JP2008208869A - Countersink rivet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a countersink rivet preventing swelling of a back face of a fixation member when the rivet is press-fitted and fixed and facilitating alignment of a prepared hole of a fastened member to simplify component combination. <P>SOLUTION: The rivet 1 comprises a leg part 4 press-fitted to the prepared hole 11 bored beforehand and a head part 2. The head part 2 is formed to have a countersunk head shape having diameter which is larger than that of the leg part 4 and is small on the leg part side. Since the countersink rivet 1 has the head part diameter at least 5/4 times larger than the leg part diameter, it is unnecessary to form beforehand spot facing having a conical hole shape on the peripheral edge of the prepared hole 11 on the surface of the fixation member. Only by press-fitting the countersink rivet 1 to the prepared hole 11, the rivet 1 can be fixed to the fixation member and the head part surface of the rivet 1 can be made flush with the surface of the fixation member. Thus, this eliminates a work process of forming spot facing and enables reduction in manufacturing cost. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention is a rivet for press-fitting a leg portion to the fixing member from the front side thereof, and when the rivet is fixed to the pilot hole of the fixing member, the material of the peripheral edge of the pilot hole is swelled from the back surface as much as possible. It is related with the countersunk rivet which fixed a fixing member and a to-be-fastened member by overlapping a to-be-fastened member on the back surface of a fixing member, and crimping | curling the front-end | tip of a leg part.

  In recent years, so-called flat-screen televisions such as liquid crystal displays and plasma displays, for which demand is rapidly increasing, are often made of aluminum alloy panels due to their lighter weight configuration, etc., and the display is attached to this for commercialization. Has been. In such a panel, many rivets and insert members are used, and thinning and weight reduction are progressing. However, when fixing each plate material, generally a rivet having a rounded head is used. The plate members are fixed to each other. For this reason, the head protrudes as a protrusion on the surface of the plate material, which becomes an obstacle to the pursuit of thinness.

  In addition, instead of the aluminum alloy plate material, a relatively soft plate material such as a cold-rolled steel plate may be used, but in order to solve the above problem, such a fixing member that performs rivet caulking. It is necessary to use a rivet having a counterbore in the lower hole and a countersunk head in the lower hole to make the surface of the plate material and the flat head surface the same. However, since it is necessary to form a counterbore around the pilot hole in the plate material, this counterbore process must be provided, and the number of work processes is inevitably increased.

Japanese Patent No. 3,706,838 discloses a plate-like component that is overlapped and caulked and fixed using a countersunk rivet. This relates to a reinforcing structure for a coin-carrying disk rotor in a coin hopper type coin payout device built in a gaming machine, change machine, money change machine, vending machine, etc., for paying out a required number of coins. FIG. 5 shows the main part thereof. In FIG. 5, reference numeral 110 denotes a surface cover that reinforces the disc rotor main body 120. The surface cover 110 is formed by plastic processing of a stainless steel plate or other metal plate that is harder and smoother than a coin, and preferably has a constant thickness of about 0.4 mm. A conical countersunk hole 122 is formed in the implantation hole 121 and a dish rivet 101 is press-fitted to integrally attach the surface cover 110 to the surface of the disc rotor main body 120. As described above, the disc rotor body 120 is formed with the conical countersunk hole 122 so that the head 102 of the rivet 101 is flush with the surface cover 110.
Japanese Patent No. 3,706,838

  In order to prevent the head of the rivet thus crimped from protruding, a countersunk head rivet is usually used, and a counterbore (conical countersunk hole) is formed on the work so that the conical seating surface of the rivet is in contact, Caulking is generally performed, but the number of work processes is inevitably increased, which does not lead to a reduction in product cost. Also, by forming the counterbore in this way, burrs are generated in this counterbore forming operation, so it is necessary to remove it, otherwise it will be on the same surface as the workpiece When a thin sheet was pasted, this sometimes broke. Furthermore, when fastening each other's plate-like workpieces in close contact with these rivets, either stack each other's plate material in advance and then press-fit the rivets, or drill a pilot hole in each other's workpieces in advance. After positioning, the rivet is often press-fitted and crimped. In the former case, the work is punched out with the rivet, so the work around the rivet swells, and the back surface is in a swelled state. On the other hand, in the latter case, it is necessary to align the pilot holes of the workpieces in a state where the workpieces are overlapped with each other, which takes a lot of time. In addition, if the center of the pilot hole is shifted even a little, problems such as distortion of the rivet and slight rise of the rivet head occur.

  The object of the present invention is to eliminate such problems and prevent the back surface of the fixing member from bulging as much as possible when the rivet is press-fitted and fixed to the fixing member. It is to obtain a countersunk rivet that simplifies the combination of parts.

  An object of the present invention is a rivet 1 comprising a leg 4 and a head 2 that are press-fitted into a prepared hole 11 that has been drilled in advance, and the head diameter is larger than the leg diameter and the leg side has a smaller diameter. This is accomplished by providing a countersunk rivet that has a head 2 of at least 5/4 times the diameter of the leg.

  Another object of the present invention is a rivet 1 comprising a leg 4 and a head 2 that are press-fitted into a pilot hole 11 that has been drilled in advance, the head diameter being larger than the leg diameter and having a smaller diameter on the leg side. A head-shaped head 2 is formed, and the head diameter is at least 5/4 times the diameter of the leg. On the other hand, the rivet 1 is inserted into a pilot hole 11 formed in the fixing member 10 and the fixing member 10 The head surface is flush with the surface, and the leg 4 is press-fitted and fixed so as to protrude from the fastened member 20 fixed to the back surface 10a of the fixing member 10, and the rivet 1 is fixed to the fixing member 10 and the rivet To provide a countersunk rivet in which the leg 4 of the rivet 1 is inserted into the pilot hole 21 of the fastened member 20 in a state where the 1 leg 4 protrudes from the fixing member 10 so that the tip of the leg is caulked. Is also achieved.

  Furthermore, in the dish-head rivet having these configurations, the head diameter is set to a size of 5/4 to 6/4 with respect to the leg diameter, so that the material swells on the back surface of the fixing member as a workpiece. The output is eased as much as possible. Moreover, since the rivet has a hardness greater than the hardness of the fixing member 10 and is configured to crush the peripheral edge of the pilot hole of the fixing member 10 during press-fitting, the material of the fixing member swells toward the center of the pilot hole and presses the rivet Therefore, the back surface of the fixing member hardly bulges.

  According to the present invention, it is unnecessary to previously form a counterbore-shaped counterbore on the periphery of the pilot hole on the surface of the fixing member, and the rivet can be fixed to the fixing member simply by press-fitting the countersunk rivet into the pilot hole. The head surface of the rivet can be flush with the surface of the fixing member. For this reason, the work process of forming the spot face is eliminated, and the product cost can be reduced. In addition, there are no burrs generated at the time of spot face formation, and there is no need to remove them, and even if a thin sheet is pasted on the surface of the fixing member, it is also possible to eliminate that the burrs are broken by burrs. Furthermore, when caulking and fixing with a plate-like member to be fastened on the back surface of the fixing member, there is almost no bulging portion on the back surface of the fixing member, so that there is a gap between the fixing member and the member to be fastened. Can be caulked and fixed without overlapping. In addition, the countersunk rivet is press-fitted and fixed in advance to the lower hole of the fixing member so that the leg portion protrudes, and then the leg portion of the rivet is inserted into the lower hole of the member to be fastened, and the leg portion is caulked. Therefore, the prepared member can be easily aligned with the fixing member with respect to the fixing member, and the center of the prepared hole is not shifted. As a result, the rivet is not distorted and the rivet head is not lifted. In addition, even when the fixing member is moved away and fixed to the member to be fastened there, there are specific effects such as easy alignment with the member to be fastened.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. In FIG. 1, reference numeral 1 denotes a head 2 having a seat surface 3 in which the surface of the head 2 is flat and the leg portion is smaller in diameter than the head diameter, and a leg portion having a diameter smaller than that of the head 2. This is a countersunk rivet integrated with 4. The head diameter is at least 5/4 times the leg diameter, and at most the head diameter is set to 5/4 to 6/4 of the leg diameter. . By setting in this way, the material of the member may bulge from the back surface 10a of the fixing member 10 even if the leg portion 4 is first press-fitted and fixed to the prepared hole 11 that is previously opened in the fixing member 10. It is designed not to occur as much as possible.

  In addition, the conical seat surface 3 of the countersunk rivet 1 has an inclination angle (θ) of about 45 °, so that the material on the surface side of the fixing member 10 is the center of the pilot hole of the fixing member 10. The rivet 1 flows to the side and presses the peripheral surface of the press-fitted rivet 1, so that the rivet 1 is integrally fixed to the fixing member 10. At this time, since the head outer peripheral diameter of the rivet 1 is only slightly larger than the leg diameter, there is almost no material flow to the back surface 10a of the fixing member 10. In addition, the inclination angle (θ) of the conical seat surface 3 can be fixed with a smaller pressure input by making it larger than 45 °. On the other hand, the rivet 1 has a sufficient caulking allowance to be caulked on the back surface 20a of the fastened member 20 by making it longer than the sum of the thickness of the fixing member 10 and the thickness of the fastened member 20 fixed thereto. The length is set, and the tip thereof is chamfered to facilitate insertion into the pilot holes 11 and 21.

  Further, the rivet 1 is set so as to have a hardness greater than that of the fixing member 10 and is configured to crush the peripheral hole of the fixing member 10 at the time of press-fitting. Thus, it is sufficient that the hardness of the rivet 1 is larger than the hardness of the fixing member 10, that is, if the seat surface 3 of the rivet 1 is sufficient to crush the peripheral hole of the fixing member 10, the hardness is particularly limited. Is not to be done. In this embodiment, for example, since the hardness of the fixing member 10 is Hv 80 to Hv 100, the hardness of the rivet 1 is set to Hv 130 or higher.

  In the operation of fixing the countersunk rivet 1 to the fixing member 10, as shown in FIG. 2, the fixing member 10 having a pilot hole 11 that is drilled in advance according to the leg diameter of the rivet 1 is prepared. As shown in FIG. 3, the leg portion 4 of the rivet 1 is press-fitted into the prepared hole 11 from the surface side of the fixing member 10. Accordingly, the press-fitted rivet 1 is immersed in the fixing member 10 while the seating surface 3 of the head 2 crushes the periphery of the pilot hole 11, and the head surface of the rivet 1 is flush with the surface of the fixing member 10. The leg portion 4 is fixed in a state where it protrudes from the back surface 10a of the fixing member 10 by a predetermined amount.

  As described above, in the rivet 1 including the leg portion 4 and the head portion 2 that are press-fitted into the prepared pilot hole 11, the rivet 1 is placed in the prepared hole 11 formed in the fixing member 10 on the surface of the fixing member 10. After the leg portion 4 is press-fitted and fixed with the leg portion 4 having a length sufficient to protrude from the fastened member 20 fixed to the back surface 10a of the fixing member 10 with the head surface being in the same plane. 4, the leg portion 4 of the rivet 1 is positioned in the prepared hole 21 of the fastened member 20. Thereafter, the leg 4 of the rivet 1 is inserted into the pilot hole 21 of the fastened member 20 and the tip of the leg is caulked. As a result, as shown in FIG. 1, the fastened member 20 is tightly fixed to the fixing member 10 without causing a gap. The rivet 1 used in this embodiment may be a so-called hollow rivet in which a hollow hole is provided in the leg portion 4, or a solid rivet without a hollow hole.

It is a principal part sectional front view showing an embodiment of the invention. It is a principal part cross-sectional front view which shows the relationship between a rivet and a fixing member. It is a principal part cross-sectional front view which shows the state which press-fits a rivet to a fixing member. It is a principal part cross-sectional front view which shows the state press-fitted in a to-be-fastened member. It is a principal part cross-sectional front view which shows a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rivet 2 Head 3 Seat surface 4 Leg 10 Fixing member 10a Back surface 11 Pilot hole 20 Fastened member 20a Back surface 21 Pilot hole

Claims (4)

  A rivet comprising a leg (4) and a head (2) that are press-fitted into a pre-drilled pilot hole (11), the head diameter being larger than the leg diameter and having a countersunk head shape with a smaller diameter on the leg side. A countersunk rivet characterized by forming a head and having a head diameter of at least 5/4 times the leg diameter.   A rivet consisting of a leg and a head press-fitted into a pre-drilled hole, the head diameter is larger than the leg diameter, and a countersunk head is formed with a smaller diameter on the leg side. Is formed to be at least 5/4 times the diameter of the leg portion, and on the other hand, the rivet (1) is in a prepared hole formed in the fixing member (10), and the head surface is flush with the surface of the fixing member. The leg portion is press-fitted and fixed so as to protrude from the fastened member (20) fixed to the back surface (10a) of the fixing member, and the rivet is fixed to the fixing member and the leg portion of the rivet protrudes from the fixing member. A countersunk rivet characterized in that a leg portion of a rivet is inserted into a prepared hole (21) of a member to be fastened so that a tip end of the leg portion is caulked.   3. The countersunk rivet according to claim 1, wherein the head diameter is set to 5/4 to 6/4 of the leg diameter. 4. The countersunk rivet according to claim 1, wherein the rivet has a hardness larger than that of the fixing member, and crushes the peripheral hole of the fixing member when pressed.

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