JPH0822500B2 - Spiral groove processing equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a groove processing device for processing a spiral groove on a spherical surface portion of a pivot shaft or the like.

[Conventional technology and its problems]

Generally, a bearing clearance is formed between the spherical surface of the pivot shaft and the inner diameter surface of the bearing that supports the spherical surface, and the viscous fluid is drawn into the bearing clearance by the pumping action due to the rotation of the pivot shaft. In a dynamic pressure bearing designed to support a combined load of a radial load and an axial load, an extremely shallow spiral groove of about 5 to 30 μm is formed on one of the bearing surfaces.

The spiral groove may be provided on the inner diameter surface of the bearing or may be provided on the spherical surface of the pivot shaft.

Conventionally, a photo-etching method is used to form the spiral groove on the spherical surface.

However, the photo-etching method is not suitable for mass production because it has a large number of processing steps and is inefficient. Further, it is necessary to use an appropriate exposure mask according to the pattern of the spiral groove and the size of the spherical portion, and one exposure mask forms only a spiral groove of a specific pattern on the spherical portion having a limited outer diameter dimension. If this is not possible and the number of spiral groove patterns increases, a cost problem arises.

[Object of the Invention]

Therefore, an object of the present invention is to solve the above-mentioned inconveniences and to provide a spiral groove machining apparatus capable of extremely easily forming spiral grooves of arbitrary patterns on spherical parts of various sizes. .

[Structure of Invention]

In order to achieve the above object, the present invention provides a swivel that is swung by a rotation drive device, a work supported by the swivel, and having a spherical portion at its tip, the axis of which is a swivel centerline of the swivel. A supporting device which can be supported in a state of being orthogonal to each other and a center of a spherical portion being located on a turning center line of a swivel base, a rotating device which rotates a work supported by the supporting device around a work axis, and the supporting device. A circular grindstone that is movably supported toward the center of the spherical surface of the supported work and that has an adjustable tilt angle with respect to the work, the turning angle of the swivel base, the rotation angle about the axis of the work, and the work. And a control means for controlling the movement amount of the grindstone with respect to the spherical portion in association with each other.

[Action]

The work is supported by the supporting device, the grindstone rotated in one direction toward the spherical surface of the work is moved, and in the state where the grindstone grinds the spherical surface to the required depth, the work is rotated around the axis, In addition, the groove is ground on the spherical surface portion by rotating the swivel base. In this case, the workpiece rotates with the swivel base with the center of the spherical portion as the center and rotates about the axis in the swung state, so that the spiral groove is ground on the outer periphery of the spherical portion.

〔Example〕

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

As shown in FIG. 1, a rotary drive device 2 such as a servo actuator is supported on the upper surface of the surface plate 1, and a workpiece W is mounted on the upper surface of a swivel base 4 attached to a rotary shaft 3 of the rotary drive device 2. Support device 10 for supporting the rear end, and the support device 10
A rotating device 20 for supporting the work W supported by the.

In the supporting device 10, a bearing 11 is attached to the upper surface of the swivel base 4, a flange 13 is provided at the tip of a rotary shaft 12 supported by the bearing 11, and the flange 13 is provided at the rear end of the work W. The flange F is screwed. Due to the support of the work W, the axis of the work W is orthogonal to the center line of rotation of the swivel 4, and the center of the spherical portion B provided at the tip of the work W is arranged on the center line of swivel 4. .

Further, in the rotating device 20, the servo actuator 21 is connected to the rear end portion of the rotating shaft 12, and the rotating shaft 12 is directly rotated by the servo actuator 21.

A pair of linear rails 30 are laid on one side of the rotary drive device 2 on the upper surface of the surface plate 1, and a moving table 31 movably supported along the linear rails 30 is a moving device 40 (not shown). Moved by.

Here, although details of the moving device 40 are omitted in the figure, a screw rod is provided parallel to the linear rail 30, a nut screw-engaged with the screw rod is attached to the moving base, and the screw rod is rotated by the servo actuator 41. I am trying to move the moving table.

An air spindle 32 is arranged on the front surface of the moving table 31. The air spindle 32 is movably supported along an arc-shaped guide groove 33 having the center of the work spherical surface B as a center, and a circular rotary grindstone 35 is attached to the tip of the rotary shaft 34 of the air spindle 32. . The grindstone 35 is made of a metal-bonded product such as diamond or borazon, and has a thickness corresponding to the width dimension of the spiral groove to be ground.

Further, the grindstone 35 is located at the back of the spherical surface portion B of the work W supported by the supporting device 10, and moves toward the center of the spherical surface portion B by the back and forth movement of the moving table 31. This grindstone 35 is a guide shaft
The tilt angle with respect to the work W is adjusted by moving the air spindle 32 along 33.

The processing apparatus shown in the embodiment has the above-described structure, and when grinding the spiral groove on the spherical surface portion B of the workpiece, the rear end portion of the workpiece W is supported by the supporting device 10 and the center of the spherical portion B of the workpiece W is rotated. It is arranged on the turning center of the table 4. In that state, the movable table 31 is moved, and the movable table 31 is stopped by moving the movable table 31 to a position where a part of the outer periphery of the grindstone 35 rotated in one direction grinds a part of the outer periphery of the spherical surface portion B. Is rotated, and the work W is rotated about the axis. In this case, the grindstone 35 is tilted by a predetermined angle with respect to the axis line X of the work W according to the rotation angle of the work W and the turning angle of the turning base 4.

Now, as shown in FIG. 3, in the state where the grindstone 35 grinds a part of the back surface of the spherical surface portion B, the workpiece W in the solid line position is rotated to the position indicated by the alternate long and short dash line by the rotation of the swivel base 4.
When the work W is rotated by a predetermined angle within the rotation range, a spiral groove facing the spherical surface portion B can be formed on the outer circumference of the spherical surface portion B.

The inclination angle of the spiral groove S is determined by the rotation angle of the swivel base 4 and the rotation angle of the work W, and the respective angles are appropriately determined. The grinding start position is set in the circumferential direction of the spherical portion every time the spiral groove is ground. The spiral groove S having a pattern as shown in FIG. 4 can be ground by shifting.

As described above, the present invention provides the swivel motion of the swivel base 4 (
Axis) and rotational movement around the axis of the workpiece W (θ axis)
And movement of the grindstone 35 toward the workpiece spherical surface B (Y axis)
To form the spiral groove S, the axis, the θ axis,
By controlling the amount of movement of the Y axis, spiral grooves of an arbitrary pattern can be formed.

 FIG. 5 shows an example of the control means. Spiral groove
Axis servo actuator 2, θ axis servo actuator
The chute 21 and the Y-axis servo actuator 41 are
Axis drive circuit 201, θ-axis drive circuit 211, Y-axis drive
Motor M driven by circuit 411 , M_θ, M_YComposed of
Equipped with a reversible counter 83, for example.
The three-axis controller 82 obtained by the host computer 81
Can be controlled by program control
It Motor M , M_θAnd M_YEach has a pulse jet
Nerator PG , PG_θ, PG_YIs provided.

 In the control system shown, the host computer 81 is a
Automatically operate a machining program to perform the desired machining on the W
To achieve. The 3-axis controller 82 uses this machining program
Read, axis servo actuator 2, θ
Axis servo actuator 21 and Y axis servo actuator
Controls the operation of the data 41. This control is for cutting the groove S
At this time, the work W is oriented in the θ-axis direction while only the swivel base 4 is swung.
Axis drive circuit 201 and θ axis to rotate in the direction of θ
Speed command V for each drive circuit 211 , V_θGive
Is performed by Axis drive circuit 201 and θ axis drive
Circuit 211 is a pulse generator PG , PG_θMore motor
M , M_θMotor M while feeding back the speed of ,
M_θThe speed command V , V_θFeedback to follow
While controlling, 3-axis controller 82 is reversible
Pulse generator PG via counter 83 , PG_θThan
Motor M , M_θFeedback of rotation amount (position)
However, the swivel base 4 rotates only in the axial direction, and the work W
If it rotates by θ, the motor M , M_θTo stop
(Speed command V , V_θTo 0). Do this at the same time, Y
The grindstone 35 is attached to the Z-axis drive circuit 411 of the axis servo actuator 41.
Motor M to retract to the specified position_YTo drive
Give the command of. Movement of grindstone 35 (motor M_YAmount of rotation)
Is the pulse generator PG_YBy reversible counter 8
Feedback via 3 and retracted to a predetermined position
Then motor M_YIs stopped. When the whetstone 35 retreats,
While the robot is stopped at the above specified position, the 3-axis controller 82
Next cutting point of the workpiece W (determined by the machining program
Axis) to move to the cutting position of the grindstone 35.
Moves the actuator 2 and the θ-axis servo actuator 21
Let me make it. Then move the grindstone 35 to the cutting position and
The control by the same machining program as above is repeated.

〔effect〕

As described above, in the present invention, the workpiece is supported by the supporting device, the spherical portion of the workpiece is arranged on the turning center line of the swivel base, and the rotary grindstone inclined with respect to the workpiece is moved toward the spherical portion. The spiral groove can be formed on the outer circumference of the spherical portion by rotating the workpiece around the axis and rotating the swivel while the spherical portion is ground to a predetermined depth.

Further, by appropriately setting the rotation angle of the workpiece having the spherical surface portion and the swivel angle of the swivel supporting the workpiece, and determining the inclination angle of the grindstone with respect to the workpiece, the spiral surface of the workpiece spherical surface can be formed in an arbitrary pattern. In addition to being able to form a groove, the grindstone can be moved toward the center of the spherical surface portion, so that even if the size of the spherical surface portion changes, a predetermined spiral groove can be formed in the spherical surface portion. .

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of a grinding apparatus according to the present invention, FIG. 2 is a front view showing a grinding state of a spherical portion of the same, FIG. 3 is a plan view of FIG. 2, and FIG. FIG. 5 is a front view showing an example of a spiral groove pattern, and FIG. 5 is a block diagram showing an example of control means of the same. 2 ... Rotary drive device, 4 ... Swivel base, 10 ... Support device,
20 …… Rotating device, 35 …… Grinding stone.

Claims (1)

[Claims] 1. A swivel that is swung by a rotary drive device, and a workpiece that is supported by the swivel and that has a spherical portion at its tip, the axis of which is orthogonal to the swivel centerline of the swivel and the center of the spherical portion. A support device capable of supporting the work piece positioned on the turning center line of the turning base, a rotating device for rotating the work supported by the support device about the work axis, and a center of the spherical portion of the work supported by the support device. A circular rotary grindstone that is movably supported toward the workpiece and that has an adjustable tilt angle with respect to the work, the swivel angle of the swivel base, the rotary angle about the axis of the work, and the movement amount of the grindstone with respect to the work spherical surface. A spiral groove machining device comprising a control means for controlling them in relation to each other.