Adjustment feedback mechanism of injection pen

Abstract

The invention provides an injection pen adjusting feedback mechanism which comprises a metering dial support and a main shell, the metering dial support is connected with the main shell in a sleeved mode, when dosage is set, the metering dial support rotates in the first direction, a limiting piece is connected with the metering dial support at the first position, and the metering dial support rotates in the second direction. The first feedback mechanism and the second feedback mechanism rotate in a matched mode and feed back the dosage being set, when the set dosage needs to be corrected, the metering dial support rotates in the second direction, and the limiting piece and the metering dial support are connected at the second position; the dose feedback assembly on the metering dial support is contracted inwards under the matching action of the limiting piece to rotate in the second direction and feed back the dose which is being corrected and set, and due to the fact that the dose feedback assembly is contracted inwards, when the set dose is corrected, it is not strenuous to rotate the metering dial support in the second direction.

Description

Technical Field

[0001] The present invention relates to the technical field of adjustable metered injection devices, and more specifically, to an adjustment feedback mechanism of an injection pen. Background Art

[0002] The structure of an adjustable metered injection device includes a dose adjustment, an injection mechanism and a cartridge bottle fixing mechanism. When adjusting the dose, the user rotates a dose adjustment member of the dose pouring mechanism, and the force applied by the user is stored in a torsion spring. In order to pour out the adjusted dose, the user presses a pouring button on the proximal end of the syringe, and the torsion force accumulated in the torsion spring can be delivered to the driving element to drive the liquid out of the injection device.

[0003] The downward dialing mechanism of the injection device includes a ratchet arm engaging teeth on a fixed element. When the dose setting element is rotated forwardly relative to the housing, the torsion spring is tensioned to prevent the dose setting element from rotating in the reverse direction. When the dose setting element is rotated in the reverse direction, the ratchet arm disengages from the fixed element to allow the dose setting element to rotate in the reverse direction. When the dose setting element rotates forward or reversely, the ratchet arm and the teeth on the fixed element collide with each other and make a sound. However, this solution has the problems of many parts, complex assembly, high assembly difficulty, high cost, the torsion spring will explode during the pre-tightening process, and before the injection is completed, the sound-generating device will cause the rotation of the metering dial to obviously slow down first and then accelerate, the self-locking failure phenomenon, and no exhaust function. Summary of the invention

[0004] In view of the above, to solve the above problems, the present invention provides an adjustment feedback mechanism for an injection pen, including a dosing dial bracket 20 and a main housing 60. The dosing dial bracket 20 is sleeved with the main housing 60. The dosing dial bracket 20 is used to cooperate with the dosing dial 10 for dose display when adjusting the dose. A screw sleeve 30 is sleeved inside the dosing dial bracket. A dose feedback assembly is provided at the dosing dial bracket 20. A first feedback mechanism 55 is provided at the dose feedback assembly. A second feedback mechanism 70 that cooperates with the first feedback mechanism 55 is provided at the main housing 60. A limiting member 40 is provided around the screw sleeve 30. Part of the limiting member 40 is arranged outside the dose feedback assembly and has a gap. When setting the dose, the dosing dial bracket 20 rotates in a first direction, and the limiting member 40 engages with the dosing dial bracket 20 at a first position. The first feedback mechanism 55 and the second feedback mechanism 70 cooperate to rotate and feedback that the dose is being set. When it is necessary to correct the set dose, the dosing dial bracket 20 rotates in a second direction, and the limiting member 40 engages with the dosing dial bracket 20 at a second position, so that the dose feedback assembly on the dosing dial bracket 20 is contracted inward under the cooperation of the limiting member 40 to achieve rotation in the second direction and feedback that the set dose is being corrected. Since the dose feedback assembly contracts inward, when correcting the set dose, it is not very laborious for the dosing dial bracket 20 to rotate in the second direction.

[0005] An adjustment feedback mechanism for an injection pen, including a dosing dial bracket 20 and a main housing 60. The dosing dial bracket 20 is sleeved with the main housing 60. The dosing dial bracket 20 is used to cooperate with the dosing dial 10 for dose display when adjusting the dose. A screw sleeve 30 is sleeved inside the dosing dial bracket. A dose feedback assembly is provided at the dosing dial bracket 20. A first feedback mechanism 55 is provided at the dose feedback assembly. A second feedback mechanism 70 that cooperates with the first feedback mechanism 55 is provided at the main housing 60. A limiting member 40 is provided around the screw sleeve 30. Part of the limiting member 40 is arranged outside the dose feedback assembly and has a gap. When setting the dose, the dosing dial bracket 20 rotates in a first direction, and the limiting member 40 engages with the dosing dial bracket 20 at a first position. The first feedback mechanism 55 and the second feedback mechanism 70 cooperate to rotate and feedback that the dose is being set. When it is necessary to correct the set dose, the dosing dial bracket 20 rotates in a second direction, and the limiting member 40 engages with the dosing dial bracket 20 at a second position, so that the dose feedback assembly on the dosing dial bracket 20 is contracted inward under the cooperation of the limiting member 40 to achieve rotation in the second direction and feedback that the set dose is being corrected. Since the dose feedback assembly contracts inward, when correcting the set dose, it is not very laborious for the dosing dial bracket 20 to rotate in the second direction.

[0006] In some embodiments, the dose feedback assembly includes a spring arm 52 and a first feedback mechanism 55. The first feedback mechanism 55 is a detent, which is located at the free end of the outer wall of the spring arm 52. The second feedback mechanism 70 is a circle of ratchet teeth that cooperate with the detent. One unit of measurement is defined as the detent moving from one ratchet tooth to its adjacent ratchet tooth.

[0007] Furthermore, the detent is provided with a tooth edge segment 551 that engages with the ratchet teeth in the first direction. The tooth edge segment 551 abuts against one side of the ratchet teeth when the metering dial bracket 20 finishes rotating in the first direction, thereby fixing the set dose.

[0008] Furthermore, the abutting surface 71 between the tooth edge segment 551 and the ratchet teeth forms an angle greater than 45° and less than 90° with the horizontal, preventing the detent from rotating in the second direction.

[0009] Furthermore, the detent is provided with a guiding surface 552 that guides the ratchet teeth in the first direction. The guiding surface 552 impacts and contacts the other side of the ratchet teeth when the metering dial bracket 20 rotates in the first direction, causing the detent to contract inward, thereby setting the dose. And a sound feedbacking that the dose is being set is emitted due to the impact between the guiding surface 552 and the other side of the ratchet teeth.

[0010] Furthermore, the contact surface 72 between the guiding surface 552 and the ratchet teeth forms an angle greater than 90° and less than 180° with the horizontal, ensuring that the detent can rotate smoothly in the first direction for dose setting.

[0011] In some embodiments, the joint between the dose dial bracket and the limiting member 40 is a groove structure 21. When the injection pen is not in use, a part of the limiting member 40 is placed in the groove structure 21 and does not contact the two side walls of the groove structure 21. When setting the dose, the metering dial bracket 20 rotates in the first direction, and the limiting member 40 engages with one side wall of the groove structure 21 at the first position. When it is necessary to correct the set dose, the metering dial bracket 20 rotates in the second direction, and the limiting member 40 engages with the other side wall of the groove structure 21 at the second position, causing the dose feedback assembly on the metering dial bracket 20 to be contracted inward under the cooperation of the limiting member 40 to achieve rotation in the second direction and feedback that the set dose is being corrected, due to the inward contraction of the dose feedback assembly.

[0012] Furthermore, the part of the limiting member 40 in the groove structure 21 is a strip-shaped column structure.

[0013] Furthermore, only one end of the limiting member 40 is fixed to the outer wall of the metering dial bracket 20, and the rest does not contact the outer wall of the metering dial bracket 20.

[0014] Further, a protrusion 51 is provided on the outer wall of the dose feedback assembly. When it is necessary to correct the set dose, the metering dial bracket 20 rotates in the second direction. The limiting member 40 contacts the protrusion 51 and squeezes the outer wall of the protrusion 51. When the limiting member 40 engages with the other side wall of the groove structure 21 at the second position, the dose feedback assembly on the metering dial bracket 20 is contracted inward, and the teeth of the first feedback mechanism 55 can still cooperate with the ratchet teeth of the second feedback mechanism 70, generating a feel in the second direction and feeding back that the set dose is being corrected.

[0015] Further, a first arc surface 553 is provided between the tooth edge section 551 and the guiding surface 552 of the tooth. A second arc surface 73 is provided between the abutting surface 71 and the contact surface 72 of the ratchet tooth. When the metering dial bracket 20 rotates in the second direction, the first arc surface 553 contacts the second arc surface 73, and the second arc surface 73 squeezes the first arc surface 553 to make the tooth contract inward, so as to correct the set dose. When the second arc surface 73 does not squeeze the first arc surface 553, the tooth edge section 551 of the tooth impacts one side of the ratchet tooth, making a sound to feed back that the set dose is being corrected.

[0016] Further, the protrusion 51 is provided with a first curved surface 511, and the first curved surface 511 transitions from the outer wall of the metering dial bracket 20 to the highest point of the protrusion 51, so as to facilitate the contact between the limiting member 40 and the highest point of the protrusion 51.

[0017] Further, a convex block 53 is provided on the outer wall of the elastic arm 52. When the limiting member 40 moves toward the injection end along with the screw sleeve 30, the limiting member 40 squeezes the convex block 53 inward, so that the first feedback mechanism 55 is completely separated from the second feedback mechanism 70, facilitating the injection of the injection pen.

[0018] Further, the upper part of the convex block 53 is provided with a second curved surface 531, and the second curved surface 531 transitions from the outer wall of the metering dial bracket 20 to the highest point of the convex block 53, so as to facilitate the contact between the limiting member 40 and the highest point of the convex block 53.

[0019] Further, the contact part between the limiting member 40 and the convex block 53 is a first inclined surface 41 extending from the inside to the outside for guiding.

[0020] Further, the opposite surface of the first inclined surface 41 of the limiting member 40 is a second inclined surface 42, and the second inclined surface 42 is located on the outer side wall of the limiting member 40, preventing the limiting member 40 from contacting the ratchet teeth and generating friction when the limiting member 40 squeezes the convex block 53 inward, so that the first feedback mechanism 55 is completely separated from the second feedback mechanism 70, thus affecting the injection of the injection pen.

[0021] In some embodiments, a groove 56 is provided at the connection between the dose feedback component and the metering dial bracket 20 to facilitate the inward retraction of the spring arm 52.

[0022] In some embodiments, a notch 57 is further provided at the free end of the spring arm 52 to avoid the metering dial bracket 20 when adjusting the dose.

[0023] Advantages of the present invention: The present invention provides an adjustment feedback mechanism for an injection pen, including a metering dial bracket 20 and a main housing 60. The metering dial bracket 20 is sleeved with the main housing 60. The metering dial bracket 20 is used to cooperate with the metering dial 10 for dose display when adjusting the dose. A screw sleeve 30 is sleeved inside the dose dial bracket. A dose feedback component is provided at the metering dial bracket 20. A first feedback mechanism 55 is provided at the dose feedback component. A second feedback mechanism 70 cooperating with the first feedback mechanism 55 is provided at the main housing 60. A limiting member 40 is provided on the periphery of the screw sleeve 30. Part of the limiting member 40 is arranged outside the dose feedback component and has a gap. When setting the dose, the metering dial bracket 20 rotates in a first direction, and the limiting member 40 engages with the metering dial bracket 20 at a first position. The first feedback mechanism 55 and the second feedback mechanism 70 cooperate to rotate and feedback that the dose is being set. When it is necessary to correct the set dose, the metering dial bracket 20 rotates in a second direction, and the limiting member 40 engages with the metering dial bracket 20 at a second position, so that the dose feedback component on the metering dial bracket 20 is retracted inward under the cooperation of the limiting member 40 to realize rotation in the second direction and feedback that the set dose is being corrected. Since the dose feedback component retracts inward, when correcting the set dose, the metering dial bracket 20 rotates in the second direction without much effort. Description of the Drawings

[0024] Figure 1 It is the overall installation drawing of the present invention.

[0025] Figure 2 It is the perspective view of the main housing of the present invention.

[0026] Figure 3 It is the perspective view of the dose feedback component of the present invention.

[0027] Figure 4 It is the perspective view of the limiting member of the present invention.

[0028] Figure 5 It is the structural diagram of the limiting member moving downward to contact the convex block of the present invention.

[0029] Figure 6 It is the structural diagram of the limiting member moving downward to contact the main housing of the present invention.

[0030] Figure 7 Structural diagram of the toothed edge section of the first feedback mechanism of the present invention and the abutting surface of the second feedback mechanism.

[0031] Figure 8 Structural diagram of the guiding surface of the first feedback mechanism of the present invention and the guiding surface of the second feedback mechanism.

[0032] Figure 9 Structural diagram of the first arc surface of the first feedback mechanism of the present invention and the first arc surface of the second feedback mechanism.

[0033] Description of main component symbols

[0034] Dosage scale dial 10; dosage scale dial support 20; trough-shaped structure 21; screw sleeve 30; limiting member 40; first inclined surface 41; second inclined surface 42; protrusion 51; first curved surface 511; elastic arm 52; convex block 53; second curved surface 531; first feedback mechanism 55; toothed edge section 551; guiding surface 552; first arc surface 553; groove 56; notch 57; main housing 60; second feedback mechanism 70; abutting surface 71; guiding surface 72; first arc surface 73. Detailed implementation manners Embodiment:

[0035] As Figures 1-3 shown, an adjustment feedback mechanism of an injection pen includes a dosage scale dial support 20 and a main housing 60. The dosage scale dial support 20 is sleeved with the main housing 60. The dosage scale dial support 20 is used to cooperate with the dosage scale dial 10 for displaying the dosage during adjustment of the dosage. A screw sleeve 30 is sleeved inside the dosage scale dial support. A dosage feedback assembly is provided at the dosage scale dial support 20. A first feedback mechanism 55 is provided at the dosage feedback assembly. A second feedback mechanism 70 that cooperates with the first feedback mechanism 55 is provided at the main housing 60. A limiting member 40 is provided on the periphery of the screw sleeve 30. Part of the limiting member 40 is arranged outside the dosage feedback assembly and has a gap. When setting the dosage, the dosage scale dial support 20 rotates in the first direction, and the limiting member 40 engages with the dosage scale dial support 20 at the first position. The first feedback mechanism 55 and the second feedback mechanism 70 rotate in cooperation and feedback that the dosage is being set. When it is necessary to correct the set dosage, the dosage scale dial support 20 rotates in the second direction, and the limiting member 40 engages with the dosage scale dial support 20 at the second position, so that the dosage feedback assembly on the dosage scale dial support is contracted inward under the cooperation of the limiting member 40 to realize rotation in the second direction and feedback that the set dosage is being corrected. Since the dosage feedback assembly contracts inward, when correcting the set dosage, it is not very laborious for the dosage scale dial support 20 to rotate in the second direction.

[0036] As Figure 3 and Figure 7 shown, the dose feedback assembly includes a spring arm 52 and a first feedback mechanism 55. The first feedback mechanism 55 is a tooth, which is located at the free end of the outer wall of the spring arm 52. The second feedback mechanism 70 is a circle of ratchet teeth that cooperate with the tooth. One unit of measurement is when the tooth steps from one ratchet tooth to its adjacent ratchet tooth. The tooth is provided with a tooth edge section 551 that engages with the ratchet teeth in the first direction. The tooth edge section 551 abuts against one side of the ratchet teeth when the metering dial bracket 20 rotates to the end in the first direction, so as to fix the set dose. The contact surface 71 between the tooth edge section 551 and the ratchet teeth has a horizontal angle greater than 45° and less than 90°, preventing the tooth from rotating in the second direction.

[0037] As Figure 3 and Figure 8 shown, the tooth is provided with a guiding surface 552 that guides the ratchet teeth in the first direction. The guiding surface 552 impacts and contacts the other side of the ratchet teeth when the metering dial bracket 20 rotates in the first direction, causing the tooth to contract inward, so as to set the dose. And because the guiding surface 552 impacts the other side of the ratchet teeth, a sound of feedback on setting the dose is emitted. The contact surface 72 between the guiding surface 552 and the ratchet teeth has a horizontal angle greater than 90° and less than 180°, ensuring that the tooth can smoothly rotate in the first direction for dose setting.

[0038] The joint between the dose dial bracket and the limiting member 40 is a groove structure 21. When the injection pen is not in use, a part of the limiting member 40 is placed in the groove structure 21 and does not contact the two side walls of the groove structure 21. When setting the dose, the metering dial bracket 20 rotates in the first direction, and the limiting member 40 engages with one side wall of the groove structure 21 at the first position. When it is necessary to correct the set dose, the metering dial bracket 20 rotates in the second direction, and the limiting member 40 engages with the other side wall of the groove structure 21 at the second position, so that the dose feedback assembly on the metering dial bracket 20 is contracted inward under the cooperation of the limiting member 40 to realize rotation in the second direction and feedback on correcting the set dose. Since the dose feedback assembly contracts inward, the part of the limiting member 40 in the groove structure 21 is a strip-shaped column structure, and only one end of the limiting member 40 is fixed to the outer wall of the metering dial bracket 20, and the rest does not contact the outer wall of the metering dial bracket 20.

[0039] A protrusion 51 is provided on the outer wall of the dose feedback component. When it is necessary to correct the set dose, the metering dial bracket 20 rotates in the second direction. The limiting member 40 contacts the protrusion 51 and presses against the outer wall of the protrusion 51. When the limiting member 40 engages with the other side wall of the groove-shaped structure 21 at the second position, the dose feedback component on the metering dial bracket 20 is contracted inward, and the teeth of the first feedback mechanism 55 can still cooperate with the ratchet teeth of the second feedback mechanism 70, generating a feel in the second direction and feedbacking that the set dose is being corrected.

[0040] As Figure 3 and Figure 9 shown, a first arc surface 553 is provided between the tooth edge section 551 and the guiding surface 552 of the tooth. A second arc surface 73 is provided between the abutting surface 71 and the contact surface 72 of the ratchet tooth. When the metering dial bracket 20 rotates in the second direction, the first arc surface 553 contacts the second arc surface 73, and the second arc surface 73 presses against the first arc surface 553 to cause the tooth to contract inward, thereby correcting the set dose. When the second arc surface 73 does not press against the first arc surface 553, the tooth edge section 551 of the tooth impacts one side of the ratchet tooth, emitting a sound to feedback that the set dose is being corrected.

[0041] The protrusion 51 is provided with a first curved surface 511, and the first curved surface 511 transitions from the outer wall of the metering dial bracket 20 to the highest point of the protrusion 51, thereby facilitating the contact between the limiting member 40 and the highest point of the protrusion 51.

[0042] A convex block 53 is provided on the outer wall of the elastic arm 52. When the limiting member 40 moves towards the injection end along with the screw sleeve 30, the limiting member 40 presses the convex block 53 inward, causing the first feedback mechanism 55 to be completely separated from the second feedback mechanism 70, facilitating the injection of the injection pen. The upper part of the convex block 53 is provided with a second curved surface 531, and the second curved surface 531 transitions from the outer wall of the metering dial bracket 20 to the highest point of the convex block 53, thereby facilitating the contact between the limiting member 40 and the highest point of the convex block 53.

[0043] As Figure 4 and Figure 5 shown, the contact part of the limiting member 40 and the convex block 53 is a first inclined surface 41 extending from the inside to the outside for guiding.

[0044] As Figure 4 and Figure 6 shown, the opposite surface of the first inclined surface 41 of the limiting member 40 is a second inclined surface 42, and the second inclined surface 42 is located on the outer side wall of the limiting member 40 to prevent the limiting member 40 from contacting the ratchet teeth and generating friction when pressing the convex block 53 inward, causing the first feedback mechanism 55 to be completely separated from the second feedback mechanism 70, thereby affecting the injection of the injection pen.

[0045] As Figure 3 shown, a groove 56 is provided at the connection between the dose feedback component and the metering dial bracket 20, facilitating the inward retraction of the spring arm 52. A notch 57 is further provided at the free end of the spring arm 52 for avoiding the metering dial bracket 20 when adjusting the dose.

[0046] Advantages of the present invention: The present invention provides an adjustment feedback mechanism for an injection pen, including a metering dial bracket 20 and a main housing 60. The metering dial bracket 20 is sleeved with the main housing 60. The metering dial bracket 20 is used to cooperate with the metering dial 10 for dose display when adjusting the dose. A screw sleeve 30 is sleeved inside the dose dial bracket. A dose feedback component is provided at the metering dial bracket 20. A first feedback mechanism 55 is provided at the dose feedback component. A second feedback mechanism 70 cooperating with the first feedback mechanism 55 is provided at the main housing 60. A limiting member 40 is provided on the periphery of the screw sleeve 30. Part of the limiting member 40 is arranged outside the dose feedback component and has a gap. When setting the dose, the metering dial bracket 20 rotates in the first direction, and the limiting member 40 engages with the metering dial bracket 20 at the first position. The first feedback mechanism 55 and the second feedback mechanism 70 cooperate to rotate and feedback that the dose is being set. When it is necessary to correct the set dose, the metering dial bracket 20 rotates in the second direction, and the limiting member 40 engages with the metering dial bracket 20 at the second position, so that the dose feedback component on the metering dial bracket 20 is retracted inward under the cooperation of the limiting member 40 to realize rotation in the second direction and feedback that the set dose is being corrected. Since the dose feedback component retracts inward, when correcting the set dose, the rotation of the metering dial bracket 20 in the second direction is not very laborious.

[0047] The above embodiments merely represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the present invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several deformations and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be subject to the appended claims.

Claims

1. An adjustment feedback mechanism for an injection pen, comprising a metering dial bracket and a main housing, wherein the metering dial bracket is sleeved with the main housing, the metering dial bracket is used to cooperate with the metering dial to display the dose when adjusting the dose, and a screw sleeve is sleeved in the dose dial bracket, characterized in that: A dosage feedback component is provided at the metering dial bracket, a first feedback mechanism is provided at the dosage feedback component, a second feedback mechanism cooperating with the first feedback mechanism is provided at the main shell, a limiter is provided on the periphery of the screw sleeve, and a portion of the limiter is arranged on the outside of the dosage feedback component and has a gap. When setting the dose, the metering dial bracket rotates in the first direction, the limiter engages with the metering dial bracket in the first position, the first feedback mechanism cooperates with the second feedback mechanism to rotate and feedback the dose being set, and when the set dose needs to be corrected, the metering dial bracket rotates in the second direction, the limiter engages with the metering dial bracket in the second position, so that the dosage feedback component on the metering dial bracket is contracted inwardly under the cooperation of the limiter to realize the second direction rotation and feedback of the dose being corrected.

2. The adjustment feedback mechanism of the injection pen according to claim 1, characterized in that: The dosage feedback assembly includes an elastic arm and a first feedback mechanism, wherein the first feedback mechanism is a latch tooth, and the latch tooth is located at the free end of the outer wall of the elastic arm. The second feedback mechanism is a circle of ratchet teeth that cooperates with the latch tooth, and the latch tooth spans from one ratchet tooth to its adjacent ratchet tooth as one measuring unit.

3. The adjustment feedback mechanism of the injection pen according to claim 2, characterized in that: The latching tooth is provided with a tooth edge section engaged with the ratchet in the first direction, and the tooth edge section abuts against one side of the ratchet when the metering scale bracket finishes rotating in the first direction, thereby fixing the set dose.

4. The adjustment feedback mechanism of the injection pen according to claim 3, characterized in that: The latch tooth is provided with a guide surface which guides the ratchet in the first direction. When the metering scale bracket rotates in the first direction, the guide surface collides with the other side of the ratchet, causing the latch tooth to contract inwardly, thereby setting the dose. Due to the collision of the guide surface and the other side of the ratchet, a sound of feedback that the dose is being set is emitted.

5. The adjustment feedback mechanism of the injection pen according to claim 4, characterized in that: The joint between the dosage dial bracket and the limiter is a groove structure. When the injection pen is not in use, the limiter is partially placed in the groove structure and does not contact the two side walls of the groove structure. When setting the dose, the metering dial bracket rotates in a first direction, and the limiter engages with one side wall of the groove structure at a first position. When the set dose needs to be corrected, the metering dial bracket rotates in a second direction, and the limiter engages with the other side wall of the groove structure at a second position, so that the dose feedback component on the metering dial bracket is retracted inwardly under the cooperation of the limiter to realize the rotation in the second direction and feedback the dose being corrected.

6. The adjustment feedback mechanism of the injection pen according to claim 5, characterized in that: A protrusion is provided on the outer wall of the dosage feedback component. When the set dosage needs to be corrected, the metering dial bracket rotates in the second direction, the limiter contacts the protrusion and squeezes the outer wall of the protrusion. When the limiter engages with the other side wall of the groove structure in the second position, the dosage feedback component on the metering dial bracket is retracted inwardly and the latch teeth of the first feedback mechanism and the ratchet teeth of the second feedback mechanism can still cooperate, thereby generating a hand feel in the second direction and feedback that the set dosage is being corrected.

7. The adjustment feedback mechanism of the injection pen according to claim 6, characterized in that: A first arc surface is provided between the tooth edge section of the latch tooth and the guide surface, and a second arc surface is provided between the abutting surface and the contact surface of the ratchet tooth. When the metering dial bracket rotates in the second direction, the first arc surface contacts the second arc surface, and the second arc surface squeezes the first arc surface to make the latch tooth contract inward, so as to correct the set dose. When the second arc surface does not squeeze the first arc surface, the tooth edge section of the latch tooth collides with one side of the ratchet tooth, and a sound is emitted to feedback that the set dose is being corrected.

8. The adjustment feedback mechanism of the injection pen according to claim 7, characterized in that: The outer wall of the elastic arm is provided with a protrusion. When the limiting member moves toward the injection end along with the screw sleeve, the limiting member presses the protrusion inwardly, so that the first feedback mechanism is completely separated from the second feedback mechanism, which facilitates the injection of the injection pen.

9. The adjustment feedback mechanism of the injection pen according to claim 8, characterized in that: A groove is provided at the connection between the dosage feedback component and the metering scale bracket to facilitate the inward retraction of the elastic arm.

10. The adjustment feedback mechanism of the injection pen according to claim 9, characterized in that: The free end of the elastic arm is also provided with a notch for avoiding the metering dial bracket when adjusting the dosage.

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