JPH0132003B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a tool holder used in a machine tool such as a milling machine, a boring machine, or a machining center. This invention relates to a tool holder that enables accurate and easy operation from outside the tool holder.

[Prior art]

In machine tools such as milling machines, boring machines, and machining centers, tools are attached to the main shaft of the machine tool via tool holders. In this case, it is necessary to adjust the attachment length of the tool to the tool holder.Especially in the case of a multi-spindle machine tool that has multiple spindles on the same spindle head, the length of each tool holder attached to each spindle must be adjusted. Differences in tool attachment length directly result in machining errors, so it is necessary to make the tool attachment lengths to each tool holder the same.

However, the means for adjusting the installation length of the tool in a tool holder, which is commonly used in the past, is to rotate a reference block for positioning the tool length provided at the back of the tool insertion hole of the holder body using a screwdriver or the like. I was beginning to adjust my position. Therefore, in order to adjust the position of the reference block, the tool must be removed from the holder body each time, and the adjustment of the tool installation length requires a great deal of effort.

In addition, adjustment means that allows the tool attachment length to be adjusted from outside the tool holder is also used in some cases. However, this adjustment means
As shown in FIG. 4, an adapter insertion hole 2 is provided in the holder body 1, a screw 4 is cut in the front part of the adapter 3 which is movably inserted into the adapter insertion hole 2, and a ring 5 is screwed into the screw 4. The adapter 3 is moved in and out of the holder main body 1 by rotating the adapter 3, thereby adjusting the attachment length of the tool T to the tool holder. Therefore, a special adapter had to be prepared separately, and the centering of the tool T could not be performed accurately due to machining errors in providing the adapter insertion hole 2 and the clearance required for inserting the adapter. Furthermore, since the adapter is fixed with a side lock, accurate centering of the tool T is more difficult and highly accurate machining is impossible. Furthermore, since the length of the tool is adjusted using the pitch of the screw, it is difficult to make fine adjustments.

[Purpose of the invention]

The first object of the present invention is to be able to make fine adjustments from the outside without removing the tool from the tool holder, especially in multi-axis machine tools, when setting the tools on each axis with high precision by eliminating mutual differences in installation length. The objective is to provide a tool holder designed to A second object of the present invention is to provide a tool holder that does not require special skills or proficiency when setting a tool to a predetermined length with high precision. A third object of the present invention is to provide a tool holder that allows accurate centering of the tool during tool attachment, thereby enabling highly accurate machining. Furthermore, a fourth object of the present invention is to provide a tool holder that allows adjustment of the attachment length of the tool without separately preparing a special adapter.

[Structure of the invention]

The present invention provides a tool holder in which the attachment length of a tool can be adjusted, including a holder body having a tool insertion hole in the longitudinal direction at the center and an insertion hole in the radial direction, and an insertion hole in the holder body in the radial direction. A reference block for positioning the tool length that is movably inserted into the tool insertion hole of the holder body, and a rotatable and eccentric part is provided in each of the insertion holes of the holder body and the reference block. The holder is constructed of an eccentric shaft that is fitted in correspondence with the reference block and that has at least one end provided with an operating section that can be adjusted from the outside of the holder main body.

[Explanation of Examples]

1 to 3 show one embodiment of the present invention, in which FIG. 1 is a longitudinal cross-sectional view of a tool holder, FIG. 2 is a view taken in the direction of arrow A in FIG. 1, and FIG. FIG.

In these drawings, reference numeral 10 denotes a holder main body of the tool holder, which is provided through a tool insertion hole 11 in the central longitudinal direction, and has a tool insertion hole in the lower radial direction of a shank portion 12 attached to a main shaft (not shown). An insertion hole 13 is provided that intersects and penetrates the hole 11 at right angles. 14 is a pull stud screwed into the tool insertion hole 11 at the upper end of the holder body 10. A tool insertion hole 11 is provided at the lower end of the holder body 10.
a conical slot member 15a that fits into the opening of the
A collection chuck 15 is formed which includes a tightening tool 15b that is screwed onto the outer circumferential threaded portion of the lower end of the holder body 10. Reference numeral 16 denotes a gripping groove ring fitted on the outer periphery of the holder body 10 below the shank portion 12, and is gripped by a tool exchange arm when automatically exchanging tools in a machining center or the like.
Reference numeral 17 denotes a keyway that engages with the key of the tool exchange arm, the key of the main shaft, etc. to adjust the phase of the tool T, and is formed to coincide with one opening of the insertion hole 13.

Reference numeral 20 denotes a reference block, which is movably fitted into the back of the tool insertion hole 11 of the holder body 10. This reference block 20 is provided with an insertion hole 21 corresponding to the insertion hole 13 of the holder main body 10 in the radial direction of the body, and has an upper portion locked with one end of a tension spring 22 so as to be constantly pulled upward.
The other end of the tension spring 22 is engaged with the lower end of a locking rod 24 pinned to an adjustment screw 23, and the tension is adjusted by moving the adjustment screw 23.

On the other hand, a block body 25 having a ball 26 provided on the surface against which the end of the tool T comes into contact is screwed onto the lower end of the reference block 20. By adjusting the screwing amount of this block body 25, the tool installation length can be roughly adjusted. In addition, the reason why the ball 26 is provided on the contact surface with the tool T is to improve the slippage of the end of the tool.
This is to prevent the tool T from bending or swinging when tightening.

30 is an eccentric shaft with an eccentric portion 31 approximately in the center;
Insert the eccentric part 31 into the insertion hole 21 of the reference block 20,
Further, both side portions are rotatably fitted into the insertion holes 13 of the holder main body 10. An operating portion 32 consisting of a wrench fitting hole located on the outer circumference of the holder body 10 is provided at one end of the eccentric shaft 30, and the other end is in contact with a receiving member 33 via a ball 34. 35 is eccentric shaft 3
This is a ring to prevent the screw 0 from protruding from the insertion hole 13, and is fixed with a screw 36.
As mentioned above, since the reference block 20 is pulled upwardly by the tension spring 22,
The insertion hole 21 is in pressure contact with the lower part of the eccentric portion 31 of the eccentric shaft 30.

In this embodiment, the relationship between the amount of rotation (rotation angle) of the eccentric shaft 30 and the amount of adjustment of the attachment length of the tool T is as shown in the following table.

Rotation angle of eccentric shaft (°) Tool length adjustment amount (μ) 0 0 30 6.7 45 15 60 25 90 50 120 56.7 135 65 150 75 180 100 In this example, the tool installation length is adjusted by the eccentric shaft 30. Although the relationship is as described above because of the fine adjustment of the height, it is not necessarily limited to the above relationship.

In the tool holder constructed as described above, the attachment length of the tool is adjusted as follows.

First, adjust the screwing amount of the block body 25 of the reference block 20 according to the type of tool to be installed.
Make rough adjustments. Next, the tool T is attached to the holder body 1.
0 into the tool insertion hole 11, and while pressing the tool T against the abutment surface of the block body 25, the collector chuck 15 is tightened to the extent that the tool T moves when the eccentric shaft 30 is rotated. Next, a wrench or the like is fitted into the operating portion 32 at one end of the eccentric shaft 30, the eccentric shaft 30 is rotated, and the amount of protrusion of the tool T from the holder body 10 is adjusted to a set length using a dial gauge or the like. . After adjustment, the collector chuck 15 is firmly tightened to firmly fix the tool T, making it ready for cutting. In the case of a multi-axis machine tool, the above adjustment work is performed for each axis in sequence to eliminate the difference in installation length between tools on each axis.

In addition, in the present invention, the insertion hole 13 of the holder body is not a through-hole type, but is formed only between the tool insertion hole 11 and one side circumferential surface of the holder body 10, and the eccentric shaft 3
0 may be so-called cantilevered. In addition, the eccentric shaft 3
The operating portion 32 of 0 can also be made to protrude from the circumferential surface of the holder main body 10, and its shape may also be such that it can be rotated by a screwdriver, a spanner, or the like. Depending on the type of tool holder, it is also possible to provide operating sections 32 at both ends of the eccentric shaft 30 so that the rotation can be operated from either side.

Furthermore, the reference block 20 does not necessarily need to be provided with the block body 25 at its lower end, and the lower end of the reference block 20 may be used as a direct contact surface with the tool T. The ball 26 on the contact surface may also be omitted in some cases. Furthermore, the form of the tool holder is not limited to the above-mentioned pull stud and collect chuck forms.

That is, in addition to the embodiments described above, the present invention includes
This includes various modifications.

〔Effect of the invention〕

As described above, according to the present invention, when installing tools for each axis in a multi-axis machine tool, fine adjustments can be easily made from outside the tool holder without removing the tool from the tool holder, and the tool length for each axis can be easily adjusted. It is possible to eliminate mutual differences and set with high precision. Moreover, no special skill or skill is required to set the tool to a predetermined length with high precision.
Further, there is no need to separately prepare a special adapter or the like, and the centering of the tool can be performed accurately when the tool is attached, making it possible to perform highly accurate machining.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view of one embodiment of the present invention, Fig. 2 is a view taken in the direction of arrow A in Fig. 1, Fig. 3 is an overall perspective view of the eccentric shaft, and Fig. 4 is a sectional view of essential parts of a conventional example. show. 10... Holder body, 11... Tool insertion hole, 1
3...Insertion hole, 20...Reference block, 21...
Insertion hole, 25...Block body, 30...Eccentric shaft,
31... Eccentric part, 32... Operation part.

Claims (1)

[Claims] 1. A tool holder with adjustable tool installation length, which includes a holder body with a tool insertion hole in the center longitudinal direction and an insertion hole in the radial direction, and a tool holder with an insertion hole in the radial direction, A reference block for positioning the tool length that is movably inserted into the insertion hole, and a reference block that is rotatably inserted into the respective insertion holes of the holder body and the reference block, with the eccentric portion corresponding to the reference block, and at least one end of the reference block. A tool holder consisting of an eccentric shaft with an operating part that can be rotated from the outside of the holder body.