JP2003098184A - Dispensing nozzle, nozzle chip, and dispensing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dispensing nozzle for mounting a nozzle chip with relatively small force and high positioning accuracy, a nozzle chip, and a dispensing apparatus. SOLUTION: The dispensing nozzle 12 comprises a nozzle base section 18, and a nozzle chip 20. A retaining surface 32 for retaining the nozzle chip 20 is provided on the side of a tip section 24 of the nozzle base section 18. Additionally, a taper surface 29 for positioning the nozzle chip 20 is provided at the base edge section 24 of the nozzle base section 18. A taper surface 26 is also provided at the peripheral end section of an opening at the base edge side of the nozzle chip 20. By bringing the taper surface 29 into contact with the taper surface 26, the nozzle chip 20 is positioned to the nozzle base section 18. Since the area of the retaining surface 32 is relatively small at the nozzle base section 18, press fit force can be reduced relatively when fitting the nozzle chip 20 to the nozzle base section 18.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dispensing nozzle to which a nozzle tip is attached and used, a dispensing device including the dispensing nozzle, and a nozzle tip attached to the dispensing nozzle.

[0002]

2. Description of the Related Art FIG. 5 is a view showing a dispensing nozzle 51 used in a conventional automatic dispensing apparatus.

The dispensing nozzle 51 comprises a hollow nozzle tip 52 made of, for example, resin, and a nozzle base portion 53 for mounting the nozzle tip 52. Dispensing is performed by sucking a required sample with the nozzle tip 52 and discharging the sucked sample into a plurality of test tubes (not shown) held upright in a rack (not shown).

The nozzle base 53 is substantially cylindrical and
An inclined surface 55 is provided laterally in a tapered shape whose diameter decreases toward the tip. The nozzle tip 52 has an elongated conical shape and has an inclined surface 56 on its inner wall. The base end side is provided with an opening 57 into which the nozzle base 53 is inserted,
An opening 58 for sucking and discharging the sample is provided on the tip side.

The operation of attaching the nozzle tip 52 to the nozzle base portion 53 is performed in the following procedure. Nozzle tip 52
Are loaded in advance in a rack (not shown) for nozzle tips. The nozzle base 53 is moved to a position above the nozzle tip 52 by a drive mechanism 54 such as an actuator.
Is transported. Next, after moving the nozzle base portion 53 vertically downward, the drive mechanism 54 presses the nozzle base portion 53 in the vertical direction until the nozzle base portion 53 fits with the nozzle tip 52 and can hold it sufficiently. .

When the nozzle base portion 53 is vertically pressed by the driving mechanism 54, the inclined surface 55 provided on the side of the nozzle base portion 53 and the inclined surface 5 of the nozzle tip 52.
6 and 6 contact. Furthermore, the inclined surface 55 of the nozzle base 53
Presses the inclined surface 56 of the nozzle tip 52 to maintain the airtightness inside the nozzle tip 52.
Is retained. Further, since the contact surfaces (inclined surfaces 55, 56) are inclined, the nozzle tip 52 is positioned in the horizontal and vertical directions with respect to the nozzle base portion 53. If the area of the contact surface is made relatively large, the positioning accuracy can be secured accordingly. Here, the insertion depth of the nozzle base portion 53 is
Depending on the type of nozzle tip 52, 2 mm ~
It is about 5 mm.

[0007]

However, if the area of the contact surface is increased, the frictional force associated with the mounting of the nozzle tip 52 also increases, and the required driving mechanism 54 also needs a large power. There is a problem that the dispensing device becomes large-scale. Therefore, if the area of the contact surface is reduced, the drive mechanism 54 can be downsized, but as described above, if the contact surface is small, it is difficult to secure the positioning accuracy.

Further, the shape of the inner wall of the nozzle tip 52 varies due to defective molding. In some cases,
Due to the variation, the fitting depth of the nozzle tip 52 is different, and it is necessary to adjust the position every time the nozzle tip 52 is attached. Then, there is a problem that the mounting work becomes complicated.

Further, when the nozzle tip 52 is attached to the nozzle base portion 53 as described above, the nozzle tip 5
The work of holding 2 upright in the rack is automated,
A plurality of nozzle chips 52 are housed in one container (not shown), and each nozzle chip 52 is taken out from the container and automatically loaded into the rack. However, when the nozzle tip 52 has a conical shape as shown in the drawing, the tip of the nozzle tip 52 enters the opening 57 on the base end side of another nozzle tip 52 in the container,
Before removing the nozzle tips 52, both nozzle tips 52
There is a problem that the automatic loading work cannot be performed efficiently because it is necessary to separate them.

The present invention has been made in view of the above problems, and a first object thereof is to be able to attach a nozzle tip with a relatively small force and to position the nozzle tip with high accuracy. An object of the present invention is to provide a dispensing nozzle, a nozzle tip attached to the dispensing nozzle, and a dispensing device including the dispensing nozzle.

A second object of the present invention is to provide a nozzle tip in which the tip of the nozzle tip does not enter the opening on the base end side of another nozzle tip.

[0012]

(1) In order to achieve the above first object, a dispensing nozzle according to the present invention has a hollow nozzle tip and a nozzle base to which the nozzle tip is attached. In a pouring nozzle, the nozzle base portion is provided at the tip of the nozzle base portion, a chip holding portion that presses the inner wall of the nozzle tip to hold the nozzle tip, and is provided above the tip holding portion, A tip positioning portion that engages with a peripheral edge portion of the opening on the base end side of the nozzle tip to position the nozzle tip.

As described above, since the portion for holding the nozzle tip and the portion for positioning the nozzle tip are provided independently of each other, the dispensing nozzle for accurately positioning the nozzle tip as in the prior art. The nozzle tip can be attached to the nozzle base with a relatively small force without the need to provide a wide contact surface on the side of the nozzle or on the inner wall of the nozzle.

Desirably, the nozzle tip has an engaging portion that engages with the tip positioning portion at a peripheral portion of the opening on the base end side. By providing the engaging portion that engages with the tip positioning portion on the nozzle tip side, the positioning accuracy of the nozzle tip can be improved.

The manner in which the nozzle tip positioning portion and the engaging portion are engaged can take various forms such as fitting and abutting. For example, one of the two may be provided with a convex member and the other may be provided with a concave member so that the nozzle tip can be positioned by fitting both members. Alternatively, both may be provided with horizontal planes and the positioning may be performed by contacting both horizontal planes.

Further, the tip positioning portion is provided with a tapered surface, and the engagement portion is provided with a tapered surface that abuts the tapered surface of the tip positioning portion at a peripheral edge portion of the base end side opening. . By doing this, with a simple configuration,
The nozzle tip can be positioned horizontally and vertically.

The nozzle base is characterized in that the portion between the tip holding portion and the tip positioning portion has a constricted shape. When attaching the nozzle tip to the nozzle base, the nozzle tip may be tilted with respect to the nozzle base from a normal mounting posture. In such a case, it is necessary to return the posture of the nozzle tip to the normal one when mounting. The nozzle base portion has a constricted portion between the tip holding portion and the tip positioning portion, and therefore, when mounting the nozzle tip, a large space can be secured in the gap portion between the nozzle base portion and the nozzle tip. Therefore, the posture of the nozzle tip can be smoothly corrected by utilizing this space.

(2) In order to achieve the second object,
The nozzle tip according to the present invention is characterized in that the tip has a stopper portion having an outer diameter larger than the inner diameter of the opening on the base end side. According to the above configuration, the stopper portion can prevent the tip of the nozzle tip from entering through the opening on the base end side of another nozzle tip.
For example, even when a plurality of nozzle chips are stored in the storage container, the tip of the nozzle chip can be prevented from entering through the opening on the base end side of another nozzle chip.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention (hereinafter referred to as embodiments) will be described below with reference to the drawings.

FIG. 1 is a diagram showing a main configuration of a dispensing device 10 according to an embodiment of the present invention.

The dispensing device 10 includes a dispensing nozzle 12, a dispensing pump 14, a driving mechanism 16 for the dispensing nozzle 12, and a controller 17.
It is configured to include.

The dispensing nozzle 12 comprises a nozzle base portion 18 and a nozzle tip 20. An air flow path 19 is formed in the nozzle base portion 18. In the dispensing nozzle 12,
The dispensing pump 14 is connected via the air tube 22. The dispensing pump 14 is composed of a cylinder and a piston, and the dispensing nozzle 12 performs a suction operation and a discharge operation of a sample, a reagent, etc. by a change in the air pressure caused by the forward / backward movement of the piston. The drive mechanism 16 can convey the dispensing nozzle 12 in a three-dimensional direction. Since the structure itself of the drive mechanism 16 is well known, detailed description thereof will be omitted. Control unit 1
7 is realized by a microcomputer or the like that controls the operations of the dispensing pump 14 and the drive mechanism 16 and controls the entire dispensing device 10.

The nozzle base 18 has a cylindrical shape and is made of metal such as stainless steel.

An annular tapered surface 26 for positioning the nozzle tip 20 in the vertical and horizontal directions is formed on the base end portion 24 of the nozzle base portion 18. The inclination angle of the tapered surface 26 is, for example, 45 degrees. An annular taper surface 29 having the same inclination angle as the taper surface 26 is also formed on the peripheral edge portion 28 of the opening 27 on the base end side of the nozzle tip 20. By contacting the taper surface 26 and the taper surface 29, the nozzle The nozzle tip 20 is positioned with respect to the base portion 18.
Here, the tilt angle is not limited to that of this embodiment, and a suitable tilt angle is appropriately adopted.

On the side surface of the tip portion 30 of the nozzle base portion 18,
A holding surface 32 for holding the nozzle tip 20 is provided. The holding surface 32 is the inner wall 33 of the nozzle tip 20.
By abutting against and pressing it, the nozzle tip 20 is held by the frictional force generated by the pressing. The inner surfaces of the holding surface 32 and the inner wall 33 may be inclined surfaces. A rounded guide surface 34 is formed at the tip of the tip portion 30, and when the nozzle base portion 18 is inserted into the nozzle tip 20, the guide surface 34 is guided by the tapered surface 29 of the nozzle tip 20.

In the nozzle base portion 18, the central body portion 35 sandwiched between the base end portion 24 and the tip end portion 30 has a constricted shape.

In the nozzle base 18, the holding surface 32 is
The tapered surface 26 has a function of holding the nozzle tip 20.
The nozzle chip 20 has a positioning function independently of each other. Conventionally, since the contact surface that contacts the inner wall of the nozzle tip has both functions, it is necessary to increase the area of the contact surface. In the present embodiment, the height of the holding surface 32 in the vertical direction is, for example, about 1 mm, and the area thereof is relatively small. Therefore, when the nozzle base 18 is inserted into the nozzle tip 20, the force required for the press-fitting is not required. Can be relatively small. Compared with the above-mentioned conventional example, the force required for the press-fitting is reduced to about 1/2 to 1/5 times.

The nozzle tip 20 has a hollow tube shape and is made of, for example, resin. Nozzle tip 20
An opening 36 for sucking and discharging a sample or the like is provided at the tip of the
Is provided, and an opening 27 into which the nozzle base 18 is inserted is provided on the base end side.

As described above, the peripheral edge portion 28 of the opening 27 on the base end side is provided with the tapered surface 29 that abuts the tapered surface 26 of the nozzle base portion 18 to position the nozzle tip 20. Further, the peripheral edge portion 28 is formed with a hook portion 38 that engages with the peripheral edge portion of the opening of the insertion groove provided in the rack when the nozzle tip 20 is loaded into the nozzle tip rack.

A thick stopper portion 39 is formed on the tip side of the nozzle tip 20. For example, at the position where the stopper portion 39 is provided, the total length of the nozzle tip 20 is about 100 mm.
In the case of, the position is 18 mm from the tip. The outer diameter of the stopper portion 39 is 8 mm, for example, and is formed larger than the inner diameter 6 mm of the opening 27. This way, the nozzle tip 20
It is possible to prevent the tip of the nozzle from entering the base end side opening of another nozzle tip 20 having the same shape (see FIG. 4).

FIG. 2 shows the nozzle tip 20 with the nozzle base 1
It is a figure showing the process attached to FIG.

The nozzle tip 20 is loaded in the rack 40 in advance with the hook portion 38 and the peripheral edge portion 42 of the insertion groove 41 engaged with each other. The nozzle base 18 is conveyed to a position above the nozzle tip 20 by the drive mechanism 16. After that, the drive mechanism 16 moves the nozzle base 18 vertically downward (see (A) in the figure). Nozzle base 1
The nozzle base 18 is inserted into the nozzle tip 20 while the guide surface 34 at the tip of 8 is guided by the tapered surface 29 (see (B) in the figure). Next, the nozzle base 18 is pressed into the nozzle tip 20 by the drive mechanism 16 while the holding surface 32 slides on the inner wall 33 (see (C) in the figure). The nozzle base 18 is press-fitted until the tapered surface 26 contacts the tapered surface 29 on the nozzle tip 20 side. Drive mechanism 16
Is the nozzle base 1 with the tapered surfaces 26 and 29 in contact with each other.
The press-fitting of No. 8 is released (see (D) in the figure).

FIG. 3 is a diagram showing a mounting process when the axial center of the nozzle tip 20 is inclined with respect to the axial center of the nozzle base portion 18 at the time of mounting.

First, the nozzle base portion 18 is conveyed to a position above the nozzle tip 20 by the drive mechanism 16. The nozzle tip 20 is loaded in the insertion groove 41 of the rack 40 in a state in which the nozzle tip 20 is slightly tilted from the normal standing posture. In this state, when the nozzle base 18 is moved vertically downward,
At the beginning, the nozzle base 18 is inserted with the axial center of the nozzle tip 20 tilted with respect to the axial center of the nozzle base 18 (see (A) in the figure). Furthermore, the nozzle base 1
When 8 is press-fitted, the nozzle base portion 18 and the nozzle tip 20 are engaged with each other in a state where the tapered surface 26 and the tapered surface 29 are not in contact with each other (see (B) in the figure). When the nozzle base portion 18 is further press-fitted from this state, the nozzle tip 20 changes the position in contact with the nozzle base portion 18 and the insertion groove 41, and the posture thereof while being inserted into the insertion groove 41 changes. It is corrected to a normal standing posture. Here, since the body portion 35 of the nozzle base portion 18 is constricted, it is possible to secure a large space in the gap portion between the nozzle base portion 18 and the nozzle tip 20. Therefore, the posture of the nozzle tip 20 can be smoothly corrected. Can be done. Further, when the nozzle base 18 is press-fitted, the tapered surface 26 and the tapered surface 29
And abut each other, and the nozzle tip 20 returns to the upright posture. In the drive mechanism 16, the hook base 38 and the peripheral edge portion 42 of the insertion groove 41 are engaged with each other, and the axial center of the nozzle tip 20 is aligned with the axial center of the nozzle base portion 18.
Release the press-fitting (see (C) in the figure).

FIG. 4 is a diagram showing the relationship between the stopper portion 39 provided at the tip of the nozzle tip 20 and the opening 27 on the base end side. As described above, the outer diameter 44 of the stopper portion 39 is formed larger than the inner diameter 46 of the opening 27.
By doing so, it is possible to prevent the tip of the nozzle tip 20 from entering the opening 27 of another nozzle tip 20.

[0036]

Since the dispensing nozzle according to the present invention is provided with the portion for holding the nozzle tip and the portion for positioning the nozzle tip independently, the nozzle tip can be attached with a relatively small force. Further, it is possible to provide a dispensing nozzle with high positioning accuracy of the nozzle tip, a nozzle tip attached to the dispensing nozzle, and a dispensing device including the dispensing nozzle.

Further, since the nozzle tip according to the present invention is provided with the stopper portion having the outer diameter larger than the inner diameter of the opening on the base end side on the tip end, the tip of the nozzle tip is on the base end side of the other nozzle tip. It can be prevented from entering through the opening.

[Brief description of drawings]

FIG. 1 is a diagram of a dispensing device according to an embodiment of the present invention.

FIG. 2 is a view in which a nozzle tip is attached to a nozzle base.

FIG. 3 is a view showing how a nozzle tip is attached to a nozzle base.

FIG. 4 is a diagram showing a relationship between a stopper portion of a nozzle tip and an opening of a base end portion.

FIG. 5 is a view showing a conventional dispensing nozzle and nozzle tip.

[Explanation of symbols]

12 dispensing nozzle, 14 dispensing pump, 16 drive mechanism, 17 control unit, 18 nozzle base, 20 nozzle tip, 24 base end, 26, 29 taper surface, 27, 36
Opening, 28 peripheral portion, 30 tip portion, 32 holding surface,
33 inner wall, 34 guide surface, 35 body part, 38 hook part, 39 stopper part, 40 rack, 41 insertion groove, 42 peripheral part.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G01N 35/06 A F term (reference) 2G052 AD26 BA14 CA03 CA04 CA18 CA22 CA23 CA28 CA33 JA05 JA08 2G058 EA02 EA04 EB01 ED12 ED35 ED36 4G057 AB18 AB38 4G068 AA04 AB15 AC17 AD16 AD24 AD47 AE04 AF31 AF40

Claims (7)

[Claims] 1. A dispensing nozzle having a hollow nozzle tip and a nozzle base to which the nozzle tip is attached, wherein the nozzle base is provided at a tip of the nozzle base and presses an inner wall of the nozzle tip. And a chip holding part that holds the nozzle chip, and a chip positioning part that is provided above the chip holding part and that engages with the peripheral edge of the base end side opening of the nozzle chip to position the nozzle chip. A dispensing nozzle, comprising: 2. The dispensing nozzle according to claim 1, wherein the tip positioning portion has a tapered surface. 3. The dispensing nozzle according to claim 1, wherein the nozzle base portion has a constricted shape between a portion between the tip holding portion and the tip positioning portion. nozzle. 4. The nozzle tip attached to the nozzle base according to claim 1, wherein the nozzle tip has an engaging portion that engages with the tip positioning portion at a peripheral edge portion of the opening on the base end side. Nozzle tip. 5. The nozzle tip according to claim 4, wherein the engagement portion has a tapered surface at a peripheral edge portion of the opening on the base end side. 6. The nozzle tip according to claim 4 or 5, wherein the tip has a stopper portion having an outer diameter larger than the inner diameter of the opening on the base end side. . 7. A dispensing device comprising the dispensing nozzle according to claim 1.