JPH0516065A - Polishing device - Google Patents

Abstract

PURPOSE:To enhance polishing accuracy in a polishing device, which is used for polishing a curved surface or the like, by providing an air vent hole on a polishing bed, forming an air chamber having a shape corresponding to a polishing surface, and adjusting the negative pressure by means of a pressure source in order to set the contact pressure between the polishing bed and a body to be polished. CONSTITUTION:A polishing bed 42 is provided with an air vent hole 6 at the same location as an air vent hole 41 for a polishing plate 4. By aligning the air vent hole 6 and with the air vent hole 41, the polishing plate 4 is fixed to the polishing bed 42. An air chamber 7, whose shape corresponds to the polishing surface of the body 1 to be polished, is formed while being communicated with the air vent hole 6. The polishing bed 42 is attached to a polishing tool 20 via a hollow, sliding shaft 44. Then, the air chamber 7 is communicated with a pressure source 46 via both a tube 27 and an air passage 28, so that the pressure of the air chamber 7 may become negative. Thus, the polishing bed 42 is attracted and press-fitted to the surface of the body 1 to be polished. Polishing work is carried out in this condition.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polishing apparatus, and more specifically, when the polishing surface of an object to be polished is a curved surface or the like, the contact pressure of the polishing table is adjusted to a constant value by pressure and The present invention relates to a polishing device which is always brought into contact along a normal direction.

[0002]

2. Description of the Related Art The applicant applied for an invention of "polishing tool" as Japanese Patent Application No. 2-158671 on June 19, 1990. FIG. 9 shows the configuration of Japanese Patent Application No. 2-158671 of the prior invention.

In FIG. 9, 1 is an object to be polished, 2 is a polishing sheet, 3 is a polishing seat, and 4 is a polishing plate composed of a polishing seat 3 to which the polishing sheet 2 is adhered. 5 is an adsorption table, 6 is a vent,
7 is an air chamber. Reference numeral 8 is a hollow shaft to which the suction table 5 is fixed, 9 is a thrust bearing provided in the hollow chamber 10, 11 is a support shaft movable in the axial direction, 12 is a tool head, and 13 is a radial bearing. The tool head 12 has a built-in rotation / vibration conversion mechanism that converts the rotation of the motor into reciprocating motion. 14 and 15 are snap rings, 16 is a collar plate, and 17 is a spring. The spring 17 is interposed between the hollow shaft 8 and the collar plate 16,
A spring pressure directed downward is applied to the hollow shaft 8 integrally with the suction table 5. 18 is a tool main body, 19 is a tool holder, 21 is a flange, 22 is a bolt, and 23 is a base. 24 is a switching valve,
25 is a vacuum pump, 26 and 27 are tubes, and 28 and 29
Is an airway. An element such as the tool body 18 constitutes a polishing tool 20. Then, the polishing tool 20 is attached to the air chuck of the polishing apparatus equipped with the robot via the die 23 (see FIG. 4).

The operation of the polishing apparatus having such a structure will be described below. When the polishing plate 4 sucked on the suction table 5 by the negative pressure of the air chamber 7 comes into contact with the surface of the workpiece 1, the air motor in the tool body 18 is driven and the tool body 18 is moved to the tool holder 1.
Vibrate along 9. With the vibration of the tool body 18, the hollow shaft 8 vibrates left and right integrally with the support shaft 11. Since the hollow shaft 8 is loosely fitted to the support shaft 11 and the downward spring pressure is applied by the spring 17, the polishing sheet 2 of the polishing plate 4 is pressed against the surface of the object to be polished 1 while vibrating left and right. There is. As a result, the polishing plate 4 vibrates while contacting the polishing sheet 2 along the surface of the object to be polished 1, and the surface of the object to be polished 1 is polished by the polishing sheet 2.

[0005]

As described above, in the conventional polishing apparatus, a constant elastic force is applied by the spring 17 to the hollow shaft 8 which is vertically movable on the support shaft 11 to cover the polishing sheet 2. The polishing body 1 is configured to be brought into contact with the surface of the polishing body 1 for polishing. Therefore, when the surface of the object to be polished 1 is a curved surface other than a flat surface, the spring 17 expands and contracts depending on the polishing position, and the contact pressure changes. Further, when the axis of the support shaft 11 moves away from the axis of the curved object 1, the polishing plate 4 contacts the polishing surface of the object 1 while being inclined. If the contact pressure of the polishing plate 4 changes or the polishing surface is inclined, the polishing of the object to be polished 1 becomes uneven, and the polishing accuracy decreases. Therefore, the elastic force of the spring 17 must always be kept constant. Further, when the object to be polished 1 has a curved surface, there is a problem that the robot of the polishing apparatus must be taught accurately in order to keep the elastic force constant. The present invention has been made to solve the problems of the conventional apparatus as described above, and the contact pressure of the polishing sheet is always kept constant, and the polishing table is brought into contact with the object to be polished with a uniform contact pressure. The present invention aims to provide a polishing apparatus having high polishing accuracy.

[0006]

According to the present invention, there is provided a polishing table in which abrasive grains are formed on a contact surface to form a plurality of ventilation holes, and a gas chamber is formed in a shape corresponding to the polishing surface of an object to be polished. A tool body that holds the polishing table slidably in the axial direction, a drive unit that drives the polishing table to contact the surface of the object to be polished through the tool body, and an air chamber that communicates with the air chamber of the polishing table. And a pressure source for making a negative pressure to suck air from the ventilation hole, and the negative pressure is adjusted by the pressure source to set the contact pressure between the polishing table and the object to be polished. Further, a polishing table having an air chamber formed in a shape corresponding to the polishing surface of the object to be polished by forming abrasive grains on the contact surface, a tool main body for slidably holding the polishing table in the axial direction, and a tool Driving means for bringing the polishing table into contact with the surface of the object to be polished through the main body and driving means, and air pressure communicating with the air chamber of the polishing table to supply positive pressure to the air chamber and bring the polishing table into contact with the object to be polished. And a pressure source for adjusting the pressure supplied to the air chamber by the atmospheric pressure source to set the contact pressure between the polishing table and the object to be polished. Further, a universal joint for connecting the polishing table so as to be tiltable is provided, and the polishing apparatus is configured so that the universal table makes contact with the polishing table in the normal direction of the object to be polished.

[0007]

[Function] When the polishing table is placed on the polishing surface of the object to be polished and the switching valve is switched to make the air chamber of the polishing table a negative pressure, the polishing table is sucked together with the sliding shaft while the outside air is sucked from the ventilation hole, and the polishing is performed. The sheet is pressed onto the surface of the object to be polished. Then, when the air motor built in the tool head is driven, the polishing table vibrates and the polishing sheet pressed against the object to be polished polishes its surface. The contact pressure applied to the object to be polished on the polishing table is adjusted by a control valve provided in an air circuit connecting the vacuum pump and the air chamber of the polishing table. Further, according to another embodiment of the present invention, a polishing apparatus having a polishing table provided with an airtight air chamber without a vent hole is also configured. Positive pressure is supplied from an atmospheric pressure source to the air chamber in the polishing table, which is made airtight, and the polishing table slides integrally with the sliding shaft to press-bond to the object to be polished. Also in this embodiment, the contact pressure of the polishing table with respect to the object to be polished is adjusted by the strength of the positive air pressure sent to the air chamber. Further, according to another embodiment, the universal joint is connected to a polishing table which is pressed against the object to be polished and polished. If a negative pressure or positive pressure is applied to the air chamber after applying it to the curved surface of the object to be polished using the polishing table connected with the universal joint, the polishing table will tilt from the universal joint and the normal will automatically be applied. It is pressed against the curved surface of the object to be polished along the direction.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an explanatory view of the structure of a first embodiment of the present invention, FIG. 2 is a sectional view of an essential part of FIG. 1, and FIG. 3 is a bottom view of a polishing table. In the embodiment of the present invention, the same or corresponding portions in the drawing of FIG. 9 described above are designated by the same reference numerals, but some of them have different structures, and some description will be duplicated, but a little more detailed description will be given here. In FIG. 1, 1 is an object to be polished such as a mold, 2 is a polishing sheet, and 3 is a polishing seat. As the polishing sheet 2, a circular sheet made of paper or cloth with abrasive grains uniformly attached to the surface thereof is used. The polishing seat 3 is made of a metal such as a hard synthetic resin or aluminum, and is formed in a shape that matches the polishing surface of the object to be polished 1 and the polishing sheet 2 is bonded to the surface. The polishing sheet 2 and the polishing seat 3 constitute a polishing plate 4, and a plurality of ventilation holes 41 penetrating in the thickness direction are provided. Reference numeral 42 is a polishing table corresponding to the suction table of FIG. 9, 6 is a ventilation hole provided in the polishing table 42, and 7 is an air chamber. The ventilation holes 6 of the polishing table 42 are the ventilation holes 41 of the polishing plate 4.
The polishing plate 4 is provided at the same position as the above, and the ventilation plate 41 is made to correspond to the ventilation hole 6 and the polishing plate 4 is fixed to the polishing table 42 with an adhesive 43 or the like (FIGS. 2 and 3). Reference numeral 44 is a hollow sliding shaft to which the polishing table 42 is attached, and 9 is a thrust bearing provided in the hollow chamber 10 of the sliding shaft 44. Polishing table 4 (not shown)
2 is fixed to the sliding shaft 44 by interposing a sealing material such as packing on the contact surface and removably closely contacting with a screw.

Reference numeral 11 denotes a support shaft, which is fitted together with the sliding shaft 44 along the thrust bearing 9 so as to be slidable in the axial direction. Reference numeral 12 is a tool head, and 13 is a radial bearing.
The tool head 12 holds the upper end of the support shaft 11 via a radial bearing 13. Although not shown, the tool head 12 has a built-in rotation / vibration conversion mechanism that converts the rotation of the air motor into a minute reciprocating motion. 14 and 15 are upper and lower retaining rings. The retaining rings 14 and 15 regulate the vertical sliding range of the sliding shaft 44.

Reference numeral 18 is a tool body, and 19 is a tool holder for holding the tool body 18. The tool body 18 vibrates in a minute range by a rotation / vibration conversion mechanism built in the tool head 12. 21 is a flange, 22 is a bolt, and 23 is a base. The bolt 22 is a tool holder 19
Is fixed to the flange 21. Reference numeral 24 is a switching valve, 45 is a control valve, and 46 is an atmospheric pressure source. The atmospheric pressure source 46 outputs positive and negative pressure. Further, 26 and 27 are tubes, 28 is a ventilation passage provided on the support shaft 11 or the like for communicating the polishing table 42 and the switching valve 24, 29 is formed in the flange 21 and the tool main body 18
Is a ventilation path that communicates with the base 23. Thus, the polishing tool 20 is constituted by the elements such as the tool body 18 described above. The mounting state of the polishing tool 20 is shown in FIG. 4, 30 is a polishing device, 31 is a work table, 3
Reference numeral 2 is a robot, 33 is an air chuck, and 34 is an arm. The polishing tool 20 is attached to the robot 32 via the base 23.
Attached to the air chuck 33.

The operation of the device of the present invention having such a configuration will be described below. In advance, the polishing tool 20 is placed on a tool stand (not shown), and a polishing table 42 to which a plurality of types of polishing sheets 2 having abrasive grains with different roughness are adhered
Are prepared with the polishing sheet 2 facing down on a tool shelf (not shown). Further, it is assumed that the object to be polished 1 having a flat polishing surface is set on the work table 31.

The arm 34 of the robot 32 of the polishing apparatus 30
Is driven, and the air chuck 33 attaches the polishing tool 20 on the tool stand by grasping it with a hand through the die 23. When the polishing tool 20 is attached, the arm 34 moves to the position of the tool rack and moves the sliding shaft 44 to the polishing table 4 on the tool rack.
Put on 2. At this time, with screws not shown,
The polishing table 42 is manually attached to the tip of the sliding shaft 44 in an airtight manner. Then, the air chamber 7 of the polishing table 42 communicates with the atmospheric pressure source 46 via the tube 27 and the ventilation path 28. Again, the arm 34 of the robot 32 is rotated in the opposite direction, and the polishing table 42 grasped by the hand is moved above the workpiece 1 on the work table 31 and set on the polishing surface. .

Here, the switching valve 24 is switched and the air chamber 7
When is communicated with the atmospheric pressure source 46 through the tube 27 and the ventilation path 28, the inside of the air chamber 7 becomes a negative pressure. At this time, since the polishing table 42 is slidably held on the support shaft 11 integrally with the sliding shaft 44, the polishing table 42 receives a suction force and is sucked and pressed onto the surface of the object 1 to be polished. . On the other hand, the tool body 18
Is connected to the atmospheric pressure source on the robot 32 side through the ventilation path 29 and the tube 26, and the air motor in the tool body 18 is driven. The rotation of the air motor is converted into slight left and right vibrations of the tool body 18 by a conversion mechanism (not shown). Then, the tool body 18 vibrates along the tool holder 19, and along with this, the support shaft 11 in which the sliding shaft 44 is loosely fitted by the thrust bearing 9 also vibrates left and right. As a result, the polishing table 42 vibrates while pressing the polishing sheet 2 along the surface of the polishing target 1, and the surface of the polishing target 1 is polished by the polishing sheet 2. In this case, the contact pressure of the polishing table 42 on the polishing surface of the object 1 to be polished is controlled by the control valve 4 which is provided in the middle of the tube 27 and controls the vacuum degree of the atmospheric pressure source 46.
Adjusted by 5. Then, the work table 31 on which the object to be polished 1 is set is sequentially driven along the planar X and Y axes, and the entire surface is polished by the polishing table 42 provided with the polishing sheet 2.

Object 1 to be polished by polishing sheet 2 of the same count
When the polishing of all the surfaces is completed, the air circuit is turned off by the switching valve 24 and the arm 34 is driven to move to the position of the tool rack. Then, the polishing table 42 to which the used polishing sheet 2 is adhered is removed and placed on the tool shelf. The polishing table 42 in which the arm 34 is attached with the polishing sheet 2 of the next count
The position is moved to the position of, and the same operation as described above is performed to attach the polishing table 42 with the polishing sheet 2 of the next count to the slide shaft 44, and the polishing operation is restarted. Such a robot 32
The replacement of the polishing table 42 and the polishing operation by the are performed almost automatically based on a fixed sequence.

FIG. 5 is an explanatory view of the configuration of the second embodiment of the present invention. In the second embodiment, a tube 36 for supplying negative pressure is connected to the polishing table 42 from the outside, and the ventilation passage 28 in the sliding shaft 44 is omitted. In addition, 5 in FIG.
0 is a universal joint. Universal joint 50 is rod end 5
1, pin 52, ball joint 53, screw holder 54
And a nut 55 and the like. Rod end 5
1 is provided on the sliding shaft 44, and the screw holder 54 is the polishing table 4
It is screwed to 2 and fixed with a nut 55. And
The universal joint 50 allows the polishing table 42 side to be inclined without being restricted by the connection.

In the second embodiment having such a structure,
Particularly, the polishing surface of the object to be polished 1 as shown in FIG. 6 is used for polishing the spherical surface. When polishing the spherical object 1 to be polished, the rotary tool main body 18 which rotates the polishing table 42 by the air motor in the tool main body 18 in advance to perform polishing is the tool holder 1.
Replaced by 9. Further, as shown in FIG. 7, a polishing table 42 having a concave polishing seat 3 matching the shape of the polishing surface of the object 1 to be polished is used. Similarly to the above, the polishing table 42 grasped by the hand is placed on the center O-O of the spherical object 1 to be polished on the work table 31 as shown in FIG. Then, the tube 46 is directly connected to the switching valve 24.
When the air chamber 7 of the polishing table 42 has a negative pressure, the polishing table 42 is sucked onto the surface of the object to be polished 1 by the suction of the outside air from the ventilation holes 41 and 6, and is pressure-bonded. As a result, the polishing target sheet 1 is rotated by the rotating polishing sheet 2 in association with the driving of the air motor.
The vicinity of the center O-O of is polished.

When the polishing near the center O--O of the spherical surface of the object to be polished 1 is completed, the negative pressure of the air chamber 7 is released by the switching valve 24, and then the polishing table 42 held by the hand is slightly lifted to make the spherical surface. Of the polishing table 42 is moved from the center OO of the polishing table 42 to move the polishing table 42 close to the polishing surface. When the air pressure of the air chamber 7 is made negative by the switching valve 24 again, the outside air is sucked from the ventilation holes 41 and 6 through the gap between the polishing surfaces as described above. At the same time, the universal joint 50 works and the polishing table 42 is tilted and pressed onto the spherical surface of the object 1 to be polished. The state at this time is shown in FIG. 7B, and the inclination angle θ automatically coincides with the normal line XX of the spherical surface of the object to be polished 1. Subsequently, when the air motor is driven, the polishing table 42 rotates while being uniformly pressed along the spherical surface of the object 1 to be polished, and polishing around the outside of the center OO of the spherical surface of the object 1 is performed. . In this way, the entire surface of the object to be polished 1 is gradually moved to the outside from the center of the spherical surface and the entire surface is polished.

FIG. 8 is a sectional view of the essential portions of the third embodiment of the present invention. The third embodiment differs from the first embodiment in that
As shown in the figure, the air chamber 7 of the polishing table 42 does not have a vent hole for sucking the outside air, and has a closed structure. Polishing table 4
2 is a direct or universal joint 50 as in the first and second embodiments.
Is connected to a sliding shaft 44 that is slidable in the axial direction. The air chamber 7 of the polishing table 42 is fed through the control valve 45 to the atmospheric pressure source 4
6, a positive pressure regulated by a control valve 45 is supplied from the atmospheric pressure source 46. Then, the object to be polished 1
The polishing table 42 is pressure-bonded to the surface of, and the object 1 is polished with an appropriate contact pressure. Further, in the case of the object to be polished 1 having a curved surface as shown in FIG. 6, as in the second embodiment, the universal joint 50 performs polishing in which the pressing direction is controlled so as to be along the normal line XX. It has become.

In the above-described embodiment, the polishing plate 4 is composed of the polishing sheet 2 to which abrasive grains are adhered and the polishing seat 3 conforming to the shape of the object 1 to be polished, and the polishing plate 4 is fixed to the polishing table 42. Although the case has been described as an example, it is not always necessary to adopt this configuration, and the polishing table 42 may be formed with abrasive grains on the surface in accordance with the shape of the object to be polished. Further, for example, a curved means or a flat object to be polished can be polished by turning on / off a lock means for locking the universal joint by utilizing an electromagnetic force of an electromagnet or a connecting pin. Further, the case where the polishing table 42 has a concave spherical surface and a flat surface has been described.
The present invention can also be applied to polishing a convex spherical surface, a triangular prism shape, or a semi-cylindrical shape.

[0020]

According to the present invention, a polishing table having a plurality of ventilation holes formed on the contact surface to form a plurality of ventilation holes and having an air chamber formed in a shape corresponding to the polishing surface of the object to be polished, and a polishing table are provided. Tool body that holds the polishing table so that it can slide in any direction, drive means that drives the polishing table to contact the surface of the object to be polished through the tool body, and communicates with the air chamber of the polishing table to create a negative pressure in the chamber. And a pressure source for sucking air from the ventilation hole, and a negative pressure is adjusted by the pressure source to set the contact pressure between the polishing table and the object to be polished. Further, a polishing table having an air chamber formed in a shape corresponding to the polishing surface of the object to be polished by forming abrasive grains on the contact surface, a tool main body for slidably holding the polishing table in the axial direction, and a tool Driving means for bringing the polishing table into contact with the surface of the object to be polished through the main body and driving means, and air pressure communicating with the air chamber of the polishing table to supply positive pressure to the air chamber and bring the polishing table into contact with the object to be polished. And a pressure source for adjusting the pressure supplied to the air chamber by the atmospheric pressure source to set the contact pressure between the polishing table and the object to be polished.
Furthermore, a universal joint that connects the polishing table so that it can be tilted is provided.
A universal joint was used to configure a polishing apparatus that brings the polishing table into contact with the object to be polished in the normal direction.

As a result, unlike the conventional polishing tool utilizing spring pressure, the contact pressure does not change due to expansion and contraction of the spring, and the supply pressure can be easily adjusted to set the contact pressure on the polishing surface. You can In addition, since a tiltable universal joint is provided in the torque transmission path of the polishing table, when the polishing table comes into contact with the surface of the object having a curved surface, the polishing table automatically moves along the normal direction of the polishing surface. It can also be pressed and polished with a uniform contact pressure. Therefore, according to the present invention, it is possible to provide a polishing apparatus having various advantages such that the polishing surface is uniform, the polishing accuracy is high, and the teaching of the robot of the polishing apparatus is easy.

[Brief description of drawings]

FIG. 1 is a configuration explanatory view of a first embodiment of the present invention,

FIG. 2 is a cross-sectional view of the main part of FIG.

FIG. 3 is a bottom view of the polishing table,

FIG. 4 is a perspective view of a polishing device,

FIG. 5 is a sectional explanatory view of a second embodiment of the present invention,

FIG. 6 is a perspective view of a part of the polishing apparatus for explaining the operation of the second embodiment of the present invention,

7 (A) and 7 (B) are operation explanatory views of the second embodiment of the present invention;

FIG. 8 is a sectional explanatory view of a third embodiment of the present invention,

FIG. 9 is an explanatory diagram of a configuration of a conventional device.

[Explanation of symbols]

1 Object to be polished, 6 vents, 7 air chamber, 18 Tool body, 30 polishing equipment, 41 vents, 42 polishing table, 44 sliding axis, 45 control valve, 46 barometric pressure source, 50 universal joint.

Claims (3)

[Claims] 1. A polishing table in which abrasive grains are formed on a contact surface and a plurality of ventilation holes are formed to have a shape corresponding to the polishing surface of an object to be polished and an air chamber is provided, and the polishing table is slid in an axial direction. A tool main body that is movably held, a drive unit that drives the polishing table by bringing it into contact with the surface of the object to be polished through the tool main body, and a negative pressure in the air chamber that communicates with the air chamber of the polishing table. And a pressure source for sucking air from the ventilation hole, and the negative pressure is adjusted by the pressure source to set the contact pressure between the polishing table and the object to be polished. apparatus. 2. A polishing table having an air chamber formed in a shape corresponding to the polishing surface of the object to be polished by forming abrasive grains on the contact surface, and a tool for holding the polishing table slidably in the axial direction. A main body, a drive means for driving the polishing table by bringing it into contact with the surface of the object to be polished through the tool body, and a polishing table for communicating with the air chamber of the polishing table and supplying a positive pressure to the air chamber. And a pressure source for bringing the object to be polished into contact with the object to be polished, and the pressure supplied to the air chamber by the pressure source is adjusted to set the contact pressure between the polishing table and the object to be polished. And polishing equipment. 3. A universal joint for tiltably connecting the polishing table is provided, and the universal table is configured to contact the polishing table in a normal direction of the object to be polished. The polishing device described.