JP2898802B2 - Air mat - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air mat. More specifically, the present invention relates to an air mat that prevents bed sores seen in chronic bed patients and provides comfortable sleeping comfort for healthy persons.

[0002]

2. Description of the Related Art As an air mat of this type, a number of elongated air cells are arranged adjacent to each other and divided into two groups, for example, two groups of odd-numbered cells and even-numbered cells from one end. There is known a structure in which a cell is expanded and contracted by alternately supplying and exhausting air through a thin air pipe (for example, Japanese Utility Model Laid-Open No. 3-41431).

[0003]

In the air mat disclosed in the above-mentioned publication, supply and exhaust are alternately repeated between two types of air cells to prevent bedsores caused by pressure applied locally to a human body for a long time. At the same time, it refers to the relationship between the air pressure during supply and the air pressure during exhaust. That is, by setting the pressure after exhaust to about 70 to 90% of the pressure after supply, prevention of discomfort and maintenance of good blood circulation are achieved. However, the subsequent studies by the present inventors have found that making the above-described relationship between the air pressure of the exhaust cell and the air pressure of the air supply cell does not always provide satisfactory results in terms of comfort and blood circulation.

[0004] The present invention has been made to solve the above-mentioned problems, and by examining and further developing the technology disclosed in the above-mentioned gazette, an optimum condition satisfying both good sleeping comfort and maintenance of blood circulation has been established. It is intended to provide a realized air mat.

[0005]

According to the present invention, there is provided a first air cell group comprising a plurality of elongated flexible hollow air cells, and a first air cell group comprising a plurality of elongated flexible hollow air cells arranged alternately. A second air cell group consisting of
An air pump for supplying air to the first and second air cells, respectively, and an air pump interposed between the air pump and the first and second air cells for alternately switching between air supply and exhaust to the first and second air cells. And a control unit for controlling the air pressure after the exhaust of the first or second air cell group from 1/3 to 2/3 of the air pressure after the air supply.
Is set in the range of.

Each of the air cells of the first and second air cell groups is formed in a substantially frustoconical shape, and the large diameter portions of each of the air cells of the first air cell group are arranged in the same direction. It is preferable that the large diameter part of each air cell of the air cell group is arranged at a position opposite to the large diameter part of each air cell of the first air cell group.

[0007] Further, in order to prevent bedsore of a chronic bed patient who has difficulty moving his body, the control unit is required to increase the pressure after the air supply of the first or second air cell group to 250 to 600 mmAq.
And set the pressure after exhaust to 1
It is preferable to set in the range of ３ to ２.

In addition, for a healthy person who can freely move his / her body, the control unit controls the pressure after exhaust of the first or second air cell group to be な い し to ／ of the pressure after supply.
It is preferable to set within the range.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An air mat according to the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a perspective view of an air switching valve in one embodiment of the air mat of the present invention, FIG. 2 is a sectional view taken along the line II of FIG. 1, FIG. 3 is a plan view of a rotor in FIG. 1 is a plan view of a fixed plate, FIG. 5 is a circuit diagram of an air switching valve according to an embodiment of the present invention, FIG. 6 is a curve diagram showing human body pressure and its tissue permissive characteristics, and FIG. FIG. 8 is a plan view for explaining the operation of the switching valve, FIG. 8 is a waveform diagram for explaining the operation of the air switching valve in FIG. 1, and FIG. 9 is a perspective view showing one embodiment of the air mat of the present invention.

FIG. 9 shows the overall structure of the air mat, and FIG.
Are air mats, 2a, 2a... Are a first air cell group composed of a plurality of elongated, substantially frustoconical, flexible hollow air cells, 2b, 2b
.. Are second air cell groups having substantially the same shape as the first air cell groups 2a, 2a,. As the material of the first and second air cell groups 2a, 2a, 2b, 2b, etc., a material in which polyvinyl chloride is laminated on both sides or one side of a woven fabric such as nylon can be used. 3a is the first air cell group 2a, 2b
Are the first air pipes used to supply and exhaust air to and from the second air cells 2b, 2b, and 4 are control units. The control unit 4 includes the first and second air pipes 3.
Air switching valve 6 for alternately switching air supply and exhaust to a and 3b
(See FIG. 1), a motor 7 for driving the air switching valve 6
1 (see FIG. 1), an air pump (not shown) for supplying air to the air switching valve 6, a control circuit for the motor 7, and the like are incorporated. 8 is a first and second air cell group 2a, 2a
Sheets that wrap ..., 2b, 2b ...

1 to 4, reference numeral 6 denotes an air switching valve, which comprises a fixed plate 9 and a disk-shaped rotor 10. Reference numeral 7 denotes a motor for driving the rotor 10 to rotate. The rotor 10 is fixed to a rotating shaft 11 of the motor 7. Reference numeral 12 denotes a coil spring having one end fixed to the rotating shaft 11, which presses the rotor 10 against the fixing plate 9 to bring them into close contact with each other. The rotor 10 has an air distribution groove 13 formed in a fan-shaped recess on the contact surface side of the fixed plate 9, an air supply groove 14 formed around the central axis in communication with the air distribution 13, and a center from the distribution groove 13. Exhaust hole 15 composed of a plurality of small holes at positions opposite to each other across the shaft
Having. 16 is a central hole through which the rotating shaft 11 of the motor 7 passes,
Reference numeral 17 denotes a pair of switch control protrusions formed on the side surface of the rotor 10 so as to face each other. The fixing plate 9 has one air introduction hole 18 opened on the surface where the rotor 10 contacts, and two first and second air discharge holes 19 and 20. The introduction hole 18 is connected to an air pump, and the first discharge hole 19 is connected to the first air cell group 2a, 2a,... Via the first air pipe 3a.
20 is a second air cell group 2b, 2b ... via a second air pipe 3b.
Is communicated to. 25 is an introduction pipe communicating with the introduction hole 18, 26, 27
Are the first communicating with the first and second discharge holes 19 and 20, respectively.
And a second discharge pipe. Reference numeral 21 denotes a hole formed at the center of the fixing plate 9, which is penetrated by the rotating shaft 11 of the motor 7. The fixed plate 9 is separated from the fixed shaft 11 and does not rotate.
Reference numeral 22 denotes a limit switch disposed adjacent to the rotor 10, and includes a roller lever type actuator 23.
The roller 24 at the tip of the actuator 23 is in contact with the side surface of the rotor 10, and detects the portion where the protrusion 17 exists and the portion where it does not exist, and outputs an on / off signal. In the case of the present embodiment, the state where the roller 24 is located on the projection 17 is on, and the other states are off.

FIG. 5 shows a control circuit in the control section. In the figure, reference numeral 28 denotes a microcomputer (hereinafter referred to as a microcomputer) which receives a detection signal from the limit switch 22 and outputs a drive control signal for the motor 7. An on / off circuit 29 receives the control signal and outputs an on or off drive signal to the motor 7. Reference numeral 30 denotes a key switch, which is provided with keys for three types of operation instructions, for example, "early eyes", "normal", and "late eyes". The operation signal is input to the microcomputer 28, and the supply and exhaust periods of the first and second air cell groups 2a, 2a,..., 2b, 2b. First and second air cell groups 2a, 2a ..., 2b, 2b
.. Are alternately supplied and exhausted at intervals of about 4 to 22 minutes by driving the air switching valve 6. First and second air cell groups 2a, 2a
, 2b, 2b ... are elongated frusto-conical shapes, so that the compression area on the occupant changes from right to left and from left to right, and a light rolling exercise is applied to the occupant. Microcomputer
With 28, a "1 / f fluctuation" characteristic (f is a frequency) is given to this cycle, and a rolling motion having "1 / f fluctuation" can be added to the occupant. “1 / f fluctuation” means that in a time series signal, the relationship between the frequency f constituting the signal and the energy E belonging thereto is

[0014]

(Equation 1)

Means a state where Various repetitive signals and signal transmission characteristics in the human body have a “1 / f fluctuation” characteristic, so that external stimulation is considered to be comfortable. For example, heartbeat fluctuations and music are sound pressure stimuli that give pleasure to people, and the fluctuations in the sound power have a 1 / f spectrum. Human beings are given "1
/ F fluctuation "tends to be felt as pleasure. For example, in this embodiment, the supply and exhaust cycles are 4 to 10 minutes for the "early eye", 6 to 15 minutes for the "normal", 10 to 22 minutes for the "late eye", and "1 / f fluctuation". It is a combination.

The first and second air cell groups 2a, 2a ..., 2b,
The air pressure inside the cell after the exhaust of 2b ...
It is set in the range of 3 to 2/3. This is because a large number of clinical experiments have confirmed that when the air pressure after air supply and exhaust is set to this relationship, the unevenness formed in the air supply and exhaust cell group does not cause discomfort to the body and gives an extremely comfortable feeling. The most desirable ratio was about 1/2. The pressure after exhaust is 1 /
If it is lower than 3, an uncomfortable feeling of protrusion and even tenderness may be felt. On the other hand, if it is raised more than 2/3, there is no step and uniform pressure is continuously applied to the body. As a result, there is no improvement in the blood circulation maintaining effect, and in the case of a healthy person, the patient must frequently turn over.
Also, in the case of a truncated conical air cell, substantially no rolling movement can be obtained.

FIG. 6 shows the tissue tolerance curve of the human body according to the body pressure and its duration. The body pressure is a local body pressure, and it can be seen that if the state is maintained without moving, the tissue cannot endure in a region above the solid line, causing bedsore. For example, in a general hospital bed, the body pressure may locally reach 2000 mmAq, so it is necessary to change the body position such as turning over within two hours. As can be seen from FIG. 6, the body pressure is generally about 400 m for a healthy person.
It is said that capillary occlusion does not occur below mAq. In a healthy person, even if the body pressure is high in the area that supports the body, bedsores will not occur if the pressure drops below 400 mmAq before the tissue is destroyed. This minimum value was further reduced in the weak and severely ill, and was empirically confirmed to be about 250 to 300 mmAq.

In the case of a patient who cannot move,
It is desirable that the pressure after the supply be set in the range of 250 to 600 mmAq and the pressure after the exhaust be set in the range of 1/3 to 1/2 of the pressure after the supply, that is, in the range of 80 to 300 mmAq. The reason for setting the post-exhaust air pressure to be equal to or less than １ ／ of the post-air supply air pressure is to increase the level difference between the air supply air cell and the exhaust air cell to promote blood circulation in the exhaust air cell portion. The upper limit of the post-evacuation air pressure is set to 300 mmAq, because if it exceeds this, the possibility of bedsores increases. Also, if set below 80 mmAq, the strength to support the patient's body will be weakened, the cell will be crushed by the weight,
There is a fear that the body may come into contact with the floor surface (called bottoming), which is not preferable. When the air pressure after air supply is set in the range of 250 to 600 mmAq as described above, the air pressure relationship after air supply and exhaust can be in the range of 1/3 to 1/2, and the patient can comfortably sleep while promoting blood circulation. Can be given.

In the case of a healthy person who can freely move his / her body while sleeping, it is possible to freely adjust such as hardening or softening according to the user's weight, age, preference, and the like. In this case, in order to suppress the feeling of excessive unevenness and make the sleeping comfortably comfortable, the pressure after exhaust is set to 1/2 to 2 / of the pressure after supply.
It is desirable to set in the range of 3. The reason why the post-exhaust air pressure is set to be equal to or more than の of the post-air supply air pressure is to minimize a step generated between the air supply and exhaust air cells. For healthy subjects, improvement of sleeping comfort is given priority over prevention of blood circulation inhibition. Here, the pressure after air supply is desirably in the range of 300 to 800 mmAq, and the pressure after exhaust is 1/2 to 2 times the pressure after air supply.
It is set in the range of about 150 to 540 mmAq so as to satisfy the relationship of / 3. 300 to 800m as air pressure range after air supply
mAq is suitable because if the pressure is raised beyond this range, the air cell becomes too stiff, causing inconvenience such as a feeling of protrusion and even pain. In addition, if the pressure is lower than this range, the step generated between the exhaust air cell and the exhaust air cell becomes small, which is not optimal, and the air cell is crushed by the weight and the comfortable hardness cannot be obtained. Was also confirmed by clinical experiments.

Next, referring to FIGS. 7 and 8, the driving of the air switching valve 6, the supply / exhaust state of the air cell, the limit switch 22
The relationship between the on / off operation of the motor 7 and the on / off operation of the motor 7 will be described. 7 and 8 show a case where the air mat is used as a bedsore prevention air mat. In FIG. 8A, a waveform A indicates the air pressure of the first air cell group 2a, 2a,.
Waveform B indicates the atmospheric pressure of the second air cell group 2b.
The air pressure after air supply is about 500 mmAq, and the air pressure after exhaust air is about 250 mmAq. This value is variably adjusted depending on the pressure regulating valve of the air pump, the exhaust time, and the area of the exhaust hole.

FIG. 7A shows a state immediately after the distribution groove 13 is located on the first discharge hole 19 and the limit switch 22 is switched from on to off. When the limit switch 22 is turned off, a motor-off signal is output from the microcomputer 28, and the rotation of the rotor 10 stops. Suspension period T1 starting from this point
Is arbitrarily set in a predetermined period, for example, in a range of about 4 to 22 minutes by the built-in clock of the microcomputer 28. The period T1 is changed every cycle, and is programmed so as to generate “1 / f fluctuation”. During this period, the air from the air pump is supplied to the first air cell group 2a via the air introduction hole 18, the first discharge hole 19, the first discharge pipe 26, and the first air pipe 3a. The first air cell group 2a is maintained at about 500 mmAq. At this point, the second air cell group 2a, 2a,... Has been evacuated and sealed while maintaining about 250 mmAq.

FIG. 7 (b) shows the state of the microcomputer 28 after the elapse of the period T1.
, A motor-on signal is output via an on / off circuit 29, and the rotor 10 starts rotating in the direction of arrow X in the figure. As a result, the distribution groove 13 becomes the first discharge hole 19
From the top to the second discharge hole 20 and the first air cell group 2
The air supply to the air cells a, 2a,... is stopped, and the air supply to the second air cell group 2b, 2b,. The drive period T2 of the motor 7 is determined by the microcomputer 28 when the limit switch 22 is turned on.

FIG. 7 (c) shows the state of the microcomputer 28 after the elapse of the period T2.
This indicates a state where the motor-off signal is output and the rotor 10 stops. The suspension period T3 is set to about one minute.
Air is supplied to the second air cell group 2b during the period T2 and the period T3. After the elapse of the period T3, the microcomputer 28 outputs a motor-on signal, and the motor 7 rotates.

FIG. 7D shows a drive period T4 of the motor 7 (about 6
Seconds), the motor-off signal is output and the motor 7
Indicates a stopped state. During this period T4, the rotor 10
Is set so as to coincide with the time when the exhaust holes 15 are located on the first exhaust holes 19. At this position, the rotor 10 is in the period T5 (about 4
Seconds). During this period T5, the first air cell group 2a,
The exhaust time of 2a ... is adjusted as the time until the residual pressure in the cell decreases to about 250 mmAq. After the elapse of the period T5, the motor 7 starts rotating according to the motor-on signal from the microcomputer 28, and continues to rotate during the period T6.

FIG. 7 (e) shows a state in which the limit switch 22 has passed the projection 17 due to the rotation of the rotor 10, and has been switched from ON to OFF. In response to the off signal, the microcomputer 28 outputs a motor off signal, and the motor 7 stops. From this point, the motor 7 keeps stopping for a period set by the microcomputer 28, that is, a period T7 selected from the range of about 4 to 22 minutes. This period T7 is the same as the aforementioned period T1
Is set by the microcomputer 28 as a period during which "1 / f fluctuation" having the same property as that described above occurs. During this time, the first air cell group 2a, 2a ... is maintained in an exhaust state (residual pressure of about 250 mmAq), and the second air cell group 2b, 2b ... is maintained in an air supply state (about 500 mmAq). After the elapse of the period T7, the microcomputer 28
When the ON signal is output, the motor 7 starts rotating, and continues to rotate during a period T8 until the limit switch 22 is turned on.

FIG. 7F shows the distribution groove 13 immediately after the rotation of the motor.
Indicate a state where air supply to the first air cell group 2a, 2a,... Has been started.

FIG. 7 (g) shows a state where the limit switch 22 rides on the protrusion 17 and is switched on at the end of the period T8. After the elapse of the period T8, the microcomputer 28
Outputs a motor-off signal, and the motor 7 stops. During the period T9 following this, the motor 7 stops. Period T8
And the first air cell group 2a over substantially the entire period of the period T9,
Air is supplied to 2a…, and the pressure inside the cell becomes about 500mmAq.
The stop period T9 of the motor 7 is set to a time (approximately 1 minute in this embodiment) sufficient for the atmospheric pressure to reach approximately 500 mmAq.
Is set by After the elapse of the period T9, the motor 7 starts rotating.

FIG. 7 (h) shows an exhaust hole due to the rotation of the rotor 10.
15 moves onto the second discharge hole 20, and the second air cell group 2b, 2b.
3 shows a state in which the exhaust is started. When the period T10 has elapsed, the exhaust hole 15 coincides with the second exhaust hole 20, and
In this position, the motor 7 stops for the next period T11 (about 4 seconds). During the stop period T11, the evacuation of the second air cell group 2b, 2b,... Is continued, and the air pressure drops to about 250 mmAq. After the elapse of the period T11, a motor-on signal is output from the microcomputer 28, and the motor 7 is driven to rotate.
The exhaust hole 15 passes over the second exhaust hole 20 and the exhaust operation ends. In this state, the first air cell group 2a, 2a... Is maintained at a high pressure of about 500 mmAq, and the second air cell group 2b,
2b ... is maintained at a low pressure of about 250 mmAq. The limit switch 22 is projected by the rotation of the motor 7 and the rotor 10.
After passing through 17, the limit switch 22 turns off and the motor 7 stops. Thus, one cycle of the air supply and exhaust operations of the first and second air cell groups 2a, 2a,..., 2b, 2b. Thereafter, a similar cycle in which only the periods T1 and T2 are changed is repeated.

Although the above description based on FIGS. 7 and 8 has been directed to an air mat for preventing bedsores, the present air mat can also be used as an air mat for a healthy person. In this case, the air pressure after air supply can be adjusted by adjusting a pressure regulating valve provided in the air pump, and the air pressure after exhaust air can be adjusted by adjusting the period T5, or by adjusting the number of small holes of the exhaust holes 15. it can.

[0030]

According to the present invention, since the air pressure of the exhaust air cell group is set in the range of 1/3 to 2/3 of the air pressure of the air supply air cell group, the most comfortable sleeping comfort for the sleeping person is obtained. Can be provided.

According to the present invention, each of the air cells of the first and second air cell groups has a substantially frusto-conical shape.
A moderate rolling exercise, that is, a light turning action, can be given to the sleeping person, and blood circulation can be promoted.

Further, according to the present invention, when the air mat is used for a chronic bed patient, the pressure after exhaust is set within a range that does not cause blood circulation obstruction, so that it is possible to prevent bedsore.

[Brief description of the drawings]

FIG. 1 is a perspective view of an air switching valve in one embodiment of an air mat of the present invention.

FIG. 2 is a sectional view taken along line II of FIG. 1;

FIG. 3 is a plan view of the rotor in FIG. 1;

FIG. 4 is a plan view of a fixing plate in FIG. 1;

FIG. 5 is a circuit diagram of an embodiment of an air switching valve according to the present invention.

FIG. 6 is a curve diagram showing a human body pressure and its tissue tolerance.

FIG. 7 is a plan view for explaining the operation of the air switching valve of FIG. 1;

FIG. 8 is a waveform diagram for explaining the operation of the air switching valve of FIG. 1;

FIG. 9 is a perspective view showing an embodiment of the air mat of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Air mat 2a 1st air cell group 2b 2nd air cell group 4 Control part 6 Air switching valve 7 Motor 9 Fixed plate 10 Rotor 13 Distribution groove 14 Air supply groove 15 Exhaust hole 17 Projection 18 Air introduction hole 19 First discharge hole 20 First 2 discharge hole 22 limit switch 28 microcomputer 29 on / off circuit 30 key switch

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-186214 (JP, A) JP-A-4-348714 (JP, A) JP-A-3-56433 (JP, U) JP-A-3-348 88067 (JP, U) Japanese Utility Model Application Hei 3-85955 (JP, U) Japanese Utility Model Application Hei 2-84626 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) A47C 27/00-27 / 22 A61G 7/05

Claims (4)

(57) [Claims] 1. A first air cell group comprising a plurality of elongated flexible hollow air cells, and a second air cell group comprising a plurality of elongated flexible hollow air cells, the second air cell group being arranged alternately with the first air cell group. An air pump for supplying air to each of the first and second air cells, and a first air pump interposed between the air pump and the first and second air cells;
And a control unit for alternately switching between air supply and exhaust to the second air cell group, wherein the control unit sets the post-exhaust air pressure of the first or second air cell group to the post-air supply air pressure. An air mat set in a range of 1/3 to 2/3. 2. The air cells of the first and second air cell groups are formed in a substantially frusto-conical shape, and the large diameter portions of the air cells of the first air cell group are arranged in the same direction. 2. The air mat according to claim 1, wherein the large diameter portion of each air cell of the air cell group is arranged at a position opposite to the large diameter portion of each air cell of the first air cell group. 3. An air mat for preventing bedsores of a chronic bed patient who is incapable of moving his body, wherein the control unit controls the air pressure after air supply of the first or second air cell group to 250.
3. The air mat according to claim 1, wherein the air mat is set in a range of 1 to 600 mmAq, and the pressure after exhaust is set in a range of 1/3 to 1/2 of the pressure after supply. 4. An air mat for a healthy person who can freely move his / her body, wherein the control unit sets the post-evacuation pressure of the first or second air cell group to の of the post-supply pressure.
The air mat according to claim 1, wherein the air mat is set within a range of 2/3.