Original solution injection pump

Abstract

This utility model discloses a stock solution injection pump, including a pump housing, a drive mechanism, and a pump piston. The pump housing has a pump inlet and a pump outlet. The pump piston is driven by the drive mechanism to move up and down in the pump housing. It also includes a limit detection mechanism, which includes an upper limit detection sensor, a lower limit detection sensor, and a detection strip. The detection strip moves up and down synchronously with the pump piston and cooperates with the upper and lower limit detection sensors. This utility model has the advantages of simple structure, good liquid flow rate accuracy control, and improved working reliability.

Description

Technical Field

[0001] This utility model relates to the field of fluid transport technology, specifically a raw liquid injection pump. Background Technology

[0002] A syringe pump is a device used to precisely control the flow rate or volume of fluids. It works by driving a piston within the housing via a drive mechanism, thereby quantitatively injecting or extracting liquid. However, in existing syringe pumps, if the drive mechanism malfunctions during piston movement, the piston's movement distance will be inaccurate, affecting the amount of liquid injected or extracted, resulting in poor flow rate control. Furthermore, if the inlet or outlet valves of the syringe pump are not fully closed or leak during the reciprocating motion of the piston, backflow of liquid can occur due to pressure changes, causing contamination. Utility Model Content

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a raw liquid injection pump with simple structure, good liquid flow rate control accuracy, and improved working reliability.

[0004] The technical solution adopted by this utility model to solve its technical problem is:

[0005] A stock solution injection pump includes a pump housing, a drive mechanism, and a pump piston. The pump housing has a pump inlet and a pump outlet. The pump piston is driven by the drive mechanism to move up and down in the pump housing. The pump piston is characterized by further including a limit detection mechanism, which includes an upper limit detection sensor, a lower limit detection sensor, and a detection strip. The detection strip moves up and down synchronously with the pump piston and cooperates with the upper limit detection sensor and the lower limit detection sensor.

[0006] The movement of the pump piston drives the raw liquid to enter the pump housing from the pump inlet and flow out from the pump outlet. During the up-and-down movement of the pump piston, the detection strip moves up and down. By cooperating with the upper limit detection sensor and the lower limit detection sensor, the detection strip monitors whether the pump piston has moved to the limit position. This can effectively prevent the impact of the drive mechanism failure on the amount of liquid extracted or injected, and ensure the accurate control of the liquid flow rate.

[0007] The pump housing of this invention is equipped with a pump inlet check valve; the pump inlet check valve can effectively prevent backflow of liquid and ensure that the original liquid is not contaminated.

[0008] The pump housing of this invention is equipped with a pump outlet check valve to further prevent liquid backflow.

[0009] The pump housing of this invention has a vertically arranged and through-hole detection groove on its side wall. The upper limit detection sensor and the lower limit detection sensor are installed on the pump housing at the position of the detection groove. The detection strip passes through the detection groove and cooperates with the upper limit detection sensor and the lower limit detection sensor.

[0010] The upper limit detection sensor and lower limit detection sensor described in this utility model are photoelectric sensors.

[0011] The drive mechanism of this utility model includes a motor, a lead screw, a connecting nut, and a guide mechanism. The motor is fixed on the pump housing. The motor shaft is connected to the lead screw that extends into the pump housing. The lead screw is threadedly connected to the connecting nut. The connecting nut is connected to the pump piston. The connecting nut and the pump piston move up and down in the pump housing via the guide mechanism to realize the up and down movement of the pump piston driven by the motor.

[0012] The guiding mechanism of this utility model includes a guide slider, and a vertically arranged guide groove is provided on the inner wall of the pump housing. The guide slider slides in cooperation with the guide groove.

[0013] The pump housing of this utility model is further provided with a pump retaining ring. The upper end of the connecting nut extends radially outward to form a connecting boss. The outer surface of the pump piston forms an upper outer section and a lower outer section along the axial direction. The outer diameter of the upper outer section is smaller than the outer diameter of the lower outer section. A horizontally set upper limit surface is formed between the upper outer section and the lower outer section. The pump retaining ring is sleeved on the upper outer section of the piston. The upper end face of the pump retaining ring abuts against the lower end face of the connecting boss. The lower end face of the pump retaining ring abuts against the upper limit surface of the pump piston.

[0014] The guide slider and the detection strip are fixed on the pump retaining ring;

[0015] The pump retaining ring, the connecting nut, and the pump piston have a simple structure and are easy to install, allowing the guide slider and the detection strip on the pump retaining ring to move up and down synchronously with the pump piston.

[0016] The pump piston of this utility model has an axially arranged upper slot, the upper part of the upper slot is open and the bottom is sealed, and the lead screw is inserted into the upper slot of the pump piston after passing through the connecting nut;

[0017] The upper slotted inner wall forms an upper inner wall section and a lower inner wall section. The inner diameter of the upper inner wall section is larger than the inner diameter of the lower inner wall section. An inner limiting surface is formed between the upper inner wall section and the lower inner wall section.

[0018] The lower end face of the connecting nut abuts against the inner limiting surface;

[0019] The bottom of the pump piston is sealed to ensure the suction and sealing of the injection pump, enabling the raw liquid to be drawn into the pump housing. The lower section of the slotted inner wall has a small inner diameter, which further ensures the stability and sealing of the piston as it moves up and down in the pump housing.

[0020] The pump housing of this invention is integrally molded; it has high structural strength, is easy to assemble, and has good sealing performance.

[0021] The beneficial effects of this utility model are as follows: the movement of the pump piston drives the raw liquid to enter the pump housing from the pump inlet and flow out from the pump outlet. During the up-and-down movement of the pump piston, the detection strip moves up and down. By cooperating with the upper limit detection sensor and the lower limit detection sensor, the detection strip monitors whether the pump piston has moved to the limit position, which can effectively prevent the impact of the drive mechanism failure on the liquid extraction or injection volume and ensure the accurate control of the liquid flow rate. The setting of the pump inlet check valve and the pump outlet check valve can effectively prevent the backflow of liquid and ensure that the raw liquid will not be contaminated. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of an injection pump.

[0023] Figure 2 This is the front view of the syringe pump.

[0024] Figure 3 yes Figure 2 Sectional view of AA.

[0025] Figure 4 yes Figure 3 Enlarged view of section B in the middle.

[0026] Figure 5 This is a schematic diagram of the hidden motor structure of an injection pump.

[0027] Appendix label: Motor-1;

[0028] Pump housing-2, detection slide groove-201, guide slide groove-202, pump inlet-203, pump outlet-204;

[0029] Connecting nut-3, connecting boss-301;

[0030] Pump piston-4, upper outer section of piston-401, lower outer section of piston-402, upper limit surface-403, upper slot-404, upper inner wall section-405, lower inner wall section-406, inner limit surface-407;

[0031] Pump retaining ring-5, detection strip-501, guide slider-502;

[0032] Lead screw-6;

[0033] Pump inlet check valve -7;

[0034] Upper limit detection sensor-801, lower limit detection sensor-802;

[0035] Raw liquid inlet pipe-901, raw liquid outlet pipe-902. Detailed Implementation

[0036] The present invention will now be described in conjunction with the accompanying drawings and embodiments.

[0037] As shown in the attached figure, a stock solution injection pump includes a pump housing 2, a drive mechanism, and a pump piston 4. The pump housing 2 has a pump inlet 203 and a pump outlet 204. The pump piston 4 is driven by the drive mechanism to move up and down in the pump housing 2. The pump also includes a limit detection mechanism, which includes an upper limit detection sensor 801, a lower limit detection sensor 802, and a detection strip 501. The detection strip 501 moves up and down synchronously with the pump piston 4 and cooperates with the upper limit detection sensor 801 and the lower limit detection sensor 802. The upper limit detection sensor 801 and the lower limit detection sensor 802 are respectively connected to a controller.

[0038] The movement of the pump piston 4 drives the raw liquid to enter the pump housing 2 from the pump inlet 203 and flow out from the pump outlet 204. During the up-and-down movement of the pump piston 4, the detection strip 501 moves up and down. The detection strip 501, together with the upper limit detection sensor 801 and the lower limit detection sensor 802, monitors whether the pump piston 4 has moved to the limit position. This can effectively prevent the impact of the drive mechanism failure on the amount of liquid extracted or injected, and ensure the accurate control of the liquid flow rate.

[0039] A pump inlet check valve 7 is installed at the pump inlet 203 of the pump housing 2, and a pump outlet check valve (not shown in the attached figure) is installed at the pump outlet 204 of the pump housing 2. The pump inlet check valve and the pump outlet check valve can effectively prevent the backflow of liquid, ensure that the original liquid will not be contaminated, and realize one-way controllable inlet and outlet.

[0040] The pump housing 2 has a vertically arranged and through-hole detection groove 201 on its side wall. The upper limit detection sensor 801 and the lower limit detection sensor 802 are installed on the pump housing 2 at the position of the detection groove 201. In this embodiment, the upper limit detection sensor 801 is located above the lower limit detection sensor 802. The detection strip 501 passes through the detection groove 201 and cooperates with the upper limit detection sensor 801 and the lower limit detection sensor 802.

[0041] In this embodiment, the upper limit detection sensor 801 and the lower limit detection sensor 802 are photoelectric sensors, and the detection strip is inductively coordinated with the upper limit detection sensor 801 and the lower limit detection sensor 802.

[0042] The driving mechanism includes a motor 1, a lead screw 6, a connecting nut 3, and a guiding mechanism. The motor 1 is fixed to the pump housing 2. In this embodiment, the motor 1 is fixed to the top of the pump housing 2. A through hole is provided on the top of the pump housing for the motor shaft to pass through. The pump inlet 203 is located at the bottom of the pump housing 2, and the pump outlet 204 is located on the bottom side wall of the pump housing 2. The motor shaft of the motor 1 passes through the through hole at the top of the pump housing and is connected to the lead screw 6, which extends into the pump housing 2. The lead screw 6 is threadedly connected to the connecting nut 3. The connecting nut 3 is connected to the pump piston 4. The connecting nut 3 and the pump piston 4 move up and down in the pump housing 2 via the guiding mechanism to realize the up and down movement of the pump piston 4 driven by the motor 1.

[0043] The guiding mechanism includes a guide slider 502, and a vertically arranged guide groove 202 is provided on the inner wall of the pump housing 3. The guide slider 502 and the guide groove 202 are slidably engaged.

[0044] In this embodiment, the pump piston 4 has an axially oriented upper slot 404. The upper slot 404 is open at the top and sealed at the bottom. The pump piston 4 is fixedly sleeved on the connecting nut 3 through the upper slot 404. The lead screw 6 passes through the connecting nut 3 and is inserted into the upper slot 404 of the pump piston 4. The bottom of the pump piston 4 is sealed to ensure the suction and sealing of the injection pump, and to draw the original liquid into the pump housing 2.

[0045] The inner wall of the upper slot 404 forms an upper inner wall section 405 and a lower inner wall section 406. The inner diameter of the upper inner wall section 405 is larger than the inner diameter of the lower inner wall section 406. An inner limiting surface 407 is formed between the upper inner wall section 405 and the lower inner wall section 406.

[0046] The lower end face of the connecting nut 3 abuts against the inner limiting surface 407;

[0047] The smaller inner diameter of the lower section of the 404 inner wall with the upper slot further ensures the stability and sealing of the pump piston as it moves up and down within the pump housing.

[0048] The pump piston 4 is sealed to the inner wall of the pump housing 2.

[0049] The pump housing 2 is also provided with a pump retaining ring 5. The upper end of the connecting nut 3 extends radially outward to form a connecting boss 301. The outer surface of the pump piston 4 forms an upper outer section 401 and a lower outer section 402 along the axial direction. The outer diameter of the upper outer section 401 is smaller than the outer diameter of the lower outer section 402. A horizontally set upper limit surface 403 is formed between the upper outer section 401 and the lower outer section 402. The pump retaining ring 5 is sleeved on the upper outer section 401. The upper end face of the pump retaining ring 5 and the upper end face of the upper outer section 401 abut against the lower end face of the connecting boss 301. The lower end face of the pump retaining ring 5 abuts against the upper limit surface 403 of the pump piston 4.

[0050] The guide slider 502 and the detection strip 501 are fixed on the pump retaining ring 5. In this embodiment, the detection groove 201 and the guide groove 202 are arranged opposite to each other on the pump housing 2, and the detection strip 501 and the guide slider 502 are respectively fixed on opposite sides of the pump retaining ring 5. The pump retaining ring 5, the connecting nut 3 and the pump piston 4 are well-matched, with a simple structure and convenient installation, so that the guide slider 202 and the detection strip 501 on the pump retaining ring 5 can move up and down synchronously with the pump piston 4.

[0051] The pump housing 2 is integrally formed; it has high structural strength, is easy to assemble, and has good sealing performance.

[0052] In this embodiment, a raw liquid inlet pipe 901 is connected to the pump inlet check valve, and a raw liquid outlet pipe 902 is connected to the pump outlet.

[0053] In this embodiment, the controller is either an MCU-based controller or a PLC controller.

[0054] When using this utility model:

[0055] The controller controls motor 1 to operate. The forward rotation of motor 1 drives lead screw 6 to rotate forward, which in turn moves connecting nut 3 upward within pump housing 2, drawing the raw liquid into the pump housing 2 along the raw liquid inlet pipe 901 and the pump inlet check valve 7. Conversely, the controller controls motor 1 to rotate in the reverse direction, driving lead screw 6 to rotate in the reverse direction, which in turn moves connecting nut 3 downward within pump housing 2, pushing the raw liquid out of pump outlet 204 and raw liquid outlet pipe 902. During this process, detection strip 501 moves up and down with pump piston 4. When detection strip 501 moves downward, it reaches the lower limit detection sensor 802 position. When the lower limit detection sensor 802 senses the detection strip 501, it feeds a signal back to the controller. When the detection strip 501 moves upward to reach the position of the upper limit detection sensor 801, the upper limit detection sensor 801 senses the detection strip 501 and feeds a signal back to the controller. When the detection strip 501 moves to the position of either the lower limit detection sensor 802 or the upper limit detection sensor 801, it indicates that there are problems such as motor stepping inaccuracy, encoder failure, or drive circuit issues. The controller then stops the motor to prevent the amount of raw liquid delivered from not meeting the requirements.

Claims

1. A stock solution injection pump, comprising a pump housing, a drive mechanism, and a pump piston, wherein the pump housing has a pump inlet and a pump outlet, and the pump piston is driven by the drive mechanism to move up and down within the pump housing, characterized in that: It also includes a limit detection mechanism, which includes an upper limit detection sensor, a lower limit detection sensor, and a detection bar. The detection bar moves up and down synchronously with the pump piston and cooperates with the upper limit detection sensor and the lower limit detection sensor.

2. The stock solution injection pump according to claim 1, characterized in that: A pump inlet check valve is installed at the pump inlet of the pump housing.

3. A stock solution injection pump according to claim 1 or 2, characterized in that: A pump outlet check valve is installed at the pump outlet of the pump housing.

4. A stock solution injection pump according to claim 1 or 2, characterized in that: The pump housing has a vertically arranged and through-hole detection groove on its side wall. The upper limit detection sensor and the lower limit detection sensor are installed on the pump housing at the position of the detection groove. The detection strip passes through the detection groove and cooperates with the upper limit detection sensor and the lower limit detection sensor.

5. A stock solution injection pump according to claim 4, characterized in that: The upper limit detection sensor and the lower limit detection sensor are photoelectric sensors.

6. A stock solution injection pump according to claim 1, 2, or 5, characterized in that: The drive mechanism includes a motor, a lead screw, a connecting nut, and a guide mechanism. The motor is fixed on the pump housing. The motor shaft is connected to the lead screw that extends into the pump housing. The lead screw is threadedly connected to the connecting nut. The connecting nut is connected to the pump piston. The connecting nut and the pump piston move up and down in the pump housing via the guide mechanism.

7. A stock solution injection pump according to claim 6, characterized in that: The guiding mechanism includes a guide slider, and a vertically arranged guide groove is provided on the inner wall of the pump housing. The guide slider slides in cooperation with the guide groove.

8. A stock solution injection pump according to claim 6, characterized in that: The pump housing is also provided with a pump retaining ring. The upper end of the connecting nut extends radially outward to form a connecting boss. The outer surface of the pump piston forms an upper outer section and a lower outer section along the axial direction. The outer diameter of the upper outer section is smaller than the outer diameter of the lower outer section. A horizontally set upper limit surface is formed between the upper outer section and the lower outer section. The pump retaining ring is fitted on the upper outer section of the piston. The upper end face of the pump retaining ring abuts against the lower end face of the connecting boss. The lower end face of the pump retaining ring abuts against the upper limit surface of the pump piston. The guide slider and the detection strip are fixed on the pump retaining ring.

9. A stock solution injection pump according to claim 8, characterized in that: The pump piston has an axially oriented upper slot, which is open at the top and sealed at the bottom. The lead screw passes through the connecting nut and is inserted into the upper slot of the pump piston. The upper slotted inner wall forms an upper inner wall section and a lower inner wall section. The inner diameter of the upper inner wall section is larger than the inner diameter of the lower inner wall section. An inner limiting surface is formed between the upper inner wall section and the lower inner wall section. The lower end face of the connecting nut abuts against the inner limiting surface.

10. A stock solution injection pump according to claim 1, 2, 5, 7, 8, or 9, characterized in that: The pump housing is integrally molded.

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