JPH0433135Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Field of Application> The present invention relates to an actuator for a constant speed traveling system for automobiles, and particularly to an actuator of the above type having an air filter structure that has been improved to withstand long-term use.

<Prior Art> Various constant speed traveling devices for maintaining the speed of a vehicle at a predetermined set speed have been known in the past.
According to such a constant speed traveling device, by operating the accelerator pedal and pressing the set button when the desired vehicle speed is reached, the vehicle speed can be maintained at the set speed even if the foot is released from the accelerator pedal. .

As a constant speed traveling device of this type, for example, a device in which a throttle valve is driven by an actuator using the engine's suction negative pressure as the operating source is known. According to this device, a negative pressure chamber defined by a housing and a diaphragm is used. By selectively operating a plurality of solenoid valves having ports communicating with the atmosphere and the intake manifold, respectively, the pressure within the negative pressure chamber is changed, and the displacement of the diaphragm is controlled via a wire connected to the diaphragm. , for example, to the accelerator pedal to obtain the desired throttle opening. Furthermore, the solenoid valve for atmospheric pressure communication includes a vent valve for eliminating negative pressure in the negative pressure chamber during normal operation of the constant speed traveling device;
Two electromagnetic valves are used in parallel, each consisting of a safety valve for backing up the vent valve and stopping the operation of the constant speed traveling device.

By the way, since the atmosphere inlet of the actuator as described above is directly connected to the atmosphere, an air filter is required to purify the atmosphere to be inhaled. This air filter is installed just before the inlet port of the solenoid valve, and is housed in an air filter holder that is provided to separate the two atmosphere communication solenoid valves from each other in order to prevent dust and moisture from entering. The outside will be covered with a cover. In other words, the air introduced through the air inlet, which is normally provided in the cover, is deflected in the cavity defined between the cover and the air filter holder and passes through the filter, causing dust and moisture to escape. Removal efficiency is improved and clogging of the air filter can be prevented.

<Problems to be Solved by the Invention> However, during long-term use or under severe use conditions, clogging of the filter cannot be avoided to some extent. If the filter becomes clogged, the ventilation resistance will change, which may even affect the operating characteristics of the actuator. In particular, the vent valve side, which requires a high response speed, is susceptible to clogging.

For this reason, to ensure reliability, air filters must be replaced frequently.
Maintenance and inspection tended to be complicated.

In view of these drawbacks of the prior art, the main purpose of the present invention is to provide an actuator for a constant speed vehicle for a vehicle that has an air filter structure that can prevent clogging for a long period of time.

<Means for Solving the Problems> According to the present invention, such an objective is to provide a negative pressure chamber defined by a housing and a diaphragm;
a negative pressure solenoid valve and a plurality of atmospheric solenoid valves having one end communicating with the negative pressure chamber and connected and fixed to each other in parallel; a cover covering the other end side of the atmospheric solenoid valve;
an air filter holder sandwiched between the cover and the other end side of the atmospheric solenoid valve; and an atmospheric air inlet provided in the cover at a position offset from the inlet opening of the air filter holder. an actuator for a constant speed traveling device for an automobile, wherein the flow path area of an air inflow path from the air inlet to the air filter received in the air filter holder is different for the plurality of air solenoid valves. This is achieved by providing an actuator for a constant speed vehicle for an automobile, which is characterized by the following.

<Function> In this way, among the multiple solenoid valves that introduce atmospheric air, if the inlet area of the vent valve side is made particularly small, when the safety valves are simultaneously communicated with the atmosphere, such as when canceling constant speed driving, the safety valves On the other hand, a larger amount of atmospheric air is introduced toward the negative pressure chamber, and contamination of the air filter on the vent valve side can be minimized.

<Embodiments> The present invention will now be described in detail with reference to specific embodiments with reference to the accompanying drawings.

FIG. 1 is an explanatory diagram schematically showing a constant speed traveling device to which an actuator unit based on the present invention is applied.

The actuator unit consists of a ventilation control section 1 and a diaphragm section 2, and the ventilation control section 1 includes:
Three electromagnetic valves consisting of a vacuum valve 3, a safety valve 4, and a vent valve 5 are provided.

Inside the housing 6 of the diaphragm part 2,
A diaphragm 8 biased in one direction by a coil spring 7 is provided, and a negative pressure chamber 9 defined by the diaphragm 8 communicates with one port of the three electromagnetic valves. A wire holder 10 is fixed to the center of the surface of the diaphragm 8 on the side opposite to the negative pressure chamber 9, and the wire holder 10 moves in the axial direction depending on the magnitude of the negative pressure in the negative pressure chamber 9, for example. Fuel supply to the engine is controlled by driving an accelerator pedal (not shown) connected by a wire.

The other port of the vacuum valve 3 is connected to the pipe line 1
1 and a check valve 12 to an engine suction pipe (not shown), and by opening the vacuum valve 3, the negative pressure in the negative pressure chamber 9 is increased, and the diaphragm 8 is pulled in the retracting direction. The motion can drive the accelerator pedal in a direction that increases vehicle speed. Incidentally, an accumulator 13 connected to the pipe line 11 functions to store negative pressure to be introduced into the negative pressure chamber 9.

The other port of the vent valve 5 communicates with the atmosphere via the air filter unit 14, and by opening the vent valve, the atmosphere is introduced, reducing the negative pressure in the negative pressure chamber 9, and extruding the diaphragm 8. Movement in the direction can drive the accelerator pedal in a direction that reduces vehicle speed.

The safety valve 4, like the vent valve 5, communicates with the atmosphere via the air filter unit 14, and can cancel the operation of the constant speed traveling device.
Alternatively, it opens when some kind of abnormality is detected and the function of the constant speed traveling device is stopped, and similarly functions to communicate the negative pressure chamber 9 with the atmosphere.

These valves 3 to 5 are controlled by signals from a control circuit 15 so as to obtain an appropriate vehicle speed.

FIG. 2 shows the ventilation control section 1 of the actuator unit described above in detail.

A box-shaped valve case 20 with one end open
is integrally molded with the housing 6 of the negative pressure chamber of the actuator unit from synthetic resin. An inward step 21 is provided around the entire circumference inside the valve case 20 near the open end thereof, and is adapted to support a gasket 22 as a sealing material. Further, four tap holes 23 are cut at diagonal positions outside the inward step 21 on the opening end surface of the valve case 20.

The bottom of the valve case 20 is provided with a through hole 24 that can tightly receive an outlet port of a solenoid valve to be described later, and these outlet ports are connected to a passage 25 formed to protrude outward from the bottom of the valve case 20. It communicates with the negative pressure chamber 9 via.

The three solenoid valves 3 to 5 are each fixed to a common plate 26 by caulking to form one solenoid valve assembly, and the power supply terminals of these solenoid valves are connected to the lead wires collected on the printed circuit board 27. 28 so that it can be led out to the outside. The outlet ports 29 of these electromagnetic valves are fitted into the through holes 24 at the bottom of the valve case 20 via O-rings 30.

An end cover 31 that seals the opening of the valve case 20 has a through hole 32 through which a negative pressure port 3a protrudingly provided on the vacuum valve 3 can be inserted, and an air filter housing expansion provided outwardly protruding at the center thereof. Screw holes 36 corresponding to the tap holes 23 of the valve case 20 described above are penetrated at diagonal positions at four corners of a flange portion 35 on the outer periphery. An outward step portion 37 corresponding to the inward step portion 21 of the valve case 20 is formed on the inner and outer peripheral portion of the end cover 31, and the gasket 22 is sandwiched between these steps, and the valve case 20
It is designed to ensure internal airtightness.

The air filter storage bulge 34 is formed in the shape of an oblong recess that bulges outward from the outer surface of the end cover 31, and receives the two air filters 38 therein and the air filter holder 39 therein. The inner periphery of the air filter holder contacts the periphery of the opposite end surface of the air filter holder 39 via the gasket 40, and only the air introduction port 33, the safety valve 4, and the inlet port 41 of the vent valve 5 communicate with the inside of the air filter holder. It is classified as a sealed vacant room.

Furthermore, plate 2 of the solenoid valve assembly described above
6 to the inner surface of the end cover 31 using screws 42, the end cover 31 and the solenoid valve assembly are integrally fixed with the air filter holder 39 sandwiched therebetween.

The air filter holder 39 made of polypropylene resin has two shallow cylindrical parts 43 in which the sponge-like air filter 38 is received.
A boss 46 having an inner hole 45 that fits through an O-ring 44 is provided to protrude outward.

The two shallow-bottomed cylindrical parts 43 of the air filter holder 39 are connected by a common bottom wall and a peripheral wall to form an integrally molded container shape, and the outer periphery of the bottom wall of one of the cylindrical parts has a through-hole. The air hole 43a is drilled (Fig. 3), and this is because ventilation inside the solenoid valve casing is carried out through an air filter to prevent salt mist or water droplets from directly entering the solenoid valve. This is to improve the durability of the valve.

An axial protrusion 47 as a baffle plate is formed in adjacent portions of these two cylindrical parts 43, and one protrusion has an extension as an extension of the baffle plate extending along the circumferential direction. A portion 48 is formed, and the side having this extension portion 48 is the vent valve 5.
It has a corresponding side.

When the tips of the protrusions 47 and the extensions 48 collide with the inner surface of the air filter storage bulge 34, the air filter storage bulge 34
A void is formed within the chamber into which air flows. The inlet ports 41 of the solenoid valves 4 and 5 and the inner hole 45 on the inner surface of the air filter holder 39 are sealed by an O-ring 44, and the negative pressure port 3a and the through hole 32 are sealed by a bushing 49.

In this way, the ventilation control section 1 is completed by fixing the solenoid valve assembly and the end cover 31 to which the air filter is attached to the casing 20 using the screws 50. When the actuator unit assembled in this way is actually installed in a vehicle, if the atmosphere introduction port 33 is arranged downward, it is possible to more effectively prevent the infiltration of dust and water droplets due to the action of gravity. .

Next, the operation of the present invention will be explained.

As clearly shown in FIGS. 3 and 4, the airflow flowing in from the air introduction port 33 is directed to the central lower bottom 39a of the oval air filter holder 39.
After colliding with , it flows into the air filter 38 , but first collides with the central lower bottom 39 a to reduce the flow velocity, and relatively large mass of dust is separated. Furthermore, the peripheral wall-shaped protrusion 47 of the cylindrical portion 43 acts as a baffle plate, and the air flow to the air filter 38 becomes turbulent, which prevents even minute dust from penetrating deep into the filter, thereby preventing clogging. can be effectively prevented.

When both the vent valve 5 and the safety valve 4 solenoid valves are opened at the same time, the flow path area on the vent valve side is narrowed by the extension part 48 arranged on the vent valve side, so more air flows into the safety valve side. will flow in. This reduces the burden of dust collection on the air filter on the vent valve side, which is constantly activated during constant speed driving control.

<Effects of the invention> As described above, according to the invention, it is possible to make the air filter less likely to be clogged, and it is possible to reduce the burden of dust collection on the vent valve side, which requires particularly responsiveness, so that it can be used for a long period of time. This has a great effect on maintaining reliability at a high level throughout the process.

[Brief explanation of the drawing]

FIG. 1 is an explanatory view schematically showing the entire actuator unit of a constant speed traveling device. FIG. 2 is an enlarged perspective view, partially cut away, of essential parts based on the present invention. FIGS. 3 and 4 are explanatory diagrams showing the air flow to the air filter. 1... Ventilation control section, 2... Diaphragm section, 3
... Vacuum valve, 3a ... Negative pressure port, 4
...Safety valve, 5...Vent valve, 6...
... Housing, 7 ... Coil spring, 8 ... Diaphragm, 9 ... Negative pressure chamber, 10 ... Wire holder,
11...Pipe line, 12...Check valve, 13...
...Accumulator, 14...Air filter unit, 15...Control circuit, 20...Valve case,
21... Inward step, 22... Gasket, 23
...Tap hole, 24...Through hole, 25...Passway, 2
6...Plate, 27...Printed circuit board, 28...
... Lead wire, 29 ... Outlet port, 30 ... O ring, 31 ... End cover, 32 ... Through hole, 3
3...Air introduction port, 34...Air filter storage bulge, 35...Flange, 36...Screw hole, 37...Outward step, 38...Air filter, 39...Air filter holder, 39a... ...Central bottom, 40... Gasket, 41... Inlet port, 42... Screw, 43... Cylindrical part, 44...
O-ring, 45...inner hole, 46...boss, 47...
...Axis direction protrusion, 48... Extension part, 49... Bushing, 50... Screw.

Claims (1)

[Claims for Utility Model Registration] (1) A negative pressure chamber defined by a housing and a diaphragm, and a plurality of negative pressure solenoid valves having one end communicating with the negative pressure chamber and connected and fixed in parallel to each other. an atmospheric solenoid valve, a cover covering the other end of the atmospheric solenoid valve, an air filter holder sandwiched between the cover and the other end of the atmospheric solenoid valve, and an inlet opening of the air filter holder. An actuator for a constant speed traveling system for a motor vehicle, the actuator having an atmosphere inlet provided in the cover at a position offset from the air intake, wherein the air flows from the atmosphere inlet to an air filter received in the air filter holder. An actuator for a constant speed vehicle for an automobile, characterized in that the flow path area of the inflow path is different for the plurality of atmospheric solenoid valves. (2) A baffle plate that detours the flow of air from the air inlet to the air filter is integrally provided in the air filter holder, and the baffle plate has a size that is equal to or larger than the plurality of solenoid valves described above. 2. An actuator for a constant speed traveling device for an automobile according to claim 1, wherein the actuator has a flow path area that is different by having different flow path areas.