CN212615656U

CN212615656U - Automatic flow speed control device for jet vacuum pump

Info

Publication number: CN212615656U
Application number: CN202021438237.5U
Authority: CN
Inventors: 高超
Original assignee: Shandong Shengquan Energy Saving And Environmental Protection Service Co ltd
Current assignee: Shandong Shengquan Energy Saving And Environmental Protection Service Co ltd
Priority date: 2020-07-21
Filing date: 2020-07-21
Publication date: 2021-02-26
Anticipated expiration: 2030-07-21

Abstract

The automatic flow rate control device of the jet vacuum pump comprises a switching power supply, a proportional-integral electric three-way regulating valve, a control circuit and a detection probe; the detection probe comprises a cylinder, a sliding adjustable resistor, a rubber piston, a permanent magnet, a limiting plate and a spring; a support plate is arranged at the upper end in the cylinder body, and the adjustable resistor is arranged in front of the support plate; the side end of the adjustable resistance handle is provided with a connecting rod, and the magnet and the piston are arranged in the middle of the connecting rod; the spring is sleeved under the piston; the limiting plate is arranged below the cylinder body and is provided with an air vent; the regulating valve outlet fluid pipe is connected with a fluid inlet pipe of a fluid spray pipe of the jet type vacuum pump body, and the regulating valve inlet fluid pipe is connected with an outlet fluid pipe of high-speed input jet fluid generation equipment; the cylinder is arranged at the side end of a lower pipeline of a pump shell of the jet vacuum pump body; the control circuit comprises a reed switch and a relay, the control circuit is arranged in the shell, the shell is sleeved at the outer side end of the barrel, and the switching power supply is arranged in the electrical control box. This novel vacuum that can keep production facility to set for.

Description

Automatic flow speed control device for jet vacuum pump

Technical Field

The utility model relates to a jet type vacuum pump corollary equipment field, especially a jet type vacuum pump velocity of flow automatic control device.

Background

The jet vacuum pump belongs to a fluid action pump, also called a jet vacuum pump, and the main principle is a device for transferring fluid by utilizing energy conversion when the fluid flows. The working fluid of the jet pump may be water vapor, air, water, oil, and the like. When the device works, high-speed jet fluid input from the outside enters a pump shell from a fluid spray pipe and is then discharged from a fluid outlet pipe, the high-speed jet fluid generates vacuum in the lower middle pipeline lower end in the pump shell, so that the production equipment connected with the pipeline in a sealing manner generates vacuum, and then working medium fluid in the production equipment enters corresponding pipelines of the production equipment along with the jet fluid discharged from the fluid outlet pipe, so that the working medium fluid is conveyed from a low position to a high position. Or the upper part in the production equipment generates vacuum to meet the requirement of the related production equipment for the vacuum degree of the processed products (for example, the upper end of a reaction kettle adopted in chemical production generates vacuum to meet the requirement of the vacuum degree of the processed products in the reaction kettle).

In the field of using the jet vacuum pump, according to the production requirement, the flow velocity and the flow quantity of the working medium fluid of the production equipment are often required to be controlled, or the vacuum degree in the production equipment is required to be controlled, so that the actual production requirement of the production equipment is met. The vacuum degree control in the present jet vacuum pump for the working equipment is controlled by controlling the opening and closing degree of a valve core of the external high-speed input jet fluid generation equipment, when the flow rate of the input high-speed jet fluid is relatively small, the vacuum degree generated by a working medium fluid pipe of the production equipment is relatively small, and when the flow rate of the input high-speed jet fluid is relatively large, the vacuum degree generated by the working medium fluid pipe of the production equipment is relatively large. In practical situations, when the external high-speed input jet fluid generating device generates a high-speed jet fluid flow change due to various reasons (for example, the amount of compressed air input by the air compressor causes the rotation speed of the motor of the air compressor to decrease or increase due to fluctuation of the operating power supply, the output gas flow becomes smaller or larger, or other devices using the air compressor stop using the compressed air output by the air compressor, the output gas flow becomes larger, or other devices using the air compressor use a large amount of compressed air in a short time, and the output gas flow becomes smaller, etc.), then, due to the change of the input high-speed jet fluid flow, the vacuum degree in the production device is correspondingly changed, so that the effect of stabilizing the vacuum degree in the production device cannot be achieved, and the normal production of the production device is affected.

SUMMERY OF THE UTILITY MODEL

In order to overcome the defects that the vacuum degree in the production equipment can not be effectively ensured to be in a constant state and the normal production of the production equipment can be adversely affected because the manual operation is adopted for adjusting the vacuum degree in the production equipment in the application of the existing jet vacuum pump, the utility model provides a detection probe which can set the vacuum degree in the production equipment according to the requirement, and the proportional integral electric three-way regulating valve is adopted to replace the valve of the existing manual high-speed input jet fluid generating equipment, when the vacuum degree in the production equipment is too high, the high-speed jet fluid input flow can be automatically reduced, and when the vacuum degree in the production equipment is too low, the high-speed jet fluid input flow of the jet fluid generation equipment can be automatically increased and input at high speed, thereby satisfying the vacuum degree in the production equipment and being in the range set by the user, and ensuring the normal production of the production equipment.

The utility model provides a technical scheme that its technical problem adopted is:

the automatic flow rate control device for the jet vacuum pump comprises a switching power supply and a proportional-integral electric three-way regulating valve, and is characterized by also comprising a control circuit and a detection probe; the detection probe comprises a cylinder, a linear sliding adjustable resistor, a rubber piston, a permanent magnet, a limiting plate and a spring; the linear sliding adjustable resistor is vertically arranged at the upper end in the cylinder body, and the middle part in the cylinder body is provided with a partition plate; the connecting rod is arranged at the handle side end of the linear sliding adjustable resistor, the connecting rod is led out downwards through an opening in the middle of the isolating plate, and the magnet and the piston are arranged in the middle of the connecting rod; the spring is sleeved at the lower end of the piston; the limiting plate is arranged at the inner lower part of the cylinder body and is provided with a guide hole, and a plurality of vent holes are distributed at the side end of the guide hole; the integral electric three-way regulating valve is connected with an outlet fluid pipe of a fluid spray pipe of the jet type vacuum pump body, and the inlet fluid pipe of the integral electric three-way regulating valve is connected with an outlet fluid pipe of high-speed input jet fluid generating equipment; the cylinder body is arranged at the side end of a lower pipeline of a pump shell of the jet vacuum pump body; the control circuit comprises a reed switch and a relay, the control circuit is arranged in an annular shell, the shell is sleeved at the outer side end of the barrel, and the switching power supply is arranged in the electric control box; the positive electrode of the control power supply output end of the control circuit, the negative power supply output end of the switching power supply and the two ends of the power supply input of the proportional-integral electric three-way regulating valve are respectively and electrically connected; the other end of the sliding adjustable resistor, the negative power output end of the switching power supply and the two signal input ends of the proportional-integral electric three-way regulating valve are respectively and electrically connected.

Further, the switching power supply is an alternating current to direct current switching power supply module.

Furthermore, the annular shell is of an inner-outer layer structure, the inner side end of the middle part of the annular shell is provided with an annular through hole, the annular shell through hole is sleeved at the outer side end of the cylinder body, the annular shell through hole and the cylinder body are in a close contact state, the reed switch is vertically installed on the inner side of the inner layer of the shell, and the outer side of the inner layer of the relay shell is vertically installed on the.

Furthermore, when the side ends of a reed switch and a magnet of the control circuit are close to the horizontal level, the magnetic acting force of the magnet can act on the reed switch, a fixed contact and a movable contact inside the reed switch are closed, one end of the reed switch is connected with the positive power input end of the relay through a lead, the other end of the reed switch is connected with the control power input end of the relay through a lead, the two power input ends of the relay are respectively connected with the positive pole and the negative pole of a light-emitting diode, and a resistor is arranged between the positive pole of the light-emitting diode and the positive power input end of the relay.

The utility model has the advantages that: this is novel, vacuum in the test probe ability real-time detection production facility, piston and magnet down distance are big when vacuum is big, otherwise just little, vacuum in the production facility is higher than or is less than the user when adjusting the value that annular shell set for, control circuit, straight line sliding resistance enables the input voltage signal of proportion integral electric three-way control valve step-down or uprise, and then, under the effect such as proportion integral electric three-way control valve internal control circuit, the case of proportion integral electric three-way control valve is by its inside electric actuator, adjust corresponding little or big a little, just so can keep outside high-speed input jet fluid production equipment, the fluid jet pipe that inputs to jet vacuum pump advances in the intraductal in the suitable scope of setting for fluid, and then guaranteed the normal production of production facility. Based on the above, this is novel has good application prospect.

Drawings

The present invention will be further explained with reference to the drawings and examples.

Fig. 1 is a schematic structural diagram of the present invention.

Fig. 2 is the schematic view of the local enlarged structure of the detecting probe and the annular housing of the present invention.

Fig. 3 is a circuit diagram of the present invention.

Detailed Description

As shown in fig. 1 and 2, the automatic flow rate control device for the jet vacuum pump comprises a switching power supply 1, a proportional-integral electric three-way regulating valve 2, a control circuit 3 and a detection probe 4; the detection probe 4 comprises a cylinder 41, a linear sliding adjustable resistor 42, a circular rubber piston 43, a circular permanent magnet 44, a limiting plate 45 and a spring 49, wherein the upper end of the cylinder is closed, the lower end of the cylinder is open, and the outer side of the lower end of the outer side of the cylinder is provided with an external thread; the rear part of the inner upper end of the cylinder body 41 is provided with a rectangular supporting plate 46 which is integrally formed and vertically distributed, the linear sliding adjustable resistor 42 is vertically arranged on a rectangular circuit board (a lead connected with the adjustable resistor 42 is led out from an opening at the upper end of the cylinder body 41, the opening is sealed by glue), the circuit board is vertically connected to the left end of the front side of the supporting plate 46 by the glue, and the middle part in the cylinder body at the lower end of the supporting plate 46 is provided with a separation plate 47 which is integrally formed with the cylinder body and is provided with an; a connecting rod 48 which is vertically distributed is installed at the right end of the handle of the linear sliding adjustable resistor 42 through hot melting welding, the connecting rod 48 is led out downwards through an opening in the middle of the isolation plate 47, the lower end of the connecting rod 48 is sequentially sleeved in openings in the middle of the permanent magnet 44 and the rubber piston 43 from top to bottom, and the magnet 44 and the piston 43 are fixed in the middle of the connecting rod 48 through external threads in the middle of the connecting rod 48 by two nuts (the upper end and the lower end of the piston 43 are provided with metal gaskets with outer diameters smaller than the inner diameter of the cylinder 41, and the magnet 44 and the piston 43 are; the spring 49 is sleeved at the lower end of the piston 43 and is positioned in the lower end of the cylinder 41; the lower end of the cylinder body 41 is internally provided with an internal thread, the circular limiting plate 45 is screwed into the internal thread of the lower end of the cylinder body 41 through the external thread of the circular limiting plate 45 and is arranged at the lower part in the cylinder body 41, the middle part of the limiting plate 45 is provided with a guide hole, a plurality of vent holes 451 are distributed at the side end of the guide hole, the lower end of the connecting rod 48 is led out to the lower end of the limiting plate 45 through a hole at the middle part of the limiting plate 45, and; the outflow pipe of the integral electric three-way regulating valve 2 is connected with the inflow pipe 51 of the fluid spray pipe of the jet vacuum pump body 5 through a pipeline joint, and the inflow pipe of the integral electric three-way regulating valve 2 is connected with the outflow pipe of the high-speed input jet fluid generating equipment through a pipeline joint; the right side end of the lower middle pipeline 521 in the pump shell 52 of the jet vacuum pump body is provided with an opening with internal threads, and the cylinder body 51 is transversely screwed into the internal threads of the opening at the right side end of the lower middle pipeline 521 in the pump shell through external threads at the lower end so as to be transversely arranged at the right outer side end of the lower middle pipeline 521 in the pump shell; the control circuit 3 comprises a reed switch 31 and a relay 32, the control circuit 3 is installed in an annular shell 6, the shell 6 is sleeved at the outer end of the cylinder 41, and the switching power supply 1 is installed in the electrical control box 7. The outer diameter of the rubber piston 43 is 1.5mm larger than the inner diameter of the cylinder 41 (effective sealing between the piston 43 and the inside of the cylinder 41 is realized), and the outer diameter of the magnet 43 is slightly smaller than the inner diameter of the cylinder 41 by 2 mm. The annular shell 6 is of an inner-layer structure and an outer-layer structure, the inner side end of the middle part of the annular shell is vertically provided with an annular through hole 61, the annular shell 6 is sleeved at the outer side end of the cylinder 41 through the through hole of the annular shell and is in a close contact state between the annular shell and the cylinder 41, the annular shell 6 cannot move up and down along the cylinder 41 under the action of no large vertical external force, the reed pipe 31 is vertically connected to the inner side of the inner layer of the shell 6 through glue, the movable contact of the reed pipe is vertically positioned at the inner end of the inner side, the static contact of the reed pipe is vertically.

As shown in FIG. 3, the switching power supply A is a finished product of a brand bright weft AC 220V-to-12V DC switching power supply module with the power of 100W. The proportional integral electric three-way regulating valve A1 is a finished product of a proportional integral electric three-way regulating valve of brand ZGFV/Fanwei, has working voltage of direct current 12V and is provided with two

power input ends

1 and 2 pins (grounded) and two

signal input ends

3 and 4 pins (grounded), and when a voltage signal gradually changing between 0 and 10V is input into the two

signal input ends

3 and 4 pins during working, an internal electric actuating mechanism (M) of the proportional integral electric three-way regulating valve A1 can respectively control the valve core of the proportional integral electric three-way regulating valve to be excessive from a closed state to a full-open state. When the middle parts of the side ends of a reed switch GH and a magnet CT of the control circuit are close to the horizontal level, the magnetic acting force of the magnet CT acts on the reed switch GH, a fixed contact and a movable contact inside the reed switch GH are closed, one end of the reed switch GH is connected with the positive power input end of a relay J through a lead, the other end of the reed switch GH is connected with the control power input end of the relay J through a lead, the two ends of the power input of the relay J are respectively connected with the positive pole and the negative pole of a light emitting diode VL (the light emitting surface is positioned on the outer side of the shell 6), and a resistor R is arranged between the positive pole of the light emitting diode VL.

Pins

1 and 2 at the power input end of a switching power supply A and two poles of an alternating current 220V power supply are respectively connected through leads,

pins

3 and 4 at the power output end of the switching power supply A, the other ends of reed pipes GH at the power input ends of a control circuit and the power input end of a negative electrode of a relay J are respectively connected through leads, and the normally closed contact end of a positive electrode relay J at the control power output end of the control circuit, the pin 4 at the negative electrode power output end of the switching power supply A and the

pins

1 and 2 at the power input ends of a proportional-integral electric three-way regulating valve are respectively connected through; the 3 pins of the positive power output end of the switch power supply A are connected with one end of the sliding adjustable resistor RP through leads, and the other end of the sliding adjustable resistor RP, the 4 pins of the negative power output end of the switch power supply A and the 3 and 4 pins of the two signal input ends of the proportional-integral electric three-way regulating valve A1 are respectively connected through leads.

As shown in fig. 1, 2 and 3, the height of the annular shell 6 at the outer end of the cylinder 41 needs to be adjusted according to the required vacuum degree of the production equipment before the novel vacuum pump is used (the adjustment process and the application principle are specifically replaced later). After a 220V alternating current power supply is input into a switching power supply A, under the action of an internal circuit of the switching power supply A,

pins

3 and 4 of the switching power supply A can output a stable 12V direct current power supply to enter two power supply input ends of a control circuit, and then the control circuit is in a power-on working state. In this novel, after jet vacuum pump body 5 got electric work, the high-speed efflux body of outside high-speed input efflux body production facility (there is manual valve between its fluid output end and the proportional control valve A1 in addition) output gets into in the pump case 52 from fluid spray pipe 51, the electronic three way control valve A1 of proportion integral that the case was opened, then discharge from the fluid exit tube, high-speed efflux produces the vacuum in middle part pipeline 521 lower extreme under in the pump case, then, produce the vacuum in the production facility that links to each other with pipeline 521 seals, and then the working medium fluid in the production facility gets into the corresponding pipeline of production facility along with the efflux of injection through the fluid exit tube discharge. When vacuum is generated in the production equipment, negative pressure vacuum in the production equipment is communicated with the inner lower end of the piston 43 of the detection probe through the plurality of vent holes 451 of the limiting plate, so that the negative pressure vacuum can act on the piston 43, the distance for the piston 43 to move downwards against the upward elastic acting force of the spring 49 is larger when the vacuum degree is larger, and the distance for the piston 43 to move downwards against the upward elastic acting force of the spring 49 is relatively smaller when the vacuum degree is smaller (when the vacuum degree is reduced from large to small, the spring 49 can push the piston 43 to move upwards); thus, when the piston 43 moves upwards or downwards, the connecting rod 48 drives the adjusting handle of the sliding adjustable resistor RP to move upwards or downwards, and further, the resistance value of the adjustable resistor RP changes correspondingly, when the adjusting handle of the adjustable resistor RP moves downwards, that is, when the vacuum degree in the production equipment is larger, the resistance value of the adjustable resistor RP is relatively higher, and when the adjusting handle of the adjustable resistor RP moves upwards, that is, when the vacuum degree in the production equipment is smaller, the resistance value of the adjustable resistor RP is relatively smaller. In the novel vacuum valve, when the vacuum degree in production equipment is lower than the vacuum degree set by a user, namely the magnet CT on the piston is positioned at the upper end of the reed pipe GH, so that the magnetic acting force of the magnet CT does not act on the reed pipe GH, the internal contact of the reed pipe GH is opened, the relay J cannot be electrified and attracted, then the positive pole of a 12V power supply enters a power supply input end 1 pin (2 pins are grounded) of the proportional-integral electric three-way regulating valve A1 through the control power supply input end and the normally closed contact end of the relay J, and then the proportional-integral electric three-way regulating valve A1 is in an electrified working state; because the resistance value of the adjustable resistor RP is relatively small at the moment, the voltage signal of the 12V power supply anode after being subjected to voltage reduction and current limitation by the adjustable resistor RP is relatively high, so that the signal voltage entering the pin 3 of the signal input end of the proportional-integral electric three-way regulating valve A1 is relatively high, and under the action of an internal circuit of the proportional-integral electric three-way regulating valve A1, an internal electric actuating mechanism can regulate the opening degree of a valve core to be larger, and the flow rate of high-speed jet fluid output by external high-speed input jet fluid generating equipment entering the pump shell 52 from the fluid spray pipe 51 can be increased; since the flow rate and the flow velocity of the high-speed jet fluid entering the pump case 52 from the fluid nozzle 51 become large, the vacuum degree generated in the production equipment hermetically connected to the pipe 521 after the high-speed jet fluid is discharged from the fluid outlet pipe also becomes large slowly; when the vacuum degree is gradually increased, the piston can drive the connecting rod 48 to move downwards, when the vacuum degree reaches a value set by a user, namely the magnet CT moves downwards along with the piston 43, the side end and the reed switch GH are in a level close to the horizontal level, the magnetic acting force of the magnet CT can act on the reed switch GH, the internal static contact and the movable contact of the reed switch GH are closed, thus, the 12V power supply positive electrode can enter the power supply input end of the positive electrode of the relay J through the reed switch GH with the closed contact (meanwhile, the light-emitting diode VL is electrified to emit light, the resistor R plays a role in reducing voltage and limiting current), the relay J is electrified to attract the control power supply input end and the normally closed contact end to be open, further, the proportional integral electric three-way regulating valve A1 does not work after power loss, the electric actuator does not control the valve core to generate opening change any more, the flow and the flow rate of high-speed jet fluid output by the external high-speed input jet fluid generating, namely, the vacuum degree of the production equipment is at the value set by a user, and the actual production requirement is met.

As shown in fig. 1, 2 and 3, in the present invention, when the vacuum degree in the production equipment is higher than the vacuum degree set by the user, that is, the magnet CT on the piston is located at the lower end of the reed pipe GH, so the magnetic acting force of the magnet CT does not act on the reed pipe GH, the internal contact of the reed pipe GH is open, the relay J is not powered on for actuation, and then the 12V power supply positive electrode enters the power supply input end 1 pin (2 pins are grounded) of the proportional-integral electric three-way regulating valve a1 through the relay J control power supply input end and the normally closed contact end, so the proportional-integral electric three-way regulating valve a1 is in a powered on working state; because the resistance value of the adjustable resistor RP is relatively large at the moment, the voltage signal of the 12V power supply anode after being subjected to voltage reduction and current limitation by the adjustable resistor RP is relatively low, so that the signal voltage entering the pin 3 of the signal input end of the proportional-integral electric three-way regulating valve A1 is relatively low, and under the action of an internal circuit of the proportional-integral electric three-way regulating valve A1, an internal electric actuating mechanism can regulate the opening degree of a valve core to be smaller, and the flow rate of high-speed jet fluid output by external high-speed input jet fluid generation equipment entering the pump shell 52 from the fluid spray pipe 51 are both smaller; since the flow rate and flow velocity of the high-speed jet fluid entering the pump housing 52 from the fluid nozzle 51 become small, the vacuum generated in the production equipment hermetically connected to the pipe 521 will also become small slowly after the high-speed jet fluid is discharged from the fluid outlet pipe; when the vacuum degree is slowly reduced, the piston can drive the connecting rod 48 to move upwards, when the vacuum degree reaches a value set by a user, namely the magnet CT moves upwards along with the piston 43, the side end and the reed switch GH are close to the horizontal level, the magnetic acting force of the magnet CT can act on the reed switch GH, the internal static contact and the movable contact of the reed switch GH are closed, thus, the positive pole of a 12V power supply can enter the positive pole power supply input end of the relay J through the reed switch GH with the closed contacts (meanwhile, the light emitting diode VL obtains electric light, the resistor R plays a role of reducing voltage and limiting current), the relay J obtains electricity to attract the control power supply input end and the normally closed contact end to be open, further, the proportional integral electric three-way regulating valve A1 is not operated when power is lost, the electric actuating mechanism does not control the valve core to generate opening change any more, the flow and the flow rate of high-speed jet fluid output by the external high-speed input pump shell generating, namely, the vacuum degree in the production equipment is at the value set by a user, and the actual production requirement is met. Through the aforesaid, this is novel just can effectively realize that the vacuum of production facility is in the position that the user needs.

As shown in fig. 1, 2 and 3, before the vacuum degree adjusting device is used, the height of the annular shell 6 at the outer end of the cylinder 41 is adjusted according to the required vacuum degree of the production equipment, namely, the required vacuum degree of the production equipment is adjusted, when the jet vacuum pump body 5 works, a user adjusts the vacuum degree according to the display number of a vacuum meter on the production equipment, when the adjustment is performed, the size of a manual valve of the jet fluid generation equipment is manually operated, when the vacuum degree of the production equipment reaches the required number, the manual valve is not adjusted, then the annular shell 6 is adjusted up and down along the outer side of the cylinder 41, when the magnetic acting force of the magnet CT is adjusted to act on the reed switch GH, and the relay J is not adjusted after being electrified and attracted (the light emitting diode VL emits light for indication); after the adjustment is finished, the size of a manual valve of the external high-speed input jet fluid generation equipment is manually operated, so that the external high-speed input jet fluid generation equipment is in a valve core full-open state. Thus, in the subsequent actual operation, when the high-speed jet fluid generation device generates high-speed jet fluid flow change due to various reasons (for example, the input compressed air quantity of the air compressor causes the rotating speed of the motor of the air compressor to decrease or increase due to the fluctuation of the working power supply, and the output gas flow becomes smaller or larger, or other devices using the air compressor stop using the compressed air output by the air compressor, and the output gas flow becomes larger, or other devices using the air compressor use a large amount of compressed air in a short time, and the output gas flow becomes smaller), under the combined action of the detection probe, the control circuit and the like, the high-speed jet fluid output by the proportional-integral electric three-way regulating valve A1 can be kept at a proper flow speed and flow rate, namely, the vacuum degree of production equipment required by a user can be kept all the time without being influenced by external factors, so that the actual production requirement can be effectively met. The resistance value of the resistor R is 1.8K; the resistance value of the adjustable resistor RP is 4.7M; the reed switch GH is a normally open contact type reed switch with a glass shell; the light emitting diode VL (33) is a red light emitting diode, and the light emitting surface of the light emitting diode is positioned outside the opening at the front outer end of the shell so that a user can observe the light emitting condition of the light emitting diode to adjust the required vacuum degree of the production equipment; relay J is a DC4100 type 12V relay.

The essential features of the invention and the advantages of the invention have been shown and described above, it will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.

Claims

1. The automatic flow rate control device for the jet vacuum pump comprises a switching power supply and a proportional-integral electric three-way regulating valve, and is characterized by also comprising a control circuit and a detection probe; the detection probe comprises a cylinder, a linear sliding adjustable resistor, a rubber piston, a permanent magnet, a limiting plate and a spring; the linear sliding adjustable resistor is vertically arranged at the upper end in the cylinder body, and the middle part in the cylinder body is provided with a partition plate; the connecting rod is arranged at the handle side end of the linear sliding adjustable resistor, the connecting rod is led out downwards through an opening in the middle of the isolating plate, and the magnet and the piston are arranged in the middle of the connecting rod; the spring is sleeved at the lower end of the piston; the limiting plate is arranged at the inner lower part of the cylinder body and is provided with a guide hole, and a plurality of vent holes are distributed at the side end of the guide hole; the integral electric three-way regulating valve is connected with an outlet fluid pipe of a fluid spray pipe of the jet type vacuum pump body, and the inlet fluid pipe of the integral electric three-way regulating valve is connected with an outlet fluid pipe of high-speed input jet fluid generating equipment; the cylinder body is arranged at the side end of a lower pipeline of a pump shell of the jet vacuum pump body; the control circuit comprises a reed switch and a relay, the control circuit is arranged in an annular shell, the shell is sleeved at the outer side end of the barrel, and the switching power supply is arranged in the electric control box; the positive electrode of the control power supply output end of the control circuit, the negative power supply output end of the switching power supply and the two ends of the power supply input of the proportional-integral electric three-way regulating valve are respectively and electrically connected; the other end of the sliding adjustable resistor, the negative power output end of the switching power supply and the two signal input ends of the proportional-integral electric three-way regulating valve are respectively and electrically connected.

2. An apparatus for automatically controlling flow rate of an ejector vacuum pump according to claim 1, wherein the switching power supply is an ac to dc switching power supply module.

3. The automatic flow rate control device for an ejector vacuum pump according to claim 1, wherein the annular housing has an inner and outer structure, and an inner end of the middle portion has an annular through hole, the annular housing through hole is sleeved on an outer end of the cylinder and is in close contact with the outer end of the cylinder, the reed pipe is vertically installed on an inner side of the housing, and an outer side of the relay housing is vertically installed on an inner side of the relay housing.

4. An automatic flow rate control device for a jet vacuum pump as claimed in claim 1, wherein when the side ends of the reed switch and the magnet of the control circuit are at a nearly horizontal level, the magnetic force of the magnet acts on the reed switch, the stationary contact and the movable contact inside the reed switch are closed, one end of the reed switch is connected to the positive power input end of the relay via a wire, the other end of the reed switch is connected to the control power input end of the relay via a wire, the two ends of the power input of the relay are connected to the positive and negative poles of a light emitting diode, respectively, and a resistor is provided between the positive pole of the light emitting diode and the positive power input end of the relay.