JPH0142878B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a constant speed control device for an output shaft of a marine gear for a ship.

In general, when a fishing boat is trolling or when a work boat is stopping at a point on the sea against the force of the current or wind to avoid being carried away by the current or wind, etc., the marine gear position is set to the lowest position. It is required to stably obtain a speed even lower than the idling speed.

For this reason, a constant speed control device for the output shaft of a marine gear for a ship has conventionally been used in which the connection between the engine shaft and the output shaft is controlled at a low speed in a half-clutched state.

As a conventional constant speed control device, there is one shown in FIG. 1, for example.

As shown in the figure, the output of the engine 1 is transmitted to a forward clutch 6 or a reverse clutch 7, and further transmitted to an output shaft 8a and a propeller 8 via a marine gear 10.

Before selectively supplying pressure oil to the hydraulic pump 2 and the forward clutch 6 or reverse clutch,
A low speed valve 4 is connected to the hydraulic path between the reverse switching valve 3 and the reverse switching valve 3.
is installed. On the other hand, the output shaft 8a has
A centrifugal governor 5 is attached.

Now, when performing constant speed control of the output shaft 8a of the marine gear 10, the speed command lever 4 of the constant speed valve 4 is
a to a desired position to set the target rotational speed of the output shaft 8a. Then, low speed valve 4, front
Pressure oil corresponding to the operating position of the lever 4a is selectively supplied to the forward clutch 6 or the reverse clutch 7 via the reverse switching valve 3, and the clutch 6 or 7 to which the pressure oil is selectively supplied becomes a half clutch. Becomes in a clutch state.

On the other hand, in the centrifugal governor 5, the rotational speed of the output shaft 8a is detected, and the operating position of the speed command lever 4a is input, and the rotational speed is set to a low speed so that the deviation between the target rotational speed and the detected rotational speed becomes zero. The valve 4 is adjusted so that the rotational speed of the output shaft 8a becomes the target rotational speed.

In addition, when constant speed control is not performed, the entire discharge pressure oil of the pump 2 is selectively applied to the forward clutch 6 or the reverse clutch 7, bypassing the low speed valve 4, and the clutch 6 or 7 is selectively applied to the forward clutch 6 or reverse clutch 7. directly connected to Therefore, the rotational speed of the output shaft 8a, that is, the propeller 8, can be uniquely determined by the rotational speed of the engine 1 and the gear ratio of the marine gear 10.

However, this type of conventional constant speed control device requires a complicated hydraulic circuit to operate the centrifugal governor, making adjustment difficult, and it is not easy to install on marine gear that does not have a constant speed control device. It was impossible to install it without making significant improvements to the marine gear.

The present invention uses a control circuit with a simple configuration, without using conventional low-speed valves or centrifugal governors, and can be easily installed on marine gear. The oil flow from the hydraulic pump is adjusted by opening/closing control of a solenoid valve according to the deviation between the speed and the set speed to control clutch oil pressure in a half-clutch state, and the solenoid valve is bypassed when the set speed exceeds a predetermined speed. The present invention provides a constant speed control device for a marine gear for ships, which operates a bypass valve to directly connect a clutch regardless of the set speed.

The present invention will be explained in detail below with reference to the accompanying drawings.

FIG. 2 shows an embodiment of the constant speed control device for the output shaft of a marine gear for ships according to the present invention.
The difference from the conventional constant speed control device shown in the figure is that it does not use a centrifugal governor or a low speed valve;
a, that is, a pick-up 22 that detects the rotational speed of the marine gear 10a rotating together with the coaxial shaft 8a.
, a speed setting device 25 that sends out a speed setting signal according to the position of the operating lever 21a, and a pickup 2.
A control circuit 24 that outputs a signal corresponding to the deviation between the output of the speed setter 25 and the output of the speed setting device 25, a normally open solenoid valve 20 that controls opening and closing according to the deviation signal, and a control circuit 24 that outputs a signal corresponding to the deviation between the output of the speed setting device 25 and the output of the speed setting device 25, The solenoid valve 2
This is because a bypass valve 21 that bypasses the

Then, during normal driving, that is, when the stable low speed is not required, the operating lever 21a is operated to open the bypass valve 21, and thereby the hydraulic pump 2 is fully discharged regardless of the control signal from the control circuit 24. Pressure is applied to the forward clutch 6 or reverse clutch 7 bypassing the solenoid valve 20. Therefore, the rotational speed of the output shaft 8a, that is, the propeller 8, can be uniquely determined by the rotational speed of the engine 1 and the gear ratio of the marine gear 10.

Also, when trolling requires a stable speed lower than the idling speed, the bypass valve 21 is closed by operating the lever 21a as shown in FIG. Based on this, the opening and closing are controlled to regulate the discharge pressure from the hydraulic pump 2, and the regulated oil flow is selectively applied to the forward clutch 6 or the reverse clutch 7 via the forward/reverse switching valve 3.

Note that the bypass valve 21 is designed so as to cause almost no oil pressure loss due to passage of oil flow.

FIG. 3 shows details of the control circuit shown in FIG. 2, in which the pickup 22 outputs an electric signal e _p corresponding to the current rotational speed n _p of the output shaft 8a, and the speed setter 25 outputs a predetermined speed N p. _p , and the speed N _p
Outputs the signal Es corresponding to .

Deviation △e obtained by comparing the signals E _s and E _p
(Δe=Es−Ep) is amplified by the amplifier 32 and output to the comparison circuit 34 as the deviation signal _e1 . As shown in FIG. 4a, the triangular wave signal e ₂ output from the triangular wave generating circuit 33 is combined with the deviation signal e ₁ from the comparing circuit 34.
As shown in FIG. 4b, the control signal e 3 is high level for t ₁ hour of e ₂ e ₁ and low level for t ₂ hour of e ₂ < e ₁ , and is sent to the solenoid valve drive circuit ₃₆ .
Output to. Note that here, the low level time
_t2 corresponds to the magnitude of the deviation signal _e1 .

The solenoid valve drive circuit 36 is for switching the position of the solenoid valve 20 according to the level of the control signal _e3 ,
Since the solenoid valve 20 is normally open, it is switched to the open position 20B when the level is low and to the closed position 20A when the level is high.

Therefore, the hydraulic pressure of the solenoid valve 20 is equal to the deviation signal.
Control is performed so that e ₁ becomes 0, that is, the rotational speed of the output shaft 8a becomes the set speed.

Operation position of operation lever 21a and bypass valve 21
To explain the opening/closing relationship of FIG. 5, when the lever 21a is in the range of ∠AOP, that is, the angle α, the bypass valve 21 is closed,
In other words, when the angle is within the range of β, the bypass valve 21
will be opened. However, in this case, as the operating angle gradually increases with OA as a reference, the set speed increases. In this way, in the embodiment, the operation position of the operation lever 21a, that is, the target rotation speed of the output shaft 8a,
Constant speed control is performed so that the deviation from the detection value of the pickup 22, that is, the rotational speed of the output shaft 8a, becomes zero.

As explained above, according to the present invention, since the clutch hydraulic pressure is electrically controlled, speed adjustment becomes easy, installation on marine gear without a constant speed device is extremely easy, and the present invention is simple, inexpensive, and highly reliable. The effects are great, such as being able to configure a constant speed control device.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a conventional constant speed control device for a marine gear for a ship, FIG. 2 is a diagram showing an embodiment of the constant speed control device for a marine gear for a ship according to the present invention, and FIG. 3 is a diagram showing the control shown in FIG. A block diagram showing one embodiment of the circuit, FIGS. 4a and 4b are diagrams showing the generation principle of the output signal of the control circuit in FIG. 3, and FIG. 5 shows the rotation range for each operation of the operating lever in FIG. 2. FIG.

Claims (1)

[Claims] 1. A forward clutch and a reverse clutch that transmit the driving force of the engine to the marine gear in a magnitude corresponding to the hydraulic pressure to rotate the screw, and a hydraulic pump that transmits the hydraulic pressure generated by the hydraulic pump to the forward clutch or the reverse clutch. A forward/reverse switching valve selectively applied to the clutch, a speed detector that detects the rotational speed of the screw, a speed setting device that sets the rotational speed of the screw as a target value according to the operating position, and the hydraulic pump. and a solenoid valve that is installed in the oil passage between the forward and backward switching valve and opens and closes the oil passage; a control circuit for controlling the opening/closing time of the solenoid valve so that the speed setting device is operated to a position beyond a predetermined range; a bypass valve that opens and closes, and when the speed setting device is operated to a position within the predetermined range, the hydraulic pressure regulated by the solenoid valve is applied to the forward clutch via the forward/reverse switching valve. Alternatively, in addition to the reverse clutch, constant speed control of the screw is performed, and when the speed setting device is operated to a position exceeding the predetermined range, the bypass valve is opened and the forward clutch or reverse clutch is directly connected. A constant speed control device for marine gear.