Pipette head withdrawing mechanism of pipettor and pipettor

Abstract

The invention belongs to the technical field of pipettors, and relates to a pipette tip withdrawing mechanism and a pipettor, the pipette tip withdrawing mechanism comprises: a needle withdrawing sleeve sleeving a pipette tip rod of a pipette body, the needle withdrawing sleeve sliding on the pipette tip rod; the swing part is rotationally connected to the base of the pipettor body; the middle part of the swinging part is rotationally connected to a base of the pipettor body; the two ends of the swing part form a lever structure with the middle as a fulcrum. The end, close to the needle withdrawing sleeve, of the swing piece is matched with the top of the needle withdrawing sleeve. The execution part is connected to the base of the pipettor body; the output end of the execution part is connected with the other end of the swing part, and the execution part drives the end, away from the needle withdrawing sleeve, of the swing part to press down the needle withdrawing sleeve. After the structure is adopted, the pipettor has the beneficial effects that the gun retreating action of the gun head is carried out by adopting the lever principle, and the needle retreating space design of a needle retreating plate is omitted, so that the integrity of the pipettor is better.

Description

Technical Field

[0001] The invention belongs to the technical field of pipettes, and in particular relates to a pipette head retracting mechanism and a pipette. Background Art

[0002] In biochemical experiments and clinical tests, the pipette is one of the core components of the entire experimental process. At present, the pipette tip is removed by basically using the cooperation of a needle withdrawal plate and a cylinder. In this way, a space for the needle withdrawal action required by the needle withdrawal plate needs to be designed inside the pipette device, which results in a poor overall layout of the device and a large volume, resulting in poor coordination accuracy between the liquid aspiration and discharge units, thereby affecting the liquid aspiration and discharge accuracy of the pipette device. Therefore, it is necessary to make improvements. Summary of the invention

[0003] In order to solve the above problems in the prior art, the present invention provides a pipette tip retracting mechanism and a pipette, which have a simple structure and are independent of a liquid aspirating and discharging unit, and do not affect the coordination accuracy of liquid aspirating and discharging.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] As one aspect of the present invention, a pipette tip retracting mechanism is provided, which comprises: a needle retracting sleeve sleeved on a tip rod of a pipette body, the needle retracting sleeve sliding on the tip rod;

[0006] A swinging member, the swinging member is rotatably connected to the base of the pipette body; the middle part of the swinging member is rotatably connected to the base of the pipette body; the two ends of the swinging member form a lever structure with the middle part as a fulcrum; the end of the swinging member close to the needle withdrawal sleeve is connected to the top of the needle withdrawal sleeve;

[0007] The actuator is connected to the base of the pipette body; the output end of the actuator is connected to the other end of the swing member, and the actuator drives the end of the swing member away from the needle withdrawal sleeve to press the needle withdrawal sleeve downward, or the actuator drives the needle withdrawal sleeve to slide upward along the gun head rod through the swing member.

[0008] As a second aspect of the present invention, a pipette tip retracting mechanism is provided, which comprises: a needle retracting sleeve sleeved on a tip rod of a pipette body, the needle retracting sleeve sliding on the tip rod;

[0009] A swinging member, wherein the swinging member is rotatably connected to the base of the pipette body; the middle part of the swinging member is rotatably connected to the base of the pipette body; the two ends of the swinging member form a lever structure with the middle part as a fulcrum; there is a gap between the end of the swinging member close to the needle withdrawal sleeve and the top of the needle withdrawal sleeve;

[0010] The actuator is connected to the base of the pipette body; the output end of the actuator is connected to the other end of the swinging member, and the actuator drives the end of the swinging member away from the needle withdrawal sleeve to press down the needle withdrawal sleeve, or the actuator is tilted relative to the needle withdrawal sleeve through the end of the swinging member away from the needle withdrawal sleeve;

[0011] The sleeve connecting part includes a guide piece, and the guide piece is movably arranged on the base of the pipette body; the lower end of the guide piece is detachably connected to the needle withdrawal sleeve.

[0012] Optionally, a protrusion is formed on the needle withdrawal sleeve; there is a gap between the end of the swinging member close to the needle withdrawal sleeve and the top of the protrusion; the actuator drives the end of the swinging member away from the needle withdrawal sleeve to press down the protrusion, or the actuator is tilted relative to the protrusion through the end of the swinging member away from the needle withdrawal sleeve.

[0013] Optionally, one end of the guide member is detachably connected to a protrusion on the needle withdrawal sleeve; a first mounting hole is provided on the base of the pipette body, and the guide member is movably inserted into the first mounting hole; an elastic member is provided on the guide member, and the elastic member is located in the first mounting hole.

[0014] Optionally, an induction switch is further included, wherein the induction switch is connected to the base of the pipette body, and the guide member is used in conjunction with the induction switch.

[0015] Optionally, it also includes a connecting part, and the actuator is connected to the swinging member through the connecting part; the connecting part includes a connecting block slidably connected to the swinging member, and the output end of the actuator is connected to the connecting block; the connecting block is connected to a connecting rod, and the connecting rod is connected to the swinging connecting part or the swinging sliding part on the swinging member.

[0016] It also includes a connecting part, through which the executing part is connected to the swinging member; the connecting part includes a connecting block movably connected to the swinging member, and the output end of the executing part is connected to the connecting block; the connecting block is connected to a connecting rod, and the connecting rod is movably connected to the swinging movable part on the swinging member.

[0017] Optionally, it further comprises an auxiliary action piece, the auxiliary action piece is connected to a guide rod, when the auxiliary action piece is rotatably connected to one end of the swinging piece, a penetration hole for the guide rod to movably penetrate is provided on the base or the pipette body, and the guide rod is movably penetrated in the penetration hole; the size of the penetration hole is larger than the diameter of the guide rod, and the guide rod can move in the penetration hole under the action of an external force;

[0018] Or when the auxiliary action piece is slidably connected to one end of the swing piece, the auxiliary action piece is connected to a guide rod, and the base or the pipette body is provided with a penetration hole for the guide rod to movably penetrate, and the guide rod is movably penetrated in the penetration hole.

[0019] Optionally, a wiring channel is also provided on the needle withdrawal sleeve.

[0020] Optionally, the elastic member is passed through the guide member, and under normal conditions, the elastic member causes the needle withdrawal sleeve to be located at a preset height on the gun head rod.

[0021] Optionally, it further comprises a sensing unit, which is connected to the base or the pipette body; the guide rod is used in conjunction with the sensing unit.

[0022] As another aspect of the present invention, a pipette is provided, comprising the pipette tip retracting mechanism as described above.

[0023] The beneficial effects of the pipette tip retracting mechanism and the pipette of the present invention are specifically embodied in: 1. The lever principle is used to perform the gun tip retracting action, thereby avoiding the increase of the pipette cavity space and the design of the needle retracting plate, thereby improving the pipetting accuracy and the rationality of the overall layout space;

[0024] 2. The elastic member allows the needle withdrawal sleeve to be at a preset height on the gun head rod, so that the guide part for the gun head on the gun head rod is not completely blocked by the needle withdrawal sleeve, in order to ensure that the connection part between the gun head rod and the gun head is partially exposed, which is convenient for the installation of the gun head;

[0025] 3. The design of the routing channel can prevent the capacitor routing from being exposed;

[0026] 4. The design of auxiliary action parts shortens the power stroke of the actuator and saves costs;

[0027] 5. The design of sleeve connection part and induction switch is adopted to sense whether the gun head is installed in place, and also to ensure the return of the needle withdrawal sleeve to ensure that the gun head can be inserted into the gun head rod. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The drawings in the specification, which constitute a part of this application, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0029] Figure 1 It is a structural stereogram of a pipette with a gun head retracting mechanism according to Example 1 of the present invention;

[0030] Figure 2 It is a structural side view of a pipette with a gun tip retracting mechanism according to embodiment 1 of the present invention;

[0031] Figure 3 It is a structural stereogram of a pipette with a gun head retracting mechanism according to embodiment 2 of the present invention;

[0032] Figure 4 It is a structural side view of a pipette with a gun head retracting mechanism according to embodiment 2 of the present invention;

[0033] Figure 5 It is a structural stereogram of the gun head retracting mechanism of embodiment 2 of the present invention;

[0034] Figure 6 It is a bottom view of the structure of the gun head retracting mechanism of embodiment 2 of the present invention;

[0035] Figure 7 It is a structural cross-sectional view of a gun head retracting mechanism according to Embodiment 2 of the present invention;

[0036] Figure 8 It is a structural schematic diagram of the connecting portion of the present invention;

[0037] Fig. 9 It is a structural schematic diagram of the auxiliary action member of the present invention;

[0038] Fig.10 It is a front view of the installation state of the auxiliary action member and the guide rod of the present invention;

[0039] Fig.11 It is a rear view of the auxiliary action member and the guide rod of the present invention in the installed state;

[0040] Fig.12 It is a structural exploded view of the auxiliary action member and the guide rod of the present invention;

[0041] Fig.13 It is a cross-sectional view of the auxiliary action member and the guide rod of the present invention in the installation state;

[0042] Description of reference numerals: 1-gun tip rod; 11-pipette body; 12-first mounting hole; 13-base; 131-through hole;

[0043] 2-needle withdrawal sleeve; 21-bump;

[0044] 31- guide part;

[0045] 4-swinging member; 41-swinging movable part;

[0046] 5-Executive Department;

[0047] 6-sleeve connecting part; 61-guide member; 62-elastic member; 63-inductive switch;

[0048] 7-connecting part; 71-connecting block; 72-connecting rod;

[0049] 8- auxiliary action member; 81- second mounting hole;

[0050] 9-Guide rod. DETAILED DESCRIPTION

[0051] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below through specific implementation modes in conjunction with the accompanying drawings.

[0052] Example 1

[0053] A pipette tip retracting mechanism of an embodiment of the present application is as follows: Figure 1-Figure 2 As shown, it comprises: a needle withdrawal sleeve 2 sleeved on the gun head rod 1 of the pipette body 11, and the needle withdrawal sleeve 2 slides on the gun head rod 1; it should be noted that the pipette body 11 comprises a base 13, and the base 13 is connected with a gun head rod 1, one end of the gun head rod 1 is connected with a gun head, and the other end of the gun head rod 1 is connected to a pipette gun, and one end of the gun head rod 1 is detachably connected with a gun head for sucking and releasing liquid; a channel is formed in the gun head rod 1; the other end of the gun head rod 1 is connected to the pipette gun, and the structure and working principle of this pipette body 11 are all prior art and will not be repeated; a convex block 21 is formed on the needle withdrawal sleeve 2;

[0054] A swinging member 4, wherein the swinging member 4 is rotatably connected to the base 13 of the pipette body 11; as an example, the middle part of the swinging member 4 is rotatably connected to the base 13 of the pipette body 11; the two ends of the swinging member 4 form a lever structure with the middle part as a fulcrum; the end of the swinging member 4 close to the needle withdrawal sleeve 2 is connected to the top of the needle withdrawal sleeve 2, and it should be noted that the swinging member 4 and the top of the needle withdrawal sleeve 2 are movably connected, for example: a connecting hole is provided on the swinging member 4, and a connecting pin is formed on the top of the needle withdrawal sleeve 2, and the connecting pin is movably connected to the connecting hole; or it is movably connected to the connecting hole through a connecting rod;

[0055] The actuator 5 is connected to the base 13 of the pipette body 11; the output end of the actuator 5 is connected to the other end of the swing member 4; as an example, the actuator 5 is a motor, which is a prior art and will not be described in detail; when the actuator 5 works, it drives the other end of the swing member 4 to move upward or downward with the middle of the swing member 4 as a fulcrum, so that one end of the swing member 4 is driven to press down the protrusion 21, and drives the end of the needle withdrawal sleeve 2 to withdraw the gun head on the gun head rod 1; or the actuator 5 drives the needle withdrawal sleeve 2 to slide upward along the gun head rod 1 through the swing member 4, so that the needle withdrawal sleeve 2 is away from the gun head, which is convenient for the installation of the gun head and the gun head rod 1.

[0056] As a further illustration, in this embodiment, Figure 1 , Figure 2 and Fig. 9As shown, it also includes an auxiliary action piece 8, which is rotatably connected to one end of the swinging piece 4. The auxiliary action piece 8 is provided with a second mounting hole 81, and the auxiliary action piece 8 is rotatably connected to the swinging piece 4 through the cooperation of the second mounting hole 81 and the pin shaft; the bottom of the auxiliary action piece 8 is connected to the top of the protrusion 21 on the needle withdrawal sleeve 2, and the swinging piece 4 can achieve a larger action expansion space for the needle withdrawal sleeve 2 through the auxiliary action piece 8, which is convenient for the layout of the overall space; the execution part 5 drives the end of the swinging piece 4 away from the needle withdrawal sleeve 2 to press down the protrusion 21, so that the needle withdrawal sleeve 2 withdraws the gun head, or the execution part 5 drives the needle withdrawal sleeve 2 to slide upward along the gun head rod 1 through the swinging piece 4, so that the needle withdrawal sleeve 2 is away from the gun head, which is convenient for the installation of the gun head and the gun head rod 1.

[0057] In this embodiment, if Figure 1 and Figure 8 As shown, it also includes a connecting part 7, and the actuator 5 is connected to the swing member 4 through the connecting part 7, so that the connection between the two is more convenient; the connecting part 7 includes a connecting block 71 slidably connected to the swing member 4. It should be noted that the connecting block 71 is connected to the swing member 4 in a sliding manner, such as a slide groove; the output end of the actuator 5 is connected to the connecting block 71, and the output end of the actuator 5 is threadedly connected to the connecting block 71, and a connecting rod 72 is connected to the connecting block 71, and the connecting rod 72 is movably connected to the swing movable part 41 on the swing member 4.

[0058] As an example, the swinging movable part 41 is a slide groove arranged in the swinging member 4. When the swinging movable part 41 is a slide groove, the connecting rod 72 and the slide groove form a sliding connection; in this embodiment, the actuator 5 is a forward and reverse motor, and the output end of the actuator 5 is threadedly connected to the connecting block 71. Through the forward or reverse rotation of the actuator 5, the connecting rod 72 is driven to move upward or downward on the swinging movable part 41 on the swinging member 4; or when the actuator 5 is a lifting motor or a lifting cylinder, the output end of the actuator 5 is detachably connected to the connecting block 71, and through the forward or reverse rotation of the actuator 5, the connecting rod 72 is driven to move upward or downward on the swinging movable part 41 on the swinging member 4.

[0059] In this embodiment, if Figure 1 and Figure 9-13As shown, the auxiliary action piece 8 is connected to a guide rod 9. When the auxiliary action piece 8 is rotatably connected to one end of the swinging piece 4, a penetration hole 131 for the guide rod 9 to be movably penetrated is provided on the base 13 or the pipette body 11. The guide rod 9 is movably penetrated in the penetration hole 131. The size of the penetration hole 131 is larger than the diameter of the guide rod 9 and is used for guiding the auxiliary action piece 8 to realize the action between the auxiliary action piece 8 and the needle withdrawal sleeve 2. As an example, the penetration hole 131 is a waist-shaped hole, etc., and the cross-section of the guide rod 9 is The surface shape is circular, etc., and the size of the through hole 131 is larger than the diameter of the guide rod 9. Such a design allows movement compensation to be formed between the guide rod 9 and the through hole 131 when the swinging member 4 is in motion. Specifically, a gap is formed between the size of the through hole 131 and the size of the guide rod 9. During the rotation of the swinging member 4 around its central rotation point, the auxiliary action member 8 rotates with the pin shaft of the second mounting hole 81 as a fulcrum, and the guide rod 9 can move in the through hole 131, and this movement includes but is not limited to up and down movement and left and right movement.

[0060] Or when the auxiliary action piece 8 is slidably connected to one end of the swinging piece 4, the sliding connection adopts a sliding mode similar to that of the connecting rod 72 and the swinging movable part 41, such as a slide groove is provided on one end of the swinging piece 4, and a connecting rod is connected to the auxiliary action piece 8, and the connecting rod is slidably connected to the slide groove. As a motion compensation, a penetration hole 131 for the guide rod 9 to be movably penetrated is provided on the base 13 or the pipette body 11, and the guide rod 9 is movably penetrated in the penetration hole 131. At this time, the guide rod 9 and the penetration hole 131 are slidably connected to guide the auxiliary action piece 8. Because the auxiliary action piece 8 is rotatably connected to the guide rod 9, the guide rod 9 causes the auxiliary action piece 8 to retract the gun head during the action process.

[0061] In this embodiment, a relative displacement is generated between the connecting block 71 and the swinging member 4. Under the action of the output end of the actuator 5, the connecting block 71 can move upward or downward in the vertical direction. When the middle part of the swinging member 4 rotates around the base 13, the motion trajectory of any point on the swinging member 4 except the middle rotation point of the swinging member 4 should be an arc around the middle part of the swinging member 4. At this time, the sliding connection point between the connecting block 71 and the swinging member 4 will not cause motion interference; on the contrary, when the auxiliary action member 8 is slidably connected to one end of the swinging member 4 by a sliding manner similar to the connecting rod 72 and the swinging movable part 41, no motion interference will occur.

[0062] In this embodiment, the needle withdrawal sleeve 2 is also provided with a wiring channel for the capacitive sensing device, so that the wiring of the pipette is more standardized and neat, and also plays a role in protecting the circuit.

[0063] During implementation, the swing member 4, under the control of the execution part 5, moves the auxiliary action part 8 downward, and drives the needle withdrawal sleeve 2 to move downward along the gun head rod 1 through the auxiliary action part 8. The needle withdrawal sleeve 2 pushes the used gun head downward to complete the gun head withdrawal action; then the execution part 5 reverses the work, and the swing member 4 drives the auxiliary action part 8 and the needle withdrawal sleeve 2 to move upward along the gun head rod 1. The needle withdrawal sleeve 2 returns to its original position under the action of the auxiliary action part 8 to facilitate the installation of the next gun head.

[0064] Example 2

[0065] Another embodiment of the present application is a pipette tip retracting mechanism, such as Figure 3-Figure 7 As shown, it comprises: a needle withdrawal sleeve 2 sleeved on the gun head rod 1 of the pipette body 11, and the needle withdrawal sleeve 2 slides on the gun head rod 1; it should be noted that the pipette body 11 comprises a base 13, and the base 13 is connected with a gun head rod 1, one end of the gun head rod 1 is connected with a gun head, and the other end of the gun head rod 1 is connected to a pipette gun, and one end of the gun head rod 1 is detachably connected with a gun head for sucking and releasing liquid; a channel is formed in the gun head rod 1; the other end of the gun head rod 1 is connected to the pipette gun, and the structure and working principle of this pipette body 11 are all prior art and will not be repeated; a convex block 21 is formed on the needle withdrawal sleeve 2;

[0066] The swing member 4 is rotatably connected to the base 13 of the pipette body 11; as an example, the middle part of the swing member 4 is rotatably connected to the base 13 of the pipette body 11; the two ends of the swing member 4 form a lever structure with the middle part as a fulcrum; there is a gap between the end of the swing member 4 close to the needle withdrawal sleeve 2 and the top of the protrusion 21, so that when the gun head is installed with the gun head rod 1, the needle withdrawal sleeve 2 can be pushed up to facilitate the installation of the gun head. One end of the tube 2 is in contact with the protrusion 21. When the gun head and the gun head rod 1 are installed, the gun head is not easy to install in place because there is no spacing stroke to give way; the actuator 5 drives the end of the swing member 4 away from the withdrawal sleeve 2 to press down the protrusion 21, so that the withdrawal sleeve 2 withdraws the gun head, or the actuator 5 drives the end of the swing member 4 away from the withdrawal sleeve 2 to tilt relative to the protrusion 21, so that the withdrawal sleeve 2 is away from the gun head, which facilitates the installation of the gun head and the gun head rod 1;

[0067] The actuator 5 is connected to the base 13 of the pipette body 11; the output end of the actuator 5 is connected to the other end of the swing member 4; as an example, the actuator 5 is a motor, which is a prior art and will not be described in detail; when the actuator 5 works, it drives the other end of the swing member 4 to move upward or downward with the middle of the swing member 4 as a fulcrum, so that one end of the swing member 4 is driven to press down the protrusion 21 or move away from the protrusion 21, so that the protrusion 21 drives the end of the needle withdrawal sleeve 2 to withdraw the gun head on the gun head rod 1 or moves the needle withdrawal sleeve 2 away from the gun head;

[0068] It also includes a sleeve connecting part 6, which includes a guide member 61, and the guide member 61 is movably arranged on the base 13 of the pipette body 11; the lower end of the guide member 61 is detachably connected to the needle withdrawal sleeve 2. It should be noted that during this process, the upper part of the guide member 61 and the base 13 form a relative limit, so that the guide member 61 can be stuck on the base 13 without causing the needle withdrawal sleeve 2 to slide directly along the gun head rod 1.

[0069] As a further illustration, in this embodiment, Figure 3-Figure 7 As shown, the lower end of the guide member 61 is connected to the protrusion 21 on the needle withdrawal sleeve 2 by a bolt; a first mounting hole 12 is provided on the base 13 of the pipette body 11, and the guide member 61 is movably inserted into the first mounting hole 12, and an elastic member 62 is inserted into the guide member 61, and the elastic member 62 is a spring, and the elastic member 62 is located in the first mounting hole 12; a sensing switch 63 is provided on the base 13 of the pipette body 11, and the guide member 61 is used in conjunction with the sensing switch 63. When the guide member 61 touches the sensing switch 63, the sensing switch 63 transmits a sensing signal to the controller, and the sensing switch 63 is used to sense whether the guide member 61 has returned to its position, so as to prevent the needle withdrawal sleeve 2 from being in an unreturned state, thereby affecting the operation of inserting the gun tip into the gun tip rod 1; it should be noted that the structure and working principle of the sensing switch 63 are both prior art and will not be repeated here.

[0070] In this embodiment, if Figure 6 and Figure 7 As shown, the elastic member 62 is passed through the guide member 61. Under normal circumstances, the elastic member 62 makes the needle withdrawal sleeve 2 be at a preset height on the gun head rod 1, so that the guide part 31 for the gun head on the gun head rod 1 is not completely blocked by the needle withdrawal sleeve 2, in order to ensure that the connection part between the gun head rod 1 and the gun head is partially exposed, so as to facilitate the installation of the gun head.

[0071] Furthermore, under normal conditions, the elastic member 62 is in a preset tension or preset compression state. Preferably, the elastic member 62 is in a preset compression state. The elastic member 62 in the compression state makes the needle withdrawal sleeve 2 at a preset height position on the gun head rod 1; when the swing member 4 presses down the protrusion 21 on the needle withdrawal sleeve 2, the guide member 61 connected to the protrusion 21 follows the action, and the guide member 61 compresses the elastic member 62. When the elastic member 62 moves to the compression limit state, the actuator 5 stops moving. It should be noted that when the elastic member 62 moves to the compression limit state, the elastic member 62 uses a sensor to cooperate with the actuator 5, which will not be repeated.

[0072] In addition, when the actuator 5 moves in the reverse direction, the compressed elastic member 62 has a certain elastic force, which lifts the guide member 61 .

[0073] As a further illustration, in this embodiment, Figure 3 and Figure 8 As shown, it also includes a connecting part 7, and the execution part 5 is connected to the swing member 4 through the connecting part 7, so that the connection between the two is more convenient; the connecting part 7 includes a connecting block 71 slidably connected to the swing member 4. It should be noted that the connecting block 71 is connected to the swing member 4 in a sliding manner, such as a slide groove; the output end of the execution part 5 is connected to the connecting block 71, and the output end of the execution part 5 is threadedly connected to the connecting block 71. A connecting rod 72 is connected to the connecting block 71, and the connecting rod 72 is connected to the swinging movable part 41 on the swing member 4.

[0074] As an example, the swinging movable part 41 is a slide groove arranged in the swinging member 4. When the swinging movable part 41 is a slide groove, the connecting rod 72 and the slide groove form a sliding connection; in this embodiment, the actuator 5 is a forward and reverse motor, and the output end of the actuator 5 is threadedly connected to the connecting block 71. Through the forward or reverse rotation of the actuator 5, the connecting rod 72 is driven to move upward or downward on the swinging movable part 41 on the swinging member 4; or when the actuator 5 is a lifting motor or a lifting cylinder, the output end of the actuator 5 is detachably connected to the connecting block 71, and through the forward or reverse rotation of the actuator 5, the connecting rod 72 is driven to move upward or downward on the swinging movable part 41 on the swinging member 4.

[0075] As a specific description, in this embodiment, Figure 4-Figure 7 and Fig. 9As shown, it also includes an auxiliary action piece 8, which is rotatably connected to one end of the swinging piece 4. The auxiliary action piece 8 is provided with a second mounting hole 81, and the auxiliary action piece 8 is rotatably connected to the swinging piece 4 through the cooperation of the second mounting hole 81 and the pin shaft; the swinging piece 4 can achieve a larger action expansion space for the needle withdrawal sleeve 2 through the auxiliary action piece 8, which is convenient for the layout of the overall space; there is a gap between the bottom of the auxiliary action piece 8 and the top of the protrusion 21 on the needle withdrawal sleeve 2, so that the gun head can withdraw the needle sleeve when it is installed with the gun head rod 1. 2 is lifted up to facilitate the installation of the gun head. If the end of the swinging member 4 close to the needle withdrawal sleeve 2 is in contact with the protrusion 21, when the gun head and the gun head rod 1 are installed, there is no spacing stroke to give way, making it difficult to install the gun head in place when installing; the executive part 5 drives the end of the swinging member 4 away from the needle withdrawal sleeve 2 to press down the protrusion 21, so that the needle withdrawal sleeve 2 withdraws the gun head, or the executive part 5 drives the end of the swinging member 4 away from the needle withdrawal sleeve 2 to tilt relative to the protrusion 21, so that the needle withdrawal sleeve 2 is away from the gun head, which facilitates the installation of the gun head and the gun head rod 1.

[0076] In this embodiment, if Figure 3 and Figure 9-13 As shown, the auxiliary action piece 8 is connected to a guide rod 9. When the auxiliary action piece 8 is rotatably connected to one end of the swinging piece 4, a penetration hole 131 for the guide rod 9 to be movably penetrated is provided on the base 13 or the pipette body 11. The guide rod 9 is movably penetrated in the penetration hole 131. The size of the penetration hole 131 is larger than the diameter of the guide rod 9 and is used for guiding the auxiliary action piece 8 to realize the action between the auxiliary action piece 8 and the needle withdrawal sleeve 2. As an example, the penetration hole 131 is a waist-shaped hole, etc., and the cross-section of the guide rod 9 is The surface shape is circular, etc., and the size of the through hole 131 is larger than the diameter of the guide rod 9. Such a design allows movement compensation to be formed between the guide rod 9 and the through hole 131 when the swinging member 4 is in motion. Specifically, a gap is formed between the size of the through hole 131 and the size of the guide rod 9. During the rotation of the swinging member 4 around its central rotation point, the auxiliary action member 8 rotates with the pin shaft of the second mounting hole 81 as a fulcrum, and the guide rod 9 can move in the through hole 131, and this movement includes but is not limited to up and down movement and left and right movement.

[0077] Or when the auxiliary action piece 8 is slidably connected to one end of the swinging piece 4, the sliding connection adopts a sliding mode similar to that of the connecting rod 72 and the swinging movable part 41, such as a slide groove is provided on one end of the swinging piece 4, and a connecting rod is connected to the auxiliary action piece 8, and the connecting rod is slidably connected to the slide groove. As a motion compensation, a penetration hole 131 for the guide rod 9 to be movably penetrated is provided on the base 13 or the pipette body 11, and the guide rod 9 is movably penetrated in the penetration hole 131. At this time, the guide rod 9 and the penetration hole 131 are slidably connected to guide the auxiliary action piece 8. Because the auxiliary action piece 8 is rotatably connected to the guide rod 9, the guide rod 9 causes the auxiliary action piece 8 to retract the gun head during the action process.

[0078] In this embodiment, a relative displacement is generated between the connecting block 71 and the swinging member 4. Under the action of the output end of the actuator 5, the connecting block 71 can move upward or downward in the vertical direction. When the middle part of the swinging member 4 rotates around the base 13, the motion trajectory of any point on the swinging member 4 except the middle rotation point of the swinging member 4 should be an arc around the middle part of the swinging member 4. At this time, the sliding connection point between the connecting block 71 and the swinging member 4 will not cause motion interference; on the contrary, when the auxiliary action member 8 is slidably connected to one end of the swinging member 4 by a sliding manner similar to the connecting rod 72 and the swinging movable part 41, no motion interference will occur.

[0079] In this embodiment, the needle withdrawal sleeve 2 is also provided with a wiring channel for the capacitive sensing device, so that the wiring of the pipette is more standardized and neat, and also protects the circuit.

[0080] During implementation, the swing member 4, under the control of the execution part 5, moves the auxiliary action part 8 downward, and the needle withdrawal sleeve 2 is moved downward along the gun head rod 1 through the auxiliary action part 8. The needle withdrawal sleeve 2 pushes the used gun head downward to complete the gun head withdrawal action; then the execution part 5 reverses the work, the swing member 4 drives the auxiliary action part 8 to move upward, and the needle withdrawal sleeve 2 returns upward along the gun head rod 1 under the action of the sleeve connecting part 6 to facilitate the installation of the next gun head.

[0081] As a further illustration, Fig.12 As shown, it also includes a sensing unit 64, and the sensing unit 64 is connected to the base 13 or the pipette body 11; both Example 1 and Example 2 have a sensing unit 4; the sensing unit 64 includes but is not limited to a photoelectric sensing switch, and the upper end of the guide rod 9 is used in conjunction with the sensing unit 64. When the upper end of the guide rod 9 is in the highest position, the guide rod 9 is vertical to the horizontal plane, and the guide rod 9 triggers the sensing unit 64 to respond. The sensing unit 64 transmits the position status signal of the guide rod 9 to the controller, and the controller controls the execution part 5 to stop the action to prevent the torque of the execution part 5 from being excessive; it should be noted that the structure and working principle of the sensing unit 64 are both existing technologies and will not be repeated.

[0082] A pipette according to another embodiment of the present application includes the pipette tip retracting mechanism as described above.

[0083] From the above description, it can be seen that the above embodiments of the present application achieve the following technical effects: 1. The lever principle is used to perform the gun head retraction action, thereby avoiding the increase of the pipetting cavity space and the design of the needle withdrawal plate, thereby improving the pipetting accuracy and the rationality of the overall layout space;

[0084] 2. The elastic member allows the needle withdrawal sleeve to be at a preset height on the gun head rod, so that the guide part for the gun head on the gun head rod is not completely blocked by the needle withdrawal sleeve, in order to ensure that the connection part between the gun head rod and the gun head is partially exposed, which is convenient for the installation of the gun head;

[0085] 3. The design of the routing channel can prevent the capacitor routing from being exposed;

[0086] 4. The design of auxiliary action parts shortens the power stroke of the actuator and saves costs;

[0087] 5. The design of sleeve connection part and induction switch is adopted to sense whether the gun head is installed in place, and also to ensure the return of the needle withdrawal sleeve to ensure that the gun head can be inserted into the gun head rod.

[0088] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0089] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps set forth in these embodiments do not limit the scope of the present application. Meanwhile, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, methods and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be considered as a part of the specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, and therefore, once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0090] In the description of the present application, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction, and therefore cannot be understood as limiting the scope of protection of the present application; the directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0091] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" may include both "above" and "below". The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0092] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of this application.

[0093] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0094] The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made according to the scope of the patent application of the present invention should fall within the scope of the present invention.

Claims

1. A pipette tip retracting mechanism, characterized in that: The invention comprises: a needle withdrawal sleeve (2) sleeved on a gun head rod (1) of a pipette body (11), wherein the needle withdrawal sleeve (2) slides on the gun head rod (1); A swinging member (4), the swinging member (4) is rotatably connected to a base (13) of a pipette body (11); the middle part of the swinging member (4) is rotatably connected to the base (13) of the pipette body (11); the two ends of the swinging member (4) form a lever structure with the middle part as a fulcrum; one end of the swinging member (4) close to the needle withdrawal sleeve (2) is connected to the top of the needle withdrawal sleeve (2); An actuator (5) is connected to a base (13) of a pipette body (11); an output end of the actuator (5) is connected to the other end of a swinging member (4); the actuator (5) drives the end of the swinging member (4) away from the needle withdrawal sleeve (2) to press down the needle withdrawal sleeve (2), or the actuator (5) drives the needle withdrawal sleeve (2) to slide upward along the gun head rod (1) through the swinging member (4).

2. A pipette tip retracting mechanism, characterized in that: The invention comprises: a needle withdrawal sleeve (2) sleeved on a gun head rod (1) of a pipette body (11), wherein the needle withdrawal sleeve (2) slides on the gun head rod (1); A swinging member (4), wherein the swinging member (4) is rotatably connected to a base (13) of a pipette body (11); the middle portion of the swinging member (4) is rotatably connected to the base (13) of the pipette body (11); the two ends of the swinging member (4) form a lever structure with the middle portion as a fulcrum; there is a distance between one end of the swinging member (4) close to the needle withdrawal sleeve (2) and the top of the needle withdrawal sleeve (2); An actuator (5) is connected to a base (13) of a pipette body (11); an output end of the actuator (5) is connected to the other end of the swing member (4); the actuator (5) drives the end of the swing member (4) away from the needle withdrawal sleeve (2) to press down the needle withdrawal sleeve (2), or the actuator (5) tilts relative to the needle withdrawal sleeve (2) through the end of the swing member (4) away from the needle withdrawal sleeve (2); A sleeve connecting part (6), the sleeve connecting part (6) comprises a guide member (61), the guide member (61) is movably arranged on a base (13) of the pipette body (11); the lower end of the guide member (61) is detachably connected to the needle withdrawal sleeve (2).

3. The pipette tip retracting mechanism of claim 2, wherein: A protrusion (21) is formed on the needle withdrawal sleeve (2); a distance is provided between the end of the swing member (4) close to the needle withdrawal sleeve (2) and the top of the protrusion (21); the actuator (5) drives the end of the swing member (4) away from the needle withdrawal sleeve (2) to press down the protrusion (21), or the actuator (5) tilts relative to the protrusion (21) through the end of the swing member (4) away from the needle withdrawal sleeve (2); One end of the guide member (61) is detachably connected to a protrusion (21) on the needle withdrawal sleeve (2); A first mounting hole (12) is provided on the base (13) of the pipette body (11), the guide member (61) is movably inserted into the first mounting hole (12), an elastic member (62) is provided on the guide member (61), and the elastic member (62) is located in the first mounting hole (12).

4. The pipette tip retracting mechanism of claim 3, wherein: It also includes an induction switch (63), which is connected to the base (13) of the pipette body (11), and the guide member (61) is used in conjunction with the induction switch (63).

5. The pipette tip retracting mechanism of any one of claims 1 to 4, characterized in that: It also comprises a connecting part (7), and the executing part (5) is connected to the swing member (4) via the connecting part (7); the connecting part (7) comprises a connecting block (71) slidably connected to the swing member (4), and the output end of the executing part (5) is connected to the connecting block (71).

6. The pipette tip retracting mechanism of claim 5, wherein: The connecting block (71) is connected to a connecting rod (72), and the connecting rod (72) is movably connected to a swinging movable part (41) on the swinging member (4).

7. The pipette tip retracting mechanism of any one of claims 1 to 4, characterized in that: It also includes an auxiliary action piece (8), the auxiliary action piece (8) is connected to a guide rod (9), when the auxiliary action piece (8) is rotatably connected to one end of the swinging piece (4), a penetration hole (131) for the guide rod (9) to movably penetrate is provided on the base (13) or the pipette body (11), and the guide rod (9) is movably penetrated in the penetration hole (131); the size of the penetration hole (131) is larger than the diameter of the guide rod (9), and under the action of an external force, the guide rod (9) can move in the penetration hole (131); Or when the auxiliary action member (8) is slidably connected to one end of the swing member (4), the auxiliary action member (8) is connected to a guide rod (9), and the base (13) or the pipette body (11) is provided with a penetration hole (131) for the guide rod (9) to movably penetrate, and the guide rod (9) is movably penetrated in the penetration hole (131).

8. The pipette tip retracting mechanism of any one of claims 1 to 4, characterized in that: The needle withdrawal sleeve (2) is also provided with a wiring channel.

9. The pipette tip retracting mechanism of claim 3, wherein: The elastic member (62) is inserted into the guide member (61). Under normal conditions, the elastic member (62) enables the needle withdrawal sleeve (2) to be located at a preset height on the gun head rod (1).

10. The pipette tip retracting mechanism of claim 7, wherein: It also comprises a sensing unit (64), wherein the sensing unit (64) is connected to the base (13) or the pipette body (11); the guide rod (9) is used in conjunction with the sensing unit (64).

11. A pipette, characterized in that: The invention comprises a pipette tip retracting mechanism as claimed in any one of claims 1 to 10.

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