JPS6224809Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial field of application] This invention is a screw grommet (hereinafter referred to as "a screw grommet") in which a metal washer is inserted into the leg of the grommet body, for use in round holes drilled in car body panels, etc. , simply called grommets).

[Prior art] Until now, parts have been attached to steel plates such as car body panels by welding nuts to the steel plate and fixing them with screws, but by using flanged grommets, etc., the welding process can be simplified. This method saves labor and greatly improves workability by working from one direction, and square hole grommets have become widely used as an alternative to weld nuts.

In addition, the uses of grommets as resin fasteners are not only for the purpose of fastening, but also for a wide range of purposes, such as locking, waterproofing, part of spacers, and connecting shafts of rotating bodies. There are many types that take advantage of the material's characteristics such as good workability, light weight, elasticity, and wear resistance.

Depending on the use of such grommets, the shapes of the flange and legs vary, and the shapes and dimensions of the mounting holes also vary, but most grommet grommet grommet have square-shaped legs for the purpose of preventing rotation of the grommet body. be. For this reason, square holes had to be made on the steel plate side of vehicle body panels, which was a factor in increasing costs in the press working process.

On the other hand, since round holes for other clips cannot be shared, the number of types of vehicle body panels has to be increased.

[Purpose of the invention] The purpose of this invention is to make the cross-sectional shape of the leg of the grommet body round, and to carve a threaded groove in the grommet body, so as to be used for round holes drilled in car body panels, etc. By inserting the metal washers provided, it is possible to prevent rotation within the round hole, and the holes drilled in the vehicle body panels, etc., can be easily post-processed as round holes, and the vehicle body panels, etc. can be made common. An object of the present invention is to provide a grommet for a round hole that can be used.

[Structure of the invention] That is, in this invention, a tapered hole is formed in the center of the circular flange and a substantially conical leg protruding from the lower side of the flange, and this leg is axially rotated. The grommet body is divided into multiple parts by slotted grooves, and a pair of small protrusions are provided in the diametrical direction on the upper part of the conical body with thread grooves carved on the outer surface.
A cutting groove is provided in the center of the body so that it can be bent freely, and a pair of small protrusions are fitted into the slotted grooves to form a screw consisting of a metal washer fitted into the leg of the grommet body. It's a grommet.

[Example] An example of this invention will be described below with reference to the drawings.

First, as shown in FIG. 1, 1 is a grommet body made of semi-hard synthetic resin such as nylon, and 2 is a metal washer, which is fitted into the base of the grommet body 1. Grommet body 1 shown in FIGS. 2 and 3
A substantially conical leg portion 11, which is divided into two parts by a slit groove 1b, is integrally protruded from the center of the lower part of the circular collar 1a. A tapered hole 1c is formed in the center of this grommet body 1, and the inner diameter of the taper hole 1c is equal to or slightly smaller than the lower thread diameter d of the tapping screw 5 to be inserted. It is set as follows. On the other hand, the aforementioned conical leg 1
The diameter in the axial direction of the leg 1 is set to be maximum at the base of the flange, and is slightly tapered toward the leg tip 1d. Further, in the lower collar 1f of the circular collar 1a, the annular groove is recessed to a predetermined depth to provide a second lower collar 1e.

Furthermore, as shown in FIGS. 4 and 5, a metal washer 2 is inserted into the annular groove below.
is available. Thread grooves 2d of a predetermined pitch are cut into the conical outer surface 2a of the metal washer 2, and the height of the metal washer 2 is approximately half the inner diameter. Further, a pair of small projecting pieces 2c, 2c are provided from the inside of the upper part of the body of this metal washer 2 to engage with the root of the slotted groove 1b, and at the center position of the body of this metal washer 2, a pair of small projecting pieces 2c, 2c are provided. A groove 2b is provided so that it can be bent freely.

To summarize, this grommet has a tapered hole 1c in the center of the circular flange 1a and a substantially conical leg 11 protruding from the lower side of the circular flange 1a.
Grommet main body 1 is formed by drilling and dividing this leg portion 11 into a plurality of parts by an axial slot groove 1b.
A pair of small projecting pieces 2c are provided in the upper part of the conical body 11 having a threaded groove 2d carved on the outer surface in the diametrical direction, and a cutting groove 2b is provided in the center of the body 11.
is provided so that it can be bent freely, and its pair of small protrusions 2c
and a metal washer 2 which is fitted into the slotted groove 1b and inserted into the leg portion 11 of the grommet main body 1.

[Function] Next, to explain the function, as shown in FIG. At the same time, the grommet with the metal washer 2 inserted into the leg part 11 of the grommet main body 1,
When screwed into the mounting round hole of a steel plate 3 such as a vehicle body panel, as shown in FIG. The lower flange 1f of the main body 1 is connected to the steel plate 3
The rotation stops when it comes into contact with the surface.

An article 4 is placed on the upper surface of this circular collar 1a, and after the holes are aligned, the tapping screw 5 is screwed into the tapered hole 1c of this leg portion 11.

At this time, as described above, the thread groove 2d carved on the outer surface of the metal washer 2 is screwed into the inner periphery D of the round hole of the steel plate 3, and further,
By fitting the small protrusion 2c of the metal washer 2 into the slotted groove 1b of the grommet body 1,
The grommet main body 1 can be screwed with the tapping screw 5 without rotating idly.

Thus, the aforementioned leg portions 11 are forcibly expanded in the outer radial direction by the tapped screws 5 inserted therein. Furthermore, on the inner periphery D of the round hole of the steel plate 3,
The thread groove 2d on the outer periphery of the metal washer 2 is brought into close contact with a large radial force, and the fastening of the adherend 4 by this grommet is completed.

[Effect of the invention] By adopting the above-mentioned screw grommet with a metal washer inserted into the grommet body, square holes for insertion, which were conventionally required to be drilled, can be replaced with the above-mentioned steel plate panels, etc. This has the advantage that a general round hole or drilled hole for mounting can be used.

In this way, with the grommet screwed into the round hole of the steel plate such as the car body panel, the desired adherend is placed on the grommet, and then the grommet body and the metal washer are tightened by tightening the tapping screw with a tool. There is no phenomenon of idle rotation, and it is securely installed and can be fixed without loosening. As described above, this fastener has all the requirements for a resin fastener, and has great practical value as it allows desired fastening to be performed extremely quickly and reliably with just two simple operations.

[Brief explanation of drawings]

The drawing shows one embodiment of this invention.
The figure is a perspective view of this grommet, Figure 2 is a central sectional view of the grommet body, Figure 3 is a bottom view of the grommet body, Figure 4 is a plan view of the metal washer, and Figure 5 is a central sectional view of the metal washer. FIG. 6 is a cutaway side view of the main parts of the grommet and the metal washer, and FIG. 7 is a vertical cross-sectional view showing the fastened state of the grommet, etc. 1... Grommet body, 1a... Circular collar, 1b
...Slotted groove, 1c...Tapered hole, 11...Legs, 2...Metal washer, 2a...Outer surface, 2c
...Small projecting piece, 2d...Thread groove, 3...Steel plate such as car body panel, 4...Adhesive, 5...Tapping screw.

Claims (1)

[Scope of utility model registration request] A grommet body has a tapered hole formed in the center of the circular flange and a substantially conical leg protruding from the lower side of the flange, and the leg is divided into a plurality of parts by slit grooves in the axial direction. A pair of small protrusions are provided in the diametrical direction on the upper part of the conical body with a threaded groove on the outer surface, and a cutting groove is provided in the center of this body to make it bendable. A screw grommet comprising a small protrusion fitted into the slot and a metal washer fitted into the leg of the grommet main body.