JP2007331696A - Steering shock absorber for saddle type vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve driving stability at an early stage, when a vehicle is accelerated from a low-speed traveling state till a high-speed traveling state. <P>SOLUTION: A steering shock absorber for a saddle type vehicle has a steering damper 21 generating a damping force in conjunction with steering motion A of a steering system 7. The damping force is set to be small when an accelerator manipulated variables for traveling drive of the vehicle 1 is less than a predetermined value D, and the damping force is set to be the predetermined value D or more. The damping force is set to be large when a change rate in increase in accelerator manipulated variables is a predetermined value E or more. The damping force is set to be small when a vehicle speed is lower than a predetermined value F, and the damping force is set to be large when it is a predetermined value F or more. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention regulates the steering operation by generating a damping force in conjunction with the steering operation of the steering system, and controls the damping force according to the state of the accelerator operation for traveling driving. The present invention relates to a steering shock absorber for a straddle-type vehicle whose size is changed.

  Conventionally, there is a steering shock absorber for the saddle-ride type vehicle disclosed in Patent Document 1 below. According to this publication, the steering shock absorber of the saddle riding type vehicle includes a steering damper that generates a damping force in conjunction with a steering system steering operation such as a front wheel, and when the vehicle speed is less than a predetermined value, The damping force is reduced, and the damping force is increased when the damping force is equal to or greater than the predetermined value.

  Here, for example, when the vehicle is operated, the vehicle speed is low, and the vehicle speed is less than the predetermined value. For this reason, according to the said structure, damping force is made small. Therefore, the steering operation in the steering system is not greatly restricted by the damping force when the vehicle is handled, and this can be done lightly and easily.

  On the other hand, when the vehicle is traveling, the front wheels in the steering system are given an impact force from the traveling surface and perform a steering operation such that the front wheels and the handle are repeatedly swung left and right. And this steering operation becomes violent as the vehicle speed becomes high, and causes a decrease in the maneuverability.

However, when the vehicle speed increases and the vehicle speed reaches the predetermined value or more as described above, the damping force is increased. For this reason, the steering operation is regulated so as to be slowed by the damping force, thereby maintaining good steering performance.
JP 2005-219617 A

  By the way, when trying to accelerate from the state where the vehicle is traveling at a low speed to the high speed traveling, this is usually performed in a substantially straight traveling state. For this reason, it is sufficient to make the steering operation at this time almost stationary. Therefore, at the time of acceleration, it is preferable that the damping force is increased to restrict the steering operation at an earlier stage to improve the maneuverability.

  However, at the beginning of the acceleration, if the vehicle speed is less than the predetermined value, and the damping force remains small, it is not expected at the beginning of the acceleration to improve the maneuverability by restricting the steering operation. The inconvenience arises.

  The present invention has been made paying attention to the above-described circumstances, and the object of the present invention is at an earlier stage when the vehicle is to be accelerated from a low-speed traveling state to a high-speed traveling state. It is to be able to improve the maneuverability.

The invention of claim 1 is a steering shock absorber for a straddle-type vehicle including a steering damper 21 that generates a damping force in conjunction with the steering operation A of the steering system 7.
When the accelerator operation amount for driving the vehicle 1 is less than the predetermined value D, the damping force is reduced, and when the accelerator operation amount is greater than the predetermined value D, the damping force is increased.

  According to a second aspect of the invention, in addition to the first aspect of the invention, the damping force is increased when the rate of change when the accelerator operation amount increases is equal to or greater than a predetermined value E.

  According to a third aspect of the invention, in addition to the first or second aspect of the invention, when the vehicle speed is less than the predetermined value F, the damping force is decreased, and when the vehicle speed is equal to or higher than the predetermined value F, the damping force is increased. It is a thing.

  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.

The invention of claim 1 provides a steering shock absorber for a saddle-ride type vehicle including a steering damper that generates a damping force in conjunction with a steering operation of a steering system.
When the accelerator operation amount for driving the vehicle is less than a predetermined value, the damping force is reduced, and when the accelerator operation amount is greater than the predetermined value, the damping force is increased.

  Here, as described above, when the accelerator operation amount is less than the predetermined value, the vehicle speed is considered to be low or to be low in the near future according to the accelerator operation amount. Therefore, this is prefetched to reduce the damping force as described above.

  For this reason, it is prevented at an earlier stage that the steering operation of the vehicle that is performed relatively frequently during low-speed traveling and the steering operation that is performed in the low-speed state are largely restricted by the damping force. Therefore, light and smooth steering and handling at a low speed of the vehicle can be performed at an earlier stage, which is convenient.

  On the other hand, when the accelerator operation amount is equal to or greater than a predetermined value, the vehicle speed of the vehicle is high or is considered to increase in the near future according to the accelerator operation amount. Therefore, this is pre-read and the damping force is increased as described above.

  For this reason, even if a steering operation is attempted such that the steering system swings left and right due to the impact force from the running surface during high-speed traveling, this is regulated at an earlier stage by the large damping force described above. Therefore, the steering operation is regulated to become slow at an earlier stage, and thus the vehicle steering performance is well maintained.

  According to a second aspect of the present invention, when the rate of change when the accelerator operation amount is increased is equal to or greater than a predetermined value, the damping force is increased.

  Here, as described above, when the rate of change when the accelerator operation amount is increased is equal to or greater than a predetermined value, the vehicle speed of the vehicle is suddenly increased, and it is considered that a high-speed running state is reached in the very near future.

  Therefore, this was pre-read and the damping force of the steering damper was increased as described above. For this reason, the regulation of the steering operation of the steering system by this damping force is immediately increased. As a result, the maneuverability can be improved by the above-described large damping force at an earlier stage when the rapid acceleration is attempted.

  According to a third aspect of the present invention, when the vehicle speed is less than a predetermined value, the damping force is reduced, and when the vehicle speed is equal to or higher than the predetermined value, the damping force is increased.

  That is, since the damping force is directly adjusted by the vehicle speed, the effect produced by the first aspect can be achieved more reliably.

  The steering shock absorber for a saddle-ride type vehicle according to the present invention can improve maneuverability at an earlier stage when the vehicle is accelerated from a low-speed traveling state to a high-speed traveling state. The best mode for carrying out the present invention in order to achieve the object is as follows.

  That is, the steering shock absorber of the saddle riding type vehicle includes a steering damper that generates a damping force in conjunction with the steering operation of the steering system. When the accelerator operation amount for driving the vehicle is less than a predetermined value, the damping force is reduced, and when the accelerator operation amount is greater than the predetermined value, the damping force is increased.

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

  In FIG. 1-3, the code | symbol 1 is a straddle-type vehicle illustrated 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 5 supported on a head pipe 3 constituting the front upper end of the body frame 2 so as to be steerable (rotated) A about its axis 4, A front wheel (not shown) supported by the lower end portion of the front fork 5 and a bar-shaped handle 6 supported by the upper end portion of the front fork 5 are provided. The front fork 5, the front wheels, and the handle 6 constitute a steering system 7 of the vehicle 1.

  The front fork 5 is inserted into the head pipe 3 and supported by a steering shaft 10 supported around the shaft center 4 so that the steering operation A can be performed, and upper and lower ends of the steering shaft 10. Upper and lower brackets 11 and 12 and a pair of left and right fork tubes 13 whose upper ends are supported by the upper and lower brackets 11 and 12 and whose lower ends support the front wheels.

  The handle 6 is supported on the upper bracket 11. The handle 6 includes a pair of left and right handle bodies 15 projecting rearward and downward from the left and right ends of the upper bracket 11, and a pair of left and right grips 16 supported by the projecting ends of the handle bodies 15. And. Of these two grips 16, the right grip 16 is supported so as to be able to go back and forward B and C to the protruding end of the handle body 15. A spring (not shown) that urges the grip 16 to rotate backward C is provided.

  A throttle valve 18 of an engine 17 that is supported by the body frame 2 and serves as a driving source for the vehicle 1 is interlocked and connected to the right grip 16 via a wire 19. When the grip 16 is rotated forward B against the spring, the throttle valve 18 is interlocked with the forward rotation B via the wire 19 to be opened. Then, driving of the engine 17 is promoted, and the vehicle 1 is accelerated. If the grip 16 is rotated backward C by the spring, the driving of the engine 17 is suppressed and the vehicle 1 is decelerated.

  A hydraulic steering damper 21 that generates a damping force in conjunction with the steering operation A of the steering system 7 is provided. The steering damper 21 includes a cylinder tube 24 having an axial center 22 extending in the width direction of the vehicle 1 in the vicinity of the front of the head pipe 3, and a pivot tube 23 pivotally supported on the head pipe 3. A cover 25 that closes each end opening in the axial direction, a piston 26 that is slidably fitted in the cylinder tube 24 in the axial direction, and the piston 26 that is positioned on the axial center 22 of the cylinder tube 24. A piston rod 27 to be coupled, and a seal body 29 attached to the outer peripheral surface of the piston 26 and elastically closing a gap 28 between the inner peripheral surface of the cylinder tube 24 and the outer peripheral surface of the piston 26 are provided. Yes.

  The ends of the piston rod 27 in the axial direction penetrate the covers 25 so as to be slidable in the axial direction. One end of the piston rod 27 is pivotally supported by a pivotal support 30 on one side of the front fork 5. The cylinder tube 24 is partitioned into first and second oil chambers 31 and 32 by the piston 26 and filled with hydraulic oil 33, respectively.

  The cylinder tube 24 is formed with a bypass oil passage 34 having the first and second oil chambers 31 and 32 communicating with each other and having an orifice in the middle. A solenoid type control valve 35 capable of opening and closing the bypass oil passage 34 is supported by the cylinder tube 24. Specifically, the valve body 36 of the control valve 35 can open and close the bypass oil passage 34.

  A vehicle speed sensor 37 for detecting the vehicle speed (km / h) of the vehicle 1, an accelerator operation amount sensor 38 for detecting an accelerator operation amount (θ) for driving the vehicle 1, these sensors 37, 38, etc. A control device 39 that electronically controls the engine 17 by inputting a detection signal, and a drive circuit 40 that connects the control valve 35 to the control device 39 are provided.

  The vehicle speed sensor 37 detects the rotational speed of the wheel to detect the vehicle speed more directly. The vehicle speed sensor 37 may detect the vehicle speed indirectly by detecting the number of rotations of the rotating body in the engine 17 or transmission and detecting the shift state (gear position).

  The accelerator operation amount sensor 38 is based on the accelerator operation amount (θ based on the forward rotation B amount (θ) from the initial rotation position of the grip 16 and the slot opening (θ) from the fully closed state of the throttle valve 18. ) Is detected.

  1-4, when the control valve 35 is opened and the bypass oil passage 34 is opened (solid line in each figure), when the steering system 7 is steered A, The hydraulic oil 33 in the first oil chamber 31 of the steering damper 21 flows toward the second oil chamber 32 while the gap 28 is opposed to the elastic force of the seal body 29. In addition to the flow in the gap 28, the hydraulic oil 33 in the first oil chamber 31 flows through the bypass oil passage 34 toward the second oil chamber 32.

  Therefore, the first characteristic with a small damping force is obtained by each flow of the hydraulic oil 33 in the steering damper 21 (FIG. 4). According to the first characteristic, the steering operation A of the steering system 7 is not greatly restricted, and the speed of the steering operation A can be further increased.

  On the other hand, when the control valve 35 is closed and the bypass oil passage 34 is closed by the valve body 36 of the control valve 35 (the chain line in FIG. 3), the steering system 7 is steered. When the operation A is performed, the hydraulic oil 33 in the first oil chamber 31 of the steering damper 21 flows toward the second oil chamber 32 while the gap 28 opposes the elastic force of the seal body 29. On the other hand, the flow of the hydraulic oil 33 through the bypass oil passage 34 is restricted.

  Therefore, the second characteristic with a large damping force is obtained by the flow of the hydraulic oil 33 only in the gap 28 in the steering damper 21 (FIG. 4). According to the second characteristic, the steering operation A of the steering system 7 is largely restricted, and the speed of the steering operation A is reduced.

  FIG. 5 shows a flowchart of control of the steering damper 21 by the control device 39, and S in the drawing indicates each step of the program.

  In FIG. 5, first, detection signals from the sensors 37 and 38 are input to the control device 39 (S2). The accelerator operation amount (θ) based on the detection signal, the rate of change (dθ / dt) when the accelerator operation amount is calculated based on the accelerator operation amount, and the vehicle speed (km / h) are predetermined values D and E, respectively. , F (S3, S4, S5), the control valve 35 is opened (S6), and the steering damper 21 provides the first characteristic with a small damping force.

  On the other hand, when at least one of the accelerator operation amount based on the detection signal, the rate of change when the accelerator operation amount increases, and the vehicle speed is greater than or equal to a predetermined value D, E, F (S3, S4, S5) The control valve 35 is closed (S7), and the steering damper 21 provides the second characteristic with a large damping force.

  According to the above configuration, when the accelerator operation amount for driving the vehicle 1 is less than the predetermined value E, the damping force is decreased, and when the accelerator operation amount is greater than the predetermined value E, the damping force is increased. ing.

  Here, as described above, when the accelerator operation amount is less than the predetermined value D, it is considered that the vehicle speed is low according to the accelerator operation amount, or will be low in the near future. Therefore, this is prefetched to reduce the damping force as described above.

  For this reason, it is prevented at an earlier stage that the steering operation of the vehicle 1 that is performed relatively frequently during low-speed traveling and the steering operation performed in the low-speed state are largely regulated by the damping force. . Therefore, light and smooth steering and handling of the vehicle 1 at a low speed can be performed at an earlier stage, which is convenient.

  On the other hand, when the accelerator operation amount is equal to or greater than the predetermined value D, the vehicle speed of the vehicle 1 is considered to be high or high in the near future according to the accelerator operation amount. Therefore, this is pre-read and the damping force is increased as described above.

  For this reason, even if it is attempted to perform a steering operation in which the steering system 7 swings to the left and right due to an impact force from the traveling surface during high-speed traveling, this is regulated at an earlier stage by the large damping force described above. Therefore, the steering operation is regulated to be slow at an earlier stage, and thus the steering performance of the vehicle 1 is maintained well.

  Further, as described above, when the rate of change when the accelerator operation amount is increased is equal to or greater than the predetermined value F, the damping force is increased.

  Here, as described above, when the rate of change when the accelerator operation amount increases is equal to or greater than the predetermined value F, it is considered that the vehicle speed of the vehicle 1 is rapidly increased and a high-speed traveling state is reached in the very near future.

  In view of this, the steering damper 21 is set to the second characteristic to increase the damping force as described above. For this reason, the steering operation A of the steering system 7 by this damping force is performed. The regulation will be increased immediately. As a result, the maneuverability can be improved by the above-described large damping force at an earlier stage when the rapid acceleration is attempted.

  In addition, although the above is based on the example of illustration, the vehicle 1 may be 3 wheels or 4 wheels, and may be an electric travel type. Further, two or more bypass oil passages 34 and control valves 35 may be provided. The control valve 35 may be capable of arbitrarily adjusting the opening degree.

It is the II sectional view taken on the line of FIG. It is a front plane fragmentary sectional view of a vehicle. It is the elements on larger scale of FIG. It is a figure which shows the 1st, 2nd characteristic of the damping force of a steering damper. It is a figure which shows the flowchart of control by a control apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vehicle 2 Body frame 3 Head pipe 4 Axle 5 Front fork 6 Handle 7 Steering system 17 Engine 18 Throttle valve 21 Steering damper 28 Gap 33 Hydraulic oil 34 Bypass oil path 35 Control valve 36 Valve body 37 Vehicle speed sensor 38 Accelerator operation amount Sensor 39 Control device 40 Drive circuit A Steering operation B Forward rotation C Reverse rotation D Predetermined value E Predetermined value F Predetermined value

Claims (3)

In a steering shock absorber for a saddle-ride type vehicle equipped with a steering damper that generates a damping force in conjunction with the steering operation of the steering system,
A straddle type characterized in that the damping force is reduced when the amount of accelerator operation for driving the vehicle is less than a predetermined value, and is increased when the accelerator operation amount is greater than or equal to the predetermined value. Vehicle steering shock absorber.   The steering shock absorber for a straddle-type vehicle according to claim 1, wherein the damping force is increased when a rate of change when the accelerator operation amount increases is equal to or greater than a predetermined value.   The straddle-type vehicle according to claim 1 or 2, wherein when the vehicle speed is less than a predetermined value, the damping force is reduced, and when the vehicle speed is higher than the predetermined value, the damping force is increased. Steering shock absorber.

Images