JPH01264748A - Tool adapter with built-in speed increase mechanism - Google Patents

Abstract

PURPOSE:To improve the precision of processing by providing between the fixed portion and the tool gripping portion of a tool adapter a rotation detecting device detecting the rotational state of the tool gripping portion, and conducting the control of a motor so that an actual rotational state may agree with a predetermined rotational state. CONSTITUTION:When a main shaft S furnished with a tool adapter with a built-in speed increase mechanism is driven in rotation by means of a servo motor M, a rotation portion A is rotated in one body with the main shaft S against a fixed portion B whose rotation is checked by means of a rotation stopping pin 18, and a tool T is rotated in speed increase by means of a speed increase mechanism consisting of a fixed wheel 15, a planetary roller 13 and a sleeve 20. The rotary plate 22 of a rotary encoder is rotated in one body with the sleeve 20 during processing, and its rotational state is detected by means of an element 16 on the side of fixation, and its signal is inputted into the controller of the servo motor M through a connection plug 30 and a guide line L2. And the servo motor M is controlled so that the actual rotational state of the tool T may agree with a predetermined rotational state. Accordingly, even if there occurs a slippage at a planetary mechanism, a tool rotation is maintained in a predetermined state.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a tool adapter that is detachably attachable to the main shaft of a machine tool and that incorporates a friction transmission planetary speed increasing mechanism.

[Conventional technology]

In the prior art, a friction transmission planetary mechanism has been used as a speed increasing mechanism in a tool adapter that is detachably attached to the main shaft of a machine tool and is equipped with a speed increasing mechanism because of various advantages.

[Problem to be solved by the invention]

When a friction transmission planetary mechanism is used as a speed increasing mechanism for increasing speed in a conventional tool adapter, the rotation of the output shaft (cutting tool mounting socket) is not completely dependent on the rotation of the input shaft (main shaft). the result.

The rotation of the output shaft is outside the automatic control loop for the rotation of the main shaft, and the advantages of automatic control cannot be fully utilized.

For example, in the case of a vertical tap, the feed amount is linked to the number of rotations of the tap, but the cutting resistance causes slippage in the friction transmission planetary mechanism, and the feed of the spindle is not performed regardless of the rotation of the tap. However, there are cases where the tap is not set accurately.

The present invention seeks to eliminate such drawbacks of conventional tool adapters.

[Means to solve the problem]

The tool adapter with a built-in speed increasing mechanism according to the present invention has a fixed part that is coupled to the fixed side of a machine tool or the like in a manner that can be freely engaged and disengaged, and a part that is rotatably supported within the fixed part and is attached to the main shaft. A tool that includes a rotating part formed at the protruding rear end, a rotating part rotatably supported in a fixed part, connected to the single rotating part via a friction transmission planetary speed increasing mechanism, and a tool gripping part formed at the tip. A rotation detection device that is interposed between the gripping portion, the fixed portion, and the tool gripping portion and detects the rotation state of the tool gripping portion, and a rotation detection device that sends a detection signal from the rotation detection device to an external control device. and a connector to which an external conductor can be detachably connected.

[For production]

The rotating part of the tool adapter with a built-in speed increasing mechanism, which has the desired tool attached to the tool gripping part, is attached to the main shaft, and the fixed part is also connected to the fixed side of the machine tool, etc.

Then, when the main shaft is rotationally driven, the rotating part rotates with respect to the fixed part, and the rotation is P2! The speed is increased and transmitted to the tool gripping section via the frictional planetary speed increasing mechanism, and the tool rotates at a higher speed than the rotation of the main shaft. As the spindle moves forward, the tool processes the workpiece.

The one-rotation detection device during machining detects the rotational state of the tool gripping portion, that is, the tool, and its detection signal is input to the control device of the motor for driving the rotation of the spindle via a conductive wire connected with a connector. At that time, even if the actual rotation of the tool lags behind the predetermined rotation due to slippage of the friction transmission planetary speed increasing mechanism and a rotation phase difference occurs, the control device does not recognize the actual rotation state of the tool, which is the detection signal. The electric motor is controlled to match a predetermined rotational state.

〔Example〕

Embodiments of the invention will be described with reference to the drawings.

In Fig. 1, the tool adapter with built-in speed increasing mechanism is shown.

A rotating part A that is inserted into the main shaft S of a machine tool, a fixed part B that is removably coupled to a fixed side of the machine tool, such as a main spindle head H, and a tool gripping part C that grips the shank of a tool. The six-rotation part A is formed by coaxially coaxially forming a shaft part 1 at the tip, a collar part 2 with an annular groove in the middle, and a tapered shank 3 at the rear end. Axial pins 4, 4.4 for planetary rollers are mounted on the tip surface of the shaft-shaped portion 1 at equal intervals around the circumference and in the axial direction, and rolling bearings (for example, angular ball bearings) 5.5 are mounted on the outer peripheral surface. The inner ring of is fixed. The annular groove 6 of the collar 2 engages with a hand of an automatic tool changer. A screw hole 7 into which a tension rod is screwed is formed in the rear end surface of the taper shank 3, and the taper shank 3 is inserted into a taper hole 26 of a main shaft S of a machine tool.

The fixed part B is formed by integrating or combining a small diameter housing part 8 at the tip and a large diameter housing part 9 at the rear end, and a small diameter hole 10 in the small diameter housing part 8 and a large diameter hole in the large diameter housing part 9. 11 is a double stepped portion 12 that communicates coaxially with
, 12'.

The outer ring of the rolling bearing 5 is fixed to the large diameter hole 11 of the large diameter housing portion 9 . That is, the shaft-like part 1 of the rotating part A is inserted into the large-diameter hole 11 of the fixed part B, and is rotatably attached via the rolling bearing 5.5.

Each planetary roller 13 is mounted on a needle roller bearing 14 in a space formed between the distal end surface of the shaft portion 1 and the stepped portion 12 of the stepped hole.
It is rotatably supported by each shaft pin 4 via the shaft pin 4, and its outer circumferential surface is in contact with the inner circumferential surface of a fixed ring I5 fitted in the front part of the large diameter hole 11.

The fixed element 16 of the rotary encoder R is attached to the fixed part B in a space formed between the planetary roller 13/shaft pin 4 and the stepped part 12' of the stepped hole.

A connection socket 17 is opened and attached to the rear end surface of the large-diameter housing portion 9 . The connection socket 17 and the fixed element 16 of the rotary encoder R are connected by a conductive wire L1 buried in the large diameter housing part 9. Anti-rotation pins 18 are installed at different positions in the circumferential direction.

The connection socket 17 may be provided on a detent pin 18 implanted on the rear end surface of the large-diameter housing portion 9. The taper shank of the tool T is inserted into the tip of the tool gripping portion C. It is a sleeve 20 in which a tapered hole 19 is formed, and is rotatably inserted into the small diameter hole lO of the small diameter housing part 8 via a rolling bearing (for example, an angular contact ball bearing) 21, and its rear end is connected to the large diameter housing part. The planetary rollers 13, 13.13 protrude into the large diameter hole 11 of No.
are in contact.

After all, the fixed shaft 15, the planetary rollers 13, 13.13, and the sleeve 20 constitute a planetary speed increasing mechanism.

A rotating plate 22 corresponding to the fixed element 16 of the rotary encoder R is attached to the sleeve 20 behind the rolling bearing 21.21.

Note that 23 is a labyrinth shield.

In the spindle head H to which the tool adapter is attached, the tip of the hollow hole 25 of the spindle S rotatably supported by the spindle head housing 24 becomes a tapered hole 26 into which the taper shank 3 of the tool adapter is inserted.

A tension rod 27 that is removably screwed into the screw hole 7 of the tapered shank 3 is inserted into the hollow hole 25 .

Further, a rotor 28 of an AC servo motor M is attached to the main shaft S so as to face a stator 29 installed in the main shaft head housing 24 .

On the tip surface of the spindle head housing 24, there is a connection socket 17 and a rotation stopper pin 18 for the installed tool adapter.
A connection plug 30 and a rotation prevention fixing member 31 are provided at positions facing each other, and the connection plug 30, which is movable in the axial direction, can be engaged with the connection socket 17, and the rotation prevention member 31 can be engaged with the rotation prevention pin 18, respectively. .

The connection plug 30 is fitted into a cylinder hole 32 formed in the spindle head housing 24 and is supplied to the cylinder hole 32 via a passage 33 bored in the spindle head housing 24 and a conduit 34 connected thereto. It is attached to the tip of a piston rod 36 that is protruded by a pressure fluid and retracted by a compression spring 35. For the connection plug 30.

It is connected to an external main shaft rotation drive electric motor control device (not shown) via a conductive wire L2.

The above-mentioned fluid pressure cylinder as a means for moving the connecting plug 30 forward and backward is one example, and other suitable means, such as an electromagnetic type as shown in FIG. 2 or an electric motor type as shown in FIG. 3, may be used. may be applied.

In the electromagnetic type, a solenoid 37 is provided in a portion corresponding to the cylinder hole of the fluid pressure cylinder, and a portion corresponding to the piston is provided in a movable iron core 3.
It is 8.

The electric motor type has a small electric motor 39 in the spindle head housing 24 and an axial ball screw 40 that is rotationally driven by the electric motor 39.
is attached, and the connection plug 30 is screwed into the ball screw 40.

An operator may directly attach and detach the connection plug 30 to which the conductive wire L2 is connected to and from the connection socket 7 without providing a means for moving the connection plug 30 forward and backward.

Although the main shaft ff1H with a built-in electric motor is illustrated in FIG. 1, a type in which an electric motor for driving the rotation of the main shaft is independently installed in the main spindle head [1] may also be used.

The operation of the above-mentioned tool adapter with built-in speed increasing V1 structure will be described.

By inserting the shank of a desired tool T into the tapered hole 19 of the sleeve 20, the tool T is held by the tool adapter with a built-in speed increasing mechanism.

This is a tool adapter with a built-in speed increase mechanism that has been installed with the tool'IA.

For example, it is stored in a tool magazine of a machining center, and the annular groove 6 of the flange 2 is gripped by a replacement hand.
It is attached to the spindle S of the spindle head H of a machining center. That is, the taper shank 3 is inserted into the taper hole 26 of the main shaft S, the tension rod 27 is screwed into the screw hole 7, and the taper shank 3 is inserted into the taper hole 26 of the main shaft S.
By drawing in the.

The tool adapter with built-in speed increasing mechanism is fixed to the spindle S.

At this time, the rotation stopper pin 18 of the large diameter housing portion 9.

It is engaged with the rotation prevention member 31 of the spindle head H.

On the other hand, when pressure fluid is supplied to the cylinder hole 32 via the conduit 34 and the passage 33, the compression spring 35 is compressed, the piston rod 36 protrudes, and the connection plug 30 is coupled to the connection socket 17, so that , the fixed side element 16 of the rotary encoder R is connected to the conductive wire L1. Connection socket 17. It is connected to a control device for an AC servo motor M (not shown) via a connection plug 30 and a conducting wire L2.

In the electromagnetic advance/retreat drive means for the connection plug 30, by closing the excitation circuit of the solenoid 37, the movable iron core 38 compresses the compression spring 35 and causes the connection plug 30 to protrude. The connection plug 30 is thereby coupled to the connection socket 17.

In the electric motor 3jX drive means of the connection plug 30, the ball screw 40 is rotated by the operation of the small electric motor 39.

As a result, the connection plug 30 moves forward, and the connection socket 1-1
Combined with 7.

In this way, when the main shaft S equipped with the speed increasing mechanism built-in tool adapter is rotationally driven by the AC servo motor M, the one-rotation part A is rotated in contrast to the fixed part B whose rotation is suppressed by the one-turn stop pin 18. It rotates together with the main shaft S. Therefore, the planetary rollers 13, 13.13 in contact with the fixed ring 15
revolves and rotates on its axis. Then, the planetary roller 13
, 13.13, the sleeve 20. That is, tool T is 1
The rotating part A, that is, rotates at a faster speed than the rotation of the main shaft S.

In this way, the tool T performs a predetermined machining on the workpiece by advancing the spindle head H. Tool T due to cutting resistance at that time
The thrust load on the sleeve 20. Rolling bearing 2
1 , 21 is supported by the main shaft S via the fixed part B, the rolling bearing 5.5, and the rotating part A.

During processing, the rotating plate 22 of the rotary encoder R.

Sleeve 20. In other words, it rotates together with the tool T, and its rotational state is determined by the fixed side element of the rotary encoder R! 6, and the detection signal is transmitted through the conductor LL and the connection socket 17. The signal is input to a control device for the AC servo motor M (not shown) via the connection plug 30 and the conductor L2. At this time, even if the actual rotation of the tool T lags behind the predetermined rotation due to slippage of the friction transmission planetary speed increasing mechanism and a rotation phase difference occurs, the control device will detect the actual rotation of the tool T, which is the detection signal. The AC servo motor M is controlled so that the state matches a predetermined rotation state.

For example, in the case of a tap stand, the rotation of the tap, which should have a constant relationship with the feed, is maintained constant.

Although the above-mentioned embodiment has been described with reference to the application to a machining center, it is easily understood that the invention can be applied not only to other machine tools but also to portable movable crab tools.

〔Effect of the invention〕

The tool adapter with a built-in speed increasing mechanism according to the present invention has a speed increasing V&
In addition to having the advantage of using a friction transmission planetary mechanism as a structure, the disadvantage of slippage due to cutting torque that occurs due to the friction transmission planetary mechanism is eliminated despite the use of a friction transmission planetary mechanism.

That is, even if the friction transmission planetary mechanism slips due to cutting torque, the rotational state of the tool is maintained at a predetermined state. Machining precision is thereby also maintained and failures due to slippage are avoided.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional front view of a tool adapter with a built-in speed increasing mechanism and a spindle head to which it is attached in an embodiment of the present invention, and FIGS. 2 and 3 are speed increasing mechanisms in an embodiment of the present invention. FIG. 7 is a schematic diagram of a modified example of the drive means for advancing and retreating the connection plug of the tool adapter with a built-in mechanism. 1: Shaft portion 2: Flange portion 3: Tapered shank 4: Shaft pin 5.21: Rolling bearing 6: Annular groove 7: Threaded hole 8: Small diameter housing portion

Claims (1)

[Claims] A fixed part which is adapted to be coupled to the fixed side of a machine tool etc. in a manner that allows it to engage and disengage freely, and a fixed part which is rotatably supported within the fixed part,
The part attached to the main shaft is rotatably supported within a rotating part formed at the protruding rear end and a fixed part, and is connected to the rotating part via a friction transmission planetary speed increasing mechanism, and the tool is gripped at the tip. A rotation detecting device is interposed between the tool gripping portion in which the part is formed, the fixed portion and the tool gripping portion, and detects the rotation state of the tool gripping portion, and a detection signal from the rotation detection device is transmitted to an external control device. A tool adapter with a built-in speed increasing mechanism, consisting of a connector to which an external conductor can be detachably connected to a rotation detecting device to send the data to the rotation detecting device.