JP2513230B2 - Clog detecting device for air cleaner of internal combustion engine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a clogging detection device for an air cleaner of an internal combustion engine that is mainly installed in an automobile.

[Prior Art] Conventionally, an air cleaner for an internal combustion engine, which is mainly mounted in an automobile, filters the air in which hard dust is suspended and supplies clean air to the internal combustion engine, and the dust causes wear of various parts of the internal combustion engine. Is being prevented. However, when the filter element of the air cleaner is clogged due to the adhesion of dust, the performance of the internal combustion engine deteriorates. Therefore, it is necessary to periodically replace or clean the filter element.

Due to this need, there is a device for detecting clogging of an air cleaner of an internal combustion engine that automatically detects clogging of an air cleaner of the internal combustion engine (Japanese Utility Model Publication No. 59-36688 and Japanese Utility Model Publication No. 60-729).
69 publication).

[Problems to be Solved by the Invention] In these clogging detection devices for an air cleaner of an internal combustion engine, as the filtration element clogging of the air cleaner progresses, the intake negative pressure of the internal combustion engine is reduced by the suction action of the internal combustion engine. By utilizing the increasing value, the clogging of the filter element of the air cleaner is detected when the clogging limit value (operating set negative pressure value) is exceeded.

However, the flow of air in the intake pipe of the internal combustion engine is not a steady flow, but pulsating pressure. Therefore, the negative pressure in the intake pipe is pulsating. Therefore, there is a problem that the clogging detection device operates in a region where the negative pressure is momentarily large due to the negative pressure pulsation. Therefore, it is uneconomical to replace the filtration element which is still usable. Also,
If it is not affected by pulsation, the diaphragm is generally large, the spring constant is large, and the structure inside the clogging detection device is large to attenuate the pulsation. The current situation is not possible.

An object of the present invention is to provide a clogging detection device for an air cleaner of an internal combustion engine that prevents malfunction due to pulsation of atmospheric pressure.

[Means for Solving Problems] A clogging detection device for an air cleaner of an internal combustion engine according to the present invention includes a negative pressure chamber communicating with an intake passage on a downstream side of a filter element of the air cleaner that supplies clean air to the internal combustion engine. And when the negative pressure in the negative pressure chamber exceeds a predetermined negative pressure,
In the clogging detection device that detects clogging of the filtration element, a configuration is provided in which a negative pressure pulsation damping means is provided between the intake passage and the negative pressure chamber.

[Operation and Effect of the Invention] The clogging detection device for an air cleaner of an internal combustion engine of the present invention has the following operation and effect due to the above configuration.

Since the negative pressure pulsation damping means is provided between the negative pressure chamber communicating with the intake passage on the downstream side of the filter element of the air cleaner and the intake passage, the limit value of clogging due to negative pressure pulsation is reached. It is possible to prevent erroneous operation such as previous operation and accurately detect the replacement time or cleaning time of the filter element of the air cleaner.

[Embodiment] An embodiment of a clogging detection device for an air cleaner of an internal combustion engine of the present invention will be described with reference to the drawings.

FIG. 1 and FIG. 2 show a clogging detection device (hereinafter referred to as a clogging detection device) of an automobile ecleaner to which a first embodiment of the clogging detection device for an air cleaner of an internal combustion engine of the present invention is applied.

The clogging detection device 1 includes a housing 2, a negative pressure servo 3 connected to the housing 2, a negative pressure pulsation between a negative pressure chamber 31 of the negative pressure servo 3 and an intake pipe 14 (hereinafter referred to as pulsation pressure). ) Of the pulsation pressure damping valve 4 which is a damping means, and a clogging warning lamp 16 which is a means for allowing the user to recognize clogging of the filter element 13a of the air cleaner 13 by the battery 15.

The housing 2 includes a valve chamber 21 formed therein, a negative pressure servo connection portion 22 which is an intake passage connected to the negative pressure servo 3 by screwing, and a suction pipe 14 side from the negative pressure servo connection portion 22. The intake pipe connecting portion 23 is formed and connected to the intake pipe 14 by screwing. A nozzle 24 that connects the valve chamber 21 and the intake pipe 14 on the downstream side of the air cleaner 13 is formed in the intake pipe connecting portion 23. Also, the negative pressure servo connection part of the housing 2
A seal member 25 composed of an O-ring is attached between 22 and the negative pressure servo 3.

The negative pressure servo 3 includes a negative pressure chamber 31 communicating with the intake pipe 14 between the intake port 12 of the internal combustion engine 11 and the filter element 13a of the air cleaner 13, and the negative pressure in the negative pressure chamber 31 is lower than a predetermined negative pressure. A diaphragm 32 that operates to be displaced toward the intake pipe 14 when increased, a casing 33 that houses the diaphragm 32, a spring 34 that biases the diaphragm 32 in a direction away from the intake pipe 14 via a metal retainer 34a, and the diaphragm 32. The operation switch 35 is turned on and off by the operation of.

The casing 33 is the negative pressure servo connection portion 22 of the housing 2.
A main body case 36 connected to the main body case 36, a cover 38 that is connected to the main body case 36 by caulking, and the inside is an atmosphere chamber 37, and is fixed between the main body case 36 and the cover 38. It comprises a holding member 39 for slidably holding an operating rod 32a for connecting the.

The operation switch 35 is provided with a power supply side connection fitting 35c having a contact 35a at the tip and a power supply side terminal 35b connected to the battery 15 at the other end, and a predetermined gap with the power supply connection fitting 35c. Contact lamp 35d and the other end is clogged Warning lamp 16
And a lamp-side connection fitting 35f which is a lamp-side terminal 35e connected to the.

The power supply side connection fitting 35c is connected to the diaphragm 32 via the operation rod 32a. The negative pressure in the negative pressure chamber 31 increases,
When the pressure becomes equal to or higher than a predetermined negative pressure, the urging force of the spring 34 is overcome, and the diaphragm 32 moves a predetermined distance in a direction toward the intake pipe 14 (rightward in FIG. 1), thereby causing the operating rod 32a.
The power supply side connection fitting 35c is connected to the lamp side connection fitting 35f via. When the negative pressure in the negative pressure chamber 31 is lower than a predetermined negative pressure, the power supply side connection fitting 35c is separated from the lamp side connection fitting 35f because the diaphragm 32 is in the position shown in FIG. 1 due to the biasing force of the sprig 34. Inside the main body case 36, a hole 36a that connects the valve chamber 21 and the negative pressure chamber 31 is formed.

The pulsation pressure damping valve 4 is provided between the valve chamber 21 of the housing 2 and the negative pressure chamber 31 of the negative pressure servo 3, and the valve chamber of the housing 2 is provided.
21 and the valve body 45 which is biased by the spring 44 in the direction in which the negative pressure chamber 31 of the negative pressure servo 3 does not communicate, and the hole of the main body case 36.
An adjusting screw 46 fastened in 36a, a valve chamber 21 of the housing 2 and a negative pressure chamber 31 of the negative pressure servo 3 formed on the adjusting screw 46.
And a hole 47 communicating with and.

The operation of the clogging detection device 1 of this embodiment will be described with reference to the drawings.

When the internal combustion engine 11 operates, the intake negative pressure of the intake pipe 14 on the downstream side of the filtration element 13a of the air cleaner 13 is transmitted to the valve chamber 21 through the nozzle 24 of the housing 2 of the clogging detection device 1. The negative pressure P0 in the valve chamber 21 is a graph showing the relationship between the negative pressure P0 in the valve chamber and the time t in FIG. 3 (for example, the internal combustion engine 11
When the rotation speed is 3000 rpm), the pulsating pressure is as shown. Therefore, when the pulsating pressure of the valve chamber 21 is small, the valve body 45 is pressed against the wall surface of the main body case 36 by the urging force of the spring 44 of the pulsating pressure damping valve 4, but when the pulsating pressure becomes large, negative pressure is applied. As shown in FIG. 1, due to the fluctuation of
Displaces left and right. The valve element 45 not only simply moves to the left and right in accordance with the fluctuation of the negative pressure P0, but also transmits the negative pressure to the hole 47 in the adjusting screw 46 in a state where the pulsation is attenuated.

Therefore, the negative pressure P1 in the negative pressure chamber 31 is almost zero because the negative pulsating pressure is attenuated as shown in the graph of FIG. 4 showing the relationship between the negative pressure P1 of the negative pressure chamber and the time t. It is close to pressure. When the filter element 13a of the air cleaner 13 is clogged and the negative pressure in the intake pipe 14 increases, the negative pressure is transmitted to the negative pressure chamber 31 of the clogging detection device 1. And
When the negative pressure P1 in the negative pressure chamber 31 reaches a value corresponding to the clogging limit of the filtration element 13a, the atmosphere 32 contains the atmosphere, so that the diaphragm 32 overcomes the biasing force of the spring 34. It moves in the direction of approaching the intake pipe 14. Due to the movement of the diaphragm 32, the contact 35a of the power supply side connection fitting 35c of the operation switch 35 connected to the operation rod 32a is connected to the contact 35d of the lamp side connection fitting 35f. For this reason, the power supply side connection fitting 35c and the lamp side connection fitting 35f are electrically connected, and the operation switch 35 is turned on.
Is lit, and the filter element 13 of the air cleaner 13
Make the clogging of a recognized. Therefore, the clogging detection device 1
Since the pulsation pressure damping valve 4 attenuates the pulsation pressure to approximate the static pressure, the pulsation pressure does not cause a malfunction before reaching the limit value of the clogging of the filtering element 13a, and an accurate air cleaner 13 is provided. Filter element 13a can be used to determine when it is time to replace or clean it, and it is still usable
The uneconomical point of exchanging 13a can be eliminated.

FIG. 5 shows a second embodiment of a clogging detecting device for an air cleaner of an internal combustion engine according to the present invention.

(The same functions as those in the first embodiment are designated by the same reference numerals.) In this embodiment, the atmospheric chamber 37 of the negative pressure servo 3 of the first embodiment is used.
As the second negative pressure chamber 37a, and a nozzle 52 that connects the valve chamber 51 and the cool air dout 17 (shown in FIG. 2), which is the intake pipe upstream of the air cleaner 13, is formed. A housing 5 having a connecting portion 53 that is screw-connected to the housing 5 and a pulsation pressure damping valve 6 provided in the housing 5 are provided.

The pulsation pressure damping valve 6 is provided between the valve chamber 51 of the housing 5 and the second negative pressure chamber 37a of the negative pressure servo 3 via a negative pressure pipe 51a, and the valve chamber 51 of the housing 5 and the negative pressure servo 3 are provided. Is formed on the valve body 63, which is biased by the spring 62 in the direction in which the second negative pressure chamber 37a does not communicate, the adjusting screw 64 fastened in the valve chamber 51 of the housing 5, and the adjusting screw 64, Housing 5
Of the valve chamber 51 and the second negative pressure chamber 37a of the negative pressure servo 3 communicate with each other.

The operation switch 30 of the present embodiment is provided with a power supply side connecting fitting 30c having a contact 30a at the tip and a power supply side terminal 30b having the other end connected to the battery 15, and a predetermined interval with the power supply side connecting fitting 30c. A lamp-side continuous metal fitting 30f provided with a contact 30d at the tip and a lamp-side terminal 30e connected to the clogging warning lamp 16 at the other end, a diaphragm 32, and a retainer 3
It is fixed to 4a, power supply side connection fitting 30c and lamp side connection fitting 3
It consists of a bowl-shaped connecting fitting 30g that is intermittent with 0f.

The negative pressure of the negative pressure chamber 31 increases, and the connecting fitting 30g overcomes the urging force of the spring 34, which falls below a predetermined negative pressure, and moves a predetermined distance in the direction in which the diaphragm 32 approaches the intake pipe 14 (right direction in the drawing). Therefore, move it to the right in the figure along with the diaphragm 32, and connect the power supply side fitting 30c and the lamp side fitting 30f.
And connect. When the negative pressure of the negative pressure chamber 31 is higher than a predetermined negative pressure, the diaphragm 32 of the connecting fitting 30g is separated from the power supply side connecting fitting 30c and the lamp side connecting fitting 30f by the urging force of the spring 34 as illustrated. Inside the body case 36,
A hole 36a that communicates between the valve chamber 21 and the negative pressure chamber 31 is formed.

Here, reference numerals 48 and 66 denote seal members attached to the valve bodies 45 and 63 in order to improve the sealing performance between the valve bodies 45 and 63 and the adjusting screws 46 and 64.

As in the present embodiment, the housing 5 and the pulsation pressure damping valve 6 are added to the first embodiment, and negative pressure is taken out from the upstream and downstream of the air cleaner 13, and left and right of the diaphragm 32 (the negative pressure chamber 31 and the second pressure chamber 31). In the differential pressure type clogging detection device 1 for transmitting the differential pressure to the negative pressure chamber 37a), the pulsating pressure between the upstream and downstream of the air cleaner 13 is smoothed, and the diaphragm 32 operates by the differential pressure. The clogging state of the filter element 13a of the air cleaner 13 can be detected more accurately than in the first embodiment.

6 to 8 show another example of the damping valve structure used in the clogging detection device of FIG.

(Functions which have the same functions as those in the first embodiment are designated by the same reference numerals.) The pulsation pressure damping valve 7 in the example of FIGS. 6 to 8 has a reed valve 71 because of the structure of the valve body and the spring in the first embodiment. , 7
The structure is 2, 73, and the length is shortened to reduce the size. The reed valves 71 and 72 are made of an elastic material such as rubber and have an umbrella shape, and the fixing portions 71a and 72a at the tips (lower ends in the drawing) have holes.
It is fixed to the adjusting screw 74 which forms 74a. The adjusting screw 74 is mounted in place of the adjusting screw 46 shown in FIG. On the other hand, the reed valve 73 shown in FIG. 8 is made of an elastic body such as a leaf spring, and has one end 73a fixed to the main body case 36 by a fixture 75 and the other end 73b being a free end.

In both cases, when negative pressure is transmitted to the valve chamber 21, the reed valves 71, 72,
73 is displaced in the direction of approaching the intake pipe 14, and from the valve plate 21 to the negative pressure chamber.
Negative pressure is transmitted to 31.

9 and 10 show a second embodiment of the clogging detection device for the air cleaner of the internal combustion engine according to the present invention.

(Functions that are the same as in the first embodiment are given the same numbers) In this embodiment, the intake pipe connecting portion 36b that connects to the intake pipe 14
A cylindrical housing 5a and a pulsation pressure damping valve 8 are built in a main body case 36 of the pressure servo 3 having the above. The housing 5a has a case chamber 55 that has a valve chamber 54 inside and is connected to the main body case 36, and a negative pressure chamber side portion 56 provided on the negative pressure chamber 31 side from the case connection portion 55. A nozzle 57 that connects the chamber 54 and the negative pressure chamber 31 is formed.

The pulsation pressure damping valve 8 includes a valve body 82 which is biased by a spring 81 in a direction (right direction in the drawing) in which the valve chamber 54 of the housing 5a and the negative pressure chamber 32 of the negative pressure servo 3 do not communicate with each other, and the main body case 36. The adjusting screw 83 is fastened in the hole 36a, and the hole 84 is formed in the adjusting screw 83.

Here, a spring-made thin plate contact point 35h connected to the contact point 35d of the lamp side connection fitting 35f is attached to the tip end portion 35g of the power supply side connection fitting 35c of the operation switch 35. When the diaphragm 32 moves and the rod 32a moves, the contact 35h is pressed and connected to the contact 35h by a spring force.

By incorporating the pulsation pressure damping valve 8 in the negative pressure servo 3 as in the present embodiment, the volume of the negative pressure chamber 31 can be reduced and the valve chamber
When the pressure P2 of 54 becomes larger than the pressure P1 of the negative pressure chamber 31,
Assuming that the leakage of the pulsation pressure damping valve 8 is the same as that of the external type of the first embodiment, the time until P1 = P2 becomes the ON / OFF state of the operation switch 35 in FIG. 10 and the static pressure. As shown in the graph showing the relationship, the external pulsation pressure damping valve (broken line) as in the first embodiment
From b, a built-in pulsation pressure damping valve (solid line) as in this embodiment a
Is faster. Therefore, in the present embodiment in which the pulsation pressure damping valve 8 is built in, the hysteresis becomes smaller and the responsiveness of clogging detection becomes better.

FIG. 11 shows a third embodiment of the clogging detection device for an air cleaner of an internal combustion engine according to the present invention.

(Functions that are the same as those in the first and second embodiments are given the same numbers.) In the third embodiment, the valve element 91 of the pulsation pressure damping valve 9 and the adjusting screw
In order to improve the sealing property with the wall surface of the intake pipe 14 side of the 92, a concave housing having a wall surface and a hole 93 having an end surface shape similar to the end surface shape of the wall surface of the valve body 91 on the negative pressure servo 3 side. 94 is provided between the valve body 91 and the adjusting screw 92.

Here, 95 is a spring for urging the valve body 91 in a direction in which the valve chamber 21 of the housing 2 and the negative pressure chamber 31 of the negative pressure servo 3 do not communicate with each other, and 96 is formed on the adjustment screw 92 and the housing 2
2 shows a hole that connects the valve chamber 21 and the negative pressure chamber 31 of the negative pressure servo 3.

FIG. 12 shows a fourth embodiment of the clogging detection device for the air cleaner of the internal combustion engine of the present invention.

(Functions having the same functions as those in the third embodiment are designated by the same numbers.) In the fourth embodiment, the valve body 97 of the pulsation pressure damping valve 9 and the adjusting screw.
In order to improve the sealing property of 92 with the wall surface on the side of the intake pipe 14 compared to the seventh embodiment, the valve body 97 is formed in a spherical shape, and the wall portion 27 with the hole 26 on the side of the intake pipe 14 of the housing 2 is a valve. It is formed in a curved shape corresponding to the shape of the body 97. As another embodiment, the wall portion 27 of the housing 2 may be omitted and the wall surface of the adjusting screw 92 on the intake pipe 14 side may be formed in a curved shape corresponding to the shape of the valve body 97.

FIG. 13 shows a fifth embodiment of a clogging detecting device for an air cleaner of an internal combustion engine of the present invention.

(Functions which have the same functions as in the fourth embodiment are given the same numbers.) In the fifth embodiment, the valve element 98 of the pulsation pressure damping valve 9 and the adjusting screw
In order to improve the sealing property of the wall surface of 92 on the intake pipe 14 side compared to the seventh embodiment, the valve body 98 is formed in a conical shape, and the wall surface of the adjusting screw 92 on the intake pipe 14 side has the shape of the valve body 91. Is shaped like a mortar. As another embodiment, the housing 2
It is also possible to eliminate the wall portion 27 and form the wall surface of the adjusting screw 92 on the intake pipe 14 side into a mortar shape corresponding to the shape of the valve body 98.

In this embodiment, the main body case of the negative pressure servo is connected to the housing, and the main body case or housing of the negative pressure servo is connected to the adjusting screw of the pulsation pressure damping valve by tightening. And so on.

In this embodiment, the pulsation pressure damping valve is adopted as the negative pressure pulsation damping means, but it may be narrowed down as the negative pressure pulsation damping means.

In the present embodiment, the operation switch is built in the negative pressure servo, but even if the operation switch is arranged outside the negative pressure servo by projecting the operation rod of the negative pressure servo to the outside of the negative pressure servo. good. In this case, the negative pressure servo is more compact than that in this embodiment.

In this embodiment, the clogging warning lamp is adopted as means for making the user recognize the clogging of the filter element of the air cleaner, but a clogging warning buzzer or the like is made as means for making the user recognize the clogging of the filtering element of the air cleaner. You may adopt it.

[Brief description of drawings]

FIG. 1 is a sectional view showing a first embodiment of a clogging detecting device for an air cleaner of an internal combustion engine according to the present invention, and FIG. 2 is a first embodiment of a clogging detecting device for an air cleaner of an internal combustion engine according to the present invention. FIG. 3 is a schematic view showing an intake system of the internal combustion engine, and FIG. 3 is a first view of a clogging detection device for an air cleaner of the internal combustion engine of the present invention.
The graph which shows the relationship between the negative pressure P0 of the valve chamber of Example, and time t,
FIG. 4 is a graph showing the relationship between the negative pressure P1 of the negative pressure chamber and the time t of the first embodiment of the clogging detection device for the air cleaner of the internal combustion engine of the present invention, and FIG. 5 is the air cleaner of the internal combustion engine of the present invention. Sectional view showing a second embodiment of the clogging detection device of FIG.
FIG. 7, FIG. 8 and FIG. 8 are sectional views showing other examples of the pulsation pressure damping valve in the first embodiment of the clogging detection device for the air cleaner of the internal combustion engine, and FIG. 9 is the internal combustion engine of the present invention. FIG. 10 is a cross-sectional view showing a second embodiment of the clogging detection device for an air cleaner of FIG. 10, and FIG. 10 is an ON / OFF state of an operation switch of the second embodiment of the clogging detection device for an air cleaner of an internal combustion engine of the present invention.
FIG. 11 is a cross-sectional view showing a third embodiment of a clogging detection device for an air cleaner for an internal combustion engine according to the present invention, and FIG. 12 is a graph showing a relationship between the state and static pressure. A sectional view showing a pulsation pressure damping valve of a fourth embodiment of a clogging detection device, and FIG. 13 is a sectional view showing a pulsation pressure damping valve of a fifth embodiment of a clogging detection device of an air cleaner of an internal combustion engine of the present invention. It is a figure. 1 in the figure: Clogging detection device 2, 5, 5a: Housing, 3
...... Negative pressure servo 4,6,7,8,9 pulsation pressure damping valve (damping means), 13 air cleaner, 13a filter element, 14 intake pipe, 21 valve chamber, 31 ...... Negative pressure chamber

Claims (1)

(57) [Claims] 1. A negative pressure chamber communicating with an intake passage downstream of a filter element of an air cleaner for supplying clean air to an internal combustion engine, when the negative pressure in the negative pressure chamber exceeds a predetermined negative pressure. A clogging detection device for detecting clogging of the filtration element, wherein clogging of an air cleaner of an internal combustion engine is provided, wherein damping means for negative pressure pulsation is provided between the intake passage and the negative pressure chamber. Detection device.