JPH0451923Y2 - - Google Patents

Description

[Detailed Description of the Invention] "Purpose of the Invention" (Field of Industrial Application) The present invention relates to a tool clamping device for a machine tool having a main shaft with a taper.

(Prior Art) Conventionally, for example, in machine tools such as milling machines or boring machines having a main spindle with a taper, a threaded portion provided on the tool shank side has been used as a means for attaching the tool shank to the main spindle. I was doing it.

For example, a tool mounting means used in a machining center or the like as shown in FIG. 12 has a pull stud bolt 105 attached to a threaded portion provided on a taper shank 103 holding a tool 101. The tool is attached by pulling up the shaft 107 that engages with the pull stud bolt 105 using hydraulic pressure or the like, and fitting the taper shank 103 onto a tapered surface provided on the main shaft 109.

In addition, the tool attachment means used in a general-purpose milling cutter or the like shown in FIG.
The tool was attached by fitting 03 onto the main shaft 109.

(Problems to be Solved by the Invention) However, such conventional tool mounting means is equipped with some sort of clamping mechanism inside the spindle on the spindle side to pull up the tool shank.
There were problems in that the inside of the spindle became more complex, the number of parts and the number of machining steps increased, and the cost increased as the equipment became larger.

This invention has been devised in view of the above-mentioned problems, and aims to provide a tool clamping device that does not have a tool clamping mechanism inside the spindle side.

[Structure of the invention] (Means for solving the problems) In view of the conventional problems as mentioned above, the present invention has the following features:
A V-shaped groove is provided on the outer circumferential surface of a flange portion of a tool shank, which is provided with a tapered surface that can be freely engaged and detached from the engagement hole of a main shaft having a tapered engagement hole. A key groove that can be freely engaged and detached from the key provided therein is provided in the flange part, and the key groove is communicated with the groove part, and a claw part that can freely engage with the groove part after passing through the key groove is radially inward. A protruding annular tool clamp cap is rotatably attached to the end face of the main spindle via a plurality of fastening bolts screwed into a plurality of screw holes provided on the end face of the main spindle, and each of the above-mentioned The tool clamp cap is provided with a flange against which the head of each fastening bolt comes into contact and presses the tool shank in the direction of pulling out the tool shank when the fastening bolts are loosened.

(Example) Hereinafter, an example of the present invention will be described in detail based on the drawings.

Referring to FIGS. 6 to 11, FIGS. 6 and 7 show the tool in a clamped state, and a main shaft 5 rotatably supported on the machining head 1 via a bearing 3 is provided. .

On the lower end surface of this main shaft 5 (lower in FIG. 6),
As shown in FIGS. 8 and 9, a plurality of keys 7 are attached, and these keys 7 serve to prevent a tool shank 9, which will be described later, from rotating.

Further, a plurality of screw holes 11 are provided on the lower end surface, and an engagement hole 15 with a tapered surface 13 is provided inside the main shaft 5 .

On the other hand, referring to FIGS. 10 and 11, this tool shank 9 does not have a special structure but is commonly used, and has a taper that engages with a tapered surface 13 provided inside the main shaft 5. A surface 17 is provided. Furthermore, a screw hole 21 for screwing the pull bolt 19 is provided at the upper end (upper side in FIG. 6), and a V-shaped groove 23 is provided around the outer circumferential surface of the flange portion provided near the lower part. A plurality of key grooves 25 are provided to fit with the keys 7 provided in the key 5.

A drilling tool 27 is attached to the tool shank 9, and in order to secure the tool shank 9 to the main shaft 5, a tool clamp cap 31, which is a tool clamping device 29, is locked to the main shaft 5 by a fastening bolt 33.

This tool clamp device 29 will be explained in more detail. Referring to FIGS. 1 to 5, the tool clamp cap 31 of the tool clamp device 29 is provided with a plurality of elongated holes 35 facing each other near the outer periphery.
Further, a plurality of claws 37 are provided on the inner periphery and protrude in the radial direction, and the tips of the claws 37 are V-shaped in order to fit into the V-shaped groove 23 provided in the tool shank 9. The width is configured to be slightly smaller than the width of the key 7.

The main shaft 5 is provided with an escape groove 39 within a range that does not interfere with the plurality of keys 7 provided on the main shaft 5, and a collar 41 is provided around the side opposite to the main shaft (lower side in Fig. 1) in the inner diameter direction. ing. This collar 41 is provided with an escape hole 43 at a position corresponding to the starting point of the elongated hole 35 so that the head of a tightening bolt 33 for fastening the tool clamp cap 31 to the main shaft 5 does not interfere with the head.

With the above configuration, when attaching the tool shank 9 to the main spindle 5, the keyway 2 provided in the tool shank 9
5, the key 7 provided on the spindle 5 side, and the claw portion 37 provided on the clamp cap 31 are aligned on the same line, and the tool shank 9 is inserted.

In this case, the fastening bolt 33 is slightly loosened so that the main shaft 5 and the clamp cap 31 can rotate freely.

After inserting tool shank 9, clamp cap 3
1, the claw part 37 provided on the clamp cap 31 is inserted into the groove part 23 provided in the tool shank 9, and the taper of the tool shank 79 is inserted into the tapered surface 13 provided on the main shaft 5 by tightening the fastening bolt 33. The surface 17 can be inserted and fixed.

When removing the tool shank 9 from the main shaft 5, it can be removed by performing the upstream operation in reverse. That is, when the tightening bolt 33 is loosened, the head of the tightening bolt 33 comes into contact with the collar 41 provided on the clamp cap 31, and by loosening the tightening bolt 33, the clamp cap is pushed downward, and at the same time, the tool shank 9 The tapered surface 17 is also removed from the main shaft 5. In this state, the tool shank 9 can be removed by rotating the clamp cap 31 and aligning the claw portion 37 with the keyway 25 of the tool shank 9.

As described above, since the tool clamping device 29 is not provided inside the main spindle 5, the inside of the main spindle has a simple structure, and the number of machining operations can be reduced and compactness can be achieved. Further, the tool can be clamped regardless of the presence or absence of the pull bolt 19 on the tool shank side, and it is possible to use common tools.

Note that, without being limited to the above-mentioned embodiments,
Of course, various changes can be made without departing from the gist of the present invention.

[Effects of the Invention] As can be understood from the above description of the embodiments, the present invention has a tapered surface 17 that can be freely engaged with and disengaged from the engagement hole 15 of the main shaft 5 provided with the tapered engagement hole 15. A V-shaped groove 23 is provided on the outer circumferential surface of the flange portion of the tool shank 9 comprising:
A key groove 25 that can be freely engaged and detached from the key 7 provided on the end surface of the main shaft 5 is provided in the flange portion, and the key groove 25 is communicated with the groove portion 23. An annular tool clamp cap 31 having a claw portion 37 protruding radially inward and capable of engaging with the main shaft 5 is inserted through a plurality of fastening bolts 33 screwed into a plurality of screw holes 11 provided on the end surface of the main shaft 5. A flange 41 is rotatably mounted on the end surface of the main shaft 5, and the head of each fastening bolt 33 contacts and presses the tool shank 9 in a direction when loosening the fastening of the fastening bolt 33. This is provided in the tool clamp cap 31.

As is clear from the above configuration, in the present invention, the tool clamp cap 31 for fixing the tool shank 9 to the main shaft 5 includes a plurality of fastening bolts 3.
3, it is rotatably attached to the end face of the main shaft 5. When each of the fastening bolts 33 is loosened, the head of the fastening bolt 33 contacts the collar 41 and presses the tool clamp cap 31 in the direction of removing the tool shank 9.

Therefore, according to the present invention, a plurality of screw holes 11 for screwing a plurality of fastening bolts 33 are provided in the main shaft 5.
The tool clamp cap 31 can be attached to the end face of the spindle 5 even with a simple structure in which it is only provided on the end face of the main shaft 5. In other words, it is easy to attach to the end face of an existing spindle.

Also, when the fastening bolt 33 for attaching the tool clamp cap 31 to the end face of the main shaft 5 is loosened,
The head comes into contact with the collar 41 of the tool clamp cap 31 and presses the tool shank 9 in the direction of pulling it out from the engagement hole 15 of the main shaft 5. Therefore, by loosening and pressing each fastening bolt 33 individually, the main shaft 5 Since the contact between the tapered surface 13 of the engagement hole 15 and the tapered surface of the tool shank 9 is broken part by part and then pried open, the tool shank 9 can be easily removed.

[Brief explanation of the drawing]

1 to 5 show an embodiment of the tool clamping device according to the present invention, in which FIG. 1 is a longitudinal sectional view, and FIG.
The figure is a plan view of Fig. 1, Figs. 3 to 5 show the clamp cap alone, Fig. 3 is a plan view taken in the direction of the arrow in Fig. 4, and Fig. 4 is a plan view taken along the - line in Fig. 3. The sectional view and FIG. 5 are plan views taken in the direction of arrow V in FIG. 4. 6 and 7 show an embodiment in which a tool shank embodying the present invention is attached to a main shaft, FIG. 6 is a longitudinal sectional view, and FIG. 7 is a plan view of FIG. 6, and FIGS. FIG. 9 shows the end of the main shaft, FIG. 8 is a longitudinal sectional view, and FIG. 9 is a plan view of FIG. 8. 10 and 11 show the tool shank, with FIG. 10 being a side view and FIG. 11 being a plan view of FIG. 10. FIG. 12 and FIG. 13 show a conventional example, and each is a vertical sectional view. Explanation of symbols representing main parts of the drawing, 5...
Spindle, 9... Tool shank, 23... Groove, 29
...Tool clamp device, 31...Tool clamp cap, 37...Claw portion.

Claims (1)

[Scope of utility model registration request] A V is formed on the outer circumferential surface of the flange portion of the tool shank 9, which is provided with a tapered surface 17 that can be freely engaged with and disengaged from the engagement hole 15 of the main shaft 5, which is provided with a tapered engagement hole 15.
A key groove 23 is provided in the flange portion, and a key groove 25 that can be freely engaged and detached from the key 7 provided on the end surface of the main shaft 5 is provided in the flange portion.
3, an annular tool clamp cap 31 having a claw portion 37 protruding radially inward and capable of passing through the keyway 25 and freely engaging with the groove portion 23;
, a plurality of screw holes 11 provided on the end surface of the main shaft 5
It is rotatably attached to the end face of the main shaft 5 via a plurality of fastening bolts 33 screwed into the main shaft 5, and when loosening the tightening of each fastening bolt 33, the head of each fastening bolt 33 comes into contact with the end face of the main shaft 5. A tool clamp device characterized in that the tool clamp cap 31 is provided with a collar 41 that presses the tool shank 9 in a direction to pull it out.