Clamping frame for plastic sheet material

Claim 2

Apparatus for supporting plastic sheet material during thermoforming thereof, comprising; a framework shaped to surround a sheet of plastic material, support means mounted on said framework for movement from a retracted position outwardly spaced from the peripheral edges of said sheet of plastic material to a position adapted to engage and support one surface of a sheet of plastic material, holding means mounted on said framework for movement from a retracted position outwardly spaced from the peripheral edges of said sheet of plastic material to a position adapted to engage and hold the opposite surface of said sheet of plastic material, said support and holding means being movable independently of each other from one position to the other, means to simultaneously actuate said support means to sheet engaging and retracted positions, and means to simultaneously actuate said holding means to sheet engaging and retracted positions.

Claim 3

The apparatus set forth in claim 1 in which said framework includes pairs of parallel spaced side and end members, each of said members being adjustable to selected positions toward and away from the edge of said plastic sheet material for different lengths and widths of plastic sheets and in a plane generally parallel thereto independently of the other of said members, and in which said support and holding means are mounted on said members.

Claim 4

The apparatus set forth in claim 2 in which said support means include a plurality of support arms substantially uniformly spaced longitudinally of each of said members and in which said holding means include a plurality of holding arms substantially uniformly spaced longitudinally of each of said members.

Claim 5

The apparatus set forth in claim 3 and further comprising first connecting means associated with each of said members and connecting said support arms associated with each of said members to each other for simultaneous movement in response to movement of at least one of said support arms, and second connecting means associated with each of said members and connecting said holding arms associated with each of said members to each other for simultaneous movement in response to movement of at least one of said holding arms, and first additional means connecting said first connecting means to each other for simultaneous movement of all of said support arms and second additional means connecting said second connecting means to each other for simultaneous movement of all of said holding arms.

Claim 6

The combination set forth in claim 4 in which the first and second connecting means are each toothed racks and in which the additional means connecting said first connecting means together And said second connecting means together are toothed gears in simultaneous engagement with a pair of said racks.

Claim 7

The combination set forth in claim 1 wherein said support means include a plurality of support arms substantially uniformly spaced apart around the perimeter of said framework and wherein said holding means include a plurality of holding arms substantially uniformly spaced around said framework, said support and holding arms being disposed for pivotal movement from said retracted positions to said positions engaging opposed surfaces of said plastic sheet material.

Claim 8

The combination set forth in claim 6 wherein said means to simultaneously actuate said support means and said holding means includes first connecting means connecting said support arms to each other for simultaneous pivotal movement of all of said support arms in response to pivotal movement of one of said support arms, and second connecting means connecting said holding arms to each other for simultaneous pivotal movement of all of said holding arms in response to pivotal movement of at least one of said holding arms.

Claim 9

The apparatus set forth in claim 7 and further comprising actuator means for moving at least one of said support arms and at least one of said holding arms.

Claim 10

The combination set forth in claim 7 in which said first and second connecting means are in the form of toothed racks and in which each of said arms are provided with toothed gear portions, in engagement with the teeth of said racks.

Claim 11

The combination set forth in claim 9 and further including first toothed gear means interconnecting said toothed racks associated with said support arms for simultaneous movement of said support arms in response to movement of one of said toothed racks, and second toothed gear means interconnecting said toothed racks associated with said holding arms for simultaneous movement of said holding arms in response to movement of one of said toothed racks.

Claim 12

The combination set forth in claim 10 and further comprising additional support arms formed integrally with said first toothed gear means, additional holding arms formed integrally with said second toothed gear means, and wherein movement of one of said racks associated with said support arms and movement of one of said racks associated with said holding arms is operative to move said arms through an arc of substantially 90* and said additional arms through an arc of 45* from a retracted position to a sheet engaging position.

Claim 13

The apparatus set forth in claim 7 and further comprising actuator means supported separately from said framework and operatively connected to each of said connecting means.

Claim 14

The apparatus set forth in claim 6 in which each of said support arms is disposed opposite a holding arm in opposed positions at opposite sides of said plastic sheet material when said arms are in engagement with the latter.

Claim 15

The combination set forth in claim 6 in which said arms are each mounted for pivotal movement about axes perpendicular to the plane of said sheet of plastic material.

Claim 16

The apparatus set forth in claim 6 and further comprising a roller mounted on each of said holding arms for rotation about an axis parallel to the plane of said sheet of plastic material and adapted to engage the latter.

Claim 17

Apparatus for supporting a pair of sheets of plastic material in parallel spaced relation to each other comprising: a frame means shaped to surround said sheets of plastic material, said frame means including pairs of parallel spaced side and end members, separate sets of support means mounted on said side and end members for movement between a retracted position outwardly spaced from the peripheral edges of said sheets of plastic material and a position adapted to engage and support one side of each sheet of plastic material, separate sets of holding means mounted on said side and end members for movement between a retracted position outwardly spaced from the peripheral edGes of said sheets of plastic material and a position adapted to engage and hold the other side of each sheet of plastic material, said separate sets of support and holding means being movable independently of each other between said positions, and means to move said separate sets of support means and said holding means between sheet engaging and retracted positions.

Claim 18

Apparatus for supporting a pair of sheets of plastic material in parallel spaced relation to each other comprising: a frame means shaped to surround said sheets of plastic material, said frame means including pairs of parallel spaced side and end members, separate sets of support means mounted on said side and end members for movement between a retracted position outwardly spaced from the peripheral edges of said sheets of plastic material and a position adapted to engage and support one side of each sheet of plastic material, separate sets of holding means mounted on said side and end members for movement between a retracted position outwardly spaced from the peripheral edGes of said sheets of plastic material and a position adapted to engage and hold the other side of each sheet of plastic material, said separate sets of support and holding means being movable independently of each other between said positions, and means to move said separate sets of support means and said holding means between sheet engaging and retracted positions.

Claim 19

The combination set forth in claim 16, each of said members being adjustable to selected positions toward and away from said plastic sheet material and in a plane parallel thereto independently of the other members.

Claim 20

The combination set forth in claim 16 wherein pairs of support means are associated with said pairs of sheets of plastic material, respectively, and wherein pairs of holding means are associated with said pairs of sheets of plastic material, respectively.

Claim 21

The combination set forth in claim 18 wherein each of said support means includes a plurality of support arms substantially uniformly spaced apart longitudinally of each of said members and wherein each of said holding means include a plurality of holding arms substantially uniformly spaced longitudinally of each of said members, said support arms and holding arms being disposed for pivotal movement from a retracted position to positions engaging opposed surfaces of said sheets of plastic material.

Claim 22

The combination set forth in claim 19 and further comprising connecting means connecting said support arms associated with a given sheet of plastic material to each other for simultaneous pivotal movement and connecting means connecting the holding arms associated with a given sheet of plastic material to each other for simultaneous pivotal movement.

Claim 23

The combination set forth in claim 19 and further comprising actuator means supported separately from said framework and operatively engaged with each of said connecting means.

Claim 24

Apparatus for supporting a pair of sheets of plastic material comprising, first frame means shaped to surround and adapted to be associated with one sheet of said pair of sheets of plastic material, second frame means shaped to surround and adapted to be associated with the other sheet of plastic material, first support means mounted on said first frame means for movement between a retracted position outwardly spaced from the peripheral edges of said one sheet of plastic material and a position adapted to engage and support one side of said one sheet of plastic material, holding means mounted on said first frame means for movement between a retracted position outwardly spaced from the peripheral edges of said one sheet of plastic material and a position adapted to engage and hold the other side of said one sheet of plastic material, second support means mounted on said second frame means for movement between a retracted position outwardly spaced from the peripheral edges of said other sheet of plastic material and a position adapted to engage and support one side of said other sheet of plastic material, and holding means mounted on said second frame means for movement between a retracted position outwardly spaced from the peripheral edges of said other sheet of plastic material and a position adapted to engage and hold the other side of said other sheet of plastic material, separate conveyor means operatively associated with each of said first and second frame means and supporting said frame means for movement in parallel spaced relationship to each other, and means detachably connecting said first and second frame means to each other for movement in unison and being detachable to permit movement on said separate conveyor means independently of each other.

Claim 25

Apparatus for supporting a pair of sheets of plastic material comprising, first frame means shaped to surround and adapted to be associated with one sheet of said pair of sheets of plastic material, second frame means shaped to surround and adapted to be associated with the other sheet of plastic material, first support means mounted on said first frame means for movement between a retracted position outwardly spaced from the peripheral edges of said one sheet of plastic material and a position adapted to engage and support one side of said one sheet of plastic material, holding means mounted on said first frame means for movement between a retracted position outwardly spaced from the peripheral edges of said one sheet of plastic material and a position adapted to engage and hold the other side of said one sheet of plastic material, second support means mounted on said second frame means for movement between a retracted position outwardly spaced from the peripheral edges of said other sheet of plastic material and a position adapted to engage and support one side of said other sheet of plastic material, and holding means mounted on said second frame means for movement between a retracted position outwardly spaced from the peripheral edges of said other sheet of plastic material and a position adapted to engage and hold the other side of said other sheet of plastic material, separate conveyor means operatively associated with each of said first and second frame means and supporting said frame means for movement in parallel spaced relationship to each other, and means detachably connecting said first and second frame means to each other for movement in unison and being detachable to permit movement on said separate conveyor means independently of each other.

Claim 26

The combination set forth in claim 22 in which said separate conveyor means are disposed to permit displacement of said first and second frame means in planes parallel to each other and varying in vertical spacing from each other.