JP2657721B2 - Polishing device having force control 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 polishing apparatus for polishing or grinding a workpiece. More specifically, the polishing area and
The present invention relates to a polishing apparatus in which a polishing member such as a grinder is controlled by force control in a vicinity thereof .

[0002]

2. Description of the Related Art Polishing or grinding along a complicated curved surface shape (hereinafter simply referred to as "polishing") such as polishing of a wing surface of a jet engine blade or the like requires high-precision finishing performance. As a polishing apparatus for performing such polishing, there is known an apparatus that presses a support member of a tool against a polishing tool using an elastic member such as a spring, and performs polishing while pressing a workpiece by a pressing force of the spring. (See FIG. 7). 7, reference numeral 101 denotes a servo motor, 10
2 is a polishing apparatus main body, 103 is a pressing member, 104 is a spring,
105 is a grinder support member, 106 is a grinder, 1
07 is a potentiometer, 108 is a workpiece.

However, in the conventional polishing apparatus, only the control for keeping the pressing pressure (pressing force) of the polishing tool against the workpiece is performed, and the dynamic characteristics of the system including the spring and the tool are taken into consideration. I didn't. Therefore, it was not possible to control the vibration itself when the spring vibrates during polishing. In other words, there is a problem that polishing unevenness may occur due to the vibration of the spring, and this causes a reduction in polishing quality.

[0004] In view of the problems of the related art, the present applicant presses a support member of the tool through a resilient member by a pressing member interlocked with a servomotor against a tool for polishing the workpiece first. A means for detecting an operation angle of the support member, a means for detecting a pressing pressure of the support member against the tool, and a first to third-order time differential coefficient of the operation angle. Calculating means for calculating the first- and second-order time differential coefficients of the pressing pressure, and using the outputs from the first and second calculating means to control the servomotor control signal. By providing a servo motor command value calculating means for calculating, a polishing apparatus capable of preventing polishing unevenness due to spring vibration has been proposed (Japanese Patent Application No. 2-219452) (FIG. 6).
reference). In FIG. 6, 61 is a servo motor, 62 is a polishing apparatus main body, 63 is a pressing member, 64 is a spring, 65 is a grinder support member, 66 is a grinder, 67 is a potentiometer for detecting φa, 68 is a workpiece, and 69 is a force sensor. , 7
0 indicates a potentiometer for detecting φm.

[0005]

However, it has been found that excessive polishing occurs near the polishing start position and the polishing end position even when a polishing apparatus capable of preventing the polishing unevenness due to the vibration of the spring is used. The present inventors have conducted intensive studies on such a problem, and found that the polishing apparatus is controlled with a polishing force (pressing force) lower than a predetermined polishing force (pressing force) in the vicinity of the polishing start position, and is kept constant after the lapse of the vicinity of the polishing start position. The polishing force (pressing force) is increased to a predetermined polishing force (pressing force) with the time constant of, and then the predetermined polishing force is reached near the polishing end position.
(Pressing force) is maintained, the polishing force (pressing force) is reduced to the initial polishing force after a lapse of the vicinity of the polishing end position and with a constant time constant, so that it is generated near the polishing start position and the polishing end position of the workpiece. It has been found that excessive polishing can be prevented, and the present invention has been completed.

[0006] That is, the present invention is your vicinity polishing start position
Polishing force in the preliminary polishing end position near to provide a polishing apparatus capable of switching (pressing force) of interest.

In this specification, a region from the vicinity of the polishing start position to the vicinity of the polishing end position is defined as a polishing region.

[0008]

Means for Solving the Problems] polishing apparatus of the present invention, Ken
Polishing member and gravity counteracting gravity acting on the polishing member
A first holding member having a balance weight, and the first holding member
Between the polishing member and the gravity balance weight
A pair of shaft members provided so as to protrude therefrom, and the pair of shafts
Second holding portion rotatably engaged with each tip of the member
Material and the second holding member toward the gravity balance weight.
Between the first holding member and the projecting portion
A spring member and a damper mounted between the second holding member
Rotating means for rotating a member, and rotation of the first holding member
First rotation angle detection means for detecting an angle, and the second holding member
Polishing with second rotation angle detecting means for detecting the rotation angle of the surface
Member holding means and a value detected by the first rotation angle detecting means
And the difference between the detected value and the value detected by the second rotation angle detecting means.
Controlling the rotation angle of the rotating means to reduce the pressing force of the polishing member.
Controlling the force control means and the second rotation angle detecting means.
Controlling the rotation angle of the rotation means based on the detected value
Polishing machine having polishing position control means for controlling the position of the polishing member
Polishing unit control means, the polishing area and its vicinity
The force control by the force control means, for example, the polishing start position
Polishing with a pressing force smaller than the specified pressing force
And the pressing is performed in the vicinity of the polishing start position.
Control is performed to switch from the force to the specified pressing force.
Or a predetermined pressing force until near the polishing end position.
As the polishing is performed, the
Switch from the specified pressing force to a pressing force smaller than the aforementioned pressing force.
Control is performed, and the polishing area and
And other than its vicinity, the polishing position control means
The polishing position is controlled by the polishing .

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a polishing apparatus according to the present invention will be described in detail with reference to the accompanying drawings based on embodiments, but the present invention is not limited to these embodiments.

FIG. 1 is a block diagram of a polishing apparatus of the present invention,
FIG. 2 is a schematic diagram showing an electrical configuration of an embodiment of the present invention, FIG. 3 is a block diagram showing an embodiment of a circuit configuration of a polishing section control means (apparatus) of the present invention, and FIG. 5, FIG. 5 is a graph showing a relationship between a polishing force and a position, FIG. 6 is a schematic diagram of a polishing apparatus capable of preventing uneven polishing caused by vibration of a spring according to the earlier application of the present applicant, and FIG. It is a schematic diagram of a polishing device. In FIG. 1, 1 is a polishing member holding means (apparatus), 2 is a force control means 2a and a polishing position control means.
Polishing unit control means (apparatus) including the step 2b , 3 denotes transfer means (apparatus), 4 denotes transfer position control means (apparatus). here
Then, the relationship between polishing position control and transfer position control is extended.
Then, the transfer position control means that a polishing member such as a grinder is
A control that moves the workpiece in the tangential direction.
A grinder or other abrasive member is moved in the direction normal to the workpiece.
This refers to control for moving.

As shown in FIG. 4, a polishing member holding device 1 serving as a polishing member holding means has a U-shaped frame member (second holding member) 11 having a projecting portion 11a at the center.
And a plate-shaped member (first holding member) 12 having a U-shaped frame member 12a at one end and a weight W for gravity balance at the other end. The weight W for gravity balance cancels the influence of the pressing force due to gravity, and makes the pressing force only by the spring member. The plate-shaped member 12 is substantially parallel to the projection 11a of the U-shaped frame member 11, and the end of the plate-shaped member 12 having the U-shaped frame member 12a is the projection of the U-shaped frame member 11.
11a is provided so as to protrude in the opposite direction. The tip of the U-shaped frame member 12a of the plate member 12 is the polishing member 1
3 is held. Plate member 12 and U-shaped frame member 11
A spring member 14 for applying a pressing force to the polishing member 13 and a damper 15 for attenuating vibration by the spring member 14 are interposed between the protrusions 11a . Inside the end of the U-shaped frame member 11, shaft members 12b, 12b extending from both side surfaces of the plate member 12 are rotatably held. A gear member 12c is interposed on one of the shaft members 12b . At a position where the gear member 12c is interposed, a potentiometer 16 having a gear member 16a at the shaft end which meshes with the gear member 12c is provided. This potentiometer 16 is for detecting the rotation angle of the plate-shaped member 12. On the other hand, on the outside of the end of the U-shaped frame member 11, gear members 11b, 11b are arranged coaxially with the shaft member 12b of the plate-shaped member 12. One of the gear members 11b, 11b is provided with a motor 17 having a gear member 17a at the shaft end which meshes with the gear member 11b . Further, the other of the gear member 11b, 11b, the gear member 11
A potentiometer 18 having a gear member 18a at the shaft end which meshes with the gear b is provided. The motor 17 is for changing the pressing pressure force obtained by the spring member 14 by changing the angle between the shaped frame member 11 and the plate-like member 12 co. The potentiometer 18 is for detecting the rotation angle of the U-shaped frame member 11. Given the pressing force is obtained by maintaining the rotation angle difference of the potentiometer 16, 18 to a predetermined value.

A polishing section control device 2 as a polishing section control means
The arithmetic processing unit Ri Do from 21 and the control signal output device 22 and the rotation angle changer 23, Chikarasei of the calculation processing unit 21
The force control means 2a is executed by executing the control program.
Is realized, and the polishing position control program is executed.
This realizes the polishing position control means 2b.

The arithmetic processing unit 21 includes an input interface, an arithmetic processing element (CPU 2), and a storage element (ROM
2, RAM 2) and an output interface. R
OM2 is provided for realizing the aforementioned force control means 2a.
A program, that is, a program for controlling the driving of the motor 17, data indicating the relationship between the rotation angle difference between the potentiometers 16 and 18 and the pressing force of the spring member 14, the initial pressing force, the predetermined pressing force, and the like. is input programs and data necessary for controlling the pressing force of the advance Rutotomoni, a polishing position control means 2b
A program for realizing it is also input . RAM2
The rotation angle of the potentiometer 16, the position of the transfer device 3, data required abrasive member hold device 1 such as to maintain a predetermined pressure positions of the polishing member hold device 1 is inputted. The remaining configuration of the arithmetic processing unit 21 is the same as that conventionally used for microcomputer control, and a detailed description thereof will be omitted.

The control signal output device 22 is a coaxial cable
221 and amplifier 222 and the like coaxial cable 221 is interposed, are appropriately selected according to the required specifications of the rotation angle changer 2 3 to be controlled.

The rotation angle changing device 23 includes the potentiometers 16 and 18, a motor 17 and a spring member 14.

The polishing unit control device 2 does not necessarily need to be configured using a microcomputer, and may be configured using a wired logic circuit as shown in FIG.

[0017] a transfer device 3 and transport position control means is a transfer means transferring position controller 4 are the same as those used in the polishing member hold device 1 conventionally, details of its construction Description Is omitted.

Hereinafter, an example of a polishing method using the polishing apparatus configured as described above will be described with reference to FIG.

Before the vicinity of the polishing start position ( P 1 in the figure )
When the reaching of the predetermined distance is input from the transfer position control device 4 to the polishing unit control device 2 , the polishing member 13 is moved to the polishing position.
From the polishing position control by the control means 2b to the force control means 2a
And the pressing force of the polishing member 13
The initial pressing force (F1 in the figure) is set. Polishing member 13
The wafer is further transferred by the transfer device 3 to a polishing start position (see FIG.
Medium, P1) It is determined that the transfer position control device 4 has reached the vicinity.
Ri is input to the polishing unit controller 2, the pressing force is the force control hand
The stage 2a switches from the initial pressing force (F1 in the figure) to a predetermined pressing force (F2, F2> F1 in the figure) with a predetermined time constant. This predetermined time constant is appropriately selected from the range of several tens of milliseconds to several seconds depending on the polishing object. One example is about one second in the case of rough polishing of an aluminum mold.

Further, the initial pressing force and the predetermined pressing force are also
It is appropriately selected from the range of several hundred grams to several kilograms according to the polishing object. For example, in the case of rough polishing of an aluminum mold, the weight is 2-3 kg.

In the figure, the switching from the initial pressing force to the predetermined pressing force is performed in a straight line, but the switching is not necessarily performed in a straight line, and an appropriate curve is adopted according to a polishing object. . This curve corresponds to the control program in the ROM 2 of the arithmetic processing unit 21 , specifically, the force control unit 2a.
Of the wired logic circuit (FIG. 3).

Thereafter, the predetermined pressing force is maintained while the polishing member holding device 1, specifically, the polishing member 13 is in the polishing area.

When the polishing position is input to the polishing section controller 2 from the transfer position controller 4 in the vicinity of the polishing end position ( P2 in the figure ), the pressing force is controlled by the force controller 2a to a predetermined pressing force (in the figure, Switching from F2) to the initial pressing force (F1 in the figure) with a predetermined time constant. This predetermined time constant is appropriately selected from the range of several tens of milliseconds to several seconds depending on the polishing object. One example is about one second in the case of rough polishing of an aluminum mold. In FIG. 5, the switching from the predetermined pressing force to the initial pressing force is performed in a straight line. However, as in the case of the start of polishing, the switching does not necessarily have to be performed in a straight line. Is adopted. Soshi
The polishing member reaches a predetermined distance rearward from the vicinity of the polishing end position.
The reaching unit is controlled by the transfer position control unit 4
2, the polishing member 13 is controlled by the force control means 2
a to the position control by the polishing position control means 2b
You can switch to it.

[0024]

As described above, in the polishing apparatus of the present invention, the pressing force in the transient state near the start of polishing and the end of polishing is smaller than the predetermined pressing force. And excessive polishing near the polishing end position can be prevented. Further, since the influence of the gravity of the polishing member holding device is eliminated by the gravity balance weight, the control of the pressing force can be simplified.

[Brief description of the drawings]

FIG. 1 is a block diagram of a polishing apparatus according to the present invention.

FIG. 2 is a schematic diagram showing an electrical configuration of one embodiment of the present invention.

FIG. 3 is a block diagram showing one embodiment of a circuit configuration of a polishing section control means of the present invention.

FIG. 4 is a schematic view of a polishing member holding device.

FIG. 5 is a graph showing a relationship between a pressing force and a position.

FIG. 6 is a schematic view of a polishing apparatus capable of preventing polishing unevenness due to vibration of a spring according to the present applicant's application.

FIG. 7 is a schematic view of a conventional polishing apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Polishing member holding means (polishing member holding device) 2 Polishing part control means (polishing part control device) 3 Transfer means (transfer device) 4 Transfer position control means (transfer position control device)

Claims (3)

(57) [Claims] (1)Polishing member and weight acting on the polishing member
First holding member having a gravity balance weight for canceling a force
And the polishing member and the gravity balance of the first holding member
A pair of shafts provided to protrude laterally between the weights
Material, and rotatably engaged with the respective tip portions of the pair of shaft members.
The second holding member and the gravity of the second holding member
Projection part and front part protruding toward balance weight side
A spring member mounted between the first holding member and the first holding member;
Rotating means for rotating the second holding member;
First rotation angle detecting means for detecting the rotation angle of the first holding member
And a second rotation angle detection for detecting a rotation angle of the second holding member.
Polishing member holding means comprising an ejection means, A value detected by the first rotation angle detection means and the second rotation angle
Based on the difference between the value detected by the detection means and the rotation means,
A force control hand that controls the rotation angle to control the pressing force of the polishing member
Step and a value detected by the second rotation angle detecting means.
Controlling the rotation angle of the rotating means to adjust the position of the polishing member.
Polishing unit control means having polishing position control means for controlling
Prepared, In the polishing area and its vicinity, the force control means
Power control, Except for the polishing area and its vicinity
In other words, the polishing position is not controlled by the polishing position control means.
Be done A polishing apparatus characterized in that: 2. In the force control, a vicinity of a polishing start position is provided.
Up to this point, polishing is performed with a pressing force smaller than the specified pressing force.
And in the vicinity of the polishing start position,
The contracting force is switched to a predetermined pressing force.
The polishing apparatus according to claim 1. 3. In the force control, a vicinity of a polishing end position is provided.
Until the polishing is performed with the specified pressing force,
From the predetermined pressing force to the pressing force in the vicinity of the end position.
It is characterized by switching to a smaller pressing force
The polishing apparatus according to claim 1, wherein