JPH0735743U - General-purpose engine starter - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a general-purpose engine starter capable of smoothly starting an engine simply by operating a starter without requiring a preparatory operation before starting the engine. A solenoid drive mechanism 13 capable of urging a choke valve 4c of a carburetor 4 in a closing direction by a coil spring 13c and operating the choke valve 4c in an opening direction against the urging force of the coil spring 13c.
ON to detect the temperature of the engine body 1a
The temperature switch 20 for FF is provided, and the engine body 1a
Temperature switch 2 when the temperature exceeds a specified temperature
When 0 is turned on, the solenoid drive mechanism 13 opens the choke valve 4c.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a starting device for a general-purpose engine used in a brush cutter, a generator, etc., and more particularly to a starting device that does not require a preparatory operation at the time of starting.

[0002]

[Prior art]

 Among the engine starters of this type, the one in which the choke valve of the carburetor is closed in advance and the recoil of the recoil starter is pulled by a rope to start the engine is described in Japanese Utility Model Laid-Open No. 4-91251. There is a device. In this device, a fuel pump that operates by positive and negative pressure when the piston in the general-purpose engine reciprocates when the recoil starter recoils is installed in the fuel tank, and the fuel in the tank is supplied to the carburetor. It is a starting device having a structure.

[0003] Furthermore, when the engine is started, the choke valve of the carburetor is not required to be operated, and the engine is started only by pulling the recoil of the recoil starter with a rope. There is a described device. This device is provided with a fuel passage open to the intake passage between the carburetor and the engine in communication with the fuel tank, and is provided with a fuel valve controlled by a temperature sensor provided in the engine to open and close the fuel passage. This is a starting device that opens the fuel passage when the temperature of the engine is low by the fuel valve, and closes the fuel passage when the temperature rises.

[0004]

[Problems to be solved by the device]

 However, each of the starting devices described in the above publications has room for improvement in the following points.

A. In the former case (Actual Kaihei No. 4-91251): The fuel pump is activated by the positive and negative pressures when the piston moves back and forth during recoil towing, and the fuel in the fuel tank is supplied to the cabletter. There is an advantage that the fuel supply operation to the carburetor by the priming pump, which was required in the past, is not necessary. However, as mentioned above, it is necessary to close the choke valve before starting the engine, and it is necessary to open the choke valve and return it to the original state after the engine starts.

B. In the latter case (Actual Kaihei No. 2-67062): As mentioned above, the intake passage between the carburetor and the engine is connected to the fuel passage from the fuel tank, and when the fuel valve in the fuel passage is opened. Since the fuel passage is only opened to the atmosphere, it is necessary to pull the recoil a considerable number of times before fuel is supplied into the intake passage, which makes starting the engine troublesome. On the other hand, if a fuel supply means such as a priming pump is provided, it is necessary to operate the engine before starting the engine, and when the fuel valve is opened, there is a risk that fuel will leak from the communication port with the atmosphere. is there.

The present invention has been made in view of the above points, and provides a starting device for a general-purpose engine, which can start the engine smoothly by operating the starter without the need for preparatory operation before starting the engine. Is intended.

[0008]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, a starting device for a general-purpose engine of the present invention comprises: a) a fuel pump, which is operated by positive and negative pressure when a piston in the engine body reciprocates, is provided in a fuel tank, In a general-purpose engine starter in which the fuel inside is supplied to the carburetor, b) the choke valve of the carburetor is urged in the closing direction by springing, and the choke valve is urged by the spring to the choke valve. A) A solenoid drive mechanism that can be actuated in the opening direction is connected, and c) A temperature switch that detects the temperature of the engine body and turns it on and off is installed in the engine body, and the temperature of the engine body is set to a predetermined temperature. When the temperature exceeds the above, the temperature switch is turned on and the choke valve is opened by the solenoid drive mechanism. To have.

As described in claim 2, a) a fuel pump that operates by positive and negative pressure when the piston in the engine body reciprocates is provided in the fuel tank, and the fuel in the tank is used as a carburetor. In a general-purpose engine starter configured to supply the fuel, B) a fuel supply path to the carburetor is branched to provide a fuel return path to the fuel tank, and C) a fuel return path is branched to the inside of the carburetor. A second fuel supply passage for supplying fuel to the intake passage between the throttle valve and the engine body is provided, and a solenoid valve for opening and closing the second fuel supply passage is provided in the second fuel supply passage. Installed and urged in the closing direction by a spring, D) A temperature switch that detects the temperature of the engine body and turns it on and off is installed in the engine body. When degree is lower than a predetermined temperature, it may be configured to open the solenoid valves and the temperature switch to ON.

According to a third aspect of the present invention, the general-purpose engine is provided with a recoil starter, and the solenoid drive mechanism or the solenoid valve is generated through an ignition coil when the recoil starter pulls the recoil starter. Anything that operates on electricity can be used.

As described in claim 4, a) a fuel pump that operates by positive and negative pressure when the piston in the engine body reciprocates is provided in the fuel tank, and the fuel in the tank is used as a carburetor. In a starting device for a general-purpose engine that is designed to supply, h) the temperature reaction part of the thermoelement is embedded in the engine body, and i) the operation part of the thermoelement is connected to the choke lever of the carburetor by a link mechanism or the like. The choke valve may be configured to open and close.

Alternatively, as described in claim 5, a) a fuel pump that operates by positive and negative pressure when the piston in the engine body reciprocates is provided in the fuel tank, and the fuel in the tank is supplied to the carburetor. H) A second structure for branching a fuel supply passage to the carburetor to supply fuel to an intake passage between the fuel return passage to the fuel tank and the engine body. A fuel supply path is provided respectively, I) the temperature reaction part of the thermoelement is embedded in the engine body, and J) an opening / closing valve is provided in the middle of the second fuel supply path, and the thermoelement is connected to the opening / closing valve. The operating part may be connected to open and close the on-off valve.

[0013]

[Action]

 According to the starting device of the present invention having the above-mentioned structure (claim 1), since the choke valve is closed before the engine is started, for example, in an engine equipped with a recoil starter, the recoil is performed two or three times by a rope or the like. The engine starts just by towing. That is, when the recoil is rotated, the piston reciprocates, and the positive and negative pulse pressures generated at this time actuate the fuel pump in the fuel tank to supply fuel to the carburetor. In this state, the recoil is further rotated to continue the supply of fuel from the fuel tank to the carburetor, and at the same time the fuel in the carburetor is mixed with air and supplied to the engine body to start the engine. To do. When the engine is started in this way and the warm-up operation is normally performed for about 1 to 2 minutes, the temperature of the engine body rises to a predetermined temperature (for example, 50 ° C) or higher, which is detected by the temperature switch and turned on. Then, the solenoid drive mechanism is energized and the drive mechanism operates to open the choke valve against the spring. Therefore, the air-fuel mixture supplied to the engine is in a normal lean state, and the engine continues to operate. Therefore, when starting the engine, there is no need to supply fuel by the priming pump or open / close the choke valve, and the engine can be started simply by operating the starter.

According to the starting device of the second aspect, the throttle valve in the carburetor is at the idling opening before the engine is started, and the second fuel supply passage is driven by the solenoid valve urged by the spring. It is closed. For example, in an engine equipped with an electric starter, when the engine switch is turned on, the temperature of the engine body is low and is below a predetermined temperature, so the temperature switch is turned on and the solenoid valve resists the biasing force of the spring. It operates in the opening direction and the second fuel supply passage is opened. When the electric starter is operated in this state to rotate the engine, the piston reciprocates to generate positive and negative pressure, and the pulse pressure causes the fuel pump in the fuel tank to operate, causing the fuel to pass through the branch passage and the carburetor to flow. To the fuel supply path to the fuel tank, the fuel return path to the fuel tank, and the second fuel supply path. At this time, since the needle valve of the carburetor is closed, the fuel is supplied to the fuel return passage and the second fuel supply passage, and the inside of the intake passage to the engine body becomes negative pressure, so that the inside of the intake passage is reduced. Fuel is supplied.

When the engine is further rotated by the starter in this state, the fuel supplied into the intake passage is mixed with the air from the carburetor and supplied into the engine body to start the engine. When the engine is started in this way and the warm-up operation is usually performed for about 1 to 2 minutes, the temperature of the engine body rises and becomes higher than a predetermined temperature (for example, 50 ° C), which is detected by the temperature switch. When the solenoid valve is turned off, the solenoid valve moves in the closing direction by the urging force of the spring, and the second fuel supply passage is closed. Also, as the engine speed (speed) increases, negative pressure acts on the carburetor nozzle, the needle valve opens and fuel is supplied into (the metalling chamber of) the carburetor. Therefore, the fuel mixture supplied to the engine becomes a normal lean state, and the engine continues to operate. During this time, pulse pressure from the engine acts on the fuel pump in the fuel tank, and the fuel pump is operating, so fuel is supplied to the carburetor, and part of it returns to the fuel tank through the fuel return path. Therefore, the fuel supply by the priming pump and the opening / closing operation of the choke valve are not necessary at all, and the engine is started simply by operating the starter.

According to a third aspect of the present invention, in the apparatus according to the first aspect, the solenoid drive mechanism operates the choke valve by the electric power generated through the ignition coil when the recoil of the recoil starter is pulled. Although it can be operated in the opening direction, when the engine is started, the temperature of the engine body is usually low, so the temperature switch is OFF and the choke valve is closed by the biasing force of the spring. After the engine has started, if the temperature of the engine rises above a certain temperature after warming up, the temperature switch turns on and current is applied to the solenoid drive mechanism. Open the choke valve against. In the device according to claim 2, the solenoid valve becomes operable in the opening direction by the electric power generated through the ignition coil when the recoil of the recoil starter is pulled, and at this time, the temperature of the engine body is increased. Since the temperature is low, the temperature switch is turned on, so the current is applied to the solenoid valve and the second fuel supply path is opened against the biasing force of the spring. After the engine is started, if the temperature of the engine rises above a certain temperature after warming up, the temperature switch is turned off, so that no current flows to the solenoid valve and the solenoid valve is closed by the biasing force of the spring. And the second fuel supply path is opened.

According to the starting device of the fourth aspect, since the choke valve is closed before the engine is started, for example, in an engine having a recoil starter, when the recoil is rotated, the piston reciprocates. The positive and negative pulse pressures generated at this time actuate the fuel pump in the fuel tank and supply the fuel to the carburetor. In this state, by further rotating the recoil, the fuel supply from the fuel tank to the carburetor is continued, and the fuel in the carburetor is mixed with air and supplied into the engine body to To start. When the engine is started in this way and the warm-up operation is usually performed for about 1 to 2 minutes, the temperature of the engine body rises to a predetermined temperature (for example, 50 ° C) or higher, which causes the temperature response part of the thermoelement to rise. As it heats up, the actuating part of the thermoelement operates and opens the choke valve. Therefore, the air-fuel mixture supplied to the engine is in a normal lean state and the engine continues to operate. Therefore, when starting the engine, there is no need to supply fuel by the priming pump or open / close the choke valve. The engine can be started simply by operating the starter. Thus, the basic operation is almost the same as that of the device of claim 1.

According to the starting device of the fifth aspect, the throttle valve in the carburetor is at the idling opening degree before the engine is started, and the opening / closing valve in the second fuel supply passage is opened. When the engine is rotated in this state, the piston reciprocates to generate positive and negative pressure, and the pulse pressure activates the fuel pump in the fuel tank, and the fuel flows through the branch passage to the fuel supply passage to the carburetor and fuel. It is sent to the fuel return path to the tank and the second fuel supply path. At this time, since the needle valve of the carburetor is closed, the fuel is supplied to the fuel return passage and the second fuel supply passage, and at the same time, the inside of the intake passage to the engine body becomes negative pressure, so that the fuel is not burned in the intake passage. The fee is supplied. When the engine is further rotated in this state, the fuel supplied into the intake passage is mixed with the air from the carburetor and supplied into the engine body to start the engine. When the engine is started in this way and the warm-up operation is normally performed for about 1 to 2 minutes, the temperature of the engine body rises and becomes higher than a predetermined temperature (for example, 50 ° C), which causes the temperature reaction part of the thermoelement to rise. Since the heating is performed, the second fuel supply passage is closed by operating the operating portion of the thermoelement and operating the opening / closing valve in the closing direction. Further, since the engine speed (speed) increases, negative pressure acts on the carburetor nozzle, the needle valve is opened, and fuel is supplied into (the metering chamber of) the carburetor. Therefore, the air-fuel mixture supplied to the engine is in a normal lean state, and the engine continues to operate. During this time, pulse pressure from the engine acts on the fuel pump in the fuel tank, and the fuel pump is operating, so fuel is supplied to the carburetor, and part of it returns to the fuel tank through the fuel return path. Therefore, the fuel supply by the priming pump and the opening / closing operation of the choke valve are not necessary at all, and the engine is started simply by operating the starter. In this way, the basic operation is almost the same as that of the device of claim 2.

[0019]

【Example】

 An embodiment of a starting device for a general-purpose engine according to the present invention will be described below with reference to the drawings. FIG. 1 is a sectional front view showing a general-purpose engine equipped with a starting device according to the present invention and a fuel tank attached to the lower part of the engine, and FIG. 2 is a sectional front view showing an embodiment of the starting device. 3 is a sectional view taken along the line III-III in FIG. 2, and FIG. 4 is an explanatory diagram showing an electric circuit for driving a solenoid.

As shown in FIG. 1, the air-cooled two-cycle general-purpose engine 1 is equipped with a recoil starter 2, and the engine 2 is rotated by pulling a knob 2a at the end of the rope to rotate a recoil (not shown). It is set to start. A carburetor 4 is connected to an intake port of the engine 1 via an insulator 3 made of a heat insulating material, and an air cleaner 5 is connected to an intake port of the carburetor 4.

Although the fuel tank 6 is shown separately in FIG. 1 for the sake of explanation, it is usually integrally attached to the lower surface side of the engine 1. A fuel pump 7 is installed at the bottom bottom position in the fuel tank 6. The fuel pump 7 is a pump driven by positive and negative pressure (pulse pressure) generated by reciprocating movement of a piston 1b (FIG. 2) in the main body 1a of the engine 1, and in this example, the crank chamber of the engine 1 ( Take out the pressure (not shown) to drive. The fuel pump 7 is a well-known diaphragm type pump having a structure in which the diaphragm 7a is operated by a pulse pressure to suck the fuel into the pump chamber 7b and then discharge the fuel from the pump chamber 7b.

A pulse pressure extracting pipe 8 having one end connected to a crank chamber (not shown) of the engine 1 was connected to a pressure chamber 7 c of a fuel pump 7, and one end was connected to a fuel discharge port of the fuel pump 7. The fuel supply pipe 9 is connected to the carburetor 4. The pipe 8 and the fuel supply pipe 9 penetrate a seal member 6a arranged at the center of the upper surface of the fuel tank 6. It is desirable to use a corrugated pipe made of metal for the pipe 8 in order to prevent expansion of the pipe wall due to pulse pressure. A fuel filter 10 is attached to the fuel suction port of the fuel pump 7. A ring-shaped rubber damper 11 is wound around the end of the fuel pump 7 and around the end of the fuel filter 10.

As shown in FIGS. 2 and 3, the carburetor 4 is provided with a choke valve 4c at the air suction port 4a, and the choke valve 4c is rotatably mounted by a rotary shaft 4d. A choke lever 4e is integrally rotatably attached to the rotary shaft 4d, and the choke valve 4c is opened and closed by swinging the choke lever 4e. As shown in FIG. 2, the solenoid drive mechanism 13 is mounted on the upper portion of the air cleaner 5 via the L-shaped bracket 12. In addition to the solenoid coil 13a, the solenoid drive mechanism 13 is provided with a coil spring 13c for urging the T-shaped rod 13b upward (close direction of the choke valve 4c). The lower end of the rod 13b is connected to the end of the choke lever 4e via a pivot support 4f. With this configuration, the choke valve 4c is closed when the solenoid coil 13a is not energized, and when the solenoid coil 13a is energized, the rod 13b is lowered and the choke valve 4c is opened. The solenoid drive mechanism 13 may be mounted on the lower side of the air cleaner 5, and the choke valve 4c may be a solenoid valve.

As shown in FIG. 4, when the recoil (not shown) of the recoil starter 2 (FIG. 1) is pulled by the drive source of the solenoid drive mechanism 13 via the electric circuit 14 and rotated. Use the electric power generated by the AC generator attached to the. That is, a half wave of the AC wave of the ignition coil 15 forming a part of the AC generator is rectified by the diode 16 and the voltage is kept constant by the capacitor 17 before use. Further, in the electric circuit 14, in addition to an igniter 19 for igniting the spark plug 18, a temperature switch 20 for controlling the drive of the solenoid drive mechanism 13 is provided.

The temperature switch 20 has its temperature sensor portion 20a attached in close contact with the engine body 1a (FIG. 2). When the temperature of the engine body 1a rises above a predetermined temperature (for example, 50 ° C.), it is detected. The solenoid coil 13a (FIG. 2) of the solenoid drive mechanism 13 is turned on so as to apply a current. In other words, when the engine body 1a does not reach the predetermined temperature, the temperature switch 20 is in the OFF state, and no current flows to the solenoid coil 13a of the solenoid drive mechanism 13. In this way, the temperature switch 20 is turned on when the temperature of the engine body 1a rises above a predetermined temperature, and a current is passed through the solenoid coil 13a (FIG. 2) to open the choke valve 4c.

The starting device of the embodiment having the above-mentioned configuration functions as follows. That is, in FIGS. 1 to 4, when the recoil is rotated, the piston 1b reciprocates, and the positive and negative pulse pressures generated at this time actuate the fuel pump 7 in the fuel tank 6 and It is supplied to the carburetor 4.

The choke valve 4c of the carburetor 4 is biased by the coil spring 13c of the solenoid drive mechanism 13 to close the intake port. Therefore, by further rotating the recoil in this state, the fuel supply from the fuel tank 6 to the carburetor 4 is continued, and the fuel in the carburetor 4 is mixed with air and supplied into the engine body 1a. Engine 1 starts.

When the engine 1 is started in this way and the warm-up operation is usually performed for about 1 to 2 minutes, the temperature of the engine body 1a rises. At this time, when the temperature exceeds a preset temperature (for example, 50 ° C.), it is detected by the temperature sensor portion of the temperature switch 20 and turned on, so that a current is applied to the solenoid coil 13a of the solenoid drive mechanism 13 and the choke valve 4c is turned on by the coil spring. Open against 13c. Then, the air-fuel mixture supplied to the inside of the engine body 1a becomes a normal lean state, and the operation of the engine 1 is continued. Therefore, the user can start the engine 1 by pulling the recoil starter 2 several times.

Next, FIG. 5 is a partially sectional front view showing a general-purpose engine equipped with a starting device according to another invention and a fuel tank attached to the lower part thereof, and FIG. 6 is a starting view of FIG. It is a front view sectional view showing an example of a device.

The main difference between the starting device of the present invention and the first device described above is that the carburetor 4 ′ does not include a choke valve 4 c (FIG. 2), and instead, when the engine body 1 a is cold. That is, a mechanism for supplying a part of the fuel is provided in the intake passage between the carburetor 4'and the engine body 1a. More specifically, as shown in FIG. 5, a fuel pump 7 driven by positive and negative pressure when the piston 1b (FIG. 6) of the engine 1 reciprocates is provided in the fuel tank 6. The fuel supply pipe 9 is branched, one of which is a fuel supply pipe 21 to the carburetor 4 ′ and the other of which is a fuel return pipe 22 to the fuel tank 6. The fuel return pipe 22 is further branched from the middle, and in this example, is configured as a second fuel supply pipe 23 communicating with the inside of the insulator 3 as shown in FIG.

As shown in FIG. 6, a throttle portion 22 a is formed at the inlet of the fuel return pipe 22. A solenoid valve 25, which is a starting fuel valve, is provided in the second fuel supply pipe 23 that branches downward immediately downstream of the throttle portion 22a. It is urged in a direction to close the passage in the supply pipe 23. The drive source of the solenoid valve 25 uses the electric power generated when the recoil starter 2 pulls the recoil, and has a similar electrical circuit (see FIG. 4) in common with the previous invention. The 20 ON / OFF operations are completely reversed. That is, the temperature switch 20 is in the ON state until the temperature of the engine body 1a reaches a predetermined temperature (for example, 60 ° C.), but when the temperature exceeds the predetermined temperature, the temperature switch 20 is turned off and turned off. Then, when the temperature of the engine body 1a is low and the temperature switch 20 is ON, the solenoid valve 25 operates to open the passage in the fuel supply pipe 23.

The second fuel supply pipe 23 can be connected to the insulator 3 as well as to the intake port portion of the engine body 1a or the throttle valve 4f downstream side of the carburetor 4 as shown by the chain double-dashed line. Reference numeral 20a in FIG. 6 denotes a temperature sensor portion of the temperature switch 20 (FIG. 4), which is attached in close contact with the engine body 1a. In addition, 4g is a metering chamber and 4h is a needle valve. Since other configurations are common to the previous invention, common members are denoted by the same reference numerals.

The starting device of the present example having the above-described configuration functions as follows. That is, in FIG. 5 and FIG. 6, before the engine 1 is started, the throttle valve 4f in the carburetor 4 ′ is at the idling opening, and the passage in the second fuel supply pipe 23 is the spring 26. It is closed by an energized solenoid valve 25.

The electric circuit 14 (FIG. 4) works with the electric power generated when the recoil of the recoil starter 2 is pulled and rotated. Then, since the temperature of the engine body 1a is low and equal to or lower than the predetermined temperature, the temperature switch 20 (FIG. 4) is in the ON state, the solenoid valve 25 operates in the opening direction, and the inside of the second fuel supply pipe 23 Open the passage. Further, the positive and negative pulse pressures generated when the piston 1b reciprocates actuates the fuel pump 7 in the fuel tank 6 to feed the fuel from the fuel supply pipe 9. At this time, since the needle valve 4h of the carburetor 4'is closed, the fuel is supplied to the fuel return passage 22 and the second fuel supply passage 23, and the inside of the insulator 3 becomes a negative pressure. Fuel is delivered to.

By further pulling the recoil of the recoil starter 2 in this state, the fuel in the insulator 3 is mixed with the air from the carburetor 4'and supplied into the engine main body 1a to start the engine.

When the engine 1 is started in this way and the warm-up operation is normally performed for about 1 to 2 minutes, the temperature of the engine body 1a rises, and when the temperature becomes higher than a predetermined temperature, this is the temperature of the temperature switch 20. It is detected by the sensor portion 20a and turned off, the solenoid valve 25 moves in the closing direction by the urging force of the spring 26, and the passage in the second fuel supply pipe 23 is closed. Also, during the warm-up operation, the fuel pump 7 operates, the fuel supply amount from the fuel tank 6 increases, and the rotation speed (speed) of the engine 1 also increases, so that negative pressure acts in the cab letter 4 '. The needle valve 4h is opened and fuel is supplied into the metering chamber 4g. As a result, the air-fuel mixture supplied into the engine body 1a is in a normal lean state, and the operation of the engine 1 is continued.

The fuel flow rate when the solenoid valve 25 is open is set so that the engine 1 can be operated for about 1 to 2 minutes with the fuel from the second fuel supply pipe 23 to the insulator 3.

FIG. 7 is a front sectional view showing an embodiment of a starting device according to another invention. The starting device of this example is basically the same as the starting device of FIG. 2, and the main difference from this is that the thermoelement 30 is used instead of the solenoid drive mechanism 13 (FIG. 2). . As shown in FIG. 7, the thermo element 30 is semi-fluid through the diaphragm 33 when the wax 32 filled in the wax case 31 at the base end serving as the temperature reaction part is heated and expanded. The retainer 38, which is transmitted to the body 34, the rubber piston 35, the plate 36, and the piston 37 and acts as an operating portion, projects forwards against the return spring 39. The thermoelement 30 is mounted by embedding a wax case 31 at the base end in the engine body 1a. The operation (displacement) characteristics of the retainer 38 of the thermoelement 30 can be set arbitrarily.

One end of a link lever 40 is connected to the upper end of the choke lever 4 e of the carburetor 4 by a connecting tool 41. The link lever 40 is pivotally supported by a pivot support 42 at a substantially central portion, and the other end of the link lever 40 is pivotally supported by a support shaft 44 on an upper end of a retainer 38 of the thermoelement 30. With this configuration, when the temperature of the engine body 1a becomes high and the wax case 31 is heated, the retainer 38 projects upward and the linking tool 41 side of the link lever 40 is lowered, so that the choke valve 4c is opened. On the other hand, when the temperature of the engine body 1a is low (when the engine 1 is started), the retainer 38 is urged to the retracted position by the return spring 39, so that the choke valve 4c is closed as shown in FIG. . Since other configurations are common to those of the starting device of FIG. 2, common members are illustrated with the same reference numerals as those of FIG. 2, and description thereof is omitted. A rod or push-pull cable may be used instead of the link mechanism such as the link lever 40.

Next, FIG. 8 is a front sectional view showing an embodiment of a starting device according to another invention. The starting device of this example is basically the same as the starting device of FIG. 6, and the main difference is that the temperature switch 20 and the solenoid valve 25 (FIG. 6) are replaced by the same structure as that of FIG. That is, the thermoelement 30 is used. This thermoelement 30 is mounted by embedding a wax case 31 at the base end in the engine body 1a, as in the starting device of FIG. Further, the fuel supply pipe 9 is branched to a second fuel supply pipe 43 communicating with the inside of the insulator 3 before the branching portion between the fuel supply pipe 21 to the carburetor 4 ′ and the fuel return pipe 22 to the fuel tank 6. ing. An opening / closing valve 45, which is a starting fuel valve, is provided in the second fuel supply pipe 43, and the retainer 38 of the thermoelement 30 is directly connected to the opening / closing valve 45. When the temperature of the engine body 1a is low (when the engine 1 is started), the retainer 38 is urged to the retracted position by the return spring 39, so that the opening / closing valve 43 is opened as shown in FIG. . On the other hand, when the engine 1 is warmed up for about 1 to 2 minutes after starting, the temperature of the engine body 1a rises and becomes higher than the predetermined temperature, so the wax case 31 is heated and the retainer 38 is moved forward. The opening / closing valve 45 closes the passage of the second fuel supply pipe 43. Since other configurations are common to those of the starting device of FIG. 6, common members are illustrated with the same reference numerals as those in FIG. 2, and description thereof is omitted.

By the way, the above-described general-purpose engine is a system that is started by the recoil starter 2, but it can be similarly implemented when it is started by an electric starter. The starting device of the present proposal can also be applied to a water-cooled 4-cycle engine.

[0042]

[Effect of device]

 As is clear from the above description, the general-purpose engine starter of the present invention has the following effects.

(1) The fuel supply by the priming pump and the closing operation of the choke valve before starting are completely unnecessary, and the engine is started only by operating the starter. When the warm-up operation is completed after the engine is started, the choke valve is automatically opened and the normal operating condition is restored.

(2) In the device according to claim 2, the carburetor does not have a choke valve, and therefore the choke valve does not need to be opened / closed at all, and the fuel supply by the priming pump is also unnecessary. As with the starter in paragraph 1, the engine is started simply by operating the starter. After the warm-up operation is completed, the fuel supply to the inside of the insulator is automatically stopped and the normal operation state is restored.

(3) In the device according to the third aspect, since the solenoid and the electric circuit work with the electric power generated when the recoil starter pulls the recoil, a dedicated power source such as a battery is not required.

(4) The device according to claim 4 has the same effect as the device according to claim 1, and the opening / closing operation of the choke valve is automatically performed by the thermoelement based on the temperature change of the engine body. Therefore, there is an effect that the structure is further simplified.

(5) The device according to claim 5 has the same effect as that of the device according to claim 2, and the opening / closing operation of the choke valve is automatically performed by the thermoelement based on the temperature change of the engine body. Therefore, there is an effect that the structure is further simplified.

[Brief description of drawings]

FIG. 1 is a partially sectional front view showing a general-purpose engine equipped with a starting device of the present invention and a fuel tank attached to the lower part thereof.

FIG. 2 is a front sectional view showing an embodiment of a starting device of the present invention.

3 is a sectional view taken along line III-III in FIG.

FIG. 4 is an explanatory diagram showing an electric circuit for driving a solenoid.

FIG. 5 is a partially sectional front view showing a general-purpose engine equipped with a starting device according to a second aspect of the present invention and a fuel tank attached to the lower portion thereof.

FIG. 6 is a front sectional view showing an embodiment of the starting device of FIG.

FIG. 7 is a front sectional view showing an embodiment of a starting device according to a third invention of the present invention.

FIG. 8 is a front sectional view showing an embodiment of a starting device according to a fourth invention of the present invention.

[Explanation of symbols]

 1 General-purpose engine 1a Engine body 2 Recoil starter 3 Insulator 4/4 'Carburetor 5 Air cleaner 6 Fuel tank 7 Fuel pump 13 Solenoid drive mechanism 15 Ignition coil 16 Diode 17 Capacitor 18 Spark plug 19 Igniter 20 Temperature switch 23.43 Second fuel supply Pipe 25 Solenoid valve 30 Thermoelement 45 Open / close valve

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display area F02N 17/08 E

Claims (5)

[Scope of utility model registration request] 1. A starting device for a general-purpose engine, wherein a fuel pump that operates by positive and negative pressure when a piston in an engine body reciprocates is provided in a fuel tank, and the fuel in the tank is supplied to a carburetor. , A carburetor choke valve is biased by a spring in a closing direction, and a solenoid drive mechanism that is operable in an opening direction against the biasing force of the spring is connected to the choke valve, A temperature switch for detecting ON / OFF is provided in the engine body, and when the temperature of the engine body exceeds a predetermined temperature, the temperature switch is turned ON and the choke valve is opened by the solenoid drive mechanism. A starting device for a general-purpose engine having the above structure. 2. A starting device for a general-purpose engine, wherein a fuel pump that operates by positive and negative pressure when a piston in an engine body reciprocates is provided in a fuel tank, and the fuel in the tank is supplied to a carburetor. A fuel supply path to the carburetor is branched to provide a fuel return path to the fuel tank, and the fuel return path is branched to supply fuel to an intake passage between the throttle valve in the carburetor and the engine body. To provide a second fuel supply passage for
A solenoid valve for opening and closing the second fuel supply passage is provided in the second fuel supply passage and is urged in a closing direction by a spring, and a temperature switch for detecting the temperature of the engine body and turning it on and off is provided to the engine. When the temperature of the engine body is below a predetermined temperature, the temperature switch is turned on when the temperature switch is installed in the body.
A general-purpose engine starter characterized in that the solenoid valve is set to N to open the solenoid valve. 3. The engine includes a recoil starter, and the solenoid drive mechanism or the solenoid valve,
The starting device for a general-purpose engine according to claim 1 or 2, wherein the recoil starter is operated by electric power generated via an ignition coil when the recoil starter pulls the recoil. 4. A starting device for a general-purpose engine, wherein a fuel pump that operates by positive and negative pressure when a piston in an engine body reciprocates is provided in a fuel tank, and the fuel in the tank is supplied to a carburetor. A starting device for a general-purpose engine, wherein a temperature reaction part of a thermoelement is embedded in the engine body, and a choke lever of the carburetor is connected to an operating part of the thermoelement by a link mechanism or the like to open and close the choke valve. 5. A starting device for a general-purpose engine, wherein a fuel pump that operates by positive and negative pressure when a piston in an engine body reciprocates is provided in a fuel tank, and the fuel in the tank is supplied to a carburetor. A fuel return path for branching the fuel supply path to the carburetor and a second fuel supply path for supplying fuel to an intake path between the engine body and the engine body, A temperature reaction part of the thermoelement is buried, an opening / closing valve is provided in the middle of the second fuel supply path, and the opening / closing valve is opened / closed by connecting the operating part of the thermoelement to the opening / closing valve. General-purpose engine starter.