Surface smoothing system

Abstract: A surface smoothing system for smoothing a burr formed on a work surface of a workpiece (80) without dispersing a waste dust comprising a holder (10) provided with a plurality of curve parts (11) each projecting therefrom in a rocking manner and a rotation drive unit (20) for rotating an end face (12) from where the curve part (11) held by the holder (10) partially projects so that the curve parts (11) contact with the workpiece (80).

Description: The present invention relates to a surface smoothing system for smoothing a protrusion such as a burr, flash or a fin formed on a front surface or a back surface of a workpiece without dispersing the protrusion nor scratching the workpiece surface. Referring to Fig. 6, a workpiece 80 formed of, for example, a metal, resin, ceramics and the like, having holes 82 pierced through shearing work such as press or machining such as drill is likely to leave a tiny protrusion such as a burr 81 formed on its surface. The above sheared or machined section of the workpiece having the protrusion has been conventionally smoothed by cutting such protrusion with a file or a grind stone. Removing the protrusion through the aforementioned conventional grinding technique may generate the waste powder which scatters on a table or a floor or floats in the air as a dust. Moreover the grinding tends to cause a scratch on the workpiece surface that is required to be finished using a smooth-cut file. AU-B-513 172 discloses a rotary scraping or abrading tool comprising an assembly of at least two supporting parts in the form of bodies of revolution which are adjacent to one another and arranged coaxially so as to provide an axis of rotation for the said assembly, the tool further comprising a plurality of scraping or abrading elements in the form of circular tubular pegs which extend through, and are supported by respective sets of aligned circular holes in the supporting parts so as to be movable towards and away from the workpiece when the tool is in use, each of said pegs having at one end a head, and at the other end a working end, the working ends of the pegs projecting from one face of the said assembly while their heads bear against resilient material supported adjacent an opposite face of the assembly. An object of the present invention is to provide a surface smoothing system for smoothing a protrusion such as a burr formed on a workpiece surface without dispersing the protrusion nor scratching the workpiece surface. The object of the present invention is realized by a surface smoothing system according to claim 1. Further developments of the invention are given in the dependent claims. This and other objects, features and advantages of the present invention will become more apparent upon a reading of the following detailed description of embodiments referring to the accompanying drawings, of which : Fig. 1 is a front view of a surface smoothing system of an Embodiment 1; Fig. 2 is a bottom view of a holder of the surface smoothing system of the Embodiment 1; Fig. 3 is a sectional view along a line X-X of Fig. 2; Fig. 4 is an enlarged front sectional view of the holder of the surface smoothing system of the Embodiment 1; Fig. 5 is a plan view of a workpiece of the Embodiment 1; Fig. 6 is a sectional view of the workpiece of the Embodiment 1; Fig. 7(a), (b) and (c) represent each shape of a curve part of the surface smoothing system of the Embodiment 1; Fig. 8 is a perspective view of a holder of a surface smoothing system of an Embodiment 2; and Fig. 9 is a side elevational view of the holder of the surface smoothing system of the Embodiment 2. The surface smoothing system of the present invention comprises a holder having a plurality of curve parts projected therefrom. An end face from where each curve part projects is rotated for contacting the curve part and a workpiece surface. Being contacted with the curve part, a protrusion such as a burr formed on the workpiece surface is pressed under the curve part into a shape parallel to the workpiece surface or elongated. The burr may be pressed into a recess section. As the workpiece surface is contacted with the curve part having no edge and allowing for a rocking motion, the burr can be smoothed without scratching the workpiece surface or cutting the burr thereon. The end face from where the curve part projects is formed into a flat surface vertical to a rotation center axis (designated 12 in Fig. 1) or a curved surface vertical to the rotation center axis. The end face may be formed into a cylindrical surface to become approximately parallel to the rotation center axis (designated 31 in Fig. 8) or an elliptical revolution surface. Referring to Fig. 2, when the end face is vertical to the rotation center axis, it is preferable to arrange the curve parts 11 so that values of radius of gyration of the respective curve parts 11 are uniformly distributed without causing bias. When the end face is approximately parallel to the rotation center axis, it is preferable to arrange the curve parts 11 so as to be distributed in the direction of the rotation axis. Arranging the curve parts as aforementioned may smooth the burr formed on the workpiece surface uniformly. It is preferable to provide a mobile unit with means for holding the workpiece or the holder so as to change the contact position between the curve part and the workpiece. In addition to the rotation drive means, the mobile unit may enable the curve part to contact with the workpiece uniformly. As a result, the burr formed on the workpiece surface can be evenly smoothed. The above arrangement allows the system to smooth the burr formed on the workpiece with a wider area than that of the system by moving either the system or the workpiece. It is most desirable to pierce a secure hole through which the curve part partially projects from the end face and to provide an elastic member such as a spring elastically pressing the curve part to the secure hole. Therefore the curve part is allowed to rock as well as suitably limiting its force toward the outside of the curve part (please see Fig. 4). The curve part, thus, can be elastically contacted with the workpiece surface. When the end face is formed of a steel, it is preferable to cure the periphery of the secure hole to be harder than the other part through hardening treatment. In order to prevent the secure hole from being worn resulted from frequent contact with the curve part, the end face is formed of a steel and the periphery of the secure hole is further cured through the hardening treatment. The curve part may have a spherical body or a partially spherical body having a spherical surface by half (1/2) or a certain ratio (1/n). The curve part can be easily produced and hardly causes friction owing to its rolling characteristics. The amount of deformation of the burr can be controlled by selecting the suitable shape of the curve part. The curve part may be formed of a steel, ceramics, hard resin and the like. The workpiece formed of a metallic material such as a steel or an aluminum, ceramics and hard resin can be used. Embodiment 1 Fig. 1 shows a surface smoothing system 1 for smoothing a protrusion 81 (Fig. 6) such as a burr formed on either a front surface or a back surface of a workpiece 80. The surface smoothing system 1 is provided with a plurality of holders 10 each having a plurality of curve parts 11 projecting therefrom in a rocking manner and a rotation drive unit 20 for rotating an end face 12 from where the curve part 11 held by the holder 10 projects. The end face 12 is rotated so as to contact the curve part 11 with the workpiece 80. Referring to Fig. 1, the end face 12 has a flat surface vertical to a rotation center axis C. Referring to Fig. 2, values of the radius of gyration R of the respective curve parts 11 to the rotation center axis C are uniformly distributed without being biased to a certain value. As Fig. 1 shows, a mobile unit is provided to a conveyor 41 as means for holding the workpiece 80 in order to change the contact position between the curve part 11 and the workpiece 80. A drive unit is also provided (not shown) to drive the surface smoothing system 1 in a reciprocating manner at relatively a small amplitude. Referring to Fig. 4, a secure hole 13 for holding the curve part 11 is pierced through the end face 12 so that each curve part 11 partially projects therefrom. A spring 14 is further provided to elastically press the curve part 11 to the secure hole 13. The above curve part 11 formed of a steel has a spherical body as shown in Fig. 7(a). The workpiece 80 is a metallic plate with a large number of holes 82 pierced through the shearing work such as press punching as shown in Figs. 5 and 6. The workpiece 80 has burrs 81 formed on its surface. The surface smoothing system 1 is provided with 20 holders 10 arranged, for example, by 2 columns x 10 rows and a rotation drive unit 20 for rotating the respective holders 10. Each holder 10 is provided with 10 curve parts 11 as shown in Fig. 2. Fig. 3 is a cross sectional view of the holder 10 with the curve parts 11 removed. A code 122 of Figs. 2 and 3 represents a screw by which a front plate 121 having the end face 12 is tightened. The rotation drive unit 20 is formed of a motor 21, a shaft 211, a drive axis 22 linked to the holder, a pulley 221 and a belt 222 transmitting power from the shaft 211 to the drive axis 22. The conveyor 41 conveys the workpiece 80 interposed between the rollers 411 and 412 each rotating in an opposite direction. A code 17 of Fig. 3 represents an axis hole for embedding and fixing the drive axis 22 therein. The holder 10 having a cylindrical shape is connected to the drive axis 22. The holder 10 is formed of the front plate 121 having the end face 12 and a secure hole 13 pierced therethrough and a body section 15 having the spring 14 embedded therein. The holder 10 is driven by the rotation drive unit 20 for rotation at a high speed. The end face 12 rotates parallel to the surface of the workpiece 80. As a result, the burr 81 on the workpiece 80 in contact with the curve part 11 is pressed thereunder into a shape extended over a surface of the workpiece 80. The pressed burr 81 may be forced into the hole 82. Accordingly the surface smoothing system 1 of this Embodiment allows the protrusion such as a burr on a work surface of the workpiece 80 to be finished smoothly without dispersing the dust. The curve part 11 is not limited to the one having the spherical shape. The curve part 11 may have a hemispherical contact section 111 as shown in Fig. 7(b) or a partially spherical contact section 112 as shown in Fig. 7(c). Embodiment 2 In this embodiment, an end face 31 of a holder 30 from where the curve part 11 projects has a cylindrical surface. The rotation center axis C serves as a center axis of the cylinder body. The rotation drive axis 25 parallel to the surface of the workpiece 80 is provided to project from each end of the cylinder body. The workpiece 80 moves in the direction of A as shown in Fig. 8 vertically to the rotation drive axis 25. The holder 30 rotatably moves in a reciprocative manner in the direction of B (vertical to A). Other features are the same as those of Embodiment 1. The present invention provides a surface smoothing system for finishing the projection such as a burr on the workpiece surface without dispersing the dust resulted from cutting or scratching the surface of the workpiece. While the invention has been described with reference to embodiments, it is to be understood that modifications or variations may be made by a person of ordinary skill in the art without departing from the scope of the invention which is defined by the appended claims.

Claims: A surface smoothing system for smoothing a protrusion such as a burr (81), flash or fin formed on a front surface or a back surface of a workpiece (80), comprising a holder (10, 30) having an end face (12, 31) and a plurality of curved parts (11) each resiliently held in the holder and projecting from the end face (12, 31) and being movable in a rocking manner upon contact with the workpiece in a direction perpendicular to said end face, and a rotation drive unit (20) for rotating the end face (12, 31) from where said curve parts (11) held by said holder project, said curved parts having a spherical or partially spherical contact portion (11, 111, 112) for contacting said workpiece (80). The surface smoothing system of claim 1, wherein said end face has either a flat surface or a curve surface vertical to a rotation center axis (C). The surface smoothing system of claim 2, wherein each value of a radius of gyration of said curve part to said rotation center axis is uniformly distributed as a whole without causing bias. The surface smoothing system of claim 1, wherein an end face (31) has either a cylindrical surface or an elliptical revolution surface and a rotation center axis (C) of said holder is a center axis (25) of said cylindrical surface or a rotation axis of said elliptical revolution surface. The surface smoothing system of one of claims 1 to 4, wherein a mobile unit for changing a contact position between said curve part and said workpiece is provided with means for holding said workpiece or said holder. The surface smoothing system of one of claims 1 to 5, wherein a secure hole (13) is pierced through the end face (12,31) from where a curve part held by said holder partially projects and an elastic member (14) is provided for elastically pressing said curve part to said secure hole. The surface smoothing system of claim 6, wherein a member for forming said end face is formed of a steel material and a periphery of said secure hole is made harder than other part through hardening treatment. The surface smoothing system of one of claims 1 to 7, wherein said curve part has a spherical body. The surface smoothing system of one of claims 1 to 7, wherein said curve part has a partially spherical body.

Inventors: MORIYA KOJI, MORIYA, KOJI, Moriya, Koji, c/o Moriya Iron Works, Co., Ltd.
Applicants: MORIYA IRON WORKS CO LTD, MORIYA IRON WORKS, CO., LTD.
Application year: 1997
Main classification: B24B9
IPC codes: B24B9, B24B39