CN118576819A - A multi-stage lifting structure and an infusion device including the multi-stage lifting structure - Google Patents

Abstract

The invention discloses a multi-stage lifting structure and an infusion set including the multi-stage lifting structure. The beneficial effects are as follows: 1. The motor rotational motion is transmitted to the long gear through the gear transmission device, and the third gear ensures that the long gear is evenly stressed, ensures the concentricity of the transmission mechanism and the pen core, avoids the subsequent possible thrust instability, high noise and other problems, and improves the stability of the infusion accuracy; 2. The rotation of the long gear is converted into up and down (lifting) linear motion through the inner thread of the driving frame and the inner thread of the long tooth, combined with the restriction of the anti-rotation rod of the guide shaft, so as to realize the infusion and reset functions, and the inner thread of the driving frame and the inner thread of the long tooth have opposite rotation directions and the same pitch, so the threads at both ends advance and retreat at the same time and at equal distances, and the multi-stage lifting structure always pushes the pen core piston at a constant speed to ensure the infusion volume and accuracy, which can ensure that the amount of insulin entering the patient's subcutaneous tissue is evenly ingested, and avoids the possibility of impact or even jamming during the first and second stage transmission conversion process.

Description

A multi-stage lifting structure and an infusion device including the multi-stage lifting structure

Technical Field

The present invention relates to the field of medical devices, and in particular to a multi-stage lifting structure and an infusion set comprising the multi-stage lifting structure.

Background Art

Diabetes is a chronic disease that endangers the health of society and human beings. Its degree of harm is currently ranked third among all diseases and continues to increase. Controlling the fluctuation range of blood sugar can prevent the occurrence of various serious complications. It is now recognized that insulin injection is the most effective way to control blood sugar. The traditional injection method is manual injection. At present, it is a common expectation of doctors and patients to develop a portable medical device to replace the secretion of insulin in the human pancreas, so that blood sugar can reach an ideal regulation level similar to that in physiological conditions. However, the amount of insulin injected each time is very small. How to control the injection amount of insulin with high precision and at the same time require the injection pump to be small in size is a difficult problem that needs to be solved urgently. After inquiry, the relevant patent documents in the existing patent documents, such as CN202010948555.4 A two-stage drive injection device for an insulin pump, the objective shortcomings of the prior art (one or more shortcomings that can be solved or improved by this patent):

1. The transmission mechanism is positioned by the upper and lower positioning rings located on the upper shell and bottom shell respectively. It is difficult to ensure the concentricity of the transmission mechanism and the pen core, resulting in subsequent problems such as unstable thrust and loud noise, which ultimately affects the stability of infusion accuracy. These are one of the important reasons for the "less injection" and "more injection" phenomena.

2. The structure is complex. If it is to meet the current requirements for portable insulin pumps to be increasingly "light and thin", while taking into account the strength and wear resistance requirements of the transmission mechanism and the market demand for an 8-year service life of the insulin pump, it is too difficult to achieve in actual applications due to the limited product volume requirements, or it is not safe and effective enough.

3. For the two-stage drive mode of the patent, there may be uncertainty in the first and second stage transmission actions and the possibility of impact or even jamming during the conversion process of the first and second stage transmission during actual use. The patent mentions the use of relevant sensors and control methods, among which the measures of reducing the speed and torque to solve this problem will inevitably affect the final infusion accuracy. Imagine that if a patient needs to inject a large dose before a meal, the motion mechanism always pushes the pen core piston at a constant speed to ensure the infusion volume and accuracy. Once the speed and torque are reduced, it will definitely affect the amount of insulin that finally enters the patient's subcutaneous tissue, and the blood sugar level after the meal will definitely not drop.

4. According to the "micro" requirement of insulin pump for infusion, it is difficult to achieve the required infusion accuracy using trapezoidal thread transmission. The pitch of trapezoidal thread is several times that of triangular thread and the transmission efficiency is also low. If compared with triangular thread transmission under the same output stroke and time condition, its accuracy may differ by more than three times.

Summary of the invention

The purpose of the present invention is to provide a multi-stage lifting structure and an infusion set including the multi-stage lifting structure in order to solve the above-mentioned problems, as described in detail below.

To achieve the above object, the present invention provides the following technical solutions:

The present invention provides an infusion device, comprising a multi-stage lifting structure, wherein the multi-stage lifting structure comprises a power source, a driving housing, a transmission device and a multi-stage lifting assembly;

The driving housing is provided with a driving fixed cover and a driving fixed frame, the driving fixed cover is covered on the driving fixed frame to form a containing chamber, the containing chamber includes a transmission chamber and a lifting chamber, the transmission device is installed in the transmission chamber, and the multi-stage lifting assembly is installed in the lifting chamber;

The power source can enable the multi-stage lifting assembly to be lifted and lowered through a transmission device.

Preferably, the transmission device is a gear transmission structure; the multi-stage lifting assembly includes a long gear, a push rod and a guide shaft; the long gear is provided with external teeth, long tooth external threads and long tooth internal threads; the drive fixing frame is provided with a drive frame internal thread; the long tooth external thread is provided at the bottom of the long gear; the long tooth external thread cooperates with the drive frame internal thread; the push rod is provided with a push rod external thread, a push rod anti-rotation groove and a limit boss; the long tooth internal thread cooperates with the push rod external thread; the guide shaft is provided with a guide anti-rotation rod, an anti-rotation limit one and an anti-rotation limit two; the guide anti-rotation rod passes through the push rod anti-rotation groove; the guide anti-rotation rod cooperates with the push rod anti-rotation groove; the drive fixing frame is provided with a drive frame anti-rotation groove, and the drive frame anti-rotation groove cooperates with the anti-rotation limit one and the anti-rotation limit two.

Preferably, the thread directions of the drive frame internal thread and the long-tooth internal thread are opposite, and the pitches of the drive frame internal thread and the long-tooth internal thread are the same.

Preferably, the gear transmission device includes a first gear and a second gear; the power source is a motor, the output end of the motor is connected to the second gear, and the second gear transmits kinetic energy to the long tooth via the first gear.

Preferably, the transmission device further comprises a third gear, wherein the third gear is arranged on one side of the long gear, and the third gear cooperates with the first gear to transmit and support the long gear.

Preferably, it also includes a shell, an injection structure, a control unit and a switch sensing component; the injection structure, the control unit and the switch sensing component are all installed in the shell, and the switch sensing component and the control unit are electrically connected; the injection structure includes a refill, a piston and an infusion line; the refill is vertically arranged in the upper inner part of the shell, the piston is slidably sealed on the inner wall of the refill, the infusion line is arranged at the upper end of the refill and extends out of the shell, and the upper end of the push rod is in contact with the bottom surface of the piston.

Preferably, the switch sensing assembly includes an identification switch, an in-place switch and a film pressure sensor; the shell includes an injection core compartment, a battery compartment and a back cover; the pen core is installed in the injection core compartment; the battery is installed in the battery compartment; the back cover is arranged at the bottom of the shell; the in-place switch is arranged at the in-place switch mounting part at the bottom of the drive fixed frame; the in-place switch mounting part is provided with a groove, and the in-place switch is installed in the groove; the identification switch is located above the drive fixed frame and on one side of the injection structure, and is used to detect the model of the injection structure; the film pressure sensor is located between the push rod and the piston, and is used to sense the pressure of the push rod and the piston.

Preferably, a first 3D circuit is arranged on the push rod; a first conductive silicone is arranged at the connection between the push rod and the guide shaft; a second conductive silicone is arranged on both sides of the tail end of the guide shaft and the connection with the drive fixed frame; a third 3D circuit is arranged on the drive fixed frame; the first 3D circuit on the push rod connects the first conductive silicone and the thin film pressure sensor, and during the movement of the push rod, the first conductive silicone contacts the second 3D circuit on the guide shaft by relying on its own elasticity; the second conductive silicone contacts the third 3D circuit, and the thin film pressure sensor signal is transmitted to the control unit through the flexible FPC located at the bottom of the driver fixed frame through the connector.

Preferably, a return spring is further included, and the return spring is arranged at the bottom of the guide shaft.

Preferably, it further includes positioning pins, and there are multiple positioning pins, and the multiple positioning pins fix the first gear and the third gear on the driving fixed frame.

Preferably, the power source is a motor.

The beneficial effects are: 1. The motor rotation motion is transmitted to the long gear through the gear transmission device, and the third gear ensures that the long gear is evenly stressed, ensures the concentricity of the transmission mechanism and the pen core, avoids possible subsequent thrust instability, high noise and other problems, improves the stability of infusion accuracy, and greatly reduces or eliminates the "less injection" and "more injection" phenomena; 2. The rotation of the long gear is converted into up and down (lifting) linear motion through the internal thread of the driving frame and the long tooth internal thread, combined with the limitation of the guide shaft anti-rotation rod, thereby realizing the infusion and reset functions, and the internal thread of the driving frame and the long tooth internal thread have opposite rotation directions and the same pitch, so the threads at both ends advance and retreat simultaneously and equidistantly, and the multi-stage lifting structure always pushes the pen core piston at a constant speed to ensure the infusion volume and accuracy, which can ensure that the amount of insulin entering the patient's subcutaneous tissue is evenly ingested, avoids the possibility of impact or even jamming during the first and second stage transmission conversion processes, and increases the service life and accuracy of the equipment. The two sections of the thread move to a certain height, driving the guide shaft to move up and down along the anti-rotation groove of the drive frame, continuously limiting the push rod to only move up and down (lifting and lowering) until the refill piston is pushed to the top or the push rod is reset to the origin; 3. By setting, resetting and controlling the maximum stroke, process control and infusion accuracy at the starting origin, it is achieved by hardware such as a thin film pressure sensor, a stroke switch, and an identification switch through various software algorithms. The action is continuous without considering the sequence, which increases the stability of the equipment and ensures the safety of injection; 4. Each sensing element conducts electricity through a 3D circuit and conductive silicone, which can increase the stability of the equipment's electronic control, and the structure is simple and reasonable, reducing the trouble of wiring; 5. The refill manufacturer or size can be identified through the identification switch, and the identification result can be displayed for easy operation by the operator.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

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

Fig. 2 is an exploded view of the present invention;

FIG3 is a schematic diagram of the structure of a multi-stage lifting device with a pen core according to the present invention;

FIG4 is an exploded view of the multi-stage lifting device of the present invention with a pen core:

FIG5 is a schematic diagram of the structure of the gear transmission of the present invention:

FIG6 is a schematic diagram of the analysis of the diaphragm pressure sensor for the push rod movement thread transmission of the present invention;

FIG7 is a schematic structural diagram of a multi-stage lifting device of the present invention;

FIG8 is a schematic diagram of the structure of a drive fixing frame of the present invention;

FIG9 is a schematic diagram of the structure of a long gear of the present invention:

FIG10 is a cross-sectional view of a long gear of the present invention;

FIG. 11 is a schematic diagram of the structure of the mandrel of the present invention.

FIG12 is a cross-sectional view of the mandrel of the present invention:

FIG. 13 is a schematic structural diagram of the guide shaft of the present invention.

The following are the descriptions of the reference numerals:

1. Pen core; 2. Injection core chamber; 3. Piston; 4. Driving device; 5. Driving housing; 501. Driving fixed cover; 502. Driving fixed frame; 5021. Transmission chamber; 5022. Driving frame internal thread; 5023. Driving frame anti-rotation groove; 5024. Lifting chamber; 5025. In-position switch installation part; 6. Transmission device; 601. First gear; 602. Second gear; 603. Third gear; 7. Multi-stage lifting assembly; 701. Long gear; 7011. External teeth; 7012. Long tooth external thread; 7013. Long tooth internal thread; 702. Push rod; 7021, push rod external thread; 7022, push rod anti-rotation groove; 703, guide shaft; 7031, guide anti-rotation rod; 7032, anti-rotation limit 1; 7033, anti-rotation limit 2; 8, in-position switch; 9, reset spring; 10, back cover; 11, identification switch; 12, control unit; 13, housing; 14, battery compartment; 15, fixing part; 16, film pressure sensor; 17, first 3D circuit; 18, second 3D circuit; 19, third 3D circuit; 20, first conductive silicone; 21, second conductive silicone; 22, positioning flange.

DETAILED DESCRIPTION

To make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described in detail below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other implementation methods obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

1 to 6 , an infusion set provided by the present invention includes a multi-stage lifting structure, wherein the multi-stage lifting structure includes a power source, a driving housing 5 , a transmission device 6 and a multi-stage lifting assembly 7 ;

Referring to FIG. 8 , the driving housing 5 is provided with a driving fixed cover 501 and a driving fixed frame 502. The driving fixed cover 501 covers the driving fixed frame 502 to form a receiving chamber. The receiving chamber includes a transmission chamber 5021 and a lifting chamber 5024. The transmission device 6 is installed in the transmission chamber 5021, and the multi-stage lifting assembly 7 is installed in the lifting chamber 5024.

The power source can enable the multi-stage lifting assembly 7 to be lifted and lowered through the transmission device 6 .

In this embodiment, the transmission device 6 is a gear transmission structure; the multi-stage lifting assembly 7 includes a long gear 701, a push rod 702 and a guide shaft 703; referring to Figures 9 and 10, the long gear 701 is provided with an external tooth 7011, a long tooth external thread 7012 and a long tooth internal thread 7013; referring to Figure 8, the driving fixed frame 502 is provided with a driving frame internal thread 5022; the long tooth external thread 7012 is provided at the bottom of the long gear 701; the long tooth external thread 7012 and the driving frame internal thread 5022 cooperate; referring to Figures 11 and 12, the push rod 702 is provided with a push rod 702 external thread, a push rod 702 anti-rotation groove and a limiting boss; the long tooth internal thread 7013 And cooperate with the external thread of the push rod 702; the guide shaft 703 is provided with a guide anti-rotation rod 7031, an anti-rotation limit 1 7032 and an anti-rotation limit 2 7033; the guide anti-rotation rod 7031 passes through the anti-rotation groove of the push rod 702; referring to Figure 13, the guide anti-rotation rod 7031 cooperates with the anti-rotation groove of the push rod 702; the driving fixed frame 502 is provided with a driving frame anti-rotation groove 5023, and the driving frame anti-rotation groove 5023 cooperates with the anti-rotation limit 1 7032 and the anti-rotation limit 2 7033; there are two driving frame anti-rotation grooves 5023, and the two driving frame anti-rotation grooves 5023 cooperate with the anti-rotation limit 1 7032 and the anti-rotation limit 2 7033 respectively. The drive frame anti-rotation groove 5023 on the driver fixing frame cooperates with the anti-rotation limiter 1 7032 and the anti-rotation limiter 2 7033. Because the driver fixing frame is fixed, the guide shaft 703 can only slide up and down along the anti-rotation groove. In this embodiment, the thread directions of the drive frame internal thread 5022 and the long tooth internal thread 7013 are opposite, and the pitch of the drive frame internal thread 5022 and the long tooth internal thread 7013 is the same. The internal thread of the driver fixing frame and the internal thread of the long tooth have the same pitch and continuous tooth shape, wherein the pitch and thread are the same and the rotation direction is opposite. And the driver fixing frame anti-rotation groove. The internal thread of the driver fixing frame is connected with the external thread of the long gear 701, and the gear transmission system rotates and transmits to the long gear 701. Because the driver fixing frame is fixed, the movement state of the long gear 701 under the drive of the internal thread of the driver fixing frame is rotation + linear motion up and down; the internal thread of the long gear 701; the long gear 701 rotates under the rotation drive of the internal thread of the driver fixing frame and slides linearly up and down along the tooth shape. At the same time, the long tooth internal thread 7013 is connected to the external thread of the push rod 702, and because of the limitation of the guide shaft 703, the push rod 702 and the long gear 701 rise or fall at the same time and at the same distance; the external thread of the push rod 702 cooperates with the long tooth internal thread 7013 on the long gear 701; the square groove cooperates with the square rod position on the guide shaft 703, and the push rod 702 can only move linearly up and down under the drive of the long tooth internal thread 7013 but cannot rotate, and the push rod 702 has completed the up and down movement of the long tooth internal thread 7013.

In this embodiment, the gear transmission device 6 includes a first gear 601 and a second gear 602; the power source is a motor, the output end of the motor is connected to the second gear 602, and the second gear 602 transmits kinetic energy to the long teeth through the first gear 601. The first gear 601 is fixed in the transmission cavity 5021 in the driving fixed frame 502 by a positioning pin;

In this embodiment, the transmission device 6 further includes a third gear 603, which is disposed on one side of the long gear 701. The third gear 603 cooperates with the first gear 601 to transmit and support the long gear 701. The second gear 602 is fixed in the transmission cavity 5021 in the drive fixing frame 502 by means of a positioning pin; the long gear 701 can be fixed by the cooperation of the first gear 601 and the third gear 603, so as to ensure that the position of the long gear 701 is kept stable, the force is evenly applied, and the noise can be reduced.

In this embodiment, it also includes a housing 13, an injection structure, a control unit 12 and a switch sensing component; the injection structure, the control unit 12 and the switch sensing component are all installed in the housing 13, and the switch sensing component is electrically connected to the control unit 12; the injection structure includes a refill 1, a piston 3 and an infusion line; the refill 1 is vertically arranged in the upper part of the housing 13, the piston 3 is slidably sealed on the inner wall of the refill 1, the infusion line is arranged at the upper end of the refill 1 and extends out of the housing 13, and the upper end of the ejector 702 is in contact with the bottom surface of the piston 3. The control unit 12 can output corresponding control components according to the input signal.

In this embodiment, the switch sensing assembly includes an identification switch 11, an in-position switch 8 and a film pressure sensor 16; the housing 13 includes an injection core compartment 2, a battery compartment 14 and a back cover 10; the refill 1 is installed in the injection core compartment 2; the battery is installed in the battery compartment 14; the back cover 10 is arranged at the bottom of the housing 13; the in-position switch 8 is arranged at the in-position switch mounting portion 5025 at the bottom of the drive fixing frame 502; the in-position switch mounting portion 5025 is provided with a groove, and the in-position switch 8 is installed in the groove; the identification switch 11 is located above the drive fixing frame 502 and on one side of the injection structure, and is used to detect the model of the injection structure; the film pressure sensor 16 is located between the push rod 702 and the piston 3, and is used to sense the pressure of the push rod 702 and the piston 3. The drive fixing cover 501 and the drive fixing frame 502 are connected by equal height screws, and the thickness position of the film pressure sensor 16 is adjusted by the equal height screws to apply pre-pressure; the transmission device 6 is fixed in the accommodating cavity. The identification switch 11 automatically identifies refills 1 of different specifications. The in-position switch 8 detects whether the guide shaft 703 returns to its original position or not. The change in thrust during the screw pushing of the film pressure sensor 16 causes the strain gauge inside the film pressure sensor 16 to deform slightly, thereby generating an electrical signal to judge various states such as blockage, leakage, and normal infusion according to various situations.

In this embodiment, see Figure 6: a first 3D circuit 17 is arranged on the push rod 702; a first conductive silicone 20 is arranged at the connection between the push rod 702 and the guide shaft 703; a second conductive silicone 21 is arranged on both sides of the tail end of the guide shaft 703 and the connection with the drive fixed frame 502; a third 3D circuit 19 is arranged on the drive fixed frame 502; the first 3D circuit 17 on the push rod 702 connects the first conductive silicone 20 and the thin film pressure sensor 16, and during the movement of the push rod 702, the first conductive silicone 20 relies on its own elasticity to contact the second 3D circuit 18 located on the guide shaft 703; the second conductive silicone 21 contacts the third 3D circuit 19, and the signal of the thin film pressure sensor 16 is transmitted to the control unit 12 through the flexible FPC located at the bottom of the driver fixed frame through the connector. The force analysis of the thin film pressure sensor 16 of the threaded transmission is schematically explained: when the push rod 702 pushes the piston 3 of the pen core 1 upward for infusion, the resistance F acts directly on the thin film pressure sensor 16. When F causes the strain gauge of the thin film pressure sensor 16 to deform, an electrical signal is generated, and various states such as blockage, leakage, and normal infusion are judged according to various situations. The first 3d circuit 17 located on the push rod 702 connects the first conductive silicone 20 and the thin film pressure sensor 16, and during the movement of the push rod 702, the first conductive silicone 20 relies on its own elasticity to make good contact with the second 3d circuit 18 located on the guide shaft 703. There are second conductive silicone 21 on both sides of the tail end of the guide shaft 703, which rely on its own elasticity to make good contact with the third 3d circuit 19 located on the driver fixing frame. The signal of the thin film pressure sensor 16 is transmitted to the control unit 12 through the flexible FPC located at the bottom of the driver fixing frame through the connector, wherein the first 3D circuit 17, the second 3D circuit 18, and the third 3D circuit 19 are all three-dimensional conformal circuits 3D (3D-M ID) or other replaceable 3D circuits 3D, and the first conductive silicone rubber 20 and the second conductive silicone rubber 21 are existing conductive silicone rubber or replaceable similar products.

In this embodiment, a return spring 9 is also included. The return spring 9 is arranged at the bottom of the guide shaft 703 to play an auxiliary buffering role.

In this embodiment, positioning pins are also included. There are multiple positioning pins, and the multiple positioning pins fix the first gear 601 and the third gear 603 on the driving fixed frame 502.

In this embodiment, the power source is a motor.

The installation method of the transmission device 6 is as follows:

As shown in Figures 4 and 7, step 1: use the long tooth internal thread 7013 and the external thread of the push rod 702 to match; screw the push rod 702 into the threaded hole of the long gear 701 in a counterclockwise direction, and stop when the limiting boss of the push rod 702 contacts the end face of the long gear 701.

Step 2: Screw the mating parts in step 1 into the inner thread 5022 of the drive frame clockwise from the gear cavity of the driver fixing frame until the end of the long gear 701 is flush with the end of the inner thread 5022 of the drive frame.

Step 3: Install the guide shaft 703 with the return spring 9 bonded thereto into the square groove of the top rod 702 and tighten it with screws at the flange end of the top rod 702.

Step 4: Install the second gear 602 into the motor output shaft, and then install the motor into the motor positioning cavity on the driver fixing cover according to the direction shown in the figure.

Step 5: Install the positioning pin into the gear cavity of the driver fixing frame and install the first gear 601 and the second gear 602 into the corresponding positions respectively.

Step 6: Assemble the drive fixing cover and the drive fixing frame until they snap into place.

Step 7: Position and fix the above device in the housing 13 and tighten it with fixing screws.

Note: Connect the transmission device 6 and the housing 13 through the positioning flange 22 to ensure the concentricity of the refill 1 and the transmission device 6:

Use this example as follows:

The beneficial effects are as follows: 1. The motor rotational motion is transmitted to the long gear 701 through the gear transmission device 6, and the third gear 603 ensures that the long gear 701 is evenly stressed, ensures the concentricity of the transmission mechanism and the pen core 1, avoids the subsequent possible thrust instability, high noise and other problems, improves the stability of the infusion accuracy, and greatly reduces or eliminates the "less injection" and "more injection" phenomena; 2. The rotation of the long gear 701 is converted into up and down (lifting) linear motion through the driving frame inner thread 5022, the long tooth inner thread 7013, and combined with the restriction of the anti-rotation rod of the guide shaft 703, so as to realize the infusion and reset functions, and the driving frame inner thread 5022 and the long tooth inner thread 7013 have opposite rotation directions and the same pitch, so the threads at both ends advance and retreat at the same time and at equal distances, and the multi-stage lifting structure always pushes the pen core 1 piston 3 at a constant speed to ensure the infusion volume and accuracy, which can ensure that the amount of insulin entering the patient's subcutaneous tissue is evenly ingested, avoids the possibility of impact or even jamming during the first and second stage transmission conversion processes, and increases the service life and accuracy of the device. The two sections of the thread move to a certain height, driving the guide shaft 703 to move up and down along the anti-rotation groove 5023 of the driving frame, continuously limiting the push rod 702 to only up and down (lifting) movement, until the piston 3 of the pen core 1 is pushed to the top or the push rod 702 is reset to the origin; 3. By setting, resetting and controlling the maximum stroke, process control and infusion accuracy at the starting origin and through various software algorithms, the thin film pressure sensor 16, stroke switch, identification switch 11 and other hardware are used to achieve continuous action without considering the sequence, thereby increasing the stability of the equipment and ensuring the safety of injection; 4. Each sensing element conducts electricity through the 3d circuit 3d3d3d and conductive silicone, which can increase the stability of the electronic control of the equipment, and the structure is simple and reasonable, reducing the trouble of wiring; 5. The manufacturer or size of the pen core 1 can be identified through the identification switch 11, and the identification result can be displayed, which is convenient for the operator to operate.

The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art who is familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (10)

1. A multistage elevation structure, its characterized in that: comprises a power source, a driving shell, a transmission device and a multi-stage lifting assembly;

The driving shell is provided with a driving fixed cover and a driving fixed frame, the driving fixed cover covers the driving fixed frame and forms a containing cavity, the containing cavity comprises a transmission cavity and a lifting cavity, the transmission device is arranged in the transmission cavity, and the multistage lifting assembly is arranged in the lifting cavity;

the power source can enable the multistage lifting assembly to lift through the transmission device.

2. The multi-stage lifting structure of claim 1, wherein: the transmission device is of a gear transmission structure; the multistage lifting assembly comprises a long gear, a push rod and a guide shaft; the long gear is provided with external teeth, long tooth external threads and long tooth internal threads; the driving fixing frame is provided with driving frame internal threads; the long tooth external thread is arranged at the bottom of the long gear; the long tooth external thread is matched with the driving frame internal thread; the ejector rod is provided with an ejector rod external thread, an ejector rod anti-rotation groove and a limiting boss; the long tooth internal thread is matched with the ejector rod external thread; the guide shaft is provided with a guide anti-rotation rod, an anti-rotation limit I and an anti-rotation limit II; the guide anti-rotation rod passes through the ejector rod anti-rotation groove; the guide anti-rotation rod is matched with the ejector rod anti-rotation groove; the driving fixing frame is provided with a driving frame rotation preventing groove, and the driving frame rotation preventing groove is matched with the first rotation preventing limit and the second rotation preventing limit.

3. The multi-stage lifting structure of claim 2, wherein: the thread directions of the driving frame internal thread and the long tooth internal thread are opposite, and the thread pitches of the driving frame internal thread and the long tooth internal thread are the same.

4. A multi-stage lifting structure as claimed in claim 3 wherein: the gear transmission device comprises a first gear and a second gear; the power source is a motor, the output end of the motor is connected with a second gear, and the second gear transmits kinetic energy to the long teeth through the first gear.

5. The multi-stage lift structure of claim 4 wherein: the transmission device further comprises a third gear, the third gear is arranged on one side of the long gear, and the third gear is matched with the first gear and used for transmitting and supporting the long gear.

6. An infusion set comprising the multi-stage lifting structure of claim 5; the method is characterized in that: the injection device also comprises a shell, an injection structure, a control unit and a switch induction assembly; the injection structure, the control unit and the switch induction component are all arranged in the shell, and the switch induction component is electrically connected with the control unit; the injection structure comprises a pen core, a piston and an infusion pipeline; the pen core is vertically arranged at the upper part in the shell, the piston is sealed on the inner wall of the pen core in a sliding manner, the infusion pipeline is arranged at the upper end of the pen core and stretches out of the shell, and the upper end of the ejector rod is contacted with the bottom surface of the piston.

7. The multi-stage lift structure of claim 6 wherein: the switch induction component comprises an identification switch, an in-place switch and a film pressure sensor; the shell comprises an injection core bin, a battery bin and a rear cover; the pen refill is arranged in the injection core bin; the battery is arranged in the battery compartment; the rear cover is arranged at the bottom of the shell; the in-place switch is arranged at the in-place switch mounting part at the bottom of the driving fixed frame; the in-place switch installation part is provided with a groove, and the in-place switch is installed in the groove; the identification switch is positioned above the driving fixed frame and at one side of the injection structure and is used for detecting the model of the injection structure; the film pressure sensor is positioned between the ejector rod and the piston and is used for sensing the pressure of the ejector rod and the piston.

8. The multi-stage lift structure of claim 7 wherein: the ejector rod is provided with a first 3d circuit; a first conductive silica gel is arranged at the joint of the ejector rod and the guide shaft; the two sides of the connection part of the tail end of the guide shaft and the driving fixed frame are provided with second conductive silica gel; the driving fixed frame is provided with a third 3d circuit; the first 3d circuit on the ejector rod is connected with the first conductive silica gel and the film pressure sensor, and in the moving process of the ejector rod, the first conductive silica gel contacts with the second 3d circuit on the guide shaft by virtue of self elasticity; the second conductive silica gel is in contact with the third 3d circuit, and the signals of the film pressure sensor are transmitted to the control unit through the connector by the flexible FPC at the bottom of the driver fixing frame.

9. The multi-stage lift structure of claim 6 wherein: the guide shaft is characterized by further comprising a return spring, wherein the return spring is arranged at the bottom of the guide shaft.

10. The multi-stage lift structure of claim 6 wherein: the driving device further comprises a plurality of positioning pins, and the first gear and the third gear are fixed on the driving fixing frame by the plurality of positioning pins.