TW201836733A - A rivet fastening device - Google Patents

Abstract

Provided is a rivet fastening device capable of easily fastening a blind rivet which has a short mandrel and which does not require the machining of the mandrel after the rivet body and the mandrel are mounted together. The mandrel (25) of a blind rivet (20) comprises a mandrel head (27) and a mandrel shaft section (26). The mandrel shaft section has a circular column section (26c), a thin shaft section (28), and a rear end section which has the same outer diameter as the circular column section. The pull-in section of a rivet fastening device (1), which grips the mandrel shaft section, has: a pulling head (36); a jaw case (32) having an inner peripheral surface (31) having a forwardly decreasing inner diameter; and a jaw (40) disposed in the jaw case and having an outer peripheral surface in contact with the inner peripheral surface of the jaw case. The tilt angle ([alpha]j) of the outer peripheral surface of the jaw is smaller than the tilt angle ([alpha]c) of the inner peripheral surface of the jaw case. The grooves (45) between the two segments of the jaw are narrow at the front outer periphery of the jaw and is wide at the rear outer periphery of the jaw. The front part of the axial hole of the jaw is a small-diameter hole (46s), and the rear part thereof is a large-diameter hole (46b).

Description

Rivet fastening device

The present invention relates to a rivet fastening device, and more particularly to a rivet fastening device for fastening a blind rivet having a short mandrel.

The blind rivet comprises a rivet body and a mandrel. The rivet body includes a cylindrical sleeve and a flange of a large diameter formed at one end of the sleeve. The mandrel includes an elongated mandrel shaft portion and a mandrel head formed at one end of the mandrel shaft portion and having a larger diameter than the inner diameter of the sleeve. The mandrel shaft portion is inserted from one end of the sleeve of the rivet body. The rivet body and the mandrel are combined in such a manner that the mandrel head abuts against one end of the sleeve and the mandrel shaft portion projects long from the flange. The blind rivet is held by the rivet fastening means in such a manner that the gripped portion of the mandrel shaft portion is inserted into the head of the rivet fastening device and the flange of the rivet body abuts against the head. In the case of a blind rivet held by a rivet fastening device, the sleeve of the rivet body is inserted into the mounting hole of the member to be fastened so that the flange faces the fastened member. Then, the mandrel shaft portion is forcibly pulled by the action of the pull-in portion of the rivet fastening device, and the mandrel head portion enlarges one portion of the sleeve and is strongly clamped between the enlarged sleeve and the flange Fastening member. The mandrel is broken at a breakable portion formed in a small diameter of the mandrel shaft portion. Even if the fastening member is a panel having a large area such as a vehicle body panel, the blind rivet has the advantage of being able to perform fastening work from one side. In general, blind rivets are made of metal such as steel or aluminum. When the previous blind rivet is tightened, the rivet fastening device grips the grip portion of the spindle shaft portion with the jaw clamp and pulls it strongly. Thus, the blind rivet has a mandrel shaft portion that is elongated in the axial direction, and the grip portion of the mandrel shaft portion is formed with a groove to prevent slipping. The jaw of the rivet fastening device applies a high surface pressure to the spindle shaft portion, and mainly uses the friction force to pull the spindle shaft portion. Therefore, the spindle shaft portion has a long grip portion, and the rivet fastening device also has a long head. unit. There is a blind rivet in which a large diameter portion having a large outer diameter is formed at an end portion of the mandrel opposite to the mandrel head in order to shorten the mandrel. Such blind rivets are referred to as double-ended rivets. When the double-headed rivet is tightened, the large diameter portion of the mandrel is pulled, so that the grip portion of the mandrel shaft portion can be prevented from disintegrating due to a large frictional force. However, in the case of a double-headed rivet, since the outer diameter of the large diameter portion of the front end of the mandrel is larger than the outer diameter of the sleeve, after assembling the rivet body and the mandrel, the front end of the mandrel must be processed to form Large diameter department. Further, the large diameter portion having an outer diameter larger than the outer diameter of the sleeve passes through the opening portion of the head member of the rivet fastening means, and therefore, the head member supporting the flange of the rivet body must be divided into a plurality of separate head members. Therefore, there are defects in cost increase. Patent Document 1 discloses a rivet mounting device for fastening such a double-headed rivet. The mandrel of the double-ended rivet has a mounting head that is engaged with the end surface of the tubular rivet body, and a pull tab for pulling the mandrel. The rivet mounting device has a pull tab assembly that engages with a pull tab of the spindle, and a support portion that supports the rivet. The pulling section pulls the back of the core axially and fastens the double-headed rivet. The mandrel of the double-headed rivet used in Patent Document 1 has a pull tab for pulling the mandrel. The outer diameter of the puller of the mandrel is larger than the outer diameter of the rivet. Thus, after assembling the rivet and the mandrel, the step of expanding the mandrel to form the pull tab is required. The rivet mounting device has a plurality of support sections that surround the pull tab assembly that are used to support the rivet flange when the rivet is tightened. The support section needs to be divided into sections so that the large diameter of the mandrel is passed. The pulling assembly system that engages with the pulling head of the mandrel pulls the edge to the pulling head, so that if the diameter of the pulling head is small, the pulling head cannot be stuck to the edge and is ground and slipped. Therefore, there is a possibility that the mandrel cannot be pulled in. Patent Document 2 discloses a blind rivet having a rivet body including a flange and a hollow sleeve, and a mandrel (rivet pin) having a mandrel head disposed at an end portion of the spindle shaft portion. The mandrel has a distal end portion having an outer diameter corresponding to the outer diameter of the mandrel, a conical portion which is tapered from the distal end portion toward the mandrel head portion, and a cylindrical portion having a fixed thickness. In the installation work of the blind rivet, the jaw clamp (fastening chuck) of the rivet fastening device is engaged with the conical portion of the blind rivet. The jaws are adapted to the conical portion of the blind rivet. Moreover, the side of the jaw and the end of the mandrel have interlocking edges. The force for tightening the blind rivet is transmitted from the jaw to the mandrel via the conical portion. Moreover, the interlocking edge is engaged with the end portion to improve the transmission of the pulling force. Therefore, the wear of the jaw and the material wear of the mandrel are reduced. The outer diameter of the end portion of the mandrel of the blind rivet of Patent Document 2 corresponds to the outer diameter of the mandrel, and thus can pass through the sleeve. Thus, after the rivet body is assembled with the mandrel, subsequent machining of the mandrel is not required. Moreover, since the head piece of the rivet fastening device can be passed through, it is not necessary to divide the head piece into a plurality of sections in the circumferential direction. However, the mandrel of the blind rivet of Patent Document 2 has a distal end portion having a large diameter, a conical portion having a tapered tapered shape, a cylindrical portion having a fixed thickness, and a mandrel head having a complicated shape. It takes a lot of work to process the conical cone. Since a plurality of mandrels are used, the shape becomes complicated and the cost is increased. Moreover, when the fastening pressure of the mandrel is insufficient, the interlocking edge will engage with the end portion of the mandrel to improve the transmission of force. However, the interlocking edges are auxiliary. It is considered that the inclination angle of the peripheral surface other than the sharp jaw is the same as the inclination angle of the inner circumference of the jaw sleeve. Therefore, there is a possibility that the force of tightening the mandrel from the jaw sleeve to the jaw clip cannot be effectively transmitted. Therefore, blind rivets that can be easily machined without the need for mandrel processing after assembly of the rivet body and the mandrel are sought. Moreover, a rivet fastening device capable of easily fastening such a blind rivet is sought. [PRIOR ART DOCUMENT] [Patent Document 1] Japanese Patent Laid-Open No. Hei 8-318344 (Patent Document 2) Japanese Patent Laid-Open No. Hei 5-87112

[Problem to be Solved by the Invention] An object of the present invention is to provide a blind rivet having a short mandrel, a rivet body and a mandrel assembled without a mandrel, and a rivet capable of easily fastening such a blind rivet. Fastening device. [Technical Solution to Problem] A first aspect of the present invention is a rivet fastening device characterized in that a blind rivet including a mandrel and a rivet body is fastened to a member to be mounted, and has a pull-in portion that grips Pulling in the shaft shaft portion of the mandrel; and a head cover for supporting the flange of the rivet body; the pull-in portion having: a pulling head that moves in the axial direction; And the inner peripheral surface having an inner diameter that decreases toward the front end; and an jaw clamp disposed in the outer jaw and having abutting against the outer jaw The outer circumferential surface of the inner circumferential surface; the inclination angle of the outer circumferential surface of the jaw is smaller than the inclination angle of the inner circumferential surface of the jaw jacket. If the inclination angle of the peripheral surface of the jaw is smaller than the inclination angle of the inner circumference of the jaw sleeve, the inner peripheral surface of the jaw jacket pushes the force of the outer surface of the jaw to be larger than the rear. Therefore, the spindle shaft portion is gripped more strongly than the rear end portion at the thin shaft portion. Preferably, the e-clip includes two e-clip sections, and the slot between the two e-clip sections is a narrow narrow groove in the outer periphery of the thick part after the truncated cune, and is thicker than the above The outer peripheral portion is a wide groove wider than the narrow groove, and the narrow groove and the wide groove form a grooved step. If the width of the groove at the periphery of the front of the jaw is wide, the two sections of the jaw may be close to each other in front. Therefore, the mandrel is more strongly gripped at the thin shaft portion, and is pulled by a relatively high frictional force with a high surface pressure. Preferably, the jaw clip has a shaft hole for gripping the spindle shaft portion, the shaft hole is a small diameter hole having a small inner diameter, and the rear is a large diameter hole having a large inner diameter, and the small diameter is The hole and the large diameter hole become a shaft hole step. If the jaw clamp has a shaft hole for gripping the shaft shaft portion, and the shaft core hole has a small diameter hole with a small inner diameter, the rear is a large diameter hole with a large inner diameter, and between the small diameter hole and the large diameter hole When the shaft hole step is formed, the thin shaft portion of the mandrel is disposed inside the small diameter hole of the jaw, and the rear end portion of the mandrel is disposed inside the large diameter hole of the jaw, and the shaft hole step can pull the core The step difference between the thin shaft portion and the rear end portion of the shaft. Preferably, the mandrel of the blind rivet fastened by the rivet fastening device includes a mandrel head at one end and the mandrel shaft portion extending from the mandrel head, the mandrel shaft portion having a cylindrical portion, an outer diameter of the rear portion of the cylindrical portion, a thinner shaft portion thinner than the cylindrical portion, and an outer diameter of the rear portion of the thin shaft portion, which are the same as the cylindrical portion, and the thin shaft portion and the rear end portion When the pull-in portion is located at the front position, and the blind rivet is provided in the rivet fastening device, the thin shaft portion of the mandrel is disposed inside the small-diameter hole of the jaw, and the mandrel The rear end portion is disposed inside the large diameter hole of the jaw. If the mandrel shaft portion has a cylindrical portion, the outer diameter of the cylindrical portion is smaller than the cylindrical portion, and the outer diameter of the rear portion of the thin shaft portion is the same as the cylindrical portion, the outer diameter of the rear end portion It is the same as the cylindrical portion, so that when the rivet body is assembled with the mandrel, it is not necessary to machine the rear end portion. When the thin shaft portion of the mandrel is placed inside the small diameter hole of the jaw and the rear end of the mandrel is placed inside the large diameter hole of the jaw, the size of the jaw and the size of the spindle shaft are adapted. In combination, the small diameter hole of the jaw can apply a pulling force to the thin shaft of the mandrel, and the large diameter hole of the jaw can apply a pulling force to the thick shaft of the mandrel. Preferably, when the drawing portion is retracted, the axial hole step between the small diameter hole and the large diameter hole pulls the step between the thin shaft portion and the rear end portion. When the jaw pulls the mandrel, the step of the jaw is abutted on the step of the mandrel, so that the pulling force is easily applied, compared with when a high surface pressure is applied and the mandrel is pulled only by friction. The mandrel is not easily plastically deformed. According to a second aspect of the present invention, a jaw is characterized in that the jaw of the rivet fastening device for fastening the member to be mounted is provided by a blind rivet including a mandrel and a rivet body, and the jaw includes two jaw segments. The groove between the two jaw segments is a narrow narrow groove after the truncated jaw, and the tapered portion at the front is a wide wide groove, and the narrow groove and the wide groove become Slotted step. Preferably, the jaw clip has a shaft hole for gripping the spindle shaft portion of the spindle, the shaft hole is a small diameter hole having a small inner diameter, and the rear is a large diameter hole having a large inner diameter. The small diameter hole and the large diameter hole become a shaft hole step. A third aspect of the present invention is a pull-in portion, which is characterized in that a blind rivet including a mandrel and a rivet body is fastened to a rivet fastening device of a member to be attached, and is pulled into a spindle shaft portion of the spindle. The pull-in portion has: a pulling head that moves in the axial direction; a jaw sleeve that is disposed integrally with the pulling head adjacent to the pulling head, and has an inner circumferential surface whose inner diameter becomes smaller toward the front end; And an jaw clip disposed in the outer jaw sleeve and having a peripheral surface abutting the inner peripheral surface of the jaw jacket; the outer peripheral surface of the jaw clip having an inclination angle smaller than the inner circumference of the jaw jacket The angle of inclination of the face. [Effects of the Invention] According to the present invention, it is possible to provide a blind rivet which has a short mandrel, is assembled without a mandrel after assembling the rivet body and the mandrel, and can provide a rivet which can easily fasten such a blind rivet. Device.

Hereinafter, the blind blind rivet 1 and the prior rivet fastening device 10 will be described. Next, the blind rivet 20 and the rivet fastening device 30 according to an embodiment of the present invention will be described with reference to the drawings. (Previous Blind Rivet) FIG. 1 is a cross-sectional view of a prior rivet fastening device 10 that holds a previous blind rivet 1. The blind rivet 1 comprises a rivet body 2 and a mandrel 5. The rivet body 2 comprises a cylindrical sleeve 3 and a flange 4 formed at one end of the sleeve 3 and having a larger diameter than the sleeve 3. The mandrel 5 includes an elongated cylindrical mandrel shaft portion 6 and a mandrel head portion 7 formed at one end of the mandrel shaft portion 6. A breakable portion is formed in the vicinity of the mandrel head 7 of the mandrel shaft portion 6. A grip portion 8 having a circumferential groove is formed in the mandrel shaft portion 6 for gripping the jaw of the rivet fastening device 10. The rivet body 2 is combined with the mandrel 5, and the mandrel head 7 abuts against one end of the sleeve 3, and the mandrel shaft portion 6 projects long from the flange 4. (Previous Rivet Fastening Device) Referring to Fig. 1, the prior rivet fastening device 10 will be described. The head portion in front of the rivet fastening device 10 has a head member 11 at the front end and a cylindrical head cover 13 extending rearward from the head member 11. The outer end portion of the head piece 11 has a large outer diameter, and the front end portion is disposed to abut against the opening of the head cover 13. The head piece 11 is formed with a central hole in the axial direction. The mandrel shaft portion 6 of the mandrel 5 is received in the center hole. The flange 4 of the rivet body 2 abuts against the end face of the head piece 11. The pin 11P is configured to slightly enter the center hole of the head piece 11. An O-ring 11R is disposed around the head piece 11. The pin 11P is pressed by the O-ring 11R, and the front end of the pin 11P protrudes toward the center hole of the head member 11, and one of the center holes is narrowed. An armpit 12 is disposed at a front end portion of the inner side of the head cover 13. The jaw jacket 12 is substantially cylindrical and slidable within the head cover 13. The inner diameter of the front end side of the inner side of the jaw sleeve 12 gradually becomes smaller, and the jaw clip 14 is received inside the jaw sleeve 12. The jaws 14 are formed in a pointed shape toward the head piece 11. The jaws 14 are divided into two to three in the circumferential direction, and are combined to form a hollow cylindrical body of the axial cavity, and are housed in a narrow-shaped cavity of the cylindrical jaw jacket 12. The jaw 54 receives the spindle shaft portion 6 of the blind rivet 1 and grips the grip portion 8. The rearward inclination angle of the outer peripheral surface of the jaw 54 is the same as the rearward inclination angle of the inner circumferential surface 31 of the jaw cover 12. The outer peripheral surface of the jaw 54 is tightly fitted to the inner peripheral surface 31 of the jaw cover 12. A substantially cylindrical pull head 16 and a jaw lock 17 located outside the pull head 16 are disposed on the inner side of the head cover 13 and on the rear side of the jaw cover 12. On the inner side of the pulling head 16 and behind the jaws 14, a jaw-shaped pusher 15 having a hollow cylindrical body is disposed. Between the jaw clamp 15 and the pulling head 16, an jaw thruster spring 18 is disposed, and the jaw thruster 15 is pushed forward. The pulling head 16 is fixed to the ball screw 19 at the rear thereof. The ball screw 19 is a cylindrical member and extends in the axial direction. The jaw cover 12, the pulling head 16, the jaw holder 17 and the ball screw 19 are disposed in a state in which the axis is aligned with respect to the head cover 13, and are axially slidably disposed. The members are integrally reciprocable in the axial direction, and the jaws 14 are pulled back to the head cover 13 and returned to the front of the head cover 13. The axial portion of each of the jaw 14, the jaw clutch 15, the pulling head 16, and the ball screw 19 is formed as a continuous hollow passage from the inlet of the head to the inlet of the recovery container. The spindle shaft portion 6 is inserted into the axial portion of the jaws 14. The broken mandrel shaft portion 6 is fed into the recovery container through the hollow passage. When the mandrel 5 of the blind rivet 1 is located in the axial hole of the jaw 14 , if the jaw 12 is pulled backward, the mandrel shaft portion 6 of the blind rivet 1 held in the axial hole of the jaw 14 can be Strongly grasped. When the main shaft (not shown) of the rivet fastening device 10 rotates, the ball screw 19 linearly moves rearward. The pulling head 16, the jaw gripping member 17, and the jaw sleeve 12 are integrally moved rearward (the right direction of Fig. 1). The jaws 14 exert a central axial force on the slope of the tapered portion. The mandrel shaft portion 6 of the blind rivet 1 is gripped by the jaws 14 and is strongly pulled rearward. The mandrel 5 is broken at the fracture portion, and the blind rivet 1 is fastened. (Blind Rivet of the Embodiment of the Present Invention) Next, the blind rivet 20 according to the embodiment of the present invention will be described with reference to Figs. 2 to 4 . Figure 2 is a front elevational view of a blind rivet 20 in accordance with an embodiment of the present invention. 3 is a front elevational view of the rivet body 22 of the blind rivet 20. 4 is a front elevational view of the mandrel 25 of the blind rivet 20. The blind rivet 20 of the embodiment of the present invention includes a rivet body 22 and a mandrel 25. As shown in FIG. 3, the rivet body 22 includes a cylindrical sleeve 23 and a flange 24 formed at one end of the sleeve 23 and having a larger diameter than the sleeve 23. A through hole is formed from the end of the sleeve 23 to the flange 24. As shown in FIG. 4, the mandrel 25 has an elongated cylindrical mandrel shaft portion 26 and a mandrel head portion 27 formed at one end of the mandrel shaft portion 26. The outer diameter of the mandrel head 27 is larger than the inner diameter of the sleeve 23 and is substantially equal to the outer diameter of the sleeve 23. A breakable portion 26h is formed in the vicinity of the mandrel head portion 27 of the mandrel shaft portion 26. The mandrel shaft portion 26 is formed with a cylindrical portion 26c and a cylindrical thin shaft portion 28 whose outer diameter on the rear end side of the cylindrical portion 26c is slightly thinner than the cylindrical portion 26c. The rear end side of the thin shaft portion 28 is a cylindrical rear end portion 29 having an outer diameter substantially the same as that of the cylindrical portion 26c. A step 28d is formed between the thin shaft portion 28 and the rear end portion 29. In one embodiment, the diameter of the cylindrical portion 26c is fc = 3.65 mm, the diameter of the thin shaft portion 28 is fn = 3.44 mm, and the diameter of the rear end portion 29 is fe = 3.64 mm. The step 28d between the thin shaft portion 28 and the rear end portion 29 is 0.1 mm on one side. As shown in FIG. 2, the rivet body 22 is combined with the mandrel 25, and the mandrel head 27 abuts against one end of the sleeve 23, and the mandrel shaft portion 26 projects from the flange 24 in a long shape. The outer diameter of the rear end portion 29 is substantially equal to the outer diameter of the mandrel shaft portion 26, and is equal to or slightly smaller than the inner diameter of the sleeve 23. The mandrel shaft portion 26 and the rear end portion 29 can pass through the through hole of the sleeve 23. Therefore, after the rivet body 22 is assembled with the mandrel 25, the mandrel 25 need not be processed. Referring to FIG. 5, the mandrel shaft portion 26 of the blind rivet 20 is inserted into the center hole of the head cover 33 of the rivet fastening device 30. The flange 24 of the rivet body 22 abuts against the end surface of the head cover 33. The rivet body 22 and the mandrel head 27 are exposed from the head cover 33. The thin shaft portion 28 and the rear end portion 29 of the mandrel 25 are gripped by the jaws 40. In Fig. 5, the jaw sleeve 32 and the jaw clip 40 are located at the front position. At the front position, the mandrel shaft portion 26 is inserted into the shaft hole of the jaw 40 for gripping. In the present specification, the front direction of the head of the rivet fastening device 30 (the left side in FIG. 5) is referred to as the front side, and the direction behind the head portion is referred to as the rear side. (Rivet Fastening Device According to Embodiment of the Present Invention) A rivet fastening device 30 according to an embodiment of the present invention will be described with reference to Fig. 5 . The rivet fastening device 30 is front to the head cover 33. The head piece does not exist as a separate part, and the front end of the head piece cover 33 functions as a head piece. The rear end portion 29 of the mandrel 25 has substantially the same thickness as the mandrel shaft portion 26, and it can pass through the center hole of the front end portion of the head piece cover 33. Thus, the front end of the head cover 33 does not have to be divided into a plurality of sections. The front end portion of the head cover 33 is formed with a central hole in the axial direction, and the mandrel shaft portion 26 of the mandrel 25 is received in the center hole. An armhole sleeve 32 is disposed at a front end portion of the inner side of the head cover 33. The rear portion of the jaw 32 is substantially cylindrical. The shape of the front end side of the jaw cover 32 corresponds to the shape of the cavity inside the head cover 33 to have a tapered shape. The jaw sleeve 32 is slidable within the head cover 33. The inner shape of the front end side of the jaw sleeve 32 gradually becomes tapered, and the cavity inside the jaw sleeve 32 can accommodate the sharp-shaped jaw 52. The jaw 40 is formed into a tapered shape toward the front end of the head cover 33. The jaw 40 is divided into two in the circumferential direction. After the combination, the shaft portion becomes an axial hole and is received in a narrow-shaped cavity of the cylindrical jaw 32. The jaw 40 is pushed forward in the sharp-shaped jaw jacket 32 by the jaw clamper 35 and the jaw thruster spring 38. The jaw 40 holds the spindle shaft portion 26 of the blind rivet 20 into the shaft hole for gripping. As described below, the jaw 40 and the jaw 32 of the rivet fastening device 30 according to the embodiment of the present invention have a special shape. On the inner side of the head cover 33 and on the rear side of the jaw 32, a substantially cylindrical pull head 36 and a jaw lock 37 located outside the pull head 36 are disposed. On the inner side of the pulling head 36 and behind the jaw 40, a jaw-shaped pusher 35 of a hollow cylindrical body is disposed. An jaw thruster spring 38 is disposed between the jaw clamp 35 and the pulling head 36, and the jaw thruster 35 is pushed forward. The pulling head 36 is fixed to the ball screw 39 at the rear thereof. The ball screw 39 is a cylindrical member and extends in the axial direction. A hollow passage is formed in the axial center of the ball screw 39. The jaw cover 32, the pulling head 36, the jaw holder lock member 37, and the ball screw 39 are disposed in a state in which the shaft center is aligned with respect to the head piece cover 33, and are axially slidably disposed. The members are integrally reciprocable in the axial direction, and the jaws 40 are pulled into the rear position behind the head cover 33, and are returned to the front position in front of the head cover 33. The axial center portion of each of the jaw thruster 35, the pulling head 36, and the ball screw 39 is formed as a continuous hollow passage to the rear recovery container (not shown). The mandrel shaft portion 26 can be inserted into the shaft hole of the jaw 40. The broken mandrel shaft portion 26 is fed into the recovery container through the hollow passage. When the mandrel shaft portion 26 of the blind rivet 20 is located in the axial hole of the jaw 40, if the jaw sleeve 32 is pulled backward, the jaw sleeve 32 applies a central axis to the tapered outer peripheral surface 41 of the jaw 40. To force. Therefore, the spindle shaft portion 26 of the blind rivet 20 held by the axial hole of the jaw 40 is strongly gripped. When the main shaft (not shown) of the rivet fastening device 30 rotates, the ball screw 39 linearly moves rearward. The pulling head 36, the jaw grip locking member 37 and the jaw sleeve 32 are integrally retracted, and the spindle shaft portion 26 of the blind rivet 20 is gripped by the jaw clip 40 and is strongly pulled backward, and the spindle 25 is at the breakable portion. After 26h break, the blind rivet 20 is tightened. When the spindle rotates in the reverse direction, the ball screw 39 linearly moves forward. The ball screw 39, the pulling head 36, the jaw grip 37, and the jaw 32 are integrally advanced and returned to the original position. Here, the jaw 40 and the jaw 32 of the embodiment of the present invention will be described in detail. The jaw 40 can pull the mandrel 25 to a narrower step 28d, and grip the thin shaft portion 28 of the mandrel 25 with a higher surface pressure. When the mandrel 25 is pulled, the thin shaft portion 28 and the rear end portion 29 are not deformed by the surface pressure of the jaw 40 until the breakable portion 26h of the mandrel 25 is broken. (The difference between the inclination angles of the outer circumferential surface of the jaw and the inner circumferential surface of the jaw jacket) Fig. 6 is only a cross-sectional view of the jaw 40 and the jaw sleeve 32 of Fig. 5, and the jaw 40 and the jaw sleeve 32 are located at the front position. Other parts of the rivet fastening device 30 are not shown. The inclination angle αj of the outer circumferential surface 41 of the jaw 40 is smaller than the inclination angle αc of the inner circumferential surface 31 of the jaw 32. The inclination angle αc of the inner circumferential surface 31 of the jaw jacket 32 is equal to the inclination angle αj of the outer circumferential surface 41 of the jaw 52. Here, the inclination angle αc of the inner circumferential surface 31 of the jaw jacket 32 is referred to as the central axis passing through FIG. The angle formed by the line of the two inner peripheral faces 31 of the jaw 32 on the cross section. The inclination angle αj of the outer peripheral surface 41 of the jaw 40 is an angle formed by the line passing through the two outer peripheral faces 41 of the jaw 40 on the section of the central axis of Fig. 6. In the front position, in the sharp portion 42 of the jaw 40, the outer peripheral surface 41 of the jaw 52 is in close contact with the inner peripheral surface 31 of the jaw 32, and in the rear thick portion 43, the outer peripheral surface 41 of the jaw 40 is separated from the outer surface 41. The inner peripheral surface 31 of the jacket 32 is separated by a slight gap. In one embodiment, the inclination angle αc of the inner circumferential surface 31 of the jaw jacket 32 is 20°, and the inclination angle αj of the outer circumferential surface 41 of the jaw 40 is 18°. When the blind rivet 20 is fastened, the outer peripheral surface 41 of the jaw 40 is pulled rearward (to the right of FIG. 6) by the inner peripheral surface 31 of the jaw 32. Since the inclination angle αj of the outer peripheral surface 41 is smaller than the inclination angle αc of the inner peripheral surface 31 of the jaw 32, the inner peripheral surface 31 of the jaw 32 pushes the outer peripheral surface 41 of the jaw 40 The sharp portion 43 on the front side of the thick portion 43 (the left side of FIG. 6) becomes larger. Referring to Figure 5, the jaw 40 and the jaw 32 are located in front of the blind rivet 20 prior to fastening. The mandrel shaft portion 26 of the blind rivet 20 is inserted into the center hole of the head piece cover 33 of the rivet fastening device 30. The flange 24 of the rivet body 22 abuts against the end surface of the head cover 33. Since the thin shaft portion 28 of the mandrel shaft portion 26 is located inside the tapered portion 42 of the jaw 40, the spindle shaft portion 26 is more strongly gripped by the thin shaft portion 28 than the rear end portion 29. The mandrel shaft portion 26 is pulled with a strong frictional force by a high surface pressure. Further, as will be described later, the step 28d of the mandrel shaft portion 26 is strongly pulled by the axial hole step portion 46d of the jaw 40. Fig. 7 is a perspective view of the jaw 40, Fig. 8 is a front view, Fig. 9 is a left side view, and Fig. 10 is a right side view. Figure 11 is a cross-sectional view taken along line A-A of Figure 9. Figure 12 is an enlarged view of a portion C of Figure 8, and Figure 13 is an enlarged view of a portion B of Figure 11. As shown in Fig. 7, the jaw 40 is divided into two upper and lower sections. The outer peripheral surface 41 of the jaw 40 is thinner toward the front end, and the tip end becomes the tapered portion 42. The rear end is the rear thick portion 43. When the jaw 40 is located in the front position shown in FIG. 5, the pointed portion 42 of the jaw 40 is tightly fitted with the jaw 32 in the depth direction of FIG. 5, and is upward and downward in FIG. A groove 45 is formed between them. As shown in FIG. 12, which is an enlarged view of a portion C of FIG. 8 and FIG. 8, the outer portion of the thick portion 43 (the right side of FIG. 8) after the thicker jaw 40 is thicker, and the width of the groove 45 of the jaw 40 is w1. The narrow narrow groove 45n. The groove 45 is a wide groove 45w having a width of w2 on the outer peripheral portion of the rear thick portion 43. The grooved step 45d is formed between the narrow groove 45n and the wide groove 45w. The grooved step portion 45d starts from the rear rough portion 43. That is, the axial length of the narrow groove 45n is shorter than the axial length of the wide groove 45w. The width w1 of the narrow groove 45n<the width w2 of the wide groove 45w is at the position before the jaw 40 and the jaw 32, and the width of the narrow groove 45n is the same from the front end to the groove step 45d, and the wide groove 45w is from the groove step The width from the portion 45d to the rear end portion is the same. In one embodiment, the width w1 = 0.2 mm and the width w2 = 0.5 mm. When the jaw 40 is pulled by the jaw 32, the width of the slot 45 of the tip 42 (left side of FIG. 6) in front of the jaw 40 is large, so that the tip 42 of the two sections of the jaw 40 can be Close to each other. As described above, the inclination angle αj of the outer circumferential surface 41 of the jaw 40 is smaller than the inclination angle αc of the inner circumferential surface 31 of the jaw 32, so that the pointed portions 42 of the jaw 40 are closer to each other. As shown in Fig. 5, the thin shaft portion 28 of the mandrel 25 is located inside the pointed portion 42 of the jaw 52, so that the thin shaft portion 28 is pulled with a strong frictional force by a high surface pressure. (Axis hole step of the clip) As shown in Fig. 13 in the cross-sectional view along line AA of Fig. 9, that is, Fig. 11 and Fig. 11, the clip of the jaw 40 holds the mandrel, so the inner side becomes the shaft. Heart hole. In the vicinity of the sharp portion 42 (the left side of FIG. 11) in front of the jaw 40, the small-diameter hole 46s having a small inner diameter of the shaft hole is near the rear of the jaw 40 and the vicinity of the thick portion 43 (the right side of FIG. 11). The large diameter hole 46b has a large inner diameter. The boundary between the small diameter hole 46s and the large diameter hole 44b becomes the axial core step portion 46d. The inner diameter of the small diameter hole 46s is smaller than the inner diameter of the large diameter hole 46b. The inner diameter of the small diameter hole 46s is fixed from the tapered portion 42 (front end portion) to the axial hole step portion 46d, and the inner diameter of the large diameter hole 44b is from the axial center hole. The step portion 46d to the rear thick portion 43 (rear end portion) is fixed. In one embodiment, the inner diameter of the small diameter hole 46s is 3.2 mm, the inner diameter of the large diameter hole 46b is 3.6 mm, and the side of the axial hole step 46d is 0.2 mm. When the blind rivet 20 is provided in the rivet fastening device 30, the thin shaft portion 28 of the mandrel 25 is disposed inside the small diameter hole 46s of the jaw 40, and the rear end portion 29 of the spindle 25 is disposed in the large diameter hole of the jaw 40 The inside of 46b. The small diameter hole 46s of the jaw 40 abuts against the thin shaft portion 28 of the spindle 25, and the large diameter hole 46b of the jaw 40 abuts against the rear end portion 29 of the spindle 25. When the jaw 40 pulls the mandrel 25, the axis hole portion 46d of the jaw 40 abuts against the step 28d of the mandrel 25, so that it is easy to apply a pulling force to the mandrel 25. In this case, the width of the step 28d of the axial hole portion 46d of the jaw 40 and the mandrel 25 is extremely narrow, and therefore, the small diameter hole portion 46 of the jaw 40 is required to sufficiently apply the small shaft portion 28 of the mandrel 25. Face pressure. The jaw 40 applies a pulling force to the step 28d, and at the same time, applies a higher surface pressure to the thin shaft portion 28. Therefore, the step 28d is not deformed, and the thin shaft portion 28 and the rear end portion 29 can be prevented from being plastically deformed due to the high surface pressure. According to the embodiment of the present invention, the inclination angle αj of the outer circumferential surface 41 of the jaw 52 is smaller than the inclination angle αc of the inner circumferential surface 31 of the jaw 32. The groove 45 of the jaw 40 is after the jaw 40 and the thick portion 43 is a narrow width w1, which is wider than the left side to a width w2. Therefore, the mandrel shaft portion 26 is strongly gripped by the rear end portion 29 at the thin shaft portion 28, and is pulled by a relatively high frictional force with a high surface pressure. The jaw 40 has a small diameter hole 46s having a small inner diameter on the front end side and a large diameter hole 46b having a large inner diameter on the rear end side. A shaft hole step portion 46d is formed between the small diameter hole 46s and the large diameter hole 46b. The shaft hole step 46d of the jaw 40 can abut the step 28d of the mandrel 25 to pull the mandrel 25. The e-clip 40 pulls the step 25d of the mandrel 25, and at the same time, applies a high surface pressure to the thin shaft portion 28 and the rear end portion 29 of the mandrel 25 to pull the mandrel 25 by friction, thereby preventing the heart The step 28d of the shaft 25 is plastically deformed from the thin shaft portion 28.

1‧‧‧Blind rivets

2‧‧‧ rivet body

3‧‧‧ casing

4‧‧‧Flange

5‧‧‧ mandrel

6‧‧‧ mandrel shaft

7‧‧‧ mandrel head

8‧‧‧ gripping department

10‧‧‧Rive fastening device

11‧‧‧ headpiece

11R‧‧‧O-ring

11P‧‧ ‧ sales

12‧‧‧Ep

13‧‧‧ head cover

14‧‧‧Eu clip

15‧‧‧E-clamp thruster

16‧‧‧Retracting head

17‧‧‧ E-clamp locking parts

18‧‧‧Ep clipper spring

19‧‧‧Ball screw

20‧‧‧Blind rivets

22‧‧‧ rivet body

23‧‧‧ casing

24‧‧‧Flange

25‧‧‧ mandrel

26‧‧‧ mandrel shaft

26h‧‧‧breakable part

26c‧‧‧Cylinder

27‧‧‧ mandrel head

28‧‧‧Spindle shaft

28d‧‧‧ step

29‧‧‧ Back end

30‧‧‧Rive fastening device

31‧‧‧ inner circumference

32‧‧‧Ep

33‧‧‧ head cover

35‧‧‧E-clamp thruster

36‧‧‧ Pulling head

37‧‧‧ E-clamp locking parts

38‧‧‧Ep clipper spring

39‧‧‧Ball screw

40‧‧‧E-clip

41‧‧‧ outer perimeter

42‧‧‧ pointed parts

43‧‧‧After the rough

45‧‧‧ slotting

45n‧‧‧Narrow slot

45w‧‧‧ wide slot

45d‧‧‧Slotting

46s‧‧‧Small hole

46b‧‧‧ Large diameter hole

46d‧‧‧Axis hole steps

Part B‧‧‧

C‧‧‧ Section

W1‧‧‧Width

W2‧‧‧Width

Jj‧‧‧ tilt angle

Cc‧‧‧ tilt angle

Fc‧‧‧ diameter of the cylindrical part

Fn‧‧‧diameter of the thin shaft

Fe‧‧‧diameter of the rear end

Figure 1 is a cross-sectional view of a prior rivet fastening device that secures a previous blind rivet. Figure 2 is a front elevational view of a blind rivet comprising a rivet body and a mandrel in accordance with an embodiment of the present invention. Figure 3 is a front elevational view of the rivet body of the blind rivet of Figure 2. Figure 4 is a front elevational view of the mandrel of the blind rivet of Figure 2. Fig. 5 is a cross-sectional view showing a rivet fastening device according to an embodiment of the present invention. Figure 6 is only a cross-sectional view of the jaw and the jaw of the rivet fastening device of Figure 5. Figure 7 is a perspective view of the jaw of the rivet fastening device of Figure 5. Figure 8 is a front elevational view of the jaw of Figure 7. Figure 9 is a left side view of the jaw of Figure 7. Figure 10 is a right side view of the jaw of Figure 7. Figure 11 is a cross-sectional view of the jaw of Figure 7 taken along line A-A of Figure 9. Figure 12 is an enlarged view of a portion C of Figure 8 of the jaw of Figure 7. Figure 13 is an enlarged view of a portion B of Figure 11 of the jaw of Figure 7.

Claims (8)

A rivet fastening device, characterized in that a blind rivet including a mandrel and a rivet body is fastened to a member to be mounted, and has: a pull-in portion that pulls a shaft portion of the mandrel and pulls in; and a head cover for supporting the flange of the rivet body; the pull-in portion has: a pulling head that moves in the axial direction; and a jaw sleeve that is disposed integrally with the pulling head adjacent to the pulling head And an inner circumferential surface having an inner diameter that decreases toward the front end; and an jaw clamp disposed in the outer jaw and having a peripheral surface that abuts against the inner circumferential surface of the outer casing; the outer circumference of the outer jaw The inclination angle of the surface is smaller than the inclination angle of the inner circumferential surface of the above-mentioned jaw jacket. The rivet fastening device of claim 1, wherein the jaw clip comprises two jaw segments, and the slot between the two jaw segments is behind the jaw jaw and the outer portion of the thick portion is narrow. The groove is a wide groove wider than the narrow groove in the front side of the rear thick portion, and the narrow groove and the wide groove form a groove step. The rivet fastening device of claim 1 or 2, wherein the jaw clip has a shaft hole for gripping the shaft portion of the spindle, and the shaft hole has a small diameter hole with a small inner diameter and a rear inner diameter. The large diameter hole is a shaft hole step between the small diameter hole and the large diameter hole. The rivet fastening device of claim 3, wherein the mandrel of the blind rivet fastened by the rivet fastening device comprises a mandrel head at one end and the mandrel portion extending from the mandrel head The mandrel shaft portion has a cylindrical portion, a thin shaft portion whose outer diameter is smaller than the cylindrical portion behind the cylindrical portion, and an outer diameter of the rear portion of the thin shaft portion which is the same as the cylindrical portion, and the thin shaft a step is formed between the portion and the rear end portion, and the pull-in portion is located at a front position. When the blind rivet is provided in the rivet fastening device, the thin shaft portion of the mandrel is disposed in the small diameter hole of the jaw On the inner side, the rear end portion of the mandrel is disposed inside the large diameter hole of the jaw. The rivet fastening device of claim 4, wherein when the pull-in portion is retracted, the axial hole step between the small-diameter hole and the large-diameter hole pulls the step between the thin shaft portion and the rear end portion difference. An jaw clip characterized in that the jaw clip of the rivet fastening device for fastening the mounted member by using a blind rivet comprising a mandrel and a rivet body, the jaw clip comprising two jaw sections, the above two jaw regions The groove between the segments is a narrow groove narrowed behind the above-mentioned jaw, and the narrow portion at the front is a wide groove, and the narrow groove and the wide groove become a groove step. The clip according to claim 6, wherein the jaw clip has an axial hole to grip the spindle shaft portion of the spindle, and the shaft hole is a small diameter hole with a small inner diameter and a rear inner diameter. The large diameter hole is a shaft hole step between the small diameter hole and the large diameter hole. A pull-in portion, characterized in that a blind rivet including a mandrel and a rivet body is fastened to a rivet fastening device of a mounted member and pulled into a pull-in portion of a spindle shaft portion of the spindle, the pull-in portion The utility model has a pulling head which is moved in an axial direction, a jaw sleeve which is arranged integrally with the pulling head adjacent to the pulling head, and has an inner circumferential surface whose inner diameter becomes smaller toward the front end; And disposed in the outer jacket and having a peripheral surface that abuts against the inner circumferential surface of the outer casing; and an inclination angle of the outer circumferential surface of the jaw is smaller than an inclination angle of the inner circumferential surface of the outer jacket.