JPS6056252B2 - Fuel injection timing control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control device for fuel injection timing in a fuel injection pump.

Conventionally, in order to improve the operating efficiency of an engine or the exhaust gas components of the engine, a fuel injection pump used in the engine changes its fuel injection timing depending on the rotational speed of the engine.

The method of changing the fuel injection timing in these fuel injection pumps involves detecting the rotational speed of the engine using a centrifugal governor, and using the detected value to change the drive rotation phase angle of the fuel injection pump. The electrically detected engine rotational speed and drive rotational phase angle of the fuel injection pump are independently detected, and the respective detection signals are input to a calculator, and the calculator uses the inputs to It outputs an electric signal corresponding to the drive rotation phase angle that is most suitable for the operating condition of the engine, and the electric signal is converted into hydraulic power, and the hydraulic power operates a hydraulic actuator, which is connected via a link mechanism. In some cases, the drive rotation phase angle of the fuel injection pump is adjusted. Among the conventional methods described above, the former method using a centrifugal governor has non-linear characteristics, making it difficult to increase the response speed in its control.

On the other hand, the latter method has a fundamental property that its control characteristics are excellent since each detection signal has a linear characteristic. However, as mentioned above, these are the engine rotational speed and the drive rotational phase angle that drives the fuel injection pump. In addition, the control based on the detected signal is ultimately controlled with good response, and these configurations can be configured compactly in a narrow engine room. There is a point that must be made. An object of the present invention is to provide a control device that improves the above-mentioned problems in the latter method.

Hereinafter, the present invention will be explained based on Examples.

FIG. 1 shows a front cross-sectional view of an injection timing adjustment device 100 as an embodiment of the present invention.
FIG. 2 shows a system diagram of the entire injection timing control device including the adjusting device 100, and the adjusting device 100 in FIG. 2 is a cross-sectional view of FIG. 1. In Fig. 1, the input shaft 2 enclosing the output shaft 3 is fastened to a side plate 2b by a plurality of bolts 6, and the integrated input shaft 2 and side plate 2b are connected via bearings 1b and 1c. It is pivotally supported on the casing 1 and the side plate 1a, and the side plate 1a is fastened to the casing 1 with bolts (not shown). The output shaft 3 is pivotally supported by a sleeve 2d fitted to the input shaft 2 and a side plate 2b, and a male helical spline 3a cut into the output shaft 3 has a groove twisted with respect to the axial direction of the output shaft 3. The female spline 2g cut into the input shaft 2 is a normal spline parallel to the axial direction of the output shaft 3. A slider 4 is fitted into the annular portion of the male helical spline 3a and the female spline 2g so as to be able to slide in the axial direction, and the male spline 4a and the female helical spline 4b cut into the slider 4 are respectively connected to the female spline 2g. It is configured to fit into the male helical spline 3a.

Here, the male helical spline 3a, the female helical spline 4b1, the slider 4, the male spline 4a, and the female spline 2g constitute a phase angle conversion device. An annular piston portion 4e that is physically fixed to the slider 4
is an annular cylinder 4 constituted by a sleeve 2k fitted to the input shaft 2 and a sleeve 2e fitted to the side plate 2b.
f so that it can slide in the axial direction.

The perforation 2h formed in the input shaft 2 communicates with the end surface 4d of the slider 4, while the perforation 21 formed in the input shaft 2 communicates with the end surface 4c of the piston portion 4e.

The rotary joint 5 is provided with annular grooves 5a and 5b, respectively.
As shown, hydraulic pipes 8a and 8b from hydraulic valve 8
The rotary joint 5 is fixed to the casing 1 in a state where it slides and seals the rotating peripheral surface 2j of the input shaft 2, and the grooves 5a and 5b are connected to the perforations 2h and 21, respectively. It's communicating.

The gear 2a fitted on the input shaft 2 is a part that takes in the rotational power from the engine, and the electromagnetic pickup 9a provided close to the circumference of the gear 2a detects the rotation speed and rotation angle of the input shaft 2. It is detected electrically.

A disc 3b fitted to the output shaft 3 has one or more protrusions 3c cut in the circumferential direction, and 9b is the same electromagnetic pickup as 9a.

9c and 9d are signal lines, 9 is a calculator, 9e is a signal line that sends the output electrical signal of the calculator 9, 6 is a reservoir, 7
is a hydraulic pump, and 7a is a hydraulic pipe.

Further, 1d is an oil seal, 2f is a perforation, and 2c is a gear that drives the hydraulic pump 7. The operation of the configuration shown in FIGS. 1 and 2 above will be explained.

When the input shaft 2 is driven by an engine (not shown), the power is transmitted to the output shaft 3 via the gear 2a1 input shaft 2, the female spline 2g1, the slider male helical spline 3a, and the output shaft 3. It drives a fuel injection pump (not shown) which is coupled to the fuel injection pump.

In this state, since the input shaft 2 is coupled to the engine and driven by a gear, the electromagnetic pickup 9a is connected to the gear 2a.
The fact that the electromagnetic pickup 9a is detecting the rotation speed and rotation angle of the engine means that the electromagnetic pickup 9a is detecting them on the drive shaft of the engine.

On the other hand, the electromagnetic pickup 9b detecting the rotation angle of the output shaft 3 detects the relative rotation phase angle of the output shaft 3 with respect to the rotation angle of the input shaft 2.

These detected values are used as calculation data in the calculator 9 so that the fuel injection pump injects fuel from the most appropriate rotation angle at each engine rotation speed, and the calculation results in the calculator 9 are The output voltage (analog quantity) or the output pulse voltage (digital quantity) operates the hydraulic valve 8 via the signal line 9e, and the hydraulic valve 8 sends a hydraulic quantity corresponding to the output voltage or the output pulse voltage to the hydraulic pipe. Output to 8a or 8b.

Here, the hydraulic valve 8 becomes a proportional control valve when the voltage signal on the signal line 9e is an analog quantity, and becomes an on/off control valve when the voltage signal is a digital quantity.

In the above-described operation, a hydraulic pressure is applied to the hydraulic valve 8a,
When the hydraulic pipe 8b is open to the reservoir 6, the amount of hydraulic pressure acts on the end surface 4d side of the slider 4 via the groove 5a and the perforation 2h, while the pressure oil on the end surface 4c side acts on the perforation 21. ．． It is opened to the reservoir 6 via the groove 5b, the hydraulic pipe 8b and the hydraulic valve 8.

As a result, the slider 4 is pushed to the right by the hydraulic pressure, and at this time, the female spline 2g forms a spline groove parallel to the axial direction of the output shaft 3, while the male helical spline 3a is relative to the axial direction of the output shaft 3,
Since the spline groove is formed with a diagonal twist, when the slider 4 moves to the right, the rotational phase angle of the output shaft 3 increases relative to the input shaft 2.

Since this state in which the relative rotational phase angle increases is constantly monitored by the electromagnetic pickups 9a and 9b,
When the relative rotational phase angle reaches a programmed relative rotational phase angle corresponding to the rotational speed of the engine, the hydraulic valve 8 is closed and as a result the movement of the slider 4 in the axial direction also stops.

Contrary to the above operation, when the relative rotational phase angle of the output shaft 3 with respect to the input shaft 2 is decreased in accordance with the engine rotation speed, the amount of hydraulic pressure is sent to the hydraulic pipe 8b, and the hydraulic pipe 8a is sent to the reservoir 6. When the slider 4 is released and presses the end face 4c side, the slider 4 moves to the left, and the movement corresponds to the relative rotational phase angle programmed in the calculator 9 corresponding to the engine rotation speed. Stopping when this point is reached is the same as the previous explanation.

The fuel injection timing control device according to the present invention operates as described above, but in the above operation, the piston portion 4e is directly integrated with the slider 4 of the phase angle conversion device. , the operation of the piston portion 4e immediately causes the slider 4 to move.

As a result, unlike the conventional structure in which links are provided, there is no room for any movement in the mechanical operation system. Therefore, the control in this operation is
Control with extremely high responsiveness becomes possible.

In the above operation description, in order to change the rotational phase angle, the female spline 2g side may be a helical spline and the male helical spline 3a side may be a normal spline, or both of the above-mentioned splines may be all helical splines. .

Also, by reversing the use of input shaft 2 and output shaft 3, output shaft 3
Even if the input shaft 2 is driven by the engine and the input shaft 2 is used to drive the fuel injection pump, the same effect will result.

As is clear from the above description, the fuel injection timing control device according to the present invention includes a phase angle converter enclosed in the cylindrical input shaft 2, and a phase angle converter in the cylinder. A hydraulic piston portion 4e is installed inside to directly operate the device, and a portion that detects the rotational speed of the engine and its rotational angle necessary for controlling the phase angle conversion device transmits power from the engine. Since gear 2a is used,
There is no need to newly fit the detection disc or the like onto the input shaft 2.

As a result, the axial length of the adjustment device 100 can be shortened, and it has the advantage of being easily installed in the narrow engine room of an automobile, and even if it is made compact. , hydraulic piston part 4e
Since the phase angle converter is directly operated without zero deviations, the control response is improved, which greatly contributes to improving the fuel consumption rate and exhaust gas components of automobiles.

[Brief explanation of the drawing]

FIG. 1 shows a front sectional view of an injection timing adjustment device as an embodiment of the present invention, and FIG. 2 shows a system diagram of the entire control device including the adjustment device. The symbols used in the examples are as follows. 1: Casing, 1a: Side plate, 1b and 1c: Bearing, 1d: Oil seal, 2: Input shaft, 2a: Gear, 2b: Side plate, 2
c: gear, 2d and 2e: sleeve, 2f, 2h and 21: perforation, 2g: female spline, 2j: rotating circumferential surface,
2k: sleeve, 3: output shaft, 3a: male helical spline, 3b: disc, 3c: protrusion, 4: slider, 4a:
Male spline, 4b: female helical spline, 4c and 4d: end face, 4e: piston part, 4f: cylinder,
5: rotary joint, 5a and 5b: groove, 5c:
Pipe, 6: Reservoir, 7: Hydraulic pump, 7a: Hydraulic pipe, 8: Hydraulic valve, 8a and 8b: Hydraulic pipe, 9: Calculator,
9a and 8b: electromagnetic pickup, 9c, 9d and 9e: signal line, 100: adjustment device.

Claims (1)

[Claims] 1. An adjustment device 100 for adjusting the relative rotational phase angle between the input shaft and the output shaft is interposed between the input shaft 2 and the output shaft 3 that drives the fuel injection pump. , the device comprises: (a) cutting the input shaft or the output shaft into a cylindrical shape;
A part of the output shaft or the input shaft is enclosed by screwing the side plate 2b to one end in the axial direction of the tubular shape opened by the cutting, and (b) the enclosed part is A phase angle converter for converting the relative rotational phase angle is provided in a part of the interior in the axial direction, and (c) a hydraulic piston that directly operates the phase angle converter is provided in the enclosed remaining part in the axial direction. The part 4e is installed on the circumference of any gear of the gear train, and is interposed between the input shaft and the engine output shaft. An electromagnetic pickup is fixedly installed on the rotary shaft of the drive system of the output shaft, and a disk 3b having a protrusion 3c on the circumference is fitted, and another electromagnetic pickup is installed on the circumference of the disk. The detection signals of the electromagnetic pickup and the other electromagnetic pickup are used as input signals of a calculator 9, and the calculator drives the hydraulic valve 8 according to the input signal, and the hydraulic valve drives the hydraulic valve 8 according to the input signal. The fuel injection timing is characterized in that the phase angle conversion device is operated by driving a hydraulic piston portion, and the relative rotational phase angle in the adjustment device is adjusted by the operation. control device. 2. The phase angle conversion device has a female spline 2g cut on the input shaft 2, a male spline 3a cut on the output shaft 3, and at least one of the female spline and the male spline has a helical shape. A slider 4 having respective splines that engage with both of the splines is fitted into the annular portion formed by the female spline and the male spline, and the slider 4 is fixed to the piston portion 4e. 2. A fuel injection timing control device according to claim 1, wherein the fuel injection timing control device has a configuration in which: 3. The fuel injection system according to claim 1 or 2, wherein the hydraulic piston portion 4e is configured to fit annularly into a cylinder 4f formed by a cylindrical input shaft 2 and an output shaft 3. Time control device.