JPS6240755Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a cutting tool edge position detection device for a machine tool.

As cutting technology becomes more sophisticated, one of the most important issues is the development of cutting tools that directly affect the workpiece. That is, the development of new materials for chips with the aim of increasing speed and longevity, and the sophistication of coating technology. On the other hand, with the automation of cutting technology, the development of peripheral devices has progressed rapidly, and most machines are now equipped with edge measuring devices. Under these circumstances, there are conventional tool edge position detection devices that detect the edge position from multiple directions using a single limit switch. This requires conversion, which not only complicates the structure but also increases its size. Furthermore, since the mechanical movement direction changing mechanism is employed, the position of the limit switch is fixed, so changes between different models cannot be freely accommodated, and redesign is required each time.

Based on the above-mentioned background, the present invention improves the conventional contact-type cutting edge position detection device (hereinafter referred to as a touch sensor), making it particularly compact, and detecting the tool cutting edge position with a structure that can be freely adapted to machines of any structure. The purpose is to provide equipment.

That is, the purpose of the present invention is to utilize the basic configuration of the conventional device to detect the position of the cutting edge of a non-conductive cutting tool with a simple configuration and a configuration that can be applied to any type of machine. .

Hereinafter, embodiments of the present invention will be described based on the drawings. FIG. 1 shows a transfer type touch sensor applied to a numerically controlled lathe. Reference numeral 1 denotes a chuck attached to the main shaft, which grips and rotates a workpiece 3 with gripping claws 2. A cutting tool fixed to one end of a tool post 4 (Fig. 2) mounted and fixed on a moving device (not shown) that can move in two directions, perpendicular to the spindle axis (X direction) and parallel to the spindle axis (Z direction). The workpiece 3 is formed into a predetermined size by T. 1 and 2 show that after the machining of the workpiece 3 is completed and before the next cutting starts, the retractable touch sensor is retracted into the machining area, and then the cutting tip C is brought into contact with the touch sensor. This shows the state in which the position of the blade edge relative to the reference position is detected.

When the workpiece 3 is being processed, the arm 5 of the touch sensor is in a retracted position away from the processing area, as shown by the imaginary line in FIG. One end of the arm 5 is fitted into one end of the shaft 6, and the two are integrated with a nut 7 and a screw 8. The shaft 6 is inserted through the body 9 and rotatably supported by bearings 10, 10.

Note that movement of the shaft 6 in the axial direction is restricted by a nut 11. A hydraulic rotary motor 12 is connected and fixed to the other end of the shaft 6. A direction switching device (not shown) selects the direction in which the hydraulic pressure flows out to the pipes 13 and 14, and the shaft 6 and arm 5 are reciprocated. Therefore, the arm 5 can swing between the cutting edge detection position and the retracted position. The shaft 12a of the hydraulic rotary motor 12 is fitted into the other end of the shaft 6, and transmits rotational force via the key 15.

The detector 16 is attached to the side wall of the body 9. Covered electric wire 17 connected to one end of detector 16
extends through the hollow portion 5a to the distal end portion 5b of the arm 5. In this embodiment, the detector 16
is attached to body 9, but arm 5
It can also be attached to. Covered wire 17 at tip 5b
The end of the screw 1 is embedded in the insulating plug 18.
It is fixed at 8a. Furthermore, a conductor 19 is fixed to the tip of the covered wire 17 (FIG. 4) and stands upright outward. The conductor 19 is made of elastic spring steel or the like, and has a probe 20 at its tip.

A spool 21 is arranged at a fixed distance from the feeler 20 in the moving direction of the tool rest 4, that is, in the X direction and the Z direction.
It is arranged so that it can slide parallel to the direction. The spool 21 is fitted into a block 22, and a snap ring 23 for regulating the amount of movement in the sliding direction is fitted into one end. The block 22 is fixed on a plate 24 with bolts 25, and the plate 24 is further fixed on the upper part of the arm tip 5b with a plurality of bolts 26 and 27. The other end of the spool 21 engages with a leaf spring 28 fixed to the block 22, urging the spool 21 toward the opposite side of the probe 20. Therefore, the spool 21 normally maintains its position with the side surface of the snap ring 23 elastically abutting against the block 22. Also, spool 2
One end of the probe 1 is spaced apart from the probe 20 by a constant distance.

The conductor 19 is erected through the hole 24a of the plate 24. The insulating tube 2 is placed around the hole 24a.
9, and a protective insulating cover 30 is attached to the arm 5. Therefore, when the spool 21 and the feeler 20 disposed on the arm 5 are separated from each other by maintaining a constant distance, the conduction state of the circuit of the touch sensor is interrupted.

In FIGS. 1 and 2, the present invention has a swing-type retraction function, and a flat plate 31 is attached to the lower part of the arm 5 so as to protrude around the periphery. On the other hand, a cover 32 fixed to the body 9 is provided, and a partially opened box 32a for accommodating the arm 5 during retraction is integrally installed on the upper part. Therefore, when the arm 5 is rotated by the operation of the hydraulic rotary motor 12, the arm 5 moves toward the box 32.
It is accommodated in a. Arm 5 is box 32a
It is sealed by a plate 31 and protected from chips, cutting oil, etc. during cutting.

A dog 33 is fixed to one end of the rear part of the hydraulic rotary motor 12 with a screw 34, and a dog 33 is fixed to one end of the rear part of the hydraulic rotary motor 12.
rotates with Two limit switches 35a and 35b disposed on the outer periphery generate signals under the action of the dog 33 to confirm the operation of the hydraulic direction switching device (not shown). The detection position of the arm 5 is accurately positioned using the stopper 36 (second
figure). Further, even in the retracted position, although not shown, a similar stopper is used.

Next, the operation of detecting the position of the cutting edge according to the present invention will be explained.

While the workpiece 3 is being cut by the cutting tool T, the arm 5 of the touch sensor is in contact with the box 32a as described above.
It is housed in the retracted position (imaginary line in Figure 2). When cutting of the workpiece 3 is finished and measurement is started,
The workpiece 3 is removed from the gripping claws 2, and the hydraulic rotary motor 12 is activated. The hydraulic rotary motor 12 rotates clockwise in FIG. 2, and the dog 33 depresses the limit switch 35a to take a confirmation signal. That is, the arm 5 rotates and comes into contact with the stopper 36, and is fixed at the detection position. The tool rest 4 on which the cutting tool T is disposed moves in the X or Z direction according to a command from the NC device, and starts detecting the position of the cutting edge of the chip C relative to the reference position. The tool rest 4 moves in a direction approaching the arm 5, and the cutting edge of the tip C comes into contact with one end 21a of the spool 21. FIG. 2 shows the position detection operation in the X direction, in which the tip C moves the spool 21 against the leaf spring 28. The other end 21b of the spool 21 comes into contact with the feeler 20 and stops moving after reaching the command value. As mentioned above, spool 2
When the touch sensor 1 contacts the touch sensor 20, the circuit of the touch sensor becomes conductive, and the detector 16 immediately outputs a detection signal. Therefore, from the reference position of tip C to the contact position, that is, the amount of movement of the cutting edge,
It can be accurately measured by a known measuring means (not shown). By interposing the spool 21 between the tip C and the feeler 20, a touch signal can be obtained even if the tip C is a non-conductive cutting tool made of a new material. Therefore, by comparing the previously stored movement command value of the cutting edge with the measured value, the state of wear and damage of the chip C can be determined. When the detection operation is completed, the tool rest 4 separates from the arm 5, and the spool 21 and the feeler 20 return to a position separated by a certain distance by the action of the leaf spring 28.
The arm 5 is rotated counterclockwise in FIG. 2 by the operation of the hydraulic rotary motor 12, and is accommodated in the box 32a. At this time, the dog 33 is the limit switch 3.
Step on 5b to get a confirmation signal.

As mentioned above, even if the cutting tool tip of the machine tool is made of a non-conductive material, the contact signal can be obtained. Loss detection can be performed. In addition, the measuring head is compact and has a simple structure that is not limited by the mounting position of the detector, so it can be simply attached to an existing mechanism, making it compact and economical. Furthermore, since it is a transfer type touch sensor, accurate position detection is possible without being affected by chips or cutting oil.

As mentioned above, the present invention is not limited to the configurations shown in the embodiments, and modifications are expected without departing from the technical idea of the present invention as described in the claims.

[Brief explanation of the drawing]

FIG. 1 is a plan longitudinal cross-sectional view showing one embodiment of the present invention, FIG. 2 is a view taken in the direction of arrow A in FIG. BB sectional view of the figure. In the figure, 5...arm, 6...axis, 9...
Body, 12... Hydraulic rotation motor, 16... Detector, 18... Insulating plug, 19... Conductor, 20...
...Touch, 21...Spool, 22...Block,
23... Snap spring, 28... Leaf spring, 31
...Board, 32a...Box.

Claims (1)

[Scope of utility model registration request] In a tool edge measuring device for a numerically controlled machine tool in which a cutting tool moves in a first direction and a second direction that are orthogonal to each other to machine a workpiece, the cutting tool is moved in the first direction and the second direction. an arm movable within a movement range of the arm, a block provided at the tip of the arm, and an arm provided on the outer periphery of the block so as to be slidable in the first direction and always protruding toward the outer periphery with a spring. a second spool provided on the outer periphery of the block so as to be slidable in the second direction and always protruding toward the outer periphery with a spring;
a spool, a tactile support made of an electrically conductive and elastic material and provided on the arm through an insulator in a direction perpendicular to the sliding direction of the first spool and the second spool; a feeler attached to the tip of the child support with a constant gap between the first spool and the second spool; one end connected to the feeler support and the other end connected to the conductive portion of the arm; a detector connected to the spool, and when the first or second spool is pushed inward by the cutting edge of the cutting tool and either spool comes into contact with the feeler,
A cutting tool blade edge position detection device characterized by forming a loop circuit.