JP5798944B2 - Motorcycle - Google Patents

Description

  The present invention relates to an improvement of a motorcycle.

  Generally, a suspension device called a front fork is interposed between a vehicle body and a front wheel in a motorcycle. This front fork is equipped with a suspension spring and a shock absorber in parallel. The suspension spring absorbs shocks when the vehicle travels, and the expansion and contraction associated with this shock absorption is suppressed by the shock absorber to improve the ride comfort of the vehicle. I have to.

  Moreover, some front forks have an air chamber in which gas is compressed while being compressed, and use the reaction force to absorb an impact during vehicle travel (Patent Document 1).

JP 2011-174502 A

  However, in a front fork having an air chamber that functions as an air spring as described above, heat is generated by the use of the front fork, and the internal pressure of the air chamber changes due to gas expansion and contraction due to changes in temperature and atmospheric pressure (elevation). The reaction force characteristics of the front fork will change.

  In order to keep the reaction force characteristic of the front fork within a certain range, when the reaction force of the front fork becomes larger than a predetermined value, the gas in the air chamber is discharged while the gas supply source that stores the gas. It is preferable to supply gas from the container to the inside of the front fork when the container to be attached is attached to the vehicle body frame and the reaction force of the front fork becomes smaller than a predetermined value.

  However, when a container serving as a gas supply source is attached to the vehicle body frame, it is difficult to secure a container attachment space in a motorcycle, and there is a problem that the weight of the container is increased.

  Accordingly, an object of the present invention is to provide a motorcycle that does not require a container as a gas supply source to be attached to a vehicle body frame, does not have to worry about mounting space, and can suppress an increase in weight. is there.

Means for solving the problem includes a vehicle body frame having a head pipe at the head, a steering shaft pivotally supported by the head pipe, and a front fork fixed to the steering shaft and suspending a front wheel. In the motorcycle, an air chamber that can be expanded and contracted as the front fork expands and contracts is formed, and the gas contained in the air chamber generates a reaction force according to the expansion and contraction amount of the front fork. a vessel chamber for accommodating a formed in the frame gas, a passage communicating the this vessel chamber and the air chamber, and a gas supply means provided in the middle of the passage, the gas supply means, the gas When the internal pressure of the chamber rises above the threshold value, gas is discharged from the air chamber to the volume chamber, and when the internal pressure of the chamber falls below the threshold value, Is that supplies gas to the air chamber.

  According to the present invention, the gas is accommodated in the chamber formed in the vehicle body frame, and the vehicle body frame itself is used as a container serving as a gas supply source. Therefore, it is possible to suppress an increase in weight.

1 is a side view showing a main part of a motorcycle according to an embodiment of the present invention. It is explanatory drawing which shows one embodiment of this invention in principle. (A) is a longitudinal sectional view showing in principle a front fork of a motorcycle according to an embodiment of the present invention. (B) is a side view showing a partially cutaway body frame of a motorcycle according to an embodiment of the present invention.

  A motorcycle according to an embodiment of the present invention will be described below with reference to the drawings. The same reference numerals used throughout the several drawings indicate the same parts.

  As shown in FIG. 1, the motorcycle according to the present embodiment includes a body frame 1 having a head pipe 10 at the head, a steering shaft 2 pivotally supported by the head pipe 10, and a fixed to the steering shaft 2. And a front fork 4 for suspending the front wheel 3.

  As shown in FIG. 2, an air chamber A that can be expanded and contracted as the front fork 4 expands and contracts is formed inside the front fork 4, and the gas accommodated in the air chamber A is A reaction force corresponding to the amount of expansion / contraction of the front fork 4 is generated.

  Further, the motorcycle includes a chamber B formed in the vehicle body frame 1 for containing gas, a passage 5 communicating the chamber B and the air chamber A, and the chamber B to the air chamber. And a regulator (gas supply means) 50 capable of supplying gas to A.

  Hereinafter, the front fork 4 according to the present embodiment will be described in detail. The front fork 4 includes a suspension device main body F including an outer tube 40 and an inner tube 41 inserted into the outer tube 40 so as to be able to appear and retract. A shock absorber D is accommodated in the apparatus main body F.

  In addition, a reservoir R is formed outside the shock absorber D inside the suspension apparatus main body F, and the reservoir R contains a working fluid to form a reservoir liquid chamber R1. A gas chamber A is formed by containing gas on the upper side through the surface O.

  The working fluid and gas in the reservoir R are attached to the cap member 42 and the bottom member 43 that close the upper and lower openings of the suspension apparatus main body F and the lower opening of the outer tube 40 in FIG. The suspension body F is hermetically sealed with an annular oil seal 44 and a dust seal 45 that are in sliding contact with the surface.

  In the air chamber A, gas is accommodated while being compressed, and the suspension device main body F (front fork) is always urged in the extending direction. Further, the volume of the air chamber A increases when the suspension apparatus main body F (front fork) in which the inner tube 41 exits from the outer tube 40 extends, and the suspension apparatus main body F (in which the inner tube 41 enters the outer tube 40 ( When the front fork is compressed, the internal pressure of the air chamber A changes according to the amount of expansion / contraction of the front fork, and the air chamber A generates a reaction force according to the amount of expansion / contraction of the front fork.

  Further, in the present embodiment, the front fork 4 is an air spring type front fork that does not include a suspension spring composed of a coil spring and elastically supports the vehicle body only by the reaction force of the air chamber A, and is made of metal. The weight can be reduced as compared with a front fork including a suspension spring made of a coil spring.

  Subsequently, the shock absorber D accommodated in the suspension device main body F in the front fork 4 is suspended from the cylinder 6 and the cap member 42 erected on the axial center portion of the suspension device main body F, and the rod guide 60. A rod 7 that is pivotally supported by the front fork 4 and projects in and out of the cylinder 6 as the front fork 4 expands and contracts, and a piston 8 that is held at the tip of the rod 7 and slidably contacts the inner peripheral surface of the cylinder 6.

  The cylinder 6 is partitioned into two chambers P1, P2 by the piston 8, and these chambers P1, P2 are filled with working fluid. Hereinafter, the chamber on the rod side (upper side in FIG. 2) is referred to as one chamber P1, and the chamber on the piston side (lower side in FIG. 2) is referred to as the other chamber P2. In the present embodiment, the working fluid stored in the cylinder 6 or the reservoir R is a liquid made of water, an aqueous solution, oil, or the like, and the shock absorber D is a hydraulic pressure shock absorber.

  Further, the shock absorber D is provided in the middle of the first flow path 80 that communicates the one chamber P1 and the other chamber P2, and extends the damping valve V1 that provides resistance to the working fluid that passes through the first flow path 80; A pressure side check valve C1 provided in the middle of the second flow path 81 communicating the one chamber P1 and the other chamber P2, and only allowing the working fluid to move from the other chamber P2 to the one chamber P1, and the other chamber P2. A compression-side damping valve V2 provided in the middle of the third flow path 90 communicating with the reservoir liquid chamber R1 to provide resistance to the working fluid passing through the third flow path 90, and the other chamber R2 and the reservoir liquid chamber R1. An extension side check valve C2 is provided in the middle of the communicating fourth flow path 91 and allows only the working fluid to move from the reservoir liquid chamber R1 to the other chamber P2.

  When the front fork 4 is extended so that the rod 7 is retracted from the cylinder 6, the one chamber P1 is pressurized by the piston 8, and the working fluid in the one chamber P1 passes through the first flow path 80 and moves to the other chamber P2. The shock absorber D generates a damping force due to the resistance of the expansion side damping valve V1. Further, since the working fluid corresponding to the rod volume that has retreated at this time becomes insufficient in the cylinder 6, this insufficient working fluid opens the extension side check valve C2 and passes through the fourth flow path 91, and the reservoir liquid chamber R1. To the other chamber R2.

  On the other hand, when the front fork 4 in which the rod 7 enters the cylinder 6 is compressed, the other chamber P2 is pressurized by the piston 8, and the working fluid in the other chamber P2 opens the pressure side check valve C1 and passes through the second flow path 81. To one chamber P1. Further, since the working fluid for the rod volume that has entered at this time becomes surplus in the cylinder 6, the surplus working fluid passes through the third flow path 90 and moves from the other chamber P2 to the reservoir liquid chamber R1, The shock absorber D generates a damping force due to the resistance of the compression side damping valve V2.

  That is, the shock absorber D generates a damping force with the expansion and contraction of the front fork 4 to suppress the expansion and contraction movement of the front fork 4, and compensates for the change in the cylinder volume corresponding to the rod volume that appears and disappears in the cylinder 6 by the reservoir R. doing.

  The front fork 4 is disposed between the tip 70a of the cylindrical spring receiver 70 held by the rod 7 of the shock absorber D and the protruding portion 60a of the rod guide 60 protruding from the cylinder 6 to the outer peripheral side. The balance spring S is provided.

  The balance spring S is a coil spring that urges the front fork 4 in the contracting direction within a predetermined stroke range from the time when the front fork 4 is extended to the maximum and the air chamber A when the front fork 4 is extended to the maximum. The force for urging the front fork 4 in the extending direction is offset.

  Therefore, in the present embodiment, even if the front fork 4 is always urged in the extending direction by the air chamber A functioning as a suspension spring, the contraction of the front fork 4 within the predetermined stroke range from the maximum extension is balanced. The spring S can help to quickly start the contraction of the front fork 4 in the vicinity of the maximum extension, thereby improving the riding comfort.

  Returning, the outer tube 40 in the suspension apparatus main body F is fixed to the steering shaft 2 as shown in FIG. The steering shaft 2 is pivotally supported by the head pipe 10 of the vehicle body frame 1 and is rotatable. A handle H is fixed to the upper side in FIG. On the other hand, the lower end in FIG. 1 of the inner tube 41 in the suspension device main body F is fixed to the axle of the front wheel 3. Thereby, the front fork 4 can be rotated together with the steering shaft 2 by operating the handle H, and the direction of the front wheel 3 can be changed.

  Subsequently, the vehicle body frame 1 is composed of the head pipe 10 disposed on the front side of the motorcycle and a frame main body 11 connected to the rear of the head pipe 10. In the motorcycle, an engine E is attached to the frame body 11.

  In the present embodiment, as shown in FIG. 2, the frame body 11 includes a main frame 11a extending from the head pipe 10 to the rear of the motorcycle, and a down tube 11b extending from the head pipe 10 to the lower side of the motorcycle. A pivot frame 11c for connecting the main frame 11a and the end of the down tube 11b, and a reinforcing gusset plate 11d provided between the main frame 11a and the down tube 11b. The main frame 11a is hollow and has a chamber B, and a gas is sealed in the chamber B.

  Further, the chamber B communicates with the air chamber A through the passage 5, and a regulator (gas supply means) 50 is provided in the middle of the passage 5. When the internal pressure of the air chamber A rises and falls below a predetermined level, the regulator 50 communicates the chamber B and the air chamber A, and discharges the gas in the air chamber A to the chamber B. Or a gas is supplied from the chamber B into the air chamber A.

  In addition, the detection method of the internal pressure in the air chamber A may be detected by a mechanical method such as a spring or an electrical method such as a sensor, and a known detection method may be adopted as appropriate. The timing for detecting the internal pressure may be constant at the time of discharging and supplying the gas.

  Further, the threshold value of the internal pressure of the air chamber A in which the regulator 50 is operated can be appropriately set according to a desired reaction force range of the front fork 4.

  In addition, as a specific method for discharging gas from the chamber A to the chamber B and a method for supplying gas from the chamber B to the chamber A, well-known methods can be adopted as appropriate. The above supply may be performed by another component.

  Hereinafter, the function and effect of the motorcycle according to the present embodiment will be described. In the present embodiment, when the internal pressure of the air chamber A rises above a predetermined value and the reaction force of the front fork 4 becomes larger than a predetermined value, the regulator 50 communicates the chamber B and the air chamber A, The gas in the air chamber A is discharged into the chamber B.

  On the other hand, when the internal pressure of the air chamber A falls below a predetermined value and the reaction force of the front fork 4 becomes smaller than a predetermined value, the regulator 50 communicates the chamber B and the air chamber A, and the chamber B Gas is supplied into the air chamber A.

  Therefore, by keeping the internal pressure of the air chamber A within a certain range, the reaction force characteristic of the front fork 4 can be kept within a certain range.

  In the present invention, the gas supply source for supplying the gas to the air chamber A of the front fork 4 includes the chamber B formed in the body frame 1. That is, since the vehicle body frame 1 itself is used as a container serving as a gas supply source, it is not necessary to separately attach a container to the vehicle body frame 1, and there is no concern about the installation space, and it is possible to suppress an increase in weight. It becomes possible.

  Further, the front fork in the present embodiment is an air spring type front fork that does not include a suspension spring composed of a coil spring, and elastically supports the vehicle body only by the reaction force of the air chamber A. The reaction force of the front fork Characteristics are particularly susceptible to change.

  For this reason, when a container for supplying gas to the air chamber A is attached to the vehicle body frame 1, a large-capacity container is required, and it is more difficult to secure an attachment space, which tends to increase the weight. Therefore, in the air spring type front fork, it is particularly effective to use the body frame 1 itself as a container.

  Further, in the present embodiment, when the internal pressure of the air chamber A rises above a predetermined value, gas is discharged from the air chamber A to the chamber B, and when the internal pressure of the air chamber A drops below a predetermined value, Since the regulator 50 for supplying gas to the air chamber A is provided in the middle of the passage 5, it is possible to hold the gas discharged when the internal pressure of the air chamber A rises above a predetermined level in the container B and store the pressure. Become.

  In the present embodiment, since the chamber B is formed in the main frame 11a, a gas supply source (the chamber B) can be disposed near the front fork 4, and the air chamber A and the chamber are arranged. It is possible to shorten the passage 5 communicating with B.

  Although preferred embodiments of the present invention have been described in detail above, it should be understood that modifications, variations and changes may be made without departing from the scope of the claims.

  For example, in the motorcycle according to the above-described embodiment, the front fork 4 is an air spring type front fork that does not include a coil spring. However, if the front fork 4 has an air chamber that functions as an air spring, it is metallic. A coil spring may be provided.

  The front fork 4 in the above embodiment is an inverted front fork in which the outer tube 40 is attached to the vehicle body side and the inner tube 41 is attached to the axle side, but the inner tube 41 is attached to the vehicle body side. In addition, the outer tube 40 may be an upright front fork attached to the axle side.

  Moreover, although the front fork 4 in the above embodiment accommodates the upright hydraulic shock absorber D, it uses gas as a working fluid even if it accommodates an inverted or double rod shock absorber. Even if the pneumatic shock absorber is accommodated, the cylinder 6 may be eliminated and the piston 8 may be in direct sliding contact with the inner peripheral surface of the inner tube 41, or any form of shock absorber may be accommodated.

  In the above-described embodiment, the chamber B serving as a gas supply source is formed in the main tube 11a of the vehicle body frame 1. However, as long as it is within the vehicle body frame 1, the gas supply source is located in any part. A container chamber B may be provided, and in this case as well, there is no need to separately attach a container to the vehicle body frame 1 and there is no worry about the installation space, as in the above-described embodiment.

  In the above embodiment, a regulator 50 serving as a gas supply means is provided in the middle of the passage 5 that connects the air chamber A and the chamber B, and the regulator 50 supplies and discharges gas into the air chamber A. Although the reaction force characteristic of the fork 4 is within a certain range, the configuration and position of the gas supply means are not limited to the above as long as the reaction force characteristic of the front fork 4 can be within the certain range. .

  For example, although not shown in the drawing, the air chamber A and the chamber B are always in communication with each other through the passage 5, and a movable piston serving as a gas supply means that is driven according to the internal pressure of the chamber A on the side opposite to the chamber B When the internal pressures of the air chamber A and the chamber B are lower than a predetermined value, the movable piston is moved to the air chamber side to reduce the volume of the chamber B to reduce the air chamber A and the chamber B. While the internal pressure of the air chamber A and the internal chamber B rises above a predetermined level, the movable piston is moved to the anti-air chamber side to enlarge the volume of the internal chamber B and The internal pressure of the chamber B may be lowered.

  Further, the regulator 50 as the gas supply means in the above embodiment communicates the chamber B and the air chamber A when the internal pressure of the air chamber A rises and falls below a predetermined value. The chamber B and the air chamber A may be communicated with each other only when the internal pressure of the gas drops below a predetermined value, and gas may be supplied from the chamber B into the air chamber A. In this case, a relief valve (not shown) is provided on the cap member 42 and the like, and when the internal pressure of the air chamber A rises above a predetermined value, the gas in the air chamber A is discharged to the atmosphere side by the relief valve. Is preferred.

  The vehicle body frame 1 in the above embodiment includes the main frame 11a, the down tube 11b, the pivot frame 11c, and the gusset plate 22d. However, the configuration is not limited to this, and the configuration of the vehicle body frame 1 can be selected as appropriate. It is.

A Air chamber B Volume chamber C1 Pressure side check valve C2 Extension side check valve D Buffer E Engine F Suspension device body H Handle O Liquid level P1 One chamber P2 Other chamber R Reservoir R1 Reservoir fluid chamber S Balance spring V1 Extension side damping valve V2 Compression side damping valve 1 Body frame 2 Steering shaft 3 Front wheel 4 Front fork 5 Passage 6 Cylinder 7 Rod 8 Piston 10 Head pipe 11 Frame body 40 Outer tube 41 Inner tube 42 Cap member 43 Bottom member 44 Oil seal 45 Dust seal 50 Regulator (Gas supply) means)
60 Rod guide 70 Spring receiver 80 First channel 81 Second channel 90 Third channel 91 Fourth channel

Claims (3)

A vehicle body frame having a head pipe at the front, a steering shaft pivotally supported by the head pipe, and a front fork fixed to the steering shaft and suspending a front wheel,
In the motorcycle, an air chamber that can be expanded and contracted with the expansion and contraction of the front fork is formed inside the front fork, and the gas accommodated in the air chamber generates a reaction force according to the expansion and contraction amount of the front fork.
A chamber formed in the vehicle body frame for containing gas, a passage communicating the chamber and the air chamber, and gas supply means provided in the middle of the passage ;
The gas supply means discharges gas from the air chamber to the chamber when the internal pressure of the air chamber rises above a threshold value, and from the volume chamber to the air chamber when the internal pressure of the air chamber falls below a threshold value. A motorcycle characterized by supplying gas to the vehicle. The gas supply means, a motorcycle according to claim 1, characterized in that the regulator.   The motorcycle according to claim 1 or 2, wherein the vehicle body frame includes a main frame extending rearward from the head pipe, and the chamber is formed in the main frame.

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