CN212615197U

CN212615197U - Cassette liquid transfer pump assembly

Info

Publication number: CN212615197U
Application number: CN202021236970.9U
Authority: CN
Inventors: 袁庆明
Original assignee: Shanghai 3D Medicines Co Ltd
Current assignee: Shanghai 3D Medicines Co Ltd
Priority date: 2020-06-29
Filing date: 2020-06-29
Publication date: 2021-02-26
Anticipated expiration: 2030-06-29

Abstract

The utility model discloses a cassette liquid-transfering pump assembly, which comprises a pump assembly main body, wherein the pump assembly main body is composed of a pump pipe, a spring, a push rod cover, a limit cover and a push rod, a piston cavity and a spring cavity are arranged in the pump pipe, the piston cavity is positioned at the front side of the spring cavity and coaxially communicated with the spring cavity, and the diameter of the piston cavity is smaller than that of the spring cavity; the foremost end of pump line is equipped with the mouthpiece that is linked together with the piston chamber, the utility model discloses a two 0 type circle structures, whole have better leakproofness, have effectively improved and have moved the liquid precision, and the lug possesses the function of direction, and the protrusion structure cooperation photoelectric sensor of lug can the feedback push rod the concrete position simultaneously, has improved the position precision.

Description

Cassette liquid transfer pump assembly

Technical Field

The utility model belongs to the technical field of the pipettor and specifically relates to a cassette moves liquid pump assembly.

Background

Existing closed cartridges typically include a pipetting system that includes a pump assembly, a movement assembly, and a pipetting head assembly. The sealing quality of the piston of the pump body directly influences the precision of liquid suction and discharge, thereby influencing the service performance of the instrument. At present, a sealing ring with standard specifications is generally installed on the outer circumferential surface of a piston, the compression ratio is 30% in the dynamic state, large compression ratio can obtain large contact pressure, however, excessive compression ratio can increase sliding friction force and permanent shape, and too small compression ratio can eliminate partial compression amount to cause leakage, so that the sealing effect is poor.

The existing pump assembly does not feed back the position of the push rod when sucking and releasing, and the sucking/releasing amount of liquid cannot be accurately controlled. In addition, the connection part of the push rod and the pipe is easy to loosen, so that liquid leakage is caused, and the liquid transferring precision is influenced.

SUMMERY OF THE UTILITY MODEL

The utility model discloses an it is not enough to overcome above-mentioned condition, aims at providing the technical scheme that can solve above-mentioned problem.

A cassette liquid transfer pump assembly comprises a pump assembly body, wherein the pump assembly body is composed of a pump pipe, a spring, a push rod cover, a limiting cover and a push rod, the pump pipe is of a stepped reducing structure, a piston cavity and a spring cavity are arranged in the pump pipe, the piston cavity is located at the front side of the spring cavity and coaxially communicated with the spring cavity, and the diameter of the piston cavity is smaller than that of the spring cavity; the foremost end of the pump pipe is provided with a nozzle communicated with the piston cavity, and the nozzle and the pump pipe form an integrated structure;

the push rod is of a long straight rod-shaped structure, wherein a push rod cover is fixed at the tail end of the push rod, and a convex bump is integrally formed on the outer side surface of the push rod cover;

the front end of the push rod is coaxially inserted into the piston cavity through the spring cavity; the push rod cover is arranged in the spring cavity, the inner side surface of the spring cavity is in sliding contact with the push rod cover, a linear guide groove communicated with the spring cavity is formed in the surface of the pump pipe, and the convex block is embedded into the linear guide groove in a sliding manner; at the moment, the convex block has a guiding function, and meanwhile, the convex structure of the convex block can feed back the specific position of the push rod by matching with the photoelectric sensor, so that the convex block has multiple functions;

the spring is arranged in the spring cavity, the spring is movably sleeved at the outer side position of the push rod, and two ends of the spring elastically abut against the push rod cover and a step surface at the joint position of the piston cavity and the spring cavity respectively; the spring is used for providing power for the push rod to move forwards and then reset;

the rear end opening position of the pump pipe is sealed by a limiting cover, the limiting cover is fixedly connected with the pump pipe by a screw, a through opening is arranged at the center of the limiting cover, and the opening is used for enabling an external driving structure to contact with and apply thrust to a push rod cover, so that the movement of the whole push rod is realized; the opening and the push rod cover are coaxially arranged, and the size of the opening is smaller than that of the push rod cover;

a push rod head is integrally formed at the front end of the push rod, a first convex part in an outward diffusion petal shape is integrally formed at the head end position of the push rod head, a second convex part in an outward bulge shape is integrally formed at the middle position of the push rod head, and the second convex part and the first convex part are arranged at intervals; based on the petal structure of the first bulge and the gap structure between the second bulge and the first bulge, the contact area between the sealing ring and the push rod head can be increased, meanwhile, the relative sliding condition between the sealing ring and the push rod head can be reduced through the concave-convex structure, the push rod head is injection-molded with a double-O-shaped sealing ring, and the sealing ring is integrally wrapped at the outer position of the push rod head; a first O-shaped ring and a second O-shaped ring which protrude outwards are coaxially and integrally formed on the outer surface of the sealing ring, the first O-shaped ring and the second O-shaped ring are arranged at intervals, and the first O-shaped ring and the second O-shaped ring are elastically and hermetically abutted against the inner wall of the piston cavity; and the diameter of the second O-shaped ring is larger than that of the first O-shaped ring.

Set up a plurality of sunken sprue holes on the surface of the second bulge of putter head, the sprue hole is used for putter head's injection moulding, the partial structure of sealing washer is absorbed in the setting of sprue hole simultaneously, this structure has improved the area of contact between sealing washer and the putter head, thereby make and connect more stably, sunken sprue hole is used for weakening the lateral wall indenture that the putter head produced when moulding plastics simultaneously, thereby weaken structural stress, further reinforcing and the stability of being connected of sealing washer, with this reach better sealed effect, can avoid double-seal ring axial slip through this structure, and also can guarantee to have better resistance to deformation's ability in pump operation process, guarantee the precision of imbibition simultaneously.

As a further aspect of the present invention: first bulge comprises a plurality of petal bodies that are radial setting and equal contained angle interval and set up, and the clearance between the petal body is used for improving area of contact and the contact form with the sealing washer to improve joint strength.

The utility model has the advantages that: the utility model discloses a two 0 type circle structures, whole better leakproofness has, can avoid the double containment circle axial slip to also can guarantee that there is better resistance to deformation ability in pump operation process to improve the precision of imbibition, the lug possesses the function of direction, and the protrusion structure cooperation photoelectric sensor of lug can feed back the concrete position of push rod simultaneously, through this structure, the precision of assurance imbibition that can be better.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without inventive exercise.

FIG. 1 is a schematic structural view of the present invention;

fig. 2 is an exploded view of the present invention.

Fig. 3 is a front view of the present invention.

Fig. 4 is a view a-a of fig. 3.

Fig. 5 is an enlarged view at C in fig. 4.

Fig. 6 is a perspective view of the putter head.

In the figure: 1-pump tube, 2-spring, 3-push rod cover, 4-lug, 5-limit cover, 6-screw, 7-push rod, 8-push rod head, 9-sealing ring, 10-first O-shaped ring, 11-second O-shaped ring, 12-sprue hole, 13-first bulge, 14-second bulge and 15-petal body.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

Referring to fig. 1 to 6, in an embodiment of the present invention, a cassette liquid-transfering pump assembly includes a pump assembly main body, the pump assembly main body is composed of a pump tube 1, a spring 2, a push rod cover 3, a limit cover 5 and a push rod 7, wherein the pump tube 1 is of a stepped reducing structure, a piston cavity and a spring cavity are arranged in the pump tube 1, the piston cavity is located at a front side position of the spring cavity and coaxially communicated with the spring cavity, and a diameter of the piston cavity is smaller than that of the spring cavity; the foremost end of the pump pipe 1 is provided with a nozzle communicated with the piston cavity, and the nozzle and the pump pipe 1 form an integrated structure;

the push rod 7 is of a long straight rod-shaped structure, wherein the push rod cover 3 is fixed at the tail end of the push rod 7, and a convex bump 4 is integrally formed on the outer side surface of the push rod cover 3;

the front end of the push rod 7 is coaxially inserted into the piston cavity through the spring cavity; the push rod cover 3 is arranged in the spring cavity, the inner side surface of the spring cavity is in sliding contact with the push rod cover 3, a linear guide groove communicated with the spring cavity is formed in the surface of the pump pipe 1, and the convex block 4 is embedded into the linear guide groove in a sliding manner; at the moment, the bump 4 has a guiding function, and meanwhile, the protruding structure of the bump 4 can feed back the specific position of the push rod 7 by matching with the photoelectric sensor, so that the bump 4 has multiple functions;

the spring 2 is arranged in the spring cavity, the spring 2 is movably sleeved at the outer side position of the push rod 7, and two ends of the spring 2 elastically abut against the push rod cover 3 and a step surface at the joint position of the piston cavity and the spring cavity respectively; the spring 2 is used for providing power for the push rod 7 to reset after moving forwards;

the rear end opening position of the pump pipe 1 is sealed by a limiting cover 5, the limiting cover 5 is fixedly connected with the pump pipe 1 through a screw 6, a through-shaped opening is formed in the central position of the limiting cover 5, and the opening is used for enabling an external driving structure to contact the push rod cover 3 and apply thrust to the push rod cover 3, so that the whole push rod 7 can move; the opening and the push rod cover 3 are coaxially arranged, and the size of the opening is smaller than that of the push rod cover 3;

a push rod head 8 is integrally formed at the front end of the push rod 7, a first convex part 13 in an outward diffusion petal shape is integrally formed at the head end position of the push rod head 8, a second convex part 14 in an outward bulge shape is integrally formed at the middle position of the push rod head 8, and the second convex part 14 and the first convex part 13 are arranged at intervals; based on the petal structure of the first protruding part 13 and the gap structure between the second protruding part 14 and the first protruding part 13, the contact area between the sealing ring and the push rod head can be increased, meanwhile, the relative sliding condition between the sealing ring and the push rod head can be reduced by the concave-convex structure, the push rod head 8 is injection molded with a double-O-shaped sealing ring 9, and the double-O-shaped sealing ring 9 is integrally molded and wrapped at the outer position of the push rod head 8; the outer surface of the double-O-shaped sealing ring 9 is coaxially and integrally provided with a first O-shaped ring 10 and a second O-shaped ring 11 which protrude outwards, the first O-shaped ring 10 and the second O-shaped ring 11 are arranged at intervals, and the first O-shaped ring 10 and the second O-shaped ring 11 are elastically and hermetically abutted against the inner wall of the piston cavity. Because the double-O-shaped sealing ring 9 is formed by injection molding, in order to facilitate demoulding, the pump pipe 1 which is in close contact with the double-O-shaped sealing ring 9 has a reverse mould angle of 0.19 degrees, and the diameter of the second O-shaped ring is slightly larger than that of the first O-shaped ring.

The first protruding portion 13 is composed of a plurality of petal bodies 15 which are arranged in the radial direction and are arranged at equal included angle intervals, and gaps among the petal bodies 15 are used for improving the contact area and the contact form with the sealing ring 9, so that the connection strength is improved.

Set up a plurality of sunken sprue holes 12 on the surface of the second bulge 14 of putter head 8, sprue holes 12 is used for putter head 8's injection moulding, the setting up of sprue holes 12 makes the partial structure of sealing washer 9 sink into simultaneously, this structure has improved the area of contact between sealing washer 9 and the putter head 8, thereby in the increase friction, prevent sliding between sealing washer and the putter head, sunken sprue holes 12 is used for weakening the lateral wall indenture that putter head 8 produced when moulding plastics simultaneously, thereby weaken structural stress, further reinforcing and sealing washer 9's stability of being connected, reach better sealed effect with this.

The maximum outer diameter of the first O-ring 10 and the second O-ring 11 is 3.90 mm;

the maximum aperture of the first O-shaped ring 10 and the second O-shaped ring 11 is 3.57mm, the minimum aperture is 3.56mm, the reverse mould angle is 0.19 degrees, and the minimum aperture is 3.43 mm;

the maximum compression ratio (3.90-3.43)/3.90 of the first O-ring 10 and the second O-ring 11 is 12%;

the minimum compression ratio (3.90-3.57)/3.90 of the first O-ring 10 and the second O-ring 11 is 8%.

It is obvious to a person skilled in the art that the invention is not restricted to details of the above-described exemplary embodiments, but that it can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Claims

1. A cassette liquid transfer pump assembly comprises a pump assembly body, wherein the pump assembly body is composed of a pump tube (1), a spring (2), a push rod cover (3), a limiting cover (5) and a push rod (7), a piston cavity and a spring cavity are arranged in the pump tube (1), the piston cavity is located at the front side of the spring cavity and coaxially communicated with the spring cavity, and the diameter of the piston cavity is smaller than that of the spring cavity; the foremost end of the pump pipe (1) is provided with a nozzle communicated with the piston cavity;

the push rod cover (3) is fixed at the tail end of the push rod (7), and a convex bump (4) is integrally formed on the outer side surface of the push rod cover (3);

the front end of the push rod (7) is coaxially inserted into the piston cavity through the spring cavity; the push rod cover (3) is arranged in the spring cavity, and the inner side surface of the spring cavity is in sliding contact with the push rod cover (3);

the spring (2) is arranged in the spring cavity, and the spring (2) is movably sleeved at the outer side position of the push rod (7);

the novel push rod is characterized in that a push rod head (8) is integrally formed at the front end of a push rod (7), a first protruding part (13) and a second protruding part (14) are integrally formed on the push rod head (8), and the first protruding part (13) and the second protruding part (14) are arranged at intervals;

a sealing ring (9) is formed on the push rod head (8) in an injection molding mode, and the sealing ring (9) is integrally wrapped outside the push rod head (8); a first O-shaped ring (10) and a second O-shaped ring (11) which protrude outwards are coaxially and integrally formed on the outer surface of the sealing ring (9), the first O-shaped ring (10) and the second O-shaped ring (11) are arranged at intervals, and the diameter of the second O-shaped ring (11) is larger than that of the first O-shaped ring (10).

2. A cartridge pipette pump assembly according to claim 1, characterized in that the first projection (13) is constituted by a plurality of petal bodies (15) arranged radially and at equal angular intervals.

3. A cartridge pipette pump assembly according to claim 1, wherein the outer surface of the second projection (14) of the pusher head (8) is provided with a plurality of recessed gate holes (12).

4. A cartridge pipette pump assembly according to claim 1, characterized in that the maximum compression ratio of the first O-ring (10) to the second O-ring (11) is 12%; the minimum compression ratio of the first O-ring (10) to the second O-ring (11) is 8%.

5. A cartridge pipette pump assembly according to claim 1, characterized in that the nozzle is of one-piece construction with the pump tube (1).

6. A cartridge pipetting pump assembly according to claim 1, characterised in that the pusher (7) is of elongate straight rod-like construction.

7. A cassette pipetting pump assembly according to claim 1 wherein the ends of the spring (2) resiliently abut against the plunger cover (3) and the step surface at the location where the piston chamber meets the spring chamber, respectively.

8. A cassette-pipetting pump assembly according to claim 1, wherein the pump tube (1) has a linear guide groove in the surface communicating with the spring chamber, into which the projection (4) is slidably inserted.

9. A cartridge pipette pump assembly according to claim 1, wherein the pump tube (1) is of stepped reducing construction.