JPH0547860Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a hydraulically actuated clutch device.

BACKGROUND TECHNOLOGY AND PROBLEMS Generally, in a vehicle equipped with a manual transmission, a clutch device is used to temporarily disconnect power transmission between the engine and the transmission during a gear change operation. By the way, this clutch device is, for example,
As disclosed in NISSAN Service Bulletin No. 442, hydraulically operated models are generally used, and the hydraulic pressure (hydraulic pressure) generated in the master cylinder when the clutch pedal is depressed is applied to the clutch via the clutch tube. The signal is transmitted to an operating cylinder provided on the unit side, and the operating cylinder disconnects the clutch unit.

As is generally known, in the clutch unit, power is transmitted by the clutch disk being pressed into contact between the flywheel and the pressure plate, and the power is transmitted by hydraulic pressure being supplied into the operating cylinder. , the pressure plate is separated from the clutch disk to cut off power transmission.

By the way, in such a hydraulic clutch device, when the clutch pedal is depressed to disengage the clutch, vibrations generated on the clutch unit side propagate the hydraulic fluid in the clutch tube from the operating cylinder to the master cylinder. The signal is input and transmitted from this master cylinder to the clutch pedal. especially,
The frequency of vibration input to the clutch pedal is
If the frequency is in the range of 200 to 400 (Hz), this vibration will be transmitted to the vehicle body through the clutch pedal support, causing an abnormal "go" noise and causing the clutch pedal itself to vibrate. This causes discomfort to the driver.

Therefore, as disclosed in the above-mentioned NISSAN Service Bulletin No. 442, a clutch damper is provided in the middle of the clutch tube to damp vibrations propagating within the clutch tube. However, in the case where a clutch damper is provided in this way, the structure of the clutch damper is complicated, resulting in an increase in cost, and when the clutch pedal is depressed, some fluid is also released into the clutch damper. There was a problem in that the stroke was increased due to the supply of pressure.

Therefore, the present invention provides a hydraulic clutch device that uses vibration resonance to solve the problems of the conventional clutch with a simple structure, and furthermore greatly improves the vibration damping effect. The purpose is to

Means for Solving the Problems In order to achieve the above object, the present invention is such that a master cylinder connected to the clutch pedal and an operating cylinder provided on the clutch unit are connected by a clutch tube, and when the clutch pedal is depressed, the master cylinder is connected to the clutch unit. Accordingly, in a hydraulic clutch device in which the clutch hydraulic pressure generated in the master cylinder is transmitted to the operating cylinder via the clutch tube to operate the clutch unit, the connecting portion of the clutch tube to the master cylinder is provided. A branch pipe that resonates in a special frequency range with the hydraulic vibration in the clutch tube is communicated nearby, and the branch pipe has a stepped shape in which the cross-sectional area of the terminal end is larger than that of the starting end. It is configured.

Effect With the above-described configuration, in the hydraulic clutch device of the present invention, by simply connecting the branch pipe to the clutch tube, a vibration impedance determined by the opening cross-sectional area and length of the branch pipe acts. hand,
Vibrations propagating within the clutch tube will be damped. Furthermore, by communicating the branch pipe near the connection portion of the clutch tube to the master cylinder, the vibration damping effect is significantly improved.

Embodiments Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 1 shows a hydraulic clutch device 10 according to an embodiment of the present invention. This hydraulic clutch 10 is used in a vehicle equipped with a manual transmission. A master cylinder 16 is connected to a clutch pedal 12 via a bushing 14.
When the pedal 2 is depressed, hydraulic pressure is generated in the master cylinder 16. Reference numeral 18 denotes an operating cylinder provided on the clutch unit side (not shown).
Withdrawal lever 20 of clutch unit
The operating cylinder 18 is connected to
When hydraulic pressure is supplied to the clutch disc 20, the withdrawal lever 20 is pressed, thereby releasing the pressure applied to the clutch disc by a pressure plate (not shown), thereby disengaging the clutch.

A clutch tube 22 for supplying hydraulic pressure is connected to the master cylinder 16, and the inside of the clutch tube 22 is further connected to a clutch hose 18a protruding from the operating cylinder 18, so that the hydraulic pressure generated in the master cylinder 16 is transferred to the clutch tube 22. The operating cylinder 18 is supplied via the tube 22.

Here, in this embodiment, the clutch tube 22
A branch pipe 30 that resonates with hydraulic vibrations within the clutch tube 22 in a specific frequency range is connected to the vicinity of the connection to the master cylinder 16 of the clutch tube 22 . The branch pipe 30 is a small diameter pipe 3 as shown in FIGS. 2 and 3.
The small diameter pipe 32 and the large diameter pipe 34 are liquid-tightly joined via a ring-shaped collar member 36. The proximal end of the small diameter tube 32 (the end opposite to the large diameter tube 34) is connected to an opening 2 formed in the clutch tube 22, as shown in FIG.
2a, and the terminal end of the large diameter pipe 34 (the end opposite to the small diameter pipe 32) is closed, so that the small diameter pipe 32 and the large diameter pipe 34 are filled with hydraulic fluid. It's getting old. Note that 38 is an air vent valve.

The functions of the hydraulic clutch device 10 of this embodiment with the above configuration will be described below.

That is, in this embodiment, by providing the branch pipe 30 in the clutch tube 22, the clutch pedal 1
2 to disengage the clutch, vibrations on the clutch unit side propagate through the hydraulic fluid in the clutch tube 22 and are transmitted to the master cylinder 16 and clutch pedal 12; Attenuation is provided by the branch pipe 30 during the propagation of the working fluid within the tube 22 . As shown in FIG. 5, compared to a straight branch pipe (in the case of an area ratio of 1), a branch pipe with a small diameter pipe 32 and a large diameter pipe 34 as in this embodiment has an area ratio of a>1. When it is attached, the total length of the branch pipe 30 can be shortened, and the amount of working fluid stored in the branch pipe 30 can also be reduced.

Therefore, it is better to use a stepped branch pipe 30 as in this embodiment, and the theory of vibration damping in this stepped branch pipe 30 will be analyzed below.

FIG. 6 shows a schematic diagram of the clutch tube 22. When force (pressure) F ₁ and velocity V 1 are applied to one end of the clutch tube 22, the force (pressure) _{F 2 and} velocity V generated at the other end are ₂ is expressed by the following equation, ignoring attenuation.

F ₁ V ₁ = cosβ jRcsinβ jRc ^-1 sinβ cosβF ₂ V ₂ … Here, Rc is the characteristic resistance of the tube and Rc = ρ.c (ρ:
density, c: speed of sound), β: phase constant, β = 2π/λ = ω/c, j = √-1.

For calculation purposes, if we consider force F as voltage v and speed V as current i, we can draw a model as shown in FIG. From this model, the clutch tube 22 and the master cylinder 1 of this clutch tube 22 are
When the small diameter pipe 32 of the branch pipe 30 connected in the vicinity of 6 has the same diameter, the following equations, equations, and equations can be obtained because the end of the branch pipe 30 is closed with a rigid wall.

v ₂ i _b = cosβ ₂ jRcsinβ ₂ jRc ^-1 sinβ ₂ cosβ ₂ v ₄ i ₄ (=0) … v ₂ i _a =1 jωL 0 1v ₃ (=0) i ₃ … From the formula, i _b = jRc ^-1 tanβ ₂ .v ₂ …′ From the formula i _a =v ₂ /jωL …′ From these′ and′ formulas i _b =jRc ^-1 tanβ ₅ .jωLi _a
is obtained.

On the other hand, v ₁ i ₁ = cosβ ₁ jRcsinβ ₂ jRc ^-1 sinβ ₁ cosβ ₁ v ₂ i ₂ (=i _a +i _b )..., and v ₁ i ₁ = cosβ ₁ jRcsinβ ₁ jRc ^-1 sinβ ₁ cosβ ₁ jωL. i _a [1-ωL.tanβ ₂ /Rc ₁ ] i _a ... is obtained.

Therefore, from this formula, when the “input” is force (pressure) excitation, v ₁ = [cosβ ₁ .jωL + jRcsinβ ₁ (1−ωLtanβ ₂ /Rc ₁ )] i _a … When the “input” is displacement excitation i ₁ = [−ωLRc ⁻¹ sinβ ₁ +cosβ ₁ (1−ωLtanβ ₂ /Rc ₁ )]i _a … are obtained respectively.

In other words, in any of these formulas, tanβ ₂
When =∞, i _a =0, that is, the vibration propagated to the master cylinder 16 side becomes "0".

By the way, the condition for tanβ ₂ = is β ₂ = π/2 + nπ (n = 1, 2, 3...). For example, when β ₂ = π/2, ₂ = π/2β = c/ω・π/ 2=
λ.f.π/2π.f.2=λ/4.

Therefore, the length of the small diameter pipe 32 is determined by the frequency in question,
In other words, by setting the frequency of the clutch's "go" sound to λ/4 of the generation frequency, this "go" sound can be prevented or significantly reduced.

In other words, when considered as vibration energy, this means that the impedance of the connection between the clutch tube 22 and the master cylinder 16 has become "0", and the traveling wave (input wave ) is totally reflected at the connection, meaning that the vibration energy is not transmitted to the master cylinder 16 side.

By the way, the vibration frequency range in which the "go" sound is generated is from 200 to 400 Hz, and it is desirable that the input impedance becomes "0" in this frequency range.In this embodiment, the branch pipe 30 is designed to satisfy this condition.
The length of is 0.3~0.7m, area ratio (1:a)=1:2~
1:5, stepped length ratio ( ₁ : ₂ ) = 2:1~1:
2 (see Figure 5).

As described above, in this embodiment, the branch pipe 30 is stepped, the various conditions are set as described above, and the clutch tube 22 is connected to the master cylinder 16 in the vicinity of the connection part. It is possible to obtain experimental results comparing this embodiment and the conventional method as shown in FIG. That is, Fig. 8 shows the vibration frequency on the horizontal axis and the sound pressure level and vibration acceleration amplitude level on the vertical axis.The sound pressure level is measured as front seat noise, and the characteristics (A) and ( Characteristics (b) and (b) are obtained when the conventional clutch is not used and when the clutch is not depressed.Characteristics (c) and (d) are obtained when the clutch is not used and when the clutch is not depressed in this embodiment. On the other hand, the vibration acceleration amplitude level is Clutch. The vibration perpendicular to the plane of the dash panel during off-state is expressed as the conventional characteristic (E) and the characteristic of this embodiment (F).
The left and right vibrations of the tip of the master cylinder 16 during the off-state are shown as a conventional characteristic (g) and a characteristic of this embodiment (h).

Therefore, the front seat noise shown in Figure 8 has the characteristics (A,
The hatched area between (b) and characteristics (c and d) indicates the "go" sound region transmitted through the clutch tube 22, which is significantly reduced in this embodiment. On the other hand, it is shown that the amplitude level of the present example is effectively reduced in the vibration frequency range of around 300 Hz for the darts panel surface normal vibration and the master cylinder tip lateral vibration.

Similarly, in Fig. 9, the horizontal axis represents the vibration frequency, and the vertical axis represents the vibration acceleration amplitude level acting directly on the clutch pedal 12 surface.
shows the result of this embodiment, and the effect of significantly reducing the clutch pedal normal vibration is particularly apparent in the vibration frequency range of 200 to 350 Hz.

Next, each function of this embodiment will be described for the case where the branch pipe 30 is connected to the vicinity of the master cylinder 16 side of the clutch tube 22, and with this configuration, the above-mentioned effects are particularly exhibited.
For example, the case where the branch pipe is provided on the operating cylinder 18 side of the clutch tube 22 will be compared with the case of this embodiment.

That is, the branch pipe is connected to the operating cylinder 18.
In the case where the branch pipe is provided on the master cylinder 16 side, a model as shown in FIG. 10 can be drawn in the same manner as the model shown in FIG. 7 where the branch pipe is provided on the master cylinder 16 side.

Therefore, from this model, v ₁ i _b = cosβ ₂ jRcsinβ ₂ jRc ^-1 sinβ ₂ cosβ ₂ v ₄ i ₄ (=0) … v ₁ i _a = cosβ ₁ jRcsinβ ₁ jRc ^-1 sinβ ₁ cosβ ₁ v ₂ i ₃ ... is obtained, and from the formula i _b = jRc ^-1 sinβ ₂ /cosβ ₂ . From v ₁ …′ equation and v ₂ = jωL.i ₃ , i _a = (cosβ ₁ −ωL.Rc ^-1 sinβ ₁ ). i ₃ …' is derived, and from the equation and v ₂ = jωL.i ₃ , v ₁ = (jωL.cosβ ₁ + jRcsinβ ₁ ). i ₃ ... is obtained.

Also, from the equations i ₁ = i _a + i _b and ′, ′, i ₁ = [(cosβ ₁ −ωLRc ⁻¹ sinβ ₁ )−Rc ⁻¹ tanβ ₂ . (ωLcosβ ₁ +Rcsinβ ₁ )]. i ₃ ... is obtained.

That is, the above equations correspond to the equations and equations in the case of the present embodiment, and these equations indicate that there is a vibration damping effect in the case of force (pressure) excitation and displacement excitation, respectively. Furthermore, the formula also shows that the effect appears with displacement excitation, but the formula shows that the effect does not appear with force (pressure) excitation. In other words, if the branch pipe is provided on the operating cylinder 18 side, the branch pipe does not function at all with respect to force (pressure) excitation.

Figure 11 shows the case where a conventional branch pipe is not provided.
When the branch pipe is provided on the operating cylinder 18 side and when the branch pipe is provided on the master cylinder 16 side.
In the case of the present embodiment, the horizontal axis represents the vibration frequency, and the vertical axis represents the vibration transmissibility, showing the characteristics (R, O, Wa) based on the experimental results. As is clear from this characteristic diagram, the vibration transmission rate decreases when a branch pipe is provided compared to the conventional one, and even more so when the branch pipe is provided on the operating cylinder 18 side. In comparison, it can be seen that the branch pipe of this embodiment provided on the master cylinder 16 side has a remarkable effect of reducing the vibration transmission rate.

Effects of the Invention As explained above, in the hydraulic clutch device of the present invention, a branch pipe is communicated with a clutch tube that connects a master cylinder and an operating cylinder, and the branch pipe is connected to a specified location within the clutch tube. Since the hydraulic vibrations in the frequency range are made to resonate, vibrations propagating through the working fluid in the clutch tube can be attenuated. By communicating with each other, the vibration damping effect can be significantly improved.
Therefore, when the clutch is disengaged or engaged, the vibration of the clutch unit that is input to the master cylinder and clutch pedal side via the hydraulic fluid in the clutch tube is damped before being input to the master cylinder, and the vibration of the clutch unit is damped before being input to the master cylinder. This has the excellent effect of being able to prevent or significantly reduce the occurrence of "go" noise and clutch pedal vibration, and greatly improve the ride comfort of the vehicle.

In addition, the hydraulic clutch device of the present invention has a branch pipe communicating with the clutch tube to damp hydraulic vibration within the clutch tube, which is different from the conventional method in which a clutch damper was provided in the middle of the clutch tube. The structure is much simpler than that of the previous one, and since the wall of the branch pipe does not change, there is an advantage that external vibrations are not propagated from the vibration damping part to the working liquid.

Furthermore, in the hydraulic clutch of the present invention, the branch pipe that communicates with the clutch tube has a stepped shape with a larger cross-sectional area at the terminal end than at the starting end, so the overall length of the branch pipe is shorter than that of a straight pipe. Another advantage is that it can be made shorter.

[Brief explanation of the drawing]

Fig. 1 is an overall perspective view showing an embodiment of the hydraulic clutch device of the present invention, Fig. 2 is an exploded enlarged perspective view of a branch pipe used in the present invention, and Fig. 3 is an exploded perspective view of a branch pipe used in the present invention. FIG. 4 is an enlarged sectional view of the joint between the clutch tube and branch pipe according to the present invention, FIG. 5 is a characteristic diagram according to the shape of the branch pipe, and FIG. 6 is a schematic diagram of the clutch tube according to the present invention. Fig. 7 is a model diagram dynamically showing the hydraulic clutch device of the present invention, and Fig. 8 shows the sound pressure level and vibration acceleration amplitude level of the hydraulic clutch device of the present invention compared to that of a conventional hydraulic clutch device. Figure 9 is a characteristic diagram comparing clutch pedal normal vibration in the hydraulic clutch device of the present invention with that of a conventional hydraulic clutch device, and Figure 10 is a characteristic diagram in which a branch pipe is provided near the operating cylinder. A model diagram corresponding to FIG. 7 in the case, and FIG. 11 are vibration characteristic comparison diagrams in the present invention. 10... Hydraulic clutch device, 12... Clutch pedal, 16... Master cylinder, 18... Operating cylinder, 22... Clutch tube, 30... Branch pipe, 32... Small diameter pipe, 34...
...Large diameter pipe.

Claims (1)

[Claim for Utility Model Registration] A master cylinder connected to the clutch pedal and an operating cylinder provided on the clutch unit side are connected by a clutch tube, and the clutch hydraulic pressure generated in the master cylinder when the clutch pedal is depressed is controlled. , transmitted to the operating cylinder via the clutch tube,
In the hydraulic clutch device configured to operate the clutch unit, a branch pipe that resonates in a specific frequency range with hydraulic vibrations within the clutch tube is connected to the vicinity of the connection portion of the clutch tube to the master cylinder, and A hydraulic clutch device characterized in that the branch pipe has a stepped shape in which the cross-sectional area at the terminal end is larger than at the starting end.