Pipette device

Abstract

The present invention provides a pipetting device that can achieve a stable and normal fit without inserting the nozzle cone into the pipette tip more than necessary. [Solution] The nozzle cone 2 is provided with a stopper projection 22a that abuts against the rear end of the pipette tip 4 when the fitting portion 23 is fitted to the pipette tip 4 to its normal fitting length, and a cone-side engaging projection 23a is provided at the tip of the nozzle cone 2 so as to engage with a tip-side engaging recess 41 provided on the inside of the pipette tip 4.

Description

Technical Field

[0001] The present invention relates to a pipette device.

Background Art

[0002] As an instrument mainly used for measuring a small amount of liquid (fluid) in laboratories and testing rooms, a pipette device in which a pipette tip is detachably provided on a nozzle cone (also referred to as a "tip cone") is used (see Patent Document 1). That is, as shown in FIGS. 5 and 6, this pipette device includes a pipette device main body 100 and a replaceable pipette tip 400.

[0003] The pipette device main body 100 includes a nozzle cone 200 and an ejector 300. The nozzle cone 200 is inserted until it is determined that the tip end portion 210 thereof cannot be inserted any further into the rear end portion of the pipette tip 400 as shown in FIG. 6, so as to hold the pipette tip 400 in a fitted state.

[0004] The pipette tip 400 fitted to the tip portion of the nozzle cone 200 as described above is sucked and exhausted through the vent hole 220 at the tip of the nozzle cone 200 when a push button (not shown) of the pipette device main body 100 is operated, so that a desired amount of liquid can be sucked, measured and discharged from the tip of the pipette tip 400. When an ejector button (not shown) of the pipette device main body 100 is pressed, the ejector 300 slides in the direction indicated by the arrow in FIG. 6, and as shown by the two-dot chain line in FIG. 6, the tip of the ejector 300 abuts against the rear end of the pipette tip 400, and the pipette tip 400 can be pressed so as to be detached from the nozzle cone 200 while maintaining the abutting state.

Prior Art Literature

Patent Literature

[0005] [Patent Document 1] Japanese Patent Publication No. 2000-107613 [Overview of the project] [Problems that the invention aims to solve]

[0006] By the way, with conventional pipetting devices, it is difficult for the user of the pipetting device to clearly determine whether or not the pipette tip 400 has been properly fitted into the nozzle cone 200. Therefore, users tend to apply more force than necessary to press the nozzle cone 200 into the pipette tip 400. Therefore, excessive force must be applied to the ejector 300 to detach the pipette tip 400, which places a significant burden on the repetitive task of pipetting.

[0007] In view of the above circumstances, the present invention aims to provide a pipette device that can achieve a stable and normal fitting state without inserting the nozzle cone into the pipette tip more than necessary. [Means for solving the problem]

[0008] The pipette device of the present invention includes a pipette tip and the rear end of the pipette tip. Insertion The fitting part to be fitted is at the tip Furthermore, the rear end of this fitting portion is equipped with an ejector slide portion that expands in a stepped manner from the rear end of the fitting portion and has a stopper projection formed on the side end of the fitting portion. A nozzle cone, and a mechanism that allows this nozzle cone to slide in the axial direction. The nozzle A pipette device comprising a pipette device body having an ejector fitted onto a cone, wherein the fitting portion of the nozzle cone is fitted onto the rear end of the pipette tip, and the ejector slides toward the tip side of the nozzle cone to press against the rear end of the pipette tip, thereby allowing the pipette tip to be detached, The pipette tip has a tip-side tapered cylindrical portion at its rear end, the inner wall of which gradually narrows in diameter towards the tip, and a ring-shaped tip-side engaging recess is provided in a part of this tip-side tapered cylindrical portion, recessed from the wall surface of the tip-side tapered cylindrical portion. The nozzle cone fitting portion has a fitting portion body that is substantially frustoconical in shape, with a tapered outer wall surface that gradually narrows in diameter towards the tip, fitting into the tip-side tapered cylindrical portion, and a cone-side engaging projection that protrudes in a ring shape outward from the fitting portion body at the tip of the fitting portion body. The cone-side engaging projection is designed to elastically deform the inner wall surface of the rear end of the pipette tip so that it bends outward as the fitting portion is inserted into the pipette tip, and when it reaches a position where the stopper projection contacts the pipette tip, it fits into the tip-side engaging recess. It is characterized by the following.

[0009] In the present invention, the stopper protrusions may be provided continuously in the circumferential direction of the nozzle cone, or they may be provided intermittently in a radial pattern.

[0010] The pipette device of the present invention is not particularly limited, The tip-side engaging recess is formed as a groove with a substantially arc-shaped cross-section, and the cone-side engaging projection follows the cross-sectional shape of the tip-side engaging recess, gradually decreasing in diameter towards the tip of the fitting portion, and is formed as a substantially quarter-circular arc shape following the cross-sectional shape of the tip-side engaging recess. It is preferable to have a configuration that allows for this. In other words, the stopper protrusion is received by the rear end of the pipette tip, and at the same time, the tip-side engagement recess is also present. department and , cone-side engaging protrusion The department The engagement and click sensation clearly indicate that the nozzle cone has properly seated with the pipette tip. [Effects of the Invention]

[0012] The pipette device of the present invention includes a pipette tip and the rear end of the pipette tip. Insertion The fitting part to be fitted is at the tip Furthermore, the rear end of this fitting portion is equipped with an ejector slide portion that expands in a stepped manner from the rear end of the fitting portion and has a stopper projection formed on the side end of the fitting portion. A nozzle cone, and a mechanism that allows this nozzle cone to slide in the axial direction. The nozzle A pipette device comprising a pipette device body having an ejector fitted onto a cone, wherein the fitting portion of the nozzle cone is fitted onto the rear end of the pipette tip, and the ejector slides toward the tip side of the nozzle cone to press against the rear end of the pipette tip, thereby allowing the pipette tip to be detached, The pipette tip has a tip-side tapered cylindrical portion at its rear end, the inner wall of which gradually narrows in diameter towards the tip, and a ring-shaped tip-side engaging recess is provided in a part of this tip-side tapered cylindrical portion, recessed from the wall surface of the tip-side tapered cylindrical portion. The nozzle cone fitting portion has a fitting portion body that is substantially frustoconical in shape, with a tapered outer wall surface that gradually narrows in diameter towards the tip, fitting into the tip-side tapered cylindrical portion, and a cone-side engaging projection that protrudes in a ring shape outward from the fitting portion body at the tip of the fitting portion body. The cone-side engaging projection is designed to elastically deform the inner wall surface of the rear end of the pipette tip so that it bends outward as the fitting portion is inserted into the pipette tip, and when it reaches a position where the stopper projection contacts the pipette tip, it fits into the tip-side engaging recess. Therefore, it can reduce strain on the wrists caused by repetitive tasks and improve work efficiency. and, The ring-shaped undercut portion of a conventional pipette tip can be used as the tip-side engagement recess, and since only the shape of the nozzle cone of the conventional pipette device needs to be changed, the pipette device of the present invention can be manufactured without incurring significant costs. [Brief explanation of the drawing]

[0013] [Figure 1] This is a front view showing one embodiment of the pipette device of the present invention. [Figure 2]It is a diagram illustrating the step of attaching a pipette tip to the nozzle cone of the pipette apparatus in FIG. 1, wherein (a) of the same diagram shows the state at the start of attachment, (b) of the same diagram shows the state in the middle of attachment, and (c) of the same diagram shows the state after completion of attachment. [Figure 3] It is a diagram illustrating the step of detaching a pipette tip of the pipette apparatus in FIG. 1. [Figure 4] It is a half cross-sectional view of a tip holder of the pipette apparatus in FIG. 1. [Figure 5] It is a diagram showing the state before a pipette tip is attached to a nozzle cone of a conventional pipette apparatus. [Figure 6] It is a diagram showing the state where a pipette tip is attached to a nozzle cone of a conventional pipette apparatus. DESCRIPTION OF EMBODIMENTS

[0014] Hereinafter, the present invention will be described in detail with reference to the drawings showing embodiments thereof. FIG. 1 shows one embodiment of the pipette apparatus of the present invention.

[0015] As shown in FIG. 1, this pipette apparatus A comprises a pipette apparatus main body 1 and a pipette tip 4. The pipette apparatus main body 1 comprises a nozzle cone 2, a push button 11, an ejector 3, and an ejector operating portion 12.

[0016] As shown in Figures 2 and 3, the pipette tip 4 has a tip-side tapered cylindrical portion 40 at its rear end. The tip-side tapered cylinder portion 40 gradually decreases in diameter towards the tip of the pipette tip 4 and is provided with a tip-side engaging recess 41 that is recessed in a substantially arc shape from the wall surface of the tip-side tapered cylinder portion. As shown in FIG. 4, the nozzle cone 2 comprises a head portion 21, an ejector slide portion 22, and a fitting portion 23, and has a bottomed cylindrical shape with a vent hole 24 formed at the tip end. As shown in Figures 2 and 3, the ejector slide portion 22 is fitted with the ejector 3 (described later) so that it can slide freely. Its inner diameter is larger than the inner diameter of the ejector receiving surface 42 provided at the rear end (upper end during use) of the pipette tip 4 (described later), and smaller than the outer diameter of the ejector receiving surface 42. Its lower end surface serves as a stopper projection 22a.

[0017] The fitting portion 23 is As shown in Figures 2 and 3, the fitting portion includes a main body 23b and a cone-side engaging projection 23a. As shown in Figure 2(c), the fitting portion body 23b has the same taper as the tip-side tapered cylindrical portion 40, and its outer surface gradually decreases in diameter towards the tip. The cone-side engaging projection 23a is located at the tip of the fitting body 23b and is provided to protrude in a ring shape in the outer circumference direction of the fitting body 23b, The surrounding surface Fitting part body 23b The diameter gradually widens towards the tip, and its cross-section is the tip-side engagement recess. 41 It has a cross-sectional shape that is approximately a quarter-circle arc and engages with the other part.

[0018] Although not shown in the figure, the push button 11 is designed to move a piston located inside the pipette device body 1 forward and backward towards the tip of the nozzle cone. This movement allows liquid to be drawn in and out of the pipette tip 4, which will be described later, through the vent hole 24. The ejector 3 is cylindrical and is fitted onto the nozzle cone 2 so as to be slidable in the axial direction of the nozzle cone 2, and its lower end surface has an inner diameter smaller than the outer diameter of the pipette tip 4.

[0019] As shown in Figure 1, the ejector 3 has an engaging projection 31 at its upper end that engages with an engaging groove 12a at the lower end of the ejector operating section 12, and is designed to descend when the ejector operating section 12 is pushed downward. The pipette tip 4 is made of the same material as conventional products and has an undercut with an arc-shaped cross-section. This undercut is used as a tip-side engagement recess 41, and the rear end is provided with an ejector receiving surface 42.

[0020] The following describes how to use this pipette device A. [Attaching pipette tip 4] As shown in Figure 2(a), the lower end of the nozzle cone is positioned above the pipette tip 4, and then, as shown in Figure 2(b), the pipette device body 1 and the pipette tip 4 are moved relative to each other so that the fitting portion 23 of the nozzle cone fits into the pipette tip 4. Furthermore, as the nozzle cone fitting portion 23 is inserted into the pipette tip 4, the pipette tip 4 undergoes elastic deformation such that its wall surface bends outward due to the cone-side engaging projection 23a. As shown in Figure 2(c), the fitting portion 23 is further inserted into the pipette tip 4 until the stopper projection 22a contacts the ejector receiving surface 42. As the stopper projection 22a contacts the ejector receiving surface 42, the cone-side engaging projection 23a fits into the tip-side engaging recess 41, and the wall surface of the pipette tip 4 returns to its original state due to the elastic restoring force, so that the outer circumferential surface of the cone-side engaging projection 23a is in close contact with the inner wall surface of the tip-side engaging recess 41. Furthermore, when the cone-side engaging projection 23a fits into the tip-side engaging recess 41 due to the elastic restoration described above, a click sensation is transmitted to the user's hand, indicating that the device has been properly engaged. hoe Light.

[0021] [Removing pipette tip 4] The ejector operating unit 12 is operated to bring the lower end surface of the ejector 3 into contact with the ejector receiving surface 42 of the pipette tip 4, as shown in Figure 3. Then, the ejector 3 is further slid toward the tip of the nozzle cone to detach the pipette tip 4 from the nozzle cone.

[0022] As this pipette device A is configured as described above, it has the following effects and benefits. (1) Since a stop projection 22a is provided, the fitting portion 23 of the nozzle cone will not be inserted into the pipette tip 4 beyond the normal fitting position. (2) As the stopper projection 22a contacts the ejector receiving surface 42, the cone-side engaging projection 23a engages into the tip-side engaging recess 41, so that a click sensation is transmitted to the user's hand, making it easy to feel that the engagement has been completed correctly, and thus improving work efficiency. (3) Since conventional general-purpose products can be used as pipette tips 4, the pipette device body 1 can be manufactured without incurring additional costs by simply changing the nozzle cone portion of the pipette device body 1.

[0023] The present invention is not limited to the embodiments described above. For example, in the above embodiment, only one pipette tip could be attached to the pipette device body, but multiple nozzle cones can be arranged in parallel, and a pipette tip can be attached to the tip of each nozzle cone, allowing for simultaneous aspiration and discharge of liquid to each pipette tip with the operation of a single push button. In the above embodiment, the nozzle cone had a cone-side engaging projection and the pipette tip had an undercut recess which was a tip-side engaging recess. However, it is also acceptable to provide a cone-side engaging recess at the lower end of the fitting portion of the nozzle cone and a tip-side engaging projection on the inner surface of the pipette tip.

[0024] In the above embodiment, as shown in Figure 1, the ejector can be operated by the ejector operating section by engaging the engagement projection of the ejector with the engagement groove of the ejector operating section. However, it is also possible to connect them by other means, and the connecting section may be housed inside the casing of the pipette device body so that it is not visible from the outside. [Explanation of Symbols]

[0025] A Pipette device 1. Pipette device body 11 Push buttons 12 Ejector operating section 12a Engagement groove 2 Nozzle cones 21 Head 22 Ejector slide section 22a Stopper protrusion 23 Fitting part 23a Cone-side engaging projection 23b Fitting part body 24 ventilation holes 3 Ejectors 31 Engagement protrusion 4 pipette tips 40 Tip-side tapered cylinder section 41 Chip-side engagement recess 42 Ejector receiving surface

Claims

1. Pipette tips, and, A nozzle cone having a fitting portion at its tip that is inserted and fitted into the rear end of the pipette tip, and an ejector slide portion at the rear end of the fitting portion that expands in a stepped manner from the rear end of the fitting portion and has a stopper protrusion formed on the side end of the fitting portion, The pipette device body comprises an ejector fitted onto the nozzle cone so as to be slidable in the axial direction of the nozzle cone, A pipette device in which, with the fitting portion of the nozzle cone fitted to the rear end of the pipette tip, the ejector slides toward the tip of the nozzle cone and presses against the rear end of the pipette tip, thereby enabling the pipette tip to be detached, The pipette tip has a tip-side tapered cylindrical portion at its rear end, the inner wall of which gradually narrows in diameter towards the tip, and a ring-shaped tip-side engaging recess is provided in a part of this tip-side tapered cylindrical portion, recessed from the wall surface of the tip-side tapered cylindrical portion. The fitting portion of the nozzle cone has a fitting portion body that is approximately frustoconical in shape, with a tapered outer wall surface that gradually decreases in diameter towards its tip and fits into the tip-side tapered cylindrical portion, The tip of this fitting part body has a cone-side engaging projection that protrudes in a ring shape from the fitting part body outward, A pipette device characterized in that the cone-side engaging projection is formed such that, as the fitting portion is inserted into the pipette tip, it elastically deforms the inner wall surface of the rear end of the pipette tip so as to bend outward, and when it reaches a position where the stopper projection is in contact with the pipette tip, it fits into the tip-side engaging recess.

2. The tip-side engagement recess is formed in the shape of a groove with a substantially arc-shaped cross-section, The pipette device according to claim 1, wherein the cone-side engaging projection follows the cross-sectional shape of the tip-side engaging recess, gradually widening toward the tip of the fitting portion body, and is formed in a cross-sectional shape of approximately 1 / 4 arc that follows the cross-sectional shape of the tip-side engaging recess.

Images