JPH0798505B2 - Stroke detection device for hydraulic shock absorber control mechanism for motorcycles, etc. - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a stroke detection device for a vehicle hydraulic shock absorber with a control mechanism for vehicle height adjustment and the like. It is possible to improve the reliability and durability of the operation of a switch that detects long and short with an ON / OFF switch.

[Prior art]

It is conventionally known that a control mechanism for automatically expanding and contracting a buffer hydraulic cylinder for vehicle height adjustment and the like is provided. This one detects that the buffer hydraulic cylinder has expanded or contracted by a predetermined amount or more, and controls the switching valve based on this detection signal to adjust the hydraulic pressure of the hydraulic cylinder to expand or contract the hydraulic cylinder. A contact switch is provided on the inner wall surface of the outer cylinder of the double-cylinder shock absorber as one of the means to detect that the hydraulic cylinder has expanded or contracted more than a predetermined amount with the ON / OFF switch. There are some that can be turned on and off. This is a great merit in that the expansion / contraction detection mechanism of the buffer hydraulic cylinder and the control by the detection signal are simple and can be manufactured at low cost. However, this conventional technique has a problem in that the reliability and durability of its operation are impaired because the contact of the contact switch is inevitably worn and deteriorated.

[Problems to be Solved by the Invention]

An object of the present invention is to reduce the wear and deterioration of the contacts of the contact switch as much as possible and improve the reliability and durability of the operation of the above-mentioned conventional technology.

[Means taken to solve the problem]

Means taken for solving the above-mentioned problem is constituted by the following elements (a) and (b) on the premise of the above-mentioned conventional technique.

(A) A fixed contact is provided on a fixed structure including a cylinder of a hydraulic cylinder for cushioning and a piston rod that is attached to a vehicle frame, and a movable contact is provided on a movable structure including a cylinder attached to an axle support member. (B) The fixed contact is located below the hydraulic oil surface of the hydraulic shock absorber and is embedded in the hydraulic oil, and the movable contact and the fixed contact are brought into contact with each other in the hydraulic oil.

[Work]

The fixed contact is on the fixed structure with the piston rod attached to the vehicle frame of the buffer hydraulic cylinder, and because it is always buried in the hydraulic oil, it is protected by the hydraulic oil and its deterioration is suppressed as much as possible. Since the contact point and the movable contact point come into contact with each other in the hydraulic oil, wear of the contact point is suppressed as much as possible by the lubricating effect of the hydraulic oil. Therefore, the reliability and durability of the operation of the contact switch due to wear and deterioration of the contacts are improved. Further, since the fixed contact is provided on the fixed structure of the buffer hydraulic cylinder, it is not necessary to loosen the wiring connected thereto, and the vibration of the wiring is small,
The violent vibration does not damage the connection point of the wiring or break the wiring itself. Therefore, the durability and reliability of the wiring are improved.

〔Example〕

Next, an embodiment will be described with reference to FIGS. 1, 2, and 3.

A piston rod of a double cylinder type hydraulic shock absorber 19 with a stroke adjusting mechanism is attached to a vehicle body frame 11 of a motorcycle equipped with an engine 13, and a cylinder is attached to a rear arm 15 that supports an axle of a rear wheel 17.

The hydraulic shock absorber 19 is composed of a shock absorbing spring 21 and a hydraulic attenuator 23 including an inner cylinder (that is, a cylinder) 25, a piston 29, a piston rod 31, a throttle 25a, and the like. Is filled with hydraulic oil O. The inner cylinder 25 has a mounting bracket 27 at its end for mounting on the rear arm (that is, the axle support member). The piston rod 31 has a body frame at its end.
It has a mounting bracket 33 for mounting on 11.

The inner cylinder (cylinder) 25 and the cover cylinder 41 fixed to the mounting bracket 27 are members constituting the cylinder side of the buffer hydraulic cylinder, and constitute a movable structure that moves up and down by swinging of the rear arm. The piston rod 31 and the outer cylinder 43 fixed to the mounting bracket 33 are members constituting the piston rod side of the buffer hydraulic cylinder, and constitute a fixed structure attached to the body frame 11 that does not swing like the rear arm. To do. And the cover cylinder
41 is fitted to the outer cylinder 43 via a seal 45. The inner space of the outer cylinder 43 communicates with the inside of the inner cylinder 25 through the inner space of the cover cylinder 41 and the through hole 39 at the lower end of the inner cylinder 25.

The lower half of the inner space of the outer cylinder 43 is filled with the hydraulic oil O, and the upper half of the inner space is filled with the high-pressure gas A. Open / close and switch the electromagnetic switching valve V
The high-pressure gas A of 43 is supplied and discharged to adjust the pressure of the hydraulic oil O, thereby expanding and contracting the hydraulic shock absorber 19 to control its stroke. Opening / closing and switching control of the electromagnetic switching valve V is performed by turning on the contact switch 51 attached to the outer cylinder 43,
It is done by OFF.

The contact switch 51 has a lower end basic terminal 53, a lower terminal 57, and an upper terminal 55, and these terminals are below the oil surface of the hydraulic oil in the outer cylinder 43 and are always buried in the hydraulic oil. The mounting position of the contact switch 51 is selected so that
The base terminal 53 is always in contact with the outer surface of the conductive cover cylinder 41, and the upper terminal 55 is arranged so as to contact with the upper end of the cover cylinder 41 when the hydraulic shock absorber 19 contracts more than a predetermined amount.
57 is a cover cylinder 41 when the hydraulic shock absorber 19 extends more than a predetermined length.
It is arranged so as to come into contact with the conductive interposition plate 59 fixed to the upper end.

FIG. 2 shows the free state in which the hydraulic shock absorber 19 is most extended. However, when the hydraulic shock absorber 19 is attached to the vehicle and is under a normal load, the upper end of the cover cylinder 41 is composed of the lower terminal 57 and the upper terminal 55. The lower terminal 57 is located between them, and the lower terminal 57 is located below the intervening plate 59. In this state, the electromagnetic switching valve V is closed.

When the load increases and the hydraulic shock absorber contracts excessively, the upper terminal 55 comes into contact with the upper end of the cover cylinder 41, whereby the basic terminal
53 and the upper terminal 55 are electrically connected via the cover cylinder 41. Due to this electrical connection, the electromagnetic switching valve V is opened via the wiring 58,
By this valve opening, the outer cylinder 43 is further filled with high-pressure gas from the gas pressure source to increase the pressure of the hydraulic oil O, and the hydraulic shock absorber is extended until the upper terminal 55 is separated from the upper end of the cover cylinder 41.

On the contrary, when the load is reduced and the hydraulic shock absorber is excessively extended, the lower terminal 57 comes into contact with the intervening plate 59 at the upper end of the cover cylinder 41, whereby the base terminal 53 and the lower terminal 57 pass through the cover cylinder 41. Conduct. Due to this conduction, the electromagnetic switching valve V is opened via the wiring 58. By this opening, the high pressure gas A in the outer cylinder 43 is discharged to the atmosphere to reduce the pressure of the hydraulic oil O, and the lower terminal 57 causes the lower terminal 57 to cover the cover cylinder 41. The hydraulic shock absorber is contracted until it is separated from the intervening plate 59 at the upper end.

The oil level of the hydraulic oil in the outer cylinder 43 rises and falls as the hydraulic shock absorber 19 expands and contracts, but the terminals 53, 57, 55 are still kept buried in the hydraulic oil in the outer cylinder 43. .
Therefore, the contact surfaces of the terminals 53, 57, 55 are always protected by the hydraulic oil, and when sliding on the cover cylinder, the sliding surfaces are always lubricated by the hydraulic oil, so that the contact surfaces of the terminals and the cover cylinder are not worn. To be prevented.

Further, since the contact switch 51 is provided on the outer cylinder 43 on the fixed side, it is not necessary to loosen the wiring 58 between the contact switch and the electromagnetic switching valve V, and it is not subjected to severe vibration. The wiring does not break due to this vibration. Reference numeral 20 is a fuel tank, 22 is a seat, and 35 and 37 are spring seats.

[Effect]

The invention that solves the above-mentioned problems of the present invention is not yet known.
Therefore, the problem of the present invention is a novel problem, and the fact that the problem is solved for the first time and the problems of the above-described conventional techniques are solved is a unique effect of the present invention.

That is, the present invention provides the reliability and durability of the operation of the contact switch with respect to the above-mentioned conventional technology which automatically compensates for the excessive expansion and contraction of the hydraulic shock absorber by turning the contact switch on and off. It has been possible to improve the practicality of the above-mentioned conventional technology.

[Brief description of drawings]

FIG. 1 is a front view of a motorcycle to which an embodiment of the present invention is applied, FIG. 2 is an enlarged sectional view of a II portion of FIG. 1, and FIG. 3 is a sectional view of III-III of FIG. 19 …… Multi-cylinder hydraulic shock absorber, 21 …… Buffer spring, 23 …… Hydraulic damper, 25 …… Inner cylinder, 31 …… Piston rod, 41 …… Cover cylinder, 43 …… Outer cylinder, 51 …… Contact Switch, 53 …… Basic terminal, 55 …… Upper terminal, 57 …… Lower terminal, 58 …… Wiring, A …… High pressure gas, O …… Operating oil, V …… Electromagnetic switching valve.

Claims (1)

[Claims] 1. A hydraulic buffer for a vehicle having a control mechanism, comprising a buffer spring, a hydraulic cylinder, and a control mechanism for the hydraulic cylinder, the piston rod side of the hydraulic cylinder being attached to the vehicle frame, and the cylinder side being attached to an axle support member. In this device, a fixed contact is provided on the fixed structure equipped with the piston rod attached to the frame, and a movable contact is provided on the movable structure equipped with the cylinder attached to the axle support member. A stroke detecting device for a hydraulic shock absorber control mechanism for a motorcycle or the like, which is located below and is immersed in the hydraulic oil so that the movable contact and the fixed contact are brought into contact with each other in the hydraulic oil.