CN1539699A

CN1539699A - Oil locking means of front fork of bicycle

Info

Publication number: CN1539699A
Application number: CNA2003101201334A
Authority: CN
Inventors: 寺田正吾
Original assignee: Showa Corp
Current assignee: Showa Corp
Priority date: 2003-04-23
Filing date: 2003-12-08
Publication date: 2004-10-27
Anticipated expiration: 2023-12-08
Also published as: BR0306019A; CN100467340C; JP2004324750A; JP4036785B2

Abstract

In an oil locking device of a front fork of a motorcycle or the like, a piston valve 20 is provided on the inner periphery at the tip of an inner tube 12. An annular inner-periphery-side flow path 33 is formed between the inner periphery of the piston valve 20 and the outer periphery of a hollow rod 16. An annular outer-periphery-side flow path 34 is formed between the outer periphery of the piston valve 20 and the inner periphery of a inner tube 12. Annular valve seats 31 and 32 to which upper and lower end faces of the piston valve 20 contacts/retracts are provided on the inner periphery at the tip of the inner tube 12. The upper/lower valve seats 31 and 32 are provided with a flow path for communicating the outer-periphery-side flow path 34 to oil chambers 21 and 22, before the outer periphery of the hollow rod 16. Notches 20 A and 20B penetrating radially are formed on the upper and lower end faces of the piston valve 20.

Description

The oily locking device of the front fork of two-wheel car etc.

Technical field

The present invention relates to the oily locking device of the front fork of two-wheel car etc.

Background technology

The oily locking device of the front fork of two-wheel car etc., open as described in the clear 56-119789 (patent documentation 1) as Japan is real, disclosed technology is: the oilhole control stalk (oily latch fitting) of abolishing taper, base portion near hollow shaft 1, its sidewall axially on be arranged side by side the different aperture in a plurality of apertures 2, the piston body of pipe on the lower end successively these apertures 2 stopped up in utilization was arranged on, to the grease chamber of piston body bottom carrying out oil locking, the buffering when formation is compressed most.

In the oily locking device of patent documentation 1, when from compression stroke when stretching travel shifts, arrive at piston body before the aperture 2 of upper/lower positions, power fluid is supplied with insufficient in the oil lock grease chamber of piston body bottom, oil lock grease chamber forms negative pressure, when the aperture 2 that arrives upper/lower positions when piston body is opened this aperture, take place what is called uncork the bottle sound (take place when from bottleneck, extracting as the burgundy bottle stopper " bang " sound).

Summary of the invention

The object of the present invention is to provide the oily locking device of the front fork of a kind of two-wheel car etc., can abolish oily latch fitting, and prevent from when extended state shifts, producing the sound of uncorking the bottle from compressive state.

The oily locking device of the front fork of two-wheel car of the present invention etc., the interior pipe of body side with moving contact freely state be fitted in the outer tube of wheel side, bottom in outer tube erects to be provided with has in interior pipe the hollow stem of the wall part of moving contact on week, the grease chamber that the piston valve that week is provided with in interior pipe leading section is advanced and retreat in the periphery of hollow stem divides, interior week of hollow stem to top is divided as the trapped fuel chamber of energy chamber, the oilhole that above-mentioned grease chamber and trapped fuel chamber are communicated with is set in the bottom of hollow stem, it is characterized in that: above-mentioned piston valve is set in the leading section of pipe in above-mentioned in week, between the periphery of interior week of this piston valve and above-mentioned hollow stem, form interior all effluents road of ring-type, and the periphery of piston valve and above-mentioned in the outer circumferential side stream of formation ring-type between week in the pipe, upper and lower end face contact and the ring-type valve seat that separates with above-mentioned piston valve are set in the leading section of pipe in above-mentioned in week, the stream that setting makes above-mentioned outer circumferential side stream be connected with above-mentioned grease chamber between the periphery of up and down valve seat and above-mentioned hollow stem forms the notch of break-through diametrically in the upper and lower end face of above-mentioned piston valve.

Description of drawings

Fig. 1 is the overall section-drawing of expression front fork.

Fig. 2 is the section-drawing of the bottom section of expression front fork, (A) expression bottom amplification profile, (B) expression check valve (check valve) section-drawing on every side, (C) section-drawing around the expression piston valve.

Fig. 3 is the section-drawing of terminal stage of the compression stroke of expression front fork.

Fig. 4 is the section-drawing of incipient stage of the stretching travel of expression front fork.

Fig. 5 represents piston valve, (A) is section-drawing, (B) is birds-eye view, (C) is upward view.

Fig. 6 represents check valve, (A) is section-drawing, (B) is birds-eye view, (C) is upward view.

The specific embodiment

The front fork 10 of two-wheel car etc. as Fig. 1～shown in Figure 4, is fitted to the interior pipe 12 of body side in the outer tube 11 of wheel side with moving contact state freely.In the insertion of outer tube 11, on the open end of pipe 12, be provided with dust-proof seal ring 13 and oil sealing 14.

Inserting bolt 15 on the bottom of outer tube 11, utilize this bolt 15 to erect hollow stem 16 is set.To the upper end enlarged of hollow stem 16, week go up the wall part 17 of moving contact in the pipe 12 in being formed on.In the present embodiment, in the set circular groove 17A, the following check valve 40 that is made of piston ring is set on the periphery of next door portion 17, makes the moving contact on the interior week of interior pipe 12 of this check valve 40.

Between spring leaf 18 set on the upper end of the upper surface of the wall part 17 of hollow stem 16 and interior pipe 12, pendulum spring 19 has been installed.In the upper-end inner diameter portion of pipe 12,18B supported by locating ring in spring perch 18 was installed to by O shape ring 18A.

Front fork 10, piston valve 20 is set in the leading section of interior pipe 12 in week, the periphery of hollow stem 16 divide piston valve 20 advance and retreat on

lower oil chamber

21,22, interior all trapped fuel chambers 23 of dividing top as energy chamber 14 at hollow stem 16, in the bottom of hollow stem 16 oilhole 25 is set, oilhole 25 is communicated with

grease chamber

21,22 and trapped fuel chamber 23.The inside of pipe 12 in trapped fuel chamber 23 extends to, energy chamber 24 is by spring perch 18 sealings of the upper end of interior pipe 12.Break-through axially and on a plurality of positions of circumferencial direction at hollow shaft 16 is provided with oilhole 25.

In the leading section of interior pipe 12 on week, in valve housing 30 and ring-type valve seat up and down 31,32 are pressed abd fixed on the pipe 12, in the inside of valve housing 30, built-in can be on hollow stem 16 moving contact and the piston valve 20 that moves up and down.And piston valve 20 also can be fixed on above-below direction and can not move.And, between the periphery of interior week of piston valve 20 and hollow stem 16, form interior all effluents road 33 of ring-type, and, in the periphery of piston valve 20 with between the interior week of interior pipe 12 (being the interior week of valve housing 30 in the present embodiment), formed the outer circumferential side stream 34 of ring-type.

In week in the front of pipe 12 in

valve seat

31,32 up and down is arranged on, the end face up and down of piston valve 20 is in contact with one another or separates.Upper valve base 31 and the periphery of hollow stem 16 between form stream 31A, all effluents road 33 in being used to make, hit effluent road 34 outward and be connected with upper chamber 21.Lower valve base 32 and the periphery of hollow stem 16 between form under stream 32A, all effluents road 33, outer circumferential side stream 34 are connected with lower oil chamber 22 in being used to make.

Piston valve 20 on the end face up and down that contacts with up and down

valve seat

31,32 or separate, is formed on the 20A of notch up and down, the 20B that radially connect as shown in Figure 5.

Check valve 40 is made of the C word shape piston ring that can move up and down on the circular groove 17A that is provided with on the periphery of the wall part 17 of hollow stem 16, moving contact on the interior week of interior pipe 12, and, and the trench bottom of circular groove 17A between form ring-type stream 41.Check valve 40 as shown in Figure 6, on the circular groove 17A of next door portion 17, with lower surface that the following side channel side wall portion of upper chamber 21 is connected on, be formed on the notch 40A that radially connects.Check valve 40 is when (a) compression stroke, move down (along with interior pipe 12 and hollow stem 16 carry out relative move down and moving down), open valve forming the gap between the side channel side wall portion on the circular groove 17A of the upper surface of this check valve 40 and wall part 17, the power fluid of the trapped fuel chamber 23 on the top of permission wall part 17 is by ring-type stream 41, notch 40 and flowing in the upper chamber 21 of periphery of hollow stem 16, when (b) stretching travel, move up (because the pressure of the oil of upper chamber 21 raises, and interior pipe 12 moving up with respect to hollow stem 16, and move up), make the last side channel side wall portion of the circular groove 17A of the upper surface of this check valve 40 and wall part 17 combine closely valve-off, stop the power fluid of the upper chamber 21 of hollow stem 16 peripheries to flow in the trapped fuel chamber, top 23 of wall part 17.

Front fork 10 is provided with the oilhole (aperture) 26 that upper chamber 21 and trapped fuel chamber 23 are communicated with on hollow stem 16, when stretching travel, utilize this oilhole (aperture), based on from the passage resistance of upper chamber 21 to the oil of trapped fuel chamber 23 outflows, produces the tensile side attenuation power.

And, in front fork 10, between the wall part 17 of upper valve base 31 that is provided with on the interior pipe 12 and hollow stem 16, the rebound spring 27 when being provided with maximum tension.

On front fork 10, utilize the air bellow of pendulum spring 19 and energy chamber 24 to come that suffered impact absorbs and cushions to wheel, follow the stretching vibration of the pendulum spring 19 that the absorption of this impact is produced, the attenuation powers control that is produced in the

grease chamber

21,22.

That is to say front fork 10 attenuations that play as described below.

[compression stroke]

If interior pipe 12 enters in the

grease chamber

21,22 of periphery of hollow stem 16, the increased pressure of the lower oil chamber 22 of the bottom of the piston valve 20 that dwindles of volume then.Piston valve 20 is moved upward, join with upper valve base 31, the power fluid of the lower oil chamber 22 of the bottom of piston valve 20 flows in the upper chamber 21 by interior all effluents road 33 of piston valve 20, in addition, by by the stream that forms between the notch 20A of the upper surface of the outer circumferential side stream 34 of piston valve 20, piston valve 20 and the upper valve base 31, flow into upper chamber 21, produce the compressed side attenuation power.

And, because the volume of the upper chamber 21 on the top of piston valve 20 enlarges, pressure reduces, so, the check valve 40 that is provided with on the wall part 17 of hollow stem 16 is opened, and the power fluid of the trapped fuel chamber 23 on the top of wall part 17 flows in the upper chamber 21 by ring-type stream 41, the notch 40A of check valve 40.

And the power fluid of the volume in quantity is equivalent to enter in the

grease chamber

21,22 of pipe 12 by a plurality of oilholes 25 that the bottom at hollow stem 16 forms, flows into the trapped fuel chamber 23 in the interior week of hollow stem 16 from lower oil chamber 22.Produce the compressed side attenuation power at a plurality of oilholes 25 places.

If piston valve 20 stops up a plurality of oilholes 25 of the bottom of hollow stem 16 successively, enter the terminal stage of compression stroke, then as shown in Figure 3, the power fluid of the lower oil chamber 22 of the bottom of piston valve 20 (the oil lock 22A of grease chamber), only by by interior all effluents road 33 of piston valve 20 and outer circumferential side stream 34, in the stream that forms between the notch 20A of the upper surface of piston valve 20 and the valve seat 31, inflow upper chamber 21.Its result, the flow path area that leads to the power fluid of upper chamber 21 from the oil lock 22A of grease chamber reduces and becomes oily lock state, and the increase of compressed side attenuation power is to rushing in row buffering in the end of outer tube 11 and interior pipe 12.

[stretching travel]

If from the end of outer tube 11 and interior pipe 12 towards state transitions to stretching travel, then as shown in Figure 4, piston valve 20 moves downwards, joins with lower valve base 32.The power fluid of the upper chamber 21 on the top of piston valve 20, by by formed stream between the notch 20B of the lower surface of interior all effluents road 33 of piston valve 20 and outer circumferential side stream 34, piston valve 20 and the lower valve base 32, flow into the oil lock 22A of grease chamber of the bottom of piston valve 20, successfully separate the negative pressure of the oil removing lock 22A of grease chamber, prevent the sound of uncorking the bottle when stretching travel shifts.

Moreover, if piston valve 20 rises, the power fluid of the upper chamber 21 on piston valve 20 tops then, formed stream between the notch 20B of the lower surface of interior all effluents road 33 by piston valve 20 and outer circumferential side stream 34, piston valve 20 and the lower valve base 32, lower oil chamber's 22 displacements to the bottom of piston valve 20 are flowed, in addition, by the oilhole (aperture) 26 that is provided with in hollow stem 16 top break-through, flow to the trapped fuel chamber 23 in week in the hollow stem 16.At interior all effluents road 33, outer circumferential side stream 34 and the oilhole (aperture) 26 of piston valve 20, produce the tensile side attenuation power.And, can there be oilhole (aperture) yet.

If adopt present embodiment, then produce following action effect.

1. at front fork 10, in the oily locking device of the buffering usefulness when compressing most, can abolish oily latch fitting, and, from compressive state when stretching travel shifts, because the existence of interior all effluents road 33 of piston valve 20, outer circumferential side stream 34, notch 20B so can successfully eliminate the negative pressure of the oil lock 22A of grease chamber, prevents the sound of uncorking the bottle.

2. under the oil lock state of the compression stage of front fork 10, the power fluid of the oil lock 22A of grease chamber by the stream that the notch 20A by the upper surface of interior all

effluents road

33,34 of piston valve 20, piston valve 20 constitutes, flows in the upper chamber 21 on top of piston valve 20.

So, the stream that the notch 20A of piston valve 20 upper surfaces forms, must set for and be used to carry out the required enough little sectional area of oil lock, but if reduce notch 20A, then when common compression stroke, when the power fluid of the lower oil chamber 22 of the bottom of piston valve 20 when upper chamber 21 displacements on top are flowed, notch 20A plays nozzle (orifice) effect, upper chamber 21 is easy to generate negative pressure.

Therefore, in the present invention, the check valve of opening when on the wall part 17 of hollow stem 16, compression stroke being set 40, the upper chamber 21 on piston valve 20 tops produces negative pressure in the time of preventing compression stroke.Yet, not necessarily check valve 40 to be set, piston ring also can be set replace check valve 40, in this case, the trapped fuel chamber 23 on wall part 17 tops and the grease chamber 21 of bottom also become unconnected during arbitrary stroke in compression stroke and stretching travel.

And in piston valve 20, the flow path area on interior all effluents road 33 that piston valve 20 forms is less than the flow path area of each

notch

20A, 20B formation.

Below with reference to the accompanying drawings, describe embodiments of the present invention in detail, still, concrete structure of the present invention is not limited only to this embodiment, and design-calculated change without departing from the spirit and scope of the present invention etc. is also contained in the present invention.

If adopt the present invention, then in the oily locking device of the front fork of two-wheel car etc., can abolish oily pin member, and can prevent from the compressive state sound of when stretching travel shifts, uncorking the bottle.

Claims

1, the oily locking device of the front fork of a kind of two-wheel car etc.: the interior pipe of body side with moving contact freely state be fitted in the outer tube of wheel side, bottom in outer tube erects to be provided with has in interior pipe the hollow stem of the wall part of moving contact on week, the grease chamber that the piston valve that week is provided with in interior pipe leading section is advanced and retreat in the periphery of hollow stem divides, interior week of hollow stem to top is divided as the trapped fuel chamber of energy chamber, in the bottom of hollow stem the oilhole that above-mentioned grease chamber and trapped fuel chamber are communicated with is set, it is characterized in that:

Above-mentioned piston valve is set in the leading section of pipe in above-mentioned in week, between the periphery of interior week of this piston valve and above-mentioned hollow stem, form interior all effluents road of ring-type, and the periphery of piston valve and above-mentioned in the outer circumferential side stream of formation ring-type between week in the pipe, upper and lower end face contact and the ring-type valve seat that separates with above-mentioned piston valve are set in the leading section of pipe in above-mentioned in week, the stream that setting makes above-mentioned outer circumferential side stream be connected with above-mentioned grease chamber between the periphery of up and down valve seat and above-mentioned hollow stem forms the notch of break-through diametrically in the upper and lower end face of above-mentioned piston valve.

2, the oily locking device of the front fork of two-wheel car as claimed in claim 1 etc., it is characterized in that: the periphery of the wall part that has at above-mentioned hollow stem is provided with check valve, described check valve is opened valve when compression stroke, allow power fluid to flow into the grease chamber of above-mentioned hollow stem periphery from the trapped fuel chamber on this wall part top, and, valve-off when stretching travel prevents that power fluid from flowing to the trapped fuel chamber on this wall part top from the grease chamber of this hollow stem periphery.

3, the oily locking device of the front fork of two-wheel car as claimed in claim 1 etc. is characterized in that: above-mentioned oilhole is arranged on axially and on a plurality of positions of circumferencial direction of hollow stem bottom.

4, the oily locking device of the front fork of two-wheel car as claimed in claim 1 etc. is characterized in that: the above-mentioned lower valve base of going up carries out clamping to valve housing, in being pressed abd fixed on the pipe.

5, the oily locking device of the front fork of two-wheel car as claimed in claim 1 etc. is characterized in that: be provided with oilhole on above-mentioned hollow stem, be used for being communicated with the grease chamber and the above-mentioned trapped fuel chamber of the wall part side of the grease chamber that is divided into by above-mentioned piston valve advance and retreat.

6, the oily locking device of the front fork of two-wheel car as claimed in claim 1 etc. is characterized in that: on the pipe between the wall part of set upper valve base and above-mentioned hollow stem, be provided with the rebound spring in above-mentioned.

7, the oily locking device of the front fork of two-wheel car as claimed in claim 2 etc., it is characterized in that: above-mentioned check valve is made of the piston ring of C word shape, and this piston ring can be installed in the circular groove set on the periphery of wall part of above-mentioned hollow stem up or down.