JPS5840352Y2 - Hydraulic clutch tightening pressure adjustment device - Google Patents

Description

[Detailed description of the invention] The present invention relates to a hydraulic clutch engagement pressure adjustment device in a forward/reverse switching device, etc. installed in a marine engine, and is designed to supply two levels of pressure, high and low, corresponding to the transmission torque of the clutch. be.

By the way, the forward/reverse switching device has an input shaft directly connected to the crankshaft of the engine and an output shaft directly connected to the propeller shaft, and the gear transmission path between the two shafts is switched or interrupted by engaging or disengaging a hydraulic clutch. It is configured to switch between forward, reverse, and neutral states, and in that case, the hydraulic clutch has a pressure regulating valve that adjusts the hydraulic pressure generated by the pump driven by the crankshaft or the input shaft directly connected to the crankshaft to a constant value. It is usually supplied under pressure.

However, in an engine used in a high-speed, high-torque state during running, etc., and a low-speed, low-torque state during operation, such as an engine in a fishing boat, the engagement pressure of the hydraulic clutch can transmit high torque at high speed. However, in this case, at low speeds, the oil pressure becomes excessive compared to the transmitted torque, and as a result, the clutch is suddenly engaged during the switching operation, causing a shock, which damages the propeller shaft joint, etc. In addition to reducing the durability of the engine or causing the engine to stall, the engine's torque fluctuations, which are particularly significant at low speeds, are transmitted directly to the gears, causing problems such as vibration and noise. This was done in consideration of the actual situation, and in the engagement pressure adjustment device installed on the engagement pressure supply path from the pump to the hydraulic clutch, the hydraulic pressure in the supply path is adjusted when the pump discharge amount is less than a certain amount at low speed. A low pressure valve that regulates the pressure to a low pressure value, and a high pressure valve that regulates the hydraulic pressure in the supply path to a high pressure value after the pressure regulating action of the low pressure valve ends when the discharge amount exceeds the above-mentioned certain amount at high speed is provided, As a result, high torque is reliably transmitted at high speeds, and the above-mentioned disadvantages caused by excessive engagement pressure are prevented at low speeds.In addition, by providing a time lag when a high pressure value is supplied as clutch engagement pressure, high oil pressure is achieved. This is intended to alleviate the impact caused by the sudden supply of water.

This will be explained below with reference to the embodiment shown in the drawings. In Fig. 1, 1 is an engine, 2 is a propeller shaft, and 3 is a forward/reverse switching device installed between the two, and although this device is not shown, it is attached to a crankshaft. It has an input shaft that is directly connected to the propeller shaft, and an output shaft that is directly connected to the propeller shaft, and is equipped with a forward gear transmission path and a reverse gear transmission path between the two shafts, and each path is equipped with a hydraulic clutch that connects and disconnects them. ing.

4 is a pump driven by the input shaft; 5 is a switching valve to which hydraulic pressure is supplied from the pump via a fastening pressure supply path 6;
By operating the lever 5a, hydraulic pressure is supplied to one of the hydraulic clutches, or by not being supplied to any of the hydraulic clutches, the vehicle is switched to forward, reverse, or neutral states.

Reference numeral 7 designates a fastening pressure regulating device into which pump discharge oil is introduced from the supply path 6 via a branch path 6a.Next, the configuration of this device will be explained with reference to FIG. 2. 8 is a casing of the device; Two valve holes 9 and 10 are formed, and the front ends of both valve holes are respectively a low pressure port 9a and a high pressure port 10a, and the branch path 6a is further branched and connected. Drain elements L9b and 10 are installed at predetermined positions on the sides of both valve holes.
b are provided respectively.

Reference numeral 11 indicates a low-pressure valve installed in one of the valve holes 9, 12 indicates a low-pressure spring that can push the throttle valve toward the port side, and a through hole is formed in the throttle valve when the low-pressure valve retreats against the spring. 11a
The low pressure port 9a communicates with the drain hole 9b through the drain hole 9a, and the drain hole is configured to close again when the low pressure valve is further retreated.

13 is a high-pressure valve installed in the other valve hole 10, and 14 is a high-pressure spring that presses the throttle valve toward the port side. This spring has a stronger spring force than the low-pressure spring 12, and also resists the spring. By retracting the high pressure valve, the high pressure port NOa is communicated with the drain hole 10b.

15 is a flow path provided between the side of the valve hole 9 in which the low pressure valve 11 is installed and the spring chamber 10c in which the high pressure spring 14 is installed behind the valve in the valve hole 10 in which the high pressure valve 13 is installed. This is a pressure increasing oil passage with a small cross-sectional area, and is configured to communicate with the low pressure port 9a when the low pressure valve 11 moves back and closes the drain hole 9b again.

Reference numeral 16 is a spring receiver for receiving the rear end of the low-pressure spring, and 1T is a spring receiver for receiving the rear end of the high-pressure spring, both of which are screwed into the housing 8 so that they can move forward and backward, and 18 and 19 are both spring receivers. The lock nuts 20 and 21 are cap nuts, and 9' and 10' are air vent holes.

According to the above configuration, the rotational speed of the engine is in the low speed range,
Therefore, when the discharge amount of the pump 4 is less than a certain amount, the engagement pressure regulating device 7 into which the pump discharge oil is introduced from the engagement pressure supply path 6 through the branch path 6a receives the pressure from the low pressure port 9a and operates the low pressure valve. 11 is moved backward against the spring 12, the port 9a communicates with the drain hole 9b through the through hole 11a, and a part of the discharged oil is thereby released, reducing the oil pressure in the supply path 6. That is, the engagement pressure supplied to the clutch is regulated to a low pressure value corresponding to the low pressure spring 12.

In that case, the pump discharge oil is also introduced into the high pressure port NOa, but since the oil pressure is regulated to a low pressure as described above, the high pressure valve 13 is moved back against the spring 14 & the drain hole 10b is opened. It doesn't reach that point.

However, as the rotational speed of the engine increases, the discharge amount of the pump 4 increases, and when this reaches a high speed range exceeding a certain amount, the hydraulic pressure will not be maintained even if the through hole 11a of the low pressure valve 11 opens the drain hole 9b to the maximum. The pressure can no longer be regulated to the low pressure value corresponding to the low pressure spring 12, and the pressure at the port 9a increases, causing the low pressure valve to retreat further and close the drain hole 9b again, resulting in a sudden increase in the oil pressure. At the same time, the low pressure valve is completely retracted, and the high oil pressure acts on the high pressure valve 13 of the high pressure port 10a, and the spring 14
By retreating against this, the high pressure port is now communicated with the drain hole 10b, and as a result, the hydraulic pressure in the engagement pressure supply path 6 supplied to the clutch is transferred to the high pressure spring 14.
The pressure will be regulated to a high pressure value corresponding to .

Furthermore, when the low pressure valve 11 closes the drain hole 9b again, the pressure increasing oil passage 15 communicates with the low pressure port 9a, so hydraulic pressure is introduced into the spring chamber 10c at the rear of the high pressure valve 13, causing the throttle valve to become high pressure. The pressure is applied in the same direction as the spring 14, but since the pressure increasing oil passage has a small flow passage cross-sectional area, oil pressure is gradually introduced, thereby increasing the clutch engagement pressure to a high pressure value corresponding to the spring 14'. After a time lag from the set point, the pressure is increased to a higher predetermined pressure, and the impact that would occur if the tightening pressure is suddenly increased is alleviated. This effect is particularly effective when the engagement pressure adjusting device 7 is installed on the clutch side of the switching valve 5 when switching from neutral to forward or reverse at high speeds.

In addition, in the present invention, since the spring receivers 16 and 17 of the low pressure spring 12 and the high pressure spring 14 are movable, the spring force of both springs can be adjusted to achieve a low pressure value at low speeds and a high pressure value at high speeds. can be set arbitrarily.

As described above, the present invention provides an engagement pressure adjustment device installed on the engagement pressure supply path from the pump to the hydraulic clutch.
A low pressure valve that regulates the oil pressure in the supply path to a low pressure value when the pump discharge amount at low speed is less than a certain amount, and the pressure regulating action of the low pressure valve ends when the pump discharge amount at high speed exceeds the above certain amount. By installing a high-pressure valve that regulates the hydraulic pressure in the supply path to a high pressure value after this, the engagement pressure supplied to the hydraulic clutch is low pressure at low speeds where the transmitted torque is small, and high pressure at high speeds where the transmitted torque is large. As a result, the hydraulic pressure necessary for torque transmission is supplied in any speed range, and by making the hydraulic pressure particularly appropriate at low speeds, it is possible to prevent clutch engagement due to excessive hydraulic pressure at low speeds. This prevents the generation of shocks and the associated adverse effects such as a decrease in the durability of the propeller shaft joint and engine stalling.In addition, clutch slip absorbs the peak torque of engine torque fluctuations that are particularly noticeable at low speeds, reducing vibrations. , noise is reduced, and in particular, in the present invention,
Since a certain time lag occurs when high oil pressure is supplied as clutch engagement pressure, the impact is alleviated, and it has the advantage of being able to arbitrarily set the low pressure value at low speeds and the high pressure value at high speeds. It is.

[Brief explanation of drawings]

FIG. 1 is a hydraulic system diagram of an embodiment of the device of the present invention, and FIG. 2 is an enlarged sectional view showing the internal structure of the embodiment. 4 is a pump, 6 is a fastening pressure supply path, 7 is a fastening pressure adjustment device,
9a, 10a are ports, 9b, 10b are drain holes, 10
c is a spring chamber, 11 is a low pressure valve, 12 is a low pressure spring, 13 is a high pressure valve, 14 is a high pressure spring, 15 is a pressure increasing oil path, 16, 17
is a spring holder.

Claims (1)

[Scope of utility model registration request] A low pressure port and a high pressure port are provided through which pump discharge oil is introduced from the engagement pressure supply path from the pump to the hydraulic clutch.
When the amount of oil introduced into the low pressure port is less than a certain amount, the oil pressure in the supply path is regulated to a low pressure value by retreating against the low pressure spring and opening the drain hole, and the amount of oil introduced is the same amount as above. In the above case, the low-pressure valve further moves back to close the drain hole, and the low-pressure valve closes the drain hole to the high-pressure port, and then moves back against the high-pressure spring to open the drain hole. A high-pressure valve is provided to adjust the hydraulic pressure to a high pressure value, and when the low-pressure valve closes the drain hole, a flow passage with a small cross-sectional area that communicates with the low-pressure port and the spring chamber at the rear of the high-pressure valve is used for pressure increase. A hydraulic clutch engagement pressure adjusting device, characterized in that an oil passage is provided, and the low pressure spring and the high pressure spring are received by a spring receiver that can move forward and backward.