JPS6314088Y2 - - Google Patents

Description

[Detailed Description of the Invention] A. Field of Industrial Application The present invention relates to a structure for joining a plurality of members, and particularly to a joining device used for joining.

B. Prior Art Conventionally, a plurality of members are connected using threaded members by tapping one of the members to form a female thread, and then screwing and tightening the threaded member into the female thread. Alternatively, when tapping is not performed, a tap pin screw that taps itself is used. However, in the case of sheet metal parts, the former type of tapping is a separate process, and in terms of quality control, it is necessary to check untapped products, which causes high costs. In addition, the method using tatsupin screws requires a large torque to turn the screws, and cannot be used for decorative screws or the like.

Therefore, recently, a member coupling device as shown in FIG. 1 has been used. That is, a circular hole 2 having the same diameter as the root diameter of a coupling screw (not shown) is formed at a predetermined portion of the member 1, and a cut 4 is formed in a part of the peripheral edge 3 of the circular hole 2.
After that, one side of the cut 4 is extruded by an appropriate means to form an inclined surface portion 5 corresponding to the slope of the thread of the coupling screw, and the coupling screw is inserted into the circular shape of the member 1 along the inclined surface portion 5. It is designed to be screwed into hole 2. However, with this, the circular hole 2 will vary due to the cutting error in the notch dimension due to wear of the notch cutting blade, the extrusion dimension error of the inclined surface portion 5 caused by this, etc., and the coupling screw cannot be smoothly inserted into the circular hole 2. The disadvantage was that screws could not be inserted and it took time to connect the parts. In addition, a cutting step for making cuts in the circular hole 2 and an extrusion step for forming the inclined surface portion 5 are required, which results in higher costs and poor workability.

C. Purpose of the invention The purpose of the present invention is to enable screw fitting to be performed with a small torque without performing tap processing on the joining members, and to enable quick and smooth joining of multiple members.

D. Structure of the invention In the present invention, a circular hole having a diameter slightly smaller than the nominal diameter of the screw member is formed in one of the members, and a part of the circumference of the circular hole is formed in one of the members. A pair of protrusions with an inclination for guiding the screw member corresponding to the inclination of the thread of the screw member is formed on the front and back, and the thread is moved spirally along the inclined surface of the pair of protrusions. It is.

E. Embodiment FIGS. 2 to 7 show embodiments of the present invention. In the figure, reference numeral 11 indicates a screw member such as a normal screw or a tatsu pin screw for connecting a plurality of members;
Reference numeral 2 denotes a predetermined member in which the connecting portion is formed to have a wall thickness smaller than the width l of the root 13 of the screw member 11, and the predetermined portion of this member 2 has a screw thread larger than the nominal diameter dimension a of the intermediate portion of the screw member 11. A circular hole 15 having a diameter c obtained by subtracting the height b of the ridge 14 is formed, and symmetrical portions on both sides of the circular hole 15 are press-molded using a press or the like to provide convex portions 16 and 17. is made to protrude on the back side of the member 12, and the other protrusion 17 is made to protrude on the front side. Then, the convex portions 16 and 17 of the member 12
is the helical angle θ of the thread 14 of the screw member 11.
an inclined surface portion 18 for guiding the screw member at the same angle θ;
form 19. Therefore, the screw member 11
When the tip of the screw is inserted into the circular hole 15 and rotated, the screw thread 14 spirally moves along the inclined surface portions 18 and 19 of the convex portions 16 and 17 around the circular hole 15.
The screw member 11 can be screwed straight into the circular hole 15 without wobbling, and moreover, the screw member 11 can be screwed in with a small torque at that time.

FIG. 8 shows the coupling device according to the present invention applied to a lighting fixture, in which a circular hole 15 with protrusions 16 and 17 around it is formed in a predetermined part of a sheet metal member 22 of a main body 21 of a lighting fixture 20, By screwing the screw member 11 into this circular hole 15 in the manner described above, the reflective shade 23
is attached to the main body 21. In this case, if a resin member 25 is fitted onto the head 24 of the screw member 11 as shown in FIG. 2, it can be used as a decorative screw.

F. Effects of the Invention According to the invention, there is no need to perform tap processing on the connecting portions of the members, so that the number of manufacturing steps can be reduced accordingly, and costs can be reduced. Further, since the circular hole for inserting the screw member can be formed in the pressing process during the production of the member, the accuracy of the circular hole is good, the quality is improved, and quality control is facilitated. Further, even screw members, especially tatupin screws, can be screwed in with a small torque, and multiple members that are frequently attached and detached can be easily and quickly connected, and can also be used as a decorative screw.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a conventional coupling device.
2 to 8 show a coupling device according to the present invention, in which FIG. 2 is an explanatory diagram of a screw member, and FIG.
The figure is an explanatory diagram of the main part, FIG. 4 is a perspective explanatory diagram of a member in which a circular hole is formed, FIG. 5 is a sectional view taken along the line A-A in FIG. 4, and FIG. 7 is a sectional view taken along the line CC in FIG. 4, and FIG. 8 is an explanatory view showing an example of application of the connector according to the present invention. 11... Screw member, 12... Member, 15... Circular hole, 16, 17... Convex portion.

Claims (1)

[Scope of utility model registration request] In a device in which a plurality of members are connected by a screw member, a circular hole having a diameter slightly smaller than the nominal diameter of the screw member is formed in one of the members, and the thread of the screw member is formed on the front and back of a part of the circumference of the circular hole. 1. A joining structure for a plurality of members, characterized in that a pair of convex portions having an inclination for guiding a screw member corresponding to the inclination is provided.