JPS61241288A - Front fork with antinode dive mechanism - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to an improvement of a front 7-hole equipped with an anti-nose dive mechanism for a motorcycle.

・ (Prior art) As a conventional front 7-wheel, one is known that is equipped with an anti-nose dive mechanism that prevents the front fork from rapidly sinking due to the movement of the center of gravity during braking (for example, In this case, an anti-nose valve (hereinafter referred to as an AND valve) is installed in the flow path through which hydraulic oil flows during the pressure side operation of the 70-ton 7 oak.

This AND valve shuts off the flow of hydraulic oil during braking.
0 to prevent contractions of 7 years old overnight, and 8 to the brake system! Mechanically or electrically linked.

During normal driving, the valve planter is pushed down to the initial position by the return spring, which causes the
The ND valve is held in the fully open position, and the front seven orifices absorb vibrations from the road surface to maintain a soft ride.

On the other hand, during braking, for example, the valve plunger is pulled up by the excitation force of the thread/id, and as a result, the AND valve cuts off the flow of the pressure side hydraulic oil and prevents the front 7 oak from sinking.

At this time, when the pressure of the hydraulic oil on the pressure side overcomes the spring force of the relief spring, the AND valve opens the flow path without compressing the relief spring.In other words, when the pressure rises excessively, the AND valve opens the flow path to avoid the front 7 oak from locking. It has become.

(Problem to be solved by the invention, α) By the way, such an anti-nose dive 8! Size 7
In this case, the AND valve adjusts the damping force during braking based on the relief action that opens in response to the internal pressure of the Freon), as described above. With this, when a wheel is pushed up by an uneven road surface during braking, there is a delay in the response of the relief operation, and the impact cannot be sufficiently absorbed and alleviated in a responsive manner, resulting in poor ride comfort. There was a point.

(Means for Solving the Problems) In order to solve these problems, the present invention provides a front 7 oak equipped with an anti-nose dive mechanism that increases the compression damping force during braking, and includes an anti-nose dive mechanism in the compression side flow path. In parallel with this, an acceleration sensitive valve is provided which opens when the upthrust acceleration acting on the axle exceeds a set value.

(Function) When a wheel is pushed up by an uneven road surface during braking, the acceleration-sensitive valve operates in a responsive manner and releases hydraulic oil from the pressure side oil chamber into the oil reservoir chamber, resulting in an instant 70-ton fork reduction. contracts to absorb and soften the impact.

(Example) In Fig. 1, 2 is an outer tube connected to the wheel side, 3 is a hollow tube erected from the bottom of the outer tube, and 7 is an inner tube (not shown) connected to the vehicle body that freely slides on the outer tube 2. A piston, which is inserted into the piston and fixed to its tip, is in oil-tight sliding contact with the inner circumferential surface of the tube 2 and the outer circumferential surface of the hollow tube 3, thereby defining oil chambers above and below the piston.

A indicates an oil chamber that contracts during pressure side operation, and when this oil water A contracts, the hydraulic oil flows into the expanding oil chamber at the upper part (not shown), and the hydraulic oil corresponding to the volume entered by the inner tube is The oil flows into the oil reservoir chamber B in the hollow tube 3 through the anti-nose dive mechanism 19 (however, the specific structure is not shown).

A flow path 4 communicating between the oil chamber A and the oil reservoir chamber B is formed in the front 7 oak 1 in parallel with the flow path passing through the anti-nose dive mechanism 19, and an acceleration-sensitive valve 5 is provided in the middle of this flow path 4. (hereinafter referred to as a G-sensitive valve) is installed.

The G-sensitive valve 5 has an acceleration-sensitive spool 7 slidably inserted into the valve housing 6.
When the spool 7 slides in the same direction as the axis of the oak 1 and moves downward, it separates from the valve seat part 10 and opens, communicating the oil chamber A side boat 8 and the oil sump chamber B side port 9. do.

Then, the spool 7 is urged toward the closing side so that it rises to the return spring 12 and seats on the valve seat part 10, and returns when an inertia force exceeding a set value acts, such as when the wheel is pushed up by an uneven road surface. spring 12
The valve opens while compressing. Note that when the spool 7 is separated from the valve seat portion 10, the boats 8 and 9 communicate with each other via the small diameter portion 11 on the outer periphery of the spool 7.

The outer diameter of the spool 7 and the valve seat diameter D2 are set to be approximately the same.
The pressure on the oil reservoir chamber B side is introduced through 14, and the pressure of 70 ton 7
The spool 7 is designed not to receive thrust in any direction as the internal pressure of the oak 1 fluctuates.

Therefore, under normal conditions, the spool 7 has a holding force ΔF=-x-
It is held in the closed position by (k: spring constant of return spring 12, Xo: amount of deflection of return spring 12).

In this state, when the wheel is pushed up, its acceleration G
is the set acceleration α. The spool 7 moves in the opening direction when the distance is exceeded. In other words, while the valve housing 6 moves upward together with the outer tube 2 due to the thrust, the spool 7 tends to remain at that position due to inertia, so the spool 7 separates from the valve seat portion 10.

At this time, the spool 7 is closed by the holding force ΔF, so if its mass is m, the set acceleration at which the spool 7 starts to open is α. =ΔF/m.

The amount of displacement of the mater spool 7, that is, the amount of deflection of the return spring 12 is x=(G-α.)n+/, and the valve opening corresponding to the acceleration G is obtained.

Therefore, the upthrust acceleration at which the G-sensitive valve 5 starts to open can be arbitrarily set by the spring load of the return spring 12 and the mass of the spool 7.

As described above, according to this embodiment, the flow path 4 that communicates the oil chamber A and the oil reservoir chamber B is provided in parallel with the flow path passing through the anti-nose dive mechanism 19 in the 70-ton 7-year-old 1. Since the G-sensitive valve 5 is provided in this flow path 4, when the wheel is pushed up due to unevenness of the road surface during braking, the G-sensitive valve 5 adjusts the push-up acceleration G regardless of the internal pressure of the front oak 1. When G exceeds the set value, the pressure-side hydraulic oil is immediately relieved by opening the valve corresponding to the acceleration G (G
(cancellation action), the impact from the road surface is absorbed and alleviated with better response than before, improving ride comfort.

Incidentally, the anti/-sub-build mechanism 19 and the G-sensitive valve 5 can be designed independently according to the required characteristics.

2 to 4 respectively show other embodiments of the G-sensitive valve, and in the second embodiment shown in FIG. is formed.

In addition, in the above embodiment, if the perpendicularity or coaxiality of the valve seat portion 10 is poor, hydraulic oil leaks when the valve is closed, which causes variations in the damping force on the AND valve operating pressure side.
In this embodiment, since the spool 7A is wrapped by δ, leakage of hydraulic oil is prevented.

FIG. 3 shows an embodiment in which a G-sensitive valve 5B is added with an AND valve operation range damping force adjustment g function. In this case, rotating the dial 20 changes the set position of the cam 21, thereby adjusting the adjustment rod 22. The closed area of the orifice 23 is changed by moving in the axial direction. The damping force during braking when the AND valve is closed is determined by this orifice 2.
It is set by the initial opening degree of 3. Note that the spool 7B is operated by the thrusting load regardless of the position of the adjustment rod 22.

In the embodiment shown in FIG. 4, there is a notch 2 in the lap part of the spool 7C
4 (orifice) and turn the dial 25, the set position of the cam 26 changes, and the spool 7C is displaced in the axial direction via the adjustment rod 27. In other words, the amount of wrap and the area of the orifice are simultaneously adjusted to rf4. I'm starting to get it.

According to this, it is possible to simultaneously adjust the time during which the spool displacement amount becomes the wrap amount δ, that is, the G cancel operation time, and the compression side damping force, and it becomes easy to optimally set the anti-nose die effect and the G cancel effect.

Figure 5 shows the anti-nose dive mechanism 30 and the G-sensitive valve 5.
In this embodiment, the outer tube 2D only needs to be provided with one mounting seat, and the front 7
Since the number of man-hours required to process the oak ID is small, costs can be reduced.

In this case, communication ports 3i and 32 are formed in the valve hatch 6D to constantly communicate with the boats 8 and 9, and the boats 33 and 34 of the anti-subject mechanism 30 are connected to these ports 31 and 32. The valve body 35 is connected to the valve haunong 6D. The connection between the boats 33 and 34 is opened and closed by an AND valve (not shown).
Since the AND valve is open except during braking, during pressure side operation, hydraulic oil flows from boat 8 through boat 31 to boat 33, then flows through the AND valve to boat 34, and from boat 32 through boat 9. and flows into the oil sump room.

Note that the AND valve closes during braking, but when uplift is received, the G-sensitive valve 5D opens, allowing hydraulic oil to flow from the boat 8 to the boat 9.

(Effects of the Invention) In summary, according to the present invention, a G-sensitive valve is provided in parallel with the anti-nose dive mechanism in the flow path through which hydraulic oil flows when the front 7-au is operated on the pressure side, so that it is not pushed up from the road surface during braking. When a vehicle is hit by a vehicle, the G-sensitive valve operates to absorb and alleviate the impact in a responsive manner, thereby improving riding comfort.

Figure 2 Figure 3 Procedure Correction Office July 15, 1985 Patent Application No. 84321 23 Name of Invention Front 7 Ori with Anti-Nose Gup Mechanism 3, Person Who Makes Amendment Relationship with the Case Patent Application Address World Trade Center Building 2-4-1 Hamamatsucho, Minato-ku, Tokyo Name (092) Kayaba Kogyo Co., Ltd. 4゜Agent 5゜Date of amendment order Detailed explanation of 1 invention in the specification subject to the voluntary 66 amendment Column and drawing “Figure 1”
, "Figure 5".

7. Contents of correction (1) In the 15th line of page 2 of the specification, the phrase "the valve plunger is pulled up" is amended to read "the valve plunger is pushed down."

(2) Figures 1 and 5 of the drawings will be corrected as shown in the attached sheet.

Claims (1)

[Claims] In a front fork equipped with an anti-nose dive mechanism that increases compression-side damping force during braking, an acceleration-sensitive valve is installed in the flow path through which hydraulic oil flows during compression-side operation in parallel with the anti-nose dive mechanism, which opens when the acceleration due to thrust exceeds a set value. A front fork with an anti-nose dive mechanism featuring a molded valve.