Injection pump

Abstract

The utility model discloses an injection pump which comprises a controller, a first driving motor, a second driving motor, a rotary transmission component, a linear transmission component, a sample injector and a rotary valve, the first driving motor can be controlled by the controller to drive the push rod of the sample injector to do reciprocating motion through the rotary transmission assembly and the linear transmission assembly, so as to suck fluid into the sample injector or discharge the fluid out of the sample injector; the second driving motor can be controlled by the controller to switch a fluid inlet and / or a fluid outlet of the sample injector through the rotary valve; the rotary transmission assembly comprises a first synchronous wheel connected to the output end of the first driving motor and a second synchronous wheel in transmission connection with the first synchronous wheel, the second synchronous wheel is connected with the linear transmission assembly so as to convert rotary driving force of the first driving motor into linear driving force, and the diameter of the first synchronous wheel is smaller than that of the second synchronous wheel. In this way, the low-speed torque increasing function is achieved, and the flow of fluid sucked or discharged by the injection pump can be accurately controlled.

Description

Technical Field

[0001] This utility model belongs to the technical field of precision fluid control equipment, specifically relating to an injection pump. Background Technology

[0002] Laboratory precision syringe pumps are high-precision flow control devices widely used in various research fields, including pharmaceutical, chemical, biological, food science, mass spectrometry, and microfluidics. For example, in pharmaceutical research, precision syringe pumps are used to accurately deliver drugs, conduct pharmacokinetic and pharmacodynamic studies, and precisely control the addition of drug components during drug formulation and preparation. In mass spectrometry, syringe pumps are used to precisely control sample introduction to obtain high-quality analytical results. In the biological field, syringe pumps are used in cell culture, tissue engineering, and biochemical experiments to precisely control the delivery of bioactive substances.

[0003] As can be seen, for the syringe pumps used in the examples above, excellent positioning capabilities and stability are required to achieve precise control of the injection flow rate. However, commercially available syringe pumps generally suffer from low accuracy and cannot meet the needs of various applications.

[0004] The information disclosed in this background section is intended only to enhance the understanding of the overall background of this utility model and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Utility Model Content

[0005] The purpose of this invention is to provide an injection pump that can solve the problem of low precision in existing injection pumps.

[0006] To achieve the above objectives, the technical solution provided by a specific embodiment of this utility model is as follows:

[0007] An injection pump includes a controller, a first drive motor, a second drive motor, a rotary transmission assembly, a linear transmission assembly, an injector, and a rotary valve.

[0008] The first drive motor can be controlled by a controller to drive the push rod of the injector to reciprocate through a rotary transmission assembly and a linear transmission assembly, thereby drawing fluid into the injector or expelling fluid from the injector.

[0009] The second drive motor can be controlled by the controller to switch the fluid inlet and / or fluid outlet of the injector via a rotary valve;

[0010] The rotary transmission assembly includes a first synchronous pulley connected to the output end of the first drive motor and a second synchronous pulley that is drively connected to the first synchronous pulley. The second synchronous pulley is connected to a linear transmission assembly to convert the rotary driving force of the first drive motor into a linear driving force. The diameter of the first synchronous pulley is smaller than the diameter of the second synchronous pulley.

[0011] In one or more embodiments of this utility model, the ratio of the diameter of the first synchronous pulley to the diameter of the second synchronous pulley is between 1:1.5 and 1:2.5.

[0012] In one or more embodiments of this utility model, the diameter ratio of the first synchronous pulley to the diameter of the second synchronous pulley is 1:2.1.

[0013] In one or more embodiments of the present invention, the rotary transmission assembly further includes a transmission belt fitted on the first synchronous pulley and the second synchronous pulley, wherein the first synchronous pulley and the transmission belt, as well as the second synchronous pulley and the transmission belt, are connected by positioning protrusions and positioning grooves that can mesh with each other.

[0014] In one or more embodiments of this utility model, the linear transmission assembly includes a lead screw and a nut fitted on the lead screw, the lead screw being parallel to the output shaft of the first drive motor, and the nut being connected to the push rod of the sampler via a connecting member;

[0015] The injection pump also includes a guide shaft parallel to the lead screw, and the connector is slidably fitted onto the guide shaft.

[0016] In one or more embodiments of the present invention, the push rod and the lead screw of the injector are arranged parallel to each other at intervals, and the connector includes a horizontal connecting arm located between the push rod and the lead screw of the injector, the horizontal connecting arm having a first position at the bottom end and a second position at the top end;

[0017] When the horizontal connecting arm is in the first position, the push rod of the injector is in the maximum tension state;

[0018] When the horizontal connecting arm is in the second position, the push rod of the injector is in the maximum advance state.

[0019] In one or more embodiments of the present invention, the injection pump further includes a proximity sensor mounted on a first drive motor, the proximity sensor being used to detect the position of the nut to determine the zero point position of the injector.

[0020] In one or more embodiments of the present invention, the injection pump includes a first encoder for monitoring the rotation angle of a first drive motor, and the controller is used to compare the rotation pulses controlling the rotation of the first drive motor with the feedback pulses of the first encoder to perform rotation pulse compensation on the first drive motor.

[0021] In one or more embodiments of the present invention, the injection pump includes a second encoder for monitoring the rotation angle of a second drive motor, and the controller is used to compare the rotation pulses controlling the rotation of the second drive motor and the feedback pulses of the second encoder to perform rotation pulse compensation on the second drive motor.

[0022] In one or more embodiments of the present invention, the injection pump further includes a coupling connecting the output shaft of the second drive motor and the rotary valve.

[0023] In one or more embodiments of the present invention, the injection pump further includes a communication module for communicating with external devices, wherein the communication module is RS485 and / or CANopen.

[0024] Compared with the prior art, the injection pump of this utility model drives the push rod of the injector to reciprocate through a first drive motor, a rotary transmission assembly, and a linear transmission assembly. The second drive motor can switch the fluid inlet and / or fluid outlet of the injector through a rotary valve, thereby realizing the intake or discharge of fluid into the injector. In this process, since the rotary transmission assembly includes a first synchronous wheel and a second synchronous wheel connected by transmission, the first synchronous wheel is connected to the output end of the first drive motor, and the second synchronous wheel is connected to the linear transmission assembly, thereby converting the rotary driving force of the first drive motor into a linear driving force. Furthermore, the diameter of the first synchronous wheel is set to be smaller than that of the second synchronous wheel, that is, using the directly driven "small wheel" as the driving wheel and the transmission-connected "large wheel" as the driven wheel, the function of low-speed torque increase is realized, making the kinetic energy transmission more stable and reliable, thereby realizing precise control of the flow rate of fluid intake or discharge of the injection pump. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the structure of the injection pump in one embodiment of the present invention;

[0027] Figure 2Combined structural diagram of the first drive motor and the first synchronous pulley of the syringe pump in an embodiment of the present utility model;

[0028] Figure 3 Combined structural diagram of the first drive motor, the rotary transmission component and the linear transmission component of the syringe pump in an embodiment of the present utility model;

[0029] Figure 4 Combined structural diagram of the linear transmission component and the sampler of the syringe pump in an embodiment of the present utility model;

[0030] Figure 5 Combined structural diagram of the second drive motor and the rotary valve of the syringe pump in an embodiment of the present utility model;

[0031] Figure 6 Schematic structural diagram of the rotary transmission component of the syringe pump in an embodiment of the present utility model. Detailed implementation manners

[0032] In order to enable those skilled in the art to better understand the technical solutions in the present utility model, the technical solutions in the embodiments of the present utility model will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without making creative efforts shall fall within the protection scope of the present utility model.

[0033] Refer Figure 1 , the syringe pump 100 of an embodiment of the present utility model is introduced, which includes a controller 11, a first drive motor 20, a second drive motor 30, a rotary transmission component 40, a linear transmission component 50, a sampler 60 and a rotary valve 70.

[0034] With reference to Figure 2 and Figure 5 , the first drive motor 20 can be controlled by the controller 11 to drive the push rod 61 of the sampler 60 to reciprocate through the rotary transmission component 40 and the linear transmission component 50, so as to suck fluid into the sampler 60 or discharge the fluid out of the sampler 60. The second drive motor 30 can be controlled by the controller 11 to switch the fluid inlet and / or fluid outlet of the sampler 60 through the rotary valve 70.

[0035] With reference to Figure 2 and Figure 3Specifically, the rotary transmission assembly 40 includes a first synchronous pulley 41 connected to the output end of the first drive motor 20, and a second synchronous pulley 42 driven by the first synchronous pulley 41. The second synchronous pulley 42 is connected to the linear transmission assembly 50 to convert the rotary driving force of the first drive motor 20 into a linear driving force. It can be seen that the first synchronous pulley 41 is essentially the driving pulley directly connected to the first drive motor 20, while the second synchronous pulley 42 is the driven pulley indirectly driven by the first synchronous pulley 41. The linear transmission assembly 50 includes a lead screw 51 and a nut 52 fitted onto the lead screw 51. The lead screw 51 is parallel to the output shaft of the first drive motor 20, and the lead screw 51 can be fitted onto the axis of the second synchronous pulley 42. Thus, when the lead screw 51 rotates forward and backward with the second synchronous pulley 42, the nut 52 fitted onto it can reciprocate up and down along the lead screw 51 under the guidance of the thread.

[0036] In this embodiment, both the first drive motor 20 and the second drive motor 30 can be stepper motors. The controller 11 can be integrated on the PCB board 10 to connect to an internal or external power supply to implement the motor control functions described in the embodiments of this application. Typically, the controller 11 can be an integrated circuit including a microcontroller (MCU). As is well known to those skilled in the art, the microcontroller 11 may include a central processing unit (CPU), a read-only memory (ROM), a random access memory (RAM), a timing module, an analog-to-digital converter (A / D converter), and several input / output ports. Of course, the control device can also use other types of integrated circuits, such as application-specific integrated circuits (ASICs) or field-programmable gate arrays (FPGAs).

[0037] Nut 52 is connected to push rod 61 of injector 60 via connector 54. Thus, when nut 52 reciprocates up and down along lead screw 51, it simultaneously drives push rod 61 of injector 60 to reciprocate up and down. Figure 4 As shown, when the push rod 61 of the injector 60 moves upward, the fluid is discharged from the injector 60; conversely, when the push rod 61 of the injector 60 moves downward, the fluid is drawn into the injector 60 from the outside.

[0038] In terms of the specific installation structure, the injection pump also includes a frame 101. The lower end of the lead screw 51 can be fixed to the frame 101 through a bearing sleeve, and the upper end of the lead screw is sleeved in a sleeve bearing. A wave spring (not shown) is axially fitted to the sleeve bearing. With this arrangement, the wave spring can axially tension the sleeve bearing, ensuring that the sleeve bearing will not move up and down during the use of the injection pump.

[0039] Continue to cooperate with the participants Figure 4 In this embodiment, the injection pump 100 further includes a guide shaft 53 parallel to the lead screw 51, and a connector 54 is slidably fitted onto the guide shaft 53. The guide shaft 53, together with the lead screw 51, precisely guides the movement direction of the nut 52, ensuring smoother control of the injector 60 push rod 61. Specifically, the injector 60 push rod 61 is arranged parallel to and spaced apart from the lead screw 51. The connector 54 includes a horizontal connecting arm 541 located between the injector 60 push rod 61 and the lead screw 51. The horizontal connecting arm 541 has a first position at the bottom and a second position at the top. When the horizontal connecting arm 541 is in the first position, the injector 60 push rod 61 is in the maximum extension state; and when the horizontal connecting arm 541 is in the second position, the injector 60 push rod 61 is in the maximum advance state.

[0040] Coordination Figure 6 In this embodiment, the diameter R1 of the first synchronous pulley 41 is smaller than the diameter R2 of the second synchronous pulley 42. That is, by using the directly driven "small pulley" as the driving pulley and the transmission-connected "large pulley" as the driven pulley, a low-speed torque-increasing function is achieved, making the kinetic energy transmission more stable and reliable, thereby realizing precise control of the fluid flow rate sucked in or discharged by the injection pump 100. Specifically, in some embodiments, the ratio of the diameter R1 of the first synchronous pulley 41 to the diameter R2 of the second synchronous pulley 42 can be between 1:1.5 and 1:2.5, especially, the ratio of the diameter R1 of the first synchronous pulley 41 to the diameter R2 of the second synchronous pulley 42 is 1:2.1.

[0041] For example, when the diameter of the first synchronous pulley 41 is 20mm, the diameter of the second synchronous pulley 42 can be selected as 30mm, 35mm, 42mm, 50mm, etc. The specific diameter selection can also consider the compactness of the injection pump 100's structural arrangement. For example, since the second synchronous pulley 42 is located below the nut 52 sleeved on the lead screw 51, the diameter of the second synchronous pulley 42 should not be larger than the corresponding specification of the nut 52. This application does not impose any restrictions in this regard.

[0042] The first synchronous pulley 41 and the second synchronous pulley 42 can be connected by a suitable transmission method. For example, the first synchronous pulley 41 and the second synchronous pulley 42 can be provided with interlocking teeth. Alternatively, in this embodiment, the rotary transmission assembly 40 includes a transmission belt 43 that is fitted onto the first synchronous pulley 41 and the second synchronous pulley 42. The first synchronous pulley 41 and the transmission belt 43, as well as the second synchronous pulley 42 and the transmission belt, are connected by interlocking positioning protrusions and positioning grooves. The transmission method using the transmission belt 43 can ensure better noise reduction, and the transmission connection method using positioning protrusions and positioning grooves can further improve the precision of the transmission system.

[0043] For example, both the first synchronous pulley 41 and the second synchronous pulley 42 can be herringbone gears (corresponding to positioning protrusions 411 and 421 respectively), and the transmission belt 43 is provided with positioning grooves (not shown) that correspond to the herringbone pattern. This type of transmission belt 43 can also effectively prevent the transmission belt 43 from shifting, and improve the stability of the operation of the injection pump 100 system.

[0044] To further improve the precision of the syringe pump 100, in one embodiment, the syringe pump 100 may further include a first encoder 22 for monitoring the rotation angle of the first drive motor 20, and a controller 11 for comparing the rotation pulses controlling the rotation of the first drive motor 20 with the feedback pulses of the first encoder 22 to perform rotation pulse compensation on the first drive motor 20. Similarly, the syringe pump 100 may further include a second encoder 31 for monitoring the rotation angle of the second drive motor 30, and a controller 11 for comparing the rotation pulses controlling the rotation of the second drive motor 30 with the feedback pulses of the second encoder 31 to perform rotation pulse compensation on the second drive motor 30.

[0045] In one embodiment, the syringe pump 100 can also be used in conjunction with an external weighing module (not shown, such as a precision balance). This weighing module is used to detect the mass of the injection fluid from the injector 60, and then determine the precision and / or accuracy of the syringe pump 100 based on the mass of the injection fluid. For example, the weighing module can collect a certain amount of data on the injection fluid from the injector 60, and compare and analyze this data with the injection fluid volume corresponding to the command from the controller 11, thereby determining the precision and accuracy of the syringe pump 100.

[0046] In one embodiment, the injection pump 100 further includes a proximity sensor 21 mounted on the first drive motor 20. The proximity sensor 21 is used to detect the position of the nut 52 to determine the zero point position of the injector 60. The type of proximity sensor 21 can be selected according to the actual application scenario, such as inductive proximity sensor, capacitive proximity sensor, ultrasonic proximity sensor, infrared proximity sensor, photoelectric proximity sensor, magnetic proximity sensor, and LiDAR proximity sensor, etc., and this application does not limit it in this regard.

[0047] In one embodiment, the infusion pump 100 further includes a communication module for communicating with external devices, the communication module being RS485 and / or CANopen. The communication module can similarly be integrated with the controller 11 onto the PCB board 10, thereby allowing the PCB board 10 to be connected to external devices such as a computer, enabling updates to the control program of the infusion pump 100 and achieving firmware upgrades.

[0048] In the use of the syringe pump provided in the above embodiment, the PCB board 10 (controller 11) drives the push rod 61 of the injector 60 through the first drive motor 20, the rotary transmission assembly 40, and the linear transmission assembly 50. Simultaneously, the PCB board 10 (controller 11) also drives the rotary valve 70 to rotate through the second drive motor 30 and the coupling 71. During this process, as the rotary valve 70 rotates, the injector 60 switches between different inlet or outlet ports. Combined with the reciprocating motion of the push rod 61, fluid can be drawn from a designated inlet port or discharged from a designated outlet port. In the overall transmission structure, the rotary transmission assembly, in addition to using a synchronous pulley with better noise reduction, also adopts a rotary transmission mode where a smaller pulley actively drives a larger pulley. This achieves low-speed torque increase while making kinetic energy transmission more stable and reliable, thereby realizing precise control of the fluid flow rate drawn in or discharged by the syringe pump.

[0049] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0050] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. An injection pump, characterized in that, The injection pump includes a controller, a first drive motor, a second drive motor, a rotary transmission assembly, a linear transmission assembly, an injector, and a rotary valve; The first drive motor can be controlled by a controller to drive the push rod of the injector to reciprocate through a rotary transmission assembly and a linear transmission assembly, thereby drawing fluid into the injector or expelling fluid from the injector. The second drive motor can be controlled by the controller to switch the fluid inlet and / or fluid outlet of the injector via a rotary valve; The rotary transmission assembly includes a first synchronous pulley connected to the output end of the first drive motor and a second synchronous pulley that is drively connected to the first synchronous pulley. The second synchronous pulley is connected to a linear transmission assembly to convert the rotary driving force of the first drive motor into a linear driving force. The diameter of the first synchronous pulley is smaller than the diameter of the second synchronous pulley.

2. The syringe pump according to claim 1, characterized in that, The ratio of the diameter of the first synchronous pulley to the diameter of the second synchronous pulley is between 1:1.5 and 1:2.

5.

3. The syringe pump according to claim 1, characterized in that, The diameter ratio of the first synchronous pulley to the diameter of the second synchronous pulley is 1:2.

1.

4. The syringe pump according to any one of claims 1 to 3, characterized in that, The rotary transmission assembly also includes a transmission belt fitted onto the first synchronous pulley and the second synchronous pulley. The first synchronous pulley and the transmission belt, as well as the second synchronous pulley and the transmission belt, are connected by a positioning protrusion and a positioning groove that can mesh with each other.

5. The syringe pump according to claim 1, characterized in that, The linear transmission assembly includes a lead screw and a nut fitted on the lead screw. The lead screw is parallel to the output shaft of the first drive motor, and the nut is connected to the push rod of the sampler via a connecting piece. The injection pump also includes a guide shaft parallel to the lead screw, and the connector is slidably fitted onto the guide shaft.

6. The syringe pump according to claim 5, characterized in that, The push rod and lead screw of the injector are arranged parallel to each other at intervals. The connector includes a horizontal connecting arm located between the push rod and the lead screw of the injector. The horizontal connecting arm has a first position at the bottom end and a second position at the top end. When the horizontal connecting arm is in the first position, the push rod of the injector is in the maximum tension state; When the horizontal connecting arm is in the second position, the push rod of the injector is in the maximum advance state.

7. The syringe pump according to claim 5, characterized in that, The injection pump also includes a proximity sensor mounted on the first drive motor, which is used to detect the position of the nut to determine the zero point position of the injector.

8. The syringe pump according to claim 1, characterized in that, The injection pump includes a first encoder for monitoring the rotation angle of a first drive motor, and the controller is used to compare the rotation pulses controlling the rotation of the first drive motor with the feedback pulses of the first encoder to perform rotation pulse compensation on the first drive motor. And / or, the injection pump includes a second encoder for monitoring the rotation angle of the second drive motor, and the controller is used to compare the rotation pulses controlling the rotation of the second drive motor and the feedback pulses of the second encoder to perform rotation pulse compensation on the second drive motor.

9. The syringe pump according to claim 1, characterized in that, The injection pump also includes a coupling connecting the output shaft of the second drive motor and the rotary valve.

10. The syringe pump according to claim 1, characterized in that, The injection pump also includes a communication module for communicating with external devices, wherein the communication module is RS485 and / or CANopen.

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