JP2010179427A - Centerless grinding device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a centerless grinding device, capable of suppressing chipping in grinding of a small ferrite material. <P>SOLUTION: The centerless grinding device 1 includes: an adjustment wheel 3 which rotates a grinding object 9; a grinding wheel 5 which is rotatably supported and grinds the grinding object; and a carrier 7 which is disposed between the adjustment means and the grinding wheel to support each of grinding objects so as to be rotatable, and guides and advances a plurality of grinding objects in a revolution circular route. The adjustment wheel and the grinding wheel respectively includes an adjustment circular part 3a and a grinding circular part 5a, the adjustment circular part and the grinding circular part being disposed so that the circular protruded side faces the circular recessed side. The revolution circular route is disposed to pass through between the circular protruded side and the circular recessed side. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a centerless grinding apparatus.

  In winding parts such as transformers and coils, windings are wound around a ferrite core. The ferrite core includes a core portion around which the winding is wound, and a flange portion provided on both sides thereof and having a larger diameter than the core portion. Such a shape of the ferrite core has produced a relatively small-diameter winding core portion and a large-diameter collar portion by grinding the middle portion of the rod-shaped core material while leaving almost both end portions. Moreover, the ferrite core of the winding component used as an electronic component is extremely small, and has conventionally been processed into the shape as described above using a centerless grinding apparatus (see, for example, Patent Document 1).

  The existing centerless grinding apparatus includes a grinding wheel and an adjustment wheel that are rotatably supported and arranged at an appropriate interval, and a support blade that is arranged between the grinding wheel and the adjustment wheel. The object to be ground, which is a core, is rolled while being in contact with the outer periphery of the grinding wheel, the outer periphery of the adjustment wheel, and the upper end surface of the support blade, and is ground into a predetermined shape.

  However, when an extremely small ferrite material is ground by the existing centerless grinding apparatus having the above-described configuration, there is a problem that cracks and chips are generated.

JP 2008-12616 A

  The present invention has been made in view of the above, and an object thereof is to provide a centerless grinding apparatus capable of suppressing cracking and chipping in grinding a small ferrite material.

  In order to solve the above-described problems, a centerless grinding apparatus according to the present invention is disposed between the adjusting means and the grinding means, and supports each of the objects to be rotated in a rotatable manner, and revolves a plurality of objects to be ground. Conveying means for guiding and advancing along an arcuate route, the adjusting means and the grinding means each having an adjusting arcuate part and a grinding arcuate part, the adjusting arcuate part and the grinding arcuate part comprising an arcuate convex side and an arcuate concave part, respectively. The revolving arcuate route is arranged so as to pass between the arcuate convex side and the arcuate concave side.

  The grinding means may be arranged on the revolution center side of the revolution arcuate route.

  The adjusting means is an adjusting wheel configured in an annular shape, the grinding means is smaller in diameter than the adjusting wheel, and both the grinding means and the conveying means are arranged inside the adjusting means. You may make it.

  According to the above-described present invention, crack chipping can be suppressed in the grinding of the ferrite material.

  Further, if the grinding means is disposed on the side of the revolution center of the revolution arcuate route, grinding can be performed inside the arc of the route traveling in the arcuate shape, whereby the diameter of the grinding means can be reduced. Therefore, highly accurate grinding is possible and the centerless grinding apparatus can be made compact.

  Moreover, if both the grinding means and the conveying means are arranged inside the annular shape of the adjusting wheel, the adjusting wheel, the grinding means, and the conveying means are all arranged in the space occupied by the adjusting wheel. Can be made compact.

  The other features of the present invention and the operational effects thereof will be described in more detail with reference to the accompanying drawings.

It is a figure which shows the characteristic structure in the centerless grinding apparatus which concerns on embodiment of this invention. It is sectional drawing which follows II-II of FIG. In the centerless grinding apparatus which concerns on this Embodiment, it is a figure shown including the site | part regarding supply, holding | maintenance, and discharge | emission of a to-be-ground object. FIG. 3 is a side view of a modified embodiment according to the present invention. FIG. 6 shows from the side a further modified embodiment according to the invention.

  Embodiments of a centerless grinding apparatus according to the present invention will be described below with reference to the accompanying drawings. In the drawings, the same reference numerals indicate the same or corresponding parts. In addition, the description of the direction in the specification and claims of the present application is a description in which the direction along the rotation center of the carrier or the like described later is the left-right direction, and the upper and lower directions of the paper surface in FIGS. .

  The centerless grinding apparatus 1 includes an adjusting wheel 3 that is a specific example of the adjusting means, a grinding wheel 5 that is a specific example of the grinding means, and a carrier 7 that is a specific example of the conveying means. The adjustment wheel 3 rotates the object 9 to be ground, and in the present embodiment, the adjustment wheel 3 is formed in an annular shape and is rotatably provided. Here, when the form of the workpiece 9 is illustrated, the workpiece 9 is used as a ferrite core in a winding component such as a transformer or a coil, and is provided on both sides of the winding core portion 9a around which the winding is wound. And a flange portion 9b having a larger diameter than the wound core portion. Such a shape of the work piece 9 creates a relatively small-diameter core portion and a large-diameter collar portion by grinding the middle portion of the rod-shaped core material while leaving substantially both end portions. The grinding wheel 5 has a thin disc shape on the left and right, and is rotatably supported.

  The adjustment wheel 3 and the grinding wheel 5 have an adjustment arc-shaped portion 3a and a grinding arc-shaped portion 5a, respectively. The adjustment arc-shaped portion 3a and the grinding arc-shaped portion 5a are arranged so that one arc-shaped convex side and the other arc-shaped concave side face each other. In particular, in the example of the present embodiment, as is apparent from FIG. 1, the adjustment wheel 3 and the grinding wheel are in a relationship in which the arcuate concave side of the adjustment arcuate portion 3a and the arcuate convex side of the grinding arcuate portion 5a face each other. 5 is arranged.

  The carrier 7 is disposed between the adjusting wheel 3 and the grinding wheel 5 and sequentially supplies a plurality of objects 9 to be ground between them, and discharges the object 9 from between them after grinding. is there. In the present embodiment, the carrier 7 is also configured to be annular and rotatably provided. The carrier 7 has accommodation pockets 11 (see FIG. 3) penetrating in the radial direction at equal intervals, and the workpiece 9 can be accommodated in each of the accommodation pockets 11. Further, the carrier 7 guides and advances the workpiece 9 accommodated in the accommodation pocket 11 along a revolution arcuate route. That is, each of the objects 9 to be ground is supported in the accommodation pocket 11 of the carrier 7 while being able to rotate by the action of the adjusting wheel 3, and further, a predetermined angular range ( Revolved by less than one round). The revolution arcuate route by the carrier 7 is arranged so as to pass between the arcuate convex side and the arcuate concave side.

  The grinding wheel 5 is rotatably arranged on the revolution center (rotation center CL) side in the revolution arcuate route of the workpiece 9. In the present embodiment, the grinding wheel 5 is arranged on the inner side of the adjustment wheel 3 because the adjustment wheel 3 has an annular shape. The diameter of the grinding wheel 5 is smaller than the diameter of the adjustment wheel 3. In addition, as shown in FIG. 2, the width of the grinding wheel 5 corresponds to the target width of the core 9a of the workpiece 9 and the width of the adjustment wheel 3 is substantially the same as that of the rod-shaped core material. Since it corresponds to the full length, it is smaller than the width of the adjustment wheel 3.

  In addition to these, the centerless grinding apparatus 1 according to the present embodiment is provided with a supply chute 13, a work guide 15, a work stopper 17, a drop prevention guide 19, and a discharge chute 21. As shown in FIG. 3, the supply chute 13 is a cylindrical (or bowl-shaped) long member, and contains a plurality of objects 9 to be ground in a row. The outlet 13 a of the supply chute 13 faces the accommodation pocket 11 opened on the inner peripheral side of the carrier 7, and the empty accommodation pocket 11 of the rotating carrier 7 properly faces the outlet 13 a of the supply chute 13. At this time, the workpiece 9 in the supply chute 13 is supplied to the storage pocket 11. In the present embodiment, the supply chute 13 is arranged so as to extend in the vertical direction, and the workpiece 9 is placed in the accommodation pocket 11 by dropping due to its own weight. It is not limited to the supply mode and can be appropriately modified.

  The work guide 15 is a plate-like one disposed on both the left and right sides of the carrier 7. The work guide 15 is formed in an arc shape along the annular curve of the carrier 7. The work guide 15 prevents the workpiece 9 supplied into the storage pocket 11 by the supply chute 13 from coming out of the storage pocket 11 left and right while the carrier 7 is rotating. It has the role of guiding the left and right positions of the workpiece 9 to appropriate positions for grinding. It is preferable that the left-right distance of the work guide 15 is set so as to become narrower as it approaches the work stopper 17.

  The work stopper 17 is a plate-like member disposed on one side of the portion of the carrier 7 that faces the grinding wheel 5 (see also FIG. 2), and positions the workpiece 9 in the left-right direction during grinding. Do. It can be said that the fall prevention guide 19 is disposed on the opposite side of the work guide 15 with respect to the revolution arcuate route of the workpiece 9 with the work stopper 17 interposed therebetween. The work stopper 17 is for preventing the workpiece 9 from coming out of the storage pocket 11 to the left and right and falling downward while the carrier 7 is rotating, and along the annular curve of the carrier 7. It is configured in an arc. The discharge chute 21 receives and collects the workpiece 9 that has been ground. The discharge chute 21 is disposed in the vicinity of the terminal end of the fall prevention guide 19, and in the present embodiment, is disposed on the lower side (rotation center CL) near the uppermost portion of the carrier 7. In the present embodiment, since the rotation center CL of the carrier 7 is oriented not in the vertical direction but in the horizontal direction, the workpiece 9 is recovered in the discharge chute 21 by dropping due to its own weight. It is not limited to the collection mode and can be modified as appropriate.

  The relationship of the rotation direction of each part is shown as an example. In FIG. 1, arrows indicated by reference signs A, B, C, and D indicate the rotation directions of the grinding wheel 5, the workpiece 9, the carrier 7, and the adjustment wheel 3 during the grinding operation, respectively. That is, in the present embodiment, the rotation direction A of the grinding wheel 5 and the rotation direction B of the workpiece 9 are clockwise when viewed in the plane of FIG. 1, and the rotation direction of the carrier 7 (the revolution direction of the revolution arcuate route). ) C and the rotation direction D of the adjusting wheel 3 are counterclockwise when viewed toward the plane of FIG. Therefore, the rotation direction A of the grinding wheel 5 is the same direction as the rotation direction B of the workpiece 9 and is opposite to the revolution direction of the revolution arcuate route. In addition, in relation to the rotation direction C of the carrier 7, each accommodation pocket 11 of the carrier 7 is formed with a predetermined inclination. Each of the storage pockets 11 is inclined so that the inner peripheral side of the carrier 7 is displaced forward than the outer peripheral side as the carrier 7 rotates.

  According to the centerless grinding apparatus having the above-described configuration, the adjusting wheel 3 and the grinding wheel 5 are arranged so that the arc-shaped convex side and the arc-shaped concave side face each other, and the object 9 to be ground is disposed on the arc-shaped convex side. Grinding is performed on a revolving arcuate route arranged so as to pass between the arcuate concave side and the arcuate concave side. For this reason, compared with the aspect in which the adjusting wheel and the grinding wheel are arranged in a relationship in which the arc-shaped convex sides face each other as in the existing centerless grinding apparatus, in the present invention, the object to be ground is conveyed in the conveyance path of the object 9 to be ground. A long contact area between the object 9 and the grinding wheel 5 and the adjustment wheel 3 can be secured. Therefore, in the present invention, when the grinding amount and the conveyance speed of the workpiece are the same, the grinding can be performed more slowly than the existing mode (the grinding amount per conveyance distance of the workpiece can be reduced), As a result, it has become possible to greatly suppress cracks and chips generated in the workpiece during grinding. Depending on the needs, the grinding amount per conveyance distance of the work piece is set to an existing level, and the present invention is implemented so that the adjustment wheel and the grinding wheel (and the centerless grinding device as a whole) can be miniaturized. It would also be possible.

  In particular, as in the present embodiment, when the arcuate concave side of the adjustment arcuate part 3a and the arcuate convex side of the grinding arcuate part 5a face each other, that is, the grinding wheel 5 is the center of revolution in the arcuate arcuate route. In the case of being arranged on the (rotation center CL) side, the following excellent advantages are obtained in addition to the above. First, as a background, the core of a winding component used as an electronic component is extremely small. For this reason, a highly accurate grinding aspect is required. In addition, the core constituting the electronic component has a high need for mass production, and it is desirable to promote the downsizing of individual devices and to effectively utilize the limited manufacturing facility space to realize efficient production. In this regard, according to the present embodiment, grinding can be performed sufficiently even when the diameter of the grinding wheel is reduced, by grinding inside the arc of the route traveling in an arc shape. Further, by reducing the diameter of the grinding wheel, i) it is possible to suppress the deflection even if a thin disk-shaped grinding wheel is used, and a highly accurate grinding result can be obtained, and ii) the grinding wheel As a result, the device can be made more compact. In addition, according to the inventor's research, when a workpiece to be ground made of ferrite is ground using the outer peripheral side of the adjusting wheel and the outer peripheral side of the grinding wheel, the core cutting angle (loading angle) to the workpiece is ground. ) Is large, and cracking or chipping may occur during loading. On the other hand, according to the present embodiment, the object to be rotated is revolved in an arc shape, and grinding is performed from the inside of the arc shape, thereby suppressing a cutting angle and an impact on the object to be ground to be small. It is possible.

  Furthermore, in this embodiment, since both the grinding wheel and the carrier are arranged inside the annular shape of the adjustment wheel, all of the adjustment wheel, the grinding wheel, and the carrier can be arranged only by the space occupied by the adjustment wheel. It is possible to proceed with significant downsizing.

  Although the contents of the present invention have been specifically described with reference to the preferred embodiments, various modifications can be made by those skilled in the art based on the basic technical idea and teachings of the present invention. It is self-explanatory.

  The adjusting means and the grinding means in the present invention are arranged such that one arcuate convex side and the other arcuate concave side of the adjusting arcuate part and the grinding arcuate part face each other. As one specific example, FIG. The configuration is listed. Furthermore, the modified form shown in FIG. 4 is also possible as another specific example.

  In this embodiment, as shown in FIG. 4, the centerless grinding apparatus 101 is configured such that the adjustment wheel 103 and the grinding wheel 105 are in a relationship in which the arc-shaped convex side of the adjustment arc-shaped portion 103 a and the arc-shaped concave side of the grinding arc-shaped portion 105 a face each other. Is arranged. A carrier 107 is provided between the arcuate convex side of the adjustment arcuate part 103a and the arcuate concave side of the grinding arcuate part 105a. The object to be ground is ground on a revolving arcuate route arranged so as to pass between the arcuate convex side and the arcuate concave side. Further, both the adjusting wheel 103 and the carrier 107 are disposed inside the annular grinding wheel 105. Also according to this form, it can grind more gently than the existing aspect, and the crack and chip | tip which arise in the to-be-ground thing at the time of grinding can be suppressed significantly. In addition, all of the adjustment wheel, grinding wheel, and carrier can be arranged only by the space occupied by the grinding wheel, and the apparatus can be greatly downsized.

  In addition, the adjustment means and the grinding means need only be arranged so that one arcuate convex side and the other arcuate concave side of the adjustment arcuate part and the grinding arcuate part face each other. It is not limited to a circular shape or an annular shape. That is, the adjustment arc-shaped portion and / or the grinding arc-shaped portion may be present in at least a part of the adjustment means and / or the grinding means. A specific example of this form is shown in FIG.

  In this embodiment, as shown in FIG. 5, the centerless grinding apparatus 201 is configured such that the adjustment wheel 203 and the grinding wheel 205 are in a relationship in which the arc-shaped concave side of the adjustment arc-shaped portion 203 a and the arc-shaped convex side of the grinding arc-shaped portion 205 a face each other. Is arranged. In this example, the adjustment arc-shaped portion 203 a is partially present in the adjustment wheel 203. A carrier 207 is inserted between the arcuate concave side of the adjustment arcuate part 203a and the arcuate convex side of the grinding arcuate part 205a. The object to be ground is ground on a revolving arcuate route arranged so as to pass between the arcuate convex side and the arcuate concave side. Also according to this form, it can grind more gently than the existing aspect, and the crack and chip | tip which arise in the to-be-ground thing at the time of grinding can be suppressed significantly. In this example, the relationship between the adjusting wheel and the grinding wheel in FIG. 5 can be reversed, and the grinding wheel can be partially provided with a grinding arc portion.

  Moreover, the adjustment means of this invention should just adjust the autorotation aspect of a to-be-ground object, and is not limited to the form which surrounds the substantially outer periphery of a conveyance means. You may exist only in the part along the revolution arcuate route in a conveyance means. FIG. 5 is a specific example thereof.

  The adjusting means is not limited to being movable, and adjusts the rotation mode of the object to be ground based on a relative speed difference with the conveying means that is moving for conveying the object to be ground. It is also possible to make the stationary one function as the adjusting means by changing the moving speed of the conveying means.

  The conveying means may be any means as long as it can advance the object to be ground along an arcuate route, and is not limited to an annular shape. That is, if there is an arc-shaped portion in a part of the annular shape, the entire conveying means need not be in the form of a ring. FIG. 5 is a specific example thereof. Moreover, what is necessary is just to be able to support and guide a to-be-ground thing so that rotation is possible, and as above-mentioned, it is not limited to the aspect of a pocket.

  Further, the adjusting means and the conveying means are not necessarily limited to being in contact with the object to be ground, that is, as long as they can be rotated in an arc shape while finally rotating the object to be ground. It may function in a contact mode.

  The respective rotation directions (traveling directions) of the grinding means, the object to be ground, the conveying means, and the adjusting means can be appropriately changed.

1, 101, 201 Centerless grinding device 3, 103, 203 Adjusting wheel 5, 105, 205 Grinding wheel 7, 107, 207 Carrier 9 Workpiece

Claims (3)

An adjusting means for rotating the workpiece,
A grinding means that is rotatably supported and grinds an object to be ground;
A conveying means disposed between the adjusting means and the grinding means, supporting each of the objects to be ground so as to be capable of rotating, and guiding and advancing a plurality of objects to be ground along a revolving arcuate route;
The adjusting means and the grinding means each have an adjusting arc-shaped portion and a grinding arc-shaped portion,
The adjustment arc-shaped portion and the grinding arc-shaped portion are arranged so that the arc-shaped convex side and the arc-shaped concave side face each other,
The revolution arcuate route is a centerless grinding device arranged to pass between an arcuate convex side and an arcuate concave side. The centerless grinding apparatus according to claim 1, wherein the grinding means is disposed on a revolution center side of the revolution arcuate route. The adjusting means is an adjusting wheel configured in an annular shape,
The grinding means has a smaller diameter than the adjusting wheel,
The centerless grinding apparatus according to claim 2, wherein both the grinding means and the conveying means are arranged inside the adjustment means on the annular side.

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