensions than said pin means and respectively receiving the pin means therein,
• resilient elastomeric members positioned between opposing surfaces of said gripper members and the solid medial portion of said slide block means and cooperating with said gripper members for biasing the same away from the medial portion of said slide block means in opposition to transverse movement for the gripper members toward one another for thereby insuring substantially equal and even application of the clamping and positioning forces by said gripper members to the respective workpieces regardless of slight variations in width thereof.
• means operatively connected with said slide block means for moving the same and said gripper members into and out of clamping engagement with the workpieces, and
• means operatively connected with said slide block member for releasably locking the same and said gripper members in clamping engagement with the workpieces.

Clamping apparatus for quickly and accurately positioning and maintaining a pair of mitered end picture frame moldings in desired end-to-end angularly related positions for being fastened together to form picture frames and being characterized by evenly and resiliently applying clamping forces and positioning forces to the pair of picture frame moldings regardless of slight variations in width of the moldings, said apparatus comprising

• work table means for receiving the bottom surfaces of the mitered end picture frame moldings to be secured together in end-to-end angularly related relationship,
• backstop means carried by said work table means and having respective angularly related surface portions positioned for receiving the outside longitudinal side edge of each of the picture frame moldings and for positioning the picture frame moldings in predetermined angularly related positions with respect to one another defining a predetermined included angle therebetween,
• slide block means mounted on said work table means within the included angle formed by the picture frame moldings when positioned against said backstop means and positioned for movement along a longitudinal axis bisecting the included angle and toward and away from the inside longitudinal side edges of the moldings,
• a pair of gripper means operatively connected to and carried by said slide block means in side-by-side transversely spaced relation to one another and extending forwardly of said slide block means facing toward said backstop means and defining respective workpiece engaging surfaces,
• said pair of gripper means being operatively connected to said slide block means for simultaneous movement with the slide block means longitudinally toward the picture frame moldings and said backstop means for engaging the inside longitudinal edges of the respective moldings and for clamping the moldings against said backstop means, and said pair of gripper means also being operatively connected to said slide block means for allowing independent, generally transverse movement relative to one another, so that upon engagement of the gripper means with the respective inside edges of the moldings the gripper means may move transversely toward one another for sliding the moldings toward each other for a tight end-to-end abutment, and
• resilient means cooperating with each of said gripper means for biasing and cushioning the gripper means in opposition to transverse movement of the gripper means toward one another for thereby insuring substantially equal and even application of the clamping and positioning forces by said gripper means to the respective workpieces regardless of slight variations in width thereof.