JPH0966077A - Human body detector for bed - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive and safe human body detector for a bed. SOLUTION: A first infrared ray sensor 3 is provided at specified height from a mattress 2 at the center of an end on the head side of the bed 1 and second infrared ray sensors 4 and 5 are provided on the left and right with an interval. The first infrared ray sensor 3 can selectively detect a human body lying at the center of the bed 1, the second infrared ray sensors 4 and 5 can respectively detect the human body standing at the side of the bed 1 and the presence/absence of the human body on the bed 1 are judged by comparing the detected output by a control circuit. That is, a cost is lowered since pyroelectric type elements for infrared ray detection can be used for the first and second infrared ray sensors 3, 4 and 5 and safety is improved as compared to the one requiring electrical wiring under the mattress such as a pressure sensor or the like because the human body is detected under non-contact state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a human body detecting device for beds.

[0002]

2. Description of the Related Art At present, in order to reduce the burden on the caregiver of having to always care whether the care recipient is in bed or not, a sheet-shaped pressure sensor is laid on the bed of the bed and the pressure sensor There are commercially available bed human body detection devices that notify the presence or absence of a person according to the output.

[0003]

However, since the use is medical, the bed is often wet, and it is necessary to take sufficient insulation measures, and the center is often used for medical purposes. It is necessary to ensure sufficient durability against bending in order to correspond to a bed in which the bed bends and the bed becomes a chair. In addition, it is difficult to reduce the cost because it is necessary to provide a large area pressure sensor that can be laid on the entire lower surface of the bed.

Further, there is a potential danger due to the presence of electrical wiring under the bed, and even if sufficient insulation measures are taken, such danger is eliminated from the viewpoint of durability with respect to aging. Difficult to do.

Therefore, an object of the present invention is to provide an inexpensive and safe bed human body detection apparatus.

[0006]

A first infrared sensor having a detection range on a bed, a second infrared sensor having a detection range laterally and above the bed, and first and second detection sensors.
The above-described object is achieved by a bed human body detection device including a determination means for determining the presence or absence of a human body on a bed according to the detection output of the infrared sensor.

Here, the number of pyroelectric infrared detecting elements forming the first infrared sensor is set to be larger than the number of pyroelectric infrared detecting elements forming the second infrared sensor, and / or the first infrared detecting element. By dividing the Fresnel lens, which determines the detection range of the infrared sensor, of the second infrared sensor into finer parts than the Fresnel lens that determines the detection range of the second infrared sensor, the first infrared sensor performs a smaller movement of the human body than the second infrared sensor. It is preferable to be able to detect.

Further, the first infrared sensor is provided at a specific height slightly higher than a human body lying on the bed from the bed at the head-side end of the bed and at the center in the width direction of the bed, and its detection range is vertical. In the range from horizontal to a specific depression angle including the human body who normally sleeps on the bed, in the left-right direction has a specific angle from the center of the length direction of the bed to the left and right, and the effective distance is limited to the bed. Further, a pair of second infrared sensors are provided on the left and right sides of the first infrared sensor, respectively, at specific intervals so as to avoid overlapping of the detection range with the first infrared sensor, and the detection range of each second infrared sensor. It is also preferable that both have a width from the horizontal to a specific elevation angle in the vertical direction and a range including at least the center of the bed side end portion and the outside thereof in the horizontal direction, and the effective distance is substantially the same as the length of the bed.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Next, a bed human body detecting apparatus according to an embodiment of the present invention will be described. FIG. 1 is an explanatory diagram for explaining the configuration of this example. 1a and 1b respectively show the plane and side surfaces of a bed equipped with the device of this example. Further, FIG. 2 is a view showing the bed as seen from the foot side.
In the above figures, 1 is a bed, and the height from the floor is 0.
A bed 2 having a length of 2.2 m and a width of 1.0 m is provided at a position of 6 m. Reference numeral 3 denotes a first infrared sensor, which is a pyroelectric type sensor, and is provided at a position 0.3 m above the bed 2 at the center of the head-side end of the bed 1. The height of this mounting position is not particularly limited to 0.3 m, and is based on the human body G lying on the bed 1 (indicated by the alternate long and short dash line in FIG. 1b, here, a human body with a height of about 1.6 m is shown). The height may be slightly higher.
The first infrared sensor 3 has a detection range A, and the detection range A
Has a width from the horizontal to the depression angle of 50 ° in the vertical direction, and has a width of 15 ° in the left-right direction from the center of the length direction of the bed 1 (arrow D), and an effective distance of about 1.5 m. is there. The detection range A is for detecting a state in which a human body is on the bed 1, and is a range defined so that a human body lying in the center of the bed 1 can be detected. 4,5
Is a second infrared sensor, which is of a pyroelectric type, and is provided on the left and right of the first infrared sensor 3 at intervals of 0.1 m. This is an interval for avoiding overlapping of the detection range with the first infrared sensor 3, and the interval is not limited to this and may be set appropriately. Second infrared sensor 4, 5
Have detection ranges B and C, respectively, and these detection ranges B and C
C extends from the attachment position to the upper side of the bed 1 so that a human body entering the bed 2 of the bed 1 from the side of the bed 1 can be detected. Here, the detection range B has a width from the horizontal to the elevation angle of 30 ° in the vertical direction, and the bed 1 in the horizontal direction.
15 ° to 45 ° to the right from the center of the length direction (arrow E)
The effective distance is 2.0 m. Similarly, the detection range C is from the horizontal to the elevation angle of 30 ° in the vertical direction, from the center of the length direction (arrow F) of the bed 1 to the left in the horizontal direction from 15 ° to 45 °, and the effective distance is about 2.0 m. Is. The vertical angular widths of the detection ranges of these second infrared sensors are not limited to those described above, and a human body standing beside the bed depending on the mounting position of the second infrared sensor, for example, human body H.
(It is indicated by the chain double-dashed line in FIG. 1b and the standing state of the human body shown in G is shown.) May be appropriately set so that the angular width in the left-right direction can be similarly detected. Not limited to the above, in order to be able to detect the human body standing beside it while trying to enter the bed of the bed, including at least the center of the side end of the bed, preferably, to cross more than half of the side end of the bed appropriately Just set it.

Next, details of the first and second infrared sensors 3 to 5 will be described. For example, the first infrared sensor 3
Is a front view, b is a left side view, and c is shown in FIG.
Shows a cross section taken along line I-I of FIG. ), An infrared sensor 31 including a pyroelectric infrared detection element
Is covered with a housing 33 that masks a portion other than the portion 32 corresponding to the detection range. A Fresnel lens 34 is provided in the portion 32 corresponding to the detection range. The Fresnel lens 34 is provided corresponding to the lower half of the infrared sensor 31, and has a condensing range of 30 ° in the left-right direction and 50 ° from the horizontal in the vertical direction with the center of the infrared sensor 31 as the center. The above-mentioned detection range A is defined. Although not particularly shown, the second infrared sensors 4 and 5 are also the same.
An infrared sensor is provided inside a housing provided with a Fresnel lens corresponding to each detection range. In the case of the second infrared sensors 4 and 5, the Fresnel lens is provided corresponding to the upper half of the infrared sensor, and in the second infrared sensor 4, the center of the infrared sensor is the center and the angle is 15 ° to the right.
.About.45.degree., And the second infrared sensor 5 is set to have a condensing range of 15.degree. To 45.degree. In the left direction and 30.degree. In the vertical direction with the center of the infrared sensor as the center. Here, the Fresnel lens 34 of the first infrared sensor 3 is
The infrared sensors 4 and 5 are divided more densely than that of the infrared sensors 4 and 5, and can detect a smaller motion of the human body. Further, the infrared sensor 3 used for the first infrared sensor 3
1 is composed of four pyroelectric infrared detecting elements 35 arranged in 2 rows and 2 columns as shown in FIG. 4a. Although not shown, these pyroelectric infrared detecting elements 35 are connected in series. Four
Output is produced in response to the vertical, horizontal, and diagonal movements indicated by arrows J to M of a. The infrared sensor 36 used for the second infrared sensors 4 and 5 is composed of two pyroelectric infrared detecting elements 37 as shown in FIG. 4b.
As shown by an arrow N in the figure, a pyroelectric infrared detection element 36
An output is generated in response to the horizontal movement of the lines. Since the setting is made in this way, the first infrared sensor 3 can detect a multidirectional movement smaller than the second infrared sensors 4 and 5, that is, a slight movement.

Next, the circuit configuration of this example will be described with reference to FIG. Similar to the above figure, 3 is a first infrared sensor, and 4 and 5 are second infrared sensors. Reference numeral 6 denotes a control circuit as a determination means, which includes the first and second infrared sensors 3
The output of ~ 5 is received, and the presence or absence of the human body on the bed 1 is determined according to these. For example, although not shown, the control circuit 6 has a waveform shaping section, a comparison section, etc., removes unnecessary noise components from the outputs of the first and second infrared sensors 3 to 5, and appropriately amplifies them. By comparing with a predetermined threshold value, it is processed as a detection output of the motion of the human body in each detection range, and the presence or absence of the human body on the bed 1 is determined based on these. Further, the sensitivity of the first and second infrared sensors 3 to 5, that is, the above-mentioned effective distance is set by adjusting the amplification factor. A display unit 7 displays the presence / absence of a human body on the bed 1. At least the display unit 7 is provided at the nursing station.

Next, the operation of this example will be described with reference to the flowchart of FIG. First, the human body is in bed 1
The operation in the above case will be described with reference to the flowchart of FIG. 6a. In this case, there is a human body on the bed 1, for example, the person is sleeping on the bed 1, and from this state, the action of the person getting out of the bed 1 is determined. Here, it is assumed that the control circuit outputs while holding the state in which the human body is on the bed 1, and that fact is displayed on the display unit 7.
First, it is determined whether or not there is an output from the first infrared sensor 3 (step 1a). Here, if the person does not move within the detection range A, no output is produced from the first infrared sensor 3, and the state where the human body is on the bed 1 is held by the control circuit 6 (step 1b). On the other hand, here, if a person moves within the detection range A, an output is generated from the first infrared sensor 3. When this output is received, it is determined whether or not there is an output from the second infrared sensors 4 and 5 (step 1c). That is, the detection range A
After a slight movement detected in step S1, it is determined whether or not a person gets up and enters the detection ranges B and C. Here, unless a person gets up and the human body does not enter the detection range B or the detection range C, the outputs of the second infrared sensors 4 and 5 do not occur. In this case, the operations from step 1a onward are repeated. Here, if a person gets up and the human body enters the detection range B or the detection range C, the second infrared sensor 4 or the second infrared sensor 4 is detected.
An output is generated from the infrared sensor 5 of. Upon receiving this output, the control circuit 6 determines whether or not there is an output from the first infrared sensor 3 (step 1d). Here, the first infrared sensor 3 can detect a slight movement than the second infrared sensors 4 and 5, and when a person gets up and the second infrared sensors 4 and 5 emit an output, the detection range If there is a human body in A, the first infrared sensor 3 emits an output. In this case, the operations from step 1c are repeated until the output of the first infrared sensor 3 is cut off, and the person temporarily gets up on the bed 1 and enters the detection ranges B and C, so that the person leaves the bed 1. Avoid judging that Here, when the person leaves the detection range A in step 1d and the output of the first infrared sensor 3 is cut off, the person
It is determined that the human body is not on the bed 1, and the state in which the human body is not on the bed 1 is output and held (step 1e). In response to this, the display unit 7
Changes the display to that there is no human body.

Next, the operation when the human body is not on the bed 1 will be described with reference to the flowchart of FIG. 6b. In this case, it is determined whether the person enters the bed 1. Here, the control circuit 6 holds and outputs the state where the human body is not on the bed 1. First, the second infrared sensors 4, 5
The presence or absence of the output of is determined (step 2a). Here, if there is no output from the second infrared sensors 4 and 5, the output when the human body is not on the bed 1 is held (step 2b).
On the other hand, here, when a human body enters the detection range B or the detection range C, an output is generated from the second infrared sensor 4 or the second infrared sensor 5. When this is received, the presence or absence of the output of the first infrared sensor 3 is determined (step 2c). Here, if the human body does not enter the detection range A, the output of the first infrared sensor 3 is not generated, and the operation of step 2a and thereafter is repeated. On the other hand, here, when the human body enters the detection range A,
When an output is generated from the first infrared sensor 3 and the output is received, the control circuit 6 thereafter considers that it takes about 30 seconds for all the human body to stay within the detection range A on the bed 1
Within 5 minutes, here 1 minute, the second infrared sensor 4, 5
Determines that no output is generated again (step 2
d). That is, it is determined that the person enters the bed 1 when the person is detected in the detection range A and is not detected in the detection ranges B and C for a certain time thereafter. here,
If there are outputs from the second infrared sensors 4 and 5, it is determined that the human body is still on the side of the bed 1 and the process returns to step 2c to repeat the above steps. That is, by repeating this, for example, it is determined that the person has moved into the bed 1 by an action such as a person standing beside the bed 1, picking up an object on the bed 2 and leaving the place. Avoid it. Here, if there is no output from the second infrared sensors 4 and 5 in step 2d, it is assumed that the human body has entered the bed 1 and the state where the human body is on the bed 1 is output and held (step 2e).

As described above, in this embodiment, the presence or absence of the human body on the bed 1 can be determined without contact, so that it is possible to eliminate the cost increase and the risk which are present in the conventional one.

Since the detection range A of the first infrared sensor 3 and the detection ranges B and C of the second infrared sensors 4 and 5 are determined as described above, the respective sensors lie on the bed 1. It is possible to obtain a detection output of a person's movement, a detection output of a movement of a person standing upright on one of the left and right ends of the bed 1, or standing on the side, and by comparing these output states as described above, Determines whether the person leaves the bed 1 or enters the bed 1, and based on this, continuously outputs the state of the presence or absence of a human body on the bed 1. This makes it possible to accurately and continuously output the presence / absence of a human body on the bed 1 even if a pyroelectric infrared detection element that cannot detect a stationary body is used. In addition, the first infrared sensor 3 that detects the motion of the person sleeping on the bed 1 divides the Fresnel lens 34 that defines the detection range into the second infrared sensors 4 and 5.
Since it is denser than that of the above and the number of pyroelectric infrared detecting elements is increased, it is possible to detect a slight movement of a person, and it is possible to monitor a human body sleeping on the bed 1 more continuously. is there. For this reason, since the above-mentioned processing is performed according to the output, the determination accuracy can be improved as a whole while simplifying the second infrared sensors 4 and 5, and the cost can be reduced.

Further, since the first infrared sensor 3 and the second infrared sensors 4 and 5 are arranged side by side, they can be housed in one package, in which case the cost for mounting can be reduced.

In the above embodiment, the first infrared sensor 3 is provided at the center of the head-side end of the bed 1, and the second infrared sensors 4 and 5 are provided on both sides of the first infrared sensor 3. However, the present invention is not limited to this. . For example, it may be provided on the foot side of the bed 1. That is, the position where the first infrared sensor is provided may be a position where the human body lying in the center of the bed can be detected. For example, the first infrared sensor is placed at an appropriate position around the bed, for example, in the frame at the side of the bed. The first infrared sensor may be provided at a position slightly higher than the human body in the state, and the detection range may be determined toward the center of the bed. In addition, a plurality of first infrared sensors having different detection ranges may be provided. For example, the first infrared sensor has a common detection range in a vertical direction from a position slightly higher than a human body in a sleeping state to the bed, and differs in a horizontal direction. A plurality of first infrared sensors having a detection range may be provided side by side with the center of the bed at the left and right ends of the bed. Further, the position where the second infrared sensor is provided may correspond to the position where a person goes in and out, and if it is used for a bed having a fence around it, the second infrared sensor should be moved toward a part without a fence for getting off the person. Infrared sensor is installed to avoid overlapping with the detection range of the first sensor.
Moreover, the detection range expanded upward may be set so as to include the human body standing beside the part without the fence. For example, if a fence is provided on either the left or right side of the bed of the above embodiment, the second infrared sensor on that side need not be provided.

[0018]

According to the present invention, the presence or absence of a human body on the bed can be determined in a non-contact manner, so that it is possible to eliminate an increase in cost, which is conventionally required, and to improve safety.

Further, the first infrared sensor obtains the detection output of the human body on the bed, the second infrared sensor obtains the detection output of the human body on the side and above the bed, and the detection output of the human body on the bed is obtained according to these detection outputs. Since the presence / absence of the human body is determined, the presence / absence of the human body on the bed can be determined with high accuracy by using the pyroelectric infrared detection element.

Further, the Fresnel lens which determines the detection range of the first infrared sensor by increasing the number of pyroelectric infrared detection elements constituting the first infrared sensor more than that of the second infrared sensor, If the first infrared sensor can detect a slight movement of the human body than the second infrared sensor by dividing the detection range of the second infrared sensor more finely than the Fresnel lens, the determination accuracy is improved as a whole. In addition, the configuration of the second infrared sensor can be simplified and the cost can be reduced.

When the first infrared sensor is provided at the center of the head-side end of the bed and the second infrared sensors are provided on the left and right sides of the first infrared sensor, and the respective detection ranges are defined as defined in claim 3, The first infrared sensor can detect a human body lying on the bed, and the left and right second infrared sensors can detect a human body on either the left or right side of the bed. As a result, it is possible to reliably capture the movement of a person who enters or leaves the bed from either the left or right side of the bed, and it is possible to accurately determine the presence or absence of a human body on the bed.

[Brief description of drawings]

FIG. 1 is an explanatory diagram for explaining a configuration of an embodiment of the present invention.

FIG. 2 is an explanatory diagram for explaining a configuration of an embodiment of the present invention.

FIG. 3 is an explanatory diagram for explaining a main part of FIG. 1.

FIG. 4 is an explanatory view for explaining a main part of FIG.

FIG. 5 is a block diagram for explaining the configuration of an embodiment of the present invention.

FIG. 6 is a flowchart for explaining the operation of FIG.

[Explanation of symbols]

 1 bed 2 bed 3 first infrared sensor 4, 5 second infrared sensor 6 control circuit (determination means)

Claims (3)

[Claims] 1. A first infrared sensor having a detection range on the bed, a second infrared sensor having a detection range laterally and above the bed, and detection outputs of the first and second infrared sensors. A human body detection device for a bed, comprising: a determination unit that determines whether or not a human body is present on the bed. 2. The number of pyroelectric infrared detecting elements constituting the first infrared sensor is made larger than the number of pyroelectric infrared detecting elements constituting the second infrared sensor and / or By dividing the Fresnel lens that determines the detection range of the infrared sensor into smaller pieces than the Fresnel lens that determines the detection range of the second infrared sensor, the first infrared sensor detects a smaller movement of the human body than the second infrared sensor. The human body detecting device for a bed according to claim 1, wherein the human body detecting device for a bed is provided. 3. The first infrared sensor is provided at a specific height, which is slightly higher than a human body lying on the bed from the bed at the head-side end of the bed, and at the center in the width direction of the bed, and the detection range thereof is the vertical direction. In the range from horizontal to a specific depression angle including the human body who normally sleeps on the bed, in the left-right direction has a specific angle from the center of the length direction of the bed to the left and right, and the effective distance is limited to the bed. Further, a pair of second infrared sensors are provided on the left and right sides of the first infrared sensor, respectively, at specific intervals so as to avoid overlapping of the detection range with the first infrared sensor, and the detection range of each second infrared sensor. Both have a width from the horizontal to a specific elevation angle in the vertical direction and a range including at least the center of the bed side end and the outside thereof in the horizontal direction, and the effective distance is almost the same as the length of the bed. Claim 1 Human body detector for beds.