JP2018075183A - Biological information detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a biological information detector for accurately calculating a centroid position of a person on a sleeping stand depending on a displacement of a load center of a base of a bed with rise and fall of the sleeping stand.SOLUTION: A biological information detector T in a bed B1 comprising a base 20, a sleeping stand having a first reference point K1 in a first coordination system for defining a centroid position of a person existing on a top surface 32a, and a lifting device 40 for rising/falling as a load center of the base 20 is displaced in a horizontal direction comprises: a second person centroid position calculation unit 12 that, in a second coordination system taking a second reference point K2 with respect to the base 20 as a reference, calculates a person centroid position of the person on the sleeping stand 30 from detected loads detected by a plurality of load sensors 5a, 5b, 5c, 5d; and a correction unit 13 that, on the basis of a relative displacement amount between the second reference point K2 and the first reference point K1 caused by rise and fall of the sleeping stand 30, corrects a calculated second person centroid position represented using the second coordination system to a first person centroid position represented using the first coordination system.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a biological information detection apparatus.

  There has been proposed a technique for detecting biological information of a person existing on a bed based on a load applied to the bed. For example, in the in-situ state detection device described in Patent Document 1, a plurality of load sensors for detecting loads are provided on four legs of the bed. Then, the occupancy status detection device calculates the position of the center of gravity of the person present in the bed based on the load detected by the load sensor. Then, when the person's center-of-gravity position is located within the monitoring region set in the bed portion, the occupancy status detection apparatus outputs an alarm.

  Patent Document 2 describes a bed that is suitably used in a nursing facility or a nursing facility and that has a load detection function that can adjust the height of a bed for a person to sleep. In a bed with a load detection function, a plurality of load sensors are arranged at a plurality of predetermined positions on a base that supports the bed so that it can be moved up and down. The bed with a load detection function includes a calculation unit, and the calculation unit calculates the position of the center of gravity of a person existing on the bed based on the load detected by the load sensor.

JP 2014-128695 A JP2013-148520A

  In care facilities and nursing homes, a bed with a load detection function that can be adjusted in height by combining the techniques of Patent Document 1 and Patent Document 2 is used according to the position of the center of gravity of the person on the bed. A configuration capable of outputting an alarm is desired.

  However, a bed that can be adjusted in height may use an elevating mechanism that adjusts the height of the bed while swinging in the longitudinal and width directions of the bed when the bed is raised and lowered. This type of bed has a load center that is the center of the distribution of the load applied to the base when the bed is moved up and down, the sleeping part moves in the horizontal direction relative to each load sensor arranged on the base. Is displaced in the horizontal direction. For this reason, in the bed with a load detection function capable of adjusting the height, there has been a problem that the calculated center of gravity position of the person and the actual center of gravity position of the person are misaligned.

  Therefore, the present invention can accurately calculate the actual center-of-gravity position of a person existing on the bed even if the center of load applied to the bed base is displaced in the horizontal direction as the bed is raised or lowered. It is an object to provide a biological information detection device.

  In order to solve the above-described problem, a biological information detection apparatus according to claim 1 defines a base, an upper surface disposed above the base, on which a person can exist, and a gravity center position of the person existing on the upper surface. A bed having a first reference point serving as a reference for the first coordinate system, and a bed that is provided between the bed and the bed so that a load applied to the bed can be transmitted to the bed A lifting device that lifts and lowers the bed while the center of load, which is the center of the distribution of the load applied to the base when the bed without a person on the upper surface moves up and down, is displaced horizontally, A biological information detection device applied to a bed provided with a plurality of load sensors provided at a plurality of predetermined locations on a base and for detecting a load applied to each predetermined location, and a plurality of load sensors, respectively. Sleeping from multiple detected loads that are each detected load A second person centroid position calculating unit that calculates a person centroid position, which is a centroid position of the person existing on the upper surface, in a second coordinate system based on the second reference point related to the base, and a second person centroid position Based on the relative displacement amount of the first reference point with respect to the second reference point that is generated as the lifting device is moved up and down, the second person center of gravity position represented by the second coordinate system calculated by the position calculation unit is used. A correction unit that corrects the position of the center of gravity of the first person, which is the position of the center of gravity of the person represented in one coordinate system.

  According to this, the second person centroid position calculation unit calculates the person centroid position, which is the centroid position of the person existing on the upper surface of the bed, from the plurality of detected loads that are the respective loads detected by the plurality of load sensors. The calculation is performed in the second coordinate system with the second reference point related to the base as a reference. The correction unit is configured to calculate the second person's center of gravity position represented by the second coordinate system calculated by the second person's center of gravity position calculating unit with respect to the second reference point generated with the lifting and lowering of the lifting device. Based on the relative displacement amount, the first person center of gravity position, which is the person center of gravity position represented in the first coordinate system, is corrected. In this way, the first person gravity center position where the second person gravity center position represented by the second coordinate system calculated by the second person gravity center position calculation unit is the person gravity center position represented by the first coordinate system. It becomes possible to correct to. Therefore, even if the center of load applied to the base is displaced in the horizontal direction as the bed is moved up and down, a living body information detection apparatus capable of accurately calculating the actual center of gravity position of a person existing on the bed is provided. can do.

It is the schematic which shows the biological information detection apparatus which concerns on 1st embodiment of this invention. It is a schematic plan view of the bed shown in FIG. It is a top view which shows the actuator used for the bed shown in FIG.1 and FIG.2. It is a schematic explanatory drawing of the horizontal movement of the bed accompanying the raising / lowering of the bed of the bed shown in FIG. It is a block diagram which shows the structure of the biometric information detection apparatus of 1st embodiment. It is a figure which shows an example of calculation of the 2nd person's gravity center position of the person who exists in the upper surface of the bed bed shown in FIG. It is a figure which shows an example which correct | amends the 2nd person gravity center position represented by the 2nd coordinate system of the bed shown in FIG. 1 to the 1st person gravity center position represented by a 1st coordinate system. It is a flowchart which shows the human gravity center position correction process performed with the biometric information detection apparatus of 1st embodiment. It is a block diagram which shows the structure of the other biological information detection apparatus of 1st embodiment. It is a flowchart which shows the 1st modification of the human gravity center position correction process performed with the other biometric information detection apparatus shown in FIG. It is a figure which shows an example of the correlation displacement amount detection part used for the other biological information detection apparatus shown in FIG. It is the schematic which shows the biometric information detection apparatus which concerns on 2nd embodiment of this invention. It is a schematic plan view of the bed shown in FIG. It is a block diagram which shows the structure of the biometric information detection apparatus of 2nd embodiment. It is a flowchart which shows the 2nd modification of the human gravity center position correction process performed with the biometric information detection apparatus of 2nd embodiment. It is a figure which shows an example which correct | amends the 2nd person gravity center position represented by the 2nd coordinate system of the bed shown in FIG. 11 to the 1st person gravity center position represented by a 1st coordinate system. It is a schematic side view which shows the mattress apparatus used for the bed shown in 1st embodiment or 2nd embodiment. It is a schematic plan view which shows the mattress apparatus shown in FIG. It is a schematic side view explaining the action | operation of the mattress apparatus shown in FIG.

<First embodiment>
A biological information detection apparatus according to a first embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, the biological information detection apparatus T is applied to a bed B1.

  As shown in FIGS. 1 and 2, the bed B1 includes a base 20, a bed 30, a lifting device 40, and load sensors 5a, 5b, 5c, and 5d. The base 20 has a frame structure having a rectangular shape in plan view. The base 20 includes a pair of left and right left side frames 21a extending in the front-rear direction, a right side frame 21b, a front frame 22a extending in the left and right direction, an intermediate frame 22b, and a rear frame 22c.

  The front end of the left side frame 21a is connected to the left end of the front frame 22a. The rear end of the left frame 21a is connected to the left end of the rear frame 22c. The front end of the right frame 21b is connected to the right end of the front frame 22a. The rear end of the right frame 21b is connected to the right end of the rear frame 22c. The left end portion of the intermediate frame 22b is connected to the inner surface of the left-side frame 21a at the front-rear intermediate position. The right end portion of the intermediate frame 22b is connected to the inner surface of the frame at the front and rear intermediate positions of the right frame 21b.

  The base 20 includes leg portions 23a, 23b, 23c, and 23d at the four corners of the front, rear, left, and right, respectively. The upper end of the leg part 23a is connected to the connection part of the left side frame 21a and the front frame 22a. The upper end of the leg portion 23b is connected to a connection portion between the right side frame 21b and the front frame 22a. The upper end of the leg portion 23c is connected to a connection portion between the left side frame 21a and the rear frame 22c. The upper end of the leg portion 23d is connected to a connection portion between the right side frame 21b and the rear frame 22c.

  Each of the load sensors 5a, 5b, 5c, 5d is provided at a plurality of predetermined locations on the base 20 and detects a load applied to the base 20. A load sensor 5a is disposed between the leg portion 23a and the floor U. A load sensor 5b is disposed between the leg portion 23b and the floor U. A load sensor 5c is disposed between the leg 23c and the floor U. A load sensor 5d is disposed between the leg 23d and the floor U. For example, each load sensor 5a, 5b, 5c, 5d uses a well-known strain gauge and outputs a load signal (voltage signal) that detects a load. Note that pressure-sensitive rubber can be used as the load sensor, and is not limited to the strain gauge. The load sensors 5a, 5b, 5c, and 5d are electrically connected to the input unit 11 of the control device 10 by wire or wirelessly.

  The bed 30 is disposed above the base 20. The bed 30 includes a frame portion 31 and a mattress 32 provided on the frame portion 31. The frame part 31 has a rectangular shape in plan view. The frame portion 31 includes a pair of left and right left frames 31a extending in the front-rear direction, a right frame 31b, a headboard 33 extending in the left-right direction, a horizontal frame 31c, and a rear vertical plate frame 34.

The front end of the left frame 31 a is connected to the lower left end of the head board 33. The rear end of the left frame 31 a is connected to the lower left end of the vertical plate frame 34. The front end of the right frame 31 b is connected to the lower right end of the head board 33. The rear end of the right frame 31 b is connected to the lower right end of the vertical plate frame 34. The left end of the horizontal frame 31c is connected to the inner side surface of the left and right frames 31a at the front and rear intermediate positions. The right end of the horizontal frame 31c is connected to the inner surface of the frame at the front and rear intermediate positions of the right frame 31b.
The frame portion 31 of the bed 30 includes a floor plate 31d (see FIG. 2). The mattress 32 is placed on the floor board 31d. The mattress 32 has an upper surface 32a where a person can exist.

The lifting device 40 is provided between the base 20 and the bed 30. The lifting device 40 lifts and lowers the bed 30 relative to the base 20 in a horizontal direction so that a load applied to the bed 30 can be transmitted to the base 20. The lifting device 40 is configured to move up and down while the load center, which is the center of the distribution of the load applied to the base 20 when the bed 30 on which no person is present on the upper surface 32a moves up and down, is displaced in the horizontal direction.
The lifting device 40 includes four lifting mechanisms 40a, 40b, 40c, and 40d, and an actuator 45 that drives the lifting mechanisms 40a, 40b, 40c, and 40d.

  A left front lifting mechanism 40 a is provided at the left front position of the base 20. A front right raising / lowering mechanism 40 b is provided at the right front side position of the base 20. A left rear elevating mechanism 40 c is provided at the left rear side position of the base 20. A right rear lifting mechanism 40 d is provided at the right rear position of the base 20. The left front lifting mechanism 40a and the right front lifting mechanism 40b have a symmetrical structure. The left rear elevating mechanism 40c and the right rear elevating mechanism 40d have a bilaterally symmetric structure. Each lifting mechanism 40a, 40b, 40c, 40d has basically the same structure except that the mounting positions are different.

The configuration of each lifting mechanism 40a, 40b, 40c, 40d will be described focusing on the left front lifting mechanism 40a at the left front side position of the base 20. The left front lifting mechanism 40 a includes a lower arm 41, an intermediate arm 42, and an upper arm 43. The lower end of the lower arm 41 is fixed to the upper surface of the left side frame 21 a of the base 20, and the lower arm 41 extends upward from the upper surface of the left side frame 21 a of the base 20. One end of the intermediate arm 42 is rotatably connected to the upper end of the lower arm 41. A connecting portion 421 between the lower arm 41 and the intermediate arm 42 is rotatably connected by a pin. Also, the other end of the intermediate arm 42 is rotatably connected to the lower end of the upper arm 43, and a connecting portion 422 between the intermediate arm 42 and the upper arm 43 is rotatably connected by a pin.
The upper end of the upper arm 43 is fixed to the left frame 31a of the bed 30 and extends downward.

As shown in FIG. 3, the actuator 45 includes a ball screw mechanism 451, an electric motor 452, a gear portion 453, and a telescopic rod 454 connected to the ball screw mechanism 451. The ball screw mechanism 451 includes a ball screw 451a and a nut portion 451b screwed into the ball screw 451a. The telescopic rod 454 is connected to the nut portion 451b. The gear portion 453 is configured to transmit the driving force of the electric motor 452 to the ball screw 451a. In the actuator 45, the ball screw 451a rotates clockwise or counterclockwise by driving the electric motor 452. Then, as the nut portion 451b reciprocates along the ball screw 451a, the telescopic rod 454 reciprocates.
As shown in FIGS. 1 and 2, the actuator 45 is arranged in a standing posture at a substantially central position of the base 20 and the bed 30 in a plan view. A base end 455 of the actuator 45 is rotatably connected to the horizontal frame 31c of the bed 30. The distal end 456 of the telescopic rod 454 of the actuator 45 is rotatably connected to the intermediate frame 22b of the base 20.

The raising / lowering of the bed 30 by the raising / lowering apparatus 40 is demonstrated. The bed 30 shown by the solid line in FIG. 1 shows a state where the bed 30 is lowered to the lowest lowered position Pdw. In this state, the intermediate arm 42 of the elevating device 40 takes a substantially horizontal posture. The actuator 45 of the elevating device 40 is contracted by the movement of the nut portion 451b accompanying the rotation of the ball screw 451a (see FIG. 3).
And the raising / lowering apparatus 40 expands the actuator 45 by the movement of the nut part 451b accompanying rotation of the ball screw 451a of the actuator 45, and raises the bed 30 to the highest rise position Pup. Along with this, the intermediate arms 42 of the elevating mechanisms 40a, 40b, 40c, 40d rotate around the connecting portion 421. At this time, the bed 30 is raised while maintaining a horizontal posture. In this case, the bed 30 is lifted along an arcuate trajectory in which the upper end of the intermediate arm 42 moves around the connecting portion 421.

The rising bed 30 also moves forward in the horizontal direction. For example, as shown in FIG. 4, the bed 30 (see FIG. 1) is assumed to move on a circular arc having a radius r from the base point PB1 in FIG. In this case, the bed 30 moves from the base point PB1 by the distance L in the horizontal direction as it rises to the lift position PI1. When the bed 30 is moved from the base point PB1 to the lift position PI2 on the vertical line, the moving distance in the horizontal direction becomes zero.
Further, the bed 30 moves from the base point PB2 in the drawing on the arc having the center A as the center of rotation and the radius r by a distance L in the horizontal direction from the base point PB2 in accordance with the ascent to the lift position PI3.
The distance L of the horizontal movement accompanying the elevation can be obtained from the following equation (1) and equation (3) derived from equation (2).

  When the bed 30 moves forward in the horizontal direction due to the rise of the bed 30, the load on the bed 30 applied to the front legs 23 a and 23 b increases on the base 20. Thereby, the load center which is the distribution center of the load applied to the base 20 (also simply referred to as the load center of the base 20) is displaced forward. The load distribution means that the load acting on the base 20 from the sleeping bed 30 acts in a distributed manner on the four legs 23a, 23b, 23c, and 23d of the base.

In the bed B1, the bed 30 (see FIG. 1) has a first coordinate system (see FIG. 6B) that defines the position of the center of gravity of the person existing on the upper surface 32a of the bed 30 with respect to detection of the position of the center of gravity of the person. For example, the first coordinate system represents the coordinates of the center of gravity position of the person on the upper surface 32 a of the bed 30. In addition, the bed 30 has a first reference point K1 (see FIG. 6B) that serves as a reference for the first coordinate system.
On the other hand, the base 20 calculates the person's center of gravity position, which is the position of the center of gravity of the person existing on the upper surface 32a of the bed 30, and the second reference point K2 (see FIG. 6B) related to the base 20 and the first A second coordinate system having the two reference points K2 as a reference is provided.

Based on FIG. 5, the electrical block configuration of the biological information detection apparatus T (see FIG. 1) will be described.
The biological information detection device T is a device applied to the bed B1 (see FIG. 1). The biological information detection device T is a device that detects biological information. The biometric information is information such as determination as to whether the upper person present on the bed 30 of the bed B1 is sleeping or awake, body movement during sleep of the person, sleep depth, heart rate, and the like. In addition, the biological information detection device T detects the position of the center of gravity of the person present on the bed 30. The biological information detection device T includes a CPU, and detects the position of the center of gravity of a person through program processing.

  The biological information detection device T includes a horizontal direction displacement amount detection unit 60 that detects the amount of displacement in the horizontal direction of the control device 10, the plurality of load sensors 5a, 5b, 5c, and 5d and the bed 30 (see FIG. 1). I have. The control device 10 includes an input unit 11, a second person gravity center position calculation unit 12, a correction unit 13, an input unit 14, a first relative displacement amount calculation unit 15, and a communication device 16.

  The horizontal displacement detection unit 60 detects the horizontal displacement of the bed 30. The horizontal displacement amount detection unit 60 is provided at the front portion of the base 20 of the bed B1 (see FIG. 1). The horizontal displacement amount detection unit 60 is fixed to the tip of an extension member 61 that extends upward from the front portion of the base 20. The horizontal displacement amount detection unit 60 detects a distance L in the horizontal direction from the measurement unit 62 provided below the headboard 33 of the bed 30. The horizontal direction displacement detection unit 60 is, for example, a known optical distance sensor. The horizontal displacement amount detection unit 60 is electrically connected to the input unit 14 of the control device 10 by wire or wireless.

The input unit 11 acquires the detected loads W1, W2, W3, and W4 output from the load sensors 5a, 5b, 5c, and 5d. The input unit 11 outputs the acquired detected loads W1, W2, W3, and W4 to the second person gravity center position calculating unit 12.
The input unit 14 acquires the distance signal output from the horizontal direction displacement amount detection unit 60. The input unit 14 outputs the acquired distance signal to the first relative displacement amount calculation unit 15.

  The second person center-of-gravity position calculation unit 12 generates a bed 30 (see FIG. 1) from a plurality of detected loads W1, W2, W3, and W4 that are loads detected by the plurality of load sensors 5a, 5b, 5c, and 5d, respectively. ) Is calculated by a second coordinate system based on the second reference point K2 (see FIG. 6B) related to the base 20 (see FIG. 1B). To do. The second person center-of-gravity position calculation unit 12 acquires the detected loads W1, W2, W3, and W4 output from the input unit 11. The second person center-of-gravity position calculation unit 12 calculates the second person center-of-gravity position according to the magnitude of each of the detected loads W1, W2, W3, and W4 acquired when a person is present on the bed 30.

For example, an example of calculating the second person center of gravity position will be described. As shown in FIG. 6A, in a plan view of the bed B1, the load sensor 5a is arranged on the left side of the head side of the bed B1. The control device 10 acquires the detection signal from the load sensor 5a as the detected load W1. The load sensor 5b is disposed on the right side of the head side of the bed B1. The control device 10 acquires the detection signal from the load sensor 5b as the detected load W2. The load sensor 5c is disposed on the left side of the foot side of the bed B1. The control device 10 acquires a detection signal from the load sensor 5c as a detected load W3. The load sensor 5d is disposed on the right side of the foot part side of the bed B1. The control device 10 acquires a detection signal from the load sensor 5d as a detected load W4. The bed B1 is set with the X axis in the second coordinate system along the front-rear direction, the Y axis in the second coordinate system is set along the left-right direction of the bed B1, and the left side of the head is the second reference point K2. Is set to The second person center-of-gravity position MG1 of the person M is calculated by the following equation (4). d1 is the longitudinal length of the bed 30. d2 is the width dimension of the bed 30.

  The correction unit 13 generates a second person barycentric position represented by the second coordinate system calculated by the second person barycentric position calculation unit 12 as the lifting device 40 (see FIG. 1) moves up and down. Based on the relative displacement amount of the first reference point K1 (see FIG. 6B) with respect to the reference point K2 (see FIG. 6B), correction is made to the first person's center-of-gravity position represented by the first coordinate system. For example, the correction unit 13 corrects the first person center of gravity position by displacing the second person center of gravity position represented by the second coordinate system in accordance with the relative displacement amount. In this case, the relative displacement amount is a first relative displacement amount that is a displacement amount in the horizontal direction of the bed 30 (see FIG. 1).

  Based on FIG. 6B, an example of the correction of the first person center of gravity position will be described. As shown in FIG. 6B, the center of gravity position BG of the bed 30 (shown by a solid line) where no person exists at the lowest lowered position Pdw is, for example, the coordinate in the first coordinate system of the bed 30 at the lowest lowered position Pdw ( x1, y). Similarly, the center-of-gravity position BG1 of the bed 30 (indicated by a virtual line) where there is no person at the highest rise position Pup is, for example, the coordinate (x1, y) in the first coordinate system of the bed 30 at the highest rise position Pup. ). The coordinates of the center of gravity position BG and the center of gravity position BG1 are the same in the first coordinate system regardless of the lowest position Pdw or the highest position Pup.

  Next, when the center of gravity position BG1 of the bed 30 (indicated by an imaginary line) at which the person does not exist at the highest rise position Pup is calculated based on the second reference point K2 of the second coordinate system, for example, In the coordinate system, it is represented by coordinates [X2, y]. The center-of-gravity position BG1 at the highest ascent position Pup is displaced by the first relative displacement amount Δxa in the horizontal direction when the bed 30 is raised between the coordinates in the first coordinate system and the coordinates in the second coordinate system.

The center of gravity position BG1 calculated with reference to the second reference point K2 of the second coordinate system is represented by the center of gravity position BG1 calculated with reference to the second reference point K2 of the second coordinate system. Is corrected by adding the first relative displacement amount Δxa to the X-axis coordinate [X2] (see equation (5)). The corrected gravity center position BG1 is represented by coordinates (X2 + Δxa, y) in the first coordinate system.

  A similar correction causes the second person's center-of-gravity position MG1 of the person existing on the bed 30 at the highest ascending position Pup calculated on the basis of the second reference point K2 of the second coordinate system to be generated along with ascending and descending. Based on the relative displacement of the first reference point K1 with respect to the reference point K2, the first person center of gravity position MG, which is the position of the center of gravity of the person represented in the first coordinate system, is corrected. For example, it is assumed that the second person center-of-gravity position MG1 is represented by coordinates [X3, y]. The second person center of gravity position MG1 is corrected by adding the first relative displacement amount (Δxa) to the X-axis coordinate [X3] of the calculated second person center of gravity position MG1, and the corrected first person center of gravity position MG1. MG is represented by coordinates (x3 + Δxa, y) in the first coordinate system. Thereby, the first person center-of-gravity position MG is corrected to an accurate position with respect to the first coordinate system of the bed 30.

  The first relative displacement amount calculation unit 15 illustrated in FIG. 5 calculates the horizontal displacement amount of the bed 30 (see FIG. 1) detected by the horizontal displacement amount detection unit 60 as the first relative displacement amount. . The first relative displacement amount calculation unit 15 acquires the detection signal output from the input unit 14. The first relative displacement amount calculation unit 15 calculates the first relative displacement amount according to the horizontal displacement amount of the detection signal. The first relative displacement amount calculation unit 15 outputs the calculated first relative displacement amount to the correction unit 13.

  The communication device 16 can perform two-way wireless communication with an input device (portable terminal) D having a display such as a mobile phone. As a result, the biological information detection device T (see FIG. 1) can output biological information including the human gravity center position to the input device D. Further, the biological information detection device T can input input information from the input device D and the like.

  Although not shown, the control device 10 includes a biological information detection unit. The biological information detection unit determines whether the person on the bed B1 is sleeping or awake based on the detected loads W1, W2, W3, W4 from the load sensors 5a, 5b, 5c, 5d, It detects biological information such as body movement during sleep, sleep depth, and heart rate.

  Based on FIG. 7, the human center-of-gravity position correction process executed by the control device 10 of the biological information detection apparatus T will be described. In this process, the control device 10 (see FIG. 5) first detects the detected loads W1, W2, W3, W4 (see FIG. 5) from the load sensors 5a, 5b, 5c, 5d (see FIG. 5) at predetermined time intervals. Reference) is acquired (S21). Next, the control device 10 calculates the second person center-of-gravity position based on the acquired detected loads W1, W2, W3, and W4 (S22).

  Then, the control apparatus 10 detects the amount of horizontal displacement accompanying the raising / lowering of the bed 30 (refer FIG. 1) by the horizontal direction displacement amount detection part 60 (S23). And the control apparatus 10 calculates the displacement amount to the horizontal direction of the bed 30 as a 1st relative displacement amount according to the displacement amount of the horizontal direction of the bed 30 (S24). Next, the control device 10 corrects the second person gravity center position calculated in the process of S22 to the first person gravity center position according to the calculated first relative displacement amount (S25).

  Further, the control device 10 outputs the corrected first person center-of-gravity position MG to the input device D via the communication device 16. When the first person center-of-gravity position MG is a position where the upper surface 32a of the bed 30 is biased, the control device 10 issues an alarm with the input device D via the communication device 16 (S26). Thereafter, the control device 10 ends the process.

  In the present embodiment, the control device 10 of the biological information detection device T calculates the relative displacement amount of the first reference point K1 with respect to the second reference point K2 that occurs as the bed 30 (see FIG. 1) moves up and down. The first relative displacement amount is a displacement amount of the bed 30 in the horizontal direction. Then, the control device 10 corrects the second person gravity center position MG1 represented by the second coordinate system to the first person gravity center position MG represented by the first coordinate system based on the first relative displacement amount. However, the present invention is not limited to this.

  For example, the relative displacement amount may be a second relative displacement amount calculated from a correlated displacement amount that has a correlation with the horizontal displacement amount of the bed 30 (see FIG. 1). In this case, it is desirable that the correlation displacement amount be a displacement amount at a height position of the bed 30 from the floor U as the bed 30 is moved up and down. The second relative displacement amount is a displacement amount calculated from the displacement amount of the height position from the floor U of the bed 30.

  FIG. 8 shows the first person center-of-gravity position expressed in the first coordinate system based on the detected relative displacement amount, for example, the second relative displacement amount calculated from the height position of the bed 30 (see FIG. 1). The control apparatus 10A of the biological information detection apparatus T of another configuration of the present embodiment for correcting the above is shown. The basic configuration of the control device 10A is substantially the same as that of the control device 10 described above, and the differences will be mainly described. In the drawings, the same members are denoted by the same reference numerals, and description thereof will be omitted.

  The control device 10A includes a correlated displacement amount detection unit 60a that detects a correlated displacement amount that has a correlation with the horizontal displacement amount of the bed 30 (see FIG. 1). The correlation displacement amount detection unit 60 a detects the height position of the bed 30. The correlation displacement amount detection unit 60a is provided, for example, on the lower surface of the front end of the bed 30 (see FIG. 1). The correlated displacement detection unit 60a detects the height H in the vertical direction between the bed 30 and the floor U. The correlation displacement amount detection unit 60a is, for example, a known optical distance sensor. The correlation displacement amount detection unit 60a is electrically connected to the input unit 14 of the control device 10 by wire or wirelessly.

The input unit 14 acquires the height position signal output from the correlation displacement amount detection unit 60a. The input unit 14 outputs the acquired height position signal as an input signal to the second relative displacement amount calculation unit 17.
The second relative displacement amount calculation unit 17 calculates the height position of the bed 30 (see FIG. 1) detected by the correlation displacement amount detection unit 60a as the second relative displacement amount. The second relative displacement amount calculation unit 17 acquires the detection signal output from the input unit 14. The second relative displacement amount calculation unit 17 calculates a second relative displacement amount according to the height position of the detection signal. The second relative displacement amount calculation unit 17 outputs the calculated second relative displacement amount to the correction unit 13.

  As shown in FIG. 9, in the first modification of the human center-of-gravity position correction process performed by the control device 10A (see FIG. 8), the control device 10A first acquires the detected loads W1, W2, W3, and W4 (S31). ). Next, the control device 10A calculates the second person center-of-gravity position (S32). The control device 10A detects the height position of the bed 30 (see FIG. 1) by the correlation displacement amount detection unit 60a (S33). Then, the control device 10A calculates the horizontal displacement amount of the bed 30 as the second relative displacement amount according to the height position of the bed 30 (S34). In this case, the second relative displacement amount is calculated based on a map stored in advance in the control device 10A, for example, a map indicating the second relative displacement amount according to the height position of the bed 30. Next, 10 A of control apparatuses correct | amend the 2nd person gravity center position calculated by the process of S32 to a 1st person gravity center position according to the calculated 2nd relative displacement amount (S35). Thereafter, when the corrected first person gravity center position is a biased position of the upper surface 32a of the bed 30 (see FIG. 1), the control device 10A issues an alarm at the input device D via the communication device 16 ( S36). Thereafter, the control device 10A ends the process.

  The control device 10A is configured to detect the distance between the lower surface of the bed 30 and the floor U by the correlation displacement amount detection unit 60a to detect the height position of the bed 30, but is not limited thereto. For example, the control device 10A may be configured to detect the distance between the lower surface of the bed 30 and the left side frame 21a of the base 20 by using a correlation displacement amount detection unit 60b indicated by a virtual line in FIG.

  Moreover, 10 A of control apparatuses are 2nd according to the movement amount of the expansion-contraction rod 454 of the actuator 45 (refer FIG. 3) of the raising / lowering apparatus 40 as a correlation displacement amount which has a correlation with the displacement amount to the horizontal direction of the bed 30. The relative displacement amount may be calculated. In this case, it is desirable to replace the amount of movement of the telescopic rod 454 of the actuator 45 with the motor rotation speed of the electric motor 452 detected by the correlated displacement detection unit 60c such as an encoder attached to the electric motor 452. 8, when the input unit 14 acquires the detection signal of the motor rotation number detected by the correlation displacement amount detection unit 60c, the input unit 14 converts the acquired detection signal to the second relative displacement. It outputs to the quantity calculation part 17. Thereby, the second relative displacement amount calculation unit 17 calculates the second relative displacement amount according to the acquired motor rotation speed.

Further, as shown in FIG. 10, for example, as illustrated in FIG. 10, the control device 10 </ b> A determines the rotation angle of the intermediate arm 42 of the left front lifting mechanism 40 a of the lifting device 40 as a correlated displacement amount correlated with the horizontal displacement amount of the bed 30. A configuration may be used in which the second relative displacement amount is calculated according to θ1 and the rotation angle θ2. For example, the connecting portion 421 between the lower arm 41 and the intermediate arm 42 of the left front lifting mechanism 40a is provided with a correlated displacement amount detection unit 60d such as an encoder. The correlation displacement amount detection unit 60d detects the rotation angle of the intermediate arm 42 as the bed 30 is moved up and down. 8A, when the input unit 14 acquires the detection signals of the rotation angle θ1 and the rotation angle θ2 detected by the correlation displacement amount detection unit 60d, the input unit 14 detects the acquired detection. The signal is output to the second relative displacement amount calculation unit 17. Thereby, the second relative displacement amount calculation unit 17 calculates the second relative displacement amount that is the height H of the bed 30 in accordance with the acquired rotation angle θ1 and rotation angle θ2. The height H of the bed 30 is calculated from the equation (8) derived from the equations (6) and (7).

<Effect of the first embodiment>
As is apparent from the present embodiment, the biological information detection device T (FIG. 1) has a base 20 (FIG. 1) and an upper surface 32a (FIG. 1) on which the person can exist. A bed 30 having a first reference point K1 (FIG. 6B) serving as a reference of a first coordinate system that defines the position of the center of gravity of the person existing on the upper surface 32a, and a base 20 and a bed 30 (FIG. 1). The bed 30 is moved up and down with respect to the base 20 so that the load applied to the bed 30 can be transmitted to the base 20, and the bed 30 without a person on the upper surface 32a moves up and down. In this case, the present invention is applied to a bed B1 (FIG. 1) including an elevating device 40 (FIG. 1) that raises and lowers the bed while the load center, which is the center of the distribution of the load applied to the base 20, is displaced in the horizontal direction. A biological information detection device T, which is provided at a plurality of predetermined locations on the base 20 and each predetermined A plurality of load sensors 5a, 5b, 5c, and 5d (FIG. 2) for detecting a load applied to the place, and a plurality of detected loads that are respective loads detected by the plurality of load sensors 5a, 5b, 5c, and 5d, respectively. From W1, W2, W3, and W4 (FIG. 2), the position of the center of gravity of the person existing on the upper surface 32a of the bed 30 is determined based on the second reference point K2 (FIG. 6B) related to the base 20. The second person centroid position represented by the second coordinate system calculated by the second person centroid position calculator 12 (FIG. 5) and the second person centroid position calculator 12 calculated in the second coordinate system MG1 (FIG. 6B) is the human center-of-gravity position represented in the first coordinate system based on the relative displacement amount of the first reference point K1 with respect to the second reference point K2 generated as the elevator device 40 is raised and lowered. Correction unit 13 (FIG. 5) for correcting to the first person center-of-gravity position MG (FIG. 6B). It has a, and.

  According to this, the second person center-of-gravity position calculation unit 12 calculates the bed from the plurality of detected loads W1, W2, W3, and W4 that are the respective loads detected by the plurality of load sensors 5a, 5b, 5c, and 5d. The human center of gravity position, which is the center of gravity position of the person existing on the upper surface 32a of 30, is calculated in the second coordinate system with the second reference point K2 related to the base as a reference. The correction unit 13 applies the second person center of gravity position MG1 represented by the second coordinate system calculated by the second person center of gravity position calculation unit 12 to the second reference point K2 that is generated as the elevator device 40 moves up and down. Based on the relative displacement amount of the first reference point K1, the first person center of gravity position MG, which is the person center of gravity position represented in the first coordinate system, is corrected. As described above, the first person centroid position MG1 represented by the second coordinate system calculated by the second person centroid position calculation unit 12 is the first person centroid position represented by the first coordinate system. It is possible to correct the center of gravity position MG. Therefore, even if the center of load applied to the base 20 is displaced in the horizontal direction as the bed 30 is moved up and down, the biological information detection that can accurately calculate the actual center-of-gravity position of the person existing on the bed 30 An apparatus can be provided.

  The elevating device 40 is provided between the base 20 and the bed 30, and moves up and down while displacing the bed 30 in the horizontal direction with respect to the base 20 so that a load applied to the bed 30 can be transmitted to the base 20. And when the bed 30 where no person is present on the upper surface 32a is moved up and down, the load center is moved up and down while being displaced in the horizontal direction, and the relative displacement amount is the amount of displacement of the bed 30 in the horizontal direction. The first relative displacement amount or the second relative displacement amount calculated from the correlated displacement amount correlated with the horizontal displacement amount of the bed 30.

  According to this, as the relative displacement amount of the first reference point K1 with respect to the second reference point K2 generated along with the lifting and lowering of the lifting device 40, the first relative displacement amount that is the displacement amount of the bed 30 in the horizontal direction, Alternatively, based on the second relative displacement amount calculated from the correlated displacement amount that correlates with the horizontal displacement amount of the bed 30, the position of the center of gravity of the person represented by the first coordinate system is efficiently and accurately determined. Can be corrected.

  When the relative displacement amount is the first relative displacement amount, the biological information detection device T includes a horizontal displacement amount detection unit 60 (FIG. 1) that detects the displacement amount of the bed 30 in the horizontal direction, and the horizontal displacement. A first relative displacement amount calculation unit 15 (FIG. 5) that calculates the displacement amount in the horizontal direction of the bed 30 detected by the amount detection unit 60 as the first relative displacement amount is further provided.

  According to this, the horizontal displacement amount detection unit 60 detects the displacement amount of the bed 30 in the horizontal direction. The first relative displacement amount calculation unit 15 calculates the detected displacement amount of the bed 30 in the horizontal direction as the first relative displacement amount. Thus, the first relative displacement amount can be efficiently calculated from the displacement amount in the horizontal direction of the bed 30 detected by the horizontal direction displacement amount detection unit 60.

  When the relative displacement amount is the second relative displacement amount, the biological information detection apparatus T includes correlated displacement amount detection units 60a, 60b, 60c, and 60d (FIGS. 1, 3, and 10) that detect the correlated displacement amount. And a second relative displacement amount calculation unit 17 (FIG. 8) that calculates a second relative displacement amount from the correlation displacement amounts detected by the correlation displacement amount detection units 60a, 60b, 60c, and 60d.

  According to this, the correlation displacement amount detection units 60a, 60b, 60c, and 60d detect the correlation displacement amount. The second relative displacement amount calculation unit 17 calculates a second relative displacement amount from the detected correlation displacement amount. Thus, the second relative displacement amount can be efficiently calculated from the correlated displacement amounts detected by the correlated displacement amount detection units 60a, 60b, 60c, and 60d.

<Second embodiment>
A second embodiment to which the present invention is applied will be described. As shown in FIG. 11, in the present embodiment, the bed 30 moves up and down without being displaced in the horizontal direction with respect to the base 20, and the load distribution applied to the base 20 as the bed 30 moves up and down. The biological information detection device T of the present invention is used for the bed B2 in which the load center which is the center of the center is displaced in the horizontal direction. The basic configuration of the present embodiment is almost the same as that of the first embodiment, and differences will be mainly described. In the figure, the same members are denoted by the same reference numerals.

  As shown in FIGS. 11 and 12, the lifting device 40 </ b> A of the bed B <b> 2 includes a left lifting mechanism 40 e and a right lifting mechanism 40 f on the left and right sides of the base 20. The left elevating mechanism 40e is provided on the left side frame 21a of the base 20. The right elevating mechanism 40f is provided on the right frame 21b of the base 20. The left elevating mechanism 40e and the right elevating mechanism 40f have a bilaterally symmetric structure between the left side and the right side of the base 20 except that the installation positions are different. The configuration of the left elevating mechanism 40e and the right elevating mechanism 40f will be described centering on the left elevating mechanism 40e of the base 20.

  The left elevating mechanism 40e includes a first arm 401, a second arm 402, a lower fixed arm 403, an upper slide portion 404, an upper fixed arm 405, and a lower slide portion 406. The left elevating mechanism 40e and the right elevating mechanism 40f include a first connecting rod 407 and a second connecting rod 409 that connect the left elevating mechanism 40e and the right elevating mechanism 40f.

  The first arm 401 and the second arm 402 intersect with each other in an X shape at an intermediate position in the longitudinal direction, and are connected to each other by a first connecting rod 407 so as to be relatively rotatable. The first connecting rod 407 is a rod-shaped member that extends along the left-right direction of the base 20. The left end portion of the first connecting rod 407 rotatably connects the first arm 401 and the second arm 402 of the left lifting mechanism 40e. On the other hand, the right end portion of the first connecting rod 407 connects the first arm 401 and the second arm 402 of the right elevating mechanism 40f so as to be rotatable. Thus, the 1st connection rod 407 is the structure which connects the connection part of the 1st arm 401 and the 2nd arm 402 of the left raising / lowering mechanism 40e and the right raising / lowering mechanism 40f.

  The lower end of the lower fixed arm 403 is fixed to the front portion of the left side frame 21 a of the base 20, and the lower fixed arm 403 extends upward from the base 20. The front end of the first arm 401 is rotatably connected to the lower fixed arm 403.

  The upper end of the upper slide portion 404 is provided to be slidable in the front-rear direction along the rear lower surface of the left frame 31 a of the bed 30. The upper slide portion 404 is extended downward from the bed 30. The upper slide portion 404 is rotatably connected to the rear end of the first arm 401.

  The second connecting rod 409 is a member that extends along the left-right direction of the base 20. The left end portion of the second connecting rod 409 is connected to the rear end of the first arm 401 of the left elevating mechanism 40e. On the other hand, the right end portion of the second connecting rod 409 is connected to the rear end of the first arm 401 of the right elevating mechanism 40f. Thus, the 2nd connecting rod 409 is the structure which connects the rear end of the 1st arm 401 of the left raising / lowering mechanism 40e and the right raising / lowering mechanism 40f.

  The upper end of the upper fixed arm 405 is fixed to the rear portion of the left frame 31 a of the bed 30, and the upper fixed arm 405 extends downward from the bed 30. The upper fixed arm 405 is rotatably connected to the front end of the second arm 402.

  The lower end of the lower slide portion 406 is provided to be slidable in the front-rear direction along the rear portion of the left side frame 21a of the base 20. The lower slide portion 406 extends upward from the base 20. The lower slide part 406 is rotatably connected to the rear end of the second arm 402.

  The lifting device 40A includes an actuator 45 on the lower surface of the center of the bed 30 as a driving device. The base end 455 of the actuator 45 is rotatably connected to the approximate center of the lower surface of the horizontal frame 31c. In the actuator 45, the distal end 456 of the telescopic rod 454 is connected to the rear ends of the left and right first arms 401 via a second connecting rod 409 that connects the rear ends of the left and right first arms 401.

  The raising / lowering of the bed 30 by the raising / lowering apparatus 40A is demonstrated. The bed 30 shown by the solid line in FIG. 11 shows a state where the bed 30 is lowered to the lowest lowered position Pdw. In this state, in the lifting device 40A, the front end of the first arm 401 and the front end of the second arm 402 are close to each other in the vertical direction, and the rear end of the first arm 401 and the rear end of the second arm 402 are in the vertical direction. Take a close posture. The upper slide portion 404 at the rear end of the first arm 401 is located at the rear end of the slidable range. Similarly, the lower slide portion 406 at the rear end of the second arm 402 is located at the rear end of the slidable range. The actuator 45 is extended by the movement of the nut portion 451b accompanying the rotation of the ball screw 451a.

The elevating device 40A moves the upper slide portion 404 at the rear end of the first arm 401 forward by contracting the actuator 45 by the movement of the nut portion 451b accompanying the rotation of the ball screw 451a. As a result, the first arm 401 rotates upward with the connecting portion at the front end as the rotation center. As a result, the connecting portion between the first arm 401 and the second arm 402 moves upward and forward. By moving the connecting portion between the first arm 401 and the second arm 402, the second arm 402 moves the lower slide portion 406 at the rear end forward, and rotates upward with the connecting portion at the rear end as a rotation center. Move. Therefore, the bed 30 is raised while maintaining the horizontal posture without moving in the front-rear direction by the rotation of the first arm 401 and the second arm 402.
As described above, the lifting device 40A is provided between the base 20 and the bed 30 and the bed 30 is horizontally arranged with respect to the base 20 so that the load applied to the bed 30 can be transmitted to the base 20. Raise and lower without displacement.

  The rising bed 30 is not displaced in the horizontal direction, but the lower slide portion 406 at the rear end of the second arm 402 of the lifting device 40A moves in the horizontal direction. Accordingly, the upper slide portion 404 at the rear end of the first arm 401 moves forward in the horizontal direction. When the bed 30 is raised, the lower slide part 406 at the rear end of the second arm 402 and the upper slide part 404 at the rear end of the first arm 401 of the lifting device 40A move forward in the horizontal direction. The load of the bed 30 applied to the front leg portions 23a and 23b becomes larger than before the rise. Therefore, the load center (also referred to as the load center of the base 20), which is the distribution center of the load applied to the base 20, is displaced forward. In the bed B2, the load center of the base 20 moves forward as the bed 30 rises. If the amount of movement of the lower slide portion 406 at the rear end of the second arm 402 and the upper slide portion 404 at the rear end of the first arm 401 in the lifting device 40A in the horizontal direction is large, move forward to the load center of the base 20. The amount of displacement increases.

As illustrated in FIG. 13, the control device 10 </ b> B of the biological information detection device T according to the present embodiment includes a vertical direction displacement amount detection unit 60 e that detects the amount of displacement of the bed 30 in the vertical direction. In addition, the control device 10B includes a third relative displacement amount calculation unit 18 that calculates the displacement amount in the vertical direction of the bed 30 detected by the vertical direction displacement amount detection unit 60e as a third relative displacement amount.
The control device 10B determines the third relative displacement calculated from the vertical displacement of the bed 30 as the relative displacement of the first reference point K1 with respect to the second reference point K2 that occurs as the bed 30 moves up and down. Amount.

  The vertical displacement amount detection unit 60 e detects the height position of the bed 30. The vertical displacement amount detection unit 60e is provided, for example, on the lower surface of the rear end of the bed 30 (see FIG. 11). The vertical direction displacement amount detection unit 60e detects the height H in the vertical direction between the bed 30 and the floor U. The correlation displacement amount detection unit 60a is, for example, a known optical distance sensor. The correlation displacement amount detection unit 60a is electrically connected to the input unit 14 of the control device 10 by wire or wirelessly.

  The third relative displacement amount calculation unit 18 calculates the height position of the bed 30 (see FIG. 11) detected by the vertical displacement amount detection unit 60e as the third relative displacement amount. The third relative displacement amount calculation unit 18 acquires the detection signal output from the input unit 14. The third relative displacement amount calculation unit 18 calculates a third relative displacement amount according to the height position of the detection signal. The third relative displacement amount calculation unit 18 outputs the calculated third relative displacement amount to the correction unit 13.

  As shown in FIG. 14, in the second modification of the human center-of-gravity position correction process executed by the control device 10B (see FIG. 13), the control device 10B first acquires detected loads W1, W2, W3, and W4 (S41). ). Next, the control device 10B calculates the second person's center of gravity position (S42). The control device 10B detects the height position of the bed 30 (see FIG. 11) by the vertical displacement amount detection unit 60e (S43). Then, the control device 10B calculates the third relative displacement amount according to the height position of the bed 30 (S44). In this case, the third relative displacement amount is calculated based on a map indicating the third relative displacement amount corresponding to the height position of the bed 30 stored in the control device 10B in advance. Next, the control device 10B corrects the second person gravity center position calculated in the process of S42 to the first person gravity center position according to the calculated third relative displacement amount (S45).

  Based on FIG. 15, an example of the correction of the first person center of gravity position will be described. As shown in FIG. 15, the center of gravity position BG of the bed 30 (shown by a solid line) at which the person does not exist at the lowest lowered position Pdw is, for example, expressed in the first coordinate system of the bed 30 at the lowest lowered position Pdw. x1, y). On the other hand, when the center of gravity position BG1 of the bed 30 (indicated by a virtual line) at which the person does not exist at the highest rise position Pup is calculated based on the second reference point K2 of the second coordinate system, for example, In the system, it is represented by coordinates [X2, y]. The center of gravity position BG1 in the second coordinate system at the highest ascent position Pup is a second reference point that accompanies the rise of the bed 30 relative to the coordinates of the center of gravity position BG in the first coordinate system of the bed 30 at the lowest position Pdw. A displacement of the third relative displacement amount Δxb in the horizontal direction is generated by the displacement of K2 to the second reference point K21.

The center of gravity position BG1 calculated with reference to the second reference point K2 of the second coordinate system is represented by the center of gravity position BG1 calculated with reference to the second reference point K2 of the second coordinate system. Is corrected by adding the third relative displacement amount Δxb to the X-axis coordinate [X2] (see equation (9)). The corrected gravity center position BG1 is represented by coordinates (x2 + Δxb, y) in the first coordinate system.

  By a similar correction, the first relative to the second reference point K21 is determined from the second person center of gravity position MG1 of the person on the bed 30 at the highest ascending position Pup calculated with reference to the second reference point K21 of the second coordinate system. Based on the relative displacement amount of the reference point K1, it is corrected to the first person center of gravity position MG, which is the person center of gravity position represented in the first coordinate system. For example, it is assumed that the second person center-of-gravity position MG1 is represented by coordinates [X3, y]. The second person center of gravity position MG1 is corrected by adding the third relative displacement (Δxb) to the X-axis coordinate [X3] of the calculated second person center of gravity position MG1. MG is represented by coordinates (x3 + Δxb, y) in the first coordinate system. Thereby, the first person center-of-gravity position MG is corrected to an accurate position with respect to the first coordinate system of the bed 30.

  As shown in FIG. 14, after that, the control device 10 </ b> B alerts the input device D via the communication device 16 when the corrected first person gravity center position is a biased position of the upper surface 32 a of the bed 30. (S46). Thereafter, the control device 10B ends the process.

<Effect of the second embodiment>
According to the control device 10B of the biological information detection device T of the present embodiment, the same operational effects as those of the first embodiment can be obtained. In addition, the lifting device 40A (FIG. 13) of the present embodiment is provided between the base 20 (FIG. 11) and the bed 30 (FIG. 11), and the load applied to the bed 30 is applied to the base 20. When the bed 30 is moved up and down without being displaced horizontally with respect to the base 20 so as to be able to be transmitted, and the bed 30 without a person on the upper surface 32a (FIG. 11) moves up and down, the load center is displaced in the horizontal direction. While the bed 30 is moved up and down, the relative displacement amount is a third relative displacement amount calculated from the amount of displacement of the bed in the vertical direction.

  According to this, as the relative displacement amount of the first reference point K1 with respect to the second reference point K2 generated along with the lifting and lowering of the lifting device 40A, the third relative displacement amount that is the displacement amount of the bed 30 in the horizontal direction is used. Based on this, the position of the center of gravity of the person represented by the first coordinate system can be corrected efficiently and accurately.

  The biological information detection device T includes a vertical displacement detection unit 60e (FIG. 13) that detects the vertical displacement of the bed 30 and the vertical direction of the bed 30 detected by the vertical displacement detection unit 60e. And a third relative displacement amount calculation unit 18 that calculates the displacement amount to the third relative displacement amount.

  According to this, the up-down direction displacement amount detection unit 60e detects the amount of displacement of the bed 30 in the up-down direction. The third relative displacement amount calculation unit 18 calculates the detected vertical displacement amount of the bed 30 as the third relative displacement amount. As described above, the third relative displacement amount can be efficiently calculated from the displacement amount in the vertical direction of the bed 30 detected by the vertical displacement amount detection unit 60e.

It should be noted that the present invention is not limited to the embodiments described above, and can of course be implemented in various ways without departing from the gist of the present invention. For example, in the control devices 10A and 10B of the biological information detection apparatus T including the second relative displacement amount calculation unit 17 or the third relative displacement amount calculation unit 18, a control signal for controlling the raising and lowering of the bed is acquired and the control signal is used as the control signal. Based on this, the second relative displacement amount or the third relative displacement amount may be calculated.
The biological information detection apparatus T of the present invention is not limited to a bed in which the load center of the bed base moves along the back-and-forth direction of the bed, and the load center of the base is along the left-right direction of the bed. It may be applied to moving beds.

  Next, a mattress device 70 with an automatic pillow generation function that is installed on the bed 30 of the beds B1 and B2 and can be optimally used for sleeping of a person will be described with reference to FIGS. The mattress device 70 detects the pressure applied to the mattress 71 of the person M existing on the mattress 71 and determines the position of the human body. The mattress device 70 is configured to optimize the contours of the pillow and mattress by inflating or deflating the airbag 72 built in the mattress 71. In this case, the mattress device 70 does not distinguish between a pillow part and other parts. Then, the mattress device 70 estimates the position of the head M1 and the direction of the body from the detected pressure applied to the mattress 71 of the person M, and the mattress 71 rises or sinks according to the position of the person M sleeping. By doing so, the pillow part 71a is generated.

  As shown in FIGS. 16 and 18, the mattress 71 includes a plurality of airbags 72 that can be inflated and deflated by air intake and exhaust. Each airbag 72 is formed of a resin fibrous member on a cloth having non-stretchability, flexibility, and low air permeability. Each airbag 72 is formed in a bag shape that is vertically long in the height direction with respect to the dimension in the front-rear direction and the dimension in the left-right direction when inflated. For example, each airbag 72 has a front / rear / left / right dimension of about 10 cm, and a height dimension when inflated of about 20 cm. The airbags 72 are arranged in a lattice shape along the longitudinal direction and the width direction of the mattress 71. Adjacent airbags 72 are arranged at an interval so as not to interfere with each other during inflation and prevent the other side from being inflated.

  Each airbag 72 is connected to an air pump 80 via an air supply / exhaust pipe 81. Each air supply / exhaust pipe 81 connected to each airbag 72 is provided with a valve device V that shuts off the air flow to the airbag 72. Each valve device V includes a ventilation shutoff valve 82 that shuts off air flow between the airbag 72 and the air pump 80. Each valve device V includes a pressure sensor 83 that detects the pressure in the airbag 72. Further, each valve device V includes an exhaust cutoff valve 84 that exhausts the air in the airbag 72.

  The ventilation cutoff valve 82, the pressure sensor 83, and the exhaust cutoff valve 84 are electrically connected to the mattress control device 90. The ventilation shutoff valve 82 and the exhaust shutoff valve 84 are shut off from the air flow under the control of the mattress control device 90. The pressure sensor 83 outputs a pressure signal indicating the detected pressure of each airbag 72 toward the mattress control device 90.

  The mattress 71 includes a sheet-like body pressure sensor 73 that detects the pressure of the person M applied to the mattress 71. The body pressure sensor 73 is disposed on the upper side of each airbag 72 over substantially the entire range where each airbag 72 is disposed. The body pressure sensor 73 is electrically connected to the mattress control device 90. The body pressure sensor 73 outputs the detected pressure signal toward the mattress control device 90. The mattress control device 90 includes a position analysis unit 91 that analyzes the position of the person M on the mattress 71. The mattress control device 90 acquires a body pressure signal detected by the body pressure sensor 73 in the position analysis unit 91.

  When the position analysis unit 91 analyzes the position of the head M1 of the person M on the mattress 71, the mattress control device 90 controls the valve devices V of the plurality of airbags 72 corresponding to the positions of the head M1. The plurality of airbags 72 are inflated. Thereby, in the mattress 71, the surface of the portion where the airbag 72 is inflated is raised to form the pillow portion 71a.

  According to the mattress device 70, since the pillow portion 71a can be formed at an arbitrary position on the mattress 71, the mattress device 70 can be used in a wide age group regardless of the physique of the person M.

T: biological information detection device, 12: second person center of gravity position calculation unit, 13: correction unit, 15: first relative displacement amount calculation unit, 17: second relative displacement amount calculation unit, 18: third relative displacement amount calculation Part, 20: base, 30: bed, 32a: upper surface, 40, 40A: lifting device, 5a, 5b, 5c, 5d: load sensor, B1, B2: bed, K1: first reference point, K2, K21 : Second reference point

Claims (6)

The base,
A bed that is disposed above the base and has a top surface on which a person can exist, and a first reference point serving as a reference of a first coordinate system that defines the position of the center of gravity of the person existing on the top surface; ,
The bed is provided between the base and the bed, the bed is lifted with respect to the base so that a load applied to the bed can be transmitted to the base, and the person is present on the top surface Biological information applied to a bed comprising: a lifting device that lifts and lowers the bed while the center of load that is the center of the distribution of the load applied to the base is displaced in the horizontal direction when the bed is moved up and down A detection device,
A plurality of load sensors provided at a plurality of predetermined locations of the base and for detecting a load applied to each of the predetermined locations;
From the plurality of detected loads that are the respective loads respectively detected by the plurality of load sensors, a human center of gravity position that is the center of gravity of the person existing on the upper surface of the bed is determined as a second reference related to the base. A second person center-of-gravity position calculating unit to calculate in a second coordinate system based on the point;
The first reference point with respect to the second reference point, which is generated by raising and lowering the lifting device, the second person center of gravity position represented by the second coordinate system calculated by the second person center of gravity position calculating unit Based on the relative displacement amount, a correction unit that corrects the first person center of gravity position, which is the person center of gravity position represented in the first coordinate system,
A biological information detection apparatus comprising: The lifting device is provided between the base and the bed, and moves up and down while displacing the bed in a horizontal direction with respect to the base so that a load applied to the bed can be transmitted to the base. And when the bed without the person on the upper surface moves up and down, the load center is configured to move up and down while being displaced in the horizontal direction,
The relative displacement amount is calculated from a first relative displacement amount that is a displacement amount of the bed in the horizontal direction or a correlation displacement amount that is correlated with the displacement amount of the bed in the horizontal direction. 2. The biological information detection device according to claim 1, wherein the biological information detection device is a relative displacement amount.   When the relative displacement amount is the first relative displacement amount, the biological information detection device includes a horizontal displacement amount detection unit that detects a horizontal displacement amount of the bed, and the horizontal displacement amount detection. The biological information detection device according to claim 2, further comprising: a first relative displacement amount calculation unit configured to calculate, as the first relative displacement amount, a horizontal displacement amount of the bed that is detected by the unit.   In the case where the relative displacement amount is the second relative displacement amount, the biological information detection apparatus includes a correlated displacement amount detection unit that detects the correlated displacement amount, and the correlated displacement detected by the correlated displacement amount detection unit. The biological information detection apparatus according to claim 2, further comprising: a second relative displacement amount calculation unit that calculates the second relative displacement amount from the amount. The elevating device is provided between the base and the bed, and lifts and lowers the bed without horizontally displacing the bed with respect to the base so that a load applied to the bed can be transmitted to the base. And when the bed without the person on the upper surface moves up and down, the load center is configured to move up and down while being displaced in the horizontal direction,
The biological information detection apparatus according to claim 1, wherein the relative displacement amount is a third relative displacement amount calculated from a displacement amount in the vertical direction of the bed.   The biological information detection apparatus includes a vertical displacement amount detection unit that detects a vertical displacement amount of the bed, and a vertical displacement amount of the bed detected by the vertical displacement amount detection unit. The biological information detection apparatus according to claim 5, further comprising a third relative displacement amount calculation unit that calculates the third relative displacement amount.

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