JPS6230333B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates primarily to a hydraulic clutch interposed between a main engine and an output shaft system in a ship, and more particularly to a hydraulic clutch capable of controlling clutch operating oil pressure.

Fig. 1 shows the hydraulic circuit of the hydraulic speed reduction/reversing clutch for ships of the present invention (hereinafter simply referred to as the hydraulic clutch), but the hydraulic circuit of the conventional hydraulic clutch is different from the clutch operation of the hydraulic circuit shown in Fig. 1. In place of the hydraulic pressure regulating valve (hereinafter referred to as clutch pressure regulating valve) 22, a clutch pressure regulating valve 22' shown in FIG. 5 is used.

When the selector 21 is switched to normal rotation (or reverse rotation), the relationship between the clutch operating oil pressure and the engine speed becomes as shown by curves P ₁ , P _1c and P _c in FIG. 7.
However, the oil pump is assumed to be a displacement type such as a gear pump and driven by an engine at a constant rotation ratio.

Note that P _c (P _0c = P _1c = P _2c = P _3c = P _c ) is
This is the set pressure of the clutch pressure regulating valve 22'.

When the engine speed is extremely low, the discharge amount of the oil pump is small, so the oil pressure does not reach the set pressure P _c due to leakage from various parts, resulting in a P ₁ curve. If there is no leakage from any part, the hydraulic pressure will be the set pressure (P _0c = P _1c = P _2c = P _3c = P
_c ) becomes constant.

In FIG. 7, the H _s curve shows the relationship between engine speed and engine output during cruising, and the P _s curve shows the required hydraulic pressure for the clutch at that time. The H _B curve shows the relationship between engine speed and engine output during bollard operation (mooring operation), and the P _B curve shows the required hydraulic pressure for the clutch at that time.

Therefore, the output range of the marine engine of this example is below the curves _HB , _HB1 , and _HS1 , and the required hydraulic pressure for the clutch at that time is below the curves _PB , _PB1 , and _Ps1 . However, the hydraulic pressure of the clutch is curved P ₁ , P _1
c and _Pc , the oil pressure is too high than necessary at medium speeds or lower, especially at low speeds.

This is because the oil pump not only wastes power at medium speeds or lower, but also because the clutch oil pressure is high, the torsional rigidity of the clutch increases, causing the following serious problems.

That is, diesel engines and the like have large torque fluctuations at low speeds and correspondingly large rotational speed fluctuations, so if the torsional rigidity of the clutch is high, severe gear noise will be generated due to the speed fluctuations of the hydraulic clutch. This gear noise not only significantly worsens the ship's internal environment, but also damages the tooth surfaces of the gears due to their collision, and the vibrations generated due to torque fluctuations may loosen bolts, etc. in the engine and various parts of the ship's hull. , causing serious accidents such as cracks in pipes and cuts in electrical wiring.

Conventional countermeasures to this problem include reducing speed fluctuations at low speeds by using a very large flywheel,
Hydraulic couplings or special couplings were used to connect the engine to the engine, but this significantly increased weight and cost.

The present invention attempts to solve the above-mentioned problems and provides a hydraulically controlled hydraulic clutch which allows smooth operation even during low speed rotation.

Therefore, in the hydraulic clutch interposed between the engine and the output shaft system, the engine output is transmitted from the oil pump to the clutch operating hydraulic path leading to the clutch operating mechanism via the clutch operating hydraulic pressure regulating valve. A pressure oil release passage is provided to release the pressure oil to the clutch bearing lubricating oil system or drain tank through this pressure adjustment hole. It is characterized in that the pressure regulating throttle hole is arranged so that the oil release passage is always open when the engine is running at low speed.

That is, in the present invention, the relationship between the engine speed and the required oil pressure of the clutch is first determined from the relationship between the engine speed and the engine output, and then the relationship between the engine speed and the oil pump discharge amount is determined. The diameter of the throttle hole is required to ensure the required oil pressure.

Then, a throttle hole (pressure adjustment throttle hole) with the diameter determined by the above calculation is made in the clutch hydraulic pressure path, and at low speeds, the clutch hydraulic pressure is lowered to the necessary and sufficient hydraulic pressure to reduce the clutch slip torque and reduce the clutch slip torque. By slipping the clutch at peak torque and reducing clutch speed fluctuations, gear noise is prevented.

At medium speeds or lower rotation speeds, the clutch operating oil pressure becomes sufficient and the unnecessary power of the oil pump can be saved, resulting in savings in engine fuel consumption.

These measures can be taken without increasing costs and have the advantage of being easily applicable to existing hydraulic clutches.

Hereinafter, an embodiment in which the present invention is applied to a hydraulic speed reduction/reversing clutch for a ship will be explained with reference to the drawings. FIG. A clutch shaft 3 is driven from an output shaft 1 of a diesel engine (not shown) through a joint 2. A clutch box 4 and a reverse intermediate drive gear 5 are fixed to the clutch shaft 3 by shrink fit or the like, and a normal rotation drive gear 6 is rotatably supported.

A clutch box 8 and a reverse intermediate driven gear 9 are fixed to the reverse rotation shaft 7 by shrink fitting or the like, and a reverse rotation driving gear 10 is rotatably supported. Note that the reverse intermediate drive gear 5 and the driven gear 9 are in mesh with each other.

The reduction gear 11 is the forward rotation and reverse rotation drive gear 6,1
0, and is fixed to the reduction shaft 12 by shrink fit or the like. In addition, the propeller shaft 14 is connected to the joint 1
3 to the deceleration shaft 12.

In addition, the reference numeral 15 in the figure is an oil pump, 16 is an oil reservoir (drain tank), 17 is a strainer, and 18
19 is an oil pressure gauge, 19 is an oil cooler, 20 is a switching valve, 21 is a selector, 22 is a clutch pressure regulating valve (clutch operating oil pressure regulating valve), 25 is a pressure regulating hole provided in the clutch pressure regulating valve 22, and 23 is a lubricating oil pressure. A regulating valve (hereinafter referred to as a lubrication pressure regulating valve), 24 indicates a buffer throttle valve.

FIG. 2 shows details of the switching valve 20 shown in FIG.
9, inner spring 40, lubrication pressure regulating valve 41, same spring 42,
A buffer throttle valve 43, a spring 44, a throttle valve seat 45, a selector restraining lid 46, a pressure regulating valve restraining lid 47, and the like are attached.

Note that the clutch pressure regulating valve 22 shown in FIG.
The lubricant pressure regulating valve 23 shown in the figure is different from each member 41, 4 shown in FIG.
The buffer throttle valve 24 shown in FIG. 1 is made up of the members 43, 44, and 45 shown in FIG.

The oil discharged from the oil pump 15 flows through the inlet 35.
The pressure enters the switching valve main body 26, the pressure is regulated by the clutch pressure regulating valve 27, and the pressure is distributed by the selector 21. The pressure of the excess oil regulated by the clutch pressure regulating valve 27 is further regulated by the lubrication pressure regulating valve 41.
Sent to clutch bearing lubricant system. Lubrication pressure regulating valve 4
Excess oil whose pressure has been regulated in step 1 is discharged from an oil reservoir (drain tank) through a pressure oil release path from a discharge port 37 communicating with the pressure oil release path.

Figure 3 shows the clutch pressure regulating valve body 27 in Figure 2.
details. The clutch pressure regulating valve body 27 is
The body part 28, the collar part 29, and the inner spring guide part 30 are integrally formed, and the small hole 31 forming the pressure regulating orifice hole 25 shown in FIG. It is set up as follows.

In other words, when the pressure of the oil flowing into the switching valve body 26 from the inlet 35 is lower than the predetermined pressure,
The flange 29 of the clutch pressure regulating valve body 27 is connected to the inner spring 4.
0, it becomes energized. At this time, the position of the pressure regulating outlet 32 (the position of the clutch pressure regulating valve body 27 in the switching valve body 26 in the sliding axis direction) is set so that the pressure regulating outlet 32 fully communicates with the discharge side hole 36. has been done.

Furthermore, when the pressure of the oil supplied from the oil pump 15 exceeds a predetermined pressure, the clutch pressure regulating valve body 27 moves against the inner spring 40 and the outer spring 39 to force the switching valve body 2
6 to the left in the figure. Then, when the clutch pressure regulating valve body 27 moves by a predetermined distance,
The body end surface 33 of the clutch pressure regulating valve body 27 opens slightly into the discharge hole 36, and the oil flow path from the inlet 35 to the discharge hole 36 is established inside the clutch pressure regulating valve body 27 (that is, through the pressure regulating orifice). It connects directly without going through the hole 25). And almost at the same time,
The relative position of the pressure regulating discharge port 32 with respect to the body end surface 33 is set such that a portion of the pressure regulating discharge port 32 begins to be gradually closed by the wall portion forming the discharge side hole 36.

The pressure regulating outlet 32 and the small hole 31 communicate with each other to form the pressure regulating throttle hole 25.

Note that the area of the pressure regulating orifice hole 25 is calculated by means described later and set to a required size.

FIG. 4 shows a modification of the clutch pressure regulating valve body 27 of the present invention, in which the convex inner spring guide portion 3 of FIG.
0 is replaced by a concave inner spring guide portion 34, but the other structure is similar to the clutch pressure regulating valve body 27 of FIG. However, when using the clutch pressure regulating valve body shown in Fig. 4, an inner spring whose overall length is slightly longer than the inner spring 40 used in the pressure regulating valve body having the convex inner spring guide portion 30 shown in Fig. 3 is used. 40' must be used.

FIG. 5 is a schematic diagram of a conventional clutch pressure regulating valve 22', and FIG. 6 is a schematic diagram of a conventional clutch pressure regulating valve body 27'.
shows. As shown in the diagram, a conventional clutch pressure regulating valve body 2
7' is not provided with the pressure regulating orifice 25 or small hole 31 and the pressure regulating outlet 32 as in the clutch pressure regulating valve body 27 of the present invention shown in FIGS. 2-4.

FIG. 7 shows the relationship between the engine speed, engine output, and clutch operating oil pressure of a marine engine.

The relationship between the engine speed and the engine output during cruising is a curve _Hs , and the required oil pressure of the clutch at this time is a curve _Ps . Furthermore, the engine speed, engine output, and required oil pressure for the clutch at the time of bollarding are represented by curves H _B and P _B , respectively.

Therefore, the output range of the marine engine of this example is below the curves _HB , _HB1 , _Hs1 , and the required hydraulic pressure of the clutch is below the curves _PB , _PB1 , _Ps1 . For the actual clutch oil pressure, it is sufficient to provide a slight margin for the curves P _B , P _B1 , and P _s1 .

However, when a conventional clutch pressure regulating valve (as shown in Figs. 5 and 6) is used, the relationship between engine speed and clutch oil pressure is expressed by the curves P ₁ , P _1c , P _c (P _1c , P _c
is the pressure set by the clutch pressure regulating valve), and the oil pressure is excessive, especially at medium speeds or lower. Therefore, at medium speeds and below, the engine generates more hydraulic pressure than necessary, which not only causes the engine to generate wasted power and therefore wastes fuel, but also reduces the torsional rigidity of the clutch at medium speeds and below. Since the torque is high, intense gear noise is generated due to the collision of the tooth surfaces of the gears of the clutch due to engine torque fluctuations.

This gear noise not only significantly deteriorates the ship's environment, but also causes damage due to the collision of tooth surfaces of the gears, and the vibrations generated due to torque fluctuations may loosen bolts, etc. in the engine and various parts of the ship's hull, and cause damage to the gear teeth. This can lead to cracks in the electrical wiring and breakage of electrical wiring.
They also caused serious accidents and problems, such as causing electronic equipment such as fish finders to malfunction, and the noise causing schools of fish to scatter, resulting in a sharp drop in catches.

Below, a description will be given of means for setting the aperture area of the pressure regulating aperture hole 25 of this embodiment.

We will use a gear pump (displacement type), which is the most commonly used oil pump, and consider the engine speed and adjusted oil pressure in the case where it is driven at a constant rotation ratio with the engine.

Q=η・Vth・n/60=2πm ² zb×10 ⁻³ ×η
・n/60...(1) Q: Oil pump discharge amount (cm ³ /sec) Vth: 〃 (cm ³ /rev) (Vth=2πm ² zb×10 ^-3 ) m: Gear module z: Number of teeth b: Face width (mm) η: Volumetric efficiency (≒0.9) n: Rotational speed (rpm) The relationship between the flow rate and oil pressure when passing through cross-sectional area a is C: Flow coefficient (assumed = 0.7) a: Total cross-sectional area (cm ² ) a = a _L + a _T a _L : Area of leakage from pressure regulating valve (excluding throttle hole), selector, etc. a _T : Throttle hole area γ : Specific weight of oil (900Kg/m ³ = 0.9×10 ^-3
Kg/cm ³ ) P ₁ : Pressure before the throttle hole (Kg/cm ² ) P ₂ : Pressure after the throttle hole (Kg/cm ² ) However, in the case of the hydraulic clutch in this example, when the flow rate is small, P ₂ may be set to 0.

From equation (2) P ₁ - P ₂ = (Q/1033a) ² = (Q/1033 (a _L + a _T ) ² ... (4) From formulas (3) and (4), cross-sectional area a, flow rate Q, oil pressure (P ₁ -
P ₂ ) relationship can be understood.

In addition, since the flow rate Q is proportional to the rotation speed n from equation (1), the relationship between a, (P ₁ -P ₂ ), and n can be understood.

To determine a _L , the area of the pressure regulating valve, selector, and other places where oil leaks can be determined based on drawings, the difference in fitting dimensions of the actual product, etc.
Alternatively, if the curve P ₁ in FIG. 7 (when a conventional pressure regulating valve without a pressure regulating orifice is used) is obtained by actual measurement, it can be easily obtained from equation (3).

Next, find the oil pressure by multiplying the oil pressure at the minimum rotation speed of curve P _B (minimum oil pressure required for bollard) by an appropriate safety factor, and enter this into equation (3) (Q is the flow rate at the minimum rotation speed) When the cross-sectional area a is determined, the aperture hole area can be determined from a _T =a-a _L. According to this, the throttle hole area of the pressure regulating throttle hole 25 is set.

When this value is entered into equation (4) to find the relationship between rotational speed and oil pressure, curves P ₂ , P _2C , and P _C are obtained. This prevents gear noise at low speeds and reduces fuel consumption at medium speeds and below.

Furthermore, if we carefully compare the curves P ₂ , P _2C , P _C and P _B , P _B1 , P _S1 , we find that the safety factor in the medium speed range is too high compared to the safety factor in the low and high speed ranges. Recognize. If this safety factor in the medium speed range is lowered to a low level and lowered to that in the high speed range, the effect of reducing gear noise and fuel consumption will be greater.

In order to obtain this effect, the inner spring 40 and the outer spring 39
Set the spring force as follows.

When the oil pressure increases as the rotational speed increases (see Figures 2 and 3), the clutch pressure regulating valve body 27 compresses the inner spring 40 and the outer spring 39 and moves to the left in the figure, while the left end of the buffer piston 38 The same hydraulic pressure acts on the buffer piston 38 to move it to the right in the figure. At that time, if the spring forces of the inner and outer springs 40 and 39 are set so that the body end face 33 opens the discharge side hole 36 slightly, the leakage area will increase as the oil pressure increases, and the relationship between the rotation speed and the oil pressure will increase. are the curves P ₃ , P _3C , P
It becomes like _C.

In other words, even when the engine is running at low speed, the pressure regulating orifice 25
Since the pressure oil release path is always secured, as the engine speed increases from the low rotation range, the pressure of the pressure oil to the clutch increases slowly and smoothly, and the clutch pressure regulating valve The set pressure P _C of 22 is reached. As a result, this hydraulic characteristic is approximated by multiplying the curves P _B , P _B1 , P _S1 (required hydraulic pressure at bollard) by an appropriate safety factor, and prevents gear noise at low speeds and It is even more effective to reduce fuel consumption in the following cases.

In other words, since the slip torque of the clutch is small at low speeds, at the peak of engine torque fluctuations, the clutch momentarily slips a small amount and does not transmit the peak torque, so the clutch rotational fluctuations are reduced.
Prevents gear noise. Even in the medium-speed rotation range, the oil pressure is not too high but the necessary and sufficient oil pressure, so there is no wasted power wasted in the oil pump, and fuel consumption can be reduced.

According to the hydraulic clutch of the present invention, as described above, smooth operation can be obtained by an extremely simple means that does not involve an increase in cost, and gear noise that causes various serious problems is prevented, and fuel This also results in savings.

In the above-described embodiment, the pressure regulating throttle hole 25 was provided in the clutch pressure regulating valve body 27, but it is not necessarily necessary to provide it in the pressure regulating valve body 27. A similar effect can be obtained by providing a pressure regulating throttle hole in the path and opening it to the lubrication pressure regulating valve 41 or the drain tank.

However, since one type of hydraulic clutch is generally used in various engines, the area of the pressure regulating orifice must be changed if the rotational speed and output characteristics are different. In such a case, it is more advantageous in various respects to use pressure regulating valves with different throttle hole diameters.

A similar effect can also be expected by providing the pressure regulating orifice hole 25 (see Figure 1) in the hydraulic path from the clutch pressure regulating valve 22 to the forward and reverse clutch sections in the same manner as described above. It is difficult to adapt it to various engines with different rotational speeds and output characteristics.

Further, in these cases, since it is structurally difficult to introduce the oil after passing through the pressure regulating orifice into the lubrication pressure regulating valve 23, it may be drained. However, if this oil is drained, this oil cannot be used for lubrication. With this type of hydraulic clutch, the amount of oil pump discharged is small at low speeds, which may result in insufficient lubrication. Furthermore, when an automatic constant speed valve or a troll valve is used at low speeds to cause the clutch to slip, heat is generated due to the slipping of the friction plates, so insufficient lubricating oil may cause seizure. Also from this point of view, it is preferable to provide a pressure regulating throttle hole in the clutch pressure regulating valve.

[Brief explanation of the drawing]

Fig. 1 is a hydraulic circuit diagram showing a case where a hydraulically controlled hydraulic clutch as an embodiment of the present invention is applied to a speed reduction/reversing clutch for ships, and Fig. 2 is a hydraulic circuit diagram showing a clutch operation hydraulic pressure regulating valve in the hydraulic clutch of the present invention. FIG. 3 is a vertical cross-sectional view showing the detailed structure of the valve body of the regulating valve shown in FIG. 2, and FIG. 4 is a vertical cross-sectional view showing a modified example of the valve body of the regulating valve shown in FIG. FIG. 5 is a schematic diagram showing a conventional clutch operating hydraulic pressure regulating valve, FIG. 6 is an explanatory diagram showing the valve body of the conventional regulating valve, and FIG. 7 is a diagram showing the engine speed and speed of a marine engine. It is a graph showing the relationship between engine output and clutch operating oil pressure. 1... Output shaft of diesel engine, etc., 2... Coupling, 3... Clutch shaft, 4... Clutch box, 5...
...Reverse rotation intermediate drive gear, 6...Normal rotation drive gear, 7...
... Reverse shaft, 8 ... Clutch box, 9 ... Reverse intermediate driven gear, 10 ... Reverse drive gear, 11 ... Reduction gear, 12 ... Reduction shaft, 13 ... Coupling, 14 ... Propeller shaft, 15 ... ...Oil pump, 16...Oil sump (drain tank), 17...Strainer, 18...
...Oil pressure gauge, 19...Oil cooler, 20...Switching valve, 21...Selector, 22...Clutch pressure regulation valve (clutch operating pressure regulation valve), 23...Lubrication pressure regulation valve (lubrication pressure regulation valve), 24... ...Buffer throttle valve, 25...Pressure regulating throttle hole, 26...Switching valve body,
27...Clutch valve pressure regulating valve body, 28...Body part, 2
9...Brim part, 30...Inner spring guide part, 31...
Small hole, 32...pressure regulation outlet, 33...body end surface,
34...Inner spring guide part, 35...Inflow port, 36...
...Discharge side hole, 37...Discharge port communicating with pressure oil release path, 38...Buffer piston, 39...Outer spring, 4
0,40'...Inner spring, 41...Lubrication pressure regulating valve, 4
2... Spring, 43... Buffer throttle valve, 44... Spring, 45... Throttle valve seat, 46... Selector suppressing lid, 47... Pressure regulating valve suppressing lid.

Claims (1)

[Claims] 1. In a hydraulic clutch interposed between the engine and the output shaft system, the hydraulic power necessary to transmit the engine output to the clutch operating hydraulic path from the oil pump to the clutch operating mechanism via the clutch operating hydraulic pressure regulating valve. A pressure regulating orifice hole capable of reducing the pressure while leaving the oil pressure is provided, and a pressure oil release passage is provided through which the pressure oil is released to the clutch bearing lubricating oil system or a drain tank. A hydraulically controlled hydraulic clutch characterized in that the pressure regulating throttle hole is arranged so as to be always open when the engine rotates at low speeds.