Patent Description:
A shock absorber is generally mounted on a straddle type vehicle such as a two-wheel vehicle. In the shock absorber, a piston is provided in a cylinder, and the piston generates a damping force when the piston is displaced due to unevenness of a road surface or the like. Patent Literature <NUM> discloses a technique serving as a technique in the related art related to such a shock absorber. The shock absorber disclosed in Patent Literature <NUM> is used in a motorcycle or the like, and is provided with a detection unit including a sensor for detecting a displacement of a vehicle height.

Patent Literature <NUM> shows a shock absorber that includes a suspension spring configured to bias the shock absorber main body in an extension direction. It is possible to detect a displacement of a spring bearing at one position in a circumferential direction by a stroke sensor.

According to the shock absorber disclosed in Patent Literature <NUM>, since the shock absorber includes the sensor, the displacement of the vehicle height can be detected.

The shock absorber is a device which repeats expansion and contraction, and a load is applied to the sensor used in the shock absorber. An object of the present invention is to provide a shock absorber which can reduce a load which may be applied to the sensor.

As a result of intensive studies, the present inventors have found that (<NUM>) a coupling member is disposed between a receiving member receiving a spring and a sensor, and the receiving member and the sensor are coupled to each other via the coupling member, and (<NUM>) the coupling member allows a movement of the sensor along a circumferential direction of the receiving member and allows a movement of the sensor along an axial direction, so that a load which may be applied to the sensor can be reduced. The present invention is completed based on this finding.

Hereinafter, the present invention will be described.

According to a first aspect of the present invention, there is provided a shock absorber including:.

The receiving member may include a first flange portion which is the protruding portion formed into an annular shape around the axis,.

The receiving member may include a second recessed portion over a circumferential direction, the second recessed portion being the recessed portion formed into a recessed shape toward a center on an outer circumferential edge of the receiving member,.

The sensor may be disposed outside the cylinder.

The core portion may have a circular cross-sectional shape whose normal direction is an axial direction of the core portion.

The sensor may include a guide portion configured to guide a movement of the core portion along the axial direction of the core portion, and
the core portion may be disposed between the guide portion and the cylinder.

The guide portion may be disposed at a distance apart from the cylinder, and
the distance may be smaller than a width of the core portion in a radial direction of the cylinder.

According to a second aspect of the present invention, there is provided a shock absorber including:.

According to a third aspect of the present invention, there is provided a shock absorber including:.

According to the present invention, it is possible to provide a shock absorber which can reduce a load which may be applied to a sensor.

In the description, left and right refer to left and right with respect to an occupant of a vehicle, and front and rear refer to front and rear with respect to a traveling direction of the vehicle. In the drawings, Up indicates an upper direction, and Dn indicates a lower direction. The embodiments illustrated in the accompanying drawings are examples of the present invention, and the present invention is not limited to the embodiments.

Description will be made with reference to <FIG>. A shock absorber according to the present invention can be used as a front fork <NUM> or a rear cushion <NUM>. Hereinafter, the description will be made based on an example applied to the rear cushion <NUM> of a two-wheel vehicle <NUM> (an example in which the shock absorber according to the present invention is used as the rear cushion <NUM>. Hereinafter, the rear cushion <NUM> may be referred to as a "shock absorber <NUM>").

The two-wheel vehicle <NUM> (straddle type vehicle <NUM>) includes a vehicle body <NUM>, an engine <NUM> serving as a power source supported at a lower center portion of the vehicle body <NUM>, left and right front forks <NUM> (only the right front fork <NUM> is illustrated in the drawing) provided at left and right sides of a front portion of the vehicle body <NUM> and absorb an impact received due to unevenness of a road surface, a front wheel <NUM> which is interposed between the front forks <NUM> and is rotatably supported, handle pipes <NUM> which are disposed at upper portions of the front forks <NUM> and steer the front wheel <NUM>, a seat <NUM> provided above the engine <NUM> and on which an occupant sits, a swing arm <NUM> which extends from a rear portion of the vehicle body <NUM> to a rear side and which is swingable in an upper-lower direction, a rear wheel <NUM> which is rotatably supported by the swing arm <NUM>, and left and right rear cushions <NUM> (only the right rear cushion <NUM> is illustrated in the drawing) which are provided to cross from a rear portion of the vehicle body <NUM> to the swing arm <NUM>.

The left and right rear cushions <NUM> have the same configuration. Hereinafter, the right rear cushion <NUM> will be described, and the description of the left rear cushion will be omitted. The left and right rear cushions <NUM> may have different configurations depending on purposes.

An upper end of the shock absorber <NUM> is fixed to the vehicle body <NUM> and a lower end of the shock absorber <NUM> is fixed to the swing arm <NUM>.

Description will be made with reference to <FIG>. The shock absorber <NUM> includes a main body portion <NUM> which is located at an upper portion and is filled with oil, a rod unit <NUM> which is located at a lower portion and is provided to be able to move forward or backward relative to the main body portion <NUM>, a spring <NUM> which biases the main body portion <NUM> and the rod unit <NUM> so as to separate the main body portion <NUM> and the rod unit <NUM> from each other, and an adjustment unit <NUM> which adjusts a preload by displacing a position of an upper end of the spring <NUM> in a height direction (an upper-lower direction).

The main body portion <NUM> includes a main body portion stay <NUM> of which an upper portion is connected to the vehicle body <NUM> (see <FIG>) and a lower portion is formed into a cap shape, a cylindrical cylinder <NUM> of which an upper end is fastened to the main body portion stay <NUM>, and a spring receiving portion <NUM> (a receiving member <NUM>) which is provided at an outer side of the cylinder <NUM> to be able to move upward and downward and receives an upper end of the spring <NUM>.

The rod unit <NUM> includes a rod side stay <NUM> fixed to the swing arm <NUM> (see <FIG>), a substantially cylindrical piston rod <NUM> of which a lower end is fitted into the rod side stay <NUM>, a piston <NUM> which is fixed to a tip end of the piston rod <NUM> and located inside the cylinder <NUM>, and a spring receiving portion <NUM> which is fixed to the rod side stay <NUM> and receives a lower end of the spring <NUM>.

The spring <NUM> is implemented by a compression coil spring.

The adjustment unit <NUM> includes a jack portion <NUM> which comes into contact with the spring receiving portion <NUM> and displaces the spring receiving portion <NUM> downward by a hydraulic pressure, a pump <NUM> which is connected to the jack portion <NUM> and can feed oil, a sensor <NUM> which can detect a position of the spring receiving portion <NUM> in an axial direction of the cylinder <NUM> (for example, a distance between a lower end of a plunger <NUM> to be described later and the spring receiving portion <NUM>), an operation unit <NUM> for setting an adjustment amount of a preload, and a control unit <NUM> which operates the pump <NUM> based on information from the sensor <NUM> and the operation unit <NUM>.

The cylinder <NUM> includes an upper lid portion <NUM> to which the main body portion stay <NUM> is fixed, a cylinder main body <NUM> which is screwed to an inner circumference of the upper lid portion <NUM> and of which an upper end is closed, a lower lid portion <NUM> which closes a lower end of the cylinder main body <NUM>, and an extension portion <NUM> which is integrally formed with the upper lid portion <NUM> and extends from the upper lid portion <NUM> along an outer circumferential surface of the cylinder main body <NUM>.

The extension portion <NUM> includes a sensor holding portion 44a which bulges outward in a radial direction of the cylinder and holds the sensor <NUM>. That is, it can be said that the sensor holding portion 44a is integrally formed with the cylinder <NUM>.

Description will be made with reference to <FIG>. The spring receiving portion <NUM> can move relative to the outer circumferential surface of the cylinder main body <NUM> along an axis CL1, and is provided to be rotatable around the axis CL1. The spring receiving portion <NUM> includes a cylindrical base portion 33a disposed along the outer circumferential surface of the cylinder main body <NUM>, a spring receiving main body 33b which is a plate-shaped annular portion protruding from the base portion 33a toward an outer side in the radial direction of the cylinder <NUM> and which comes into contact with an upper end of the spring <NUM>, a first flange portion 33c (a protruding portion 33c) which is formed adjacent to the spring receiving main body 33b and of which an outer edge is connected to the sensor <NUM> via a coupling member <NUM> to be described later, and a claw portion 33d which extends downward from a lower end of the base portion 33a and of which a lower end is formed into a claw shape.

A contact member <NUM> which can come into contact with the jack portion <NUM> is fixed to an outer side of an upper end of the base portion 33a. The upper end of the base portion 33a is located above an upper surface of the contact member <NUM>.

The first flange portion 33c is a plate-shaped member formed into an annular shape in a similar manner to the spring receiving main body 33b. A thickness of the first flange portion 33c (a thickness in the axial direction of the cylinder <NUM>. The same applies hereinafter. ) is smaller than a thickness of the spring receiving main body 33b. Therefore, the first flange portion 33c is easily bent in the upper-lower direction.

A seal member <NUM> is attached to the claw portion 33d. The seal member <NUM> is a member for preventing dust from entering between the spring receiving portion <NUM> and the cylinder main body <NUM> (the cylinder <NUM>).

Description will be made with reference to <FIG>. The piston rod <NUM> is provided to be movable along the axis CL1 inside the cylinder main body <NUM>. A downward force is applied to the piston rod <NUM> by the spring <NUM> so as to separate the piston rod <NUM> from the cylinder <NUM>. An upper end of the piston rod <NUM> faces an inner side of the cylinder <NUM>.

The piston <NUM> is configured such that oil can pass through an inner side of the piston <NUM>, and the piston <NUM> is movable in the upper-lower direction in the cylinder main body <NUM> together with the piston rod <NUM>. When the piston <NUM> moves in the upper-lower direction along an inner wall of the cylinder main body <NUM>, oil passes through the inner side of the piston <NUM>, and a damping force is generated.

Description will be made with reference to <FIG>. The jack portion <NUM> is housed in a space formed between the cylinder main body <NUM> and the extension portion <NUM>. The jack portion <NUM> includes a jack housing <NUM> fixed along an inner circumferential surface of the extension portion <NUM>, a plunger <NUM> which is provided in a manner in which the plunger <NUM> can be lifted and lowered along an outer circumferential surface of the cylinder main body <NUM> and of which a lower end comes into contact with an upper surface of the base portion 33a, and a jack chamber <NUM> which is a region surrounded by the jack housing <NUM> and the plunger <NUM> and is filled with oil fed from the pump <NUM> (see <FIG>).

Description will be made with reference to <FIG> as well. The pump <NUM> is a liquid feed pump for feeding oil to the jack chamber <NUM>. The pump <NUM> includes a motor <NUM>, a pump case <NUM> filled with oil, and an adjustment unit <NUM> of which a tip end is positioned at the pump case <NUM> and which can be lifted and lowered by operating the motor <NUM>.

The sensor <NUM> includes a sensor main body <NUM> which is formed into a substantially cylindrical shape and is held by the sensor holding portion 44a, a fixed lid portion <NUM> which is fastened to an inner periphery of the sensor holding portion 44a and prevents the sensor main body <NUM> from coming off, a seal member <NUM> which is provided inside an upper end of the fixed lid portion <NUM> and prevents dust from entering the sensor <NUM>, a sensor outer cylinder portion <NUM> which is positioned below the seal member <NUM> and is fixed along inner circumferential surfaces of the sensor main body <NUM> and the fixed lid portion <NUM>, a bottomed cylindrical sensor inner cylinder portion <NUM> which is provided along an inner circumferential surface of the sensor outer cylinder portion <NUM>, a coil portion <NUM> which is formed of a conductive wire wound around an outer side of the sensor inner cylinder portion <NUM>, a core portion <NUM> which is provided to be movable upward and downward inside the sensor inner cylinder portion <NUM>, a guide portion <NUM> which extends further downward from a lower end of the sensor main body <NUM> and guides a movement of the core portion <NUM> in the upper-lower direction, and a hardness <NUM> of which an outer circumferential surface is held by the seal member <NUM> and which is connected to the control unit <NUM> (see <FIG>).

The sensor main body <NUM> can be inserted into the sensor holding portion 44a from above the sensor holding portion 44a. The sensor main body <NUM> is a member in which an outer diameter of an upper end is larger than an outer diameter of other portions. The upper end of the sensor main body <NUM> is supported by a protruding portion which protrudes inward from an inner circumferential surface of the sensor holding portion 44a, thereby preventing the sensor main body <NUM> from falling downward. An axis CL2 of the sensor main body <NUM> extends parallel to the axis CL1 of the cylinder <NUM>.

A part of an outer circumferential surface of the fixed lid portion <NUM> is formed into a male screw shape, and is fastened to an inner circumferential surface of the sensor holding portion 44a formed into a female screw shape.

The sensor inner cylinder portion <NUM> is fixed to an inner side of the sensor outer cylinder portion <NUM>. Each of an upper end and a lower end of the sensor inner cylinder portion <NUM> protrudes outward in a radial direction of the sensor inner cylinder portion <NUM>, and prevents the coil portion <NUM> from coming off.

The coil portion <NUM> is accommodated in a space formed between the sensor outer cylinder portion <NUM> and the sensor inner cylinder portion <NUM>. The coil portion <NUM> can be energized.

The core portion <NUM> is formed into a substantially columnar shape, and a tip end of the core portion <NUM> is formed into a hemispherical shape. The core portion <NUM> is provided to be movable along the axis CL2. Since the axis CL2 is parallel to the axis CL1, it can be said that the core portion <NUM> is movable along the axis CL1. The coupling member <NUM> coupled to the spring receiving portion <NUM> is formed integrally with the core portion <NUM> at a lower end of the core portion <NUM>.

The coupling member <NUM> includes an enlarged diameter portion <NUM> which is continuously enlarged in diameter from a lower end of the core portion <NUM>, a large diameter portion <NUM> which is continuous from the enlarged diameter portion <NUM> and has a diameter larger than a diameter of the core portion <NUM>, and a first recessed portion <NUM> (a recessed portion <NUM>) which is continuous in a circumferential direction of the large diameter portion <NUM> and is formed into a groove shape. The coupling member <NUM> is formed integrally with the core portion <NUM>, and is a member separate from the spring receiving portion <NUM>.

There is a gap between a bottom surface 103a of the first recessed portion <NUM> and an outer circumferential surface of the spring receiving portion <NUM>.

Description will be made with reference to <FIG> and <FIG>. The guide portion <NUM> is a portion which has a substantially semicircular shape in a bottom view and surrounds an outer circumferential surface of the coupling member <NUM> over a substantially half circumference. The guide portion <NUM> opens toward the cylinder <NUM>. It is preferable that the guide portion <NUM> surrounds a part of the outer circumferential surface of the coupling member <NUM> and a part of the outer circumferential surface of the core portion <NUM>, and opens toward the cylinder <NUM>. The reason will be described later.

Description will be made with reference to <FIG>. The guide portion <NUM> is arranged at distances apart from the spring receiving portion <NUM>. Distances L1 and L2 are smaller than a diameter D of the core portion <NUM>.

Description will be made with reference to <FIG>. The operation unit <NUM> is disposed, for example, at a side of a speedometer so that an occupant can operate the operation unit <NUM> in a riding posture.

A preload adjustment of the shock absorber <NUM> described above will be described.

Description will be made with reference to <FIG> and <FIG>. In the state illustrated in the drawing, an initial load is a smallest load. That is, the spring <NUM> is in a longest state. The occupant can increase the initial load in order to change ride comfort. The occupant operates the operation unit <NUM> to increase the initial load.

The control unit <NUM> which is received an electric signal from the operation unit <NUM> energizes the motor <NUM> to lower the adjustment unit <NUM>. When the adjustment unit <NUM> is lowered, oil in the pump case <NUM> is fed into the jack chamber <NUM>.

Description will be made with reference to <FIG> and <FIG>. The oil fed into the jack chamber <NUM> lowers the plunger <NUM> against a force of the spring <NUM>. When the plunger <NUM> is lowered, the spring receiving portion <NUM> is pushed down, and the spring <NUM> is compressed. Accordingly, the initial load is increased. At this time, the jack housing <NUM> and the cylinder main body <NUM> do not move.

When the spring <NUM> is compressed, the spring receiving portion <NUM> and the core portion <NUM> are also lowered together with the spring receiving portion <NUM>. An electromotive force induced in the coil portion <NUM> changes as the core portion <NUM> is lowered. Accordingly, a position of the spring receiving portion <NUM> in the axial direction of the cylinder <NUM>, that is, a compression amount of the spring <NUM> can be detected.

Description will be made with reference to <FIG> as well. Information related to the position of the spring receiving portion <NUM> detected by the sensor <NUM> is sent to the control unit <NUM> as an electric signal. The control unit <NUM> continues to energize the motor <NUM> until the spring receiving portion <NUM> moves to a predetermined position. When the spring receiving portion <NUM> moves to the predetermined position, the control unit <NUM> ends the energization of the motor <NUM>.

When the initial load is reduced, the control unit <NUM> operates the motor <NUM> so as to raise the adjustment unit <NUM>. When the adjustment unit <NUM> is raised, the plunger <NUM> is pushed up by the force of the spring <NUM>. When the plunger <NUM> is pushed up, oil in the jack chamber <NUM> is fed into the pump case <NUM>. The position of the spring receiving portion <NUM> is detected by the sensor <NUM>.

Description will be made with reference to <FIG> and <FIG>. A load in a twisting direction may be applied to the spring receiving portion <NUM> due to an influence of the spring <NUM> and the like. That is, a force in a rotation direction around the axis CL1 may be applied to the spring receiving portion <NUM>. Since the coupling member <NUM> is provided to allow the rotation of the spring receiving portion <NUM> around the axis CL1, the force in the rotation direction can be released by idling the spring receiving portion <NUM>.

Description will be made with reference to <FIG>. The shock absorber <NUM> includes:.

The coupling member <NUM> is integrally formed with the core portion <NUM>.

With regard to the spring receiving portion <NUM> and the coupling member <NUM>, the coupling member <NUM> is provided with the first recessed portion <NUM>, the spring receiving portion <NUM> is provided with the first flange portion 33c facing the first recessed portion <NUM>, and the spring receiving portion <NUM> and the coupling member <NUM> are coupled to each other via the first recessed portion <NUM> and the first flange portion 33c.

The coupling member <NUM> allows the spring receiving portion <NUM> to rotate around the axis CL1 and allows the core portion <NUM> (the sensor <NUM>) to move along the axial direction. A load may be applied to the spring receiving portion <NUM> such that the spring receiving portion <NUM> is twisted in the circumferential direction of the cylinder <NUM> due to the influence of the spring <NUM> and the like. Since the coupling member <NUM> allows the rotation of the spring receiving portion <NUM> around the axis CL1, the load applied in the twisting direction can be released. Therefore, it is possible to reduce the load which may be applied to the core portion <NUM>. That is, according to the present invention, it is possible to provide the shock absorber <NUM> (the rear cushion <NUM>) which can reduce the load which may be applied to the sensor <NUM>.

Further, the coupling member <NUM> is formed integrally with the core portion <NUM>. Accordingly, the sensor <NUM> can be compactly disposed in the vicinity of the spring receiving portion <NUM>.

Description will be made with reference to <FIG>. The spring receiving portion <NUM> includes the first flange portion 33c formed into an annular shape around the axis CL1.

The coupling member <NUM> includes the first recessed portion <NUM> formed into a recessed shape to surround an outer edge of the first flange portion 33c.

The core portion <NUM> is held by the first flange portion 33c via the first recessed portion <NUM>.

The outer edge of the first flange portion 33c is surrounded by the first recessed portion <NUM>. Accordingly, the rotation of the spring receiving portion <NUM> around the axis CL1 can be allowed with a simple configuration. As a result, it is possible to provide the shock absorber <NUM> which can appropriately displace the core portion <NUM> while preventing a load from being applied to the core portion <NUM>.

The sensor <NUM> is disposed outside the cylinder <NUM>. As compared with the case where the sensor <NUM> is disposed inside the cylinder <NUM>, maintenance of the shock absorber <NUM> can be easily performed. The shock absorber <NUM> can be used for a long period of time by improving maintainability while reducing a load which may be applied to the sensor <NUM>.

The sensor <NUM> further includes the guide portion <NUM> which guides the movement of the core portion <NUM> along the axial direction. Wiring and the like of the sensor <NUM> can be simplified by arranging the coil portion <NUM> at a fixed side and arranging the core portion <NUM> at a moving side. Since the guide portion <NUM> is provided, the core portion <NUM> can be more reliably moved parallel to the axis CL1. Accordingly, it is possible to provide the shock absorber <NUM> which can improve the accuracy of position information to be detected.

Further, the core portion <NUM> has a circular cross-sectional shape whose normal direction is the axial direction of the core portion <NUM>. Accordingly, the rotation of the spring receiving portion <NUM> around the axis CL1 is easily allowed. As a result, it is possible to provide the shock absorber <NUM> which easily reduces a load which may be applied to the core portion <NUM>.

Description will be made with reference to <FIG>. The core portion <NUM> is disposed between the guide portion <NUM> and the cylinder <NUM>. Accordingly, the core portion <NUM> can be protected against flying stones, mud, and the like. As a result, it is possible to provide the shock absorber <NUM> which can further improve the protection performance of the sensor <NUM>, in addition to the above effects.

Furthermore, the guide portion <NUM> is disposed at distances apart from the spring receiving portion <NUM>, and the distances L1 and L2 are smaller than the diameter D of the core portion <NUM> in the radial direction of the cylinder <NUM>.

Accordingly, it is possible to provide the shock absorber <NUM> in which the core portion <NUM> can be prevented from falling off from between the spring receiving portion <NUM> at the main body side and the guide portion <NUM>, in addition to the above effects.

Next, a rear cushion (a shock absorber) according to a second embodiment will be described with reference to the drawings.

<FIG> illustrates a main part of a rear cushion 20A (hereinafter, may be referred to as a "shock absorber 20A") according to the second embodiment. The shock absorber 20A is different from the shock absorber <NUM> (see <FIG>) in a position where a guide portion 98A is disposed. Other basic configurations are the same as those of the shock absorber <NUM>. Components common to those of the shock absorber <NUM> will be denoted by the same reference numerals, and detailed description thereof will be omitted.

A sensor 90A constituting an adjustment unit 60A has a substantially semicircular guide portion 98A which guides the core portion <NUM>. The guide portion 98A opens parallel to the cylinder <NUM>.

The rear cushion 20A having the configuration described above also achieves the predetermined effects of the present invention.

Next, a rear cushion (shock absorber) according to a third embodiment will be described with reference to the drawings.

<FIG> illustrates a main part of a rear cushion 20B (hereinafter, may be referred to as a "shock absorber 20B") according to the third embodiment. The shock absorber 20B is different from the shock absorber <NUM> (see <FIG>) in that the shock absorber 20B does not include the guide portion <NUM> (see <FIG>). Other basic configurations are the same as those of the shock absorber <NUM>. Components common to those of the shock absorber <NUM> will be denoted by the same reference numerals, and detailed description thereof will be omitted.

A sensor 90B constituting an adjustment unit 60B does not include a guide portion (see reference numeral <NUM> in <FIG>) which guides the core portion <NUM>.

The shock absorber 20B having the configuration described above also achieves the predetermined effects of the present invention.

Next, a rear cushion (shock absorber) according to a fourth embodiment will be described with reference to the drawings.

<FIG> illustrates a main part of a rear cushion 20C (hereinafter, may be referred to as a "shock absorber 20C") according to the fourth embodiment. A basic configuration of the rear cushion 20C is the same as that of the shock absorber <NUM>. Components common to those of the shock absorber <NUM> will be denoted by the same reference numerals, and detailed description thereof will be omitted.

The rear cushion 20C includes a spring receiving portion <NUM> (a receiving member <NUM>) which receives the spring <NUM>, an adjustment unit 60C which adjusts a preload, and a coupling member <NUM> which couples the spring receiving portion <NUM> and a sensor 90C of the adjustment unit 60C.

The spring receiving portion <NUM> is movable along the axis CL1 relative to an outer circumferential surface of the cylinder main body <NUM>, and is provided to be rotatable around the axis CL1. The spring receiving portion <NUM> includes a cylindrical base portion 133a disposed along the outer circumferential surface of the cylinder main body <NUM>, a spring receiving main body 133b which is a plate-shaped annular portion protruding from the base portion 133a toward an outer side in the radial direction of the cylinder <NUM> and which comes into contact with an upper end of the spring <NUM>, a second recessed portion 133c (a recessed portion 133c) which is formed on an outer periphery of the spring receiving main body 133b and is recessed toward the axis CL1, and a claw portion 133d which extends downward from a lower end of the base portion 133a and of which a lower end is formed into a claw shape.

The adjustment unit 60C includes the sensor 90C which detects a position of the spring receiving portion <NUM>. The sensor 90C includes a guide portion 98C which guides the core portion <NUM>. A position and the like where the guide portion 98C is disposed are the same as those of the guide portion <NUM> described above (see <FIG>), and detailed description thereof will be omitted.

The coupling member <NUM> includes an enlarged diameter portion <NUM> which is continuously enlarged in diameter from a lower end of the core portion <NUM>, a large diameter portion <NUM> which is continuous from the enlarged diameter portion <NUM> and has a diameter larger than the diameter of the core portion <NUM>, and a second flange portion <NUM> (a protruding portion <NUM>) which is formed so as to continuously protrude in a circumferential direction of the large diameter portion <NUM>. The coupling member <NUM> is formed integrally with the core portion <NUM>, and is a member separate from the spring receiving portion <NUM>.

There is a small gap between the second flange portion <NUM> and the second recessed portion 133c, which allows members to rotate relative to each other.

The shock absorber 20C having the configuration described above also achieves the predetermined effects of the present invention.

Further, the spring receiving portion <NUM> includes the second recessed portion 133c over a circumferential direction, and the second recessed portion 133c is formed into a recessed shape toward a center of the spring receiving portion <NUM> on an outer circumferential edge of the spring receiving portion <NUM>.

The coupling member <NUM> includes the second flange portion <NUM> which protrudes toward the second recessed portion 133c and of which a tip end faces the second recessed portion 133c.

The core portion <NUM> is held by the second recessed portion 133c via the second flange portion <NUM>.

In the shock absorber 20C, the second flange portion <NUM> extends to the second recessed portion 133c. Accordingly, the rotation of the spring receiving portion <NUM> around the axis CL1 can be allowed with a simple configuration. As a result, it is possible to provide the shock absorber 20C which can appropriately displace the core portion <NUM> while preventing a load from being applied to the core portion <NUM>.

Although a case where the shock absorber according to the present invention is applied to a twin-shock type rear cushion has been described in the embodiments described above, the shock absorber according to the present invention is not limited to such examples. The shock absorber according to the present invention is also applicable to a mono-shock type rear cushion, an inverted front fork, and an upright front fork. That is, the shock absorber according to the present invention is not limited to the twin-shock type rear cushion.

Furthermore, the shock absorber according to the present invention is applicable not only to a two-wheel vehicle but also to a three-wheel vehicle, a buggy, and the like. That is, the present invention can be mounted on a straddle type vehicle other than a two-wheel vehicle.

In the shock absorber according to the present invention, the core portion <NUM> and the coupling members <NUM> and <NUM> may be configured to be rotatable around the axis CL2.

The present invention is not limited to the embodiments, the scope of protection being defined by the appended claims.

Claim 1:
A shock absorber (<NUM>, 20A, 20B, 20C) comprising:
a cylinder (<NUM>) provided with a piston (<NUM>) which is movable along an axis (CL1) inside the cylinder (<NUM>);
a spring (<NUM>) provided coaxially with the cylinder (<NUM>);
a receiving member (<NUM>, <NUM>) receiving the spring (<NUM>) and provided to be movable in an axial direction of the cylinder (<NUM>);
a sensor (<NUM>, 90A, 90B, 90C) configured to detect a position of the receiving member (<NUM>, <NUM>); and
a coupling member (<NUM>, <NUM>) coupling the receiving member (<NUM>, <NUM>) and the sensor (<NUM>, 90A, 90B, 90C), allowing rotation of the receiving member (<NUM>, <NUM>) around the axis (CL1), and allowing a movement of the sensor (<NUM>, 90A, 90B, 90C) along the axial direction, characterized in that:
the sensor (<NUM>, 90A, 90B, 90C) includes
a coil portion (<NUM>) formed by winding a conductive wire, a movement of the coil portion (<NUM>) being restricted, and
a core portion (<NUM>) being movable along the axis (CL1) together with the coupling member (<NUM>, <NUM>), at least a part of the core portion (<NUM>) facing an inner side of the coil portion (<NUM>);
the coupling member (<NUM>, <NUM>) is formed integrally with the core portion (<NUM>); and
a recessed portion (<NUM>, 133c) is formed in one of the receiving member (<NUM>, <NUM>) and the coupling member (<NUM>, <NUM>), a protruding portion (33c, <NUM>) facing the recessed portion (<NUM>, 133c) is formed in the other one of the receiving member (<NUM>, <NUM>) and the coupling member (<NUM>, <NUM>), and the receiving member (<NUM>, <NUM>) and the coupling member (<NUM>, <NUM>) are coupled to each other via the recessed portion (<NUM>, 133c) and the protruding portion (33c).