JP2001258957A - Bed monitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bed monitor with which the position of a patient on the bed can be accurately monitored while he is not aware that he is monitored for preventing him from falling from the bed. SOLUTION: This bed monitor is provided with a plurality of load sensors 21 which are placed under, in the inside of or on the surface of a mattress 11 laid on a bed 10 with a specified distribution and output load signals correspondingly to the applied load, a load signal processing circuit 31 capturing the plurality of load signals in sequence, a feature amount calculating means for calculating a feature amount of load distribution from the captured plurality of load signals, a posture and position calculating means for calculating the posture and the position of a person on the bed 10 from the feature amount of load distribution, and a signal generating means 40 for judging a predetermined specified posture and position among the calculated postures and positions of the person and generating report signals. The specified posture and position are the case of the person on the bed 10 with his upper part of the body raised up or the case in which the person is positioned on the right or left edge of the bed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bed monitor for preventing a patient from falling off a bed after operation, for example.

[0002]

2. Description of the Related Art In a cerebrovascular disorder patient or a postoperative patient, the body cannot move as desired, contrary to the will of the patient.
Accidents have also occurred in which the person fell off the bed in time to get up.

In order to prevent this, according to the 12th Rehabilitation Engineering Conference Lecture Book Volume 12, the following reports have been made. That is, a diffuse reflection type photoelectric sensor is installed on a bed-side top plate or a fixed stand of a support standing on a board, and when a patient gets up in the sensing area of the sensor, the sensor senses and a nurse call is activated.

[0004]

However, in the above-mentioned apparatus, the sensor also senses body movements other than the patient's rising motion (movements of the patient's arms or the like, or movements of the body of a nurse or the like). It is indistinguishable whether the call is based on the original patient's rising motion or the patient's own call.

Further, there is a problem that the patient understands the mechanism of the sensor and, for example, hangs a cloth on the sensor in order to avoid the above-mentioned inconvenience, thereby killing the function of the sensor. It was not enough.

In view of the above problems, it is an object of the present invention to accurately grasp the posture of a patient on a bed without being noticed by the patient,
An object of the present invention is to provide a bed monitor device that prevents falling from a bed.

[0007]

The present invention employs the following technical means to achieve the above object.

According to the first and second aspects of the present invention, in the bed monitor, the bed monitor is placed under, inside or on a surface of the bedding (11) laid on the bed (10) with a predetermined distribution. A plurality of load sensors (21) for outputting load signals corresponding to the load, a load signal processing circuit (31) for capturing the plurality of load signals, and a feature amount of the load distribution is calculated from the plurality of loaded signals. A characteristic amount calculating means, and the bed (1)
0) posture position calculating means for calculating the posture and position of the upper person, and signal generating means for determining a predetermined posture and position among the calculated postures and positions of the person and generating a notification signal (40).

[0009] The predetermined posture and position are characterized in that the person on the bed (10) is in an upright state of the upper body, or when the person is located on the left or right end side.

[0010] Thereby, the posture state of whether the person is sleeping or standing on the bed (10), or the position state of whether the person is on the center side or the left and right end sides of the bed (10) can be known, and in particular, the freedom of the body. The patient who does not respond to the bed (1
0) The notification signal is generated when the user gets up on the bed or when he / she is sleeping on the left and right ends of the bed (10), so that it is possible to prevent the user from accidentally falling off the bed (10). Can be. In addition, load sensor (2
Since 1) is placed on bedding, the device of the present invention can be used without the patient on the bed (10) noticing.

In the invention according to claim 3, the posture and position calculating means compares the result at the present time with the result before a predetermined time, and calculates the current posture and position of the person according to the state of change of both. It is characterized by the decision.

[0012] Thus, the slight movement of the patient, the position of the patient, and the careless load applied by the nurse are not directly calculated and determined as the current posture and position of the person. The complexity of the signal can be suppressed.

In the invention described in claim 4, the characteristic amount calculating means divides the plurality of load sensors (21) into a plurality of regions, and calculates the characteristic amount of the load distribution according to a load signal of each region. It is characterized in that it is calculated.

Thus, by capturing the load signal in each area, the posture and position of the person can be easily grasped without preparing a large number of feature models of the load distribution, and control programming is facilitated. . Further, the installation area of the plurality of load sensors (21) can be reduced, and the cost can be reduced.

According to a fifth aspect of the present invention, the plurality of load sensors (21) use a film pressure sensor (20).

[0016] Thus, the load sensor (21) can be mounted on a person without feeling uncomfortable.

According to a sixth aspect of the present invention, the notification signal is issued outside a region where the bed (10) is provided.

Thus, even if the nurse is in another room, the possibility of falling of the person on the bed (10) can be grasped and treatment can be performed.

The reference numerals in parentheses of the above means indicate the correspondence with the specific means described in the embodiment described later.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) FIG. 1 shows the overall configuration of a first embodiment of the present invention. The bed monitor device
Bed 10 provided in the sick room, bedding 11 laid on bed 10, sensor sheet 2 installed in bedding 11
0, a controller 30, and a nurse call 40 provided at a nurse center.

The sensor sheet 20 is provided with a plurality of pressure-sensitive elements (load sensors) 21 on a film, and is installed over almost the entire surface of the bedding 11. Here, the pressure-sensitive element 2
544 are provided at equal intervals. Pressure sensing element 21
Captures a resistance value that changes as a result of a load being distorted by a load. And the individual pressure-sensitive elements 21
Are wired so that a load signal is taken into a controller 30 described later.

The controller 30 receives a load signal (resistance value) from the pressure-sensitive element 21 and A / D converts the load signal into an actual load value. The controller 30 performs various processing based on the obtained load value. And an ECU 32 for calculating.

Further, a nurse call 40 provided at the nurse center is connected to the ECU 32, and generates a notification signal as needed.

A well-known nurse call switch 41 is provided at the bedside of the patient, and generates a call signal to the nurse call 40 according to the patient's will.

Next, the operation of the first embodiment will be described with reference to the flowchart shown in FIG. This flow mainly includes step S110 as a load distribution characteristic amount calculating unit and step S12 as a posture position calculating unit.
0 and step S130 as a signal generating means.

First, in step S50, initialization is performed. Here, the current posture is determined in step S125 described later.
The “non-occupied state” is input as initial data corresponding to the previous result required for determining the position.

In step S100, the load signal from the pressure-sensitive element 21 is taken into the load signal processing circuit 31, and is converted into an actual load value. Then, the process proceeds to step S110 to calculate the feature amount of the load distribution.

In step S111, it is determined whether or not the total load value ΔP obtained by adding all the load values obtained from the pressure-sensitive elements 21 is larger than a predetermined value a. If it is determined to be larger, it is determined that a patient is on the bed 10 and the process proceeds to step S112. If it is determined that there is no patient, it is determined that there is no patient, and the process returns to step S100 and repeats step S111. Here, the predetermined value a is obtained by correcting the weight value of the patient using the bed 10 and inputting it as a preset value.

In step S112, it is determined whether or not the load value obtained from each pressure-sensitive element 21 is greater than a predetermined value b. If it is determined to be larger, the process proceeds to step S113,
The position of the pressure-sensitive element 21 is recognized, and the sensor sheet 20 is detected.
The feature amount is calculated as the load distribution above. If it is determined to be no, no recognition process is performed, and step S121 is performed.
Proceed to. Here, the predetermined value b is a boundary value of a load value for determining that there is a load, and is input as a preset value similarly to the above a.

Next, the process proceeds to step S120 to calculate the posture and the position. In step S121, the feature models input in advance are extracted one by one. Here, the feature model is a model in which load distributions corresponding to various possible postures and positions of the patient on the bed 10 are displayed in an area corresponding to the sensor sheet 20 and input in advance as a large number of model data.

In step S122, the above-mentioned step S11
The feature amount obtained in step 3 and the feature model are matched one by one. That is, the most similar feature model is selected.

In step S123, it is determined whether or not all the matchings have been completed.
At 24, the posture and position of the feature model selected by matching are calculated as the current result. Step S12
If the matching is not completed in step 3, step S12
Repeat until 2 is complete.

In step S125, the current posture and position of the patient are determined from the previous result and the present result. That is, the map shown in FIG. 3 is input in advance, and the position where the previous result and the present result intersect on the map is determined as the current posture and position. For example, if the previous result is a sleeping state and the current result is a bed state, the current posture and position are changed from the crossover position to the rising state (here, the patient's upper body is up on the bed 10, or the patient is Is called a wake-up state), or left and right end sides. Incidentally, the previous result is a memory of the determination result obtained in the immediately preceding flow, and the current result is a memory of the determination result obtained in step S124. The previous result at the time of the first flow is the data input as the initial setting in step S50. Then, each time the flow rotates, the previous result is cleared and replaced with the present result. Further, the result obtained in the flow at that time is stored as the current result. This is repeated for each flow.

Further, the process proceeds to step S130 in order to generate a notification signal when the posture and the position are calculated and determined with respect to the predetermined posture and position.

The determined posture and position are the patient's wake-up state,
Alternatively, it is determined in step S131 whether the position is on the left or right end side. If the patient is in the wake-up state or at the left or right end, the patient may fall off the bed 10 by mistake.
A notification signal is generated in step S132. Specifically, the ECU 32 calculating this flow
The buzzer of the corresponding hospital room number of the nurse call 40 sounds. Note that if it is determined to be NO in step S131 (in cases other than the rising state and the left and right ends), there is no possibility that the patient falls down from the bed 10, and the process proceeds to step S133 without generating a notification signal.

In step S133, it is determined whether or not the elapsed time in this calculation is longer than a predetermined time τ, and if it is longer, the process returns to step S100 and the same calculation is repeated. If the answer is NO, the process waits until the predetermined time τ has passed, and then proceeds to step S1.
Return to 00.

With the above configuration and operation, the bed 10
Posture status of whether the patient is sleeping or standing up,
Alternatively, the user can know the position of the patient on the bed 10 at the center or on the left and right sides.
Since the notification signal is generated when the user tries to move away from zero or when the user is lying on the left and right ends of the bed 10, it is possible to prevent the user from falling off the bed 10 by mistake. In this case, since the notification signal is generated in the nurse call 40 in a nurse center different from the hospital room, the possibility of the patient falling on the bed 10 can be grasped and treated without the necessity of the nurse always attending the patient.

Further, since the sensor sheet 20 in the form of a film is set on the bedding, the apparatus of the present invention can be used without giving the patient on the bed 10 a sense of incongruity and without being noticed by the patient.

Further, the slight movement of the patient, the position of the patient, the careless load applied by the nurse, and the like are not directly calculated and determined as the current posture and position of the patient. Can be suppressed.

(Second Embodiment) FIGS. 4 to 6 show a second embodiment of the present invention. The second embodiment is different from the first embodiment in that the sensor sheet 20 is provided at a portion corresponding to mainly the upper body of the patient, and the pressure-sensitive element 21 is divided into a plurality of regions to calculate the characteristic amount of the load distribution. It is something to do.

As shown in FIG. 5, the sensor sheet 20 has a vertical dimension X corresponding to the patient's shoulder to waist and a bed 10.
A plurality of pressure-sensitive elements 21 are provided on a film having a horizontal dimension Y corresponding to the width of the film. Here, the pressure sensitive element 21 is 5 in the vertical direction, 22 in the left and right direction, a total of 110.
The pieces are provided so as to be distributed in a staggered arrangement. Furthermore,
Each pressure-sensitive element 21 is divided into two regions, an A region and a B region. Whether the position of each pressure-sensitive element 21 is the area A or the area B is input to the ECU 32 in advance. The A region is a region on the center side above the waist of the patient. The area B is an area below the patient's waist and on the left and right end sides.

Boundary line between A and B areas on the center side (A)
Is pulled in order to easily grasp whether the patient is in a sleeping state or a state in which the upper body is up. A, B
When the load applied to the area is equal to or more than the predetermined value, the state is considered to be a sleeping state, and when the load is applied intensively to the area B, the state is a load from the patient's waist and the state is up.

The border lines (A) and (C) of the A and B regions on the left and right end sides are drawn to easily grasp whether the patient is at the center or the left or right end when the patient is sleeping. .

Next, the operation of the second embodiment will be described with reference to the flowchart shown in FIG. As in the first embodiment, this flow also includes step S200 as a load distribution characteristic amount calculation unit, step S210 as a posture position calculation unit, and step S210 as a signal generation unit.
130. Since step S130 is the same as the first embodiment, steps S200 and S210 will be described in detail below.

First, in step S50, "non-occupied state" corresponding to the previous result is input as data as an initial setting.

In step S100, a load signal from the pressure-sensitive element 21 is fetched. Then, the process proceeds to step S200 to calculate the feature amount of the load distribution.

In step S201, it is determined whether the load value obtained from each pressure-sensitive element 21 is larger than a predetermined value b. If it is determined to be larger, the process proceeds to step S202,
If it is not, the process proceeds to step S205. Note that the predetermined value b is a boundary value similar to that of the first embodiment.

In step S202, it is determined whether or not a load value larger than the predetermined value b is in the region A. If it is A area,
In step S203, the number of the sensors is counted.
If not, the number of sensors in the area B is counted in step S204.

In step S205, in order to determine whether or not a patient is on the bed 10, it is determined whether or not the total load value ΔP obtained by adding all the load values obtained from the pressure-sensitive elements 21 is greater than a predetermined value c. Is determined. If it is determined to be larger, it is determined that a patient is on the bed 10 and the process proceeds to step S206. Here, the predetermined value c is a value obtained by correcting the weight value corresponding to the upper body of the patient using the bed 10 and inputting it as a preset value.

In step S206, the number obtained by adding a predetermined value d to the count in area A obtained in step S203 is used to determine whether the patient is in the upright state in the area B obtained in step S204. Determine if it is less than the number. If determined to be no, step S20
Go to 7. Here, the predetermined value d is a margin value provided in advance to reliably determine the rising state of the patient.

In step S207, the count number of the area A is set to a predetermined value e in order to determine whether the patient is sleeping.
It is determined whether or not the count value is larger than the predetermined value f. Here, the predetermined values e and f are boundary values provided in advance to reliably determine the sleeping state of the patient.

Next, the process proceeds to step S210 to calculate the posture and position. Here, the above steps S205 and S205
The posture and position of the patient are determined based on the determinations in steps 206 and S207, and the current result and position are determined by comparing the previous result with the present result in step S210.

In step S211, the above step S20
If the determination of No. 5 is negative, the non-occupied state is determined because the total load value is smaller than the predetermined value c.

In step S212, the above-mentioned step S20
If the determination of No. 6 is affirmative, the load is concentrated on the area B, so that the user gets up on the bed 10 or gets up from the bed 10, or
Is determined to be the left and right ends.

In step S213, the above-mentioned step S20
If the determination in step 7 is affirmative, the load is applied to both the region A and the region B, so that the sleep state is determined. If the determination in step S207 is NO, for example, the bed 10
, And is determined to be in the floor.

In step S215, the current posture and position of the patient are determined from the previous result and the present result. This is the same as step S125 of the flow in the first embodiment.

Further, the process proceeds to step S130 in order to generate a notification signal when the posture and the position are predetermined with respect to the calculated posture and position. This is also the same as in the first embodiment.

With the above configuration and operation, in addition to the effects of the first embodiment, by capturing the load signals in each area of the sensor sheet 20, it is not necessary to prepare a large number of load distribution feature models or the like in advance. Also, the posture and position of the patient can be easily grasped, and control programming becomes easy. Further, the installation area of the sensor sheet 20 can be reduced, and the cost can be reduced.

In the above embodiment, the posture and the position at which the notification signal is generated may be set according to the condition of the patient. For example, a warning signal may be generated only when the user is in a rising state as a dangerous movement such as falling off the bed 10.

The map shown in FIG. 3 may be determined in consideration of the patient's behavior pattern, sleeping habits, and the like.

Further, an area A provided on the sensor sheet 20;
The B region and the predetermined values e and f may be set arbitrarily, and may be set according to the physique difference of each individual patient and the demand for rising detection sensitivity. Of course, the position and number of the pressure-sensitive elements 21 may be set arbitrarily.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram according to a first embodiment of the present invention.

FIG. 2 is a flowchart illustrating an operation of a controller according to the first embodiment.

FIG. 3 is a map for determining a current posture and position.

FIG. 4 is a perspective view showing the periphery of a bed according to a second embodiment.

FIG. 5 is a plan view illustrating details of a sensor sheet according to a second embodiment.

FIG. 6 is a flowchart illustrating an operation of a controller according to the second embodiment.

[Explanation of symbols]

 10 Bed 11 Bedding 20 Sensor Sheet (Film Pressure Sensor) 21 Pressure Sensitive Element (Load Sensor) 30 Controller 31 Load Signal Processing Circuit 32 ECU 40 Nurse Call (Signal Generating Means) 41 Nurse Call Switch

Claims (6)

[Claims] A bed (1) laid on a bed (10).
1) installed in a predetermined distribution under, inside or on the surface,
A plurality of load sensors (21) for outputting a load signal corresponding to the applied load; and a load signal processing circuit (3) for capturing the plurality of load signals.
1) a feature amount calculating means for calculating a feature amount of a load distribution from a plurality of loaded load signals; and a posture / position calculation for calculating a posture and a position of a person on the bed (10) from the feature amounts of the load distribution. A bed monitor device comprising: means; and signal generation means (40) for determining a predetermined posture and position of the calculated person posture and position and generating a notification signal. 2. The bed monitor device according to claim 1, wherein the predetermined posture and position are when a person on the bed (10) is in an upper body upright state or when the person is located on the left and right end sides. 3. The posture and position calculating means compares a result at a present time with a result before a predetermined time, and calculates and determines a current posture and position of a person according to a change state of both. Item 3. The bed monitor device according to item 2. 4. The feature amount calculating means divides the plurality of load sensors (21) into a plurality of regions, and calculates the feature amount of the load distribution according to a load signal of each region.
3. The bed monitor device according to any one of 3. 5. The bed monitor device according to claim 1, wherein said plurality of load sensors (21) use a film pressure sensor (20). 6. The bed monitor according to claim 1, wherein the notification signal is issued outside a region where the bed is provided.