Pushing device for needleless injector

Abstract

The utility model discloses a pushing device for a needleless injector. The pushing device comprises a rotary driving part, a cam structure installed at the driving end of the rotary driving part and a cam shaft seat used for being connected with an injection push rod, and the cam structure is provided with a spiral moving wheel face and an axial extending guide face connected with the two ends of the spiral moving wheel face. In the power stroke, the cam shaft base abuts against the spiral moving wheel face, and the spiral moving wheel face is used for pushing the cam shaft base to move in the preset direction in the axial direction. In the reset stroke, when the cam shaft seat rotates to the position of the axial extending guide face, the cam shaft seat can freely move reversely in the preset direction relative to the axial direction of the cam structure. According to the invention, rotation is converted into linear driving, gradual axial movement can be realized at the spiral moving wheel surface, and axial quick release can be realized when the spiral moving wheel moves to the axial extending guide surface, so that the action requirements of other acting forces can be met. The pushing device can effectively solve the problem that axial driving of the injection push rod is inconvenient.

Description

Technical Field

[0001] The utility model relates to the technical field of injection equipment, and more specifically to a pushing device for a needle-free syringe. Background Art

[0002] Needle-free injection is a new injection technology that achieves the purpose of drug injection without needle puncture. It has the advantages of reducing the pain and fear of drug injection, reducing the risk of bacterial infection, avoiding accidents such as needle scratches and breakage, rapid drug absorption, no subcutaneous nodules after long-term use, and high injection efficiency.

[0003] The current pushing device generally uses a combination structure of a motor and a lead screw nut to drive the injection push rod, but when releasing it to restore the stroke, the operation is very inconvenient.

[0004] In summary, how to effectively solve the problem of inconvenient axial driving of the injection push rod is an issue that technicians in this field urgently need to solve. Utility Model Content

[0005] In view of this, an object of the present utility model is to provide a pushing device for a needle-free syringe, which can effectively solve the problem of inconvenient axial driving of the injection push rod.

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

[0007] A pushing device for a needle-free syringe comprises a rotating driving component, a cam structure installed on the driving end of the rotating driving component and a camshaft seat for connecting an injection push rod, the cam structure having a spiral wheel surface and axially extending guide surfaces connecting the two ends of the spiral wheel surface; in a power stroke, the camshaft seat abuts against the spiral wheel surface, and the spiral wheel surface is used to push the camshaft seat to move axially in a predetermined direction; in a reset stroke, when the camshaft seat rotates to the axially extending guide surface, the camshaft seat can freely move in the opposite direction to the predetermined direction relative to the cam structure axially.

[0008] In the above-mentioned pushing device, a cam structure and a matching camshaft seat are used to complete the conversion of rotation into linear drive, and gradual axial movement can be achieved at the spiral wheel surface, and when it moves to the axial extension guide surface, axial rapid release can be achieved to meet other force requirements. At this time, it returns to the starting point of the spiral wheel surface to continue the cycle operation. The pushing device can effectively solve the problem of inconvenient axial drive of the injection push rod.

[0009] Preferably, a power spring is further included, which is used to prevent the camshaft seat from moving backward during the power stroke; and to drive the camshaft seat to move axially forward relative to the cam structure during the reset stroke.

[0010] Preferably, the distribution angle of the spiral wheel surface is not greater than 320 degrees.

[0011] Preferably, the cam structure includes a shaft body, and a spiral protrusion and an axially extending protrusion are formed on the side of the shaft body. The driving side of the spiral protrusion has the spiral wheel surface, and one side of the axially extending protrusion is an axially extending guide surface. The terminal end of the spiral wheel surface and the corresponding end of the axially extending guide surface are connected by an arc, and the initial end of the spiral wheel surface and the axially extending guide surface are staggered in the circumferential direction.

[0012] Preferably, both ends of the shaft body are fitted on the base of the rotating drive component through bearings.

[0013] Preferably, the rear end of the shaft body is connected to the driving end via a pin, and the front end of the shaft body is provided with a screw hole for mounting a limit stop plate.

[0014] Preferably, the rotation driving component is a driving motor.

[0015] Preferably, one end of the injection push rod has an injection cavity, and the other end is sleeved with a power spring, and the camshaft seat is installed in the middle of the injection push rod.

[0016] Preferably, one end of the camshaft seat has a column portion for being inserted into the injection push rod in a transverse direction and fixed by screws along the insertion direction.

[0017] Preferably, the camshaft seat is provided with rollers so as to be able to rotate on the wheel surface of the cam structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the utility model 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 described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 A schematic cross-sectional structure diagram of a pushing device for a needle-free syringe provided in an embodiment of the utility model;

[0020] Figure 2 A structural schematic diagram of a cam structure provided in an embodiment of the utility model.

[0021] The following are marked in the accompanying drawings:

[0022] Injection push rod 1, cam structure 2, camshaft seat 3, rotation driving component 4, power spring 5, bearing 6;

[0023] Spiral protrusion 21, axially extending protrusion 22, spirally directed wheel surface 23, axially extending guide surface 24. DETAILED DESCRIPTION

[0024] The embodiment of the utility model discloses a pushing device for a needle-free syringe, which can effectively solve the problem of inconvenient axial driving of an injection push rod.

[0025] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0026] See also Figure 1-Figure 2 , Figure 1 A schematic cross-sectional structure diagram of a pushing device for a needle-free syringe provided in an embodiment of the utility model; Figure 2 A structural schematic diagram of a cam structure provided in an embodiment of the utility model.

[0027] In some embodiments, a pushing device for a needle-free syringe is provided, which mainly includes a rotation driving component 4 , a cam structure 2 and a cam shaft seat 3 .

[0028] The rotational drive component 4 refers to a mechanism that can output rotational drive at the driving end, such as a drive motor, a hydraulic motor, etc. Of course, the rotational drive component 4 can also include a linear drive mechanism, which is then connected to the driving end through a transmission mechanism through the linear drive mechanism. The transmission mechanism can convert the linear drive into a rotational drive transmission structure, wherein the transmission mechanism is such as a gear rack transmission mechanism.

[0029] The cam structure 2 is mounted on the driving end of the rotating driving component so as to be driven to rotate by the rotating driving component 4. The camshaft seat 3 is in contact with the wheel surface of the cam structure 2. Since the camshaft seat 3 is directly or indirectly connected to the injection push rod 1, and the injection push rod 1 is limited to be able to move only in the injection direction, a corresponding constraint is formed on the camshaft seat 3. During the rotation of the cam structure 2, the axially inclined wheel surface guides the camshaft seat 3 to move axially, so as to drive the injection push rod 1 to move axially in the corresponding direction, such as moving in the opposite direction of the injection direction, to complete the liquid extraction.

[0030] Specifically, the cam structure 2 has a spiral wheel surface 23 and an axially extending guide surface 24 connecting the two ends of the spiral wheel surface 23. The spiral wheel surface 23 abuts against the camshaft seat 3 to guide the camshaft seat 3 to move axially when the cam structure 2 rotates. As the cam structure 2 rotates, the camshaft seat 3 moves circumferentially relative to the cam structure 2 to the axially extending guide surface 24. At this time, the camshaft seat 3 cannot be supported by the cam structure 2 in the axial direction, so that the camshaft seat 3 moves in the axial direction in the opposite direction and can move to the spiral wheel surface 23 again. It should be noted that the direction of the axially extending guide surface 24 can be completely consistent with the axial direction and can be slightly tilted.

[0031] Specifically, in the power stroke, the camshaft seat 3 abuts against the spiral wheel surface 23, and the spiral wheel surface 23 is used to push the camshaft seat 3 to move axially in a predetermined direction; in the reset stroke, when the camshaft seat 3 rotates to the axial extension guide surface 24, the camshaft seat 3 can freely move in the opposite direction of the predetermined direction relative to the cam structure 2 to move to the initial section of the spiral wheel surface 23. The predetermined direction is taken as an example of the reverse direction of the injection direction. When the cam structure 2 rotates to the initial end of the camshaft seat 3 abutting against the spiral wheel surface 23, it continues to rotate and enters the power stroke. As the cam structure 2 continues to rotate, the camshaft seat 3 moves circumferentially relative to the cam structure 2 to drive the camshaft seat 3 to move in the opposite direction of the injection direction to complete the liquid extraction. As the cam structure 2 continues to rotate until the end of the spiral wheel surface 23 abuts against the camshaft seat 3, it enters the end of the power stroke, that is, the liquid extraction is completed. The cam structure 2 continues to rotate, and the camshaft seat 3 moves to the axially extending guide surface 24. Under the action of other forces, the camshaft seat 3 is no longer constrained by the injection direction, that is, it can move along the axially extending guide surface 24 and along the injection direction to complete the injection. At this time, the reset stroke is completed, and correspondingly, the camshaft seat 3 can move to the cam structure 2 again.

[0032] In the above-mentioned pushing device, the cam structure 2 and the matching camshaft seat 3 are used to complete the conversion of rotation into linear drive, and can realize gradual axial movement at the spiral wheel surface 23, and can realize axial rapid release when moving to the axial extension guide surface 24 to meet other force requirements, and at this time, it returns to the starting point of the spiral wheel surface 23 to continue the cycle operation. The pushing device can effectively solve the problem of inconvenient axial drive of the injection push rod 1.

[0033] In some embodiments, it is preferred that a power spring 5 is also included here, which is used to prevent the camshaft seat 3 from moving backward during the power stroke; and to drive the camshaft seat 3 to move axially forward relative to the cam structure 2 during the reset stroke. That is, the power spring 5 stores energy during the power stroke, and during the reset stroke, because the camshaft seat 3 moves to the axial extension guide surface 24, the axial force is released, so that the power spring 5 can release elastic energy to push the camshaft seat 3 to move in the reverse direction along the predetermined direction. It should be noted that the forward direction is the injection direction, that is, the predetermined direction mentioned above; correspondingly, the backward direction is the reverse direction of the injection direction.

[0034] In some embodiments, in order to allow a buffer period for the transition between the spiral wheel surface 23 and the axially extending guide surface 24, it is preferred that the distribution angle of the spiral wheel surface 23 is not greater than 320 degrees.

[0035] Specifically, a transverse guide surface can be used to transition between the initial end of the spiral wheel surface 23 and the terminal end of the axially extending guide surface 24 and / or between the terminal end of the spiral wheel surface 23 and the initial end of the axially extending guide surface 24, wherein the transverse guide surface is perpendicular to the axial direction so as to limit the camshaft seat 3 only in the axial direction during relative rotation, and will not move axially during the circumferential movement of the transverse guide surface.

[0036] In some embodiments, specifically, the cam structure 2 may include a shaft body, wherein a spiral protrusion 21 and an axially extending protrusion 22 are formed on the side of the shaft body, the driving side of the spiral protrusion 21 has the above-mentioned spiral wheel surface 23, and one side of the above-mentioned axially extending protrusion 22 is an axially extending guide surface 24, the terminal end of the spiral wheel surface 23 and the corresponding end of the axially extending guide surface 24 are connected by a circular arc, and the initial end of the spiral wheel surface 23 and the axially extending guide surface 24 are staggered in the circumferential direction. Taking the predetermined direction as the reverse direction of the injection direction as an example, at this time, the rear end of the spiral wheel surface 23 and the corresponding end of the rear end of the axially extending guide surface 24 are connected by a circular arc, and the front end of the spiral protrusion 21 is set with a sharp angle to better guide the camshaft seat 3. It should be noted that at the above-mentioned staggered part, the injection is completed at this time, and the power spring 5 completes the corresponding release stroke. At this time, the position of the camshaft seat 3 can be limited by the lateral guide surface on the camshaft seat 3, or it can be limited because the position of the injection push rod 1 is limited.

[0037] In some embodiments, for better initial shaft rotation, it is preferred that both ends of the shaft are matched to the base of the rotation drive component 4 through bearings 6. Taking the injection direction forward as an example, it is preferred that the rear end of the shaft is connected to the drive end through a pin, and a screw hole is provided at the front end of the shaft to install a limit stop plate to limit the axial position of the corresponding side bearing 6. The rotation drive component 4 is a drive motor.

[0038] In some embodiments, the injection push rod 1 may have an injection cavity at one end and a power spring 5 at the other end, and the camshaft seat 3 may be installed in the middle of the injection push rod 1. The camshaft seat 3 may be staggered to make the overall structure more compact. Of course, the camshaft seat 3 may also be installed at the rear end of the injection push rod 1.

[0039] In some embodiments, in order to facilitate the lateral parallel arrangement, it is preferred that one end of the camshaft seat 3 has a column portion to be inserted into the injection push rod 1 in the lateral direction and fixed by screws along the insertion direction.

[0040] In some embodiments, in order to facilitate the movement of the camshaft seat 3 on the wheel surface of the cam structure 2, it is preferred that the camshaft seat 3 has rollers so as to be able to rotate on the wheel surface of the cam structure 2.

[0041] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0042] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A pushing device for a needle-free syringe, It is characterized in that It includes a rotating drive component, a cam structure installed on the driving end of the rotating drive component and a camshaft seat for connecting an injection push rod, the cam structure has a spiral wheel surface and axially extending guide surfaces connecting the two ends of the spiral wheel surface; in the power stroke, the camshaft seat is against the spiral wheel surface, and the spiral wheel surface is used to push the camshaft seat to move axially in a predetermined direction; in the reset stroke, when the camshaft seat rotates to the axially extending guide surface, the camshaft seat can freely move in the opposite direction to the predetermined direction relative to the cam structure.

2. The pushing device according to claim 1, It is characterized in that It also includes a power spring, which is used to prevent the camshaft seat from moving backward during the power stroke; and to drive the camshaft seat to move axially forward relative to the cam structure during the reset stroke.

3. The pushing device according to claim 2, It is characterized in that The distribution angle of the spiral wheel surface is no greater than 320 degrees.

4. The pushing device according to claim 2, It is characterized in that The cam structure includes a shaft body, a spiral protrusion and an axially extending protrusion are formed on the side of the shaft body, the driving side of the spiral protrusion has the spiral wheel surface, one side of the axially extending protrusion is an axially extending guide surface, the terminal end of the spiral wheel surface and the corresponding end of the axially extending guide surface are connected by an arc, and the initial end of the spiral wheel surface and the axially extending guide surface are staggered in the circumferential direction.

5. The pushing device according to claim 4, It is characterized in that Both ends of the shaft body are matched with the base of the rotating driving component through bearings.

6. The pushing device according to claim 5, It is characterized in that The rear end of the shaft body is connected to the driving end through a pin, and the front end of the shaft body is provided with a screw hole for installing a limit stop plate.

7. The pushing device according to claim 6, It is characterized in that The rotation driving component is a driving motor.

8. The pushing device according to any one of claims 2 to 7, It is characterized in that One end of the injection push rod is provided with an injection cavity, and the other end is sleeved with a power spring, and the camshaft seat is installed at the middle part of the injection push rod.

9. The pushing device according to claim 8, It is characterized in that One end of the camshaft seat has a column portion for being inserted into the injection push rod in a transverse direction and fixed by screws along the inserting direction.

10. The pushing device according to claim 9, It is characterized in that The camshaft seat is provided with rollers so as to be able to rotate on the wheel surface of the cam structure.

Images