Dose-adjustable disposable injection pen

Abstract

The utility model relates to the technical field of injection pens, in particular to a dosage-adjustable disposable injection pen which comprises a shell, a first cover body, a dosage adjusting rod, a limiting sleeve, a double-sided gear, a limiting knob, a screw rod, an injection button, a button spring, a guide sleeve, a button clamping seat, a push piece, a threaded seat and a second cover body. According to the disposable injection pen capable of adjusting the dosage, the double-sided gear is matched with the button spring, so that a user does not feel stuck when using the injection pen, and the acting force is reduced when the injection pen is operated.

Description

Technical Field

[0001] The utility model relates to the technical field of injection pens, in particular to a disposable injection pen with adjustable dosage. Background Art

[0002] With the advancement of medical technology, various injection pens and syringes are being used more and more widely.

[0003] The existing patent CN201821608038.7 describes a disposable injection pen with dosage feedback. Due to the structural limitations of the dosage adjustment rod and the limiting sleeve, this invention has a large torque when adjusting the dosage, and there is an obvious jamming feeling during dosage adjustment, error correction, and injection. The pressure of pressing the injection button is high, which is inconvenient for users to use. Utility Model Content

[0004] The technical problem to be solved by the utility model is: in order to solve the technical problem in the prior art, the utility model provides a disposable injection pen with adjustable dosage.

[0005] The utility model solves the technical problem by adopting the following technical solution: a disposable injection pen with adjustable dose, comprising: a shell, the shell is formed in a rod shape, and a receiving cavity is defined inside the shell and penetrates along its axial direction; a first cover body, the first cover body is formed in a rod shape and one end of which is connected to one end of the shell, a first installation cavity is defined inside the first cover body and penetrates along its axial direction, and a first thread is provided on the inner wall surface of the first cover body; a dose adjustment rod, the dose adjustment rod is movably arranged in the first installation cavity along the axial direction of the first installation cavity and one end of the dose adjustment rod stops at one end of the shell, a second installation cavity is defined inside the dose adjustment rod and a first thread matching with the first thread is provided on the outer wall surface, and the second installation cavity extends away from the inner wall of one end of the shell toward its axis to form a first tooth shape; a limiting sleeve, the limiting sleeve is arranged along the second installation cavity The mounting cavity is axially movably arranged in the second mounting cavity, the limiting sleeve is provided with an annular limiting portion, a third mounting cavity is defined in the limiting sleeve, and a second thread matching the second thread groove is provided on the outer wall surface, and a second tooth shape is formed on one end of the annular limiting portion close to the outer shell; a double-sided gear, and the two ends of the double-sided gear are respectively meshed with the first tooth shape and the second tooth shape; a limiting knob, the limiting knob is movably sleeved on the limiting sleeve along the axial direction of the limiting sleeve; a screw rod, the screw rod is movably arranged in the third mounting cavity along the axial direction of the third mounting cavity and one end is connected to one end of the outer shell; an injection button, the injection button is arranged in the second mounting cavity and protrudes from the other end of the dose adjustment rod, and a pressing rod is provided at the center of the injection button; a button spring is arranged between the injection button and the limiting sleeve.

[0006] Furthermore, it also includes: a guide sleeve, which is formed in a rod shape, and a fourth installation cavity axially penetrating therein is defined in the guide sleeve, the guide sleeve is movably arranged in the third installation cavity along the axial direction of the third installation cavity, and the screw rod is movably arranged in the fourth installation cavity along the axial direction of the fourth installation cavity.

[0007] Furthermore, the cross-section of the fourth mounting cavity in the guide sleeve is non-circular to prevent the screw rod from rotating relative to the guide rod.

[0008] Furthermore, a first boss is provided at one end of the dose adjustment rod away from the first tooth shape, and the inner hole of the first boss is larger than the outer diameter of the port of the limiting sleeve, so as to facilitate controlling the shaking amplitude of the limiting sleeve near the injection needle end.

[0009] Furthermore, it also includes: a button holder, which is arranged in the third installation cavity and can be movably sleeved on the pressing rod.

[0010] Further, the thread pitch of the first thread is greater than the thread pitch of the second thread.

[0011] Furthermore, it also includes: a threaded seat, the threaded seat is formed as a cylinder, the threaded seat is arranged at one end of the shell and is sleeved on the screw rod, and the threaded seat is connected with a third tooth shape.

[0012] Furthermore, it also includes: an elastic arm, one end of which is hinged to the guide sleeve, and the other end of which is meshed with the fourth tooth of the threaded seat.

[0013] Furthermore, it also includes: a second cover body, the second cover body is formed as a rod body with one end open and a chamber defined inside, and the second cover body is detachably mounted on the shell.

[0014] Furthermore, the limiting knob is provided with a first notch, the dose adjustment rod is provided with a second limiting rib, and the second limiting rib cooperates with the first notch so that the limiting knob can move axially along the second limiting rib in the dose adjustment rod.

[0015] The beneficial effects of the utility model are:

[0016] When the adjustable dose disposable injection pen of the utility model is used, when it is necessary to set the dose, the dose adjustment rod is rotated clockwise, and the dose adjustment rod is screwed out along the direction of the thread. The limit sleeve is connected to the guide rod slot, and the tooth surface on the guide rod is meshed with the tooth surface of the thread seat. When adjusting the dose, the meshed tooth surface limits the limit sleeve to rotate in the same direction as the dose adjustment rod. At this time, the double-sided gear is meshed with the second tooth shape on the limit sleeve, and the double-sided gear is not meshed with the first tooth shape on the dose adjustment rod. Therefore, the double-sided gear and the limit sleeve move away from the injection end by a tooth shape height, but move back under the action of the button spring force (sound prompt when adjusting the dose). The limit knob is affected by the limit groove of the dose adjustment rod, and the limit knob is threadedly connected to the limit sleeve. The limit sleeve does not rotate in the same direction as the dose adjustment rod, so that the limit knob and the dose adjustment rod are screwed out along the limit sleeve thread, and the dose setting is completed at this time.

[0017] When injecting, press the injection button, which is pressed down by force, compressing the button spring, so that there is no space for the double-sided gear, the limit sleeve and the dose adjustment rod to move up and down, so the double-sided gear and the limit sleeve cannot move up and down. The external force drives the dose adjustment rod to rotate counterclockwise, and the button holder, the double-sided gear and the limit sleeve rotate synchronously with the dose adjustment rod. The rotation of the limit sleeve causes the guide sleeve to rotate synchronously, and the guide sleeve is restricted from axial movement, so the screw and the guide sleeve rotate synchronously, and the screw moves toward the injection needle end until the dose adjustment rod hits the limiter, and the set dose injection is completed.

[0018] When the dose is set incorrectly, the dose adjustment rod is rotated, and the double-sided gear meshes with the tooth surface of the dose adjustment rod, and rotates back to the starting position synchronously with the dose adjustment rod. The limit sleeve does not rotate and moves a tooth profile height away from the injection end relative to the double-sided gear, but moves back under the action of the button spring (the sound prompt of the dose correction adjustment is given). The limit knob rotates with the dose adjustment rod to correct the wrong dose.

[0019] Through the cooperation of double-sided gears and button springs, users can use the product without feeling any lag and the force applied during operation is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0021] Figure 1 It is a schematic diagram of the overall structure of the disposable injection pen with adjustable dosage in the utility model.

[0022] Figure 2 It is a cutaway schematic diagram showing the whole of the utility model.

[0023] Figure 3 It is a schematic diagram of the dosage adjustment rod in the present utility model.

[0024] Figure 4It is a schematic diagram showing another angle of the dosage adjustment rod in the present invention.

[0025] Figure 5 It is a schematic diagram of the limiting sleeve in the utility model.

[0026] Figure 6 It is a schematic diagram showing the cooperation between the first tooth shape, the second tooth shape and the double-sided gear in the utility model.

[0027] Figure 7 It is a schematic diagram of the limit knob in the utility model.

[0028] Figure 8 It is a schematic diagram of the first cover body in the utility model.

[0029] Fig. 9 It is a schematic diagram of the threaded seat in the utility model.

[0030] Fig.10 It is a schematic diagram showing the combination of the limit sleeve and the threaded seat in the utility model.

[0031] In the figure: 1, housing; 11, limiting hole; 12, limiting surface; 2, first cover; 21, first thread; 3, dose adjustment rod; 31, first thread groove; 32, first tooth shape; 33, first boss; 34, second limiting rib; 35, second limiting member; 4, limiting sleeve; 41, annular limiting portion; 42, second thread; 43, second tooth shape; 44, first limiting rib; 45, first limiting member; 46, second boss; 5, double-sided Gear; 6. Limit knob; 61. First notch; 62. Second threaded groove; 63. Limit end face; 7. Screw; 8. Injection button; 81. Button spring; 82. Button holder; 83. Press rod; 9. Guide sleeve; 91. Threaded seat; 911. Third tooth shape; 912. Limit tooth; 913. First through hole; 92. Second cover; 93. Positioning groove; 94. Second notch; 95. Elastic arm; 96. Push piece; 97. Lower shell. DETAILED DESCRIPTION

[0032] Now the utility model is further described in detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, which only illustrate the basic structure of the utility model in a schematic manner, and therefore only show the components related to the utility model.

[0033] In the description of the present utility model, it is necessary to understand that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, features defined as "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present utility model, unless otherwise specified, "multiple" means two or more. In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it 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 it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] The utility model discloses a disposable injection pen with adjustable dosage.

[0035] Reference Figure 1 and Figure 2 A disposable injection pen with adjustable dose includes a shell 1, a first cover body 2, a dose adjustment rod 3, a limit sleeve 4, a double-sided gear 5, a limit knob 6, a screw 7, an injection button 8, a button spring 81, a guide sleeve 9, a button holder 82, a push piece 96, a threaded seat 91 and a second cover body 92.

[0036] Specifically, the housing 1 is formed in a rod shape, and a receiving cavity is defined inside the housing 1 along its axial direction. The first cover 2 is formed in a rod shape, and one end is connected to one end of the housing 1, and a first installation cavity is defined inside the first cover 2 along its axial direction. The inner wall surface of the first cover 2 is provided with a first thread 21.

[0037] The dose adjustment rod 3 is movably arranged in the first installation cavity along the axial direction of the first installation cavity and one end of the dose adjustment rod 3 stops at one end of the shell 1. The inside of the dose adjustment rod 3 defines a second installation cavity and the outer wall surface is provided with a first thread groove 31 that matches the first thread 21. The inner wall of the second installation cavity away from the end of the shell 1 extends toward its axis to form a first tooth shape 32.

[0038] The limiting sleeve 4 is movably arranged in the second mounting cavity along the axial direction of the second mounting cavity, and an annular limiting portion 41 is provided on the limiting sleeve 4. A third mounting cavity is defined in the limiting sleeve 4 and a second thread 42 is provided on the outer wall surface. A second tooth shape 43 is formed on one end of the annular limiting portion 41 close to the outer shell 1.

[0039] A first boss 33 is provided at one end of the dose adjustment rod 3 away from the first tooth shape 32. The inner hole of the first boss 33 is slightly larger than the outer diameter of the end of the limiting sleeve 4, so as to control the shaking amplitude of the limiting sleeve 4 near the injection needle end.

[0040] The guide sleeve 9 is formed in a rod shape, and an axially penetrating fourth installation cavity is defined in the guide sleeve 9. The guide sleeve 9 is movably disposed in the third installation cavity along the axial direction of the third installation cavity.

[0041] The screw rod 7 is movably disposed in the third mounting cavity along the axial direction of the third mounting cavity and one end of the screw rod 7 is connected to one end of the housing 1. The screw rod 7 is movably disposed in the fourth mounting cavity along the axial direction of the fourth mounting cavity. First limiting ribs 44 are evenly distributed on the inner wall of the third mounting cavity, and positioning grooves 93 are provided on the outer wall of the guide sleeve 9. The first limiting ribs 44 cooperate with the positioning grooves 93 so that the limiting sleeve 4 can move relative to the guide sleeve 9.

[0042] Both ends of the double-sided gear 5 are meshed with the first tooth profile 32 and the second tooth profile 43 respectively.

[0043] The limit knob 6 is movably mounted on the limit sleeve 4 along the axial direction of the limit sleeve 4. The limit knob 6 is provided with a second thread groove 62 that cooperates with the second thread 42. When the limit knob 6 moves to one end of the limit sleeve 4, it limits the movement of the dose adjustment rod 3.

[0044] The limiting sleeve 4 is fixedly connected with a second boss 46, which is engaged with the second thread groove 62, and this is the initial position of the dose. The limiting sleeve 4 is also provided with a first limiting member 45, and one side end face of the first limiting member 45 abuts against the limiting end face 63 of the limiting knob 6. At this time, the adjustable remaining dose of the injection pen is 0, and the injection pen cannot be used any more. The limiting knob 6 is provided with a first notch 61, and the dose adjustment rod 3 is provided with a second limiting rib 34 along its own axial direction. The first notch 61 is engaged with the second limiting rib 34 on the inner wall of the dose adjustment rod 3, so that the limiting knob 6 can move axially along the second limiting rib 34 in the dose adjustment rod 3.

[0045] The guide sleeve 9 has a second notch 94 extending along its own axial direction. The cross section of the fourth mounting cavity in the guide sleeve 9 is non-circular to prevent the screw rod 7 from rotating relative to each other. In this embodiment, it is waist-shaped. The threaded seat 91 is provided with a third tooth shape 911. Two elastic arms 95 are connected to the side wall of the guide sleeve 9. One end of the elastic arm 95 is hinged to the guide sleeve 9, and the other end is engaged with the third tooth shape 911 on the threaded seat 91. The angles of the two sides of the third tooth shape 911 are different to limit the unidirectional rotation of the guide sleeve 9 relative to the threaded seat 91. The threaded seat 91 is fixedly connected to the housing 1. The housing 1 is provided with a limiting hole. The threaded seat 91 is provided with a limiting tooth 912. The housing 1 is provided with a limiting surface 12. The limiting surface 12 cooperates with the limiting tooth 912 to limit the guide sleeve 9 from moving along its own axial direction. The threaded seat 91 is provided with a first through hole 913 with an internal thread. The first through hole 913 is connected with the external thread of the screw rod 7. The housing 1 is provided with a limiting hole 11 , which facilitates viewing of the dosage indication on the dosage adjustment rod 3 .

[0046] The injection button 8 is disposed in the second mounting cavity and protrudes from the other end of the dose adjustment rod 3 , and the center of the injection button 8 presses the rod 83 .

[0047] The limit knob 6 has multiple movable gears in the limit sleeve 4, each gear of the limit knob 6 corresponds to each unit of the drug amount in the shell 1, and the total number of gears of the limit knob 6 in the limit sleeve 4 is equal to the total number of units of the drug amount in the shell 1.

[0048] The button holder 82 is arranged in the third installation cavity and is movably sleeved on the pressing rod 83. The button spring 81 is arranged between the button holder 82 and the limiting sleeve 4, and one end of the button spring 81 abuts against.

[0049] It should be noted that the thread pitch of the first thread 21 is greater than the thread pitch of the second thread 42 for ease of adjustment.

[0050] The second cover 92 is formed as a rod with one end open and a chamber defined inside. The second cover 92 is detachably mounted on the housing 1. The second cover 92 is used to be threadedly connected to the injection needle and is convenient for accommodating a medicine bottle inside. One end of the push piece 96 is connected to the lead screw and the other end is inserted into the second cover 92.

[0051] Working principle: When in use, when it is necessary to set the dose, rotate the dose adjustment rod 3 clockwise, and the dose adjustment rod 3 is screwed out along the threaded direction. The limit sleeve 4 is connected to the guide rod slot, and the tooth surface on the guide rod is meshed with the tooth surface of the threaded seat 91. When adjusting the dose, the meshed tooth surface limits the limit sleeve 4 to rotate in the same direction as the dose adjustment rod 3. At this time, the double-sided gear 5 is meshed with the second tooth profile 43 on the limit sleeve 4, and the double-sided gear 5 is not meshed with the first tooth profile 32 on the dose adjustment rod 3. Therefore, the double-sided gear 5 and the limit sleeve 4 move away from the injection end by a tooth profile height, but move back under the action of the button spring 81 force (the sound prompt is emitted when adjusting the dose). The limit knob 6 is affected by the limit groove of the dose adjustment rod 3, and the limit knob 6 is threadedly connected to the limit sleeve 4. The limit sleeve 4 does not rotate in the same direction as the dose adjustment rod 3, so that the limit knob 6 and the dose adjustment rod 3 are screwed out along the limit sleeve 4 thread, and the dose setting is completed at this time.

[0052] During injection, the injection button 8 is pressed down by force, so that the button spring 81 is compressed, so that there is no space for the double-sided gear 5, the limiting sleeve 4 and the dose adjustment rod 3 to move up and down, so the double-sided gear 5 and the limiting sleeve 4 cannot move up and down. The external force drives the dose adjustment rod 3 to rotate counterclockwise, and the button holder 82, the double-sided gear 5 and the limiting sleeve 4 rotate synchronously with the dose adjustment rod 3. The rotation of the limiting sleeve 4 causes the guide sleeve 9 to rotate synchronously, and the guide sleeve 9 is restricted from axial movement, so the screw and the guide sleeve 9 rotate synchronously, and the screw moves toward the injection needle end until the dose adjustment rod 3 abuts against the limiting member, and the set dose injection is completed.

[0053] When the dose is set incorrectly, the dose adjustment rod 3 is rotated, the double-sided gear 5 meshes with the tooth surface of the dose adjustment rod 3, and rotates back to the starting position synchronously with the dose adjustment rod 3. The limit sleeve 4 does not rotate and moves a tooth profile height away from the injection end relative to the double-sided gear 5, but moves back under the action of the button spring 81 (the sound prompt of the dose error correction adjustment is emitted). The limit knob 6 rotates with the dose adjustment rod 3 to achieve the correction of the wrong dose.

[0054] Based on the above ideal embodiments of the utility model, the relevant staff can make various changes and modifications without deviating from the technical concept of the utility model through the above description. The technical scope of the utility model is not limited to the content of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A disposable injection pen with adjustable dosage, characterized in that: include: A housing (1), the housing (1) being formed in a rod shape, and defining an accommodating cavity extending through the housing (1) in its axial direction; A first cover body (2), the first cover body (2) is formed in a rod shape and one end of which is connected to one end of the housing (1), the first cover body (2) defines a first installation cavity extending through the first cover body (2) in its axial direction, and a first thread (21) is provided on an inner wall surface of the first cover body (2); a dose adjustment rod (3), the dose adjustment rod (3) being movably arranged in the first installation cavity along the axial direction of the first installation cavity and having one end abutting against one end of the housing (1); a second installation cavity is defined inside the dose adjustment rod (3) and a first thread groove (31) matching with the first thread (21) is provided on the outer wall surface; the inner wall of the second installation cavity at one end away from the housing (1) extends toward the axis thereof to form a first tooth shape (32); a limiting sleeve (4), the limiting sleeve (4) being movably arranged in the second mounting cavity along the axial direction of the second mounting cavity, the limiting sleeve (4) being provided with an annular limiting portion (41), the limiting sleeve (4) defining a third mounting cavity therein and having a second thread (42) on the outer wall surface, and a second tooth shape (43) being formed at one end of the annular limiting portion (41) close to the housing (1); A double-sided gear (5), wherein two ends of the double-sided gear (5) are respectively meshed with the first tooth shape (32) and the second tooth shape (43); a limit knob (6), the limit knob (6) being movably sleeved on the limit sleeve (4) along the axial direction of the limit sleeve (4), and a second thread groove (62) cooperating with the second thread (42) being provided in the limit knob (6); A screw rod (7), the screw rod (7) being movably arranged in the third installation cavity along the axial direction of the third installation cavity and having one end connected to one end of the housing (1); an injection button (8), the injection button (8) being arranged in the second mounting cavity and protruding from the other end of the dose adjustment rod (3), and a pressing rod (83) being arranged at the center of the injection button (8); The button spring (81) is arranged between the injection button (8) and the limiting sleeve (4).

2. The adjustable dose disposable injection pen according to claim 1, characterized in that: Also includes: The guide sleeve (9) is formed into a rod shape, and an axially through fourth mounting cavity is defined in the guide sleeve (9); the guide sleeve (9) is movably arranged in the third mounting cavity along the axial direction of the third mounting cavity, and the screw rod (7) is movably arranged in the fourth mounting cavity along the axial direction of the fourth mounting cavity.

3. The adjustable dose disposable injection pen according to claim 2, characterized in that: The cross section of the fourth mounting cavity in the guide sleeve (9) is non-circular so as to prevent the screw rod (7) from rotating relative to the guide rod.

4. The adjustable dose disposable injection pen according to claim 2, characterized in that: A first boss (33) is provided at one end of the dose adjustment rod (3) away from the first tooth shape (32); the inner hole of the first boss (33) is larger than the outer diameter of the port of the limiting sleeve (4), so as to facilitate controlling the shaking amplitude of the limiting sleeve (4) near the injection needle end.

5. The adjustable dose disposable injection pen according to claim 1, characterized in that: Also includes: A button card seat (82), wherein the button card seat (82) is arranged in the third installation cavity and is movably sleeved on the pressing rod (83).

6. The adjustable dose disposable injection pen according to claim 4, characterized in that: The thread pitch of the first thread (21) is greater than the thread pitch of the second thread (42).

7. The adjustable dose disposable injection pen according to claim 2, characterized in that: Also includes: A threaded seat (91), the threaded seat (91) is formed as a cylindrical body, the threaded seat (91) is arranged at one end of the housing (1) and sleeved on the screw rod (7), and the threaded seat (91) is connected to a third tooth shape (911).

8. The adjustable dose disposable injection pen according to claim 7, characterized in that: Also includes: The elastic arm (95) has one end hinged to the guide sleeve (9) and the other end meshed with the fourth tooth of the threaded seat (91).

9. The adjustable dose disposable injection pen according to claim 1, characterized in that: Also includes: The second cover body (92) is formed as a rod body with one end open and a chamber defined inside, and the second cover body (92) is detachably sleeved on the outer shell (1).

10. The adjustable dose disposable injection pen according to claim 7, characterized in that: The limiting knob (6) is provided with a first notch (61), and the dose adjustment rod (3) is provided with a second limiting rib (34), and the second limiting rib (34) cooperates with the first notch (61) so that the limiting knob (6) can move axially along the second limiting rib (34) in the dose adjustment rod (3).

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