JP3639798B2 - Gas engine with electronic governor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a gas engine equipped with an electronic governor, and relates to a technique for simplifying a control system for a throttle valve and a control system for a spark plug.
[0002]
[Prior art]
An example of an electronic governor-equipped gas engine is shown in FIG. FIG. 6 is a schematic diagram of an electronic governor-equipped gas engine, and a symbol E in FIG. 6 indicates the entire gas engine. The gas engine E is configured to optimally control the air-fuel ratio, ignition timing, and the like corresponding to operating conditions while suppressing the generation of pollutant components (CO, HC, NOx) of the exhaust gas. 6, reference numeral 4 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 motor drive circuit for controlling the valve drive motor 29 of the air-fuel ratio control valve 28, 32 is a drive circuit for the governor actuator 25, 33 is an ignition timing of the spark plug 35 via the ignition coil 34. Each igniter to be controlled is shown.
[0003]
In this gas engine E, a throttle valve 22 and an air-fuel mixer 23 are provided in order upstream of the intake manifold 4, an ignition plug 35 is provided facing the combustion chamber 19, and the throttle valve 22 is controlled by a rotational speed control signal R. The governor actuator 25 is configured to be controllable, and the ignition timing of the spark plug 35 is controlled via the ignition coil 34 by an ignition timing control signal S output from the igniter 33.
[0004]
Conventionally, the signal rotor 10 is provided in the interlocking gear 24b that is connected to the crankshaft of the engine, and the ignition timing sensor S4 that opposes the signal rotor 10 and the rotation speed sensor S5 that opposes the interlocking gear 24b are provided separately. The ignition timings of the throttle valve 22 and the spark plug 35 are controlled based on the signals P · N detected by the sensors S4 and S5 arranged in the above. Further, the ignition timing sensor S4 is disposed in a room in which the signal rotor 10 is accommodated.
[0005]
[Problems to be solved by the invention]
In the above prior art, since the ignition timing of the throttle valve 22 and the spark plug 35 is controlled based on the signals detected separately by the sensors S4 and S5, the individual sensors S4 and S5 and the individual sensors are individually controlled. Since the control circuits 32 and 33 are required, the cost increases. Further, the ignition timing sensor S4 is disposed in the accommodation chamber of the signal rotor 10, and the facing position cannot be adjusted from the outside. For this reason, since the ignition timing is adjusted softly by the ignition timing adjustment switch attached to the igniter 33, the cost is increased by the amount necessary for the switch.
[0006]
The present invention has been made in view of such circumstances, and the object thereof is to simplify the individual sensors, simplify the individual control circuits to reduce costs, and oppose the ignition timing sensor S4. The position can be adjusted from the outside, and the ignition timing adjustment switch attached to the igniter is omitted to reduce the cost accordingly.
[0007]
[Means for Solving the Problems]
The present invention has the following basic configuration.
That is, the throttle valve 22 and the air-fuel mixer 23 are provided in order upstream of the intake manifold 4, the ignition plug 35 is provided facing the combustion chamber 19, and the throttle valve 22 is controlled by the engine speed control signal R. The ignition timing of the spark plug 35 is controlled via the ignition coil 34 by the ignition timing control signal S.
[0008]
In order to solve the above-mentioned problem, the invention according to claim 1 is an electronic governor-equipped gas engine having the above-mentioned basic configuration, wherein a detection protrusion is provided on the outer periphery of the signal rotor 10 that is connected to the crankshaft 7, and An ignition timing sensor S4 is provided opposite to the outer periphery of the signal rotor 10, the pickup signal P detected by the ignition timing sensor S4 is waveform-shaped by the waveform shaping circuit 41, and the control signal output circuit is based on the waveform shaping signal Q. 42 is configured to output the rotational speed control signal R and the ignition timing control signal S, and a flange mounting surface is provided outside the outer wall 17 of the housing chamber facing the outer peripheral surface of the signal rotor 10. The flange mounting surface and the mounting flange are seen along the mounting flange 15 and viewed in a direction parallel to the rotation center axis of the signal rotor 10. 5 is formed in a straight line, a long-bolt bolt assembly hole 15a is provided in the turning tangent direction of the signal rotor 10 in the mounting flange 15, the ignition timing sensor S4 is mounted in the mounting flange 15, and the mounting flange 15 is mounted on the flange mounting surface. The ignition timing sensor S4 is provided so that its position can be adjusted along the turning tangential direction of the signal rotor 10 .
[0009]
[0010]
[Operation and effect of the invention]
According to the present invention, the following operations and effects can be achieved. (A) In the invention according to claim 1, in the gas engine equipped with the above-described basic structure, the ignition timing sensor S4 is provided facing the signal rotor 10 linked to the crankshaft 7 and detected by the ignition timing sensor S4. The pickup signal P thus shaped is shaped by the waveform shaping circuit 41, and the rotational speed control signal R and the ignition timing control signal S are output by the control signal output circuit 42 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.
[0011]
(B) In the first aspect of the invention, the ignition timing sensor S4 is provided on the outer wall 17 of the accommodating chamber of the signal rotor 10 so that the position of the signal rotor 10 can be adjusted in the turning tangential direction. Can be adjusted from the outside.
[0012]
(C) In the invention of claim 1 , by adjusting the position of the ignition timing sensor S4 in the turning tangential direction of the signal rotor 10, the relative position between the signal rotor 10 and the ignition timing sensor S4 disposed opposite thereto is determined. The relative distance changes slightly. Thereby, the ignition timing of the spark plug 35 can be finely adjusted. Accordingly, the ignition timing adjusting switch attached to the igniter can be omitted, and the cost can be reduced accordingly.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of an electronic governor-mounted gas engine according to the present invention will be described below with reference to the accompanying drawings. 1 is a schematic diagram 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, and FIG. 3 is a time chart showing a pickup signal, a waveform shaping signal, and an ignition timing control signal for each cylinder. 4A is a front view showing the main part of the gas engine, FIG. 4B is a plan view of a mounting flange of the ignition timing sensor, and FIG. 5 is a left side view of the engine.
[0014]
This electronic governor-equipped gas engine E is a vertical three-cylinder gas engine. As shown in FIGS. 4 and 5, a cylinder block 1 and a crankcase 2 are integrally formed, and a cylinder head 3 is mounted on the cylinder block 1. The intake manifold 4 is fixed to the left side surface of the cylinder head 3, the exhaust manifold 5 is fixed to the right side surface of the cylinder head 3, the oil pan 6 is fixed to the lower surface of the crankcase 2, the cylinder block 1 and the crankcase A gear case 7 is fixed to the front surface of No. 2, front fan drive pulley 8, fan pulley 9 and an alternator pulley (not shown) are interlocked and connected by an endless belt 11, and a flywheel 12 is arranged on the rear surface. 4 and 5, reference numeral 13 denotes a radiator fan, 14 denotes an oil filter, and 16 denotes a cell starter.
[0015]
An intake pipe 20 is erected integrally with the intake manifold 4, and an intake communication pipe 21 including a throttle valve 22 and an air-fuel mixer 23 is connected to the intake pipe 20. An air cleaner 37 communicates with one end 21 a of the intake communication pipe 21 via a communication duct 36. Further, a blowy gas oil separator is connected to one end of the intake communication pipe 21 via a gas reflux pipe 38. A governor actuator 25 is fixed to the rear end portion of the intake manifold 4, and the swing arm 22 a of the throttle valve 22 and the swing arm 25 a of the governor actuator 25 are connected to each other by a connecting rod 24. ing.
[0016]
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 gas fuel, and a branch passage 27 having an air / fuel ratio control valve 28. The valve opening amount of the air-fuel ratio control valve 28 is controlled by a stepping motor 29, and the air-fuel ratio is controlled in accordance with the intake pressure, the oxygen concentration in the exhaust gas, the exhaust temperature, and the like. In FIG. 1, reference numeral 26 a indicates an inlet for the gas fuel G, and 26 b indicates a restriction of the main passage 26.
[0017]
In this embodiment, as shown in FIG. 4 (A), an interlocking gear 24b that rotates at a rotation ratio of 1/2 is connected to a driving gear 24 provided on the crankshaft 7 of the engine via a transmission gear 24a. A signal rotor 10 is provided in the interlocking gear 24b, and an ignition timing sensor S4 is provided opposite to the signal rotor 10. As shown in FIG. 1, a combined control circuit 40 is provided for outputting a rotation speed control signal R for controlling the throttle valve and an ignition timing control signal S based on the pickup signal P detected by the ignition timing sensor S4.
[0018]
The ignition timing sensor S4 is assembled to the housing chamber outer wall 17 of the signal rotor 10 via a mounting flange 15 shown in FIG. This is intended so that the facing position of the ignition timing sensor S4 can be adjusted from the outside. The mounting flange 15 is formed with a long-axis bolt assembly hole 15a in the turning tangent direction of the signal rotor 10, and the ignition timing sensor S4 is assembled so that its position can be adjusted in the turning tangential direction. It is done. This is intended to allow the ignition timing of the ignition plug 35 to be finely adjusted by minutely 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 adjusting switch attached to the igniter can be omitted, and the cost can be reduced accordingly.
[0019]
For example, as shown in FIG. 2, the signal rotor 10 has one wide projection 10a and five other narrow projections 10b, 10c, 10b arranged at equal angular intervals (60 °) in the rotation direction F. -10c and 10b are provided. Since the signal rotor 10 rotates with respect to the crankshaft 7 at a rotation ratio of 1/2, the equiangular interval (60 °) corresponds to a crank angle of 120 °. The pickup signal P shown in FIG. 3 detected by the ignition timing sensor S4 is shaped into the waveform shaping signal Q shown in FIG. 3 by the waveform shaping circuit 41, and the rotational speed is controlled by the control signal output circuit 42 based on the waveform shaping signal Q. The control signal R and the ignition timing control signal S corresponding to the crank angle position of each cylinder are output.
[0020]
That is, the combined control circuit 40 outputs a waveform shaping circuit 41 that outputs a waveform shaping signal Q based on the pickup signal P, and a rotation speed control signal R and an ignition timing control signal S based on the waveform shaping signal Q. And a control signal output circuit 42 for outputting. The control signal output circuit 42 is constituted by a microcomputer, and in addition to the rotational speed control signal R, the ignition coil 34 is energized corresponding to the ignition timing and engine rotational speed corresponding to each cylinder of the multi-cylinder engine. An ignition timing control signal S for controlling time and the like is output.
[0021]
Incidentally, a graph A in FIG. 3 shows an ignition timing control signal for the first cylinder of the gas engine E, a graph B shows an ignition timing control signal for the second cylinder, and a graph C shows an ignition timing control signal for the third cylinder. Indicates. In addition, the symbol a in each graph indicates the energization start timing of the ignition coil 34, and the symbol b indicates the ignition timing of the spark plug 35.
[0022]
With the above configuration, the pickup signal P is detected using the single ignition timing sensor S4, and the rotational speed control signal R and the ignition timing of each cylinder are detected by the combined control circuit 40 including the waveform shaping circuit 41 and the control signal output circuit 42. Since the control signal S is output, the pickup sensor and the control signal output circuit can be simplified to reduce the cost.
[0023]
In addition, this invention is not limited to said embodiment, A various design change is possible in the range which does not change the summary of this invention.
[Brief description of the drawings]
FIG. 1 is a schematic view of an electronic governor-equipped gas engine 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 the ignition timing sensor.
FIG. 5 is a left side view of the gas engine.
FIG. 6 is a schematic diagram of a gas engine equipped with an electronic governor according to a conventional example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 4 ... Intake manifold, 7 ... Crankshaft, 10 ... Signal rotor, 15 ... Ignition timing sensor mounting flange, 17 ... Signal rotor housing outer wall, 19 ... Combustion chamber, 22 ... Throttle valve, 23 ... Air fuel mixer, 25 ... governor actuator, 34 ... ignition coil, 35 ... spark plug, 40 ... combination control circuit, 41 ... waveform shaping circuit, 42 ... control signal output circuit, G ... gas fuel, P ... pickup signal, Q ... waveform shaping signal, R: rotational speed control signal, S: ignition timing control signal, S4: ignition timing sensor.

Claims (1)

A throttle valve (22) and an air / fuel mixer (23) are provided in order upstream of the intake manifold (4), an ignition plug (35) is provided facing the combustion chamber (19), and the throttle valve (22) is provided. It is configured to be controllable via the governor actuator (25) by the rotational speed control signal (R), and the ignition timing of the spark plug (35) is controlled via the ignition coil (34) by the ignition timing control signal (S). In an electronic governor-equipped gas engine configured to
A projection for detection is provided on the outer periphery of the signal rotor (10) connected in transmission with the crankshaft (7), and an ignition timing sensor (S4) is provided on the outer periphery of the signal rotor (10) so as to face the ignition timing sensor. The pickup signal (P) detected in (S4) is waveform-shaped by the waveform shaping circuit (41), and based on the waveform-shaped signal (Q), the control signal output circuit (42) and the rotational speed control signal (R). The ignition timing control signal (S) is output, and a flange mounting surface is provided on the outer side of the outer wall ( 17 ) of the storage chamber facing the outer peripheral surface of the signal rotor ( 10 ) , and a mounting flange is provided on the flange mounting surface. (15) and along a Sig viewed in a direction parallel with the rotational center axis of the signal rotor (10) to form a flange mounting surface and the mounting flange (15) linearly, the mounting flange (15) Rurota (10) turning tangentially provided a long axis of the bolt assembly holes (15a) of the mounting the ignition timing sensor (S4) to the mounting flange (15), a mounting flange (15) along the flange mounting surface moves An electronic governor-equipped gas engine, characterized in that the ignition timing sensor ( S4 ) can be adjusted along the turning tangential direction of the signal rotor ( 10 ) .

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