Bed Apparatus Provided With Bed-Departure Prediction and Detection System

• US 20090260158A1
• Filed: 01/19/2007
• Published: 10/22/2009
• Est. Priority Date: 01/20/2006
• Status: Active Grant

• Current Assignee: Paramount Bed Company Limited (Paramount Bed Holdings Company Limited)
• Original Assignee: Paramount Bed Company Limited (Paramount Bed Holdings Company Limited)
• Inventors: Morimura, Hisao, Kazuno, Hiroki
• Granted Patent: US 8,381,336 B2
• Time in Patent Office: Days
• US Class Current: 5/600
• CPC Class Codes: A61B 2562/046 in a matrix array
• CPC Class Codes: A61B 5/1115 Monitoring leaving of a patient support, e.g. a bed or a wheelchair
• CPC Class Codes: A61B 5/1117 Fall detection
• CPC Class Codes: A61B 5/6891 Furniture
• CPC Class Codes: A61G 7/0527 Weighing devices
• CPC Class Codes: G01G 19/445 in a horizontal position
• CPC Class Codes: G08B 21/0461 integrated or attached to an item closely associated with the person but not worn by the person, e.g. chair, walking stick, bed sensor
• CPC Class Codes: G08B 21/22 responsive to presence or absence of persons

Abstract

A load measuring unit detects the load of a bed section and generates a load signal. A body weight computing unit computes the body weight of a user positioned on the bed section on the basis of the load signal. A first determination unit determines whether the body weight is equal to or less than a prescribed threshold. A center-of-gravity position computing unit computes a center-of-gravity position of the user on the basis of the load signal. A second determination unit determines whether the center-of-gravity position is in a monitored area of the bed section. The state of the user is detected to away from the bed when the first determination unit has determined that the body weight is equal to or less than a prescribed threshold, and the second determination unit has determined that the center-of-gravity position is within the monitored area.

Claims

1. A bed apparatus comprising:

a load measuring unit for detecting the load of a bed section and generating a load signal;

a body weight computing unit for computing the body weight of a user positioned on the bed section on the basis of said load signal;

a first determination unit for determining whether said body weight is equal to or less than a prescribed threshold;

a center-of-gravity position computing unit for computing a center-of-gravity position of said user on the basis of said load signal; and

a second determination unit for determining whether said center-of-gravity position is in a monitored area of the bed section, wherein

the state of said user is detected when said first determination unit has determined that said body weight is equal to or less than a prescribed threshold, and said second determination unit has determined that said center-of-gravity position is within said monitored area.

2. The bed apparatus according to claim 1, further comprising a body weight threshold setting means for setting the threshold of said body weight, and a center-of-gravity position monitored area setting unit for setting said monitored area of said center-of-gravity position.

3. The bed apparatus according to claim 1, further comprising an alarm unit for generating an alarm when the state of said user has been detected.

4. The bed apparatus according to claim 1, wherein said monitored area is comprises a sitting position at the edge of the bed section, and the state of said user is comprises an edge sitting position.

5. The bed apparatus according to claim 1, further comprising a bed height storage unit for storing a bed section height reference value;

and a bed height determination unit for determining whether the current bed section height is greater than the bed section height reference value, wherein

the state of said user is detected solely by the determination result of said second determination unit regardless of the determination result of said first determination unit when said bed height determination unit has determined that the current bed section height is greater than the bed section height reference value.

6. The bed apparatus according to claim 1, further comprising a user body information input unit for inputting body information of the user, and a center-of-gravity position monitored area setting unit for setting said optimal center-of-gravity position monitored area, based on the inputted user body information.

7. The bed apparatus according to claim 1, further comprising a center-of-gravity position monitored area setting unit for setting said optimal center-of-gravity position monitored area, based on said center-of-gravity position of the user computed by said center-of-gravity position computing unit.

20. The bed apparatus according to claim 1, further comprising a body weight threshold setting unit for setting the optimal body weight threshold, based on the computed value of the body weight of said user.

21. The bed apparatus according to claim 20, further comprising an alarm unit for generating an alarm in accordance with a determination result that corresponds to the body weight threshold set by said body weight threshold setting unit.

22. The bed apparatus according to claim 1, further comprising a user health condition information input unit for inputting health condition information of a user, and an alarm setting unit for setting the optimal alarm unit, based on the inputted user health condition information.

23. The bed apparatus according to claim 22, further comprising a related-threshold setting unit that is capable of setting a threshold related to the alarm unit selected by said alarm setting unit, based on the health condition information of said user and the body information of said user.

8. A bed apparatus comprising:

a load measuring unit for detecting the load of a bed section and generating a load signal;

a body weight computing unit for computing the body weight of a user positioned on the bed section on the basis of said load signal;

a first determination unit for determining whether said body weight is equal to or less than a prescribed threshold;

a center-of-gravity position computing unit for computing a center-of-gravity position of said user on the basis of said load signal;

a center-of-gravity movement distance computing unit for computing the movement distance of a center-of-gravity position from the result of computing said center-of-gravity position; and

a second determination unit for determining whether the movement distance of said center-of-gravity position has exceeded a second threshold, wherein

the state of said user is detected when said second determination unit has determined that the movement distance of said center-of-gravity position has exceed said second threshold, and said first determination unit has determined that said body weight is equal to or less than said first threshold.

9. The bed apparatus according to claim 8, wherein the state of said user is detected when said first determination unit has furthermore determined whether said body weight is within a prescribed range, said second determination unit has determined that the movement distance of said center-of-gravity position has exceeded said second threshold, and said first determination unit has determined that said body weight is equal to or less than said first threshold and is within a prescribed range.

10. The bed apparatus according to claim 8, further comprising a body weight threshold setting unit for setting said first threshold, center-of-gravity position movement distance threshold setting unit for setting said second threshold of said center-of-gravity position, body weight range setting unit for setting a prescribed range of said body weight, and a center-of-gravity movement distance time difference setting unit for setting the time difference between two time instances that are used to compute the movement distance of said center-of-gravity position.

11. The bed apparatus according to claim 8, further comprising an alarm unit for generating an alarm when the state of said user has been detected.

12. The bed apparatus according to claim 8, wherein the threshold of the movement distance of said center-of-gravity position is set based on the movement distance when said user has sat up, and said user is in a sitting-up state.

13. A bed apparatus comprising

a load measuring unit for detecting the load of a bed section and generating a load signal;

a body weight computing unit for computing the body weight of a user positioned on the bed section on the basis of said load signal;

an abnormality detection unit for determining that said body weight in not within a prescribed range and detecting an abnormality; and

a body weight monitoring unit for monitoring the time said body weight has not been within the prescribed range, wherein

a weight abnormality is detected when said body weight monitoring unit has detected that the state in which said body weight is not within the prescribed range has continued for a prescribed length of time.

14. The bed apparatus according to claim 13, further comprising a body weight range setting unit for setting a prescribed range of said body weight, and a body weight-monitoring time setting unit for setting the time for monitoring said body weight computing value.

15. The bed apparatus according to claim 13, further comprising an alarm unit for generating an alarm in accordance with said weight abnormality detection.

16. A bed apparatus comprising:

a load measuring unit for detecting the load of a bed section and generating a load signal;

a body weight computing unit for computing the body weight of a user positioned on the bed section on the basis of said load signal;

a first determination unit for determining whether said body weight is equal to or greater than a prescribed threshold;

a center-of-gravity position computing unit for computing a center-of-gravity position of said user on the basis of said load signal;

a second determination unit for determining whether said center-of-gravity position is in a monitored area of the bed section; and

a body weight center-of-gravity position monitoring unit for monitoring the time in which said body weight is equal to or greater than a prescribed threshold and in which said center-of-gravity position is in said monitored area, wherein

the state of said user is detected when said body weight center-of-gravity position monitoring unit has detected that said body weight is equal to or greater than a prescribed threshold and that a state in which said center-of-gravity position is within said monitored area has continued for a prescribed length of time.

17. The bed apparatus according to claim 16, further comprising a body weight threshold setting unit for setting the threshold of said body weight, a center-of-gravity position monitored area setting unit for setting said monitored area of said center-of-gravity position, and a body weight center-of-gravity position monitoring time setting unit for setting the body weight center-of-gravity position monitoring time in which said body weight is equal to or greater than a prescribed threshold and in which said center-of-gravity position is in said monitored area.

18. The bed apparatus according to claim 16, further comprising an alarm unit for generating an alarm when the state of said user has been detected.

19. The bed apparatus according to claim 16, wherein said monitored area is in an unnatural position for the center-of-gravity of said user to be on the bed section.