JP3266399B2 - Muffler valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a muffler valve connected to a hydraulic clutch mainly used in a marine reversing machine.

[0002]

2. Description of the Related Art If a constant operating oil pressure is supplied to a hydraulic clutch provided in a marine reducer from a low rotation speed range to a high rotation speed range of an engine, especially when the engine is running at a low speed, a so-called "rattle sound" is generated. Abnormal noise may occur. Conventionally, various measures have been taken to prevent such "rattle noise". For example, by releasing the hydraulic oil on the hydraulic clutch side to a relief circuit through a muffling valve, the pressure on the hydraulic clutch side is reduced. He lowered it and slipped the clutch slightly to eliminate the "rattle".

[0003]

However, when a portion for releasing the high pressure is connected to the inlet of the oil cooler 15 as shown in FIG. 4, the pressure of the oil cooler 15 does not sufficiently decrease due to the resistance of the oil cooler 15, and almost no noise reduction effect is obtained. I couldn't. Also,
As shown in FIG. 5, when the high-pressure release portion is connected to the outlet of the oil cooler 15 in order to reduce the resistance, there is a silencing effect. However, when the engine rotates at a high speed, the flow control valve operates only at a constant flow rate. Because it does not flow, the high-pressure relief valve operates to keep the circuit 2 at high pressure, and the escaped oil is lubricated to each part through the oil cooler and line filter.
Since a certain amount of flow through the flow control valve does not flow through the oil cooler and is lubricated to each part through the line filter,
There was a problem that the oil temperature would rise. In addition, with such a circuit configuration, the high-pressure-side hydraulic pressure at the time of maximum rotation is lower when the muffler valve is operating and when it is not operating, so that there is a problem that the clutch capacity is reduced.

[0004]

The present invention uses the following means to solve the above-mentioned problems. That is, the high-pressure relief valve for setting the normal working oil pressure for the hydraulic clutch and the low-pressure relief valve for setting the initial working oil pressure lower than the normal working oil pressure during low engine rotation were connected in parallel, and the low-pressure relief valve was inserted. The first relief circuit is provided with a flow control valve for keeping the flow rate in the circuit constant, and the oil cooler and the lubricating oil pressure setting in the second relief circuit in which the high-pressure relief valve, the oil cooler, and the line filter are sequentially inserted. The first relief circuit is connected between the pressure regulating valves for use via an on-off valve, and when the amount of oil flowing from the oil cooler reaches a predetermined amount, the connection between the first relief circuit and the second relief circuit is established. Is cut off.

[0005]

By using such means, the hydraulic clutch is engaged to increase the engine speed, and when the amount of oil flowing from the high-pressure relief valve 10 reaches a predetermined amount, the on-off valve 1
4 closes relief oil from the first relief circuit,
The relief oil flows only in the second relief circuit, and is cooled by the oil cooler 15. Conversely, when the number of rotations is reduced, when the amount of oil flowing from the high-pressure relief valve 10 decreases to the set amount of oil, the on-off valve 14 opens to establish a muffler valve circuit.

[0006]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. FIG. 1 is a hydraulic circuit diagram of a marine reversing clutch according to the present invention, FIG. 2 is a cross-sectional view of a muffling valve, and FIG. 3 is a diagram showing a relationship between engine speed and oil pressure.

In FIG. 1, hydraulic oil in a tank 1 is discharged by a hydraulic pump P to a clutch hydraulic oil passage 2, and the hydraulic oil is supplied to a forward / reverse switching valve 4 via a trolling pressure reducing valve 3. When using the trolling, the pressure reducing valve 3
As a result, the pressure in the oil passage 9 is reduced. Since this pressure is lower than the low pressure relief pressure, no oil flows through the first relief circuit. In addition, the governor valve 5 driven by the output shaft of the clutch converts the rotation speed of the output shaft into oil pressure,
To keep the rotation of the output shaft constant. When trolling is not used, the oil passages 2 and 9 are always connected.

The output port of the forward / reverse switching valve 4 is connected to a back pressure oil passage 11 of a high pressure relief valve 10 for setting a normal working oil pressure for a forward clutch 6, a reverse clutch 7 and a hydraulic clutch. Can be supplied to the forward clutch 6 or the reverse clutch 7, and can be supplied to the back pressure oil passage 11 by branching from the clutch operating oil passage 2.

A silencing valve that branches from the secondary oil passage 9 of the trolling pressure reducing valve 3 and sets an initial working oil pressure lower than the normal working oil pressure is a low pressure relief valve 12.
And a flow control valve 13 connected in series to constitute a first relief circuit A. On the other hand, a high pressure relief valve 10, an oil cooler 15, which branches off from the clutch operating oil passage 2.
The line filter 16 is connected in series to form a second relief circuit B. On the secondary side of the line filter 16, a pressure regulating valve 17 for setting a lubricating oil pressure and a lubricating oil passage 19 to each part.
19 ... are connected. The first relief circuit A is connected between the oil cooler 15 of the second relief circuit B and the line filter 16 via the on-off valve 14, and the back pressure of the on-off valve 14 Connected to relief circuit B.

As shown in FIG. 2, the specific structure of the insertion hole 23a for inserting the valve body into the case 23 in the horizontal direction is shown in FIG.
23b and 23c are drilled in parallel from the bottom in order, and the insertion hole 23a and the insertion hole 23b are communication holes 23 drilled in the vertical direction.
d, the insertion hole 23b and the insertion hole 23c are communicated by a communication hole 23e formed in a vertical direction, and the insertion hole 23a is connected to the secondary oil passage 9 of the pressure reducing valve 3 via an oil hole 23g at the deepest portion. And the inlet side of the insertion hole 23c is the inlet 2
4 is provided to communicate with the outlet side of the oil cooler 15, and the inner side of the insertion hole 23c communicates with the vertical hole 23f.
An outlet 25 is provided on the upper outlet side of f and communicates with the inlet side of the line filter 16.

The valve element 12a of the low-pressure relief valve 12 is inserted into the insertion hole 23a, and the valve element 12a is urged by a spring 12b so as to close the gap between the oil hole 23g and the communication hole 23d. The pressure can be adjusted by rotating an adjustment screw 12c screwed on the support member 12d also serving as a lid,
It can be fixed by tightening the nut 12e. 2
3h is a back pressure oil passage.

The flow control valve 13 is inserted into the insertion hole 23b.
Is inserted and closed by the lid 26,
It is urged to the back side by the spring 13b. The spool 1
3a, a through hole 13c is opened at the shaft center, a throttle 13d is fitted into the spring 13b side of the through hole 13c, that is, a secondary side, and the back side of the through hole 13c communicates with the insertion hole 23b to form the spool 1a.
Back pressure is applied to the inner surface of the spool 3a, and the oil passage 13e
13e are opened, and the communication holes 23d
e.

Then, the spool 14a of the on-off valve 14 is inserted into the insertion hole 23c, stopped by the lid 26, and urged toward the lid 26 by the spring 14b.
a, a through hole 14c is opened at the axis, and the aperture 1c is formed on the lid 26 side of the through hole 14c, that is, on the upstream side of the second relief circuit B.
4d so that back pressure is applied to the upstream side of the spool 14a.
open the oil passages 14e, 14e.
The communication can be made from the communication hole 23e to the second relief circuit B.

In such a configuration, as shown in FIG. 3B, the operating hydraulic pressure in the forward clutch 6 is such that the forward / reverse switching valve 4 is switched to the forward side when the rotation speed is a, and the hydraulic pressure is increased. The pressure oil from the pump P is sent to the forward clutch 6 via the pressure reducing valve 3 and the forward / reverse switching valve 4, and is turned on. Since the hydraulic pressure at this time is set to P1 by the adjusting screw 12c of the low-pressure relief valve 12, the forward clutch 6 slips slightly, cutting off the peak of torque fluctuation due to engine rotation fluctuation, and rattling noise. To prevent outbreaks. Also, between the engine rotation speeds a and b, which is the rattle sound generation region, the pump discharge amount increases due to the increase in the engine rotation speed, and the pressure increases slightly due to the override characteristic from P1 to P2. You have set. During this time, the oil leaking from the low-pressure relief valve 12 flows through the total flow rate control valve 13 and the on-off valve 14, and passes through the line filter 16 to the lubricating oil passage 19 without being cooled. Since the clutch generates little heat in the low rotation range between a and b, the oil temperature does not exceed the standard value even if it is not cooled by the oil cooler.

When the engine speed is further increased from b to a high speed region where no rattling noise is generated, the flow control valve 13
And the pressure difference increases before and after the throttle 13d,
Since the spool 13a narrows the communication hole 23d against the spring 13b, the oil pressure in the oil passage 9 starts to increase. When the pressure reaches c , the oil pressure acting on the oil passage 9 and the forward clutch 6 by the high-pressure relief valve 10 becomes P3. The oil leaked from the high-pressure relief valve 10 is cooled by the oil cooler 15, passes through the throttle 14 d of the on-off valve 14, merges with the oil flowing through the flow control valve 13, and is lubricated through the line filter 16. Oilway 1
Flow to 9.

As the engine speed is further increased from the engine speed c, the oil pressure in the oil passage 9 slightly increases due to the increase in the discharge amount of the pump due to the override characteristic of the high-pressure relief valve, and reaches the oil pressure P4 at e. When the flow rate of the throttle 14d of the on-off valve 14 increases, a differential pressure occurs before and after the throttle 14d, and the spool 14a narrows the communication hole 23e against the spring 14b. The first relief circuit and the second relief circuit are shut off. Flow control valve 1
The oil having a constant flow rate flowing through 3 flows into the second relief circuit, and as the flow rate increases, the hydraulic pressure rises from P4 to P5, and the entire amount flows through the oil cooler 15 and is sufficiently cooled. When the rotation is further increased to reach the maximum rotation speed f, the hydraulic pressure reaches P6. Fig. 3-
As shown in (a), when the sound deadening valve is OFF, the oil pressure becomes P6 at the engine speed f, and when the sound deadening valve is ON, the oil pressure becomes P7.
, Which is lower than P6, and at f, which generates the most heat, the entire amount of oil does not flow through the oil cooler 15,
Oil temperature rises.

When the number of revolutions of the engine is reduced, the flow rate flowing through the throttle 14d is increased by a fixed flow rate in (e) of FIG. Opened at d (the flow rate and the oil pressure are approximately proportional), a constant flow rate flows through the first relief circuit, and the flow rate of the high-pressure relief valve decreases accordingly, so that the oil pressure drops.

Further, when the rotation is reduced to c, the flow rate of the flow control valve 13 decreases, the differential pressure before and after the throttle 13d decreases, and the passage of the communication hole 23d increases, and b
In P, the pressure becomes P2 by the low pressure relief valve.
And the hydraulic pressure is such that no rattling sound occurs between a and b.

[0019]

The present invention has the following advantages because it is constructed as described above. That is, the low-pressure relief oil escapes to the oil cooler outlet by the silencing valve so that the noise does not occur until the engine reaches a predetermined rotation from a low rotation to a predetermined rotation. When the engine speed is high, the first relief circuit is blocked, and all the relief oil passes through the oil cooler to prevent the oil temperature from rising. Also, the hydraulic pressure at the maximum rotation becomes equal regardless of the muffler valve ON / OFF, and the clutch capacity does not fluctuate. Furthermore, on-off valve 1
No. 4 does not repeat opening and closing even if the engine speed is maintained at d or e, because the operating engine speeds are different between when the engine speed increases and when the engine speed decreases (because there is hysteresis).

[Brief description of the drawings]

FIG. 1 is a hydraulic circuit diagram of a marine reversing clutch according to the present invention.

FIG. 2 is a sectional view of a muffler valve.

FIG. 3 is a diagram showing a relationship between an engine speed and a hydraulic pressure.

FIG. 4 is a hydraulic circuit diagram of a first comparative example provided with a conventional sound deadening valve.

FIG. 5 is a hydraulic circuit diagram of a second comparative example provided with a conventional sound deadening valve.

[Explanation of symbols]

 A first relief circuit B second relief circuit P hydraulic pump 4 forward / backward switching valve 6 forward clutch 10 high pressure relief valve 12 low pressure relief valve 13 flow control valve 14 on-off valve 15 oil cooler 16 line filter

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) F16D 48/00-48/12 F16D 25/12 F15B 11/028

Claims (1)

(57) [Claims] 1. A low pressure relief valve for connecting a high pressure relief valve for setting a normal working oil pressure to a hydraulic clutch and a low pressure relief valve for setting an initial working oil pressure lower than the normal working oil pressure when the engine is running at a low speed. The first inserted
The relief circuit is provided with a flow control valve for maintaining a constant flow rate in the circuit, the high-pressure relief valve, an oil cooler,
Connecting the first relief circuit via an on-off valve between the oil cooler and the pressure regulating valve for setting the lubricating oil pressure in the second relief circuit in which the line filter is sequentially inserted;
When the amount of oil flowing from the oil cooler reaches a predetermined amount, the connection between the first relief circuit and the second relief circuit is cut off.