Abstract: A thermoformer apparatus has sheet supporting rails which are divided into sections hinged together to facilitate widening of the spacing between the rails with adjuster drive mechanism as the sheet moves through an oven to eliminate sagging of the sheet as it becomes heated. Thermoformer chains are driven by a pair of independently operable servo motors each associated with a respective thermoformer chain.

Abstract: A plug assist drive assembly for driving plug assists in a thermoforming apparatus includes a single centrally located roller screw assembly enclosed in a housing and driving a third platen mounting the plug assist with a group of guide-drive bars connected to a drive platen which is driven by the roller screw nut. The roller screw assembly is removable by removing screws holding the nut to one hub adapter, the screws accessed through an opening in the housing normally covered with a plate.

Abstract: A method and apparatus for thermoforming deep drawn parts such as cups in which a vacuum is momentarily applied to a preheated sheet material when overlying a clamping plate prior to clamping and advance of the plug assists to delay contact with a lip molding feature projecting from each mold cavity. This avoids a molding defect due to premature cooling of a localized region of the sheet material when the sheet material comes into contact with the lip molding features.

Abstract: A forming station for a thermoformer in which the lower platen is lowered and moved laterally on linear bearings on the machine frame after two sheets are formed in side by side mold-plug assist tool sets so as to align the respective molds and formed sheets. The formed sheets are squeezed together with flanges on the formed sheets thereby fused together by a draw mechanism including a series of hydraulic cylinders which are connected to coupled elements carried by the upper and lower platens so as create the squeezing movement when the cylinders are pressurized. A precision control is exercised over the operation of each of the cylinders using a position sensing device associated with each cylinder to insure equal movement of the output member of each cylinder. The lower platen vertical drive is activated in correspondence with the travel produced by the hydraulic cylinders to reduce the load on a brake holding the upper platen stationary.

Abstract: A quick change mounting for each plug assist in an array of plug assists, carried by a base plate in a thermoformer apparatus includes a boss projecting from an anchor piece attached to the base plate and a base piece attached to each plug assist, each base having a bore slidably receiving a boss. Each boss has a cross pin with projecting ends each which being received in respective axial slot in the associated base piece, a circumferential clearance space extending from the end of each axial slot allowing rotation of the plug assist, the pin ends each releasably held at the end of a circumferential space by a detent.

Abstract: A thermoforming apparatus for forming sheets of sheet plastic onto a substrate in which a retractable substrate heater is able to be positioned over a substrate loaded into the press and energized while a plastic sheet is being heated in an oven included in the thermoformer apparatus. The plastic sheets are cut from a strip pulled from a roll of sheet material, the roll supported for side to side movement and driven by a servomotor responsive to error signals generated by a strip edge sensor to compensate for wandering of a strip edge to thereby insure accurate location of plastic sheets cut from the unwound strip.

Abstract: A plug assist tooling assembly for a roll fed, post trim thermoforming machine in which a spider plate connecting plug assist rods is located below one or more support plates holding a clamping plate having an array of holes formed therein each defining a chamber each receiving a plug assist which chambers are sealed when sheet material is clamped by rings encircling the open top of each chamber to enable air pressure communicating to each chamber to exert forming pressure on the section of sheet material within each clamping ring. The support plates are fixed spaced from one of the main platens by standoffs fixed relative to the support plate or plates and the platen, the spider plate located in the same space.

Abstract: A thermoforming machine utilizes two clamping frames to advance cut sheets through heating and forming stations, with the clamping frames returned via an overhead path above the oven in the heating station. Pneumatic cylinders arranged about the inner perimeter of the frames are operated to grip the sheet and release the sheets, which are pressurized and released via fluid connections established when the frames are lifted from a transfer bar structure at the loading and forming stations. The clamping frames have pivoted end sections which are engaged by extendible gear posts at the forming station to bend the clamped sheet into greater conformity with the tooling shape prior to forming.

Abstract: A method of driving part ejector pins at a high cycle rate by a reversible servo motor rotating a crank unidirectionally to advance a pin mounting structure from a retracted position to an advanced eject position, and back to the retracted position, and reversing the motor to repeat the cycle with only a single motor reversal.

Abstract: Adjustable clamping frames for rotary thermoforming machine have movable sets of clamp supporting members which are driven by selectively engageable drive units to carry out a size adjustment at a station in the thermoforming machine.

Abstract: A twin sheet thermoforming method and apparatus of a type using a rotary wheel to carry each of a series of clamping frames for releasably holding sheets to be formed through successive processing stations. The clamping frames can be shuttled on the wheel to be alternatively located for alignment with one of two forming tooling sets at a forming station, and to be shiftable at an unload-load station so that unloading and loading do not occur at the same location.

Abstract: A thermoformer apparatus having a press driving upper and lower platens by respective pairs of servo motors, each pair driving four toggle linkages to stabilize the platen against the forming pressures. Linear bearings are provided on four corner posts for precision guiding of the platen motion.

Abstract: A curling screw adjustment mechanism for changing the radial spacing of the curling screws of a lip curling machine forming a lip on a thermoformed plastic container such as a cup, in which the curling screws are each mounted on separate interlinked pivoted mounting plates which are moved in unison by adjustments of a threaded rod. The curling screws are also cooled by indirect contact with a cooling liquid circulated through separate aluminum arbors on which the stainless steel curling screws are mounted to allow changing the curling screws without spillage of coolant.

Abstract: A lip rolling machine for thermoformed containers in which the rim heating oven is mounted to be swingable out of its operative position for ready access to the machine components for servicing or set up. The oven is also readily detachable to be removed for convenient servicing of the oven. Guide rod adjustment mechanisms are provided for each end of the guide rods allowing the guide rod spacing at each end to be adjusted by radial in unison movement of the ends by a series of pivoting interlinked arms moved by a handle integral with one arm in each series. A stop arrangement including a threaded rod, and Bridgeport clamps positively secures each handle in an adjusted position. An adjustable transition conveyor is provided at the entrance of the machine with one end raisable by pivoting about a drive pulley axis at the other end to accommodate different sizes of containers.

Abstract: A thermoforming press in which the shut height of upper and lower platens is adjustable by a keyed connection between a press frame top assembly and each of four posts of the frame established by pieces which are movable and which also act as cams to raise or lower the frame top assembly, moving the upper platen therewith to vary the shut height. The movable pieces are moved in unison by a drive motor to insure uniform movement of the frame top assembly. The platens are driven by rotary crank plates, which are in turn driven by rotary output shafts of right angle drives. Pairs of rollers engage the perimeter of each crank plate on one side to resist bending loads on each shaft.

Abstract: A thermoforming machine utilizes two clamping frames to advance cut sheets through heating and forming stations, with the clamping frames returned via an overhead path above the oven in the heating station. Pneumatic cylinders arranged about the inner perimeter of the frames are operated to grip the sheet and release the sheets, which are pressurized and released via fluid connections established when the frames are lifted from a transfer bar structure at the loading and forming stations. The clamping frames have pivoted end sections which are engaged by extendible gear posts at the forming station to bend the clamped sheet into greater conformity with the tooling shape prior to forming.

Abstract: A wheeled tooling cart for a thermoformer machine enabling quick and easy removal and installation of upper and lower tooling plates from their respective platens. The tooling plates are held on upper framework on the cart, which are removed one at a time with the cart in position adjacent the machine with one and the opposite end successively. The tooling plates are held in position on the cart for reinstallation when the cart is appropriately repositioned with respect to the thermoformer machine. An elevator mechanism allows an upper framework having attachment brackets and rails for holding the tooling plates to be raised and lowered on a wheeled lower framework to move the attachment brackets and rails into proper position for attachment and removal of the tooling plates.