Constant-flow injection pump and reversing valve thereof

Abstract

The invention discloses a constant-flow injection pump and a reversing valve thereof, and relates to the technical field of injection pumps, the constant-flow injection pump comprises two injectors and two sets of driving assemblies; the injectors correspond to the driving assemblies one to one; the output end of the driving assembly drives the piston rod of the injector to move along the sleeve; the injector further comprises the reversing valve, and the liquid ports of the two injectors are connected to the head end ports of the two injection channels on the same reversing valve respectively. The volume can be reduced, the product cost is reduced, and continuous transmission of liquid is realized through the electronic control execution device.

Description

Technical Field

[0001] The present invention belongs to the technical field of injection pumps, and particularly relates to a constant-flow injection pump and a reversing valve thereof. Background Art

[0002] An injection pump is a volumetric pump mainly used for the distribution or transportation of fluids, and is widely used in industries such as food and chemical industries. When using an injection pump to transfer a liquid, the syringe makes a reciprocating suction and push movement, and at the same time, the reversing valve changes direction to cooperate with the syringe to complete the liquid transfer.

[0003] When the injection pump needs to continuously transfer a liquid without interruption, using a single injection pump alone cannot meet the requirement. When an injection pump is sucking liquid, it cannot discharge liquid, resulting in an interruption in the transferred liquid. The realization of constant-flow injection utilizes two injection pumps and two reversing valves, but it has a large volume and high cost. There is an urgent need for a constant-flow injection pump with a small volume and low cost to fill the gap and be applied in industrial production supporting. Summary of the Invention

[0004] The purpose of the present invention is to provide a constant-flow injection pump and a reversing valve thereof in view of the defects and deficiencies of the prior art. It can replace the functions of two cooperating reversing valves, can install two syringes, is driven by one motor, reduces the volume, lowers the product cost, and realizes the continuous transfer of liquid through an electronic control execution device.

[0005] The present invention is realized through the following technical solutions:

[0006] A novel reversing valve includes a valve body and a valve core, and the valve core is installed on the valve body; a channel A and a channel B are provided on the lower surface of the valve core; channels aa, ab, ba, bb, injection channel C, and injection channel D are provided inside the valve body;

[0007] Among them, the head end port of channel aa is the liquid inlet, and the head end port of channel ba is connected to the tail end port of channel aa; the head end port of channel bb is used as the liquid outlet, and the head end port of channel ab is connected to the tail end port of channel bb;

[0008] The tail end ports of the six channels aa, ab, ba, bb, injection channel C, and injection channel D are all arc-shaped slots provided on the upper surface of the valve body;

[0009] Both ends of channel A and channel B are respectively connected to the corresponding arc-shaped slots.

[0010] Furthermore, it includes a valve body and a valve core, and the valve core is installed in the valve body; characterized in that the tail end ports of the four channels aa, ab, ba, and bb are all located in the peripheral area of the upper surface of the valve body, and the tail end ports of the two injection channels C and D are located in the central area of the upper surface of the valve body.

[0011] Furthermore, the channel A corresponds to channels aa and bb, and the channel B corresponds to channels ba and bb; as the relative rotation angle between the valve core and the valve body increases, the following four states exist:

[0012] First state: The injection channels C and D are simultaneously extracted. The injection channel C, channel A, and channel aa are sequentially connected. The injection channel D, channel B, channel ba, and channel aa are sequentially connected.

[0013] Second state: The injection channel C is extracted and the injection channel D is discharged. The injection channel C, channel A, and channel aa are sequentially connected. The injection channel D, channel B, and channel bb are sequentially connected.

[0014] Third state: The injection channels C and D are simultaneously discharged. The injection channel C, channel A, channel ab, and channel bb are sequentially connected. The injection channel D, channel B, and channel bb are sequentially connected.

[0015] Fourth state: The injection channel C is discharged and the injection channel D is extracted. The injection channel C, channel A, channel ab, and channel bb are sequentially connected. The injection channel D, channel B, channel ba, and channel aa are sequentially connected.

[0016] Furthermore, the channels A and B are slots on the lower surface of the valve core. The channel A is a straight slot extending from the center position of the valve core to the outside of the valve core. The channel B is a three-fork slot, where the two forks of the three-fork slot face the outside of the valve core.

[0017] Furthermore, an annular positioning groove is formed on the upper surface of the valve body, and the valve core is installed in the annular positioning groove. The end ports of the channels aa, ab, ba, bb, the injection channel C, and the injection channel D are all located within the area surrounded by the annular positioning groove.

[0018] Furthermore, the three-fork slots of the channel B are respectively fork m, fork l, and fork n. The end of fork n is connected to the end port of the injection channel D. The end of fork l is normally closed in the first, second, and third states and is connected to the end port of the channel ba in the fourth state. The end of fork m is connected to the end port of the channel ba and the end port of the channel bb at different rotation angles of the valve core and the valve body.

[0019] A new type of constant flow injection pump includes two syringes and two sets of driving components; the syringes and the driving components are in one-to-one correspondence; the output end of the driving component drives the piston rod of the syringe to move along its sleeve; it also includes a reversing valve as described above, and the liquid ports of the two syringes are respectively connected to the first end ports of the two injection channels on the same reversing valve.

[0020] Further, it further includes a driving front case; behind the driving front case, there are two parallel support plates, and the support plates are perpendicular to the driving front case; two sets of driving components are respectively installed on the corresponding support plates, and two syringes and a reversing valve are all installed in front of the driving front case.

[0021] Further, the driving component includes a driving motor and a lead screw pair. The driving motor is installed on the corresponding support plate; both ends of the lead screw of the lead screw pair are connected to the support plate by bearings, and the driving motor drives the rotation of the lead screw of the lead screw pair; the nut of the lead screw pair passes through the driving front case and is connected to the piston rod of the syringe, and the nut drives the piston rod to perform a linear motion in the sleeve of the syringe; after the working state is stable, the sum of the output flows of the two syringes remains constant.

[0022] Further, the driving component further includes a synchronous pulley set; the driving motor drives the rotation of the nut of the lead screw pair through the synchronous pulley set; the reversing motor of the reversing valve is installed on the back of the driving front case, and its output end penetrates through the driving front case and is connected to the valve body of the reversing valve.

[0023] Compared with the prior art, the beneficial effects of the present invention are:

[0024] Compared with the prior art that one motor can only drive one reversing valve and only one syringe can be installed on the reversing valve, this reversing valve can install two syringes simultaneously and is driven by one reversing motor, which can not only reduce the volume but also reduce the product cost. Description of the Drawings

[0025] Figure 1 is the overall structure explosion diagram of the reversing valve of the present invention;

[0026] Figure 2 is the schematic diagram of the lower surface of the reversing valve spool of the present invention;

[0027] Figure 3 is the schematic diagram of the lower surface of the reversing valve body of the present invention;

[0028] Figure 4 is the schematic diagram of the internal channel of the reversing valve body of the present invention;

[0029] Figure 5 is the schematic diagram of the position of the end port of the reversing valve body of the present invention;

[0030] Figure 6 is the schematic diagram of the channel connection in the first state of the reversing valve of the present invention;

[0031] Figure 7 is the schematic diagram of the channel connection in the second state of the reversing valve of the present invention;

[0032] Figure 8 is the schematic diagram of the channel connection in the third state of the reversing valve of the present invention;

[0033] Figure 9 It is a schematic diagram of the channel connection in the four - level state of the reversing valve of the present invention;

[0034] Figure 10 It is a schematic diagram of the application principle of the reversing valve of the present invention;

[0035] Figure 11 It is a three - dimensional structure schematic diagram of the constant - flow injection pump of the present invention;

[0036] Figure 12 It is an internal structure schematic diagram of the constant - flow injection pump of the present invention;

[0037] Figure 13 It is a rear - structure schematic diagram of the drive housing of the present invention.

[0038] In the figure: 1. Wave - shaped spring, 2. Flat thrust bearing, 3. Spool positioning block, 4. Spool, 5. O - ring, 6. Valve body, 7. PTFE ball, 8. Spool mounting block, 4 - 1. Channel A, 4 - 2. Channel B, 6 - 1. Channel aa, 6 - 2. Channel ab, 6 - 3. Channel ba, 6 - 4. Channel bb, 6 - 5. Annular positioning groove, 6 - 6. Injection channel D, 6 - 7. Injection channel C, 6 - 1 - 1. End port of channel aa, 6 - 2 - 2. End port of channel ab.

[0039] 6 - 3 - 3. End port of channel ba, 6 - 4 - 4. End port of channel bb, 6 - 5 - 5. Annular positioning groove, 6 - 6 - 6. End port of injection channel D, 6 - 7 - 7. End port of injection channel C, 10. Reversing valve, 20. Front drive housing, 30. Syringe C, 40. Syringe D, 50. Reversing motor, 60. Actuator C, 70. Actuator D, 80. Lead screw, 90. Nut, 100. Drive motor. Detailed implementation manners

[0040] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0041] Refer to Figures 11 to 13 , this embodiment provides a constant - flow injection pump, which includes an actuator C, an actuator D, a syringe C, a syringe D and a reversing valve; the continuous transmission of liquid is realized by electronically controlling the actuator. Since the syringe is detachable, syringes of different specifications can be replaced to achieve precise liquid transmission within different ranges.

[0042] In this embodiment, the actuating device includes a driving motor and a lead screw pair: the driving motor drives the ball screw of the lead screw pair to rotate, and the ball screw drives the piston rod of the syringe to reciprocate up and down through the nut connected with the thread.

[0043] The support body of the constant flow injection pump is a driving front shell and two parallel support plates installed behind the driving front shell; both support plates are perpendicular to the driving front shell.

[0044] Two syringes and a reversing valve are installed in front of the driving front shell, and the valve body of the reversing valve and the sleeve of the syringe are fixedly connected to the driving front shell. The driving motor in the actuating assembly is located between the two support plates and is respectively installed on the corresponding support plates.

[0045] Both ends of the ball screw are respectively connected to the support plate through bearings. One motor drives one ball screw to rotate. The nut is threadedly connected to the corresponding ball screw (lead screw) and is constrained in the long circular hole of the driving front shell. The end of the piston rod of the syringe is connected to the nut. The click drives the ball screw to rotate through a belt.

[0046] A reversing motor is also installed behind the driving front shell. The driving end of the reversing motor penetrates through the driving front shell and is connected to the valve core of the reversing valve, driving the valve core to rotate around its own central axis. The liquid ports of the two syringes are respectively connected to the interfaces of the injection channel C and the injection channel D of the reversing valve.

[0047] The constant flow working process of this embodiment:

[0048] A. After starting, the valve core of the reversing valve rotates, so that syringe C and syringe D are in the extraction state. The actuating device C drives syringe C, and the actuating device D drives syringe D to start extracting liquid at the same time. After extraction is completed, the reversing valve switches, so that syringe C and syringe D are in the output state;

[0049] B. The actuating device C drives syringe C, and syringe C reaches the set speed with a large acceleration;

[0050] C. After running at a constant speed for a period of time, syringe C starts to decelerate, and at the same time, syringe D starts to accelerate with the same acceleration; when syringe C finishes decelerating, syringe D finishes accelerating and starts to run at a constant speed;

[0051] D. After syringe C finishes decelerating, the reversing valve rotates, so that syringe C is in the extraction state. Then syringe C extracts liquid. After extraction is completed, the reversing valve rotates, and syringe C switches to the output state and waits; during this process, syringe D is always in the output state

[0052] E. After syringe D finishes running at a constant speed, it starts to decelerate, and at the same time, syringe C starts to accelerate with the same acceleration.

[0053] Repeat this cycle. The reversing valve switches, and the two syringes cooperate with each other to achieve constant flow transmission.

[0054] Refer to Figure 1 , which is the reversing valve adopted in this embodiment. It includes a valve body 6, a valve core 4, a valve core positioning block 3, a valve core mounting block 8, a flat thrust bearing 2, a corrugated spring 1, an O-ring 5, and a polytetrafluoroethylene ball (PTFE ball) 7.

[0055] The valve body and the valve core are installed together, and they have relative rotational freedom; the polytetrafluoroethylene ball is installed on the valve body. The valve core positioning block is installed in the valve core mounting hole, and the flat thrust ball bearing and the corrugated spring are installed on the valve core in sequence. The valve core mounting block compresses the corrugated spring to make the flat thrust bearing, so that the valve core tightly adheres to the valve body. The valve core mounting block is locked on the valve body by an inner hexagon socket head cap screw. An O-ring is installed on the valve core to ensure the seal between the valve core and the valve body.

[0056] Specifically refer to Figure 2 , channels A and B are provided on the upper and lower surfaces of the valve core. Among them, channel A is a straight line type, specifically a slot across the outer peripheral area and the central area of the valve body. Channel B is a three-fork slot, and the three-fork slot is fork m, fork l, and fork n. Among them, the end of fork n is located above the central area of the valve body; the ends of fork l and fork m are both located above the outer peripheral area of the valve body.

[0057] Specifically refer to Figure 4 , four interfaces are provided on the valve body. Two of the interfaces are externally connected for liquid output or input, and the other two interfaces are used to connect the syringes. The liquid output interface is the head port of channel bb, and the head port of channel ab is connected to the end port of channel bb; the liquid input interface is the head port of channel aa, and channel ba is connected to the end port of aa. In this embodiment, the end ports of channels aa, ab, ba, bb, injection channel C, and injection channel D are all arc-shaped slots on the upper surface of the valve body. Both syringe channel C and syringe channel D can achieve two liquid flow directions of liquid input and output.

[0058] Refer to Figure 3 and refer to Figure 5 , on the upper surface of the valve body, within the area surrounded by the annular positioning groove, a plurality of arc-shaped slots are provided; among them, the two arc-shaped slots located in the central area are the inner flow ports of injection channel C and the end ports of injection channel D respectively, and the four arc-shaped slots located in the outer peripheral area are the end ports of channel aa, the end ports of channel ab, the end ports of channel ba, and the end ports of channel bb in sequence and adjacent to each other.

[0059] In this embodiment, the end ports of injection channel C and injection channel D are located on the first circumference, and the end ports of channel aa, channel ab, channel ba, and channel bb are located on the second circumference, and the diameter of the second circumference is greater than that of the first circumference.

[0060] Based on the relative rotation of the valve body and the valve core, different channels are connected. As the relative rotation angle between the valve core and the valve body increases, there are the following four states:

[0061] Refer to Figure 6 , the first-level state, injection channel C and injection channel D draw liquid simultaneously: injection channel C, channel A, and channel aa are connected in sequence, and injection channel D, channel B, channel ba, and channel aa are connected in sequence; the liquid can enter from the head port of channel aa and branch at the end port of channel aa and then reach the two syringes.

[0062] Refer to Figure 7 , the second-level state: injection channel C draws liquid and injection channel D discharges liquid. Injection channel C, channel A, and channel aa are connected in sequence, and injection channel D, channel B, and channel bb are connected in sequence; the liquid can enter syringe C from channel aa, and the liquid in syringe D can be discharged through channel bb.

[0063] Refer to Figure 8 , the third-level state: injection channel C and injection channel D discharge simultaneously. Injection channel C, channel A, channel ab, and channel bb are connected in sequence, and injection channel D, channel B, and channel bb are connected in sequence; the liquid in the two syringes is discharged through the head port of channel bb.

[0064] Refer to Figure 9 , the fourth-level state: injection channel C discharges and injection channel D draws. Injection channel C, channel A, channel ab, and channel bb are connected in sequence, and injection channel D, channel B, channel ba, and channel aa are connected in sequence. The liquid can enter syringe D from channel aa, and the liquid in syringe C can be discharged through channel bb.

[0065] In the above states, the forked n end of channel B is connected to the end port of injection channel D. The forked l end is normally closed in the first-level, second-level, and third-level states and is connected to the end port of channel ba in the fourth-level state; the forked m end is connected to the end port of channel ba in the first-level state and is connected to the end port of channel bb in the second and third levels.

[0066] In this embodiment, the forked l of channel B has an arc segment, and the arc slot length of channel ba is less than the lengths of the other three channels on the same circumference.

[0067] Through the setting of the rotation angles of the above four states and the setting of the rotation timing sequence, continuous injection can be achieved by using two syringes and a reversing valve. Refer to Figure 10 , during the adjustment of the reversing valve by the motor and the adjustment of the syringe speed of the syringe, continuous and stable liquid output can be achieved.

[0068] It should be noted that the above is only a preferred application example of the present invention and is not intended to limit the protection scope of the present invention. All technical solutions adopting equivalent replacement or equivalent transformation forms are within the protection scope of the present invention.

Claims

1. A new type of reversing valve, comprising a valve body and a valve core, wherein the valve core is mounted on the valve body; characterized in that: The lower surface of the valve core is provided with a channel A and a channel B; the interior of the valve body is provided with a channel aa, a channel ab, a channel ba, a channel bb and an injection channel C and an injection channel D; Among them, the first end port of channel aa is the liquid inlet, and the first end port of channel ba is connected to the end port of channel aa; the first end port of channel bb is the liquid outlet, and the first end port of channel ab is connected to the end port of channel bb; The end ports of the six channels aa, ab, ba, bb, injection channel C and injection channel D are all arc-shaped slots arranged on the upper surface of the valve body; Both ends of channel A and channel B are connected to corresponding arc-shaped slots respectively.

2. A new type of reversing valve according to claim 1, characterized in that: It includes a valve body and a valve core, and the valve core is installed in the valve body; it is characterized in that the end ports of the four channels aa, ab, ba and bb are all located in the peripheral area of ​​the upper surface of the valve body, and the end ports of the injection channel C and the injection channel D are located in the central area of ​​the upper surface of the valve body.

3. A new type of reversing valve according to claim 1, characterized in that: The channel A corresponds to the channel aa and the channel ab, and the channel B corresponds to the channel ba and the channel bb; as the relative rotation angle between the valve core and the valve body increases, there are the following four states: In the primary state, injection channel C and injection channel D are extracted simultaneously, injection channel C, channel A and channel aa are connected in sequence, and injection channel D, channel B, channel ba and channel aa are connected in sequence; Secondary state: injection channel C draws and injection channel D discharges, injection channel C, channel A and channel aa are connected in sequence, and injection channel D, channel B and channel bb are connected in sequence; Level 3 state: injection channel C and injection channel D are discharged simultaneously, injection channel C, channel A, channel ab, channel bb are connected in sequence, and injection channel D, channel B and channel bb are connected in sequence; Level 4 state: injection channel C discharges and injection channel D draws, injection channel C, channel A, channel ab, and channel bb are connected in sequence, and injection channel D, channel B, channel ba, and channel aa are connected in sequence.

4. A new type of reversing valve according to claim 1, characterized in that: The channel A and the channel B are both grooves on the lower surface of the valve core; the channel A is a linear groove extending from the center position of the valve core to the outside of the valve core; the channel B is a three-forked groove, wherein the two forks of the three-forked groove face the outside of the valve core.

5. A new type of reversing valve according to claim 1, characterized in that: An annular positioning groove is provided on the upper surface of the valve body, and the valve core is installed in the annular positioning groove; the end ports of channels aa, ab, ba, bb, injection channel C and injection channel D are all located in the area surrounded by the annular positioning groove.

6. A new type of reversing valve according to claim 4, characterized in that: The three-fork grooves of the channel B are fork m, fork l and fork n, wherein the end of fork n is connected to the end port of the injection channel D, the end of fork l is normally closed in the first state, the second state and the third state, and is connected to the end port of the channel ba in the fourth state; the end of fork m is connected to the end port of the channel ba and the end port of the channel bb at different rotation angles of the valve core and the valve body.

7. A novel constant current injection pump, comprising two syringes and two sets of drive assemblies; the syringes and the drive assemblies correspond one to one; the output end of the drive assembly drives the piston rod of the syringe to move along its sleeve; characterized in that: It also includes the reversing valve according to any one of claims 1 to 6, wherein the liquid ports of the two syringes are respectively connected to the head end ports of the two injection channels on the same reversing valve.

8. A novel constant current injection pump according to claim 7, characterized in that: It also includes a driving front shell; two parallel support plates are arranged at the rear of the driving front shell, and the support plates are perpendicular to the driving front shell; two groups of driving components are respectively installed on the corresponding support plates, and two syringes and the reversing valve are installed in front of the driving front shell.

9. A novel constant current injection pump according to claim 8, characterized in that: The driving assembly includes a driving motor and a screw pair, the driving motor is installed on the corresponding support plate; both ends of the screw of the screw pair are connected to the support plate bearings, and the driving motor drives the screw of the screw pair to rotate; the nut of the screw pair passes through the driving front shell and is connected to the piston rod of the syringe, and the nut drives the piston rod to make a linear motion in the sleeve of the syringe; after the working state is stable, the sum of the output flow rates of the two syringes remains constant.

10. A novel constant current injection pump according to claim 9, characterized in that: The driving assembly also includes a synchronous pulley group; the driving motor drives the nut of the lead screw pair to rotate through the synchronous pulley group; the reversing motor of the reversing valve is installed on the back of the driving front shell, and its output end passes through the driving front shell and is connected to the valve body of the reversing valve.

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