JPH06260B2 - Stamping nut manufacturing method - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screwing nut for fixing at least two members, and more particularly to a stamping nut that can be easily formed only by pressing.

[Conventional technology]

A conventional nut is a screw that is formed by cutting a rod-shaped body that has the same shape as the outer shape of the nut, or by cutting and forging a forged product and then tapping it inside to screw it into the screw. Forming a groove.

Further, the simple nut forms a thread groove in which a screw is screwed by erecting a self tap on the plate-shaped body. In this case, the plate-shaped body needs to have a thickness of at least 3 pitches of the screws or more. .

In addition, a simple nut that uses a thin plate is burred by a press, and a tap is added to the bent portion where the apparent plate thickness is increased.
In the metal plate fastening tool and the manufacturing method thereof disclosed in Japanese Patent No. 3568, holes and slits are punched in a metal plate by a round punch. After that, the metal plate is pressed so that a step is formed in the slit by one pitch of the screw.

[Problems to be Solved by the Invention]

The nut manufacturing process includes a cutting process for cutting and forming each of the rod-shaped members forming the outer shape of the nut, a drilling process for forming a hole in the center of the rod-shaped member, and a tapping process for setting a screw on the inner wall of the hole. That is, a completely different kind of processing process is required. Moreover, the speed of tapping for finishing the nut has already reached the limit due to the spiral cutting of the screw even if the speed is increased by using an automatic machine. Therefore, it was difficult to provide a cheaper nut.

Further, as an inexpensive fixing method, a self-tapping tapping screw that does not use a nut has been developed. However, in the case of the self-tapping type, the metal plate on the tapping side has a thickness equivalent to 3 pitches of the screw, pre-processing to make a taper that makes it easy to set up the tapping on the screw side, and blade processing on the tapping screw itself. Need to be applied.

Therefore, the self-tapping type not only has a high cost on the screw side, but also has a problem in the thickness on the metal plate side.

Further, the self-tapping type fixing method has an advantage that it can be used for a plate material such as a plastic which is easily tapped. However, when the self-tapping type fixing method was applied to a plate material such as plastic, if it was repeatedly fastened and unfastened, tapping started from a position different from the original, and eventually it became a stupid screw. .

Therefore, the self-tapping type fixing method has a problem that it cannot be used in a place where repeated insertion and removal are performed.

Further, as an inexpensive nut, there is one in which a tap is erected on a plastic member. The taps erected on such a plastic member can maintain the strength by having a larger tap pitch than the metal member. Therefore, in order to tap the plastic member,
The plastic member needs to have a certain thickness, and the plastic itself, and the metal plate fastening tool and the manufacturing method thereof in Japanese Patent Publication No. 43-23568 have a pre-opened circular shape. By pressing the part, a screw thread that fits one pitch of the screw is made.

When a nut is manufactured from such a circular opening, the metal plate is deformed by one step. That is, the nut molded by such a method is not circular. Therefore, a slit is provided so that the nut can be made as close as possible to the circular shape, and the slit portion makes the nut as circular as possible.

However, small diameter precision nuts had the decision that rotation for tightening would not proceed smoothly unless they were the same circular shape as the screw.

Therefore, the above technology could not be spread as an actual product.

The present invention is for solving the above problems,
An object of the present invention is to provide a stamping nut which is easily formed only by press working and whose screw groove is not broken even if the screw is repeatedly removed and inserted many times.

Another object of the present invention is to provide an inexpensive stamping nut having a strong tightening force.

Another object of the present invention is to provide a stamping nut made of a metal plate member and a plastic member.

A further object of the present invention is to provide a method for manufacturing a stamping nut by a pressing process only.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, a method of manufacturing a stamping nut according to the present invention includes a step portion 1 on a strip-shaped metal plate body.
A step 16 of forming an opening 18 having an incomplete circle 17 and at least one cut groove 20 or 22 cut in a direction opposite to the center of the opening 18 from the opening 18; And the lower inclined portion 4 of the screw thread 6 which is formed in the vertical direction and corresponds to one pitch of the screw 1 to be screwed.
Of the inclined portions 14 and 15 having a slidable contact with the entire surface of the above, and a peripheral portion 19 of the opening 18 so as to come into contact with the root 7 of the screw.

[Action]

The present invention focuses on combining a non-circular opening and a slit in order to solve the drawback that the conventional plate-shaped fastener cannot be smoothly tightened.

By adopting such a manufacturing method, it has been possible to complete a nut made of a metal plate, which has not been realized for many years.

In particular, the stamping nut manufacturing method of the present invention does not need to use any different processing means such as cutting, cutting, forging, drilling or tapping of the outer shape, and continuously performs only a series of press workings. As a result, a highly reliable and inexpensive stamping nut can be provided.

〔Example〕

FIG. 1 is an explanatory view of a usage state of a stamping nut according to the present invention, FIG. 2 is an explanatory diagram of a stamping nut according to the present invention, and FIG. 3 is a stamping nut according to the present invention.
FIG. 4 is a process explanatory diagram, and FIG. 4 is a second process explanatory diagram of the stamping nut in the present invention.

First, manufacturing of the stamping nut according to the present invention will be described in the order of steps.

The plate-shaped member that becomes the stamping nut is, for example, copper,
A metal plate such as phosphor bronze, aluminum, brass, or an alloy thereof, or a strip material made of plastic is processed by a press die (not shown). For example, as shown in FIG. 3, an incomplete circle 17 having a step 16 is punched out in the strip material to form an opening 18 as shown in FIG. In addition, in FIG. 3 and FIG.
Although it is cut into a complete nut state, it is actually cut by the press as one or several continuous nut rows after the last step is completed.

Next, for example, four cut grooves 20 to 23 are provided outward from the center of the opening 18 by another press die (not shown).

At least one cut groove 20 to 23 may be provided. The opening 18 and the cut grooves 20 to 23 can be formed by the same process.

Thereafter, the peripheral edge portion 19 of the opening 18 is pressed from a portion indicated by a dotted line 24 in FIG. 4 by a press die (not shown) other than the above, and the inclined portions 14, 14 ', 1 are pressed, for example.
Mold 5,15 '. The inclination angle of the inclined portions 14 to 15 ′ is the same as the inclination of the thread 6 screwed into the stamping nut 11. Therefore, as shown in FIGS. 1 and 2, the slanted portion 14 and the slanted portion 15 '.
In and, the mold is formed so that the step portion 16 is formed in the height direction. In other words, as described above, the opening 18 is not a perfect circle but an incomplete circle 17 having the step portion 16. Therefore, after being pressed by the mold, the opening 18 with respect to the center of the screw 1 in the traveling direction is pressed. Make it a perfect circle. The cut grooves 20 to 23 work effectively in order to eliminate an unreasonable force when molding a perfect circle with respect to the center of the screw 1 in the traveling direction and to facilitate the rise of the inclined portions 14 to 15 '. To do.

The length relationship of the stamping nut 11 thus manufactured is as follows. That is, as shown in FIG. 2, the horizontal portions 12 and 13 are on the same horizontal plane, and the length of the stamping nut 11 in the cross section is equal to that of the horizontal portion 12 and the inclined portion 14, and the horizontal portion 13 and the inclined portion 14. It is the same as the one to which the part 15 is added.

That is, in FIG. 2, a + b = c + d.

Further, the inclination angles of the inclined portions 14 and 15 match the inclination of the thread 6 of the screw 1.

Further, since the peripheral edge portion 19 of the opening 18 is 90 ° because it is a portion cut by the press, it does not normally coincide with the angle at the root 7 of the screw. However, a part of the peripheral edge portion 19 of the opening 18 is made to be substantially in contact with the inclined portions 3 and 4 at the root 7 of the screw.

The screw 1 is inserted into the opening 18 of the stamping nut 11 molded as described above, and is rotated by inserting a driver (not shown) into the slot groove 5 and turning the driver. The screw 1 used in the present invention may have a plan shape or a square hole shape in addition to the screw having the slit groove 5. The member A and the member B are sandwiched between the screw head 2 and the stamping nut 11. In this case, a washer can be inserted. Further, when the screw 1 is rotated and tightened, the peripheral edge portion 19 of the stamping nut 11 is
Is lifted upward by the upper inclined portion 3 of the screw 1.
At the same time, the inclined portions 14 and 15 are attached to the lower inclined portion 4 of the screw 1.
A force that spreads in the left-right direction in FIG.

However, unless the stamping nut 11 is cracked in the horizontal direction and destroyed, the inclined portions 14 and 15 firmly adhere to each other along the lower inclined portion 4 of the screw 1 due to the reaction force of the members around the nut hole.

Although not shown in FIG. 1, a part of the horizontal portions 12 and 13 of the stamping nut 11 is bent upward or is extrusion-molded, and the portion is cut into the member B, or the member B is previously cut. The rotation of the stamping nut 11 can be stopped by pushing it into the formed recess.

Furthermore, a large number of irregularities can be provided on the horizontal portions 12 and 13 of the stamping nut 11 so that the stamping nut 11 also serves as a washer. The processing method for serving as both the rotation stopper and the washer can be performed at the same time as the press for forming the nut.

In addition, when molding a plastic member by pressing,
To increase the strength, increase the pitch,
Alternatively, cracking can be prevented by considering heating during press molding. The plastic member can be molded by injection molding other than pressing.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments. Various design changes can be made without departing from the present invention described in the claims.

For example, the metal plate member described in the present specification need not necessarily be provided with one stamping nut. That is, it includes a plate-shaped member or a member having a complicated shape other than the plate-shaped member, or a case-shaped member or the like formed with at least one stamping nut.

Further, the material of the plastic member may be replaced with the metal plate member, and the stamping nut corresponding to the screw diameter, pitch, reverse screw and the like can be arbitrarily changed.

Furthermore, it is also possible to reverse the orientation of the ramps of the stamping nut so that they are upwards, or the ramps are upwards and downwards.

In this case, when the rivet is tightened, the inclined portion of the stamping nut is bent in the expanding direction.

Therefore, in the stamping nut as described above, if the fixed member is chamfered with the same inclination as the inclined portion of the stamping nut, even if the rivet is tightened, the inclined portion that is about to spread will contact the chamfered portion. Because it touches, it can be fixed without spreading.

[Effects of the Invention] According to the present invention, compared with a conventional nut that requires different types of processing such as cutting, tapping and cutting.
The nut is molded by only several types of continuous pressing,
Moreover, when tightening the screw to the stamping nut,
A force that narrows the opening of the inclined portion works, and a stamping nut having a strong tightening force can be provided at low cost.

Further, according to the present invention, despite having a simple structure, the stamping nut is a highly reliable stamping nut that does not become unusable due to multiple uses unlike a self-tapping nut, and can be used any number of times. Can be provided.

[Brief description of drawings]

FIG. 1 is an explanatory view of a usage state of a stamping nut according to the present invention, FIG. 2 is an explanatory diagram of a stamping nut according to the present invention, and FIG. 3 is a stamping nut according to the present invention.
FIG. 4 is a process explanatory diagram, and FIG. 4 is a second process explanatory diagram of the stamping nut in the present invention. 1 ... screw 2 ... screw head 3 ... upper sloping part 4 ... lower sloping part 5 ... slitting groove 6 ... thread ridge 7 ... screw bottom 9 ... pitch 11 ... stamping nut 12,13 ... horizontal part 14,14 ', 15 , 15 '... Inclined portion 16 ... Step portion 17 ... Incomplete circle 18 ... Opening 19 ... Peripheral portion 20 to 23 ... Cut groove 24 ... Dotted line

Claims (1)

[Claims] 1. A step of forming an opening having an incomplete circle having a step portion in a strip-shaped metal plate and at least one cut groove cut from the opening in a direction opposite to the center of the opening. And the stepped portion is formed in the vertical direction and the screw 1 to be screwed
A stamping nut, comprising: a section corresponding to the pitch, an inclined section having an angle of sliding contact with the entire lower inclined section of the screw thread, and a step of press-molding the peripheral edge section of the opening so as to contact the root of the screw. Manufacturing method.