JPS6153057B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a blood pressure measuring device, and in particular to a technique for efficiently measuring blood pressure by quickly applying compression with a cuff after wrapping the cuff around a part of a living body. It is related to.

Prior Art A bag-shaped flexible band is formed along the inner surface of a flexible band by using the driving force of an air cylinder to pull the other end of a flexible band that is fixed at one end and has a substantially cylindrical shape. A blood pressure measuring device is known that includes a cuff device that reduces the diameter of a cuff and wraps it around a part of the human body. For example, UK Patent No. 852464
This is the device described in No. In such conventional devices, prior to blood pressure measurement, air is forced into the air cylinder and actuated to wrap the cuff around the part of the human body, and then air is forced into the cuff. It is common to press a part of it.

Problems to be Solved by the Invention However, according to such conventional blood pressure measuring devices, when increasing the pressure of the cuff after activating the air cylinder, the pressure is increased from atmospheric pressure. Because it takes a long time to raise the blood pressure to a certain level, blood pressure measurements are not always carried out efficiently.

Means for Solving the Problems The present invention has been made against the background of the above-mentioned circumstances, and its gist is, as mentioned above, that air is forced into an air cylinder prior to blood pressure measurement. In a blood pressure measuring device in which a cuff is wrapped around a part of the human body by operating the air cylinder, and then air is forced into the cuff to compress the part, the air in the air cylinder when the cuff is wrapped is A communication path is provided that connects the inner chamber on the side where the air is pumped and the cuff, and the communication path is opened and closed when air is forced to be fed to the cuff after the cuff has been wrapped by the air cylinder. This is due to the provision of a valve.

Operation and Effects of the Invention With this structure, the on-off valve is opened when air is forced to be fed to the cuff after the air cylinder is operated, so that the cuff is connected to the air cylinder via the communication path. Pressurized air can be rapidly supplied from the inner chamber. Therefore, starting from the pressure obtained all at once by supplying the pressurized air, the cuff pressure is thereafter increased at a rate corresponding to the capacity of the air pump, so that the cuff can be quickly raised to the target pressure. Therefore, the time it takes for the cuff to rise to the target pressure is significantly shorter than in the past, and measurement can be started quickly, making blood pressure measurement more efficient.

Embodiment Hereinafter, an embodiment of the present invention will be described in detail based on the drawings.

FIG. 1 is an explanatory diagram schematically showing an example of the tightening part of the cuff device, and 1 is a flexible band made of a band-shaped metal plate, plastic sheet, etc. It is wound into a substantially cylindrical shape so that a part of the human body to be temporarily stopped can be inserted, and one end 1a thereof is fixed and housed in a cylindrical enclosing member (not shown), while the fixed end 1a is The other end 1b of the cylindrical enclosing member passes through a slot formed in the peripheral wall of the cylindrical enclosing member and can be pulled outward in the tangential direction (in the direction of the arrow) by an air cylinder 6, which will be described later. Furthermore, by attaching a cuff 2 of a predetermined width made of a rubber air bag along a part of the inner surface of the flexible band 1, a flexible air chamber is inserted into the flexible band 1. It is designed so that it can be formed between the human body part and the body part to be used. Furthermore, such cuff 2 includes:
A flow path 3, which is part of the pneumatic circuit, is attached so that air is forced into the cuff 2 through the flow path 3, and a microphone is provided to detect Korotkoff sounds in the arterial blood vessels. A sound detector 4 is attached.

FIG. 2 shows a pneumatic circuit for operating the cuff device, in which the other end 1b of the flexible band 1, which is not fixed, is fixed to the end of the piston rod 8a of the air cylinder 6 via the connecting member 5. The piston rod 8a is moved to the left (in the direction of the arrow) in the figure as the piston 8 is moved by the inflow of pressurized air into the operating side inner chamber 6a in the air cylinder 6. As a result, the flexible band 1 moves to the left, in other words, the wound band 1
It is designed so that it can be stretched in the tangential direction of the cylindrical shape and contracted in the circumferential direction around the inserted upper arm of the subject. Further, the piston rod 8a is provided with a clamper 9 operated by an electromagnetic solenoid, which can clamp the piston rod 8a that has been moved leftward to prevent its movement in the left-right direction. This ensures that the flexible band 1 does not return to its original state due to its own elasticity. In other words,
The clamper 9 is provided to prevent the flexible band 1 from moving rightward and returning to its tightening position relative to the upper arm.

The air cylinder 6 is provided with flow paths 10a and 10b, respectively, in order to guide pressurized air into the inner chambers on both the left and right sides of the piston 8, and are connected to a first solenoid valve (4-port solenoid valve) 11. ing. Further, the first solenoid valve 11 is connected to an air pump 12, which is a pneumatic pressure generator, via a flow path 14, and when the pump 12 is driven by a motor 13, pressurized air is supplied to the first solenoid valve. 11. In addition, the first solenoid valve 1
1 connects the flow path 14 and the flow path 10b to guide the pressurized air of the air pump 12 to the left inner chamber of the air cylinder 6 when the power is not energized, and opens the flow path 10a to the atmosphere, and vice versa when the power is energized. The flow path 14 and the flow path 10a are connected to guide the pressurized air of the air pump 12 into the right inner chamber 6a of the air cylinder 6, and the flow path 10b is opened to the atmosphere. A pressure setting device 15 is connected to the flow path 14 . This pressure setting device 15 includes a sensor that detects the pressure air of the air pump 12, a comparator that compares the pressure of the pressure air with a pressure indicated by a pressure setting signal supplied from a main body (not shown), and a pressure of the pressure air. and an output contact that closes when the pressure exceeds the pressure represented by the pressure setting signal.

Further, a flow path 16 that branches off a flow path 10a that guides pressurized air from the first solenoid valve 11 to the right inner chamber 6a of the air cylinder 6 for moving the piston rod 8a in the direction of the arrow is connected to a second solenoid valve (3). port solenoid valve) 17. Pressure air is supplied from the second electromagnetic valve 17 into the cuff 2 through a flow path 3, and is branched from the flow path 3 to direct the pressure air inside the cuff 2 into the atmosphere. Check valve 18 and throttle valve 19 for discharging to
An exhaust mechanism is provided. Therefore, in this embodiment, the flow path 10a, the flow path 16,
The flow path 3 constitutes a communication passage connecting the inner chamber 6a of the air cylinder 6 and the cuff 2, and the second electromagnetic valve 17 constitutes an on-off valve that is opened when air is force-fed to the cuff 2. be. In addition, the second solenoid valve 17
When the current is not energized, the flow path 16 is closed and the flow path 3 is opened to the atmosphere to rapidly exhaust the air inside the cuff 2, and when the current is energized, the flow path 16 and the flow path 3 are communicated and the cuff 2 is closed. It supplies pressurized air into the interior.

The pneumatic circuit configured as described above is automatically operated by a control circuit as shown in FIG. 3, for example.

Below, the right inner chamber 6 in the air cylinder 6 in FIG.
The operation will be explained with reference to the graph showing the air pressure in a and the time chart in FIG.

When the power switch (not shown) is turned on, the third
Power is supplied to the circuit shown. In this state, the clamper 9, the first solenoid valve 11, and the second solenoid valve 17 do not operate, but the motor 13 operates while the time limit contact (opens when time-up) of the timer TR1 is closed. Therefore, pressurized air is supplied to the left inner chamber of the air cylinder 6, the piston rod 8a is retracted, and the band 1 is brought into the most expanded state. The timer TR1 starts timing as soon as power is supplied, and opens its time-limit contact when a preset time-up time has elapsed, and the time-up time is the time required for the piston rod 8a to be retracted. After the piston rod 8a is reliably retracted, the time-limited contact is opened and the motor 1
Stop the operation of 3. Also, this timer TR1
The time-limited contact is always closed and the timer TR
After the time-up period of 1 has elapsed, the timer
Open only while power is supplied to TR1.
Therefore, when the time-limited contact is opened after the time-up period has elapsed, relay CR1 is activated and timer TR is activated.
1 remains open until the power supplied to it is cut off. Note that the relay CR1 provided in parallel with the time limit contact of the timer TR1 in FIG. 3 is not necessarily required.

Next, when the start switch 21 is pressed,
Relay CR1 operates and is self-maintained, and first electromagnetic valve 11 operates and motor 13 operates to rotate air pump 12. Therefore, as the pressure air supplied to the right inner chamber 6a of the air cylinder 6 rises, the piston rod 8a is pushed out in the direction of the arrow in FIG. The cuff 2 is wrapped around the human body part (upper arm) inserted into the body. Points A to C in FIGS. 4 and 5 show this state. Note that the rate of pressure increase increases after passing point B in Figure 4, but this is due to the difference between the human body part and the cuff 2.
This is because the gap between the piston rod 8a is eliminated, the piston rod 8a hardly moves, and the supplied pressurized air only contributes to the pressure increase.

When the pressure in the right inner chamber 6a of the air cylinder 6, that is, the pressure in the flow path 14, exceeds the pressure indicated by the pressure setting signal, the output contact of the pressure setting device 15 is closed, and the relay CR2 is activated. Fourth
Point C in the figure and FIG. 5 shows this state. For this reason, relay CR3 operates and its operation is self-maintained, and second electromagnetic valve 17 and clamper 9 are operated.

When the clamper 9 is actuated, the piston rod 8
a is clamped to prevent its movement. This completes the wrapping of the cuff 2 around the human body part, but the pressure of the pressurized air supplied to the right inner chamber 6a of the air cylinder 6 at this time is the pressure represented by the pressure setting signal, so the piston rod The driving force of the cuff 8a, that is, the wrapping force of the cuff 2, has a substantially constant magnitude determined by the pressure represented by the pressure setting signal. Therefore, prior to blood pressure measurement, the cuff 2 can be wrapped around the human body part with a constant and appropriate wrapping force regardless of the thickness of the body part, and over-wrapping or under-wrapping can be eliminated. There are advantages.

Furthermore, when the second solenoid valve 17 is operated, the inside of the cuff 2, which had been communicated with the atmosphere until then, is brought into communication with the flow path 16, and pressurized air from the flow path 16 starts to be supplied into the cuff 2. . At this time, the air pump 12 is continuously operating, but when the inside of the cuff 2 and the flow path 16 are brought into communication as described above, the pressurized air that has been stored in the inner chamber 6a is transferred to the flow path 16.
a, the air is rapidly flowed into the cuff 2 through the flow path 16, the second solenoid valve 17, and the flow path 3, so that the right inner chamber 6a of the air cylinder 6 due to the capacity of the cuff 2
The pressure in the cuff 2 decreases slightly to point F in FIG. 4, and the output contact of the pressure setting device 15 is opened again, but the pressure inside the cuff 2, indicated by the broken line in the figure, is raised all at once to point D. Note that the pressure inside the cuff 2 and the pressure in the right inner chamber 6a of the air cylinder 6 are the same pressure, so F
Point and point D are at the same position. Then, at the same time as the output contact of the pressure setting device 15 is opened, the relay
CR2 is deactivated, relay CR5 is activated, and its activation is self-maintained.

In this state, the content of the pressure setting signal supplied to the pressure setting device 15 is switched to a pressure value suitable for starting blood pressure measurement in response to the operation of the relay CR3 or the second electromagnetic valve 17. The pressure value is preset to a value that sufficiently exceeds the subject's systolic blood pressure value.

Then, when the pressure within the cuff 2 is increased toward the new pressure setting value and exceeds the pressure represented by the pressure setting signal, the output contact of the pressure setting device 15 is closed again, and the relay CR6 is activated. Its operation is self-maintained, and the operation of the motor 13 is stopped. A contact (not shown) of relay CR6 is used as a starting signal for a measurement circuit (not shown). That is, after the pressure within the cuff 2 is raised to a pressure suitable for starting blood pressure measurement, blood pressure measurement is immediately started. Point G in FIGS. 4 and 5 shows this state.

In this way, the cuff 2 is connected to the inner chamber 6a and the air pump 12 after the cuff 2 is brought into close contact with the human body part and the pressure in the inner chamber 6a of the air cylinder 6 is increased to a predetermined constant pressure. As the air pressure inside the cuff 2 increases at once,
Furthermore, since the air pump 12 fills up the air pressure that is insufficient, the pressure within the cuff 2 can quickly reach a pressure value suitable for starting blood pressure measurement, and blood pressure measurement can be carried out efficiently.

At point G, when the air pump 12 is stopped, the air in the cuff 2 is gradually exhausted through the fixed throttle valve 19 of the exhaust mechanism, the air pressure in the cuff 2 is gradually reduced, and the blood pressure is measured.
That is, the sound detector 4 normally attached to the cuff 2 detects the occurrence and disappearance of Korotkoff sounds occurring in the artery, and the air pressure value of the cuff 2 at that point is detected by the measurement circuit as the systolic blood pressure value and the diastolic blood pressure value. It is measured by Points G to H in FIGS. 4 and 5 show this blood pressure measurement state. Furthermore, even when the pressure of cuff 2 increases, the throttle valve 1
However, since the amount of pressurized air from the air pump 12 is much larger than the amount of air pumped out, it does not matter at all.

When blood pressure measurement is completed, output contact 2 of the measurement circuit
5 is closed, relay CR4 is activated, and at the same time, the self-holding of relays CR1, CR3, CR5, and CR6 is released. Therefore, the operation of the first solenoid valve 11 is released, the inner chamber 6a of the air cylinder 6 is opened to the atmosphere, and the left inner chamber is opened to the air pump 1.
2, the second solenoid valve 17 is deactivated, the inside of the cuff 2 is opened to the atmosphere, and the pressurized air inside the cuff 2 is rapidly exhausted.
The operation of the piston rod 8a is released and movement of the piston rod 8a is allowed, and the air pump 12 is further driven to rotate by the motor 13. Point H in FIGS. 4 and 5 indicates this state.

Therefore, as shown at points I and E in Figure 4,
The pressure inside the cuff 2 is immediately brought to atmospheric pressure, the subject's body part (upper arm) is relieved from pressure, and the pressure air supplied from the air pump 12 to the left inner chamber of the air cylinder 6 causes the piston to Rod 8a
is pulled in, the diameter of the flexible band 1 is expanded, and the restraint on a part of the human body is completely released. Incidentally, since power is supplied to the timer TR1 by releasing the self-holding state of the relay CR1, the time-limiting contact of the timer TR1 is activated when the time-up period elapses, in other words, the piston rod 8a is reliably activated. After being retracted, it is released and the operation of the motor 13 is stopped.

The above series of operations constitutes one control cycle, and the control cycle is repeatedly executed every time blood pressure is measured.

As described above, according to this embodiment, when air is force-fed to the cuff 2 after the cuff 2 is wrapped around the air cylinder 6 when measuring blood pressure,
Since the second electromagnetic valve 17 opens the communication path consisting of the flow paths 10a, 16, and 3, the pressurized air stored in the inner chamber 6a of the cylinder 6 is rapidly moved to the cuff 2,
The pressure in the cuff 2 is raised all at once to the value shown at point D in FIG. Starting from the pressure at point D, the pressure of the cuff 2 is then increased to point G at a speed corresponding to the capacity of the pump 12. That is, the target pressure can be quickly reached from atmospheric pressure. Therefore, the time it takes for the cuff 2 to reach the target pressure is significantly shorter than in the past, and the blood pressure measurement can be started earlier, allowing efficient blood pressure measurement.

Note that the present invention is not limited to these examples in any way, and various improvements and changes may be made based on the knowledge of those skilled in the art without departing from the spirit of the present invention.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram schematically showing an example of a tightening part of a cuff device, FIG. 2 is a diagram showing a device according to an embodiment of the present invention and its pneumatic circuit, and FIG. FIG. 4 is a diagram showing an example of an electric circuit used in the embodiment device shown in FIG. FIG. 5 is a time chart illustrating the operation of the electric circuit shown in FIG. 1: flexible band, 1a: one end, 1b: other end,
2: Cuff, 6: Air cylinder, 3, 10a, 1
6: Flow path (communication path), 6a: Inner chamber, 17: Second electromagnetic valve (on/off valve).

Claims (1)

[Claims] 1. A flexible band having a substantially cylindrical shape, one end of which is fixed, is pulled along the inner surface of the flexible band by using the driving force of an air cylinder. A cuff device is provided to reduce the diameter of a bag-shaped cuff provided and wrap it around a part of the human body, and prior to blood pressure measurement, the cuff is compressed by compressing air into the air cylinder and activating the air cylinder. In a blood pressure measuring device of the type that is wrapped around a part of the human body and then forced air is sent to the cuff to compress the part, an inner chamber in the air cylinder on the side where air is forced to be sent when the cuff is wrapped; A communication passage connecting the cuff with the cuff is provided, and an on-off valve is provided in the communication passage to be opened when air is force-fed to the cuff after the cuff has been wrapped by the air cylinder. blood pressure measuring device.