JP5437457B1 - Insulating spacer chamfering method - Google Patents

Abstract

An insulating spacer formed by cutting a press board is chamfered efficiently by suppressing the occurrence of fuzz as much as possible with excellent smoothness.
After arranging a plurality of insulating spacers S in a cassette 9, negative pressure is applied to each insulating spacer S to attract the insulating spacers S to the cassette 9. Next, the cassette 9 is transported, and a pair of sides facing the side perpendicular to the transport direction in the plurality of insulating spacers S are chamfered by down-cutting a pair of end mills 7 and 7 arranged apart from each other in the transport direction. .
[Selection] Figure 3

Description

  The present invention relates to a method for chamfering an insulating spacer used in an oil-filled transformer.

  Generally, the coil of an oil-filled transformer is made by winding a copper wire with a thin insulating paper of several tens of microns wound into a coil shape. In addition, between the coils and between the coil and the ground, an insulating plate formed by cutting a several millimeter thick press board corresponding to the coil, and a number of insulating plates attached to set positions on the insulating plate An insulator made of a spacer is disposed (see, for example, FIG. 8 of Patent Document 1). Specifically, the insulating spacer is cut into various shapes according to the arrangement position on the coil, but is mainly formed in a parallelogram shape with an inner angle of 45 degrees (135 degrees), and the size of the transformer Although the vertical and horizontal dimensions differ slightly depending on the type, for example, in the case of a 275,000 V transformer used for power transmission from a power plant, 50 to 60,000 pieces are used per phase.

  Here, the insulating spacer performs the function of electrical insulation and also functions as an oil flow duct that secures an appropriate flow path of insulating oil on the coil surface for cooling.

  The press board is a flat plate manufactured by overlaying wet papers made of kraft pulp fibers and pressurizing them.

JP-A-8-51036

  By the way, the insulating spacer described above is cut into a set shape and a set dimension with a saw-toothed rotary blade on the press board, but if the ridge angle at which the front and back surfaces and the cut surface intersect remains 90 degrees, the flow path of the insulating oil The resistance increases, and the function as a preset oil flow duct may be impaired, thereby reducing the cooling capacity. Further, due to the property that the press board is manufactured by overlaying and compressing wet paper, fuzz and burrs are likely to occur on the sides due to cutting. When fuzz or the like is generated on the side of the insulating spacer and peels off due to use over time, it may be mixed into the insulating oil as a foreign substance, and the filter may be clogged at an early stage. For this reason, after cutting the insulating spacer into the set shape and dimensions, the sides and vertices of the cut surface are chamfered by the operator's manual work, but this decreases the productivity of the insulating spacer and increases the cost. was there.

The present invention has been made in view of such problems, and the sides and vertices of the insulating spacer formed by cutting the press board are excellent in smoothness and suppress the occurrence of fuzz as much as possible. The present invention provides a chamfering method that can chamfer efficiently.

The present invention was adsorbed by arranging a plurality of insulating spacers formed by cutting the pressboard into the cassette, and convey the cassette, a pair of opposing the side perpendicular to the conveying direction in the plurality of insulating spacers Chamfering is performed by down-cutting a pair of end mills that are separated from each other in the conveying direction.

  According to the present invention, after arranging a plurality of insulating spacers in the cassette, a negative pressure is applied to each insulating spacer to attract the insulating spacers to the cassette. Next, a pair of end mills that transport the cassette and are arranged with a pair of sides facing each other perpendicular to the transport direction in the plurality of insulating spacers, facing sides and vertices, and a pair of facing vertices spaced apart in the transport direction. Chamfer by. At this time, if only one end mill is rotationally driven, one side or vertex on the side corresponding to the end mill is chamfered, and if both end mills are rotationally driven, a pair of opposing sides, opposing sides and A vertex and a pair of opposing vertices are chamfered.

  Here, the rotation direction, that is, the right blade and the left blade are selected so that the end mill performs a down cut based on the conveyance direction of the insulating spacer. Thereby, while being able to chamfer to a smooth cut surface, it can suppress as much as possible that fuzz and a burr | flash generate | occur | produce in the edge | side formed by chamfering.

  As a result, the sides and vertices of the insulating spacer made of the press board are excellent in smoothness and can be efficiently chamfered while suppressing the occurrence of fuzz as much as possible.

  In the present invention, when chamfering the insulating spacer by the pair of end mills, it is preferable to suck cutting waste. Thereby, while being able to prevent the working environment from deteriorating due to floating of the cutting waste, it is possible to reuse it by separating the sucked cutting waste.

  In the present invention, the cassette is formed with a recess capable of arranging a plurality of insulating spacers of a predetermined shape and size, and a plurality of intake holes are formed corresponding to each of the arranged insulating spacers, It is preferable that a rubber packing including a plurality of cutout openings is provided on the bottom surface of the recess so as to include each intake hole and support the outer peripheral edge of each insulating spacer. As a result, the plurality of insulating spacers arranged in the cassette are supported in close contact with the outer peripheral edge portions by the packing, so that when the corresponding insulating spacers are sucked through the intake holes and the cutout openings, a rough surface is obtained. The insulating spacer on the back surface can be reliably adsorbed while preventing air leakage.

  In the present invention, it is preferable that a plurality of guides having a shape corresponding to each notch opening of the packing is formed on the bottom surface of the concave portion of the cassette so as to protrude upward from the bottom surface. Thereby, when arrange | positioning packing to the recessed part bottom face of a cassette, while positioning a packing, position shift can be prevented.

According to the present invention, the sides and vertices of the insulating spacer formed by cutting the press board are excellent in smoothness and can be efficiently chamfered while suppressing the occurrence of fuzz as much as possible.

It is a top view which abbreviate | omits and shows a chamfering apparatus which implements the chamfering method of the insulation spacer of this invention. It is a front view of the chamfering apparatus of FIG. It is a perspective view of the chamfering apparatus of FIG. It is a perspective view of the cassette provided in the chamfering apparatus of FIG. It is a top view which shows the other example of the cassette of an insulating spacer. It is the top view which shows another example of the cassette of an insulating spacer, its AA sectional view, and BB sectional drawing. It is a top view which shows another example of the cassette of an insulating spacer.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  1 to 3 show an embodiment of a method for chamfering an insulating spacer according to the present invention.

  This chamfering method is executed by arranging a plurality of insulating spacers S to be chamfered on a cassette 9 fixed to the chamfering apparatus 1.

The chamfering device 1 includes a transport frame 2 that is movable in the X-axis direction (left-right direction in FIG. 1) with respect to a base (not shown), and a portal frame 3 (see FIG. 2) provided on the base. Are provided with a pair of support frames 4 (see FIG. 2) that are movable in the Y-axis direction (vertical direction in FIG. 1) with a set interval in the X-axis direction. It has been provided, et al.

  The transport frame 2 is reciprocated in the X-axis direction by an X-axis moving device provided on the base. Specifically, the X-axis moving device has a shaft center positioned in the X-axis direction of the base and the left and right ends are rotatably supported, and the screw shaft 21 is rotatably fitted. The nut member 22 and a pair of guide rails 23 arranged on the base parallel to each other with the screw shaft 21 interposed therebetween. The nut member 22 is fixed to the transport frame 2 and the pair of guide rails A pair of receiving members 24, which are movably fitted to 23, are fixed. Thereby, by rotating the servo motor connected to the screw shaft 21, the screw shaft 21 rotates around the X axis, and the nut member 22, that is, the transport frame 2 is connected to the pair of guide rails via the receiving member 24. 23 and can be reciprocated in the X-axis direction.

  Each support frame 4 is reciprocated in the Y-axis direction by a Y-axis moving device provided on the portal frame 3. This Y-axis moving device has a shaft center located in the Y-axis direction of the portal frame 3 and a screw shaft (not shown) whose front and rear ends are rotatably supported, and is rotatably fitted to the screw shaft. A nut member (not shown), and a pair of guide rails 43 disposed in parallel to the portal frame 3 with the screw shaft interposed therebetween, and the nut member is fixed to the support frame 4 A pair of receiving members 44 that are movably fitted to the pair of guide rails 43 are fixed. Thus, by rotating the servo motor connected to the screw shaft, the screw shaft rotates about the Y axis, and the nut member, that is, the support frame 4 is suspended from the pair of guide rails 43 via the receiving member 44. It can be hung and reciprocated in the Y-axis direction.

  Here, a work table 6 is fixed to the transport frame 2, and a cassette 9 on which a plurality of insulating spacers S to be processed can be arranged on the work table 6 is detachably fixed via a connecting bolt 95. An air passage (not shown) communicating with each other is formed in the transport frame 2 and the work table 6 and is set so as to communicate with an intake hole 9a formed in a cassette 9 described later. In addition, one end of an air pipe (not shown) supported to move following the movement of the transport frame 2 is connected to the air passage of the transport frame 2, and the other end of the air pipe is It is connected to a vacuum pump (not shown) provided on the base. Therefore, by driving the vacuum pump, air can be sucked through the intake holes 9a of the cassette 9, the work table 6, the air passages of the transport frame 2, and the air pipes. A negative pressure can be applied to the arranged insulating spacers S.

  On the other hand, each support frame 4 has an inclined surface 45 (see FIG. 2) parallel to the chamfered surface of the insulating spacer S, and the spindle head 5 is fixed along the inclined surface 45 of the support frame 4 so as to freely advance and retract. Has been. Therefore, by moving the spindle head 5 back and forth along the inclined surface 45 of the support frame 4, the end mill 7 detachably fixed to the spindle 51 of the spindle head 5 via the chuck can be moved in the axial direction. it can. That is, the part used for chamfering among the cutting edges of the end mill 7 can be changed, and cutting can be performed using the full length of the cutting edge.

  The direction of the cutting edge (right blade, left edge) so that the insulating spacer S is down-cut depending on the rotation direction of the end mill 7 and the conveying direction of the insulating spacer S (cutting down = cutting down the blade hits an uncut portion). Blade) is selected.

  Further, a dust collection hood 8 is provided facing the chamfered position of the insulating spacer S by the end mill 7. The dust collection hood 8 is connected to the tip of a duct 81 provided on the base so as to face the insulating spacer S that is arranged and moved in the cassette S, and has a notch 8a through which the end mill 7 can be inserted. Is formed. The dust collection hood 8 is connected to a blower (not shown) via a duct 81, and the cutting waste of the insulating spacer S generated when the end mill 7 chamfers in the dust collection hood 8 by driving the blower. Can be aspirated and pneumatically transported.

  By the way, the cassette 9 is a rectangular plate material as viewed from above, and a plurality of patterns are prepared corresponding to the chamfering target of the insulating spacer S. For example, FIG. 4 illustrates a cassette 9 in the case of chamfering a pair of opposed short sides of a parallelogram-shaped insulating spacer S having a set dimension. This cassette 9 has a plurality of times (six times) the length of the short side of the insulating spacer S so that a plurality of (six in the embodiment) insulating spacers S can be arranged in the left-right direction with the short side as the base. The two parallelogram-shaped concave portions 91 and 91 each having a horizontal dimension, a vertical dimension corresponding to the height when the short side is the bottom side, and a depth equal to or greater than the thickness of the packing 10 described later are provided in the left-right direction. It is formed apart. A plurality of (six) guides 911 protrude slightly upward from the bottom surface of the concave portions 91 of the cassette 9 at a set interval in the left-right direction according to the insulating spacers S arranged. Each guide 911 is formed with an intake hole 9a penetrating in the vertical direction.

  Here, each guide 911 is formed in a size corresponding to a notch opening 10a formed to support an outer peripheral edge portion of each insulating spacer S in a packing 10 described later, and thereby, a recess of the cassette 9 is formed. The packing 10 can be positioned on the bottom surface of 91, and can be disposed while preventing displacement.

  Further, mounting holes 9b through which the connecting bolts 95 can be inserted in the vertical direction are formed in the left and right end portions and the intermediate portion of the cassette 9 in accordance with female screws (not shown) formed in the work table 6, respectively. In addition, fitting holes 9c (see FIG. 5) that can be fitted to positioning pins (not shown) provided on the work table 6 are formed at the left and right end portions on the back surface side. For this reason, the cassette 9 can be positioned with respect to the work table 6 by fitting the fitting hole with the positioning pin of the work table 6, and the connecting bolt 95 is connected to the female screw of the work table 6 through the mounting hole 9b. The cassette 9 can be fixed to the work table 6 by screwing. At this time, each intake hole 9 a of the cassette 9 positioned and fixed to the work table 6 is communicated with the air passage of the work table 6 described above.

  On the other hand, in the left and right recesses 91 of the cassette 9, rubber packings 10 are provided that closely support and support the outer peripheral edge of the insulating spacer S. The packing 10 is formed in a parallelogram shape corresponding to each recess 91, and a plurality (six pieces) of appropriate shapes slightly smaller than the outer shape of the insulating spacer S so that the outer peripheral edge of the insulating spacer S can be supported. ) Are formed at set intervals in the left-right direction. As a result, negative pressure can be applied to the packing 10 through the air intake holes 9a and applied to portions corresponding to the notch openings 10a on the front and back surfaces of the insulating spacer S. That is, the insulating spacer S formed by cutting the press board is rough and has a rough front and back surfaces, but its outer peripheral edge is in close contact with the packing 10, thereby preventing air leakage and being reliably adsorbed.

  Next, the process of chamfering the insulating spacer S using the chamfering apparatus 1 configured as described above will be described.

  Although not shown in detail, the chamfering device 1 automatically operates according to a program incorporated in the control device based on a signal from a sensor that detects the operation status of each device, and continuously insulates the spacer S. Can be chamfered. Hereinafter, the automatic operation will be described.

  First, after inputting necessary information such as the size of the insulating spacer S to be chamfered and the amount of chamfering, the selected insulating spacer S can be arranged, and the notch opening 10a corresponding to the selected insulating spacer S is formed. A cassette 9 in which the packing 10 is arranged is prepared, and a fitting hole 9c is fitted to the positioning pin of the work table 6, and a connecting bolt 95 is screwed into the female screw of the work table 6 through the mounting hole 9b of the cassette 9. 9 is fixed to the work table 6. Next, the set number of insulating spacers S to be chamfered are sequentially arranged in the cassette 9.

  Specifically, as shown in FIG. 4, in order to chamfer a pair of opposing short sides of the parallelogram-shaped insulating spacer S, the cassette is set so that the pair of short sides opposes in the front-rear direction (Y-axis direction). Insulating spacers S are sequentially arranged in the left-right direction on the packing 10 disposed in the nine recesses 91.

  If a plurality of insulating spacers S are arranged in the cassette 9, a vacuum pump is driven by operating a start button (not shown), and each insulating spacer S arranged in the cassette 9 is passed through an air pipe, an air passage, and an intake hole 9a. A negative pressure is applied, and each insulating spacer S is adsorbed. At this time, the outer peripheral edge portion of the insulating spacer S is in close contact with the peripheral edge portion of the notch opening 10a of the packing 10 disposed in the concave portion 91 of the cassette 9, and is reliably adsorbed without air leakage due to the roughness of the front and back surfaces. To do.

When the vacuum pressure reaches the set value, each support frame 4 is moved to the set position based on the set input data of the insulating spacer S. That, Y-axis moving unit servo motor is driven rotation moves the support frame 4 to the set position, rotate the respective end mill 7 via the spindle head 5 in the rotation direction set respectively. Further, the X-axis moving device is operated to move the transport frame 2 in the X-axis direction. When the transport frame 2 reaches the chamfered position by one end mill 7, the side (short side) corresponding to the plurality of insulating spacers S is chamfered by the end mill 7 in order by down-cutting. Further, when the transport frame 2 further moves and reaches the chamfering position by the other end mill 7, the corresponding side of the plurality of insulating spacers S by the end mill 7 (the short side facing the short side that has been previously chamfered). The edges are chamfered by down-cutting in order.

  The cutting waste generated along with the chamfering of the insulating spacer S by the end mill 7 is sucked by the negative pressure acting in the dust collecting hood 8 and is pneumatically transported through the duct 81 and separated from the air through a cyclone or the like. Collected.

  Here, when chamfering the opposite sides of the insulating spacer S, the direction of the cutting edge is selected and the end mill 7 down-cuts, whereby a smooth cut surface can be obtained and the side formed by chamfering can be obtained. Generation | occurrence | production of fluff and a burr | flash can be prevented as much as possible, and abrasion of the cutting edge of the end mill 7 can be suppressed.

  Furthermore, by selecting the twist of the cutting edge of the end mill 7, it is possible to guide it downward along the twist so that the cutting waste can be sucked easily. Specifically, a right blade left-twisted end mill 7 and a left blade right-twisted end mill 7 are employed.

  When the conveyance frame 2 reaches the chamfering end positions of a pair of opposing sides of all the insulating spacers S, the servo frame is reversed to move the conveyance frame 2 to the original position. When the transport frame 2 returns to the original position, an air valve (not shown) is switched to open the air passage communicating with the intake hole 9a of the cassette 9 to the atmosphere to release the adsorption. Thereby, the insulating spacer S with a pair of opposing sides (short sides) chamfered can be taken out.

  Hereinafter, by arranging and adsorbing a plurality of insulating spacers S to be processed on the cassette 9 and chamfering a pair of opposite sides of the insulating spacer S, by repeatedly removing the chamfered insulating spacer S from the cassette, The insulating spacers S can be chamfered sequentially.

  Similarly, in order to chamfer a pair of opposing long sides of the insulating spacer S, as shown in FIG. 5, a concave portion 91 in which a plurality of insulating spacers S can be arranged with the long side positioned at the bottom is formed. At the same time, the cassette 9 in which the packing 10 having a plurality of cutout openings 10a smaller than the insulating spacer S is arranged in the work table 6 so that the outer peripheral edge of each insulating spacer S can be supported in the recess 91. Just fix it and work in the same way.

  In the above-described embodiment, the case where the pair of short sides and the pair of long sides facing each other of the parallelogram-shaped insulating spacer S are chamfered in order is exemplified, but a quadrangular shape other than the parallelogram shape, for example, a trapezoidal shape. In the insulating spacer S, it is necessary to chamfer one side at a time except for the opposite parallel sides. In this case, the cassette 9 shown in FIGS. 6 and 7 may be used.

  The cassette 9 has a lateral dimension that is a multiple of the length of one side of the chamfered object of the insulating spacer S so that the plurality of insulating spacers S can be arranged in the left-right direction with one side of the chamfered object as the base. In addition, a recess 92 is formed in which the peripheral wall on the side opposite to the side to be brought into contact with and contacted with one side of the chamfered object is removed. The bottom surface of the concave portion 92 of the cassette 9 has a plurality of set intervals in the left-right direction according to the respective notch openings 10a formed in the packing 10 so that the outer peripheral edge portions of the arranged insulating spacers S can be supported. Each guide 921 is formed to protrude slightly upward from the bottom surface, and each guide 921 is formed with an intake hole 9a penetrating in the vertical direction.

  Each guide 921 has a size and a shape corresponding to the notch opening 10a formed in the packing 10 so that the outer peripheral edge of the insulating spacer S can be supported. 10 can be positioned and positioned without displacement.

  In this way, after fixing the cassette 9 in which the packing 10 is disposed in the recess 92 to the work table 6, one side of the object to be chamfered against the inner peripheral surface of the recess 92 on the packing 10, and the insulating spacer S is moved in the horizontal direction. If the transport frame 2 is transported after being arranged in sequence, one side of the insulating spacer S to be chamfered can be chamfered in order by one end mill 7 on the corresponding side.

  By the way, if each side of the insulating spacer S is chamfered in order, the vertex at which the side intersects is automatically chamfered. Therefore, although it is not necessary to chamfer the apex again, there may be a case where only the acute angle apex on the back surface side of the insulating spacer S is chamfered, or a side opposite to the apex is chamfered together with the acute apex. In such a case, although not illustrated in detail, by preparing the cassette 9 in accordance with the chamfering target, both or one of a pair of opposing vertices of the insulating spacer S are chamfered, or between the opposing vertex and side. Both or one can be chamfered.

DESCRIPTION OF SYMBOLS 1 Chamfering apparatus 2 Conveying frame 3 Portal frame 4 Support frame 5 Spindle head 6 Work bench 7 End mill 8 Dust collection hood 9 Cassette 9a Intake hole 91, 92 Recess 911, 921 Guide 10 Packing 10a Notch opening S Insulating spacer

Claims (4)

After adsorbed by arranging a plurality of insulating spacers formed by cutting the pressboard into the cassette, and convey the cassette, a pair of opposing sides on the side perpendicular to the transport direction of the plurality of insulating spacers, to face A method for chamfering an insulating spacer, wherein chamfering is performed by down-cutting a pair of end mills that are separated from each other in the conveying direction, or both sides and vertices, a pair of opposing vertices, or one of them.   2. The insulating spacer chamfering method according to claim 1, wherein when the insulating spacer is chamfered by the pair of end mills, cutting waste is sucked.   2. The method of chamfering an insulating spacer according to claim 1, wherein the cassette is formed with a recess capable of arranging a plurality of insulating spacers having a predetermined shape and size, and a plurality of corresponding insulating spacers are arranged. In addition, a rubber packing including a plurality of notch openings is provided on the bottom surface of the recess so as to include the intake holes and support the outer peripheral edge of each insulating spacer. A method for chamfering an insulating spacer.   4. The insulating spacer chamfering method according to claim 3, wherein a plurality of guides each having a shape corresponding to each notch opening of the packing are formed on the bottom surface of the concave portion of the cassette so as to protrude upward from the bottom surface. Spacer chamfering method.

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