JPH0137586B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fuel injection timing adjustment device for use in a diesel internal combustion engine.

Conventionally, there has been an electronic injection timing adjustment system that detects operating conditions such as the rotational speed of the internal combustion engine using various sensors and electronically operates an actuator to obtain the optimal fuel injection timing for the engine. In order to obtain the rotation reference signal of the fuel injection pump, a pickup is installed in the engine part to detect the rotation reference signal, and the fuel injection timing is measured by comparing the rotation signal of the fuel injection pump camshaft with the rotation reference signal as a reference. Was.

However, if engine crankshaft rotation detection and fuel injection pump rotation detection are performed in separate parts like this, the fuel injection pump manufacturer may also use a rotation reference signal detector that is compatible with the rotation reference signal detector installed by the engine manufacturer. Therefore, since fuel injection pump manufacturers also use various rotation signal detectors to match the various rotation reference signal detectors used by each engine manufacturer, many types of rotation signal detectors on the fuel injection pump side are designed. The problem was that it was complicated and the service quality was poor because it had to be prepared and the adjustments were different depending on the type.

Furthermore, in order to extract the rotational signal of the injection pump camshaft, the inside of the injection pump is narrow and there is almost no space to install the pickup, so there is a problem in terms of space, and it is extremely difficult to adjust the pickup.

The present invention aims to solve the above-mentioned problems and provide a fuel injection timing adjustment device that integrates different types of fuel injection timing adjustment devices and has good serviceability. The above object is achieved by incorporating both the signal detection section and the fuel injection pump camshaft rotation signal detector into the fuel injection timing adjustment device for easy adjustment.

The present invention will be explained below with reference to Examples.

1 and 2 relate to embodiments of the present invention, with FIG. 1 being a sectional view along the central axis, and FIG.
This figure is a cross-sectional view showing the state of the pickup at the time of phase adjustment assembly in the - cross section of FIG. 1.

In FIG. 1, a flange 1 is fixed to a fuel injection pump main body 14 with bolts 2, a hydraulic chamber 101 is provided in the flange 1, and a hydraulic piston 11 is freely moved by the action of fluid flowing into the hydraulic chamber 101. can be moved axially. The hydraulic piston 11 is provided with a slope 1101, and a shifter 12 that faces and contacts this slope 1101 and is slidable in the radial direction is disposed, and the shifter 12 is connected to the eccentric shaft pin 12 of the eccentric cam.
01, the small eccentric cam 13 is rotated by the radial movement of the shifter 12, and the driving pin 90 on the drive side fitted to the eccentric cam 16 is
1, the phase of the hub 4 housing the eccentric cam 16 can be changed.

On the other hand, the outer peripheral part 402 of the hub 4 and the cover 10 are rotatably fitted together, and the cover 10 is fixed with bolts 17 to the end cover 9 on which the driving pin 901 is installed. They form one body.

In the above configuration, drive-side uneven portions 1001 are formed at equal intervals on the outer periphery of the cover 10, which is a drive-side rotating member that rotates integrally with the drive shaft of the engine, and is further fixed to the flange 1 with bolts 6. Bracket 5
An electromagnetic drive-side pick-up 7 is screwed onto the bracket 5 and faces the drive-side uneven portion 1001. Furthermore, the bracket 5 has an elongated hole that is movable relative to the flange 1 in the direction of rotation of the cover 10 (in the direction of the arrow shown in FIG. 2).

Further, the fuel injection pump camshaft 15 on the driven side is defined by the drive side uneven portion 1 of the cover 10 on the hub 4 which constitutes the driven side rotating member, which is positioned by the key 18.
Forming the same number of driven side uneven portions 401 as 001,
It is opposed to an electromagnetic driven side pick-up 3 screwed onto the flange 1. Driven side uneven portion 401
has a plane 403 parallel to the axis of the mounting hole of the electromagnetic driven side pickup 3, as shown in FIG.

When the fuel injection timing adjustment device is operated after the adjustment as described above, the electric signal from the drive-side pickup 7 and the electric signal from the driven pickup 3 are input to a computer (not shown), and within the computer, the electric signals from the drive-side pickup 7 and the electric signals from the driven pickup 3 are input to a computer (not shown). The phase angle difference between the two shafts on the driven side is calculated and the fuel injection timing is determined. Then, the hydraulic pressure in the hydraulic chamber 101 is adjusted by adjusting the opening degree of a hydraulic pressure regulating valve (not shown) in accordance with a target value stored in advance in the computer based on engine speed, load, water temperature, etc. Feedback control is performed to adjust the phase of the fuel injection pump camshaft 15 with respect to the drive side so that the fuel injection timing matches the target value.

In the fuel injection timing adjustment device configured as described above, a coupling device (not shown) is attached to the stud bolt 902 of the end cover 9 to the drive shaft of the engine.
By the rotation of the cover 10 attached to the end cover 9 and integrally connected to the end cover 9, electric signals corresponding to the number of the uneven portions 1001 formed on the outer periphery of the cover 10 are generated in the pickup 7. On the other hand, the outer periphery of the hub 4 also has the same number of driven side uneven parts 401 as the driving side uneven parts 1001 formed on the outer periphery of the cover 10.
Similarly, an electric signal is generated in the pickup 3 on the driven side.

Therefore, if the phases of the electrical signals generated by the drive-side pickup 7 and the driven-side pickup 3 are matched in the actuator's most retarded state, the drive-side and driven-side pickups can be matched during operation of the fuel injection timing adjustment device. The fuel injection timing is obtained as an electrical signal from the pickups 7 and 3 as a phase angle shift on both axes.

In order to align the electric signals on the driving side and the driven side in the most retarded state, as shown in FIG. , and fit the parallel plane portion 403 of the hub 4 into the recess at the tip of the positioning pin 19, so that the center of the electromagnetic pickup mounting hole of the flange 1 and the convex portion of the hub 4 are aligned. In this state, next is the protrusion 1001 on the drive side.
The bracket is moved along the direction of rotation through the elongated hole of the bracket 5 so that the protrusion at the tip of the electromagnetic pick-up is aligned with the protrusion at the tip of the electromagnetic pickup, and is fixed with the screw 6 shown in FIG. Finally, the positioning pin 19 is removed and the electromagnetic pickup 3 is assembled to easily complete the positioning.

In this embodiment, the phase angle measurement on the driven side by the electromagnetic pickup 3 on the driven side is performed using the hub 4.
However, as long as it is on the driven side that protrudes from the fuel injection pump main body 14, there is no need to specifically limit the method. You may form a section.

According to the present invention, it is possible to detect the rotation reference signal of the drive shaft and the rotation reference signal of the driven shaft without increasing the size by the drive side pickup and the driven side pickup provided on the fixed member. By adjusting the relative position in the circumferential direction of the drive-side pick-up and the driven-side pick-up on the fixed member, the drive shaft and the driven shaft can be aligned very easily.

Furthermore, the present invention can be applied to any type of diesel internal combustion engine, particularly in the case of a mechanically controlled diesel internal combustion engine using a mechanical fuel injection timing adjustment device using flyweights. This provides an excellent effect in that an electronically controlled diesel internal combustion engine that can be precisely controlled can be obtained simply by replacing the injection timing adjustment device with the fuel injection timing adjustment device of the present invention.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view taken along the central axis of an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along the - cross section of FIG. 1...Flange forming a fixed member, 3...Pickup on the driven side, 4...Hub forming a protrusion on the driven side, 5...Bracket for adjusting relative position.
401... Driven side uneven portion, 7... Drive side pick-up, 10... Cover forming drive side rotating member,
1001...Drive-side uneven portion, 15...Fuel injection pump camshaft.

Claims (1)

[Scope of Claims] 1. The rotation of the drive shaft is transmitted to the driven shaft via an eccentric pair which is inserted between the drive shaft and the driven shaft and consists of a small eccentric disk and a large eccentric disk, and A fuel injection timing adjustment device that operates a piston using hydraulic pressure controlled according to the operating state of the internal combustion engine, and transmits the movement of the piston to the eccentric pair to change the rotational position of the drive shaft and the driven shaft, a fixing member having a hollow portion for accommodating a protrusion of the driven shaft and fixed to the driven side; a fixing member that is rotationally driven integrally with the drive shaft;
a cover that transmits the rotation of the drive shaft to the driven shaft via the eccentric pair; a drive-side uneven portion formed on the outer periphery of the cover; a fixedly provided drive-side pick-up; a number of driven-side uneven portions formed on the outer periphery of the protruding portion of the driven shaft, the same number as the driving-side uneven portions, and facing the driven-side uneven portions; a driven-side pick-up fixedly provided on an inner circumferential portion of the fixed member, the driven-side pick-up and the driving-side pick-up are adjustable in relative positions in the circumferential direction on the fixed member; A fuel injection timing adjustment device that measures and detects fuel injection timing based on a signal generated by a drive-side pickup and a signal generated by a driven-side pickup.