JP2024016517A - Multistep damper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a damper capable of suppressing the rotating speed of a rotary body stepwise.

SOLUTION: At least the peripheral face of an installation wall 50 of a single side body 8 rotatable integrally with a rotary body 6 is formed of a synthetic resin material which has such characteristics that a slide resistance is increased in a proportion as a relative rotating speed to a member having close contact therewith is increased. Two single side bodies 8 with the peripheral faces of which a coil spring 10 has close contact are arranged in series with each other in the axial direction so that a first coil spring 10a mounted to the first single side body 8a is non-rotatable relative to a housing 4 as a fixing member and a second coil spring 10b mounted to the second single side body 8b is non-rotatable relative to the other side body 12, and the other side body 12 is rotatable only in a required angle range relative to the housing 4.

SELECTED DRAWING: Figure 1

COPYRIGHT: (C)2024,JPO&INPIT

Description

The present invention relates to a multi-stage damper.

BACKGROUND ART Some blinds installed indoors have a plurality of vertically arranged slats that extend horizontally and are movable vertically. In such a type of blind, a plurality of slats are connected via lifting cords that extend vertically, and one end of the lifting cord is connected to a bottom rail that extends horizontally parallel to the slats, and the other end of the lifting cord is connected to a bottom rail that extends horizontally parallel to the slats. are respectively connected to the output rotating members of the winding mechanism in the head box. An operating cord is connected to the input rotating member of the winding mechanism, and by operating the operating cord and rotating the input rotating member in forward and reverse directions, the bottom rail connected to the output rotating member via the lifting cord is rotated. It moves up and down, thereby making it possible to move a plurality of slats in the vertical direction. The winding mechanism is usually equipped with a stopper (sometimes called a cord lock) that holds the operating cord, and by forcing the operating cord in one direction (usually outward), the operating cord can be locked. It can be held at any position, and the bottom rail can be fixed at any height position (vertical position). With the operating cord being held by the stopper, the holding is released by forcing the operating cord in the other direction in the left and right direction.

As mentioned above, the input rotating member and the output rotating member rotate in conjunction with each other, so for example, when the operating cord is operated to raise the bottom rail, if the operating cord is not held by the stopper, the operating cord will be disconnected from the operating cord. When the hand is released, the bottom rail falls freely and collides with the floor, or the lifting cord is pulled out to the maximum extent, and a shock is applied to the winding mechanism. This also applies when the operation cord is released from being held by the stopper and the bottom rail falls freely. In order to prevent such free fall of the bottom rail, a damper may be provided in the winding mechanism to limit the downward speed of the bottom rail.

As an example of such a damper, there is a damper shown in Patent Document 1 below, which was filed by the applicant of the present application prior to the present application and has already been patented. This damper includes a cylindrical housing as a fixed member, a shaft-shaped rotating body rotatable with respect to the housing, and a coil spring combined with the rotating body. At least the outer circumferential surface of the rotating body is formed of a synthetic resin material having a characteristic that sliding resistance increases as the relative rotational speed with the member brought into close contact therewith increases. In the damper disclosed in Patent Document 1 below, the entire rotating body is formed of a synthetic resin material having the above characteristics. The coil spring includes a winding part in which a wire is spirally wound one to three times, and a hook part from which the wire extends from the winding part. In the coil spring, the inner circumferential surface of the winding portion is brought into close contact with the outer circumferential surface of the rotating body, and the hook portion is held by the housing, so that the coil spring cannot rotate with respect to the housing. When the rotating body rotates, the hook portion of the coil spring is pushed by the housing in a direction that weakens the close contact between the inner circumferential surface of the winding portion and the outer circumferential surface of the rotating body. A rotating body slides on the coil spring. Since the rotating body is made of a synthetic resin material having the above characteristics, when the rotating body attempts to rotate while accelerating, for example, the rotating body is connected to a freely falling member such as the above-mentioned bottom rail. Even when the rotational speed of the rotating body is suppressed.

Patent No. 7088993

According to the damper shown in Patent Document 1, it is possible to suppress the rotational speed of the rotating body that is trying to rotate while accelerating, but depending on the usage, the rotation of the rotating body can be suppressed while the rotating body is rotating. It may be necessary to further reduce the speed. For example, in the initial stage of rotation immediately after the rotating body starts rotating, the rotational speed of the rotating body is not high, so the rotational speed of the rotating body is not excessively suppressed (partially suppressed), and the rotational speed of the rotating body is not suppressed excessively. There are cases where it is required to sufficiently suppress the rotational speed of the rotating body after the rotational speed has increased to a certain extent.

The present invention has been made in view of the above facts, and its main technical problem is to improve the damper shown in Patent Document 1 above to make it possible to suppress the rotational speed of a rotating body in stages. The purpose is to provide a damper.

As a result of extensive studies, the present inventor has found that the sliding resistance of at least the circumferential surface of a mounting wall provided on a one-sided body that is rotatable integrally with the rotating body increases as the relative rotational speed of the mounting wall with a member that is brought into close contact therewith increases. Two half bodies made of a synthetic resin material with special characteristics and having a coil spring closely attached to the circumferential surface are arranged in series in the axial direction, and the coil spring attached to one half body is attached to the fixed member. By making the coil spring attached to the other side body non-rotatable with respect to the other side body, and making the other side body rotatable only within the required angle range with respect to the fixed member, the above-mentioned We have found that the main technical problems can be solved.

That is, according to the present invention, a damper that solves the above-mentioned main technical problem includes a fixed member, a rotating body rotatable with respect to the fixed member, and integrally connected to the rotating body on the rotation axis of the rotating body. a first side body and a second side body that are rotatable, a first coil spring and a second coil spring that are combined with the first side body and the second side body, respectively; the other side body being rotatable within a required angular range with respect to the fixed member on the axis;
The first half body and the second half body are arranged in series in the axial direction and both include mounting walls having a circumferential surface having a circular cross section, and at least the circumferential surface of the mounting wall is brought into close contact therewith. It is made of a synthetic resin material that has the characteristic that sliding resistance increases as the relative rotational speed with the member increases.
The first coil spring and the second coil spring both include a winding part in which a wire is spirally wound one to three times, and a hook part from which the wire extends from the winding part,
The circumferential surface of the winding portion of the first coil spring is brought into close contact with the circumferential surface of the mounting wall of the first half body, and the hook portion is held by the fixing member, so that the first the coil spring cannot rotate relative to the fixed member;
The circumferential surface of the winding portion of the second coil spring is brought into close contact with the circumferential surface of the mounting wall of the second side body, and the hook portion is held by the other side body, so that the second coil spring The coil spring cannot rotate with respect to the other side body,
When the rotating body rotates by the required angle in one direction from the initial position, the hook portion of the first coil spring is attached to the circumferential surface of the winding portion and the circumferential surface of the mounting wall by the fixing member. The first side body slides against the first coil spring, and the second side body slides against the second coil spring and the other side body. It rotates as one with the
When the rotating body rotates in the one direction beyond the required angle from the initial position, the first half body continues to slide against the first coil spring, and the second side body continues to slide against the first coil spring. The hook portion of the coil spring is pushed by the other side body in a direction that weakens the close contact between the circumferential surface of the winding portion and the circumferential surface of the mounting wall, and the second side body also pushes against the second side body. A multi-stage damper is provided that slides against a coil spring.

Preferably, the hook portions are formed at both ends of the winding portion in the axial direction. In this case, the first half-body and the second half-body are preferably connected to the rotating body via a one-way clutch. Furthermore, it is preferable that the rotating body is equipped with an auxiliary coil spring that cannot rotate with respect to the second half body. The fixing member is a cylindrical housing, and inside the housing there are provided the first half body and the second coil spring in which the first coil spring is brought into close contact with the outer peripheral surface of the mounting wall. Preferably, the second half bodies are housed in close contact with the outer peripheral surface of the mounting wall. The synthetic resin material is preferably PPS or PA. In this case, it is preferable that carbon filler or carbon black is added to the synthetic resin material. Preferably, two of the first coil springs and two of the second coil springs are combined with each of the first half body and the second half body. Preferably, a lubricant is applied to the first coil spring and the second coil spring.

In the damper of the present invention, at least the circumferential surface of the mounting wall of the one side body is formed of a synthetic resin material having a characteristic that sliding resistance increases as the relative rotational speed with the member brought into close contact therewith increases. This damper is similar to the damper disclosed in Patent Document 1 above in that it can suppress the rotational speed of a rotating body that is attempting to rotate while accelerating. Further, in the damper of the present invention, two half bodies to which coil springs are attached are arranged in series in the axial direction, and the coil spring attached to one half body cannot rotate with respect to the fixed member. At the same time, the coil spring attached to the other side body cannot rotate with respect to the other side body, and the other side body can only rotate within a required angular range with respect to the fixed member. Therefore, when the rotating body rotates, one side body starts sliding against the coil spring attached to it and rotates by the above-mentioned required angle, and then the other side body starts sliding against the coil spring attached to it. Since it starts sliding against the spring, it becomes possible to suppress the rotational speed of the rotating body in stages.

The applicant of this application has previously filed Japanese Patent Application No. 2017-96469 and Japanese Patent Application No. 2018-207524 as a multi-stage braking device that reduces the rotational speed of a rotating body in stages, and both of these applications are It has already been patented (Patent No. 6560295 and Patent No. 6790041). In these multistage braking devices, braking torque is applied to the rotating body in stages according to the rotation angle of the rotating body. Therefore, even with the multistage braking device described above, the rotational speed of the rotating body can be reduced in stages. However, in the above multi-stage braking device, no consideration is given to the unique relationship that exists between two sliding members, that is, the relationship in which sliding resistance increases as the rotational speed increases. Therefore, when the braking torque is applied in stages, there is a risk that an undesirable impact will occur, and a sufficient damper effect (damping effect) may not always be obtained. Furthermore, in the multi-stage braking device, the rotating body is structurally limited to reciprocating within a predetermined angular range.

1 is a diagram illustrating a preferred embodiment of a damper constructed according to the present invention. FIG. 2 is a diagram showing the housing of the damper shown in FIG. 1 as a single unit. FIG. 2 is a diagram showing a single rotating body of the damper shown in FIG. 1; FIG. 2 is a diagram illustrating one side of the damper shown in FIG. 1; FIG. 2 is a diagram showing a single coil spring of the damper shown in FIG. 1; FIG. 2 is a diagram showing the other side body of the damper shown in FIG. 1 alone. FIG. 2 is a diagram showing a state in which a rotating body has rotated a required angle in one direction from the state shown in FIG. 1;

Hereinafter, preferred embodiments of a damper constructed according to the present invention will be described in more detail with reference to the accompanying drawings. In addition, in the following description, "one side in the axial direction" and "the other side in the axial direction" are based on the vertical cross-sectional view in the upper row of FIG. 1, unless otherwise specified, and "one side in the axial direction" refers to the left side in the figure. "Other side in the axial direction" refers to the right side in the figure.

To explain with reference to FIG. 1, the damper, which is designated by the number 2 as a whole, includes a cylindrical housing 4 as a fixed member, a rotating body 6, a first half body 8a, a second half body 8b, and a second half body 8a. It includes one coil spring 10a and 10b and the other side body 12.

Referring to FIGS. 1 and 2, the housing 4 is comprised of a housing body designated by numeral 14 and a shield designated by numeral 16. The housing body 14 includes a substantially square fixed end plate 18 disposed perpendicularly to the axial direction, and a rectangular cylindrical fixed outer peripheral wall 20 extending from the outer peripheral edge of the fixed end plate 18 toward the other side in the axial direction. It is cup-shaped with a A circular through hole 22 is formed in the center of the fixed end plate 18, passing through in the axial direction. A shoulder surface 24 is formed in the axially intermediate portion of the inner circumferential surface of the fixed outer circumferential wall 20 and extends in an annular shape perpendicular to the axial direction and facing the other side in the axial direction. The space is divided into a one-sided space 26 on one side of the shoulder surface 24 in the axial direction and a second space 28 on the other side of the shoulder surface 24 in the axial direction. The cross-sectional shapes of the one-side space 26 and the other-side space 28 are both circular. An arc-shaped fixed support wall 30 is formed in the one-sided space 26 and protrudes from the fixed end plate 18 toward the other side in the axial direction along the inner circumferential surface of the fixed outer circumferential wall 20 . When viewed in the axial direction, both circumferential end surfaces of the fixed support wall 30 are located on a common straight line, and the both end surfaces constitute fixed locking surfaces 32x and 32y, respectively. Further, in the one-side space 26, a fixing auxiliary column 34 having a substantially right triangular cross section is also formed, which protrudes from the fixed end plate 18 toward the other side in the axial direction along the inner circumferential surface of the fixed outer circumferential wall 20. When viewed in the axial direction, the auxiliary fixing column 34 is located offset toward the fixed locking surface 32x of the fixed support wall 30, and the inner surface of the auxiliary fixing column 34 is parallel to the fixed locking surface 32x. Both the fixed support wall 30 and the fixed auxiliary column 34 are raised from the other axial side of the fixed end plate 18 to the other axial end of the one-sided space 26, and the height from the other axial side of the fixed end plate 18 is increased. are equal. An arcuate recess 36 is formed in the other side space 28 in which the inner diameter of the fixed outer circumferential wall 20 is increased over a required angular range. Screw holes 38 are formed at each corner of the axial end surface of the fixed outer circumferential wall 20 .

The shield 16 is a substantially square flat plate corresponding to the fixed end plate 18 of the housing body 14. A circular through hole 40 is formed in the center of the shield 16 and extends through the shield 16 in the axial direction. A circular hole 42 is formed at each corner of the shield 16. By inserting bolts (not shown) into the respective blind holes 42 and fastening them to the screw holes 38 formed in the housing body 14, the shield 16 closes the other axial side of the housing body 14 and is fixed thereto. Ru.

Referring to FIGS. 1 and 3, in the illustrated embodiment, the rotating body 6 is a solid shaft-like member that is rotatable with respect to the housing 4. As shown in FIG. The rotation axis of the rotating body 6 is indicated by the symbol o. The cross-sectional shape of the main portion 44 (excluding the other end in the axial direction) of the rotating body 6 is circular. Supported parts 46 whose outer diameters are slightly reduced are provided at both ends of the main part 44 in the axial direction. The shield is inserted into the through hole 22 formed in the shield 16 and rotatably supported by the housing body 14, and the supported part 46 located on the other axial side is inserted into the through hole 40 formed in the shield 16. It is rotatably supported by 16. The cross section of the other end in the axial direction of the rotating body 6 has a circular shape with a part cut out, and a connecting portion 48 connected to an external device is provided here.

As shown in FIG. 1, the first half body 8a and the second half body 8b are arranged in series in the axial direction on the rotation axis o of the rotary body 6, and the first half body 8a and the second half body 8b are arranged in series on the rotation axis o of the rotary body 6. It can rotate together with 6. Since the first half body 8a and the second half body 8b have the same configuration, when explaining each part of the first half body 8a and the second half body 8b, the first half body 8a and the second half body 8b are 8a and the second half body 8b are collectively referred to simply as "one half body 8." Referring also to FIG. 4, in the illustrated embodiment, the one side body 8 includes a cylindrical mounting wall 50 extending in the axial direction, and is connected to the other end of the mounting wall 50 in the axial direction. A vertical disc-shaped end plate 52 is provided. The cross-sectional shape of the outer peripheral surface of the one-sided body mounting wall 50 is circular. At the other end in the axial direction of the inner circumferential surface of the mounting wall 50, an annular support protrusion 54 is formed that protrudes inward in the radial direction and continues in the circumferential direction. The main portion 44 of the rotating body 6 is inserted inside the support protrusion 54 . Three retaining protrusions 56 are formed on the inner circumferential surface of the mounting wall 50 at intervals in the circumferential direction, which protrude inward in the radial direction and extend linearly in the axial direction. A recess 58 is formed in the center of the other axial side of the end plate 52, and due to this, when the one-sided body 8 is viewed from the other axial side, the other axial side of the support ridge 54 is partially recessed. be exposed to. When viewed from the other side in the axial direction, the recess 58 has a shape formed by joining a circular portion 58p and a substantially D-shaped portion 58q. The peripheral edge of the portion 58p surrounds the inner peripheral edge of the support ridge 54, and the center portion of the portion 58p communicates with the inside of the mounting wall 50. A linear portion of portion 58q is joined to portion 58p, and auxiliary locking surfaces 60x and 60y are provided at both ends of the linear portion.

Here, at least the circumferential surface (in the illustrated embodiment, the outer circumferential surface) of the mounting wall 50 of the one-sided body 8 has a characteristic that sliding resistance increases as the relative rotational speed with the member brought into close contact therewith increases. It is made of synthetic resin material with In the illustrated embodiment, the entire half body 8 is made of a synthetic resin material having the above characteristics. Such synthetic resin materials include, for example, PPS (polyphenylene sulfide) or PA (polyamide), and from the viewpoint of improving the wear resistance of the rotating body 6, carbon filler or carbon black is added to these synthetic resin materials. It is preferable to add.

As shown in the upper longitudinal sectional view of FIG. 1, in the illustrated embodiment, the half body 8 is connected to the rotating body 6 via a one-way clutch 62. The one-way clutch 62 is well known, and for example, the one shown in Japanese Patent No. 3501352, which was filed and patented by the applicant prior to the present application, is widely used in practice. For details of such one-way clutch 62, please refer to the above-mentioned patent document. The one-way clutch 62 is supported in the axial direction by the support ridges 54 inside the mounting wall 50 of the one-sided body 8 and is locked against relative rotation by the holding ridges 56, and is integral with the one-sided body 8. The main part 44 of the rotating body 6 is inserted into the one-way clutch 62, and the main part 44 of the rotating body 6 prevents the rotating body 6 from relative rotation in one direction. However, relative rotation in other directions is allowed. From this, when the rotating body 6 rotates in one direction, the rotation of the rotating body 6 is transmitted to the one-sided body 8, and the rotating body 6 and the one-sided body 8 rotate together, but the rotating body 6 rotates in the other direction. When doing so, the rotation of the rotating body 6 is not transmitted to the one-sided body 8, and the rotating body 6 and the one-sided body 8 rotate relative to each other.

As shown in FIG. 1, the first coil spring 10a and the second coil spring 10b are combined with the first half body 8a and the second half body 8b, respectively. In the illustrated embodiment, two first coil springs 10a and two second coil springs 10b are combined with each of the first half body 8a and the second half body 8b. Since the first coil spring 10a and the second coil spring 10b have the same configuration, when describing each part of the first coil spring 10a and the second coil spring 10b, the first coil spring 10a and the second coil spring 10b will be collectively referred to simply as "coil spring 10." Explaining with reference to FIG. 5, the coil spring 10 includes a winding portion 64 in which a wire rod having a circular cross section is spirally wound one to three times. Regarding the number of turns of the wire rod in the winding portion 64, please refer to the above-mentioned Patent Document 1. In the illustrated embodiment, the wire is wound once in the winding portion 64. The coil spring 10 further includes a hook portion from which the wire extends from the winding portion 64. In the illustrated embodiment, the hook portions are provided at both ends of the winding portion 64 in the axial direction, and are designated by reference numerals 66x and 66y. The hook portions 66x and 66y both linearly extend from both ends of the winding portion 64 in the axial direction in opposite directions. When the coil spring 10 is in a free state, that is, when no external force is applied to the hook parts 66x and 66y, the inner diameter of the winding part 64 is smaller than the outer diameter of the mounting wall 50 of the one-sided body 8, and the coil spring 10 is mounted on the outer peripheral surface of the mounting wall 50 with the wound portion 64 expanded in diameter. Therefore, the coil spring 10 always tightens the outer peripheral surface of the mounting wall 50 of the one-sided body 8 by its restoring force. Therefore, the coil spring 10 is attached to the one-sided body 8 so that the inner circumferential surface of the winding portion 64 closely contacts the outer circumferential surface of the mounting wall 50. A lubricant is applied to the coil spring 10. The side body 8 to which the coil spring 10 is attached will be further referred to later.

As shown in FIG. 1, the other side body 12 is disposed in the other side space 28 of the housing body 14 and is supported from both sides in the axial direction by the shoulder surface 24 and the shield 16, and the other side body 12 is arranged on the rotation axis o. It is rotatable with respect to the housing 4 within a required angular range. Referring also to FIG. 6, the other side body 12 has an overall cylindrical shape, and has a movable end plate 68 disposed perpendicularly to the axial direction, and the other side in the axial direction from the outer peripheral edge of the movable end plate 68. It has a cylindrical movable outer circumferential wall 70 extending toward the outer wall 70 . A circular through hole 72 that penetrates in the axial direction is formed in the center of the movable end plate 68, and the main portion 44 of the rotating body 6 is inserted into the through hole 72. On the outer circumferential surface of the other side body 12, a restricting piece 74 having an arc-shaped cross section and whose outer diameter is increased over a required angular range extends throughout the entire axial direction. As shown in the BB sectional view of FIG. 1, the limiting piece 74 is positioned in the recess 36 formed in the other side space 28. Thereby, the other side body 12 can be rotated only within a required angular range with respect to the housing 4 on the rotation axis o. An arc-shaped movable support wall 76 is formed inside the movable outer circumferential wall 70 and protrudes from the movable end plate 68 toward the other side in the axial direction along the inner circumferential surface of the movable outer circumferential wall 70 . When viewed in the axial direction, both circumferential end surfaces of the movable support wall 76 are located on a common straight line, and the both end surfaces constitute movable locking surfaces 78x and 78y, respectively. A movable auxiliary column 80 having a substantially right triangular cross section is also formed inside the movable outer circumferential wall 70 and protrudes from the movable end plate 68 toward the other side in the axial direction along the inner circumferential surface of the movable outer circumferential wall 70 . When viewed in the axial direction, the movable auxiliary column 80 is located offset toward the movable locking surface 78x of the movable support wall 76, and the inner surface of the movable auxiliary column 80 is parallel to the movable locking surface 78x. The movable support wall 76 and the movable auxiliary column 80 both protrude from the other axial side of the movable end plate 68 to the other axial end of the movable outer circumferential wall 70, and the height from the other axial side of the movable end plate 68 increases. are equal.

The one-sided body 8 to which the coil spring 10 is mounted will be further explained with reference to FIG. 1. The first side body 8a to which the first coil spring 10a is attached is arranged in the side space 26 of the housing body 14. As shown in the AA sectional view, the outer circumferential surface of the winding portion 64 of the first coil spring 10a faces the inner circumferential surface of the fixed support wall 30 of the housing body 14, and the hook portions 66x and 66y are fixedly engaged. They are close to or in contact with the surfaces 32x and 32y, respectively. As a result, the hook portions 66x and 66y are held by the housing 4, and the first coil spring 10a cannot rotate relative to the housing 4. On the other hand, the second side body 8b to which the second coil spring 10b is attached is arranged inside the other side body 12 accommodated in the other side space 28 of the housing body 14. As shown in the BB sectional view, the outer circumferential surface of the winding portion 64 of the second coil spring 10b faces the inner circumferential surface of the movable support wall 76 of the other side body 12, and the hook portions 66x and 66y are movably engaged. The stop surfaces 78x and 78y come close to or come into contact with each other. Thereby, the hook portions 66x and 66y are held by the other side body 12, and the second coil spring 10b becomes unrotatable with respect to the other side body 12.

As shown in FIG. 1, in the illustrated embodiment, the rotating body 6 is further equipped with an auxiliary coil spring 82 that cannot rotate with respect to the second half body 8b. As shown in the CC cross-sectional view, the auxiliary coil spring 82, like the coil spring 10, has a winding part 84 around which a wire is wound, hook parts 86x from which the wire extends from both ends of the winding part 84 in the axial direction; 86y. The number of turns of the wire in the winding section 84 is arbitrary. When the auxiliary coil spring 82 is in a free state, that is, when no external force is applied to the hook parts 86x and 86y, the inner diameter of the winding part 84 is smaller than the outer diameter of the main part 44 of the rotating body 6, and the auxiliary coil The spring 82 is attached to the outer circumferential surface of the main portion 44 with the winding portion 84 expanded in diameter. Therefore, the auxiliary coil spring 82 always tightens the outer peripheral surface of the main portion 44 of the rotating body 6 by its restoring force. The auxiliary coil spring 82 attached to the outer peripheral surface of the main portion 44 of the rotating body 6 is located in a recess 58 formed in the end plate 52 of the second half body 8b. More specifically, in the recess 58 of the auxiliary coil spring 82, the outer circumferential surface of the winding portion 84 faces the inner circumferential surface of the end plate 52, and the hook portions 86x and 86y are close to or in contact with the auxiliary locking surfaces 60x and 60y, respectively. come into contact with As a result, the hook portions 86x and 86y are held by the second half-body 8b, and the auxiliary coil spring 82 cannot rotate relative to the second half-body 8b.

Next, the operation of the damper 2 will be explained with reference to FIGS. 1 and 7. First, a case will be described in which the rotating body 6 rotates in one direction from the state shown in FIG. 1 (this is taken as the initial position), that is, in the counterclockwise direction when viewed from the right direction in the upper vertical cross-sectional view of FIG. When the rotating body 6 is in the initial position, the one-way upstream side surface of the restriction piece 74 of the other side body 12 contacts the one-way upstream side surface of the recess 36 formed in the housing body 14 . When the rotating body 6 rotates in one direction, the one-way clutch 60 rotates together with the rotating body 6. Therefore, when the rotating body 6 rotates by a required angle in one direction from the initial position, the hook portion 66x of the first coil spring 10a combined with the first side body 8a is connected to the fixed engagement formed on the housing body 14. The stop surface 32x pushes the inner circumferential surface of the winding portion 64 and the outer circumferential surface of the mounting wall 50 in a direction where the close contact between them becomes weaker (in other words, in a relatively opposite direction), and the mounting wall 50 of the first half body 8a It slides against the winding portion of the first coil spring 10a. On the other hand, although the hook portion 66x of the second coil spring 10b combined with the second side body 8b also pushes the movable locking surface 78x formed on the other side body 12 in one direction, Since the limiting piece 74 of the other side body 12 can rotate in one direction in the recess 36, the second side body 8b rotates in one direction together with the second coil spring 10b and the other side body 12. do. Therefore, when the rotating body 6 rotates by a required angle in one direction from the initial position, the mounting wall 50 of the second half body 8b does not slide against the winding portion 64 of the second coil spring 10b. At this time, the auxiliary coil spring 82 also rotates in one direction together with the second half body 8b.

When the rotary body 6 rotates by the required angle in one direction from the initial position shown in FIG. 1, it becomes the state shown in FIG. By contacting the downstream side in one direction, the other side body 12 is prevented from further rotating in one direction with respect to the housing 4. Therefore, when the rotating body 6 further rotates in one direction from the state shown in FIG. At the same time, the hook portion 66x of the second coil spring 10b combined with the second side body 8b is attached to the inner periphery of the winding portion 64 by the movable locking surface 78x formed on the other side body 12. The mounting wall 50 of the second half body 8b is also pushed in the direction where the close contact between the surface and the outer circumferential surface of the mounting wall 50 is weakened (in other words, in the other direction), and the mounting wall 50 of the second half body 8b is also pushed against the winding portion of the second coil spring 10b. and slide. At this time, the hook portion 86x of the auxiliary coil spring 82 attached to the outer circumferential surface of the main portion 44 of the rotating body 6 is attached to the inner circumference of the winding portion 84 by the auxiliary locking surface 60x formed on the second side body 8b. The main portion 44 of the rotating body 6 also slides against the winding portion 84 of the auxiliary coil spring 82 as it is pushed in a direction where the close contact between the surface and the outer circumferential surface of the main portion 44 becomes weaker (in other words, in a relatively opposite direction). .

Here, at least the outer circumferential surface of the mounting wall 50 of the one-sided body 8 is formed of a synthetic resin material that has a characteristic that sliding resistance increases as the relative rotational speed with the member that is brought into close contact therewith increases. Even if the rotating body 6 attempts to rotate while accelerating, the damper 2 of the present invention can suppress the rotational speed of the rotating body 6. In the damper of the present invention, two half bodies 8 to which coil springs 10 are attached are arranged in series in the axial direction, and the first coil spring 10a attached to the first half body 8a is The second coil spring 10b attached to the second side body 8b is not rotatable with respect to the housing 4, and is not rotatable with respect to the other side body 12. Rotation is possible only within the required angular range. Therefore, when the rotating body 6 rotates, the first side body 8a starts sliding with respect to the first coil spring 10a attached thereto and rotates by the above-mentioned required angle, and then the second side body 8a starts sliding with respect to the first coil spring 10a attached thereto. Since the body 8b starts sliding with respect to the second coil spring 10b attached thereto, it becomes possible to suppress the rotational speed of the rotating body 6 in stages. In the illustrated embodiment, the rotating body 6 also starts sliding against the auxiliary coil spring 82 at the same time as the second side body 8b starts sliding against the second coil spring 10b. That will happen.

When the rotating body 6 rotates in the other direction, the one-way clutch 62 rotates relative to the rotating body 6. Therefore, when the rotating body 6 rotates in the other direction by the required angle from the state shown in FIG. 7, the first half body 8a is held by the first coil spring 10a, and the rotating body 6 8a and the first coil spring 10a attached thereto, it rotates without receiving substantially any resistance. The rotating body 6 rotates without receiving substantially any resistance from the second side body 8b and the second coil spring 10b attached thereto, but an auxiliary coil spring 82 is also provided on the outer peripheral surface of the main portion 44. When the rotating body 6 rotates in the other direction due to the attachment, the hook portion 86y of the auxiliary coil spring 82 pushes the auxiliary locking surface 60y formed on the second half body 8b in the other direction. In order to rotate the second half body 8b and the second coil spring 10b attached thereto in the other direction, some resistance is encountered based on the inertia of the second half body 8b.

When the rotating body 6 rotates by the required angle in the other direction from the state shown in FIG. 7, it becomes the state shown in FIG. The other side body 12, the second coil spring 10b, and the auxiliary coil spring 82 are in contact with the downstream side surface (one upstream side surface) in the other direction of the recess 36 formed in the housing body 14, and are moved in the other direction with respect to the housing 4. rotation is prevented. Therefore, when the rotating body 6 further rotates from the state shown in FIG. The auxiliary locking surface 60y pushes the inner circumferential surface of the winding portion 84 and the outer circumferential surface of the main portion 44 of the rotating body 6 in a direction that weakens the close contact (in other words, in one direction relatively), and the rotating body 6 The main portion 44 slides against the winding portion 84 of the auxiliary coil spring 82.

Therefore, if the external device is connected to, for example, a winding mechanism of a blind, and the bottom rail is in the raised position in the initial position shown in FIG. 1, the rotating body 6 will rotate in one direction when the bottom rail falls freely. Then, during the initial stage of free fall of the bottom rail, that is, while the rotating body 6 rotates by the above-mentioned required angle, only the first side body 8a slides against the first coil spring 10a, and the rotating body 6 rotates at the above-mentioned required angle. After rotation, the first half body 8a slides against the first coil spring 10a, and the second half body 8b also slides against the second coil spring 10b (furthermore, the rotating body 6 also slides against the second coil spring 10b). (slides against the auxiliary coil spring 82). At this time, the circumferential surface of the mounting wall 50 of the first side body 8a and the second side body 8b that slide with respect to the first coil spring 10a and the second coil spring 10b (in the illustrated embodiment, The entire half body 8) is made of a synthetic resin material that has the characteristic that the sliding resistance increases as the relative rotational speed with the member that is brought into close contact with it increases, so the falling speed of the bottom rail gradually decreases. be suppressed. When the lowered bottom rail is raised using the operation cord, due to the presence of the one-way clutch 60, the first side body 8a is moved relative to the first coil spring 10a, and the second side body Since the rotating body 6 can be rotated in the other direction without sliding the coil springs 8b and 8b relative to the second coil springs 10b, the rotating body 6 can be operated with a light force.

The multi-stage damper constructed according to the present invention has been described above in detail with reference to the attached drawings, but the present invention is not limited to the embodiments described above, and appropriate modifications may be made without departing from the scope of the present invention. or change is possible. For example, in the illustrated embodiment, the first half body 8a and the second half body 8b are connected to the rotating body 6 via a one-way clutch 60, and the damper is applied only when the rotating body 6 rotates in one direction. Although the effect was exerted, if the one-way clutch 60 is omitted, a damper effect can be exerted when rotating in both forward and reverse directions. When the one-way clutch 60 is omitted, the rotating body, the first half-body, and the second half-body do not necessarily need to be separate bodies, and may be integrated. If the rotation direction of the rotating body 6 is only one direction, the first coil spring and the second coil spring may have a single hook portion. Further, in the illustrated embodiment, the fixing member is a cylindrical housing and the rotating body is shaft-shaped, but the fixing member can be shaft-shaped and the rotating body can also be cylindrical. When the fixed member is shaft-shaped and the rotating body is cylindrical, the internal and external relationships of the other constituent members are all reversed.

2: Damper 4: Housing (fixed member)
6: Rotating body 8a: First side body 8b: Second side body 10a: First coil spring 10b: Second coil spring 12: Other side body 50: Mounting wall 62: One-way clutch 64: Winding Parts 66x and 66y: Hook part 82: Auxiliary coil spring o: Rotation shaft

Claims (9)

a fixed member, a rotary body rotatable with respect to the fixed member, a first half body and a second half body rotatable together with the rotary body on a rotation axis of the rotary body; a first coil spring and a second coil spring that are combined with the first side body and the second side body, respectively; and the other side body that is rotatable within a required angle range with respect to the fixed member on the rotation axis. and
The first half body and the second half body are arranged in series in the axial direction and both include mounting walls having a circumferential surface having a circular cross section, and at least the circumferential surface of the mounting wall is brought into close contact therewith. It is made of a synthetic resin material that has the characteristic that sliding resistance increases as the relative rotational speed with the member increases.
The first coil spring and the second coil spring both include a winding part in which a wire is spirally wound one to three times, and a hook part from which the wire extends from the winding part,
The circumferential surface of the winding portion of the first coil spring is brought into close contact with the circumferential surface of the mounting wall of the first half body, and the hook portion is held by the fixing member, so that the first the coil spring cannot rotate relative to the fixed member;
The circumferential surface of the winding portion of the second coil spring is brought into close contact with the circumferential surface of the mounting wall of the second side body, and the hook portion is held by the other side body, so that the second The coil spring is not rotatable with respect to the other side body,
When the rotating body rotates by the required angle in one direction from the initial position, the hook portion of the first coil spring is attached to the circumferential surface of the winding portion and the circumferential surface of the mounting wall by the fixing member. The first side body slides against the first coil spring, and the second side body slides against the second coil spring and the other side body. It rotates as one with the
When the rotating body rotates in the one direction beyond the required angle from the initial position, the first half body continues to slide against the first coil spring, and the second side body continues to slide against the first coil spring. The hook portion of the coil spring is pushed by the other side body in a direction that weakens the close contact between the circumferential surface of the winding portion and the circumferential surface of the mounting wall, and the second side body also pushes against the second side body. A multi-stage damper that slides against a coil spring. The multi-stage damper according to claim 1, wherein the hook portion is formed at both ends of the winding portion in the axial direction. The multistage damper according to claim 2, wherein the first half body and the second half body are connected to the rotating body via a one-way clutch. 4. The multistage damper according to claim 2, wherein the rotating body is equipped with an auxiliary coil spring that cannot rotate with respect to the second half body. The fixing member is a cylindrical housing, and inside the housing there are provided the first half body and the second coil spring in which the first coil spring is brought into close contact with the outer peripheral surface of the mounting wall. 2. The multi-stage damper according to claim 1, wherein said second half bodies are housed in close contact with the outer peripheral surface of said mounting wall. The damper according to claim 1, wherein the synthetic resin material is PPS or PA. The multi-stage damper according to claim 6, wherein carbon filler or carbon black is added to the synthetic resin material. 2. The multistage damper according to claim 1, wherein two of the first coil springs and two of the second coil springs are combined with each of the first half body and the second half body. The multi-stage damper according to claim 1, wherein a lubricant is applied to the first coil spring and the second coil spring.

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