JP5376256B2 - Pre-tension ring, manufacturing method thereof, and two-member caulking method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To inexpensively provide a tension ring high in strength and quality by using a method of caulking two ring members hardened in a cold forging method such as pressing, without performing carburizing and quenching. <P>SOLUTION: An inner ring 2 in which a large number of halved receiving holes 21 are formed on an outer diameter part of a ring-shaped body 20 and axially projecting connection boss parts 22 are consecutively formed to an inner diameter part, and an outer ring 3 in which a large number of halved receiving holes 31, 31, ... are formed on an outer diameter part of a ring-shaped body 30 and fitting grooves 32 capable of being fitted to the connection boss parts 22 are formed on an inner diameter part, are formed by cold forging to achieve high strength, respectively. The outer ring 3 is fitted to the outer peripheries of the connection boss parts 22 of the inner ring 2, and tip portions of the connection boss parts 22 penetrating through the outer ring 3 are caulked along the outer side face of the outer ring 3, so as to integrally couple the both rings 2, 3 to each other. <P>COPYRIGHT: (C)2012,JPO&amp;INPIT

Description

  The present invention relates to a pretension ring mainly used for a seat belt retractor with a pretensioner and a method for manufacturing the same, and further relates to a two-member caulking method.

  Conventionally, in this type of seat belt retractor, a pretensioner (belt pretensioning device) that effectively winds up the belt in the event of a collision and effectively restrains the occupant's body has been added (for example, a patent) Reference 1). As one of the components of the pretensioner, a plurality of ball receiving holes 41... 41 are formed in the outer diameter portion as shown in FIG. 15 in the circumferential direction, and a spindle (not shown) is formed in the inner diameter portion. In some cases, a pretension ring 4 having a serration groove 42 to be serrated and fitted is incorporated.

As a manufacturing method of this pretension ring, since the shape is complicated, as shown in FIG. Each is formed by forging, and then these half rings 5 and 6 are integrated by welding in a state of being overlapped on the split surfaces 5a and 6a, and further plated to produce a pretension ring. I am doing so.
JP 2008-254459 A

  However, according to the manufacturing method described above, since the two half rings 5 and 6 are integrated by welding, the welded portion of the pretension ring 4 is softened by heat during welding and the strength of the ring itself is weakened. As a result, it could not be used as a pretension ring having high strength. In addition, it can be used as a high-strength pre-tensioning ring by hardening it by carburizing and quenching after welding for the problem of strength reduction. However, special equipment for carburizing and quenching is required, which requires troublesome work and a great amount of time, resulting in high costs.

  The present invention has been invented in view of the above circumstances, and its main purpose is to provide two rings that have been hard-worked and hardened by a cold forging method such as a press with a caulking method, with high strength without carburizing and quenching. The present invention provides a pretension ring that can be quickly and easily manufactured at low cost while maintaining high quality, and a method for manufacturing the same.

  Another object is not limited to the above-described pre-tension ring, and carburizing is performed when forming a high-strength and high-quality bonding member using two members that are hard-worked and hardened by a cold forging method such as a press. The present invention provides a two-member caulking method that can be quickly and easily manufactured at low cost without quenching.

  In the invention according to claim 1 of the present application, a large number of half-split holes 21... 21 for the ball are formed in the outer diameter portion of the ring-shaped main body 20 in the circumferential direction, and the connecting boss projects in the axial direction at the inner diameter portion. A half-shaped inner ring 2 in which a portion 22 is provided continuously, a fitting groove 23 is formed on the inner peripheral surface of the connecting boss portion 22, and a fitting portion 24 is formed on the outer peripheral surface; A plurality of half receiving holes 31... 31 for the ball are formed in the circumferential direction in the outer diameter portion of the inner diameter portion, and a fitting groove 32 that can be fitted in the fitting portion is formed in the inner diameter portion. The outer ring 3 is provided, and both the rings 2 and 3 are formed with high strength by cold forging, while the outer ring 3 is formed on the outer periphery of the connecting boss portion 22 of the inner ring 2 and the two half receiving holes 21. 31... Fits into the fitting portion 24 in a state where 31 faces each other. High strength by cold forging by fitting the end portion of the connecting boss portion 22 penetrating the outer ring 3 along the outer surface of the outer ring 3. Both rings 2 and 3 are integrally connected while maintaining the above.

  In the invention according to claim 2 of the present application, as a method of manufacturing a pretension ring, first, a large number of half-receiving holes 21... 21 for balls are formed in the circumferential direction on the outer diameter portion of the ring-shaped main body 20. A connecting boss portion 22 protruding in the axial direction is connected to the inner diameter portion, and a fitting groove 23 is formed on the inner peripheral surface of the connecting boss portion 22, and a fitting portion 24 is formed on the tip of the outer peripheral surface. A number of half-splitting holes 31... 31 for the ball are formed in the outer diameter of the half-shaped inner ring 2 and the ring-shaped main body 30 in the circumferential direction, and the inner diameter part is fitted to the fitting part 24. Each of the half-shaped outer rings 3 in which possible fitting grooves 32 are formed is formed with high strength by cold forging, and then the outer ring 3 is placed on the outer periphery of the connecting boss portion 22 of the inner ring 2. Holes 21 ... 21, 31 ... 31 face each other In this state, the fitting groove 32 is fitted into the fitting portion 24 so that the fitting groove 32 is non-rotatably fitted, and thereafter, the distal end portion of the connecting boss portion 22 penetrating the outer ring 3 and projecting outward is provided on the outer ring 3. The two rings 2 and 3 are integrally joined together while maintaining high strength by cold forging.

In the invention according to claim 3 of the present application, as a two-member caulking method, first, a connecting boss portion 22 protruding in the axial direction is continuously provided on the inner diameter portion of the ring-shaped main body 20, and the outer peripheral surface of the connecting boss portion 22 The one member 2 having the fitting portion 24 formed therein and the other member 3 in which the fitting groove 32 that can be fitted to the fitting portion is formed in the inner diameter portion of the ring-shaped main body 30 are respectively high by cold forging. Next, the second member 3 is fitted to the outer periphery of the connecting boss portion 22 of the one member 2 so that the fitting portion 24 and the fitting groove 32 are fitted to each other so as not to rotate. The connecting boss portion 22 that penetrates the member 3 and protrudes outward is caulked along the outer surface of the outer ring 3 so that both members 2 and 3 are maintained while maintaining high strength by cold forging. It is characterized by being integrally coupled.

According to the pretension ring of the present invention, the inner ring 2 and the outer ring 3 formed with high strength by cold forging such as a press are integrally joined by caulking to maintain the high strength while maintaining the high strength. Therefore, the conventional half-ring with a symmetrical shape is softened by welding heat unlike the case where it is integrally joined by welding at the butt surface, and the strength is not lowered. A high quality pretension ring can be obtained. As a result, it is not necessary to perform post-caulking carburizing and quenching, and a high-strength and high-precision pretension ring can be provided at low cost.
In addition, the inner ring 2 and the outer ring 3 are integrated by caulking while being positioned so as not to rotate, for example, by serration fitting. In this state, both rings 2 and 3 can be securely and securely joined.

Further, according to the method of manufacturing a pretension ring of the present invention, first, the inner ring 2 and the outer ring 3 are formed with high strength by cold forging such as a press, and then both the rings 2 and 3 are integrated by caulking. Since the pretension ring 1 is formed while maintaining high strength by being bonded to the steel, as described above, the strength is not reduced by softening due to welding heat, and high strength and high quality. A pretension ring can be manufactured. As a result, it is not necessary to perform post-caulking carburizing and quenching, and a high-strength and high-precision pretension ring can be provided at low cost.
In addition, the inner ring 2 and the outer ring 3 are integrated by caulking while being positioned so as not to rotate, for example, by serration fitting. In this state, both rings 2 and 3 can be securely and securely joined.

  Furthermore, as a two-member caulking method, first, the one member 2 integrally connected with the caulking portion 22 and the other member 3 coupled thereto are formed with high strength by cold forging such as a press, respectively. If the above-described crimping portion 22 is crimped to the other member 3 in a state in which both the members 2 and 3 are brought into contact with each other, the two members 2 and 3 are integrally coupled while maintaining high strength. To obtain a high-quality joint member that maintains the high strength during cold forging without being softened by welding heat and being reduced in strength as in the case where the two members are joined together by welding at the butting surfaces. Can do. As a result, it is not necessary to perform post-caulking carburizing and quenching, and a high-strength and high-accuracy coupling member can be provided at low cost. Therefore, according to the two-member caulking method, it is not limited to the pre-tension ring, and can be widely used for, for example, a combination of a split type multi-stage sprocket, a split type multi-stage gear, or a split type block member. it can.

It is a longitudinal cross-sectional view of the pretension ring which concerns on this invention. It is a front view of the pretension ring. It is the left side view. It is the same right view. It is the same longitudinal cross-sectional view. It is shape explanatory drawing after forging of an inner ring. It is shape explanatory drawing after formation of a pilot hole of an inner ring. It is shape explanatory drawing after the serration groove | channel formation of an inner ring. It is shape explanatory drawing after the outer shape extraction of an inner ring. It is shape explanatory drawing after forging of an outer ring. It is shape explanatory drawing after the serration groove | channel formation of an outer ring. It is shape explanatory drawing after the outer shape extraction of an outer ring. It is shape explanatory drawing after the primary crimping of a pretension ring. It is shape explanatory drawing after the last crimping of a pretension ring. It is explanatory drawing of a prior art example. It is an exploded view of the pre-tension ring before the welding.

  Hereinafter, the pretension ring according to the present invention will be described with reference to the drawings.

  1 and 5 show a pretension ring according to the present invention, and the pretension ring 1 includes a half-shaped inner ring 2 and a half-shaped outer ring 3. Both the inner ring 2 and the outer ring 3 are formed by forging a forged material having a predetermined shape with a cold forging machine such as a press to form a high strength (strongly processed and hardened). As shown in FIG. 1 and FIG. 2, a plurality of half-split holes 21... A boss portion 22 is formed, a serration groove 23 is formed over the entire inner peripheral surface of the connecting boss portion 22, and a serration 24 is formed from the intermediate portion to the tip portion of the protruding outer peripheral surface of the connecting boss portion 22. Further, the outer ring 3 has a large number of ball half-receiving holes 31... 31 formed in the outer diameter portion of the ring-shaped main body 30 in the circumferential direction, and serration grooves 32 are formed through the inner diameter portion. In the present embodiment, the serration grooves 23, the serrations 24, the serration grooves 32, and the like are formed by press working with a press without lowering the high strength due to the forging after cold forging.

  As described above, the outer ring 3 is provided on the outer periphery of the connecting boss portion 22 of the inner ring 2 formed with high strength by cold forging, and the half receiving holes 21... 21, 31. The serration groove 32 is fitted into the serration 24 in a state of being opposed to each other so that the serration groove 32 cannot be rotated, and the distal end portion of the connecting boss portion 22 protruding outward from the inner diameter portion of the outer ring 3 is attached to the outer ring 3. The two rings 2 and 3 are integrally joined by caulking along the outer side surface, and the pretension ring 1 is formed while maintaining high strength by cold forging.

  In the embodiment shown in the figure, a polygonal central recess 25 is formed at the central portion of the outer surface of the ring-shaped main body 20 in the inner ring 2 to ensure rigidity while reducing the weight, and the outer ring 3. A polygonal central recess 33 is also formed at the central portion of the outer side surface in order to ensure rigidity while reducing the weight. And the crimping end 22a of the connection boss | hub part 22 by which crimping was carried out is made to be settled in the center recess 33, without protruding outside. Further, the positioning of the outer ring 3 with respect to the inner ring 2 at the time of the fitting, that is, the interval is set by setting the length of the serration 24 formed from the front end portion to the intermediate portion of the connecting boss portion 22.

  As described above, the inner ring 2 and the outer ring 3 formed with high strength by cold forging are integrally joined by caulking to form the pretension ring 1 while maintaining high strength. A conventional halved ring with a symmetrical shape is not softened by welding heat and does not decrease in strength like the one that is integrally joined by welding at the butt surface, and a high strength and high quality pretension ring is obtained. be able to. As a result, it is not necessary to perform post-caulking carburizing and quenching, and a high-strength and high-precision pretension ring can be provided at low cost.

  Further, since the inner ring 2 and the outer ring 3 are integrated by caulking while being positioned by serration fitting, both the inner ring 2 and the outer ring 3 are positioned under the condition that the half-receiving holes 21 and 31 of the ball are accurately aligned. The rings 2 and 3 can be securely and securely joined.

  Furthermore, since the polygonal center recesses 25 and 33 are formed in the center part of the outer surface of both the rings 2 and 3 so as to coincide with the half receiving holes 21 and 31, respectively, The recesses 25 and 33 can effectively reduce the weight while ensuring sufficient rigidity of the ball receiving holes 21 and 31.

  Next, a method for manufacturing a pretension ring according to the present invention will be described with reference to the drawings.

  When forming one inner ring 2 in the pretension ring 1, first, as shown in FIGS. 6 (a), (b), (c), (d), a forging material having a predetermined shape is cold forged. A number of ball half-receiving holes 21... 21 are formed in the circumferential direction in the outer diameter portion of the disk-shaped main body 20A (11 in the figure), and from the center of the inner surface of the disk-shaped main body 20A. A bottomed cylindrical connecting boss portion 22 protruding in a cantilever shape inward in the axial direction is continuously provided, and a serration groove 23 is formed on the inner peripheral surface of the connecting boss portion 22 and a serration 24 is formed on the outer peripheral surface. Furthermore, a first molded body 2A is formed in which a central recess 25 having a polygonal outer periphery is formed at the center of the outer surface so as to coincide with the formation positions of the half-receiving holes 21.

  Next, as shown in FIGS. 7A, 7 </ b> B, and 7 </ b> C, the center portion of the disk-shaped main body 20 </ b> A in the first molded body 2 </ b> A is punched into a circular shape by pressing with a press machine, and the pilot hole 26. The first molded body 2A having the ring-shaped main body 20 with a clear prepared hole 26 is formed.

  After that, as shown in FIGS. 8A, 8B, and 8C, in the pilot hole 26 portion of the ring-shaped main body 20 in the first molded body 2A by the press working by the press machine, Serrations are removed so as to coincide with the serration grooves 23 on the peripheral surface, and serration grooves 23 extending through the entire inner surface of the ring-shaped main body 20 from the connection boss portion 22 are formed to penetrate therethrough.

  Thereafter, as shown in (a), (b), (c), and (d) of FIG. 9, the outer periphery of the ring-shaped main body 20 in the first molded body 2A is trimmed (trimmed) by pressing with a press. The inner ring 2 that is in a completed state before crimping is formed.

  When forming the other outer ring 2 in the pretension ring 1, first, as shown in FIGS. 10 (a), (b), (c), (d), a forged material having a predetermined shape is cold-worked. Forged by a forging machine, a large number (11 in the figure) of half-slotted holes 31 for balls are formed in the outer diameter portion of the disk-shaped main body 30A in the circumferential direction, and the center of the inner surface of the disk-shaped main body 30A. The bottomed cylindrical portion 30a protruding in a cantilever shape inward in the axial direction from the portion is continuously provided, and at the center portion of the outer surface of the disc-shaped main body 30A, the half-receiving holes 31 ... 31 are formed. A second molded body 3A is formed in which a central recess 33 having a polygonal shape (11-angle shape in the figure) is formed so as to match.

  Next, as shown in (a), (b), (c), and (d) of FIG. 11, the center portion of the disc-shaped main body 30 </ b> A in the second molded body 3 </ b> A is pressed against the inner by the press working by a press machine. Serrations are removed by matching with the serrations 24 on the outer peripheral surface of the connecting boss portion 22 of the ring 2, and a serration groove 32 is formed through the center of the ring-shaped main body 30. As the serration groove 32 is punched, the bottomed cylindrical portion 30a is simultaneously punched.

  Thereafter, as shown in FIGS. 12A, 12B, 12D, and 12D, the outer periphery of the ring body 30 is extracted (trimmed) by press working with a press machine, and completed before crimping. The outer ring 3 to be in a state is formed.

  And the inner ring 2 and the outer ring 3 formed by cold forging and press working in this way are integrally joined by caulking.

  In this case, as shown in FIGS. 13 (a), (b), (c), and (d), the outer ring 3 is connected to the connecting boss portion 22 of the inner ring 2, and the half receiving holes of both the rings 2 and 3 are used. 21, 21, 31, 31 are opposed to each other with the serration 24 and the serration groove 34, and the center of the outer ring 3 is pressed by a primary caulking press machine in the fitted state. A primary caulking process is performed so that the distal end portion of the connecting boss portion 22 projecting outward from the recess is expanded by about 45 degrees radially outward. As a result, as shown in FIG. 13C, both the rings 2 and 3 are integrally crimped together by caulking.

  After that, as shown in FIGS. 14A and 14B, the pre-tensioning ring that has been primary caulked and joined is further pushed by the press machine for secondary caulking, and the tip end portion of the connecting boss part 22 that has been caulked primary and caulked further. The diameter is increased by about 90 degrees, and final crimping is performed so that the tip crimping portion 22a is in close contact with the outer surface of the central recess 33 of the outer ring 3 with a large joint surface. As a result, both rings 2 and 3 can be integrally crimped while maintaining high strength by cold forging.

  Then, the pretension ring 1 as a product can be obtained by performing a plating process as a post process.

  As described above, the inner ring 2 and the outer ring 3 are formed with high strength by cold forging, and then both the rings 2 and 3 are joined together by caulking and the pretension ring 1 is maintained while maintaining high strength. Since it is formed, the high-strength and high-quality pre-tension ring 1 can be manufactured at a low cost without special carburizing and quenching.

  Further, since the inner ring 2 and the outer ring 3 are integrated by caulking, for example, in a state where they are non-rotatably positioned by serration fitting or the like, the half receiving holes 21 and 31 of the balls are accurately aligned with each other. Both rings 2 and 3 can be securely and securely joined under the condition.

  Moreover, as a fitting part and a fitting groove, it is not limited to a serration and a serration groove at all like the above-mentioned embodiment, Splines and other fitting structures may be sufficient.

  Further, the two-member caulking method of the present invention, that is, firstly the one member 2 in which the caulking portion 22 is integrally connected and the other member 3 coupled thereto are formed with high strength by cold forging, respectively, In the caulking method in which both the members 2 and 3 are joined to each other while maintaining the high strength by caulking the caulking portion 22 to the other member 3 in a state where both the members 2 and 3 are abutted, The present invention is not limited to the pre-tension ring, and can be widely used, for example, for joining a split type multistage sprocket, a split type multistage gear, or a split type block member.

DESCRIPTION OF SYMBOLS 1 Pretension ring 2 Inner ring 3 Outer ring 20 Ring-shaped main body 21 Half split receiving hole 22 Connecting boss part 23 Serration groove 24 Serration 25 Central recess 30 Ring-shaped main body 31 Half split receiving hole 32 Serration groove 33 Central recess

Claims (3)

  A large number of ball half-receiving holes 21... 21 are formed in the circumferential direction in the outer diameter portion of the ring-shaped main body 20, and a connecting boss portion 22 protruding in the axial direction is connected to the inner diameter portion. A half-shaped inner ring 2 in which a fitting groove 23 is formed on the inner peripheral surface of the boss portion 22 and a fitting portion 24 is formed on the outer peripheral surface thereof. A plurality of holes 31... 31 are formed in the circumferential direction, and an inner ring portion is provided with a half-shaped outer ring 3 in which a fitting groove 32 that can be fitted into the fitting portion is formed. While the rings 2 and 3 are each formed with high strength by cold forging, the outer ring 3 is formed on the outer periphery of the connecting boss portion 22 of the inner ring 2 with both half-receiving holes 21... 21, 31. Rotating by fitting the fitting groove 32 into the fitting portion 24 The two ends of the ring 2 are squeezed so that the tip of the connecting boss part 22 that penetrates the outer ring 3 and the outer surface of the outer ring 3 is maintained along the outer surface of the outer ring 3 while maintaining high strength by cold forging. , 3 are integrally connected to each other.   First, a large number of ball half-receiving holes 21... 21 are formed in the circumferential direction in the outer diameter portion of the ring-shaped main body 20, and a connecting boss portion 22 projecting in the axial direction is connected to the inner diameter portion. The inner peripheral surface of the connecting boss portion 22 has a fitting groove 23 and the outer peripheral surface has a fitting portion 24 formed at the front end thereof. A plurality of half-splitting holes 31... 31 for the ball are formed in the circumferential direction, and a half-shaped outer ring 3 in which a fitting groove 32 that can be fitted to the fitting part 24 is formed on the inner diameter part. Each is formed with high strength by cold forging, and then the outer ring 3 is placed on the outer periphery of the connecting boss portion 22 of the inner ring 2 with the half-receiving holes 21... 21, 31. The fitting groove 32 is fitted into 24 and fitted so as not to rotate. Thereafter, the front end portion of the connecting boss portion 22 that penetrates the outer ring 3 and protrudes outward is caulked so as to be along the outer surface of the outer ring 3, and both rings 2 are maintained while maintaining high strength by cold forging. , 3 are integrally connected to each other.   First, one member 2 in which a connecting boss portion 22 protruding in the axial direction is connected to an inner diameter portion of the ring-shaped main body 20 and a fitting portion 24 is formed on the outer peripheral surface of the connecting boss portion 22, and the ring-shaped main body. The other member 3 in which the fitting groove 32 that can be fitted to the fitting portion is formed in the inner diameter portion of the member 30 with high strength by cold forging, and then on the outer periphery of the connecting boss portion 22 of the one member 2 The second member 3 is fitted into the fitting portion 24 and the fitting groove 32 so as not to rotate, and then the tip of the connecting boss portion 22 that protrudes outward through the second member 3. Two-member crimping, characterized in that the parts are crimped along the outer surface of the outer ring 3 and the members 2 and 3 are joined together while maintaining high strength by cold forging. Construction method.

Images