Dose-adjustable automatic injection pen

Abstract

The invention discloses a dose-adjustable automatic injection pen, comprising: a pen shell assembly comprising a pen shell, a rotatable knob and a pushable button; the dose adjusting assembly is linked with the knob and is used for increasing the set dose when the knob rotates towards the first direction and reducing the set dose when the knob rotates towards the second direction; the injection assembly is linked with the key and is used for realizing injection when the key is pressed; the clutch is connected between the dose adjusting assembly and the injection assembly and has a first position state and a second position state, when the key is not pressed down, the clutch is in the first position state, the clutch and the pen shell are matched for limiting, and the position of the injection assembly is kept unchanged; when the key is pressed down, the clutch is in a second position state, the clutch is disengaged from the pen shell, and the injection assembly can be used for injection. When the clutch is in the first position state, the clutch is matched with the pen shell for limiting, so that the position of the injection assembly is kept unchanged, no injection action is generated when the dosage is adjusted, and the injection precision can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and more particularly to an automatic injection pen with adjustable dosage. Background Art

[0002] With the development of medical device technology, adjustable-dose automatic injection pens are widely used in the medical field.

[0003] However, the adjustable dose automatic injection pen in the prior art is prone to affect the injection assembly when adjusting the dose, causing a small amount of liquid to come out from the injection end of the injection pen when adjusting the dose, affecting the injection accuracy.

[0004] Therefore, how to avoid the influence of dosage adjustment on injection in an adjustable-dose automatic injection pen is a problem that needs to be solved urgently by those skilled in the art. Summary of the invention

[0005] In view of this, an object of the present invention is to provide an automatic injection pen with adjustable dosage, which can avoid the influence of dosage adjustment on injection and improve the injection accuracy.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] An adjustable dose automatic injection pen comprising:

[0008] A pen housing assembly, comprising a pen housing and a rotatable knob and a depressible button respectively arranged on the pen housing;

[0009] a dose adjustment assembly, linked to the knob, for increasing the set dose when the knob is rotated in a first direction, and decreasing the set dose when the knob is rotated in a second direction opposite to the first direction;

[0010] An injection assembly, linked with the button, for achieving injection when the button is pressed;

[0011] The clutch is connected between the dosage adjustment component and the injection component, and has a first position state and a second position state. When the button is not pressed, the clutch is in the first position state, and the clutch cooperates with the pen housing to limit the position, so that the injection component maintains the same position; when the button is pressed, the clutch is in the second position state, and the clutch is released from the pen housing, so that the clutch is driven by the driving force to drive the injection component to achieve injection.

[0012] Optionally, the dosage adjustment component comprises:

[0013] a driving rod, axially connected to the button and the clutch, respectively; when the button is not pressed, the driving rod is combined with the knob, and the clutch is in the first position state; when the button is pressed, the driving rod is separated from the knob, and the clutch is in the second position state;

[0014] The sleeve is axially limited with the driving rod and has a spring sheet. The clutch is provided with a first inner one-way tooth. The spring sheet extends into the first tooth groove of the first inner one-way tooth, so that the clutch limits the rotation of the sleeve along the second direction.

[0015] A pawl device is fixedly connected to the driving rod. When the clutch is in the first position state, when the driving rod rotates along the first direction, the pawl device drives the sleeve to rotate synchronously. When the driving rod rotates along the second direction, the pawl device squeezes the spring sheet to make the spring sheet disengage from the first tooth groove, and drives the sleeve to rotate synchronously along the second direction after the spring sheet disengages from the first tooth groove.

[0016] The dosage indicator can rotate synchronously with the sleeve and can move axially relative to the sleeve, and is threadably connected to the pen housing.

[0017] Optionally, the pen housing is provided with a limiting portion for abutting against the dose indicator to stop the dose indicator from moving toward the injection end of the injection pen.

[0018] Optionally, the injection assembly comprises:

[0019] A push rod is rotatably and synchronously axially movable on the housing;

[0020] The radial wheel is circumferentially limited with the push rod, and the push rod can move axially relative to the radial wheel, and the radial wheel can rotate unidirectionally relative to the housing along the second direction; the clutch and the radial wheel are always circumferentially limited;

[0021] A dynamic elastic member with a preset torsional preload is installed between the sleeve and the pen housing so that the sleeve always has a tendency to rotate along the second direction relative to the pen housing.

[0022] Optionally, it also includes:

[0023] A stopper is threadedly connected to the push rod and circumferentially limited with the drive rod so that the two can rotate synchronously and can move axially along the drive rod. When the drive rod rotates along the first direction, the stopper is rotated and moved along the push rod away from the injection direction, so that the axial position of the stopper relative to the push rod has a corresponding relationship with the set dose of each injection of the dose indicator. When the stopper is rotated and moved to the end of the thread at the distal end of the push rod, the dose indicator reaches the total dose setting position for the final dose injection.

[0024] Optionally, the dose indicator is provided with a limiting groove, and the sleeve is provided with a convex spring piece, and the convex spring piece is used to bounce into the limiting groove after the dose indicator abuts against the limiting portion, so as to produce a collision sound to indicate that the injection is completed.

[0025] Optionally, at least two end clamps distributed along the same circumference are provided at one end of the driving rod close to the injection direction, and the outer periphery of the end clamps is provided with a first protrusion and a second protrusion spaced apart in the axial direction, and the outer periphery of the driving rod is further provided with a third protrusion spaced apart from the second protrusion in the axial direction;

[0026] The clutch is provided with a radially inwardly convex inner flange, and the inner flange and the elastic sheet are respectively arranged in the gap between the first protrusion and the second protrusion, so that the clutch, the sleeve and the driving rod are axially limitedly connected;

[0027] The pawl device is clamped in the gap between the second protrusion and the third protrusion, and one of the pawl device and the driving rod is provided with a first limiting notch, and the other is provided with a first limiting rib that cooperates with the first limiting notch to limit the position.

[0028] Optionally, the pawl device is provided with a pawl side wall located outside the spring sheet, and the wall thickness of the pawl side wall gradually increases from one side to the other side along the circumferential direction, so that when the pawl device rotates along the driving rod along the second direction, the pawl side wall squeezes the spring sheet to make the spring sheet disengage from the first tooth groove.

[0029] Optionally, the clamping claw device and the driving rod are an integrally processed structure or a split structure.

[0030] Optionally, one of the outer periphery of the end of the driving rod away from the injection direction and the knob is provided with a raised tooth, and the other is provided with a tooth groove, when the button is not pressed, the raised tooth is matched with the tooth groove, and when the button is pressed, the raised tooth is disengaged from the tooth groove;

[0031] A fourth protrusion is provided on the inner side of one end of the driving rod away from the injection direction, and the button is provided with an end convex circle, which is used to be inserted into the interior of the driving rod so that the side of the end convex circle away from the injection direction abuts against the side of the fourth protrusion facing the injection direction to limit the position;

[0032] A return spring is provided between the button and the knob for providing the button with an elastic force to move in a direction away from the injection direction so as to return the button to its original position.

[0033] Optionally, the injection assembly further comprises a cam connected to the pen housing;

[0034] The outer periphery of the push rod is provided with two rows of intermittent spiral teeth distributed along the axial direction to form an intermittent first external thread, and the cam is provided with a third internal thread for threaded connection with the first external thread, so that when the push rod rotates along the second direction under the limit of the cam, it can move axially toward the injection direction;

[0035] A first limiting guide groove extending in the axial direction is provided between the two rows of spiral teeth, and the radial wheel is provided with a radial inner protrusion for slidingly cooperating with the first limiting guide groove;

[0036] The radial wheel is also provided with an elastic arm, and the cam is provided with a second inner one-way tooth. The elastic arm cooperates with the second inner one-way tooth so that the radial wheel can rotate relative to the cam along a second direction, and emits a continuous intermittent sound when the radial wheel rotates relative to the cam to prompt injection.

[0037] Optionally, one of the radial wheel and the clutch is provided with a first internal spline, and the other is provided with a first external spline for slidingly fitting with the first internal spline, so that the clutch can move axially relative to the radial wheel and the radial wheel and the clutch always have circumferential limitation.

[0038] Optionally, the limiting portion is an inner edge annular tooth provided on the inner side wall of the pen housing and distributed in the circumferential direction, and the distal end of the inner edge annular tooth is used to stop and limit the dosage indicator; the inner edge annular tooth is also used to cooperate with a second external spline provided on the outer periphery of the clutch to limit the circumferential movement of the clutch when the clutch moves to the distal position, and when the clutch moves to the proximal position, the second external spline disengages from the inner edge annular tooth.

[0039] Optionally, a refill rack is connected to one end of the pen shell close to the injection direction, the refill rack is used for loading a cartridge bottle, the end of the refill rack close to the injection direction is used to connect a needle, the end of the refill rack away from the injection direction is provided with a raised rib and a second slot, the pen shell is provided with a third limiting notch for cooperating with the raised rib, and the cam is provided with a first hook claw for cooperating with the second slot; the raised rib protrudes from the third limiting notch, so that the raised rib is used to prevent the adjustable dose automatic injection pen from rolling.

[0040] Optionally, the pen case further includes:

[0041] The turn buckle has two boss hooks arranged opposite to each other at one end away from the injection direction, and the push rod is provided with a neck recessed groove for engaging with the boss hooks so as to limit the axial position of the turn buckle and the push rod; the turn buckle is also provided with a recess at one end away from the injection direction for the conical top of the push rod close to the injection direction to extend into; the end of the turn buckle close to the injection direction is a pushing plane for contacting the cartridge stopper of the cartridge bottle.

[0042] The adjustable dose automatic injection pen provided by the present invention, when the knob is rotated in the first direction, the dose adjustment component is linked to increase the set dose; when the knob is rotated in the second direction, the dose adjustment component is linked to reduce the set dose; that is, the set dose can be flexibly adjusted, the set dose can be increased, and the set dose can be reduced, thereby realizing two-way adjustment of the set dose, which is convenient for users to use. Moreover, when the button is pressed, the injection component can be linked to achieve injection. In addition, when the button is not pressed, since the clutch is in the first position state, at this time, the clutch and the pen shell cooperate to limit, and under the limit of the pen shell, the position of the clutch remains fixed, that is, the clutch cannot rotate at this time, so that the injection component remains in the same position. Therefore, when the button is not pressed, the dose adjustment can be achieved by twisting the knob, and the injection component remains in the same position at the same time, and no injection action will be generated, thereby avoiding the position of the injection component changing when adjusting the dose, causing liquid to seep out, and affecting the injection accuracy. When injection is needed, the button can be pressed to put the clutch in the second position. At this time, the clutch and the pen housing are released, so that the clutch is driven by the driving force to drive the injection assembly to achieve injection. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0044] Figure 1 A schematic diagram of the internal structure of an adjustable dose automatic injection pen provided by a specific embodiment of the present invention;

[0045] Figure 2 A schematic diagram of the internal structure of the adjustable-dose automatic injection pen from another perspective;

[0046] Figure 3 A schematic diagram of the exploded structure of an adjustable-dose automatic injection pen;

[0047] Figure 4 An exploded view of an adjustable dose autoinjector pen;

[0048] Figure 5 A schematic diagram of the external structure of an adjustable-dose automatic injection pen;

[0049] Figure 6 A schematic diagram of the structure when the knob is rotated in a first direction to increase the set dose;

[0050] Figure 7 A schematic diagram of the internal structure of an adjustable-dose automatic injection pen when the button is not pressed;

[0051] Figure 8 It is a schematic diagram of the combination of the driving rod and the knob;

[0052] Fig. 9 It is a schematic diagram of the coordination structure of the driving rod, the clamping claw, the sleeve and the dosage indicator;

[0053] Fig.10 It is a schematic diagram of the matching structure of the dose indicator and the pen housing;

[0054] Fig.11 is a schematic diagram of the structure when the driving rod rotates in the second direction (before the spring is retracted);

[0055] Fig.12 It is a schematic diagram of the structure when the clutch is in the remote position;

[0056] Fig.13 A schematic diagram of the internal structure of an adjustable-dose automatic injection pen when a button is pressed;

[0057] Fig.14 It is a structural schematic diagram when the clutch is in the proximal position;

[0058] Fig.15 It is a schematic diagram of the structure in which the sleeve drives the clutch, the radial wheel and the push rod to rotate in the second direction;

[0059] Fig.16 This is a schematic diagram of the internal structure of an adjustable-dose automatic injection pen when a single injection reaches the maximum dose;

[0060] Fig.17 It is a schematic diagram of the structure when the 0 scale of the dose indicator is aligned with the observation window of the pen housing;

[0061] Fig.18 It is a schematic diagram of the structure when the convex spring piece of the sleeve is ejected into the limiting groove of the dose indicator when the dose indicator is in the proximal position;

[0062] Fig.19 It is a schematic diagram of the structure of the limiter;

[0063] Fig. 20 It is a schematic diagram of the structure when the limiter and the push rod cooperate;

[0064] Fig.21 It is a schematic diagram of the structure when the limiter cooperates with the driving rod;

[0065] Fig. 22 is a schematic diagram of the structure of a dose indicator;

[0066] Fig.23 It is a schematic diagram of the structure when the dose indicator and the sleeve are assembled;

[0067] Fig.24 It is a schematic diagram of the structure when the dose indicator and the pen housing are assembled;

[0068] Fig.25 is a schematic diagram of the structure of the driving rod;

[0069] Fig.26 is a schematic diagram of the structure of the clutch;

[0070] Fig. 27 It is a structural schematic diagram of the claw device;

[0071] Fig.28 It is a schematic diagram of the structure of the sleeve;

[0072] Fig.29 It is a schematic diagram of the structure after the drive rod, clutch, sleeve and claw device are assembled;

[0073] Fig.30 for Fig.29 A structural diagram from another perspective;

[0074] Fig.31 It is a schematic diagram of the matching relationship between the drive rod, the clutch, the sleeve and the claw device after assembly;

[0075] Fig.32 It is a schematic diagram of a structure in which a driving rod and a clamping claw are integrally processed and formed.

[0076] Fig.33 It is a schematic diagram of the structure after the drive rod and the knob are assembled;

[0077] Fig.34It is a schematic diagram of the structure after the knob and the pen housing are assembled;

[0078] Fig.35 This is a schematic diagram of the structure after the drive rod, knob, button and return spring are assembled;

[0079] Fig.36 is a schematic diagram of the structure of the push rod;

[0080] Fig.37 It is a structural diagram of the cam;

[0081] Fig.38 It is a schematic diagram of the structure after the cam and push rod are assembled;

[0082] Fig.39 It is a schematic diagram of the structure of the radial wheel;

[0083] Fig.40 It is a schematic diagram of the structure after the radial wheel and the push rod are assembled;

[0084] Fig.41 It is a schematic diagram of the structure after the cam and radial wheel are assembled;

[0085] Fig.42 It is a schematic diagram of the structure after the radial wheel and the clutch are assembled;

[0086] Fig.43 It is a schematic diagram of the structure of the pen shell;

[0087] Fig.44 It is a schematic diagram of the structure when the pen housing and the clutch are assembled and the clutch is in the proximal position;

[0088] Fig.45 An exploded view of the pen case, cartridge bottle, refill holder, needle and pen cap;

[0089] Fig.46 It is a structural schematic diagram of the refill holder;

[0090] Fig.47 Schematic diagram of the internal structure of the pen shell;

[0091] Fig.48 It is a schematic diagram of the structure of the pen cap;

[0092] Fig.49 It is a schematic diagram of the structure after the pen cap and the pen core frame are assembled;

[0093] Fig.50 It is a structural schematic diagram of a turnbuckle;

[0094] Fig.51 It is a schematic diagram of the structure after the turnbuckle and the push rod are assembled;

[0095] Fig.52 It is a structural schematic diagram of an elastic power part;

[0096] Fig.53 is a schematic diagram of the structure of the shell cover;

[0097] Fig.54 It is a schematic diagram of the structure after the pen shell, shell cover and elastic power part are assembled;

[0098] Fig.55 It is a schematic diagram of the structure after the elastic power part and the sleeve are assembled.

[0099] Reference numerals:

[0100] 1-needle head; 2-cassette bottle; 3-cassette bottle plug; 4-screw; 41-recess; 42-boss hook; 43-advance plane; 5-radial wheel; 51-radial inner convex block; 52-first outer spline; 53-elastic arm; 6-clutch; 61-first inner spline; 62-second outer spline; 63-first inner one-way tooth; 64-inner flange; 7-claw device; 71-claw side wall; 72-first limit notch; 8-power elastic member; 81-first bending part; 82 - second bending part; 9 - dosage indicator; 91 - digital printing part; 92 - limiting groove; 93 - second limiting rib; 94 - second external thread; 10 - pen case; 101 - first slot; 102 - limiting part; 103 - second internal thread; 104 - observation window; 105 - annular flange; 106 - second limiting notch; 107 - fifth slot; 108 - third limiting notch; 11 - knob; 111 - tooth groove; 112 - annular groove; 12 - reset spring; 13 - pen cap; 131- groove; 132- unilateral positioning part; 14- refill holder; 141- threaded structure; 142- bump; 143- raised rib; 144- second slot; 145- long through hole; 15- cam; 151- second inner unidirectional tooth; 152- first hook; 153- second hook; 154- third inner thread; 16- stopper; 161- arrow rib position; 162- first inner thread; 17- sleeve; 171- spring piece; 172- raised spring piece ;173-second limiting guide groove;174-fourth slot;18-push rod;181-helical tooth;182-first limiting guide groove;183-neck groove;184-conical top;19-driving rod;191-end clamping claw;192-first protrusion;193-second protrusion;194-third protrusion;195-first limiting rib;196-protruding tooth;197-fourth protrusion;198-inner long groove;20-shell cover;201-third slot;202-radial flange;203-third hook claw;21-button;211-end convex circle. DETAILED DESCRIPTION

[0101] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0102] The core of the present invention is to provide an adjustable dose automatic injection pen, which can adjust the set dose in two directions.

[0103] Please refer to Figures 1 to 5 The embodiment of the present invention provides an adjustable dose automatic injection pen, comprising a pen housing assembly, a dose adjustment assembly, an injection assembly and a clutch 6. The pen housing assembly comprises a pen housing 10 and a rotatable knob 11 and a depressible button 21 respectively arranged on the pen housing 10; the dose adjustment assembly is linked with the knob 11, and is used to increase the set dose when the knob 11 is rotated in a first direction, and to reduce the set dose when the knob 11 is rotated in a second direction opposite to the first direction; the injection assembly is linked with the button 21, and is used to achieve injection when the button 21 is pressed; the clutch 6 is connected between the dose adjustment assembly and the injection assembly, and the clutch 6 has a first position state and a second position state. When the button 21 is not pressed, the clutch 6 is in the first position state, and the clutch 6 cooperates with the pen housing 10 to limit, so that the injection assembly remains in the same position; when the button 21 is pressed, the clutch 6 is in the second position state, and the clutch 6 is released from the pen housing 10, so that the clutch 6 drives the injection assembly to achieve injection under the action of the driving force.

[0104] The adjustable dose automatic injection pen, when the knob 11 is rotated in the first direction, the dose adjustment component is linked to increase the set dose; when the knob 11 is rotated in the second direction, the dose adjustment component is linked to reduce the set dose; that is, the set dose can be flexibly adjusted, the set dose can be increased, and the set dose can be reduced, thereby realizing two-way adjustment of the set dose, which is convenient for users to use. Moreover, when the button 21 is pressed, the injection component can be linked to achieve injection. In addition, when the button 21 is not pressed, since the clutch 6 is in the first position state, at this time, the clutch 6 and the pen shell 10 cooperate to limit, and under the limit of the pen shell 10, the position of the clutch 6 remains fixed, that is, the clutch 6 cannot rotate at this time, so that the injection component remains in the same position. Therefore, when the button 21 is not pressed, the dose adjustment can be achieved by twisting the knob 11, and the injection component remains in the same position at the same time, and no injection action will be generated, thereby avoiding the change of the injection component position when adjusting the dose, resulting in liquid seepage, and affecting the injection accuracy. When injection is needed, the button 21 can be pressed to put the clutch 6 in the second position. At this time, the clutch 6 is released from the pen housing 10, so that the clutch 6 is driven by the driving force to drive the injection assembly to achieve injection.

[0105] It should be noted that the present embodiment does not limit the specific structure of the dosage adjustment component, as long as bidirectional dosage adjustment can be achieved.

[0106] In some embodiments, the dose adjustment assembly includes a drive rod 19, a sleeve 17, a claw device 7 and a dose indicator 9. The drive rod 19 is axially connected to the button 21 and the clutch 6 respectively. When the button 21 is not pressed, the drive rod 19 is combined with the knob 11, and the clutch 6 is in the first position state; when the button 21 is pressed, the drive rod 19 is separated from the knob 11, and the clutch 6 is in the second position state; the sleeve 17 is axially limited with the drive rod 19, the sleeve 17 has a spring sheet 171, and the clutch 6 is provided with a first inner one-way tooth 63, and the spring sheet 171 extends into the first tooth groove of the first inner one-way tooth 63, so that the clutch The device 6 limits the rotation of the sleeve 17 along the second direction; the pawl device 7 is fixedly connected to the driving rod 19. When the clutch is in the first position, when the driving rod 19 rotates along the first direction, the pawl device 7 drives the sleeve 17 to rotate synchronously. When the driving rod 19 rotates along the second direction, the pawl device 7 squeezes the spring piece 171 to make the spring piece 171 disengage from the first tooth groove, and drives the sleeve 17 to rotate synchronously along the second direction after the spring piece 171 disengages from the first tooth groove; the dosage indicator 9 can rotate synchronously with the sleeve 17, and the dosage indicator 9 can move axially relative to the sleeve 17, and the dosage indicator 9 is threadedly connected to the pen housing 10.

[0107] It should be noted that, for the convenience of description, the proximal end in the embodiment of the present invention refers to the end close to the injection end of the adjustable dose automatic injection pen, that is, the end close to the injection direction; the distal end refers to the end away from the injection end of the adjustable dose automatic injection pen, that is, the end away from the injection direction; the axial direction refers to the length direction of the adjustable dose automatic injection pen, and the circumferential direction refers to the circumferential direction of the adjustable dose automatic injection pen. In addition, the first direction and the second direction in the embodiment of the present invention refer to two opposite directions, for example, the first direction is the clockwise direction, and the first direction is the direction of increasing the dose; the second direction is the counterclockwise direction, and the second direction is the direction of decreasing the dose. At the same time, the second direction is also the rotation direction of the injection assembly during injection.

[0108] It should be noted that the clutch 6 and the sleeve 17 are respectively fixed axially relative to the drive rod 19, that is, the clutch 6 and the sleeve 17 can respectively make axial movements synchronously with the drive rod 19, while the clutch 6 and the sleeve 17 can respectively rotate circumferentially relative to the drive rod 19; the pawl device 7 is fixedly connected to the drive rod 19, so the pawl device 7 can move axially synchronously with the drive rod 19 and can rotate circumferentially synchronously with the drive rod 19.

[0109] It can be understood that the knob 11, the drive rod 19, the sleeve 17, the catch 7 and the dose indicator 9 cooperate to form a dose adjustment assembly, so that the set dose of a single injection of the adjustable dose automatic injection pen is adjustable. When the knob 11 is rotated in a first direction, the set dose increases, and when the knob 11 is rotated in a second direction, the set dose decreases.

[0110] Specifically, when the set dose needs to be adjusted and increased, the knob 11 is rotated in the first direction (eg Figure 6 As shown), note that button 21 is not pressed at this time (as shown Figure 7 As shown), at this time, the driving rod 19 is combined with the knob 11 (as shown Figure 8 As shown), the knob 11 drives the drive rod 19 to rotate in the first direction, the drive rod 19 drives the pawl device 7 to rotate synchronously, and the pawl device 7 drives the sleeve 17 to rotate synchronously (the clutch 6 and the sleeve 17 are connected by the first inner one-way tooth 63 and the spring 171, the clutch 6 limits the rotation of the sleeve 17 in the second direction, and has no limit on the rotation of the sleeve 17 in the first direction. Therefore, when the clutch 6 is in the first position, the sleeve 17 can rotate in the first direction relative to the clutch 6), and the sleeve 17 drives the dose indicator 9 to rotate synchronously (as shown). Fig. 9 As shown), the dose indicator 9 makes a spiral motion relative to the pen housing 10 (as shown Fig.10 As shown), that is, the dose indicator 9 rotates in the first direction while making axial movement, so that the dose indicator 9 is axially displaced away from the injection direction, thereby achieving the purpose of increasing the set dose.

[0111] Please refer to Fig.11 When it is necessary to adjust and reduce the set dose, the knob 11 is rotated in the second direction. Note that the button 21 is not pressed at this time. At this time, the driving rod 19 is combined with the knob 11, so that the knob 11 drives the driving rod 19 to rotate in the second direction, and the driving rod 19 drives the pawl device 7 to rotate synchronously. The pawl device 7 retracts the spring piece 171 of the sleeve 17, so that the sleeve 17 is disengaged from the clutch 6. Therefore, after the spring piece 171 is retracted, the pawl device 7 can drive the sleeve 17 to rotate synchronously in the second direction, and the sleeve 17 drives the dose indicator 9 to rotate synchronously, so that the dose indicator 9 makes a spiral motion relative to the pen housing 10, that is, the dose indicator 9 rotates in the second direction while making an axial motion, so that the dose indicator 9 produces an axial displacement toward the injection direction, thereby achieving the purpose of reducing the set dose.

[0112] During the process that the knob 11 drives the driving rod 19 to move in the first direction and in the second direction, the button 21 is not pressed. Fig.12, the clutch 6 is located at the distal position, that is, the clutch 6 is located in the first position state. At this time, the clutch 6 is combined with the pen housing 10. Under the limit of the pen housing 10, the clutch 6 cannot rotate with the drive rod 19, so that the injection component maintains the same position. Therefore, in the process of setting the dose adjustment, whether the set dose is increased or decreased, the injection component will not produce any axial displacement, and therefore will not produce any injection activity.

[0113] When the dose adjustment is completed and the injection is required, press button 21 (such as Fig.13 As shown), the button 21 drives the driving rod 19 to move axially toward the proximal end synchronously, so that the driving rod 19 is separated from the knob 11. At the same time, the driving rod 19 drives the clutch 6, the sleeve 17 and the claw device 7 to move axially toward the proximal end synchronously. Please refer to Fig.14 , so that the clutch 6 moves to the proximal position and is in the second position state, thereby separating the clutch 6 from the pen housing 10 and releasing the circumferential limiting effect of the pen housing 10 on the clutch 6. At this time, the clutch 6 can rotate freely to avoid interfering with the action of the injection assembly, so that the injection assembly can be injected.

[0114] It can be seen from this that the adjustable dose automatic injection pen can realize flexible adjustment of the set dose, and can increase the set dose or reduce the set dose, thereby realizing bidirectional adjustment of the set dose, which is convenient for users to use. When reducing the set dose, the embodiment of the present invention utilizes the rotation of the pawl device 7 to first compress and retract the spring piece 171 of the sleeve 17, so that the spring piece 171 is separated from the clutch 6, and after the spring piece 171 is retracted, the pawl device 7 drives the sleeve 17 to rotate in the second direction, that is, when the spring piece 171 is retracted, the sleeve 17 is relatively rotated relative to the clutch 6 in the second direction, thereby reducing the resistance generated by the clutch 6 when the sleeve 17 rotates in the second direction, so that the resistance during the operation of reducing the set dose is small, and the adjustment force of reducing the set dose is smoother and more stable. Moreover, when increasing the set dose, the drive rod 19 rotates in the first direction, so that the pawl device 7 drives the sleeve 17 to rotate synchronously in the first direction. At this time, the spring piece 171 is combined with the clutch 6, and the two can only rotate unidirectionally in the second direction synchronously. Therefore, when the clutch 6 is limited by the pen housing 10, the sleeve 17 cannot rotate in the second direction at this time, that is, in the process of increasing the set dose, the sleeve 17 can be prevented from rotating in the second direction, thereby ensuring the accuracy of the adjustment of increasing the set dose.

[0115] In addition, the above embodiment does not limit the specific structure of the injection component, as long as the injection component can achieve injection.

[0116] In some embodiments, the injection assembly includes a push rod 18, a radial wheel 5 and a power elastic member 8. The push rod 18 is rotatable and synchronously axially movable on the housing 10. For example, the push rod 18 is threadedly connected to the housing 10; the radial wheel 5 and the push rod 18 are circumferentially limited, and the push rod 18 can move axially relative to the radial wheel 5, and the radial wheel 5 can rotate unidirectionally in a second direction relative to the housing 10; the clutch 6 and the radial wheel 5 are always circumferentially limited; the power elastic member 8 has a preset torsional preload and is installed between the sleeve 17 and the pen housing 10, so that the sleeve 17 always has a tendency to rotate in the second direction relative to the pen housing 10.

[0117] It can be understood that, in the process that the knob 11 drives the driving rod 19 to move in the second direction and in the first direction, the button 21 is not pressed. At this time, the clutch 6 is in the first position state, and the clutch 6 is combined with the pen housing 10. Under the limitation of the pen housing 10, the clutch 6 cannot rotate with the driving rod 19, and the clutch 6 and the radial wheel 5 are always circumferentially limited, and the two rotate or stop synchronously, and the radial wheel 5 is circumferentially limited with the push rod 18. Therefore, when the clutch 6 is combined with the pen housing 10, the push rod 18 cannot rotate. Since the push rod 18 is threadedly connected to the housing 10, the push rod 18 rotates and moves axially when it moves. Therefore, when the push rod 18 cannot rotate, the axial position of the push rod 18 is also limited and cannot move. That is, in the process of setting the dose adjustment, whether the set dose is increased or decreased, the push rod 18 will not produce any axial displacement, so no injection activity will occur.

[0118] In addition, during injection, press button 21 (such as Fig.13 As shown), the driving rod 19 drives the clutch 6, the sleeve 17 and the claw device 7 to move axially toward the injection end synchronously, please refer to Fig.14 , so that the clutch 6 moves to the second position state, so that the clutch 6 is separated from the pen housing 10, and the circumferential limiting effect of the pen housing 10 on the clutch 6 is released. At this time, under the action of the power elastic member 8, as shown in Fig.15 As shown, the sleeve 17 rotates in the first direction, the sleeve 17 drives the clutch 6 to rotate synchronously, the clutch 6 drives the radial wheel 5 to rotate synchronously relative to the pen housing 10 in the first direction, and then the radial wheel 5 drives the push rod 18 to rotate synchronously. Since the push rod 18 is threadedly connected to the pen housing 10, the push rod 18 rotates while making axial movement toward the injection end, generating axial displacement, thereby realizing the injection process (such as Fig.16 In this process, the sleeve 17 drives the dose indicator 9 to rotate synchronously, so that the dose indicator 9 performs a spiral motion relative to the pen housing 10, that is, the dose indicator 9 rotates in the first direction while performing an axial motion.

[0119] In order to facilitate the limitation of the movement of the dose indicator 9 toward the injection end, in some embodiments, the pen housing 10 is provided with a limiting portion 102 for contacting with the dose indicator 9 to stop the dose indicator 9 from moving toward the injection end. That is, when the dose indicator 9 rotates in the first direction while making axial movement, the dose indicator 9 is axially displaced in the direction close to the limiting portion 102 until the dose indicator 9 contacts the limiting portion 102 of the pen housing 10. Under the limitation of the limiting portion 102, the dose indicator 9 stops rotating, so that the sleeve 17 and the push rod 18 both stop rotating, and the injection is completed, indicating that the set dose of injection liquid has been injected. It can be understood that in this process, the sleeve 17 will drive the pawl 7 to rotate in the first direction together, so that the drive rod 19 rotates in the first direction synchronously, and at this time the drive rod 19 is separated from the knob 11 to prevent the knob 11 from affecting the rotation of the drive rod 19. It can be seen that in this embodiment, when the push rod 18 is moved axially for injection, the limit of the dose indicator 9 and the pen housing 10 is used to determine the completion of a single injection, and when the set dose is adjusted by adjusting the axial position of the dose indicator 9, the axial position of the push rod 18 remains unchanged. Therefore, multiple injections can be achieved by adjusting the dose indicator 9 multiple times, thereby achieving multi-dose injection.

[0120] Also, please refer to Fig.16In order to limit the final dose of the last injection of the syringe, in some embodiments, the adjustable dose automatic injection pen also includes a limiter 16, which is threadedly connected to the push rod 18, and the limiter 16 and the drive rod 19 are circumferentially limited so that the two can rotate synchronously, and the limiter 16 can move axially along the drive rod 19. When the drive rod 19 rotates along the first direction, the limiter 16 is rotated and moved along the push rod 18 away from the injection direction, so that the axial position of the limiter 16 relative to the push rod 18 has a corresponding relationship with the set dose of each injection of the dose indicator 9. When the limiter 16 rotates and moves to the end of the thread of the push rod 18, the dose indicator 9 reaches the total dose setting position of the final dose injection. That is to say, when the push rod 18 is fixed, the limiter 16 will rotate synchronously with the rotation of the drive rod 19, that is, in the process of adjusting the dose, the limiter 16 will make axial movement on the push rod 18. When the dose is increased, the limiter 16 moves away from the injection end, and when the dose is reduced, the limiter 16 moves toward the injection end. In this embodiment, the distal position of the stopper 16 is used to limit the total set dose of the final dose injection of the syringe. It can be understood that when the drive rod 19 is rotated in the first direction to increase the set dose, the stopper 16 rotates relative to the push rod 18 and moves toward the distal end of the push rod 18. When a single injection is completed, the stopper 16 will stay at the position corresponding to the dose adjusted last for the injection, that is, at the relative axial position of the push rod 18; when the syringe is almost finished, when the last dose of the injection is adjusted, the stopper 16 will reach the end of the thread distally. When the stopper 16 reaches the end of the thread distally of the push rod 18, the stopper 16 cannot continue to rotate. Since the stopper 16 and the drive rod 19 are circumferentially limited, the drive rod 19 cannot continue to rotate in the first direction, thereby limiting the distal position of the dose indicator 9, that is, limiting the maximum dose of the dose indicator 9. In addition, it can be understood that when the button 21 is pressed, the push rod 18 rotates and moves axially toward the proximal end for injection, and the stopper 16 moves synchronously with the push rod 18. In addition, the proximal position of the stopper 16 is limited by the radial wheel 5, that is, when the injection is completed, the push rod 18 moves to the proximal position and stops advancing. At this time, the stopper 16 abuts against the radial wheel 5 to play a limiting role.

[0121] Please refer to Fig.19 , Fig. 20 and Fig.21In some embodiments, the inner circumferential surface of the stopper 16 is provided with a first internal thread 162 for threaded connection with the first external thread of the push rod 18, so that the stopper 16 must simultaneously perform circumferential rotation when performing axial movement on the push rod 18, so that the stopper 16 can perform axial movement on the push rod 18 along with the rotation of the drive rod 19. In other embodiments, the outer side of the stopper 16 is provided with an arrow rib 161 symmetrical about the axis of the stopper 16, and the inner side of the drive rod 19 is provided with a symmetrical inner long groove 198 extending along its axial direction, and the arrow rib 161 and the inner long groove 198 are slidably matched. That is, in this embodiment, through the sliding match between the arrow rib 161 and the inner long groove 198, the stopper 16 is limited to be axially movable relative to the drive rod 19, and can be synchronously rotated with the drive rod 19, and the structure is simple and easy to implement.

[0122] When adjusting the set dose, in order to facilitate the user to observe the set dose at any time, please refer to Fig.17 In some embodiments, the dose indicator 9 is provided with a digital printing part 91, and the pen housing 10 is provided with an observation window 104, and the observation window 104 is used to observe the dose value of the part where the digital printing part 91 is aligned with the observation window 104. That is, when adjusting the set dose, the dose indicator 9 rotates so that different parts of the digital printing part 91 are aligned with the observation window 104, and the dose value aligned with the observation window 104 is observed through the observation window 104 to determine whether the required set dose is reached. When the required set dose is reached, the knob 11 can be stopped from rotating in time. It should be noted that the observation window 104 can be a naked clearance through hole, or a transparent member provided at the clearance through hole.

[0123] It should be noted that, in the initial state, the 0 scale of the dose indicator 9 is aligned with the observation window 104 (eg Fig.17 As shown), at this time, the dose indicator 9 abuts against the limiting portion 102 of the pen housing 10 (as shown Fig.18 As shown); when the injection dose is set by rotating the knob 11, the dose indicator 9 rotates away from the limiting portion 102 of the pen housing 10 until the required injection dose is reached. At this time, the set dose scale is aligned with the observation window 104, the knob 11 is stopped from being rotated, and then the button 21 is pressed to inject. When the injection is completed, the dose indicator 9 abuts against the limiting portion 102 of the pen housing 10. At this time, the 0 scale of the dose indicator 9 is aligned with the observation window 104.

[0124] Please refer to Fig. 22 and Fig.23 In order to more intuitively remind the user that the injection is completed, in some embodiments, the dose indicator 9 is provided with a limit groove 92, and the sleeve 17 is provided with a convex spring piece 172, which is used to bounce into the limit groove 92 after the dose indicator 9 abuts against the limit portion 102 (please refer to Fig.18), to produce a collision sound, indicating that the injection is completed. That is to say, when each injection is completed, the dose indicator 9 will move to the position where the proximal end abuts against the limiting portion 102 of the pen housing 10. At this time, the convex spring piece 172 of the sleeve 17 will bounce into the limiting groove 92, thereby issuing a prompt sound of injection completion, giving the user the most direct injection completion response, which is convenient for the user to confirm that the injection is completed. The structure is simple and does not require excessive size control and complex product appearance to achieve.

[0125] In addition, please continue to refer to Fig.23 In order to realize the connection between the dose indicator 9 and the sleeve 17, in some embodiments, one of the outer side of the sleeve 17 and the inner side of the dose indicator 9 is provided with a second limiting rib 93 extending in the axial direction, and the other is provided with a second limiting guide groove 173 for slidingly cooperating with the second limiting rib 93. That is to say, in this embodiment, the sleeve 17 and the dose indicator 9 are limited in the circumferential direction by the cooperation and limitation of the second limiting rib 93 and the second limiting guide groove 173, so that the dose indicator 9 and the sleeve 17 can rotate synchronously. At the same time, through the sliding cooperation of the second limiting rib 93 and the second limiting guide groove 173, the dose indicator 9 can make axial movement relative to the sleeve 17 during the synchronous rotation process with the sleeve 17.

[0126] Also, please refer to Fig.24 In order to achieve the connection between the dose indicator 9 and the pen housing 10, in some embodiments, the interior of the pen housing 10 is provided with a second internal thread 103, and the outer periphery of the dose indicator 9 is provided with a second external thread 94 for threaded connection with the second internal thread 103, so that the dose indicator 9 can move axially and rotate circumferentially at a specific pitch in the pen housing 10.

[0127] It should be noted that the above embodiment does not limit the specific connection method between the drive rod 19 and the clutch 6, sleeve 17 and the pawl device 7, as long as the connection between the drive rod 19 and the clutch 6, sleeve 17 and the pawl device 7 can meet the corresponding connection requirements.

[0128] Please combine Figure 25 to Figure 29In some embodiments, the proximal end of the driving rod 19 is provided with at least two end clamps 191 distributed along the same circumference, the outer periphery of the end clamps 191 is provided with a first protrusion 192 and a second protrusion 193 arranged at intervals along the axial direction, and the outer periphery of the driving rod 19 is also provided with a third protrusion 194 arranged at intervals along the axial direction with the second protrusion 193; the clutch 6 is provided with a radially inwardly convex inner flange 64, the inner flange 64 and the spring piece 171 of the sleeve 17 are respectively arranged in the gap between the first protrusion 192 and the second protrusion 193, so that the clutch 6, the sleeve 17 and the driving rod 19 are axially limited and connected; the pawl device 7 is stuck in the gap between the second protrusion 193 and the third protrusion 194, and one of the pawl device 7 and the driving rod 19 is provided with a first limiting notch 72, and the other is provided with a first limiting rib 195 that cooperates with the first limiting notch 72 for limiting. That is to say, in this embodiment, the clutch 6, the sleeve 17 and the driving rod 19 are connected together by the end clamp 191 cooperating with the first protrusion 192 and the second protrusion 193, so that the axial positions of the clutch 6, the sleeve 17 and the driving rod 19 are relatively fixed, and the clutch 6 and the sleeve 17 can respectively rotate circumferentially relative to the driving rod 19. In addition, the second protrusion 193 and the third protrusion 194 are used to realize the axial fixation of the pawl device 7 and the driving rod 19, and the circumferential fixation of the pawl device 7 and the driving rod 19 is realized by the cooperation of the first limiting rib 195 and the first limiting notch 72, so that the pawl device 7 and the driving rod 19 are completely fixed, so that the pawl device 7 can rotate with the driving rod 19.

[0129] For further information, please refer to Fig.30 and Fig.31 In some embodiments, the clutch 6 is provided with a first inner unidirectional tooth 63 for cooperating with the spring sheet 171 of the sleeve 17, and the pawl device 7 is provided with a pawl side wall 71 located outside the spring sheet 171, and the wall thickness of the pawl side wall 71 gradually increases from one side to the other side along the circumferential direction, so that when the pawl device 7 rotates along the second direction with the driving rod 19, the pawl side wall 71 squeezes the spring sheet 171 to retract the spring sheet 171. That is to say, in this embodiment, when the spring sheet 171 is extended outward, the spring sheet 171 cooperates with the first inner unidirectional tooth 63, so that the sleeve 17 and the clutch 6 can rotate synchronously in the circumferential direction. In addition, by utilizing the thickness change of the pawl side wall 71, when the pawl device 7 rotates along the second direction with the driving rod 19, the pawl side wall 71 gradually squeezes the spring sheet 171 to retract it, and when the spring sheet 171 retracts, the spring sheet 171 is separated from the first inner unidirectional tooth 63, so that the rotation of the sleeve 17 is not restricted by the clutch 6.

[0130] For further information, please refer to Fig.33Considering the convenience of assembly, in some embodiments, the pawl device 9 and the driving rod 5 are integrally processed and formed. That is to say, in this embodiment, the structure of the pawl device 9 is integrated on the driving rod 5, so that the pawl device 9 and the driving rod 5 are combined into an integrated structure. In this way, during assembly, the pawl device 9 and the driving rod 5 can be avoided, the assembly steps are reduced, the assembly process is simplified, the injection device is convenient to assemble, and the assembly efficiency is improved.

[0131] Of course, if Fig.25 , Fig. 27 , Figure 29-31 As shown, the specific connection structure when the clamping claw device 9 and the driving rod 5 are of a split structure is given.

[0132] In addition, the above embodiments do not limit the specific connection method between the knob 11 and the driving rod 19. Fig.33 In some embodiments, one of the outer peripheral portion of the distal end of the drive rod 19 and the knob 11 is provided with a protruding tooth 196, and the other is provided with a tooth groove 111. When the button 21 is not pressed, the protruding tooth 196 cooperates with the tooth groove 111, and when the button 21 is pressed, the protruding tooth 196 is disengaged from the tooth groove 111. It can be understood that when the drive rod 19 is at the distal position, the button 21 is not pressed, and the protruding tooth 196 cooperates with the tooth groove 111, so that the drive rod 19 and the knob 11 are engaged, so that the drive rod 19 and the knob 11 can rotate synchronously, that is, when the knob 11 is turned, the drive rod 19 can be driven to rotate, so that the dose can be adjusted. When the button 21 is pressed to move the drive rod 19 from the distal position to the proximal position, the protruding tooth 196 disengages from the tooth groove 111, so that the drive rod 19 and the knob 11 can rotate relative to each other, so that the knob 11 does not rotate synchronously when the drive rod 19 rotates.

[0133] In addition, considering the specific arrangement of the knob 11 on the pen housing 10, please refer to Fig.34 In some embodiments, one of the knob 11 and the pen housing 10 is provided with an annular groove 112, and the other is provided with an annular flange 105 for slidingly cooperating with the annular groove 112. That is, the axial position of the knob 11 and the pen housing 10 is limited by the cooperation between the annular flange 105 and the annular groove 112, and the knob 11 can rotate freely on the pen housing 10 by making the annular flange 105 and the annular groove 112 relatively slidable.

[0134] In addition, the above embodiments do not limit the specific connection method between the button 21 and the driving rod 19. Fig.35In some embodiments, a fourth protrusion 197 is provided on the inner side of the distal end of the driving rod 19, and an end convex circle 211 is provided on the proximal end of the button 21. The end convex circle 211 is used to be inserted into the distal end of the driving rod 19 so that the side of the end convex circle 211 facing the distal end and the side of the fourth protrusion 197 facing the proximal end can abut and limit. In other words, in this embodiment, the side of the end convex circle 211 facing the distal end and the side of the fourth protrusion 197 facing the proximal end of the driving rod 19 are abutted and limited to limit the axial position of the button 21 and prevent the button 21 from detaching from the driving rod 19.

[0135] For further information, please refer to Fig.35 In some embodiments, a return spring 12 is provided between the button 21 and the knob 11. The return spring 12 is used to provide elastic force to the button 21 to move toward the distal end so as to reset the button 21. That is, when the button 21 is not pressed, the button 21 maintains its distal position under the action of the return spring 12. When the button 21 is pressed, the return spring 12 is squeezed. When the button 21 is released, the elastic force of the return spring 12 causes the button 21 to return to the distal position. In this process, the button 21 drives the driving rod 19 to engage with the knob 11.

[0136] Also, please refer to Figures 36 to 42 In order to facilitate the threaded connection between the push rod 18 and the pen housing 10 and the unidirectional rotation of the radial wheel 5 relative to the pen housing 10, in some embodiments, the injection assembly further includes a cam 15 connected to the pen housing 10; the outer periphery of the push rod 18 is provided with two rows of axially distributed helical teeth 181 to form a discontinuous first external thread, and the cam 15 is provided with a third internal thread 154 for engaging with the first external thread, so that when the push rod 18 rotates in the second direction, it moves axially toward the proximal end under the limit of the cam 15. Further, in some embodiments, a first limiting guide groove 182 extending in the axial direction is provided between the two rows of helical teeth 181, and the radial wheel 5 is provided with a radial inner protrusion 51 for slidingly cooperating with the first limiting guide groove 182. That is, this embodiment utilizes the cooperation of the radial inner protrusion 51 and the first limiting guide groove 182 to achieve the circumferential limit of the radial wheel 5 and the push rod 18, so that the radial wheel 5 can rotate synchronously with the push rod 18, and at the same time, the radial wheel 5 can move axially relative to the push rod 18. Furthermore, in some embodiments, the radial wheel 5 is provided with an elastic arm 53, and the cam 15 is provided with a second inner one-way tooth 151. The elastic arm 53 cooperates with the second inner one-way tooth 151 to allow the radial wheel 5 to rotate relative to the cam 15 along the second direction. When the radial wheel 5 rotates relative to the cam 15, a continuous intermittent sound will be emitted, which can indicate that an injection is being made. When the radial wheel 5 stops rotating, the continuous intermittent sound will end, which means that the injection has stopped. Therefore, this can also indicate whether the injection is completed.

[0137] Further, in some embodiments, the cam 15 is provided with a stop limiter 102, which is located at the proximal side of the second inner unidirectional tooth 151, and is used to axially limit the proximal end of the radial wheel 5. Further, in some embodiments, one of the radial wheel 5 and the clutch 6 is provided with a first internal spline 61, and the other is provided with a first external spline 52 for slidingly cooperating with the first internal spline 61, so that the clutch 6 can move axially relative to the radial wheel 5, and the radial wheel 5 and the clutch 6 always have circumferential limit. That is, the radial wheel 5 and the clutch 6 can slide relative to each other in the axial direction, but the two are never separated, so that the radial wheel 5 and the clutch 6 can always keep synchronous rotation or synchronous stop.

[0138] In addition, in order to realize the connection between the cam 15 and the pen housing 10, please refer to Fig.41 and Fig.43 In some embodiments, the cam 15 is provided with a second hook 153, and the pen housing 10 is provided with a first slot 101 for engaging with the second hook 153, so that the cam 15 and the pen housing 10 are completely fixed. That is, this embodiment utilizes the cooperation between the second hook 153 and the first slot 101 to simultaneously achieve axial and circumferential positioning of the cam 15 and the pen housing 10.

[0139] In addition, in order to facilitate the axial positioning of the clutch 6 and the dose indicator 9, please refer to Fig.44 In some embodiments, the limiting portion 102 of the pen housing 10 is an inner edge annular tooth disposed on the inner side wall of the pen housing 10 and distributed in the circumferential direction, and the distal end of the inner edge annular tooth is used to stop and limit the dose indicator 9; the inner edge annular tooth is also used to cooperate with the second external spline 62 disposed on the outer periphery of the clutch 6 to limit the circumferential movement of the clutch 6 when the clutch 6 moves to the distal position, and the second external spline 62 is disengaged from the inner edge annular tooth when the clutch 6 moves to the proximal position. In other words, the limiting portion 102 in this embodiment not only plays the role of axially limiting the proximal position of the dose indicator 9, but also plays the role of axially limiting the distal position of the clutch 6. That is, during injection, when the proximal end of the dose indicator 9 abuts against the distal end of the inner edge annular tooth, the injection is completed. In addition, when the clutch 6 is located at the distal position, the circumferential limitation of the clutch 6 and the pen housing 10 is achieved through the cooperation between the inner edge annular teeth and the second external splines 62, so that the clutch 6 cannot rotate under the limitation of the pen housing 10. When the inner edge annular teeth are disengaged from the second external splines 62, the circumferential limitation between the clutch 6 and the pen housing 10 is released, so that the clutch 6 can rotate relative to the pen housing 10.

[0140] In addition, to facilitate the installation of cartridge 2, please refer to Figure 45 to Figure 47In some embodiments, the proximal end of the pen housing 10 is connected to a cartridge holder 14, the cartridge holder 14 is used for loading the cartridge bottle 2 from its distal end, the proximal end of the cartridge holder 14 is used for connecting the needle 1, the distal end of the cartridge holder 14 is provided with a raised rib 143 and a second slot 144, the pen housing 10 is provided with a third limiting notch 108 for cooperating with the raised rib 143, and the cam 15 is provided with a first hook 152 (such as Fig.37 As shown). During assembly, the cartridge bottle 2 is first loaded into the refill frame 14 from the distal end of the refill frame 14, and then the protruding rib 143 of the refill frame 14 is aligned with the third limiting notch 108 to make the refill frame 14 and the pen body move relative to each other in the axial direction to achieve assembly, that is, the protruding rib 143 is inserted into the third limiting notch 108. During this process, the first hook 152 is inserted into the second slot 144 to achieve the fixation of the refill frame 14 and the cam 15, thereby achieving the fixation of the refill frame 14 and the pen body. In addition, the protruding rib 143 protrudes from the third limiting notch 108, so that the protruding rib 143 is used to prevent the adjustable dose automatic injection pen from rolling. That is, when the adjustable dose automatic injection pen is placed on an inclined desktop, the adjustable dose automatic injection pen can be prevented from rolling onto the ground due to the action of the protruding rib 143.

[0141] Please continue to refer to Fig.46 In some embodiments, the proximal end of the cartridge holder 14 is provided with a threaded structure 141 for threaded connection with the needle 1. In some embodiments, the needle 1 is a disposable needle 1. In addition, in some embodiments, the side wall of the cartridge holder 14 is provided with a long through hole 145 extending along its length direction, and the long through hole 145 is used to observe the position of the cartridge plug 3 of the cartridge 2, so that the user can understand the remaining situation of the liquid medicine in the cartridge 2.

[0142] Also, please refer to Fig.48 and Fig.49 In some embodiments, the pen case 10 further includes a pen cap 13 detachably mounted on the outer periphery of the pen core frame 14, so that the pen cap 13 can be used to cover the needle 1 and the pen core frame 14 when the adjustable dose automatic injection pen is not in use. Further, in some embodiments, one of the pen cap 13 and the pen core frame 14 is provided with a protrusion 142, and the other is provided with a groove 131 for matching with the protrusion 142. In some embodiments, the groove 131 is an annular groove 131, and the protrusion 142 and the annular groove 131 are loosely matched. Further, in some embodiments, a single-side positioning portion 132 is provided in the annular groove 131, which is used to limit the circumferential rotation angle of the protrusion 142 relative to the annular groove 131.

[0143] Also, please refer to Fig.50 and Fig.51In some embodiments, the adjustable dose automatic injection pen includes a turn button 4 connected to the front end of the push rod 18, the turn button 4 is located at the distal end side of the cartridge plug 3 of the cartridge bottle 2, and is used to discharge the liquid contained in the cartridge bottle 2 through the needle 1 under the action of the push rod 18. Further, in some embodiments, the distal end of the turn button 4 is provided with two bosses arranged opposite to each other, and the opposite sides of the two bosses are respectively provided with a clamping part, and the push rod 18 is provided with a neck groove 183, and the neck groove 183 is used to cooperate with the clamping part to limit the axial position of the turn button 4 at the end of the push rod 18. Further, in some embodiments, the center of the distal end of the turn button 4 is also provided with a recess 41, and the recess 41 is used for the conical top 184 of the proximal end of the push rod 18 to extend into, so as to provide support for the conical top 184 and reduce friction. In addition, in some embodiments, the proximal end of the turn button 4 is a pushing plane 43, which is used to contact the cartridge plug 3.

[0144] It should be noted that the above embodiment does not limit the preset preload force of the dynamic elastic member 8, and those skilled in the art can set it according to actual needs. In addition, the above embodiment does not limit the specific installation method of the dynamic elastic member 8, please refer to Figure 52 to Figure 55 In some embodiments, the distal end of the power elastic member 8 is provided with a first bending portion 81, the proximal end is provided with a second bending portion 82, the distal end of the pen housing 10 is provided with a housing cover 20, the housing cover 20 is provided with a third slot 201 for interlocking with the first bending portion 81, and the sleeve 17 is provided with a fourth slot 174 for interlocking with the second bending portion 82. That is, in this embodiment, the power elastic member 8 is connected to the housing cover 20 by interlocking with the first bending portion 81 and the third slot 201, that is, the power elastic member 8 is connected to the pen housing 10, and the power elastic member 8 is connected to the sleeve 17 by interlocking with the second bending portion 82 and the fourth slot 174. The power elastic member 8 has a preset preload force and is installed between the housing cover 20 and the sleeve 17. After assembly, the sleeve 17 is constantly subjected to the force applied by the power elastic member 8 to rotate in the second direction, so that the sleeve 17 always has a tendency to rotate in the second direction. In some embodiments, the power elastic member 8 is a torsion spring.

[0145] In addition, the present embodiment does not limit the specific arrangement of the shell cover 20 on the pen shell 10, as long as the shell cover 20 can be arranged on the pen shell 10. Fig.54 and Fig.43In some embodiments, the outer periphery of the shell cover 20 is provided with a third hook 203, and the pen shell 10 is provided with a fifth slot 107 for engaging with the third hook 203 to define the axial position of the shell cover 20 and the pen shell 10; the outer periphery of the shell cover 20 is provided with a radial flange 202, and the pen shell 10 is provided with a second limiting notch 106 for engaging with the radial flange 202 to define the circumferential position of the shell cover 20 and the pen shell 10. It should be noted that the specific number of the third hook 203, the fifth slot 107, the radial flange 202 and the second limiting notch 106 is not limited in this embodiment, and those skilled in the art can set them according to actual needs. For example, the number of the third hook 203 and the radial flange 202 are two respectively, the two third hooks 203 are symmetrically arranged, the two radial flanges 202 are symmetrically arranged, and the line connecting the two third hooks 203 is perpendicular to the line connecting the two radial flanges 202.

[0146] It should also be noted that, in this specification, relational terms such as first and second, etc. are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations.

[0147] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other. In the absence of contradictions, the above-mentioned embodiments can be arbitrarily combined.

[0148] The above is a detailed introduction to the adjustable dose automatic injection pen provided by the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the present invention, the present invention can also be improved and modified in a number of ways, and these improvements and modifications also fall within the scope of protection of the present invention.

Claims

1. An adjustable dose automatic injection pen, characterized in that: include: A pen housing assembly, comprising a pen housing (10) and a rotatable knob (11) and a depressible button (21) respectively arranged on the pen housing (10); a dose adjustment component, linked to the knob (11), and used to increase the set dose when the knob (11) is rotated in a first direction, and to decrease the set dose when the knob (11) is rotated in a second direction opposite to the first direction; An injection assembly, linked to the button (21), for achieving injection when the button (21) is pressed; The clutch (6) is connected between the dosage adjustment component and the injection component and has a first position state and a second position state. When the button (21) is not pressed, the clutch (6) is in the first position state, the clutch (6) cooperates with the pen housing (10) to limit the position, so that the injection component remains in the same position; when the button (21) is pressed, the clutch (6) is in the second position state, the clutch (6) is released from the pen housing (10), so that the clutch (6) drives the injection component to achieve injection under the action of the driving force.

2. The adjustable dose automatic injection pen according to claim 1, characterized in that: The dosage adjustment component comprises: a drive rod (19) axially connected to the button (21) and the clutch (6), respectively; when the button (21) is not pressed, the drive rod (19) is engaged with the knob (11), and the clutch (6) is in the first position state; when the button (21) is pressed, the drive rod (19) is separated from the knob (11), and the clutch (6) is in the second position state; The sleeve (17) is axially limited with the driving rod (19) and has a spring sheet (171). The clutch (6) is provided with a first inner one-way tooth (63). The spring sheet (171) extends into a first tooth groove of the first inner one-way tooth (63), so that the clutch (6) limits the rotation of the sleeve (17) along the second direction. a pawl device (7) fixedly connected to the driving rod (19); when the clutch is in the first position state, when the driving rod (19) rotates in the first direction, the pawl device (7) drives the sleeve (17) to rotate synchronously; when the driving rod (19) rotates in the second direction, the pawl device (7) squeezes the spring sheet (171) to make the spring sheet (171) disengage from the first tooth groove, and after the spring sheet (171) disengages from the first tooth groove, drives the sleeve (17) to rotate synchronously in the second direction; The dosage indicator (9) can rotate synchronously with the sleeve (17), can move axially relative to the sleeve (17), and is threadedly connected to the pen housing (10).

3. The injection pen with adjustable dose automatic injection pen according to claim 2, characterized in that: The pen housing (10) is provided with a limiting portion (102) for abutting against the dose indicator (9) to stop the dose indicator (9) from moving toward the injection end of the injection pen.

4. The injection pen with adjustable dose automatic injection pen according to claim 2, characterized in that: The injection assembly comprises: A push rod (18) is rotatably and synchronously axially movable on the housing (10); The radial wheel (5) is circumferentially limited with the push rod (18), and the push rod (18) can move axially relative to the radial wheel (5), and the radial wheel (5) can rotate unidirectionally along the second direction relative to the housing (10); the clutch (6) and the radial wheel (5) are always circumferentially limited; A dynamic elastic member (8) having a preset torsional preload is installed between the sleeve (17) and the pen housing (10), so that the sleeve (17) always has a tendency to rotate along the second direction relative to the pen housing (10).

5. The adjustable dose automatic injection pen according to claim 4, characterized in that: Also includes: A stopper (16) is threadedly connected to the push rod (18) and is circumferentially limited with the drive rod (19) so that the two can rotate synchronously and can move axially along the drive rod (19). When the drive rod (19) rotates in the first direction, the stopper (16) is rotated and moved along the push rod (18) away from the injection direction, so that the axial position of the stopper (16) relative to the push rod (18) has a corresponding relationship with the set dose of each injection of the dose indicator (9). When the stopper (16) rotates and moves to the end of the thread at the distal end of the push rod (18), the dose indicator (9) reaches the total dose setting position for the final dose injection.

6. The adjustable dose automatic injection pen according to claim 3, characterized in that: The dose indicator (9) is provided with a limiting groove (92), and the sleeve (17) is provided with a convex spring piece (172). The convex spring piece (172) is used to bounce into the limiting groove (92) after the dose indicator (9) abuts against the limiting portion (102), so as to generate a collision sound, indicating that the injection is completed.

7. The adjustable dose automatic injection pen according to any one of claims 2 to 6, characterized in that: The end of the driving rod (19) close to the injection direction is provided with at least two end clamps (191) distributed along the same circumference, the outer periphery of the end clamps (191) is provided with a first protrusion (192) and a second protrusion (193) arranged at intervals along the axial direction, and the outer periphery of the driving rod (19) is also provided with a third protrusion (194) arranged at intervals from the second protrusion (193) along the axial direction; The clutch (6) is provided with a radially inwardly convex inner flange (64), and the inner flange (64) and the elastic sheet (171) are respectively arranged in a gap between the first protrusion (192) and the second protrusion (193), so that the clutch (6), the sleeve (17) and the drive rod (19) are axially limitedly connected; The pawl device (7) is clamped in the gap between the second protrusion (193) and the third protrusion (194), and one of the pawl device (7) and the driving rod (19) is provided with a first limiting notch (72), and the other is provided with a first limiting rib (195) that cooperates with the first limiting notch (72) to limit the position.

8. The adjustable dose automatic injection pen according to any one of claims 2 to 6, characterized in that: The pawl device (7) is provided with a pawl side wall (71) located outside the spring sheet (171), and the wall thickness of the pawl side wall (71) gradually increases from one side to the other side along the circumferential direction, so that when the pawl device (7) rotates along the driving rod (19) along the second direction, the pawl side wall (71) presses the spring sheet (171) so that the spring sheet (171) is separated from the first tooth groove.

9. The adjustable dose automatic injection pen according to any one of claims 2 to 6, characterized in that: The claw device (7) and the driving rod (19) are an integrally processed structure or a split structure.

10. The adjustable dose automatic injection pen according to any one of claims 2 to 6, characterized in that: One of the outer peripheral portion of the end of the driving rod (19) away from the injection direction and the knob (11) is provided with a protruding tooth (196), and the other is provided with a tooth groove (111), when the button (21) is not pressed, the protruding tooth (196) is matched with the tooth groove (111), and when the button (21) is pressed, the protruding tooth (196) is disengaged from the tooth groove (111); A fourth protrusion (197) is provided on the inner side of an end of the driving rod (19) away from the injection direction, and the button (21) is provided with an end convex circle (211), and the end convex circle (211) is used to be inserted into the interior of the driving rod (19), so that the side of the end convex circle (211) away from the injection direction abuts against the side of the fourth protrusion (197) facing the injection direction to limit the position; A return spring (12) is provided between the button (21) and the knob (11) for providing the button (21) with an elastic force to move in a direction away from the injection direction so as to return the button (21).

11. The adjustable dose automatic injection pen according to claim 4, characterized in that: The injection assembly further comprises a cam (15) connected to the pen housing (10); The outer periphery of the push rod (18) is provided with two rows of intermittent spiral teeth (181) distributed along the axial direction to form an intermittent first external thread, and the cam (15) is provided with a third internal thread (154) for threaded connection with the first external thread, so that when the cam (15) is limited, the push rod (18) can move axially in the injection direction when rotating in the second direction; A first limiting guide groove (182) extending in the axial direction is provided between the two rows of spiral teeth (181), and the radial wheel (5) is provided with a radial inner protrusion (51) for slidingly cooperating with the first limiting guide groove (182); The radial wheel (5) is further provided with an elastic arm (53), and the cam (15) is provided with a second inner one-way tooth (151). The elastic arm (53) cooperates with the second inner one-way tooth (151) so that the radial wheel (5) can rotate relative to the cam (15) in a second direction, and emits a continuous intermittent sound when the radial wheel (5) rotates relative to the cam (15) to prompt injection.

12. The adjustable dose automatic injection pen according to claim 11, characterized in that: One of the radial wheel (5) and the clutch (6) is provided with a first internal spline (61), and the other is provided with a first external spline (52) for slidingly cooperating with the first internal spline (61), so that the clutch (6) can move axially relative to the radial wheel (5), and the radial wheel (5) and the clutch (6) always have circumferential limit.

13. The adjustable dose automatic injection pen according to claim 3, characterized in that: The limiting portion (102) is an inner edge annular tooth provided on the inner side wall of the pen housing (10) and distributed in the circumferential direction, the distal end of the inner edge annular tooth being used to stop and limit the dosage indicator (9); the inner edge annular tooth is also used to cooperate with a second external spline (62) provided on the outer periphery of the clutch (6) to limit the circumferential movement of the clutch (6) when the clutch (6) moves to the distal end position; when the clutch (6) moves to the proximal end position, the second external spline (62) is disengaged from the inner edge annular tooth.

14. The adjustable dose automatic injection pen according to any one of claims 1 to 6, characterized in that: The end of the pen case (10) close to the injection direction is connected to a refill frame (14), the refill frame (14) is used for loading the cartridge bottle (2), the end of the refill frame (14) close to the injection direction is used for connecting the needle (1), and the end of the refill frame (14) away from the injection direction is provided with a raised rib (143) and a second slot (144), the pen case (10) is provided with a third limiting notch (108) for cooperating and plugging with the raised rib (143), and the cam (15) is provided with a first hook (152) for cooperating and plugging with the second slot (144); the raised rib (143) protrudes from the third limiting notch (108), so that the raised rib (143) is used to prevent the adjustable dose automatic injection pen from rolling.

15. The adjustable dose automatic injection pen according to claim 14, characterized in that: The pen case (10) further comprises: The turn buckle (4) has two boss hooks (42) arranged opposite to each other at one end thereof away from the injection direction, and the push rod (18) has a neck recess (183) for engaging with the boss hooks (42) so as to limit the axial position of the turn buckle (4) and the push rod (18); the turn buckle (4) has a concave portion (41) for the conical top portion (184) of the push rod (18) near the injection direction to extend therein; and the turn buckle (4) has a thrust plane (43) for contacting the cartridge plug (3) of the cartridge bottle (2) at one end thereof away from the injection direction.

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