JP2003290861A - Form rolling die of deep groove screw, and method for manufacturing deep groove screw - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a form rolling die for forming a male screw and a deep groove in one step without deforming threads of the male screw, and manufacturing a spiral screw with deep groove at a low cost. <P>SOLUTION: The form rolling die comprises a fixed die 12 and a movable die 13, and projecting bars 14 for forming the deep groove of an acute angle provided over the entire surface at predetermined intervals and projecting bars 15 for forming the male screw of a gentle angle of the height smaller than the projecting bars 14 for forming the deep groove in a range reaching a rear end from the middle of the form rolling surface are protruded from the form rolling surfaces of the fixed die 12 and the movable die 13 facing each other. The projecting bars 15 for forming the male screw are gradually wider toward the rear end, and thread grooves 17 formed between the projecting bars 15 are deep first and gradually shallow toward the middle thereof, and the depth is unchanged from a terminating end to the middle thereof. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a die for rolling a screw with a deep groove used for joining timber in a wooden construction, and a method for manufacturing a screw screw using this die.

[0002]

2. Description of the Related Art A screw screw used for joining timber has less resistance when screwed in and can be smoothly screwed in, and does not loosen even after external impact or vibration after fastening. , Good anti-loosening function is required.

As such a screw screw, the applicant of the present invention has proposed a screw screw with a deep groove in JP-A-11-62934.

This deep grooved screw screw a is shown in FIG.
As shown in (C) and FIG. 6, the blank portion 4 is left on the side of the head 1 on the outer peripheral surface of the shaft portion 3 having the head 1 at one end and the tip 2 at the other end, and the range from the middle position to the tip is reached. A structure is provided in which a male screw 5 is provided, and a vertical groove 6 deeper than the valley of the screw thread is provided so as to intersect with the male thread 5.

Such a deep grooved screw screw a
Means that the male screw 5 pierces a hole having a diameter equal to the root diameter, and a screw thread bites into the periphery of the hole, and the groove provided in the screw thread of the male screw 5 enters while cutting the fiber of the wood at the time of screwing in, and chips are generated. Since it is housed in the vertical groove 6, there is an effect that the screwing operation can be performed smoothly, and after the fastening, the wood fiber bites into the vertical groove 6 to obtain the loosening prevention function.

[0006] Usually, a screw screw for wood uses a pair of symmetrical rolling dies each having a ridge for forming a male screw on the opposite surface, and a rivet under the screw fed between the dies is sandwiched. Then, by rolling the die, the male screw is pressed.

The protrusion for forming the male screw is thin and high at the beginning,
The width gradually increases toward the end, and the groove between the ridges gradually narrows toward the end, and the rivet under the screw has the part pressed by the ridge entering the groove. It is molded, and the screw thread is gradually pressed in the shape to complete a predetermined screw screw.

Since the screw screw needs to have a tip, a lower part of the rolling die is provided with a forging kneading cut portion for forging the tip.

In the production of the screw screw using the rolling die as described above, in order to form the deep groove in the male screw,
A method in which a vertical knurling is provided in the middle of one rolling die and a V-shaped groove is formed in the thread of the male screw with this rollet, or another step is performed after the screw screw is pressed by the above rolling dies. Then, a method of forming a concave groove by making a notch in the thread of the male screw with a cutter can be considered.

[0010]

By the way, in the former method of forming a V-shaped groove by providing a vertical knurl in the middle of one rolling die, the groove is provided only in the thread. Although it was possible, when trying to form a groove deeper than the valley of the screw, the problem of having to deal with the transition of the meat allowance generated by forming the groove in the valley occurs, Therefore, unless this problem is solved, it is impossible to forge a screw screw having a deep groove deeper than the root of the screw.

Further, the latter method has a problem that a separate step for forming the concave groove is required, and the number of steps is increased, so that the manufacturing efficiency is lowered and the cost is increased.

Therefore, an object of the present invention is to solve the problem of shift of the meat allowance generated by forming the concave groove in the valley portion, and the male thread can be deformed without deforming the male thread in one step. We provide rolling dies that can form screws and deep grooves deeper than the valleys of male threads, and can manufacture screw screws with deep grooves at low cost, and methods for manufacturing deep grooved screws using this rolling die. To do.

[0013]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a rolling screw for producing a deep grooved screw having a male screw on the outer periphery of a shaft portion and a deep groove intersecting with the male screw. It is a forming die, and this rolling die consists of a combination of a fixed die and a moving die that face each other, and on each of the rolling faces that face each other of the fixed die and the moving die,
The ridges for forming deep and deep grooves are arranged at regular intervals over the entire surface, and the ridges are provided at regular intervals over the range from the middle of the rolling surface to the rear end and are lower than the above-mentioned ridges for deep groove formation. A projecting strip for forming an external thread having a small angle at a height is provided, and the projecting strip for forming the external thread is formed so that the width gradually widens toward the rear end, and is formed between the projecting strips. The valley groove is deep at the beginning, gradually becomes shallower toward the middle, and the depth from the middle to the end is the same.

The deep groove forming projections are, for example, about 20 ° with respect to the vertical direction of the rolling die over the entire surface of the rolling die at intervals such that two deep grooves are formed on the rivet under the screw. It is provided at an angle of.

The tip of the male thread forming protrusion has a height higher than the bottom surface between the deep groove forming protrusions and lower than the deep groove forming protrusion, and The same height condition is set from the middle to the end position of the manufacturing surface, and the valley groove formed between the adjacent male thread forming protrusions has a V-shaped cross section.

Further, the invention of the manufacturing method uses the rolling die described in the above invention, sandwiches the rivet under the screw between the fixed die and the moving die, and moves the moving die to move the circle of the rivet under the screw. First, by pushing a ridge for forming a deep groove into the outer periphery of the shaft portion, a plurality of vertical grooves having a sharp angle are formed, and at the same time, a meat allowance is transferred between the vertical grooves to form a bulged portion,
Next, while the deep groove forming ridges retain the vertical grooves, the bulging portion is pushed in by the male thread forming ridges and narrowed down to form a groove in the groove between the male thread forming ridges. This is a configuration in which the generation is shifted to form a male screw.

In the preceding stage of the fixed die and the moving die, the rib for forming the deep groove is pushed into the rivet under the screw to shift the meat allowance between the plurality of vertical grooves having sharp angles. By forming a bulge and fixing this bulge,
The bulging portion serves as a thickness for forming the male screw, and the ridge for forming the deep groove retains the vertical groove even during the process of forming the male screw on the bulging portion, so the vertical groove collapses. A male screw can be pressed into the bulge without pressing, and a screw screw with a deep groove can be made.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

The rolling die 11 of the present invention comprises a combination of a fixed die 12 and a moving die 13 which are arranged so as to face each other. Each of the rolling surfaces of the fixed die 12 and the moving die 13 which face each other is the same as that of the preceding stage. Both dies 12, 1 are formed in the deep groove forming zone A and the male screw forming zone B in the subsequent stage.
The pattern of the rolling surface 3 facing each other is symmetrical.

A ridge 1 for forming a deep groove having a sharp angle over the entire surface of the deep groove forming zone A and the male screw forming zone B.
4 are provided at regular intervals, and in the external thread forming zone B, a ridge 15 for forming an external thread having a lower height than the ridge 14 for forming the deep groove and having a gentle angle is formed for forming the deep groove. It is provided so as to be combined with the ridge 14.

The ridge 14 for forming the deep groove is shown in FIG. 5 with respect to the rivet 7 under the screw as shown in FIG.
As shown in (B), at an interval such that two deep grooves 6 are formed, the protrusion height is the same over the entire surfaces of both dies 12, 13, and an angle of about 20 ° with respect to the vertical direction of both dies 12, 13. And the flat bottom surface 16 formed between the ridges 14 has the same height over the entire surfaces of both dies 12, 13.

The male thread forming ridges 15 are provided in a state of being combined with the deep groove forming ridges 14 so that the male thread forming ridges 15 are arranged at regular intervals in the range starting from the middle of the rolling surface and reaching the rear end. The ridge 15 for forming the male screw has an inclination angle and an interval so that a continuous male screw 5 can be formed, and as shown in FIG. 2, its width d is directed toward the rear end. As shown in FIG. 3, the tip end surface formed into a flat shape that is gradually widened is higher than the bottom surface 16 between the deep groove forming projections 14, and the deep groove forming projections 14 are formed. Has a lower height than that of the rolling surface, and is set to the same height condition from the middle to the end position of the rolling surface. The width is wide at the beginning and narrows toward the end.

The valley groove 17 has a V-shaped cross section, and the depth thereof is deep at the beginning and gradually becomes shallower toward the middle, as shown in FIG. From the midpoint, the part of the same depth at the end is the final molded part of the male screw 5.

The fixed die 12 and the moving die 13
Has a substantially equal length in the external thread forming zone B in the rear stage,
The deep groove forming zone A of the moving die 13 may be set longer than the fixed die 12.

Next, a method of manufacturing a screw screw with a deep groove using the rolling die of the present invention will be described.

As shown in FIG. 4A, when the movable die 13 is in the retracted position with respect to the fixed die 12, FIG.
A rivet 7 under a screw as shown in (A) is supplied between the deep groove forming zones A, and the moving die 13 is moved in parallel with the fixed die 12 as shown in FIG. 4 (B). By pressing the ridge 14 for forming the deep groove against the outer circumference of the circular shaft portion of the rivet 7 under the screw between A, as shown in FIG.
As shown in (B), a plurality of vertical grooves 6 having a steep angle and a bulging portion 8 having a transitional margin are formed between the vertical grooves 6, and the bulging portion 8 is fixed.

Next, when the rivet 7 under the screw faces the male screw forming zone B as the moving die 13 moves, the male screw forming ridge 15 pushes in the bulging portion 8 and narrows it down. The external allowance is transferred to the troughs 17 between the thread-forming protrusions 15 to form the male screw 5.

The width d of the groove 17 is wide at first and narrows toward the terminal end, and the depth thereof is deep at the beginning and gradually decreases toward the middle as shown in FIG. Have the same depth. Therefore, the meat allowance that moves to the valley groove 17 by narrowing down the bulging portion 8 is initially deep and smoothly moves to the inside of the groove groove 17 by the wide portion, and this transition portion is shallow. The groove 17 is gradually narrowed to have a V-shaped cross section, and the final shape of the male screw 5 is finished at the same depth from the middle to the end.

When the male screw 5 is pressed in the male screw forming zone B, since the male thread forming zone B is provided with the ridge 14 for forming the deep groove, it is formed in the deep groove forming zone A at the preceding stage. The vertical groove 6 can retain its shape, and when the protrusion 15 for forming the male screw pushes the bulging portion 8 to narrow it down,
The migrating meat allowance does not escape into the vertical groove 6, so that the male screw 5 can be formed while keeping the vertical groove 6 in shape, and as shown in FIG. It is possible to manufacture the screw screw a having the vertical groove 6 deeper than the root diameter of the screw thread so as to intersect with the screw thread in one step.

Although not shown, the screw screw a is required to have a tip as in the conventional case, and therefore both dies 12, 13 are provided.
In the lower part of the, there is provided a pressed massaging section for pressing the tip.

[0031]

As described above, according to the present invention, the rolling surfaces of the fixed die and the moving die facing each other are
A ridge for forming a deep groove with a tight angle, which is provided over the entire surface at a constant interval, and a male with a lower angle and a lower angle than the ridge for forming a deep groove over the range from the middle of the rolling surface to the rear end. A ridge for forming a screw is provided so that the width of the ridge for forming a male screw is gradually widened toward the rear end. Therefore, a deep groove is formed first and the shape is retained until the end. As a result, a deep grooved screw can be manufactured with high accuracy without crushing the deep groove when the male screw is pressed.

Further, the screw screw with deep groove can be manufactured in one step, and the manufacturing cost can be reduced.

[Brief description of drawings]

1A is a front view showing a fixed die of a rolling die according to the present invention, FIG. 1B is a bottom view of the same, FIG. 1C is a left side view, and FIG. 1D is a right side view.

FIG. 2 is a perspective view showing a main structure of a fixed die.

FIG. 3 is a cross-sectional view of a fixed die.

FIG. 4A is a cross-sectional view of a threaded die supplied with a rivet under a screw, FIG. 4B is a cross-sectional view of a processed state of a rivet under a screw, and FIG. 4C is a processed state of a screw screw with a deep groove. Cross section of

5A is a front view of a rivet under a screw used for manufacturing a screw screw with a deep groove, FIG. 5B is a front view with a deep groove formed on the same, and FIG. 5C is a front view of a screw screw with a deep groove.

FIG. 6 is an enlarged cross-sectional view of a screw screw with a deep groove.

[Explanation of symbols]

a screw screw 1 head 2 tip 3 shafts 4 blank part 5 male screw 6 flutes 7 rivets under screws 8 bulge 11 Rolling dies 12 fixed die 13 Mobile dice 14 Protrusions for deep groove formation 15 Projection for forming male screw 16 flat bottom 17 Valley A deep groove formation zone B Male screw forming zone

Claims (2)

[Claims] 1. A rolling die for producing a deep grooved screw having a male thread on the outer periphery of a shaft portion and a deep groove intersecting with the male thread, and the rolling die moves with a fixed die facing each other. It consists of a combination of dies, and on each of the rolling surfaces of the fixed die and the moving die that face each other, a ridge for forming a deep deep groove with an angle, which is provided over the entire surface at a fixed interval, and from the middle to the rear end of the rolling surface. Is provided at a constant interval over the range reaching, and a protrusion for forming a male screw having a lower angle and a lower height than the protrusion for forming a deep groove is projected. , The width of the valley gradually widens toward the rear end, and the valley groove formed between the ridges is deep at the beginning and gradually becomes shallower toward the middle, and the depth between the middle and the end is the same. Rolling die for deep grooved screws. 2. The rolling die according to claim 1, wherein a rivet under the screw is sandwiched between a fixed die and a moving die, and by moving the moving die, the outer circumference of the circular shaft portion of the rivet,
First, by pushing in a ridge for forming a deep groove, a plurality of vertical grooves with sharp angles are formed, and at the same time, a bulge portion is formed by transferring a meat allowance between the vertical grooves, and then a ridge for forming a deep groove. While retaining the vertical groove, the bulging part is pushed in by the ridges for forming male threads to narrow it down, and the meat allowance is transferred to the troughs between the ridges for forming male threads to form male threads. Method for manufacturing deep grooved screw.