JP3583839B2 - Front fork - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an improvement of a front fork mounted on a motorcycle.
[0002]
[Prior art and its problems]
In recent years, motorcycles are often adjusted in height so that they can respond to changes in the rider's body type and preference and also the load capacity. It is preferably performed simultaneously on both the side and the front wheel side.
[0003]
The vehicle height adjustment on the rear wheel side is performed by adjusting the stroke of a hydraulic shock absorber serving as a cushion unit mounted on the rear wheel side. However, the vehicle height adjustment on the front wheel side is conventionally performed by a hydraulic shock absorber mounted on the front wheel side. It is allegedly due to a change in the mounting position of the front fork.
[0004]
That is, the front fork is, for example, an upright type in which the lower end side of an inner tube serving as a vehicle body (handle) side member is inserted into an outer tube serving as an axle (wheel) side member so as to be able to protrude and retract. In this case, the connection position with respect to the upper end side of the inner tube of the bridge structure including the upper bracket and the under bracket is changed.
[0005]
However, when changing the connection position of the bridge structure to the inner tube, particularly when the re-connection work after disconnection is incomplete, the connection of the bridge structure to the inner tube is loosened, and the steering stability is reduced. There is a fear that it will not be possible to obtain the situation and that it will be an undesirable situation.
[0006]
Therefore, there is a proposal of a front fork as shown in FIG. 3, for example, which realizes a front-wheel-side vehicle height adjustment by adjusting a stroke of a front fork, instead of changing a connecting position with respect to an inner tube having a bridge structure.
[0007]
That is, in the front fork, a lower end side of an inner tube 2 serving as a vehicle body (handle) side member is inserted through an outer tube 1 serving as an axle (wheel) side member so as to be able to protrude and retract, and a hollow core is formed in a shaft core portion of the outer tube 1. A rod 3 is disposed, and an oil hole rod (not shown) is disposed on an outer periphery of a lower end portion of the hollow rod 3.
[0008]
The head portion 3a, which is the upper end of the hollow rod 3, is located inside the inner tube 2, and an oil lock piece 5 is arranged on the inner periphery of the lower end portion of the inner tube 2. Faces the oil hole rod.
[0009]
That is, when the inner tube 2 is largely sunk into the outer tube 1 and the front fork is fully compressed and reaches the bottom state, the inner circumference of the oil lock piece 5 is initially between the outer circumference of the oil hole rod 4. Is formed so as to exhibit a cushioning effect by forming a narrow gap allowing oil to pass therethrough, and thereafter slide in contact with the outer periphery of the oil hole rod 4 to prevent the passage of oil, thereby exhibiting an oil locking effect. .
[0010]
On the other hand, a valve 6 is provided adjacent to the upper end of the oil lock piece 5, and at the upper end of the valve 6, the inner tube 2 is greatly protruded from the outer tube 1 so that the front fork is extended. At this time, the lower end of a buffer spring 7 that prevents the valve 6 from colliding with the head 3a is brought into contact with the upper end of the buffer spring 7 and is locked to the head 3a.
[0011]
In the front fork formed as described above, by providing a so-called optional collar member S between the head portion 3a and the buffer spring 7, it is possible to adjust the stroke of the front fork. I have.
[0012]
Therefore, with the arrangement of the collar member S, the stroke position when the inner tube 2 is extended and cut with respect to the outer tube 1 is changed to be low, and accordingly, the vehicle height on the front wheel side of the motorcycle is adjusted to be low. By selecting the color members S having different lengths, adjustment with different strokes, that is, vehicle height adjustment can be performed.
[0013]
However, the above-described stroke adjustment of the front fork is realized by disposing the collar member S at the time of assembling the front fork. This is realized by the disassembly work at the factory or the like, which is a troublesome situation.
[0014]
The present invention has been made in view of such circumstances, and an object of the present invention is to make it possible to adjust a desired vehicle height by a stroke adjustment with a simple operation without disassembling work. Is to provide a fork.
[0015]
[Means for Solving the Problems]
In order to achieve the above-described object, the configuration of the present invention is configured such that a lower end side of an inner tube serving as a vehicle body-side member is inserted into an outer tube serving as an axle-side member so as to be able to protrude and retract, and is disposed on an inner periphery of a lower end portion of the inner tube. The oil lock piece is screwed in a liquid-tight structure on the inner periphery of the lower end of the outer tube in the front fork which is opposed to the oil hole rod disposed on the outer periphery of the lower end of the hollow rod standing upright on the shaft core of the outer tube. A movable bolt having a cylindrical shape, and a connecting bolt screwed to the inner periphery of the lower end of the hollow rod through a hollow shaft of the movable bolt while being locked by the movable bolt. The lower end of the hollow rod is brought into contact with the upper end of the movable bolt by screwing the connecting bolt onto the inner periphery of the lower end of the hollow rod, and the oil hole rod is formed on the outer periphery near the lower end of the hollow rod. It is sandwiched between the upper end of the movable bolt, a movable bolt, which are movable up and down within the peripheral lower end portion of the outer tube by the rotation operation from the lower end outside of the outer tube has a bore Insert tool.
[0016]
Preferably, a lock bolt for preventing removal of the movable bolt is screwed around the inner periphery of the lower end of the outer tube, and the lock bolt has a through hole for allowing a tool from outside to be inserted into the shaft core. It is assumed that a cap is detachably attached to the through hole.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described based on an illustrated embodiment. As shown in FIG. 1, a front fork according to this embodiment has an axle (wheel) side member similar to the above-described conventional front fork. A lower end side of an inner tube 2 serving as a vehicle body (handle) side member is inserted into the barrel outer tube 1 so as to be able to protrude and retract.
[0018]
A hollow rod 3 is disposed on the shaft core of the outer tube 1, and an oil hole rod 4 is disposed on the outer periphery of the lower end of the hollow rod 3.
[0019]
In addition, although not shown, the head portion, which is the upper end of the hollow rod 3, is located inside the inner tube 2 (see FIG. 3).
[0020]
On the other hand, an oil lock piece 5 is arranged on the inner periphery of the lower end of the inner tube 2, and the oil lock piece 5 faces the oil hole rod 4.
[0021]
That is, when the inner tube 2 is largely sunk into the outer tube 1 and the front fork is fully compressed and reaches the bottom state, the inner circumference of the oil lock piece 5 is initially between the outer circumference of the oil hole rod 4. Is formed so as to exhibit a cushioning effect by forming a narrow gap allowing oil to pass therethrough, and thereafter slide in contact with the outer periphery of the oil hole rod 4 to prevent the passage of oil, thereby exhibiting an oil locking effect. .
[0022]
At the upper end of the oil lock piece 5, a valve 6 is provided adjacent to the upper end of the valve 6. When the inner tube 2 protrudes greatly from the outer tube 1 to be in an extended state, The lower end of a buffer spring 7 for preventing the valve 6 from colliding with the head is abutted, and the upper end of the buffer spring 7 is locked to the head, not shown.
[0023]
Incidentally, in the present invention, the inner periphery lower end of the outer tube 1, the movable rod 8 formed on headed tubular shape are screwed to the state of the liquid-tight structure by Haizai seal 9, the The movable bolt 8 is turned from the outside of the lower end of the outer tube 1 by a turning operation of a tool inserted into a hexagonal hole 8a which is a tool insertion hole formed at the lower end of the outer tube 1 by a turning operation. It is set so that it can move up and down on the inner circumference.
[0024]
The state shown in the figure is a state in which the movable bolt 8 is in the highest position, and the length indicated by the symbol L in the figure is obtained by the above-described turning operation and in connection with the arrangement of the lock bolt 11 described later. It is set so that it can descend.
[0025]
FIG. 2 shows a state in which the movable bolt 8 is lowered at the inner periphery of the lower end portion of the outer tube 1.
[0026]
On the other hand, a connection bolt 10 locked by the movable bolt 8 is inserted through the hollow shaft core of the movable bolt 8, and the upper thread 10 a of the connection bolt 10 is attached to the hollow rod 3. It is screwed on the inner circumference of the lower end.
[0027]
Therefore, by screwing the connection bolt 10 onto the inner periphery of the lower end of the hollow rod 3, the hollow rod 3 is drawn toward the movable bolt 8, and the lower end of the hollow rod 3 is fixed to the upper end of the movable bolt 8. Will be abutted.
[0028]
At this time, it is assumed that the oil hole rod 4 is fixedly held between the locking portion 3 b formed on the outer periphery near the lower end of the hollow rod 3 and the upper end of the movable bolt 8, The rod 3 and the oil hole rod 4 are integrated.
[0029]
Therefore, according to the present invention, when the movable bolt 8 is moved up and down on the inner periphery of the lower end of the outer tube 1, the hollow rod 3 is also moved up and down at the same time. Since the inner tube 2 is moved up and down, the stroke of the inner tube 2 with respect to the outer tube 1, that is, the stroke of the front fork can be adjusted.
[0030]
When the movable bolt 8 is lowered, the oil hole rod 4 is also lowered. Therefore, the stroke for exerting the cushion effect and the oil lock effect at the time of the maximum compression is shortened. Needless to say, a necessary effective stroke can be ensured by setting the elevating length L.
[0031]
In the embodiment shown in the drawings, it is assumed that a lock bolt 11 for preventing the movable bolt 8 from coming off is screwed to an inner periphery of a lower end portion of the outer tube 1 below the movable bolt 8. Reference numeral 11 denotes that the shaft has a through hole 11a through which a tool can be inserted from the outside, and a cap 12 which is detachably and elastically deformable is attached to the through hole 11a. .
[0032]
Therefore, in this embodiment, the dismounting of the movable bolt 8 is prevented in advance by the arrangement of the lock bolt 11, and the turning operation of the movable bolt 8 by using a tool is enabled by removing the cap 12, so that the cap By mounting 12, the intrusion of mud into the lower end of the outer tube 1 can be prevented.
[0033]
Therefore, in the front fork formed as described above, when the inner tube 2 extends and retracts in the outer tube 1, a predetermined damping action is exerted. When the movable bolt 8 screwed on the inner periphery of the lower end is moved up and down, the stroke of the inner tube 2 with respect to the outer tube 1 can be adjusted.
[0034]
The lifting and lowering of the movable bolt 8 can be realized without disassembling the front fork, that is, by a rotating operation using a tool from outside the lower end of the outer tube 1.
[0035]
【The invention's effect】
INDUSTRIAL APPLICABILITY As described above, according to the present invention, in an upright type front fork, a movable body which enables a stroke adjustment of an inner tube as a vehicle body member with respect to an outer tube at a lower end inner periphery of an outer tube as an axle member is provided. Since the movable bolt has a bolt and the movable bolt can be rotated by using a tool from outside the lower end of the outer tube, it is needless to say that the front fork is not released from the bridge structure. There is an advantage that desired stroke adjustment can be easily realized without requiring disassembly of the front fork.
[0036]
In the front fork, a lock bolt for preventing the movable bolt from coming off is screwed into the inner periphery of the lower end of the outer tube, and the lock bolt has a through hole for allowing a tool from the outside to pass through the shaft core. And, when a cap is detachably attached to the through-hole, the movable bolt is prevented from dropping off by the lock bolt, and the movable bolt can be rotated by using a tool by removing the cap. The mounting of the cap has an advantage that the intrusion of mud into the lower end of the outer tube can be prevented.
[0037]
As a result, according to the present invention, it is possible to adjust the desired height of the upright front fork mounted on the motorcycle by performing a predetermined stroke adjustment with a simple operation while maintaining the mounted state. Can be easily realized.
[Brief description of the drawings]
FIG. 1 is a partial front view showing a lower half of a front fork according to an embodiment of the present invention, partially cut away.
FIG. 2 is a partial front view showing a state where a stroke is adjusted in the front fork of FIG. 1;
FIG. 3 is a partial front view showing a front fork capable of adjusting a conventional stroke, with a part cut away.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Outer tube 2 Inner tube 3 Hollow rod 3b Engagement part 4 Oil hole stick 5 Oil lock piece 8 Movable bolt 8a Hexagonal hole 9 as a tool insertion hole 9 Seal forming a liquid-tight structure 10 Connecting bolt 11 Lock bolt 11a Through hole 12 Cap

Claims (2)

The lower end of the inner tube as the vehicle body side member is inserted into the outer tube as the axle side member so as to be able to protrude and retract, and an oil lock piece disposed on the inner periphery at the lower end of the inner tube is hollow at the shaft core of the outer tube. In a front fork opposed to an oil hole rod arranged on the outer periphery of a lower end of a rod, a cylindrical movable bolt screwed into a liquid-tight structure on an inner periphery of a lower end of an outer tube, and the movable bolt is engaged with the movable bolt. state becomes a, a connecting bolt which is screwed into the lower end inner periphery of the hollow rod is inserted through the hollow axial core portion of the movable volts, threaded into the lower end inner periphery of the hollow rod of the connecting bolt The lower end of the hollow rod is brought into contact with the upper end of the movable bolt by the attachment, and the oil hole rod is sandwiched between the upper end of the movable bolt and the locking portion formed on the outer periphery near the lower end of the hollow rod. Bo DOO, which are movable up and down in the inner circumference of the lower end of the outer tube by the rotation operation from the lower end outside of the outer tube has a bore Insert tool front fork A lock bolt for preventing the movable bolt from coming off is screwed around the inner periphery at the lower end of the outer tube, and the lock bolt has a through hole that allows a tool from outside to be inserted into its shaft core, 2. The front fork according to claim 1, wherein a cap is detachably attached to the through hole.

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