JPS6364663B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a slip control device for a reduction gear with a hydraulic friction clutch.

Conventionally, in mechanisms that have a hydraulic friction clutch, such as marine reversing speed reducers, when the friction clutch does not slip, the propeller rotation speed is only the minimum rotation that is the ratio of the engine idle rotation to the reduction ratio. do not have. Therefore, when fishing operations require even lower rotation, the friction clutch is slipped to obtain an extremely low speed.

Conventionally, this slip control includes a method in which a rotation detector is provided on the propeller shaft and the signal is fed back to control the oil pressure, and a method in which the oil pressure is unilaterally adjusted using a hydraulic control valve. However, although the former method has the advantage that it is easy to obtain constant rotation, it has the disadvantage that the device is complicated and expensive. On the other hand, conventional systems based on the latter method are inexpensive, but the oil pressure tends to change due to the temperature of the hydraulic oil, which changes over time. Also, due to the addition of hydraulic vibrations, constant rotation cannot be obtained, so the oil pressure is frequently changed. The disadvantage was that the control relay had to be adjusted.

For example, FIG. 1 shows the origin circuit of this latter slip control device, where 101 is an oil path leading from the pump and main oil pressure regulating valve, 102 is a throttle, and 103 is an oil line connecting the throttle 102 and the forward/reverse switching valve 104. Road, 1
Reference numeral 05 designates a needle valve, which lowers the oil pressure in the oil passage 103 by moving the needle valve 105 up and down in the direction of the arrow. In this case, even if the area of the opening 106 of the needle valve 105 is kept constant, the oil pressure in the oil passage 103 will change significantly due to changes in the viscosity of the hydraulic oil due to changes in oil temperature.

Similarly, FIG. 2 shows a case where a low pressure oil pressure regulating valve is provided in place of the needle valve 105, and 108
is a valve, 109 is a spring, the pressing force of the spring 109 is changed in the direction of the arrow, and the valve 10 is
8, the hydraulic pressure in the chamber 107 is balanced and the clutch hydraulic pressure reaching the oil passages 103 and 103' is adjusted. However, due to the dynamic flow in the opening 106, the oil pressure in the chamber 107 fluctuates, and the valve 108 tends to vibrate.
Further, since there is some hydraulic leakage from the forward/reverse switching valve 104, the hydraulic pressure in the chamber 107 does not necessarily match the hydraulic pressure in the oil passages leading to the oil passages 103 and 103'. That is, all of the above-mentioned conventional examples still have problems with hydraulic vibration and viscosity effects, and stable adjusted hydraulic pressure cannot be obtained.

The present invention has been made in view of the above circumstances, and is intended to improve the drawbacks of the latter method of unilaterally adjusting the hydraulic pressure in a hydraulic control valve, and is intended to improve the problem of hydraulic pressure changes due to hydraulic oil temperature and hydraulic vibration. The present invention aims to provide a slip control device which can obtain a constant slip rate under a constant low oil pressure corresponding to the control lever position.

That is, the present invention provides a reversing speed reducer equipped with a hydraulic friction clutch, in which a differential valve that operates only when a slip occurs is connected to the oil path leading from the reverse switching valve of the speed reducer to the clutch via a check valve, thereby reducing errors. The valve train has an oil chamber with a large pressure receiving area, an opposing oil chamber with a small pressure receiving area, and a throttle oil passage communicating with these oil chambers.
It includes a spring that adjusts the differential pressure between the two oil chambers, and an oil passage leading to a drain, and the oil passage leading to the drain is connected to the forward/reverse switching valve through an opening that is adjusted along with the movement of the differential valve. Conducts all oil passages,
Furthermore, a control lever is provided for changing the pressing force of the spring, and a switching valve is provided which switches between normal operation and slip operation using the control lever, and is linked to the differential valve to switch forward and backward movement. This is a slip control device for a reversing speed reducer, which is characterized by controlling the oil pressure before the valve.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 3 shows the basic structure of the low pressure regulating valve according to the present invention, in which 108 is a differential valve, 109 is a spring, 107 and 111 are oil chambers, and 110 is a throttle that communicates between oil chambers 107 and 111. Oil road, 11
0' is an oil passage that conducts the oil passage 103 to the drain side, 1
Reference numeral 12 denotes an oil passage leading from the forward/reverse switching valve 104 to the oil chamber 107. Components having the same configuration as those of the prior art example are given the same reference numerals, and the description thereof will be omitted.

First, the oil pressure in the oil passage 103 is controlled by the forward/reverse switching valve 10.
4, it is divided into an oil passage 103' and an oil passage 112 leading to the clutch. Oil chamber 107 from oil passage 112
The hydraulic pressure guided to the oil chamber 107 is guided to the oil chamber 111, which has a smaller area than the oil chamber 107, through the throttle oil passage 110.
The pressing force of the spring 109 acts on the differential valve 108 so as to balance the oil pressure corresponding to the ratio of the difference in the pressure receiving area between the pressure receiving area 07 and the oil chamber 111. and differential valve 108
In response, the opening area of the opening 106 is adjusted and the oil pressure of the oil passage 103 is changed, and the resulting oil pressure of the oil passage 103' leading to the clutch is sensed as a static pressure through the oil passage 112 and is adjusted to a predetermined level. It is designed to maintain pressure.

FIG. 4 shows a hydraulic control circuit in which the present invention is applied to a marine reversing speed reducer. 1 is an oil pan that stores oil that serves as a hydraulic pressure source; 2 is a strainer; 3 is a pump that pressurizes the oil from the oil pan 1 to generate hydraulic pressure; 4 is a cooler that adjusts the pressurized oil to a predetermined temperature; Reference numeral 5 indicates a main hydraulic pressure regulating valve, and 6 indicates a backup piston provided in the main hydraulic pressure regulating valve 5. This main hydraulic pressure regulating valve 5 regulates the main hydraulic pressure generated by the pump 3 to a predetermined pressure (see Patent No. 1306873). . Further, 7 is a lubricating oil pressure regulating valve that adjusts the oil pressure sent to the lubricating circuit of each part, and 8 is an accumulator. This accumulator 8 is equipped with a throttle to reduce the impact when the clutch is operated. Furthermore, 9, 11, 13 and 14 indicate oil passages, and when oil pressure is applied to the backup piston 6 through the oil passage 14, the main oil pressure is increased through the oil passage 9 by the main oil pressure regulating valve 5. It's summery. If the oil passages 9 and 11 and the oil passages 14 and 12 are directly connected, it becomes a normal hydraulic control circuit, but the present invention separates these oil passages 9 and 11 and oil passages 14 and 12, and connects them with broken lines. A surrounding structure is interposed between these oil passages.

In Figure 4, the forward/reverse switching valve 10 is set to neutral,
This shows the normal state without slip control. 18 is a differential valve, 20 is a control lever, 22 is a switching valve, and 19 is a spring. control lever 2
0, the switching valve 22 is switched, and at the same time the spring 19 biasing the differential valve 18 is activated.
This changes the pressing force. 24 is a check valve, and 25 is a spring that biases it.
16 and 17 are a differential valve 18 and a check valve 24
An oil passage 23 is an oil passage for pressing and switching the check valve 24 through the switching valve 22.
The oil passage 9 communicates with a check valve 24 and a switching valve 22, respectively, and the oil passages 11, 12 and 14 communicate with the check valve 24, respectively. 13 and 15 are apertures. q, a~i, and a'~i' correspond to the respective ports provided in the check valve 24, and J~l and J'~
l' indicates each port provided in the switching valve 22, and m and n indicate ports provided in the differential valve 18, respectively.

FIG. 4 shows the state in which the forward/reverse switching valve 10 is in the neutral state as described above, and the oil pressure in the oil passage 14 is drained from the forward/reverse switching valve 10 via the oil passage 12. Therefore, since the backup piston 6 is set with a weak biasing force, the main oil pressure regulating valve 5 is relieved at a low pressure. Therefore, this low-pressure oil pressure passes through the ports J and k of the switching valve 22 from the oil path 9, passes through the oil path 23, and reaches the port q of the check valve 24, and the spring 2
After overcoming the pressure of step 5, insert check valve 2 in the position shown in the figure.
4 is set. It also branches off from the oil path 9 and passes through ports i, e, and d of the check valve 24 to the oil path 1.
The hydraulic pressure reaching 1 is stopped by the forward/reverse switching valve 10.

Next, a case where the forward/reverse switching valve 10 is switched to forward or reverse will be described. First, the oil pressure in the oil passage 9 is distributed through the ports i, d and i, e of the check valve 24, from both the throttles 15, through the oil passage 11, and from the forward/reverse switching valve 10 to the forward or reverse clutch. At the same time, the oil pressure in the oil passage 9 is guided from the forward/reverse switching valve 10 to the oil passage 14 via the oil passage 12, the ports g and b of the check valve 24, and the throttle 13, and the main oil pressure regulating valve 6 is controlled by the backup piston 6. energize the spring. Therefore, at the same time as the main oil pressure is increased, it is also communicated to the accumulator 8, and the throttle acts to relieve the switching shock. In addition, at this time, differential valve 1
Since the oil passages 16 and 17 leading to the check valve 24 are drained from ports c, h and ports a, f of the check valve 24, no hydraulic pressure is applied thereto.

Now, when the control lever 20 is rotated by a predetermined angle, the switching valve 22 is switched, as shown in FIG. 5, and the oil passage 9 is blocked at the port J'. At the same time, the oil pressure in the oil passage 23 is applied to the port k' of the switching valve 22,
l', and the check valve 24 is therefore switched to the illustrated state by the pressing force of the spring 25. Therefore, the oil pressure in the oil passage 14 is drained through ports b' and f' of the check valve 24, so the oil pressure in the main oil pressure regulating valve 5 is weakened, and oil pressure with this base pressure is supplied to the oil passage 9. Ru. Therefore, this oil pressure is led from the oil passage 9 to the oil passage 11 via the ports i' and e' of the check valve 24 and the throttle 15, and is then transferred from the forward/reverse switching valve 10 to the forward or reverse clutch (FIG. 5 shows the forward clutch). ). At the same time, the oil pressure in the oil passage 11 is led from the oil passage 16 to the port n of the differential valve 18 via ports d' and c' of the check valve 24, and is regulated. This pressure regulation standard oil pressure is determined by the clutch oil pressure in the oil passage 12 being guided from ports g' and a' of the check valve 24 through the oil passage 17 to the port m of the differential valve 18, and by the operation of the control lever 20. This is obtained by matching the pressing force of the spring 19 that changes as the pressure changes.

6 and 7 show embodiments embodying the present invention, with FIG. 6 corresponding to FIG. 4 and FIG. 7 corresponding to FIG. 5, respectively.

In FIG. 6, the switching valve 22 is connected to the control lever 20.
is configured to be rotatable relative to the valve body 21 by
An oil passage 44 is provided that communicates with ports J and k provided in the valve body 21. The spring 19 is the valve body 21
a spring seat 41 slidably disposed within the spring seat 41;
and the valve 33. The spring seat 41 is connected to the switching valve 22 by a pin 46,
It moves left and right according to the rotation of the switching valve 22, and is provided with an oil passage 43. The oil chambers 36 and 37 are connected to the valve 3
3 through a throttle oil passage 35 provided at 3. The valve 33 is provided with an annular groove 34 that opens and closes with respect to port n of the valve body 21 and an oil passage 38, which communicate with the port l of the valve body 21 through an oil chamber 42 and an oil passage 43. 39 is a sleeve that guides the valve 33 and the spring seat 41.

The check valve 24 includes a sliding spool 27 and a check piston 28 inside the valve body 26.
A spring 25 is interposed between the washer 31 that is engaged with a part of the valve body 26 and the spool valve 27,
The spring 25 constantly biases the spool valve 27 to the left in the figure, and the check piston 28 is similarly biased via a bolt 30 provided at the end of the spool valve 27. The valve 27 has a through hole 32 in the center, and an annular groove 48 leading to each port.
49, 50 and 51. 29 indicates an oil chamber. Moreover, 32a and 32b are conduction holes that penetrate the wall portion from the outside of the spool valve 27 and communicate with the through hole 32, respectively. Note that the other ports, oil passages, etc. are as shown in FIG. 4, and their explanation will be omitted.

In FIG. 6, when the control lever 20 is operated within the range indicated by arrow R, the oil passage 44 of the switching valve 22 communicates with the oil passage 9 and the oil passage 23 through ports J and k, and the oil chamber 36 The oil pressure is port m, oil path 1
7. Port a of check valve 24, conduction hole 32a,
The water is drained from ports f&h through the through hole 32. Therefore, the switching valve 22, the differential valve 18, and the check valve 24 are in the state shown, and the slip control function is not activated.

Now, after switching the forward/reverse switching valve 10 to forward,
When the control lever 20 is rotated in the range indicated by the arrow S shown in FIG. It is drained from line 23 through ports k and l. Therefore, the spool 27 and check piston 28 are moved to the left in the figure by the pressing force of the spring 25 of the check valve 24. The spool valve 27 of the check valve 24 is moved to the position shown;
Therefore, the oil pressure in the oil passage 14 is transferred from port b to the through hole 32.
The water is drained from port f (and h) provided at the right end. Therefore, the weakened hydraulic pressure is distributed from oil passage 9 through ports i, e and oil passage 11 to the forward/reverse switching valve 10 to the forward clutch. At the same time, oil line 11
The hydraulic pressure is led from ports d and c of the check valve 24 through the oil passage 16 to the port n of the differential valve 18, and is drained from the port l through the oil passage 38, the oil chamber 42, and the oil passage 43. On the other hand, the oil pressure in the oil passage 12 passes through the oil passage 17 from ports g and a of the check valve 24, passes through the port m of the differential valve 18, and is guided to its oil chamber 38, thereby moving the valve 33 to the left in the figure. . The oil pressure is further guided to the oil chamber 37 via the throttle oil passage 35. Therefore, the pressing force of the spring 19 acts on the valve 33 so as to balance the oil pressure corresponding to the ratio of the difference in pressure receiving area between the oil chamber 36 and the oil chamber 37. Then, the valve 33 stops at the balanced position, and the annular groove 34 of port n
The opening degree at is determined, and an appropriate reference oil pressure is obtained.

8 to 11 show the relationship between the operating angle of the control lever 20 and the movement positions of the switching valve 22 and the differential valve 18. 9 shows the initial stage of switching the control lever, FIG. 10 shows the state at intermediate low pressure, and FIG. 11 shows the state at the lowest pressure.

FIG. 12 is a diagram showing the relationship between the operating position of the control lever 20 shown in FIGS. 8 to 11, the clutch oil pressure, and the slip ratio.

As described above, according to the present invention, the hydraulic pressure at the widest part of the friction clutch after the forward/reverse switching valve is applied to the oil path 12.
The static pressure is guided to the differential valve 18 via the check valve 24 and sensed, and the hydraulic pressure before the forward/reverse switching valve is thereby controlled and supplied to the clutch, so that changes in temperature, etc. The influence of viscosity caused by In addition, the differential valve that adjusts this oil pressure is configured to have an oil chamber with a difference in pressure receiving area via the valve, and a throttle oil passage that connects both chambers to the valve, so a damper effect can also be obtained. , hydraulic vibration, valve chatter, etc. are also significantly improved.

Further, according to the present invention, a slip control lever is provided separately from the forward/reverse switching lever, and switching between normal operation and slip operation is performed at the turning stage of the operating angle of the lever, and stepless operation is performed at the latter stage. The clutch oil pressure can be controlled according to the position of the control lever, and a constant slip rate corresponding to the position of the control lever can be obtained under a constant low oil condition.

Further, according to the present invention, the slip control device itself can be downsized, and since it is an additional mechanism with only an oil path circuit, it can be installed later on a general reversing speed reducer as necessary.

Another feature is that this low-pressure relief valve (differential valve) structure has excellent relief characteristics in conjunction with the throttle 15, so the influence of the pump oil amount, which increases with engine speed, is minimal. It is possible to maintain a low pressure depending on the lever angle. Therefore, since the clutch surface pressure is guaranteed, there is no risk of the clutch seizing up even if the engine speed is accidentally increased during slip operation.

In addition, Fig. 13 is an application example of a differential valve, and the small oil chamber 3
By throttling the hydraulic pressure of 7 and draining it by adding 52, there is an effect of allowing the influence of viscosity within a certain range and speeding up the operational response of the valve 33.

Further, in FIG. 14, the valve is not a differential type but a direct acting type, and although problems remain with hydraulic vibration and valve chatter, the influence of viscosity can be sufficiently guaranteed.

Furthermore, FIG. 15 shows an advanced application example of the structure of the present invention, in which a solenoid valve 53 is added between the oil path 16 leading from the check valve 24 to the differential valve. Since the oil passage 16 is momentarily throttled, the relief performance of the differential valve 18 is inhibited, and the oil pressure from the oil passage 11 to the clutch is momentarily increased to approach the oil pressure in the oil passage 9. Therefore, it is possible to move the lead in increments as necessary during slip operation.

[Brief explanation of drawings]

1 and 2 are structural explanatory diagrams of a conventional slip control device, FIG. 3 is an explanatory diagram of the principle of the present invention, and FIG.
The figure shows a hydraulic control circuit diagram when the present invention is applied to a marine reversing speed reducer, with the forward/reverse switching valve in the neutral state, and Figure 5 is the same circuit diagram when the forward/reverse switching valve is switched to forward. Fig. 6 is a circuit diagram showing the specific structure of the check valve, switching valve, and differential valve shown in Fig. 4 incorporated therein, and Fig. 7 shows the forward/reverse switching valve shown in Fig. 6 in the forward direction. The circuit diagram corresponding to FIG. 5 after switching, FIGS. 8 to 11 are explanatory diagrams showing the relationship between the operating angle of the control lever and the moving positions of the switching valve and differential valve, and FIG. 12 shows the operation of the control lever. Diagram showing the relationship between position, clutch oil pressure, and slip rate, No. 13
FIG. 14 is an explanatory diagram showing another application example of the differential valve, FIG. 14 is an explanatory diagram of the same valve as a direct-acting type, and FIG. 15 is a hydraulic control circuit diagram showing an advanced application example of the present invention. 1...Oil pan, 2...Strainer, 3...
...Pump, 4...Cooler, 5...Main oil pressure regulating valve, 7...Lubrication oil pressure regulating valve, 8...Accumulator, 10...Forward/forward switching valve, 18...Differential valve, 2
0... Control lever, 22... Switching valve, 24... Check valve, 26... Valve body, 27... Valve, 28...
...Check piston, 33...Valve, 41...Spring seat.

Claims (1)

[Claims] 1. In a reversing speed reducer equipped with a hydraulic friction clutch, a differential valve that operates only when a slip is connected to the oil path leading from the forward/reverse switching valve of the speed reducer to the clutch via a check valve, and the differential valve An oil chamber with a large pressure receiving area and an opposing oil chamber with a small pressure receiving area,
A throttle oil passage that communicates with these oil chambers, a spring that adjusts the differential pressure between the two oil chambers, and an oil passage that communicates with the drain are provided, and the oil passage that communicates with the drain is adjusted with the movement of the differential valve. A control lever is provided to conduct the oil passage to the forward/reverse switching valve through the section and to change the pressing force of the spring, and the control lever is used to switch between normal operation and slip operation. 1. A slip control device for a reversing speed reducer, characterized in that a switching valve as described above is provided and interlocked with the differential valve to control oil pressure before the forward/reverse switching valve.