JP2008143355A - Steering damper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a front wheel from being shaken by shimmy or the like, and not to feel uncomfortable when steering a steering wheel to the same angle to the left and right so as not to feel a difference in feeling.
SOLUTION: An outer cylinder 1 whose both ends are sealed with bearing members 11 and 12, an inner cylinder 3 disposed in an axial core portion of the outer cylinder 1, and an inner cylinder while penetrating the bearing members 11 and 12. 3 and a piston body 4 held by the rod body 2 and defining two oil chambers R1, R2 in the inner cylinder 3, and two oil chambers R1, In a steering damper in which an outer cylinder 1 is formed with an attenuation portion disposed in a main passage communicating with R2, a damping valve 6 that allows passage of hydraulic oil while having two attenuation portions (V1, V2) and Each of the check valves 5 directs the hydraulic oil from the oil chamber to the selected damping valve 6 while preventing the reverse flow, and the damping valve 6 enables adjustment of the generated damping force level by an external operation.
[Selection] Figure 1

Description

  The present invention relates to a steering damper, and more particularly, to an improvement in a steering damper that suppresses vibrations such as shimmy on a front wheel of a motorcycle that is mounted on a front wheel side of a motorcycle and is traveling.

  There have been various proposals so far for steering dampers that suppress vibrations such as shimmies on the front wheels of a motorcycle that is mounted on the front wheel side of a motorcycle, and among them, for example, Patent Document 1 discloses that The disclosed steering damper has a damping portion that is arranged in a so-called external manner on an outer cylinder that is connected to the vehicle body, for example, so that the generated damping force can be adjusted by an external operation. It is supposed to be done.

  That is, in the steering damper disclosed in Patent Document 1, the rod body is inserted into the inner cylinder disposed in the shaft core portion of the outer cylinder, and the piston body is held by the rod body. Two oil chambers, which are one and the other, are defined therein, and an attenuation portion is provided in a main passage that allows communication between one oil chamber and the other oil chamber.

  In this steering damper, the damping portion can adjust the size of the throttle resistance when the hydraulic oil passes through the main passage by a rotating operation with respect to the adjuster from the outside. It is said that the damping force generated in the damping part when passing through can be adjusted in level.

Therefore, in the motorcycle mounted with the steering damper disclosed in Patent Document 1, it is possible to suppress the runout of the front wheels due to shimmy and kickback that are expressed during traveling. In that case, a comfortable ride can be experienced.
JP 2004-51025 A (see paragraphs 0003 to 0005, 0008, FIG. 2, FIG. 3 in the specification)

  However, in the proposal disclosed in the above-mentioned Patent Document 1, there is no problem in suppressing the front wheel shake due to shimmy or kickback that is expressed during traveling. It may be pointed out that there is a minor defect in motorcycle riders with

  That is, in the roughly cylindrical type steering damper including the steering damper disclosed in Patent Document 1 described above, for example, the outer cylinder is connected to the vehicle body side of the motorcycle, while the inner side of the outer cylinder is The rod body inserted into the inner cylinder is connected to the handle side of the motorcycle.

  From this, in a motorcycle, even if the steering wheel is steered left and right at the same angle, the difference in operation due to the so-called lever ratio between one steered direction and the other steered direction, that is, the inner cylinder As a result, the piston speed is slow in the operation in the direction with the small stroke amount, and the piston speed is fast in the operation in the direction with the large stroke amount.

  And this difference in piston speed will be expressed as a difference in damping characteristics due to the damping valve, and for the rider of the motorcycle, which has a certain amount of attention, the steering wheel is steered to the same angle from side to side. However, there is a so-called uncomfortable feeling that may lead to a feeling of difference in feeling.

  The present invention was devised in view of such a current situation, and the object of the present invention is not to be able to suppress the shake of the front wheels due to shimmy or the like in a running motorcycle. It is to provide a steering damper that is optimal for expecting an improvement in versatility so that there is no sense of incongruity when turning left and right at the same angle, and a feeling difference is not experienced.

  In order to achieve the above-described object, the configuration of the steering damper according to the present invention basically includes an outer cylinder whose both ends are sealed with bearing members, and an inner cylinder disposed on the shaft core portion of the outer cylinder. And a rod body that is inserted into the inner cylinder while penetrating the bearing member, and a piston body that is held by the rod body and defines two oil chambers that serve as one and the other in the inner cylinder. In a steering damper in which a damping portion disposed in a main passage communicating with one oil chamber and the other oil chamber is formed in the outer cylinder, the hydraulic oil passes through while the damping portion is one and the other two. Each has a check valve that directs hydraulic oil from the oil chamber to the selected damping valve while preventing backflow, and the damping valve enables adjustment of the generated damping force by external operation. Suppose.

  Therefore, in the steering damper according to the present invention, each damping portion disposed in the main passage communicating the two oil chambers has a large or small throttle resistance when the hydraulic oil passes through the main passage by an external operation. In a motorcycle, when the steering wheel is steered at the same angle to the left and right, the hydraulic oil is passed by the so-called lever ratio between one steered direction and the other steered direction. Even if there is a difference in the squeezing resistance, the damping part corresponding to each direction can cope with the difference in the squeezing resistance when the hydraulic oil passes, so that a so-called uncomfortable feeling is not caused and the feeling difference is not experienced. It will be.

  Hereinafter, the present invention will be described based on the illustrated embodiment. As shown in FIG. 1, a steering damper according to the present invention has a rod body 2 at an axial center portion of an outer cylinder 1 constituting a so-called cylinder body. Further, the rod body 2 is formed into a double rod shape that protrudes outward from both ends of the outer tube 1.

  By the way, this steering damper is formed into a double rod type, so that in the outer cylinder 1, that is, in the illustrated embodiment, as shown in FIG. When the cross-sectional areas of the two oil chambers R1 and R2 defined by the piston body 4 are the same, and the rod body 2 protrudes and retracts with respect to the inner cylinder 3 with the same stroke, each oil chamber is passed through a main passage described later. The flow rate of the hydraulic oil that reciprocates between R1 and R2 is the same.

  As shown in FIG. 1, when the steering damper is mounted on the front wheel side of the motorcycle, the outer cylinder 1 is pivotally attached to the vehicle body side of the motorcycle (not shown), and the rod body 2 is automatically mounted. It is supposed to be pivotally attached to the handle side of a motorcycle.

  Incidentally, in the illustrated case, it is assumed that the bracket 1a provided on the outer periphery of the central portion of the outer cylinder 1 is pivotally attached to a pivotal portion T1 adjacent to the tip of the fuel tank T forming the vehicle body side in the motorcycle. The bracket 2a provided at the end of the two is connected to a so-called left and right end of the fork bracket B that forms the handle side of the motorcycle.

  In FIG. 1, symbol F indicates a front fork, symbol S indicates a steering shaft, and symbol B1 indicates a pivot fixedly connected to one end of the fork bracket B. Indicates wearing bracket.

  As described above, the steering damper according to the present invention mounted on the front wheel side of the motorcycle has two damping portions V1 and V2 formed in the outer cylinder 1, as shown schematically in FIG. The outer periphery of the cylinder 1 is provided in a so-called external manner.

  On the other hand, as shown in FIG. 2, this steering damper has two main oil chambers R1 and R2 defined by the piston body 4 in the inner cylinder 3, which are not shown in detail and not shown. It is assumed that the passages communicate with each other, and the attenuation portions V1 and V2 provided on the outer periphery of the outer cylinder 1 are arranged in the main passage.

  That is, in this steering damper, a so-called cylinder body is composed of an outer cylinder 1 and an inner cylinder 3, and a rod body 2 inserted into the inner cylinder 3 has a piston body 4 to define two oil chambers R1 and R2. The outer cylinder 1 has the two attenuation portions V1 and V2.

  The outer cylinder 1 has bearing members 11 and 12 inside both ends, and the rod body 2 penetrates the shaft core portions of the bearing members 11 and 12. The seal member 13 that comes into sliding contact is arranged in series with the bearing members 11 and 12.

  Therefore, in this steering damper, the slidability of the rod body 2 with respect to the outer cylinder 1 is ensured by the bearing members 11 and 12, and the sealing performance at the end of the outer cylinder 1 is ensured by the seal member 13. become.

  By the way, in the illustrated steering damper, the so-called cylinder body has the inner cylinder 3 inside the outer cylinder 1, and the cross section is annular between the inner periphery of the outer cylinder 1 and the outer periphery of the inner cylinder 3. It is assumed that a passage R composed of a gap is formed, and this passage R communicates with the other oil chamber R2 in the inner cylinder 3 through the opening 3a opened in the inner cylinder 3 and also communicates with the main passage. Yes.

  On the other hand, a piston body 4 provided in a substantially central portion of the rod body 2 is slidably accommodated in the inner cylinder 3, and the piston body 4 allows one oil chamber R 1 and the other to enter the inner cylinder 3. The oil chamber R2 is defined as described above.

  As shown in the drawing, one oil chamber R1 communicates with the main passage through the bearing member 11 through the open communication hole 11a, and the other oil chamber R2 communicates with the main passage through the passage R. It is said.

  Therefore, the two oil chambers R1 and R2 are connected to the communication passage 11a to the main passage when the rod body 2 protrudes and retracts with respect to the so-called cylinder body, that is, when the piston body 4 slides in the inner cylinder 3. Attenuating portion V1 to attenuating portion V2 are communicated by a route of main passage to flow path R, and so-called wide and narrow.

  The rod body 2 has an oil temperature compensation mechanism, that is, an accumulator 21 disposed on the shaft core portion of the rod body 2, and the accumulator 21 has a passage 21 a for opening the rod body 2. The passage 21a is provided with a throttle 21b so that mischief of hydraulic oil does not flow into the accumulator 21.

  In the steering damper formed as described above, the two damping portions V1 and V2 suppress the flow of hydraulic oil in the main passage that communicates the two oil chambers R1 and R2, that is, in the main passage. It functions to adjust the aperture resistance. As shown in FIG. 3, it includes a check valve 5, a damping valve 6, and an adjuster 7.

  Incidentally, in the present invention, each attenuation part V1, V2 is formed in the same structure as shown in the figure. Therefore, in realizing each attenuation part V1, V2, so-called components are provided. This is advantageous in that the number can be reduced, and so that the attenuating portions V1 and V2 are arranged on the mount portion 1b formed on the outer periphery of the outer cylinder 1 so that there is no need to worry about so-called misassembly.

  Further, in the present invention, the respective attenuation portions V1 and V2 are formed to have the same structure. Therefore, in the following description, the other attenuation portion V2 on the right side in FIG. Therefore, the description of one attenuation part V1 will be substituted.

  First, the check valve 5 directs the hydraulic oil from the oil chamber R2 (or R1) to the selected damping valve 6 while preventing so-called back flow. In the drawing, the check valve 5 is composed of an annular leaf valve. It is assumed that each of the chambers 1c opened in the mount portion 1b and communicated with the corresponding passage R (or the communication passage 11a) is arranged to be movable in the vertical direction in the drawing. In this case, it is urged in the upward direction by the urging force of the urging spring 51 disposed on the rear side which is the lower side.

  On the other hand, the damping valve 6 adjusts the throttling resistance in the flow of hydraulic oil in the main passage. In the drawing, the damping valve 6 is composed of a needle valve body and is screwed on the mount portion 1b. It is assumed that the shaft core is screwed so as to be able to advance and retreat.

  At this time, in this damping valve 6, the base end side which is the upper end side in the drawing of the needle valve body is screwed to the shaft core portion of the valve housing 61, and this base end side is rotated. In the drawing, the pointed needle portion 6a serving as the lower end portion is located in the open through hole 61b at the shaft core portion of the seat portion 61a serving as the lower end portion of the valve housing 61 in the drawing.

  In the damping valve 6, the seat portion 61 a has a flow passage that allows a flow of hydraulic oil for opening the check valve 5 around the through hole 61 b, that is, the damping valve 6. A flow path 61c communicating with the downstream side is formed, and the opening end of the flow path 61c is closed so that the check valve 5 can be opened and closed.

  In this damping valve 6, the downstream side of the damping valve 6 outside the valve housing 61 is communicated with the mount portion 1b via the opening passage 1d.

  By the way, in the damping valve 6, a distal end portion 71 a which is the lower end portion in the drawing of the output shaft 71 of the adjuster 7 rotates in the shaft core portion which is the upper end side in the drawing of the needle valve body. It is said that it is linked to the blocking state.

  In other words, the adjuster 7 shown in the figure allows the control of the damping valve 6 to be changed. In the illustrated case, the adjuster 7 is arranged on the base end side which is the upper end side in the drawing of the valve housing 61 described above. An output shaft 71 is rotatably inserted into the shaft core portion with the detent mechanism D interposed therebetween, and the distal end portion 71a of the output shaft 71 is synchronously rotated to the base end side of the needle valve body. It is said that it will be connected as possible.

  It should be noted that the rotation center line of the adjuster 7 is shown in the drawing and is assumed to be orthogonal to the axial center line of the outer cylinder 1, that is, the extending direction of the rod body 2. It is considered that the rider can easily rotate the damping parts V1 and V2.

  Therefore, in the needle valve element that is the damping valve 6 connected to the adjuster 7, the needle 7a advances and retreats when the adjuster 7 is rotated, thereby advancing and retreating the tip needle portion 6a in the through hole 61b. The area of the annular flow path formed by the tip needle portion 6 and the through hole 61b can be widened, that is, the valve opening degree of the damping valve 6 can be widened or narrowed.

  When the valve opening of the damping valve 6 is widened or narrowed, that is, when the throttle resistance when the hydraulic oil passing through the annular flow path is increased or decreased, the damping unit V1, which has the damping valve 6 is used. In V2, it is possible to select the magnitude of the squeeze resistance when the hydraulic oil passing therethrough passes.

  As a result, in the steering damper having the damping portions V1, V2, it is possible to adjust the damping force when the oil chambers R1, R2 in the inner cylinder 3 are widened and narrowed. Thus, it is possible to suppress the front wheels in the two-wheeled vehicle from being shaken finely by shimmy or from being shaken at high speed by kickback.

  In addition, in the damping parts V1 and V2 in the present invention, it is assumed that the resistance when hydraulic oil from one oil chamber passes toward the other oil chamber can be controlled independently. In a motorcycle, when the steering wheel is steered left and right at the same angle, even if there is a difference in the piston speed due to the so-called lever ratio between one steered direction and the other steered direction, In the attenuation portions V1 and V2 corresponding to the directions, it is possible to cope with the difference in resistance when the hydraulic oil passes.

  By the way, regarding the configuration of the attenuating portions V1 and V2 in the present invention, the above description can be seen from the principle shown in FIG. 4A. In each attenuating portion V1 and V2, the check valve 5 is connected to the attenuating valve 6. Are configured in parallel.

  4 (B), the damping valve 6 is connected in series with the check valve 5 in each of the damping portions V1 and V2, and is the same as that shown in FIG. 4 (A). One valve can be shared, which is advantageous in that so-called misassembly can be eliminated and an increase in the number of parts can be suppressed.

  On the other hand, FIG. 4C shows that one of the oil chambers R1 passes through the damping valve 6 in the damping parts V1, V2 that the hydraulic oil that has passed through the check valve 5 in each damping part V1, V2 faces. And the other oil chamber R2 are allowed to reciprocate the hydraulic oil.

  Incidentally, the configuration of the check valve 5 and the attenuation valve 6 in the attenuation parts V1 and V2 shown in FIG. 4 (C) reverses the arrangement location of the attenuation parts V1 and V2 in FIG. Of course, even with this configuration, there is no problem in satisfying what the present invention intends.

  As described above, in the present invention, the amount of oil when each of the damping parts V1, V2 passes the so-called hydraulic oil from one oil chamber toward the other oil chamber can be adjusted independently by varying the throttle resistance. Since it can be controlled, even if a difference in the flow rate of hydraulic fluid due to the so-called lever ratio is expressed between one steering direction and the other steering direction by a steering operation in a motorcycle, it corresponds to each direction. The damping parts V1 and V2 can cope with the difference in the flow rate of the hydraulic oil. In particular, in the motorcycle rider who has a certain amount of attention, the so-called uncomfortable feeling is not caused and the feeling difference is not experienced. Become.

  In the above description, the steering damper according to the present invention is mounted on a motorcycle. However, it is not absolutely necessary to specify the steering damper according to the intention of the present invention, and it is mounted on a bicycle as a motorcycle. Of course it is also good.

1 is a plan view showing a state in which a steering damper according to the present invention is mounted on a front wheel side of a motorcycle. FIG. 2 is a cross-sectional view schematically showing a part of the steering damper of FIG. 1. It is sectional drawing which shows the attenuation | damping part arrange | positioned at the steering damper by this invention. (A), (B), (C) is a principle figure which shows the arrangement | sequence state of the check valve in a damping part, and a damping valve, respectively.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Outer cylinder 2 Rod body 3 Inner cylinder 4 Piston body 5 Check valve 6 Damping valve 7 Adjuster 11, 12 Bearing member 11a Communication path 13 Seal F Fork bracket R Path R1, R2 Oil chamber V1, V2 Damping part

Claims (6)

An outer cylinder that seals both ends with a bearing member, an inner cylinder that is disposed in an axial core portion of the outer cylinder, a rod body that is inserted into the inner cylinder while penetrating the bearing member, and the rod body A steering damper having a piston body which is held and defines two oil chambers in the inner cylinder, and an attenuation portion which is disposed in a main passage communicating the two oil chambers is formed in the outer cylinder Each having a damping valve that allows passage of hydraulic oil while having two damping parts, and a check valve that directs hydraulic oil from the oil chamber to a selected damping valve while preventing backflow. A steering damper characterized in that the generated damping force can be adjusted by an external operation. One of the oil chambers defined in the inner cylinder is opened to the bearing member and communicates with the upstream side of one attenuation portion in the main path via a communication path extending outside the inner cylinder, and is defined in the inner cylinder. The steering according to claim 1, wherein the other oil chamber formed is communicated with the upstream side of the other damping portion in the main passage through a passage formed by a gap defined between the outer cylinder and the inner cylinder. damper. The steering damper according to claim 1 or 2, wherein the damping valve has a needle valve body that advances and retreats by rotation of an adjuster from the outside, and the needle valve body adjusts a throttling resistance in the main passage during advance and retreat. . The axial direction at the time of attachment is set to the left and right direction in the motorcycle, the outer cylinder is connected to the vehicle body side in the motorcycle, and the rod body is connected to the handle side in the motorcycle. 3. The steering damper according to 3. The outer cylinder is pivotally attached to the front end side of the axial center line in the front-rear direction on the motorcycle body side, and the rod body is pivotally attached to one end portion in the left-right direction of the fork bracket that forms the handle side of the motorcycle. The steering damper according to claim 1, claim 2, claim 3 or claim 4. 6. The steering damper according to claim 1, 2, 3, 4, or 5, wherein a rotation center line of the adjuster in the damping portion is orthogonal to the axial line of the outer cylinder.

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