JPS60125782A - Driving device of gas driven pump - Google Patents

Abstract

PURPOSE:To permit to set a pressure nicely by a method wherein a dummy tank is provided at the outlet port of a driving pressure so as to be switchable to the gas driving type pump so that the dummy tank can receive positive and negative pressures in stead of the pump even in case the pump is intercepted. CONSTITUTION:When a cut-off valve 11 is closed and the cut-off valve 12 is opened to intercept a blood pump 5, the cut-off valve 13 is opened, the dummy tank 14 is connected to the coutlet port 10 of driving pressure and the dummy tank 14 receives the supply and suction of air from a positive pressure tank 3 and a negative pressure tank 4 instead of the blood pump 5. Pressures in both tanks 3, 4 are detected by pressure-electric converters 15, 16 and a difference between the detected pressure and a set pressure is obtained by an error comparator not shown in the diagram. Electric air flow amount control valves 8, 9 are conducted by an electric power amplifier, not shown in the diagram, in accordance with the error signal and the pressures in both tanks 3, 4 are regulated to set pressures. According to this method, the dummy tank 14 receives the regulated air pressures of the negative and positive pressure tanks 3, 4 instead of the blood pump 5 and good pressure setting may be effected.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a drive device for a gas-driven pump such as a blood pump.

This type of drive device includes, for example, a gas pressure source that supplies positive pressure (compressor, positive pressure tank), a gas pressure source that supplies positive pressure (vacuum pump, positive pressure tank), and a gas pressure source that supplies positive pressure and A solenoid valve is provided in the flow path between the driven pump (blood pump) and switches the gas pressure source (positive pressure tank, positive pressure tank), and the solenoid valve is switched at high speed to pump blood. Pumps are known in which positive pressure and positive pressure are applied alternately.

According to the above device, pressure regulating valves are provided between the compressor and the positive pressure tank and between the vacuum pump and the positive pressure tank, respectively.
The pressure regulating valve is used to regulate and set the pressure. Pressure setting may be performed while actually operating the blood pump, but if the blood pump cannot be operated, the pressure setting must be performed with the blood pump shut off. However, in this case, the amount of air flowing into the positive pressure tank is approximately equal to the amount of positive pressure air in the piping between the electromagnetic switching valve and the shutoff valve installed at the inlet of the blood pump's drive unit, and the pressure regulating valve is in a throttled state. , operation is unstable and control of positive pressure becomes extremely difficult. Additionally, the compressor and vacuum pump are almost at full capacity, resulting in overheating and overload.

The present invention has been made in view of the above circumstances, and its purpose is to provide a drive device for a gas-driven pump that allows for good pressure setting while the gas-driven pump (blood pump) is shut off. be.

That is, the present invention is characterized in that a dummy tank is provided at the drive pressure outlet so as to be switchable with a gas-driven pump.

Therefore, even if the gas-driven pump is shut off, the dummy tank can receive positive pressure instead of the gas-driven pump, and the pressure can be set satisfactorily.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an example of a drive device of the present invention. In the figure, 1 is a compressor, 2 is a vacuum pump, 2 is a positive pressure tank, 4 is a positive pressure tank, 5 is a sack type blood pump, 6,
7 is a solenoid valve, 8 and 9 are electropneumatic flow control valves, and 10 is a drive pressure outlet.

The blood pump 5 is connected to the drive pressure outlet 10 via a shutoff valve 11 and is shut off from the drive when the shutoff valve 11 is closed. When the cutoff valve 11 shuts off, the air in the drive section of the blood pump 5 (the space between the outer case and the blood chamber) is released to the atmosphere via the cutoff valve 12.

The electro-pneumatic flow control valve 8 is provided in a flow path connecting the inlets of the compressor 1 and the positive pressure tank 3, and is connected to the flow path from the compressor 1 to the positive pressure tank 3.
Pressure adjustment and pressure setting are performed by controlling the amount of air supplied to the

In addition, the electropneumatic flow control valve 9 is connected to the vacuum pump 2 and the positive pressure tank 4.
The vacuum pump 2 is provided in a flow path that continues through the outlet of the vacuum pump 2, and controls the amount of air sucked from the positive pressure tank 4 into the vacuum pump 2 to adjust and set the pressure.

A dummy tank 14, which is a feature of the present invention, is provided at the drive pressure outlet 10. This dummy tank 14 is
It is set to approximately the same capacity as the total capacity of the blood pump 5 and the piping leading to the blood pump 5, and is driven via a shutoff valve 13 that opens in conjunction with the shutoff valve 11 when the shutoff valve 11 closes and the shutoff valve 12 opens. It is connected to the pressure outlet 10 and can be switched with the blood pump 5. When the blood pump 5 is shut off, positive pressure and pressure are received from the positive pressure tank 3 and the positive pressure tank 4 instead of the blood pump 5.

Note that the positive pressure tank 3 and the positive pressure tank 4 are provided with piezoelectric converters 15 and 16 for detecting their internal pressures.

FIG. 2 shows a control device for the electropneumatic flow control valve 8 on the positive pressure side. This control device is composed of a setting signal generator 17, an error comparator 18, and a power amplifier 19.

The setting signal generator 17 generates a setting signal (
The setting signal can be changed in various ways according to external information, such as information from a living body (blood volume, blood pressure, etc.).

The 6-way difference comparator 18 is composed of a plurality of operational amplifiers 18a to 18c, and +r/li! of the operational amplifier 18a. A setting signal generator 17 is connected to the output terminal, and an operational amplifier 18
The piezoelectric transducer 15 described above is connected to one terminal of b. The setting signal of the setting signal generator 17 is the operational amplifier 18.
a, and the detection signal from the piezoelectric converter 15 (
Electricity (converted into M field) from the pressure inside the positive pressure tank 3 is amplified by the operational amplifier 18b. These signals are added (subtracted) by an operational amplifier 18c to obtain an error signal that is the difference between the setting signal and the detection signal.

The power amplifier 19 inputs this error signal and supplies a current to the electropneumatic flow control valve 8 according to the error signal. The electropneumatic flow rate control valve 8 changes the degree of opening of its port depending on this current value, and controls the amount of air as described above.

FIG. 3 shows a control device for the electropneumatic flow control valve 9 on the positive pressure side. This control device also includes a setting signal generator 20, an error comparator 21, and a power amplifier 22, similar to the one described above.

The setting signal from the setting signal generator 21 is amplified by an operational amplifier 21a, and the detection signal from the piezoelectric converter 16 (the pressure in the positive pressure tank 4 is converted into an electrical signal) is amplified by an operational amplifier 21b. These signals are operational amplifier 21c
and the error signal is obtained. Current is supplied from the power amplifier 22 to the electropneumatic flow control valve 9 in accordance with this error signal.

The electropneumatic flow rate control valve 9 changes the degree of opening of its boat depending on this current value, and controls the amount of air as described above.

Next, the operation of the above embodiment will be explained.

First, when the cutoff valve 11 is closed and the cutoff valve 12 is opened to cut off the blood pump 5, the cutoff valve 13 opens in conjunction with this.
A dummy tank 14 is connected to the drive pressure outlet 10. As a result, instead of the blood pump 5, the dummy tank 14 receives air supply and suction from the positive pressure tanks 3 and 4. At this time, approximately the same amount of air flows into the positive pressure tank 4 as when the blood pump 5 is operated. Then, predetermined pressures are set in the setting signal generators 17 and 20, respectively. The pressure in the positive pressure tanks 3 and 4 is determined by piezoelectric converters 15 and 16.
The difference between this detected pressure and the set pressure is determined by the error comparison 18.21, and according to this difference (error signal), the power amplifier 19.
is energized. As a result, from the compressor 1 to the positive pressure tank 3
The pressure in the positive pressure tanks 3 and 4 is adjusted to the set pressure six times by controlling the amount of pressurized air supplied to the vacuum pump 2 and the amount of air sucked from the positive pressure tank 4 to the vacuum pump 2.

After that, when the shut-off valve 13 is closed, the shut-off valve 11 is opened, the shut-off valve 12 is closed, the dummy tank 14 is switched to the blood pump 5, and the positive pressure and positive pressure are supplied from the positive pressure tank 3 and the positive pressure tank 4. Act alternately. During this operation, the pressures in the positive pressure tanks 3 and 4 are brought to a set pressure by the electropneumatic flow control valves 8 and 9.

In the above embodiment, the pressure is set and regulated using the electro-pneumatic flow control valves 8 and 9, but a mechanical pressure regulating valve may also be used. Moreover, although the case where the cutoff valves 11 and 12 and the cutoff valve 13 are linked is shown, the present invention is not limited to this, and they may operate independently.

Further, as shown by dotted lines in FIG. 1, primary pressure tanks may be provided on the positive pressure side and the positive pressure side, respectively.

Furthermore, although the case where the compressor 1 and the vacuum pump 2 are used is shown, either one may be used.

For example, when only the compressor 1 is used, the atmosphere becomes a positive pressure source, and when only the vacuum pump 2 is used, the atmosphere becomes a positive pressure source. Further, the blood pump is not limited to the Santa-type type, but can also be applied to diaphragm-type or other types, and can also be applied to drive artificial respirators, intra-aortic balloon pumps, etc. in addition to blood pump devices.

As explained above, according to the present invention, since the dummy tank is provided at the drive pressure outlet so as to be switchable with the gas-driven pump,
Even if the blood pump is shut off and the pressure is set, there are no problems such as difficulty in controlling the positive pressure or overheating or overloading of the compressor and vacuum pump that make up the gas pressure source.

[Brief Description of the Drawings] The drawings show one embodiment of the present invention, and FIG. 1 is an overall block diagram, and FIGS. 2 and 3 are a control device for the pressure regulating means (electro-pneumatic flow control valve). FIG. 5... Gas-driven pump 8.9... Pressure regulating means (electro-pneumatic flow control valve) 11-13.
...Shutoff valve 14...Dummy tank patent applicant Zeon Corporation

Claims (1)

[Claims] It is equipped with a positive pressure and/or a gas pressure source that supplies positive pressure and a pressure regulating means, and applies positive pressure or positive pressure intermittently to a gas-driven pump, or alternately applies positive pressure and positive pressure. 1. A driving device for a gas-driven pump, characterized in that a dummy tank is provided at a drive pressure outlet so as to be switchable with the gas-driven pump.