JP2571369Y2 - Spindle 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 spindle device used for a machine tool or the like, and more particularly, to a spindle device having a cylindrical spindle having a through hole or the like therein.

[0002]

2. Description of the Related Art For example, a machine tool such as a machining center is equipped with a spindle device as shown in FIG. This spindle device is rotatably supported via a housing 1b, two sets of angular rolling bearings 2b, 3b inside the housing 1b, and a cylindrical spindle 4b which is driven to rotate by a motor (not shown); and an inside of the spindle 4b. A draw bar 5b having an engaging portion 8b at its tip for detachably engaging a pull stat 91b of a tool 9b, and a draw bar 5b interposed between the draw bar 5b and the main shaft 4b. Belleville spring 50 that constantly biases drawbar 5b toward the rear end
b and the draw bar 5b disposed at the rear end side of the draw bar 5b.
and an unclamping cylinder 7b for releasing the grip of the pull stat 91b by the collet 53b by pressing b to the distal end side. The tool 9b has a tapered surface 4 formed on the inner periphery of the tip end of the main shaft 4b by the urging force of the disc spring 50b.
It is mounted in a state pressed against 6b.

[0003]

However, in the above-mentioned conventional spindle device, there is a problem that as the spindle 4b rotates at a higher speed, a larger noise is generated from inside the spindle. This noise is generated by the balls 23 of the angular rolling bearings 2b, 3b.
b, 33b are inner rings 21b, 31b and outer rings 22b, 32
b, the surfaces of the inner races 21b, 31b and the outer races 22b, 32b are elastically deformed when the rolling balls 23b, 33b pass through, and the elastic waves ( The main shaft 4b
When transmitted to the inside of the main shaft, it is considered that a roaring sound is generated from the space formed inside the main shaft.

The present invention has been devised in view of the above problems, and a problem to be solved is to provide a spindle device capable of reducing noise generated inside a spindle.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a housing , a cylindrical main shaft rotatably supported via a rolling bearing inside the housing, and an inside of the main shaft. A spindle device provided with a functional member provided , at least a front portion between the spindle and the functional member.
A configuration is employed in which a space formed at a position corresponding to the rolling bearing is filled with liquid.

[0006]

In the spindle device according to the present invention, at least the rolling is performed between the spindle and the functional member disposed inside the spindle.
The space formed at the position corresponding to the bearing has no space because it is filled with liquid. Therefore, when the main shaft rotates at a high speed, the elastic wave (micro vibration) transmitted from the rolling bearing toward the inside of the main shaft is not transmitted as sound, and the liquid filled in the space is not filled. When passing through, the vibration energy is attenuated. Thereby, noise generated as roaring noise inside the main shaft is reduced.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. Embodiment 1 FIG. 1 shows a cross-sectional view along the axial direction of a spindle device according to the present embodiment. The spindle device of the present embodiment is a housing 1 of a machine tool.
Sets of rolling bearings 2 and 3 disposed on both sides in the axial direction, a cylindrical main shaft 4 rotatably supported inside the rolling bearings 2 and 3, and disposed inside the main shaft 4 And a draw bar 5 having a spiral groove 57 and a spline groove 58 on its outer periphery, and a spiral groove 57 attached to the rear end of the draw bar 5.
The main components are a rotary distributor 6 that sends the coolant C to the spline grooves 58 and an unclamping cylinder 7 provided on the rear end side of the rotary distributor 6.

The rolling bearings 2 and 3 include inner rings 21 and 31 fitted on the outer periphery of the main shaft 4, outer rings 22 and 32 fitted on the inner periphery of the housing 1, and inner rings 21 and 31 and the outer rings 22.
The ball is an angular type consisting of balls 23 and 33 that are axially regulated and rolled between the balls 32. Between the inner rings 21, 31 and the outer rings 22, 32, inner ring spacers 25, 35 fitted on the outer periphery of the main shaft 4 and outer ring spacers 26, 36 fitted on the inner periphery of the housing 1 are interposed. Have been. And, the inner ring spacer 25 of each inner ring 21, 31,
The side surface opposite to 35 has a step portion 41 formed on the outer periphery of the main shaft 4 and inner rings 27 and 37 fitted on the outer periphery of the main shaft 4.
Is positioned by In addition, each outer ring 22, 32
The side opposite to the outer ring spacers 26, 36 is the housing 1
Are positioned by the stepped portion 12 formed on the inner circumference of the housing 1 and the outer rings 28 and 38 fitted on the inner circumference of the housing 1.

The main shaft 4 has a cylindrical shape having a through hole penetrating along the shaft center, and is rotatably supported inside the rolling bearings 2 and 3. A step portion 42 is formed substantially at the center of the inner circumference of the main shaft 4. A large-diameter inner peripheral surface 43 is formed on the front end side where the tool 9 is mounted, and a small-diameter inner portion is formed on the rear end side. It is a peripheral surface 44. A plurality of spline grooves 45 extending in the axial direction from the step portion 42 to a position corresponding to the rolling bearing 2 are formed in the large-diameter inner peripheral surface 43. A tapered surface 46 that supports the tool 9 to be mounted is provided on the inner periphery of the opening on the distal end side of the main shaft 4.
The main shaft 4 is driven to rotate by a motor (not shown).

The draw bar 5 has a large-diameter inner peripheral surface 43 of the main shaft 4.
A small-diameter outer peripheral surface 51 formed at a position corresponding to
And a large-diameter outer peripheral surface 52 formed at a position corresponding to the small-diameter inner peripheral surface 44 of the main shaft 4. At the distal end of the draw bar 5 on the small-diameter outer peripheral surface 51 side, an engaging portion 8 for holding the pullstat 91 of the tool 9 with the collet 83 is provided. This engaging portion 8
Is a cylindrical base 81 screwed and fixed to the inner periphery of the main shaft 4.
A pressing portion 82 fixed to the distal end portion of the draw bar 5 fitted inside the cylindrical base portion 81 with a screw, and disposed so as to be movable in the axial direction together with the draw bar 5; and the pressing portion 82 and the cylindrical base portion 81. It is composed of a collet 83 which is locked and moves in the axial direction of the pressing portion 82 and a claw-shaped tip side is opened and closed by a cam provided on the inner periphery of the cylindrical base portion 81. A guide groove 56 extending in the axial direction is formed on the large-diameter outer peripheral surface 52 of the draw bar 5, and a guide screw 55 attached to the main shaft 4 is fitted into the guide groove 56. Thereby, the draw bar 5 can move a predetermined distance in the axial direction within the through hole of the main shaft 4. Outside the small diameter outer peripheral surface 51 of the draw bar 5, one end side is the cylindrical base 81.
And a plurality of disc springs 5 such that the other end thereof abuts a step 53 between the small-diameter outer peripheral surface 51 and the large-diameter outer peripheral surface 52.
0 is provided. The drawbar 5 is constantly urged toward the rear end by the disc spring 50, whereby the collet 83 of the engaging portion 8 is closed and the pullstat 9 is pulled.
1 is maintained. Further, a spiral groove 57 is formed on the large-diameter outer peripheral surface 52 in a mesh shape in communication with the spline groove 45 formed on the inner periphery of the main shaft 4. A space formed between the main shaft 4 and the draw bar 5 mainly using the spiral groove 57 and the spline groove 45 is provided with a draw bar 5.
Is filled with a coolant liquid C sent from a rotation distributor 6 described later via a communication path 59 formed at the rear end.
This space is sealed by an O-ring 48 interposed between the draw bar 5 and the main shaft 4 on both sides in the axial direction and an O-ring 49 interposed between the draw bar 5 and the cylindrical base 81. Have been.

The rotary distributor 6 supplies the coolant liquid C sent from the pump 65 to a space between the main shaft 4 and the draw bar 5, and is mounted on the rear end of the draw bar 5. The rotary distributor 6 includes a rotary body 62 having a supply path 61 communicating with a communication path 59 of the draw bar 5, and the rotary body 62 is coaxially connected to a rear end of the draw bar 5. A pressure reducing valve 66 and a relief valve 67 are provided in the flow path of the coolant liquid C connecting the rotary distributor 6 and the pump 65, and are sent from the rotary distributor 6 to be fed by the spiral groove 57 and the spline groove 45. The pressure of the coolant C filling the inside is kept constant.

The unclamping cylinder 7 includes a drawbar 5
This is for releasing the pullstat 91 from being held by the collet 83 of the engaging portion 8 provided at the tip of the rotary distributor 6, and is disposed on the rear end side of the rotary distributor 6. When the cylinder rod 71 advances, the unclamping cylinder 7 presses the rear end face of the rotary distributor 6, whereby the tip of the collet 83 attached to the tip of the draw bar 5 is opened. 91 can be disengaged.

When the unclamping cylinder 7 is operated, the main shaft device of the present embodiment constructed as described above causes the advanced cylinder rod 71 to move against the rear end face of the rotary distributor 6 against the urging force of the disc spring 50. Is pressed, which causes the drawbar 5
The leading end of the collet 53 of the engaging portion 8 that moves together is in an open state. In this state, the old tool 9 is removed, the tip of the pull stat 91 of the new tool 9 is inserted into the collet 83, and the cylinder rod 71 is operated to retreat. The collet 83 moves to the end side, and the tip is closed accordingly.
The tool 9 is moved with the draw bar 5 until the tool 9 comes into contact with the tapered surface 46 of the main shaft 4 and is attached to the main shaft 4.

In this state, the spindle 4 is rotationally driven by the motor, and machining by the tool 9 is performed. Inner rings 21, 41
And the outer rings 22 and 32 are pre-loaded via the balls 23 and 33, so that as the main shaft 4 rotates, the balls 23 and 33 of the rolling bearings 2 and 3 move the inner rings 21 and 31 and the outer rings 22 and 33 together. 32, the inner rings 21, 3
An elastic wave (micro vibration) is generated by the elastic deformation of the surfaces of the first and outer rings 22 and 32. However, the inner rings 21, 3
The elastic wave transmitted from 1 to the inside of the main shaft 4 is filled mainly with the spiral groove 57 and the spline groove 45 formed in the draw bar 5, and the space between the main shaft 4 and the draw bar 5 is filled with the coolant liquid C. Therefore, the liquid coolant liquid C is not transmitted as sound and is filled in the space.
When passing through, the vibration energy is attenuated. Thereby, noise generated as roaring noise inside the main shaft 4 is reduced.

Since the two sets of rolling bearings 2 and 3 generate elastic waves having different frequencies, there is little possibility of resonance. As described above, according to the spindle device of the present embodiment,
Since the space formed between the main shaft 4 and the draw bar 5 is filled with the coolant liquid C mainly by the spiral groove 57 and the spline groove 45 formed in the draw bar 5, a roaring sound is generated inside the main shaft 4. And the noise generated. Embodiment 2 FIG. 2 shows a cross-sectional view along the axial direction of a spindle device according to the present embodiment.

The spindle device of this embodiment is basically the same as that of the first embodiment in that the space between the spindle 4a and the rotary shaft 5a disposed inside the spindle 4a is filled with the coolant liquid C. There is, however, a difference in that the tool 9a is configured to be attached and detached by rotating the rotating shaft 5a engaged with the tool 9a by the motor M. Therefore, the description of the points common to the first embodiment will be omitted, and the description will focus on the different points.

A rolling bearing 2a is provided inside the housing 1a.
The main shaft 4a rotatably supported via 3a has an inner peripheral surface 44a having a constant diameter except for a tapered surface 46a formed on the inner peripheral tip side. The rotating shaft 5a provided inside the main shaft 4a has an outer peripheral surface 51a having a constant diameter, and the outer peripheral surface 51a has a plurality of spline grooves or spirals extending in the axial direction from the front end surface to the vicinity of the rear end surface. A groove 58a is formed. A space formed mainly between the main shaft 4a and the rotating shaft 5a with the spline groove 58a as a main body includes:
Rotating distributor 6a and communication passage 59a from a pump (not shown)
Is filled with the coolant liquid C sent through. The rotary shaft 5a is rotatable in a through hole of the main shaft 4a by fitting a guide screw 55a attached to the main shaft 4a into an annular guide groove 56a formed on the outer peripheral surface 51a. It is arranged immovable in the axial direction. An engaging portion 8 for holding a pullstat 91a of a tool 9a by a ball 88a is provided at the tip of the rotating shaft 5a.
a is provided. The engaging portion 8a has a cylindrical base 81a fixedly screwed to the inner periphery of the main shaft 4a. Inside the cylindrical base 81a, the distal end of the draw bar 5a is rotatable relatively via a screw 82a. Connected movable base 8
3a is provided. The movable base 83a is movable in the axial direction by fitting a guide screw 85a attached to the cylindrical base 81a into a guide groove 84a formed in the outer peripheral surface so as to extend in the axial direction. It cannot rotate. A holding hole 86a into which the tip of the pullstat 91a is fitted is formed at the tip of the movable base 83a, and the cylindrical base 8 is formed on the wall surrounding the holding hole 86a.
The movable base 83 is placed on a cam 87a formed on the distal end surface of the base 1a.
A plurality of balls 88a rolling by the movement of a are provided.

At the rear end of the main shaft 4a, there is provided a motor M for rotating the main shaft 4a in both forward and reverse directions via a rotating body 62a of the rotary distributor 6a and gears 63 and 64. In the spindle device configured as described above, the tool 9
Is attached to and detached from the main shaft 4a by driving the motor M.
That is, when the motor M is driven by a predetermined amount in the forward rotation direction, the rotating shaft 5a is
5a, the engaging portion 8a
The movable base 83a is regulated by the guide groove 84a and the guide screw 85a and moves in the distal direction, and the ball 88a rolls on the cam 87a, so that the pullstat 91a of the tool 9a can be attached to and detached from the movable base 83a. Also,
In this state, when the pullstat 91a is mounted on the movable base 83a and then the motor M is driven in the reverse rotation direction, the movable base 83a moves in the rear end side direction as the rotation shaft 5a rotates in the reverse direction, and is moved from the cam 87a. When the pullstat 91a is gripped by the rolling ball 88a, the tool 9
“a” moves together with the movable base portion 83a and is fixed in a state of contact with the tapered surface 46a of the main shaft 4a.

After the tool 9a is mounted in this way,
The main shaft 4a is rotationally driven by the driving machine, and machining by the tool 9a is performed. With the rotation of the main shaft 4a, the elastic wave transmitted from the rolling bearings 2a, 3a toward the inside of the main shaft 4a is transmitted to the main shaft 4a mainly including the spline grooves 58a.
Since the space between the shaft and the rotating shaft 5a is filled with the coolant C, the coolant is not transmitted as sound, and the vibration energy is attenuated when passing through the coolant C. Therefore, also in the case of the spindle device of this embodiment,
As in the case of the first embodiment, the noise generated as a roaring sound inside the main shaft 4a can be reduced.

In the present embodiment, the spline groove 58a, which is a space filled with the coolant C, is formed by the rotating shaft 5a.
The spline groove 58a may be formed on the inner circumference of the main shaft 4a, or may be formed in a spiral shape instead of a spline shape. In the first and second embodiments, the coolant liquid C is used as the liquid to fill the space. However, the invention is not limited to this, and various liquids can be used.

Further, in the first and second embodiments, the spindle device in which the draw bar 5 and the rotary shaft 5a provided for attaching / detaching the tool are arranged inside the cylindrical spindle is described as an example.
For example, the present invention can be applied to a spindle device having a cylindrical spindle, such as a spindle device equipped with a vacuum chuck, in which a vacuum pipe for a vacuum chuck is disposed inside the spindle. .

[0022]

According to the spindle device of the present invention, since at least a space formed between the spindle and the functional member at a position corresponding to the rolling bearing is filled with the liquid, the space between the rolling bearing and the inside of the spindle is filled. acoustic wave transmitted without being transmitted a sound, and so attenuated when the vibration energy is passed through the liquid, it is possible to reduce noise generated a sound roar inside the main shaft .

[Brief description of the drawings]

FIG. 1 is a cross-sectional view along the axial direction of a spindle device according to a first embodiment.

FIG. 2 is a sectional view of a spindle device according to a second embodiment, taken along an axial direction.

FIG. 3 is a cross-sectional view along the axial direction of a conventional spindle device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Housing 2, 3 ... Rolling bearing 4 ... Main shaft 5 ... Drawbar (functional member) 6 rotation distributor 7 ... Unclamp cylinder 8 ... Engaging part 9 ... Tool 45 ... Spline groove 57 ... Spiral groove C ... Coolant liquid (liquid) )

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Futari Sugimoto 1-1-1 Asahi-cho, Kariya-shi, Aichi Prefecture Inside Toyota Koki Co., Ltd. −18431 (JP, U) JP 1-64301 (JP, U) (58) Fields investigated (Int.Cl. ⁶ , DB name) F16C 3/02 B23B 19/02 B23Q 11/00 F16C 3/035

Claims (1)

(57) [Scope of request for utility model registration] 1. A spindle device comprising: a housing ; a cylindrical main shaft rotatably supported inside the housing via a rolling bearing; and a functional member disposed inside the main shaft. At least the rolling between the main shaft and the functional member
A spindle device wherein a space formed at a position corresponding to a bearing is filled with liquid.