JPS6067726A - Controller for controlling jet start time of fuel jet pump of internal combustion engine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is an adjustment device for adjusting the injection start timing of a fuel injection pump of an internal combustion engine, and is an adjustment device for adjusting the injection start timing of a -C1 injection start timing. An adjusting piston is provided which cooperates with a camming mechanism of the plunger of the pump, the adjusting piston comprising:
The pressure medium supplied from the pressure medium storage chamber is loaded with a return force I:i L, and the pressure of the pressure medium is variable in relation to the engine, the pressure control valve has a piston for controlling the opening and opening of the pressure medium storage chamber, the control piston being slidable by the control pressure against the force of a return spring; The entire pressure connection between the pressure side of the piston (29) and the spring chamber receiving the return spring is designed so that the spring chamber is depressurized when a predetermined pressure holding force is exceeded. , in which case an adjustment element is provided for releasing the closed pressure state of the spring chamber.

Conventional technology, for example, Patent Application Publication No. 2648043 of the Federal Republic of Germany
In the adjusting device of this type known from the above specification, the adjusting element is an expanding material element, and the force coil of this expanding material element is connected to the cooling water or the i! ,,',In
It is designed to open and close switches related to τ. If the heating coil is not applied, the constant-pressure valve is opened by the plunger, which causes a pressure to build up on the back side of the piston of the pressure-regulating valve and thus increases the pressure in the pressure medium storage chamber. As a result, the injection start timing is adjusted earlier.When the heating coil is applied, it expands.
The four-year-old diagonal thrust rod controls the opening of the constant pressure valve, thereby reducing the load on the pressure control valve (VC), and the inside of the piston (7) further opens the application opening. control, as a result of which the pressure in the pressure medium storage chamber decreases,
This causes the adjusting piston of the injection start timing adjusting device to again delay the injection start timing to the normal position in the 1-speed operating state.

By carrying out this early temperature-related adjustment during a cold start and when the regulating member is shut off, it is possible to quickly start the internal combustion engine when starting the engine at a cold temperature.

Problems to be Solved by the Invention However, this technique does not allow for early adjustment.

This is because in such cases, it is impossible to completely eliminate large engine noise and so-called non-king.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to improve a regulating device of the type mentioned at the outset in order to solve the problem of high engine noise and knocking at high engine speeds in a simple manner and with high operational reliability.

Means for Solving All Problems In order to solve this problem, in the configuration of the present invention, the adjustment member for releasing the pressure state in which the spring chamber is closed is configured as an electric/mechanical adjustment member. , a switch related to operating temperature and a switch related to engine speed.

The closed state of the spring chamber can be controlled to be released at a predetermined operating temperature or a predetermined engine speed.

Operation The operation of the adjusting device according to the invention will now be explained with reference to the fire pit shown in FIG. Although Vrc in FIG. 1 does not show that the internal combustion engine is already warmed up after starting, since both switches 33 and 31j are closed when starting at room temperature, voltage is applied to the excitation coil 24. Valve (2
5, 26) are closed. Therefore, the fuel flowing out of the spring chamber 28 must open the pressure holding valve 20, and this additional opening pressure leads to the pressure of the fuel A in the pump interior chamber (pressure medium storage chamber) 10. -, and as a result, the adjustment piston 12-: the fuel injection timing is adjusted in the direction of advancing the entire fuel injection timing.

For example, when the temperature of the fuel and the melting speed reach a predetermined value. Both switches 33, 34 and valves (25, 26
) is opened, the pressure in the pump interior 10 drops, and the adjustment is quickly returned.

Embodiments Advantageous embodiments of the invention are described in the dependent claims. In the adjusting device according to claim 3, since the return spring of the tension electromagnet is designed to generate pressure holding force, a separate valve unit is used for this purpose.
7dl-No need to provide. This less expensive adjustment device, however, has the disadvantage that if the tension electromagnet fails,
The disadvantage is that it is not possible to quickly adjust back if necessary based on temperature or rotational speed. This drawback can be eliminated by constructing the device as described in claim 4.

In an internal combustion engine that does not have a rotational speed transmitter (a gear type transmitter, a segment type transmitter, or something similar), the arrangement as described in claim 5 allows the engine rotational speed to be increased. You can easily obtain Nonoramameter.

Is there fuel injection in Figure 1 of the example? In the pump housing 9 of the pump, an injection start timing regulator 11 is shown which acts as a regulator, in which case a regulating piston 12 of the regulator is shown.
is kept in the starting position 14 by a return spring 13. The feed pump 14 has a voltage of 1.0 V inside the pump from the fuel tank 15.
A compartment vane solenoid (not shown) in the pump inner chamber 10 sucks C fuel and generates a fuel slag pressure directly proportional to the pump rotation speed, and the height of this fuel pressure is regulated by the pressure control valve 16. Ru.

When the pump rotation speed exceeds a predetermined rotation speed, the pump inner chamber 1
The pressure at zero overcomes the spring break of the return spring 13 and moves the adjusting piston 12 into a new balance position.1 This movement of the adjusting piston causes a roller ring (not shown) to rotate via the pin 17. This means that the correspondence between the rotating lifting disk and the roller ring changes, and the lifting disk is lifted by the rollers of the roller ring and adjusted earlier. As a result, the injection start time 3 becomes correspondingly earlier.

The normal temperature start acceleration valve I9, which is an adjustment member for canceling the closed state of the spring chamber 28, which will be described later, has a pusher solenoid valve 18 and a pressure holding valve 20 connected in parallel to the valve. ,
A ball 21 loaded by a return spring 23 is in contact with the valve seat 22 of this pressure holding position 2° from the inside. The pressure-electric first valve 18 is configured as a valve closing member 25 and is connected to the valve seat 2.
It has an excitation coil 24 with a complete mover cooperating with the rotor 6. A supply line 27 leads from the spring chamber 28 of the pressure control valve 16 to both valve seats 22,26. The spring chamber 28 is closed by the return spring 30 [and thus the loaded control piston 29 and the anti-piercing surface 31 of the control piston 29].
fully opens and closes the control opening 32, thereby adjusting the predetermined fuel af in the inner chamber 10.

For example, a thermos inch 33 related to the temperature of cooling water or combustion engine 1, and a switch 3 related to the rotation speed of the internal combustion engine.
4 are connected in series to the current path 35 of the exciting coil 24 one after the other. Since the fuel in the internal chamber 10 is directly proportional to the engine speed, the switch 34 related to the engine speed may be a switch that is loaded depending on the fuel pressure.

In the regulating device of FIG. 1, the cold start acceleration valve 19 is shown in the case where the excitation coil 24 is in the rest position and the valves (25, 26) are open. In other words, this indicates a warm and sluggish internal/combustion condition in the high engine speed range.

When starting an internal combustion engine at normal temperature, the temperature-related thermoswitch 33 and the engine speed-related switch 34 are respectively in the closed position, so that the excitation coil 24 to which a voltage is applied is not allowed to perform its work. position and close the valves (25, 26). As a result,
36 throttle holes 1° provided in the instantaneous piston 29
↓Some of the flowing fuel has to open the valves (21, 22) of the pressure holding valve 20 in order to emit tC through the evaporation conduit 37, in which case the additional opening [IE As is well known, as a result of this, the adjustment piston 2 adjusts the injection start timing in the earlier direction as described above.

When a predetermined temperature or a predetermined rotational speed (pressure) reaches or exceeds 1 (I), the thermoswitch 33 and (
or) switch 34 opens the current path, resulting in valve (2
5, 26) are opened and fuel spills out through the outlet conduit 38ff, the closed pressure state of the spring chamber 28 is released, and the adjustment is returned early.

Also in FIG. 2 showing the second embodiment, members that are the same as or similar to those in FIG. 1 are given the same reference numerals. In this embodiment, the cold-start accelerator valve 49 is constructed as a tension solenoid valve, the actuating coil 24 of which is in its working position under the force of the pressure spring 48, and the solenoid valves (25, 26
) Keep it fully open. The force of the pressure spring 48 is adjusted in such a way that when the working position switch valve (25, 26) of the tension electromagnet 44 is opened, a pressure holding force is thereby generated which relieves the pressure in the spring chamber 28.

With this configuration, a separate pressure holding valve is not required. In this second embodiment, unlike the first embodiment, a thermoswitch 33 related to demand and a switch 34 related to rotational speed or pressure are connected in parallel to a current path 35.

FIG. 2 shows a regulating device for a hot internal combustion engine operating in a high speed range, in which case the valves (25,
2C5) is open, and the normal temperature start function is not working. When starting the internal combustion engine at room temperature, both switches 3
3.3'4 opens the current path 35 and the valves (25, 26) are closed by the pressure spring 48. When a predetermined temperature or rotational speed is exceeded, each switch 33,34 closes the current path 35.
is closed, so that the excitation coil 44 assumes the working position shown, whereby the early regulation is restored via the open well (25.degree. 26).

It is also possible to provide the embodiment of FIG. 2 with a pressure holding valve exactly as shown in FIG. In this case, in order to reliably open the pressure holding valve without opening the electromagnetic valve, the closing spring C of the mover and the spring edge of the rE force holding valve must also have a large spring force.

Effects of the Invention The structure of the present invention caused problems in the prior art. Relatively high engine noise and sinking at high rotational speeds can be determined by simple technical measures and with great operational reliability. The invention uses an electro-mechanical regulating element instead of an expandable material element acting as an regulating element, which is controlled not only in relation to the temperature but also in relation to the engine speed. It is based on the idea that the shortcomings of technology can be avoided.

[Brief explanation of drawings]

FIG. 1 schematically shows a first embodiment of an adjusting device according to the invention, and FIG. 2 schematically shows a second embodiment. 9...Pump casing, 10...? The interior of the pump. DESCRIPTION OF SYMBOLS 11... Injection start timing adjustment device, 12... Adjustment piston, 13... Return spring, 14... Feed pump.

Claims (1)

[Scope of Claims] 1. An adjusting device for adjusting the injection start timing of a fuel injection pump of an internal combustion engine, comprising an adjusting piston (12) cooperating with a cam transmission mechanism of a plunger of the injection pump for adjusting the injection start timing. ), the regulating piston is loaded against a return force by a pressure medium supplied from the pressure medium storage chamber (10), so that the pressure of the pressure medium is dependent on the engine parameters. It is variable and controllable by a pressure control valve (6). The pressure control valve has a piston (29) for controlling the outflow opening from the pressure medium storage chamber (10), the control piston being slid by the control pressure against the force of a return spring (30). It is possible that the pressure connection between the pressure side of the control piston (29) and the spring chamber (28,) receiving the return spring (30) is corrugated, the spring chamber (28) having a predetermined When the pressure holding force is exceeded, the pressure is released, and in this case, in the case of a type equipped with an adjusting member for releasing the closed pressure state of the spring chamber (28), 1
The regulating element is designed as an electro-mechanical regulating element (19, 49) and has a switch (3) associated with the operating temperature.
3) and a switch (34) related to the engine speed, the closed state of the spring chamber (28) can be controlled to be released at a predetermined operating temperature or a predetermined engine speed 1"J, -1=. An adjustment device for adjusting the injection start timing of a fuel injection pump of an internal combustion engine. 2. The electric/mechanical adjustment member is a tension solenoid valve (49) or a pressure solenoid valve (19), and Solenoid valve excitation coil (
24)-1 The movable member configured as the valve closing member (25) cooperates with the valve seat (26), and the excitation coil (24) is connected to at least one of the two switches (33, 34). 2. Adjusting device according to claim 1, which is controllable by one side and is such that closing the solenoid valve (19.49) causes the spring chamber (28) to be closed. 3. The tension solenoid valve (49) is adapted to produce a closing sound of the spring chamber (28) in the rest position of its excitation coil, and the pressure spring (48) of the tension solenoid valve (49)
) is adjusted so that in the working position of the tension solenoid valve (49), an external pressure holding force is obtained to release the pressure in the spring chamber (28), and both switches (
3. The regulating device according to claim 2, wherein the current paths (33, 34) are connected in parallel to the current path (35). 4. The pressing solenoid valve (18) is configured to cause the spring chamber (28) to be closed in the working position of the excitation coil (24), and the pressure holding valve (20) that generates pressure holding force is Pressure electromagnet (18) that creates a closed state
are connected in parallel to the excitation coil (2
3. The adjusting device according to claim 2, which is connected one after the other to the current path (35) of 4). 5. The switch related to the engine speed (: (・1) is a switch that is loaded by the pressure of fuel in the pump '+'L (1 (1)) which is a pressure medium storage chamber. Adjustment device according to claim 4. 6. Adjustment device according to claim 4 or 5, in which the pressing solenoid valve (18) and the pressure holding valve (20) are arranged in one common casing (9). Regulator.