Fiber chopper and method of chopping
AssigneeJohns Manville International, Inc.
InventorsRandall Bascom, Douglas Kempski, John Dembowski
Life of this patent
Estimating the term…
Abstract
A method and apparatus for chopping long unwound items like fiber, fiber strands, yarn, etc. The chopper has a backup roll, a blade roll and a biasing system for forcing the backup roll and the blade roll together at a desired force during set up and operation. The biasing system contains a mechanism such as a slip clutch or a limited torque stepping motor for maintaining a substantially constant biasing force at set up and during operation while allowing the rolls to separate slightly to pass a temporary thicker feed without recoil that currently shortens blade and backup roll working layer life.
Claims24
A chopper for separating long lengths of unwound item(s) selected from the group consisting of fibers, fiber strands, string, yarn, wire, tape and ribbon into short pieces comprising a frame, a rotatable backup roll outboard of one side of the frame, the backup roll having a peripheral working layer, a rotatable blade roll outboard of the side of the frame, the blade roll having a plurality of blades spaced apart around its periphery for contact with and penetration of said items and into the peripheral working layer and a biasing system for biasing the blades of the blade roll and the backup roll together, the improvement comprising;
- the biasing system being an assembly for biasing the blade roll and the backup roll together with a substantially constant force, said force being such that the blades of the blade roll will penetrate the backup roll only a desired distance, said biasing system comprising a mechanical jack that extends and retracts as an element of the mechanical jack is rotated one direction and the other direction respectively, a motor assembly for rotating said element, said motor assembly being able to maintain a substantially constant torque to the element of the mechanical jack during operation of the chopper.
(canceled)
(canceled)
A chopper for separating long lengths of unwound item(s) selected from the group consisting of fibers, fiber strands, string, yarn, wire, tape and ribbon into short pieces comprising a frame, a rotatable backup roll outboard of one side of the frame, the backup roll having a peripheral working layer, a rotatable blade roll outboard of the side of the frame, the blade roll having a plurality of blades spaced apart around its periphery for contact with and penetration of said items and into the peripheral working layer and a biasing system for biasing the blades of the blade roll and the backup roll together, the improvement comprising;
- the biasing system being an assembly for biasing the blade roll and the backup roll together with a substantially constant force, the assembly comprising a screw jack that extends and retracts as an element of the screw jack is rotated in one direction and then in the opposite direction respectively , a stepping motor for rotating the element a desired amount to cause the blades to penetrate the peripheral working layer a desired amount.
A method of separating long lengths of unwound item(s) selected from the group consisting of fibers, fiber strands, string, yarn, wire, tape and ribbon into short pieces comprising feeding one or more items in an unwound form into a chopper comprising a frame, a rotatable backup roll outboard of one side of the frame, the backup roll having a peripheral working layer, a rotatable blade roll outboard of the side of the frame, the blade roll having a plurality of blades spaced apart around its periphery for contact with and penetration of said items and into the peripheral working layer of the backup roll and a biasing system for biasing the blades of the blade roll and the backup roll together;
- the improvement comprising using as a biasing system an assembly for biasing the blade roll and the backup roll together with a substantially constant force, said assembly comprising a mechanical jack that extends and retracts as an element of the mechanical jack is rotated in one direction and in the opposite direction respectively to bias the blades of the blade roll against the backup roll, a motor for rotating that maintains a substantially constant and desired torque to the element of the mechanical jack during at least a portion of the setup and during operation of the chopper, said torque resulting in the blades of the blade roll penetrating the working layer of the backup roll only the desired depth.
A method of separating long lengths of unwound item(s) selected from the group consisting of fibers, fiber strands, string, yarn, wire, tape and ribbon into short pieces comprising feeding one or more items in an unwound form into a chopper comprising a frame, a rotatable backup roll outboard of one side of the frame, the backup roll having a peripheral working layer, a rotatable blade roll outboard of the side of the frame, the blade roll having a plurality of blades spaced apart around its periphery for contact with and penetration of said items and into the peripheral working layer of the backup roll and a biasing system for biasing the blades of the blade roll and the backup roll together;
- the improvement comprising using as a biasing system an assembly for biasing the blade roll and the backup roll together the desired amount, said assembly comprising a mechanical jack that extends and retracts as an element of the mechanical jack is rotated in one direction to bias the blades of the blade roll against the backup roll and in the opposite direction respectively to back the blades away from the blade roll, a programmable stepping motor for rotating that is programmable to move the number of steps to move the blades into a working layer of the backup roll a desired amount, measuring the diameter of a new or reconditioned backup roll being placed on or already on the chopper and inputting that information into the programmable controller or programmable stepping motor.
Dependencies are inferred from the claim text.