JP4275301B2 - Oil lock structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an oil lock structure, and more particularly, to an improvement in an oil lock structure that prevents the occurrence of an impact due to a bottom when a front fork is fully compressed.
[0002]
[Prior art and its problems]
The oil lock structure in the front fork is provided in order to prevent the occurrence of an impact due to the bottom when the front fork is in the most compression operation.
[0003]
Among them, although not shown in detail, the oil lock structure shown in FIG. 3 is a front fork with a built-in damper, and has a substantially bottomed structure that is connected to the upper end of a cylinder body C that constitutes an upright damper. An oil lock piece 2 formed in a substantially cone shape, which is held in a fixed state in a rod body R that also constitutes a damper, is fitted in an oil lock case 1 formed in a cylindrical shape (see FIG. 4). The phenomenon is expressed.
[0004]
On the other hand, after the oil lock phenomenon prevents the front fork from bottoming at the time of the most compression operation, the front fork is extended by the urging force of a suspension spring (not shown). For example, as shown in FIG. 4, the oil lock case 1 is provided with a suction check valve 3 in order to realize a quick reversal from to the extension operation.
[0005]
However, motorcycle riders such as bicycles and motorcycles equipped with the front fork equipped with the oil lock structure mentioned above point out that there is a feeling of thrust from the front fork immediately after landing after jumping. There is.
[0006]
In other words, after the oil lock phenomenon has occurred in the front fork, the front fork immediately reverses to the extension operation due to the urging force of the suspension spring. At this time, the rider's body thrusts at what is called the landing inertia. Therefore, if the check valve 3 for suction is arranged and set so as to be able to extend quickly after oil lock, the rider can be pushed up by the front fork immediately after landing. Become a bodily sensation.
[0007]
And, if you have to be prepared for the next posture to be taken instantaneously, such as in a motocross competition, the timing will be upset. Is said to have an adverse effect on steering operation.
[0008]
The present invention was devised in view of the above-described circumstances, and its object is to eliminate a feeling of pushing up from the front fork immediately after landing after jumping, and a motorcycle such as a bicycle or a motorcycle. It is to provide an oil lock structure that is optimal for expecting an improvement in versatility of the front fork so that a favorable timing can be obtained.
[0009]
[Means for Solving the Problems]
In order to achieve the above-described object, the oil lock structure according to the present invention basically exhibits an oil lock phenomenon when the oil lock piece is fitted into the oil lock case, and the oil lock case In an oil lock structure having a check valve for suction that functions to increase the withdrawal speed of the oil lock piece from inside the oil lock case, the withdrawal speed of the oil lock piece fitted in the oil lock case It is assumed that the suction check valve described above is set so as to exhibit a suction function when the oil lock piece is retracted more than a predetermined stroke in the oil lock case of the oil lock piece. .
[0010]
In the above-described configuration, more specifically, the oil lock case is, for example, disposed inside the lower end of the axle side tube constituting the front fork. At this time, the oil lock piece is inverted. It is assumed that the damping valve is held by the head portion of the cylinder body constituting the set damper, and has a leaf valve that uses the rod body constituting the damper as a center rod.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
In the following, the present invention will be described based on the illustrated embodiment. The oil lock structure according to the present invention is embodied in a front fork set upside down as shown in FIG.
[0012]
At this time, the front fork is configured such that the axle-side tube 12 at the lower end side is inserted into the upper end body-side tube 11 so as to be able to protrude and retract under the arrangement of the suspension spring 13. The mold has a damper (not shown) set.
[0013]
As described above, when the damper is built in the front fork, it is advantageous in that, for example, by setting the damper as a cartridge, a damper having a preferable damping characteristic can be freely selected.
[0014]
Incidentally, the damper is configured such that the cylinder body C is positioned on the shaft core portion of the vehicle body side tube 11, and the rod body R that is projected and retracted with respect to the cylinder body C is positioned on the shaft core portion of the axle side tube.
[0015]
The oil lock structure includes an oil lock case 1 and an oil lock piece 2. When the oil lock piece 2 is inserted into the oil lock case 1 as in the conventional case shown in FIG. It is said that the oil lock phenomenon is expressed.
[0016]
However, as shown in the figure, the oil lock case 1 is arranged inside the lower end portion of the axle-side tube 12, and the oil lock piece 2 is a head portion (notation of the cylinder body C constituting the damper). (Not shown).
[0017]
In other words, the oil lock case 1 is formed in a substantially cylindrical shape as shown in the figure, and a bottom member 14 that seals the lower end of the axle side tube 12 while being housed inside the lower end side of the axle side tube 12. The bottom member 14 is fixed to a predetermined position by being screwed between the bottom member 14 and the axle-side tube 12 by being screwed to the axle-side tube 12.
[0018]
At this time, a fixing bolt 15 is connected to the shaft core portion of the bottom member 14, and the rod portion described above is positioned while the shaft portion 15 a of the fixing bolt 15 is positioned on the shaft core portion of the lower end portion of the oil lock case 1. The rod body R is connected to the axle side tube 12 by screwing into the lower end side of the connecting member 16 to which the lower end of the body R is screwed.
[0019]
On the other hand, the oil lock piece 2 has an appearance as shown in the figure, for example, is formed in a cylindrical shape having a length smaller than the radius, and the outer peripheral surface 2 a is used as the inner peripheral surface of the oil lock case 1. The sliding contact surface with respect to 1a is set.
[0020]
By the way, in the oil lock structure according to the present invention, the oil lock case 1 has the suction check valve 3 and the damping valve 4.
[0021]
As described above, the suction check valve 3 is provided so that the oil lock piece 2 can be quickly removed from the oil lock case 1, and in that sense, in the case of the conventional oil lock structure, Although similar, the present invention is characterized by the arrangement position in the oil lock case 1.
[0022]
In other words, in the present invention, the suction check valve 3 is the so-called oil lock piece 2 when the oil lock piece 2 is inserted into the oil lock case 1 as shown in a virtual diagram in FIG. It is supposed to be set to be on the back side.
[0023]
Therefore, at this time, the suction check valve 3 does not exhibit the suction function, and therefore, the oil lock piece 2 does not contribute to the quick withdrawal from the oil lock case 1.
[0024]
On the other hand, in the present invention, when the check valve 3 for suction is retreated more than a certain stroke so that the oil lock piece 2 comes out of the oil lock case 1 as shown by a solid line in FIG. The oil lock piece 2 is set to be on the pressure receiving surface side.
[0025]
Therefore, at this time, the suction check valve 3 exhibits a suction function, and therefore contributes to the oil lock piece 2 coming out of the oil lock case 1 quickly.
[0026]
Incidentally, as long as the suction check valve 3 exhibits the suction function described above, a known configuration such as a known configuration can be adopted, and the suction check valve 3 can be used as the oil lock case 1. Since it is provided so as to penetrate the wall thickness on the upper end side of the oil lock case 1, the oil lock case 1 communicates with the upper side of the oil lock case 1 through a longitudinal groove 1 b formed on the outer periphery on the upper end side.
[0027]
Next, the damping valve 4 is assumed to have a leaf valve 41 having the rod body R constituting the damper as a center rod, as shown in the figure, and when the oil lock piece 2 comes out of the oil lock case 1. In addition, it functions to reduce the exit speed.
[0028]
Therefore, in the oil lock structure according to the present invention, as shown by the phantom diagram in FIG. 2, the oil lock piece 2 is inserted into the oil lock case 1 and exerts the oil lock effect. When the oil lock piece 2 is about to immediately come out of the oil lock case 1 due to the urging force of the spring 13, the damping valve 4 has a withdrawal speed that is the speed at which the oil lock piece 2 is pulled out of the oil lock case 1. Will function to lower.
[0029]
As a result, even if the front fork reverses to the extension operation immediately after the oil lock, the speed is reduced by the damping valve 4, and therefore, at this time, the rider's body is caused by the inertia at the time of landing. Even if it is so-called thrusting, the rider will not have the sensation of being pushed up by the front fork immediately after landing.
[0030]
And since there is no sense of being pushed up, for example, when it is necessary to prepare for the next posture to be taken instantaneously, such as in a motocross competition, the timing etc. will not go wrong, and the handle operation You don't have to worry about the negative effects.
[0031]
Not only that, the damping valve 4 includes the leaf valve 41, that is, a damping characteristic having a valve characteristic is generated. For example, in the same oil lock structure as in the prior art, the square characteristic is attenuated in a similar situation. Compared to the case where force is generated, it is advantageous in that the rider can improve the so-called riding comfort.
[0032]
Incidentally, in this damping valve 4, the leaf valve 41 is located above the valve seat member 42 disposed inside the oil lock case 1 as if the inside of the oil lock case 1 was divided in the vertical direction. It is seated in a manner in which the inner peripheral end is fixed to the end face and the outer peripheral end is free.
[0033]
The leaf valve 41 is opened in the valve seat member 42 so as to open and close the downstream end which is the upper end in the drawing of the port 42a which allows communication between the upper and lower ends thereof. The oil below the valve seat member 42 is prevented from flowing out below the valve seat member 42, and conversely, the oil below the valve seat member 42 is allowed to flow above the leaf valve 41.
[0034]
That is, the leaf valve 41 functions as an extension-side damping valve. Therefore, the oil lock case 1 includes a vertical groove 1c that allows inflow of oil from the outside to the inside, and the vertical groove. 1 d and a communication hole 1 d communicating with the inside of the oil lock case 1 are formed.
[0035]
The valve seat member 42 is sandwiched with the leaf valve 41 and the like between the engaging portion R1 formed of a flange formed on the rod body R and the connecting member 16 described above.
[0036]
Incidentally, as described above, the leaf valve 41, which is the expansion side damping valve, is adjacent to the one end surface which is the upper end surface of the valve seat member 42. It can be said that a leaf valve, which is a compression-side damping valve, may be separately provided adjacent to the other end surface which is the lower end surface of each of the two.
[0037]
If this pressure-side damping valve is disposed in a state of facing the leaf valve 41, it is necessary to set the opening port 42a on the valve seat member 42 for the expansion side and the pressure side, but the oil lock Since the pressure side damping force of the valve characteristic can be generated when the function is exerted, the pressure side damping force of the square characteristic generated in the same scene in the oil lock case 1 and the oil lock piece 2 In comparison, the rider can improve the ride comfort.
[0038]
The above is an example in which the oil lock case 1 is arranged inside the lower end side of the axle-side tube 12 constituting the front fork. From the point of view of the present invention, As in the case of the above-described conventional example, it is of course possible to be connected to the upper end of the cylinder body C that constitutes a built-in damper that is set upright. Of course.
[0039]
【The invention's effect】
As described above, in the present invention, after the oil lock piece is fitted into the oil lock case and exerts the oil lock effect, the oil lock piece is attenuated when it is about to come out from the oil lock case immediately. Since the valve functions to reduce the exit speed of the oil lock piece from the oil lock case, even if the front fork reverses to the extension operation immediately after the oil lock, the speed is reduced by the damping valve. Therefore, at this time, even if the rider's body is plunged by the inertia at the time of landing, the rider feels like being pushed up by the front fork immediately after landing. It will disappear.
[0040]
Since the damping valve has a leaf valve, it is possible to generate a damping force with a valve characteristic. For example, in a similar oil lock structure from the past, a square characteristic damping force is generated in a similar situation. This is advantageous in that the rider can improve the so-called riding comfort.
[0041]
Furthermore, when a leaf valve different from the above functioning as a compression side damping valve is provided on the opposite side of the leaf valve functioning as an extension side damping valve, an oil lock piece is fitted in the oil lock case. When the oil lock function is performed, it is possible to generate a compression side damping force of the valve characteristics. As described above, in the same oil lock structure as before, the square characteristics are attenuated in the same situation. Compared to the case where force is generated, the rider will have a better ride.
[0042]
As a result, according to the present invention, since there is no feeling of pushing up from the front fork immediately after landing after jumping, for example, when it is necessary to prepare for the posture to be taken next in a motocross competition etc. The timing is not upset, and there is no need to worry about the adverse effects on the steering wheel operation. The rider of a motorcycle such as a bicycle or a motorcycle can obtain a favorable timing, and the versatility of the front fork. It is most suitable to expect improvement.
[Brief description of the drawings]
FIG. 1 is a partial front view showing a partially broken front fork embodying an oil lock structure according to the present invention.
2 is an enlarged partial sectional view showing an operating state of the oil lock structure of FIG. 1. FIG.
FIG. 3 is a partial front view showing in principle a partial cross section of an oil lock structure as a conventional example.
4 is a view showing an operating state of the oil lock structure of FIG. 3 by a method similar to FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Oil lock case 1a Inner peripheral surface 1b, 1c Vertical groove 1d Communication hole 2 Oil lock piece 2a Outer peripheral surface 3 Suction check valve 4 Damping valve 11 Car body side tube 12 Axle side tube 13 Suspension spring 14 Bottom member 15 Fixing bolt 15a Shaft Part 16 connecting member 41 leaf valve 42 valve seat member 42a port C cylinder body R constituting the damper rod body R1 constituting the damper engaging part

Claims (1)

There is a check valve for suction that causes the oil lock phenomenon to occur when the oil lock piece is inserted into the oil lock case, and the oil lock case functions to speed up the oil lock piece withdrawing from the oil lock case. In this oil lock structure, the oil lock case has a damping valve that functions to reduce the retraction speed of the oil lock piece fitted into the oil lock case, and the suction check valve is an oil An oil lock structure that is set so as to exhibit a suction function when the lock piece is moved backward within a certain stroke in the oil lock case.

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