JP2002276522A - Gas engine having electronic governor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce cost by simplifying an individual ignition timing sensor and a rotation speed sensor to one and simplifying individual control circuits to one. SOLUTION: A throttle valve 22 and an air-fuel mixing device 23 are sequentially disposed in an intake manifold 4, an ignition plug 35 is provided facing to a combustion chamber 19, the throttle valve 22 can be controlled by a rotation speed control signal R via a governor actuator 25, and the ignition timing of the ignition plug 35 is controlled by an ignition timing control signal S via an ignition coil 34. An ignition timing sensor S4 is provided facing to a signal rotor 10 transmitted and connected to a crankshaft, a pickup signal P detected by the ignition timing sensor S4 is shaped in waveform by a waveform shaping circuit 41, and the rotation speed control signal R and the ignition timing control signal S are outputted by a control signal output circuit 42 based on a waveform shaping signal Q.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas engine equipped with an electronic governor, and more particularly to a technique for simplifying a throttle valve control system and a spark plug control system.

[0002]

2. Description of the Related Art As a gas engine equipped with an electronic governor,
For example, there is one shown in FIG. FIG. 6 is a schematic diagram of a gas engine equipped with an electronic governor, and reference symbol E in FIG. 6 indicates the entire gas engine. The gas engine E is configured to optimally control the air-fuel ratio, the ignition timing, and the like according to the operating conditions while suppressing the generation of pollutants (CO, HC, NOx) in the exhaust gas. Here, reference numeral 4 in FIG.
Is an intake manifold, 5 is an exhaust manifold, 18 is a three-way catalyst, S1 is a pressure sensor, S2 and S3 are oxygen concentration sensors, S4 is an ignition timing sensor, S5 is a rotation speed sensor,
30 is an air-fuel ratio control circuit, 31 is a drive circuit for controlling a motor for controlling a valve drive motor 29 of the air-fuel ratio control valve 28, 32 is a drive circuit for the governor actuator 25, 33 is a spark plug 3
5 shows an igniter for controlling the ignition timing of No. 5 via the ignition coil 34.

In this gas engine E, a throttle valve 22 and an air-fuel mixer 23 are sequentially provided upstream of the intake manifold 4, a spark plug 35 is provided facing the combustion chamber 19, and the throttle valve 22 is controlled in rotational speed. The system is configured to be controllable by the governor actuator 25 by a signal R, and to control the ignition timing of the ignition plug 35 via an ignition coil 34 by an ignition timing control signal S output by an igniter 33.

Conventionally, a signal rotor 10 is provided on an interlocking gear 24b which is operatively connected to the crankshaft of the engine. The sensors S4 and S5 provided and separately arranged
The throttle valve 2 based on the signal PN detected in
2, and the ignition timing of the spark plug 35 is controlled. Further, the ignition timing sensor S4 is disposed in a room accommodating the signal rotor 10.

[0005]

In the above prior art, the ignition timing of the throttle valve 22 and the ignition plug 35 is controlled based on signals separately detected by the sensors S4 and S5. Since the individual sensors S4 and S5 and the individual control circuits 32 and 33 are required, the cost increases. Further, the ignition timing sensor S4 is a signal rotor 10
And its opposing position cannot be adjusted from the outside. For this reason, since the ignition timing is softly adjusted by the ignition timing adjustment switch attached to the igniter 33, the cost is increased by the amount required by the switch.

The present invention has been made in view of such circumstances, and has as its object to simplify the above-described individual sensors, simplify individual control circuits to reduce costs, and provide an ignition timing sensor. An object of the present invention is to make it possible to externally adjust the opposing position of S4 and to omit the ignition timing adjustment switch attached to the igniter to reduce the cost accordingly.

[0007]

The present invention has the following basic configuration. That is, a throttle valve 22 and an air-fuel mixer 23 are sequentially provided upstream of the intake manifold 4, and a spark plug 35 is provided facing the combustion chamber 19.
Is configured to be controllable via the governor actuator 25 by an engine rotation speed control signal R, and the ignition timing of the ignition plug 35 is controlled via an ignition coil 34 by an ignition timing control signal S.

[0008] In order to solve the above-mentioned problem, the invention according to claim 1 provides an electronic governor-equipped gas engine having the above-mentioned basic structure, wherein an ignition timing sensor S4 is opposed to a signal rotor 10 which is operatively connected to a crankshaft 7. Provided
The pickup signal P detected by the ignition timing sensor S4
Is shaped by the waveform shaping circuit 41, and the waveform shaping signal Q
The control signal output circuit 42 outputs the rotation speed control signal R and the ignition timing control signal S based on the control signal.

According to a second aspect of the present invention, in the gas engine with an electronic governor according to the first aspect, the ignition timing sensor S4 is provided on an outer wall 17 of the housing of the signal rotor 10, and the signal rotor 10 is turned. The position is adjustable in the tangential direction.

[0010]

According to the present invention, the following functions and effects are obtained. (A) In the invention of claim 1, in the gas engine equipped with the electronic governor having the basic configuration, an ignition timing sensor S4 is provided opposite to the signal rotor 10 interlocked with the crankshaft 7, and the ignition timing sensor S4 detects the ignition timing sensor S4. The picked-up signal P is shaped by the waveform shaping circuit 41, and the control signal output circuit 42 outputs the rotation speed control signal R and the ignition timing control signal S based on the waveform shaping signal Q. The rotation speed control signal R and the ignition timing control signal S can be output using the single ignition timing sensor S4, the waveform shaping circuit 41, and the control signal output circuit 42. That is, the cost can be reduced by omitting the conventional rotation speed sensor S5 and the dedicated control circuit 32 that outputs only the rotation speed control signal R.

(B) According to the second aspect of the present invention, in the gas engine with an electronic governor according to the first aspect, the ignition timing sensor S4 is provided on the outer wall 17 of the housing of the signal rotor 10, and the signal rotor 10 is turned. Since the position can be adjusted in the tangential direction, the position facing the ignition timing sensor S4 can be adjusted from the outside.

(C) According to the second aspect of the present invention, the position of the ignition timing sensor S4 is adjusted in the tangential direction of the turning of the signal rotor 10, so that the signal rotor 10 and the ignition timing sensor S4 disposed opposite thereto are adjusted. The relative position and the relative distance slightly change. Thereby, the ignition timing of the ignition plug 35 can be finely adjusted. Accordingly, the ignition timing adjustment switch attached to the igniter can be omitted, and the cost can be reduced accordingly.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a gas engine equipped with an electronic governor according to the present invention will be described below with reference to the accompanying drawings. 1 is a schematic view of a gas engine equipped with an electronic governor according to the present invention, FIG. 2 is a front view of a signal rotor according to the present invention,
FIG. 3 is a time chart showing a pickup signal, a waveform shaping signal, and an ignition timing control signal for each cylinder. FIG. 4A is a front view showing a main part of the gas engine, and FIG. FIG. 5 is a left side view of the engine.

The gas engine E equipped with an electronic governor is a vertical three-cylinder gas engine, as shown in FIGS.
The cylinder block 1 and the crankcase 2 are integrally formed, the cylinder head 3 is fixed on the cylinder block 1, the intake manifold 4 is fixed on the left side of the cylinder head 3, and the exhaust manifold 5 is fixed on the right side of the cylinder head 3. , The oil pan 6 is fixed to the lower surface of the crankcase 2, the gear case 7 is fixed to the front surfaces of the cylinder block 1 and the crankcase 2, and the fan drive pulley 8
, A fan pulley 9 and an alternator pulley (not shown) are operatively connected by an endless belt 11, and a flywheel 12 is arranged on the back surface thereof. 4 and 5, reference numeral 13 denotes a radiator fan, 14 denotes an oil filter, and 16 denotes a cell starter.

An intake pipe 20 is provided in the intake manifold 4.
The intake pipe 20 has a throttle valve 22
And an intake communication pipe 21 having an air-fuel mixer 23. An air cleaner 37 is connected to one end 21 a of the intake communication pipe 21 via a communication duct 36.
A blow-by gas oil separator is connected to one end of the intake communication pipe 21 via a gas recirculation pipe 38. A governor actuator 25 is fixed to the rear end of the intake manifold 4. The swing arm 22 a of the throttle valve 22 and the governor actuator 2
The fifth swing arm 25a is connected with the connecting rod 24 so as to be interlockable.

As shown in FIGS. 1 and 5, the air-fuel mixer 23 communicates with a main passage 26 for supplying LP gas G, which is a gaseous fuel, and a branch passage 27 having an air-fuel ratio control valve 28. The opening amount of the air-fuel ratio control valve 28 is controlled by a stepping motor 29 to control the air-fuel ratio in accordance with the intake pressure, the oxygen concentration in the exhaust gas, the exhaust temperature, and the like. In FIG. 1, reference numeral 26a denotes an inlet for the gas fuel G, and 26b denotes a throttle of the main passage 26.

In this embodiment, as shown in FIG. 4 (A), an interlocking gear 24b rotating at a rotation ratio of 1/2 is connected to a drive gear 24 provided on the crankshaft 7 of the engine via a transmission gear 24a. The signal rotor 10 is provided on the interlocking gear 24b, and an ignition timing sensor S4 is provided to face the signal rotor 10. As shown in FIG. 1, a combined control circuit 40 for outputting a rotation speed control signal R for controlling a throttle valve and an ignition timing control signal S based on the pickup signal P detected by the ignition timing sensor S4 is provided.

The ignition timing sensor S4 is mounted on the outer wall 17 of the housing of the signal rotor 10 via a mounting flange 15 shown in FIG. This is intended to enable the position of the ignition timing sensor S4 to be adjusted externally. In addition, the mounting flange 15 has a bolt mounting hole 1 having a long axis in the tangential direction of rotation of the signal rotor 10.
5a is formed, and the ignition timing sensor S4 is mounted so as to be adjustable in position in the turning tangential direction. This is intended to make it possible to finely adjust the ignition timing of the ignition plug 35 by slightly changing the relative position and relative distance between the signal rotor 10 and the ignition timing sensor S4 disposed opposite thereto. Accordingly, the ignition timing adjustment switch attached to the igniter can be omitted, and the cost can be reduced accordingly.

As shown in FIG. 2, for example, the signal rotor 10 has one wide protrusion 10a and five other narrow protrusions 10b arranged at equal angular intervals (60 °) in the rotation direction F thereof. 10c, 10b, 10c, and 10b. Since the signal rotor 10 rotates at a rotation ratio of 1/2 with respect to the crankshaft 7, the signal rotor 10 has the same angular interval (6
0 °) corresponds to a crank angle of 120 °. Then, the pickup signal P shown in FIG. 3 detected by the ignition timing sensor S4 is converted into a waveform shaping signal Q shown in FIG.
The control signal output circuit 42 outputs a rotational speed control signal R and an ignition timing control signal S corresponding to the crank angle position of each cylinder based on the waveform shaping signal Q.

That is, the combination control circuit 40 outputs a waveform shaping signal Q based on the pickup signal P, a rotational speed control signal R and an ignition timing control signal based on the waveform shaping signal Q. And a control signal output circuit 42 for outputting S. The control signal output circuit 42 is constituted by a microcomputer. In addition to the rotation speed control signal R, the control signal output circuit 42 energizes the ignition coil 34 in accordance with the ignition timing and the engine speed corresponding to each cylinder of the multi-cylinder engine. An ignition timing control signal S for controlling time and the like is output.

Incidentally, graph A in FIG. 3 shows the ignition timing control signal of the first cylinder of the gas engine E, graph B shows the ignition timing control signal of the second cylinder, and graph C shows the ignition timing of the third cylinder. 3 shows a timing control signal. The symbol a in each graph indicates the timing of starting current supply to the ignition coil 34, and the symbol b indicates the ignition timing of the spark plug 35.

With the above configuration, a single ignition timing sensor S
4, a combined control circuit 4 including a waveform shaping circuit 41 and a control signal output circuit 42.
Since 0 outputs the rotation speed control signal R and the ignition timing control signal S for each cylinder, the pickup sensor and control signal output circuit can be simplified to reduce costs.

The present invention is not limited to the above embodiment, and various design changes can be made without departing from the spirit of the present invention.

[Brief description of the drawings]

FIG. 1 is a schematic view of a gas engine equipped with an electronic governor according to the present invention.

FIG. 2 is a front view of a signal rotor according to the present invention.

FIG. 3 is a time chart showing a pickup signal, a waveform shaping signal, and an ignition timing control signal for each cylinder.

FIG. 4 (A) is a front view showing a main part of the gas engine according to the present invention, and FIG. 4 (B) is a plan view of a mounting flange of an ignition timing sensor.

FIG. 5 is a left side view of the gas engine.

FIG. 6 is a schematic view of a gas engine equipped with an electronic governor according to a conventional example.

[Explanation of symbols]

4 ... intake manifold, 7 ... crankshaft, 10 ... signal rotor, 15 ... mounting flange of ignition timing sensor, 17
... outer wall of signal rotor housing, 19 ... combustion chamber, 22 ...
Throttle valve, 23: air-fuel mixer, 25: governor actuator, 34: ignition coil, 35: ignition plug, 40
... combination control circuit, 41 ... waveform shaping circuit, 42 ... control signal output circuit, G ... gas fuel, P ... pickup signal, Q ...
R: rotational speed control signal; S: ignition timing control signal; S4: ignition timing sensor.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F02D 41/04 310 F02D 41/04 310Z 3G301 45/00 362 45/00 362C F02M 21/02 F02M 21/02 L F02P 5/15 F02P 5/15 Z F term (reference) 3G019 AB04 HA01 HA07 3G022 GA01 GA02 GA05 3G065 AA04 CA23 DA04 GA01 GA08 GA10 GA13 HA06 KA02 3G084 AA05 BA05 DA13 EC02 EC07 FA33 FA35 FA38 3G092 CB05 DC09 HC09Z HE01Z HE03Z 3G301 HA22 LA03 LC04 PE01Z PE03Z PE09Z

Claims (2)

[Claims] 1. A throttle valve (22) and an air-fuel mixer (23) are sequentially provided upstream of an intake manifold (4), and a spark plug (35) is provided facing a combustion chamber (19). The valve (22) is configured to be controllable via a governor actuator (25) by a rotation speed control signal (R), and the ignition timing of the ignition plug (35) is controlled by an ignition coil (34) by an ignition timing control signal (S). ), A signal rotor (1) operatively connected to a crankshaft (7).
0), an ignition timing sensor (S4) is provided to face the pickup signal (P) detected by the ignition timing sensor (S4), and the pickup signal (P) is shaped by a waveform shaping circuit (41). A gas engine mounted with an electronic governor, wherein the control signal output circuit (42) outputs the rotation speed control signal (R) and the ignition timing control signal (S) based on the control signal output circuit (42). 2. The gas engine equipped with an electronic governor according to claim 1, wherein the ignition timing sensor is provided on an outer wall of a housing of the signal rotor, and a turning tangent of the signal rotor. An electronic governor-equipped gas engine, characterized in that the position is adjustable in a direction.