JP3244321B2 - Processing fluid supply device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a machining fluid supply device for effectively supplying a machining fluid to a machining point.

[0002]

2. Description of the Related Art In drilling of deep holes and processing of difficult-to-cut materials, tool breakage due to clogging of chips and tool wear increase due to processing heat. As a method of solving this, an oil hole is provided in a tool, and a machining fluid is directly supplied near a machining point. For example, the Journal of Precision Engineering (Vol. 58, No. 12, pages 13 to 16) discloses a method of supplying a working fluid to an oil hole of a tool with a working fluid supply mechanism rotatable with respect to a tool holder. It is described that there are provided a machining fluid and a machining fluid supply hole penetrating in the axial direction of the spindle to supply machining fluid from a shaft end opposite to a tool mounting side.

[0003]

However, the former, in which the machining fluid supply mechanism is provided on the tool holder, has been difficult to use at high speed because of the limitation of the bearing characteristics of the rotating mechanism and the wear of the seal. Further, when the tool is changed, it is necessary to change the connection of the machining fluid supply path, and the workability cannot be improved. ◆ On the other hand, in the latter case in which a machining fluid supply hole is provided in the axis of the spindle, it is not necessary to change the connection of the machining fluid supply path. However, as in the former, the rotating portion of the spindle and the stationary portion on the machining fluid supply side are connected. Due to the limited bearing characteristics of the rotating mechanism and wear of the seal, it has been difficult to use it at high speed rotation. In addition, a machine tool equipped with an automatic tool changer, such as a machining center, requires a drawing bolt mechanism for holding a tool at the axis of a spindle, which complicates the structure. ◆ The object of the present invention is to solve the above-mentioned problems of the prior art, to be able to be used even at high speed rotation, to have good workability,
Another object of the present invention is to provide a working fluid supply device that is easy to maintain.

[0004]

SUMMARY OF THE INVENTION The object of the present invention is to provide a tool holder or a tool having a substantially axial vertical hole which communicates from a circular groove provided on the outer periphery with a lateral hole provided in a substantially radial direction and opens at one end. A working fluid supply ring provided with a pair of working fluid supply flow paths that surround the annular groove at a small interval and that allow the working fluid to flow out in an annular or film shape toward substantially both side surfaces of the annular groove; It is solved by. Further, the problem can be solved even more effectively by providing the annular groove as a groove for gripping the tool of the automatic tool changer, or providing a means for separating and approaching the working fluid supply ring with respect to the tool holder or the tool.

[0005]

The working fluid is supplied as a pair of upper and lower annular and film-like flows to a tool holder or a tool separated from the working fluid supply ring with a minute gap therebetween. That is, they are non-contact, and no bearing and seal are used. Therefore, bearing characteristics are not limited and seal wear does not occur,
Can be used for high-speed rotation. Further, the working fluid is held by this annular / film-like flow, and even if the working fluid is supplied in a non-contact state, the fluid leakage is small. Further, since the working fluid supply ring is separated and approachable from the tool holder or the tool, the tool can be automatically changed as before.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a side view showing a configuration when the present invention is applied to a vertical machining center, and FIG.
FIG. 3 is a sectional view taken along line AA of FIG. 1 is a spindle head of the machining center, which is held in a column (not shown). Reference numeral 2 denotes a spindle, which is rotatably held by the spindle head 1. ◆ 10 is a tool holder, which is composed of the following parts. That is, a shank 11 is inserted into the tapered hole 3 provided in the spindle 2 and is fixed by a drawing bolt (not shown). An annular groove 12 for gripping a tool of the automatic tool changer is provided on the outer periphery of the shank 11 near the upper end tapered portion.
Further, a vertical hole 14 communicating with the horizontal hole 13 and penetrating the lower end in a substantially axial direction is formed. A stopper 15 having a through hole 16 is screwed into the vertical hole 14.
Reference numeral 17 denotes a collet which is inserted into a tapered hole 18 provided on the lower end side of the shank 11. Reference numeral 19 denotes a nut which is screwed to the lower end of the shank 11 to apply a tightening force to the collet 17. Reference numeral 20 denotes a drill, and the collet 1 is positioned in the axial direction by the stopper 15.
7 is held. The drill 20 has a through hole 21. For simplicity of illustration, the through hole 21 is shown as a straight hole in FIG. 3, but a helical hole equal to the twist angle of the drill 20 is actually provided.

Reference numeral 30 denotes a working fluid supply ring, a ring (right).
31 and the ring (right) 31 and the ring (left) 3
The ring (right) 31 and the ring (left) 32 are each held rotatably around a shaft 33 fixed to the spindle head 1. The working fluid supply ring 30 is composed of the following parts. That is, 34 is a centering, and the upper and lower end surfaces 35 and 36 on the inner peripheral side form a tapered surface having an inclination equal to the side surfaces 12 a and 12 b of the annular groove 12, and minute gaps 37 and 38 are separated from the annular groove 12. And it is arrange | positioned so that the cross section may form the trapezoid-shaped annular space 39 between the bottom surfaces of the annular groove 12 and. In this embodiment, the side surface 12a and the side surface 12b are vertically symmetric with respect to the center of the annular groove 12. Reference numeral 40 denotes a blind hole provided in the radial direction from the outer peripheral surface 41 of the centering 34. A hole 42 connects the blind hole 40 with the annular spaces 43 and 44. Reference numeral 50 denotes an upper side ring, and a tapered surface 51 extending from the side surface 12a is formed on the inner peripheral side inner surface. 52 is a lower side ring,
A tapered surface 53 extending from the side surface 12b is formed on the inner peripheral side inner surface. The centering 34 includes
The inner peripheral surfaces of the upper side ring 50 and the lower side ring 52 are fixed to be the same inner peripheral surface 54. And
The inner peripheral surface 54 is spaced from the outer peripheral surface 55 of the shank 11 by a minute gap 56.
Are opposed to each other. Reference numeral 61 denotes a joint having a through hole 62 opened on two surfaces, and an opening at one end is a blind hole 4.
The other end is connected to a working fluid supply pump (not shown) via a hose 63. A hydraulic cylinder 64 is fixed to the spindle head 1. 6
Reference numeral 5 denotes a link, and both ends thereof are rotatably connected to the machining liquid supply ring 30 and the rod 66 of the hydraulic cylinder 64, respectively. A hydraulic cylinder 67 is fixed to the spindle head 1. Reference numeral 68 denotes a clamper, which is a hydraulic cylinder 67.
The rod 70 is fixed to the lower end of the rod 69 so as to sandwich a projection 70 provided on the outer periphery of the centering 34, the upper side ring 50, and the lower side ring 52.

Hereinafter, the operation will be described. <1> When processing is performed, it is arranged in a state shown by a solid line in FIGS. First, when a working fluid supply pump (not shown) is operated,
Processing fluid is hose 63, joint 61, blind hole 40,
It is guided to the annular spaces 43 and 44 through the holes 42 and is filled around the entire circumference of the annular spaces 43 and 44. From this, the working fluid flows into the annular space 39 as an annular / film-like flow due to the minute gaps 37 and 38, and fills the entire circumference of the annular space 39.
At this time, since the working fluid filled in the annular space 39 is prevented from flowing backward by the annular and film-like flows from the minute gaps 37 and 38, most of the working fluid is from the horizontal hole 13 to the vertical hole 14 and the through hole 1.
It is supplied to the processing point via 6, 21.

Next, the operation in the case of performing the tool change after finishing the machining will be described. ◆ First, the operation of a processing fluid supply pump (not shown) is stopped to cut off the supply of the processing fluid. Next, the hydraulic cylinder 67 is operated in the direction of arrow A in FIG. 1 to move the clamper 68 to the position indicated by the two-dot chain line. Subsequently, when the hydraulic cylinder 64 is operated in the direction of arrow B in FIG. 2 to move the working fluid supply ring 30 as shown by a two-dot chain line, the periphery of the tool holder 10 is opened. In this state, the tool is changed by a normal method. When the tool change is completed, the hydraulic cylinder 64 is operated in the direction of arrow C to return the working fluid supply ring 30 to the state shown by the solid line. Subsequently, when the hydraulic cylinder 67 is operated in the direction of arrow d to return the clamper 68 to the position shown by the solid line, the projection 70 is clamped and the working fluid supply ring 30 is fixed in a closed state. Thereafter, processing can be continued by returning to the initial operation.

FIG. 4 shows a second embodiment, in which the present invention is applied to a tool having a large diameter and sufficient rigidity. That is, in the first embodiment, the machining fluid is supplied to the drill 20 via the tool holder 10, whereas the machining fluid is supplied directly to the tool from the machining fluid supply ring 30. Note that the same parts as those in FIG. 3 are denoted by the same reference numerals, and description thereof is omitted. ◆ 80
Is a boring bar inserted into the tapered hole 3 of the spindle 2 and fixed by a drawing bolt (not shown). Reference numeral 81 denotes a throw-away tip, which is fixed to the shaft end of the boring bar 80. Bowling bar 8
A groove 12 is formed in the vicinity of the upper end tapered portion 0, and this is used as an annular space 39 for supplying a machining fluid. A horizontal hole 82 is provided in a substantially radial direction from the annular groove 12, and a vertical hole 83 communicating with the horizontal hole 82 is provided. The open end of the vertical hole 83 is closed by a plug 84. Also, an oblique hole 85 communicating with the vertical hole 83 and opening toward the throw-away tip 81 is provided. ◆ The machining fluid is the annular groove 12 and the centering 3 of the boring bar 80 as a tool.
It is guided to the annular space 39 formed by 4 and supplied to the processing point through the horizontal hole 82, the vertical hole 83, and the oblique hole 85. In addition,
Other operations are the same as those in the first embodiment, and the description is omitted.

FIG. 5 shows a third embodiment. That is, in the above two embodiments, the outer peripheral surface 5 of the shank 11
5 or the outer peripheral surface 87 of the boring bar 80 is a cylindrical surface, and on both sides of the annular groove 12 are provided threaded grooves 91 and 92 having opposite twisting directions. That is, when the spindle 2 rotates clockwise, the groove 91 is formed in a right-hand thread, and the groove 92 is formed in a left-hand thread shape.
As a result, the working fluid that has moved to the minute gap 56 is
2 is led to the annular space 39 by the pumping action of 2,
Since it is fed into the vertical hole, the leakage amount of the working fluid can be reduced.

In the above three embodiments, the annular space 39 for supplying the machining fluid is formed by using the annular groove 12 for tool exchange. May be formed in the shank 11 or the boring bar 80, and the annular space 39 may be provided using this. Although the case where the cross-sectional shape of the annular groove 12 is trapezoidal is shown, the side surface 12a and the side surface 12b may be vertically asymmetric with respect to the center of the groove, that is, the vertical inclination angle may be changed. The sectional shape of 12 may be a shape other than a trapezoid such as a rectangle, a triangle, and a semicircle. Also, the case where the vertical hole 14 is provided at the axis of the shank 11 has been described. However, the position of the vertical hole 14 is not limited to the axis, and any other position can be used as long as the processing liquid can be effectively supplied to the processing point. May be provided. Furthermore, the inner periphery of the centering 34 is structured to enter the annular groove 12, but the inner diameter of the centering 34 is
Alternatively, the inner diameter of the lower side ring 52 may be equal to or larger than the inner diameter of the lower side ring 52 so as not to enter the annular groove 12. By doing so, the amount of machining fluid flowing out through the minute gap 56 increases, but even if there is an axial positional error between the tool holder 10 and the machining fluid supply ring 30, they do not interfere with each other, so that manufacturing is easy. Has the effect of becoming In the above-described embodiment, the machining liquid supply ring 30 is divided into two parts so as to be separated from and approaching the tool holder 10. However, the machining liquid supply ring 30 is moved in the axial direction as an integral structure. A configuration in which the tool holder 10 is separated and approached may be adopted. In addition, shank 11
Outer peripheral surface 55 or boring bar 80 outer peripheral surface 87
Although a means having a pumping action is provided on the both sides, means having a pumping action may be provided on both sides of the annular groove on the inner periphery of the working fluid supply ring 30.

[0013]

As described above, according to the present invention, since the machining fluid is supplied to the inside of the tool holder or the tool in a completely non-contact state, it can be used even at a high speed. Further, since consumable parts such as bearings and seals are not used, there is an effect that maintenance management is easy. In addition, since the machining fluid supply ring is configured to be able to be separated and approached from the tool holder or the tool, even in a machine tool having an automatic tool changing device, the tool can be automatically changed in the same manner as in the past, Further, since a complicated operation such as a hose connection change is not required, there is an effect that workability is improved. Further, since there is no need to change the spindle structure at all, and since the machining fluid is supplied outside the spindle head, there is an effect that problems such as damage to the bearing due to machining fluid leakage can be prevented.

[Brief description of the drawings]

FIG. 1 is a side view showing a configuration when the present invention is applied to drilling in a machining center.

FIG. 2 is a plan view of FIG. 1;

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is a sectional view showing a second embodiment.

FIG. 5 is a sectional view showing a third embodiment.

[Explanation of symbols]

 Reference Signs List 10 tool holder 12 annular groove 13 horizontal hole 14 vertical hole 30 working fluid supply ring 34 centering 37, 38, 56 minute gap 39 annular space 43, 44 annular space 50 upper side ring 52 lower side ring 64 hydraulic cylinder 67 hydraulic cylinder 68 clamper 80 boring Bar 91,92 Threaded groove

Claims (4)

(57) [Claims] 1. A tool holder or a tool having a substantially axial vertical hole communicating with a lateral hole provided in a substantially radial direction from an annular groove provided on an outer periphery and opening at one end side, and surrounding the annular groove at a small interval. And a machining fluid supply ring having a pair of machining fluid supply passages for allowing the machining fluid to flow out in an annular or film shape toward substantially both side surfaces of the annular groove. . 2. The machining fluid supply device according to claim 1, wherein the annular groove is a groove for gripping a tool of the automatic tool changer. 3. The machining fluid supply device according to claim 1, further comprising means for separating and approaching the machining fluid supply ring with respect to the tool holder or the tool. 4. A means having a pumping action is provided on both sides of the annular groove on the outer periphery of the tool holder or the tool or on both sides of the annular groove on the inner periphery of the machining fluid supply ring, and the machining fluid is fed into the vertical hole. The working fluid supply device according to any one of claims 1 to 3.