Injection device

Abstract

The present application relates to an injection device. It includes: a shell, having a cavity with two ends open, including a distal end connected to an injection container and a proximal end opposite thereto; a push rod, located in the cavity, used to push the piston in the container to move, one end connected to the piston of the container, and the other end extending in a direction away from the container; a push handle, located at the proximal end of the shell, the push handle having the freedom to rotate around the axis of the push rod and move axially along the push rod; a force transmission sleeve, located in the cavity, used to transmit the external force received by the push handle to the push rod; the force transmission sleeve is circumferentially connected to the push handle to rotate with the rotation of the push handle, and the force transmission sleeve is axially abutted against the push handle to move axially with the axial movement of the push handle; the force transmission sleeve is provided with a threaded hole, and the outer circumference of the push rod is provided with an external thread matching the threaded hole. The technical solution of the present application can solve the technical problems of complex structure and high cost.

Description

Technical Field

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

[0002] The syringe is a common medical device. As early as the 15th century, people had learned the principle of the syringe. It mainly uses a needle to extract or inject gas or liquid. The syringe can also be used for medical equipment and containers, such as some scientific instruments in chromatography that inject through a rubber diaphragm. The syringe consists of a syringe with a small hole at the front end and a matching piston core rod. It is used to inject a small amount of liquid or other substances into or extract from areas that are inaccessible by other methods. When the piston core rod is pulled out, the liquid or gas is sucked from the small hole at the front end of the syringe, and when the piston core rod is pushed in, the liquid or gas is squeezed out.

[0003] For diabetic patients, artificial insulin needs to be injected subcutaneously. In order to prevent artificial insulin from being contaminated, artificial insulin is placed in a special medicine bottle with a piston at one end of the medicine bottle. During injection, the piston at one end of the medicine bottle is pushed by the syringe to squeeze the liquid medicine out from the other end and enter the human body through the needle. Since different diabetic patients need different injection doses, the syringe needs to be provided with a structure that accurately limits the dose. In the prior art, the syringe with an accurate dose limit has the technical problems of complex structure and high manufacturing cost. Summary of the invention

[0004] In view of this, an embodiment of the present application provides an injection device to solve at least one problem existing in the background technology.

[0005] To achieve the above purpose, the technical solution of this application is implemented as follows:

[0006] The present application provides an injection device, comprising:

[0007] A housing having a cavity with two ends opened, including a distal end connected to a container for injection and an opposite proximal end;

[0008] A push rod, located in the cavity, used to push the piston in the container to move, one end of which is connected to the piston of the container, and the other end of which extends in a direction away from the container;

[0009] A push handle, located at the proximal end of the housing, is used to receive external force, and the push handle has the freedom to rotate around the axis of the push rod and move along the axial direction of the push rod; the rotation of the push handle is the movement required for the injection device to achieve dose adjustment, and the axial movement of the push handle is the movement required for the injection device to achieve injection;

[0010] A force transmission sleeve is located in the cavity and is used to transmit the external force received by the push handle to the push rod; the force transmission sleeve is circumferentially connected to the push handle so as to rotate along with the rotation of the push handle, and the force transmission sleeve is axially abutted against the push handle so as to move axially along with the axial movement of the push handle;

[0011] The force transmission sleeve is provided with a threaded hole, and the outer circumference of the push rod is provided with an external thread matching the threaded hole, so as to achieve: when the force transmission sleeve rotates, the force transmission sleeve spirally rises or spirally descends, and the push rod is fixed; when the force transmission sleeve moves axially, the push rod moves axially following the axial movement of the force transmission sleeve.

[0012] Optionally, the injection device further comprises:

[0013] A connecting middle piece, the first end of which is circumferentially connected to the push handle, and the second end of which is circumferentially connected to the force transmission sleeve, and the force transmission sleeve establishes a circumferential connection with the push handle through the connecting middle piece; and the first end of the connecting middle piece is axially abutted with the push handle, and the second end is axially abutted with the force transmission sleeve, and the force transmission sleeve establishes an axial abutment with the push handle through the connecting middle piece.

[0014] Optionally, a first blind hole extending along the axial direction of the push rod is formed at one end of the push handle facing the push rod, and the first end of the connecting middle piece has a first protrusion extending into the first blind hole and adapted to the size of the first blind hole, so as to axially align the connecting middle piece with the push handle to achieve axial abutment between the connecting middle piece and the push handle.

[0015] Optionally, a first blind hole extending along the axial direction of the push rod is formed at one end of the push handle facing the push rod, and the first end of the connecting middle piece has a first protrusion extending into the first blind hole, and the radial length of the first protrusion is greater than or equal to the radial length of the first blind hole, so that the connecting middle piece and the push handle are circumferentially connected by friction force.

[0016] Optionally, the pushing handle comprises:

[0017] A first blind hole is formed at one end of the push handle facing the push rod and extends along the axial direction of the push rod; the first blind hole has at least two apertures, a first aperture and a second aperture, which are staggered in the circumferential direction;

[0018] The first elastic member is located in the first blind hole, and the direction of the elastic force is the same as the axial direction of the push rod. The first end of the connecting middle member has a first protrusion extending into the first blind hole, and the radial size of the first protrusion is larger than the first aperture and smaller than the second aperture. Under the elastic force of the first elastic member, the first protrusion is clamped in the first aperture to circumferentially connect the connecting middle member to the push handle.

[0019] Optionally, the first blind hole is an annular hole surrounding the push rod, and the first end of the connecting middle piece is also configured to be annular to correspond to the first blind hole; the first protrusion protrudes from the side wall of the first end of the connecting middle piece.

[0020] Optionally, a second blind hole extending along the axial direction of the push rod is formed at one end of the force transmission sleeve connected to the connecting middle piece, and the second end of the connecting middle piece can extend into the second blind hole to axially align the connecting middle piece with the force transmission sleeve to achieve axial abutment between the connecting middle piece and the force transmission sleeve.

[0021] Optionally, a second blind hole extending along the axial direction of the push rod is formed at one end of the force transmission sleeve connected to the connecting middle piece, and the second end of the connecting middle piece can extend into the second blind hole, and the second end of the connecting middle piece is provided with at least one second protrusion abutting against the inner wall of the second blind hole, so as to realize circumferential connection between the connecting middle piece and the force transmission sleeve through friction force.

[0022] Optionally, the second end of the connecting middle piece includes a slope section, and two ends of the slope section are respectively abutted against two opposite inner walls of the second blind hole.

[0023] Optionally, at least one end of the slope section is provided with a plane parallel to the inner wall of the second blind hole to increase the contact area with the inner wall.

[0024] Optionally, the injection device further comprises:

[0025] The second elastic member is arranged along the radial direction of the push rod and is located between the connecting middle member and the force transmission sleeve so that the connecting middle member and the force transmission sleeve are in close contact with each other in the radial direction of the push rod.

[0026] Optionally, the injection device further comprises:

[0027] A scale ring is sleeved on the force transmission sleeve and is sleeved by the housing; the force transmission sleeve and the scale ring are clearance-matched so that the force transmission sleeve can perform spiral upward or spiral downward motion relative to the scale ring;

[0028] The outer wall of the scale ring is provided with scales corresponding to the injection dose, and the outer wall of the shell is provided with a window capable of displaying the scales; the push handle or the force transmission sleeve is provided with a preset structure capable of driving the scale ring to move axially, so that when the push handle moves axially, the scale ring is driven to move axially, and the injection dose is indicated by the scales;

[0029] The scale ring is loosely matched with the housing so that the scale ring can move axially relative to the housing.

[0030] Optionally, the inner wall of the scale ring is provided with a plurality of grooves extending in the axial direction and / or the circumferential direction so as to reduce the friction force when the force transmission sleeve can spirally rise or spirally descend relative to the scale ring.

[0031] Optionally, the preset structure includes a third protrusion arranged on the outer wall of the pushing handle, and a fourth protrusion on the inner wall of the scale ring that cooperates with the third protrusion.

[0032] Optionally, the injection device further comprises:

[0033] The third elastic member is located between the push rod and the push handle. The push handle has an end facing the push rod and is provided with a receiving cavity for accommodating the third elastic member so as to move away from the push rod under the elastic force of the third elastic member until the third protrusion abuts against the fourth protrusion.

[0034] The injection device provided by the embodiment of the present application comprises: a shell having a cavity with two ends opened, including a distal end connected to an injection container and an opposite proximal end; a push rod located in the cavity and used to push a piston in the container to move, one end of which is connected to the piston of the container and the other end of which extends in a direction away from the container; a push handle located at the proximal end of the shell and used to receive external force, the push handle having the freedom to rotate around the axis of the push rod and to move along the axial direction of the push rod; the rotation of the push handle is the movement required for the injection device to achieve dosage adjustment, and the axial movement of the push handle is the movement required for the injection device to achieve injection; The force transmission sleeve is located in the cavity and is used to transmit the external force received by the push handle to the push rod; the force transmission sleeve is circumferentially connected to the push handle to rotate with the rotation of the push handle, and the force transmission sleeve is axially abutted with the push handle to move axially with the axial movement of the push handle; the force transmission sleeve is provided with a threaded hole, and the outer circumference of the push rod is provided with an external thread matching the threaded hole, so as to achieve: when the force transmission sleeve rotates, the force transmission sleeve spirally rises or spirally descends, and the push rod is fixed; when the force transmission sleeve moves axially, the push rod moves axially following the axial movement of the force transmission sleeve. It can be seen that the injection device of the embodiment of the present application establishes a circumferential connection and an axial abutment relationship between the push handle and the force transmission sleeve, and sets the force transmission sleeve and the push rod to be threadedly connected; in this way, only by the rotation or axial movement of the push handle, the dosage adjustment and injection processes of the injection device can be completed through the cooperation of the force transmission sleeve and the push rod, which simplifies the structure, reduces the number of parts, and reduces the cost. Therefore, the injection device of the embodiment of the present application can solve the technical problems of complex structure and high cost.

[0035] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0037] Figure 1 A schematic diagram of an injection device provided in an embodiment of the present application;

[0038] Figure 2 for Figure 1 A cross-sectional view of

[0039] Figure 3 for Figure 2 Schematic diagram after disassembling the medicine bottle;

[0040] Figure 4 for Figure 3 A local enlarged schematic diagram of the middle A;

[0041] Figure 5 A schematic diagram of a push handle in an injection device provided in an embodiment of the present application;

[0042] Figure 6 A schematic diagram of a connecting intermediate piece in an injection device provided in an embodiment of the present application;

[0043] Figure 7 A schematic diagram (cross-sectional view) of a force transmission sleeve in an injection device provided in an embodiment of the present application;

[0044] Figure 8 for Figure 3 A partial enlarged view of point B in the middle;

[0045] Fig. 9 A schematic diagram of a housing in an injection device provided in an embodiment of the present application.

[0046] Description of reference numerals:

[0047] 10. Shell; 12. Window; 20. Push rod; 22. External thread; 30. Push handle; 32. First blind hole; 34. First elastic member; 36. Third protrusion; 40. Force transmission sleeve; 42. Threaded hole; 44. Second blind hole; 52. Medicine bottle; 521. Piston; 54. Medicine chamber; 60. Scale ring; 62. Fourth protrusion; 70. Connecting middle member; 72. First protrusion; 74. Second protrusion; 82. Second elastic member; 84. Third elastic member. DETAILED DESCRIPTION

[0048] In order to make the technical solutions and beneficial effects of the present application more obvious and easy to understand, the following is a detailed description by listing specific embodiments. The drawings are not necessarily drawn to scale, and local features may be enlarged or reduced to more clearly show the details of the local features; unless otherwise defined, the technical and scientific terms used herein have the same meanings as those in the technical field to which the present application belongs.

[0049] In the description of the present application, terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "height", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicating orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of simplified description of the present application, and do not indicate that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and should not be understood as a limitation on the present application.

[0050] In this application, the terms "first" and "second" are used only for the purpose of clear description and should not be understood as the relative importance of the indicated features or the number of the indicated technical features. Therefore, the features defined as "first" and "second" can explicitly include at least one of the features. In the description of this application, "multiple" means at least two, such as two, three, etc.; "several" means at least one, such as one, two, three, etc., unless otherwise clearly and specifically defined.

[0051] In this application, unless otherwise clearly defined, the terms "install", "connect", "connect", "fix", "set", etc. should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0052] In the present application, unless otherwise clearly defined, a first feature being “on”, “above”, “above”, “below”, “below”, “below” or “below” a second feature may mean that the first feature is in direct contact with the second feature, or the first feature and the second feature are in indirect contact with each other through an intermediate medium. Moreover, a first feature being “on”, “above” or “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the horizontal height of the first feature is higher than the horizontal height of the second feature. A first feature being “below”, “below” or “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the horizontal height of the first feature is lower than the horizontal height of the second feature.

[0053] In order to thoroughly understand the present application, detailed steps and detailed structures will be presented in the following description to illustrate the technical solution of the present application. The preferred embodiments of the present application are described in detail below, but in addition to these detailed descriptions, the present application may also have other implementation methods.

[0054] In view of the technical problems in the related art, the present application provides an injection device. Figure 1-Figure 3 , the injection device comprises:

[0055] The housing 10 has a cavity with two ends open, including a distal end connected to the injection container and an opposite proximal end;

[0056] A push rod 20, located in the cavity, used to push the piston 521 in the container to move, one end of which is connected to the piston 521 of the container, and the other end of which extends in a direction away from the container;

[0057] The push handle 30 is located at the proximal end of the housing 10 and is used to receive external force. The push handle 30 has the freedom to rotate around the axis of the push rod 20 and move along the axial direction of the push rod 20. The rotation of the push handle 30 is the movement required for the injection device to adjust the dosage, and the axial movement of the push handle 30 is the movement required for the injection device to achieve injection.

[0058] The force transmission sleeve 40 is located in the cavity and is used to transmit the external force received by the push handle 30 to the push rod 20; the force transmission sleeve 40 is circumferentially connected to the push handle 30 so as to rotate following the rotation of the push handle 30, and the force transmission sleeve 40 is axially abutted against the push handle 30 so as to move axially following the axial movement of the push handle 30; the force transmission sleeve 40 is provided with a threaded hole 42, and the outer circumference of the push rod 20 is provided with an external thread 22 matching the threaded hole 42, so as to achieve: when the force transmission sleeve 40 rotates, the force transmission sleeve 40 spirally rises or spirally descends, and the push rod 20 is fixed; when the force transmission sleeve 40 moves axially, the push rod 20 moves axially following the axial movement of the force transmission sleeve 40.

[0059] For ease of introduction, Figure 2 The directions shown, such as up, down, left, right, etc., describe the positions and movements of various components.

[0060] The push rod 20 is generally provided with sufficient length, one end of which is used to connect to the piston 521 in the container, and the other end of which extends to the proximal end close to the housing 10. Corresponding to the housing 10, the push rod 20 may also include a distal end and a proximal end.

[0061] Here, the injection container can be a medicine bottle 52, that is, a bottle containing liquid medicine. It can be understood that it can also be a bottle containing other substances. The medicine bottle 52 can be fixed in the injection device through the medicine chamber 54, and the end of the medicine bottle 52 facing the injection device is provided with a piston 521 connected to the push rod 20, and the other end can be connected to the needle. Figure 2 In the figure, the medicine bottle 52 and the medicine chamber 54 are located in the lower half of the injection device, and the needle is at the bottom, which is not shown in the figure.

[0062] It can be understood that the circumferential connection can realize linkage in the circumferential direction, that is, when the push handle 30 rotates, the force transmission sleeve 40 rotates accordingly.

[0063] It can be understood that axial abutment can achieve axial linkage. Figure 2 In the embodiment, axial abutment refers to upper and lower abutment.

[0064] According to the circumferential and axial linkage established between the force transmission sleeve 40 and the push handle 30, and the threaded connection between the force transmission sleeve 40 and the push rod 20, it can be deduced that: when the push handle 30 rotates, the force transmission sleeve 40 can be spirally ascended or descended, so that the injection dose can be adjusted by adjusting the axial position of the force transmission sleeve 40; when the push handle 30 moves axially, that is, moves in a direction close to the force transmission sleeve 40, the force transmission sleeve 40 also moves in the same direction, which can push the push rod 20 downward for injection.

[0065] Specifically, the thread of the push rod 20 may be right-handed, so the push handle 30 rotates counterclockwise and the force transmission sleeve 40 spirally rises to adjust the dosage.

[0066] In order to make it easier to understand the embodiments of the present application, the working principle of the embodiments of the present application is introduced below. Figure 2 The embodiment of the present application mainly includes four processes: installing the medicine bottle 52, adjusting the dosage, injecting and resetting, which are as follows:

[0067] 1) Install the medicine bottle 52. The medicine bottle 52 and the medicine chamber 54 can be separate, that is, the medicine bottle 52 is loaded into the medicine chamber 54, and the medicine chamber 54 is loaded into the device. After the injection, the medicine bottle 52 is discarded, and the medicine chamber 54 can be reused repeatedly; the medicine bottle 52 and the medicine chamber 54 can also be integrated, and the medicine chamber 54 can be used after it is installed. After the injection, the medicine chamber 54 and the medicine bottle 52 are discarded together, and the medicine chamber 54 is disposable.

[0068] 2) Adjust the dose. Before the dose is adjusted, the lower end of the force transmission sleeve 40 abuts against the shell 10, that is, the force transmission sleeve 40 cannot move downward in the axial direction. Because the push rod 20 and the force transmission sleeve 40 are axially linked, the push rod 20 cannot move downward in the axial direction, that is, injection cannot be performed when the dose is not adjusted. Correspondingly, the scale displayed on the window 12 of the shell 10 by the scale ring 60 is "0". After the push handle 30 rotates counterclockwise, the force transmission sleeve 40 spirally rises relative to the push rod 20, and the lower end of the force transmission sleeve 40 is axially disengaged from the abutment with the shell 10, and the axial distance increases. Since the force transmission sleeve 40 and the push rod 20 move axially synchronously during injection, the increased axial distance determines the distance that the push rod 20 moves downward subsequently, and thus determines the dose of injection.

[0069] Furthermore, after the push handle 30 rotates counterclockwise, it drives the force transmission sleeve 40 to spirally rise. The spiral rise of the force transmission sleeve 40 also drives the push handle 30 to spirally rise, and the push handle 30 can drive the scale ring 60 to rise through the third protrusion 36 and the fourth protrusion 62, so that the scale displayed on the window 12 changes accordingly. Through corresponding calculations, the scale displayed on the window 12 can correspond to the injected dose, and the function of adjusting the dose can be realized.

[0070] It is understandable that the lower end of the force transmission sleeve 40 abuts against the housing 10 directly or indirectly through other components. That is, any structure that makes the force transmission sleeve 40 unable to move downward is possible, which is well known to those skilled in the art and will not be described in detail.

[0071] 3) Injection. Press the push handle 30. Since the push handle 30 and the force transmission sleeve 40 are axially linked, the force transmission sleeve 40 moves axially downward, driving the push rod 20 to move downward, and injection is performed. At the same time, the push handle 30 axially squeezes the fourth protrusion 62 through the brim, driving the scale ring 60 to descend axially, and the scale gradually decreases until it returns to "0".

[0072] Note: In order to ensure that most medicine bottles 52 on the market can be fully injected, the push rod 20 needs to be designed to be long enough.

[0073] 4) Reset. After the medicine in the medicine bottle 52 is injected, the medicine chamber 54 is removed from the housing 10. A torque is applied from the lower end of the push rod 20 to make the push rod 20 spiral upward until the push rod 20 returns to the initial position.

[0074] Note: If the medicine in the medicine bottle 52 has not been completely injected, the medicine chamber 54 cannot be disassembled and the axial position of the push rod 20 cannot be retracted, otherwise the accuracy of the dosage will be affected.

[0075] The injection device of the embodiment of the present application establishes a circumferential connection and axial abutment relationship between the push handle 30 and the force transmission sleeve 40, and sets the force transmission sleeve 40 and the push rod 20 to be threadedly connected; thus, only by rotating or axially moving the push handle 30, the two processes of dose adjustment and injection of the injection device can be completed through the cooperation of the force transmission sleeve 40 and the push rod 20, which simplifies the structure, reduces the number of parts, and reduces the cost. Therefore, the injection device of the embodiment of the present application can solve the technical problems of complex structure and high cost.

[0076] The embodiments of the present application are mainly used for injecting liquid medicines into diabetic patients or other patients, but those skilled in the art will understand that it can also be used for injecting or pushing other fluid products, which will not be described in detail here.

[0077] In other embodiments of the present application, reference Figure 3 , the injection device also includes:

[0078] The connecting middle piece 70 has a first end circumferentially connected to the push handle 30, and a second end circumferentially connected to the force transmission sleeve 40, and the force transmission sleeve 40 establishes a circumferential connection with the push handle 30 through the connecting middle piece 70; and the first end of the connecting middle piece 70 is axially abutted against the push handle 30, and the second end is axially abutted against the force transmission sleeve 40, and the force transmission sleeve 40 establishes an axial abutment with the push handle 30 through the connecting middle piece 70.

[0079] This helps to simplify the structure of the push handle 30 or the force transmission sleeve 40 and reduce the manufacturing cost. Figure 2 In the embodiment, the first end is the upper end and the second end is the lower end.

[0080] In other embodiments of the present application, reference Figure 3 and Figure 4 A first blind hole 32 extending along the axial direction of the push rod 20 is formed at one end of the push handle 30 facing the push rod 20, and a first protrusion 72 extending into the first blind hole 32 and matching the size of the first blind hole 32 is provided at the first end of the connecting middle piece 70, so that the connecting middle piece 70 is axially aligned with the push handle 30 to achieve axial abutment between the connecting middle piece 70 and the push handle 30.

[0081] The first blind hole 32 can be used to align the connecting intermediate piece 70 with the pushing handle 30 in the axial direction. Furthermore, when the pushing handle 30 is subjected to axial force, it will not slip in the radial direction, and the force application direction is more accurate.

[0082] In other embodiments of the present application, reference Figure 3 and Figure 4 A first blind hole 32 extending along the axial direction of the push rod 20 is formed at one end of the push handle 30 facing the push rod 20, and a first end of the connecting middle piece 70 has a first protrusion 72 extending into the first blind hole 32, and a radial length of the first protrusion 72 is greater than or equal to a radial length of the first blind hole 32, so that the connecting middle piece 70 and the push handle 30 are circumferentially connected by friction.

[0083] In this way, the first end of the connecting intermediate member 70 is not easy to slip out after being inserted into the first blind hole 32. The first protrusion 72 can also be used to clamp the opening of the first blind hole 32 to achieve the purpose of circumferential connection between the first end of the connecting intermediate member 70 and the pushing handle 30.

[0084] As for how to assemble, force can be applied to elastically deform the first protrusion 72 and force it to extend inward.

[0085] In other embodiments of the present application, reference Figure 3 and Figure 4 , the pushing handle 30 comprises:

[0086] A first blind hole 32 is formed at one end of the push handle 30 facing the push rod 20 and extends along the axial direction of the push rod 20; the first blind hole 32 has at least two apertures, a first aperture and a second aperture, which are staggered in the circumferential direction;

[0087] The first elastic member 34 is located in the first blind hole 32, and the direction of the elastic force is the same as the axial direction of the push rod 20. The first end of the connecting middle member 70 has a first protrusion 72 extending into the first blind hole 32. The radial size of the first protrusion 72 is larger than the first aperture and smaller than the second aperture. Under the elastic force of the first elastic member 34, the first protrusion 72 is clamped in the first aperture to circumferentially connect the connecting middle member 70 to the push handle 30.

[0088] In this way, the first end of the connecting middle piece 70 can be extended into the first blind hole 32 from the second aperture, and then rotated and stuck at the first aperture through the first elastic piece 34, so as to achieve the purpose of circumferentially connecting the connecting middle piece 70 with the pushing handle 30.

[0089] Specifically, the first elastic member 34 may be a compression spring.

[0090] In other embodiments of the present application, reference Figure 5 The first blind hole 32 is an annular hole surrounding the push rod 20, and the first end of the connecting intermediate member 70 is also set to be annular to correspond to the first blind hole 32. Figure 6 ; The first protrusion 72 protrudes from the side wall of the first end of the connecting middle piece 70.

[0091] In this way, the contact area between the connecting intermediate piece 70 and the pushing handle 30 is larger, making the circumferential connection between the two more secure.

[0092] In other embodiments of the present application, reference Figure 3 and Figure 7 A second blind hole 44 extending along the axial direction of the push rod 20 is formed at one end of the force transmission sleeve 40 connected to the connecting middle piece 70, and the second end of the connecting middle piece 70 can extend into the second blind hole 44 to axially align the connecting middle piece 70 with the force transmission sleeve 40 to achieve axial abutment between the connecting middle piece 70 and the force transmission sleeve 40.

[0093] As with the first blind hole 32 , the second blind hole 44 can be used to align the axial direction of the connecting intermediate piece 70 with the force transmission sleeve 40 , and when the connecting intermediate piece 70 transmits force axially, it will not slip in the radial direction, and the force application direction is more accurate.

[0094] In other embodiments of the present application, reference Figure 3 and Figure 7A second blind hole 44 extending along the axial direction of the push rod 20 is formed at one end of the force transmission sleeve 40 connected to the connecting middle piece 70, and the second end of the connecting middle piece 70 can extend into the second blind hole 44, and the second end of the connecting middle piece 70 is provided with at least one second protrusion 74 abutting against the inner wall of the second blind hole 44, so as to realize the circumferential connection between the connecting middle piece 70 and the force transmission sleeve 40 through friction force.

[0095] A circumferential connection is established by the friction force generated by the abutment with the inner wall of the second blind hole 44, which has the characteristics of simple structure and fast assembly.

[0096] In other embodiments of the present application, reference Figure 3 and Figure 6 The second end of the connecting intermediate piece 70 includes a slope section, and the two ends of the slope section are respectively in contact with the two opposite inner walls of the second blind hole 44 .

[0097] It can be understood that both ends of the slope section are relatively inclined, that is, relatively protruding, including two second protruding portions 74 ( Figure 8 Therefore, the connecting intermediate member 70 can respectively contact with the two opposite inner walls of the second blind hole 44 by providing the slope section, thereby generating a greater friction force and making the circumferential connection more secure.

[0098] In other embodiments of the present application, reference Figure 8 At least one end of the slope section is provided with a plane parallel to the inner wall of the second blind hole 44 to increase the contact area with the inner wall.

[0099] Setting a plane can change the contact from line contact to surface contact, increase the contact area, and thus increase the friction.

[0100] Specifically, both ends of the slope section are provided with the planes, which can further increase the contact area.

[0101] In other embodiments of the present application, reference Figure 3 and Figure 8 , the injection device further comprises:

[0102] The second elastic member 82 is disposed along the radial direction of the push rod 20 and is located between the connecting middle member 70 and the force transmission sleeve 40 so that the connecting middle member 70 and the force transmission sleeve 40 are in close contact with each other in the radial direction of the push rod 20 .

[0103] That is, the second end of the connecting intermediate piece 70 extending into the second blind hole 44 can be made to abut against the inner wall of the second blind hole 44 more closely, which is beneficial to increase the friction force and further increase the firmness of the circumferential connection.

[0104] Specifically, the second elastic member 82 may be a tension spring.

[0105] In other embodiments of the present application, reference Figure 3 , the injection device further comprises:

[0106] The scale ring 60 is sleeved on the force transmission sleeve 40 and is sleeved by the housing 10; the force transmission sleeve 40 and the scale ring 60 are clearance-matched, so that the force transmission sleeve 40 can perform spiral ascending or spiral descending motion relative to the scale ring 60;

[0107] The outer wall of the scale ring 60 is provided with scales corresponding to the injection dose, and the outer wall of the housing 10 is provided with a window 12 for displaying the scales. Fig. 9 The push handle 30 or the force transmission sleeve is provided with a preset structure capable of driving the scale ring 60 to move axially, so as to drive the scale ring 60 to move axially when the push handle 30 moves axially, and indicate the injection dose through the scale; the scale ring 60 is clearance-matched with the housing 10, so that the scale ring 60 can move axially relative to the housing 10.

[0108] The adjusted dosage can be checked more conveniently through the scale ring 60. Moreover, the movement of the force transmission sleeve 40 and the push handle 30 can be supported through the scale ring 60, and the structural strength of the entire injection device is also strengthened.

[0109] In other embodiments of the present application, reference Figure 3 The inner wall of the scale ring 60 is provided with a plurality of grooves extending in the axial direction and / or the circumferential direction to reduce the friction force when the force transmission sleeve 40 can spirally rise or spirally descend relative to the scale ring 60 .

[0110] Specifically, since the movement of the force transmission sleeve 40 is spirally ascending or spirally descending, the groove may extend circumferentially.

[0111] More specifically, the groove may be a spiral groove, which is more in line with the movement mode of the force transmission sleeve 40. In addition, the spiral groove may be processed by processing an internal thread, and the internal thread is a standard part with low processing cost.

[0112] In other embodiments of the present application, reference Figure 3 and Figure 5 The preset structure includes a third protrusion 36 arranged on the outer wall of the pushing handle 30, and a fourth protrusion 62 on the inner wall of the scale ring 60 that cooperates with the third protrusion 36.

[0113] The third protrusion 36 and the fourth protrusion 62 can reduce the cost of processing and assembling.

[0114] In other embodiments of the present application, reference Figure 3 and Figure 5 , the injection device further comprises:

[0115] The third elastic member 84 is located between the push rod 20 and the push handle 30. The push handle 30 has an end facing the push rod 20 with a receiving cavity for accommodating the third elastic member 84 so as to move away from the push rod 20 under the elastic force of the third elastic member 84 until the third protrusion 36 abuts against the fourth protrusion 62.

[0116] That is, the axial connection relationship between the push handle 30 and the scale ring 60 is maintained by the elastic force of the third elastic member 84 , and the scale ring 60 can move axially synchronously with the push handle 30 during the process of adjusting the dosage.

[0117] Furthermore, during the injection process, the brim of the push handle 30 axially presses the fourth protrusion 62 to achieve the downward movement of the scale ring 60. In order to make the scale more accurate, the structure is designed as follows: before injection, the distance between the bottom end of the brim of the push handle 30 and the fourth protrusion 62 is the same as the distance between the first end of the connecting middle piece 70 and the top wall of the first blind hole 32. The distance between the bottom end of the brim of the push handle 30 and the fourth protrusion 62 is marked as G1 in the drawings (see Figure 3 ), the distance between the first end of the connecting intermediate member 70 and the top wall of the first blind hole 32 is marked as G2 in the drawings (see Figure 4 ).

[0118] It should be understood that the above embodiments are exemplary and are not intended to include all possible implementations included in the claims. Various modifications and changes may be made on the basis of the above embodiments without departing from the scope of the present disclosure. Similarly, the various technical features of the above embodiments may be arbitrarily combined to form other embodiments of the present application that may not be explicitly described. Therefore, the above embodiments only express several implementations of the present application and do not limit the scope of protection of the patent of this application.

Claims

1. An injection device, characterized in that: include: A housing having a cavity with two ends opened, including a distal end connected to a container for injection and an opposite proximal end; A push rod, located in the cavity, used to push the piston in the container to move, one end of which is connected to the piston of the container, and the other end of which extends in a direction away from the container; A push handle, located at the proximal end of the housing, is used to receive external force, and the push handle has the freedom to rotate around the axis of the push rod and move along the axial direction of the push rod; the rotation of the push handle is the movement required for the injection device to achieve dose adjustment, and the axial movement of the push handle is the movement required for the injection device to achieve injection; A force transmission sleeve is located in the cavity and is used to transmit the external force received by the push handle to the push rod; the force transmission sleeve is circumferentially connected to the push handle so as to rotate along with the rotation of the push handle, and the force transmission sleeve is axially abutted against the push handle so as to move axially along with the axial movement of the push handle; The force transmission sleeve is provided with a threaded hole, and the outer circumference of the push rod is provided with an external thread matching the threaded hole, so as to achieve: when the force transmission sleeve rotates, the force transmission sleeve spirally rises or spirally descends, and the push rod is fixed; when the force transmission sleeve moves axially, the push rod moves axially following the axial movement of the force transmission sleeve.

2. The injection device according to claim 1, characterized in that The injection device also includes: A connecting middle piece, the first end of which is circumferentially connected to the push handle, and the second end of which is circumferentially connected to the force transmission sleeve, and the force transmission sleeve establishes a circumferential connection with the push handle through the connecting middle piece; and the first end of the connecting middle piece is axially abutted with the push handle, and the second end is axially abutted with the force transmission sleeve, and the force transmission sleeve establishes an axial abutment with the push handle through the connecting middle piece.

3. The injection device according to claim 2, characterized in that A first blind hole extending along the axial direction of the push rod is formed at one end of the push handle facing the push rod, and a first end of the connecting middle piece has a first protrusion extending into the first blind hole and adapted to the size of the first blind hole, so that the connecting middle piece is axially aligned with the push handle to achieve axial abutment between the connecting middle piece and the push handle.

4. The injection device according to claim 2, characterized in that A first blind hole extending along the axial direction of the push rod is formed at one end of the push handle facing the push rod, and the first end of the connecting middle piece has a first protrusion extending into the first blind hole, and the radial length of the first protrusion is greater than or equal to the radial length of the first blind hole, so that the connecting middle piece and the push handle are circumferentially connected by friction force.

5. The injection device according to claim 2, characterized in that The push handle comprises: A first blind hole is formed at one end of the push handle facing the push rod and extends along the axial direction of the push rod; the first blind hole has at least two apertures, a first aperture and a second aperture, which are staggered in the circumferential direction; The first elastic member is located in the first blind hole, and the direction of the elastic force is the same as the axial direction of the push rod. The first end of the connecting middle member has a first protrusion extending into the first blind hole, and the radial size of the first protrusion is larger than the first aperture and smaller than the second aperture. Under the elastic force of the first elastic member, the first protrusion is clamped in the first aperture to circumferentially connect the connecting middle member to the push handle.

6. The injection device according to claim 5, characterized in that The first blind hole is an annular hole surrounding the push rod, and the first end of the connecting middle piece is also configured to be annular to correspond to the first blind hole; the first protrusion protrudes from the side wall of the first end of the connecting middle piece.

7. The injection device according to claim 2, characterized in that A second blind hole extending along the axial direction of the push rod is formed at one end of the force transmission sleeve connected to the connecting middle piece, and the second end of the connecting middle piece can extend into the second blind hole to axially align the connecting middle piece with the force transmission sleeve to achieve axial abutment between the connecting middle piece and the force transmission sleeve.

8. The injection device according to claim 2, characterized in that A second blind hole extending along the axial direction of the push rod is formed at one end of the force transmission sleeve connected to the connecting middle piece, and the second end of the connecting middle piece can extend into the second blind hole, and the second end of the connecting middle piece is provided with at least one second protrusion abutting against the inner wall of the second blind hole, so as to realize circumferential connection between the connecting middle piece and the force transmission sleeve through friction force.

9. The injection device according to claim 8, characterized in that The second end of the connecting middle piece includes a slope section, and two ends of the slope section are respectively in contact with two opposite inner walls of the second blind hole.

10. The injection device according to claim 9, characterized in that At least one end of the slope section is provided with a plane parallel to the inner wall of the second blind hole to increase the contact area with the inner wall.

11. The injection device according to claim 7, characterized in that The injection device further comprises: The second elastic member is arranged along the radial direction of the push rod and is located between the connecting middle member and the force transmission sleeve so that the connecting middle member and the force transmission sleeve are in close contact with each other in the radial direction of the push rod.

12. The injection device according to claim 1, characterized in that The injection device further comprises: A scale ring is sleeved on the force transmission sleeve and is sleeved by the housing; the force transmission sleeve and the scale ring are clearance-matched so that the force transmission sleeve can perform spiral upward or spiral downward motion relative to the scale ring; The outer wall of the scale ring is provided with scales corresponding to the injection dose, and the outer wall of the shell is provided with a window capable of displaying the scales; the push handle or the force transmission sleeve is provided with a preset structure capable of driving the scale ring to move axially, so that when the push handle moves axially, the scale ring is driven to move axially, and the injection dose is indicated by the scales; The scale ring is loosely matched with the housing so that the scale ring can move axially relative to the housing.

13. The injection device according to claim 12, characterized in that The inner wall of the scale ring is provided with a plurality of grooves extending in the axial direction and / or the circumferential direction so as to reduce the friction force when the force transmission sleeve can spirally rise or spirally descend relative to the scale ring.

14. The injection device according to claim 12, characterized in that The preset structure includes a third protrusion arranged on the outer wall of the pushing handle, and a fourth protrusion on the inner wall of the scale ring that cooperates with the third protrusion.

15. The injection device according to claim 14, characterized in that The injection device further comprises: The third elastic member is located between the push rod and the push handle. The push handle has an end facing the push rod and is provided with a receiving cavity for accommodating the third elastic member so as to move away from the push rod under the elastic force of the third elastic member until the third protrusion abuts against the fourth protrusion.

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