JPS5893Y2 - Pipette control device - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a pipette control device.

When using a pipette to transfer small amounts of liquid, the traditional method is for the handler to draw the liquid into the pipette with their mouth, hold one end of the pipette with their fingertips to keep the drawn liquid in the pipette, and then Liquid is released by loosening or releasing the fingertips.

However, it is difficult to accurately control the amount of liquid inhaled or expelled using the above method, and there are hygienic problems, especially when the liquid is not good for health or has a bad odor.
Traditional oral inhalation methods are neither convenient nor suitable.

In order to avoid having to operate the pipette using the operator's mouth or fingers, it has been proposed to attach a liquid suction and ejection control device to one end of the pipette.

A cylinder/piston assembly is used as the control device, and the piston is made to be able to reciprocate inside the cylinder by a piston rod coupled thereto, and at the same time is elastically supported by a coil spring so that it can be pressed, and is attached to the bottom of the cylinder. is the port that connects the pipette mouthpiece) (
port) has been formed.

As a result, when the pipette mouth connected to the boat of the cylinder is inserted into the liquid to be aspirated, the suction and discharge operations by the pipette are controlled by the reciprocating movement of the piston within the cylinder.

However, although the use of the above-mentioned control device avoids the intervention of the operator's mouth and fingertips, the amount of fluid being drawn in or discharged remains uncontrollable.

Therefore, an object of the present invention is to provide a pipette control device that solves the above-mentioned problem of sucking in liquid with the mouth and controlling the discharge of liquid with the fingertips.

Another purpose of the present invention is that the pipetting device is easy to operate and achieves excellent control effect through a graduated device that can preset the volume of liquid to be aspirated, as well as a hand-operated controller for natural discharge of liquid and a manual control device that allows the user's body temperature to be adjusted by hand. To provide a pipette control device equipped with a heat shielding means that can more quickly enter the pipette control device and prevent the level of suction liquid from changing due to the body temperature of the pipette control device and making the level of the suction liquid unstable. be.

According to the present invention, there is provided a cylinder having a boat at the bottom that is equipped with a rubber sheet and a collet that tightly connects the mouthpiece of the inserted pipette; a piston that is capable of reciprocally sliding within the cylinder; and a screw screw whose one end is connected to the piston and whose other end movably protrudes from the upper end opening of the cap member and is coupled to the plunger. (threaded rod), in which a shaft-sealing flange is formed at the lower end of the plunger, the flange is urged against the inner upper surface of the cap member by a coil spring, and the coil spring connects the flange and the It is wound around the screw punch between the cylinders, and holds the plunger so that the upper end always protrudes outside the cap member, and also gives the plunger a restoring force; the plunger is made of a transparent material. a hollow tubular member consisting of; a lid that closes the upper end of the tubular member; a lid fixed to the lower end of the tubular member and threadedly engaged with and guided by the upper end of the screw thread by a threaded through hole; A nut member configured to raise or lower the screw screw relative to the side wall of the tubular member when the plunger is rotated; and a set of scales for indicating the volume of liquid drawn in by movement of the piston.

In a preferred embodiment of the invention, there is a second boat at the bottom of the cylinder of the pipette control device, again in communication with the outside atmosphere via a vent passage, which is normally attached to the cylinder and controls the natural evacuation of the liquid. It is closed by an operating lever system.

By actuating the lever system, a vent passage is opened, from which atmospheric pressure is introduced into the gap between the piston and the pipette connected to the first boat, causing liquid to naturally drain from the pipette mouth.

The cylinder is constructed with double walls, and the annular space between the outer wall and the inner wall acts as a heat shield.

Further, a heat shielding layer made of a heat insulating material is formed on the outer peripheral surface of the cylinder to prevent changes in ambient temperature or the body temperature of the operator from affecting the air pressure inside the cylinder.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 and 2 show an embodiment of the present invention.

Reference numeral 13 denotes a cylinder of the pipette control device, which has a cylindrical inner wall, a circular outer wall, and a bottom.

A piston 10 is located inside the cylinder 13 surrounded by the inner wall and the bottom, and is connected to the screw punch 5 via an adapter 101.

At the bottom of the cylinder 13 is a port 14 having a sealing member 15 and a stem 16, which can be tightly coupled to the port 14 by tightening the stem 16 when the pipette tip is inserted.

The upper end of the cylinder 13 is closed by a fixing panel 9 having a hole in the center through which an adapter 101 extends to the outside, and at the same time is connected by a connecting ring 11 to a cap member 12 which is generally U-shaped in cross section.

The upper end of the screw punch is connected to a plunger 1, which will be described later.

The plunger 1 protrudes movably from the inside of the cap member 12 to the outside through a center hole provided at the upper end of the cap member, and has a flange 41 having a width and shape that coincides with the periphery of the center hole.
has.

A coil spring 8 wound around the screw punch 5 elastically urges the plunger 1 toward the top dead center between the plunger 1 and the fixed panel 9, and the flange 41 is brought into contact with the inner upper end surface of the cap member 12. It is made to be in contact with each other.

Therefore, by pressing and releasing the plunger 1, the piston 10 moves within the cylinder 13.

That is, the port 14 is opened by pressing and releasing the plunger.
A pipette connected to aspirates the liquid.

It should be noted that the end of the coil spring 8 is attached to a washer 7, which is located on the same line as the plunger 1, and has a large number of papillary protrusions formed on the surface that contacts the lower end surface of the plunger 1. The plunger 1 is designed to reduce frictional resistance when it rotates.In addition, in order to provide ease of pipetting operation and excellent controllability, the plunger 1 and the screw are designed to reduce the frictional resistance when the plunger 1 rotates. A scale reading device is provided on the punch 5, and a manually operated natural discharge control device is provided inside the cylinder.

As shown in FIGS. 1, 2, and 3, the plunger 1 is a tubular member made of a transparent material, the upper end of which is closed by a lid 3, and the lower end connected to a nut member 4.

The nut member 4 has a through hole carved with a thread,
The upper end of the screw punch 5 is screwed together and guided by the through hole, so that when the plunger 1 is rotated clockwise or counterclockwise, the upper end of the screw punch 5 does not touch the plunger wall. make an upward or downward movement.

That is, the position of the piston within the cylinder is precisely adjusted by rotating the plunger 1.

Furthermore, scales 2 are coated with iron film at intervals on the wall surface of the plunger 1, and are graduated in accordance with the amount of liquid sucked in by the movement of the screw. is fixed, and the scale is read according to the position of the piston.

As shown in FIG. 2, a second relatively small diameter port 21 is provided at the bottom of the cylinder and communicates with the outside atmosphere via a laterally extending air passage 20.

Also, a manual control device 17 including an operating lever system is attached to the bottom of the cylinder 13 and is normally connected to the air passage 20.
The opening is closed and the opening is opened by manual operation of a lever.

As shown in detail in FIG. 4, the operating lever system comprises a lever arm 171.on which a seal holder 18 is formed at one end. Consisting of a pair of claws 173, 174 and a protrusion 172, the claws 173, 174 clamp the outer wall of the port 14 at the bottom of the cylinder 13, and the seal pad 19 held by the seal holder 18 closes the opening of the air passage 20. The cylinder 13 is airtightly sealed, and the protrusion 172 is in contact with the surface of the cylinder 13 as shown in FIG.

When using the pipette control device shown in FIG. 1 or FIG.
5, tighten the shaft assembly 16 to make a complete seal, and then turn the plunger 1 so that the indicator disk 6 matches the desired scale to preset the volume of liquid to be aspirated by the pipette. .

Simply push down the plunger 1 until it reaches the bottom dead center, insert the pipette mouth into the liquid to be aspirated, release the pressure on the plunger 1, and return it to its original position. A preset volume of liquid can be inhaled by simply adjusting the scale.

Thereafter, the liquid in the pipette is discharged by gradually pushing down the plunger 1 to force out the liquid, or by turning the plunger 1 in the EX direction (see FIG. 1) to precisely control the discharge of a small amount of liquid.

If the accuracy of the pipetting operation used depends on natural ejection, a manual control 17 is required, i.e. by pressing the lever arm 171 against the cylinder side as a fulcrum of the projection 172'l, the sealing The pad 19 is pushed up slightly over the opening of the vent 20 and atmospheric pressure is introduced through the vent 20 into the space between the piston and the pipette mouthpiece, thereby causing the liquid to drain under its own weight.

This manual control is also used to dispense a volume of liquid corresponding to the distance between the scale markings on the surface of the pipette.

The level stability of the aspirated liquid is easily influenced by the air pressure present in the space between the piston and the pipette nozzle, and the air pressure present in the space between the piston and the pipette nozzle is transmitted to said space via the cylinder wall. It is affected by the body heat emitted from the hands.

Therefore, as shown in FIG. 2, the cylinder 13 is constructed with a double wall, and the annular space surrounded by the inner and outer walls acts as a heat insulating wall, and the body temperature of the operator who is holding the cylinder with his hand is transferred to the cylinder. to prevent transmission to the central space of the body.

FIG. 5 shows another embodiment of the present invention, in which a plurality of parallel slots 22 are formed in the outer wall of the double-walled cylinder 13 and spaced apart from each other along the circumferential direction. is the same as in the previous embodiment.

The space formed by the slot formed on the circumference of this outer wall is created by the temperature of the operator at the center of the cylinder.
The effect on the space is reduced by reducing the contact area with the hand and dissipating heat outward, thereby achieving a more effective heat insulation effect.

On the other hand, if the cylinder of the pipette control device is not of double wall construction and therefore does not have the outer wall shown in FIG.
A heat shield is used as shown in the figure.

The heat shield shown in FIG. 6 is made of a heat insulating material and is generally tubular in shape, the inner diameter of which is substantially the same as the outer diameter of the cylinder.

Furthermore, an annular projection 232 and an annular groove 233 are formed on the surface, and each annular groove is sandwiched between two annular projections.

A notch 231 is formed in the lower part of the heat shield, and when the manual control part 17 is attached, the protrusion 172 comes into contact with the cylinder wall from there.

The pipette control device according to the present invention is operated with the thumb and forefinger and can perform all the functions that a pipette should have, such as aspirating liquid, repeatedly aspirating a preset volume, ejecting liquid including spontaneous ejection of a spherical pipette, and discharging a small amount. - Equipped with functions such as titration function, liquid ejection in the volume between the scales engraved on the pipette, and liquid ejection in conditions such as safe, quick, convenient and reliable.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an embodiment of the pipette control device according to the present invention, FIG. 2 is a longitudinal cross-sectional view of the pipette control device shown in FIG. 1, and FIG. 3 is a cross-sectional view of the pipette control device shown in FIG. 4 is a perspective view of the operating lever system removed from the pipette control device shown in FIG. 1; FIG. 5 is a front view showing another embodiment of the pipette control device according to the present invention; FIG. This embodiment is the same as the embodiment shown in FIG. 1 except that a heat shield is formed on the outer peripheral surface. FIG. 6 is a perspective view of the heat shield fitted into the outer circumference of the cylinder of the pipette control device. 1... Plunger, 3... Lid, 4...
... Nut member, 5 ... Screwdriver, 6 ...
...Indication disk, 8...Coil spring, 10...
... Piston, 12 ... Cap member, 13
...Cylinder, 41...Flange.

Claims (4)

[Scope of utility model registration request] (1) The mouthpiece of the inserted pipette
e) Rubber sheet and collet to tightly connect the
); a cylinder having a second port at the bottom that communicates with the outside air through a ventilation passage; a cap having a substantially U-shaped vertical section installed coaxially at the upper end of the cylinder; a member; a piston capable of reciprocally sliding within the cylinder; a thread having one end connected to the piston and the other end protruding outward from the upper end opening of the cap member and screwed into the plunger assembly;
ed rod); a pipette control device comprising an operating lever assembly for closing the vent passage and controlling the natural evacuation of liquid from an inserted pipette; The flange is biased against the inner upper surface of the cap member by a coil spring, and the coil panel is wound around the screw punch and positioned between the flange and the cylinder, so that the upper end of the plunger assembly is always attached to the cap member. The plunger assembly includes a hollow tubular member made of a transparent material; and a lid that closes the upper end of the tubular member. and; fixed to the lower end of the tubular member and threadedly engaged with and guided by the upper end of the screw screw by a through hole having a thread, so that when the plunger is rotated clockwise or counterclockwise, the screw screw is inserted into the tubular member. A nut member configured to be raised or lowered relative to the side wall of the member; and display means carved at predetermined intervals on the side wall of the tubular member and provided at the upper end of the screw inside the tubular member to indicate suction by movement of the piston. a set of scales indicating the volume of liquid drawn, the volume of liquid drawn by the pipette being preset by rotating the plunger and aligning the indicating means with the selected scale; A pipette control device featuring: (2) the operating lever assembly includes a lever arm; a seal pad fixed to one end of the lever arm and selectively sealing the air passageway; a pair of claws that are separably held at the bottom of the cylinder and airtightly seal the air passage with the seal pad; Utility model registration claim 1, characterized in that it includes a protrusion that comes into contact with the cylinder wall and acts as a fulcrum when the other end is pushed toward the cylinder side and shifts, thereby causing the natural discharge of the liquid. Pipette control device as described. (3) The cylinder is characterized by comprising an inner wall forming a cylindrical space in which the piston reciprocates, and an outer wall defining an annular space between the inner wall and the annular space functioning as a heat insulating wall. A pipette control device according to claim 1 or 2 of the utility model registration claim. (4) A plurality of annular protrusions and annular grooves are formed on the outer peripheral surface of the outer wall of the cylinder in parallel with each other at intervals along the circumference, and each annular groove is formed into two annular protrusions. The pipette control device according to claim 3, characterized in that the pipette control device is sandwiched between the pipettes.