JPS6019030Y2 - Front forks of motorcycles, etc. - Google Patents

Description

[Detailed description of the invention] A cylindrical body is tied to the shaft of the front wheel of a two-wheeled vehicle or three-wheeled vehicle, and a fork pipe tied to the front of the vehicle body is passed through the cylindrical body. The front fork has a damping force generating mechanism attached to a piston filled with a piston and is attached to the pipe.The front fork holds the fork pipe at both ends of the cylindrical body, so it operates smoothly and provides a stable damping force.

However, since the gap between the fork pipe and the cylindrical body is generally small, it is difficult to form a damping force generating mechanism.

The present invention eliminates the above-mentioned drawbacks by forming an oil chamber inside the fork pipe and providing a damping force generating mechanism in the oil chamber.

The drawing is a longitudinal cross-sectional view of an embodiment of the present invention, in which a cylinder 1 is connected to the shaft of a front wheel of a two-wheeled vehicle or a three-wheeled vehicle through a mounting hole 2 formed at the bottom thereof.

Oil seals 3, 3 and pipe guides 4.4 are provided at both ends of this cylindrical body 1, and by fitting a fork pipe 5 tied to the front of the vehicle body, the pipe is passed through the cylindrical body 1. It is.

Further, a piston 6 attached to a fork pipe 5 is slidably fitted into the cylinder 1, and sufficiently large oil holes 7, 8 are formed at both the upper and lower ends of the piston 6 in the pipe 5, and the inside of the pipe 5 is A partition wall 9 is provided at a position approximately corresponding to the piston 6, and an O-ring 10 is provided at an appropriate position above the partition wall 9.
A cover plate 11 is provided with a cover plate 11 having an oil chamber 12 therebetween.

Furthermore, at the lower end of the fork pipe 5, an air pouch 13 is filled with compressed air to compensate for changes in oil volume due to temperature changes.
and a tire valve 1 for filling the air sac with air.
A cover plate 15 having a diameter of 4 is provided, and an oil chamber 16 is formed between the cover plate 15 and the partition wall 9.

In addition, an oil hole 17 for generating a damping force is provided in the partition wall 9, and a disk valve 19 pressed by a spring 18 is arranged on the upper surface of the oil hole 17.
16 and the cylindrical gap between the cylinder body 1 and the fork pipe 5 are filled with oil.

In this way, the present invention forms the oil chambers 12 and 16 in the fork pipe 5, and connects each oil chamber to the upper and lower parts of the piston 6 through the oil holes 7 and 8, so that there is no space between the two oil chambers. A damping force generating mechanism consisting of an oil hole 17, a valve 19, etc. is mounted on the partition wall.

Therefore, when the fork pipe 5 descends, the oil in the lower part of the piston 6 flows into the oil chamber 16 through the hole 8, and further flows into the oil chamber 12 through the oil hole 17 by pushing open the valve 19.

Since this oil flows into the upper part of the piston 6 through the oil hole 7, a relatively small damping force is generated mainly by the oil hole 17.

Further, when the fork pipe 5 rises, the oil at the upper part of the piston 6 flows into the oil chamber 12 from the oil hole 7 and enters the orifice 2.
Since the oil flows out from the oil hole 17 to the oil chamber 16 and further moves from the oil hole 8 to the lower part of the piston 6, a large damping force is generated by the orifice 20.

As described above, the present invention forms two oil chambers inside the fork pipe that communicate with the upper and lower parts of the piston, respectively, and provides a damping force generating mechanism between them.

Therefore, by utilizing a sufficiently large space, the damping force generating mechanism can be easily designed, and a predetermined damping force characteristic can be precisely obtained.

Furthermore, the oil chamber may be used to provide an air sac or the like to compensate for changes in oil volume due to temperature changes.

[Brief explanation of the drawing]

The drawing is a longitudinal sectional view of an embodiment of the present invention. In the figure, 1 is a cylinder body, 3 is an oil seal, 4 is a pipe guide, 5 is a fork pipe, 6 is a piston, 7,
8 is an oil hole, 9 is a partition wall, 12 is an oil chamber, 13 is an air sac, 16
17 is an oil chamber, 19 is a valve, and 20 is an orifice.

Claims (1)

[Claim for Utility Model Registration] An oil seal and a pipe guide are provided at both ends of a cylindrical body that is attached to the shaft of a front wheel, and a fork pipe that is attached to the front of the vehicle body is fitted into the oil seal and pipe guide. By fitting together, the fork pipe is passed through the cylindrical body, and the piston attached to the fork pipe is slidably fitted into the cylindrical body, and is separated by a partition wall having an oil hole for generating damping force. Two oil chambers are formed inside the fork pipe, and oil holes are formed at the upper and lower parts of the piston in the fork pipe, and the upper oil hole connects one of the two oil chambers to the upper part of the piston, and Connect the other oil chamber to the bottom of the piston at the bottom oil hole. A front fork for a motorcycle, etc., in which the two oil chambers and the cylindrical gap between the cylinder body and the fork pipe are filled with oil.