CN211357182U

CN211357182U - Medicine injector

Info

Publication number: CN211357182U
Application number: CN201921950031.8U
Authority: CN
Inventors: 刘靖宇; 蔡传进; 王涛; 李志臻; 李军; 王小虎
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-11-12
Filing date: 2019-11-12
Publication date: 2020-08-28
Anticipated expiration: 2029-11-12

Abstract

The utility model provides a medicine injector comprises a shell and a pushing assembly, a medicine placing space is arranged in the shell, a placing inlet is arranged at the first end of the extension of the medicine placing space, the pushing assembly comprises a lead screw, a first pushing piece and a second pushing piece, the lead screw is provided with a first external thread, the first pushing piece is provided with a first internal thread, the lead screw is arranged in the medicine placing space along the axial direction, the first pushing piece is sleeved outside the lead screw, and the first external thread is matched with the first internal thread; the second pushing piece is provided with a pushing surface; the second pushing piece is provided with a second internal thread, and the first pushing piece is provided with a second external thread; the second pushing piece is sleeved outside the first pushing piece, and the second external thread is matched with the second internal thread. The two sections of telescopic pushing assemblies reduce the axial size on the premise of keeping the pushing of the limit distance unchanged, and the medicine injection has a smaller volume on the premise of ensuring the medicine dosage.

Description

Medicine injector

Technical Field

The utility model relates to the technical field of medical equipment, concretely relates to medicine injector.

Background

The existing medicine injector for insulin injection comprises a shell, a power supply, a motor, a transmission gear set and a pushing assembly, wherein the power supply, the motor, the transmission gear set and the pushing assembly are arranged in the shell; the shell is internally provided with a medicine placing space, the medicine placing space extends into a long shape along the axial direction, one end of the medicine placing space is provided with a placing inlet, and the screw rod and the pushing piece are arranged in the medicine placing space.

The drug container of insulin is a pump body, a soft rubber plug is arranged at the first end of the drug container, and a piston body is arranged at the second end of the drug container; after the medicine container is placed in the medicine placing space and the end cover with the needle body is covered, the pushing piece faces the piston body, the needle body pierces the soft rubber plug and is communicated into the medicine container, at the moment, after a user presses the injection button to give a motor starting signal, the screw rod rotates, the pushing piece pushes the piston body to move, and liquid enters the infusion tube through the needle body.

The existing medicine injector has the problems that the stroke amount of the pushing piece is only determined by the length of the screw rod, and the pushing piece needs to push the piston body to the limit position, so that the length of the screw rod is longer, the volume of a needle body of the medicine injector is larger, or the loading dose of medicines is reduced for keeping the small volume of the medicine injector.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a guarantee medicine dosage and less medicine syringe of volume.

The utility model provides a medicine injector comprises a shell and a pushing assembly, a medicine placing space is arranged in the shell, a placing inlet is arranged on a first end of the medicine placing space extending in the axial direction, the pushing assembly comprises a lead screw and a first pushing piece, a first external thread is arranged on the periphery of the lead screw, a first internal thread is arranged on the inner periphery of the first pushing piece, the lead screw is rotatably arranged in the medicine placing space along the axial direction, the first pushing piece is sleeved outside the lead screw, and the first external thread is matched with the first internal thread; the pushing assembly also comprises a second pushing piece, and the axial end part of the second pushing piece is provided with a pushing surface; a second internal thread is arranged on the inner periphery of the second pushing piece, and a second external thread is arranged on the outer periphery of the first pushing piece; the second pushing piece is sleeved outside the first pushing piece, the second external thread is matched with the second internal thread, and the pushing surface faces the placing inlet.

According to the above technical scheme, the utility model provides a two sections flexible promotion subassemblies, first impeller can be for the translation of lead screw, and the second impeller can be for the translation of first impeller, under the unchangeable prerequisite of limit distance promotion, and the three is less at the ascending size of axial when the shrink state, and consequently the medicine is placed the space and can be set up to littleer axial dimension, makes the medicine injection have a smaller volume under the prerequisite of guaranteeing the medicine dose.

The pushing assembly further comprises a rotation stopping sleeve, the rotation stopping sleeve penetrates through the pushing assembly along the axial direction, and the rotation stopping sleeve is sleeved outside the second pushing piece; the inner peripheral surface of the medicine placing space is provided with a guide convex strip extending along the axial direction, the outer periphery of the rotation stopping sleeve is provided with a guide concave position, and the guide convex strip is matched with the guide concave position along the axial direction; the inner periphery of the rotation stopping sleeve is provided with a guide groove extending along the axial direction, the outer periphery of the second pushing piece is provided with a guide bulge, and the guide bulge and the guide groove are in sliding fit along the axial direction.

It can be seen from above that, the rotation stopping sleeve is connected between the inner peripheral surface of the medicine placing space and the pushing assembly, and the rotation stopping sleeve can effectively keep the rotation stopping matching among the first pushing piece, the second pushing piece, the rotation stopping sleeve and the shell, so that the stability of axial translation of the pushing assembly is kept, and the injection precision is improved.

Further, in the axial direction, the medicine placing space has an extended second end opposite to the extended first end; in the axial direction, the guide convex strip extends between the extended second end and the first position; in the axial direction, the rotation stopping sleeve can move and extend between the second end and a second position, the second position is a position where the guide concave position is close to the extending first end relative to the first position, and the guide concave position is separated from the guide convex strip.

It can be seen from the above that, after the first pushing piece and the second pushing piece reach the extreme positions, when the second pushing piece drives the rotation stopping sleeve to move to a certain position, the guide concave position is separated from the guide convex strip, at this time, the rotation stopping matching relationship between the rotation stopping sleeve and the shell is released, and the first pushing piece and the second pushing piece rotate along with the screw rod, so that the pushing structure and the medicine container are prevented from being damaged.

The further scheme is that a first guide inclined plane is arranged on the extending end part of the guide convex strip at the first position, and the first guide inclined plane extends towards the first end and faces towards the circumferential direction of the medicine placing space.

Therefore, the arrangement increases the probability of the rotation stopping sleeve to be separated from the guide boss, and further ensures that the pushing structure and the medicine container are not damaged.

The further proposal is that the guide groove penetrates between the inner side and the outer side of the rotation stopping sleeve.

From above, this sets up the processing degree of difficulty that makes the direction recess and reduces.

The further scheme is that a first blocking surface is arranged at the extending tail end close to the extending first end in the guide groove, and the first blocking surface blocks the guide protrusion axially.

Therefore, the arrangement ensures the matching relationship of the rotation stopping sleeve and the second pushing piece in the axial direction, and the structure is more compact.

The further proposal is that a second stop surface is arranged at the extending tail end far away from the extending first end in the guide groove; the guide bulge is provided with a second guide inclined plane which is back to the axis of the guide bulge and faces the second stop surface.

Therefore, the second pushing piece and the rotation stopping sleeve can be conveniently assembled, and the production efficiency is improved.

The further scheme is that a blocking ring formed by protruding from the outer peripheral surface of the rotation stopping sleeve to the outer peripheral surface is arranged at the axial end part of the rotation stopping sleeve far away from the first extending end, and the guide concave position is arranged on the blocking ring.

The first pushing piece is provided with a first peripheral wall, the inner peripheral surface of the first peripheral wall is provided with a shoulder at a position far away from the extending first end, and the first internal thread is arranged on the inner periphery of the shoulder; the screw rod is detachably provided with a blocking piece at the axial end part facing the first extending end, and the blocking piece limits the shoulder in the axial direction.

As can be seen, this arrangement effectively prevents the second pushing member from being disengaged from the first pushing member.

The medicine injector further comprises a rotation driving unit and a transmission gear set, wherein the rotation driving unit and the transmission gear set are arranged in the shell; the transmission gear set comprises an input gear and an output gear, the input gear is connected to the rotation output end of the rotation driving unit, and the screw rod is coaxially connected with the output gear.

Drawings

Fig. 1 is a sectional view of an embodiment of a medical injector according to the present invention.

Fig. 2 is an exploded view of the second housing, the transmission gear set and the lead screw according to the embodiment of the medical injector of the present invention.

Fig. 3 is a partially enlarged view of a portion a in fig. 1.

Figure 4 is a cross-sectional view of the first housing in an embodiment of the medical injector of the present invention.

Fig. 5 is a diagram of a first operating state of a pushing assembly in an embodiment of a medical injector according to the present invention.

Fig. 6 is a diagram of a second operating state of the pushing assembly in the embodiment of the medical injector of the present invention.

Detailed Description

Referring to fig. 1, fig. 1 is a sectional view of an embodiment of a medical injector according to the present invention. The utility model provides a medicine injector, including shell 1, end cover 2, motor 3, drive gear group 4 and promotion subassembly 5, shell 1 is including dismantling continuous first casing 11 and second casing 12 each other, has the medicine in the first casing 11 and places space 101, has transmission space 102 in the second casing 12, has on the second casing 12 and keeps off wall 121, and after first casing 11 and second casing 12 interconnect, keep off wall 121 and block between transmission space 102 and medicine place space 101.

A placing inlet 119 is arranged on the first end 101a of the medicine placing space 101 extending in the axial direction, and the end cover 2 with the needle body 21 is covered on the placing inlet 119; the axially extending second end 101b of the medication placing space 101 is where the stop wall 121 is located. The motor 3, the transmission gear set 4 and the pushing assembly 5 are all arranged in the housing 1, the transmission gear set 4 is arranged in the transmission space 102, and the pushing assembly 5 is arranged in the medicine placing space 101.

Referring to fig. 2 and 3, fig. 2 is an exploded view of a second housing, a transmission gear set and a lead screw according to an embodiment of the medical injector of the present invention, and fig. 3 is a partially enlarged view of a portion a in fig. 1. The transmission gear set 4 includes an input gear 41, an output gear 42, and a plurality of transmission gears connected between the input gear 41 and the output gear 42, and the input gear 41 is connected to an output shaft of the motor 3 as a rotation driving unit.

The output gear 42 comprises a first gear section 421, a second gear section 422 and a third gear section 423 which are sequentially connected along the axial direction, gear teeth are arranged on the third gear section 423, and the outer diameters of the first gear section 421, the second gear section 422 and the third gear section 423 are sequentially increased. The output gear 42 is provided with an insertion concave portion 424 on an axial end face of the first gear segment 421, and the insertion concave portion 424 is in a line shape on an axial projection. When the output gear 42 is mounted in the set position of the set transmission space 102, the axial direction of the output gear 42 is parallel to the axial direction of the medicine placing space 101, and the insertion recess 424 faces the blocking wall 121.

The blocking wall 121 is provided with a connecting through hole 122 communicated between the transmission space 102 and the medicine placing space 101, a step position 123 axially communicated with the connecting through hole 122 is formed on the blocking wall 121, a step surface 124 facing the output gear 42 is formed between the step position 123 and the connecting through hole 122, the first gear section 421 is positioned in the step position 123, the outer peripheral surface of the first gear section 421 is matched with the inner peripheral surface of the step position 123, and the second gear section 422 is in spacing fit with the blocking wall 121 in the axial direction. A space for receiving the shoulder portion 513 of the lead screw 51 is formed between the stepped surface 124 and the end surface of the first gear segment 421.

The pushing assembly 5 comprises a screw rod 51, the screw rod 51 is provided with a thread part 511, a rotating matching part 512, a shaft shoulder part 513 and an insertion bulge 514 which are sequentially arranged in the axial direction, the insertion bulge 514 bulges along the axial direction from the axial end surface of the shaft shoulder part 513, the insertion bulge 514 is in a shape like a Chinese character 'yi' in the axial projection, the inner peripheral outline of the insertion concave part 424 is matched with the outer peripheral outline of the insertion bulge 514, and the extending tail end of the insertion bulge 514 is provided with a guide inclined plane. An annular groove 510 is formed in the outer periphery of the rotation fitting portion 512, and a seal ring 515 is provided in the annular groove 510.

Before the transmission gear set 4 is installed in the transmission space 102, the screw rod 51 penetrates through the connecting through hole 122, the thread part 511 penetrates out of the medicine placing space 501, the rotating matching part 512 is located in the connecting through hole 122, the rotating matching part 512 is in rotating matching with the blocking wall 121, and the sealing ring 515 is arranged between the rotating matching part 512 and the inner circumferential surface of the connecting through hole 122; the shaft shoulder 513 is located in the step 123. After the output gear 42 is installed, the insertion protrusion 514 is inserted into the insertion recess 424, and the shoulder 513 is limited between the stepped surface 124 and the end surface of the first gear segment 421. When carrying out the installation that promotes subassembly 5 or using the medicine syringe, all can not lead to the swing because of the unstability of lead screw axial position, reduce the assembly degree of difficulty and improve the injection precision.

Referring to fig. 4, fig. 4 is a cross-sectional view of the first housing in an embodiment of the medical injector of the present invention. The inner circumferential surface 111 of the medicine containing space 101 is provided with a guide rib 112 extending in the axial direction, the guide rib 112 extends between the second end 101b and the first position 101c, a first guide inclined surface 113 is provided on an extending end portion of the guide rib 112 located at the first position 101c, and the first guide inclined surface 113 faces the first end 101a and faces the circumferential direction of the medicine containing space 101.

Referring to fig. 1, 4 and 5, fig. 5 is a structural diagram of a first working state of a pushing assembly in an embodiment of a medical injector according to the present invention. The pushing assembly 5 includes a screw 51, a first pushing member 52, a second pushing member 53, and a rotation stopping sleeve 54.

The first pusher 52 has a first peripheral wall 521, an inner peripheral surface of the first peripheral wall 521 is provided with a shoulder 522 away from the extended first end 101a, and an inner periphery of the shoulder 522 is provided with a first internal thread; a first external thread is arranged on the periphery of the threaded part 511, the first pushing piece 52 is sleeved outside the screw rod 51, and the first external thread is matched with the first internal thread; the stopper 59 is detachably attached to the threaded portion 511 at an axial end portion toward the extended first end 101a, the stopper 59 is a stopper bolt, and the stopper 59 limits the shoulder 522 in the axial direction.

The second pusher 53 has a pusher face 530 on an axial end thereof; the inner periphery of the second pushing piece 53 is provided with a second internal thread, and the outer periphery of the first pushing piece 52 is provided with a second external thread; the second pushing member 53 is sleeved outside the first pushing member 52, the second external thread is matched with the second internal thread, and the pushing surface 530 faces the placing inlet 119. The outer periphery of the second pusher 53 is provided with a pair of guide protrusions 531 at an end near the extended first end 101a, the guide protrusions 531 are provided with second guide inclined surfaces 531a, and the second guide inclined surfaces 531a face away from the axial center of the guide protrusions 531 and face the second blocking surfaces 542 b.

The rotation stopping sleeve 54 penetrates through the axial direction, a pair of guide concave positions 544 which are symmetrically arranged are arranged on the periphery of the rotation stopping sleeve 54, a pair of guide grooves 542 which extend along the axial direction and penetrate through the inner side and the outer side of the rotation stopping sleeve 54 are further arranged on the rotation stopping sleeve 54, and the arrangement directions of the guide concave positions 544 and the guide grooves 542 are different by 90 degrees; a first stop surface 542a is arranged in the guide groove 542 close to the extending tail end of the extending first end 101a, a stop ring 543 which is formed by protruding from the outer circumferential surface of the rotation stop sleeve 54 to the outer circumference is arranged at the axial end part of the rotation stop sleeve 54 far away from the extending first end 101a, a second stop surface 542b is arranged in the guide groove 542 far away from the extending tail end of the extending first end 101a, and the second stop surface 542b is the surface of the stop ring 543; the stop ring 543 is provided with a pair of guiding recesses 544 penetrating in the axial direction.

The rotation stopping sleeve 54 is sleeved outside the second pushing member 53, the guide protrusion 531 is in sliding fit with the guide groove 542 in the axial direction, the first blocking surface axially blocks the guide protrusion 531, and the guide recess 544 on the rotation stopping sleeve 54 is in sliding fit with the guide convex strip 112 on the inner circumferential surface 111 of the medicine placing space 101 in the axial direction.

After the motor 3 is started to enable the screw rod 51 to rotate, the first pushing piece 52 translates relative to the screw rod 51, the second pushing piece 53 can translate relative to the first pushing piece 52, and under the premise that the limit distance pushing is not changed, the size of the first pushing piece, the second pushing piece and the second pushing piece in the axial direction is smaller when the first pushing piece, the second pushing piece and the third pushing piece are in a shrinkage state, so that the medicine placing space 101 can be set to be smaller in axial size, and the medicine injection is enabled to have a smaller.

Referring to fig. 6, fig. 6 is a structural diagram of a second working state of the pushing assembly in the embodiment of the medical injector of the present invention. In the axial direction, the rotation preventing sleeve 54 is movable and extends between the second end 101b and a second position 101d, the second position 101d being a position where the guide recess 544 is close to the extended first end 101a relative to the first position 101c, and the guide recess 544 is separated from the guide rib 112. After the first pushing member 52 and the second pushing member 53 reach the extreme positions, when the second pushing member 53 drives the rotation stopping sleeve 54 to move to the second position 101d towards the extended first end 101a, the guide concave part 544 is separated from the guide convex strip 112, at this time, the rotation stopping matching relationship between the rotation stopping sleeve 54 and the housing 1 is released, and the first pushing member 53 and the second pushing member 52 rotate along with the screw rod 51, so that the pushing structure 5 and the medicine container are prevented from being damaged.

Finally, it should be emphasized that the above-described embodiments are merely preferred examples of the present invention, and are not intended to limit the invention, as those skilled in the art will appreciate that various changes and modifications may be made, and any and all modifications, equivalents, and improvements made, while remaining within the spirit and principles of the present invention, are intended to be included within the scope of the present invention.

Claims

1. The medicine injector comprises a shell and a pushing assembly, wherein a medicine placing space is arranged in the shell, a placing inlet is formed in the first end, extending in the axial direction, of the medicine placing space, the pushing assembly comprises a screw rod and a first pushing piece, a first external thread is arranged on the periphery of the screw rod, a first internal thread is arranged on the inner periphery of the first pushing piece, the screw rod is rotatably arranged in the medicine placing space along the axial direction, the first pushing piece is sleeved outside the screw rod, and the first external thread is matched with the first internal thread;

the method is characterized in that:

the pushing assembly further comprises a second pushing member, and the axial end part of the second pushing member is provided with a pushing surface;

a second internal thread is arranged on the inner periphery of the second pushing piece, and a second external thread is arranged on the outer periphery of the first pushing piece;

the second pushing piece is sleeved outside the first pushing piece, the second external thread is matched with the second internal thread, and the pushing face faces the placing inlet.

2. The drug injector of claim 1, wherein:

the pushing assembly further comprises a rotation stopping sleeve, the rotation stopping sleeve penetrates through the axial direction, and the rotation stopping sleeve is sleeved outside the second pushing piece;

the inner circumferential surface of the medicine placing space is provided with a guide convex strip extending along the axial direction, the periphery of the rotation stopping sleeve is provided with a guide concave position, and the guide convex strip is matched with the guide concave position along the axial direction;

the inner periphery of the rotation stopping sleeve is provided with a guide groove extending along the axial direction, the outer periphery of the second pushing piece is provided with a guide protrusion, and the guide protrusion and the guide groove are in sliding fit along the axial direction.

3. The drug injector of claim 2, wherein:

in the axial direction, the drug placement space has an extended second end opposite the extended first end;

in the axial direction, the guide rib extends between the extended second end and a first position;

in the axial direction, the rotation stopping sleeve is movable between the second extending end and a second position, the second position is a position where the guide concave position is close to the first extending end relative to the first position, and the guide concave position is separated from the guide convex strip.

4. The drug injector of claim 3, wherein:

the last position of direction sand grip is provided with first direction inclined plane on the extension tip of first position, first direction inclined plane orientation extend first end and orientation the circumference in space is placed to the medicine.

5. The drug injector of claim 2, wherein:

the guide groove penetrates between the inner side and the outer side of the rotation stopping sleeve.

6. The drug injector of claim 2, wherein:

the guide groove is internally provided with a first blocking surface at the extending tail end close to the extending first end, and the first blocking surface blocks the guide protrusion axially.

7. The drug injector of claim 2, wherein:

a second blocking surface is arranged at the extending tail end, far away from the extending first end, of the guide groove;

the guide protrusion is provided with a second guide inclined plane, and the second guide inclined plane is back to the axis of the guide protrusion and faces the second blocking surface.

8. The drug injector of claim 2, wherein:

the axial end part of the rotation stopping sleeve far away from the first extending end is provided with a retaining ring formed by protruding from the outer peripheral surface of the rotation stopping sleeve to the outer peripheral surface, and the guide concave position is arranged on the retaining ring.

9. The drug injector of any of claims 1 to 8, wherein:

the first pushing piece is provided with a first peripheral wall, the inner peripheral surface of the first peripheral wall is provided with a shoulder at the position far away from the extending first end, and the first internal thread is arranged on the inner periphery of the shoulder;

a stopper is detachably mounted to the screw rod at an axial end portion facing the extended first end, and the stopper limits the shoulder from the axial direction.

10. The drug injector of any of claims 1 to 8, wherein:

the drug injector further comprises a rotation driving unit and a transmission gear set, wherein the rotation driving unit and the transmission gear set are arranged in the shell;

the transmission gear set comprises an input gear and an output gear, the input gear is connected to the rotation output end of the rotation driving unit, and the screw rod is coaxially connected with the output gear.