JPS6321807B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hydraulically controlled fuel injection timing adjustment device.

In order to always operate a vehicle tower-mounted internal combustion engine under optimal conditions according to vehicle driving conditions and exhaust gas conditions,
It is necessary to be able to freely control the amount and timing of fuel supply to the engine. Conventionally, control of these two variables has already been implemented for gasoline engines for passenger cars, but it has not yet been implemented for diesel engines. The main reason for this is that the conventional spring-type flyweight timer installed in the fuel injection pump of a diesel engine cannot freely change the fuel supply timing. However, with the development of research over the past few years, a new fuel injection timing adjustment device that can freely change the fuel injection timing has been developed in place of the conventional flyweight timer, so it is now possible to adjust the fuel supply timing even in diesel engines. The prospect of being able to control it freely has been obtained. An example of such a novel fuel injection timing adjustment device is the device disclosed in Japanese Unexamined Patent Application Publication No. 55-5493. These novel fuel injection timing adjustment devices include a first member driven by the engine, a second member that engages with the first member and is connected to the fuel injection pump, and has a gap between the two members. The actuator is equipped with an actuator that generates a rotational phase difference in response to an external control signal. According to this fuel injection timing adjustment device, unlike a conventional flyweight timer, the fuel injection timing can be changed freely, but since a hydraulic actuator is used in this device, it is possible to change the fuel injection timing at will. At the time of starting, the hydraulic actuator does not operate smoothly because the viscosity of the hydraulic oil is high, and there is a risk that the fuel injection timing cannot be accurately controlled.

SUMMARY OF THE INVENTION An object of the present invention is to provide a hydraulically controlled fuel injection timing adjustment device that eliminates the above-mentioned dangers and can ensure smooth operation of the actuator even when the engine is started at low temperatures.

An embodiment of the present invention will be described below with reference to the accompanying drawings.

In FIG. 1, 1 is the main body of a hydraulically controlled fuel injection timing adjustment device. The main body 1 includes a first member 101 coupled to the input shaft 2 and a second member 1 engaged with the first member 101 and coupled to the output shaft 3.
02, and a hydraulic actuator 103 for creating a rotational phase difference between the first member 101 and the second member 102. The input shaft 2 is generally driven by a crankshaft of an internal combustion engine used with the main body 1 via a gear train, while the output shaft 3 is driven by a known fuel injection pump P.
is connected to the camshaft.

The main body 1 may be, for example, the device disclosed in the Japanese Patent Application Laid-open No. 55-5493, but the second
The structure shown in the figure can also be used.

FIG. 2 shows an embodiment of the main body 1. In this embodiment, the first member 101 is a cylindrical portion formed at one end of the input shaft 2, and the first member 101 and the input shaft The shaft 2 is the casing 1 of the main body 1
It is rotatably supported within 04 by bearings 105 and 106. A cylinder 108 is housed inside the first member 101, and a port 101a communicates with an oil groove 108a on the outer peripheral surface of the cylinder 108.
is bored in the wall surface of the first member 101. A rotary oil joint 109 for supplying hydraulic oil to the port 101a is connected to the first member 10.
It is fitted onto the outer peripheral surface of 1. A cylindrical piston 110 that constitutes the hydraulic actuator 103 together with the cylinder 108 and a rotary oil joint 109 is fitted into the cylinder 108, and a female helical is provided on both the inner and outer peripheral surfaces of the other end of the piston 110. A spline 110A and a male helical spline 110B are formed. Among these helical splines, the male helical spline 110B on the outer circumference meshes with the female helical spline 101A formed on the inner circumference of the first member 101, and the female helical spline 110 on the inner circumference
A is engaged with a male helical spline formed on the output shaft 3, that is, the second member 102.
Therefore, in the above configuration, the piston 110
When is moved in the axial direction, the first member 101 and the second member 102 are moved in the rotational direction, and as a result, a rotational phase difference occurs between the input shaft 2 and the output shaft 3 during their rotation, The rotation axis of the fuel injection pump is adjusted to be either phase delayed or phase advanced relative to the crankshaft of the internal combustion engine.

Next, referring again to FIG. 1, the configuration of each part other than the main body 1 will be explained.

A control valve 4 for controlling supply and discharge of hydraulic oil to the hydraulic actuator 103 is provided on the outside of the main body 1, and the control valve 4 is connected to an electric control device 5.
It is configured to be controlled by a control signal from. A hydraulic oil return pipe 6 and a hydraulic oil supply pipe 7 are connected to the control valve 4, and both pipes are connected to a hydraulic oil tank 8.
It is connected to the. A hydraulic pump 9 and a relief valve 10 are provided in the hydraulic oil supply pipe 7 in this order from the upstream side.

A dedicated electric motor 11 is connected to the hydraulic pump 9, and the hydraulic pump 9 is driven separately from the internal combustion engine. The power supply circuit of the electric motor 11 includes a speed control device 12, a pump stop switch 13, a pump start switch 14, and a power source 1.
5 is provided. Pump start switch 1
4 is mechanically interlocked with the starting switch 16 of the internal combustion engine, and is turned on at the same time as the starting switch 16 is turned on. The start switch circuit 17 is provided with a timer 18,
A starting switch 19 operated by the timer 18 is provided in the power supply circuit 21 of the starting motor 20 (of the internal combustion engine). The timer 18 is electrically connected to a time adjustment device 22, and the start time of the operation is adjusted by the time adjustment device 22. An outside temperature detection signal T ₁ and a hydraulic oil temperature detection signal T ₂ are introduced into the time adjustment device 22, and the device 22 changes the operation start time of the timer 18 according to the values of both detection signals. It is composed of

In the hydraulically controlled fuel injection timing adjusting device of the present invention configured as described above, the hydraulic actuator 10
The hydraulic pump 9 for supplying hydraulic oil to the engine 3 is a drive source separate from the internal combustion engine, that is, a dedicated electric motor 11.
Since the hydraulic actuator is driven by the hydraulic actuator, it is possible to operate the hydraulic actuator smoothly even when the viscosity of the hydraulic oil is extremely high, such as when starting at a low temperature, and accurate injection timing adjustment is possible.

Next, the operation of the embodiment will be explained with reference to FIG.

When the start switch 16 is turned on when starting the engine, the pump start switch 14, which is interlocked with the start switch 16, is also turned on immediately and the electric motor 11 is turned on.
is started, and therefore the hydraulic pump 9 is started. As a result, hydraulic oil is circulated through the hydraulic oil supply pipe 7, the control valve 4, the hydraulic actuator 103, and the hydraulic oil return pipe 6.

Since pre-combustion is performed when starting at a low temperature in a cold region, this circuit may be used in place of the starting switch 16. In that case, it is needless to mention in detail that the self-holding circuit must be such that the pump start switch 14 does not turn off at the same time as the pre-combustion circuit is turned off when the pre-combustion is completed. On the other hand, start switch 1
The timer 18 is set with the input of 6, but
The operation start time of the timer 18 is determined by the time adjustment device 22.
For example, if the outside temperature is lower than a predetermined set temperature or the hydraulic oil temperature is lower than a predetermined temperature, timer 1 is
8 is delayed, so starting motor 2
The start switch 19 of 0 is not turned on at the same time as the start switch 16 is turned on, and is kept open for a while. Therefore, the hydraulic oil is sufficiently circulated in the hydraulic circuit of the hydraulic actuator 103 before starting the engine, so that the viscosity of the hydraulic oil decreases and the temperature of the hydraulic oil increases, so that the accurate operation of the hydraulic actuator 103 is prevented. Guaranteed.

When the hydraulic oil temperature rises to a predetermined temperature or at the time set by the time adjustment device 22, the timer 18 is activated by a signal from the time adjustment device 22.
At the same time, the start switch 19 is turned on by the timer 18 and the internal combustion engine is started by the starting motor 20.

After starting the internal combustion engine, the electric motor 11 is controlled by the control device 5 via the speed control device 12 .

As described above, according to the present invention, there is provided a hydraulically controlled fuel injection timing adjustment device that can smoothly operate a hydraulic actuator even when starting at a low temperature.

It should be noted that the control system for the electric motor 11 can be modified in various ways other than the illustrated embodiment, and it is clear that the present invention is not limited to the illustrated embodiment. It goes without saying that the main body 1 may be other than the illustrated embodiment. Furthermore, it is clear that a hydraulic motor, a pneumatic motor, etc. can also be used in place of the electric motor 11.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of an embodiment of the present invention, and FIG. 2 is a longitudinal sectional view of an embodiment of the main body 1. As shown in FIG. 1: Main body, 101: First member, 102: Second member, 103: Hydraulic actuator, 2: Input shaft,
3: Output shaft, P: Fuel injection pump, 4: Control valve,
5: Control device, 6: Hydraulic oil return pipe, 7: Hydraulic oil supply pipe, 8: Hydraulic oil tank, 9: Hydraulic pump, 1
0: Relief valve, 11: Electric motor.

Claims (1)

[Scope of Claims] 1. A first member driven by an internal combustion engine, a second member connected to a fuel injection pump and engaged with the first member, and a first member driven by the internal combustion engine in response to an external control signal. A hydraulically controlled fuel injection timing adjustment device comprising: a hydraulic actuator that creates a rotational phase difference between a member and the second member; a hydraulic pump for supplying hydraulic oil to the hydraulic actuator; A drive source for driving the hydraulic pump separately from the internal combustion engine, a pump start switch for driving the drive source, a start switch for activating a timer in conjunction with the pump start switch, and a start switch for operating the timer. The hydraulic system of the fuel injection timing adjustment device consists of a time adjustment device that gives an operation start time signal, and a start switch for the starting motor of the internal combustion engine, which is turned on by the timer, for a predetermined period of time before starting the internal combustion engine. A hydraulically controlled fuel injection timing adjustment device, characterized in that it operates.