Compressive spring

Abstract

To provide a compressive spring capable of preventing elastic force from decreasing due to plastic deformation caused by telescopic motion.SOLUTION: A compression spring 1 has a unit structure 2 having: a first annular member 2a and a second annular member 2b spaced apart from each other in an axial direction along a central axis O; and a plurality of spring members 2c that are arranged so that their phases deviate in a circumferential direction around the central axis O, and each extend linearly from a first end connected to the first annular member 2a to a second end connected to the second annular member 2b at a position circumferentially deviating from the first end along a predetermined path P before elastic deformation while continuously changing a cross-sectional area perpendicular to the predetermined path P, where each spring member 2c of the unit structure 2 satisfies the following condition A before elastic deformation. Condition A: Sa>Sb>Sc, and Se>Sd>Sc.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to compression springs. [Background technology]

[0002] A compression spring having a unit structure is known that has a first annular member and a second annular member that are spaced apart from each other in the axial direction along the central axis, and a plurality of spring members that are arranged with a phase shift in the circumferential direction around the central axis, each extending linearly along a predetermined path from a first end connected to the first annular member to a second end connected to the second annular member at a position circumferentially shifted from the first end (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2022-102886 Summary of the Invention [Problem to be solved by the invention]

[0004] It is preferable that the above-mentioned compression spring is resistant to a decrease in elastic force due to plastic deformation accompanying expansion and contraction operations.

[0005] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a compression spring which is less susceptible to a decrease in elastic force due to plastic deformation accompanying expansion and contraction operations. [Means for solving the problem]

[0006] One aspect of the present invention is as follows.

[0007] [1] a unit structure including a first annular member and the second annular member spaced apart from each other in an axial direction along a central axis line, and a plurality of spring members arranged with a phase difference in a circumferential direction around the central axis line, each of which extends linearly from a first end connected to the first annular member to a second end connected to the second annular member at a position shifted in the circumferential direction from the first end, while continuously changing a cross-sectional area perpendicular to the predetermined path in a state before elastic deformation; Each of the spring members of the unit structure is a compression spring that satisfies the following condition A in a state before elastic deformation. Condition A: Sa>Sb>Sc, and Se>Sd>Sc However, the spring member is divided into four sections of equal length along the specified path from point A located at the first end to point B, from point B to point C, from point C to point D, and from point D to point E located at the second end, and the cross-sectional area of ​​point A is Sa, the cross-sectional area of ​​point B is Sb, the cross-sectional area of ​​point C is Sc, the cross-sectional area of ​​point D is Sd, and the cross-sectional area of ​​point E is Se.

[0008] [2] The compression spring according to [1], wherein each of the spring members satisfies the following condition B in a state before the elastic deformation: Condition B: 0.4≦Rca≦0.75 and 0.4≦Rce≦0.75 where Sc / Sa=Rca, Sc / Se=Rce

[0009] [3] The compression spring according to [1] or [2], wherein each of the spring members satisfies the following condition C in a state before the elastic deformation. Condition C: 40°≦θ≦60° In this regard, when viewed in a developed view, the acute angle that a straight line connecting the center of the first end and the center of the second end forms with respect to the circumferential direction is defined as θ.

[0010] [4] Each of the spring members extends within a region where the predetermined path is located between the two annular members along the axial direction from the first end to the second end in a state before elastic deformation, and an inner peripheral radius, which is a radius orthogonal to the central axis at the inner peripheral edge of the spring member when viewed in the axial direction, continuously changes and satisfies the following condition D. The compression spring according to any one of [1] to [3]. Condition D: Ria < Rib < Ric, and Rie < Rid < Ric However, let the inner peripheral radius at point A be Ria, the inner peripheral radius at point B be Rib, the inner peripheral radius at point C be Ric, the inner peripheral radius at point D be Rid, and the inner peripheral radius at point E be Rie.

[0011] [5] The compression spring according to any one of [1] to [4], and a cylinder, a piston, an operating member that discharges fluid through the inside of the cylinder by operating the piston against the elastic force of the compression spring. A discharge device having the same.

Advantages of the Invention

[0012] According to the present invention, it is possible to provide a compression spring in which a decrease in elastic force due to plastic deformation accompanying expansion and contraction operation is less likely to occur.

Brief Description of the Drawings

[0013] [Figure 1] It is a front view of the compression spring of one embodiment of the present invention. [Diagram 2] It is a top view of the compression spring shown in FIG. 1. [Diagram 3] It is a right side view of the compression spring shown in FIG. 1. [Figure 4] It is a perspective view of the compression spring shown in FIG. 1. [Diagram 5] It is a developed view of the spring member shown in FIG. 1. [Figure 6] It is a cross-sectional view showing an example of a discharge container having the compression spring shown in FIG. 1 in a state before a discharge operation. [Figure 7] 2 is a cross-sectional view showing an example of a dispensing container having the compression spring shown in FIG. 1 in a state during a dispensing operation. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0015] As shown in Figures 1 to 5, in one embodiment of the present invention, a compression spring 1 has a unit structure 2 including a first annular member 2a and a second annular member 2b that are spaced apart from each other in an axial direction along a central axis O, and a plurality of spring members 2c that are arranged with a phase shift in a circumferential direction around the central axis O and each extend linearly from a first end connected to the first annular member 2a to a second end connected to the second annular member 2b at a position circumferentially shifted from the first end, along a predetermined path P before elastic deformation, while continuously changing a cross-sectional area perpendicular to the predetermined path P, and each spring member 2c of the unit structure 2 satisfies the following condition A before elastic deformation. Condition A: Sa>Sb>Sc, and Se>Sd>Sc However, the spring member 2c is divided into four sections of equal length along the predetermined path P, namely, from point A a located at the first end to point B b, from point B b to point C c, from point C c to point D d, and from point D d to point E e located at the second end, and the cross-sectional area of ​​point A a is Sa, the cross-sectional area of ​​point B b is Sb, the cross-sectional area of ​​point C c is Sc, the cross-sectional area of ​​point D d is Sd, and the cross-sectional area of ​​point E e is Se.

[0016] In a compression spring 1 having a unit structure 2 including a first annular member 2a and a second annular member 2b spaced apart from each other in the axial direction, and a plurality of spring members 2c arranged with a phase shift in the circumferential direction and linearly extending along a predetermined path P from a first end connected to the first annular member 2a to a second end connected to the second annular member 2b at a position shifted in the circumferential direction from the first end, stress is generally likely to concentrate on the first and second ends of the spring members 2c during expansion and contraction, and as a result, elastic force is likely to decrease due to plastic deformation at the first and second ends. However, according to the above configuration regarding condition A, stress concentration on the first and second ends can be suppressed by dispersing stress toward the midpoint between the first and second ends. Therefore, a compression spring 1 in which elastic force is less likely to decrease due to plastic deformation accompanying expansion and contraction can be realized. The decrease in elastic force due to plastic deformation at the first end and the second end can be classified into two types: (1) plastic deformation over time due to continued compression, and (2) plastic deformation due to repeated expansion and contraction. (1) occurs, for example, when the compression spring 1 is provided in a pump, due to an initial load that is set to keep the compression spring 1 in a slightly compressed state in order to ensure that the operating part is returned to a specified position, and the elastic force for holding the operating part in the specified position is lost. (2) occurs, for example, when the compression spring 1 is provided in a pump, due to repeated operation of the operating part, and the elastic force for returning the operating part to the specified position is lost.

[0017] The cross-sectional area between point A a and point B b is maximum at point A a, the cross-sectional area between point B b and point C c is maximum at point B b, the cross-sectional area between point C c and point D d is maximum at point D d, and the cross-sectional area between point D d and point E e is maximum at point E e. With the above configuration, stress concentration on the first end and the second end during extension and contraction can be further suppressed.

[0018] The cross-sectional area of ​​each spring member 2c before elastic deformation changes continuously from point A a to point E e. According to the above configuration, stress concentration on the first end and the second end during expansion and contraction can be further suppressed.

[0019] The cross-sectional area of ​​each spring member 2c, before elastic deformation, decreases continuously from point A a to point B b, and also decreases continuously from point E e to point D d. According to the above configuration, stress concentration on the first end and the second end during the expansion and contraction operation can be further suppressed.

[0020] The cross-sectional area of ​​each spring member 2c, before elastic deformation, continuously decreases from point B b to point C c and continuously decreases from point D d to point C c. With the above configuration, stress concentration on the first end and the second end during the extension and contraction operation can be further suppressed.

[0021] Each spring member 2c satisfies the following condition B before elastic deformation. Condition B: 0.4≦Rca≦0.75 and 0.4≦Rce≦0.75 Here, Sc / Sa=Rca and Sc / Se=Rce. According to the above configuration, stress concentration at the first end and the second end can be further suppressed during the expansion and contraction operation. If the ratio is less than 0.4, stress is likely to concentrate at the midpoint between the first end and the second end. If the ratio exceeds 0.75, it becomes difficult to obtain the effect of suppressing stress concentration at the first end and the second end.

[0022] Each spring member 2c satisfies the following condition C before elastic deformation. Condition C: 40°≦θ≦60° However, when viewed in a developed view, the acute angle that a straight line connecting the center of the first end and the center of the second end forms with the circumferential direction is defined as θ. According to the above configuration, stress concentration at the first end and the second end during the extension / contraction operation can be further suppressed. If the angle is less than 40°, it becomes difficult to obtain the extension / contraction stroke amount and repulsive force. If the angle exceeds 60°, the deformation amount of the spring member 2c during the extension / contraction operation becomes excessive, making it difficult to obtain the effect of suppressing stress concentration at the first end and the second end.

[0023] Before elastic deformation, each spring member 2c has a predetermined path P extending along the axial direction from the first end to the second end within a region located between the two annular members, and the inner peripheral radius, which is the radius perpendicular to the central axis O at the inner peripheral edge of the spring member 2c when viewed in the axial direction, changes continuously, and satisfies the following condition D. Condition D: Ria < Rib < Ric and Rie < Rid < Ric However, let the inner peripheral radius of point A a be Ria, the inner peripheral radius of point B b be Rib, the inner peripheral radius of point C c be Ric, the inner peripheral radius of point D d be Rid, and the inner peripheral radius of point E e be Rie. According to the above configuration, during compression deformation, the middle part between the first end and the second end of the spring member 2c deforms so as to fall inward in the radial direction, and it is possible to suppress a decrease in the inner diameter of the compression spring 1. Therefore, it is possible to suppress interference during the expansion and contraction operation of the compression spring 1 with respect to the member disposed inside the compression spring 1 in the radial direction.

[0024] The inner peripheral radius between point A a and point B b is the largest at point A a, the inner peripheral radius between point B b and point C c is the largest at point B b, the inner peripheral radius between point C c and point D d is the largest at point D d, and the inner peripheral radius between point D d and point E e is the largest at point E e. According to the above configuration, during compression deformation, the middle part between the first end and the second end of the spring member 2c deforms so as to fall inward in the radial direction, and it is possible to further suppress a decrease in the inner diameter of the compression spring 1.

[0025] Each spring member 2c satisfies the following condition E in the state before elastic deformation. Condition E: θ < θa and θ < θe However, in the developed view, let the acute angle side angle formed by the straight line connecting the center of the first end and the center of the second end with respect to the circumferential direction be θ, the acute angle side angle formed by the straight line tangent to point A a on the predetermined path P with respect to the circumferential direction be θa, and the acute angle side angle formed by the straight line tangent to point E e on the predetermined path P with respect to the circumferential direction be θe. According to the above configuration, it is possible to further suppress stress concentration on the first end and the second end during the expansion and contraction operation.

[0026] Each spring member 2c has an S shape in the state before elastic deformation as viewed in the developed view. According to the above configuration, it is possible to further suppress stress concentration on the first end and the second end during the expansion and contraction operation.

[0027] The number of spring members 2c constituting the unit structure 2 is not particularly limited as long as it is multiple, and the circumferential spacing between the spring members 2c is also not particularly limited; however, from the viewpoint of obtaining the above-mentioned effect, it is preferable that the unit structure 2 has three spring members 2c arranged with equal phase shifts in the circumferential direction.

[0028] The compression spring 1 has a unit pair structure 3 consisting of a pair of unit structures 2 adjacent to each other in the axial direction and connected together, and the unit structures 2 have the same structure except that the winding directions of the plurality of spring members 2c are different. With the above configuration, the circumferential displacement between the first annular member 2a and the second annular member 2b during the expansion and contraction operation can be offset within the unit pair structure 3. The number of unit pair structures 3 constituting the compression spring 1 can be appropriately set according to the desired expansion and contraction stroke amount.

[0029] The compression spring 1 has a circular outer periphery when viewed in the axial direction, but is not limited thereto and may have, for example, a polygonal outer periphery.

[0030] The compression spring 1 is made of a polyolefin resin such as polypropylene or polyethylene. When a resin product incorporating the compression spring 1 is formed only from polyolefin resin in consideration of the environment such as recyclability, it is preferable to form the compression spring 1 from polypropylene, taking into account the elasticity and durability of the resin. The structure of the compression spring 1 in this embodiment is not limited to that made from polyolefin resin, and may be applied to a compression spring 1 made from a resin other than polyolefin resin, for example. Making the compression spring 1 from resin can increase the recyclability when the compression spring 1 is incorporated into a resin product.

[0031] In this embodiment, the discharge device 6 includes a compression spring 1, a cylinder 8, a piston 10, and an actuating member 11 that actuates the piston 10 relative to the cylinder 8 in response to an operation resisting the elastic force of the compression spring 1, thereby discharging fluid through the inside of the cylinder 8. According to the above-mentioned configuration, the entire discharge device 6 is made of resin, thereby realizing a discharge device 6 with high recyclability.

[0032] The operating member 11 has a push-down head 7 that is subjected to a push-down operation, a piston 10, and a stem 9 that is pushed down together with the piston 10 relative to the cylinder 8 by a push-down operation against the repulsive force of the compression spring 1, and that moves up together with the piston 10 relative to the cylinder 8 by the repulsive force of the compression spring 1 when the push-down operation is released, thereby sending the fluid in the cylinder 8 to the push-down head 7 and discharging it through the push-down head 7. With the above configuration, the discharge device 6 can be configured as a push-down head type pump. The discharge device 6 is not limited to being a push-down head type pump, and may be configured as, for example, a trigger type pump.

[0033] The stem 9 extends through the radial inside of the compression spring 1. In this embodiment, the above configuration regarding condition D makes it possible to suppress interference between the stem 9 arranged radially inside the compression spring 1 and the compression spring 1 during expansion and contraction, so that the compression spring 1 can be arranged with good space efficiency.

[0034] In this embodiment, the discharge container 4 includes a container body 5 having a mouth portion 5a, and a discharge device 6 attached to the mouth portion 5a and discharging the contents in the container body 5 by the expansion and contraction action of a compression spring 1. According to the above configuration, the entire discharge container 4 is made of resin, thereby realizing a discharge container 4 with high recyclability.

[0035] The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit and scope of the present invention. [Explanation of symbols]

[0036] 1 Compression spring 2 Unit structure 2a First annular member 2b Second annular member 2c Spring member 3 Unit vs. Structure 4 Discharge container 5 Container body 5a Mouth 6 Discharge device 7 Push-down head 8 Cylinders 9. Stem 10 Piston 11. Operating member a Point A b Point B c Point C d D point e Point E O center axis P Predetermined route Ria A radius of the inner periphery of point a Rib B Inner edge radius of point b Ric C: Inner edge radius of point c Rid D: Inner edge radius of point d Rie E: inner edge radius of point e Sa Cross-sectional area of ​​point A a Sb Cross-sectional area of ​​point b Sc C Cross-sectional area of ​​point c Sd Cross-sectional area of ​​point d Se Cross-sectional area of ​​point e θ The acute angle formed by the straight line connecting the center of the first end and the center of the second end with respect to the circumferential direction θa is the acute angle that the straight line tangent to the specified path P at point A a makes with respect to the circumferential direction. θe The acute angle that the straight line tangent to the specified path P at point E e makes with respect to the circumferential direction

Claims

1. a unit structure including a first annular member and the second annular member spaced apart from each other in an axial direction along a central axis line, and a plurality of spring members provided with a phase difference in a circumferential direction around the central axis line, each of the spring members linearly extending from a first end connected to the first annular member to a second end connected to the second annular member at a position shifted in the circumferential direction from the first end while continuously changing a cross-sectional area perpendicular to the predetermined path in a state before elastic deformation; Each of the spring members of the unit structure is a compression spring that satisfies the following condition A in a state before elastic deformation. Condition A: Sa>Sb>Sc, and Se>Sd>Sc However, the spring member is divided into four sections of equal length along the specified path from point A located at the first end to point B, from point B to point C, from point C to point D, and from point D to point E located at the second end, and the cross-sectional area of ​​point A is Sa, the cross-sectional area of ​​point B is Sb, the cross-sectional area of ​​point C is Sc, the cross-sectional area of ​​point D is Sd, and the cross-sectional area of ​​point E is Se.

2. The compression spring according to claim 1 , wherein each of the spring members satisfies the following condition B before the elastic deformation: Condition B: 0.4≦Rca≦0.75 and 0.4≦Rce≦0.75 Here, Sc / Sa=Rca, and Sc / Se=Rce.

3. The compression spring according to claim 1 , wherein each of the spring members satisfies the following condition C before the elastic deformation: Condition C: 40°≦θ≦60° In this regard, when viewed in a developed view, the acute angle that a straight line connecting the center of the first end and the center of the second end forms with respect to the circumferential direction is defined as θ.

4. 2. The compression spring of claim 1, wherein, in a state before the elastic deformation, each of the spring members has the predetermined path extending along the axial direction from the first end to the second end within a region located between the two annular members, an inner peripheral radius, which is a radius perpendicular to the central axis at the inner peripheral edge of the spring member when viewed in the axial direction, changes continuously, and the following condition D is satisfied: Condition D: Ria<Rib<Ric, and Rie<Rid<Ric Here, the inner peripheral radius of point A is Ria, the inner peripheral radius of point B is Rib, the inner peripheral radius of point C is Ric, the inner peripheral radius of point D is Rid, and the inner peripheral radius of point E is Rie.

5. A compression spring according to claim 1; A cylinder; The piston and an actuating member for actuating the piston relative to the cylinder in response to operation against the elastic force of the compression spring, thereby discharging fluid through the interior of the cylinder.

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