JPH0313567Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of an air cleaner with a muffler used in an automobile engine.

In the first place, a considerable amount of suction noise is transmitted from an automobile engine to the outside of the vehicle as the intake valve opens and closes, so air cleaners are used to remove dust and attenuate the suction noise generated from the engine. In order to attenuate noise at particularly unpleasant frequencies, insertion tube type mufflers or resonance type mufflers are used.

A conventional example of an insertion tube type air cleaner with a silencer is shown in FIG. In this example, a vertical air cleaner with a dust pan is equipped with a suction quality muffler using the inlet pipe of the air cleaner, and only the muffler portion is shown in cross section. In other words, an insertion tube type air cleaner with a silencer
A' is an air cleaner main body 1 having a dust pan 7 and an outlet pipe 8, in which a silencer S' is disposed.
The muffler S' has a front pipe 6' inserted into the front wall 3' of the case 2' and an inlet pipe 5' inserted into the rear wall 4' of the case 2' in an airtight manner. ' and one end of the front pipe 6' are opposed with a gap C',
Further, a holder 10 fixed to the case 2' is attached to the rigid body part 9. However, this air cleaner A' with a silencer has a noise reduction performance because the length l' of the front pipe 6' is relatively small compared to the distance L from the base of the inlet pipe 5' of the air cleaner body 1 to the tip of the front pipe 6'. This is also disadvantageous, as it requires the holder 10 for reinforcement.

The present invention has been devised to eliminate this drawback, and aims to provide an air cleaner with a muffler that is advantageous in muffling performance and effective in terms of strength even if the dimension of L is the same.

FIG. 1 is a longitudinal sectional view of an air cleaner A with a muffler according to an embodiment of the present invention. The air cleaner body 1 is cylindrical and has an inlet pipe 5 on its upper side.
A hollow case 2 is fixed to the side surface of the air cleaner body 1 around the inlet pipe 5. The two side walls of the case 2, that is, the front wall 3 and the rear wall 4, are provided with openings, and the front pipe 6 is inserted into the opening in the front wall 3, and the inlet pipe 5 is inserted into the opening in the rear wall 4. , hermetically fixed. One end of the front pipe 6 faces the inlet pipe 5 with a gap C inside the case 2, and the case 2, the front pipe 6, and the inlet pipe 5 form an insertion pipe type muffler S. The length of the inlet pipe 5 will decrease, and conversely the length of the front pipe 6 will increase. The length of the front pipe 6 is greater than the length of the inlet pipe 5. In addition, E in the figure is a filter element, 7
is a dust pan, and 8 is an outlet pipe. Further, the front wall may be used as an upper wall or a lower wall. When the engine (not shown) operates, the air necessary for combustion is sucked in from the tip of the front pipe 6, and the silencer S,
The dust enters the air cleaner main body 1 through the inlet pipe 5, and the relatively large-sized dust is transferred to the dust pan 7 by centrifugal force.
The small-sized dust is collected by the filter element E, and only the purified air is sent to the outlet pipe 8.
is introduced into the engine (not shown).

On the other hand, the suction noise propagated from the engine (not shown) enters the air cleaner body 1 through the outlet pipe 8 and is attenuated by the expansion of the pipe, and is further attenuated by the inlet pipe 5, the hollow case 2, and the front pipe 6. It is released into the atmosphere through rapid contraction, rapid expansion, and rapid contraction, resulting in a damping effect due to sound interference.

Comparing the performance of the present invention and a conventional silencer when the distance L from the base of the inlet pipe to the tip of the front pipe is the same, the length l of the front pipe of the present invention is equal to that of the front pipe of the conventional silencer. The front pipe, which is always large compared to the length l′ and is a tail in sound, can be made longer, and the cutoff frequency of the muffler is lowered (the length of the tail significantly affects the frequency characteristics of the damping effect). It also has a large damping effect (giving the same effect), and since the muffler case is integrally attached to the air cleaner body, there is little movement of the muffler itself, and there is no need for special holders.

FIG. 3 is a noise comparison diagram based on an experimental example of the conventional air cleaner and the present invention air cleaner with a silencer, showing that the present invention product is superior to the conventional product.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of the air cleaner with a silencer of the present invention, FIG. 2 is a partial cross-sectional view of the conventional air cleaner, and FIG. 3 is a noise comparison chart between the conventional product and the present invention. A, A'... Air cleaner with silencer, 1... Air cleaner body, S, S'... Silencer, 2, 2'...
...Case, 3, 3'... Front wall, 4, 4'... Rear wall,
5, 5'...Inlet pipe, 6, 6'... Front pipe, 8...
...Exit pipe, 10...Holder, E...Filter element, l, l'...Length of front pipe (tail pipe).

Claims (1)

[Scope of utility model registration request] One side wall of a hollow case having openings in two side walls is fixed to the side surface of the main body around the inlet pipe provided in the cylindrical air cleaner main body, and the inlet pipe is airtightly attached to the opening in the one side wall. At the same time, the front pipe is inserted and secured airtightly into the opening in the other side wall of the case, and one end of the front pipe and the end of the inlet pipe are opposed within the case, and the length of the front pipe is set to the same length as the inlet pipe. An air cleaner with an insertion tube type silencer that is larger than its length.