JPH05337771A - Tool mounting device - Google Patents

Abstract

PURPOSE:To enhance the reproducibility in tool replacement. i.e., the repetitive accuracy, and perform high precision grinding work by using a second tool holder consisting of a plane gear coupling which has a high auto-centripetal property and high rigidity. CONSTITUTION:The first tool holder includes fundamentally a tapered shank to be fitted in a taper hole 3 and a key seat in which a drive key 6 is seated. The second tool holder 30 comprises a pull-stud 33, a guide 34 in the form of truncated cone to be loosely fitted on the coupling shaft 32 of the holder body 31 so as to guide the holder body 31 along the taper hole 3, and a coupling member 37 furnished with coupling teeth 38 secured to the holder body 31 and meshing with coupling teeth 9 and a seal ring 39 to seal the opening of a ring- shaped cover 12. For standard processing, a tool 27 is fitted on the spindle 2 using the first tool holder, while is fitted using the second tool holder 30 for precision machining.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tool inserting device for automatically inserting a tool into a spindle of a machine tool having a tool automatic changing device such as a machining center.

[0002]

2. Description of the Related Art Generally, a tool insertion device for a machine tool is provided with a tapered hole at a front end portion of a machine spindle, and a clamp mechanism is provided in a hollow hole which is continuous with the inside of the tapered hole and extends in the axial direction. On the other hand, various tools are attached to a tool holder having a taper shank that closely fits into the taper hole, the taper shank is fitted into the taper hole, and is pulled inward by the clamp mechanism to be inserted. I am supposed to wear it.

[0003]

In the above-mentioned conventional tool insertion device, since the taper shank of the tool holder is only in contact with the inner surface of the taper hole, not only is there a problem in rigidity, but also the tool. When the replacement is repeated, the spindle axis and the tool holder axis do not exactly coincide with each other, and there is a problem that the reproducibility of the tool replacement is deteriorated, which is unsuitable for high-precision machining and grinding.

The present invention has been made in view of the above circumstances, and employs a surface gear coupling (for example, a hearth coupling, a curbic coupling) having a high automatic centripetal property and a high rigidity as an insertion mechanism. This improves the reproducibility of tool change and enables high-precision machining and high-precision grinding.On the other hand, in the case of normal cutting, the insertion mechanism by fitting the taper shank and taper hole is selected as in the past. An object of the present invention is to provide a tool insertion device that can be freely exchanged.

[0005]

In order to achieve the above object, the tool inserting device of the present invention is provided with a taper hole at the front end portion of the machine main shaft, which is continuous with the inner side of the taper hole and which is axial direction. Has a clamp mechanism housed in a hollow hole extending to the front end surface of the main shaft, a drive key, a coupling member provided with coupling teeth of a surface gear coupling, and an outer peripheral portion of the coupling teeth. An annular cover for covering is fixedly attached, while the taper hole has a first insertion mechanism with a different insertion mechanism.
A tool holder and a second tool holder are selectively and interchangeably inserted, and the first tool holder has a taper shank that closely fits the taper hole and a puller that engages the clamp mechanism. The second tool holder includes a stud, a key groove that engages with the drive key, and a sealing ring body that seals the opening of the annular cover. The second tool holder includes a pull stud that engages with the clamp mechanism and a holder body. A guide body that is loosely fitted and guides the holder main body along the tapered hole; and a sealing ring body that is fixed to the holder main body and seals the coupling tooth that meshes with the coupling tooth and the opening of the annular cover. And a coupling member provided.

The pull stud of the second tool holder is movably connected to the holder body so that the coupling member is not affected by bending, prying, etc., which acts when the pull stud is pulled. Is desirable.

[0007]

With the above construction, the tool is inserted into the spindle using the first tool holder for standard machining, and the tool is inserted into the spindle using the second tool holder for high-precision cutting and grinding. To wear. This achieves a rational and economically advantageous tool insertion.

[0008]

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

FIG. 1 shows a tool inserting apparatus according to the present invention in which a first tool holder is inserted, and FIG. 4 shows a tool inserting apparatus according to the present invention in which a second tool holder is inserted.

1 is a spindle head of a machine tool equipped with an automatic tool changer such as a machining center, 2 is a spindle, and a spindle head 1
Is rotatably supported via a bearing (not shown), and is rotationally driven by a spindle motor (not shown) built in the spindle head 1. Reference numeral 3 denotes a tapered hole provided at the front end portion of the main shaft 2, and a clamp mechanism 5 is provided in a hollow hole 4 which is continuous with the inside of the tapered hole 3 and extends in the axial direction. 6 is a drive key, which is fixed to the front end portion of the main spindle 2 with a bolt 7.
It projects in parallel with the axis of.

Reference numeral 8 is a coupling member which constitutes a surface gear coupling, and has ring-shaped coupling teeth 9 on one side and a short cylindrical portion 10 fitted on the main shaft 2 on the other side. There is. A keyway 11 (see FIGS. 2 and 3) is provided on the inner bottom of the cylindrical portion 10. Further, an annular cover 12 that covers the outer peripheral portion of the coupling tooth 9 and extends a fixed length in the axial direction is fixed to the coupling member 8. The coupling tooth 9 is most preferably a known Haas coupling or curbic coupling tooth profile having a high self-centering property. The coupling member 8 has a cylindrical portion 10
Is attached to the front end of the main shaft 2, and four set bolts 13 are screwed to a nut 14 embedded in the front end of the main shaft 2 to be fixed to the main shaft 2, and the coupling teeth 9 are concentric with the main shaft 2. On the other hand, a drive key 15 fixedly provided on the front end surface of the main shaft 2 by a bolt 16 engages with the key groove 11 and is rotationally driven by the main shaft 2 via the drive key 15. ..

Reference numeral 20 denotes a first tool holder, which basically has the same structure as the tool holder in the conventional tool insertion device, and a taper shank 22 which is closely fitted to the taper hole 3 on one side of the holder body 21. And a pull stud 23 that engages with the clamp mechanism 5 is provided at the end of the tapered shank 22. Further, a key groove 24 that engages with the drive key 6 is provided in the holder body 21, and a sealing ring body 25 that seals the opening of the annular cover 12 of the coupling member 8 at the time of insertion is further provided with a sealing ring body 25. Is stuck to. The seal ring 2 is provided on the outer peripheral portion of the sealing ring body 25.
6 is fitted. 27 is a tool attached to the first tool holder 20.

Reference numeral 30 denotes a second tool holder. As shown in FIG. 4, a connecting shaft 32 is fixedly projectingly provided on one side of the holder main body 31, and an end portion of the connecting shaft 32 is engaged with the clamp mechanism 5. Pull studs 33 are provided. Further, a truncated cone-shaped guide body 34 is attached to the connecting shaft 32 in a loosely fitted state. The guide body 34 only guides the holder main body 31 along the taper hole 3 at the time of insertion, and the guide body 34 closely fits into the taper hole 3 like the taper shank 22 of the first tool holder 20 so that the positioning action with respect to the main shaft 2 is prevented. I don't have it. Therefore, the guide body 34 is loosely fitted to the connecting shaft 32, is urged toward the pull stud 33 by the spring 35 fitted to the connecting shaft 32, and is a stopper fitted to the intermediate portion of the connecting shaft 32. Axial movement is restricted by 36. On the other hand, on the outer peripheral portion of the holder main body 31, a coupling member 37 that cooperates with the coupling member 8 to form a surface gear coupling is integrally provided. Coupling member 3
7 is a coupling tooth 38 that meshes with the coupling tooth 9.
And a sealing ring body 39 for sealing the opening of the annular cover 12, and a sealing 40 is fitted around the outer periphery of the sealing ring body 39. Furthermore, the holder body 31 is provided with a recess 41 so that the drive key 6 does not interfere with the insertion of the holder body 31.

In the tool inserting apparatus according to the present invention having the above-described structure, in the case of performing normal machining, as shown in FIG. 1, the tool inserting apparatus is inserted into the spindle 2 by using the first tool holder 20 and driven. The tool 27 attached to the first tool holder 20 is rotated via the key 6. At this time, the sealing ring body 25 seals the opening of the annular cover 12 to prevent chips and other foreign matter from adhering to the coupling teeth 9.

On the other hand, when performing highly accurate cutting or grinding, the tool 27 is attached to the spindle 2 by using the second tool holder 30 as shown in FIG. At this time, the pulling operation of the pull stud 33 by the clamp mechanism 5 causes the coupling teeth 9 and the coupling teeth 38 to mesh with each other, and the automatic centering action positions the second tool holder 30 coaxially with the axis of the spindle 2. At the same time, it is firmly clamped to the main shaft 2 via the meshed coupling teeth 9 and 38,
High rigidity can be obtained. Therefore, chattering can be effectively prevented from occurring during machining with the tool 27, and highly precise machining can be performed. In this case also, the sealing ring body 39
The opening of the annular cover 12 is hermetically sealed to prevent chips and other foreign matter from entering the meshing portions of the coupling teeth 9 and the coupling teeth 38.

FIG. 5 shows the connecting shaft 32 of the second tool holder 30.
In the figure, an example is shown in which the pull stud 33 formed separately is movably connected. The connecting shaft 32 is formed to be short, and a supporting cylinder 42 provided with a locking step portion 43 at its end is connected and fixed. On the other hand, the pull stud 32 has a hole 44 in the support cylinder 42.
The head portion 45 provided at the inner end of the head portion 45 is locked to the step portion 43 to be movably connected, and the head portion 45 is attached to the support cylinder 42 by the spring 46. It is urged to abut against 43.

If such a structure is adopted, the coupling member 37 of the second tool holder 30 is not affected by bending or prying when the pull stud 33 is engaged with the clamp mechanism 5 and pulled, so that the engagement is achieved. The automatic centripetal action of both coupling teeth 9 and 38 is further ensured, and the reproducibility at the time of tool change is enhanced.

In FIG. 6, the coupling member 8 fixed to the front end of the main shaft 2 is provided with an inlet portion 3a of the tapered hole, and the inlet portion 3a and the tapered hole 3 provided at the front end of the main spindle 2 are integrally formed. Tapered gauge line GL processed and shown in phantom
Shows an example in which it is located on the same plane as the tooth crest surface of the coupling tooth 9.

If such a structure is adopted, the axial length of the entire apparatus can be reduced to increase the rigidity, and at the same time, the concentricity between the coupling teeth 9 and the spindle 2 is increased, and the reproducibility of tool exchange is improved. Is further improved.

FIG. 7 shows an example in which the coupling member 8 fixed to the front end of the main shaft 2 is machined integrally with the main shaft 2. With such a configuration, it is possible to further reduce the axial length of the entire device.

[0021]

As described above, according to the present invention,
Selectively replace the first tool holder by fitting the taper shank and the taper hole and the second tool holder by the face gear coupling with high automatic centering and high rigidity to the taper hole provided at the front end of the spindle. Since a tool insertion mechanism that can be inserted is used, the standard tool is used to insert the tool into the spindle using the first tool holder, and the second tool holder is used for high-precision cutting and grinding. By inserting into the main shaft, a rational and economically advantageous tool insertion can be achieved.

Especially when the second tool holder is used,
Reproducibility of tool change, that is, repeatability is improved,
Since high-precision grinding is possible, if the tool insertion device of the present invention is used in a machining center, there is a great advantage that it can also be used as a grinding center.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view of an essential part showing a tool inserting device of the present invention in which a first tool holder is inserted.

FIG. 2 is a sectional view taken along line 2-2 of FIG.

3 is a sectional view taken along line 3-3 of FIG.

FIG. 4 is a longitudinal sectional view of a main part showing a tool inserting device of the present invention in which a second tool holder is inserted and attached.

FIG. 5 is a partially cutaway vertical sectional view of a main part showing another embodiment of the second tool holder.

FIG. 6 is a longitudinal sectional view showing another embodiment of the coupling member fixed to the front end portion of the main shaft.

FIG. 7 is a view similar to FIG. 6 and is a vertical sectional view showing still another embodiment.

[Explanation of symbols]

 1 Spindle Head 2 Spindle 3 Tapered Hole 4 Hollow Hole 5 Clamp Mechanism 6 Drive Key 8 Coupling Member 9 Coupling Tooth 12 Annular Cover 20 1st Tool Holder 21 Holder Body 22 Taper Shank 23 Pull Stud 25 Sealing Ring Body 27 Tool 30th 2 Tool holder 31 Holder body 32 Connecting shaft 33 Pull stud 34 Frustum-shaped guide body 37 Coupling member 38 Coupling tooth 39 Sealing ring body

Claims (4)

[Claims] 1. A taper hole is provided in a front end portion of a machine spindle, and a clamp mechanism is provided in a hollow hole which is continuous with the inner side of the taper hole and extends in an axial direction. A drive key and a coupling member provided with coupling teeth of a surface gear coupling,
An annular cover for covering the outer peripheral portion of the coupling tooth is fixed, and on the other hand, a first tool holder and a second tool holder having different insertion mechanisms are selectively and interchangeably inserted into the tapered hole. The first tool holder includes a taper shank that closely fits into the taper hole, a pull stud that engages with the clamp mechanism, a key groove that engages with the drive key, and the annular cover. The second tool holder includes a pull stud that engages with the clamp mechanism, and a guide ring that loosely fits into the holder body and guides the holder body along the tapered hole. A body, and a coupling member fixed to the holder body and provided with a coupling tooth that meshes with the coupling tooth and a sealing ring body that seals the opening of the annular cover. Tool insertion device there. 2. The pull stud of the second tool holder comprises:
The tool insertion device according to claim 1, wherein the tool insertion device is movably connected to the holder body and is configured so that the coupling member is not affected by bending, prying, or the like that acts when the pull stud is pulled. 3. The coupling member fixed to the front end surface of the main shaft, wherein an inlet portion of the tapered hole is machined integrally with a tapered hole portion provided in the main shaft. Tool insertion device. 4. The tool insertion device according to claim 1, wherein the coupling member fixed to the front end surface of the main shaft is machined integrally with the main shaft.