JPH0239722Y2 - - Google Patents

Description

[Detailed description of the invention] - Industrial application field This invention relates to a position detector for the cutting edge of a tool such as a cutting tool attached to a lathe. The present invention aims to provide a device that can accurately detect the position of the cutting edge, which serves as a reference for determining the feed amount.

・Conventional technology When turning a workpiece to a predetermined size using a lathe, the feed of the tool is determined by measuring the external shape of the workpiece in advance to determine the necessary feed allowance, and then determining the feed distance based on the position where the tip of the tool touches the workpiece. The tool is sent to the desired position.

In addition, in NC lathes, the position of the cutting edge of the tool corresponding to the position of the tool holder is set in advance in the NC device, and the tool is fed in according to the desired machining dimensions, but in this case, Since machining errors occur due to wear of the tool cutting edge, the set position must be corrected at predetermined intervals.

In addition, in NC lathes equipped with an automatic tool changer, the tool installation position varies by about 50 microns due to tool changes, so if you try to improve machining accuracy any further, the tool feed amount must be corrected each time the tool is changed. The need arises.

As a position detection device for the tool cutting edge used in such cases in turning processing, for example, the
Devices described in Japanese Patent Publication No.-27003, Japanese Patent Publication No. 58-47281, etc. are known, and conventional devices of this type include:
A contact member whose contact surface with the tool is a cylindrical surface is provided on the main body attached to the tail stock of a lathe and is biased in the advancing direction in the direction perpendicular to the main axis, and the displacement detection device detects displacement from the advancing position. is provided.

・Problems to be solved by the invention However, in the conventional device, the contact surface of the contact member was a convex cylindrical surface, and the tool was brought into contact with the contact surface from the outside, so the tool was not suitable for external machining. It is possible to detect the position of the cutting edge of a milling cutter or milling cutter, but in the case of an internal machining tool such as a boring tool, the position of the cutting tool changes significantly between machining and detection of the cutting edge, making the work inconvenient. However, there was a problem in that the measurement error also increased.

Therefore, the object of this invention is to obtain a tool cutting edge position detection device that can also accurately measure the cutting edge position of an internal diameter machining tool.

・Means for solving the problem The technical means adopted to solve the above problem will be explained using the reference numerals of the illustrated embodiment. Shank 1 that is fitted and fixed to the chuck
A contact member 3 is provided on a main body 2 having a shank, and is elastically biased by a stopper 10 that can freely advance in the direction normal to the central axis of the shank and that restricts the advance position. In the position detector of the tool cutting edge, which has a cylindrical surface having a central axis coinciding with the central axis of the shank 1, and is provided with a displacement detecting device 7 for detecting the advance and retreat of the contact member 3, A member 3 is provided to pass through the main body in the normal direction, and a medium convex cylindrical surface 13 for an outer diameter machining tool is provided at its advancing end, and a member 3 protrudes from the tip of the main body at its retreating end. A cylindrical collar 3a is provided, and the inner surface of this cylindrical collar is a hollow cylindrical surface 13a for use with an inner diameter machining tool.

・Function According to the position detector configured as described above,
The tool for outer diameter machining detects the position of the cutting edge by contacting with the convex cylindrical surface 13 at the advancing end of the contact member 3, and the tool for inner diameter machining detects the position of the cutting edge by contacting the inner convex cylindrical surface 13 at the advancing end of the contact member 3. Medium concave cylindrical surface 13 of the provided cylindrical collar 3a
The position of the cutting edge is detected by making contact with a. In this case, since the contact member 3 is pushed in the same direction due to the contact between the tool cutting edge and the cylindrical surfaces 13 and 13a, the common contact member 3 and position detector 7 are used to position the cutting edge of the tool for outer diameter machining. The position of the cutting edge of an internal diameter machining tool can be measured in the state closest to the machining state.

・Example The figure shows an example of this invention, in which 1 is a shank fitted to the tail stock of a lathe, 2
is a cylindrical body formed integrally with the shank 1,
3 is a contact member that penetrates the main body 2 in its normal direction (direction perpendicular to the axis of the shank 1); 6 is a set screw for fixing a micrometer; 7 is a micrometer;
8 is a guide hole provided in the main body 2 to guide the contact member 3; 9 is a coil spring that urges the contact member 3 in the advancing direction; 10 is a stopper formed at one end of the guide hole 8; 11 is the contact member The key groove 12a provided in the main body 2 is a pin 1 which is screwed into the main body 2 and whose tip is slidably fitted into the key groove 11.
3 is a convex cylindrical surface for an external machining tool formed on the advancing end of the contact member, 3a is a cylindrical collar fixed to the retreating end of the contact member 3 with a screw 15, and 13a is a concave part of the cylindrical collar 3a. It is a cylindrical surface.

The cylindrical surfaces 13 and 13a are cylindrical surfaces of predetermined dimensions having central axes that coincide with the central axis of the shank 1 when the contact member 3 is in its advanced position. That is, the cylindrical contact surfaces 13 and 13a of the contact member 3 and the cylindrical collar 3a are ground into cylindrical surfaces with the axis of the shank 1 as the central axis while the contact member 3 is fitted into the main body 2 and biased by the spring 9. It is processed.

The contact member 3 is provided so as to be able to freely slide but not rotate through the main body 2, and is biased in the advancing direction by a coil spring 9 interposed between the flange 3b at the tip thereof and the main body 2. There is. A cylindrical collar 3a for an internal machining tool is fixed to the base end of the contact member 3 with a screw 15, and a collar 17 is fitted between the cylindrical collar 3a and a stepped portion 16 provided on the contact member 3. When the collar 17 comes into contact with a stopper 10 provided on the main body 2 side, the advancing position of the contact member 3 is regulated. The cylindrical collar 3a has a concave cylindrical surface 13a.
Similar to the cylindrical surface 13 of the contact member 3, the cylindrical collar 3a
It must be provided so that it forms a cylindrical surface with a predetermined radius centered on the central axis of the shank 1 when it is in the extended position.

In addition, in the illustrated embodiment, the protrusion 1 is provided on the main body 2.
8, a through hole 19 is provided diagonally from this convex portion 18 toward the contact member 3, and a notch 20 is further provided in the contact member 3 opposite to the through hole 19. The micrometer 7 is inserted through the through hole 19 and fixed with the set screw 6 with its measuring end in contact with the notch 20. After the micrometer is fixed, its pointer is set to zero, and the movement of the contact member 3 is detected.

Generally, the tail stock of a lathe has a tapered hole, and the jaws of the chuck are parallel. Therefore, in order to attach the position detector of the present invention to the tail stock, shank 1 must be a tapered shank, and it is necessary to attach it to the chuck. To do this, shank 1 must be a straight shank. However, if a suitable adapter is fitted to the shank 1, it is easily possible to hold a tapered shank with the chuck or to fit a straight shank to the tailstock. Therefore, whether the shank 1 is a tapered shank or a straight shank can be determined depending on whether the shank 1 is to be installed more often, the chuck or the tail stock.

If the position detector configured as described above is attached to the tail stock or chuck of the lathe and the tip of the cutting tool 14 attached to the lathe body is brought into contact with the cylindrical surfaces 13, 13a of the contact member 3 or the cylindrical collar 3a, The contact member 3 retreats against the force of the spring 9 and rotates the pointer of the micrometer 7, so the bite 1
4 and the contact member 3 or the cylindrical collar 3a can be detected. When determining the reference position of the cutting tool 14, first bring the cutting edge of the cutting tool 14 into contact with the contact member 3 or the cylindrical collar 3a, and then gradually move the cutting tool 1
4 and detect the position where the pointer of the micrometer points to zero. In this case, the cutting edge is quickly retracted until just before the cutting tool 14 and the contact member 3 or the cylindrical collar 3a are separated, that is, just before the pointer of the micrometer 7 points to zero, and then the cutting tool 14 is gradually retreated until the micrometer 7 Since it is only necessary to detect the position where the pointer points to zero, workability is good and highly accurate measurements can be performed quickly.

Furthermore, the contact member 3 and the tool cutting edge have a cylindrical surface 13,
13a, so the tip of the cutting tool 14 touches the cylindrical surface 1 as shown by the imaginary line in FIG.
3, 13a, the dimension between the tip of the cutting tool 14 and the central axis of the workpiece is guaranteed.

・Effects of the invention As explained above, the position detector of the invention has
Since the reference position of the tool is detected by detecting the contact of the tool with the cylindrical surface of the accurately machined contact member using a displacement detection device such as a micrometer, the reference position of the tool cutting edge can be accurately and easily determined. This method has the effect of being able to measure the position of the cutting edge of the tool for outer diameter machining and the position of the cutting edge of the tool for inner diameter machining in a state closest to the machining state with a simple structure.

[Brief explanation of the drawing]

1 and 2 are views showing an embodiment of the present invention, in which FIG. 1 is a longitudinal sectional view of a position detector, and FIG. 2 is a front view thereof. In the figure, 1 is a shank, 2 is a main body, 3 is a contact member, 7 is a micrometer, 8 is a guide hole, 9 is a coil spring, 10 is a stopper, 14 is a bite (tool), 3a is a cylindrical collar, and 13 is a convex part Cylindrical surface, 13a
is a concave cylindrical surface.

Claims (1)

[Claim for Utility Model Registration] A contact member is attached to a main body having a shank that is fitted and fixed to the tail stock or chuck of a lathe, and is movable back and forth in the normal direction of the central axis of the shank, and has an elastic stopper that restricts the advancing position of the contact member. The contact member has a cylindrical surface having a central axis that coincides with the central axis of the shank in its advanced position, and a displacement detection device that detects the forward and backward movement of the contact member is provided. In the tool cutting edge position detector provided, a contact member is provided to penetrate the main body in the normal direction, and a convex cylindrical surface for an outer diameter machining tool is provided at the tip, and a convex cylindrical surface for an outside diameter machining tool is provided at the base end. A position detector for a tool cutting edge, characterized in that the cylindrical flange is provided with a cylindrical flange projecting from the end of the main body, and the inner surface of the cylindrical flange is a hollow cylindrical surface for use with an inner diameter machining tool.