JPH0736176Y2 - Bolt pin for rivet gun - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bolt pin for a rivet hammer that is driven into a steel plate or the like for connecting metal fittings to the steel plate or the like at a construction site.

[0002]

2. Description of the Related Art At a construction site, in order to connect a metal plate to a steel plate or the like, a bolt pin is driven into the steel plate or the like with a rivet gun, and the metal screw is used to connect the metal plate.

An example of a bolt pin 1 for a rivet gun conventionally used in such a case will be described with reference to FIG. 6, in which a sharpened tip 2 side is a driving portion 3 and a base end 4 is formed. The side is made larger in diameter than the driving part 3, and a male screw part 5 is formed around the base end 4 side which is made large in diameter.

As shown in the sectional view of FIG. 7, knurls 6 having irregularities in the longitudinal direction are formed around the driving portion 3. The height of the unevenness of the knurl 6 has the same height over the entire length of the driving part 3.

When a metal fitting is connected to a steel plate by using the stud hammer bolt pin 1, a sharp tip of the stud hammer bolt pin 1 is used as shown in FIG. When 2 is driven into the steel plate 7, the portion of the knurl 6 enters into the steel plate 7, the tightening pressure due to the contraction of the steel plate 7 is applied to the knurl 6, and the bolt pin 1 for the rivet gun cannot come off from the steel plate 7.

Next, the female screw 8 of the connecting metal fitting 9 having the female screw 8 engraved on the inner surface on one end side is screwed into the male screw portion 5 of the bolt pin 1 for the rivet gun to connect the connecting metal fitting 9, and the connecting metal fitting 9 is connected. The male screw rod 10 was screwed into the female screw at the other end.

[0007]

[Problems to be solved by the invention] Bolt pin 1 for rivet gun
When the unevenness of the knurl 6 around the driving portion 3 is formed, pressure is applied to the concave portion by a molding roll or the like to make the concave, and the convex portion is formed by the plastic deformation by the pressure. Internal stress due to strain is generated in the knurled portion and the knurled end portion 11 on the base end 4 side, and when the stud gun bolt pin 1 is driven into the steel plate 7, the pull-out force is exerted on the connection fitting 9 and the male screw rod 10. In some cases, the bolt pin 1 for a rivet gun may break at the knurl 6 portion or the knurl end portion 11 when it is applied.

An object of the present invention is to provide a bolt pin for a rivet gun which eliminates the above-mentioned conventional drawbacks and prevents breakage at a knurl portion or a knurl end portion.

[0009]

DISCLOSURE OF THE INVENTION A bolt pin for a rivet driving gun according to the present invention is provided with a driving portion on the distal end side and a male screw portion on the proximal end side, and the distal end side is high and the proximal end side is around the driving portion. It is characterized in that a knurl in the longitudinal direction is formed in a shape in which the height gradually decreases as it goes to.

[0010]

The knurling formed in the longitudinal direction around the driving portion has a high tip side and a gradually lower height toward the base side, so that the knurl portion and the knurl end portion 11 may be distorted by distortion. Internal stress is dispersed and no longer concentrated.

[0011]

EXAMPLES Next, examples of the present invention will be described.

FIG. 1 is a side view of an embodiment of the present invention. A bolt pin 20 for a rivet driving gun according to the present invention is similar to the conventional bolt pin 20.
The diameter of the base end 23 side is larger than that of the driving portion 22, and a male screw portion 24 is formed around the base end 23 side having the large diameter.

A knurl 25 having irregularities in the longitudinal direction is formed around the driving portion 22. This knurled 25
Is not the same shape over the entire length as in the past,
As shown in FIG. 2, the height of the unevenness is high on the distal end 21 side, and as shown in FIGS. 3 and 4, the height of the unevenness gradually decreases toward the base end 23 side. In the portion 26, the knurl 25 is naturally eliminated.

When a metal fitting is connected to a steel plate using the stud hammer bolt pin 20, a stud hammer (not shown) is used as shown in FIG.
When the sharpened tip 21 is driven into the steel plate 7, the portion of the knurl 25 enters the steel plate 7, and the tightening pressure due to the contraction of the steel plate 7 is applied to the knurl 25. The knurl 25 formed around the driving part 22 has a tip 21.
The knurled portion is formed into a shape in which the height of the unevenness is high on the side, and the height of the unevenness gradually decreases toward the base end 23 side, and therefore tightening pressure is applied to the steel plate 7 due to shrinkage of the steel plate 7. The portion 25 exhibits a wedge effect on the steel plate 7, and the bolt pin 20 for the rivet gun cannot come off from the steel plate 7.

Next, the female screw 8 of the connecting metal fitting 9 having the female screw 8 engraved on the inner surface on one end side is screwed into the male screw portion 24 of the bolt pin 20 for a rivet gun to connect the connecting metal fitting 9, and the connecting metal fitting 9 is connected. The male screw rod 10 is screwed into the female screw at the other end.

[0016]

EFFECTS OF THE INVENTION In this invention, the knurl 25 formed around the driving portion 22 is formed in a shape in which the tip 21 side is high and the height is gradually lowered toward the base end 23 side. The internal stress due to the strain when the convex portion is formed by the plastic deformation caused by the pressure is depressed by a molding roll or the like to gradually decrease toward the base end 23 side, and the knurl 25 portion and the knurl end portion are formed. 26
There is an effect that the bolt pin 20 for the rivet gun is not broken and the stable strength is obtained.

Further, since the knurling 25 is formed in a shape in which the tip end 21 side is high and the height is gradually lowered toward the base end 23 side, the stud hammer bolt pin 20 driven into the steel plate 7 is hard to come off and is firmly fixed. And seeing the height of the unevenness of the knurl 25 in the part exposed from the steel plate 7,
This has the effect of determining the driving depth of the driving portion 22 with respect to the steel plate 7.

[Brief description of drawings]

FIG. 1 is a side view of an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a sectional view taken along line III-III in FIG.

4 is a sectional view taken along the line IV-IV in FIG.

FIG. 5 is a side view showing a partial cross section of a use state of an embodiment of the present invention.

FIG. 6 is a side view of a conventional one.

7 is a sectional view taken along line VII-VII in FIG.

FIG. 8 is a side view showing a partially used cross-section of a conventional one.

[Explanation of symbols]

 20 bolt pin for rivet gun 21 tip 22 driving part 23 base end 24 male screw part 25 knurling

Claims (1)

[Scope of utility model registration request] 1. A longitudinal direction having a shape in which a driving portion is provided on the distal end side and a male screw portion is provided on the proximal end side, and the periphery of the driving portion is higher at the distal end side and gradually lowers toward the proximal end side. A knurled bolt pin for a struck gun.