CIRCULAR SAW CUTTING MACHINE

• US 20120297949A1
• Filed: 06/24/2010
• Published: 11/29/2012
• Est. Priority Date: 02/10/2010
• Status: Active Grant

• Current Assignee: Nishijima Kabushiki Kaisha
• Original Assignee: Nishijima Kabushiki Kaisha
• Inventors: Ono, Mitsuo
• Granted Patent: US 9,737,940 B2
• Time in Patent Office: Days
• US Class Current: 83/169
• CPC Class Codes: B23D 47/04 of devices for feeding, positioning, clamping, or rotating work
• CPC Class Codes: Y10T 83/263 With means to apply transient nonpropellant fluent material to tool or work
• CPC Class Codes: Y10T 83/4458 Work-sensing means to control work-moving or work-stopping means

Abstract

In a circular cutting machine, a main vice unit includes a stationary rear vice and a front vice disposed to be movable back and forth in a range between a position forward of a preset cutting position and a rearmost position where the rear ends of jaws come into contact with the front ends of jaws of the rear vice. The rear and front vices include clamping cylinders, respectively, that are independently controllable so as to independently clamp and unclamp their respective vices. When photoelectric sensors detect the rear end of work, the remaining length is calculated, which is then divided by the fixed-length feed amount to calculate remaining number of possible cutting operations. The remaining number of fixed-length feeding operations are continued to be carried out by using either a combination of the front vice and a transfer vice unit or the front vice alone to pull out the work.

Claims

1. A circular cutting machine comprising a headstock transfer unit for transferring a headstock between a standby position and a cutting position, the headstock mounting a circular saw motor for rotatably driving a circular saw blade;

a transfer vice unit for feeding work by advancing toward the cutting position;

a main vice unit for clamping the work at prescribed positions forward and rear of and across the cutting position; and

a fixed-length cutting controller for drivably controlling the circular saw motor, the headstock transfer unit, the transfer vice unit, and the main vice unit to perform fixed-length cutting of the work;

1) wherein the main vice unit comprises a rear vice fixed in forward and rearward directions in a prescribed position rear of the cutting position and a forward vice having, as its preset position during cutting, a prescribed position forward of and across the cutting position from the rear vice, the forward vice being movably disposed in the forward and rearward directions in a range between a position forward of its preset position and a rearmost position where rear ends of jaws of the front vice are in contact with front ends of jaws of the rear vice, the front vice and the rear vice including separate clamping cylinders capable of being independently controllable to perform clamping and unclamping independently;

(2) the circular cutting machine further comprising work end detection sensors for detecting a rear end of the work; and

(3) wherein the fixed-length cutting controller is configured to perform control process to implement the following means;

(3A) a fixed-length cutting means for cutting the work to a fixed-length by repeating the control process of;

causing the transfer vice unit to clamp the work at a standby position and advance a fixed-length feed amount from the standby position with the front vice and the rear vice remaining unclamped;

after the advance is completed, causing the front vice and the rear vice to clamp the work in their respective prescribed positions forward and rear of a cutting line;

driving the circular saw motor and the headstock transfer unit to cut the work;

after the cutting of the work is completed, causing the transfer vice unit, returned to its standby position, to clamp the work;

causing the front vice and the rear vice to unclamp the work;

after causing the transfer vice unit to advance the fixed-length feed amount from the standby position with the work clamped by the transfer vice unit, causing the front vice and the rear vice to clamp the work in their respective prescribed positions forward and rear of the cutting line; and

driving the circular saw motor and the headstock transfer unit to cut the work;

(3B) a determination means for calculating a remaining length of the work currently undergoing fixed-length cutting based on detection signals from the work end detection sensors and determining whether or not the remaining length has become insufficient to permit the transfer vice unit to advance the work the fixed-length feed amount;

(3C) a work pullout means for, if the determination means determines that the remaining length of the work has become insufficient to permit the transfer vice unit to advance the work the fixed-length feed amount, causing the front vice to retract to the rearmost position while remaining unclamped from the work, and then causing the front vice alone to clamp and advance the work a predetermined pullout amount so as to position the work, which can no longer be fed the fixed length, forward of the cutting line the length equivalent to the fixed-length feed amount; and

(3D) a work remainder cutting means for, after the work pullout means is actuated to cause the front vice to pull out the work, causing the rear vice to clamp the work and the front vice to unclamp the work and retract;

causing the front vice to stop at the prescribed position forward of the cutting position and then clamp the work again; and

driving the circular saw motor and the headstock transfer unit to cut the work, which is clamped by the front vice and the rear vice in the prescribed positions forward and rear of the cutting position so as to further cut the work remainder, which can no longer be transferred the fixed-length feed amount by the transfer vice unit.

2. The circular cutting machine according to claim 1, wherein the fixed-length cutting controller further comprises:

(3E) the work pullout means being configured to advance the front vice from the rearmost position the fixed-length feed amount with the work clamped by the front vice.

3. The circular cutting machine according to claim 1, wherein the fixed-length cutting controller further comprises the following future:

(3F) the work pullout means being configured to;

cause the transfer vice unit to clamp the work after moving forward of the standby position and move to a forward end from that clamping position;

cause the transfer vice unit, currently in the forward end, to pass the work to the main vice unit while the transfer vice unit is clamping the work by causing the rear vice of the main vice unit to clamp the work;

cause the front vice to unclamp the work and retract to the rearmost position; and

then cause the front vice alone to clamp the work in the rearmost position and advance the work the distance equivalent to the fixed-length feed amount minus the foregoing forward movement of the transfer vice unit so as to carry out the pullout of the work.

4. The circular cutting machine according to claim 1, further comprising:

(4) air nozzles provided in proximity to a cutting edge of the circular saw blade mounted on the circular saw motor, for discharging compressed air in the direction feeding the work; and

(3G) the fixed-length cutting controller being further configured to perform control process to implement a saw-blade return control means for causing the transfer vice unit to clamp and slightly retract the work when the headstock transfer unit retracts the circular saw motor from the cutting position to the standby position until the determination means determines that the remaining length of the work has become insufficient to permit the transfer vice unit to advance the work the fixed-length feed amount, and after the determination means determines that the remaining length of the work has become insufficient to permit the transfer vice unit to advance the work the fixed-length feed amount, the saw-blade return control means causing the circular saw motor to start retraction after causing compressed air to be discharged from the air nozzles when the headstock transfer unit retracts the circular saw motor from the cutting position to the standby position, the saw-blade return control means continuing to cause compressed air to be discharged from the air nozzles at least until after the cutting edge of the circular saw blade clears the cut surface of the work toward the standby position.