JP2007009993A - Front fork of riding type vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To miniaturize a vehicle by shortening the length of a front fork. <P>SOLUTION: This vehicle is provided with the front fork 4 which is extended by facing the vertical direction, whose upper end part is supported on a vehicle body frame 2 side, and whose lower end part supports an axle 5 of a front wheel 6. The front fork 4 is provided with a damper tube 16 extending by facing the vertical direction, an axle bracket 17 attached to a lower end part of the damper tube 16 to support the axle 5, a piston 20 supported on the vehicle body frame 2 side and fitted into the damper tube 16 so as to slide in the axial direction to partition pressure oil chambers 18, 19 in the damper tube 16, and a damping force generating part 30 for regulating flow of pressure oil between a pressure oil chamber 19 and an oil storage chamber 24 in the outside of the pressure oil chamber 19 to generate damping force and change degree of damping force. The damping force generating part 30 is attached to the axle bracket 17 in the outside of the damper tube 16. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a front fork of a straddle-type vehicle provided with a damping force generator that makes the magnitude of damping force variable.

  Conventionally, the above-mentioned front fork is disclosed in Patent Document 1 below. According to this publication, the motorcycle includes a front fork whose upper end is supported by the vehicle body frame and whose lower end supports the axle of the front wheel.

  The front fork extends in a vertical direction, and a lower end side thereof is supported by a damper tube that supports the axle, a piston rod is supported on the body frame side, and is fitted into the damper tube so as to be slidable in an axial direction. The pressure oil is caused to flow between the piston that partitions the pressure oil chamber in the damper tube into upper and lower pressure oil chambers, and between the lower pressure oil chamber and the oil storage chamber outside the lower pressure oil chamber. And a damping force generator that regulates the flow of oil and generates a damping force.

  The damping force generating portion includes a case constituting the outer shell, a first oil chamber that is fitted into the internal oil chamber of the case and communicates with the oil storage chamber, and a lower pressure oil chamber. A main body section that is partitioned into a second oil chamber that communicates with each other and that has first and second oil passages that communicate with the first and second oil chambers individually, and is attached to the main body section. A low-speed damping valve capable of adjusting the opening degree of the first oil passage, and attached to the main body part, from the second oil chamber on the lower pressure oil chamber side toward the first oil chamber on the oil storage chamber side. A high-speed damping valve that opens and closes the second oil passage in accordance with the pressure when the pressure of the pressure oil flowing through the second oil passage is equal to or higher than a predetermined value, and adjusts the predetermined value; Yes.

  A cylindrical operation member is supported by the opening of the internal oil chamber of the case so as to be rotatable only about its axis. The main body is screwed onto the operation member. The main body can be moved relative to the case by twisting the operating member, and the predetermined value of the pressure can be adjusted by the relative movement.

  When the main body is moved forward with respect to the inside of the case by twisting of the operation member, the predetermined value is decreased, and when the main body is moved backward, the predetermined value is increased. It is supposed to be.

  When an impact force is applied to the shock absorber from the traveling surface via the front wheel and the axle during traveling of the vehicle, the damper tube and the piston move relative to each other, and the shock absorber attempts to contract. Then, first, the pressure oil in the lower pressure oil chamber of the damper tube is introduced into the second oil chamber.

  At the beginning of the contraction operation of the shock absorber or when the impact force is small, the contraction operation is slow, so that the pressure oil that has reached the second oil chamber is first slow-damped with the first oil passage. The oil flows through the valve to the first oil chamber and from there to the oil storage chamber. The flow of the pressure oil is restricted by the low-speed damping valve, and a damping force is generated by this restriction, and the impact force during the contracting operation is alleviated.

  Further, when the operation of the shock absorber is accelerated, for example, when the operation becomes high speed, the pressure oil in the second oil chamber flows in addition to the flow through the low speed damping valve, and the second oil path and the high speed damping valve. Through the first oil chamber. The flow of the pressure oil is restricted by the high-speed damping valve, and by each restriction, a larger damping force is generated, and the impact force during the contracting operation is more reliably mitigated.

  Here, if the opening of the first oil passage is adjusted by operating the low speed damping valve, and if the predetermined value of the pressure in the high speed damping valve is adjusted by twisting the operating member, the damping force The size is adjusted to the desired value.

  The case includes a lower end portion of the damper tube and an axle bracket, and the main body portion of the damping force generation unit, the low speed damping valve, and the high speed damping valve are provided in a pressure oil chamber in the damper tube. ing.

JP-A-8-159202

  By the way, as described above, the main body of the damping force generation unit, the low speed damping valve, and the high speed damping valve are provided in the pressure oil chamber in the damper tube. That is, the damper tube and the damping force generator in the front fork are arranged in a vertical direction. For this reason, the length of the front fork tends to be excessive, and thus the vehicle may become large.

  The damping force generator includes an operation member in addition to the case, the main body, and the low and high speed damping valves. For this reason, there is a problem that the number of parts of the front fork is large and the configuration thereof is complicated.

  The operation member is generally screwed into the case by a right-hand screw. For this reason, when the operation member is twisted clockwise (or counterclockwise), the main body moves forward (or backwards) with respect to the inside of the case, and the predetermined value becomes small (or large). In other words, the damping force is reduced (or increased).

  However, when the operation member is twisted clockwise (or counterclockwise), it is considered that a large (or small) damping force can be obtained as a general operation feeling. For this reason, when it is going to obtain desired damping force, there exists a possibility of operating the said operation member accidentally.

  The present invention has been made paying attention to the above situation, and an object of the present invention is to shorten the length of the front fork and make the vehicle compact.

  Another object of the present invention is to make the front fork simpler and to prevent errors in the operation of the front fork to obtain a desired magnitude of damping force. Is to do.

The invention of claim 1 is a damper tube 16 that extends in the vertical direction, an axle bracket 17 that is attached to the lower end of the damper tube 16 and supports the axle 5 of the front wheel 6, and is supported on the vehicle body frame 2 side. A piston 20 that is slidably fitted in the damper tube 16 in the axial direction and partitions the pressure oil chambers 18 and 19 in the damper tube 16, the pressure oil chamber 19, and an oil storage chamber outside the pressure oil chamber 19. A front fork of a saddle-ride type vehicle including a damping force generation unit 30 that generates a damping force by restricting the flow of pressure oil between the damping force and a variable amount of the damping force,
The damping force generator 30 is attached to the axle bracket 17 outside the damper tube 16.

According to a second aspect of the present invention, in addition to the first aspect of the present invention, the damping force generating portion 30 is fitted into a case 31 constituting the outer shell and an internal oil chamber 33 of the case 31, and the internal oil chamber. 33 is divided into a first oil chamber 38 communicating with the oil storage chamber 24, and a second oil chamber 39 communicating with the pressure oil chamber 19, and the first oil chamber 38 and the second oil chamber 39 are separated from each other. A main body portion 40 formed with first and second oil passages 43 and 44 that communicate with each other individually, and a low-speed damping valve 48 attached to the main body portion 40 and capable of adjusting the opening degree of the first oil chamber 38. When the pressure of the pressure oil that is attached to the main body portion 40 and flows through the second oil passage 44 from the pressure oil chamber 19 toward the oil storage chamber 24 is equal to or greater than a predetermined value, the second oil passage 44 is A high-speed damping valve 5 that can be opened and closed in accordance with the pressure and can adjust the predetermined value. In the front fork of the straddle type vehicle including bets,
The predetermined value can be adjusted by screwing the main body 40 into the case 31 and moving the main body 40 relative to the case 31 by twisting.

According to a third aspect of the present invention, in addition to the second aspect of the invention, when the main body 40 is moved forward C with respect to the inside of the case 31 by twisting of the main body 40, the predetermined value is small. In the front fork of the saddle-ride type vehicle in which the predetermined value is increased when the main body 40 is moved backward D,
The main body 40 is screwed to the case 31 with a left screw 59.

  In this section, the reference numerals appended to the above terms are not to be construed as limiting the technical scope of the present invention to the section “Example” described later or the contents of the drawings.

  The effects of the present invention are as follows.

According to the first aspect of the present invention, there is provided a damper tube that extends in the vertical direction, an axle bracket that is attached to a lower end portion of the damper tube and supports the axle of the front wheel, is supported on the vehicle body frame side, and is axially supported by the damper tube. A damping force that regulates the flow of pressure oil between the piston that is slidably inserted and partitions the pressure oil chamber in the damper tube, and the pressure oil chamber and the oil storage chamber outside the pressure oil chamber. In a front fork of a saddle-ride type vehicle provided with a damping force generation unit that generates the damping force and makes the magnitude of the damping force variable,
The damping force generator is attached to the axle bracket outside the damper tube.

  For this reason, the damper tube and the damping force generator can be arranged in parallel. Therefore, the length of the front fork can be shortened as compared with the case where the damper tube and the damping force generating portion in the front fork are arranged in the vertical direction as in the prior art. As a result, the vehicle can be made compact.

The invention of claim 2 includes a case in which the damping force generating portion constitutes an outer shell thereof, a first oil chamber that is fitted into an internal oil chamber of the case and communicates the internal oil chamber with the oil storage chamber, And a main body portion that is partitioned into a second oil chamber that communicates with the pressure oil chamber, and that includes first and second oil passages that individually communicate the first oil chamber and the second oil chamber; A low-speed damping valve attached to the main body and capable of adjusting the opening of the first oil chamber, and attached to the main body and flows through the second oil passage from the pressure oil chamber toward the oil storage chamber. A front fork of a straddle-type vehicle provided with a high-speed damping valve that opens and closes the second oil passage according to the pressure when the pressure oil pressure is equal to or higher than the predetermined value, and adjusts the predetermined value. In
The predetermined value can be adjusted by screwing the main body into the case and moving the main body relative to the case by twisting the main body.

  That is, the main body provided with the damping valve is directly screwed into the case without providing an operation member as in the prior art, and the predetermined value is adjusted by twisting the main body. Accordingly, the magnitude of the damping force is variable.

  For this reason, it is sufficient that the damping force generation unit includes the case, the main body, and the low and high speed damping valve, and a separate operation is performed for adjusting the setting of the predetermined value in the damping valve as in the related art. It is not necessary to provide a member. Therefore, the number of parts of the front fork can be reduced, and the configuration can be simplified.

According to a third aspect of the present invention, when the main body is moved forward relative to the inside of the case by twisting of the main body, the predetermined value is decreased, and when the main body is moved backward, In the front fork of the saddle riding type vehicle in which the predetermined value is increased,
The main body is screwed into the case with a left-hand screw.

  For this reason, when the main body is twisted clockwise (or counterclockwise), the main body moves backward (or forward) with respect to the inside of the case, and the predetermined value increases (or decreases). That is, the damping force is increased (or decreased).

  Therefore, the damping force can be increased (or decreased) by twisting the main body clockwise (or counterclockwise), which matches a general operation feeling. As a result, it is possible to prevent an error from occurring in the operation of the front fork in order to obtain a damping force having a desired magnitude.

  The best mode for carrying out the present invention in order to achieve the object of shortening the length of the front fork and making the vehicle compact is as follows. That's right.

  That is, a front fork is provided that extends vertically and has an upper end supported on the body frame side and a lower end supported on the axle of the front wheel. The front fork includes a damper tube that extends in the vertical direction, an axle bracket that is attached to a lower end portion of the damper tube and supports the axle, and is supported on the vehicle body frame side, and is relatively relative to the damper tube in the axial direction. A damping force that regulates the flow of pressure oil between the piston that is slidably inserted and partitions the pressure oil chamber in the damper tube, and the pressure oil chamber and the oil storage chamber outside the pressure oil chamber. And a damping force generator that makes the magnitude of the damping force variable. The damping force generator is attached to the axle bracket outside the damper tube.

  In order to explain the present invention in more detail, an embodiment thereof will be described with reference to the accompanying drawings.

  2 and 3, reference numeral 1 denotes a straddle-type vehicle exemplified as a motorcycle. An arrow Fr indicates the front of the vehicle 1 in the traveling direction.

  The vehicle 1 includes a body frame 2, a front fork 4 that is steerably supported by a head pipe 3 of the body frame 2, a front wheel 6 that is supported on the front fork 4 by an axle 5, and the front fork. 4, a resin-made front fender 7 that covers the front wheel 6 from above, and a disc brake 8 that can brake the front wheel 6. The vehicle 1 is allowed to travel with its front wheels 6 and rear wheels (not shown) grounded on the traveling surface 9.

  The front fork 4 is inserted into the head pipe 3 and supported by a steering shaft (not shown) that is rotatably supported around the axis 10 of the head pipe 3, and is supported on the upper and lower ends of the steering shaft. Upper and lower brackets 11 and 12 and a pair of left and right shock absorbers that extend in a longitudinal direction parallel to the shaft center 10 and are supported across the upper and lower brackets 11 and 12 and that support the axle 5 13.

  The shock absorber 13 includes a damper tube 16 that extends in the vertical direction, a cast axle bracket 17 that is supported by the lower end portion of the damper tube 16 and supports the axle 5, and an axial direction in the damper tube 16. A piston 20 that is inserted so as to be relatively slidable and partitions the pressure oil chamber in the damper tube 16 into upper and lower pressure oil chambers 18 and 19 and extends vertically, and its upper end is on the vehicle body frame 2 side. The piston rod 21 is supported by the upper and lower brackets 11 and 12 and is connected to the piston 20 at the lower end.

  The shock absorber 13 includes an outer tube 23 that is fitted onto the damper tube 16, an upper end portion is coupled to the upper end portion of the damper tube 16, and a lower end portion that supports the axle bracket 17. An oil storage chamber 24 is formed in the lower portion between the damper tube 16 and the outer tube 23, and a gas chamber 25 filled with gas is formed in the upper portion. The oil storage chamber 24 and the gas chamber 25 are located outside the pressure oil chambers 18 and 19.

  Further, the shock absorber 13 is fitted to the upper portion of the damper tube 16 and the piston rod 21 and is coupled to the upper end portion of the piston rod 21, and is fitted to the cover tube 26. A spring 27 that biases the damper tube 16 and the cover tube 26 apart from each other is provided. In the shock absorber 13, the damper tube 16 and the piston 20 are moved relative to each other while being opposed to the spring 27 so that the contraction operation A is possible. On the other hand, the shock absorber 13 can be extended by the relative movement of the damper tube 16 and the piston 20 by the urging force of the spring 27.

  The shock absorber 13 includes a damping valve 29 provided on the piston 20. When the damper tube 16 and the piston 20 move relative to each other and the damper 13 performs the contraction operation A or the expansion operation B, the damping valve 29 is one of the pressure oil chambers 18 and 19. The pressure oil flows from the pressure oil chamber toward the other pressure oil chamber so as to penetrate the piston 20, and the flow of the pressure oil is restricted to generate a damping force.

  The shock absorber 13 regulates the flow of the pressure oil when the pressure oil flows between the lower pressure oil chamber 19 and the oil storage chamber 24 during the contraction operation A or the extension operation B. A damping force generating unit 30 that generates a damping force and makes the magnitude of the damping force variable is provided. The damping force generator 30 is disposed in the vicinity of the damper tube 16 outside the front of the damper tube 16 and is attached to the axle bracket 17.

  In FIG. 1, the damping force generator 30 includes a case 31 that constitutes an outer shell thereof and is supported by the damper tube 16 via the axle bracket 17. The case 31 includes a case body 32 that is integrally formed with the axle bracket 17 by casting outside the damper tube 16. An internal oil chamber 33 of the case main body 32 extends vertically and has a bottom, and an opening 34 that opens outward is formed at an upper end portion thereof. An annular cap 35 is detachably fixed to the opening 34 by screwing.

  The damping force generator 30 includes a main body 40 that is removably fitted into the internal oil chamber 33 of the case 31 and divides the internal oil chamber 33 into a first oil chamber 38 and a second oil chamber 39. ing. The upper pressure oil chamber 18 and the oil storage chamber 24 communicate with each other by a first communication passage 41 formed in the axle bracket 17, and the lower pressure oil is transmitted by a second communication passage 42 formed in the axle bracket 17. The chamber 19 and the second oil chamber 39 are communicated with each other. The main body portion 40 is formed with first to third oil passages 43-45 for individually communicating the first oil chamber 38 and the second oil chamber 39 with each other.

  A low-speed damping valve 48 that is attached to the main body 40 and that allows the opening of the first oil passage 43 to be adjusted is provided. A portion 49 of the main body 40 passes through the inner hole of the cap 35 and is exposed to the outside of the case 31. The low-speed damping valve 48 includes a needle valve 51 that is screwed into a portion 49 of the main body 40 with a right screw 50, and an operation portion 52 for twisting the needle valve 51 is disposed outside the case 31. It is exposed to

  A high-speed damping valve 55 attached to the main body 40 is provided. When the pressure of the pressure oil flowing through the second oil passage 44 from the second oil chamber 39 toward the first oil chamber 38 is greater than or equal to a predetermined value, the high-speed damping valve 55 has an opening degree corresponding to the pressure. Thus, the second oil passage 44 is opened so as to be opened and closed, and the flow of pressure oil is restricted, and the predetermined value can be increased or decreased. The high-speed damping valve 55 includes a leaf valve 56 that allows pressure oil to flow only through the second oil passage 44 from the second oil chamber 39 toward the first oil chamber 38, and the cap 35 of the case 31. A spring 57 is provided between the leaf valve 56 and elastically biasing the leaf valve 56 so as to close the second oil passage 44.

  The main body 40 is screwed onto the inner peripheral surface of the cap 35 of the case 31 with a left screw 59. An operation portion 60 for twisting the main body portion 40 is formed in a part 49 of the main body portion 40 and is exposed to the outside above the case 31. The right screw 50, the left screw 59, and the operation units 52 and 60 are located on the same axis 61.

  When the main body 40 is moved relative to the case 31 by a counterclockwise twist and the main body 40 is moved forward C with respect to the inside of the case 31, the spring 57 is attached to the leaf valve 56. The power is reduced and the predetermined value is reduced. On the other hand, when the main body 40 is moved backward D by its clockwise twist, the urging force of the spring 57 is increased and the predetermined value is increased. That is, the predetermined value can be adjusted by changing the urging force of the spring 57 by the relative movement of the main body 40 to the case 31.

  Another damping valve 63 attached to the main body 40 is provided. When the pressure of the pressure oil flowing through the third oil passage 45 from the first oil chamber 38 toward the second oil chamber 39 is equal to or greater than a predetermined value, the other damping valve 63 has an opening degree corresponding to the pressure. The third oil passage 45 is opened so as to be open and closed to restrict the flow of pressure oil. The other damping valve 63 includes a leaf valve 64 that allows pressure oil to flow only through the third oil passage 45 from the first oil chamber 38 toward the second oil chamber 39, and the third oil passage 45. And a spring 65 that elastically biases the leaf valve 64 so as to close the valve.

  The cap 35, the main body 40, the low speed damping valve 48, the high speed damping valve 55, and the other damping valve 63 are detachably fitted into the internal oil chamber 33 of the case body 32 so as to be detachable. The case main body 32 is fixed.

  When the vehicle 1 is traveling, if an impact force is applied from the traveling surface 9 to the shock absorber 13 via the front wheel 6 and the axle 5, the damper tube 16 and the piston 20 are relatively moved against the spring 27. The shock absorber 13 tries to perform the contracting operation A. Then, the pressure oil in the lower pressure oil chamber 19 of the damper tube 16 is introduced into the second oil chamber 39 of the damping force generator 30 through the second communication passage 42.

  At the beginning of the contraction operation A of the shock absorber 13 or when the impact force is small, since the contraction operation A is low speed, the pressure oil that has reached the second oil chamber 39 is the first oil first. The fluid passes through the passage 43 and the low-speed damping valve 48 and flows into the first oil chamber 38, and from there, it flows through the first communication passage 41 to the oil storage chamber 24 (arrow E). The flow of the pressure oil is restricted by the low-speed damping valve 48, and a damping force is generated by this restriction, so that the impact force during the contracting operation A is relieved.

  Further, when the contraction operation A of the shock absorber 13 proceeds, for example, when this operation becomes high speed, the pressure oil in the second oil chamber 39 is added to the flow through the low speed damping valve 48 and the second oil passage. 44 and the high-speed damping valve 55, the fluid flows into the first oil chamber 38 (arrow F). Then, the flow of the pressure oil is restricted by the high speed damping valve 55, and by each restriction, a larger damping force is generated, and the impact force during the contracting operation A is more reliably mitigated.

  Here, if the opening degree of the first oil passage 43 is adjusted by operating the needle valve 51 of the low-speed damping valve 48, and the opening degree is increased or decreased, the magnitude of the damping force is In FIG. 4, it can be adjusted to be smaller or larger as indicated by the solid line from the alternate long and short dash line.

  As shown in FIG. 4, the damping force during the contraction operation A of the shock absorber 13 increases as the operation speed increases. The inclination of the increase in the damping force changes the adjustment amount of the low-speed damping valve 48. But it is almost the same.

  Further, by twisting the main body 40 with respect to the high-speed damping valve 55, if the predetermined value of the pressure oil pressure when the second oil passage 44 is opened is increased or decreased, the damping is achieved. The magnitude of the force can be increased or decreased as shown by the alternate long and short dash line from the solid line in FIG.

  As shown in FIG. 5, the damping force during the contraction operation A of the shock absorber 13 increases as the operation speed increases. The inclination of the increase in the damping force is greater than the predetermined value in the high-speed damping valve 55. The bigger it gets, the bigger it gets.

  On the other hand, when the shock absorber 13 is extended by the impact force B, the lower pressure oil chamber 19 in the damper tube 16 becomes negative pressure. Therefore, first, the oil in the oil storage chamber 24 flows into the first communication path. 41 flows into the first oil chamber 38, flows from here through the third oil passage 45 and the other damping valve 63 to the second oil chamber 39, and further passes through the second communication passage 42 from here. The fluid is caused to flow into the lower pressure oil chamber 19 (Fig. G). And the flow of this oil is regulated by the other damping valve 63, and a damping force is generated by this regulation, and the impact force during the extension operation B is relaxed (solid line in FIGS. 4 and 5).

  According to the above configuration, the damping force generator 30 is attached to the axle bracket 17 outside the damper tube 16.

  For this reason, the damper tube 16 and the damping force generator 30 can be arranged side by side. Therefore, the length of the front fork 4 can be shortened as compared to the case in which the damper tube 16 and the damping force generating portion 30 in the shock absorber 13 of the front fork 4 are arranged in the vertical direction as in the prior art. As a result, the vehicle 1 can be made compact.

  Further, as described above, the predetermined value can be adjusted by screwing the main body portion 40 into the case 31 and moving the main body portion 40 relative to the case 31 by its twisting.

  That is, the main body 40 provided with the low and high speed damping valves 48 and 55 is directly screwed into the case 31 without providing an operation member as in the prior art. The predetermined value can be adjusted by twisting, whereby the magnitude of the damping force is variable.

  For this reason, the damping force generating unit 30 in the shock absorber 13 is sufficient to include the case 31, the main body 40, the low speed damping valve 48, and the high speed damping valve 55, and in the high speed damping valve 55 as in the prior art. It is not necessary to provide a separate operation member for adjusting the setting of the predetermined value. Therefore, the number of parts of the shock absorber 13 of the front fork 4 can be reduced, and the configuration can be simplified.

  Further, as described above, when the main body 40 is moved forward C with respect to the inner side of the case 31 by twisting of the main body 40, the predetermined value becomes smaller and the main body 40 is moved backward D. In this case, in the shock absorber in which the predetermined value is increased, the main body portion 40 is screwed into the case 31 by the left screw 59.

  For this reason, when the main body 40 is twisted clockwise (or counterclockwise), the main body 40 moves backward (or forward) C with respect to the inside of the case 31, and the predetermined value is It is increased (or decreased), that is, the damping force is increased (or decreased).

  Therefore, the damping force can be increased (or decreased) by twisting the main body 40 clockwise (or counterclockwise), which matches a general operation feeling. As a result, it is possible to prevent an error from occurring in the operation of the front fork 4 to the shock absorber 13 in order to obtain a desired magnitude of damping force.

  The damping force generation unit 30 is disposed near the front of the damper tube 16 and includes an operation unit 52 of the low speed damping valve 48 and a high speed damping valve 55 for twisting the main body 40. The operation unit 60 is exposed to the outside above the case 31.

  For this reason, the operation to each of the operation parts 52 and 60 can be easily performed without being obstructed by the damper tube 16 using a wide space in front of the vehicle 1 as a work space. That is, it is possible to easily adjust the magnitude of the damping force in the shock absorber 13 of the front fork 4.

  Although the above is based on the illustrated example, the front fork 4 may be applied to a straddle-type vehicle such as a tricycle.

FIG. 4 is a partially enlarged sectional view of FIG. 3. It is a front side view of a vehicle. FIG. 3 is a partially enlarged sectional view of FIG. 2. It is a damping-force characteristic figure when adjusting a low speed damping valve. It is a damping-force characteristic figure when adjusting a high-speed damping valve.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vehicle 2 Body frame 4 Front fork 5 Axle 6 Front wheel 13 Shock absorber 16 Damper tube 17 Axle bracket 18 Pressure oil chamber 19 Pressure oil chamber 20 Piston 21 Piston rod 23 Outer tube 24 Oil storage chamber 25 Gas chamber 30 Damping force generating part 31 Case 32 Case body 33 Internal oil chamber 34 Opening 35 Cap 38 First oil chamber 39 Second oil chamber 40 Main body portion 43 First oil passage 44 Second oil passage 48 Low speed damping valve 49 Partial 51 Needle valve 52 Operation portion 55 High speed damping Valve 59 Left-hand thread 60 Operation section 61 Axis center A Contraction operation B Extension operation C Forward movement D Reverse movement

Claims (3)

A damper tube that extends vertically, an axle bracket that is attached to the lower end of the damper tube and supports the axle of the front wheel, is supported on the vehicle body frame side, and is slidably fitted in the damper tube in the axial direction. The pressure oil flowing between the piston partitioning the pressure oil chamber in the damper tube, and the pressure oil chamber and the oil storage chamber outside the pressure oil chamber is regulated to generate a damping force; and In a front fork of a saddle-ride type vehicle provided with a damping force generating unit that makes the magnitude of damping force variable,
A front fork of a saddle-ride type vehicle, wherein the damping force generating portion is attached to the axle bracket outside the damper tube. The damping force generating part is connected to a case constituting the outer shell, a first oil chamber that is fitted into the internal oil chamber of the case and communicates with the oil storage chamber, and the pressure oil chamber. A main body portion that is partitioned into a second oil chamber and that has first and second oil passages that communicate the first oil chamber and the second oil chamber with each other, and is attached to the main body portion. A low speed damping valve capable of adjusting the opening degree of the first oil chamber, and a pressure oil pressure attached to the main body portion and flowing in the second oil passage from the pressure oil chamber toward the oil storage chamber has a predetermined value. At the time of the above, in the front fork of the saddle-ride type vehicle provided with the high-speed damping valve that opens the second oil passage according to the pressure and that can adjust the predetermined value,
The saddle riding according to claim 1, wherein the predetermined value can be adjusted by screwing the main body into the case and moving the main body relative to the case by twisting the main body. Type vehicle front fork. When the main body is moved forward relative to the inside of the case by twisting the main body, the predetermined value is decreased, and when the main body is moved backward, the predetermined value is increased. In the front fork of a saddle-ride type vehicle,
The front fork of a straddle-type vehicle according to claim 2, wherein the main body is screwed into the case with a left-hand thread.

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