JP2018153819A - Countersinking mold and countersinking method using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mold that reduces distortion generated in a workpiece by countersinking, and a countersinking method using the same.SOLUTION: A mold according to an embodiment of the present invention is a mold for countersinking a workpiece. The mold comprises a punch that has an approximately cylindrical functional part in a lower part and the functional part of which has its tip provided with a tapered part narrowed on the basis of a countersinking angle, and a die in which a depressed part opened on a top surface and spread in a tapered shape toward the top surface is formed.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a mold for dish fir processing and a dish fir processing method using the same.

  Currently, dish fir processing is generally performed on workpieces such as sheet metal using a punching machine such as a turret punch press. In conventional dish fir processing, for example, a punch having a tapered portion at the tip is prepared, and the tapered portion of the punch is pressed against the periphery of a prepared hole formed in the workpiece. As a result, the side surface of the pilot hole is deformed into a taper shape to form a countersink that receives the head of the countersunk screw. However, in the case of this method, there is a problem in that the material of the peripheral portion of the pilot hole spreads outward due to the pressing of the tapered portion of the punch, and as a result, the workpiece is distorted.

Sho 52-132490

  Therefore, the present invention provides a mold for reducing distortion generated in a workpiece by dish fir processing and a dish fir processing method using the mold.

  The metal mold | die which concerns on embodiment of this invention is a metal mold | die which carries out dish fir processing with respect to a workpiece | work, and has a substantially cylindrical functional part in the lower part, The said functional part is based on the angle of a dish fir in the front-end | tip. It is characterized by comprising a punch having a taper portion that narrows, and a die that has an opening on the top surface and a recess portion that expands in a taper shape toward the top surface.

  A dish fir processing method according to an embodiment of the present invention is a dish fir processing method for a workpiece using the mold, wherein a first hole is formed with respect to a processing position of the workpiece, and the die is recessed. After the workpiece is placed on the die so that the processing position of the workpiece matches the portion, the taper portion of the punch is pressed against the first hole and the peripheral edge thereof, and the peripheral material of the first hole is changed to the peripheral material of the first hole. Extruding into the recessed part of the die, forming a second hole having a diameter larger than the first hole with respect to the processing position of the workpiece, and dropping the peripheral material of the first hole extruded into the recessed part of the die It is characterized by that.

  ADVANTAGE OF THE INVENTION According to this invention, the metal mold | die which reduces the distortion which arises in a workpiece | work by dish fir processing, and the dish fir processing method using the same can be provided.

It is a whole lineblock diagram of an example of a press machine concerning an embodiment of the present invention. It is a front view of the metal mold for dish fir processing concerning the embodiment. It is an enlarged view of the metal mold | die for dish fir processing concerning the embodiment. It is the schematic explaining the process of the dish fir processing method concerning the embodiment. It is the schematic explaining the process of the dish fir processing method concerning the embodiment. It is the schematic explaining the process of the dish fir processing method concerning the embodiment. It is the schematic explaining the process of the dish fir processing method concerning the embodiment. It is a figure explaining the outline | summary of the metal mold | die for dish fir processing which concerns on the modification of the embodiment. It is a figure explaining the outline | summary of the metal mold | die for dish fir processing concerning the modification. It is the schematic explaining the process of the dish fir processing method which concerns on the comparative example with respect to the embodiment.

  DESCRIPTION OF EMBODIMENTS Hereinafter, a dish for fraying processing according to an embodiment of the present invention and a method for bending the same will be described with reference to the drawings. In addition, although the dish fir processing method of this embodiment is applicable to the press machine at large, the example applied to the turret punch press 1 below is demonstrated.

First, an outline of the turret punch press 1 used in the dish fir processing method will be described.
FIG. 1 is an overall configuration diagram of a turret punch press according to an embodiment of the present invention.
The turret punch press 1 includes a work table 10, a processing unit 20, a control unit 40, and an operation unit 50.
The work table 10 has a table body 11 in which a plurality of table units 12 are arranged. Each table unit 12 is constituted by, for example, a board 13 and a plurality of brushes 14 arranged on the upper surface of the board 13 and arranged at the same height. The work table 10 has legs 15 that support the table body 11. The leg 15 is connected to the processing unit 20 and is configured by a combination of a plurality of frames.

  The processing unit 20 includes an upper turret 21U, a lower turret (not shown) disposed below the upper turret 21U, and an arch portion 23 that supports the upper turret 21U from above. The upper turret 21U has a plurality of stations 22 for mounting the punches of the mold T, and one of the plurality of punches is selected as the turret 21U rotates. Similarly, the lower turret has a plurality of stations for mounting the die of the mold T, and one of the plurality of dies is selected by rotating the lower turret. Hereinafter, the upper turret 21U and the lower turret are simply referred to as “turret 21”. The processing unit 20 includes a carriage 24 supported by the arch portion 23 and a plurality of clamps 25 supported by the carriage 24. The plurality of clamps 25 can grip the workpiece W in the thickness direction. Here, the carriage 24 is configured to be movable in the Y direction, which is the extending direction of the arch portion 23. Further, the plurality of clamps 25 are configured to be movable in the X direction, which is the extending direction of the carriage 24, while being synchronized with each other. Therefore, each clamp 25 can move two-dimensionally in the horizontal direction on the pass line of the work table 10 while sandwiching the work W.

  Further, the processing unit 20 includes a press driving unit 26 in the arch portion 23. The press drive unit 26 moves the striker 27 that pushes the punch of the mold T up and down. Thereby, the press operation using the selected mold T is realized. In the example of FIG. 1, the press drive unit 26 converts the rotary motion of the motor 28 into the vertical motion of the striker 27 by the link mechanism 29.

The control unit 40 controls the overall operation of the turret punch press 1. Specifically, the rotation of the turret 21, the raising and lowering of the mold T attached to the turret 21, the movement of the carriage 24 in the Y direction, the movement of the plurality of clamps 25 in the X axis direction, and the like are controlled.
The operation unit 50 includes an image display unit 51 and various buttons 52. The operator gives instructions to the turret punch press 1 by operating various buttons 52.

Next, the metal mold | die T used with the dish fir processing method of this embodiment is demonstrated.
The dish fir processing method of the present embodiment includes three steps of pilot hole processing, chamfering processing, and finishing processing described later. Different molds T are used in each process. Of these, as the molds 100 and 300 used in the pilot hole machining and the finishing machining, general circular hole punching molds can be used, and thus the description thereof is omitted here. On the other hand, in the chamfering process, the following mold 200 for dish fir processing is used.

  FIG. 2 is a front view of a mold for dish fir processing according to the present embodiment, and FIG. 3 is an enlarged view of a functional portion of a punch of the mold and a die upper surface described later. FIG. 2 also shows the workpiece W.

The die 200 (T in FIG. 1) is a die that presses and expands the peripheral portion of the through-hole Wh of the workpiece W formed by pilot hole processing in a tapered shape, and includes a die 210 and a punch 250.
The die 210 has a substantially cylindrical shape as a whole, and a recessed portion 211 is formed on the upper surface, for example, near the center. The recessed portion 211 is open on the upper surface of the die 210 and expands in a tapered shape as it goes to the upper surface. The recessed portion 211 has an opening angle θd of, for example, 60 to 90 ° (60 ° in the case of FIG. 3).

  The punch 250 has a cylindrical punch guide 251 supported by a punch holder (not shown) of the turret punch press 1 so as to be movable up and down. A punch plate 252 that presses the workpiece W in cooperation with the die 210 is attached to the lower end of the punch guide 251 by straight pins 254 and bolts 255 with holes. In the vicinity of the center of the punch plate 252, a through hole 253 for inserting a functional portion 260 described later is formed. On the other hand, a retainer collar 256 is detachably disposed at the upper end of the punch guide 251.

  A punch body 257 is fitted in the punch guide 251 so as to be movable up and down. The punch body 257 includes a head connecting portion 258, a retaining portion 259, and a functional portion 260 that are integrally formed. The head connecting portion 258 is disposed on the upper side of the retaining portion 259, and the punch head 263 is screwed to the upper end thereof. The retaining portion 259 has a substantially cylindrical shape having a thickness approximately equal to the inner diameter of the punch guide 251 and is configured not to pass through the through hole 253 of the punch plate 252. The functional portion 260 is disposed below the retaining portion 259. The functional portion 260 is substantially cylindrical and has a diameter that allows the through hole 253 of the punch plate 252 to be inserted. A tapered portion 261 is formed at the lower end of the functional portion 260. As shown in FIG. 3, the tapered portion 261 narrows toward the tip end surface 262 at an angle of a dish fir to be formed, for example, θp1 = 90 °. In addition, although the front end surface 262 of the functional part 260 may be flat, as shown in FIG. In this case, the lower end of the tapered portion 261 that is the cutting edge of the punch 250 has a substantially triangular cross section. Since this tapered portion 261 requires a certain degree of strength, it is desirable that the recess of the front end surface 262 be formed with an opening angle θp2 of about 60 to 90 ° (70 ° in the case of FIG. 3).

  Further, a stripping spring 266 is mounted between the retainer collar 256 and the punch head 263 via a spacer 264 and a punch head collar 265. Thus, the punch body 257 is normally pulled up, and the bottom surface of the retaining portion 259 of the punch body 257 is in a state separated from the top surface of the punch plate 252. When the striker 27 (not shown in FIG. 2) pushes down the punch body 257, the bottom surface of the retaining portion 259 comes into contact with the top surface of the punch plate 252 as shown in FIG. As a result, the workpiece W placed on the die 210 is pressed and securely fixed to the mold 200. Moreover, damage to the mold 200 and the workpiece W due to excessive lowering of the functional part 260 can be avoided.

Next, the dish fir processing method of this embodiment using the mold 200 for dish fir processing will be described.
4-7 is the schematic explaining the process of the dish fir processing method which concerns on this embodiment. Here, as an example, a dish fir with an upper end diameter of 10 mm and a lower end diameter of 8.25 mm is processed.

  First, as step S101, pilot hole machining is performed on a desired machining position of the workpiece W (FIG. 4). A mold 100 (T in FIG. 1) used in step S <b> 101 is for punching a circular hole with respect to the workpiece W, and includes a die 110 and a punch 150. The punch body 157 of the punch 150 has a substantially cylindrical functional portion 160 at a lower portion thereof. The outer diameter φp of the functional portion 160 is determined by a desired diameter of the prepared hole, and is smaller than the diameter of the lower end of the dish fir. Here, φp = 7.5 mm, which is smaller than the diameter 8.25 mm at the bottom of the dish fir. In this step S101, a through hole Wh ″ (first hole) having a diameter of 7.5 mm that serves as a pilot hole for the workpiece W is formed by a pressing operation using the mold 100.

  Subsequently, as step S102, a chamfering process is performed on the workpiece W. Here, the side surface of the through hole Wh ″ is deformed into a taper shape by using a mold 200 for dish fir processing. Note that the outer diameter φc1 of the functional part 260 of the mold 200 used in step S102 is equal to or larger than the diameter of the upper end of the dish fir. In addition, the diameter φc2 of the front end surface 262 of the functional part 260 is equal to or smaller than the diameter of the lower end of the dish fir. That is, the diameter of the lower end of the dish fir is 8.25 mm or less. Therefore, the diameter of the through hole Wh ″, that is, the pilot hole is smaller than the outer diameter φc1 of the functional portion 260.

  In this step S102, first, as shown in FIG. 5, the workpiece W is placed on the die 210 of the mold 200 so that the processing position of the through hole Wh ″ matches the position of the recessed portion 211. Thereafter, when the punch 250 is lowered, the workpiece W is pressed by the punch plate 252 and fixed on the die 210. At this time, the punch body 257 is still pushed up by a stripping spring 266 (not shown). Next, the punch body 257 is lowered (white arrow a101 in FIG. 5), and the tapered portion 261 of the functional portion 260 is pressed against the peripheral portion We of the through hole Wh ″. As a result, as shown in FIG. 6, the peripheral portion We of the through hole Wh ″ is deformed to form a taper that matches the angle of the dish fir. Here, the through hole (second hole) after deformation is indicated by Wh ′. At this time, unnecessary material Wm of the peripheral portion We (hereinafter, also referred to as “peripheral material Wm”) is pushed out into the recessed portion 211 of the die 210 (open arrow a102 in FIG. 6). Here, in order to make it easier to push the peripheral material Wm into the recessed portion 211, it is desirable that the diameter of the through hole Wh ″ formed in step S101 is small to some extent. For example, as shown in FIG. 5, the diameter of the through hole Wh ″ may be smaller than the outer diameter φc <b> 2 of the tip surface 262 of the functional part 260.

Finally, as step S103, finishing processing for the workpiece W is executed (FIG. 7). A mold 300 (T in FIG. 1) used in step S <b> 103 is for punching a circular hole with respect to the workpiece W, and includes a die 310 and a punch 350. A punch body 357 of the punch 350 has a substantially cylindrical functional portion 360 at a lower portion thereof. The outer diameter φf of the functional part 360 is the same as the lower end of the dish fir. That is, the diameter of the lower end of the dish fir is 8.25 mm. In this step S103, a through hole Wh having a diameter of 8.25 is further formed at the machining position of the through hole Wh ′ of the workpiece W by a press operation using the mold 300. At this time, the unnecessary peripheral material Wm pushed out to the inside of the through hole Wh ′ is cut off. Thus, the processing of the dish fir with the upper end diameter of 10 mm and the lower end diameter of 8.25 mm with respect to the workpiece W is completed.
The above is the dish fir processing method of this embodiment.

  Next, effects of the mold 200 of the present embodiment and the dish fir processing method using the mold 200 will be described. Here, as a comparative example, a dish fir processing method using a mold 400 shown in FIG. 10 instead of the mold 200 is used.

  The mold 400 of the comparative example (T in FIG. 1) is different from the mold 200 of the present embodiment in that there is no recessed portion on the upper surface of the die 410 and the tip surface 462 of the functional portion 460 of the punch 450 is flat. ing.

  Even when the mold 400 is used in step S102, the through hole Wh ″ having the tapered peripheral portion We can be formed. However, in the case of the mold 400, the peripheral material Wm that does not have a recessed portion formed in the die 410 and has no escape space is downward in the radial direction of the through-hole Wh ″ as indicated by the white arrow a201 in FIG. It will be rushed. As a result, the work W is distorted. In particular, when the workpiece W is a stainless steel plate, the tendency becomes strong. In this regard, in the case of the present embodiment, since the recessed portion 211 is formed in the die 210 of the mold 200, the peripheral material Wm can be released to the recessed portion 211. As a result, distortion generated in the workpiece W can be reduced as compared with the comparative example.

  Moreover, if the front end surface 262 of the functional part 260 is recessed like the mold 200, the front end of the tapered part 261 becomes sharp. In this case, the tip of the taper portion 261 not only easily bites into the peripheral portion We of the workpiece W, but also the peripheral material Wm is more easily drawn inward. That is, if this tip end surface 262 is recessed, the effect of reducing the distortion of the workpiece W can be further obtained.

  Here, reference will be made to possible adverse effects when the die 210 has the recessed portion 211. This can occur when the mold T is switched when the process proceeds from step S102 to step S103. That is, in order to switch the mold T from 200 to 300, it is generally necessary to rotate the turret 21 while the work W is fixed, or to move the work W to the position of the mold 300. And if the peripheral material Wm of the workpiece | work W is caught in the recessed part 211 of the die | dye 210 after step S102, the rotation of the turret 21 or the movement of the workpiece | work W cannot be performed smoothly. However, in the case of the mold 200 of the present embodiment, the recessed portion 211 is formed in a tapered shape that expands toward the upper surface of the die 210. Therefore, the peripheral material Wm is hardly caught on the recessed portion 211, and the workpiece W is easily detached from the recessed portion 211, so that the above-described problems are hardly caused.

This problem can also be solved by a mold 500 as described below, for example.
8 and 9 are views for explaining the outline of a mold for processing dish fir according to a modification of the present embodiment.
This mold 500 (T in FIG. 1) is constituted by a die 510 and a punch 550. Among these, the punch 550 is the same as the punch 250 of the mold 200. On the other hand, unlike the die 210 of the mold 200, the die 510 has a push-up mechanism that raises the bottom surface of the recessed portion 511. Specifically, as shown in FIGS. 8 and 9, a counter 512 capable of moving up and down is provided at the bottom of the recessed portion 511.

  When step S <b> 102 is performed using this mold 500, the peripheral material Wm of the workpiece W enters the inside of the recessed portion 511 of the die 510 as shown in FIG. 8. However, as shown in FIG. 9, after the punch 550 is raised (the white arrow a301 in FIG. 9), if the counter 512 is raised (the white arrow a302 in FIG. 9), the workpiece W becomes a recessed portion. 511 is pushed up from within. As a result, the peripheral material Wm can be prevented from being caught with respect to the recessed portion 511. That is, smooth movement of the workpiece W can be realized by using the push-up mechanism even when the concave portion of the upper surface of the die is not tapered like the mold 200.

  In other words, according to the present embodiment, it is possible to provide a mold in which distortion generated in a workpiece due to dish fir processing is reduced and a dish fir processing method using the mold.

  As mentioned above, although embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 1 ... Turret punch press, 10 ... Work table, 11 ... Table main body, 12 ... Table unit, 13 ... Board, 14 ... Brush, 15 ... Leg, 20 ... Processing part, 21 ... Turret, 21U ... Upper turret, 22 ... Station, 23 ... Arch part, 24 ... Carriage, 25 ... Clamp, 26 ... Press drive part, 27 ... striker, 28 ... motor, 29 ... link mechanism, 40 ... control unit, 50 ... operation unit, 51 ... image display unit, 52 ... button, 100, 200 , 300, 400, 500 ... Die, 110, 210, 310, 410, 510 ... Die, 150, 250, 350, 450, 550 ... Punch, 157, 257, 357 ... Punch body , 160 260, 360, 460... Functional part, 211, 511 .. recessed part, 251... Punch guide, 252 .. punch plate, 253 .. through hole, 254. .... Bolts with holes, 256 ... Retainer collar, 258 ... Head connection part, 259 ... Retaining part, 261 ... Taper part, 262, 462 ... Tip surface, 263 ... Punch Head, 264 ... Spacer, 265 ... Punch head collar, 266 ... Stripping spring, 512 ... Counter, T ... Mold, W ... Workpiece, We ... Peripheral part, Wh, Wh ′, Wh ″... Through hole, Wm.

Claims (11)

A mold for filing a dish against a workpiece,
A punch having a substantially cylindrical functional part at the lower part, the functional part having a tapered part narrowing based on the angle of the dish fir at the tip,
A die for dish fir processing, comprising: a die having an opening on an upper surface and a concave portion extending in a taper shape toward the upper surface. A mold for filing a dish against a workpiece,
A punch having a substantially cylindrical functional part at the lower part, the functional part having a tapered part narrowing based on the angle of the dish fir at the tip, and the tip surface being recessed;
A mold for dish fir processing, comprising: a die having a recess portion formed in an upper surface. The die according to claim 2, wherein a front end surface of the punch is recessed in a substantially hemispherical shape. The mold according to claim 3, wherein the depression on the tip surface of the punch has an opening angle of 60 to 90 °. The die according to any one of claims 2 to 4, wherein the recessed portion of the die expands in a tapered shape as it goes to the upper surface of the die. The mold according to claim 1 or 5, wherein the recessed portion of the die has an opening angle of 60 to 90 °. The die according to any one of claims 1 to 6, wherein the die has a push-up mechanism in which a bottom surface of the recessed portion rises. It is a dish fir processing method with respect to the workpiece | work using the metal mold | die of any one of Claims 1-7,
Forming a first hole with respect to the machining position of the workpiece;
After placing the workpiece on the die so that the machining position of the workpiece matches the recessed portion of the die, the tapered portion of the punch is pressed against the first hole and the periphery thereof, Extrude peripheral material into the recessed part of the die,
A dish fir formed by forming a second hole having a diameter larger than that of the first hole with respect to a machining position of the workpiece and dropping the peripheral material of the first hole pushed into the recessed portion of the die. Processing method. The dish fir processing method according to claim 8, wherein the first hole has a diameter smaller than an outer diameter of a functional part of the punch. The dish fir processing method according to claim 8 or 9, wherein the first hole has a diameter smaller than a tip end surface of the punch. The dish fir processing method according to any one of claims 8 to 10, wherein the second hole has a diameter that is smaller than an outer diameter of a functional part of the punch and larger than a tip end surface of the punch. .

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