JPH0550138U - Fastener - Google Patents

Abstract

(57) [Summary] [Purpose] The protrusion formed on the upper surface of the male thread is
The female screw rushes into the notch formed in the screw groove of the female screw, the female screw locks, the female screw turns in a direction that naturally relaxes and weakens the fastening force, and the female screw does not fall from the male screw. An object of the present invention is to provide a fastener that can maintain a constant fastening force. [Structure] A male screw 1 having protrusions 1d formed in the same direction on the upper surface 1c ″ of each screw thread 1c of a screw shaft 1b protruding from the lower surface of a wide-diameter head 1a in plan view, and each of the male screw 1 The thread gap A of each screw groove screw groove 2a corresponding to the screw thread 1c is formed wide according to the height of the protrusion 1d of the screw thread 1c, and the same direction in plan view in each screw groove 2a is the shape of the protrusion 1d. And a female screw 2 which is cut out in accordance with the above.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a fastener that can eliminate loosening of a female screw that occurs when a female screw is fastened to a male screw.

[0002]

[Prior art]

 The fastener in the prior art, in which a male screw, a female screw, and a spring washer are combined, has flat spiral surfaces formed on the upper and lower surfaces of the screw thread formed on the outer peripheral surface of the screw shaft of the male screw. The screw groove formed on the inner peripheral surface of the female screw that is screwed to the male screw is formed by a flat spiral surface that is approximately equal to the pitch of the male screw. Fit a spring washer to push the screw shaft into multiple clamped members, etc., and tighten the female screw to the end of the screw shaft protruding from the back side of the clamped member's insertion surface to tighten the male screw. The multiple members that are sandwiched between the female screw and the female screw are securely fastened.The female screw that has been tightened once loosens against the compression repulsive force of the spring washer, clamped member, etc. Fruit reduction or female screw Not a few either that or fall out.

Conventionally, in order to deal with such loosening of the female screw, another female screw is screwed to the fastened female screw end so as to reduce the looseness by the plurality of female screws, or the female screw. A communication hole is provided in each of the male screw and the male screw, and a cotter pin is inserted into the communication hole to prevent rotation.

[0004]

[Problems to be solved by the device]

 However, in order to screw two female screws to the male screw, the male screw is long enough to screw at least two female screws, and further requires two female screws. For example, the tightening work requires time and labor, and the fasteners are long, so the tightened parts are unsightly. Further, the work of connecting the split pin to the male screw and the female screw is also troublesome and time-consuming.

The present invention has been proposed in view of the above circumstances, and a male screw having protrusions formed in the same direction on the upper surface of each screw in a plan view and a pitch of a screw groove are protrusions of the screw. It is formed widely according to the height of each screw groove, and each screw groove is formed with a female screw that is cut out in the same direction in plan view according to the shape of the protrusion, and the direction in which the female screw loosens naturally The purpose of this is to maintain a constant fastening force at all times without weakening the fastening force or turning the female screw out of the male screw.

[0006]

[Means for Solving the Problems]

 This invention proposed to solve the above problems is a male screw having protrusions formed at the same direction in plan view on the upper surface of each screw thread of the screw shaft protruding to the lower surface of the wide diameter head, The space between the screw grooves corresponding to the screw threads of the male screw is formed widely according to the height of the protrusion of the screw thread, and the same direction in plan view of each screw groove is adjusted to the shape of the protrusion. It is characterized by being combined with a notched female screw.

[0007]

[Action]

 When the male screw is inserted into the spring washer and the female screw is screwed, and the male screw (or female screw) is rotated in the tightening direction in this state, the male screw (or female screw) becomes the screw thread of the male screw. The lower surface of the female screw and the lower surface of the screw groove of the female screw are in contact with each other, and the upper end of the protrusion formed on the upper surface of the screw thread of the male screw is in contact with the upper surface of the screw groove of the female screw. When the male screw (or female screw) is fastened in this way, the male screw is formed in the thread groove of the female screw due to the compression repulsive force of the spring washer interposed between the male screw and the female screw. When the female screw is pressed downwards, the upper surface of the male screw thread and the lower surface of the female screw groove are in contact with each other, and this state is maintained at all times. It will not loosen to loosen the fastening pressure or fall off the male screw and fall.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of the fastener of this invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is an overall side view including a partial cross-section showing an embodiment of a male screw and a female screw constituting a fastening tool of the present invention, FIG. 2 is a partial front view of the male screw, and FIG. 3 is an X in FIG. -X sectional view, FIG. 4 is a plan view of the female screw, and FIG. 5 is a plan sectional view of the same. As shown in these figures, the fastener of the present invention is a combination of a male screw and a female screw, and a spring washer is used for other fastening.

As shown in FIGS. 1 to 3, the male screw 1 has a wide-diameter head portion 1a formed on an upper portion thereof, and a screw shaft 1b projects from a lower surface of the head portion 1a, and the screw shaft 1b. A single thread 1c is formed on the outer peripheral surface of the. The flank angle α of the lower surface 1c ′ of each screw thread 1c is formed to be 30 ° in the case of a general metric screw, while the upper surface 1c ″ of the screw thread 1c is located at the same position in plan view. At this one place, the entire surface of the other upper surface 1c ″ is formed low, leaving a portion from the valley 1e of the upper surface 1c ″ of each screw thread 1c to the vicinity of the tip, and the remaining portion becomes the protrusion 1d. .

The male screw 1 shown in this drawing is formed in a so-called trapezoidal screw shape in which a surface is formed on the outer peripheral end of the screw thread 1c, but the outer peripheral end may be an acute angle. . Further, in this invention, since the diameter of the screw thread 1c of the male screw 1 is wide, when a spring washer 3 described later is fitted, it is stably positioned below the head portion 1a. A wide-diameter seat 1f is formed on the lower surface of the head 1a so that it can be moved. The spring washer 3 may be attached in advance below the head portion 1a of the male screw 1.

As shown in FIGS. 1 and 4, the female screw 2 is formed with a screw groove 2 a corresponding to the screw shaft 1 b of the male screw 1, and the groove gap A of the screw groove 2 a is The screw thread 1c including the protrusion 1d is inserted into the screw groove 2a, and the upper end of the protrusion 1d is formed widely so as to be in contact with the upper surface 2a 'of the screw groove 2a. Further, the flank angle θ of the upper surface 2a ′ of the screw groove 2a is made to coincide with the flank angle η of the upper surface 1c ″ of the screw thread 1c of the male screw 1. Further, the same position as the female screw 2 in plan view is provided. The notches 2c ... which match the shape of the projection 1d are formed in the four screw grooves 2a .. which are evenly spaced apart from each other, and the upper surface 2a 'of the screw groove 2a is formed by a die described later. In addition to being formed, as shown in FIG. 5, a hatched portion f above the screw groove 2a The spring washer 3 serves to maintain the fastening force and prevent the female screw 2 from coming off when the female screw 2 is screwed and fastened to the male screw 1. A wide diameter screw is used according to the diameter of the screw thread 1c of the male screw 1, and the spring washer 3 is formed by an independent C-shaped spring, or a spring washer of another shape, or the male screw. A male washer-integrated spring washer fixed to the lower surface of the head 1a of FIG.

6 to 8 are front partial cross-sectional views showing a screwed state of the fastener of the present invention, and FIG. 9 is a plan view of a female screw screwed to a male screw, and FIGS. 9, the same parts as those in FIGS. 1 to 5 are designated by the same reference numerals. First, as shown in FIG. 6, the spring washer 3 is fitted into the male screw 1, and then the female screw 2 is screwed from the tip of the screw shaft 1b of the male screw 1 to form the male screw 1 (or the female screw). When the screw 2) is turned in the tightening direction, the male screw 1 (or the female screw 2) is brought into contact with the lower surface of the screw thread 1c of the male screw 1 and the lower surface of the screw groove 2a of the female screw 2, and the male screw 1 The upper end of the projection 1d formed so as to project on the upper surface 1c ″ of the screw thread 1c of No. 1 advances while being in contact with the upper surface 2a ′ of the screw groove 2a of the female screw 2.

Subsequently, as shown in FIG. 7, when the male screw 1 (or female screw 2) is continuously rotated, the spring washer 3 interposed between the male screw 1 and the female screw 2 is pressed in the compression direction. For this reason, the upper end of the protrusion 1d is gradually abutted against the upper surface 2a 'of the screw groove 2a, and the screw is advanced.

Further, as shown in FIGS. 8 and 9, when the male screw 1 (or the female screw 2) is continuously rotated and strongly tightened until the spring washer 3 becomes flat, the female screw 2 of the female screw 2 is close to the end of the tightening. The protrusion 1d of the male screw 1 projects into the notch 2c in the vicinity of the screw groove 2a, and the compression repulsive force of the spring washer 3 causes the upper surface 1c ″ of the screw thread 1c of the male screw 1 to be a female screw. The female screw 2 comes into contact with the lower surface 1c ′ of the two screw grooves 2a, and the female screw 2 is locked with a gap between the lower surface 1c ′ of the male screw 1 and the upper surface 2a ′ of the female screw 2. If the notch 2c of the protrusion 1d is not located near the end of tightening the male screw 1 (or the female screw 2), the male screw 1 (or the female screw 2) is returned to the original position, and the screw groove near The protrusion 1d may be inserted into 2a.

FIG. 10A is a plan view of a die 5 for molding the male screw 1 of the fastener of the present invention, FIG. 10B is a side view of the same, and FIG. 11 is a diagram showing an example of using the die. As shown in FIGS. 10A and 10B, recesses 5b ... Corresponding to the protrusions 1d are formed at regular intervals on the upper slope 5a of the die 5 at regular intervals. As shown in FIG. 1, when the male screw thread is formed, the dice 5 and 5 are moved in opposite directions while the male screw 1 is sandwiched between the dies 5 and 5 arranged in parallel. When the screw shaft 1b is rolled, a male screw having the projection formed on the outer peripheral surface of the screw shaft 1b is formed.

[0016]

[Effect of the device]

 According to the present invention described above, when the spring washer is fitted to the male screw and the female screw is fastened, the projection formed on the upper surface of the screw thread of the male screw by the compression repulsive force of the spring washer causes Since the female screw engages with the notch formed in the screw groove and the female screw locks, the female screw does not turn around in the direction that it loosens naturally to weaken the fastening force and the female screw does not drop from the male screw. It is possible to maintain the fastening force of. Moreover, unlike the conventional method, there is no need for a female thread for preventing loosening or a split pin that is used to eliminate loosening or disengagement of the female thread, and simply tightening the female screw can be used for fastening and locking. It will also be convenient.

[Brief description of drawings]

FIG. 1 is an overall side view including a partial cross-section showing an embodiment of a male screw and a female screw constituting a fastener.

FIG. 2 is a partial front view of a male screw.

FIG. 3 is a sectional view taken along line XX in FIG.

FIG. 4 is a plan view of a female screw.

FIG. 5 is the same plan sectional view.

FIG. 6 is a front partial cross-sectional view showing a screwed state of the fastener.

FIG. 7 is a front partial cross-sectional view showing a screwed state of the fastener.

FIG. 8 is a partial front sectional view showing a screwed state of the fastener.

FIG. 9 is a plan view of a female screw screwed on a male screw.

FIG. 10A is a plan view of a die for molding a male screw,
(B) is also a side view.

FIG. 11 is a side view showing a usage example of a die.

[Explanation of symbols]

 A groove 1 male screw 1a head 1b screw shaft 1c screw thread 1c 'lower surface of screw thread 1c 1c "upper surface of screw thread 1c 1d protrusion 1e valley 2 female screw 2a screw groove 2a' upper surface of screw groove 2a 2a" screw groove Lower surface of 2a 2c Notch 3 Spring washer

Claims (1)

[Scope of utility model registration request] 1. A male screw having a projection formed on the upper surface of each screw thread of a screw shaft projecting from the lower surface of a wide-diameter head in the same direction in plan view, and each screw corresponding to each screw thread of the male screw. A wide space is formed between the grooves according to the height of the protrusion of the screw thread, and a combination of a female screw formed by notching the screw groove at the same direction in plan view in each screw groove is formed according to the shape of the protrusion. A fastener characterized by the following.