JP2000045953A - Negative pressure generating system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To generate negative pressure easily and cost-effectively without using part of motive power of the engine or the like. SOLUTION: A housing 1 that is divided into a first compartment 5 and a second compartment 6 incorporates a nonlinear vibration system composed of a block member 10 and spring members 19, 20 that act on the both sides of the block member 10. The vibration system forcibly vibrates with vibrations as external force which are generated during machinery 33 fixed to the housing 1 is in operation. The block member 10 is reciprocated by forcible vibrations to expand and reduce the first compartment 5. Resultant pumping action alternatingly opens/closes check valves 21, 22. Accordingly, air in a negative pressure storage tank 27 is discharged to generate negative pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for generating a negative pressure by using vibration of machinery, particularly vibration generated during operation of an engine as a power source.

[0002]

2. Description of the Related Art In a control system of an automobile engine, many actuators for controlling ignition timing, fuel pressure, idle speed, EGR, intake throttle valve and the like are operated by negative pressure in many cases.

[0003] As a negative pressure for operating the actuator, it is common to use a negative pressure generated in the intake pipe of an engine having a throttle valve for output control in the intake pipe of the engine. However, in the case where fuel is directly injected into the cylinder and the throttle valve for output control is not provided, almost no negative pressure is generated in the intake line. Alternatively, an electric motor such as a stepping motor that does not use negative pressure is used as an actuator.

On the other hand, regarding the fuel supply system of an automobile engine, it is predicted that the gasoline engine will be shifted to a system in which fuel is directly fed into a cylinder instead of an intake pipe, and negative pressure is applied to an intake pipe similarly to a diesel engine. Cannot be sought.

[0005]

Therefore, attention has been paid to a system in which a vacuum pump is driven by an engine to generate a negative pressure for operating an actuator. However, since the negative pressure constantly acts on the engine, fuel economy and mechanical efficiency are reduced. It is inevitable that it will worsen.

Further, when an electric motor is used as an actuator, the weight is not negligible depending on the number of actuators used, which adversely affects fuel economy and inevitably results in a disadvantage in price.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of a method of generating a negative pressure by driving a vacuum pump by a crankshaft of an engine and an electric motor as an actuator instead of the method. The purpose of the present invention is to provide a negative pressure generating device which does not deteriorate efficiency and is not disadvantageous in cost.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a negative pressure generating device according to the present invention comprises a first chamber having an air inlet connected to a negative pressure operating device and a second chamber having an open air. The block member is reciprocally housed in the housing partitioned into the chamber and the first chamber is enlarged and reduced, and a spring member acting to restore the block member to the equilibrium position is acted on both sides, In addition, the air on the negative pressure operating device side is sucked when the first chamber is expanded by the two check valves, and is discharged to the atmosphere when the first chamber is reduced.

When the housing is fixed to a machine that generates vibration during operation, the nonlinear vibration system including the block member and the spring members on both sides of the block member is forcibly vibrated by the vibration accompanying the operation of the machine. The reciprocating movement of the first chamber expands and contracts and the pump action of sucking and discharging air is performed in a reciprocal manner, so that the negative pressure operating device side can be made negative pressure.

When the first chamber is connected to the negative pressure operation device via the negative pressure storage tank, the negative pressure is stored, and the negative pressure can be appropriately applied to the load operation device.

Further, in the case where the first chamber and the second chamber are partitioned by a flexible film and the block member is attached to the center of the flexible film and is guided along the guide, the block member may be vibrated by machinery. The reciprocating motion is smoothly performed in a stable posture.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the accompanying drawings. A cup-shaped first case 2 and a second case 3 are opposed to each other, and their peripheral wall edges are made of a diaphragm. The housing 1 is formed by sandwiching the periphery of the membrane 4 and tightening it. The interior of the first case 2 and the second case 3 is divided into a first chamber 5 and a second chamber 6 separated from each other by the flexible membrane 4. Has formed. A pipe-shaped air inlet 7 protruding outward at the center of the bottom wall of the first case 2.
Is provided, and a hole-shaped air outlet 8 is provided in the center of the bottom wall of the second case 3.

Retainers 9, 9 and first and second blocks 11, 12 are superposed on both sides of the flexible membrane 4, and are formed at the center of the second block 12, which is located inside the second chamber 6. A screw shaft piece 13 projects into the first chamber 5 and is screwed into the center of the first block 11. That is, the first block 11 and the second block 12 constitute a block member 10 fixed to the flexible film 4 with the retainers 9, 9 interposed therebetween, and a communication passage formed through the center of the second block 12. 14 communicates the first chamber 5 and the second chamber 6.

Cylindrical guides 15 and 16 are fixed to the inner surfaces of the bottom walls of the first case 2 and the second case 3, and both ends of the block member 10, that is, the first block 11 and the second block 12 are fixed to the guides 15. , 16 are fitted. The distal end portions of the first block 11 and the second block 12 are formed in an annular shape, and annular elastic stoppers 17, 18 in which the end surfaces of the annular portions 11a, 12a are balanced are mounted on the bottoms of the guides 15, 16. I have.

Between the guide 15 of the first chamber 5 and the first block 11 and between the guide 16 of the second chamber 6 and the second block 12, spring members 19 and 20 made of a compression coil spring are initially compressed. It is charged in a state. The first block 11 and the second block 12 of the first chamber 5 and the second chamber 6 and the guide 1
The inner space surrounded by the inner space 5 and the outer space and the outer space are the guides 15 and 16 and the annular portions 11a and 12a.
Communication is always provided by a ventilation portion such as a hole or notch provided in one or both of the above.

Further, an open end of the air inlet 7 to the first chamber 5;
The first check valve 2 is provided at the open end of the communication passage 14 to the second chamber 6.
First and second check valves 22 are provided. Known check valves 21 and 22 such as a ball valve, a butterfly valve, and a duckbill valve can be used. In the illustrated embodiment, the valve plate 23 made of a circular rubber plate is connected to the first case 2 and the first case 2. The gap 25 formed between the fixing portions 24 when the valve plate 23 swells and deforms toward the first chamber 5 and the second chamber 6 due to the pressure difference is fixed by an adhesive at a plurality of places on the two blocks 12. The air flowed through.

An air outlet 8 opens the second chamber 6 to the atmosphere, and an air inlet 7 connects the first chamber 5 to a negative pressure storage tank 27 via a pressure-resistant hose 26. The negative pressure storage tank 27 is connected to a negative pressure operating device 30 through a negative pressure conduit 29 provided with an electromagnetically driven opening / closing valve 28.
Connected to.

Further, the housing 1 is fixed to the machinery 33 by fixing a bracket 31 which is a fixing means fixed to the end surface thereof to a proper position on the surface of the machinery 33 which generates vibration during operation by bolts 32. You. The machinery 33 is an automobile engine in many cases, and the housing 1 is mounted on the machinery 33 so that the direction in which they generate the maximum frequency or amplitude is parallel to the central axes of the block members 10 and the spring members 19 and 20. It is desirable to consolidate in

The block member 10 and the initially compressed spring members 19 and 20 disposed on both sides of the block member 10 in the illustrated embodiment are non-linear vibration systems, and the vibration of the machinery 33 is transmitted through the bracket 31 and the housing 1. This causes forced vibration.

Here, in the case where the machinery 33 is operated at a substantially constant speed and generates substantially constant vibration, the vibration frequency and the machinery 33 are operated at various speeds like an engine and generate various vibrations. The weight of the block member 10 is set so that the difference between the frequency at the most frequently operated speed and the natural frequency of the vibration system is as small as possible, and ideally equal. It is preferable to select the spring force of the spring members 19 and 20 to make them. In this way, the vibration system to which the vibration of the machinery, which is an external force, is applied is amplified, and the block member 10 vibrates with a large amplitude and resonates in some cases.

When the block member 10 moves from the equilibrium position shown in FIG. 1 to the first chamber 5 as shown in FIG. At the same time as the volume of the second chamber 6 increases. Since the second chamber 6 is always at the atmospheric pressure, when the volume of the first chamber 5 becomes higher than the atmospheric pressure due to the volume reduction, the second check valve 22 opens to discharge air to the atmosphere. Block member 1
When 0 moves toward the second chamber 6 as shown in FIG. 3 (B), the volume of the first chamber 5 expands to reduce the pressure, and the first check valve 2
The valve 1 opens to suck the air in the negative pressure storage tank 27 into the first chamber 5.

As described above, the expansion and contraction of the first chamber 5 caused by the reciprocating movement of the block member 10 is repeated, so that the negative pressure storage tank 2 is formed.
The air of No. 7 is discharged, and a negative pressure is created. While the pumping operation is being performed, the first chamber 5 and the second chamber 6 are partitioned by the flexible membrane 4, so that there is no air leakage between them and the efficiency is not reduced, and
Since the block member 10 has both ends fitted in the guides 15 and 16, the block member 10 smoothly reciprocates while maintaining a stable posture,
In addition, since the flexible film 4 easily deforms following the block member 10, it does not hinder reciprocation due to vibration.
Further, when the amplitude of the block member 10 increases, the maximum stroke thereof is regulated by the elastic stoppers 17 and 18, and when a collision occurs, the impact is alleviated, so that no collision sound is generated and no damage is caused.

When the negative pressure of the negative pressure storage tank 27 becomes high, specifically, this negative pressure is equal to the negative pressure of the first chamber 5 at the time of the maximum volume, and the pressure of the first chamber 5 at the time of the minimum volume. When the atmospheric pressure is reached, the block member 1
Even if 0 reciprocates, the two check valves 21 and 22 remain closed, and a constant negative pressure is stored in the negative pressure storage tank 27. For this reason, even if there are a plurality of negative pressure operating devices 30 and negative pressure is applied to them at the same time, the devices can be appropriately applied. When the negative pressure in the negative pressure storage tank 27 decreases, the above-described pump action is restarted, and the machinery 33
Operates so as to store a constant negative pressure in the negative pressure storage tank 27 as long as is operated.

Therefore, even if the air inlet 7 is directly connected to the negative pressure operating device 30, the required negative pressure can be obtained during the operation of the machinery 33. However, as shown in the illustrated embodiment, the negative pressure storage tank 27 is provided.
Is installed, it is possible to apply a negative pressure to a plurality of negative pressure operating devices 30 at the same time or to apply a negative pressure when the machinery 33 is stopped.

The embodiment of the present invention includes forming the housing 1 in a cylindrical shape and forming the block member 10 in a piston or plunger shape and reciprocating in a sliding state. It is also an embodiment of the present invention that the second check valve 22 for discharging the air in the first chamber 5 to the atmosphere is provided at an appropriate position on the peripheral wall of the first case 2.

[0026]

As described above, the vibration generated by the operation of machinery is used as an external force to forcibly vibrate the vibration system composed of the block member and the spring member, and a negative pressure is generated by the reciprocating pumping action. According to the present invention, a negative pressure can be generated very simply and economically without using special power or consuming a part of the power.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention.

2 (A) is a longitudinal sectional view and FIG. 2 (B) is a front view illustrating a check valve in the embodiment of FIG.

FIGS. 3A and 3B are longitudinal sectional views for explaining the operation of the embodiment shown in FIG. 1;

[Explanation of symbols]

1 housing, 4 flexible membrane, 5 first chamber, 6
2nd chamber, 7 air inlet, 10 block member, 1
4 communication passage, 15, 16 guide, 17, 18 elastic stopper, 19, 20 spring member, 21 first check valve, 22 second check valve, 27 negative pressure storage tank, 31
bracket,

Claims (6)

[Claims] 1. A housing partitioned into a first chamber having an air inlet connected to a negative pressure operating device and a second chamber open to the atmosphere; and a housing reciprocally built in the housing to enlarge the first chamber. A block member that contracts, a spring member that acts on the block member from both sides to restore the equilibrium position, and opens when the first chamber is expanded to release air on the side of the negative pressure operating device. A first check valve for sucking into the chamber, a second check valve that opens when the first chamber is reduced and discharges air in the first chamber to the atmosphere, and a housing for generating vibration during operation. And a coupling means for consolidating the first chamber, and the block member is forcibly vibrated by the vibration of the machinery to repeatedly expand and contract the first chamber, thereby creating a negative pressure on the negative pressure operating device side. A negative pressure generator characterized by the above-mentioned. 2. The negative pressure generator according to claim 1, further comprising a negative pressure storage tank connected to the air inlet, wherein the negative pressure operating device is connected to the negative pressure storage tank. And a negative pressure generator. 3. The negative pressure generator according to claim 1, wherein the first chamber and the second chamber are partitioned by a flexible film,
The negative pressure generating device, wherein the block member is attached to a central portion of the flexible membrane and reciprocates linearly along a guide provided on the housing. 4. The communication device according to claim 1, wherein the block member has a communication passage communicating the first chamber and the second chamber, and the second check valve is provided in the communication passage. The described negative pressure generator. 5. The negative pressure generator according to claim 1, wherein the spring member acted on the block member from both sides is a coil spring that is initially compressed. 6. An elastic stopper for restricting a maximum stroke of reciprocation of the block member.
Or the negative pressure generator according to 3.