JPH0144246Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to a tool mounting device suitable as a tool mounting device for machining centers and the like.

(Prior Art) Conventionally, an apparatus of this type as shown in FIG. 1 has been known. That is, the taper shank portion 5 of the tool mounting shank 4 to which the tool 3 is attached is fitted into the tapered shank fitting hole 2 of the spindle 1, and this tapered shank portion 5 is inserted into the fitting hole 2.
Pull the large-diameter portion 6 at the rear end (right side in FIG. 1) rearward by the tool holder 7 so that it fits tightly into the tool holder.
It is known that the tool attachment shank 4 is attached to the spindle 1 by aligning the axis of the tool attachment shank 4 with that of the insertion hole 2.

(Disadvantages of the prior art) The conventional device has the following drawbacks. That is, by pulling the tapered shank part 5 backward and tightly fitting the tapered shank part 5 into the inner circumferential surface of the tapered fitting hole 2, the axis of the tapered shank part 5 is aligned with that of the fitting hole 2. In order to match the flange portion 8 of the tapered shank portion 5 to the front surface of the spindle 1, it was necessary to create a gap 9 therebetween. This is because the flange part 8 is
If it comes into contact with the front of the tool mounting shank 4,
This is because the spindle 1 receives the tensile force that pulls it backward through the flange portion 8', and the tapered shank portion 5 cannot be tightly fitted into the insertion hole 2. Therefore, because of the gap 9, that is, because the flange portion 8 cannot come into close contact with the spindle 1, the flange portion 8 tends to vibrate with respect to the axis, and as a result, there is a drawback that chatter vibration is likely to occur in the tool 3.

(Purpose of the invention) This invention was made in order to eliminate the above-mentioned drawbacks, and is a tool mounting method that allows the flange portion to come into contact with the front surface of the spindle and the tool mounting shank to tightly fit into the insertion hole. The purpose is to provide a device.

(Example) This invention will be explained below based on the example shown in FIGS. 2 and 3.

A spindle 13 is rotatably fitted into the spindle support 11 via a bearing 12, and a tapered shank portion 16 of a tool attachment shank 15 is fitted into a tapered shank fitting hole 14 formed in the spindle 13. A flange portion 17 is provided at the front of the shank portion 16, which comes into contact with the front surface of the spindle 13 when the shank portion 16 is inserted into the shank insertion hole 14, and the portion of the flange portion 17 facing the spindle 13 A recess 18 is formed in the spindle 13, and a detent key 19 that fits into the recess 18 is provided on the spindle 13. A tool 20 is detachably attached or fixed to the flange portion 17 as is known in the art. In addition, the shank insertion hole 14 and the shank part 1
6 is not limited to a tapered shape, but may be straight.

A recess 21 is formed in the shank portion 16 and opens toward the rear (rear refers to the right side in FIG. 2, and front refers to the left side in the same figure). An annular groove 22 having an arcuate cross section is formed, thereby forming an engaging edge 23 on the inner circumference of the recess 18 . A drawbar 24 whose front end 24a is inserted into the recess 21 is fitted into the spindle 13 so as to be able to move forward and backward with its axis aligned with that of the spindle 13, and the truncated conical front end of the drawbar 24 The portion 24a has 120 parts surrounding it as clearly shown in Figure 3.
Notch step portions 25 are formed at intervals, and a pressing member 2 is connected to each of these notch step portions 25 via a shaft 27.
6 are provided to be swingable in the radial direction of the drawbar 24, and these pressing members 26 have a substantially triangular shape as shown in FIG. 2, and their outer ends 28 pull the drawbar 24 rearward as described later. As a result, it enters the annular groove 22 and engages the engagement edge 23,
The shank portion 16 is elastically deformed and pressed against the inner peripheral surface of the shank insertion hole 14. The pressing member 26 is urged to rotate clockwise by an elastic spring 30 interposed between the inner surface of a spring fitting hole 29 formed therein and the bottom of the notch step 25, and A stopper 3 in the shape of a disc spring is attached to the front end portion 24a to prevent rotation beyond the set position due to the biasing force of 30.
It is made to correspond to 1. The pressing member 26 is configured to come into contact with the stopper 31 when the drawbar 24 protrudes forward, and in this state, the outer end 28 is prevented from hitting the shank portion 16 and does not completely enter into the drawbar 24. It is done like this. The drawbar 24
A sliding sleeve 32 is slidably fitted into the housing, and this sliding sleeve 32 is biased to protrude forward by a spring 33, and does not protrude beyond the set position due to the biasing force of the spring 33. It has a retaining edge 34 that comes into contact with an annular step 35 formed on the spindle 13. And drawbar 2
4 retreats, the pressing member 26 presses the sliding sleeve 3
2 and rotated counterclockwise into the annular groove 2.
It is designed to fit into 2. A male threaded portion 36 is provided at the rear end of the drawbar 24, and a rotating body 38 having a threaded hole 37 is screwed into the male threaded portion 36, and this rotating body 38 is connected to the spindle 13 through a bearing 39. It is provided so that it can be rotated freely. By rotating the rotating body 38 with such a structure, the drawbar 24, which is designed not to rotate relative to the spindle 13, can be advanced or retreated. Note that the mechanism for advancing and retracting the drawbar 24 is not limited to the one in the embodiment; for example, a spring biases the drawbar 24 backward, and when the drawbar 24 is projected forward, it is pushed by hydraulic pressure. You can do it like this.

(Operation of the embodiment) Next, the operation of the embodiment will be explained. Note that the following actions are performed automatically or manually.

First, the drawbar 24 is projected forward to prevent the pressing member 26 from hitting the shank portion 16, and then the detent key 1 is inserted into the recess 18 so that the flange portion 17 hits the front surface of the spindle 13.
9 fits into the tool mounting shank 1.
The shank portion 16 of No. 5 is fitted into the shank fitting hole 14, and then the rotating body 38 is rotated to move the drawbar 24 backward. Then, the pressing member 26 comes into contact with the sliding sleeve 32 and is rotated counterclockwise, and its outer end 28 enters the annular groove 22 to elastically deform the shank portion 16 and push it into the shank insertion hole 14. Press it against the surrounding surface. In this way, the tool attachment shank 15 is attached to the spindle 13 with its axis aligned with that of the shank insertion hole 14.

(Effects of the invention) As described above, according to this invention, a flange part is provided at the front of the shank part, which comes into contact with the front surface of the spindle when the shank part is inserted into the shank fitting hole, and this shank part is provided with a flange part at the rear. A recess is formed that opens into the recess, and at least two pressing members that enter the recess are provided on the drawbar so as to be swingable within a virtual plane including the axis of the drawbar, and the pressing members are attached to the inner peripheral surface of the recess. By pressing, the shank part is elastically deformed and pressed against the inner circumferential surface of the shank insertion hole, so that chatter vibration does not occur in the tool mounting shank, and the axis of the tool mounting shank is not inserted into the shank. Coinciding with that of the hole, the tool mounting shank can be firmly attached to the spindle. Furthermore, by retracting the drawbar, the sliding sleeve urged forward by the spring can reliably raise the pressing member and press it against the inner circumferential surface of the recess.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of a conventional device, Fig. 2 is a longitudinal sectional view showing an embodiment of this invention, and Fig. 3 is a longitudinal sectional view of a conventional device.
FIG. 13...Spindle, 14...Shank fitting hole, 15...Tool mounting shank, 16...Shank portion, 17...Flange portion, 21...Recess, 26
...Press member.

Claims (1)

[Claims for Utility Model Registration] 1. In a tool mounting device in which a shank portion of a tool mounting shank is fitted and fixed into a shank insertion hole of a spindle, the shank portion is fitted into the shank insertion hole at the front of the shank portion. A flange portion that abuts the front surface of the spindle is provided, a recess that opens rearward is formed in the shank portion, and at least two pressing members that enter the recess are arranged on the drawbar in an imaginary plane including its axis. The drawbar is fitted into a spindle so as to be able to move forward and backward, and a sliding sleeve is slidably installed on the spindle and causes the drawbar to come into contact with a pressing member when it retreats. A tool mounting device in which the movable sleeve is urged forward by a spring. 2. The tool mounting device according to claim 1, wherein the shank portion is a tapered shank portion or a straight shank portion. 3. The tool mounting device according to claim 1, wherein the tool mounting shank and the tool are separate or integrated.