Pipette clamping mechanism

Abstract

The present invention relates to the field of laboratory automation technology, and discloses a pipette clamping mechanism, comprising a gun body, a gun head and a ferrule, wherein the gun head is arranged above the gun body, the gun head is hollow, an annular groove is arranged on the outer diameter, the top of the gun head is tapered and chamfered, the ferrule comprises a connector, a spacer and a gun return sleeve, the upper end of the connector is used to connect to a driving component, the lower end is connected to the spacer, a plurality of steel balls are arranged below the spacer along the outer diameter, a liner is sleeved inside the spacer, the lower end of the liner forms an inverted conical hole, a first pressure spring is arranged inside the inner surface of the liner, a gun return sleeve is sleeved outside the spacer, the lower end of the gun return sleeve has a stepped hole, the stepped transition section is a tapered ring, a second pressure spring is arranged above the stepped hole and at the head position of the spacer, and a retaining ring is arranged on the spacer below the gun return sleeve. The present invention cooperates the steel balls with the liner and the gun head, so that the position of the steel balls between the liner and the gun head can be changed by the gun return sleeve, thereby achieving rapid gun replacement.

Description

Technical Field

[0001] The present invention relates to the technical field of laboratory automation, and in particular to a pipette clamping mechanism. Background Art

[0002] In liquid handling applications within biochemical automation equipment, eight rows of guns simultaneously inject liquids into well plates and containers through multiple channels. The automated control system for the guns within the automation system requires mechanical replacement of the guns.

[0003] For example, the Chinese patent "Liquid Injection Gun" (application number: 2022219903753) discloses a clamping structure that uses the clamping columns on both sides of the gun body and the grooves on both sides of the gun changing seat to achieve hard top pressure and lifting, thereby disengaging and clamping the gun and the gun changing head.

[0004] In actual applications, this method often leads to problems such as difficult installation and easy damage to the gun holder. The gun head and the gun body are only connected by a clamp, which is prone to noise and gun head vibration. Summary of the Invention

[0005] The purpose of the present invention is to solve the above problems and provide a pipette clamping mechanism, which cooperates with the liner and the gun head through the steel ball, so that the position of the steel ball between the liner and the gun head can be changed by withdrawing the gun sleeve, thereby realizing quick gun replacement.

[0006] The technical solution adopted by the present invention is:

[0007] The top of the gun is connected with the driving part, and the lower end is connected with the spacer. A plurality of steel ball holes are provided along the outer diameter of the spacer, and steel balls are provided in the gaps in the steel ball holes. A liner is sleeved on the inside of the spacer, and an inverted conical hole is formed at the lower end of the liner, and the inverted conical hole matches the conical chamfer of the top of the gun head. The outer surface of the liner and the inner surface of the spacer form a limiting step. A first pressure spring is provided on the inner surface of the liner, and a gun return sleeve is sleeved on the outside of the spacer. The lower end of the gun return sleeve has a stepped hole, and the stepped transition section is a tapered ring. A second pressure spring is provided above the stepped hole and at the head position of the spacer, and a retaining ring is provided on the spacer below the gun return sleeve.

[0008] Furthermore, the pipette gun mounting mechanism also includes a gun changing rack, which is a frame-shaped structure with a gun body placement space in the middle. A card slot is provided on the upper plane of the gun changing rack, and the card slot is used to fix the gun body. A slide groove is provided on one side of the gun changing rack, and a gun withdrawal top block is provided in the slide groove. A slope is provided on the inner side of the gun withdrawal top block, and a push rod is provided on the outside. The gun withdrawal top block is provided in the slide groove by a thrust spring, and the position of the push rod is such that when the gun body is pressed down, the push rod cooperates with the lower surface of the gun withdrawal sleeve.

[0009] Furthermore, the number of the steel ball holes is 4-8.

[0010] Furthermore, the annular groove of the gun head is a semicircular annular groove, and the diameter thereof matches the diameter of the steel ball.

[0011] Furthermore, the cone angle of the inverted tapered hole of the liner is 15-20°.

[0012] Furthermore, the cone angle of the stepped transition section cone ring of the gun retracting sleeve is 45°.

[0013] Furthermore, the slopes of the gun-retracting top block are arranged at both ends of the gun-retracting top block, and the front of the slopes is a vertical plane.

[0014] Furthermore, the thrust springs are arranged at both ends of the gun retracting top block, and the thrust springs are arranged through a guide shaft.

[0015] Furthermore, the four side surfaces of the gun changing rack are hollowed out and fixed at the bottom by a fastener.

[0016] Furthermore, after the gun body is retracted, the retracting top block is flush with the top surface of the gun body.

[0017] The beneficial effects of the present invention are:

[0018] (1) The steel ball is clamped between the liner and the gun head, which is subjected to large force and firmly realizes the clamping of the gun body;

[0019] (2) When removing the holster, a small lifting force is required to quickly remove the gun body;

[0020] (3) The structure is ingenious, the card assembly is stable, and there is no noise or vibration. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Attachment Figure 1 This is a schematic diagram of the structure in which the septum is clamped on the pipette;

[0022] Attachment Figure 2 It is a schematic diagram of the cross-sectional structure after the card is installed;

[0023] Attachment Figure 3 It is a schematic diagram of the cross-sectional structure from another angle;

[0024] Attachment Figure 4 This is a schematic diagram of the structure of the pipette gun fitted on the gun changing rack;

[0025] Attachment Figure 5 It is a partial enlarged view of the fixed cooperation between the gun holder and the pipette gun.

[0026] The reference numerals in the accompanying drawings are:

[0027] 1. Gun body; 2. Gun head;

[0028] 3. Ferrule; 4. Connector;

[0029] 5. Spacer; 6. Holster removal;

[0030] 7. Piston rod; 8. Ring groove;

[0031] 9.Steel ball hole; 10.Steel ball;

[0032] 11. Liner; 12. First pressure spring;

[0033] 13. Second pressure spring; 14. Retaining ring;

[0034] 15. Positioning head; 16. Positioning hole;

[0035] 17. Replace the gun mount; 18. Card slot;

[0036] 19. Slide; 20. Gun ejector block. Implementation Method

[0037] The specific implementation of the pipette clamping mechanism of the present invention will be described in detail below with reference to the accompanying drawings.

[0038] See attached Figure 1 The pipette clamping mechanism includes a pipette body 1, a pipette tip 2, and a ferrule 3. The ferrule 3 includes a connector 4, a spacer 5, and a retractor 6. The upper end of the connector 4 is connected to a drive component mounted on a mechanical or robotic arm. The drive component drives the piston rod 7 of the pipette via a motor-driven push rod 21, which raises and lowers the piston rod 7, completing the pipette's aspiration and injection operations. The lower end of the connector 4 is connected to a spacer 5, through which the ferrule 3 connects and disconnects from the pipette body 1.

[0039] See attached Figure 2 、 3 The gun head 2 is arranged above the gun body 1. The gun head 2 is hollow and has an annular groove 8 on the outer diameter. The top is a conical chamfer. The depth of the annular groove 8 is a semicircular depth annular groove.

[0040] Several steel ball holes 9 are provided along the outer diameter of the spacer 5. Steel balls 10 are positioned in the gaps between these holes. These holes are evenly distributed around the circumference of the spacer 5. The wall thickness of the spacer 5 should be at least half the diameter of the steel balls 10 to allow them to pass freely. The number of steel balls 10 is preferably 4-8. The diameter of the annular groove 8 matches that of the steel balls 10. When the steel balls 10 fall into the annular groove 8, a clearance fit is achieved for optimal fit.

[0041] The liner 11 is sleeved inside the spacer 5, and the lower end of the liner 11 forms an inverted tapered hole, which matches the conical chamfer at the top of the gun head 2. The angle between the inverted tapered hole and the chamfer at the top of the gun head 2 is preferably 15-20 degrees.

[0042] The outer surface of the liner 11 forms a limiting step with the inner surface of the spacer 5. A first pressure spring 12 is disposed within the inner surface of the liner 11. When the top of the gun head 2 is lifted upward, the conical chamfer cooperates with the inverted conical hole, and the gun head 2 lifts the liner 11 upward. Under the elastic force of the first pressure spring 12, the liner 11 generates a downward pressure, maintaining its engagement with the gun head 2.

[0043] The outer side of the spacer 5 is sleeved with a gun withdrawal sleeve 6, the lower end of the gun withdrawal sleeve 6 has a stepped hole, and the stepped transition section is a cone ring. The cone ring has two sections, the upper section has a relatively gentle slope, and the cone angle of the lower section can be 45°.

[0044] A second pressure spring 13 is provided above the stepped hole and at the head of the spacer 5, and a retaining ring 14 is provided on the spacer 5 below the gun withdrawal sleeve 6. The gun withdrawal sleeve 6 is restricted on the spacer 5 by the retaining ring 14, and due to the pressure of the second pressure spring 13, the gun withdrawal sleeve 6 tends to move downward.

[0045] A positioning head 15 is provided at the bottom of the spacer 5, and a positioning hole 16 is provided on the upper surface of the gun body 1. The positioning holes 16 are located on both sides of the gun head 2. When the spacer 5 is pressed down, the positioning head 15 cooperates with the positioning holes 16 for positioning to prevent relative rotation between the spacer 5 and the gun body 1 and affect the position of the gun body 1.

[0046] See attached Figure 4 、 5 The gun rack 17 is located in a fixed position on the automated equipment and is used to store volley guns or other mobile equipment. The gun rack 17 is a frame-shaped structure with a central space for the gun body 1. A slot 18 is provided on the upper surface of the gun rack 17 to secure the gun body 1. The upper side edge of the gun body 1 cooperates with the slot 18 to support the gun body 1.

[0047] A slide groove 19 is provided on one side of the gun changing frame 17, a gun withdrawing top block 20 is provided in the slide groove 19, a slope is provided on the inner side of the gun withdrawing top block 20, and a push rod 21 is provided on the outside. The gun withdrawing top block 20 is provided in the slide groove 19 by a thrust spring, and the position of the push rod 21 is such that when the gun body 1 is pressed down, the push rod 21 cooperates with the lower surface of the gun withdrawing sleeve 6.

[0048] The slopes of the gun-retracting top block 20 are set at both ends of the gun-retracting top block 20, and the front of the slope is a vertical plane for fixing the pipette. Thrust springs are set at both ends of the gun-retracting top block 20, and thrust springs (not shown in the figure) are set through guide shafts.

[0049] The specific card installation and removal process is as follows:

[0050] The gun body 1 is pre-set and fixed on the gun changing frame 17. The four sides of the gun changing frame 17 are hollowed out and fixed at the bottom by a fixing member. The ferrule 3 is installed on the driving component of the robotic arm. The driving component is moved by the robotic arm to the top of the gun body 1. When pressed down, the conical chamfer of the gun head 2 lifts the inverted conical hole of the liner 11, causing the liner 11 to rise. The gun retraction sleeve 6 outside the spacer 5 is squeezed inward due to the presence of the cone ring below and the pressure of the second pressure spring 13, so that the steel ball 10 in the steel ball hole 9 below the spacer 5 is squeezed inward. When the liner 11 rises, the steel ball hole 9 of the spacer 5 is opened, and the steel ball 10 is squeezed inward from the steel ball hole 9 and falls into the annular groove 8 of the gun head 2. At this time, half of the steel ball 10 is stuck in the annular groove 8, and the other half still falls into the steel ball hole 9 of the spacer 5. A radial cutting force is generated between the two, which makes the gun head 2 and the ferrule 3 firmly stuck, realizing the clamping of the pipette gun. After being clamped, the driving component passes through the through hole in the middle of the clamping sleeve 3 through the driving shaft and cooperates with the piston rod 7 inside the gun body 1 to perform operations such as liquid suction and liquid injection.

[0051] After completing the pipetting action and replacing the gun body 1, the driving component moves the pipette liquid to the top of the gun changing frame 17 and sends the gun body 1 downward into the gun changing frame 17. At this time, the gun withdrawal top block 20 of the gun changing frame 17 is pressed down by the side of the gun body 1, and the gun withdrawal top block 20 is pushed outward. As the gun body 1 descends, the push rod 21 of the gun withdrawal top block 20 just supports the lower surface of the gun withdrawal sleeve 6. The gun withdrawal sleeve 6 is subjected to an upward pushing force, and the second pressure spring 13 is compressed. After the gun withdrawal sleeve 6 moves upward, the cone ring on the gun withdrawal sleeve 6 is located at the steel ball hole 9 position of the spacer 5. The steel ball 10 is subjected to an upward lifting force and disengages from the ring groove 8 of the gun head 2. At this time, there is no shear force of the steel ball 10 between the spacer 5 and the gun head 2, and the two are disengaged, completing the disengagement of the pipette. At this time, the gun body 1 is just pressed and fixed on the gun changing frame 17 by the side of the gun withdrawing top block 20 , and the gun withdrawing top block 20 is flush with the top surface of the gun body 1 .

[0052] At this time, the gun body 1 on the gun rack 17 is waiting to be clamped for the second time. During the clamping, due to the outward movement of the gun withdrawal top block 20, the push rod 21 thereon is located outside the gun withdrawal sleeve 6 and does not generate a pushing force on the gun withdrawal sleeve 6, thereby not affecting the clamping.

[0053] The above are only preferred embodiments of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and modifications without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A pipette clamping mechanism, characterized by: The invention comprises a gun body, a gun head and a ferrule, wherein the gun head is arranged above the gun body, the gun head is hollow, a ring groove is arranged on the outer diameter, the top of the gun head is a conical chamfer, the ferrule comprises a connecting piece, a spacer and a gun return sleeve, the upper end of the connecting piece is used to connect the driving component, and the lower end is connected to the spacer, a plurality of steel ball holes are arranged along the outer diameter below the spacer, steel balls are arranged in the gaps in the steel ball holes, a liner is sleeved inside the spacer, an inverted conical hole is formed at the lower end of the liner, the inverted conical hole matches the conical chamfer at the top of the gun head, the outer surface of the liner and the inner surface of the spacer form a limiting step, a first pressure spring is arranged inside the inner surface of the liner, a gun return sleeve is sleeved outside the spacer, and the The lower end of the gun withdrawal sleeve is provided with a stepped hole, and the stepped transition section is a conical ring. A second pressure spring is arranged above the stepped hole and at the head position of the spacer sleeve, and a retaining ring is arranged on the spacer sleeve below the gun withdrawal sleeve. The pipette gun mounting mechanism also includes a gun changing rack, and the gun changing rack is a frame-shaped structure with a gun body placement space in the middle. A card slot is arranged on the upper plane of the gun changing rack, and the card slot is used to fix the gun body. A slide groove is arranged on one side of the gun changing rack, and a gun withdrawal top block is arranged in the slide groove. A slope is arranged on the inner side of the gun withdrawal top block, and a push rod is arranged on the outside. The gun withdrawal top block is arranged in the slide groove by a thrust spring, and the position of the push rod makes the push rod cooperate with the lower surface of the gun withdrawal sleeve when the gun body is pressed down.

2. The pipette clamping mechanism according to claim 1, characterized in that: The number of the steel ball holes is 4-8.

3. The pipette clamping mechanism according to claim 1, characterized in that: The annular groove of the gun head is a semicircular annular groove, and the diameter thereof matches the diameter of the steel ball.

4. The pipette clamping mechanism according to claim 2 or 3, characterized in that: The cone angle of the inverted tapered hole of the liner is 15-20 degrees.

5. The pipette clamping mechanism according to claim 2 or 3, characterized in that: The cone angle of the stepped transition section cone ring of the gun retracting sleeve is 45°.

6. The pipette clamping mechanism according to claim 1, characterized in that: The slopes of the gun-retracting top block are arranged at both ends of the gun-retracting top block, and the front of the slopes is a vertical plane.

7. The pipette clamping mechanism according to claim 1, characterized in that: The thrust springs are arranged at both ends of the gun retracting top block, and the thrust springs are arranged through a guide shaft.

8. The pipette clamping mechanism according to claim 1, characterized in that: The four side surfaces of the gun changing rack are hollowed out, and the bottom is fixed by a fastener.

9. The pipette clamping mechanism according to any one of claims 6 to 8, characterized in that: After the gun body is retracted, the retracting top block is flush with the top surface of the gun body.

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