JPH09184819A - Concentration-measuring apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a concentration-measuring apparatus which can remarkably simplify setting and discharging operational procedures for a sensor. SOLUTION: A cartridge 2 storing many sheets of sensors 1 in a state urged upward is set in a main body 3 of the concentration-measuring apparatus. The uppermost sensor 1 is pressed by a pressing member 4 to project from the main body 3. A cam member 4b moving following the pressing member 4 and a lever member 4d engaged with the cam member 4b thereby restricting a forward/rearward movement of the cam member 4b are provided in order to set a forward movement length and a rearward movement length of the pressing member 4 to press out approximately half a length of the sensor 1 when the pressing member 4 moves forward at the first time and nearly the entire length of the sensor when the pressing member 4 moves forward at the second time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a concentration measuring device, and more specifically, it relates to a substance which is produced or eliminated by oxidizing or reducing a substance to be measured in the presence of a physiologically active substance. The present invention relates to a concentration measuring device which inputs an electric signal corresponding to a quantity from an electrode of a sensor and outputs a concentration measuring signal based on the electric signal.

[0002]

2. Description of the Related Art Conventionally, a membrane comprising a physiologically active substance such as an enzyme immobilized on an upper surface of an electrode body having a working electrode, a counter electrode and an optional reference electrode (hereinafter simply referred to as immobilized enzyme membrane). It has been proposed to measure the concentration of a target substance in a solution using a sensor provided with the same. If glucose oxidase is employed as the physiologically active substance, it can be applied to the measurement of the concentration of sugar.

[0003] However, when measuring the sugar concentration in blood, the blood glucose level is measured using the sensor having the above-described structure because of the large amount of interfering substances such as blood cells in the blood. Is repeatedly measured, there is a high possibility that the measured values after the second time will be inaccurate. In particular, in the case of a blood glucose level measuring device that is intended for use in ordinary households, in order to prevent the measurement value from being inaccurate, a sensor is mounted in advance and the blood glucose level is measured. In order to perform measurement, it is instructed that a new sensor should be attached to the blood glucose level measuring device.

[0004] In this way, the inconvenience of repeatedly measuring the blood sugar level without replacing the sensor can be prevented.

[0005]

However, when the above-described blood sugar level measuring device is employed, it is necessary to take out the individually mounted sensor and set it in the blood sugar level measuring device before measuring the blood sugar level. In addition to this, it is necessary to take out the used sensor from the blood sugar level measuring device after the measurement of the blood sugar level is completed.

[0006] Since the sensor is remarkably miniaturized in order to reduce the required amount of blood as much as possible, there is a disadvantage that the above operation is difficult and troublesome. In addition, there is a possibility that the sensor is not set correctly, and in this case, there is a disadvantage that the output signal from the sensor cannot be taken out and the blood glucose level cannot be measured.

Although only the blood sugar level measuring device has been described above, the same disadvantages may occur in a concentration measuring device for measuring the concentration of another substance as long as the sensor needs to be replaced for each measurement. There is.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and can greatly simplify the operation of setting a sensor before measurement and taking out the sensor after measurement. It is an object of the present invention to provide a concentration measuring device capable of accurately setting the concentration.

[0009]

According to a first aspect of the present invention, a concentration measuring device outputs a concentration measuring signal by inputting an output signal from the cartridge and a cartridge in which a plurality of concentration measuring sensors are stacked and accommodated. A sensor having a concentration measuring device main body having a signal processing unit, the cartridge being removably attached to the concentration measuring device main body, and the cartridge exerting a pressing force to move the sensor toward the opening of the cartridge. A pressing member that has an urging member, in which the concentration measuring device body pushes the sensor located at the opening of the cartridge from the concentration measuring device body, and a pressing member urging member that urges the pressing member in a direction opposite to the pushing direction. A cam member, and an engaging member that engages with the cam member and controls the returning position of the pressing member by the pressing member urging member. One of the members is provided integrally with the pressing member, and the cam member sets the position of the pressing member at the time of the first pressing so that the sensor pushes out the sensor by a predetermined length shorter than its entire length. The returning position of the pressing member at the time of releasing the pressing force is set so as to prevent movement of the second sensor by the sensor urging means, and the position at the time of the second pressing of the pressing member is set to the sensor over almost its entire length. It is set so as to be pushed out from the main body of the measuring device, and the returning position of the pressing member at the time of releasing the pressing force for the second time is set so as to allow the movement of the second sensor by the sensor urging means.

[0010]

According to the first aspect of the present invention, when the cartridge is mounted on the main body of the concentration measuring device, a large number of sensors in the cartridge are urged toward the opening of the cartridge by the sensor urging member. I have. In this state, if the pressing member is moved forward against the pressing member urging member, the pressing member can move in the direction in which the first sensor pushes out the first sensor from the concentration measuring device main body. Since this movement of the pressing member is the first time, the sensor is pushed out by the cam member and the engaging member by a predetermined length shorter than its entire length. The measurement target solution (solution containing the measurement target substance) can be easily spotted on the pushed sensor. Then, a signal corresponding to the concentration of the substance to be measured is output from the sensor, and this signal is guided to the signal processing unit included in the main body of the concentration measuring device to output the concentration measurement signal. When the pressing force applied to the pressing member is released, the cam member and the engaging member limit the return distance of the pressing member by the pressing member urging member, so that the second sensor urges the sensor. It is possible to reliably prevent the member from being moved (the second sensor is in a state in which it can be pushed out by the pressing member).

After the density measurement, if the pressing member is moved back again against the pressing member biasing member, the cam member and the engaging member cause the pressing member to measure the density of the first sensor further. The sensor can be pushed out of the device body and dropped from the concentration measuring device body. After that, the pressing force on the pressing member may be released, and the pressing member can be returned to the initial state by the cam member and the engaging member and by the urging force of the pressing member urging member.
Thereafter, the remaining sensors are moved toward the opening of the cartridge by the sensor urging member, so that the second sensor can be pressed by the pressing member.

Therefore, by moving the pressing member once, the sensor can be made to protrude from the main body of the concentration measuring device to the set position for the concentration measurement.
The sensor used can be dropped from the main body of the concentration measuring device by moving the pressing member forward again. When the pressing force on the pressing member is released, the pressing member can be moved back to the initial state. As a result, the work for setting and taking out the sensor can be remarkably simplified, and the setting state of the sensor can be set accurately, and the occurrence of poor electrical connection and the like can be prevented.

[0013]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a perspective view of a main part showing an embodiment of the concentration measuring electrode of the present invention. This concentration measuring device has a cartridge 2 for accommodating a large number of flat sensors 1 in a stacked state, and a main body 3 of the concentration measuring device.

As shown in the plan view of FIG. 2, the sensor 1 has a pentagonal shape (a shape obtained by cutting off one short side corner of a rectangle having a predetermined length) and is electrically insulating with a predetermined thickness. At a predetermined position near the tip of the thin plate 1a (close to the excised portion),
The reference electrode 1b, the counter electrode 1c, the working electrode 1d, the counter electrode 1c, the working electrode 1d, and the counter electrode 1c are formed close to each other in this order from the front end side, and the reference electrode lead terminal is provided at a predetermined position near the rear end. 1b1, a counter electrode lead terminal 1c1, a working electrode lead terminal 1d1, and a working electrode lead terminal 1d1 are formed. These lead terminals are formed in this order in the width direction of the thin plate 1a. Then, the reference electrode 1b and the reference electrode lead terminal 1b1 are electrically connected by the reference electrode wiring pattern 1b2, and all the counter electrodes 1c and the counter electrode lead terminal 1c1 are connected to each other by the counter electrode wiring pattern. 1c2 electrically connects each working electrode 1d to the corresponding working electrode lead-out terminal 1d1 by a working electrode wiring pattern 1d2. Further, the reference electrode 1b, the counter electrode 1c, the working electrode 1d, the counter electrode 1c, the working electrode 1d, the counter electrode 1c, and an immobilized enzyme membrane (not shown) are provided so as to cover the gaps between them, Electrode wiring pattern 1b2, counter electrode wiring pattern 1c2, working electrode wiring pattern 1
A resist layer (not shown) is provided so as to cover d2 and these gaps. However, preferably, a permselective membrane for selectively permeating a reaction product substance or a reaction disappearance substance is provided on the lower surface of the immobilized enzyme membrane.

The cartridge 2 accommodates a large number of the sensors 1 shown in FIG. 2 in a stacked state, and has an opening 2a for sending out the sensor at a predetermined position on one end side thereof. An opening 2b that allows a pressing member, which will be described later, to enter is provided at a position facing each other. Then, inside the cartridge 2, a coil spring 2c that applies a biasing force to move the many sensors 1 toward the end side where the openings 2a and 2b are formed, a rod-shaped body 2d that guides the coil spring 2c, and A biasing force transmission member 2e that transmits a substantially uniform biasing force to the lower surface of the sensor 1 by being pressed by the coil spring 2c is provided.

The concentration measuring device main body 3 accommodates a battery 3b as a DC power source inside a casing 3a having a substantially rectangular parallelepiped shape as a whole, and a partition wall 3d near the other end. To form a cartridge housing space 3c which is partitioned from other parts. The cartridge housing space 3c allows the cartridge 1 to be loaded and unloaded with the lid 3e provided at the bottom (lower side in FIG. 1) of the casing 3a opened. In the outer wall 3f and the partition wall 3d of the cartridge housing space 3c, the openings 3g and 3 that face the openings 2a and 2b of the cartridge 1 in the state where the cartridge 1 is housed, respectively.
h is formed. And the cartridge housing space 3
A contact member accommodation space 3i is formed immediately above c, and four contact member 3 accommodated in this contact member accommodation space 3i.
j projects downward from the contact member accommodation space 3i, penetrates the upper wall 3k of the cartridge accommodation space 3c, and slightly penetrates into the cartridge accommodation space 3c. These four contact members 3j are used as reference electrode lead terminals 1 of the sensor 1.
b1, counter electrode lead-out terminal 1c1, working electrode lead-out terminal 1d1, and working electrode lead-out terminal 1d1 are respectively brought into contact with each other to achieve electrical connection. Also, these four contact members 3j
Is configured to come into contact with each lead-out terminal when the sensor 1 is pushed out by a pressing member described later for a predetermined length shorter than its entire length (see also FIG. 3). Further, a signal processing unit (not shown) for receiving an output signal from the sensor 1 by being electrically connected to the four contact members 3j is provided. The signal processing unit takes in the output signal from the sensor 1 and detects, for example, the maximum value of the differential value of the output signal, and determines the concentration of the substance to be measured based on this maximum value and a preset calibration curve. And outputs the indicated concentration measurement signal.

In the main body 3 of the concentration measuring device, a pressing member 4 for pushing out only the uppermost sensor 1 is reciprocally slidable at a predetermined position between the battery 3b and the cartridge housing space 3c. The pressing member 4 is a casing 3a.
And a cam member 4b located inside the casing 3a while integrally having a pressing operation member 4a protruding from the casing.
Have integrally. Further, an urging spring 4c for applying an urging force to move the pressing member 4 in a direction away from the cartridge accommodating space 3c is provided between a predetermined position of the pressing member 4 and a predetermined position of the casing 3a. Further, a lever member 4d which engages with the cam member 4b and regulates the forward and backward movement distances of the pressing member 4 is swingably provided at a predetermined position of the casing 3a.

The cam member 4b has a cam groove 4e and is engaged with a protruding shaft member 4d1 provided at the tip of the lever member 4d (see also FIG. 4). The cam groove 4e rotates the lever member 4d downward and then upward with the forward movement of the pressing member 4, and the pressing member 4 causes the sensor 1 to rotate.
A predetermined length shorter than the total length of (about half of the total length)
Only the forward movement, the protruding shaft member 4 of the lever member 4d
The first cam groove portion 4e1 that abuts against d1 and blocks the forward movement of the pressing member 4, and the forward movement is blocked by the first cam groove portion 4e1. Then, the lever member 4d is rotated upward, and when the pressing member 4 is returned by a predetermined length shorter than the forward movement length, the lever member 4d collides with the protruding shaft member 4d1 of the lever member 4d and the pressing member 4 is returned. Second cam groove portion 4e2 for preventing movement
When the pressing member 4 is moved forward again, after the lever member 4d is rotated upward with the forward movement of the pressing member 4,
The lever member 4d is kept in a state in which it is kept in the uppermost rotated state and the pressing member 4 is moved forward by a predetermined length substantially equal to the entire length of the sensor 1 with respect to the initial position.
The third cam groove portion 4e3 that abuts against the protruding shaft member 4d1 to prevent the forward movement of the pressing member 4, and the forward movement is blocked by the third cam groove portion 4e3, and then the pressing member 4 is pressed by the biasing spring 4c. When the lever member 4d is moved backward, the lever member 4d is kept rotated in the uppermost position and then rotated downward, and the pressing member 4 is returned to the initial position. The pressing member 4 is abutted against the member 4d1.
And a fourth cam groove portion 4e4 for preventing the backward movement of the.

The first cam groove portion 4e1 to the fourth cam groove portion 4e4 are continuous in this order, and
End of fourth cam groove 4e4 and first cam groove 4e1
Of the pressing member 4 by repeating the
Forward and backward movements can be performed.
The operation of the concentration measuring device having the above configuration is as follows.
However, in the following, a case where glucose oxidase is used as an enzyme and a blood glucose level is measured will be described as an example.

First, the lid 3e of the casing 3a is opened to accommodate the cartridge 2 in which a large number of sensors 1 are stacked in the cartridge accommodation space 3c, and then the lid 3e is closed to close the cartridge 2 therein. To prevent the falling off. In this state, since the pressing member 4 is not operated at all, the terminal end portion of the fourth cam groove portion 4e4 of the cam groove 4e is the protruding shaft member 4d1 of the lever member 4d.
It is a state where it hits (see FIG. 5).

When measuring the blood glucose level, first, the pressing member 4a is pressed to move the pressing member 4 forward. In this case, the cam member 4b also moves forward with the forward movement of the pressing member 4, and the protruding shaft member 4d1 of the lever member 4c engages with the first cam groove portion 4e1. After being rotated downward, it is rotated upward so that the first cam groove portion 4e1 finally moves the protruding shaft member 4d of the lever member 4c.
1, and the forward movement of the pressing member 4 is blocked. Due to this forward movement of the pressing member 4, the tip end of the pressing member 4 has an opening 3h,
2b in this order to enter the inside of the cartridge 2,
The uppermost (first) sensor 1 is pressed to open the openings 2a, 3
g is projected in this order from the casing 3a. However, the protruding length of the sensor 1 is a predetermined length shorter than the entire length, and the pressing force acts on the portion of the sensor 1 remaining in the cartridge 2 by the coil spring 2c and the urging force transmitting member 2e. Therefore, the natural fall of the sensor 1 is reliably prevented. Of course, the tip of the sensor 1 (the portion including the reference electrode 1b, the counter electrode 1c, the working electrode 1d, and the portion covered with the immobilized enzyme membrane) is projected from the casing 3a.

Then, when the pressing force is released, the urging spring 4
The pressing member 4 is moved backward by c. However, the returning length in this case is such that the second cam groove portion 4e2 is the lever member 4c.
It is a length until it hits the protruding shaft member 4d1 and blocks the forward movement of the pressing member 4, and even if the pressing member 4 moves backward, the tip end portion of the pressing member 4 remains inside the cartridge 2. Therefore, the second sensor 1 is not pushed up (see FIG. 6).

In this state, the reference electrode lead-out terminal 1b1, the counter electrode lead-out terminal 1c1, the working electrode lead-out terminal 1d1, and the working electrode lead-out terminal 1d1 of the first sensor 1 are in contact with the four contact members 3j, respectively. Therefore, the blood glucose level can be measured by spotting the blood to be measured on the immobilized enzyme membrane. That is, glucose in blood is oxidized in the presence of glucose oxidase to generate gluconic acid and hydrogen peroxide. Hydrogen peroxide is oxidized because a predetermined bias voltage is applied between the working electrode 1d and the reference electrode 1b, and an electric signal accompanying the oxidation is generated by the working electrode 1d and the counter electrode 1c. Output from And
By supplying this electric signal to the signal processing unit through the corresponding contact member 3j, a blood glucose level measurement signal can be obtained.

Next, if the pressing member 4 is moved forward again,
The third cam groove portion 4e3 is the protruding shaft member 4d of the lever member 4c.
Since the pressing member 4 moves forward until it abuts 1 and blocks the forward movement, the first sensor 1 is almost completely attached to the casing 3a.
It can be made to project from and fall naturally (see FIG. 7). After that, the pressing force only needs to be released, and the biasing spring 4c causes the fourth cam groove portion 4e4 to move to the lever member 4.
The pressing member 4 is moved back until it hits the protruding shaft member 4d1 of c and prevents the pressing member 4 from moving forward. This state is the same as the initial state, and prepares for the next blood sugar level measurement.
However, in the cartridge 2, all the remaining sensors 1 are pushed up by the thickness of one sensor by the coil spring 2c and the urging force transmitting member 2e in response to the pressing member 4 being completely removed from the cartridge 2.

Therefore, the blood glucose level can be repeatedly measured by repeating the above operation. Further, as is apparent from the above description, the operation to be performed by the operator is only the pressing of the pressing member 4 and the release of the pressing force, and there is no need to set or take out the sensor 1 by hand. The operation can be significantly simplified. Further, since the set state of the sensor 1 is always constant, the electrical connection is reliably ensured.

Although the case where the blood glucose level is measured has been described above as an example, it can be applied to the measurement of the concentration of the measurement target substance other than glucose and the concentration of the measurement target substance in the solution other than blood. is there. However, in these cases, it is necessary to select a physiologically active substance such as an enzyme according to the substance to be measured. Further, although the case where the cam member 4b is provided integrally with the pressing member 4 and the lever member 4d is provided in the casing 3a has been described above, the cam groove 4e of the cam member 4b and the protruding shaft of the lever member 4d are described. Since it suffices that the relative position with respect to the member 4d1 changes, the lever member 4d is provided on the pressing member 4 and the cam member 4b is provided.
Even if the casing 3a is provided, the same effect can be obtained.

[0027]

As described above, according to the invention of claim 1, the sensor can be set and the sensor can be discharged in this order only by repeatedly pressing the pressing member and releasing the pressing force. As a result, There is a unique effect that the operation can be remarkably simplified and a reliable setting state of the sensor can be achieved.

[Brief description of the drawings]

FIG. 1 is a perspective view of a main part showing an embodiment of a concentration measuring device of the present invention.

FIG. 2 is a plan view of a sensor.

FIG. 3 is a vertical cross-sectional view showing an electrically connected state between a sensor and a contact member.

FIG. 4 is a transverse cross-sectional view showing an engagement state between a protruding shaft member of a lever member and a cam groove of a cam member.

5 is a vertical cross-sectional view showing an initial state of an internal mechanism of the concentration measuring device of FIG.

6 is a vertical cross-sectional view showing a concentration measurement state of an internal mechanism of the concentration measurement device of FIG.

7 is a vertical cross-sectional view showing a sensor discharge state of an internal mechanism of the concentration measuring device of FIG.

[Explanation of symbols]

 1 Sensor 2 Cartridge 2a, 2b Opening 2c Coil Spring 2e Energizing Force Transmission Member 3 Concentration Measuring Device Main Body 4 Pressing Member 4b Cam Member 4c Energizing Spring 4d Lever Member

Claims (1)

[Claims] 1. A cartridge (2) in which a plurality of sensors (1) for concentration measurement are stacked and accommodated, and a signal processing unit which outputs a concentration measurement signal by receiving an output signal from the sensor (1) as an input. A concentration measuring device body (3) having the same, the cartridge (2) is detachably attached to the concentration measuring device body (3), and the cartridge (2) mounts the sensor (1) on the cartridge (2). Sensor biasing members (2c) (2e) for exerting a pressing force to move them toward the openings (2a) (2b) of the
And a pressure member (4) for pushing the sensor (1) located in the openings (2a) (2b) of the cartridge (2) from the concentration measuring device body (3). , A pressing member urging member (4c) for urging the pressing member (4) in a direction opposite to the pushing direction, a cam member (4b), and a pressing member urging member (4c) engaged with the cam member (4b). ) And an engaging member (4d) for controlling the backward moving position of the pressing member (4) and the forward moving position of the pressing member (4) by the pressing force, and the cam member (4b) and the engaging member (4d). One of them is provided integrally with the pressing member (4), and the cam member (4b) determines the position of the first pressing member (4) when the pressing member (4) is pressed by the sensor (1) shorter than its entire length. It is set to push out from the concentration measuring device body (3) only for the length, and the first pressing force is released. The second sensor (1) of the sensor biasing means backward position of the pressing member (4) in (2
c) Set so as to prevent movement by (2e),
The position at the time of pressing the second pressing member is set so that the sensor (1) is pushed out from the concentration measuring device main body (3) over substantially the entire length thereof, and the pressing member (4) at the time of releasing the second pressing force.
Is set to allow the movement of the second sensor (1) by the sensor urging means (2c) (2e).