JPH10192402A - Transfusion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect the overload condition, the syringe come-off condition, and the negative pressure generating condition, respectively to give a signal, so as to produce an effect of enabling safe transfusion operation by providing a processing circuit for comparing an output value of a pressure sensor with plural separately reference values to generate a processing signal. SOLUTION: When a motor 7 of a driving mechanism is turned at a designated speed and in a designated direction, a slider 3 engaged with a feed screw 5 presses a sucker 2 at a designated speed in a designated direction to feed a liquid. Points 1, 2, 3 and 4 of pressure values are set in a comparing circuit 11 to be compared with the output of a pressure sensor 20, and processing signals corresponding to the respective conditions are output. For example, when the output of the pressure sensor 20 comes to the point 1, a signal of judging that a syringe is not set is sent, when it exceeds the point 3 and less than the point 4, a signal of judging the normal operation is sent, when it exceeds the point 4, a signal of judging the overload condition is sent, and when it comes to the point 2 or less, a signal of judging that negative pressure is applied to the sucker is sent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an infusion device,
More particularly, the present invention relates to a drive mechanism of an infusion device configured to send out liquid by pressing a suction rod of a syringe with a slider that operates linearly by a feed screw driven by a prime mover.

[0002]

2. Description of the Related Art There are many conventional infusion devices which have a feed screw driven by a prime mover, and which press a syringe sucker by a linearly movable slider engaged with the feed screw to send out liquid. An improved technique has been proposed. In particular, a configuration has been proposed in which the pressure applied to the sucker is detected by a slider in order to monitor the delivery state of the liquid, and a warning is issued by comparing the detected pressure with a reference value. -44
There is one disclosed in Japanese Patent Publication No. 390.

[0003]

The prior art described in the above-mentioned publication discloses a method in which a pressure sensor is provided at a position where the slider is pressed against the sucker, and the output of the sensor is compared with a plurality of reference values to generate an alarm. For safe infusion. " However, the configuration described in this publication has a configuration in which the end of the sucker abuts against the slider, as shown in FIG. In the case where the sucker is sucked in the direction of the syringe due to the external suction force acting on the syringe (negative pressure), the sucker moves away from the slider and cannot be injected. There is a problem that can not be. It is an object of the present invention to provide an infusion device provided with a detection device capable of detecting a negative pressure applied to the above-mentioned sucker.

[0004]

The infusion device according to the present invention has a holding arm for pressing and holding the flange of the sucker to the sucker receiving portion of the slider in a direction opposite to the direction of pressing the sucker.
And, a pressure sensor is provided in the sucker receiving portion of the slider,
A processing circuit for holding the collar portion of the sucker on the sucker receiving portion of the slider by the holding arm, and comparing the output value of the pressure sensor with a plurality of separately set reference values to generate a processing signal; It is comprised so that it may be provided.

[0005]

The construction of the present invention as described above has a holding arm that presses and holds the flange of the sucker to the sucker receiving portion of the slider in a direction opposite to the direction of pressing the sucker.
Even if a situation (negative pressure) occurs in which the sucker is sucked into the syringe with a force greater than the feed pressure acting on the sucker by the slider, the sucker is held by the slider and the The state of the negative pressure can be detected by comparing the output detected by the pressure sensor when the flange is held by the holding arm by the holding arm with the reference value.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an infusion device according to the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram showing the configuration of an infusion device according to the present invention, in which 1 is a syringe, 2 is a sucker housed in a syringe 1, 3 is a slider, 4 is a feed screw 5
, A feed screw, 6 a gear, 7 a motor, 8 a slit plate, 9 a photocoupler, 10 a pressure sensor, 11 a comparison circuit, 12 a motor drive circuit, 13
Denotes a CPU, and 14 denotes an encoder processing circuit. The infusion device shown in FIG. 1 has a syringe 1 attached to a body (not shown).
Is mounted, the feed screw 5 is rotated via the gear 6 by the rotation of the motor 7, and the slider 3 which is linearly driven by the carriage 4 which engages with the feed screw 5 keeps the sucker 2 housed in the syringe 1 constant. The suction device 2 is driven in the direction, and the liquid in the syringe 1 is sent out when the sucker 2 is pressed. Since the device shown is used to send a predetermined amount of a drug solution or the like to the human body at a predetermined speed, a detection device that constantly monitors the delivery state of the liquid and performs accurate infusion is necessary. Becomes

FIG. 2A to FIG. 2C are enlarged sectional views of a main part of the slider 3 shown in FIG. 1, and FIG. 2B shows a state in which the holding arm 30 to which the flange is not attached is opened, FIG. 2B shows a state in which the holding arm 30 is closed, and FIG.
, Respectively, are shown. The description of the driving mechanism of the holding arm 30 is omitted to avoid complication.

2A to 2C, 3 is a slider, 3-2 is a sucker receiving portion of the slider, 30 is a holding arm of a flange portion, 31 is a support shaft of the arm, and 32 is a return spring of the support shaft 31 of the arm. , 20 are pressure sensors, and 21 is a pressure transmitting unit.

2A and 2B, the pressure sensor 20
Is fixed to the slider 3, and the pressure receiving part thereof is the pressure transmitting part 2.
1 is connected to the sucker receiver 3-2. 2A and FIG. 2B, the holding arm 30 is not in contact with the sucker receiver 3-2 of the slider, so that no pressure is applied to the pressure sensor 20.

Next, in the state shown in FIG. 2C, the collar 2-1 of the sucker is brought into contact with the sucker receiving portion 3-2 of the slider, and the holding arm 3 is held.
In a state in which 0 is closed, the holding arm 30 returns the collar portion 2-1 of the sucker to the sucker receiving portion 3-2 of the slider and is pressed by the force of the spring 32. In this state, since the holding arm 30 presses the collar 2-1 of the sucker against the sucker receiving portion 3-2 with the force of the return spring 32, the pressure sensor 20 detects the return spring 32.
Output corresponding to the power of

FIG. 3 is a graph showing the relationship between the pressure applied to the pressure sensor 20 and the output thereof.
And points 2, 3, and 4 correspond to various operating states as the pressure increases. In the graph of the pressure sensor 20 shown in FIG.
As shown in B, no pressure is applied to the pressure sensor 20 when the syringe is not set on the slider, and thus the output is zero. The point on the vertical axis 3 is in the state shown in FIG. 2C since the collar 2-1 of the sucker abuts on the sucker receiver 3-2 of the slider and is pressed and held by the holding arm 30. The output is 20. In this state, the motor 7 does not operate and the slider 3 does not press the sucker 2.

Next, when the motor 7 of the driving mechanism shown in FIG. 1 is rotated in a predetermined direction at a predetermined speed in a state shown in FIG. 2C, the slider 3 engaged with the feed screw 5 is moved at a predetermined speed.
Is pressed in a predetermined direction and the liquid is delivered. The output of the pressure sensor 20 rises from a value of 3 corresponding to the normal pressure value required for the delivery of the liquid, and the maximum value of this pressure is set to 4 Set as a point. Further, for example, the position of point 2 is set between the position of point 3 and the position of point 1 in order to detect the negative pressure of the sucker. The points 1, 2, 3, and 4 of the pressure values shown in FIG.
Compared with the output of 0, the processing signal corresponding to each state is output.

1. When the output of the pressure sensor 20 reaches the value of the point 1, a signal indicating that the syringe has not been set is output to 2. When the output of the pressure sensor 20 exceeds the value of the point 3 and is equal to or less than the value of the point 4, a signal that is determined to be in normal operation is given as “3. If the output of the pressure sensor 20 exceeds the value of the point 4, a signal that is determined to be in an overload state is output. Pressure sensor 2
When the output of 0 becomes smaller than the value of the point 2, the respective signals are transmitted to determine that a negative pressure has acted on the sucker.

[0014]

Since the infusion device according to the present invention has the above-described configuration, the output of the pressure sensor is compared with the value set in the comparison circuit to determine whether an overload condition, a syringe disconnection condition, or the like has occurred.
Since each of the negative pressure generation states can be detected and a signal can be output, there is an effect that a safe infusion operation can be performed.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing the overall configuration of an infusion device according to the present invention.

FIG. 2A is a cross-sectional view of a main part of a slider portion of the infusion device according to the present invention.

FIG. 2B is a sectional view of a main part of a slider portion of the infusion device according to the present invention.

FIG. 2C is a sectional view of a main part of a slider part of the infusion device according to the present invention.

FIG. 3 is a characteristic diagram of a pressure sensor of the infusion device according to the present invention.

FIG. 4 is a drawing of a main part of a mounting part of a pressure sensor of a slider of a conventional infusion device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Syringe 2 Suction piece 2-1 Suction piece flange 3 Slider 3-2 Suction piece end receiving part 4 Carriage 5 Feed screw 6 Gear 7 Drive motor 8 Slit plate 9 Photocoupler 11 Comparison circuit 12 Motor drive circuit 13 CPU 14 Encoder processing circuit 20 Pressure sensor 21 Pressure transmission unit 30 Holding arm of flange 31 Support shaft of arm 32 Return spring of support shaft

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Daio Miura 10 Oji Shinshinjin, Chiyoda-cho, Yamagata-gun, Hiroshima Prefecture Inside the JMS Chiyoda Plant

Claims (2)

[Claims] An infusion device having a feed screw driven by a prime mover and configured to press a sucker of a syringe by a linearly movable slider engaged with the feed screw to send out liquid, wherein a flange of the sucker is provided. The slider has a holding arm for pressing and holding the sucker in a direction opposite to a direction in which the sucker is pressed, and a pressure sensor is provided in the sucker receiving portion of the slider, and the holding arm A processing circuit for holding the collar portion of the sucker at the sucker receiving portion of the slider, and comparing the output value of the pressure sensor with a plurality of separately set reference values to generate a processing signal. Infusion device characterized by the above-mentioned. 2. A plurality of reference values set in a processing circuit for comparison with an output of a pressure sensor are sequentially set to 1, 2, 3, and 4 in order of a value larger than a smaller value, and a slider sucker receiver is set. The output value of the pressure sensor when the collar portion of the sucker is not held in the portion is set to 1, and is larger than the output value 1, and the pressure when the collar portion of the sucker is held in the slider receiving portion of the slider. The output value of the sensor is set to 3, the output value of the pressure sensor when the maximum value of the delivery pressure is larger than the output value of 3 is set to 4, and the output value between the output value 3 and the output value 1 is set to 2 , 1. When the output of the pressure sensor becomes the reference value of 1, a signal indicating that the syringe is not set is given as follows: 2. When the output of the pressure sensor exceeds the reference value of 3 and is equal to or less than the reference value of 4, a signal determined to be normal is obtained. 3. When the output of the pressure sensor exceeds the reference value of 4, a signal that is determined to be in an overload state, The infusion device according to claim 1, wherein a signal is transmitted when it is determined that the output of the pressure sensor has reached a value of 2.