Vacuum generator and oil-free screw compressor

Abstract

The utility model discloses a vacuum generator and an oil-free screw compressor. The vacuum generator comprises a generator body, a nozzle, a filter element and a flow regulating valve. The nozzle is assembled on the generator body and comprises a nozzle inlet and a nozzle outlet. The generator body comprises an air inlet channel, an extraction opening, a backflow opening, a filtering cavity and an air outlet. The air inlet channel communicates with an external air source and the nozzle inlet. The extraction opening is communicated with the nozzle outlet and the filter cavity, and the extraction opening and the backflow opening are respectively used for connecting an extracted object. The air outlet is communicated with the filtering cavity and the outside of the vacuum generator. The filter element is located in the filter cavity. The flow regulating valve is connected with the air inlet channel. Therefore, the vacuum degree is adjusted through the nozzle, the gas flow is adjusted through the flow adjusting valve, and the problem that the gas flow cannot be adjusted when a centrifugal fan is used or the gas flow cannot be adjusted when a client site gas source is used is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vacuumizing, in particular to a vacuum generator and an oil-free screw compressor. BACKGROUND

[0002] With the development of electronic, pharmaceutical and other industries, the demand for oil-free screw compressors is also increasing. When the oil-free screw compressor is running, the oil tank inside will produce oil vapor due to the increase of oil temperature, resulting in a slight positive pressure inside the oil tank. In turn, the oil blocked by the shaft seal of the gear spindle cannot return to the oil tank normally, and even the lubricating oil stored in the oil tank is pressed back to the shaft seal of the gear spindle, thereby causing the lubricating oil to leak to the outside of the unit, bringing bad user experience to customers.

[0003] In order to solve the above problems, the first way is to use a centrifugal fan to pump the oil tank to avoid positive pressure in the oil tank. The disadvantage of the first way is that the flow of the centrifugal fan is fixed and cannot be adjusted, so the vacuum degree of the oil tank cannot be accurately adjusted, and different specifications of the oil tank need to select different specifications and models of the centrifugal fan.

[0004] The second way is to set a vacuum generator. Negative pressure is generated at the nozzle outlet of the vacuum generator, thereby pumping the oil tank. The disadvantage of the second way is that the customer's on-site gas source is needed to generate negative pressure through the nozzle to pump the oil tank, and there is no flow adjustment, thereby causing the following problems: the vacuum degree in the oil tank cannot be adjusted, the vacuum degree is too high, the pressure difference before and after the lip seal is too large, and damage is caused. When the rear oil mist filter is blocked, there is no flow adjustment device, causing the internal gas pressure of the oil tank to rise and the oil to be unable to return to the oil tank. INVENTION CONTENTS

[0005] The purpose of the present application is to disclose a vacuum generator and an oil-free screw compressor. The vacuum generator can adjust the flow of gas,

[0006] In the first aspect, the present application discloses a vacuum generator. The vacuum generator comprises a generator main body, a nozzle, a filter element and a flow regulating valve. The nozzle is assembled to the generator main body and comprises a nozzle inlet and a nozzle outlet. The generator main body comprises an air inlet channel, an air pumping port, a backflow port, a filter cavity and an air outlet; the air inlet channel is connected to an external gas source and the nozzle inlet; the air pumping port is communicated with the nozzle outlet and the filter cavity, and the air pumping port and the backflow port are respectively used for connecting the objects to be pumped; the air outlet is communicated with the filter cavity and the outside of the vacuum generator. The filter element is located in the filter cavity. The flow regulating valve is connected to the air inlet channel.

[0007] In some embodiments, the generator body is provided with a connecting channel, the connecting channel is in communication with the nozzle outlet and the filtering cavity, and is a straight channel; the angle between the center line of the nozzle outlet and the center line of the connecting channel is a, 90 degrees≤a≤180 degrees.

[0008] In some embodiments, the air inlet channel includes a straight first air inlet channel, the first air inlet channel is parallel to the connecting channel, and the nozzle is located at the side of the filtering cavity.

[0009] In some embodiments, the flow regulating valve includes a regulating valve seat and a regulating assembly, the regulating valve seat is integrally formed with the generator body; the air inlet channel is located inside the generator body and in communication with the regulating valve seat, and / or the channel between the nozzle outlet and the filtering cavity is located inside the generator body.

[0010] In some embodiments, the vacuum generator includes a solenoid valve, the solenoid valve is connected to the air inlet channel for opening and closing the air inlet channel.

[0011] In some embodiments, the solenoid valve includes a solenoid valve seat and a control assembly, the solenoid valve seat is integrally formed with the generator body; the air inlet channel is located inside the generator body and in communication with the solenoid valve seat.

[0012] In some embodiments, the nozzle has multiple types, and multiple types of the nozzle are alternatively installed on the generator body.

[0013] In some embodiments, the generator body includes a base and a shell, the base and the shell are detachably assembled, in the assembled state, the base and the shell enclose the filtering cavity; the filter core has only one type, and is detachably installed in the filtering cavity, and / or the filter core has multiple types, and is replaceably installed in the filtering cavity.

[0014] In some embodiments, the generator body includes an expansion module interface. The expansion module interface is in communication with the air inlet channel.

[0015] In a second aspect, the present application discloses an oil-free screw compressor. The oil-free screw compressor includes an object to be pumped and any one of the aforementioned vacuum generators, and the object to be pumped is an oil tank.

[0016] For the vacuum generator and the oil-free screw compressor, the vacuum generator realizes vacuum pumping of the object to be pumped, realizes adjustment of the actual vacuum degree of the object to be pumped (such as the oil tank), and avoids positive pressure, for example. The flow of gas flowing into the nozzle is adjusted by the flow regulating valve, thereby avoiding the problem that the flow of gas cannot be adjusted in the two modes of using a centrifugal fan or using a customer gas source. Attached Figure Description

[0017] Figure 1 This is a perspective view of a vacuum generator at an angle, according to an embodiment of this application;

[0018] Figure 2 This is a perspective view of a vacuum generator from another angle, according to an embodiment of this application;

[0019] Figure 3 It is along Figure 1 A cross-sectional view along line AA;

[0020] Figure 4 It is along Figure 3 A cross-sectional view of the BB line;

[0021] Figure 5 It is along Figure 1 A cross-sectional view of the CC line;

[0022] Figure 6 It is along Figure 1 A cross-sectional view of the DD line. Detailed Implementation

[0023] The technical solutions in the embodiments (or "implementations") of this application will be clearly and completely described herein with reference to the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements.

[0024] If the embodiments of this application contain terms relating to directional indications or positional relationships (such as up, down, left, right, front, back, inside, outside, top, bottom, center, vertical, horizontal, longitudinal, transverse, length, width, counterclockwise, clockwise, axial, radial, circumferential, etc.), such terms are only used to explain the relative positional relationships and movements between components in a specific posture (as shown in the attached figures); if the specific posture changes, the directional indications or positional relationships will also change accordingly. Furthermore, the terms "first" and "second" used in the embodiments of this application are only for descriptive convenience and should not be construed as indicating or implying relative importance.

[0025] See Figures 1 to 6The present application discloses a vacuum generator. The vacuum generator comprises a generator body 1, a nozzle 2, a filter 3 and a flow regulating valve 4. The nozzle 2 is assembled to the generator body 1, comprising a nozzle inlet 21 and a nozzle outlet 22. The nozzle 2 is assembled in any way, for example, by means of clamping through embedding. The generator body 1 comprises an air inlet channel 11, a suction port 12, a backflow port 13, a filter cavity 14 and an air outlet 15. The air inlet channel 11 mainly refers to the channel from the external air source to the nozzle inlet 21. The air inlet channel 11 comprises a channel inlet 111. The air inlet channel 11 is connected to the external air source through the channel inlet 111, and is also connected to the nozzle inlet 21, so that the gas generated by the external air source can enter the nozzle 2 from the nozzle inlet 21 through the air inlet channel 11, and be blown out from the nozzle outlet 22, forming a negative pressure at the nozzle outlet 22. The suction port 12 is connected to the nozzle outlet and the filter cavity 14, and the suction port 12 and the backflow port 13 are respectively used for connecting the objects to be sucked. The air outlet 15 is connected to the filter cavity 14 and the outside of the vacuum generator. The filter 3 is located in the filter cavity 14. The flow regulating valve 4 is connected to the air inlet channel 11. Referring to Figure 4 The flow regulating valve 4 comprises a regulating valve inlet 411 and a regulating valve outlet 412, so that the air inlet channel 11 comprises two sections, the regulating valve inlet 411 is connected to the outlet of one section of the air inlet channel, and the regulating valve outlet 412 is connected to the inlet of the other section of the air inlet channel, and the outlet of the other section of the air inlet channel is connected to the nozzle inlet 21.

[0026] In combination Figures 1 to 4 and Figure 6 , Figure 3 、 Figure 4 and Figure 6 The flow direction of the gas is shown by the dashed arrows. In combination with the flow direction, the process of sucking air by the above-mentioned vacuum generator is described as follows: the gas generated by the external air source is blown in through the air inlet channel 11. The gas flows into the nozzle 2 through the flow regulating valve 4. The flow into the nozzle 2 can be adjusted by the flow regulating valve 4. The gas enters the nozzle 2 from the nozzle inlet 21 and is blown out from the nozzle outlet 22 of the nozzle 2, forming a negative pressure. Because the suction port 12 is connected to the nozzle outlet 22, the object to be sucked (for example, an oil tank) is sucked through the air outlet 15, and the vacuum degree of the object to be sucked is adjusted, for example, to avoid the positive pressure of the object to be sucked. The gas blown out from the nozzle outlet 22 of the nozzle 2 enters the filter cavity 14 (in the embodiment of the present application, the oil tank is sucked, and thus, the mixture of oil and gas enters the filter cavity 14); under the action of the filter 3 in the filter cavity 14, the gas is discharged from the air outlet 15, and the filtered substance (in this embodiment, oil) returns to the object to be sucked (the oil tank) from the backflow port 13.

[0027] As set forth above, since the vacuum generator realizes vacuumizing of the vacuumized object, adjustment of the vacuum degree of the vacuumized object (such as the oil tank) is realized, such as avoiding positive pressure, and in turn, avoiding problems such as oil being unable to return to the oil tank, or lubricating oil leakage. By adjusting the flow of the gas flowing into the nozzle 2 through the flow regulating valve 4, the problem that the flow of the gas cannot be adjusted in the two ways of using a centrifugal fan or using a customer gas source is avoided, such as being able to well adjust the vacuum degree of the vacuumized object (such as the oil tank), without selecting different centrifugal fans for different specifications of oil tanks, the lip seal is not easy to damage, and the oil mist filter is not easy to block.

[0028] Referring to Figure 3 , Figure 4 and Figure 6 , the generator body 1 is provided with a connecting channel 16. The connecting channel 16 is in communication with the nozzle outlet 22 and the filter cavity 14. The connecting channel 16 is a straight channel. The included angle formed by the center line of the nozzle outlet 22 and the center line of the connecting channel 16 is a, and in Figure 4 , a = 90 degrees. The skilled person can understand that 90 degrees ≤ a ≤ 180 degrees, such as 90 degrees, 92 degrees, 95 degrees, 98 degrees, 100 degrees, 105 degrees, 108 degrees, 110 degrees, 112 degrees, 115 degrees, 118 degrees, 120 degrees, 123 degrees, 125 degrees, 128 degrees, 130 degrees, 135 degrees, 138 degrees, 140 degrees, 143 degrees, 145 degrees, 148 degrees, 150 degrees, 153 degrees, 155 degrees, 158 degrees, 160 degrees, 162 degrees, 165 degrees, 168 degrees, 170 degrees, 173 degrees, 175 degrees, 178 degrees, or 180 degrees.

[0029] As set forth above, for 90 degrees ≤ a ≤ 180 degrees, the smaller the angle, the closer the filter cavity 14 to the nozzle 2, the structure of the vacuum generator is compact, but the smaller the angle, the relatively larger the pressure loss ratio of the gas, the smaller the gas flow, and the vacuum in the vacuumized object (the oil tank) is not easy; and the larger the angle, the closer the nozzle 2 to the connecting channel 16, so that the filter cavity 14 is away from the nozzle 2, and the structure of the vacuum generator is not too compact, but because the closer to the straight line, the smaller the resistance to the gas, the relatively smaller the pressure loss ratio of the gas flow, the larger the gas flow, and the vacuum in the vacuumized object is easy.

[0030] Referring to Figure 3 and Figure 4 , the gas inlet channel 11 includes a straight first gas inlet channel 112, the first gas inlet channel 112 is parallel to the connecting channel 16, and the nozzle 2 is located at the side of the filter cavity 14.

[0031] As set forth above, the gas combined with the gas inlet channel 11 enters the nozzle 2 from the nozzle inlet 21, and is discharged from the nozzle outlet 22, and then enters the filter cavity 14 through the connecting channel 16, so that when the nozzle 2 is located at the side of the filter cavity 14, the structure of the vacuum generator is compact, the flow path of the gas is short, and the pressure loss ratio is reduced.

[0032] Referring to Figure 1 , Figure 3 , Figure 4 and Figure 5 , the flow regulating valve 4 comprises a regulating valve seat 41 and a regulating assembly (not labeled in the figure), and the regulating valve seat 41 is integrally formed with the generator body 1, for example, integrally formed by casting or integrally formed by 3D printing. The gas inlet channel 11 is located inside the generator body 1 and communicates with the regulating valve seat 41.

[0033] As set forth above, by locating the gas inlet channel 11 inside the generator body 1 and integrally forming the regulating valve seat 41 with the generator body 1, the gas inlet channel 11 itself and the channel connecting the gas inlet channel 11 and the regulating valve seat 41 are formed on the generator body 1, thereby omitting the joint connecting the flow regulating valve 4 and the gas inlet channel 11 of the generator body 1 and the joint connecting the flow regulating valve 4 and the nozzle 2, and saving materials.

[0034] In some embodiments, the channel (such as the connecting channel 16) between the nozzle outlet 22 and the filter cavity 14 is located inside the generator body 1. In this way, the joint connecting the nozzle 2 and the filter cavity 14 or the filter element 3 is also omitted, and materials are saved.

[0035] Referring to Figure 1 and Figure 2 , the vacuum generator comprises a solenoid valve 5 connected to the gas inlet channel 11 for opening and closing the gas inlet channel 11.

[0036] Generally, an external gas source always supplies gas, and the solenoid valve 5 realizes the on-off control of the external gas source. When gas is not needed, the solenoid valve 5 is closed to shut off the gas inlet channel 11, so that in the shutdown state of the oil-free screw compressor, the gas of the customer's gas source is not wasted.

[0037] In some embodiments, the solenoid valve 5 comprises a solenoid valve seat and a control assembly, and the solenoid valve seat is integrally formed with the generator body 1; the gas inlet channel 11 is located inside the generator body 1 and communicates with the solenoid valve seat. In the case where both the solenoid valve 5 and the flow regulating valve 4 are provided, their positional relationship is not limited. Referring to Figure 1 and Figure 5 , the solenoid valve 5 is stacked on the flow regulating valve 4, Figure 5The electromagnetic valve inlet 51 of the electromagnetic valve 5 and the electromagnetic valve outlet 52 are shown. The electromagnetic valve inlet 51 is connected with the regulating valve outlet 412 of the flow regulating valve 4, and the electromagnetic valve outlet 52 is connected with the nozzle inlet 21.

[0038] As set forth above, since the electromagnetic valve seat is integrally formed with the generator body 1, and the air inlet channel 11 is located inside the generator body 1 and communicates with the electromagnetic valve seat, the joint between the electromagnetic valve 5 and the air inlet channel 11 can be omitted, thereby saving materials.

[0039] Referring to Figure 3 and Figure 4 , the nozzle 2 and the generator body 1 are detachably assembled. In this way, when the nozzle 2 is damaged, the good nozzle 2 can be replaced. Alternatively, there are multiple nozzles, and the vacuum degrees formed by the multiple nozzles are different. The multiple nozzles are selectively installed on the generator body 1. In this way, different nozzles can be matched according to different air source pressures and air volume requirements of the object (oil tank) to be pumped, and the vacuum generator is more convenient to use.

[0040] Referring to Figure 1 , Figure 2 and Figure 6 , the generator body 1 includes a base 110 and a shell 120. In the case where the air inlet channel 11 and the like are provided in the generator body 1, the generator body 1 can be an aluminum casting. The base 110 and the shell 120 are detachably assembled, and in the assembled state, the base 110 and the shell 120 enclose the filter cavity 14. There is only one type of filter element 3, which is detachably installed in the filter cavity 14. The vacuum generator of the present application is used in an oil-free screw compressor, and therefore the filter element 3 is an oil mist filter.

[0041] As set forth above, since the base 110 and the shell 120 are detachably assembled, and the filter element 3 is detachably assembled, when the filter element 3 is damaged, the filter element 3 can be replaced.

[0042] In other embodiments, there are multiple types of filter elements 3, which are replaceably installed in the filter cavity 14.

[0043] As set forth above, different precision filter elements 3 can be matched according to requirements, and the vacuum generator is more convenient to use.

[0044] Referring to Figures 1 to 5 , the generator body 1 includes an expansion module interface 17. The expansion module interface 17 communicates with the air inlet channel 11. The expansion module interface 17 is connected with external devices according to requirements, for example, a back flushing device.

[0045] As set forth above, by setting the extension module interface 17, the function of the vacuum generator can be extended, and the vacuum generator is more convenient to use.

[0046] In a second aspect, the application discloses an oil-free screw compressor. The oil-free screw compressor comprises an object to be pumped and the vacuum generator of any one of the preceding aspects. The object to be pumped is an oil tank. The vacuum generator comprises an automatic blowdown valve 18 located in the filter cavity 14. The automatic blowdown valve 18 is connected to the backflow port (hereinafter referred to as an oil return interface) 13. The oil flows into the oil tank from the backflow port 13 after being decontaminated.

[0047] It should be noted that the technical solutions or technical features described in the above embodiments can be combined or supplemented with each other without conflict. The scope of protection of the present application is not limited to the precise structures described in the above embodiments and shown in the accompanying drawings; any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A vacuum generator, characterized by The vacuum generator comprises a generator body, a nozzle, a filter element and a flow regulating valve; wherein: The nozzle is assembled to the generator body and comprises a nozzle inlet and a nozzle outlet; The generator body comprises an air inlet channel, a suction port, a backflow port, a filter cavity and an air outlet; the air inlet channel is connected to an external air source and the nozzle inlet; the suction port and the backflow port are respectively connected to the nozzle outlet and the filter cavity; the air outlet is connected to the filter cavity and the outside of the vacuum generator; The filter element is located in the filter cavity; The flow regulating valve is connected to the air inlet channel.

2. The vacuum generator of claim 1, wherein, The generator body is provided with a connecting channel, which is connected to the nozzle outlet and the filter cavity and is a straight channel; the included angle between the center line of the nozzle outlet and the center line of the connecting channel is a, and 90 degrees≤a≤180 degrees.

3. The vacuum generator of claim 2, wherein, The air inlet channel comprises a straight first air inlet channel, which is parallel to the connecting channel; the nozzle is located at the side of the filter cavity.

4. The vacuum generator of claim 1, wherein, The flow regulating valve comprises a regulating valve seat and a regulating assembly; the regulating valve seat is integrally formed with the generator body; the air inlet channel is located in the interior of the generator body and is connected to the regulating valve seat, and / or the channel between the nozzle outlet and the filter cavity is located in the interior of the generator body.

5. The vacuum generator of claim 1, wherein, The vacuum generator comprises a solenoid valve, which is connected to the air inlet channel.

6. The vacuum generator of claim 5, wherein, The solenoid valve comprises a solenoid valve seat and a control assembly; the solenoid valve seat is integrally formed with the generator body; the air inlet channel is located in the interior of the generator body and is connected to the solenoid valve seat.

7. The vacuum generator of claim 1, wherein, The nozzle has multiple types, and the multiple types of the nozzle are selectively installed to the generator body.

8. The vacuum generator of claim 1, wherein, The generator body comprises a base and a shell; the base and the shell are detachably assembled; in the assembled state, the base and the shell enclose the filter cavity; The filter element has only one type and is detachably installed in the filter cavity, and / or the filter element has multiple types and is replaceably installed in the filter cavity.

9. The vacuum generator of claim 1, wherein, The generator body comprises an expansion module interface, which is connected to the air inlet channel.

10. An oil-free screw compressor, characterized by The oil-free screw compressor comprises an object to be pumped and the vacuum generator according to any one of claims 1 to 9; the object to be pumped is an oil tank.

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