JPH0810680Y2 - Vehicle intake intake device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to an intake device for an engine such as a truck.

(Prior Art) Generally, a truck, especially a dump truck, has many opportunities to travel in a dusty environment.
It is desirable to take in a relatively high level of relatively clean air above the surface of the earth, rather than near the surface of the earth, which is rich in dust. Therefore, as shown in FIG. 1, a rear wall of the cab 10 of the truck, that is, a rear panel 12, to which an intake pipe 14 made of a hollow cylindrical body extending in the vertical direction is attached has already been put into practical use. There is. A cap member 16 is provided at the upper end opening of the intake air intake pipe 14 so as to prevent rainwater and fallen leaves from being sucked in. The lower end of the intake air intake pipe 14 is connected via a connecting pipe, an air filter, etc. It is connected to the intake pipe of the engine.

Since the intake intake pipe 14 generally has a large cross-sectional area and a thin wall thickness, it is relatively low in rigidity and intake noise having a frequency proportional to the engine speed is likely to be generated, and this vibration is caused by the cab 10. There is a case where a muffled sound that is transmitted to the vehicle and impairs habitability is generated.

(Problems to be Solved by the Invention) The present invention has been made in view of the above circumstances, and connects a variable-length side branch whose length can be changed according to the engine speed to the intake intake pipe. By providing the intake intake device for a vehicle engine, it is possible to effectively prevent the occurrence of intake noise in a quick response to a change in the engine speed and effectively reduce the muffled noise in the cab. That is the purpose.

(Means for Solving the Problems) In order to achieve the above object, the present invention is directed to an intake pipe made of hollow cylindrical members arranged vertically along a side wall of a cab, and to be arranged along the intake pipe. A side branch having a pipe member whose lower end is communicated with the intake intake pipe, and a plurality of butterfly valves which are arranged at intervals in the pipe member to change the effective length of the pipe member by opening and closing the pipe member. And an actuator for opening and closing the butterfly valve according to the number of revolutions of the engine.

(Operation) According to the present invention, the side branch is provided in parallel with the intake intake pipe vertically arranged along the rear wall of the cabin of the cab and communicates with the intake pipe. A plurality of butterfly valves are provided inside the side branch, and the effective length of the side branch is changed stepwise by opening and closing the corresponding valves of the plurality of butterfly valves by the actuator according to the engine speed. . The intake noise can be effectively reduced by changing the effective length of the side branch so as to match the frequency of the intake noise that changes in proportion to the engine speed.

(Embodiment) An embodiment of the present invention will be specifically described below with reference to the accompanying drawings. (Note that duplicate explanations are omitted for items already described with reference to FIG. 1.) First, in the schematic configuration diagram of FIG. 2 showing an embodiment of the present invention, a hollow having an appropriate cross-sectional shape A pipe member 18 having a circular or other appropriate cross-sectional shape is arranged in parallel along an intake air intake pipe 14 formed of a tubular body and open at both upper and lower ends, and the pipe member 18 has a pipe closing member or a lid whose upper end is fixed. It is closed by a member 20, and the lower end is connected to the lower part of the intake intake pipe 14. Butterfly valves 22 and 24 are arranged in the pipe member 18 at intervals in the vertical direction, and the butterfly valves 22 and 24 are respectively in the open position or the pipe member illustrated by actuators 26 and 28.
It is selectively positioned in one of the closed positions that closes 18. In the illustrated embodiment, the actuators 26 and 28 are single-acting air cylinders, and each air cylinder is connected to a compressed air source 34 via three-way solenoid valves 30 and 32.

The three-way solenoid valves 30 and 32 are the engine shown schematically in the figure.
It is controlled by a controller 40 that receives the signal output of a rotation speed sensor 38 that detects the rotation speed of 36 and supplies the required drive output.

The supply air intake pipe 14 and the pipe member 18 are connected by a connecting member 42.
Preferably, they are integrally connected to each other.

In the above configuration, the intake air of the engine 36 arranged below the cab 10 flows into the intake pipe through the gap between the cap member 16 and the intake intake pipe 14, and the connecting pipe and the air filter (not shown) are shown. And is supplied to the intake pipe 44 of the engine.

On the other hand, when the butterfly valves 22 and 24 in the pipe member 18 arranged in parallel with the intake intake pipe 14 are in the fully open positions shown in the drawing, the pipe member 18 is closed by the lid member, that is, the fixed pipe closing member 20. The side member having the maximum effective length L ₁ is formed by the pipe member and the fixed pipe closing member. Next, when the three-way solenoid valve 30 is energized by the controller 40 and the solenoid valve 32 is maintained in the deenergized state, compressed air is supplied from the compressed air source 34 to the actuator 26 via the solenoid valve 30. The butterfly valve 22 rotates about 90 degrees from the illustrated position to close the pipe member 18. As a result, the pipe member 18 and the upper butterfly valve 22 form a side branch having an intermediate effective length L ₂ . In addition, the controller 40
When the three-way solenoid valve 32 is energized by the three-way solenoid valve 32, the compressed air source 34 supplies it to the actuator 28 through the solenoid valve 32, so that the butterfly valve 24 rotates about 90 degrees from the position shown in the figure to close the pipe member 18. Then, as a result, the side branch having the shortest effective length L ₃ is formed by the pipe member and the lower butter fly valve 24. (In this case, the upper butterfly valve
22 may be located in either the open position shown or the closed position described above. ) Since the main component of the intake noise of the intake intake pipe 14 is the primary explosion component of the engine 36 and is proportional to the engine speed,
The frequency of the noise that causes the muffled noise of the cab 10 is investigated in advance, and the effective lengths L ₁ , L ₂ , and L ₃ of the side branches corresponding to the frequency are set, and the rotation speed of the engine 36 is rotated. By controlling the operation of the three-way solenoid valves 30 and 32 by the controller 40 while detecting by the number sensor 38,
It is possible to effectively reduce the intake noise, and thus effectively reduce the muffled noise of the cab 10.

In the above embodiment, by integrally connecting the intake intake pipe 14 and the pipe member 18 forming the side branch by the connecting member 42, the pipe member 18 acts as a reinforcing member of the intake intake pipe 14. The vibration of the intake intake pipe 14 is suppressed. Further, in the above embodiment, the effective length of the side branch is changed into three types, but the number of stages of change of the effective length of the side branch may be appropriately increased or decreased according to the intake noise frequency that causes the cab noise. You can Further, in the above embodiment, butter fly valves 22,2
As an actuator for displacing 4, any actuator other than the air cylinders 26 and 28 and the motor 54, which are respectively exemplified, can be appropriately adopted.

(Effect of the Invention) As described above, the intake device for a vehicle according to the present invention is
An intake air intake pipe made of a hollow cylindrical body vertically arranged along the side wall of the cab, and a pipe member provided along the intake air intake pipe in parallel with the lower end thereof communicating with the intake air intake pipe. And a side branch having a plurality of butterfly valves arranged at intervals to change the effective length of the pipe member by opening and closing, and an actuator for opening and closing the butterfly valve according to the engine speed. With a simple configuration, the intake noise can be reduced with good response in response to changes in the engine speed, and the muffled noise of the cab can be effectively reduced, and the intake air intake is excellent in durability and inexpensive. A device can be provided, which is practically beneficial.

[Brief description of drawings]

FIG. 1 is a schematic side view of a truck cab to which the present invention is applied, and FIG. 2 is a schematic configuration diagram showing an embodiment of the present invention. 10 …… Truck cab, 12 …… Cab rear wall, 14 ……
Intake intake pipe, 18 ... pipe member, 22, 24 and 46 ... movable pipe closing member, 26, 28 and 54 ... actuator.

Claims (1)

[Scope of utility model registration request] 1. An intake intake pipe formed of a hollow cylindrical body vertically arranged along a side wall of a cab, and a pipe member arranged in parallel along the intake intake pipe and having its lower end communicated with the intake intake pipe. And a side branch having a plurality of butterfly valves arranged at intervals in the pipe member to change the effective length of the pipe member by opening and closing the pipe member, and opening and closing the butterfly valve according to the engine speed. An intake device for a vehicle, comprising an actuator