DRUG INFUSION DEVICE WITH ELASTIC ANTI-REVERSAL MEMBER

A drug infusion device with elastic anti-reverse member includes an infusion mechanism module, a control mechanism module, and an adhesive patch. The infusion mechanism module includes a reservoir used for accommodating the drug to be infused, a driving wheel assembly, a driving unit with a driving end that pushes the driving wheel to rotate, a power unit and a reset unit. The driving wheel assembly includes a driving wheel, a driving tube and a cover. The cover is used to fix the driving wheel and also provided with at least one elastic member abutting against the driving wheel assembly. The power unit and the reset unit are connected with the driving unit. The power unit exerts a force on the driving unit to make the driving wheel move forward, and the reset unit exerts a force on the driving unit to reset the driving end.

TECHNICAL FIELD

The present invention mainly relates to the field of medical instruments, in particular to a drug infusion device with elastic anti-reversal member.

BACKGROUND

A drug infusion device is a medical device that achieves the purpose of disease treatment by continuously infusing drugs into the patient's body. Drug infusion devices are widely used in the treatment of diabetes. Insulin is continuously infused into the patient's skin according to the dosage required by the human body, to simulate the secretory function of the pancreas, thereby maintaining the stability of the patient's blood glucose. The drug fluid is usually stored inside the infusion device. In the existing drug infusion device, the infusion device is usually pasted directly on the patient's body through a medical tape, and the patient operates a remote device for infusion.

At present, in an infusion device where a single pawl pushes the gear to rotate and completes drug infusion, it is usually necessary to provide an additional fixed pawl, or two oppositely arranged pawls, or an additional friction component to prevent anti-reversing. At this time, additional pawls or friction components need to be provided in the infusion device making the infusion device with many components and complicated arrange design, thus lowering the space utilization rate inside the infusion device, what's more it cannot offer elastic force to prevent reversing.

Therefore, there is an urgent need for a drug infusion device with a simple arrange desig, high space utilization and can offer elastic force to prevent anti-reversing in prior art.

BRIEF SUMMARY OF THE INVENTION

The invention discloses a drug infusion device with elastic anti-reverse member. At least one elastic member is provided on the drive wheel cover of the infusion mechanism module, abutted against the drive wheel assembly. The elastic member can provide variable elastic friction within a certain range and can better prevent the drive wheel from reversing. The elastic member is provided on cover, thus there is no need for other components to carry it, making full use of the internal space of the infusion device, increasing the compactness of the internal design, and assisting the cover to elastically fix the driving wheel and enhance the user experience.

The invention discloses a drug infusion device with elastic anti-reverse member that includes an infusion mechanism module, that includes: an infusion mechanism module, the infusion mechanism comprising: a reservoir, configured to containing the drug to be infused, and is provided with a screw and a piston connected with the screw; a drive wheel assembly, the driving wheel assembly includes a driving wheel, a driving tube and a cover, the cover is used to fix the driving wheel, and the cover is also provided with at least one elastic member, abutting against the drive wheel assembly; a driving unit with a driving end that pushes the driving wheel to rotate; a power unit and a reset unit connected with the driving unit, the power unit exerts a force on the driving unit to make the driving wheel move forward, and the reset unit exerts a force on the driving unit to reset the driving end; a control mechanism module, electrically connected with the infusion mechanism module, the control mechanism module controls the power unit to apply a force on the driving unit; and an adhesive patch, for attaching the infusion mechanism module and the control mechanism module to the skin surface.

According to one aspect of the present invention, the elastic member is one of a compression spring, a tension spring, and a torsion spring.

According to one aspect of the present invention, one end of the torsion spring is abutted against the driving tube.

According to one aspect of the present invention, the elastic member is an elastic rod.

According to one aspect of the present invention, a groove is provided on the top of the cover, for engaging the elastic rod.

According to one aspect of the present invention, the elastic rod is abutted against the driving tube and/or the side surface of the driving wheel.

According to one aspect of the present invention, the infusion device also includes a frame for carrying the components of the infusion mechanism module, the cover is provided with a plurality of cover engaging portions, and the frame is provided with a plurality of frame engaging portion to engage with the cover engaging portions.

According to one aspect of the present invention, an elastic member is arranged on at least one of the cover engaging portion.

According to one aspect of the present invention, the elastic member is one or more of silicone, rubber, latex, and spring steel.

According to one aspect of the present invention, the silica gel and the cover engaging portion are integrated formed.

According to one aspect of the present invention, the elastic member and the reset unit are the same member.

According to one aspect of the present invention, the infusion mechanism module and the control mechanism module are designed separately, and the control mechanism module can be reused.

According to one aspect of the present invention, the infusion mechanism module and the control mechanism module are disposed of in one housing, discarded together after a single-use.

According to one aspect of the present invention, the adhesive patch comprises a tape and a protective film, the surface of the tape is provided with dense ventilation holes arranged evenly.

Compared with the prior art, the technical solution of the present invention has the following advantages:

In the drug infusion device with elastic anti-reverse member, at least one elastic member is provided on the drive wheel cover of the infusion mechanism module, abutted against the drive wheel assembly. By applying pressure to the drive wheel assembly, the static friction force on the drive wheel can be increased to prevent the drive wheel from reversing. The elastic member can provide variable elastic friction within a certain range and can better prevent the drive wheel from reversing, improving the accuracy of drug infusion and eliminating safety hazards. The elastic member is provided on cover, thus there is no need other components to carry it, making full use of the internal space of the infusion device, increasing the compactness of the internal design, and assisting the cover to elastically fix the driving wheel and enhance the user experience.

Furthermore, the elastic member is a torsion spring, which can provide a wide range of elastic force. At least one end of the torsion spring is abutted against the driving tube, and the abutment position of the other end can be selected according to actual needs, so it can better elastically fix the driving wheel and prevent the driving wheel from reversing.

Furthermore, the elastic member is one or more of compression springs, extension springs, torsion springs, U-shaped elastic rod, L-shaped elastic rod, silicone, rubber, latex, and spring steel. The elastic member's type, quantity, location, layout, such as the position of the elastic member abutted against the driving wheel assembly can be selected according to actual needs, and it is flexible and diverse, and can make full use of the internal space of the infusion device and effectively reduce the volume of the infusion device.

Furthermore, the silica gel and the cover engaging portion are integrated formed, symmetrically abutted on both sides of the drive tube to provide a stable elastic friction force range to prevent the drive wheel from reversing, and at the same time, the driving wheel can be elastically fixed to further reduce the quantity of the components and the volume of the infusion device.

Furthermore, the frame is provided with elastic conductor positioning post, conductive platform positioning post and stopper, conductive tower-spring, and driving unit positioning table, making full use of the internal space, improving the integration of the internal arrangement, and ensuring connection stability and electrical connection reliability of all parts.

Furthermore, the adhesive patch includes a tape and a protective film. The surface of the tape is provided with dense ventilation holes arranged evenly, which makes the tape breathable, and can help the patient to discharge the water vapor and sweat secreted by the skin of the patient, and avoid the water vapor and sweat to soak and crease the patient's skin.

DETAILED DESCRIPTION

As mentioned above, in the infusion device where a single pawl pushes the gear to rotate and completes drug infusion, additional fixed pawl or friction component is needed to prevent driving wheel from reversing, making the infusion device with many components and complicated arrange design, thus lowering the space utilization rate inside the infusion device, and it cannot offer elastic force to prevent reversing.

In order to solve this problem, the present invention provides a drug infusion device with elastic anti-reverse member. At least one elastic member is provided on the drive wheel cover of the infusion mechanism module, abutted against the drive wheel assembly. The elastic member can provide variable elastic friction within a certain range and can better prevent the drive wheel from reversing. The elastic member is provided on cover, thus there is no need for other components to carry it, making full use of the internal space of the infusion device, increasing the compactness of the internal design, and assisting the cover to elastically fix the driving wheel and enhance the user experience

Various exemplary embodiments of the present invention will now be described in detail regarding the figures. The relative arrangement of the components and the steps, numerical expressions and numerical values outlined in the embodiments are not construed as limiting the scope of the invention.

In addition, it should be understood that, for ease of description, the dimensions of the various components shown in the figures are not necessarily drawn in the actual scale relationship; for example, the thickness, width, length or distance of certain units may be exaggerated relative to other mechanism modules.

The following description of the exemplary embodiments is merely illustrative and does not limit its application or use to the invention. The techniques, methods, and devices are known to those of ordinary skill in the art and may not be discussed in detail. However, such techniques, methods, and devices should be considered as part of the specification.

It should be noted that similar reference numerals and letters indicate similar items in the following figures. Therefore, once an item is defined or illustrated in a drawing, it will not be discussed further in the following description of the drawings.

FIG.1aandFIG.1bare schematic top views of the drug infusion device according to two embodiments of the present invention.

In the embodiment of the present invention, the skin patch drug infusion device comprises a control mechanism module100, an infusion mechanism module110and an adhesive patch120, filling module120, which will be described separately below. In other embodiments of the present invention, the patch-type drug infusion device may include more parts, which are not specifically limited here.

The patch-type drug infusion device refers to a tubing-free infusion device that is entirely pasted on the user's skin surface by the one piece of adhesive patch120. And the infusion device is provided with an infusion needle unit121, integrated on the infusion device, instead of a long tube; therefore, the drug can be directly infused from the drug reservoir131to the subcutaneous tissue through the infusion needle unit121.

In the embodiment of the present invention, the infusion mechanism module110and the control mechanism module100are designed separately and connected by a waterproof plug or directly engaged and electrically connected into a whole. Details regarding how the reliability of the electrical connection has been improved when the infusion mechanism module110and the control mechanism module100are directly engaged and electrically connected into a whole will be described below. The infusion mechanism module110can be reused, and the control mechanism module100is discarded after a single use, as shown inFIG.1a. In another embodiment of the present invention, the infusion mechanism module110and the control mechanism module100are connected by a wire and disposed of inside the same housing10. Attached to a certain position of the user's skin by the adhesive patch150, both units will be discarded together after a single use, as shown inFIG.1b.

The patch-type drug infusion device of the embodiment of the present invention includes a control structure100, which receives signals or information from a remote device or a body fluid parameter detection device (such as CGM), and controls the infusion device to infuse drug(s) accordingly.

Inside the housing101of the control structure100are disposed of program modules, circuit board(s) and related electronic units for receiving signals or issuing control instructions, as well as other mechanical units or structures necessary for realizing the infusion function, which is not limited herein. In another embodiment of the present invention, a power supply133can also be provided in the control structure. Preferably, in the embodiment of the present invention, the power supply133is provided in the infusion structure110, which will be described below.

FIG.2aandFIG.2bare schematic views of the control mechanism module according to an embodiment of the present invention.

The control mechanism module100further includes the first electrical contact103exposed on its surface. The first electrical contact103is used as a circuit connection terminal to connect the internal circuits provided in the control mechanism module100and the infusion mechanism module110, respectively. The embodiment of the present invention does not specifically limit the positions of the first electrical contact103.

Compared with the plug connector used as a connection terminal in the prior arts, the contact area of the electrical contact is much smaller, which provides more flexibility to the mechanism module design, and can effectively reduce the volume of the control mechanism module. At the same time, these smaller electrical contacts can be directly connected to the internal circuit or electrical components. They could also be directly soldered on the circuit board, which helps to optimize the design of the internal circuit and effectively reduce the complexity of the circuit, thereby saving costs and reducing the volume of the infusion system. Furthermore, the electrical contacts are exposed on the surface of the control mechanism module100to facilitate electrical connection with connection ends on other mechanism modules.

The type of the first electrical contact103includes rigid metal pins or elastic conductive members. Preferably, in the embodiment of the present invention, the first electrical contact103is a rigid metal pin. One end of the first electrical contact103is electrically connected to the connection end provided inside the control mechanism module100. In contrast, the other end is exposed on the surface of the lower housing101b. The rest part of the first electrical contact103is tightly embedded in the housing101, thus keeping the internal control mechanism module100isolated from the outside.

The elastic conductive member includes conductive spring, conductive silica gel, conductive rubber, or conductive leaf spring. One end of the elastic conductive member is used to electrically connect with the internal connection end in the control mechanism module100, while the other end is used to connect with other connection ends electrically.

As in an embodiment of the present invention, the first electrical contact103is a conductive spring. When the electrical contacts are in contact with each other, the elasticity of the conductive spring can enhance the reliability of the electrical connection. Similar to the rigid metal pin, one end of the conductive spring is exposed on the surface of the lower housing101b. In contrast, the remaining part of the conductive spring is tightly embedded in the housing101and electrically connected with internal circuits or electrical components. The connection end disposed inside the control mechanism module100can be a conductive lead, a specific part of a circuit, or an electrical element.

It should be noted that the “tightly embedded” in the embodiment of the present invention suggests that there is no gap between the electrical contact and the housing101, keeping the control mechanism module100tightly sealed. The following “tightly embedded” has the same meaning as here.

In another embodiment of the present invention, the first electrical contact103is a conductive spring, but it is not tightly embedded in the housing101. Instead, a sealing element is provided in a groove, both of which are disposed around the area where the first electrical contacts103are located, thus sealing the electrical contact area and the control mechanism module100.

In the embodiment of the present invention, the control mechanism module100is further provided with the first engaging portions102, which is used to fasten the second engaging portion112disposed on the infusion mechanism module110to assemble the control mechanism module100infusion mechanism module110. Details regarding how the mechanism works to enable the electrical connection between the first electrical contacts103and the second electrical contacts113(as shown inFIG.2aandFIG.2b) will be described below.

The first engaging portion102and the second engaging portion112include one or more hooks, blocks, holes, and slots that can be engaged with each other. The positions of the hooks, blocks, holes, and slots can be flexibly adjusted, according to the shape and mechanism module features of the control mechanism module100and the infusion mechanism module110, such as disposed in the interior or on the surface of the corresponding mechanism module, which is not specifically limited herein.

In the embodiment of the present invention, the control mechanism module100is further provided with a concave104that fits the convex portion114disposed at the bottom of the case of the infusion mechanism module110, which will be described in detail below. Preferably, the first electrical contacts103are provided in the concave104, as shown inFIG.2b.

In the embodiment of the present invention, a buzzer (not shown) is also provided in the control structure100. When the infusion process starts or ends, the infusion device malfunctions, the drug is exhausted, the control structure100issues an error command or receives an error message, etc., the buzzer is used to issue alarm signals, such as sound or vibration, notifying the user to adjust or replace the device in time.

Preferably, in the embodiment of the present invention, the housing101of the control structure100is provided with a sound-permeable outlet105to allow the sound alarm signal from the buzzer to be sent out. In order to achieve a good sealing effect and ensure the normal operation of the buzzer, a waterproof sound-permeable membrane (not shown) is disposed between the sound-permeable outlet105and the buzzer. Therefore, the waterproof sound-permeable membrane needs to have a certain porosity to ensure the sound transmission but prevent water molecules penetration.

Compared with the traditional technical solution in which the buzzer is entirely enclosed in the control structure100, because of the sound-permeable outlet105, a less loud sound signal emitted from the buzzer would be enough to raise the user's attention, which reduces the energy consumption of the buzzer, thereby optimizing the power consumption configuration of the infusion device and saving production costs.

FIG.3ais a schematic view of the infusion mechanism module110according to the embodiment of the present invention.FIG.3bis a side view of the assembly of the control mechanism module100and the infusion mechanism module110according to the embodiment of the present invention.FIG.3cis a schematic top view of the lower case of the infusion mechanism module according to an embodiment of the present invention.FIG.3dis a schematic top view of the lower case of the infusion mechanism module according to another embodiment of the present invention.

The skin patch drug infusion device further includes an infusion mechanism module110with a case. A mechanical module, an electric control module, and other auxiliary modules for completing the drug infusion process are provided inside the case, which will be described in detail below. The case of the infusion mechanism module110may include multiple parts. As in the embodiment of the present invention, the case of the infusion system includes an upper case111aand a lower case111b.

As mentioned above, in the embodiment of the present invention, the infusion mechanism module110is provided with the second engaging portions112, which is used to engaged and fasten the corresponding first engaging portions102. The positions where the first engaging portions102and the second engaging portions112are provided correspondingly.

In the embodiment of the present invention, the infusion structure110is provided with second electrical contacts113, which are used to press against the corresponding first electrical contacts103to create an electrical connection between the control structure100and the infusion structure110. The compression between these two corresponding electrical contacts disposed on different structures can improve the reliability of the electrical connection. Similar to the first electrical contacts103, one of the second electrical contact113also includes a rigid metal pin and an elastic conductive member. Preferably, in the embodiment of the present invention, the second electrical contact113is a conductive spring. Similarly, the conductive spring can improve the electrical connection performance. A groove is also arranged around the area where the second electrical contact113is disposed, and a sealing member115is arranged in the groove. Similarly, the elasticity of the conductive spring can further improve the electrical connection performance.

Preferably, in the embodiment of the present invention, the two ends of the conductive spring have different diameters. And the diameter of the end exposed to the outside of the infusion mechanism module110is shorter than that of the end inside the infusion mechanism module110. In this way, the conductive spring can be held in the case because of the longer diameter; Thus, when the control mechanism module100is not installed on the infusion mechanism module110, the longer diameter of the inner end can prevent the conductive spring from detaching from the infusion mechanism module110.

The embodiment of the present invention does not limit the position at where second electrical contacts113are arranged, as long as it can be electrically connected to the corresponding first electrical contacts103. Preferably, in the embodiment of the present invention, the upper case111aof the infusion mechanism module110includes a convex portion114where the second electrical contacts113are disposed, as shown inFIG.3a. The shape of the convex portion114corresponds to that of the concave104disposed on the control mechanism module100, allowing the two portions to tightly fit each other and press the first electrical contacts103and the corresponding second electrical contacts113against each other to realize the electrical connection.

In other embodiments of the present invention, the convex portion114may be provided on the lower case111b. When the infusion mechanism module110includes an integral case, the convex portion114will be a part of the integral case not specifically limited herein.

The method of assembling the control mechanism module100and the infusion mechanism module110to each other includes pressing the control mechanism module100on the infusion mechanism module110along the thickness direction of the infusion mechanism module110, thereby engaging the first engaging portion102and the second engaging portion112; or pressing the control mechanism module100on the infusion mechanism module110along the length direction of the infusion mechanism module110. Alternatively, the control mechanism module100can be pressed along with any angle between the thickness direction and the length direction of the infusion mechanism module110, making the first engaging portion102and the second engaging portion112engaged with each other. Preferably, in the implementation of the present invention, the method by which the control mechanism module100and the infusion mechanism module110are assembled is to press the control mechanism module100on the infusion mechanism module110along with the thickness direction of the infusion mechanism module110, making the first engaging portion102and the second engaging portion112engaged with each other, as shown the installation direction inFIG.3b.

In the embodiment of the present invention, the lower case111bof the infusion mechanism module110further includes an outward extending portion116. A block117is provided outside the outer extending portion116, as shown inFIG.3a. As mentioned above, the control mechanism module100is pressed to the engaging position along the thickness direction of the infusion mechanism module110; thus, block117can prevent the control mechanism module100from detaching along the length direction of the infusion mechanism module110, ensuring the normal operation of the infusion system. Obviously, in another embodiment of the present invention, if the control mechanism module100is pressed to the engaging position along with other directions, the control mechanism module100can also be prevented from detaching from the infusion mechanism module110by adjusting the position of the block117.

It should be noted here that “outer” and “outside” are relative to the main body of the infusion mechanism module110, where they belong to a concept of the relative position, as shown inFIG.3aorFIG.3b. The “outside” below have the same meaning as here.

In the embodiment of the present invention, the outer end of the outer extending portion116is also provided with a pressing portion118for releasing the blocking effect of block117. While the user is replacing the infusion mechanism module110, the control mechanism module100can be released from block117by pressing the pressing portion118with a finger. Then, the user can remove the control mechanism module100from the infusion mechanism module110with two fingers.

Another embodiment of the present invention can also be provided with an unlocking hole119disposed of in the inner side of block117. While the pressing portion118is pressed, a finger can enter the unlocking hole119, thereby pushing the control mechanism module100out to separate the control mechanism module100from the infusion mechanism module110. In the embodiment of the present invention, the unlocking hole119is square. The square unlocking hole119can facilitate the smooth entry of fingers. In other embodiments of the present invention, the unlocking hole119may also have other shapes, which is not specifically limited here.

The lower case111bof the infusion mechanism module110is also provided with one or more crease grooves140. Two crease grooves140are provided on both sides of the unlocking hole119, as shown inFIG.3candFIG.3d. After the crease groove,140is provided, the thickness or width of the lower case111bat the crease groove140(as shown by the arrows inFIG.3candFIG.3d) is reduced. When the user presses the pressing portion118, the lower case111bis easily broken at the crease groove140, and the blocking of the control mechanism module100by block117is more smoothly released.

Preferably, in the embodiment of the present invention, two crease grooves140are provided at the both ends of block117, respectively, as shown inFIG.3c. In another embodiment of the present invention, the crease groove140is provided on two corresponding lateral sides of the unlocking hole119, as shown inFIG.3d.

The skin patch drug infusion device further includes a needle unit121, used for infusing the drug to the subcutaneous tissue.

An adhesive patch120is also provided on the bottom of the lower case111bto attach the infusion device to the user's skin surface. The adhesive patch includes a tape and a protective film. The surface of the tape is provided with dense ventilation holes arranged evenly, which makes the tape breathable, and can help the patient to discharge the water vapor and sweat secreted by the skin of the patient, and avoid the water vapor and sweat to soak and crease the patient's skin.

FIG.4aandFIG.4bare two schematic views of the internal mechanism module130of the infusion mechanism module110of the embodiment of the present invention from two perspectives, respectively.FIG.4cis a schematic view of the internal mechanism module130of the infusion mechanism module according to another embodiment of the present invention.

In the embodiment of the present invention, the internal mechanism module130includes mechanical units and electronic control units used to realize the infusion function, such as a drug reservoir131, a drug outlet132, a power supply133, a driving wheel134, a screw135, a circuit board (not shown), a driving unit1310, etc. The movement of the driving unit1310drives the driving wheel134to rotate, thus making the screw135push the piston312(as shown inFIG.14) in the drug reservoir131forward, realizing the drug infusion.

In the embodiment of the present invention, the power supply133is a conventional button battery. In other embodiments of the present invention, the power supply133may also be other types of batteries, as long as it can meet the requirements for supplying power to the infusion system. Preferably, in the embodiment of this present invention, the type of the power supply133is a double-row battery pack; that is, two rows of button batteries are arranged on both sides of the driving wheel134, respectively, as shown inFIG.4b. Conventionally, the discharge capacity of button batteries is low. The double-row button battery pack can reduce the discharge level of each battery, thereby extending the service life of the battery. Furthermore, the double-row design of the power supply133can make the full use of the internal space and improve the integration within the internal mechanism module in the infusion system.

The infusion mechanism module110in the embodiment of the present invention is also provided with a circuit board or multiple three-dimensional circuits coated on the surface of a part of the mechanism module for supplying power to specific structural units. According to the internal arrangement characteristics of the infusion device, the shape and position of the three-dimensional circuit can be flexibly designed, which can make the full use of the internal space of the infusion mechanism module, making the arrangement more compact. The circuit board is a hard/rigid circuit board or a flexible circuit board. Preferably, in the embodiment of the present invention, the circuit board is flexible. The shape of the flexible circuit board is adjustable, allowing it to be flexibly designed according to the internal space of the infusion mechanism module110. At the same time, multiple connection ends can be provided on the flexible circuit board to be electrically connected to second electrical contacts113, thereby connecting the circuits of the control mechanism module100and the infusion mechanism module110, allowing the infusion system to perform drug infusion function.

An elastic conductor136is also provided inside the infusion mechanism module130. The elastic conductor136is electrically connected to the power supply133, and the specific connection end on the circuit board (or three-dimensional circuit), thereby supplying power to specific structural units.

FIG.5is a schematic view of the elastic conductor according to an embodiment of the present invention.

In the embodiment of the present invention, the elastic conductor136includes a first elastic conductor136aand a second elastic conductor136b, the first elastic conductor136ais connected with the power supply133, and the second elastic conductor136bis connected with the specific connection end on the circuit board (or three-dimensional circuit). At least a protrusion1361is provided on the first elastic conductor136aand the second elastic conductor136b, which facilitate the point contact connection or the line contact connection between the first elastic conductor136aand the power supply133, and also facilitate the point contact connection or the line contact connection between the second elastic conductor136band the specific connection end on the circuit board (or three-dimensional circuit), thereby improving the electrical connection reliability between the elastic conductor136and the power supply133, and the specific connection end on the circuit board (or three-dimensional circuit). When the first elastic conductor136aand the second elastic conductor136bis flat, during use, it is likely to cause a poor connection between the elastic conductor136and the power supply133and the specific connection end on the circuit board (or three-dimensional circuit), thereby affecting the use effect. In the embodiment of the present invention, protrusion1361may be a linear protrusion formed by bending the first elastic conductor136aor the second elastic conductor136b, or it may be several dots or other shapes of protrusions formed by other means on the first elastic conductor136aor the second elastic conductor136b. The form and number of the protrusions1361on the first elastic conductor136aor the second elastic conductor136bcan be the same or different. Here, the form, number, and forming method of the protrusions1361are not specifically limited, as long as the point contact connection or line contact connection between the elastic conductor136and the power supply133and the specific connection end on the circuit board (or three-dimensional circuit) can be enhanced, improving the reliability of the electrical connection.

In the embodiment of the present invention, the first elastic conductor136aand the second elastic conductor136bare approximately arranged in an “L” shape, the first elastic conductor136ais approximately parallel to the frame137, and the second elastic conductor136bis approximately perpendicular to the frame137. In other embodiments of the present invention, the first elastic conductor136aand the second elastic conductor136bcan also be arranged in other shapes, which are not specifically limited here, as long as the power supply133and the specific connection end on the circuit board (or three-dimensional circuit) can be electrically connected. An insulating member1362is also provided at the junction of the first elastic conductor136aand the second elastic conductor136b(as shown at the position L inFIG.5) to prevent the power unit1311from contacting the elastic conductor136and causing a short circuit during operation, further stop the infusion mechanism module130from working. In the embodiment of the present invention, the insulating member1362is formed by printing ink. In other embodiments of the present invention, the insulating member1362may also be insulating glue, insulating varnish or insulating material, which is not specifically limited herein.

In the embodiment of the present invention, the elastic conductor136may be a sheet metal including the first elastic conductor136aand the second elastic conductor136bor may be intergrated by the single first elastic conductor136aand the single second elastic conductor136bwhich are directly electrically connected or indirectly electrically connected with other conductive elements, which is not limited herein. When the elastic conductor136is a sheet metal including the first elastic conductor136aand the second elastic conductor136b, which not only make the elastic conductor136with simple technological process, firm connection between the elastic conductor136aand the second elastic conductor136b, but also reduce the volume of the elastic conductor136, save the material and the raw material and technological cost. When the elastic conductor136is intergrated by directly electrically connecting the first elastic conductor136aand the second elastic conductor136bor indirectly electrically connected with other conductive elements, the elastic member can be flexibly selected according to the requirements of the specific connecting components to optimize the internal design of the infusion mechanism module.

In the embodiment of the present invention, the frame137is further provided with a positioning post138, the elastic conductor136is provided with an opening corresponding to the positioning post138, and the elastic conductor136is sleeved on the positioning post138through the opening, so that the elastic conductor136is fixed to the frame137. At the same time, the positioning post138is melted by hot melting to further fixed the elastic conductor136and to prevent the elastic conductor136from shaking due to long-term use or other reasons, which cause the poor electric connection between the elastic conductor136and the power supply133and the specific connection end on the circuit board (or three-dimensional circuit) and affect the use.

In the embodiment of the present invention, a boss139is also provided on frame137. The boss139is located below the first elastic conductor136ato prevent the protrusion1361of the first elastic conductor136afrom being flattened or deformed during long-term use, which results in a poor electrical connection between the first elastic conductor136aand the specific connection end on the circuit board (or three-dimensional circuit), causing a malfunction. Preferably, the setting position of the boss139deviates from the projection position of the protrusion1361on the frame137and is close to the position post138. On the one hand, it can prevent the circuit board from being damaged by hard contact or compression between the first elastic conductor136aand the specific connection end on the circuit board (or three-dimensional circuit). On the other hand, it can ensure the elastic electrical contact between the first elastic conductor136aand the specific connection end on the circuit board (or three-dimensional circuit).

Similar to the elastic conductive member above mentioned, the type of the elastic conductor136includes a conductive spring, a conductive leaf spring, a conductive rubber, a conductive silica gel, etc., which are not specifically limited herein, as long as they can meet the requirements for electrically connecting the power supply133to specific connection ends on the circuit board (or three-dimensional circuit). Preferably, in the embodiment of the present invention, the elastic conductor136is the conductive leaf spring. Since the infusion mechanism module110has a double-row battery pack, the multiple conductive leaf springs are also designed as a double-row pack, as shown inFIG.4a.

As shown inFIG.4a, the interior of the infusion mechanism module110also includes a drive unit1310and a power unit1311, arranged on the frame137. Frame137is also provided with a rotation shaft1313, the drive unit1310is provided with a through hole, and the drive unit1310is sleeved on the rotation shaft1313through a through hole for fixing. The elastic conductor136can realize a direct electrical connection between the power supply133and the specific structural units, which helps to optimize the internal circuit design and reduce the complexity of the internal mechanism module. The driving unit1310includes a driving end1312. One end of the power unit1311is connected to the driving unit1310, and the other end is connected to a specific connection ends on the circuit board or three-dimensional circuit through the conductive platform1314so as to further realize the connection with the control module in the control mechanism module100. The control module in the control mechanism module100applies power to the power unit1311, the drive unit1310rotates around the rotation shaft1313, drives the drive end1312forward to push the gear teeth of the drive wheel134forward, and causes the infusion device to perform drug delivery. In the embodiment of the present invention, there are two driving ends1312and two corresponding power units1311. In another embodiment of the present invention, there is one driving end1312and one power unit1311, as shown inFIG.4c.

The infusion mechanism module110is also provided with a conductive tower-spring1315sleeved on the rotating shaft1313, with one end abuts the drive unit1310, and the other end electrically connected to a specific connection end on the circuit board or three-dimensional circuit for fixing the drive unit1310, at the same time, realize the electrical connection between the driving unit1310and specific connection ends on the circuit board or three-dimensional circuit.

FIG.6is a schematic view of the conductive tower-spring according to an embodiment of the present invention.

In the embodiment of the present invention, the conductive tower spring1315includes a part A with a small diameter at the central part in the axial direction and a part B and a part C with a large diameter at both ends. The diameter of part A remains the same, and the rotation shaft1313is fixed by interference fit, further, fix the drive unit1310, and at the same time, part B abuts the drive unit1310to prevent the drive unit1310from shaking due to instability when it is accidentally touched, causing the drive end1312to push the drive wheel134forward, which affects the accuracy of the infusion. The diameter of the B part and the C part gradually expand towards the two ends in a horn-like shape. When the B part and the C part are respectively electrically connected to the drive unit1310and the specific connection ends on the circuit board or three-dimensional circuit, the conductive tower-spring1315is compressed; therefore, part B and part C have multiple turns, and at least 2-3 turns of springs are in contact with the driving unit1310and the specific connection ends on the circuit board or three-dimensional circuit at the same time, thereby improving the electrical connection reliability of the infusion device. Preferably, in the embodiment of the present invention, parts B and C of the conductive tower-spring1315are symmetrical, and the two ends can be assembled at will to avoid assembly misalignment.

FIG.7is a partially enlarged view of the part M portion inFIG.4aaccording to the embodiment of the present invention.

In the embodiment of the present invention, at least one conductive platform1314is provided inside the infusion mechanism module110. Specifically, when the driving unit1310includes two driving arms1312, there are two corresponding power units1311and conductive platforms1314, as shown inFIG.4a. When the driving unit1310includes one driving arm1312, there is one corresponding power unit1311and one conductive platform1314, as shown inFIG.4c. The conductive platform1314is electrically connected to the power unit1311and the specific terminal on the circuit board or three-dimensional circuit, respectively.

The conductive platform1314includes a conductive platform body141and a conductive arm142. The conductive arm142is an elastic conductive element. At least one conductive platform protrusion1421is provided on the conductive arm142to facilitate the connection with specific connection ends on the circuit board (or three-dimensional circuit), improving the electrical connection reliability of the conductive platform1314and the specific connection ends on the circuit board (or three-dimensional circuit). When the conductive arm142of the conductive platform1314is flat, it is likely to cause the poor connection between the conductive platform1314and specific connection ends on the circuit board (or three-dimensional circuit) during use, thereby affecting the use effect. In the embodiment of the present invention, conductive platform protrusion1421may be a linear protrusion formed by bending conductive arm142, or it may be several dots or other shapes of protrusions formed by other means on conductive arm142. Here, the form, number, and forming method of conductive platform protrusion1421are not specifically limited, as long as the point contact connection or line contact connection between the conductive platform1314and the specific connection ends on the circuit board (or three-dimensional circuit) can be enhanced, improving the reliability of the electrical connection. In the embodiment of the present invention, the conductive platform body141further includes an end portion1411of the conductive platform body, and the power unit1311is an electric drive type linear driver or an electric heating type linear driver, such as a shape memory alloy, which is connected to the conductive platform body141by die casting, causing stable connection and highly reliable electrical connection. Specifically, the power unit1311is put into the end portion1411of the conductive platform body after being folded in half and then connected to the end portion1411of the conductive platform body141by die-casting method further improving the reliability of the electrical connection.

In the embodiment of the present invention, the conductive platform1314may be a sheet metal including the conductive platform body141and conductive arm142, or may be formed by the single conductive platform body141and the single conductive arm142directly electrically connected or indirectly electrically connected with other conductive elements, which is not limited herein. When the conductive platform1314is a sheet metal including the conductive platform body141and the conductive arm142, which not only make the conductive platform1314with simple technological process, firm connection between the conductive platform body141and conductive arm142, but also reduce the volume of the conductive platform1314, save the material and the raw material and technological cost. When the conductive platform1314is integrated by the single conductive platform body141and the single conductive arm142directly electrically connected or indirectly connected with other conductive elements, the conductive member can be flexibly selected according to the requirements of the specific connecting components to optimize the internal design of the infusion mechanism module.

Similarly, the conductive platform body141and the conductive platform body end portion1411can also be sheet metal or integrated by directly or indirectly electrically connecting with other conductive elements, which is not limited herein. The conductive platform1314is a sheet metal including the conductive platform body141, the conductive arm142and the conductive platform body end portion1411, or the two of them can be a sheet metal and then integrated with the third party directly or indirectly through other conductive elements, or all of the three parts are directly integrated or indirectly integrated by electrical connection with other conductive elements, and there is no specific limitation here. The benefits of various forming methods are described above, so it will not be repeated here. Preferably, in the embodiment of the present invention, the conductive platform body141, the conductive arm142and the conductive platform body end portion1411are integrally formed.

In the embodiment of the present invention, a plurality of stoppers1316are provided on the frame137for accommodating and limiting the position of the conductive platform1314, the frame137is further provided with a conductive platform positioning post1317, the conductive platform1314is provided with an opening corresponding to the conductive platform positioning post1317, and the conductive platform1314is sleeved on the conductive platform positioning post1317through the opening, so that the conductive platform1314is fixed to the frame137. At the same time, the conductive platform positioning post1317is melted by hot melting to further fixed the conductive platform1314and to prevent the conductive platform1314from shaking due to long-term use or other reasons, which cause the poor electric connection between the conductive platform1314and the power supply133and the specific connection end on the circuit board (or three-dimensional circuit) and affect the use.

In the embodiment of the present invention, a conductive platform boss (not shown) is also provided on the frame137, and the conductive platform boss is located below the conductive arm142to prevent the conductive platform protrusion1421of the conductive arm142from being flattened or deformed during long-term use, which results in a poor electrical connection between the conductive arm142and the specific connection end on the circuit board (or three-dimensional circuit), causing a malfunction. Preferably, the setting position of the conductive platform boss deviates from the projection position of the conductive platform protrusion1421on the frame137and it is close to the conductive platform positioning post1317. On the one hand, it can prevent the circuit board from being damaged by hard contact or compression between the conductive arm142and the specific connection end on the circuit board (or three-dimensional circuit). On the other hand, it can ensure the elastic electrical contact between the conductive arm142and the specific connection end on the circuit board (or three-dimensional circuit).

Similar to the elastic conductor136above mentioned, the type of the conductive platform1314includes a conductive spring, a conductive leaf spring, a conductive rubber, a conductive silica gel, etc., which are not specifically limited herein, as long as they can meet the requirements for electrically connecting the power unit1310to specific connection ends on the circuit board (or three-dimensional circuit).

FIG.8aandFIG.8bare schematic views of the driving wheel assembly and the frame before and after assembly according to the embodiment of the present application embodiment, respectively.FIG.8cis a schematic view of the shield according to an embodiment of the present invention.

The driving wheel assembly includes a driving wheel body16and a movable block18. The driving wheel body16includes a driving wheel161, a driving tube162, which is provided with threads for accommodating the screw135, and a connecting piece163arranged at the end of the driving wheel161. The connecting piece163is provided with a connecting portion1631, operatively connected with the movable block18. The movable block18is provided with threads to accommodate the screw135. The movable block18is also provided with a movable block connecting rod181, which is mobily connected with the connecting portion1631. After the connecting rod181is mobily connected with the connecting portion1631, the movable block18can rotate around the connecting rod181to open or close the movable block18. When the movable block18is opened, the screw135can slide to the driving wheel body16, and when the movable block18is closed, the screw135cannot slide to the driving wheel body16, which will be described in detail below.

The driving wheel assembly further includes a shield15, and a plurality of shield engaging portions151are provided on the shield15for engaging with the frame17. The frame17is provided with a frame groove171for accommodating the driving wheel body16and a plurality of frame engaging portions172for engaging with the shield engaging portions151. After the driving wheel body16and the movable block18are connected and put into the frame groove171, the shield15is assembled to the frame17. By the engagement of the frame engaging portion173and the shield engaging portion151, the driving wheel body16and the movable block18are fixed in the frame17to prevent the shaking of the driving wheel assembly and affect the accuracy of drug infusion.

The frame engaging portions173and the shield engaging portion151include hooks, blocks, holes, and grooves that can be engaged with each other. The position of the engaging portions can be flexibly designed according to the shape and design of the frame17and the shield15, and is not specifically limited here. Preferably, the space formed by the plurality of frame engaging portions173and the plurality of shield engaging portions151can accommodate the driving wheel body16and the movable block18to prevent the driving wheel body16from shaking.

In the embodiment of the present invention, the shield15is also provided with at least one elastic arm152for elastically abutting the drive tube162, which can further fix the drive wheel body16, improving the stability of the infusion mechanism module110and the accuracy of drug infusion. Preferably, two elastic arms152are arranged on both sides of one of the driving wheels161and abut against the driving tube162, respectively. As shown inFIG.8b, the driving wheel body16is fixed at multiple points.

The shield15is also provided with a baffle153, and the baffle153is provided with a mouth. The main frame17is also provided with a card slot173on the side close to the reservoir131for accommodating the strip (not shown). The strip abuts against the baffle153to form a through hole for accommodating the screw135and at the same time confine the driving wheel body16and the movable block18in the frame17. Preferably, the mouth of the baffle153is semi-circular, and the diameter is adapted to the diameter of the screw135, so as to better accommodate the screw135and prevent the screw135from shaking greatly under the action of external force.

Preferably, in the embodiment of the present invention, the shield15is integrally molded; the technological process is simple, the volume is small, the connection is firm, the material is saved, and the cost is reduced.

FIG.9a-FIG.9dare schematic views of the movable block opened or closed according to an embodiment of the present invention, respectively.

The movable block18further includes an upper movable block182and a lower movable block183, and the lower movable block183is also provided with a lower movable block end1831. The movable block18opened means that the upper movable block182is close to the driving wheel161, and the lower movable block183is far away from the driving wheel161. The thread in the movable block18does not engage with the screw135. The screw135can be smoothly slid in the movable block18and the driving tube162. The movable block18closed means that the upper movable block182is far away from the driving wheel161, and the lower movable block183is close to the driving wheel161. At this time, the thread in the movable block18is engaged with the screw rod135, and the screw135cannot slide in the movable block18and the driving tube162.

In the embodiment of the present invention, an arc-shaped blocking member174is also provided on the frame17to limit the position of the lower movable block183. When the movable block18is opened, that is, the upper movable block182is close to the driving wheel161and the lower movable block183is far away from the driving wheel161, the lower movable block end1831of the lower movable block183is located outside the arc-shaped blocking member174, so that the movable block183is kept open. At this time, the thread in the movable block18does not engage with the screw135, and the screw135can slide smoothly in the movable block18and the drive tube162. When the movable block18is opened, the reservoir131can be filled with the drug. In the filling process to the reservoir131, the screw135can smoothly move to the end of the driving wheel161under the pushing action generated during the filling process, until the filling is completed, no need for the assistance of other parts, which can simplify the complexity of the infusion mechanism module, improve the integration level, save cost, and reduce the volume of the infusion mechanism110, and at the same time maximizing the actual storage volume of reservoir131.

When the movable block18is closed, that is, the movable block182is far away from the driving wheel161and the lower movable block183is close to the driving wheel161, the lower movable block end1831of the lower movable block183is located inside the arc-shaped blocking member174, and the movable block18is kept closed. At this time, the thread in the movable block18is engaged with the screw135, and the screw135cannot slide in the movable block18and the drive tube162. When the infusion device110performs the drug infusion after the drug is filled, the driving end1312of the driving unit1310pushes the driving wheel161forward, and the movable block18rotates with the driving wheel161. During the rotation, after the lower movable block end1831bypasses the arc-shaped blocking member174, since there is no resistance from the arc-shaped blocking member174, the lower movable block end1831falls into the inside of the arc-shaped blocking member174. At the same time, since the movable block18is kept closed, the screw135can only move away from the driving wheel161under the pushing action of the rotation of the driving wheel161and perform the drug infusion. There is no need to worry about the free movement of the screw135due to the engagement failure of the screw135with the movable block18or the drive tube162, which will affect the infusion effect or even cause the infusion device to disable.

In the embodiment of the present invention, a notch1611is provided on the end face of the driving wheel16, close to the reservoir131, the shape is adapted to the lower movable block183, and is used for accommodating the lower movable block183. When lower movable block end1831bypasses the arc-shaped stopper174and falls into the inside of the arc-shaped stopper174, the lower movable block183is accommodated in the notch1611of the driving wheel161, making full use of the space of the driving wheel body, optimizing the internal design of the infusion mechanism module to reduce the volume of the infusion device.

It should be noted here that “inside” and “outside” are relative to the arc-shaped blocking member174, and belong to the concept of relative position. The positional relationship is as shown inFIG.9bandFIG.9d.

FIG.10a-FIG.10care schematic views of the elastic element and the driving wheel assembly according to the embodiment of the present application.FIG.10dis a partially enlarged view of the N region ofFIG.10b.

In the infusion device where a single pawl pushes the gear to rotate and completes drug infusion, as shown inFIG.4c, the pressure exerted by the driving end1312on the driving wheel134is not uniform at different positions due to the gear teeth and the circumference of the driving wheel134. Therefore, when the power unit1311applies power to the driving end1312, the driving end1312can push the gear teeth to rotate the driving wheel, thereby realizing drug infusion. When the reset unit1320applies power to the driving end1312, the driving end1312performs a reset motion, where the drive end1312stops pushing the gear, and slides on the surface of the gear teeth. At this time, the drive wheel may rotate in the forward direction or the reverse direction.

In the embodiment of the present invention, the power unit1311includes an electrically powered linear driver or an electrically heated linear driver. Specifically, the power unit1311is a shape memory alloy. The reset unit1320includes an electrically driven linear actuator, an electrically heated linear actuator, or an elastic member. The types of elastic members include, but are not limited to, compression springs, extension springs, torsion springs, elastic sheets, elastic plates, elastic rods, elastic rubbers, and the like. The elastic member can automatically spring back the driving end1312to the original position without external force. Specifically, in the embodiment of the present invention, the reset unit1320is a torsion spring. The torsion spring is more conducive to the reset of the driving end1312.

In an embodiment of the present invention, the elastic member is one of a compression spring, a tension spring, and a torsion spring. Preferably, as shown inFIG.10a, in this embodiment of the present invention, the elastic member is a torsion spring, one end of the driving wheel cover201is provided with a cylindrical part202for sleeving the torsion spring203, one end of the torsion spring203is abutted against the driving tube204, and the other end is inserted on the driving wheel cover201. In other embodiments of the present invention, the other end of the torsion spring203can also abut against the driving tube204, or abut against the side surface (non-gear surface) of the driving wheel200. By pressing the driving tube204or side surface of the driving wheel200, the maximum static friction force on the driving wheel200can be increased, thereby preventing the driving wheel200from reversing. The specific abutting position and direction can be adjusted according to the required friction force range. The torsion spring203can provide elastic force with larger range, so it can better elastically fix the driving wheel and prevent the driving wheel from reversing.

In another embodiment of the present invention, at least one elastic rod is provided on the driving wheel cover201. As shown inFIG.10bandFIG.10d, the driving wheel cover201is provided with a U-shaped elastic rod205. The “-”-shaped part spans the top of the driving wheel cover201, one end of the U-shaped elastic rod205abuts against the A position of the driving tube204, and the abutting position on the other side is not shown in the figure. It should be noted that, in the embodiment of the present invention, both ends of the U-shaped elastic rod205may fully or partially abut against the side surface of the driving wheel tube204or the driving wheel200. An L-shaped elastic rod206is also provided on the driving wheel cover201. Referring to the directions shown inFIG.10bandFIG.10d, the “-”-shaped part of the L-shaped elastic rod206straddles the top of the driving wheel cover201,” The “I” part abuts against the B position of the driving wheel tube204, and the “I” part may also abut against the side surface of the driving wheel200. The U-shaped elastic rod205and/or the L-shaped elastic rod206can increase the maximum static friction force on the driving wheel200by pressing the driving tube204or the side surface of the driving wheel200, thereby preventing the driving wheel200from reversing. Preferably, a groove209is also provided at the top of the driving wheel cover201, and the U-shaped elastic rod205and the L-shaped elastic rod206are engaged on the driving wheel cover201through the groove209, so that the U-shaped elastic rod205and/or the L-shaped elastic rod206can be engaged on the driving wheel cover201more stably to provide a more stable elastic friction force range to prevent the driving wheel200from reversing, and at the same time, the driving wheel200can be elastically fixed. It should be noted that, in the embodiment of the present invention, the specific shape of the elastic rod is not specifically limited, and can be flexibly arranged according to the design features of the driving wheel cover201, the number of elastic rods, and the abutting position of the elastic rod abutted on the driving wheel assembly is also not particularly limited, and can be adjusted according to the required frictional force range.

In yet another embodiment of the present invention, the elastic member is one or more of silicone, rubber, latex, and spring steel. Preferably, as shown inFIG.10c, in this embodiment of the present invention, the elastic member is silicone, at least a silica gel207is disposed on the cover engaging portion208and abuts against the driving tube204. The silica gel207exerts pressure on the driving tube204to increase the maximum static friction force received by the driving wheel200and prevent the driving wheel200from reversing. The silica gel207and the cover engaging portion208are integrated formed, and are symmetrically abutted on both sides of the drive tube204to provide a stable elastic friction force range to prevent the drive wheel200from reversing, and at the same time, the driving wheel200can be elastically fixed to further reduce the quantity of the components and the volume of the infusion device.

It should be noted that, in the above-mentioned embodiments of the invention, for the elastic members, such as the torsion spring203, the U-shaped elastic rod205, the L-shaped elastic rod206and the silicone207, arranged on the driving wheel cover201, the types, quantities, positions, layout such as the abutting position on the driving tube204or the driving wheel200, are not specifically limited here, and can be selected according to actual needs. For example, the torsion spring203and the silicone207can be selected to provide elastic friction at the same time, as shown inFIG.10a, as long as the elastic friction force can be provided to prevent the driving wheel200from reversing, and the driving wheel200can be elastically fixed at the same time.

In yet another embodiment of the present invention, the elastic member and the reset unit1320are the same member. Preferably, the reset unit1320is a torsion spring, one end is connected to the driving unit1310, and the other end is abutted against the driving tube204or side surface of the driving wheel200. By applying pressure to the driving tube204or the side surface of the driving wheel200, the maximum static friction force on the driving wheel200can be increased, thereby preventing the driving wheel200from reversing. The location of the reset unit1320on the driving wheel cover200is not specifically limited here, and may be provided on the top, side or other positions of the driving wheel cover200. Therefore, in the embodiment of the present invention, the reset unit1320can not only provide elastic force to make the driving end1312perform the reset movement, but also can provide elastic friction force to prevent the driving wheel from reversing, and at the same time, it can assist the driving wheel cover200to elastically fix the driving wheel200, further reducing the number of parts and reducing the volume of the infusion device.

As a summary, the present invention discloses a drug infusion device with elastic anti-reverse member, at least one elastic member is provided on the driving wheel cover of the infusion device, abutting against the driving wheel assembly, and by applying pressure to the driving wheel assembly, the static friction force on the driving wheel can be increased to prevent the driving wheel from reversing. The type, quantity, location and layout of the elastic members can be flexibly arranged on the driving wheel cover, making full use of the internal space and effectively reducing the volume of the infusion device. The elastic members provide variable elastic friction within a certain range, which can better prevent the driving wheel from reversing. The elastic member is arranged on the driving wheel cover, no other components are needed to carry it, making full use of the internal space of the infusion device, increasing the compactness of the internal design, and the elastic member can also assist the driving wheel cover elastically fix the driving wheel, which greatly enhances the user experience.

While the invention has been described in detail regarding the specific embodiments of the present invention, it should be understood that it will be appreciated by those skilled in the art that the above embodiments may be modified without departing from the scope and spirit of the invention. The appended claims define the scope of the invention.