JPS58101213A - Engine - Google Patents

Abstract

PURPOSE:To reduce the number of parts and to improve the productivity by providing a crank case and a cavity forming an exhaust muffler in one body on a block-like non-metallic inorganic material so that many molds and press dies are not required. CONSTITUTION:A block body 26 is produced with concrete as non-metallic inorganic material in one body. A suction chamber 28, first expansion chamber 30, resonance chamber 32, and second expansion chamber 34 are formed in the block body 26, and a crank case 36 is formed above individual chambers 28-34. Light weight forming concrete layers 37, 38 are formed inside the first and second expansion chambers 30, 34. Air passages 39, 40 penetrate the block body 26 in the back-and-forth direction and form an adiabatic air layer.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an engine in which a crank chamber and an exhaust muffler are integrally formed using a non-metallic inorganic material such as concrete.

Generally, in a heat engine (hereinafter referred to as engine), the engine body, which consists of a crankcase, piston, cylinder body, cylinder head, crankshaft, etc., and an exhaust silencer are made separately. This makes it difficult for the heat from the exhaust silencer to be transferred to the engine body, resulting in a decrease in engine output due to the heat.
Inconveniences such as poor lubrication are less likely to occur.

-77. In conventional engines, the exhaust muffler and crankcase were usually made of metal, so the thermal conductivity of gold 4 was poor, making it impossible to make the engine body and exhaust muffler in one piece. This not only requires a large number of molds, such as crankcase molds and silencer press molds, but also requires processing such as welding, resulting in a significant increase in the number of man-hours.

Another disadvantage was that the engine itself and the muffler were separate, making the overall engine larger.

This invention was made in view of these circumstances,
To provide an engine in which an engine body and an exhaust muffler are integrated using a material with excellent heat insulation properties, thereby reducing the number of parts, significantly increasing productivity, and further downsizing the entire engine. With the goal.

In order to achieve this object, the present invention provides a crank chamber and a cavity forming an exhaust muffler integrally provided in a block-shaped non-metallic inorganic material. The present invention will be described in detail below based on the illustrated embodiments.

The drawings show an embodiment in which the invention is applied to a portable engine generator, with FIG. 1 being a front view thereof, and FIG. 2 being a right side view thereof.
Figure 3 is a cross-sectional view taken along the line ■-- in Figure 1. Figure 4 is a front view of the block main body in which the crankcase, exhaust muffler, intake chamber, etc. are integrally formed. Figure 5 is the ■- line in Figure 1. ■ Line sectional view, No. 6.7゜8 is M-41 in Fig. 4.
9 is a sectional view taken along line 1--2, and 2--2, and FIG. 9 is a sectional view taken along line 1--2 in FIG.

In Fig. 1.2.3, reference numeral 10 denotes a two-stroke single-cylinder engine main body, 12 a generator driven by this engine main body 10, and 14 a recoil type starter (Fig. 2). As shown in FIG. 3, this recoil type starter 14 is provided with a blower fan 16, and the cooling air sent out by the blower fan 16 is guided to a cover l5 (il, FIG. 3) to the engine body l.

is forced to cool down. The generator 12 protrudes forward from the engine body 10, and has two legs 20 (, 20a) at its front end that extend in the y direction as shown in Figure 1.2.
, 20b) are fixed and tailed.

In FIGS. 1 to 3, 22 is an instrument panel, and 24 is a fuel tank. This fuel tank 24 contains a mixed oil consisting of gasoline and lubricating oil.

26 is a block body, and this block body 26 is integrally made of concrete as a non-metallic inorganic material. The block body 26 has intake chambers 2 in sequence from the right side in Fig. 4.
8, a first expansion chamber 3o, a resonance chamber 32, and a second expansion chamber 34 are formed, and above each of these chambers 28 to 34 is a crank chamber 3.
6 is formed. All of these chambers 28 to 36 are open to the front side. Note that the first thing. A lightweight foamed concrete (hereinafter referred to as ALC) layer 37 is provided on the inner surface of the second expansion chamber 30.34.
．． 38 is formed. That is, the ALC layers 37 and 38 are formed by making a box from ALC in advance and casting this ALC box when manufacturing the block body 26.

The ALC layers 37 and 38 serve to enhance sound absorption. 39 and 40 are air passages formed between the intake chamber 28 and the first expansion chamber 30, and between the first and second expansion chambers 30 and 34 and the crank chamber 36, respectively. These air passages 3
9° 40 penetrates the block body 26 in the front-rear direction and forms a heat insulating air layer.

An intake pipe 42 that protrudes to the right communicates with the intake chamber 28, as shown in FIG. 44
is attached, and a cover plate 46 is attached from the front side. This cover plate 46 has an air intake hole 48 opened therein.

1st. A cover material 50 made of a concrete block is attached to the second expansion chamber 30, 34 and the resonance chamber 3'2 from the front. As is clear from FIGS. 1.2, 6, and 7.8, an exhaust pipe 52 that protrudes to the left is embedded in this lid member 50, and the right end of this exhaust pipe 52 connects to the first expansion chamber 30. They communicate (Figure 6). 54 and 56 are exhaust passages formed between the block body 26 and the base of the lid member 50;
4 is the first. The second expansion chamber 30.34 is communicated with the exhaust passage 56, and the exhaust passage 56 communicates with the resonance chamber 32 (FIG. 4.6.7). Thus, in this embodiment, a plurality of cavities are formed between the concrete block body 26 and the cover material 50, that is, the first cavity. A second expansion chamber 30.degree. 34 and a resonance chamber 32 are formed, which constitute an exhaust muffler.

In Figure 4.8.9, 58.60 is block body 2
The rear end of the exhaust passage 58 is connected to the second expansion chamber 34 through a pipe 62, and the rear end of the exhaust passage 60 is opened to the back surface of the block body 26. The front ends of both of these exhaust passages 58 and 60 communicate with each other through a passage 64 formed between the base surfaces of the block body 26 and the cover member 50. As a result, the exhaust from the engine body lO is
, 1st degree second expansion chamber 30.34. It is discharged to the rear of the block body 26 through exhaust passages 58,60.

Next, the engine body IO will be explained. Block body 2
6, the crank chamber 36 formed in FIG. 6 has a wide opening at the front, and the crank chamber 36 on this opening side
The inner circumferential surface 66 has a slightly tapered diameter expanding toward the front. Further, a substantially cylindrical boss 68 made of metal is integrally embedded in the block body 26, and this boss 68 supports a crankshaft 70, which will be described later.

In FIG. 3, 70 is a crankshaft, and 72 is a connecting rod. These assemblies are installed into the crank chamber 36 through the opening of the crank chamber 36, and the rear part of the crankshaft 70 is supported pivotally on the boss 68 by a bearing 74. do. 76 is a crankcase lid material made of concrete block,
A metal substantially cylindrical boss 78 is integrally embedded in the center thereof. This cover member 76 is attached to the opening of the crank chamber 36 from the front side of the block body 26, and at this time, the crankshaft 7
0 is supported on the boss 78 by a bearing 80.

82 is a piston attached to the upper end of the connecting rod 72;
84 is a cylinder body, 86 is a cylinder head,
The cylinder body 84 and cylinder head 86 are fixed to the block body 26 by bolts 88 (see FIG. 4) implanted in the block body 26. 90 in Figure 3
9 is a scavenging passage, and 92 is a spark plug.

Note that the cover material 76 attached to the crank chamber 36 of the block body 26 and the base surface 94 of the block body 26 are connected to the cylinder body 84 and the block body 26 as shown in FIG.
and the base surfaces 94 .
96 do not intersect with each other. In other words, since the dimensional accuracy of non-metallic inorganic materials such as concrete is generally poorer than that of metallic materials, these two base surfaces 94,
If the numbers 96 intersect, there is a risk that the sealing performance will deteriorate. In this embodiment, these pedestals 94 and 96 were joined via a gasket so that they did not intersect with each other.
Sealing can be performed reliably.

In FIG. 1.3, 100 is a carburetor, and this carburetor 100 has a bolt 10 installed in the block body 26.
2 (FIG. 4), it is attached to the block body 26 via the reed valve 104. Further, 104 is a duct connecting the intake pipe 42 and the carburetor 100. In FIG. 1, reference numeral 108 indicates the exhaust pipe 5 for directing the exhaust gas from the engine lO.
This is the exhaust pipe that leads to 2.

Next, the operation of this embodiment will be explained. First, the main switch is turned on and the engine body 10 is manually started using the recoil starter 14. Intake air is provided through an intake hole 48, a filter 44, an intake chamber 28, an intake pipe 42, a duct 106,
It passes through the carburetor 100 and the reed valve 104 and is sucked into the crank chamber 36 as the piston 82 rises. vaporizer 1
The air-fuel mixture consisting of the fuel mixed at 00 and the intake air is pre-pressurized within the crank chamber 36 as the piston 82 descends, and then enters the combustion chamber through the scavenging passage 90 and is combusted.

The exhaust gas of the engine body 10 passes through the exhaust pipe 108.52 and enters the first expansion chamber 30, where it is expanded.

The exhaust gas is then throttled through the exhaust passage 54, enters the second expansion chamber 34, and expands again. In other words, the exhaust gas is discharged from these expansion chambers 30.
．． They interfere while expanding within 34, and the exhaust noise is attenuated.

Meanwhile, the resonance chamber 32 absorbs the vibration energy of the exhaust gas. As a result, the exhaust sound is formed in these expansion chambers 30, 34, resonance chambers 32, etc. and is then exhausted through exhaust passages 58, 60. Furthermore, since the block body 26 is made of concrete which has excellent not only sound insulation and vibration absorption properties but also sound absorption properties, the exhaust noise silencing effect is further improved.

In this embodiment, since the ALC layer is formed on the inner surface of the expansion chamber 30, 34, the exhaust sound can be further attenuated due to the high sound absorbing property of the ALC layer itself.

In addition, concrete itself has very good heat insulation properties, but in this embodiment, air passages 39.4 are also provided in the block body 26.
0, it becomes even more difficult for the heat of the exhaust gas to be transmitted to the intake chamber 28 and the crank chamber 36. Therefore, there is no risk that the intake chamber 28 or the crank chamber 36 will overheat, and problems such as performance deterioration and poor lubrication due to heat can be reliably prevented.

In the above embodiments, concrete was used as the non-metallic inorganic material, so not only can it be easily manufactured by simply pouring concrete into a chamber and hardening it, but the material is also inexpensive. However, it goes without saying that this invention can also be applied to concrete.

As described above, in this invention, the crank chamber and the cavity forming the exhaust silencer are integrally provided in the block-shaped non-metallic inorganic material, so it not only eliminates the need for many molds and press molds, but also This eliminates the need for processing such as welding, reduces the number of parts, and significantly improves productivity. In addition, non-metallic inorganic materials have excellent heat insulation properties, so the heat from the silencer will not be transferred to the engine itself and cause problems such as reduced output performance or poor lubrication. Furthermore, since the engine body and the exhaust muffler are integrally formed, the overall size of the engine can be reduced.

[Brief explanation of drawings]

Fig. 1 is a front view showing an embodiment of the present invention, Fig. 2 is a right side view, Fig. 3 is a sectional view taken along the line -1 in Fig. 1, and Fig. 4 is a front view of the block body. Figure 5 is a sectional view taken along the line V-V in Figure 1, Figure 6.7. The figure is a sectional view taken along the line EK- in FIG. 10・°・Engine body, 26...Block body, 3
0... First expansion chamber as a cavity, 32... Resonance chamber as a cavity, 34... Second expansion chamber as a cavity, 36... Crank chamber, 5o... Lid material . Patent Applicant Yamaha Motor Co., Ltd. 1x' (Representative: Patent Attorney Yama 1) Wen Xiong, 1°not % 6 Figure % 7 Figure % 6 Written Procedure Amendment @ March 10, 2017 Commissioner of the Patent Office Island 1) Spring Tree 1 Display of the case 1982 Patent Application No. 199041 2 Name of the invention Engine 3 Person making the amendment Relationship to the case Patent applicant 6 Number of inventions increased by the amendment 〇As shown in the attached sheet. (Attachment) 8. Contents of the amendment (In the 1st specification, page 4, line 12, "lightweight foamed concrete" is amended to read "lightweight foamed concrete, which is a type of lightweight porous material.") (2) The same book, page 4, line 17, 1, "39.40 is" is amended as follows.
Note that the layer may be formed of various lightweight porous materials instead of ALC. 3θ, 40” (3) In the same book, page 8, line 6, “dimensional accuracy” is corrected to “one-plane accuracy.” (4) In the same book, page 17, r104J is corrected to rl 06J. (5) Correct Figure 1 as indicated in red on the attached sheet. (6) Section 3.6, 8. Correct the figure as attached. Above Figure 1A3 Figure 6

Claims (1)

[Claims] An engine characterized in that a crank chamber and a cavity forming an exhaust muffler are integrally provided in a block-shaped non-metallic inorganic material.