A pipetting device for cerebrospinal fluid testing

Abstract

The application relates to the technical field of medical detection equipment, and particularly discloses a pipetting device for cerebrospinal fluid detection, which comprises a main body, a pipette, a sliding rod, a push rod and a spring; the sliding rod and the push rod can move back and forth; the front end of the sliding rod is connected with a first piston in the interior of the pipette, a first rack is fixedly arranged on the side wall of the sliding rod, and a second rack is fixedly arranged on the side wall of the push rod; a transmission gear is arranged in the interior of the main body, the first rack and the second rack are respectively engaged with the transmission gear; the push rod is fixedly connected with a synchronous frame, and a push-up piece and a locking piece are arranged in the main body. The pipetting device for cerebrospinal fluid detection does not have a separate exhaust and reset link in the operation process, the pipetting efficiency is high, and the service life can be significantly prolonged; the liquid in the pipette can be fully discharged, so that the pipetting precision is improved, the operation is simple and fast, and human errors are not prone to occur; after the pipetting is completed, the pipetting device can be automatically reset to the initial state, is suitable for being properly placed, does not need to be additionally operated to adjust the maximum range, and is convenient and fast.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of medical detection equipment, and particularly relates to a pipetting device for cerebrospinal fluid detection. BACKGROUND

[0002] In the sample collection, processing and detection of cerebrospinal fluid clinical detection, the sample solution or related liquid needs to be quantitatively transferred. At present, the pipette gun is mostly used to complete the above pipetting operation, and there are certain defects and deficiencies in clinical practice. First, the commonly used pipette gun needs to be pressed twice in one pipetting operation, and needs to go through four steps of exhaust, liquid absorption, liquid discharge and reset. The operation process is redundant, the efficiency is low, and the cerebrospinal fluid detection process is affected. Especially the initial exhaust and the final reset are essentially idle stroke actions, which aggravate the wear of the device and affect the service life of the pipette gun. Secondly, the current pipette gun usually has two gears, which are defined and positioned based on the change of pressing resistance. In the pipetting operation, different gears need to be used to complete the corresponding liquid absorption and liquid discharge. For example, in the cerebrospinal fluid detection, the "one-gear liquid absorption and two-gear liquid discharge" is usually used to reduce the liquid residue to ensure the pipetting accuracy. The operation process needs to accurately control the force and the stopping time, which has a certain operation difficulty, and is easy to cause insufficient pipetting accuracy due to human errors, thereby affecting the accuracy of the detection result. In addition, after completing the pipetting, the pipette gun usually needs to be adjusted back to the maximum range to release the spring pressure, so as to avoid the elastic fatigue caused by long-term compression, which further increases the operation complexity. At the same time, the frequent adjustment of the range will reduce the matching accuracy and service life of the related components. SUMMARY

[0003] In order to solve the problems of the existing pipette gun, such as operation trouble, low efficiency and easy human error, the present application provides a pipetting device for cerebrospinal fluid detection, which has high pipetting efficiency and is easy to operate.

[0004] In order to achieve the above technical purpose, the present application adopts the following technical scheme:

[0005] The application relates to a pipetting device for cerebrospinal fluid detection, which comprises a fixedly-connected main body and a pipette; a joint is arranged at the front end of the pipette, and a first piston is arranged in the interior; the pipetting device further comprises a sliding rod capable of moving forward and backward in sliding cooperation with the main body and a push rod, and a spring for driving the push rod to move backward; the front end of the sliding rod is fixedly connected with the first piston, a first rack is fixedly arranged on the side wall of the sliding rod, and a second rack is fixedly arranged on the side wall of the push rod; a transmission gear is arranged in the interior of the main body, the first rack and the second rack are arranged on the opposite sides of the transmission gear and are in mesh with the transmission gear respectively; a suction volume setting rod is installed on the main body, the suction volume setting rod is located right behind the sliding rod, and a volume scale is arranged on the side wall of the suction volume setting rod; the push rod is fixedly connected with a synchronous frame, the synchronous frame is provided with a first abutting portion, a second abutting portion and a third abutting portion; a push-up piece and a locking piece capable of rotating are arranged in the main body, the push-up piece and the locking piece are driven by elastic pieces to be capable of automatically resetting to initial positions, the push-up piece is provided with a fourth abutting portion and a fifth abutting portion, and the locking piece is provided with a sixth abutting portion and a locking portion.

[0006] The working principle of the pipetting device for cerebrospinal fluid detection is as follows:

[0007] In the initial state of the pipetting device, the push rod, the sliding rod, the push-up piece and the locking piece are all in the initial positions, the first abutting portion is located at the rear side of the fifth abutting portion and abuts against the fifth abutting portion, the fourth abutting portion is located at the rear side of the second abutting portion and abuts against the second abutting portion, and the third abutting portion is located right in front of the sixth abutting portion;

[0008] When the pipette is used for sucking liquid, an external force drives the push rod to move forward from the initial position, and the sliding rod moves backward from the initial position, so that the pipette completes the liquid sucking; in the process of moving forward of the push rod, the first abutting portion drives the push-up piece to rotate through the fifth abutting portion, the position of the fourth abutting portion is moved backward, and the push-up piece is locked by the locking piece, and the push-up piece does not constitute an obstacle to the forward and backward movement of the synchronous frame thereafter;

[0009] When the pipette is used for discharging liquid, the spring drives the push rod to move backward, and the sliding rod moves forward, so that the pipette discharges liquid; when the push rod reaches the initial position, the push rod can still move backward, so that the sliding rod can still move forward after reaching the initial position, so as to fully discharge the liquid in the pipette; when the third abutting portion contacts the sixth abutting portion, the third abutting portion drives the locking piece to rotate through the sixth abutting portion, so as to release the locking effect on the push-up piece; in the process of rotating the push-up piece to the initial position, the fourth abutting portion drives the push rod to move forward through the second abutting portion, so as to reset the push rod and the sliding rod to the initial positions; the third abutting portion is separated from the sixth abutting portion with the forward movement of the push rod, and the locking piece is reset to the initial position, that is, the pipetting device returns to the initial state.

[0010] In a further technical scheme, the central axes of the pipette, the first piston, the sliding rod and the suction volume setting rod are coincident.

[0011] In a further technical solution, the main body is internally provided with a first guide slot extending in the front-rear direction, the first guide slot being in sliding fit with the middle-rear part of the sliding rod; the main body is internally provided with a second guide slot extending in the front-rear direction, the second guide slot being in sliding fit with the push rod, the spring being located in the second guide slot and on the front side of the push rod; a gear base is arranged between the first guide slot and the second guide slot, and the transmission gear is mounted on the gear base.

[0012] In a further technical solution, the main body is composed of at least two part housings, and the outer contour shape of the main body adopts a grip type structure design.

[0013] In a further technical solution, the synchronous frame is fixedly connected with the front end part of the push rod, and the synchronous frame is located on the front side of the transmission gear; the synchronous frame comprises a first extension arm and a second extension arm extending forward; a first abutting part is arranged at the front end of the first extension arm, and a second abutting part and a third abutting part are arranged at the front end of the second extension arm.

[0014] In a further technical solution, the push-up piece and the locking piece are respectively mounted on the same support through a rotating shaft, the support is fixedly connected with the main body, the elastic piece is a torsion spring or a spring sheet, and the support is provided with a limiting part limiting the rotating range of the push-up piece and the locking piece.

[0015] In a further technical solution, the push rod is internally provided with a column cavity open only at the front end, the main body is internally fixed with a guide rod, the guide rod extends into the push rod and the two are in sliding fit, the spring is sleeved on the outside of the guide rod, and the rear end of the spring is in contact fit with the front end of the push rod.

[0016] In a further technical solution: a rotatable internally threaded sleeve is mounted at the rear end of the main body, the rear end of the internally threaded sleeve is provided with a knob, the knob is located on the rear side of the main body; a thread is arranged on the outer wall of the inhalation amount setting rod, the inhalation amount setting rod is in threaded fit with the internally threaded sleeve, the front end of the inhalation amount setting rod is located in the main body and fixedly connected with an anti-rotation sliding part, and a sliding groove in sliding fit with the anti-rotation sliding part is formed in the main body;

[0017] Further, a recessed area is arranged on the side wall of the inhalation amount setting rod, the volume scale is marked in the recessed area; a pointer is arranged on one side of the knob, an annular scale is arranged on the rear end face of the main body, and the annular scale surrounds the outside of the knob; during one rotation of the internally threaded sleeve, the displacement amount of the inhalation amount setting rod is exactly one graduation value of the volume scale.

[0018] In further technical solutions: the push rod is internally provided with a column cavity open only at the front end, the main body is internally fixed with a guide rod, and the rear end of the guide rod is fixed with a second piston; the second piston is located in the column cavity of the push rod and is in sealing sliding fit, the guide rod is hollow and in communication with the column cavity; a top ring is sleeved on the joint, a piston cylinder is fixed on the main body, and a third piston and a push spring are arranged in the piston cylinder, and the third piston is fixedly connected with the top ring through a top rod; the inner cavity of the guide rod is in communication with the piston cylinder through a first gas path and in communication with the atmosphere through a second gas path;

[0019] Further, the first gas path and the second gas path can adopt a pipeline or a flow channel formed in the main body.

[0020] Further, an air vent valve is arranged on the second gas path; the air vent valve is a normally open type press valve, is fixed on the main body, and a pressing part is located outside the main body.

[0021] Further, an air vent hole is formed at the front end of the main body, and the second gas path is in communication with the atmosphere through the air vent hole.

[0022] Compared with the prior art, the cerebrospinal fluid detection pipetting device has the following beneficial technical effects:

[0023] 1. The pipetting device is based on the setting of the first rack, the second rack and the transmission gear, so that the push rod and the sliding rod are in transmission connection and the movement directions are opposite, so as to optimize the working mechanism of the pipetting device; during the pipetting process, the liquid is sucked by manually pressing the pressure handle, and the liquid is automatically discharged after stopping pressing, and there is no separate exhaust and reset link in the operation process, thereby significantly improving the operation efficiency of pipetting and speeding up the detection process of cerebrospinal fluid; at the same time, because the idle stroke is avoided, the component wear can be significantly delayed, and the service life of the pipetting device is prolonged.

[0024] 2. The pipetting device is based on the setting of the synchronous frame, the push top piece and the locking piece and other cooperative components, so that the stroke position of the sliding rod can be indirectly interfered, the initial position is taken as the starting point when the liquid is sucked, the sliding rod still continues to move forward after reaching the initial position when the liquid is discharged, and finally returns to the initial position, thereby realizing the functional design that the displacement of the first piston when discharging is greater than that when sucking, the liquid in the suction tube can be fully discharged, which is equivalent to the operation mode of the traditional pipetting gun "one gear sucking and two gears discharging", and the pipetting precision can be effectively improved. The pipetting device realizes the above-mentioned effects without artificial operation, is simple and convenient, can effectively avoid the operation sequence error, improper position stop and other human errors in the traditional operation, and significantly improves the stability and accuracy of the pipetting operation.

[0025] 3、The pipetting device can automatically reset to the initial state after the pipetting is completed, the spring is in the stretched state in the initial state, and the interaction force between the matching parts is small; therefore, no additional "adjusting the maximum range" operation is required when placing, which is more convenient and fast, and also avoids the decrease of numerical accuracy caused by frequent range adjustment; in addition, when the pipetting device is placed in the initial state, the first piston is located at the front end position of the pipette, which can effectively prevent dust and impurities in the external environment from entering the pipette through the joint, thereby avoiding pollution to the inside of the pipette. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings of the embodiments will be briefly introduced below. Obviously, the drawings described in the following description only relate to some embodiments of the present application, and are not a limitation on the present application.

[0027] Figure 1 It is one of the overall structure schematic diagrams of the pipetting device in the present application.

[0028] Figure 2 It is the second overall structure schematic diagram of the pipetting device in the present application.

[0029] Figure 3 It is the structure exploded schematic diagram of the pipetting device in the present application.

[0030] Figure 4 It is the internal structure schematic diagram of the pipetting device in the present application.

[0031] Figure 5 It is the partial structure schematic diagram of the rear end of the pipetting device in the present application.

[0032] Figure 6 It is the matching structure schematic diagram of the synchronous frame, the push piece and the locking piece.

[0033] Figure 7 It is the initial state schematic diagram of the pipetting device in the present application.

[0034] Figure 8 It is the matching state schematic diagram of the synchronous frame, the push piece and the locking piece of the pipetting device in the initial state.

[0035] Figure 9 It is the matching state schematic diagram of the push piece, the synchronous frame and the locking piece in the locking state.

[0036] Figure 10 It is the state schematic diagram when the synchronous frame moves backward to drive the locking piece to release the locking of the push piece.

[0037] Figure 11 It is the structure schematic diagram of the pipetting device in another embodiment of the present application.

[0038] Figure 12 Fig. 1 is a schematic view of the internal structure of a pipetting device according to an embodiment of the present application. Figure 11

[0039] Figure 13 Fig. 2 is a schematic view of the front end partial structure of a pipetting device according to an embodiment of the present application. Figure 12

[0040] Reference signs:

[0041] 1 - tip; 2 - connector; 3 - pipette; 4 - main body; 5 - knob; 6 - suction volume setting rod; 7 - pressing handle; 8 - push rod; 9 - second guide groove; 10 - first guide groove; 11 - gear seat; 12 - sliding groove; 13 - internal threaded sleeve; 14 - anti-rotation sliding part; 15 - second rack; 16 - sliding rod; 17 - first rack; 18 - guide rod; 19 - spring; 20 - transmission gear; 21 - support; 22 - push-up piece; 23 - second extension arm; 24 - first extension arm; 25 - synchronization frame; 26 - volume scale; 27 - locking piece; 28 - first piston; 29 - second abutting part; 30 - fourth abutting part; 31 - first abutting part; 32 - fifth abutting part; 33 - locking part; 34 - sixth abutting part; 35 - third abutting part; 36 - recessed area; 37 - annular scale; 38 - pointer; 39 - top ring; 40 - top rod; 41 - piston cylinder; 42 - air hole; 43 - column cavity; 44 - second piston; 45 - second air path; 46 - push spring; 47 - third piston; 48 - first air path. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions of the embodiments of the present application will be described clearly and completely below with reference to the drawings of the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the described embodiments of the present application, all other embodiments obtained by a person of ordinary skill in the art without any inventive effort fall within the protection scope of the present application.

[0043] Referring to Figures 1 to 7 Fig. 1, in an embodiment of the present application, the pipetting device for cerebrospinal fluid detection comprises a main body 4, and a pipette 3, a sliding rod 16 and a push rod 8 extending along the front-rear direction;

[0044] The pipette 3 is fixedly connected with the main body 4, and the front end extends to the front side of the main body 4 and is provided with a connector 2 for combined connection with a disposable tip 1, and the inside of the pipette 3 is provided with a sealingly matched first piston 28;

[0045] ​​The sliding rod 16 is in sliding fit with the main body 4 and can move forward and backward, the front end of the sliding rod 16 extends into the pipette 3 and is fixedly connected with the first piston 28, so that the sliding rod 16 can drive the first piston 28 to move forward and backward, and the pipette 3 can suck liquid and discharge liquid; the side wall of the middle and rear part of the sliding rod 16 is fixedly provided with a first rack 17, and the first rack 17 extends in the forward and backward direction;

[0046] The push rod 8 is in sliding fit with the main body 4 and can move forward and backward, the rear end of the push rod 8 is the pressing handle 7, and the pressing handle 7 is located at the rear side of the main body 4, so as to facilitate manual driving of the push rod 8 to move forward; a spring 19 is arranged in the main body 4, and the spring 19 is used for driving the push rod 8 to move backward; the side wall of the push rod 8 is fixedly provided with a second rack 15, and the second rack 15 extends in the forward and backward direction;

[0047] The main body 4 is rotatably connected with a transmission gear 20 inside; the first rack 17 and the second rack 15 are distributed on the opposite sides of the transmission gear 20 and are respectively in meshing fit with the transmission gear 20; thus, when the pressing handle 7 is pressed to drive the push rod 8 to move forward, the sliding rod 16 will move backward under the transmission action of the first rack 17, the second rack 15 and the transmission gear 20, so that the pipette 3 can suck liquid; after the pressing of the pressing handle 7 is stopped, the push rod 8 is driven by the spring 19 to move backward, and the sliding rod 16 moves forward, so that the pipette 3 can discharge liquid;

[0048] The main body 4 is rotatably connected with a transmission gear 20 inside; the first rack 17 and the second rack 15 are distributed on the opposite sides of the transmission gear 20 and are respectively in meshing fit with the transmission gear 20; thus, when the pressing handle 7 is pressed to drive the push rod 8 to move forward, the sliding rod 16 will move backward under the transmission action of the first rack 17, the second rack 15 and the transmission gear 20, so that the pipette 3 can suck liquid; after the pressing of the pressing handle 7 is stopped, the push rod 8 is driven by the spring 19 to move backward, and the sliding rod 16 moves forward, so that the pipette 3 can discharge liquid;

[0049] The push rod 8 is fixedly connected with a synchronous frame 25, the synchronous frame 25 is provided with a first abutting portion 31, a second abutting portion 29 and a third abutting portion 35; the main body 4 is rotatably connected with a pushing piece 22 and a locking piece 27, the pushing piece 22 and the locking piece 27 can respectively rotate within a predetermined angle range and can be automatically reset to the respective initial positions by elastic members; the pushing piece 22 is provided with a fourth abutting portion 30 and a fifth abutting portion 32, and the locking piece 27 is provided with a sixth abutting portion 34 and a locking portion 33.

[0050] The working principle of the present pipetting device is as follows:

[0051] Referring to Figure 4 ,Figures 6 to 8 As shown, when the pipetting device is in the initial state, the push rod 8, the sliding rod 16, the push piece 22 and the locking piece 27 are all in their respective initial positions; at this time, the first abutting portion 31 is located at the rear side of the fifth abutting portion 32 and the two abut against each other, the fourth abutting portion 30 is located at the rear side of the second abutting portion 29 and the two abut against each other, and the third abutting portion 35 is located in front of the sixth abutting portion 34 and the two are kept at a distance; based on the above matching relationship, the spring 19 can prevent the push rod 8 from moving forward, and the cooperation between the fourth abutting portion 30 and the second abutting portion 29 can prevent the push rod 8 from moving backward, thereby enabling the pipetting device to be stably maintained in the initial state.

[0052] When sucking liquid, as shown, Figures 7 to 9 press the pressure handle 7 to drive the push rod 8 to move forward from the initial position, and the sliding rod 16 moves backward from the initial position; when the sliding rod 16 contacts the suction amount setting rod 6, the liquid amount in the suction tube 3 is the set suction amount, and the liquid sucking is completed; during the process of the push rod 8 moving forward from the initial position, the first abutting portion 31 drives the push piece 22 to rotate through the fifth abutting portion 32, so that the position of the fourth abutting portion 30 moves backward, and the push piece 22 is locked by the locking piece 27; thereafter, the push piece 22 maintains the locked state and does not hinder the forward and backward movement of the synchronous frame 25;

[0053] When discharging liquid, as shown, Figure 7 , Figure 8 , Figure 10 stop pressing the pressure handle 7, and the pushing force of the spring 19 drives the push rod 8 to move backward, and the sliding rod 16 moves forward, so that the suction tube 3 discharges liquid; during the discharging process, the push rod 8 continues to move backward after reaching the initial position, so that the sliding rod 16 continues to move forward after reaching the initial position by a certain distance (the distance between the third abutting portion 35 and the sixth abutting portion 34 in the initial state), so as to fully discharge the liquid in the suction tube 3; when the third abutting portion 35 contacts the sixth abutting portion 34, the third abutting portion 35 drives the locking piece 27 to rotate through the sixth abutting portion 34, so as to release the locking of the push piece 22; thereafter, the push piece 22 is driven by the elastic member to rotate in the direction of the initial position, the fourth abutting portion 30 drives the push rod 8 to move forward through the second abutting portion 29, so as to reset the push rod 8 and the sliding rod 16 to their respective initial positions, the third abutting portion 35 separates from the sixth abutting portion 34 as the push rod 8 moves forward, and the locking piece 27 resets to the initial position under the driving of the elastic member; thus, the push rod 8, the sliding rod 16, the push piece 22 and the locking piece 27 are all reset to their respective initial positions, so that the pipetting device returns to the initial state.

[0054] Based on the above design features, the core technical advantages of the pipetting device mainly include:

[0055] 1、The pipette device is based on setting the first rack 17, the second rack 15 and the transmission gear 20, so that the movement of the push rod 8 and the sliding rod 16 is kept synchronous and reverse, thereby optimizing the liquid suction and discharge process; during the pipetting process, the liquid suction is completed by manually pressing the pressure handle 7, and the liquid discharge is automatically performed after stopping pressing, and there is no separate exhaust and reset link in the operation process, thereby significantly improving the operation efficiency of pipetting; at the same time, since the idle stroke is avoided, the component wear can be significantly delayed, and the service life of the pipette device is prolonged.

[0056] 2、The pipette device is based on setting the synchronous frame 25, the push-up piece 22 and the locking piece 27 and other cooperative components, so that the stroke of the sliding rod 16 can be interfered, the initial position is taken as the starting point of the sliding rod 16 during liquid suction, the sliding rod 16 continues to move forward after reaching the initial position during liquid discharge, and finally returns to the initial position, thereby realizing the functional design that the displacement of the first piston 28 during liquid discharge is greater than that during liquid suction, so that the liquid sucked into the suction tube 3 can be fully discharged, which is equivalent to the operation mode of the traditional pipette gun "one-gear liquid suction and two-gear liquid discharge", and the liquid residue can be effectively reduced to improve the pipetting precision. The pipette device realizes the above-mentioned effects without artificial deliberate operation, is simple and convenient, can effectively avoid the operation sequence error and improper position stop in the traditional operation, and significantly improves the stability and accuracy of pipetting operation.

[0057] 3、The pipette device can automatically reset to the initial state after pipetting is completed, the spring 19 is in an extended state in the initial state, and the interaction force between the matching components is small; therefore, additional "adjustment of the maximum range" is not required when placing, which is more convenient and fast, and also avoids the decrease of numerical precision caused by frequent range adjustment; in addition, when the pipette device is placed in the initial state, the first piston 28 is located at the front end position of the suction tube 3, so that dust and impurities in the outside can be effectively prevented from entering the suction tube 3 through the joint 2, and pollution to the inside of the suction tube 3 is avoided.

[0058] Referring to Figures 1 to 4 Further technical features include, in the course of implementing the present application:

[0059] The central axes of the suction tube 3, the first piston 28, the sliding rod 16 and the suction amount setting rod 6 coincide, so as to improve the cooperation stability of these components;

[0060] The main body 4 is internally provided with the first guide groove 10 extending in the front-rear direction, the first guide groove 10 is in sliding cooperation with the middle-rear part of the sliding rod 16, and the sliding rod 16 is provided with a guide and limiting action, so that the sliding rod 16 can only move forward and backward, and cannot rotate;

[0061] The main body 4 has a second guide groove 9 extending in the front-back direction inside. The second guide groove 9 slides with the push rod 8 to provide guidance and limit for the push rod 8, so that the push rod 8 can only move back and forth and cannot rotate.

[0062] The spring 19 is located in the second guide groove 9 and is located in front of the push rod 8;

[0063] A gear seat 11 is provided between the first guide groove 10 and the second guide groove 9, and the transmission gear 20 is mounted on the gear seat 11.

[0064] The main body 4 is composed of at least two shell parts to facilitate the assembly of internal components of the main body 4;

[0065] The outer contour of the main body 4 adopts a grip-type structure design for easy holding and use.

[0066] See Figure 4 , Figure 6 As shown, as a preferred technical feature of the present invention, the synchronizing frame 25 is fixedly connected to the front end of the push rod 8, and the synchronizing frame 25 is located on the front side of the transmission gear 20; the synchronizing frame 25 includes a first extending arm 24 and a second extending arm 23 extending forward, the first abutting part 31 is disposed at the front end of the first extending arm 24, and the second abutting part 29 and the third abutting part 35 are disposed at the front end of the second extending arm 23.

[0067] See Figure 4 , Figure 6 As shown, as a preferred technical feature of the present invention, the pushing member 22 and the locking member 27 are respectively mounted on the same support 21 via a rotating shaft. The support 21 is fixedly connected to the main body 4. The elastic member is a torsion spring or a spring sheet. The support 21 is provided with a limiting part that limits the rotation range of the pushing member 22 and the locking member 27.

[0068] See Figure 3 , Figure 4 As shown, as a preferred technical feature of the present invention, the push rod 8 has a cylindrical cavity 43 that is open only at the front end. A guide rod 18 extending in the front-rear direction is fixed inside the main body 4. The guide rod 18 extends into the push rod 8 and the two slide together. The spring 19 is sleeved on the outside of the guide rod 18, and the rear end of the spring 19 contacts the front end of the push rod 8. Thus, the guide rod 18 can provide guidance and support for the push rod 8, enabling the push rod 8 to move back and forth more stably. At the same time, the guide rod 18 can significantly improve the stability of the cooperation between the spring 19 and the push rod 8.

[0069] In the technical concept adopted in this invention, the specific cooperation structure between the inhalation volume setting rod 6 and the main body 4 can be implemented in various ways. For example, the inhalation volume setting rod 6 and the main body 4 can be slidably connected, and a locking bolt can be provided on the main body 4 to adjust and fix the position of the inhalation volume setting rod 6; another example is that a screw hole can be provided on the main body 4, through which the inhalation volume setting rod 6 passes and is threadedly engaged, thereby adjusting the front and rear position by rotating the inhalation volume setting rod 6. Obviously, although the above implementation methods are simple and easy to implement, they have certain shortcomings in terms of accuracy and convenience. Therefore, this invention has the following technical innovations regarding the cooperation method between the inhalation volume setting rod 6 and the main body 4:

[0070] See Figures 3 to 5 As shown, a rotatable internal threaded sleeve 13 is installed at the rear end of the main body 4. A knob 5 is fixedly connected to the rear end of the internal threaded sleeve 13. The knob 5 is located on the rear side of the main body 4 for easy manual turning. The outer wall of the suction volume setting rod 6 is threaded. The suction volume setting rod 6 is threadedly engaged with the internal threaded sleeve 13. The front end of the suction volume setting rod 6 is located inside the main body 4 and is fixedly connected to an anti-rotation sliding part 14. A groove 12 is opened inside the main body 4 to slide in cooperation with the anti-rotation sliding part 14.

[0071] Therefore, when the knob 5 is manually rotated, the internal threaded sleeve 13 will drive the suction volume setting rod 6 to move back and forth, thereby achieving the purpose of adjusting the suction volume, which is convenient and quick to operate. Since the suction volume setting rod 6 will not rotate, the direction of the volume scale 26 will not change, making it easy to observe in real time during the adjustment process. By rotating the internal threaded sleeve 13 to drive the suction volume setting rod 6 to move, fine adjustments can be made, which can significantly improve the adjustment accuracy.

[0072] In a further design, a recessed area 36 is provided on the side wall of the inhalation volume setting rod 6, and the volume scale 26 is marked in the recessed area 36, ​​thereby enabling the volume scale 26 and the external thread to be set on the outside of the inhalation volume setting rod 6 in a better compatible manner.

[0073] In a further design, a pointer 38 is provided on one side of the knob 5, and an annular scale 37 is provided on the rear end face of the main body 4, which surrounds the outside of the knob 5. During the rotation of the internal threaded sleeve 13, the displacement of the suction volume setting rod 6 is exactly one division value of the volume scale 26. Thus, the main body 4, the internal threaded sleeve 13, the suction volume setting rod 6, and the knob 5 essentially constitute a micrometer, commonly known as a micrometer. The working principle and usage of a micrometer are consistent with those of a common micrometer. Based on the cooperation of the pointer 38 and the annular scale 37, the rotation angle of the knob 5 can be determined, and further division can be made based on the division value of the volume scale 26, thereby significantly improving the adjustment accuracy of the suction volume.

[0074] At present, most of the pipetting devices are provided with a separation mechanism for the tip 1, so that the tip 1 can be separated quickly and without pollution after the completion of the pipetting operation. The separation mechanism is usually composed of a plurality of components such as a button provided at the tail end of the pipetting device, a sleeve provided at the front end of the pipetting device, a connecting arm connecting the button and the sleeve, and an elastic member for driving the above-mentioned components to reset, which has a complex structure and a large transmission span, increases the process difficulty and implementation cost, and reduces the portability and flexibility of the pipetting device. In view of this technical problem, an embodiment of a separation mechanism different from the existing design is implemented to realize the automatic separation function of the tip 1; specifically:

[0075] Referring to Figures 11 to 13 As shown, the push rod 8 is internally provided with a column cavity 43 which is open only at the front end, the main body 4 is internally fixed with a guide rod 18 extending in the front-rear direction, and the rear end of the guide rod 18 is fixed with a second piston 44; the second piston 44 is located inside the column cavity 43 of the push rod 8, and the two are in sealed sliding fit, the guide rod 18 is hollow and in communication with the column cavity 43; a top ring 39 capable of moving forward and backward is sleeved on the joint 2, and the tip 1 is fixed after installation and located on the front side of the top ring 39; a piston cylinder 41 is fixed on the main body 4, the piston cylinder 41 is internally provided with a third piston 47 and a push spring 46 for driving the third piston 47 to move backward, and the third piston 47 is fixedly connected with the top ring 39 through a top rod 40; the inner cavity of the guide rod 18 is in communication with the piston cylinder 41 through a first gas path 48 and in communication with the atmosphere through a second gas path 45.

[0076] Based on the above design, in the normal pipetting operation, the second gas path 45 is kept in communication with the atmosphere, and during the forward and backward movement of the push rod 8, the interior of the push rod 8 is in communication with the atmosphere through the inner cavity of the guide rod 18 and the second gas path 45, so as not to drive the third piston 47 in the piston cylinder 41, that is, the position of the top ring 39 will not change; when the tip 1 is separated after the completion of the pipetting operation, the second gas path 45 is temporarily closed, and when the push rod 8 moves forward, the gas in the interior of the push rod 8 enters the interior of the piston cylinder 41 through the inner cavity of the guide rod 18 and the first gas path 48, and the third piston 47 drives the top ring 39 to move forward through the top rod 40, thereby driving the tip 1 to separate from the joint 2; when the push rod 8 moves backward, the top ring 39 and the third piston 47 will reset to the initial position; thereby realizing the automatic separation of the tip 1. Since it is not necessary to separately provide a button and a complex transmission mechanism on the main body 4 for the separation of the tip 1, it is helpful to simplify the overall structure of the pipetting device, make it more compact, flexible and convenient.

[0077] In further design, the first gas path 48 and the second gas path 45 can adopt a pipeline or a flow channel opened in the interior of the main body 4.

[0078] In further design, in order to facilitate the regulation of the communication state between the inner cavity of the guide rod 18 and the atmosphere, a ventilation valve with switch state regulation function can be arranged on the second air path 45, and the ventilation valve is a normally open type press valve, and the ventilation valve is fixedly connected with the main body 4 and the pressing part is located outside the main body 4.

[0079] In further design, the main body 4 is provided with a ventilation hole 42 at the front end, and the second air path 45 is communicated with the atmosphere through the ventilation hole 42; thus, when the suction head 1 is separated, the second air path 45 can be temporarily closed by pressing the ventilation hole 42 with fingers, which is convenient and easy to operate.

[0080] Although the embodiments of the present application have been shown and described, it is to be understood that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A pipetting device for cerebrospinal fluid detection, comprising a fixedly connected main body and a pipette; the front end of the pipette is provided with a connector, and the inside is provided with a first piston; characterized in that: The pipette device comprises a main body, a first piston, a sliding rod, a push rod, a spring, a suction volume setting rod, a synchronizing frame, a push-up piece and a locking piece. The fourth abutting part drives the push rod to move forward through the second abutting part during the process of the push-up piece being driven to rotate to the initial position by the elastic member, so as to restore the pipette device to the initial state.

2. The pipetting device for cerebrospinal fluid testing according to claim 1, characterized in that: The central axes of the pipette, the first piston, the sliding rod and the suction volume setting rod coincide.

3. The pipetting device for cerebrospinal fluid testing of claim 1, wherein: The main body is internally provided with a first guide groove extending in the front-rear direction, the middle-rear part of the sliding rod is in sliding fit with the first guide groove.

4. The pipetting device for cerebrospinal fluid testing of claim 1, wherein: The synchronizing frame is fixedly connected with the front end of the push rod, and is located in front of the transmission gear.

5. The pipetting device for cerebrospinal fluid testing of claim 1, wherein: The main body is internally provided with an internally threaded sleeve capable of rotating, the rear end of the internally threaded sleeve is provided with a knob, the knob is located at the rear side of the main body.

6. The pipetting device for cerebrospinal fluid testing of claim 5, wherein: The knob is provided with a pointer on one side, the rear end surface of the main body is provided with an annular scale, and the annular scale surrounds the outside of the knob. During one rotation of the internally threaded sleeve, the displacement of the suction volume setting rod is exactly one graduation value of the volume scale.

7. The pipetting device for cerebrospinal fluid testing of claim 5, wherein: The side wall of the inhalation amount setting rod is provided with a recessed area, and the volume scale is marked in the recessed area.

8. The pipetting device for cerebrospinal fluid testing of claim 1, wherein: The push rod is internally provided with a column cavity which is open only at the front end, the main body is internally fixed with a guide rod, the rear end of the guide rod is fixed with a second piston; the second piston is located in the column cavity of the push rod and is in sealed sliding fit, the guide rod is hollow and is in communication with the column cavity; a top ring is sleeved on the joint, the main body is fixed with a piston cylinder, the piston cylinder is internally provided with a third piston and a push spring, the third piston is fixedly connected with the top ring through the top rod; the inner cavity of the guide rod is in communication with the piston cylinder through a first gas path and is in communication with the atmosphere through a second gas path.

9. The pipetting device for cerebrospinal fluid testing of claim 8, wherein: An air vent valve is arranged on the second gas path; the air vent valve is a normally open type press valve, is fixed on the main body and the press part is located outside the main body.

10. The pipetting device for cerebrospinal fluid testing of claim 8, wherein: The main body is provided with an air vent hole at the front end, and the second gas path is in communication with the atmosphere through the air vent hole.

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