JPH10131900A - Pumping device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide constitution that can maintain an increase in intake quantity obtained by heightening vacuum suction force without increasing the cost of a device for preventing the decrease of intake quantity even in the case of heightening vacuum suction force. SOLUTION: A pumping device 10 is provided with an internal combustion engine 11, a compressor 12 driven by the internal combustion engine 11, an ejector 13 for generating vacuum suction force with discharge air from the compressor as a blowout source. An atmosphere intake part 20 that can be communicated with the atmosphere is provided in an intake passage 17 for leading air, sucked by the ejector 13, into the compressor 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pump device, and more particularly, to a vacuum device using an internal combustion engine, a compressor driven by the internal combustion engine, and an ejector for generating a vacuum suction force by exhalation from the compressor. It relates to an intake structure with an increasing structure.

[0002]

2. Description of the Related Art Pump devices have various uses, one of which is a lining work inside an underground pipe and a soil excavation work on the ground. The lining work inside the pipe of the buried pipe is the work to form a coating film on the inner surface of the pipe,
The following are examples. In other words, by applying a negative pressure from one end in the extension direction of the pipe, an air flow in the pipe is generated from the other end in the extension direction to one end, and the coating nozzle of the lining coating pig that is introduced into the pipe and is movable is inserted into the pipe. The lining resin liquid is centrifugally applied by being rotated by an air flow. In addition, there is a case where the pig for cleaning the inside of the pipe or the parachute is moved in the inside of the pipe by utilizing the generation of the air flow in the pipe.

[0003] For excavating soil on the ground, a crusher having a crushing blade rotatably driven by an air motor is provided at a tip of a handle that can be gripped by an operator, and the crushing blade is rotated by compressed air to crush the soil. In addition, the crushed soil is suctioned and removed by a vacuum hose connected to a vacuum suction device. The crusher and the vacuum suction device used for the soil excavation work are often used at the same time, and therefore, the compressed air generated by the compressor and the vacuum suction force are used. The above-mentioned vacuum suction force is used when moving the pig for lining application used for lining work in a pipe to generate an air flow in the pipe when rotating the coating nozzle.

As a structure for obtaining a vacuum suction force, for example, there is a structure shown in FIG. In FIG. 6, an air discharge passage 2 of the compressor 1 and an intake passage 3 of the compressor 1 are connected to an injector 4. Ejector 4
Is the air discharge path 2 of the compressor 1 as shown in FIG.
Nozzle 4 for injecting compressed air discharged from
A and a diffuser 4B which generates a vacuum suction force by the compressed air. The compressed air has a high pressure and is supplied from the compressor 1 to generate a negative pressure in the diffuser 4B. As a result, a vacuum suction force is generated, and air can be taken in from the opening 4C formed in a part thereof and communicating with the atmosphere. The air taken in by the eductor 4 is introduced into the compressor 1 through the intake passage 3 communicating with the intake part of the compressor 1, and is suctioned by applying the vacuum suction generated by the compressor 4 together with the vacuum suction generated by the compressor 1. The intake amount is increased by the force.

[0005]

In the above-described pump device, the compressed air of the compressor 1 is supplied to the eductor 4 and the vacuum suction force in the eductor 4 is applied. The vacuum suction force can be increased as compared with the case of (1). However, when the compressed air from the compressor 1 is supplied to the eductor 4 to increase the vacuum suction force by the eductor 4, the compressor 1
The amount of intake air when the own vacuum suction force is used decreases, and when a negative pressure obtained by a certain vacuum suction force is reached, suction is stopped. For this reason, when the intake air amount using the vacuum suction force of the compressor 1 decreases, the pump efficiency in the compressor 1 decreases, and it may be expected that the vacuum suction force by the ejector 4 using the compressed air from the compressor 1 increases. There is a problem that can not be. Therefore, in order to solve such a problem, it is conceivable to arrange a switching valve for switching the intake path in the intake path of the compressor 1. The expansion may increase the cost of the apparatus. In addition, when a switching valve is installed, leakage of air flowing through the intake passage occurs unless the sealing characteristics at the installation portion are strict, and the amount of air required for the compressor can be secured. There is a possibility that it will not be possible.

SUMMARY OF THE INVENTION In view of the above-mentioned problems in the conventional pump device, the object of the present invention is to increase the vacuum suction force without increasing the cost of the device for preventing a decrease in the intake air amount even when the vacuum suction force is increased. An object of the present invention is to provide a pump device having a configuration capable of maintaining an increase in the intake air amount due to the increase.

In order to achieve this object, an invention according to claim 1 includes an internal combustion engine, a compressor driven by the internal combustion engine, and an ejector that generates a vacuum suction force by using exhaust gas from the compressor as an ejection source. A pump device provided with an air intake section that can communicate with the atmosphere in an intake path for introducing the air sucked by the above-described injector into the compressor.

According to a second aspect of the present invention, in the pump apparatus according to the first aspect, the atmosphere intake portion is constituted by a small-diameter atmosphere inlet.

According to a third aspect of the present invention, in the pump device according to the second aspect, the air intake section closes the opening by a predetermined pilot pressure, and the pressure of the suction section of the compressor reaches a predetermined value or less. An opening / closing member that opens the opening at a point in time is provided.

According to a fourth aspect of the present invention, there is provided a pump device comprising an internal combustion engine, a compressor driven by the internal combustion engine, and an ejector for generating a vacuum suction force by using the air discharged from the compressor as an ejection source. When an air intake portion is provided in the intake passage for introducing air sucked by the above-described eductor into the compressor, the air intake portion can communicate with the atmosphere, and the pressure in the intake passage corresponds to a pressure at which the amount of intake air in the compressor decreases. And a control valve that is set to a state in which the atmosphere can be introduced from the atmosphere intake section.

[0011]

According to the first aspect of the present invention, by providing an air intake portion that can communicate with the atmosphere in the intake passage closer to the intake portion of the compressor than the connection portion with the ejector, the air is sucked by the vacuum suction force of the ejector. Since the atmosphere can be taken into the flow path through which the air flows, the air can be replenished from the atmosphere intake section to the suction section of the compressor even if the intake amount due to the vacuum suction force of the compressor decreases.

According to the second aspect of the present invention, since air can be taken into the intake portion of the compressor simply by forming a small-diameter air inlet, a reduction in the intake air amount of the compressor can be prevented with a simple structure. can do.

According to the third aspect of the present invention, a special on-off valve that can set the on-off valve that closes the air intake portion by the pilot pressure in an open state in accordance with a change in the pressure of the intake portion of the compressor is used. With a simple structure without requiring a pressure detection structure, it is possible to prevent a reduction in the amount of intake air to the compressor.

According to the fourth aspect of the invention, when the pressure in the intake passage corresponds to the pressure at which the amount of intake air in the compressor decreases, the atmosphere is forcibly introduced to replenish the amount of intake air in the compressor.

[0015]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. FIG. 1 is a schematic diagram for explaining a main configuration of a pump device according to the present invention, and FIG. 1 shows an intake system in the pump device. In FIG. 1, a pump device 10 includes an engine 11 as an internal combustion engine and a compressor 12 driven by the engine 11,
Further, an compressor 13 is connected to the compressor 12. The engine 11 is connected to the compressor 12 by a coupling 14 provided on an output shaft. As the engine 2, a diesel engine which is relatively resistant to intake and exhaust pressure fluctuations is used.

The compressor 12 is of a reciprocating type or a screw type in order to generate a vacuum suction force by intake air and also to generate high-pressure air by exhalation. The compressor 12 uses a supply of exhalation air to an ejector 13 described later and high-pressure air. Supply working pressure gas to the work machine. As a work machine using high-pressure air, there is an air motor for rotating a crushing blade for soil excavation described in the related art. Although the details of the ejector 13 are not shown, for example, as shown in FIG. 7, an ejection nozzle (corresponding to a member indicated by reference numeral 4A in FIG. 7) and a diffuser (reference numeral 4B in FIG. And an opening communicating with the air discharge portion of the diffuser (in FIG. 7,
(Corresponding to a portion indicated by reference numeral 4C). The vacuum suction force generated by the ejector 13 is used, for example, in a crushed soil suction device used in the above-described soil excavation work, or the air flow in the pipe due to the generation of a negative pressure in the pipe described in the related art. Used for generation.

An air discharge passage 15 communicating with the injection nozzle of the ejector 13 is connected to an air discharge portion of the compressor 12, and an air discharge passage of the compressor 13 is connected to an air discharge side of the ejector 13 via an air cleaner 16 to an intake portion of the compressor 12. The intake path 17 is connected. In the figure, the arrow is
The direction in which air flows is shown.

An air intake section 20 is provided near the intake section of the compressor 12 in the intake path 17 so as to communicate with the atmosphere. The air intake section 20 is constituted by an air inlet formed of a small-diameter opening formed in the intake passage 17, and has an internal pressure in the intake passage 17, that is, a pressure generated by air discharged from the injector 13 and flowing through the intake passage 17. The air outside the intake path 17 can be sucked by the pressure difference between the intake path 17 and the outside of the intake path 17.

In the present embodiment, the compressor 12 is driven by the engine 11 because of the above-described configuration.
The air sucked from 7 is compressed and discharged to the ejector 13 as high-pressure air. In the ejector 13, an injection nozzle (corresponding to the member indicated by reference numeral 4A in FIG. 7)
When a high-speed air flow is discharged from the nozzle, a vacuum suction force is generated, and an opening (corresponding to a portion indicated by reference numeral 4C in FIG. 7) communicating with the diffuser (a member corresponding to reference numeral 4B in FIG. 7) is connected to the outside. Air is sucked. The air sucked by the ejector 13 flows from the air discharge side to the intake passage 17.
And flows into the intake section of the compressor 12. As a result, the suction air amount can be increased by using the vacuum suction force of the ejector 13 in addition to the suction force of the compressor 12.

On the other hand, if the vacuum suction force is increased by using the ejector 13, the air intake amount of the compressor 12 decreases when the suction pressure of the air in the ejector 13 reaches a certain pressure. Therefore, the effect of increasing the suction force by using the compressor 12 cannot be obtained. Therefore, in the present embodiment, a reduction in the amount of intake air in the compressor 12 is suppressed by forcibly taking in the atmosphere into the intake passage 17 by the vacuum suction force obtained in the injector 13. That is, when the amount of air flowing through the intake passage 17 reaches an amount corresponding to the upper limit value (minimum vacuum pressure) of the suction pressure in the injector 13, the flow rate of the air obtained by the pressure causes the vicinity of the air intake portion 20 of the intake passage 17. , The tendency to negative pressure increases. For this reason, when the pressure difference between the atmosphere intake section 20 and the outside increases, external air is introduced into the intake path 17 via the atmosphere intake section 20.
When air from the outside is introduced into the intake passage 17, the air from the outside is replenished to the intake portion side of the compressor 12.

FIG. 2 is a graph showing the relationship between the negative pressure (horizontal axis) and the amount of suction air (vertical axis) obtained in the above embodiment.
In the figure, the result indicated by reference sign A is a case of the conventional structure having no air intake part, and the result indicated by reference sign B is:
In the case of the structure using the switching valve described in the conventional example,
The result indicated by reference numeral C is for the structure of the present embodiment. As is clear from FIG. 2, in the case of the structure having no atmosphere intake section 20 (result indicated by reference character A), when the negative pressure value reaches a certain value, the intake air amount cannot be obtained. Further, in the case of the structure having the switching valve (result indicated by the symbol B), the intake air amount is ensured even if the negative pressure tendency is increased. Costs are higher.
On the other hand, in the case of the structure of the present embodiment (result indicated by reference character C), as in the case of the structure having the switching valve, even if the negative pressure tendency increases, the intake air amount cannot be obtained, The air amount necessary for the operation of the pump at 12 can be secured.

As described above, according to the present embodiment, the air can be automatically replenished to the compressor 12 in accordance with the change in the pressure of the suction air from the ejector 13, so that the vacuum suction force of the To prevent the compressor 12 from deficient in the intake air amount due to the increase in
It is possible to maintain an increase in the amount of intake air due to both intake operations of the compressor 3 and the compressor 12.

Next, an embodiment of the present invention will be described. FIG. 3 is a schematic view showing an embodiment of the invention described in claim 3. This embodiment is characterized in that the air intake section is opened and closed according to the pressure on the intake side of the compressor in the intake path. I have. In FIG. 3, a valve housing chamber 21 that communicates with the inside of the intake passage 17 is provided in the vicinity of the air intake portion 20 having a small-diameter opening formed in the intake passage 17. The interior of the valve housing chamber 21 is partitioned into a pilot pressure setting section 21A and a negative pressure generating section 21B. The pilot pressure setting section 21A has an opening 22 communicating with the atmosphere and an air intake section 20A. An opening / closing valve 23 that can open and close is provided. The pilot pressure setting section 21A and the negative pressure generating section 21B are separated by a diaphragm 24, and are connected to the atmosphere intake section 20A.
The on-off valve 23 for opening and closing the diaphragm is provided with the diaphragm 24.
Attached to. The diaphragm 24 is normally operated by the biasing force of its own flexural rigidity, so that the
Is closed by the on-off valve 23, and when the biasing force is a pilot pressure, the on-off valve 23 is moved from the atmosphere intake unit 20 when the negative pressure in the negative pressure generation unit 21B exceeds the pilot pressure. It bends and deforms in the direction to separate. FIG.
In the state indicated by the two-dot chain line, the diaphragm 24 is bent and deformed in a direction in which the on-off valve 23 is separated from the atmosphere intake section 20. On the other hand, the negative pressure generation section 21B has a negative pressure generation path 25 that is closer to the intake section 20 of the compressor 12 than the atmosphere intake section 20 in the intake path 17 near the atmosphere intake section 20. The internal pressure is applied. In FIG. 3, arrows indicate the direction in which air flows toward the air cleaner 16 located at the intake section of the compressor 12.

Since the present embodiment has the above configuration,
When the amount of air flowing through the intake passage 17 reaches an amount corresponding to the upper limit value (minimum vacuum pressure) of the suction pressure in the injector 13, the flow rate of the air obtained by the pressure causes the air flow in the vicinity of the air intake portion 20 of the intake passage 17. The tendency to negative pressure increases. When the negative pressure in the intake path 17 increases, the negative pressure
5, the negative pressure in the negative pressure generator 21B increases. When the negative pressure in the negative pressure generating section 21B exceeds the biasing force of the diaphragm 24 (corresponding to the pilot pressure), the on-off valve 23 opens the atmosphere intake section 20, and the opening 22 provided in the pilot pressure setting section 21A and the intake passage. Air is introduced from the outside by communicating with the outside. The opening of the atmosphere intake section 20 by the on-off valve 23
Air is introduced from the outside, and the tendency of negative pressure on the intake path side of the compressor 12 is weakened, and the biasing force (pilot pressure) of the diaphragm 24 is continued until it exceeds the negative pressure in the negative pressure generating part 21B. According to the present embodiment, the pressure of the intake passage 17 in the vicinity of the atmosphere intake section 20 is made to directly act on the on-off valve 23 to open and close the atmosphere intake section 20. There is no need for a special mechanism for switching between the equipment and the on-off valve.

Next, an embodiment of the present invention will be described. FIG. 4 is a schematic view for explaining an embodiment of the invention described in claim 4, and among constituent members shown in FIG.
The same members as those shown in FIG. 1 are denoted by the same reference numerals. In the present embodiment, an air intake portion that can communicate with the atmosphere is provided in an intake passage 17 of an exhaust unit 13 that communicates with an intake portion of a compressor 12.
It is characterized in that the air can be introduced from the air intake section when the intake air amount in Step 2 corresponds to a pressure that decreases. In FIG. 4, an air flow path 30 as an air intake portion that can communicate with the atmosphere is connected to an intake path 17 that communicates from the exhaust port 13 to the intake section of the compressor 12 on an extended line. The inside of the channel 30 has the structure shown in Fig. 5. In Fig. 5, a partition wall 31 is formed inside the flow path 30, and the partition wall 31 has
An opening 32 for flowing air is formed. The partition wall 31 is provided with a leaf valve 33 serving as a control valve on a surface corresponding to the downstream side in the air introduction direction indicated by an arrow in FIG. The leaf valve 33 uses an elastic member whose base end is fixed to the partition wall 31 and whose free end can swing. The leaf valve 33 is in a position to close the opening 32 as an initial position (FIG. 5).
And the pressure acting on the intake passage 17 corresponds to the pressure at which the intake air amount in the compressor 12 decreases, as shown by the solid line in FIG. The elastic force that can release the pressure is set.
The pressure at which the amount of intake air in the compressor 12 decreases in this case is a pressure corresponding to the upper limit value (minimum vacuum pressure) of the suction pressure in the injector 13, as in the embodiment described with reference to FIGS. 1 and 3. .

Since the present embodiment has the above configuration,
When the pressure in the intake passage 17 does not reach the upper limit (minimum vacuum pressure) of the suction pressure in the injector 13, the opening 32 of the partition wall 31 provided in the atmosphere intake section 30 is closed by the leaf valve 33. . As a result, the air sucked by the eductor 13 is directly introduced into the intake section of the compressor 12 via the intake path 17. On the other hand, when the suction pressure in the eductor 13 reaches the upper limit (minimum vacuum pressure), the negative pressure tendency in the intake passage 17 becomes strong, and the leaf valve 33 swings from the initial position, and the air intake portion 30 The opening 32 of the partition wall 31 is opened. As a result, the atmosphere flows into the atmosphere intake section 30, and is introduced into the intake section of the compressor 12 through the opening provided in the partition wall 31, so that the air is supplemented.

According to the present embodiment, since the atmosphere intake section 30 is connected to the extension of the intake path 17, the flow path of the air introduced corresponding to the time when the intake amount in the compressor 12 decreases is reduced. Since there is no bending on the way, the flow resistance can be reduced as compared with the case where a curved path is interposed, thereby enabling smooth replenishment of air.

In the present invention, although not shown, a branch pipe communicating with the above-described intake passage 17 is provided at the intake section of the compressor 12 and the branch pipe is configured to communicate with the atmosphere. It is also possible to take in the air from the branch pipe in accordance with the above.

[0029]

As described above, according to the first aspect of the present invention, by providing an air intake section which can communicate with the atmosphere in an intake path for introducing suction air from the injector into the compressor, Even when the amount of intake air due to the vacuum suction force of the compressor decreases due to the influence of the vacuum suction force, air can be replenished from the air intake section to the suction section of the compressor. This makes it possible to maintain not only an increase in the intake air amount due to an increase in the suction pressure in the ejector, but also an increase in the intake air amount in which the intake air amount in the compressor itself is added, when the ejector is used.

According to the second aspect of the present invention, air can be replenished to the intake section of the compressor simply by forming a small-diameter air inlet, so that the amount of intake air in the compressor can be reduced with a simple structure. Reduction can be prevented.

According to the third aspect of the present invention, since only the on-off valve that can set the on-off valve that closes the air intake portion by the pilot pressure to the open state in accordance with the pressure change of the suction portion of the compressor is used, With a simple structure without requiring a special pressure detection structure, it is possible to prevent the intake air amount of the compressor from being reduced.

According to the fourth aspect of the invention, when the pressure in the intake passage corresponds to the pressure at which the amount of intake air in the compressor decreases, the atmosphere is forcibly introduced to replenish the amount of intake air in the compressor. Therefore, it is possible to smoothly eliminate the shortage of intake air in the compressor.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a configuration of a main part for describing an embodiment of a pump device according to the present invention.

FIG. 2 is a diagram for explaining the result of comparing the relationship between the negative pressure and the intake air amount between the case of the embodiment shown in FIG. 1 and the case of the conventional example.

FIG. 3 is a schematic diagram for explaining a main configuration for explaining an embodiment of the invention described in claim 3;

FIG. 4 is a schematic view showing a main part for explaining an embodiment of the invention described in claim 4;

FIG. 5 is a sectional view showing an internal structure of a main part shown in FIG.

FIG. 6 is a schematic diagram for explaining a configuration of a conventional pump device.

FIG. 7 is a schematic cross-sectional view for explaining an internal structure of an ejector used in the configuration shown in FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Pump apparatus 11 Engine which is an internal combustion engine 12 Compressor 13 Ejector 16 Air cleaner located in the intake part of a compressor 17 Intake path 18 Air passage 19 Connection part 20, 30 Atmospheric intake part 21 Valve accommodation chamber 21A Pilot pressure setting part 21B Negative pressure generation Part 22 Opening 23 On-off valve 24 Compression spring for pilot pressure setting 25 Negative pressure generating path 31 Partition wall 32 Opening 33 Leaf valve forming control valve

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroaki Kaneko 3-183-3 Daikan, Yamato-shi, Kanagawa Prefecture Inside the Hakko Technology Development Center Co., Ltd. (72) Inventor Nobukatsu Ike 3-183-3 Daikan, Yamato-shi, Kanagawa No. Inside the Hakko Technology Development Center Co., Ltd. (72) Minoru Nagata 3-183-3 Daikan, Yamato-shi, Kanagawa Prefecture Inside the Hakko Technology Development Center Co., Ltd. (72) Koichi Moriya 3-183-3 Daikan, Yamato-shi, Kanagawa Prefecture No. Inside the Hakko Technology Development Center

Claims (4)

[Claims] 1. A pump device comprising: an internal combustion engine; a compressor driven by the internal combustion engine; and an ejector for generating a vacuum suction force by using the air discharged from the compressor as an ejection source. A pump device provided with an air intake portion which can communicate with the atmosphere in an intake path for introducing the air into the compressor. 2. The pump device according to claim 1, wherein the air intake portion is constituted by an air inlet having a small diameter. 3. The pump device according to claim 2, wherein the air intake unit closes the air intake unit with a predetermined pilot pressure, and when the pressure of the suction unit of the compressor reaches a predetermined value or less, the air intake unit. A pump device comprising an opening / closing member for opening a part. 4. A pump device comprising: an internal combustion engine; a compressor driven by the internal combustion engine; and an ejector that generates a vacuum suction force by using the air discharged from the compressor as an ejection source. An air intake section is provided in the intake path for introducing air into the compressor, the air intake section being capable of communicating with the atmosphere.When the pressure in the intake path corresponds to the pressure at which the amount of intake air in the compressor decreases, the air intake section is A pump device provided with a control valve set to a state in which air can be introduced.