JPH0738735U - Screw connection structure - Google Patents

Abstract

(57) [Abstract] [Purpose] To be able to increase the screw connection strength of the joint. In a screw connection structure in which a male screw 22 of a male screw forming member 21 and a female screw 23 of a female screw forming member 19 are screwed together, a pitch difference is provided between the female screw and the male screw.
The female screw is formed with a taper in the diameter reducing direction, or the male screw is formed with a taper in the diameter expanding direction.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a screw connection structure, for example, a screw connection structure applied to a connection part of a handle of a cleaning tool.

[0002]

[Prior art]

 There are some types of cleaning tools such as mops that can be assembled in consideration of the convenience of transportation from the factory to the store or transportation from the store to the home. For example, in the brush with handle described in Japanese Utility Model Publication No. 3-35142, it is proposed that the handle is composed of a plurality of pipes, and the tip of the handle is detachably inserted into the grip of the brush or the like. (First conventional example). Further, Japanese Utility Model Laid-Open No. 59-195210 proposes that a large-diameter pipe and a small-diameter pipe are inserted with a wedge to connect both pipes (second conventional example).

[0003]

[Problems to be solved by the device]

 However, in the first conventional example, since the handle and the grip are connected by inserting the tip of the handle into the grip, the handle may come off from the grip when the brush with handle is used.

Further, it is conceivable that the second conventional example is applied to the joint between the handle and the grip, or the joint between a plurality of pipes forming the handle, and the wedge is used for joining. Furthermore, it is conceivable to use a screw connection instead of the wedge. However, in these cases, it is considered that the impact during cleaning causes the wedge to move or the screw to loosen, resulting in insufficient connection at the joint.

The present invention has been made in consideration of the above circumstances, and an object thereof is to provide a screw connection structure capable of increasing the screw connection strength of a connection portion.

[0006]

According to a first aspect of the invention, in a screw coupling structure in which a male screw of a male screw forming member and a female screw of a female screw forming member are screwed together, there is a pitch difference between the male screw and the female screw. The female screw is provided with a taper in the diameter reducing direction, or the male screw is formed with a taper in the diameter expanding direction.

Further, the invention according to claim 2 is such that at least one of the male screw forming member and the female screw forming member of the invention according to claim 1 is formed of resin.

[0008]

[Action]

 Therefore, according to the screw coupling structure of the first aspect, the pitch difference is provided between the male screw and the female screw, and therefore, when the male screw and the female screw are screwed, the axial compression force acts on the respective threads and valleys. To do. In addition, since the internal thread has a taper in the radial direction or the external thread has a taper in the radial direction, when the male and female threads are screwed together, the radial tightening force between the threads and valleys Works. These axial compressive force and radial tightening force increase the tightening effect of the male screw and the female screw and prevent them from loosening, thereby increasing the screw joint strength of the joint portion.

Further, according to the screw coupling structure of the second aspect of the invention, at least one of the male screw forming member and the female screw forming member is resin-molded, and since this resin has high elastic deformation performance, Since the pitch difference at which the female screw can be screwed is large, a high degree of thread processing accuracy is not required. Therefore, the screw processing cost can be reduced.

[0010]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of a mop showing a handle to which an embodiment of the screw coupling structure according to the present invention is applied, together with the main body of the mop. 2 (A) is a cross-sectional view showing a handle element that constitutes the handle of FIG. 1, and FIG. 2 (B) is a cross-sectional view taken along line IIB-IIB of FIG. 1 (A). FIG. 3 is a sectional view showing a connecting portion of the handle element. 4A shows the male screw forming member of FIG. 3, FIG. 4A being a front view thereof, and FIG. 4B being a left side view thereof. FIG. 5 shows the male screw fixing member and the female screw forming member of FIG. 3, (A) is a sectional view thereof, (B) is a left side view thereof, (C) is a plan view thereof, and (D) is a perspective view thereof. is there. FIG. 6 is an enlarged cross-sectional view of the main part of FIG.

In the mop 10 shown in FIG. 1, a non-woven cloth sheet 13 for collecting dirt is attached to a bottom surface 12 of a mop body 11, and a handle 15 is attached to an upper portion of the mop body 15 via a joint 14. Consists of The handle 15 is formed by screwing a plurality of handle elements 16, in this embodiment, a handle first element 16A, a handle second element 16B, a handle third element 16C and a handle fourth element 16D. One element 16A is screwed to the joint 14. Further, the handle portion 17 is provided on the handle fourth element 14D.

Each handle element 16 has the same structure. For example, in the handle first element 16A, as shown in FIG. 2A, a female thread forming member 19 and a male thread fixing member 20 are attached to both ends of a pipe 18, respectively. A male screw forming member 21 is screwed onto the male screw fixing member 20. The pipe 18 is made of, for example, aluminum or aluminum alloy. The female screw forming member 19 and the male screw fixing member 20 are formed in the same shape and the same size.

As shown in FIG. 4, the male screw forming member 21 has a cylindrical shape and has a male screw 22 formed on the outer peripheral surface thereof, and a cross-shaped groove 22 A is formed on one end side. A plus driver or the like can be fitted into the cross groove 22A. The male screw forming member 21 is made of iron, for example, carbon steel for cold rolling.

As shown in FIG. 5, the female screw forming member 19 and the male screw fixing member 20 have a substantially cylindrical shape, and a female screw 23 is formed on the tip side thereof, and the male screw 22 of the male screw forming member 21 is screwed into the female screw 23. Is possible. The female screw forming member 19 and the male screw fixing member 20 are made of a synthetic resin such as 6-6 nylon, and a hole 24 for preventing shrinkage at the time of molding is formed on the base end side in the axial direction. The holes 24 ensure the radial dimension of the outer diameter portion 25 during molding.

A plurality of (for example, six) guide grooves 26 are formed in the outer diameter portion 25 of the female screw forming member 19 and the male screw fixing member 20 so as to extend in the circumferential direction. Further, a triangular introduction surface 27 is formed on the base end sides of the female screw forming member 19 and the male screw fixing member 20 so as to be lower than the outer diameter portion 25 and at the same level as the guide groove 26. The apex of the introduction surface 27 is connected to the guide groove 26, and the oblique side of the introduction surface 27 serves as a step with respect to the outer diameter portion 25 and functions as an introduction guide 28.

On the other hand, a pipe protrusion 29 is formed on the inner peripheral surface of the pipe 18 shown in FIG. 2, and the guide surfaces 26 of the female screw forming member 19 and the male screw fixing member 20 are fitted into the pipe protrusion 29. To meet. When inserting the female screw forming member 19 and the male screw fixing member 20 into the end portion of the pipe 18, the pipe protrusion 29 of the pipe 18 contacts the introducing guide 28 from the introducing surface 27, and the female screw forming member 19 and the male screw fixing member 20 are axial. It rotates around and is guided by the guide groove 26, and is fitted into the guide groove 26. By fitting the pipe protrusion portion 29 and the guide groove 26, the female screw forming member 19 and the male screw fixing member 20 are positioned with respect to the circumferential direction of the pipe 18 and a detent in the same direction is achieved. After that, caulking 30 is performed from the outer peripheral side of the pipe 18 to securely fix the female screw forming member 19 and the male screw fixing member 20 to the pipe 18.

As described above, the female screw forming member 19 and the male screw fixing member 20 are fitted to the ends of the handle first element 16A, the handle second element 16B, the handle third element 16C and the handle fourth element 16D. After that (FIG. 2 shows the case of the handle first element 16), the male screw 22 of the male screw forming member 21 is screwed into the female screw 23 of the male screw fixing member 20 to fix the male screw forming member 21. At this time, as shown in FIG. 3, the male screw forming member 21 is screwed into the female screw 23 of the male screw fixing member 20 to the depth of the dimension A.

In this way, the male screw forming member 21 fixed to the male screw fixing member 20 is screwed with the female screw 23 of the female screw forming member 19 of the handle second element 16B having the same structure, and the handle first element 16A. The handle second element 16B is screwed to the shaft. At this time, the male screw forming member 21 of the first handle element 16A is screwed to the depth B (A> B) of the female screw forming member 19 of the second handle element 16B.

Similarly, the male thread forming member 21 of the second handle element 16B is screwed with the female thread forming member 19 of the third handle element 16C, and the third handle element 16C is screwed to the second handle element 16B. To be done. Further, the male thread forming member 21 of the handle third element 16C is screwed into the female thread forming member 19 of the handle fourth element 16D, and the handle fourth element 16D is screwed to the handle third element 16C.

A pitch difference is provided between the male screw 22 of the male screw forming member 21 and the female screw 23 of the female screw forming member 19 and the male screw fixing member 20. For example, one pitch of the male screw 22 or the female screw 23 is set to about 1.50 mm, and the other pitch is set to about 1.48 mm.

Further, as shown in FIG. 6, the female screw 23 is formed with a taper T ₁ in the diameter reducing direction. The taper T ₁ is formed in a thread, starts from the tip surface 31 of the female screw forming member 19 and the male screw fixing member 20 at a position of dimension L ₁ , and is formed in a deeper range than that. Therefore, the inner diameter difference t of the thread between the position of the dimension L ₁ and the deepest portion is set to about 0.3 mm.

According to the above embodiment, since the male screw 22 of the male screw forming member 21 and the female screw 23 of the female screw forming member 19 and the female screw fixing member 20 are provided with a pitch difference, the male screw 22 and the female screw 23 are screwed together. At times, an axial compressive force acts between each thread and thread trough. Further, since the taper T ₁ in the diameter reducing direction is formed on the thread of the female screw 23, when the male screw 22 and the female screw 23 are screwed together, a radial tightening force acts between the respective threads and valleys. Due to the axial compression force and the radial tightening force, the tightening effect of the male screw 22 and the female screw 23 is increased, and it becomes difficult for the male screw 22 and the female screw 23 to loosen, and the screw joint strength of the joint portion can be increased.

Further, since the taper T ₁ of the female screw 23 is provided after the position of the dimension L ₁ from the tip surface 31 of the female screw forming member 19 and the male screw fixing member 20, the initial screwing of the male screw 22 and the female screw 23 is performed. The male screw 22 can also be easily screwed into the taper T ₁ region of the female screw 23 due to its inertia. Therefore, the male screw 22 can be easily tightened to the female screw 23.

Further, the female screw forming member 19 and the male screw fixing member 20 are resin-molded, and since this resin has a high elastic deformation performance, the pitch difference in which the male screw 22 and the female female 23 can be screwed becomes large, and a high-grade screw is formed. Machining accuracy is not required. Therefore, the screw processing cost can be reduced.

Further, since the male screw forming member 21 is screwed deeper into the male screw fixing member 20 than in the female screw forming member 19, for example, the handle second element 16B is removed from the handle first element 16A. When the handle second element 16B is rotated with respect to the handle first element 16A, the male screw forming member 21 is secured in a screwed state with respect to the male screw fixing member 20, and is only screwed with the female screw 23 of the female screw forming member 19. Can be canceled.

Further, since the introduction surface 29 and the introduction guide 28 are formed on the female thread forming member 19 and the male thread fixing member 20, the pipe protrusion 29 of the pipe 18 of the handle element 16 is fixed to the female thread forming member 19 and the male thread. It becomes easier to fit the guide groove 26 of the fixing member 20, and the female screw forming member 19 and the male screw fixing member 20 can be easily attached into the pipe 18.

Further, since the female screw forming member 19 and the male screw fixing member 20 are attached to the pipe 18 by fitting the guide groove 26 and the pipe ridge portion 29, the female screw forming member 19 and the pipe of the male screw fixing member 20 are attached. The rotation stop for 18 is achieved, and the circumferential stop (fixing) position of the female screw 23 in the female screw forming member 19 and the male screw fixing member 20 is made constant. For example, the handle first element 16A is screwed to the handle second element 16B. When this is done, the caulking 30 of both handle elements 16A, 16B can be aligned in a straight line, improving the aesthetics.

FIG. 7 is an enlarged sectional view of an essential part showing a modified example of the female screw forming member and the male screw fixing member. The internal thread 32 of the internal thread forming member and the external thread fixing member 20 has a taper T ₂ Are formed in the thread roots of the female screw 32.

FIG. 8 is an enlarged sectional view of an essential part showing a modified example of the male screw forming member. In the above-mentioned embodiments and modified examples, the tapers T ₁ and T ₂ are formed on the internal threads 23 and 32 of the internal thread forming member 19 and the external thread fixing member 20, respectively. However, as shown in FIG. Only the male screw 34 of the member 33 may be formed with the taper T _{3 in the} radial direction. The taper T ₃ is formed within the range of the dimension L ₂ from the tip surface of the male screw forming member 33.

It should be noted that, in the above-mentioned embodiment and both modified examples, the female screw forming member 19 and the male screw fixing member 20 are described as resin molded, but the male screw forming members 21, 33 are resin molded and the female screw forming member 19 is formed. The male screw fixing member 20 may be made of iron, or the female screw forming member 19, the male screw fixing member 20, and the male screw forming members 21 and 33 may be resin-molded.

[0031]

[Effect of device]

 As described above, according to the screw connection structure of the present invention, the screw connection strength of the connection portion can be increased.

[Brief description of drawings]

FIG. 1 is a perspective view of a mop showing, together with a mop body, a handle to which an embodiment of a screw coupling structure according to the present invention is applied.

2 (A) is a cross-sectional view showing a handle element that constitutes the handle of FIG. 1, and FIG. 2 (B) is a view of II of FIG. 1 (A).
It is sectional drawing which follows the B-IIB line.

FIG. 3 is a sectional view showing a connecting portion of a handle element.

FIG. 4 (A) shows the male screw forming member of FIG.
(A) is the front view, (B) is the left side view.

5 shows the male screw fixing member and the female screw forming member of FIG. 3, (A) is a sectional view thereof, (B) is a left side view thereof, (C) is a plan view thereof, and (D) is a sectional view thereof. It is the perspective view.

6 is an enlarged cross-sectional view of a main part of FIG. 5 (A).

FIG. 7 is an enlarged sectional view of an essential part showing a modified example of the female screw forming member and the male screw fixing member.

FIG. 8 is an enlarged sectional view of an essential part showing a modified example of the male screw forming member.

[Explanation of symbols]

10 Mop 11 Mop handle 16 Handle element 18 Pipe 19 Female screw forming member 20 Male screw fixing member 21 Male screw forming member 22 Male screw 23 Female screw T ₁ Taper of female screw

Claims (2)

[Scope of utility model registration request] 1. In a screw coupling structure in which a male screw of a male screw forming member and a female screw of a female screw forming member are screwed together, a pitch difference is provided between the male screw and the female screw, and the female screw has a taper in a diameter reducing direction. Alternatively, a screw coupling structure in which the male screw is formed with a taper in a radial expansion direction. 2. The screw coupling structure according to claim 1, wherein at least one of the male screw forming member and the female screw forming member is molded of resin.