JP2513677Y2 - Air cleaner for internal combustion engine - Google Patents

Description

TECHNICAL FIELD The present invention relates to an air cleaner for an internal combustion engine.

2. Description of the Related Art Conventionally, it has been known that a long intake passage is effective as a means for reducing intake noise of an air cleaner. For example, in the invention of Japanese Utility Model Laid-Open No. 61-99665 filed by the applicant of the present application, the intake passage is made long by being provided along the outer periphery of the air cleaner case.

However, the conventional air cleaner having a long intake passage has a disadvantage that the air cleaner is relatively large and the engine is accordingly large in size. For example, in the invention of the above publication, there is a drawback that the outer shape of the case of the air cleaner becomes larger by the amount of the intake passage, and due to the larger size, it protrudes from the outer shape of the engine. Further, the case expands outward in this way. When attached to the engine body, the weight of the overhanging portion becomes heavy, and the amplitude of the air cleaner due to the vibration of the engine may increase, which may result in an increase in noise. Further, since the suction port of the suction passage is on the outside, there is the inconvenience that the radiation sound from the passage is directly radiated to the outside.

This invention has been made for the purpose of realizing an air cleaner that eliminates these conventional drawbacks.

Means for Solving the Problems In order to solve the above problems, in the present invention, in an air cleaner attached to an engine body, a long intake passage bent along the back surface of the air cleaner case is formed between the air cleaner and the engine body wall surface. In addition, the suction port of the suction passage is opened at the upper portion of the back surface of the air cleaner case.

Operation According to the above invention, the intake passage is provided on the back surface of the case of the air cleaner, and the intake passage is disposed in the space between the engine body to which the air cleaner is attached and the case body. Further, the suction port of the suction passage is arranged above the space.

Embodiments FIGS. 1 to 3 show the structure of an air cleaner according to the present invention. In the drawings, reference numeral 1 is an air cleaner case formed in a rectangular shape when viewed from the front, and the air cleaner case 1 is a schematic plate. The base 2 is shaped like a bowl, and the bowl-shaped case body 3 is attached to the base 2 from the outside by fitting into a groove on the outer circumference of the base 2. At the center of the base 2, a cylindrical boss 5 having a screw hole 4 is integrally formed from the end surface on the case body 3 side. The tip of a bolt 6 screwed into the screw hole 4 is attached to the center of the case body 3. The wing nut 7 is screwed into the bolt hole 8 and is fastened and fixed to each other. At that time, the case body 3
An annular element 9 installed inside is held by a support plate 10 that is fitted onto the bolt 6 and clamped and fixed together with the case body 3 so as to be sandwiched between the base 2 and the case body 3. An outlet 11 opening to the rear surface side is formed near the center of the base 2 so as to communicate with a chamber 12 inside the element 9. 13 is the intake passage
A passage member for forming 14 is formed in an L-shape that follows the outer shape of the air cleaner case 1 as shown in FIG. 1, and is formed in a semicircular cross section divided in half along the passage direction. There is. On the other hand, as shown in FIG.
A groove 15 having a semicircular cross-section that is paired with the passage member 13 is integrally formed on the back surface of the base member 13. The passage member 13 is fixed to the back surface of the base 2 by welding or caulking so as to match the groove 15. , Long suction passage 14 bent in L shape on the back side
Is formed. At this time, the intake passage 14 is formed from the upper end of the air cleaner case 1 along one end in the left-right direction, and the upper end is the intake port 16 and the air cleaner case is provided at the lower end. An outlet 18 is formed which communicates with a chamber 17 on the outer peripheral side of the element 9 in the apparatus 1. In this way, the suction port 16 is formed at the upper end, so that when the engine body is installed on the ground or the like, it is difficult to suck in dust or the like that winds up from the ground or the like.

4 and 5 show the mounting state of the air cleaner 21. The outlet of the base 2 is aligned with the intake port 24 of the cylinder head 22 on the wall surface of the cylinder head 22 opposite to the exhaust muffler 23. So that it is installed directly. Reference numeral 25 denotes a fuel tank arranged on the back side of the engine body 26. The intake passage 14 is arranged in the space between the air cleaner case 1 and the wall surface of the cylinder head 22 so that the upper end inlet 16 thereof faces the rear direction.

In the above, the air that has entered the passage 14 through the inlet 16 enters the chamber 17 outside the element 9 inside the case 1 through the outlet 18 at the lower end, and after passing through this element 9 the inside chamber 12
It enters and is sucked into the intake port 24 from the outlet 11 of the base 2. In this embodiment, the case body 3, the base 2 and the passage member 13 are made of resin,
It has a structure that further reduces intake noise. Passage member 13
May be integrally formed with the base 2.

Effect of the Invention As described above, in this invention, the long intake passage and its intake port are provided in the space between the back surface of the air cleaner case and the wall surface of the engine body. It can be suppressed, and there is no drawback that the air cleaner sticks out of the outer shape of the engine. Moreover, since the suction port of the suction passage is located on the back side of the air cleaner main body, it is possible to reduce the emission of radiation sound from the suction port to the outside and to reduce noise. Further, since the suction port is formed in the upper part of the back surface of the case, when the engine body is placed on the ground or the like, it is difficult to suck dust or the like that winds up from the ground or the like. Furthermore, since the passage part comes to the back side which is the fixed side to the engine body, the weight of the tip part when mounted in the overhang state is reduced, and the amplitude of the air cleaner due to the vibration from the engine body is made smaller than before. , A structure with less noise can be obtained.

[Brief description of drawings]

FIG. 1 is a front view of the air cleaner of the present invention seen from the back side, and FIG. 2 is a cross-sectional view showing the case body in a longitudinal section,
1 is a vertical cross-sectional view taken along the line AA of FIG. 1, FIG. 4 is a plan view of an engine having an air cleaner attached, and FIG.
Similarly, it is a longitudinal side view of a main part of the entire engine. 1 ... Air cleaner case, 14 ... Suction passage, 16 ... Suction port,
21 ... Air cleaner, 26 ... Engine body.

Claims (1)

(57) [Scope of utility model registration request] 1. An air cleaner attached to an engine body, wherein a long intake passage bent along the back surface of the air cleaner case is formed between the air cleaner and the wall surface of the engine body, and the intake port of the intake passage has an air cleaner case. An air cleaner for an internal combustion engine, characterized in that it is opened at the upper part of the back surface of the above.