JPS5950446B2 - Flexible tool holder adjustment device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION In boring operations such as machining centers, the cutting edge of the cutting tool wears out as the number of boring operations increases, causing minute dimensional errors in the workpiece.

The present invention relates to a device that makes it possible to correct minute errors by pressing and deforming a boring tool from the back, and it is also capable of automating the correction work by incorporating it into a tool holder.

Examples will be described with reference to the drawings.

The main shaft 18 is rotatably supported by a main shaft head 19, and the cutting tool holder 1 is detachably attached to the main shaft 18.

The tool holder 1 is made by integrating a shank portion 1a and a tool mounting portion 1b with bolts 2, and both portions 1a are attached to the outer periphery.
, lb, and an annular groove 1C is carved therein.

The cam ring 3 has a protruding cam 3a on its inner surface that fits into the annular groove 1C, and is rotatably fitted onto the outer periphery of the tool holder 1.

However, a radial blind hole 1d is bored in the tool holder 1, and a corresponding recess 3b is provided on the inner surface of the cam ring, between which a ball 16 and a spring 17 are inserted.

That is, a notch mechanism is formed, and the cam ring normally rotates integrally with the tool holder 1.

On the other hand, an engaging edge 3C is curved on the outer periphery of the cam ring, and the cam ring can be prevented from rotating by engaging the engaging edge 3C with a locking rod 4 attached to the spindle head 19 so as to be removable and removable.

However, during processing, the locking rod 4 is in a detached state.

The ratchet shaft 5 is rotatably supported on the tool mounting portion 1b of the tool holder 1 parallel to the main shaft axis, and has a ratchet shaft 6 fixed to its inner end and a disc cam 7 fixed to its outer end.

One end of the flexible cutting tool 8 is fixed to the outer periphery of the tool mounting part with a bolt 9, and a radial hole is bored in the main shaft at the other end on the back side, into which a pin 10 is slidably inserted.

The pin 10 has one end in contact with the back surface of the flexible cutting tool 8, and the other end in contact with the cam surface of the disc cam 7.

The disc cam has a cam surface that progressively increases in radius from low to high.

Therefore, by rotating the disc cam 7, the cutting tool 8 can be pushed outward via the pin 10.

The cutting tool 8 is provided with an appropriate notch 8a so as to allow the cutting edge of the cutting tool to be slightly bent by this pressure.

A pin 11 is fixed inside the tool holder 1 parallel to its axis.

The swinging arm 12 has a bell crank shape, and one end thereof is rotatably supported by the pin 11, and the other end can pass through a hole bored in the bottom of the annular groove of the tool holder and come into contact with the inner surface of the cam ring.

Further, the swing arm 12 is constantly pressed against the inner surface of the cam ring by a spring 15, which will be described later.

The claw arm 13 is pivoted at one end to the bent base of the swinging arm by a shaft 14, and has a claw 13a pivoted near the side end.

The pawl 13a engages with a tooth notch on the outer periphery of the ratchet shaft 6, and can rotate the ratchet shaft 6 by one pitch each time the pawl arm reciprocates.

A spring 15 is installed between the claw arm 13 and a part of the wall surface of the tool holder.
is inserted, and the spring 15 is connected to the swing arm 12 via the claw arm 13.
Press it against the inner surface of the cam ring as described above.

The present invention is configured as described above.

First, the main shaft 18 is stopped at a predetermined angular phase with respect to the main shaft head 19, and the locking rod 4 is advanced to stop the cam ring 3 from rotating.

At this time, since the cam ring 3 is held at a specific position relative to the tool holder 1 by the notch mechanism, the locking rod 4 and the engagement edge 3C of the cam ring 3 are aligned.

When the main shaft is then slowly rotated, the end of the swing arm 12 slides while pressing against the inner surface of the stopped cam ring, swinging once while riding over the cam ring protrusion 3a.

Along with this, the pawl arm 13 reciprocates once, causing the pawl wheel to rotate one pitch.

The disc cam also rotates, pressing the back surface of the tool holder via the pin 10 and slightly displacing it outward.

After this, the locking rod 4 is moved backward, and then the main shaft 18 is caused to perform normal cutting rotation.

The present invention can create other embodiments without changing its gist.

The one illustrated in Fig. 4 is one of them, which includes a ring 6A for the ratchet 1 with an internal thread, a ratchet shaft 5A with a threaded portion that engages with the internal thread, and a ratchet shaft 5A that is fixed to the ratchet shaft 5A and has an attached ring 6A. It is prevented from rotating by the key 7B, and by moving the ratchet shaft 5A in the axial direction, the tool 8 is rotated through the pin 10.
The cam 7A has a conical cam surface that can press the cam 7A.

All other structures are the same as the embodiment shown in FIG. 1, and the rotation of the ratchet shaft 6A causes the ratchet shaft 5A to step in the axial direction, giving a small deviation to the cutting tool 8 each time. .

The cam only needs to have a tapered surface that contacts the pin 10, and does not necessarily need to be conical.

In the present invention, if the relationship between the number of pieces to be machined and the amount of wear on the cutting edge is understood through experience, everything can be fully automated by including the corresponding operations in the NC tape.

It can also be automated by measuring the inner diameter after boring using a measuring device such as an air micro, and inputting it into the NC tape as an auxiliary function to adjust the position of the tool tip by a value that corresponds to the amount of wear determined. can.

A feature of the present invention is that since the deflection of the cutting tool holder is utilized, it is possible to correct very small amounts of wear.

[BRIEF DESCRIPTION OF THE DRAWINGS] Fig. 1 is a cutaway front view of the present invention, Fig. 2 is a cutaway side view of the vicinity of the check ring, Fig. 3 is an explanatory view of the engagement between the main shaft and the cam ring, and Fig. 4 is a cutaway front view of the present invention. FIG. 7 is a cutaway front view of another embodiment. 1-bit holder, 1a-shank part, lb-bit mounting part, IC-annular groove, 1d-blind hole, 2-bolt, 3
- cam ring, 3a - protrusion, 3b - recess, 3C - engaging edge, 4 - locking rod, 5 - ratchet shaft, 6 - ratchet shaft,
7-disk cam, 8-center rebit, 8a-notch, 9-bolt, ]0, 11-pin, 12-swing arm, 13-claw arm,
13a-claw, 14-shaft, 15-spring, 16-ball, 17-
Spring, 18-main shaft, 19-spindle head, 6A-ratchet shaft, 5A-ratchet shaft, 7A-cam, 7B-key.

Claims (1)

[Claims] 1. A spindle rotatably provided to the spindle head of a machine tool;
A tool holder that integrally comprises a shank part that can be attached and detached from the main shaft and a tool mounting part that has a flexible tool on the outer periphery of the tip, and that spans both parts and has an annular groove on the outer periphery, and that can be inserted into the annular groove. a cam ring provided with a convex cam and rotatably fitted into the annular groove; a cam ring detent device provided on the spindle head near the spindle and capable of engaging and disengaging from the cam ring;
a transmission shaft that is rotatably supported in the tool holder and has a ratchet ring fixed to one end; a swing arm that is swingably supported in the hollow of the tool holder and makes sliding contact with the inner surface of the cam ring; a ratchet wheel progressive rotation mechanism consisting of a pawl arm that is attached to the ratchet wheel and can be engaged with the outer peripheral notch of the ratchet ring; and a disk that is fixed to the other end of the transmission shaft and presses and expands the bending tool by rotation of the transmission shaft. A flexible tool holder adjustment device consisting of a cam and a cam. 2. A spindle rotatably installed on the spindle head of a machine tool,
A tool holder that integrally comprises a shank part that can be attached and detached from the main shaft and a tool mounting part that has a flexible tool on the outer periphery of the tip, and that spans both parts and has an annular groove on the outer periphery, and that can be inserted into the annular groove. a cam ring provided with a convex cam and rotatably fitted into the annular groove; a cam ring detent device provided on the spindle head near the spindle and capable of engaging and disengaging from the cam ring;
an advancing/retracting shaft that is supported so as to be movable in the axial direction within the tool holder and has a threaded end at one end and screwed together with a ratchet ring having a tapped hole; and the cam ring that is pivotally supported in a manner that is swingable within the space above the tool holder. A ratchet wheel progressive rotation mechanism consisting of a swinging arm that slides on the inner surface, a claw arm that is pivotally attached to the swinging arm and can engage with the outer peripheral notch of the ratchet wheel, and a ratchet wheel that is fixed to the other end of the movement shaft and moves back and forth. A flexible tool holder adjustment device comprising: a cam having a tapered surface that can press and expand a flexible tool by moving the shaft forward or backward;