JPH06207507A - Automatic decompressor device for engine - Google Patents

Abstract

PURPOSE:To reduce the number of a parts so as to simplify structure, in an automatic decomperessor device for interlocking a decomp and a recoil starter. CONSTITUTION:The end part 10a of a knob 10 connected to the pulling braid 18 of a recoil starter is stored in a knob end part receiver 30. An operating rod 32 for a decompressing is connected to the end part of the knob 10, and a valve 67 and a coil spring 8 are provide aside thereon. When an engine is started, the knob 10 of the recoil starter is pulled, the end part of the knob 10 is detached from a knob end part receiver 30, and the operating rod 32 and the valve 67 are moved in the opening position direction by that compressed coil spring 8 so as to open a pressure reducing passage 1. Furthermore, pressure in a cylinder passes the pressure reducing passage 1, and it passes over to a scavenging port side so as to reduce the starting torque of the recoil starter, namely, reduce tractive force of a pulling braid 18. When the engine is started and the pulling braid 18 is rewound, the end part of the knob 10 is stored in the knob end part receiver 30, and the operating rod 32 and the valve 67 are moved in closing position direction opposing to the coil spring 8 so as to close the pressure reducing passage 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic decompression device for an engine, which interlocks a decompression device with a recoil starter.

[0002]

2. Description of the Related Art A conventional engine automatic decompression device (as disclosed in Japanese Utility Model Laid-Open No. 56-29238).
6 and FIG. 7, before the engine is started, the drawstring 18 is pulled in the direction of arrow A by the rewinding device (not shown) of the recoil starter 9, and as shown in FIG. The tip 10a is pressed against the knob receiver 11 against the coil spring 19. On the other hand, the valve 7 is pushed to the left by the coil spring 8, and the pressure reducing passage 1 is closed by the valve 7. At this time, the engaging portion 21 of the connecting rod 21
a and the extension portion 20 of the knob receiver 11 are not engaged with each other.

From this state, when starting the engine, the knob 10 of the recoil starter 9 is pulled, the spring force of the coil spring 19 pulls the knob receiver 11 together with the drawstring 18, and the stopper 16 on the knob receiver 11 side is recoiled. While abutting against the stopper 17 on the starter 9 side, the extension portion 20 of the knob receiver 11 and the engaging portion 21a of the connecting rod 21 are engaged with each other, and the valve 7 is moved to the right through the connecting rod 21. Open the decompression passage 1.

As a result, the pressure in the cylinder is reduced by the pressure reducing passage 1.
After that, the starting torque of the recoil starter 9, that is, the pulling force of the drawstring 18 is reduced. The stroke range of the knob receiver 11 (operating range of the valve 7) at this time is h. When the drawstring 18 is pulled out as described above, the recoil starter 9 operates to start the engine.

When the drawstring 18 is rewound, the knob receiver 11 is pressed by the tip 10a of the knob 10, the extension 20 of the knob receiver 11 is separated from the engaging portion 21a of the connecting rod 21, and the valve 7 is coiled. The spring 8 restores the original position, and the pressure reducing passage 1 is closed by the valve 7.

[0006]

The conventional automatic decompression device for an engine shown in FIGS. 6 and 7 has a large number of parts, a complicated structure, and a simple structure. . The present invention is proposed in view of the above problems, and an object of the present invention is to provide an automatic decompression device for an engine that can reduce the number of parts and simplify the structure.

[0007]

In order to achieve the above object, the present invention provides a pressure reducing passage communicating with a combustion chamber in a cylinder, and an elastic member for biasing the valve and the valve in the opening direction in the pressure reducing passage. And the operating rod that contacts the end of the knob is connected to the valve, a knob receiving member that houses the end of the knob is installed on the recoil starter side member, and the operating rod is pulled by pulling the knob. It is configured to move the valve toward the open position of the pressure reducing passage via the.

A bracket projecting from the engine body may be used as the knob receiving member.

[0009]

The automatic decompression device for the engine of the present invention is constructed as described above, and the pulling cord is pulled by the rewinding device of the recoil starter so that the end of the knob is housed in the knob end receiver. On the other hand, when the knob of the recoil starter is pulled when starting the engine from the state where the operation rod and the valve move toward the closed position against the coil spring by the end portion of the knob and the decompression passage is closed, The end of the knob is disengaged from the knob end receiver, and the compressed coil spring moves the operating rod and valve toward the open position to open the decompression passage and the pressure in the cylinder passes through the decompression passage. The starting torque of the recoil starter, in other words, the pulling force of the drawstring is reduced by passing through to the scavenging port side or the like. The drawstring is pulled out as it is, the engine is started by the operation of the recoil starter, and when the drawstring is rewound, the end of the knob is stored again in the knob end receiver, and the operating rod and the valve are coil springs. And moves toward the closed position to close the decompression passage.

[0010]

【Example】

(First Embodiment) Next, an automatic decompression device for an engine of the present invention will be described with reference to a first embodiment shown in FIGS. 1 to 4. FIG. 1 is a front view of the engine and FIG.
3 is a side view taken along the line, and FIG. 3 and FIG. 4 are longitudinal side views taken along the line B in FIG.

In FIG. 1, 40 is a fuel tank, 41 is an air filter, 42 is a spark plug, 44 is an exhaust device, and 9 is a recoil starter. 1 and 2, 60 is a carburetor, 61 is an insulator provided between the carburetor 60 and the engine body, 45 in FIGS. 1 to 4 is a bracket for covering the insulator 61, and 30 is attached to the bracket 45. Knob end receiving (knob receiving member), 10 is a knob, 10a is a knob 1
It is the end of 0.

3 and 4, 4 is a cylinder head, 5 is a cylinder block, and the spark plug 42 is attached to the cylinder head 4. Reference numeral 23 denotes a piston, which forms the combustion chamber 2 in the cylinder block 5 and causes the fuel to be compressed and burned. Reference numeral 1 in FIGS. 3 and 4 denotes a pressure reducing passage provided in the cylinder block 5.
Extends from the combustion chamber 2 to a scavenging port (not shown), and exhausts the internal pressure of the cylinder to the scavenging port side when the engine is started. The decompression passage 1 may extend to the exhaust port, the inside of the crankcase, the outside air, or the like.

Reference numeral 6 is a valve hole provided in the cylinder block 5, and the valve hole 6 communicates with the pressure reducing passage 1. Reference numeral 67 is a valve, and 32 is an operation rod connected to the valve 67. The valve 67 is inserted into the valve hole 6 from the outside of the cylinder block 5 to open and close the decompression passage 1. . Reference numeral 8 is a coil spring (elastic member) interposed between the inner end of the valve hole 6 and a flange portion provided on the valve 67, and the coil spring 8 opens the valve 67 (opens the pressure reducing passage 1 to open). Position).

On the other hand, the rewinding device (not shown) for the recoil starter 9 pulls the drawstring 18 in the direction of arrow C, and the end 10a of the knob 10 is housed in the knob end receiver 30. The knob end receiver 30 is provided with a hole 31 into which the tip end of the operation rod 32 is removably fitted. The same reference numerals are used for the same parts as those of the conventional automatic decompression device.

Next, the operation of the automatic decompression device for the engine shown in FIGS. 1 to 4 will be specifically described. FIG. 3 shows a state before the engine is started. At this time,
By the rewinding device (not shown) of the recoil starter 9,
The drawstring 18 is pulled in the direction of arrow C, and the end 10 a of the knob 10 is housed in the knob end receiver 30. In addition, the operating rod 32 and the valve 6 are controlled by the end 10 a of the knob 10.
7 moves toward the closed position against the coil spring 8 to close the decompression passage 1.

From this state, when starting the engine, when the knob 10 of the recoil starter 9 is pulled, the knob 10
End portion 10a of the control rod 32 is disengaged from the inside of the knob end portion receiver 30 (see FIG. 4), and the compressed coil spring 8 causes the operating rod 32 to move.
And the valve 67 moves toward the open position to open the pressure reducing passage 1, the pressure in the cylinder escapes to the scavenging port side via the pressure reducing passage 1, and the starting torque of the recoil starter 9, in other words, the drawstring 18 The traction force of is reduced.

When the drawstring 18 is pulled out as it is, the engine is started by the operation of the recoil starter 9 and the drawstring 18 is rewound, the end 10a of the knob 10 is housed in the knob end receiver 30. , Operating rod 32 and valve 67
Moves toward the closed position against the coil spring 8 and the decompression passage 1 is closed. (Second Embodiment) FIG. 5 shows another embodiment in which the cover of the recoil starter 9 is extended upward to form a bracket 46 and the bracket 46 is used as a knob end receiver. Also in this embodiment, the same operation as described above is achieved.

[0018]

As described above, the automatic decompression device for an engine of the present invention operates the operating rod and the valve through the end portion of the knob, so that the number of parts can be reduced and the structure can be simplified.

[Brief description of drawings]

FIG. 1 is a front view showing a first embodiment of an automatic decompression device for an engine of the present invention.

FIG. 2 is a side view taken along the line A of FIG.

FIG. 3 is an operation explanatory view showing a closed state of a decompression passage of the automatic decompression device, taken along the line B in FIG.

FIG. 4 is an operation explanatory view showing an open state of the decompression passage of the automatic decompression device, taken along line B in FIG.

FIG. 5 is a front view showing a second embodiment of the automatic decompression device.

FIG. 6 is an operation explanatory view showing a closed state of the pressure reducing passage of the conventional automatic decompression device for an engine.

FIG. 7 is an operation explanatory view showing the decompression passage open state of the automatic decompression device.

[Explanation of symbols]

1 Decompression Passage 2 Combustion Chamber 5 Cylinder Block 8 Elastic Member 9 Recoil Starter 10 Knob 10a End of Knob 32 Operation Rod 30 Knob Receiving Member 45 Recoil Starter 9 Side Member (Bracket) 46 Bracket 67 Valve

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Tomiya Kato No. 1 Takamichi, Iwazuka-cho, Nakamura-ku, Nagoya-shi, Aichi Mitsubishi Heavy Industries, Ltd. Nagoya Machinery Works (72) Inventor Hiroyoshi Kawachi Iwatsuka, Nakamura-ku, Aichi No. 1 in Takachi, Machiji, Nagoya Machinery Works, Mitsubishi Heavy Industries, Ltd. (72) Inventor: Makoto Kawai 47, Kitagawada, Oyama, Chiaki-cho, Ichinomiya-shi, Aichi Yasuda Giken Co., Ltd.

Claims (2)

[Claims] 1. A decompression passage communicating with a combustion chamber is provided in a cylinder, a valve and an elastic member for urging the valve in an opening direction are provided in the decompression passage, and an operating rod abutting against an end of a knob is provided in the valve. A knob receiving member for connecting and storing the end portion of the knob is installed on a member on the recoil starter side, and by pulling the knob, the valve is moved via the operation rod toward the decompression passage open position direction. The automatic decompression device for the engine characterized by the above. 2. A bracket which projects from the engine body is used as the knob receiving member.
Automatic decompression device for the described engine.