Injecting device

Abstract

The present application relates to an injection device, which includes a device housing, a control circuit arranged outside the device housing, a moving component located inside the device housing for carrying an injection agent, a magnet assembly located on the moving component and moving together with the moving component, and a magnetic reed switch arranged outside the device housing and connected to the control circuit. The magnet assembly is configured such that when the moving component moves to a predetermined position, the magnetic field of the magnet assembly changes the conduction state of the magnetic reed switch.

Description

Technical Field

[0001] The present invention relates to the field of infusion devices, and in particular, to an injection device. Background Art

[0002] Injection devices are used to inject injectables such as medicines required by the human body or animals to treat diseases or improve physiological conditions, etc. With the development of society and technology, traditional purely mechanical injection devices can no longer meet the current needs. Therefore, injection devices are also developing in the directions of intelligence, multi-function, automation, etc. For example, a detection function is added to the injection device to determine whether the injectable such as medicine is loaded and ready. However, existing injection devices with detection functions have defects such as complex structures and poor reliability. Summary of the Invention

[0003] The present application provides an improved injection device to solve at least one technical problem in the prior art.

[0004] One aspect of the present application provides an injection device, which includes a device housing, a control circuit disposed outside the device housing, a moving member located inside the device housing for carrying an injectant, a magnet assembly located on the moving member and moving together with the moving member, and a reed switch disposed outside the device housing and connected to the control circuit. The magnet assembly is configured to change the conduction state of the reed switch when the moving member moves to a predetermined position.

[0005] In one embodiment, the injection device includes a circuit protection housing located outside the device housing and attached to the device housing, and a circuit board assembly carrying the control circuit located inside the circuit protection housing. The reed switch is connected to the circuit board assembly.

[0006] In one embodiment, the device housing physically isolates the circuit board assembly from the internal space of the device housing.

[0007] In one embodiment, the control circuit includes a sleep circuit, and the reed switch is connected to the sleep circuit. When the moving member moves to a predetermined position, based on the change in the conduction state of the reed switch, the sleep circuit wakes up the injection device from the sleep state.

[0008] In one embodiment, the injection device includes a magnetic induction sensor. When the moving member moves to a predetermined position, the magnet assembly provides a magnetic field to the magnetic induction sensor. The magnetic induction sensor is configured to detect the surrounding magnetic field intensity for further confirming that the magnetic field sensed by the reed switch is from the magnet assembly.

[0009] In one embodiment, the control circuit is configured to confirm that the magnetic field sensed by the reed switch is from the magnet assembly when the magnetic field intensity detected by the magnetic induction sensor is within a preset range, and the preset range is set based on the magnetic field intensity of the magnet assembly.

[0010] In one embodiment, the control circuit includes a sleep circuit and a working circuit. The reed switch is connected to the sleep circuit, and the magnetic induction sensor is connected to the working circuit. Based on the change in the conduction state of the reed switch, the sleep circuit wakes up the injection device from the sleep state and starts the working circuit.

[0011] In one embodiment, the control circuit is configured to confirm that the magnetic field sensed by the reed switch is an external magnetic field and turn off the working circuit when the magnetic field intensity detected by the magnetic induction sensor exceeds the preset range.

[0012] In one embodiment, the injection device includes a circuit protection housing located outside the device housing and attached to the device housing, and a circuit board assembly carrying the control circuit located inside the circuit protection housing. The magnetic induction sensor is disposed on the circuit board assembly.

[0013] In one embodiment, the magnetic induction sensor includes at least one of a magnetoresistive sensor and a Hall sensor.

[0014] In one embodiment, the magnet assembly includes a first magnet and a second magnet. The injection device is configured such that when the moving member moves to a predetermined position, the magnetic field of the first magnet acts on the reed switch but is isolated from the magnetic induction sensor, and the magnetic field of the second magnet acts on the magnetic induction sensor.

[0015] In one embodiment, the first magnet and the second magnet are spaced apart by a preset distance so that the magnetic field of the first magnet is isolated from the magnetic induction sensor.

[0016] In one embodiment, the injection device includes a magnetic shielding element configured to isolate the magnetic field of the first magnet from the magnetic induction sensor.

[0017] In one embodiment, the injection device is further configured such that when the moving member moves to a predetermined position, the magnetic field intensity of the second magnet detected by the magnetic induction sensor is lower than the magnetic field intensity required to change the conduction state of the reed switch.

[0018] In one embodiment, the control circuit is configured to confirm that the magnetic field sensed by the reed switch is from the magnet assembly when the magnetic field intensity detected by the magnetic induction sensor is within a preset range, and to confirm that the magnetic field sensed by the reed switch is an external magnetic field when the magnetic field intensity detected by the magnetic induction sensor is greater than the preset range. The preset range is set based on the magnetic field intensity of the second magnet.

[0019] In one embodiment, the moving member includes a plunger, and the magnet assembly is disposed on the plunger.

[0020] In one embodiment, the predetermined position is the position to be injected.

[0021] On the other hand, the present application provides an injection device, which includes a device housing, a moving member that can reciprocate in the internal space of the device housing along the length direction of the device housing during operation, a magnet assembly located on the moving member and moving together with the moving member, a control circuit, and a reed switch connected to the control circuit. The control circuit and the reed switch are blocked and not electrically connected to the internal space of the device housing. The magnet assembly is configured such that when the moving member moves to a predetermined position, the magnetic field of the magnet assembly changes the conduction state of the reed switch.

[0022] On yet another aspect, the present application provides an injection device, which includes a device housing, a moving member that can reciprocate in the internal space of the device housing along the length direction of the device housing during operation, a magnet assembly located on the moving member and moving together with the moving member, a control circuit, and a reed switch connected to the control circuit. The control circuit and the reed switch are blocked and not electrically connected to the internal space of the device housing. The magnet assembly is configured such that when the moving member moves to a predetermined position, the reed switch senses the magnetic field of the magnet assembly and sends a signal to the control circuit.

[0023] Details of one or more embodiments of the present invention are set forth in the following drawings and description. Other features, objects, and advantages of the present invention will become apparent from the specification, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention, and those of ordinary skill in the art can also obtain the drawings of other embodiments without creative efforts based on these drawings.

[0025] Figure 1 It is a schematic diagram of the principle framework of an injection device according to an embodiment of the present application;

[0026] Figure 2 For Figure 1 It is a schematic diagram of the structural principle of the injection device of the embodiment;

[0027] Figure 3 It is a schematic diagram of the structure of an injection device according to an embodiment of the present application in a state;

[0028] Figure 4 For Figure 3 It is a schematic diagram of the structure of the injection device of the embodiment in another state;

[0029] Figure 5Schematic framework diagram of an injection device according to another embodiment of the present application;

[0030] Figure 6 is Figure 5 Schematic structural diagram of the injection device of the embodiment;

[0031] Figure 7 Schematic framework diagram of an injection device according to another embodiment of the present application;

[0032] Figure 8 is Figure 7 Schematic structural diagram of the injection device of the embodiment. Detailed implementation manners

[0033] To make the above objects, features, and advantages of the present invention more apparent and understandable, the following will describe the detailed implementation manners of the present invention in conjunction with the accompanying drawings. Many specific details are set forth in the following description to fully understand the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0034] In the description of the present invention, it should be understood that terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. may indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0035] In the present invention, unless otherwise clearly defined and limited, terms such as "installation", "connection", "connection", "fixation", "setting", etc. should be understood in a broad sense. For example, unless otherwise clearly defined, "connection" can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and can be the internal communication of two elements or the interaction relationship between two elements. Also, for example, when an element is referred to as "fixed to" or "set on" another element, it can be directly on the other element or there can also be an intermediate element. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] In the present invention, unless otherwise clearly defined or limited, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath" and "underneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the horizontal height of the first feature is less than that of the second feature.

[0037] According to an injection device known to the applicant, it uses mechanical switches such as tactile switches or travel switches to detect the position of a moving part in the injection device, such as the position of a plunger, so as to determine whether the moving part has reached a predetermined position. In this structure, the switch is arranged inside the device housing. When the moving part moves to the predetermined position, the moving part contacts and triggers the switch to transmit a corresponding signal to the corresponding control circuit, thereby realizing the judgment of the position of the moving part. Although the above injection device can realize the position detection of the moving part, its defect is that the switch is arranged inside the device housing, and the signal is transmitted to the control circuit outside the device housing through a signal line, and thus an opening for the line to pass through needs to be opened on the device housing. Therefore, the structure of the injection device described above is relatively complex. At the same time, since the switch is arranged inside the device housing, foreign matters such as liquid from the medicament may flow into the device housing, contact or soak the switch, and thus may cause the switch to malfunction or misoperate. In addition, since an opening needs to be opened on the device housing, foreign matters such as liquid and water vapor may enter the control circuit outside the housing through the opening of the device housing, and thus the function and normal operation of the injection device may be affected.

[0038] One aspect of the present application provides an injection device, which includes a device housing, a control circuit arranged outside the device housing, a moving part located inside the device housing for carrying an injection agent, a magnet assembly located on the moving part and moving together with the moving part, and a magnetic reed switch arranged outside the device housing and connected to the control circuit. The magnet assembly is configured to change the conduction state of the magnetic reed switch when the moving part moves to a predetermined position.

[0039] According to the injection device of the present application, it uses a magnetic reed switch to detect the magnetic field from the magnet assembly to determine the position of the moving part. Since the magnetic reed switch does not need to physically contact the moving part, the magnetic reed switch can be arranged outside the device housing, thereby simplifying the structure of the injection device and reducing the risk of the magnetic reed switch being affected by liquid, water vapor or other foreign matters.

[0040] Figure 1It is a schematic diagram of the principle framework of an injection device 10 according to a specific embodiment of the present application. Figure 2 It is a schematic structural diagram of the injection device 10 of this embodiment. Combining Figure 1 and Figure 2 , in this embodiment, the moving part 30 is located inside the device housing 20, and the control circuit is arranged outside the device housing 20. The magnet assembly 40 is arranged on the moving part 30 and moves together with the moving part 30. The magnetic reed switch 50 is connected to the control circuit to detect the magnetic field emitted by the magnet assembly 40, so as to detect whether the moving part 30 reaches a predetermined position.

[0041] Specifically referring to Figure 2 , according to the illustrated embodiment, the device housing 20 has a longitudinal structure, and an opening 21 for loading an injection agent enclosed in a container ( Figure 2 not shown) is provided at one end, and the other end is closed. The moving part 30 can be driven manually or by a machine in the internal space of the device housing 20 from an initial position ( Figure 2 the position marked by the solid line) to a predetermined position ( Figure 2 the position marked by the dashed line) reciprocally. In one embodiment, the predetermined position can be the position to be injected. When the moving part 30 is in this position to be injected, the injection device 10 enters the state to be injected. It can be understood that in other embodiments, the predetermined position can be other specific positions that need to be detected.

[0042] Figure 3 and Figure 4 are schematic structural diagrams of an injection device 10 of an embodiment. The basic structure and principle of the injection device 10 are existing knowledge in the art and will not be described in detail and completely here, but only the parts closely related to the present application will be described accordingly. At the same time Figure 3 and Figure 4 do not show all the structural features of the product either, but are only used to describe the present invention. Combining Figure 3 and Figure 4 , the moving part 30 includes a plunger 31 and a medicine cartridge 32, wherein the medicine cartridge 32 is used to accommodate a syringe 33. In one embodiment, the magnet assembly 40 is arranged on the plunger 31. However, through the combination of the following description, those skilled in the art can also understand and implement arranging the magnet assembly 40 on the medicine cartridge 32 or other structures of the moving part 30. The magnet assembly 40 is configured according to the technical parameters of the magnetic reed switch 50, such as including magnetism, installation orientation, and installation position, etc., so that when the moving part 30 reaches the predetermined position, the magnetic field intensity of the magnet assembly 40 reaches the opening threshold of the magnetic reed switch 50 to change the conduction state of the magnetic reed switch 50. And when the moving part 30 is far away from the magnetic reed switch 50, for example, when it is in the initial position, the magnetic field of the magnet assembly 40 will not affect the magnetic reed switch 50.

[0043] Continue to refer to Figure 2 , a circuit protection housing 60 is attached to the outside of the device housing 20. A circuit board assembly 70 is provided inside the circuit protection housing 60 to carry a control circuit. The reed switch 50 and other circuit components are connected to the circuit board assembly 70, for example, directly disposed on the circuit board assembly 70 to form a part of the circuit board assembly 70, or in other embodiments, connected to the circuit board assembly 70 in other ways. For example, it is separated from the circuit board assembly 70, but connected to the circuit board assembly 70 through wires or wirelessly. In the illustrated embodiment, the device housing 20 physically isolates the circuit board assembly 70 from the internal space of the device housing 20, so that the control circuit and the reed switch 50 are blocked from the internal space of the device housing 20 and not electrically connected. This can further prevent liquids, water vapor, or other foreign objects inside the device housing 20 from entering the circuit protection housing 60 through the device housing 20 and causing adverse effects on the circuit board assembly 70 and the circuit components thereon. Since there is no need for physical contact between the magnet assembly 40 and the reed switch 50 in this application, in a specific implementation, the position of the device housing 20 corresponding to the circuit protection housing 60 can be a closed structure to prevent foreign objects from entering the circuit protection housing 60. In other embodiments, the reed switch 50 and / or the control circuit can also be buried, for example, by insert molding, in the housing of the device housing 20 or other positions, while being blocked from the internal space of the device housing 20 and not electrically connected, to avoid contact with liquids or other substances entering the internal space of the device housing 20.

[0044] Compared with general mechanical switches, reed switches have a simple structure, small size, high speed, and long working life. At the same time, compared with electronic switches, they have strong anti-load impact ability and high working reliability. The principle and structure of reed switches are existing knowledge in the art and can be directly obtained from the market, such as the MISM-7 series reed switches provided by Littelfuse. Therefore, no further detailed description of reed switches will be given here. In the embodiments of this application, the reed switch 50 can be selected as a normally open type or a normally closed type reed switch. Through corresponding circuit configurations, both types of switches can achieve the required functions.

[0045] Specifically refer to Figure 1, in one embodiment, the control circuit includes a sleep circuit and a working circuit, where the sleep circuit is a low-power circuit and the working circuit is a high-power circuit. The reed switch 50 is connected to the sleep circuit. When the moving part 30 of the injection device 10 does not reach the predetermined position, only the low-power sleep circuit in the control circuit is working, so a lower standby power consumption can be achieved. When the moving part 30 moves to the predetermined position, the magnetic field of the magnet assembly 40 changes the conduction state of the reed switch 50, for example, from open to closed, or from closed to open. Based on the change in the conduction state of the reed switch 50, the sleep circuit wakes up the injection device 10 from the sleep state. For example, in one implementation, the reed switch 50 sends a signal to a controller (not shown) disposed on the circuit board assembly 70 in the control circuit, and the controller wakes up the injection device 10 from the sleep state through the sleep circuit. In some embodiments, waking up from the sleep state includes starting the working circuit to perform self-check of the injection device 10 and powering relevant circuit components. In one embodiment, the working circuit is connected to an indicator, such as an acoustic indicator or an optical indicator, such as an LED indicator. The LED indicator indicates the state of the injection device 10. For example, when the working circuit is started, the LED indicator turns on to convey to the operator the information that the injection device 10 has entered a specific state.

[0046] It can be understood that in other embodiments of the present application, the control circuit may not be divided into a sleep circuit and a working circuit, that is, there is only a single control circuit. When a change in the conduction state of the reed switch 50 is detected, the control circuit starts self-check and powers the corresponding circuit components. Therefore, the specific form of the control circuit does not affect the implementation of judging the state of the injection device 10 through the reed switch 50 and the magnet assembly 40 in the present application.

[0047] Figure 5 is a schematic diagram of the principle framework of the injection device 10 according to another specific embodiment of the present application, Figure 6 is the structural schematic diagram of the injection device 10 in this embodiment. In this embodiment, the injection device 10 further includes a magnetic induction sensor 80. When the moving part 30 moves to the predetermined position, in addition to providing a magnetic field to the reed switch 50, the magnet assembly 40 simultaneously provides a magnetic field to the magnetic induction sensor 80. The magnetic induction sensor 80 is configured to detect the surrounding magnetic field intensity to further confirm that the magnetic field sensed by the reed switch 50 is from the magnet assembly 40.

[0048] During the use of the injection device 10, it may be interfered by an external magnetic field outside the magnet assembly 40, such as a magnetic field from other electronic products. If there is an external magnetic field interference and the magnetic field strength of the external magnetic field is large enough to change the conduction state of the magnetic reed switch 50, the external magnetic field may cause the injection device 10 to be accidentally awakened from the sleep state, even if the moving part 30 does not move to the predetermined position. Therefore, according to Figure 5 and Figure 6 the embodiments shown, the present application further introduces a magnetic induction sensor 80 to confirm the source of the magnetic field, so as to further confirm the position of the moving part 30 and the state of the injection device 10.

[0049] According to a specific embodiment, the control circuit is configured to confirm that the magnetic field sensed by the magnetic reed switch 50 is from the magnet assembly 40 when the magnetic field strength detected by the magnetic induction sensor 80 is within a preset range. The preset range is set based on the magnetic field strength of the magnet assembly 40. For example, under normal circumstances, when the moving part 30 reaches the predetermined position, the magnetic induction sensor 80 will detect a magnetic field strength, and this magnetic field strength can be used as a reference value, with a 10% up and down fluctuation as the preset range. When the actually detected magnetic field strength by the magnetic induction sensor 80 falls within this preset range, it is confirmed that the magnetic field comes from the magnet assembly 40. When the actually detected magnetic field strength exceeds this preset range, for example, the detected magnetic field strength is twice the reference value, it is determined that the magnetic field is an external interference magnetic field. Of course, in actual applications, the preset range can be flexibly adjusted according to the accuracy requirements, such as taking a 3%, 5%, 15% up and down fluctuation of the reference value as the preset range.

[0050] It can be understood that the preset magnetic field strength provided by the magnet assembly 40 to the magnetic induction sensor 80 when the moving part 30 reaches the predetermined position does not have to be a constant and unchanging value. For example, during the implementation operation, when the relative position between the predetermined position of the moving part 30 and the magnetic induction sensor 80 changes, the aforementioned preset magnetic field strength will also have a certain fluctuation. In addition, for example, when the magnetism of the magnet assembly 40 changes, the preset magnetic field strength will also fluctuate accordingly.

[0051] The above-mentioned use of the magnetic induction sensor 80 to detect the magnetic field strength does not mean that the magnetic induction sensor 80 needs to provide an accurate measurement value to the control circuit. For example, in one embodiment, the magnetic induction sensor 80 is a magnetic induction chip with a switching function. When the detected magnetic field is within a specific range, the magnetic induction chip only outputs a switching signal to the control circuit to confirm the source of the magnetic field. Of course, in other embodiments, the magnetic induction sensor 80 can be an analog or digital device, transmitting a specific digital or analog signal reflecting the magnetic field strength to the control circuit, and the control circuit then confirms the source of the magnetic field based on this digital or analog signal.

[0052] For key reference Figure 5 In some embodiments, the magnetic induction sensor 80 is connected to the working circuit. Based on the change in the conduction state of the reed switch 50, the sleep circuit wakes up the injection device 10 from the sleep state and starts the working circuit. At this time, the magnetic induction sensor 80 begins to detect the surrounding magnetic field intensity. As described above, when the detected magnetic field intensity is within the preset range, it is confirmed that the magnetic field comes from the magnet assembly 40, and thus it is confirmed that the moving member 30 reaches the predetermined position. When the detected magnetic field intensity is outside the preset range, it is determined that the magnetic field sensed by the reed switch 50 is an external magnetic field and the working circuit is turned off.

[0053] It can be understood that the magnetic induction sensor 80 can also be directly connected to the sleep circuit. In this configuration, only when both the reed switch 50 and the magnetic induction sensor 80 meet the opening conditions, the sleep circuit will wake up the injection device 10 and start the working circuit. This method can also achieve the secondary confirmation of the position of the moving member 30 through the magnetic induction sensor 80. Of course, as described before, the control circuit may not distinguish between the sleep circuit and the working circuit, but only has a single control circuit. At this time, the magnetic induction sensor 80 is directly connected to the control circuit.

[0054] According to the embodiments described above, the present application further confirms the magnetic field source by providing the magnetic induction sensor 80 to further confirm the position of the moving member 30 and the state of the injection device 10, to a certain extent avoiding the situation that the injection device 10 is woken up by an external magnetic field by mistake.

[0055] In some specific applications, the magnetic induction sensor 80 can be at least one of a Hall sensor or a magnetoresistive sensor. Both the Hall sensor and the magnetoresistive sensor are existing products and can be directly obtained from the market, so no further detailed description will be made here. For example, the Hall sensor can use the Hall sensor with the model AH180 provided by Diodes Incorporated. In addition, the magnetic induction sensor 80 can be directly disposed on the circuit board assembly 70 similar to the reed switch 50, or can be separated from the circuit board assembly 70 and connected by a wire or wirelessly.

[0056] Figure 7 is a schematic diagram of the principle of the injection device 10 according to another specific embodiment of the present application, Figure 8 is a schematic diagram of the structure of the injection device 10 in this embodiment. And Figure 5 and Figure 6The difference in the illustrated embodiment is that the magnet assembly 40 includes a first magnet 41 and a second magnet 42, and the injection device 10 is configured such that when the moving member 30 moves to a predetermined position, the magnetic field of the first magnet 41 acts on the magnetic reed switch 50 but is isolated from the magnetic induction sensor 80, and the magnetic field of the second magnet 42 acts on the magnetic induction sensor 80. The magnetic field of the second magnet 42 can be selectively isolated from the magnetic reed switch 50. In some specific embodiments, the control circuit is configured to confirm that the magnetic field sensed by the magnetic reed switch 50 is from the magnet assembly 40 when the magnetic field intensity detected by the magnetic induction sensor 80 is within a preset range, and to confirm that the magnetic field sensed by the magnetic reed switch 50 is an external magnetic field when the magnetic field intensity detected by the magnetic induction sensor 80 exceeds the preset range. The magnetic induction sensor 80 sets a preset range of magnetic field intensity for confirming the source of the magnetic field according to the second magnet 42. That is, similar to what was described above, under normal circumstances, when the moving member 30 reaches the predetermined position, the magnetic induction sensor 80 detects a magnetic field intensity, which can be used as a reference value, and a specific percentage is floated up and down as the preset range.

[0057] According to the above embodiment, by dividing the magnet assembly 40 into the first magnet 41 and the second magnet 42, and the first magnet 41 corresponding to the magnetic reed switch 50 does not affect the magnetic induction sensor 80, it makes the selection and configuration of the magnetic induction sensor 80 more flexible. For example, when configuring the magnetic induction sensor 80, the attributes of the first magnet 41 do not need to be considered, and at the same time, the position of the magnetic induction sensor 80 can be flexibly adjusted.

[0058] In some embodiments, the first magnet 41 and the second magnet 42 are spaced apart by a preset distance so that the magnetic field of the first magnet 41 is isolated from the magnetic induction sensor 80. The preset distance here can be an actively designed distance, and the corresponding magnet is selected according to this distance, or it can be a distance confirmed according to the magnetic field distribution of the magnet after the magnet is selected. In other embodiments, the injection device 10 may include a magnetic shielding element (not shown), and the magnetic shielding element is configured to isolate the magnetic field of the first magnet 41 from the magnetic induction sensor 80.

[0059] In Figure 5 and Figure 6 's embodiments, when the external magnetic field is similar to the magnetic field of the magnet assembly 40, the external magnetic field changes the conduction state of the magnetic reed switch 50, and at the same time, the magnetic induction sensor 80 cannot determine that the magnetic field is an external magnetic field. Therefore, in this case, the working circuit may still be accidentally awakened. Therefore, in Figure 7 and Figure 8In a further improvement of the illustrated embodiment, the injection device 10 is further configured such that when the moving member 30 moves to a predetermined position, the magnetic field intensity of the second magnet 42 detected by the magnetic induction sensor 80 is lower than the magnetic field intensity required to change the conduction state of the magnetic reed switch 50. In some specific embodiments, the control circuit is configured to confirm that the magnetic field sensed by the magnetic reed switch 50 is from the magnet assembly 40 when the magnetic field intensity detected by the magnetic induction sensor 80 is within a preset range, and to confirm that the magnetic field sensed by the magnetic reed switch 50 is an external magnetic field when the magnetic field intensity detected by the magnetic induction sensor 80 is greater than the preset range. Wherein, the preset range is set based on the magnetic field intensity of the second magnet 42.

[0060] According to the above configuration, the injection device 10 can avoid the possible false wake-up situations in the Figure 5 and Figure 6 embodiments as described above. Since under normal circumstances, when the moving member 30 is at the predetermined position, the magnetic field intensity of the second magnet 42 detected by the magnetic induction sensor 80 is lower than the magnetic field intensity required to change the conduction state of the magnetic reed switch 50. Therefore, once the conduction state of the magnetic reed switch 50 changes, and at the same time the magnetic field intensity detected by the magnetic induction sensor 80 is greater than the preset range, it can be determined that the change in the conduction state of the magnetic reed switch 50 is not due to the magnetic field of the magnet assembly 40, but due to an external interfering magnetic field, that is, it can be presumed that the moving member 30 has not reached the predetermined position. At this time, the working circuit can be turned off.

[0061] It should be noted that the magnetic field intensity of the second magnet 42 being lower than the magnetic field intensity required to change the conduction state of the magnetic reed switch 50 as described above does not necessarily mean that the magnetism of the second magnet 42 is necessarily lower than that of the first magnet 41. Instead, in addition to the inherent properties of the magnets, it is also related to the settings of the magnetic induction sensor 80 and the magnetic reed switch 50, for example, related to the distances between the magnetic induction sensor 80 and the magnetic reed switch 50 and the second magnet 42 and the first magnet 41.

[0062] From the above description, it can be seen that each embodiment of the present application has at least the following technical effects:

[0063] First, by using a magnetic reed switch to replace the traditional switch in the present application, the structural arrangement of the injection device can be improved, and at the same time, the influence of the magnetic reed switch by liquid, water vapor or other foreign objects can be reduced;

[0064] Second, in some embodiments, by using a magnetic induction sensor to further confirm the source of the magnetic field in the present application, to further confirm the position of the moving member and the state of the injection device, thereby reducing the risk of the injection device being falsely awakened to a certain extent;

[0065] Third, in a further embodiment, by dividing the magnet assembly into a first magnet and a second magnet, and at the same time enabling the magnetic induction sensor to only detect the second magnet or the surrounding external magnetic field, the magnetic induction sensor can be more flexible in selection and configuration;

[0066] Fourth, in an even further embodiment, by configuring the first magnet and the second magnet, for example, making the magnetic field intensity of the second magnet lower than the magnetic field intensity required to change the conduction state of the magnetic reed switch, the situation where the injection device is accidentally awakened can be fundamentally avoided.

[0067] The technical features of the above-described embodiments can be combined arbitrarily according to actual situations. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered to be within the scope described in this specification.

[0068] The above-described embodiments only represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the invention patent should be subject to the appended claims.

Claims

1. An injection device, characterized in that, The injection device includes a device housing, a control circuit disposed outside the device housing, a moving member located inside the device housing for carrying an injectant, a magnet assembly located on the moving member and moving together with the moving member, and a reed switch and a magnetic induction sensor disposed outside the device housing and connected to the control circuit; Wherein, the magnet assembly includes a first magnet and a second magnet. The injection device is configured such that when the moving member moves to a predetermined position, the magnetic field of the first magnet acts on the reed switch but is isolated from the magnetic induction sensor. The magnetic field of the first magnet changes the conduction state of the reed switch, and the magnetic field of the second magnet acts on the magnetic induction sensor, and the magnetic field intensity of the second magnet detected by the magnetic induction sensor is lower than the magnetic field intensity required to change the conduction state of the reed switch; Wherein, the reed switch includes a normally open reed switch or a normally closed reed switch.

2. The injection device according to claim 1, characterized in that, The injection device includes a circuit protection housing located outside the device housing and attached to the device housing, and a circuit board assembly carrying the control circuit located inside the circuit protection housing. The reed switch is connected to the circuit board assembly.

3. The injection device according to claim 2, characterized in that, The device housing physically isolates the circuit board assembly from the internal space of the device housing.

4. The injection device according to claim 1, characterized in that, The control circuit includes a sleep circuit. The reed switch is connected to the sleep circuit. When the moving member moves to the predetermined position, based on the change in the conduction state of the reed switch, the sleep circuit wakes up the injection device from the sleep state.

5. The injection device according to claim 1, characterized in that, The control circuit includes a sleep circuit and a working circuit. The reed switch is connected to the sleep circuit, and the magnetic induction sensor is connected to the working circuit. Based on the change in the conduction state of the reed switch, the sleep circuit wakes up the injection device from the sleep state and starts the working circuit.

6. The injection device according to claim 5, characterized in that, The control circuit is configured to confirm that the magnetic field sensed by the reed switch is an external magnetic field and turn off the working circuit when the magnetic field intensity detected by the magnetic induction sensor exceeds a preset range.

7. The injection device according to claim 1, characterized in that, The injection device includes a circuit protection housing located outside the device housing and attached to the device housing, and a circuit board assembly carrying the control circuit located inside the circuit protection housing. The magnetic induction sensor is disposed on the circuit board assembly.

8. The injection device according to claim 1, characterized in that The magnetic induction sensor includes at least one of a magnetoresistive sensor and a Hall sensor.

9. The injection device according to claim 1, characterized in that, The first magnet and the second magnet are spaced apart by a preset distance so that the magnetic field of the first magnet is isolated from the magnetic induction sensor.

10. The injection device according to claim 1, characterized in that, The injection device includes a magnetic shielding element configured to isolate the magnetic field of the first magnet from the magnetic induction sensor.

11. The injection device according to claim 1, characterized in that, The control circuit is configured to confirm that the magnetic field sensed by the reed switch is from the magnet assembly when the magnetic field intensity detected by the magnetic induction sensor is within a preset range, and to confirm that the magnetic field sensed by the reed switch is an external magnetic field when the magnetic field intensity detected by the magnetic induction sensor is greater than the preset range. The preset range is set based on the magnetic field intensity of the second magnet.

12. The injection device according to claim 1, characterized in that, The moving part includes a plunger, and the magnet assembly is arranged on the plunger.

13. The injection device according to claim 1, characterized in that, The predetermined position is the position to be injected.

14. An injection device, characterized in that, The injection device includes a device housing, a moving part that can reciprocate along the length direction of the device housing in the internal space of the device housing during operation, a magnet assembly located on the moving part and moving together with the moving part, a control circuit, and a reed switch and a magnetic induction sensor connected to the control circuit. The control circuit, the reed switch, and the magnetic induction sensor are blocked and non-conductive with the internal space of the device housing; Wherein, the magnet assembly includes a first magnet and a second magnet. The injection device is configured such that when the moving part moves to a predetermined position, the magnetic field of the first magnet acts on the reed switch but is isolated from the magnetic induction sensor. The magnetic field of the first magnet changes the conduction state of the reed switch, the magnetic field of the second magnet acts on the magnetic induction sensor, and the magnetic field intensity of the second magnet detected by the magnetic induction sensor is lower than the magnetic field intensity required to change the conduction state of the reed switch.

15. An injection device, characterized in that, The injection device includes a device housing, a moving part that can reciprocate along the length direction of the device housing in the internal space of the device housing during operation, a magnet assembly located on the moving part and moving together with the moving part, a control circuit, and a reed switch and a magnetic induction sensor connected to the control circuit. The control circuit, the reed switch, and the magnetic induction sensor are blocked and non-conductive with the internal space of the device housing; Wherein, the magnet assembly includes a first magnet and a second magnet. The injection device is configured such that when the moving part moves to a predetermined position, the magnetic field of the first magnet acts on the reed switch but is isolated from the magnetic induction sensor. The reed switch senses the magnetic field of the first magnet and sends a signal to the control circuit. The magnetic field of the second magnet acts on the magnetic induction sensor, and the magnetic field intensity of the second magnet detected by the magnetic induction sensor is lower than the magnetic field intensity required for the reed switch to send a signal.

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