FR2645025A1 - Electronic flow rate regulator for infusions (drips) and transfusions - Google Patents

Abstract

Electronic device for regulating any systems with flow of a liquid from any container through a tube (infusion, drip, transfusion, etc.). The invention relates to an electronic device making it possible accurately to regulate, from a drop counter fitted with an alarm, a passage of liquid through a tube. This electronic device consists of a casing 7 containing an electronic module, itself composed of a servocontrol 3, a control circuit 5 and a regulator 6, comprising a notch 8 fitted with a block 2 receiving the tube 4 squashed by a cam 1. The device according to the invention is in particular intended for medical use (infusions, drips, transfusions).

Description

 The present invention relates to a device for precisely regulating the flow rate of an infusion or a trsnefusion.

 The flow of a liquid, whatever it is, contained in glass bottles, in flexible bags or other containers is traditionally conveyed to its recipient by a pipe equipped with a dropper cage and a flow regulator mechanical.

This regulator commonly called "roulette" or "disc" does not assure a good reliability of the system because the irregularity of the flow can go up to more or less 50% and parrois it is impossible to regulate this flow.

 The device according to the invention overcomes these drawbacks.

The studied system works with two complementary equipment:
- a programmable counting system which detects the passage of the drops and which is fixed to the rigid part of the perfusion device. This infrared diode system counts the drops very precisely thanks to a quartz time base. A value of drops per minute can be selected and an alarm is triggered if more or less 10% is exceeded.

 - a slave control system is mounted downstream at any point on the supply nozzle. This system is positioned on ignition in the closed position and exerts a strong pressure on the tubing thus preventing any passage of liquid.

The flow control is then actuated until the desired congress of drops per minute is obtained by means of the slave control system described above.

 At the desired value, the alarm system is then activated and the servo-control is controlled by the overruns of programmed value, in a range that is at least 10%.

 The accompanying drawings illustrate the invention in FIG. 1 shown, seen from above, the device according to the invention.

rigure 2 represents the operating principle diagram
Figure 3 shows a close-up of the cam.

Figure 4 shows the positioning of its carafe relative to the case.

Figure 5 shows the block diagram of operation.

Figure 6 shows an overview of the device.

 With reference to these drawings, the device comprises a housing (7), one of the side faces of which is provided with a notch (8) allowing the passage of the tubing (4) which is positioned in the bottom of this notch (8), on the crushing shoe, (2) which performs a role of vice via the cam (1).

 The box (7) also includes WL Jervocotmande electronic (3) connected to a control circuit (5) with adjustment (6).

 This assembly receives the control pulses from the drop detector (9) equipped with an alarm (10).

 The active part u used is a servo control (3) equipped with a movable cam (1) whose angle variations are modified by the variation of a square signal which serves as a reference.

 A voltage controlled variable frequency square wave generator is used to control angle variations.

 A voltage variation controlled by a potentiometer varies the frequency at the terminals of the servo control (3), in a positive or negative direction. to the right or to the left).

 This angle variation generates a pressure variation on the tubing (4), causing a proportional variation in the flow in a positive or negative direction.

 The alarm information from the drop counter (IO) is used to control the control circuit (5).

 Indeed, a control voltage is emitted in the direction of the servo-control (3), if the positive number of drops programmed is exceeded. The same applies in the event of a negative value being exceeded.

 These voltages are taken into account by the generator of square signals that will vary its frequency as a function of the aforementioned signals.

 This variation in frequency results in a variation in the angle of the servo-control (3) which directly influences the cam (1) and consequently on the drop rate, When the alarm control voltage (10) disappears, the servo-control (3 ) returns to its original position via the cam (1).

 We have deduced from the above that an alarm (10) exceeding 10% of the programmed number of drops sends. a control servo control lension (3) which compresses the supply manifold; ion (4).

thanks to camme (1). The flow is then slowed down and the alarm (10) ceases as does the control voltage. The cam (1), then resumes its original position.

 The same is true during a flow reduction resulting in a negative alarm (tO). The servo control (3) has a reverse sirex and the cam (i) moves away from the tubing (4) thereby increasing the flow of drops until the alarm (10) stops.

 The device according to the invention must allow all flow regulations concerning the flow of a liquid coming from any container and circulating through a flexible pipe.

Claims (5)

 t) Electronic system to regulate precisely all the flows of liquid coming from any container by means of a tube. The regulation of the flow takes place by the controlled crushing of the tubing (4) against a shoe (2) by a cam (i) thanks to a control with adjustment t6).  2) Device according to claim 1 characterized in that the housing (7) comprising: servo-control (3), control circuit (5) and adjustment (6), has a notch (8)  3) Device according to revenaieasion 1 and. 2 characterized in that the 4 notch (8) receives at its bottom and over its entire length a crush shoe (2).  4) Device according to claim t characterized in that a cam (1) crushes the tube (4) against the shoe (2).  5) Device according to claim 1 characterized in that the adjustment account (6) allows the enoix of the desired flow before taking charge by the electronics.