JPS59190464A - Control device for engine fuel pump - Google Patents

Abstract

PURPOSE:To reduce power consumption upon idling and as well to lower noise, by controlling the discharge amount of a fuel supply pump in accordance with engine operating data such as, for example, a signal from a throttle sensor, an engine rotational speed, an intake-air amount and an intake-air passage pressure. CONSTITUTION:A fuel supply pump 4 is controlled by a relay device 10, and first and second relays are connected to low and high voltage power sources, respectively. A control means 9 reads an intake-air passage pressure Pb and an engine rotational speed (n), an turns on the first realy if Pb<=Pb1 and n<=n1, but turns on the second relay if Pb>Pb1 and n>n1. With this arrangement, power consumption upon idling may be reduced, and noise may be also lowered.

Description

[Detailed description of the invention] The present invention relates to a control device for an engine fuel pump.

There are various types of pumps that supply engine fuel (e.g. gasoline), such as plunger type, roller cell type, and turbine type, but in all conventional fuel pumps, a constant voltage is constantly applied to the pump. Excess fuel not required by the engine is returned to the fuel tank by a fuel pressure regulator.

However, with this conventional method of using an engine fuel pump, there is a problem that most of the fuel discharged from the pump is returned when the fuel flow rate is low, such as when the engine is idling, and power is wasted. . Furthermore, when the fuel flow rate is low, the noise level of the engine and vehicle body is low, so the noise generated by the pump may become a problem.

Considering that the fuel pressure regulator is controlled by the intake passage pressure, the above-mentioned problem becomes particularly noticeable in engines equipped with a turbocharger.

The present invention aims to solve the above-mentioned problems, and provides a control device for a fuel pump for an engine, which controls the fuel pump according to the operating state of the engine to save energy and reduce noise. With the goal.

Therefore, the engine fuel pump control device of the present invention includes a fuel pump installed in the fuel supply system of the engine, and controls the fuel pump according to the operating state of the engine. The engine is characterized by being provided with a detection means for detecting the state, and a control means for receiving a signal from the detection means and outputting a control signal according to the operating state of the engine to the dual fuel pump.

Hereinafter, a control device for an engine fuel pump as an embodiment of the present invention will be explained with reference to the drawings. FIG. 1 is a schematic configuration diagram thereof, and FIGS. 2 and 3 are graphs for explaining its operation. FIG. 4 is a flowchart for explaining the operation.

As shown in FIG. 1, an injector 2 is disposed in the intake passage of the engine 1, and a fuel supply system F that supplies fuel from a fuel tank 5 to the injector 2 includes an electric fuel pump 4. is interposed.

Further, a fuel pressure regulator 3 is provided in the fuel supply line 11 between the fuel pump 4 and the injector 2.
), this fuel pressure regulator 3 controls the amount of fuel returned to the fuel return passage 6 according to the intake passage pressure, and adjusts the natural pressure injected from the injector 2 according to the operating state of the engine 1. It is.

By the way, the discharge pressure-discharge amount characteristic a, the discharge pressure-pump rotation speed (driving frequency) characteristic I] and the discharge pressure-power consumption characteristic C of the fuel pump 4 when a high voltage (for example, 12 volts) is applied are as follows. The result will be as shown in Figure 2. In addition, when the applied voltage is lowered to a low voltage (for example, 6 volts), the discharge pressure-discharge amount characteristic r, the discharge pressure-bump rotation speed (driving frequency) characteristic b', and the discharge pressure-power consumption characteristic C' are respectively The result is as shown in FIG.

Here, when paying attention to the discharge pressure-discharge rate characteristics a and a', the required discharge rate Q is obtained when the fuel flow rate is low, such as during idling. It can be seen that the characteristics d' when a low voltage is applied can be sufficiently simulated.

In addition, by lowering the applied voltage, the pump rotation speed decreases (see the comparison of the characteristics indicated by s and b' in Figure 2), which reduces noise and reduces power consumption (see Figure 2 for comparison). (See the comparison of the characteristics indicated by symbols c and c' in the figure), which shows that energy saving can be achieved.

In view of the above points, the following detection means and control means are provided in order to control the fuel pump 4 according to the operating state.

That is, in addition to the throttle sensor 7 that detects the opening degree of the throttle valve 1a, the engine speed and intake air amount.

A sensor 8 (this sensor 8 consists of a plurality of sensors) that detects various engine operating information such as intake passage pressure is provided, and signals from these sensors 7.8 are input to a computer 9 as a control means. It is now possible to do so.

This computer 9 receives appropriate signals from the sensor 7.8 (particularly the intake passage pressure signal and the engine speed signal) and determines whether the engine is operating in a low output range (this output range is indicated by the symbol d in FIG. 3, for example). If it is in the double low output range, the fuel pump 4 is operated at the above low voltage, and if it is outside the low output range, the fuel pump 4 is operated at the above high voltage. It is possible to output a signal that operates on voltage to the relay device]0.

Here, the relay device 10 has a first and a second relay, and when the fuel pump 4 is operated by applying a high voltage, the first relay is turned off (OFFL) in response to a signal from the computer 9. 2 relay is on (ON) L, when low voltage is applied to the fuel pump 4 and it is operated, the outside is switched in response to a signal from the fuel pump 9, and the 2nd relay is on (ON)
, the second relay is turned off.

Note that the first relay is interposed between the fuel pump 4 and the low voltage source, and the second relay is connected between the fuel pump 4 and the low voltage source. and a high voltage source.

The computer 9 is also capable of receiving signals from the sensors 7 and 8 and outputting a fuel injection signal to the injector 2 in accordance with the engine operating state. Injection control can be achieved.

Note that the symbol C in FIG.
11, [ indicates an equal boost line such that the intake passage pressure pb is a certain value Pb1, and the symbol ID indicates the idle link rotation speed.

Due to the dual configuration, when the engine is in the low output range shown by the symbol J in FIG. Therefore, the fuel pump 4 operates at a low rotational speed with less power consumption and noise, and discharges fuel. The discharge amount characteristic a' at this time is the discharge amount Q required for the double low output region. Since the main conditions can be fully satisfied, there is no problem with fuel pressure control.

In addition, if Ennon 1 is in a state other than the above low output range,
In response to a signal from the computer 9, the first relay of the relay device 10 is turned off and the second relay is turned on, and the fuel pump 4 operates at a high rotation speed, thereby ensuring a sufficient discharge amount.

A series of these processing flows is shown in FIG. 4. That is, first, after reading the intake passage pressure P)) and the engine speed 11, the intake passage pressure pb is set to a certain value P.
I) 1!1j is determined whether it is less than or equal to 1, and if Pl)≦Pb1, it is determined whether the engine speed is 11 or less than a certain value 111.
If ≦n, the first relay is turned on, the second relay is turned off, and the fuel pump 4 is operated at a low number of times.

Also, if pb>pb or n>n, the first
Relay off, second relay on, fuel pump 4
is operated at high rotational speed.

After these processes, the same process as above is performed again.

Note that instead of the relay device 10, the voltage applied to the fuel pump 4 may be continuously controlled using a power transnoster or a cyrisk.

Moreover, as the fuel pump 4, an electromagnetic type can also be used.

As detailed above, according to the engine fuel pump control device of the present invention, the fuel pump is provided in the fuel supply system of the engine, and the fuel pump is controlled according to the operating state of the engine as described in 1. In order to control the fuel pump, there is provided a detection means for detecting the operating state of the ennon, and a control means for outputting a control signal corresponding to the operating state of the engine to the fuel pump in response to a signal from the detection means. It has a simple configuration and has the advantage of contributing to energy saving and noise reduction.

[Brief explanation of the drawing]

The figures show a control device for an engine fuel pump as an embodiment of the present invention.
, 3 are graphs for explaining the operation, and FIG. 4 is a flowchart for explaining the operation. 1... Ennon, 1a... Throttle valve, 2... Injector, 3... Fuel pressure regulator, 4... Fuel pump,
5... Fuel tank, 6... Fuel return passage, 7... Throttle sensor, 8... Sensor, 9... Computer as control means, 10... Relay device, 11... Fuel supply line, F... Fuel supply system. Sub-Agent Patent Attorney Yoshihiko Iinuma Figure 2 Figure 1 Figure 3

Claims (1)

[Claims] The fuel supply system of Ennon is equipped with a fuel pump, and in order to control the fuel pump according to the operating state of the engine, a detection means for detecting the operating state of the engine and a signal from the detection means are provided. 1. A control device for a fuel pump for an engine, comprising: a control means for receiving a control signal and outputting a control signal to the fuel pump according to the operating state of the engine.