JP2020062245A - Syringe inspection device - Google Patents

Abstract

To provide a syringe inspection device having high measurement accuracy.SOLUTION: A syringe inspection device includes: a cylindrical body receiving part 3 for receiving a cylindrical body 1 so as to measure a sucking/discharging amount of liquid using a syringe S having the cylindrical body 1 and a plunger 2; a position decision part 32 coming in contact with a flange 13; a measurement part 41 for measuring a position of a measurement point 21 disposed in a part of the plunger 2; and a calculation part 42 for previously storing as basic information, positional information obtained by setting the plunger 2 to the cylindrical body 1 as a first position P1 and a second position P2, and a basic volume Vα of a storage chamber R regulated by the first position P1 and the second position P2. The device measures by the measurement part 41 two different positions of the plunger 2 before and after the operation when measuring a sucking/discharging amount of liquid, and calculates a movement distance for calculation of the plunger 2, and based on the movement distance for calculation and the basic information, the calculation part 42 calculates a sucking/discharging amount of liquid by the syringe S.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a syringe inspector that measures the amount of collected liquid based on a change in the volume of a syringe.

  Conventionally, as such a syringe inspector, for example, there is one described in Patent Document 1 below.

  This syringe inspector installs a cylinder on which a scale is displayed on the mounting portion, measures the position of the end of the plunger inserted in the cylinder by the distance measuring unit, and measures the volume of the liquid collected in the syringe. It is a thing.

  In this inspection device, the maximum distance Lmax between the end of the plunger and the distance measuring unit when the plunger is pushed into the cylinder, and the end of the plunger and the distance measuring unit when the plunger is pulled out to the maximum from the cylinder. And the minimum distance Lmin between them is stored. The volume of the liquid collected in the plunger can also be stored. For example, when the plunger is at the minimum distance Lmin, the volume of the liquid collected inside the cylinder is 35 ml.

When collecting a predetermined amount of liquid, the plunger is positioned between the maximum distance Lmax and the minimum distance Lmin, and the measured distance L between the end of the plunger and the distance measuring unit at that time is measured. Subsequently, the moving distance (Lmax-L) of the plunger is obtained, and using the value of 35 ml and the difference (Lmax-Lmin) of the distance stored in advance,
35: (Lmax-Lmin) = X: (Lmax-L)
The liquid collection amount is calculated based on the following relational expression.

Patent No. 6351192

  In the above-mentioned publicly known document, the value of (Lmax-L) is calculated every time the amount of collected liquid is measured. The Lmax value used here is the one initially stored according to the type of syringe and is unchanged in principle. However, there are some individual differences in the shape and size of the syringe used for each measurement, although they are of the same type. Therefore, when the common Lmax value is used as in the conventional technique, the value of (Lmax-L) also includes a predetermined error.

  As described above, in the above-mentioned conventional technique, there is a limit in accurately measuring the amount of collected liquid, and a syringe inspector with higher measurement accuracy is required.

(Characteristic composition)
The characteristic configuration of the syringe inspection device according to the present invention is
A tubular body having a liquid inlet / outlet formed at one end and an opening and a flange surrounding the opening at the other end,
In order to measure the suction and discharge amount of the liquid using a syringe that reciprocates in a state of being inserted in the cylindrical body and has a plunger that forms the liquid storage chamber with the cylindrical body,
A tubular body receiving portion for receiving the tubular body,
A position determining portion that contacts the flange;
A measuring unit for measuring the position of the measuring point provided in a part of the plunger,
Position information obtained by setting the plunger at a first position and a second position with respect to the cylindrical body, and a reference volume of the storage chamber defined by the first position and the second position And a calculation unit stored in advance as basic information,
When measuring the amount of suction and discharge of the liquid, two different positions before and after the operation of the plunger are measured by the measuring unit to calculate a moving distance for calculation of the plunger,
The arithmetic unit is configured to calculate the suction and discharge amount of the liquid by the syringe based on the arithmetic movement distance and the basic information.

(effect)
In the syringe inspection device of this configuration, when measuring the amount of sucked and discharged liquid, the position of the plunger before and after the suction operation or before and after the discharge operation is measured by the measuring unit. Since the error in the inner diameter of the cylindrical body is usually small, the accuracy of measuring the amount of sucked and discharged liquid is significantly improved by knowing the moving distance of the plunger.

  The two measurement positions of the plunger may be positions where the tip of the plunger is away from the inner part of the cylinder. However, when a certain amount of drug solution is sucked and separated by a syringe, the position of the plunger is measured while the plunger is pressed against the back of the cylinder, and the position of the plunger is measured after sucking a predetermined amount of drug solution. Is good. By doing so, when the liquid medicine is discharged, it is only necessary to push the plunger to the inner part of the cylinder, and the labor of adjusting the pushing position of the plunger is omitted.

(Characteristic composition)
In the syringe inspector according to the present invention, it is convenient if the basic information includes a sampling amount conversion coefficient that is a constant obtained by dividing the reference volume by the distance between the first position and the second position. .

(effect)
By storing the sampling amount conversion coefficient, which is a constant, as the basic information as in this configuration, the arithmetic expression based on the movement amount of the plunger is simplified, and the arithmetic processing becomes faster. Therefore, the work efficiency of collecting the amount of the liquid medicine is improved.

(Characteristic composition)
In the syringe inspector according to the present invention, the tubular body receiving portion has an inclination angle, the position determining portion is a groove portion into which a part of the flange can be inserted, and a part of the surface of the flange is the It can be configured to come into contact with the wall surface of the groove portion due to the inclination angle.

(effect)
With this configuration in which the position of the cylinder is determined by using the inclination angle of the cylinder receiving portion, the installation position of the cylinder can be accurately determined without complicating the configuration of the syringe inspector. Therefore, a syringe inspector with high measurement accuracy can be obtained while realizing cost reduction.

(Characteristic composition)
In the syringe inspector according to the present invention, it is convenient that the cylindrical body receiving portion is attached to the base portion via a shaft support portion whose tilt angle can be set.

(effect)
By making it possible to change the angle of the cylinder receiving part, the installation position of the cylinder can be reliably determined by using gravity, and the cylinder can be installed and removed easily by the operator. The attitude of the receiving portion can be arbitrarily determined. Therefore, the collection efficiency of the drug solution is further improved.

Perspective view showing the appearance of a syringe inspection device Explanatory drawing which shows the aspect of the standard measurement of a syringe inspection device. Explanatory drawing which shows the measurement aspect of a syringe inspection device

[First Embodiment]
(Overview)
The syringe inspecting device M (hereinafter, referred to as “inspecting device M”) of the present invention measures the amount of a liquid such as a drug solution collected based on the position change of the plunger 2 provided in the syringe S. Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. 1 is a perspective view showing the appearance of the inspector M, FIG. 2 is an explanatory view showing a mode of reference measurement of the inspector M, and FIG. 3 is an explanatory view showing a measuring mode of the inspector M. is there.

(Syringe)
As shown in FIGS. 1 to 3, the syringe S has a general shape. The syringe S has a cylindrical body 1, and has an inlet / outlet 11 for sucking / discharging a liquid formed at one end, and an opening 12 and a flange 13 surrounding the opening 12 at the other end. The plunger 2 is reciprocally inserted into the cylinder 1 so that the inner surface of the cylinder 1 and the end surface of the plunger 2 form a liquid storage chamber R.

  For the convenience of mounting the syringe S on the inspection device M, a plurality of types having a predetermined size are used. In this inspection device M, for example, a syringe S having a liquid sampling amount of 1 mL and a syringe S having a liquid sampling amount of 2.5 mL can be used.

(Cylinder receiving part / position determination part)
As shown in FIGS. 1 to 3, the inspector M has a tubular body receiving portion 3 that receives the tubular body 1. The tubular body receiving portion 3 includes an abutting portion 31 that individually abuts on the distal end portion and the proximal end portion of the tubular body 1 so that the installation posture of the tubular body 1 is stable. Further, each of the contact portions 31 is configured, for example, in a V shape so as to contact the curved surface of the cylindrical body 1 in a stable state.

  Further, the cylinder body receiving portion 3 is formed with a position determining portion 32 that determines the installation position of the cylinder body 1. The position determination part 32 is, for example, a groove part 32 a provided so that a part of the flange 13 can be inserted. A specific part of the flange 13 is brought into contact with the inner surface of the groove 32a, and the installation position of the tubular body 1 is determined along the longitudinal direction X of the tubular body 1.

  In order to set the installation position of the tubular body 1 more accurately, it is preferable to incline the tubular body receiving portion 3 as shown in FIG. 1 so that the flange 13 is always in contact with one surface of the groove portion 32a. Since the tubular body receiving portion 3 is formed integrally with the inspector body M1, in the present embodiment, the inspector body M1 is provided with the shaft support portion M2, and the shaft support portion M2 is provided with the rotatable base portion M3. There is. Thereby, the inclination posture of the cylindrical body receiving portion 3 can be set appropriately.

  A cylindrical outer peripheral surface M3a is provided at an end of the base M3 connected to the shaft support M2. Further, the outer peripheral surface M3a is provided with a plurality of recesses M3b which are recessed in the direction orthogonal to the rotation axis Y of the shaft support M2 along the circumferential direction. An engaging member M4 that is biased to project toward the rotation axis Y in a direction orthogonal to the rotation axis Y is provided on one of the shaft support portions M2.

  When the user applies a force to the inspector body M1 so as to change the angle of the cylindrical body receiving portion 3, the engaging member M4 repeatedly engages and disengages with each of the plurality of recesses M3b, and the inspector body M1 is preferred. Set to an angle. By appropriately setting the angle of the tubular body receiving portion 3, the flange 13 of the tubular body 1 is always in contact with one surface of the groove portion 32a due to gravity, and the tubular body 1 is accurately positioned with respect to the tubular body receiving portion 3. It Moreover, by changing the inclination of the tubular body receiving portion 3, the user can easily read the scale provided on the surface of the tubular body 1.

  An external terminal 52 such as a power switch 51 and a USB terminal is provided on the outer surface of the inspector body M1.

(Measurement section)
The inspector main body M1 is provided with a measuring section 41 that measures the position of the measuring point 21 with the end surface on the protruding side of the plunger 2 as the measuring point 21, for example. In the measuring unit 41, an irradiation unit 41a that irradiates the measuring point 21 of the plunger 2 with the measuring light and a light receiving unit 41b that receives the measuring light reflected at the measuring point 21 are provided on the extension of the longitudinal direction X of the plunger 2. It is provided.

  The measurement is started using the foot switch 55 connected to the inspector body M1. For example, each time the foot switch 55 is operated, measurement light is emitted from the irradiation unit 41a.

(Calculator)
The volume of the liquid collected in the syringe S is calculated by the calculation unit 42 based on the numerical values obtained by the measurement unit 41. The calculation unit 42 is configured by, for example, a calculation chip that is specially configured in advance so that calculation according to a predetermined procedure is performed, and is incorporated in the inspector body M1.

  The calculation unit 42 stores basic information for calculating the volume of the collected liquid. The basic information includes position information related to the position of the plunger 2 and a reference volume related to the volume of liquid sucked and discharged into the inside of the cylinder 1 by the operation of the plunger 2. Acquisition of these basic information will be described with reference to FIG.

  In the present embodiment, as the position information, first, the first position information L1 when the plunger 2 is at the first position P1 in which the plunger 2 is pushed deep into the cylindrical body 1, and the plunger 2 is approximately the maximum distance from the first position P1. The second position information L2 when the second position P2 is pulled out is provided. The first position information L1 and the second position information L2 are initially measured only once in order to obtain position information about the syringe S of the specific type. From the first position information L1 and the second position information L2, the distance between the first position P1 and the second position P2 is stored as the reference distance Lα. This reference distance Lα is also one of the position information.

  If the reference distance Lα is stored in the calculation unit 42, the storage of the values themselves of the first position information L1 and the second position information L2 can be omitted. Further, even after the reference distance Lα is once stored, when the first position information L1 and the second position information L2 are measured again, the reference distance Lα is updated.

  On the other hand, as the reference volume, the volume V defined by the storage chamber R of the tubular body 1 is stored as the reference volume Vα when the plunger 2 moves from the first position P1 to the second position P2. The reference volume Vα is obtained by the user reading the scale of the cylinder 1 when the plunger 2 is at the first position P1 and the second position P2, and is calculated from the difference between the two. Input to the calculation unit 42 is made from an input unit 54 such as a personal computer or a keyboard connected to the inspector body M1.

Further, in the present embodiment, in order to facilitate the calculation for each measurement, the collection amount conversion coefficient Z (I formula) that is a constant obtained by dividing the reference volume Vα by the reference distance Lα is stored as basic information.
Sampling amount conversion coefficient Z = Vα / Lα ... I formula Incidentally, the reference volume Vα, the reference distance Lα, and the sampling amount conversion coefficient Z are stored in the computing unit 42 for each size of the syringe S to be used.

  The reason why the reference distance Lα based on the moving distance of the plunger 2 and the reference volume Vα which is the volume change of the cylinder 1 at that time are used in this way is as follows. Usually, the shape of the syringe S of the same model has individual differences such as manufacturing errors, and for example, some errors may be included when only the first position information L1 is viewed. However, since the inner surface shape of the cylinder 1 is manufactured so as to be within a certain error range, the correlation between the moving distance of the plunger 2 and the volume of the liquid sucked into the cylinder 1 has a certain accuracy. . Therefore, for example, rather than associating the absolute position of the plunger 2 with the intake / exhaust volume, the measurement accuracy can be improved by using the sampling amount conversion coefficient Z as in the present configuration.

  Each of the basic information is stored in the non-volatile memory of the calculation unit 42. The calculated value may be stored as the collection amount conversion coefficient Z, or the reference volume Vα and the reference distance Lα may be stored as a value that substantially indicates the collection amount conversion coefficient Z, and (Vα / The mathematical expression Lα) may be used.

(Measurement procedure)
Next, a measurement mode at each time of collecting the liquid will be described with reference to FIG. For example, when measuring the amount of collected liquid, two pieces of position information of the plunger 2 before and after collecting the liquid, that is, first measurement position information La at the first measurement position Pa and second position information at the second measurement position Pb. The measurement position information Lb is measured by the measuring unit 41, and the calculation movement distance Lβ (formula II) of the plunger 2 is calculated.
Calculation moving distance Lβ = La−Lb (II) The operation of the syringe S is a manual operation of the user, but at this time, air and bubbles should not be mixed into the syringe S.

  In most cases, the first measurement position Pa is the same as the position where the plunger 2 is pushed to the inner part of the cylindrical body 1. This position is substantially uniquely determined because the rear end of the plunger 2 abuts on the rear part of the cylindrical body 1. However, when manufacturing the syringe S, a shape error may occur for each individual. The shape of the plunger 2 is smaller than that of the tubular body 1 and longer than the tubular body 1. Therefore, a shape error is more likely to occur than in the cylindrical body 1 such as the resin of the forming material contracting.

  The shape of the tip end of the plunger 2 that comes into close contact with the inner surface of the cylindrical body 1 is particularly important, but even if there is a shape error in the elongated portion extending to the other end, it does not affect normal liquid sampling. Therefore, in the main inspection device M that measures the measurement point 21 on the end face of the plunger 2, the position of the end face is measured every time even when the plunger 2 is pushed into the cylindrical body 1. With respect to the position of the other end face, since the sampling amount conversion coefficient Z is used, the measurement for each time is omitted. By such measurement, the measurement efficiency and the measurement accuracy of the liquid sampling amount are improved.

The sampling volume A (formula III) of the sampled liquid is calculated based on the calculation movement distance Lβ thus obtained and the sampling amount conversion coefficient Z.
Sampling volume A = Z x Lβ ... Formula III

The specific procedure of measurement is as follows.
When collecting the liquid, the user first steps on the foot switch 55 connected to the inspection device M. Since "Please set an empty syringe" is displayed on the display window 53 of the control unit 50 connected to the inspector M, the plunger 2 is pushed into the cylinder body 1 and the flange 13 of the cylinder body 1 is inserted into the groove 32a. The cylindrical body 1 is placed on the cylindrical body receiving portion 3 while being inserted into the. "Measuring" is displayed on the display window 53, the measurement light is emitted from the irradiation unit 41a of the measurement unit 41 toward the measurement point 21 of the plunger 2, and the reflected measurement light is returned to the light reception unit 41b.

  As a result, the first measurement position information La at which the plunger 2 is substantially at the zero scale position of the cylinder 1 is measured. The first measurement position information La stored in the calculation unit 42 is updated with this measurement result. It is about 3 seconds after the foot switch 55 is pressed until the measurement of the first measurement position information La is completed.

  If the syringe S is not set, the display window 53 displays "Measurement failure". Further, the measurement of the first measurement position information La may be performed multiple times.

  Next, the message "Please set the syringe after performing mixed injection" is displayed on the display window 53, so that the user sucks a predetermined amount of the liquid into the syringe S, and the cylinder 1 is transferred to the cylinder receiving portion 3. Reset it. When the resetting is completed, the foot switch 55 is pushed. “Measuring” is displayed on the display window 53, and the second measurement position information Lb of the plunger 2 is measured within about 3 seconds. The measurement of the second measurement position information Lb may be performed multiple times.

  The calculation unit 42 calculates the calculation movement distance Lβ from the first measurement position information La and the second measurement position information Lb, and calculates the liquid collection amount based on the collection amount conversion coefficient Z stored in advance. The result is displayed on the display window 53.

  A predetermined mixed injection amount for the liquid to be collected may be stored in the calculation unit 42. In that case, a numerical value is stored according to the syringe S to be used. After the measurement, if the amount of collected liquid is within the specified range, “Measurement completed” or the like is displayed on the display window 53, and the measurement operation is finished. On the other hand, if the measured value is out of the specified range, it is possible to prompt the user to re-measure by displaying "Please perform the mixed injection again and set the syringe".

[Other Embodiments]
In the above embodiment, in order to measure the position of the plunger 2, the measurement light is reflected at the end of the plunger 2. However, in addition to this, for example, the position of the plunger 2 is photographed and the position is determined by image processing. The measurement may be performed. Further, a plurality of light receiving elements are arranged in the cylindrical body receiving portion 3 along the moving direction of the plunger 2, and light is emitted at a right angle to the longitudinal direction X of the plunger 2 so that the light is emitted by the plunger 2. It may be a device that measures a blocked position.

  Further, in the above-described embodiment, since the posture of the plunger 2 is tilted when measuring the position of the plunger 2, it is possible that the plunger 2 slightly moves due to gravity during the measurement. Therefore, it is assumed that a single measurement is performed a plurality of times in succession, and if a certain error occurs between the measurement results, an error is displayed in the display window 53 or an alarm is output from a speaker provided separately. It may be good to make a sound.

  The technique according to the present invention can be widely applied to a syringe inspector for measuring the volume of a sampled liquid by measuring the position of a plunger.

DESCRIPTION OF SYMBOLS 1 Cylinder 11 Suction / exhaust 12 Opening 13 Flange 2 Plunger 21 Measuring point 3 Cylinder receiving part 32a Groove 32 Position determining part 41 Measuring part 42 Computing part M Syringe inspector M2 Shaft support M3 Base part P1 First position P2 2 position R Storage chamber S Syringe Vα Reference volume Z Sampling amount conversion coefficient

Claims (4)

A tubular body having a liquid inlet / outlet formed at one end and an opening and a flange surrounding the opening at the other end,
In order to measure the suction and discharge amount of the liquid using a syringe that reciprocates in a state of being inserted in the cylindrical body, and a plunger that forms a storage chamber for the liquid with the cylindrical body,
A tubular body receiving portion for receiving the tubular body,
A position determining portion that contacts the flange;
A measuring unit for measuring the position of the measuring point provided in a part of the plunger,
The positional information obtained by setting the plunger at the first position and the second position with respect to the tubular body, and the reference volume of the storage chamber defined by the first position and the second position, And a calculation unit stored in advance as basic information,
When measuring the suction and discharge amount of the liquid, two different positions before and after the operation of the plunger are measured by the measuring unit to calculate a moving distance for calculation of the plunger,
A syringe inspector, in which the arithmetic unit calculates the suction and discharge amount of the liquid by the syringe based on the arithmetic movement distance and the basic information.   The syringe inspection device according to claim 1, wherein the basic information includes a sampling amount conversion coefficient that is a constant obtained by dividing the reference volume by the distance between the first position and the second position.   The tubular body receiving portion has an inclination angle, the position determining portion is a groove portion into which a part of the flange can be inserted, and a part of the surface of the flange is a wall surface of the groove portion due to the inclination angle. The syringe inspector according to claim 1 or 2, which is configured to come into contact with the syringe.   The syringe inspecting device according to claim 3, wherein the cylindrical body receiving portion is attached to a base portion via a shaft support portion capable of setting the inclination angle.

Images