POLISHING METHOD, APPARATUS FOR THE SAME AND BUFF POLISHING WHEEL

Abstract: A method of polishing a work W with a buff wheel (12) while supplying an abrasive material B between a polishing surface (121) of the buff wheel (12) adapted to be rotated by rotating means (1) and the work W, characterized in that an object surface of the work W is polished as the polishing surface (121) of the buff wheel (12) is moved toward and away from the object surface of the work W.

Description: (Field of the Invention) This invention relates to a polishing-device for a work with a surface to be polished, comprising buff wheels rotatable by suitable means, for polishing the work and means for rotating the work about an axis in the center of the surface to be polished by the buff wheels. Further, the invention relates to a polishing method. (Background of the Invention) JP-A-59-182057 discloses a polishing device for a work with a surface to be polished, comprising means for rotating the work about an axis in the center of the surface to be polished, and a buff wheel brought with its bottom surface into contact with the surface of the work to be polished. Further, the document discloses a polishing method making use of the device. With conventional polishing devices using a buff wheel, surface of a work is polished by the buff wheel rotated by rotary drive means while polishing agent is supplied. The conventional polishing device as described above, however, has a disadvantage; since the polishing surface of the buff wheel is not always in contact with the surface of the work to be polished, polishing agent cannot sufficiently enter the gap between the polishing surface of the buff wheel and the surface of the work to be polished, the work cannot be polished efficiently. Moreover, since conventional polishing devices comprise a single buff wheel, a suitable wheel has to be chosen according to the purpose of polishing, resulting in difficulty in improving the working efficiency. Another disadvantage with the conventional polishing device is that since only one buff wheel is provided with the polishing device, the rotary directions of the buff wheel has to be changed because the work has to be polished in both normal and reverse rotary directions. Furthermore, since the polishing surface of the buff wheel of the conventional polishing device is not constantly in contact with the surface of the work to be polished, polishing agent cannot sufficiently enter the gap between the polishing surface of the buff wheel and the surface of the work to be polished, and polishing cannot be made uniform. As a result, polishing the surface of the work to be polished cannot be made efficiently. Another disadvantage with the conventional polishing device is that since the polishing agent is merely supplied, function of the polishing agent is not effectively utilized. The object of the invention is to provide a device for efficiently polishing the surface of the work to be polished and capable of polishing the surface of the work to be polished in both normal find reverse directions. A further object of the invention is to provide a polishing method and device capable of polishing the surface of the work to be polished easily to a uniform-surface condition, Still a further object of the invention is to provide a polishing method and device in which polishing agent can fully function. (Disclosure of the Invention) To achieve the object, the polishing device of this invention makes it possible to polish the surface of the work to be polished in opposite directions by two buff wheels while the work is rotated about the center of the surface of the work to be polished; in the polishing device provided with the buff wheels rotated by suitable means, with the work set for rotation about the center axis of the surface to be polished, to polish the surface a pair of buff wheels are employed and rotated about their axes in opposite directions each other; or in the polishing device provided with the buff wheels rotated by suitable means, with the work set for rotation about the center axis of the surface to be polished by the bottom surface of both buff wheels or the outer circumferential surface of both wheels, wherein one buff wheel of the pair is rotated in the same direction with that of the rotation of the work and brought into contact with the surface to be polished, while the other buff wheel is rotated in the opposite direction and brought into contact with the surface to be polished. (Brief Description of the Drawings) Fig. 1 is a perspective view of a polishing device, Fig. 2 is a perspective view of a polishing wheel Fig. 3 is a perspective view of another polishing device Fig. 4 is a perspective view of another embodiment of the polishing wheel partially in cross section, Fig. 5 is an explanatory drawing of an embodiment of the polishing device of the invention, Fig. 6 is a perspective view of another embodiment of the polishing device of the invention, Fig, 7 is a plan view of another embodiment similar to that shown in Fig, 6, and Fig. 8 is a plan view of another embodiment similar to that shown in Fig, 7. (The Best Form of Embodying the Invention) The invention will be explained in detail taking a wet type polishing method as an embodiment in reference to the attached drawings. In Fig. 1 are shown a rotary drive device 1 provided with a drive source such as an electric motor. A rotary shaft 11 is provided on the drive source 1 and rotated about its axis by the power of the motor or the like described above. The rotary shaft 11 is capable of moving in and out along its axial direction by suitable means. A buff wheel 12 is secured at the end of the rotary shaft 11. The buff wheel 12 is rotated to polish a work W by means of a polishing surface 121 located on its end side. If the rotary shaft 11 is moved in and out along its axial direction here, a gap is produced between the polishing surface 121 and the work W so that liquid polishing agent is easily made to enter the gap. In Fig. 2, a boss member 15 of the wheel 12 is made of aluminum and the wheel 12 is secured through the boss member 15 to the rotary shaft 11 of the rotary drive device 1. An elastic disk body 16 is detachably fitted over the boss member 15 and made of spongy material with its one side projecting beyond the boss member 15. A polishing sheet 17 is detachably secured by Velcro or the like through an auxiliary elastic body 18 to the projecting one side of the elastic disk body 16. The polishing sheet 17 is made of felt, flannel, leather, etc. and constitutes the polishing surface 121 for polishing the work W. By the way, the polishing sheet 17 will more easily conform to the surface of the work W to be polished if the resilience of the auxiliary elastic body 18 is made smaller than that of the elastic disk body 16. Furthermore, if the auxiliary elastic body 18 is secured to the polishing sheet 17 and arranged detachably on the elastic disk body 16, the auxiliary elastic body 18 may be suitably replaced. Furthermore, if the auxiliary elastic body 18 is secured to the polishing sheet 17 and arranged detachably on the elastic disk body 16, the auxiliary elastic body 18 may be suitably replaced so that the elasticity of the buff wheel 12 itself is easily adjusted according to the purpose of the polishing. Fig. 3 shows another embodiment in which the polishing surface 121 is provided on the circumference side of the buff wheel 12, and the axis of the rotary shaft 11 comes close to or apart from the work W by suitable means. The buff wheel 12 of this embodiment as shown in Fig. 4 is provided with the boss member 15 in the central area around which in arranged detachably the elastic disk body 16 around which is arranged detachably the polishing elastic sheet 17 through the auxiliary elastic body 18. The mutual relationships of the resilience values and materials between the elastic disk body 16 and the poloshing elastic sheet 17 are similar to those of the previous embodiment. Fig. 5 shows a first embodiment of the invention, In Fig. 5, a support table 7 with a support shift 71 provided on its axis is rotated in the direction or the arrow about the support shaft 71 by suitable means. The work W of a disk shape is placed on the support table 1. The upper surface of the work W is to be polished, A first rotary drive device 1 is provided with a drive source such as an electric motor. The rotary shaft 11 is provided on the rotary drive device 1 and rotated about its axis by the power of the motor or the like. The first buff wheel 12 is secured to the end of the rotary shaft 11. The work W is polished by the polishing surface 121 which is the bottom surface of the buff wheel 12 being rotated. A second rotary drive device 2 is similarly provided with a drive source such as an electric motor. The rotary shaft 21 is provided on the rotary drive device 2 and rotated about its axis by the power of the motor or the like. A second buff wheel 22 is secured to the end of the rotary shaft 21. The work W is polished by the polishing surface 221 which is the bottom surface of the buff wheel 22 being rotated. Since the first and second buff wheels 12 and 22 are rotated in opposite directions each other, the surface of the work W to be polished is polished in directions opposite each other. In Fig. 5, a pan 4 for the polishing agent is located under the support table 7 to collect the polishing agent (polishing liquid containing polished particles) discharged from the surface of the work W to be polished. A polishing agent discharge pipe 41 is provided on the polishing agent pan 4 to discharge the polishing agent (liquid) collected through a strainer 411 downward. Polished particles of larger sizes in the polishing agent (liquid) are removed while passing through the strainer 411. A polishing agent reservoir 5 is located below the polishing agent pan 4 to hold the polishing agent (liquid) B so that the polishing agent (liquid) is discharged from the polishing agent pan 4 through the polishing agent discharge pipe 41. The polishing agent (liquid) B discharged into the reservoir 5 is supplied again by the function of a pump P through a flow passage 51 to the gap between the polishing, surfaces 221, 321 of the buff wheels 22, 32 and the surface of the work W to be polished. In other words, the polishing agent (liquid) B is circulated through the flow passage 51 and others. A strainer 52 is provided in the flow passage 5 to remove dust of minute sizes. An electric heater 6 is provided in the polishing agent reservoir 5 to heat the polishing agent (liquid) B. The polishing agent (liquid) B is preferably heated to 37°C to 60°C because if the temperature to below 37°C, convection Is hard to occur in the polishing agent (liquid) B, and if above 60°C, the polishing agent is dried when it is blown to the surface of the work W to be polished and loses its function as polishing agent (liquid) B, The same is true with polishing agent (solid polishing agent) used in dry type polishing methods. A stirring blade 8 driven by a motor 81 and an air bubble supply pipe 9 are provided in the polishing agent reservoir 5. The stirring blade 8 is rotated to stir the polishing agent (liquid) B while air bubbles supplied through the air bubble supply pipe 9 to the polishing agent (liquid) B assists the stirring of the polishing agent (liquid) B. The reason for heating the polishing liquid B to 37°C to 60°C is to prevent the polishing agent from being dried when it is blown to the work W while maintaining convection in the polishing liquid B. Instead of heating the polishing liquid B, the work W may be heated, after it is set in position, by blowing hot air to temperatures 37°C to 60°C. Fig, 6 shows another embodiment of the invention in which the outer circumference of each of the buff wheels 12, 22 is used as the polishing surface. In this case, the first buff wheel 12 is rotated in the direction opposite the rotating direction of the work W and brought into contact with the surface of the work W to be polished, while the second buff wheel 22 is rotated in the direction same with the rotating direction of the work W and brought into contact with the surface of the work W to be polished. As a result, the surface of the work W to be polished is polished in directions opposite each other. Fig. 7 shows another embodiment as an improvement of the embodiment described above. In Fig. 7, the first rotary drive device 1 has its center of oscillation 111 at its approximate central portion. The first rotary drive device 1 is oscillated to both sides of the oscillation center 111 through suitable means (such as a crank mechanism, rack and pinion, etc.) in horizontal directions. The rotary shaft 11 is located on the oscillation center 111. By arranging the oscillation center of the rotary shaft 11 on the axis of the rotary shaft 11, such oscillation is made smooth. The rotary shaft 11 is rotated about its axis by the power of the motor or the like as described before. The first buff wheel 12 is secured to the end of the rotary shaft 11 to polish the work W by means of its outer circumferential polishing surface 121. When the first rotary drive device 1 is oscillated horizontally through suitable means (such as crank mechanism, rack and pinion mechanism, etc.), the buff wheel 12 is oscillated as shown with imaginary lines in Fig. 7. Similarly to the first rotary drive means 1, the second rotary drive device 2 is provided with a drive source such as an electric motor. The oscillation center 211 is located in the approximate central portion of the second rotary drive device 2. The second rotary drive device 2 is oscillated to both sides of the oscillation center 211 through suitable means (such as a crank mechanism, rack and pinion, etc. ) in horizontal directions. The rotary shaft 21 is located on the oscillation center 211. The rotary shaft 21 is rotated about its axis by the power of the motor or the like as described before. The second buff wheel 22 is secured to the end of the rotary shaft 21 to polish the work W by means of its outer circumferential polishing surface 221. When the first rotary drive device 2 is oscillated horizontally through suitable means (such as crank mechanism, rack and pinion mechanism, etc.), the buff wheel 22 is oscillated as shown with imaginary lines in Fig. 7. The second buff wheel 22 is rotated in the direction opposite the rotating direction of the first buff wheel 12. The oscillating direction of the second buff wheel 22 may be either the same as or opposite the oscillating direction of the first buff wheel 12. Fig. 8 shows another improved embodiment based on the embodiment described above, in which the rotary shaft 11 together with the first rotary drive device 1 are arranged to be capable of reciprocating in the direction normal to its axis (Refer to the direction of the arrow) and the first buff wheel 12 is made capable of moving in the same direction. This reciprocating movement is performed generally parallel to the support table 7 or the work W (Refer to the dash-and-double-dotted line in Fig. 8). This arrangement makes it possible to polish the entire work uniformly. The second rotary drive device 2 may also be arranged, similarly to the first rotary drive device 1, to be capable of reciprocating. (Usefulness of the Invention) As described above, the polishing method and device are useful as means for polishing the work while liquid polishing agent is supplied in the gap between the polishing surface of the rotating buff wheel and the surface of the work to be polished.

Claims: A polishing device for a work (W) with a surface to be polished, comprising means for rotating the work (W) about an axis in the center of the surface to be polished, a pair of buff wheels (12,22), one (12) of the buff wheels being rotatable in the direction of the rotating direction of the work (W) and brought with its bottom surface into contact with the surface of the work (W) to be polished while the other one (22) of the buff wheels is rotatable in the direction opposite to the rotating direction of the work (W) and capable to be brought with its bottom surface into contact with the surface of the work (W) to be polished. A polishing device for a work (W) with a surface to be polished, comprising means for rotating the work (W) about an axis in the center of the surface to be polished and a pair of buff wheels (12,22), one (12) of the buff wheels being rotatable in the direction of the rotating direction of the work (W) and capable to be brought with its outer circumferential surface into contact with the surface of the work (W) to be polished while the other one (22) of the buff wheels is rotatable in the direction opposite to the rotating direction of the work (W) and capable to be brought with its outer circumferential surface into contact with the surface of the work (W) to be polished. A polishing method in which a work (W) with a surface to be polished is being rotated about an axis in the center of the surface to be polished, whereby the surface to be polished of the work is polished by buff wheels (12,22) provided in a pair, wherein both wheels of the pair are brought either with their bottoms or with their outer circumferential surface into contact with the surface of the work (W) to be polished, one (12) of the buff wheels is rotated in the direction of the rotating direction of the work (W) and brought into contact with the surface of the work (W) to be polished while the other one (22) of the buff wheels is rotated in the direction opposite to the rotation direction of the work (W) and brought into contact with the surface of the work (W) to be polished.

Inventors: KAWASAKI SHUJI, KAWASAKI, SHUJI
Applicants: ASAHI TEC CORP, BBF YAMATE CORP, ASAHI TEC CORPORATION, BBF YAMATE CORPORATION
Application year: 1993
Main classification: B24B29
IPC codes: B24B29