JP2006255778A - Method for simultaneously heading-forming washer and bolt - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for simultaneously performing the heading of a washer and a bolt with a head part which can be mutually fitted to each other with consistency from one piece of a bar-like blank without developing any scrap. <P>SOLUTION: In the simultaneous heading method, the heading of a washer D and a bolt G are performed with consistency from one piece of metal-made round bar-like blank B with a multi-step type heading machine without developing any scrap. In a first process S1, the blank B is punching-worked into a prescribed shape to integrally form a disk part C1 and a round columnar part C2, and in a second process S2, the round columnar part is pushed out and cut off into the annular washer D and a columnar body E to firstly form the washer D. Thereafter, there is performed the heading of the bolt G having a prescribed-shaped head part G1 at one end part of punched-out columnar body E in the second process S2 and providing a shaft part G2 for forming screw suitable to the hole diameter D1 of the above washer D. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for simultaneously forging a washer and a bolt, which simultaneously forges a washer and a bolt from one blank obtained by cutting a metal round bar into a predetermined size without scraping.

  Conventionally, the washer is formed by punching from a metal plate, and the bolt is individually formed by multi-stage forging from a blank obtained by cutting a round bar into a predetermined size.

Problems to be solved by the invention

  However, according to the manufacturing method described above, when forming an annular washer from a metal plate by punching, there is a problem in that the remaining punched part becomes a punching waste, resulting in wasted material, and the washer and bolt Since these were manufactured individually, they could not be manufactured consistently and efficiently, resulting in high costs.

  Therefore, the present invention provides a method for simultaneously forging a washer and a bolt, which can simultaneously form a washer and a bolt of a desired shape that can be fitted to each other from a single bar-like material, simultaneously and without scrap. This is the issue.

Means for solving the problem

  In order to solve the above-mentioned problem, the invention according to claim 1 of the present invention is a multi-stage forging machine that combines a washer and a bolt from a single blank obtained by cutting a metal round bar into a predetermined size. In the first step, the blank is punched into a desired shape and the disc portion and the cylindrical portion are integrally formed. The cylindrical part is punched in two steps and divided into an annular washer and a cylindrical body to form a washer first, and then a predetermined washer is attached to one end of the cylindrical body punched in the second process in the subsequent processes. A bolt including a head portion having a seating surface to be fitted and a screw-forming shaft portion adapted to the hole diameter of the washer is forged.

  Further, in the second aspect of the invention, in the case of the first aspect of the invention, when the metal round bar is a metal that is hardened by metal work such as iron or steel, it is punched in the second step. The cylinder body is inverted 180 ° and transferred to the third step, and a head pre-formation is performed at the end opposite to the punched side where the metal working hardening of the cylinder occurred in the third step. After that, in the subsequent processes, the preliminary head is made to have a predetermined size and shape, and finish forging and shaft drawing are performed so that the cylindrical body has a predetermined size and shape. To do.

  Further, in the invention described in claim 3, in the invention described in claim 1, the cylindrical body punched out in the second step is directly transferred in parallel to the third step, and the cylindrical body is punched out in the third step. The head is pre-formed to form a preliminary head in which the hardened metal work that occurred during punching is diffused to the top surface at the end, and then the center of the top surface of the preliminary head in the subsequent steps. It is characterized in that a square hole for a jig is formed.

  According to a fourth aspect of the present invention, when the cylindrical portion is punched out in the second step in the first aspect of the invention and divided into an annular washer and a cylindrical body, the diameter is larger than the shaft diameter of the bolt. The cylindrical portion is punched with a piercing tool, and the punched large-diameter end and punch are received in a large-diameter hole portion of a predetermined depth provided on the entrance side of the die. To do.

  Further, the invention according to claim 5 is the cylinder of the lower surface of the disk part when the blank part is punched in the first step and the disk part and the cylinder part are integrally formed in the invention of claim 4. An annular groove having a rounded cross section is formed around the connecting portion with the portion, and a receiving portion having a recess with an outer diameter corresponding to the annular groove is formed on the upper surface of the disc portion, and the cylindrical portion is punched by punching in the second step When dividing into an annular washer and a cylindrical body, it is divided at the thin bottom portion of the annular groove portion in the disk portion.

  Of course, a finer preliminary process may be provided between the above-described processes.

The invention's effect

  According to the simultaneous forging method of a washer and a bolt according to the present invention, a washer and a bolt having a desired shape that can be fitted to each other from a single bar-shaped material can be simultaneously forged without scrap. As a result, waste of materials can be eliminated, and in addition, the washer and bolt can be simultaneously and consistently formed on a multistage forging machine, making mass production easy and miniaturizing equipment. Moreover, management of the washer and the bolt can be easily performed.

  In addition, when using a metal round bar material such as iron or steel that causes metal work hardening as a metal round bar material, the cylindrical body punched out in the second step is inverted by 180 ° and If it is configured to form a preliminary head at the end opposite to the punched side where the metal work hardening of the cylindrical body has occurred in the third step, the metal is subjected to forging of the head. It is preferable because it is possible to prevent the occurrence of problems associated with work hardening and to perform good forging.

  Also, the cylindrical body punched out in the second step is transferred in parallel to the third step as it is, and the metal work hardening portion generated at the time of punching diffuses to the top surface at the punching side end of the cylindrical body in the third step. If the head is pre-formed to form the prepared preliminary head, and then a jig square hole is formed in the center of the top surface of the preliminary head in the subsequent process, the metal work hardening Since the portion can be effectively dispersed on the top surface of the head of the bolt, it is possible to suppress an obstacle to the fastening function of the bolt, which is preferable.

  Furthermore, when punching the blank in the first step and integrally forming the disc portion and the cylindrical portion, an annular groove having a rounded cross section is formed around the connecting portion with the cylindrical portion on the lower surface of the disc portion, and When the receiving part having a recess with an outer diameter corresponding to the annular groove is formed on the upper surface of the disk part, and the cylindrical part is punched out by punching in the second step, the disk part is divided into the annular washer and the cylindrical body. If it is divided at the thin-walled bottom portion of the annular groove portion, a thin-walled portion is formed in the washer by the annular groove and the recess of the receiving portion, and it is easy to divide by the piercing tool and the center of the divided washer A thin part will remain around the hole. As a result, a reaction force can be applied to the washer by deformation of the thin wall portion when the washer is tightened by the bolt, and a loosening prevention effect of the bolt H can be expected.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 and FIG. 2 show a forging process of a washer and a bolt according to the method of the present invention. In this process, a washer and a headed bolt that can be fitted to each other from one material in a cutting process and subsequent 5 processes. It is. In that case, what is shown in FIG.1 and FIG.2 uses the metal round bar material A which metal-hardening of iron, steel, etc. generate | occur | produces as a metal round bar material. In order to make it constant, a small-diameter shaft portion having a serration that breaks at a predetermined tightening torque is formed at the tip of the bolt.

  First, in the cutting step, a continuous metal round bar A is sent intermittently from the quill tip 1 and cut with a cutter 2 across the tip 1 to obtain a cylindrical blank B.

  The blank B obtained in this manner is pushed by the cutter 2 to the immediately preceding portion of the die 3 in the first step S1 simultaneously with the cutting, and is subjected to punching by the corresponding punch 4. The die hole 3a of the die 3 has a knockout pin 5 at the bottom, the corresponding punch 4 has a circular die hole 4a on the front end surface thereof, and the blank B is simultaneously inserted into the die hole 3a of the die 3 with punching. To form a forged material C formed by integrally forming the disc portion C1 and the cylindrical portion C2.

  Next, when the forging material C is pushed out from the die 3 by the protrusion of the knockout pin 5, it is conveyed to the die 6 in the second step S2 by a transfer chuck (not shown), and the cylindrical portion C2 is punched out by the piercing tool 7 in an annular shape. The washer D is divided into the washer D and the cylindrical body E, and the washer D is first formed.

  Thereafter, the washer D is taken out from the piercing tool 7 to the outside by appropriate take-out means (not shown) as the piercing tool 7 moves backward. On the other hand, the cylindrical body E is pushed out from the die 6 by the protrusion of the knockout pin 8 and is transferred to the die 9 in the third step by the transfer chuck. In that case, the cylindrical body E punched out in the second step is inverted 180 ° and transferred to the die 9 in the third step. The cylindrical body E is punched by the corresponding punch 10 in the third step. In that case, the die hole 9a of the die 9 has a knock-out pin 11 at the bottom, and the corresponding punch 10 has a die hole 10a having a trapezoidal cross section at its front end surface. A pre-formed head F1 having a pre-head F1 is formed by forming a pre-head F1 at the end opposite to the punched-side end where the metal work hardening has occurred.

  Thereafter, the preformed bolt F is pushed out from the die 9 by the protrusion of the knockout pin 11, and it is transferred to the final die 12 by a transfer chuck. The transferred preforming bolt F is punched by the corresponding punch 13 in the fourth step. In this case, the die hole 12a with the narrowed portion of the die 12 has a knockout pin 14 at the bottom, and the corresponding punch 13 has a shallow bowl-shaped die hole 13a at the front end surface. The preformed bolt F having the head portion F1 is subjected to finish forging and shaft drawing processing, and has a screw forming shaft portion G1 adapted to the hole diameter of the washer D and a shallow bowl-shaped head portion G2 at the base end portion thereof. Bolt G is formed. In that case, a small-diameter shaft portion G3 is formed at the tip of the screw forming shaft portion G1.

  Thereafter, the bolt G is pushed out of the die 9 by the protrusion of the knockout pin 11, and it is transferred to the die 12 in the fifth step by the transfer chuck. The transferred preliminary bolt G is punched by the corresponding punch 15 in the fifth step, and serrations are formed on the outer periphery of the small diameter shaft portion G3 at the tip of the screw forming shaft portion G1 together with finish forging. Thus, a bolt H having a small diameter shaft portion H3 having a serration formed at the tip and having a screw forming shaft portion H1 and a head portion H2 is formed. Thereby, the bolt H and the washer D can be consistently forged from one blank B without scrap. In addition, although not shown in the drawing, the screw forming shaft H1 is continuously formed by screw rolling in subsequent steps.

  As described above, according to the simultaneous forging method of the washer and the bolt, the washer D and the bolt H having a desired shape that can be fitted to each other from one blank B are simultaneously forged without scrap. be able to. As a result, waste of materials can be eliminated, and in addition, the washer D and the bolt H can be simultaneously and consistently formed by a multistage forging machine, so that mass production can be facilitated and the equipment can be downsized. In addition, the washer D and the bolt H can be easily managed.

  In the above-described embodiment, the case where a metal round bar material that causes metal work hardening such as iron or steel is used as the metal round bar material A is described. In that case, in the second step The punched cylinder is turned 180 ° and transferred to the third step, and a spare head is formed at the end opposite to the punched side where the metal processing hardening of the column E occurs in the third step. In this way, problems due to metal work hardening are not generated in the head forging.

Further, for example, when the metal round bar is a metal that does not cause metal work hardening such as lead, copper, and aluminum, or the case that the bolt fastening function by the metal work hardening is less likely to cause a failure is shown in FIG. In this way, the cylinder E ′ punched out in the second step S2 is transferred to the third step S3 as it is without reversing 180 °, and in the third step S3, a preliminary head is formed at the punched side end of the cylinder E ′. The preformed bolt F ′ may be formed by performing head preforming for forging the portion F1 ′.
Needless to say, the small-diameter shaft portion H3 provided with serrations for making the tightening torque constant at the tip of the bolt H need not be provided.

FIG. 4 shows another embodiment. In order to enable easy forging of a washer D and a bolt H with a head from a cylindrical blank B, a disk is formed in the first step S1. A connecting portion C5 that swells in a tapered shape is formed between the portion C1 and the cylindrical portion C2. In the second step S2, the connecting portion E5 is punched and divided so as to remain on the cylindrical body E side, and in the third step S4, A drum-shaped spare head F1 is formed through a connecting portion F5 that swells in a tapered shape. In the fourth step S4, the head G1, the screw-forming shaft portion G2, and the small-diameter shaft portion G3 are left with the connecting portion G5 remaining. I am trying to mold. In the fifth step S5, the serration H4 is formed on the small diameter shaft portion G3.
In this way, if it is configured so as to be formed by forging while forming a connecting portion that swells in a tapered shape, a bolt with a washer D and a head H1 from a cylindrical blank B can be suppressed while applying a large load to the die or punch. H can be formed easily without difficulty.

  Further, as the shape of the washer D, in addition to the plain washer shown in FIGS. 2 and 4, the washer (a) chamfered as shown in FIG. 5, the washer with receiving part (b), and the wedge-shaped washer (c ) Or a spherical washer with washer (d) whose bottom is inclined, or a spherical washer with a flat bottom (not shown). In that case, the bolt is also formed in an appropriate shape according to the shape of the washer as indicated by a virtual line.

  For example, when forming the washer d with the spherical receiving portion, as shown in FIG. 6, the lower surface of the head G1 of the bolt G is formed into a spherical surface with a lower outer bulge in the fourth step. In addition, the serration to the small diameter shaft part G3 and the thread rolling process to the screw forming shaft part G2 are omitted.

  7 and 8 show still another embodiment. When the blank B is punched in the first step S1 to integrally form the disc portion C1 and the column portion C2, the disc portion C1 is shown. An annular groove C3 having a rounded cross section is formed around the connecting portion with the cylindrical portion C2 on the lower surface, and a receiving portion C5 having an outer diameter recess C4 corresponding to the annular groove C3 is formed on the upper surface of the disc portion C. In the second step S2, when the cylindrical portion C is divided into the washer D with the receiving portion and the cylindrical body E by the piercing tool 7, the piercing tool 7 having a diameter larger than the shaft diameter d of the cylindrical portion C (bolt) is used. The cylindrical portion C is punched out at the thin bottom portion of the annular groove C3 in the disc portion C1. In this case, the punched large-diameter end of the cylindrical portion C and the piercing tool 7 are received in the large-diameter hole 3b having a predetermined depth provided at the entrance of the die hole 3a of the die 3.

  If comprised as mentioned above, as shown in FIG. 8, the thin part by the said annular groove D3 and the dent D4 of the receiving part 5 was formed in the washer D, and while the parting by the piercing tool 7 was easy, it was parted A thin portion remains around the central hole of the washer D. As a result, when the washer D is tightened by the bolt H, a reaction force can be applied to the washer D by the deformation of the thin portion, and the bolt H is prevented from loosening. The effect can be expected.

  Further, in this embodiment, the cylindrical body F punched in the second step S2 is transferred in parallel to the third step S3 as it is, and is generated at the punching side end of the cylindrical body E in the third step S3. The preformed head F1 is formed to form the spare head F1 in which the hardened metal work portion is diffused on the top surface. After that, in the fourth step S4, the finished forging and shaft are applied to the preformed bolt F having the spare head F1. Bolt G having a screw-forming shaft portion G2 adapted to the hole diameter of the washer D and a square head portion G2 in which a jig square hole G6 is formed at the center of the top surface at the base end portion. To form. By forming the square hole for jig in this way, the hardened metal working portion can be effectively dispersed on the top surface of the head of the bolt, so that it is possible to suppress an obstacle to the fastening function of the bolt. Note that the thread rolling process to the screw forming shaft portion G2 is omitted.

  Needless to say, in each of the above-described embodiments, a finer preliminary process may be provided between the processes.

  It is a general | schematic cross-sectional top view which shows the multistage forging part from the cutting which concerns on this invention method to forging 5 process.   It is a partially cutaway side view of the forged product in each process.   It is explanatory drawing of the principal part which shows another embodiment of a 3rd process.   It is a schematic explanatory drawing which shows embodiment of another forged product.   It is explanatory drawing of the principal part which shows another embodiment of a washer.   It is process explanatory drawing in the case of forging a spherical washer and a spherical bolt.   It is a schematic explanatory drawing which shows embodiment of another forged product.   It is an expanded sectional view of the washer.

Explanation of symbols

B Blank C1 Disk part C2 Cylindrical part C3 Annular groove C4 Recessed C5 Receiving part D1 Hole diameter D3 Annular groove D4 Recessed D5 Receiving part E Cylindrical body F Cylindrical body F1 Spare head G Bolt G1 Head G2 Screw forming shaft part G6 Angle Hole H Bolt H1 Head H2 Screw forming shaft S1 First step S2 Second step S3 Third step S4 Fourth step S5 Fifth step

Claims (5)

  A method for simultaneously forging a washer and a bolt, in which a washer and a bolt are consistently forcibly produced without scraping from a single blank obtained by cutting a metal round bar into a predetermined size without scraping. The blank is punched into a desired shape in one step, and the disc portion and the cylindrical portion are integrally formed. In the second step, the cylindrical portion is punched out and divided into an annular washer and a cylindrical body. A cylindrical body that has been formed and then punched out in the second step in the subsequent steps is provided with a head having a seating surface that fits with a washer having a predetermined shape, and conforms to the hole diameter of the washer. A method of simultaneously forging a washer and a bolt, comprising forging a bolt including a screw-forming shaft portion.   When the metal round bar is a metal that is hardened by metal work such as iron or steel, the cylinder punched out in the second step is turned 180 ° and transferred to the third step, and then the third step. The head is preformed to form a preliminary head at the end opposite to the punched-side end where the metal work hardening of the cylindrical body has occurred, and thereafter, the preliminary head has a predetermined dimension in the subsequent steps. 2. The method for simultaneously forging a washer and a bolt according to claim 1, wherein finishing forging and shaft drawing are performed so that the cylindrical body has a predetermined dimensional shape.   The cylindrical body punched out in the second step was transferred in parallel to the third step as it was, and the metal working hardened portion generated at the time of punching was diffused to the top surface at the punching side end of the cylindrical body in the third step. The head is preliminarily formed to form the preliminary head, and then a jig square hole is formed in the central portion of the top surface of the preliminary head in the subsequent steps. 2. A method for simultaneously forging a washer and a bolt according to 1.   When the cylindrical part is punched in the second step and divided into an annular washer and a cylindrical body, the cylindrical part is punched with a piercing tool having a diameter larger than the shaft diameter of the bolt, and the large-diameter end of the cylindrical part is punched. 2. The method of simultaneously forging a washer and a bolt according to claim 1, wherein the punch is received in a large-diameter hole portion having a predetermined depth provided on the entrance side of the die.   When the blank is punched in the first step and the disc portion and the cylindrical portion are integrally formed, an annular groove having a rounded cross section is formed around the connecting portion of the disc portion with the cylindrical portion on the lower surface. When a receiving part having a recess with an outer diameter corresponding to the annular groove is formed on the upper surface of the part, and the cylindrical part is punched out by punching in the second step and divided into an annular washer and a cylindrical body, the annular part in the disk part The method of simultaneous forging of a washer and a bolt according to claim 4, wherein the groove part is divided at a thin bottom portion.

Images