JP2007139469A - Nozzle device and its controller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To appropriately control a mounting force in mounting a nozzle tip, and to avoid complication of the structure of a nozzle base. <P>SOLUTION: When a disposable tip 102 is mounted to the nozzle base 101, the nozzle base 101 is positioned above the nozzle tip to be mounted. When a nozzle device 100 is dropped in this state, and the front end of the nozzle base 101 is butted on and engaged with the upper end opening of the disposable tip 102, a movable body 104 moves upward against the elastic force of a coil spring 602 so as to be pressed up to a flange section 106a of a rod 106. At this time, a fitting detecting section 600 detects a displacement amount of upward movement of a detected section 603, namely a displacement amount of upward movement of the movable body 104, in other words, the contraction amount of the coil spring 602, is detected by a noncontact system. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a nozzle device configured to mount a nozzle tip on a nozzle base, and a control device for controlling the nozzle device.

  For example, in the field of examining blood collected from a human body, serum obtained by centrifuging blood is dispensed by an automatic dispensing device. This type of automatic dispensing device is equipped with a nozzle device configured to mount a nozzle tip on a pipe-like nozzle base.

  In the automatic dispensing device, the nozzle device including the nozzle base is supported by a transport mechanism that transports in the XYZ triaxial directions. When mounting the nozzle tip, first, the nozzle base is positioned above the nozzle tip held in the tip rack. Thereafter, by lowering the nozzle device, the tip of the nozzle base is inserted into the upper end opening of the nozzle tip, and the two are fitted together.

  At the time of mounting such a nozzle tip, the mounting force (fitting pressure) is adjusted by controlling the amount of lowering of the nozzle device (nozzle base).

JP-A-11-281654

  However, when adjusting the mounting force only by the lowering amount of the nozzle base, for example, when there is an individual difference in the taper angle inside the upper end opening of the nozzle tip or when the tip of the nozzle base is worn, Variation will occur. If the mounting force varies in this manner, a problem such as air leaking from the fitting portion between the nozzle base and the nozzle tip may occur, and the dispensing accuracy may be adversely affected.

  In order to avoid problems such as air leakage due to variation in mounting force, the lowering amount of the nozzle base may be slightly larger than the appropriate lowering amount in order to make the fitting pressure slightly larger than the appropriate value, There is a problem in terms of durability of the nozzle base and nozzle tip.

  On the other hand, for example, Patent Document 1 discloses a nozzle device in which a sensor for detecting the mounting force is provided on the outer peripheral surface (mounting surface) of the nozzle base for the purpose of appropriately controlling the mounting force of the nozzle tip. Yes.

  However, in the nozzle device disclosed in Patent Document 1, since the sensor is provided on the mounting surface of the nozzle base that comes into contact with the nozzle tip, the structure of the nozzle base becomes complicated, which increases the cost.

  In addition, since the sensor is provided on the mounting surface of the nozzle base that is in contact with the nozzle tip, there is a possibility that the sensor may be worn or the detection accuracy may be deteriorated while the nozzle tip is attached and detached many times. In particular, when a disposable chip is used as the nozzle chip, since it is repeatedly attached and detached, some measures are required for sensor wear and detection accuracy degradation.

  The present invention has been made in view of the above points, and it is possible to appropriately control the mounting force when mounting the nozzle tip, and to avoid the complicated structure of the nozzle base. To do. Another object is to reduce sensor wear and deterioration of detection accuracy.

The nozzle device according to the present invention is a nozzle device configured to mount the nozzle tip on the nozzle base by lowering the nozzle base toward a nozzle tip for sucking and discharging liquid. When a chip is mounted, a movable body that is displaced according to the mounting force, an elastic member that biases an elastic force that resists the displacement of the movable body, and a detection unit that detects a displacement amount of the movable body It is characterized by the points provided.
Another feature of the nozzle device according to the present invention is that the detecting means detects a displacement amount of the movable body in a non-contact manner.
A control device for a nozzle device according to the present invention is a control device for controlling the nozzle device according to the present invention, wherein when the displacement detected by the detection means reaches a set value, the nozzle device is lowered. It is characterized in that it is provided with a control means for stopping the operation.

  According to the present invention, when the nozzle chip is mounted, the movable body includes a movable body that is displaced according to the mounting force, and an elastic member that biases an elastic force that resists the displacement of the movable body. Therefore, it is possible to appropriately control the mounting force when mounting the nozzle tip, and to avoid the complicated structure of the nozzle base. Moreover, when detecting the displacement amount of a movable body by a non-contact system, wear of a sensor and deterioration of detection accuracy can be reduced and it can endure long-term use.

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.
FIG. 1 is a diagram showing a schematic configuration of an automatic dispensing device equipped with the nozzle device of the present embodiment. In the figure, reference numeral 100 denotes a nozzle device, which will be described in detail later. The disposable tip 102 is detachably attached as a nozzle tip to a metal pipe-like nozzle base (tip fitting) 101.

  Reference numeral 200 denotes a control unit that controls each unit of the automatic dispensing apparatus, and is configured by, for example, a CPU of a computer.

  Reference numeral 300 denotes an XYZ driving unit realized by a stepping motor, X-axis, Y-axis, and Z-axis arms, and the nozzle device 100 is moved in the X-axis, Y-axis, and Z-axis directions in accordance with signals from the control unit 200. .

  A syringe pump 400 is connected to the nozzle base 101 via a pipe 401 such as a flexible tube. By moving the piston 400b in the cylinder 400a, the air pressure in the nozzle base 101 and the disposable chip 102 is changed via the pipe 401, and the liquid is sucked and discharged by the disposable chip 102.

  Reference numeral 500 denotes a pump drive unit, which drives and controls the piston 400b of the syringe pump 400 in accordance with a signal from the control unit 200.

  Reference numeral 600 denotes a fitting detection unit mounted on the nozzle device 100. As will be described in detail later, when the disposable chip 102 is mounted, a movable body that is displaced according to the mounting force (fitting pressure), and the displacement of the movable body A coil spring that urges an elastic force against the above and a sensor that detects a displacement amount of the movable body in a non-contact manner, and outputs a detection signal to the determination unit 700.

  Reference numeral 700 denotes a determination unit that determines whether or not the mounting force of the disposable chip 102 is appropriate based on a signal detected by the fitting detection unit 600.

  Reference numeral 800 denotes a memory that stores setting values used for determination by the determination unit 700. An input unit 900 is used for an operator to perform various settings and the like, and is configured by, for example, a keyboard and a mouse. Reference numeral 1000 denotes a display unit for displaying various types of information, and is configured by a liquid crystal display, for example.

  In FIG. 2, the structure of the nozzle apparatus 100 of this embodiment is shown. The nozzle device 100 includes a support frame 103 supported by a Z-axis arm (not shown) so as to be movable up and down.

  A movable body 104 is assembled to the support frame 103 through a slider 105 so as to be movable up and down. The movable body 104 has a pair of upper and lower plate portions 104a and 104b, and a rod 106 is provided so as to penetrate the plate portions 104a and 104b.

  A coil spring 107 for detecting jamming is disposed around the rod 106, and this coil spring 107 is supported by a spring receiving plate 108 on the upper plate portion 104a and the lower plate portion 104b. The spring receiving plate 108 is fixed to the rod 106.

  A flange portion 106 a is formed at the lower end of the rod 106, and the flange portion 101 a at the upper end of the nozzle base 101 is fixed to the flange portion 106 a. The nozzle base 101 is in the form of a metal pipe having a flange portion 101a formed at the upper end, and the connection port 101b of the pipe 401 is provided in the flange portion 101a. Further, the outer peripheral surface of the tip of the nozzle base 101 is processed into a taper shape, and the taper surface is a mounting surface of the disposable chip 102.

  Here, a jamming detection unit 109 is configured above the rod 106. The jamming detection unit 109 is for detecting a state in which, for example, the tip of the disposable chip 102 has accidentally collided with the edge of the container as a discharge destination in a state where the disposable chip 102 is mounted on the nozzle base 101.

  The jamming detection unit 109 will be further described. In a normal state, a slight gap 110 is formed between the lower surface of the lower plate portion 104b of the movable body 104 and the upper surface of the flange portion 106a of the rod 106. In this state, when the disposable tip 102 mounted on the nozzle base 101 collides with some object, the rod 106 moves upward against the elastic force of the coil spring 107 by the gap 110. The upward movement of the rod 106 is detected by the detected portion 111 standing on the rod 106 and the sensor 112 including, for example, a light projecting portion and a light receiving portion, and the tip of the disposable tip 102 is the edge of the container to which the discharge is made. It detects the state of accidental collision. In the case of jamming detection, the displacement amount of the rod 106 is about 0.1 to 0.2 mm.

  Further, the fitting detection unit 600 shown in FIG. 1 is configured above the movable body 104. The fitting detection unit 600 will be further described. A rod member 601 is erected on the upper surface of the movable body 104, and the rod member 601 passes through the upper wall portion 103 a of the support frame 103. A coil spring 602 for detecting a fitting is disposed around the rod member 601, and the coil spring 602 is supported by the upper wall portion 103 a of the support frame 103 and the upper surface of the movable body 104. A thin plate-like detected portion 603 is erected on the upper end of the rod member 601 and detects the amount of displacement of the detected portion 603.

  A configuration example of the fitting detection unit 600 will be described with reference to FIG. As a sensor of the fitting detection unit 600, for example, an optical linear encoder may be used as shown in FIG. That is, the diffraction grating 604 is provided in the detected part 603, and the light projecting part 605 that irradiates light to the detected part 603 and the light receiving part 606 that receives the diffracted light reflected by the diffraction grating 604 are disposed. . In the fitting detection unit 600 thus configured, the detected unit 603 moves up and down as the movable body 104 moves up and down (see arrow Z in the figure). Then, by detecting the change in the diffracted light reflected by the diffraction grating 604, the displacement amount of the upward movement of the detected portion 603, that is, the displacement amount of the upward movement of the movable body 104, in other words, the contraction amount of the coil spring 602 is detected. can do.

  Further, as shown in FIG. 3B, a one-dimensional PSD (position detecting element) 607 having a band-shaped light receiving surface and detecting the position in the longitudinal direction may be used. That is, a slit 609 is formed in the detected portion 603, and a light projecting portion 608 that irradiates light to the detected portion 603 and a PSD 607 that receives light passing through the slit 609 are disposed. In the fitting detection unit 600 thus configured, the detected unit 603 moves up and down as the movable body 104 moves up and down (see arrow Z in the figure). Then, by detecting the position of the light passing through the slit 609, the displacement amount of the upward movement of the detected portion 603, that is, the displacement amount of the upward movement of the movable body 104, in other words, the amount of contraction of the coil spring 602 is detected. Can do.

  In the nozzle device 100 shown in FIG. 2, when the disposable chip 102 is mounted on the nozzle base 101, the nozzle base 101 is placed above the nozzle chip to be mounted among a large number of nozzle chips held by a chip rack (not shown). Position. In this state, the nozzle device 100 is lowered, and the tip of the nozzle base 101 is brought into contact with the upper end opening of the disposable chip 102 and fitted.

  When the nozzle device 100 is further lowered, the tip of the nozzle base 101 is strongly fitted into the upper end opening of the disposable chip 102. Then, after the rod 106 moves upward by the gap 110, the movable body 104 moves upward against the elastic force of the coil spring 602 so as to be pushed up by the flange portion 106a. At this time, as described above, the fitting detection unit 600 detects the displacement amount of the upward movement of the detected portion 603, that is, the displacement amount of the upward movement of the movable body 104, in other words, the contraction amount of the coil spring 602. In the case of fitting detection, the displacement amount of the movable body 104 is about 2 to 3 mm.

  Here, FIG. 4 shows the relationship between the amount of contraction of the coil spring 602 and the fitting pressure. As shown in the figure, the amount of contraction of the coil spring 602 and the fitting pressure are in a substantially proportional relationship. That is, when the disposable chip 102 is mounted on the nozzle base 101, the fitting detection unit 600 outputs a signal substantially proportional to the mounting force (fitting pressure) to the determination unit 700.

  Hereinafter, with reference to the flowchart of FIG. 5, a processing operation at the time of mounting the disposable chip 102 in the nozzle device 100 of the present embodiment will be described. A spring constant is registered in advance for the coil spring 602 for fitting detection.

  Further, before starting the automatic dispensing operation, for example, a desired fitting pressure is input according to the type of disposable tip to be mounted. When the fitting pressure is input, a contraction amount Ls of the coil spring 602 corresponding to the fitting pressure is calculated and set in the determination unit 700.

  When there is an instruction to start automatic dispensing operation and the disposable chip 102 is mounted, the control unit 200 attempts to mount the nozzle chip among a number of nozzle chips held in a chip rack (not shown) via the XYZ driving unit 300. The nozzle base 101 is positioned above the nozzle tip to be performed (step S101).

  Next, the control unit 200 lowers the nozzle device 100 via the XYZ driving unit 300 (step S102), and the tip of the nozzle base 101 is brought into contact with the upper end opening of the disposable chip 102 to be fitted.

  At this time, the determination unit 700 compares the contraction amount Lx of the coil spring 602 sent from the fitting detection unit 600 with the contraction amount Ls set in advance as described above (step S103).

  When the contraction amount Lx of the coil spring 602 matches the contraction amount Ls, the determination unit 700 outputs a stop signal to the control unit 200 assuming that the fitting pressure has reached an appropriate fitting pressure. In response to this, the control unit 200 stops the lowering of the nozzle device 100 (step S104).

  After the mounting process of the disposable chip 102 is completed in this way, the control unit 200 moves up to an automatic dispensing process in which the nozzle device 100 is lifted via the XYZ driving unit 300 to suck and discharge the liquid sample. To do. Since this automatic dispensing process is known, its description is omitted here.

  As described above, when the disposable chip 102 is mounted, the movable chip 104 includes the movable body 104 that is displaced according to the mounting force and the coil spring 602 that biases the elastic force against the displacement of the movable body 104. Since the displacement amount of the body 104 (that is, the amount of contraction of the coil spring 602) is detected, the mounting force can be appropriately controlled when the disposable chip 102 is mounted, and the structure of the nozzle base 101 is complicated. Can be avoided.

  Further, since the displacement amount of the movable body 104 is detected by a non-contact method, the wear of the sensor and the deterioration of detection accuracy can be reduced, and it can withstand long-term use.

  As mentioned above, although this invention was demonstrated with embodiment, this invention is not limited only to embodiment, A change etc. are possible within the scope of the present invention. For example, in the above-described embodiment, the optical type is described as the non-contact type fitting detection unit. However, a magnetic field or the like may be used.

  Further, in the above-described embodiment, the configuration in which the movable body 104 indirectly holds the nozzle base 101 via the rod 106 has been described. However, if the configuration for detecting jamming is not necessary, the movable body 104 is moved to the nozzle base 101. May be held directly (that is, the movable body 104 and the nozzle base 101 do not move relative to each other).

  The control unit 200 and the determination unit 700 according to the above-described embodiment are configured by a CPU or MPU of a computer, a RAM, a ROM, and the like, and are realized by operating a program stored in the RAM or the ROM. Therefore, the program itself for realizing the functions of the above-described embodiments for the computer also constitutes the present invention.

  Further, means for supplying the above program to a computer, for example, a recording medium storing such a program constitutes the present invention. As a recording medium for storing the program code, for example, a flexible disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a magnetic tape, a nonvolatile memory card, a ROM, or the like can be used.

It is a figure which shows schematic structure of the automatic dispensing apparatus by which the nozzle apparatus of this embodiment is mounted. It is a figure which shows the structure of the nozzle apparatus of this embodiment. It is a figure which shows the structural example of a fitting detection part. It is a characteristic view which shows the relationship between the amount of contraction of the coil spring for fitting detection, and fitting pressure. It is a flowchart for demonstrating the processing operation at the time of mounting | wearing of the nozzle chip | tip in the nozzle apparatus of this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Nozzle apparatus 101 Nozzle base 102 Nozzle chip 103 Support frame 104 Movable body 200 Control part 300 XYZ drive part 400 Syringe pump 500 Pump drive part 600 Fitting detection part 601 Rod member 602 Coil spring 603 Detected part 604 Diffraction grating 605 Projection part 606 Light-receiving unit 607 One-dimensional PSD (position detection element)
608 Emitter 609 Slit

Claims (3)

A nozzle device configured to mount the nozzle tip on the nozzle base by lowering the nozzle base toward the nozzle tip for sucking and discharging liquid,
When mounting the nozzle tip, a movable body that is displaced according to the mounting force;
An elastic member that urges an elastic force against the displacement of the movable body;
A nozzle device comprising: detecting means for detecting a displacement amount of the movable body.   The nozzle device according to claim 1, wherein the detection unit detects a displacement amount of the movable body by a non-contact method. A control device for controlling the nozzle device according to claim 1 or 2,
A control device for a nozzle device, comprising: control means for stopping the descent of the nozzle device when a displacement detected by the detection means reaches a set value.

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