JP2895426B2 - Woodworking rotary joint for gas supply - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary tool with a shank, such as a drill and an end mill, used for woodworking and similar processing. The rotary tool has a hole inside the tool for supplying and jetting gas such as air from a cutting edge. The present invention relates to a woodworking rotary joint for supplying gas to a tool.

[0002]

2. Description of the Related Art Conventionally, as this kind of rotary joint, there is one disclosed in Japanese Utility Model Laid-Open No. 6-53103, for example. As the rotary joint disclosed in this publication, two types of a rotary joint 51 shown in FIG. 8 and a rotary joint 71 shown in FIG. 9 are disclosed, and this rotary joint 51 is constituted by a rotary shaft 52 and a housing 63. The rotating shaft 52 has a tool holding portion 56 integrally formed at a distal end side of a shaft portion 53 having a predetermined length, and a main shaft 5 of a woodworking machine at a base side.
And a screw shaft 54 attached to the screw shaft 54, and a nut 55 for preventing loosening is screwed to the screw shaft 54.
A tool mounting hole 57 is formed in the tool holding portion 56 so that a shank portion 68a of the rotary tool 68 can be inserted along the center line C of the rotating shaft 52. The female screw 58
The female screw portion 58 is screwed with a tightening bolt 59 for tightening and fixing the rotary tool 68.

A through hole 60 is formed at a depth end of the tool mounting hole 57. The through hole 60 extends from the depth end of the tool mounting hole 57 along the center line C to a vertical hole 61 having a predetermined diameter and a predetermined length, and passes through the depth end of the vertical hole 61 in the diameter direction of the shaft portion 53. The horizontal hole 62 is formed so as to communicate with it. The rotating shaft 52 thus formed
A housing 63 is provided on the outer periphery of the shaft portion 53.

[0004] The housing 63 is, for example, a tool holding portion 5.
6 is formed in a cylindrical shape having substantially the same diameter as the predetermined thickness and having a predetermined thickness at both ends thereof.
In a state where the bearing 4 is formed and fitted to the shaft 53, a bearing 65 of an end face shield type is fitted via a collar, and the rotating shaft 52 is provided rotatably with respect to the housing 63.
An air chamber 66 is provided between the rotation shaft 52 and the housing 63.
Are formed, and a bushing 67 connected to an air supply source is attached to the housing 63.

[0005] A rotary tool (woodwork cone) 68 is attached to the tool holding portion 56 of the rotary joint 51 thus formed. The rotary tool 68 includes a shank portion 68a, a flute portion 68b, and a cutting edge portion 68c. The rotary tool 68 is provided with a fine hole 69 that communicates with the through hole 60 to supply air along the axis thereof. At the same time, the fine holes 69 are bifurcated on the blade edge portion 68c side to form a jet hole 69a penetrating the blade edge portion 68c. The shank portion 68a of the rotating tool 68 thus formed is inserted into the tool mounting hole 57, and is fastened and fixed by the fastening bolt 59 with its inserted end abutting the depth end. In this state, the pore 6
9 communicates with the through hole 60.

The rotary joint 51 thus provided is attached to the main shaft 50 via its screw shaft portion 54, and the bushing 67 of the housing 63 is connected to an air supply source by a supply pipe or the like, and the main shaft 50 rotates. As a result, rotation is given to the rotary tool 68 to perform a perforation operation, and high-pressure air from an air supply source is supplied from the air chamber 66 to the through hole 6.
0, and is supplied to the small hole 69, is ejected from the ejection hole 69a to the cutting edge 68c, and is provided so as to discharge chips from the perforation.

Next, the rotary joint 71 shown in FIG.
2 and a tool gripping tool 78 are formed separately. At one end of the rotating shaft 72, a screw shaft portion 73 screwed to the main shaft 50 and, for example, a hexagonal spanner hooking portion 74 are integrally formed. On the side, a mounting hole 75 for a tool gripper 78 having a threaded portion 76 at an inner diameter portion is formed along a center line C of the rotating shaft 72, and a short end along the center line C is formed at a depth end of the mounting hole 75. A through hole 7 composed of a vertical hole 77a and a horizontal hole 77b orthogonal to the vertical hole 77a and penetrating the outer periphery of the rotary shaft 72.
7 are formed.

The tool gripper 78 is formed integrally with a grip body 79 and a screw shaft portion 82 which is screwed with a screw portion 76 of a mounting hole 75 of the rotary shaft 72. A mounting recess 80 is formed in which a tool mounting / removing mechanism 81 (description is omitted) that can be mounted or removed by one-touch operation is formed. At the depth end of the mounting recess 80, the axis of the screw shaft portion 82 (the center of the rotating shaft 72) is formed. Through hole 8 along line C)
3 are provided.

A housing 8 is provided on the outer periphery of the rotating shaft 72.
4 are formed. The housing 84 is formed in a cylindrical shape similarly to the housing 63, and a fitting recess 85 for fitting a bearing metal 86 made of, for example, an oil-impregnated metal is formed at both ends thereof. A bushing 67 connected to the source is mounted, and an air chamber 87 is formed on the outer periphery of the rotating shaft 72 by mounting the housing 84 via a bearing metal 86. The rotary joint 71 thus formed is provided with a rotary tool 68 attached to the tool gripping tool 78 by a one-touch operation, high-pressure air from an air supply source is introduced into an air chamber 87, and further through a through hole 77 and a through hole 83. It is provided so as to be supplied to the small holes 69 and to be ejected from the ejection holes 69a.

[0010]

In the rotary joints 51 and 71, however, the rotary tool 68 is supplied in a state where high-pressure air is supplied without inadvertently turning off the air supply source.
When the operator removes and replaces the rotary tool 68, if the operator does not grasp the rotary tool 68 and loosens the tightening bolt 59 or operates the sleeve of the tool attaching / detaching mechanism 81 in the loosening direction, the high-pressure air causes the rotary tool 68 to fly out at a high speed ( Experiments confirmed that it would fly a few meters while facing directly above.)
There is a problem that may cause injury to workers. The present invention has been made to solve the above-described conventional problems, and can prevent a rotating tool from jumping out when a tool is replaced, even in a state of supply of high-pressure air, thereby ensuring worker safety. It is an object of the present invention to provide a rotary joint for woodworking.

[0011]

SUMMARY OF THE INVENTION In order to solve the above-mentioned technical problem, the present invention is directed to a rotary joint having an opening at an outer periphery of a rotary shaft and the other end located at a depth of a tool mounting hole of a tool holding portion. within the opening to the through hole, when moving in the direction in which the tool that has been inserted into the tool attachment hole is out, and by providing a mechanism for cutting off the supply of gas, the invention of claim 2 is provided in the gas
A mechanism for shutting off the supply, a valve member for opening and closing the through hole,
Urging means for urging the valve member in a direction for blocking the through hole;
And the valve member is interlocked with the movement of the tool.
The opening of the through hole is configured to be opened and closed .
Invention, the biasing means is a coil spring, according to claim 4
In the invention, the urging means may be a gas supply pressure that is a gas supply pressure.
It is a rotary joint for woodworking for feeding. With this, even when the rotary joint is in a gas supply state, when the rotary tool moves in a direction away from the tool gripping portion, the supply of gas is automatically shut off, thereby preventing the tool from popping out when replacing the rotary tool. Thus, the safety of workers can be ensured.

[0012]

DETAILED DESCRIPTION OF THE INVENTION Next, embodiments of the present invention will be described with reference to the drawings, FIG. 1 is a cross-sectional view of a rotary joint 1, the rotary joint 1 is furnished to the rotation shaft 2 of the rotary shaft 2 Toko And a housing 27 externally mounted on the rotating shaft 2.

The rotary shaft 2 has a shaft 3 and a screw shaft 4 on one end of which a screw 4a screwed to a main shaft 50 of a woodworking machine is formed. A groove 3a for a retaining ring 36 is recessed in the outer periphery near the end of the screw shaft 4, and a tool grip 5 is integrally formed on the other end of the shaft 3. A tool mounting hole 6 is formed in the center of the tool grip 5 along the center line C of the rotary shaft 1 so that a shank 68a of the rotary tool 68 can be inserted. In the direction of the center line C, a female screw portion 7 penetrating through the tool mounting hole 6 is screwed at a predetermined interval to tighten and fix the shank portion 68a, and a tightening bolt 8 is screwed to the female screw portion 7. Further, a wrench hooking recess 9 is provided on the outer circumference in the diametrical direction which is phased by 90 degrees with respect to the female screw portion 7.
Is recessed.

At the depth end of the tool mounting hole 6, a mounting hole 10 of a gas shut-off mechanism 15 having a diameter slightly smaller than that of the tool mounting hole 6 is formed. Spring seat 1 of coil spring 25 that constitutes shutoff mechanism 15
1 is drilled. A screw portion 12 for mounting a slide tube 16 of a gas shutoff mechanism 15 is screwed in a predetermined range from an end of the tool mounting hole 6 of the mounting hole portion 10.
A through hole 13 is formed at a predetermined position of the mounting hole portion 10 so as to penetrate in the diameter direction of the shaft portion 3, and an outer peripheral portion passing through the through hole 13 is wider than the diameter of the through hole 13. The concave groove 14 is provided. The gas blocking mechanism 15 is housed in the mounting hole 10 thus formed.

The gas shut-off mechanism 15 comprises a slide tube 16, a slide valve 20, and a coil spring 25.
The slide tube 16 has a threaded portion 1 of the mounting hole 10 on an outer peripheral portion.
2 is formed in a cylindrical shape having a threaded portion 17 to be screwed with,
At one end thereof, a flange portion 18 is formed which fits into the tool mounting hole 6 of the tool holding portion 5. Also, the slide valve 20
Is formed with a slide shaft portion 21 of a predetermined length which is slidably fitted to the slide tube 16, and a flange portion 22 is formed at one end (upper end) of the slide shaft portion 21. A convex shaft 23 through which one end of the coil spring 25 is inserted is formed. A through hole 24 having a predetermined length is formed in the center of the slide shaft portion 21 to open in the tool mounting hole 6 along the axis thereof. A through hole 24a is provided.

The slide shaft 16 of the slide valve 20 is provided with an O-ring 26 on the slide tube 16 thus formed.
a, and one end of a coil spring 25 having a predetermined spring pressure is fitted on the convex shaft 23, and an O-ring 26b is fitted on the slide tube 16 in this state. By screwing the screw portion 17 of the slide tube 16 into the screw portion 12 of the mounting hole portion 10 at the other end, the other end of the coil spring 25 is fitted into the spring seat 11 provided in the mounting hole portion 10, and further, the slide tube O-ring 26b
Are resiliently attached to the end of the tool mounting hole 6 so that
7, the airtightness of the screwing gap of the coil spring 25 is secured.
Is elastically compressed, the slide valve 20 is urged toward the tool mounting hole 6, and the end of the slide shaft 21 is protruded by a predetermined length s toward the tool mounting hole 6, and the through hole 24 a is connected to the slide pipe 16. The O-ring 26a is elastically adhered to the end face of the slide tube 16 by the flange portion 22, so that airtightness of a gap between the slide shaft portion 21 and the inner diameter portion of the slide tube 16 is ensured. As described above, the housing 27 is attached to the outer periphery of the shaft portion 3 of the rotating shaft 2 in which the gas shutoff mechanism 15 is provided.

As shown in FIGS. 1 and 2, the housing 27 has a fitting base 28 having a predetermined width H which is fitted to the outer periphery of the shaft 3 and a projection 29 projecting from the base at a predetermined height. Then, for example, as shown in the figure, it is formed into a deformed substantially octagonal outer shape which is symmetrical in the front-rear direction.
A fitting recess 30 having a predetermined diameter for fitting a shield type bearing 31 is formed above and below the base 28 concentrically with the fitting hole 30.
2, a partition 33 having a predetermined width is formed between the fitting recesses 32. The convex portion 29 is formed with an inlet 34 for connecting a supply pipe or the like from an air supply source to introduce high-pressure air. A supply hole 35 for high-pressure air that penetrates the fitting hole 30 from the partition wall 33 is formed at the bottom of the introduction port 34.
The bearing hole 31 is fitted into the upper and lower fitting recesses 32 of the housing 27 formed as described above, and the supply hole 35 is formed in the recessed groove 14 recessed in the outer periphery of the shaft portion 3 in a state of being fitted outside the shaft portion 3.
The housing 27 is stopped by a retaining ring 36, and in this state, the rotating shaft 2 is rotatably supported by the housing 27.

The rotary joint 1 thus formed is attached to the main shaft 50 of the woodworking machine via the screw shaft portion 4, and a supply pipe from an air supply source is connected to the inlet 34 of the housing 27. In this state, the slide valve 20 of the gas shut-off mechanism 15 is urged by the coil spring 25 so that the through hole 24a is immersed in the inner diameter of the slide pipe 16 and the slide shaft 21
Is a predetermined length s toward the tool mounting hole 6 side of the tool gripper 5.
It is protruding. In this state, the rotary tool 6 is inserted into the tool mounting hole 6.
8 is pushed into the projecting slide shaft 21 against the coil spring 25, and the tool gripping portion is held in a state where the end of the shank 68a is in contact with the slide tube 16 as shown in FIG. The rotary tool 68 is tightened and fixed by screwing the tightening bolt 8 of No. 5. In this state, the small holes 69 of the rotary tool 68 communicate with the through holes 24 of the slide valve 20,
Also, the through hole 24a of the slide valve 20 is
6 and is pushed out and held at substantially the same position as the through hole 13 of the shaft portion 3. When the main shaft 50 rotates in this state, rotation is given to the rotary tool 68 to perform a perforation operation, and high-pressure air from an air supply source is introduced into the concave groove 14 from the introduction port 34 through the supply hole 35, and further, Through holes 13, 2
It is supplied to the fine holes 69 via 4a and 24, is jetted from the jet holes 69a to the cutting edge 68c, and chips are discharged from the perforations.

When the rotary tool 68 is replaced, when the tightening bolt 8 is loosened while supplying high-pressure air, the slide valve 20 is instantaneously moved by the pressure of the high-pressure air and the restoring force of the coil spring 25, and the through-hole is opened. 24a is the slide tube 16
The high pressure air is cut off by being immersed in the inside diameter of
The gap between the inner diameter of the slide tube 16 and the slide shaft 21 is O
The ring 26a is elastically adhered to prevent air leakage.

Therefore, when the rotating tool 68 is loosened, the rotating tool 68 stops moving only by the protrusion dimension S of the slide shaft portion 21 and is prevented from jumping out at a high speed as in the prior art, so that the operator is prevented from moving out. Safety can be ensured. Further, the housing 27 includes a fitting base 28 externally fitted to the shaft portion 3 of the rotating shaft 2 and a projection 2 projecting from the fitting base 28.
9 are formed, and the fitting recess 32 of the bearing 31 formed concentrically with the fitting hole 30 of the fitting base 28, that is,
Since the high pressure air inlet 34 is provided in the convex portion 29 outside the radius of the bearing 31, the bearing 31
Is significantly shorter than the conventional housings 63 and 84, and the tool holding portion 5 is formed integrally with the wrench hooking recess 9, so that the conventional nut 55 or the spanner hooking portion 74 is formed.
Since the mounting and forming parts of the rotary joint 1 are eliminated and the entire length of the rotary joint 1 is shortened as much as possible, there is a secondary effect that the shaft runout of the rotary tool 68 can be reduced and the machining accuracy can be improved.
You .

In the above embodiment, the gas shut-off mechanism 15 is exemplified by the slide tube 16 and the slide valve 20 having the through holes 24 and 24a. However, the present invention is not limited to this. The structure of the gas shutoff mechanisms 37 and 41 shown in FIG. That is, the gas shut-off mechanism 37 shown in FIG. 4 and FIG.
Which is installed in a mounting hole 10A formed at the center of the shaft portion 3 at the depth end of the tool mounting hole 6 of the tool holding portion 5 of
A through hole 13 is provided at the depth end of the mounting hole 10A in the diametrical direction of the shaft portion 3, and the gas shut-off mechanism 37 mounted on the mounting hole 10A is provided with a valve seat member 3 as shown in FIG.
8 and a ball valve 40. The valve seat member 38 is formed in a cylindrical shape fitted into the mounting hole portion 10A, and an opening hole 39b having a valve seat surface 39a formed in the inner periphery of the end of the valve seat member 38 on the tool mounting hole 6 side. Valve seat 3 with
A ball valve 40 having a predetermined diameter is fitted in the valve seat member 38. Thus, the ball valve 40
Is fitted in the mounting hole 10A. Other configurations are the same as those of the rotary joint 1.

With the rotary joint 1 containing the gas shut-off mechanism 37 mounted on the main shaft 50 of the woodworking machine, the ball valve 40 is seated on the valve seat surface 39a of the valve seat 39 as shown in FIG. A part 40a of the spherical surface of the ball valve 40 projects from the opening hole 39b toward the tool mounting hole 6 as shown by a broken line, and the opening hole 39b is closed. A groove 68d is formed in the end face of the shank portion 68a of the rotary tool 68 attached to the tool attachment hole 6 in a linear or cross shape around the small hole 69. Is prevented from being closed, and the end of the groove 68d is closed. The rotating tool 68 provided in this manner
By inserting the shank portion 68a into the tool mounting hole 6 and tightening it with the tightening bolt 8, the protruding portion 40a protruding into the tool mounting hole 6 is pushed in, and the ball valve 40 is mounted on the valve seat surface of the valve seat 39. A gap t is formed between the ball valve 40 and the valve seat surface 39a at an undefined position with respect to the valve 39a. When high-pressure air is introduced in this state, the high-pressure air is supplied to the fine holes 69 through the gap t. When the tightening bolt 8 is loosened when the rotary tool 68 is replaced, the ball valve 40 is instantaneously positioned at the fixed position of the valve seat 39 by the pressure of the high-pressure air, the opening hole 39b is closed, and the supply of the high-pressure air is shut off. Thus, the rotating tool 68 is prevented from jumping out.

Next, the gas shut-off mechanism 41 shown in FIGS. 6 and 7 comprises a valve seat member 42 and a pin valve 45, and this valve seat member 42 is mounted in the mounting hole 10A of the rotary shaft 1 described above. A large-diameter hole 43a and a small-diameter hole 43b are formed in a stepped shape at the center thereof, and a valve seat surface 44 is formed in the stepped portion at a predetermined angle. Also,
The pin valve 45 has a smaller diameter than the large-diameter hole 43a of the valve seat member 42 and has a gap t1 and a slidably fitted head 45.
a and the pin portion 4 slidably fitted in the small-diameter hole 43b.
5b is formed integrally, and a valve face 46 is formed on the pin portion 45b side of the head portion 45a so as to abut on the valve seat surface 44 of the valve seat member 42. The tip of the pin portion 45b is notched obliquely at a predetermined angle to form an inclined surface 45c, and the ventilation groove 47 is recessed at an interval of, for example, 90 degrees in the outer peripheral longitudinal direction of the pin portion 45b. Has been established. By mounting the pin valve 45 through the valve seat member 42 thus formed in the mounting hole 10A, when high-pressure air is introduced from the introduction port 34, the pressure acts on the end face of the head 45a. The valve face 46 is in contact with the valve seat surface 44 to form a ventilation groove 47 formed in the pin portion 45b.
In this state, the distal end side of the pin portion 45b projects toward the tool mounting hole 6 for a predetermined length. Therefore, when the rotary tool 68 is tightened and fixed in the tool mounting hole 6, the pin valve 45 is pushed in as shown in FIG. 6, the valve face 46 is separated from the valve seat surface 44, and the gap t1 communicates with the ventilation groove 47. Thus, the high-pressure air is supplied to the small holes 69 of the rotary tool 68. When the tightening bolt 8 is loosened when the rotary tool 68 is replaced, the pressure of the high-pressure air instantaneously acts on the head 45a of the pin valve 45, the pin valve 45 is pushed out, and the valve face 46 comes into surface contact with the valve seat surface 44. As a result, the high-pressure air is shut off, and the rotary tool 68 is moved only by the amount of protrusion of the pin valve 45 and is prevented from jumping out.

As described above, the gas shut-off mechanism has various structures as described above.
8a is inserted into the tool mounting hole 6 to release the high-pressure air, and when the fastening of the shank 68a is released,
Any configuration may be used as long as it can shut off high-pressure air instantaneously. In the above embodiment, the gas shut-off mechanism of the tool grip 5 for fixing the rotary tool 68 with the tightening bolts 8 is illustrated as an example. However, a tool grip with a mechanism for attaching and detaching the rotary tool by one-touch operation is provided. Also, these gas shut-off mechanisms can be applied. In addition, although the shield type bearing 31 is illustrated as being fitted to the bearing of the housing 27, the invention is not limited to this, and an oilless bearing such as an oil-impregnated metal may be used. Further, although the outer shape of the housing 27 is illustrated as being formed in a deformed octagonal shape, it is not limited to this, and may be formed in, for example, a substantially rectangular block shape, an elliptical shape, or a substantially egg shape. When a plurality of rotary joints are mounted on a machine having a plurality of spindles, such as a multi-axis drilling machine, the rotary joints may be individually mounted. However, the housing is housed in one case, and a supply pipe from a gas supply source is provided. May be one.

[0025]

According to the present invention, as described above, even when the rotary joint is in a gas supply state, the supply of gas is automatically shut off when the rotary tool moves in a direction away from the tool gripping portion. Therefore, it is possible to prevent the tool from jumping out at the time of changing the rotary tool, thereby ensuring the safety of the operator. In addition, the axial length of the housing can be shortened, the total length of the rotary joint is shortened accordingly, and shaft runout is eliminated, so that machining accuracy with the rotary tool can be improved, and quality can be improved. There are side effects that can be made .

[Brief description of the drawings]

FIG. 1 is a sectional view of a rotary joint for woodworking.

FIG. 2 is a bottom view on the tool gripping portion side.

FIG. 3 is an explanatory diagram of an operation of a gas shutoff mechanism.

FIG. 4 is a sectional view of another gas shutoff mechanism.

FIG. 5 is an enlarged sectional view of the gas shut-off mechanism of FIG.

FIG. 6 is a sectional view of another gas shutoff mechanism.

FIG. 7 is a sectional view taken along line AA of FIG. 6;

FIG. 8 is a sectional view of a conventional woodworking rotary joint.

FIG. 9 is a sectional view of another conventional rotary joint for woodworking.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rotary joint 2 Rotation shaft 3 Shaft part 5 Tool holding part 6 Tool mounting hole 15, 37, 41 Gas shut-off mechanism 24, 24a Through-hole

Claims (4)

(57) [Claims] 1. A tool inserted into a tool mounting hole moves in a direction in which a tool inserted into a tool mounting hole comes off into a through-hole that opens on the outer periphery of a rotary shaft of a rotary joint and has the other end open behind a tool mounting hole of a tool grip. A rotary joint for woodworking for gas supply, wherein a mechanism for shutting off gas supply is provided. 2. A mechanism for shutting off the supply of the gas,
A valve member for opening and closing the through hole, and shielding the valve member from the through hole
Biasing means for biasing the valve member in a direction
Is configured to open and close the through hole in conjunction with the movement of the tool;
The woodworking rotary joint for gas supply according to claim 1 . 3. The biasing means is a coil spring.
Item 2. A rotary joint for woodworking for gas supply according to item 2. 4. The apparatus according to claim 1, wherein said urging means is a gas supply pressure.
The rotary joint for woodworking for gas supply according to claim 2.