Information
-
Patent Grant
-
6208250
-
Patent Number
6,208,250
-
Date Filed
Friday, March 5, 199925 years ago
-
Date Issued
Tuesday, March 27, 200123 years ago
-
Inventors
-
Original Assignees
-
Examiners
- Lee; Benjamin C.
- Nguyen; Tai T.
Agents
- Bose McKinney & Evans LLP
-
CPC
-
US Classifications
Field of Search
US
- 340 5731
- 340 572
- 340 82536
- 340 664
- 340 665
- 340 666
- 340 667
- 340 6861
- 340 562
- 340 517
- 340 521
- 340 522
- 340 523
-
International Classifications
-
Abstract
An apparatus is provided for detecting a position of a body on a support surface of a bed. The apparatus includes at least one first sensor coupled to the bed and at least one second sensor located adjacent the support surface. The at least one first sensor has an output signal which is variable in response to changes in a weight applied to the support surface. The at least one second sensor has an output signal which is variable in response to changes in the position of the body on the support surface. The apparatus also includes a controller having inputs configured to receive the output signals from the first and second sensors. The controller is configured to monitor the output signals, to provide an indication of changes in the position of the body relative to the support surface, and to provide an indication if the body exits the support surface.
Description
BACKGROUND SUMMARY OF THE INVENTION
The present invention relates to a patient position detection apparatus for a bed. More particularly, the present invention relates to a bed exit and patient position detection apparatus which has multiple modes of operation for providing information to a caregiver regarding a location of a patient on a support deck of the bed and for providing an indication when the patient has exited the bed.
When a patient is required to stay in a hospital bed at a hospital or other patient care facility, it is desirable for a caregiver to be able to monitor the presence, absence, and location of the patient on the bed support surface and to monitor the patient's activity level. Caregivers within a hospital or other patient care facilities are continuously responsible for more and more activities. One of these activities is monitoring patients who need to be restricted to the bed or patients that are at a risk of falling or aggravating injuries if they exit the bed. Patients having certain patient profiles, such as confusion, weakness, or disorientation, are more likely to be injured or reinjured if they exit the bed. Patients with certain types of medical conditions therefore require monitoring of both their presence on the bed and their or location on the support surface. In this instance, the present invention provides an alarm when the patient moves out of the predetermined position on the bed, prior to exiting the bed.
Some patients are allowed by doctor's orders to move about freely on the bed in order to access the bed controls, a phone, or other items or to reposition themselves for comfort. In this situation, an alarm is only required if the patient totally exits the bed.
The present invention provides dual sensor mechanisms for detecting the location of the patient on the bed and for detecting bed exit. Therefore, the caregiver may select from various modes of operation depending upon the patient condition and profile. The apparatus of the present invention detects the presence or absence of the patient on the bed and also detects the position of the patient on the support surface. Therefore, the present invention allows proper patient monitoring to be applied at the discretion of the caregiver for the correct patient situation.
The apparatus of the present invention utilizes two different sensor technologies integrated into the support sections of the hospital bed frame and deck. A controller monitor inputs from both types of sensors and, depending upon the mode selected by the caregiver, results in an alarm or no alarm based on detected sensor conditions.
In an illustrated embodiment of the invention, a first set of sensors includes load cells mounted on a base frame of the bed to support a weigh frame. As weight is applied to the bed, such as when a patient enters the bed, the controller detects voltage changes from the load cells. A second set of sensors is located below the patient. These second sensors are illustratively pressure sensitive sensors, such as resistive sensors which are located on the support deck or within the mattress. As pressure is applied to these sensors, such as when a patient lies on the mattress, a resultant voltage corresponds to the amount of pressure applied to a particular sensor. As the patient moves about the bed, sensor resistances change accordingly, thereby providing the controller with data to analyze regarding patient positions.
Each sensor provides an input to the common controller and all of the inputs are evaluated by the controller. When certain weight distribution changes are detected, an audible or visual alarm is activated. The criteria for activating the alarm is dependent upon the particular mode of operation for the overall system. Multiple modes of operation are selected by a switch, knob, button, etc. located on the bed, and preferably on a siderail of the bed. It is understood that a control panel on a pendant or remote control input device electrically coupled to the controller may be used to select the modes.
In an out-of-bed mode, an alarm is activated only when a patient completely exits the bed. In an exiting mode, an alarm is activated when a patient is located at a pre-exit position near the sides or ends of the support surface of the bed. Finally, in a position mode, an alarm is activated when a patient moves away from a head support surface on the deck located beneath the patient's head and back, such as when the patient has rolled against a siderail of the bed or has sat up in bed. Therefore, position mode provides an alarm earlier than exiting mode.
In the exiting mode and position mode, an alarm will also be activated if the patient exits the bed. In other words, in exiting mode and position mode, the out-of-bed detector is also used.
The alarm tones of the apparatus may be selected from a number of various tone options. Different sounds or visual indicators may be provided for each of the modes, if desired. In one illustrated embodiment, the patient positioning system is configured to deactivate the alarm if the patient gets back into bed or returns to the correct position on the bed. The apparatus also includes a button, switch, etc. located on the bed which will send a signal to reset or clear the “nurse call” alarm which is activated at a remote nurse station when a patient alarm is generated by the apparatus. This button allows the nurse to clear the remote bed exit/patient position alarm while at the bed after responding to the alarm. Currently, nurses have to clear the bed exit/patient position alarm by returning to the nurse call station or by deactivating the alarm somewhere else in the hospital, other than at the bed. Another illustrated embodiment of the invention is configured to turn on the room lights when an alarm is activated.
According to an illustrated embodiment of the present invention, an apparatus is provided for detecting a position of a body on a support surface of a bed. The apparatus includes at least one first sensor coupled to the bed and at least one second sensor located adjacent the support surface. The at least one first sensor has an output signal which is variable in response to changes in a weight applied to the support surface. The at least one second sensor has an output signal which is variable in response to changes in the position of the body on the support surface. The apparatus also includes a controller having inputs configured to receive the output signals from the first and second sensors. The controller is configured to monitor the output signals, to provide an indication of changes in the position of the body relative to the support surface, and to provide an indication if the body exits the support surface.
In the illustrated embodiment, the first and second sensors are different types of sensors. The at least one first sensor is illustratively a load cell or other suitable sensor. The at least one second sensor is illustratively a resistive pressure sensor, a capacitance sensor, a piezoelectric sensor, or other suitable sensor.
The bed illustratively includes a base frame and a weigh frame. The weigh frame is configured to support the support surface of the bed. The at least one first sensor includes a plurality of load cells configured to couple the weigh frame to the base frame. Each of the plurality of load cells is electrically coupled to the controller.
The support surface of the bed illustratively includes a deck and a mattress located on the deck. In one embodiment, the at least one second sensor is coupled to the mattress. The at least one second sensor is either coupled to a top or bottom surface of the mattress or located within an interior region of the mattress.
In another illustrated embodiment, the at least one second sensor is coupled to the deck. The deck illustratively includes a head deck section, a seat deck section, a thigh deck section, and a leg deck section. The second sensors illustratively include at least one head sensor coupled to the head deck section, at least one seat sensor coupled to the seat deck section, and at least one thigh sensor coupled to the thigh deck section.
In the illustrated embodiment, the head sensor is an elongated strip which extends in a direction parallel to a longitudinal axis of the deck. The head sensor is located at a center portion of the head deck section. Two elongated thigh sensors are illustratively coupled to the thigh deck section. The elongated thigh sensors illustratively extend in a direction parallel to the longitudinal axis of the deck. The seat sensor is an elongated strip which is configured to extend in a direction transverse to the longitudinal axis of the deck. The second sensors may further include at least one leg sensor coupled to the leg deck section.
The illustrated apparatus further includes an alarm coupled to the controller. The controller has a first mode of operation in which the alarm is activated by the controller only when the at least one first sensor detects that the body has exited the bed, a second mode of operation in which the alarm is activated by the controller when the at least one second sensor detects that the body has moved away from a central portion of the support surface, and a third mode of operation in which the alarm is activated by the controller when the at least one second sensor detects that the body has moved away from a central portion of a head section of the deck.
The illustrated apparatus further includes first, second, and third mode indicator lights located on the bed which correspond to the first, second, and third modes of operation of the controller, respectively. The controller is coupled to the first, second, and third mode indicator lights. The controller is configured to illuminate the first mode indicator light when the controller is in the first operation mode, to illuminate the first and second mode indicator lights when the controller is in the second operation mode, and to illuminate the first, second, and third mode indicator lights when the controller is in the third operation mode.
The illustrated apparatus includes a control panel coupled to the controller to permit a caregiver to select between the first and second modes of operation. The control panel is illustratively either coupled to a siderail of the bed, located on a pendant coupled to the controller, coupled to the controller by a remote control transmitter, or located elsewhere on the bed.
In an alternative embodiment of the present invention, the controller is configured to activate the alarm when the patient is out of a predetermined position on the support surface. The controller is also configured to detect when the body moves back into the predetermined position on the support surface and automatically deactivate the alarm upon detection of the body moving back into the predetermined position on the support surface.
In yet another embodiment, the controller is configured to monitor movement of the body on the support surface. The controller is configured to generate an output signal if a predetermined amount of movement of the body is not detected within a predetermined period of time.
In an illustrated embodiment, the controller includes an output coupled to a communication port to provide a nurse call alarm upon detection of the body moving out of a predetermined position on the support surface of the bed. A nurse call clear actuator is coupled to the bed. The nurse call clear actuator is configured to clear the nurse call alarm. The controller also is configured to transmit an output signal through the communication port to a remote location over a communication network.
According to another illustrated embodiment of the present invention. An apparatus is provided for detecting a position of a body on a support surface of a bed. The apparatus includes at least one sensor coupled to the bed. The at least one sensor has an output signal which is variable in response to changes to in the position of the body on the support surface. The apparatus also includes an alarm and a controller having at least one input configured to received the output signal from the at least one sensor and an output coupled to the alarm. The controller has at least two different modes of operation to monitor the position of the body on the support surface and generate an alarm signal to activate the alarm if predetermined conditions are met. The apparatus further includes a control panel coupled to the controller. The control panel includes a key button and a separate mode button to permit a caregiver to change the mode of operation of the controller. The controller is configured to permit a caregiver to adjust the mode of operation by pressing the mode button only when the key button is also pressed.
The control panel is illustratively coupled to a siderail of the bed, located on a pendant coupled to the controller, coupled to the controller by a remote control transmitter, or located elsewhere on the bed. The illustrated control panel also includes an alarm volume control button. The controller being configured to permit the caregiver to adjust the volume of the alarm using the volume control button only when the key button is also pressed. In other illustrated embodiments, the control panel includes an actuator to permit a tone of the alarm to be selected from a plurality of different tones, and the controller is configured to turn on a room light wherein the alarm signal is generated.
In the illustrated embodiment, the controller has first, second and third different modes of operation. The alarm is activated by the controller when different levels of patient movement on the support surface are detected for the first, second and third modes of operation. The apparatus also includes first, second, and third mode indicator lights located on the control panel which correspond to the first, second, and third modes of operation of the controller, respectively. The controller is coupled to the first, second, and third mode indicator lights. The controller is illustratively configured to illuminate the first mode indicator light when the controller is in the first operation mode, to illuminate the first and second mode indicator lights when the controller is in the second operation mode, and to illuminate the first, second, and third mode indicator lights when the controller is in the third operation mode.
According to yet another illustrative embodiment of the present invention, a bed includes a base, a support surface coupled to the base, a controller configured to control an entertainment device including at least one of a television, a radio, a stereo, a video player, and a computer, and an entertainment control panel coupled to the controller. The entertainment control panel includes inputs to permit an operator to control operation of the entertainment device. The apparatus also includes a lockout switch coupled to the controller. The lockout switch is configured to disable the entertainment control panel when the lockout switch is actuated.
In the illustrated embodiment, an indicator light is coupled to the controller. The indicator light is illuminated when the lockout switch is actuated. The indicator light is illustratively coupled to a siderail of the bed spaced apart from the lockout switch. The lockout switch is illustratively coupled to a footboard of the bed. A cover is coupled to the footboard. The lockout switch being concealed beneath the cover.
According to still another embodiment of the present invention, a bed includes a base, a support surface coupled to the base, a controller configured to control a plurality of functions including at least one of a night light, a back light, a head articulation actuator, a knee articulation actuator, a hi/lo actuator, and an entertainment device, and a control panel coupled to the controller. The control panel includes a plurality of inputs to permit an operator to control the plurality of functions. The apparatus also includes a plurality of lockout switches coupled to the controller and an indicator located on the bed spaced apart from the plurality of lockout switches. The controller is configured to disable operation of selected functions by the control panel upon actuation of corresponding lockout switches. The indicator is configured to provide an indication when at least one of the lockout switches is actuated to disable operation of at least one of the functions.
Illustratively, the indicator is coupled to a siderail of the bed and the plurality of lockout switches are located on a footboard of the bed. Each of the plurality of lockout switches illustratively includes a separate light located adjacent the lockout switch to indicate when the lockout switch is actuated.
According to a further embodiment of the present invention, an apparatus is provided for aligning a first electrical connector electrically coupled to a control panel located on a removable member of a bed with a second electrical connector electrically coupled to a controller on the bed. The apparatus includes a first connector alignment apparatus having a connector receiving portion configured to secure the first electrical connector to the first connector alignment apparatus, a second connector alignment apparatus having a connector receiving portion configured to secure the second electrical connector to the second connector alignment apparatus, a first fastener configured to couple the first connector alignment apparatus to the removable member of the bed, and a second fastener configured to couple the second connector alignment apparatus to a frame of the bed. One of the first and second connector alignment apparatuses includes at least one alignment post, and the other of the first and second connector alignment apparatuses includes at least one aperture configured to receive the alignment post therein as the removable member is installed on to the frame of the bed to align the first and second electrical connectors before the first and second connectors are mated.
In the illustrated embodiment, the frame of the bed includes at least one post extending away from the frame by a distance greater than a height of the second connector alignment apparatus. The removable member of the bed is formed to include an aperture configured to receive the post on the frame of the bed to provide an initial alignment between the removable member and the frame as the removable member is installed on to the frame. The first electrical connector includes at least one alignment post and the second electrical connector includes an aperture configured to receive the alignment post of the first electrical connector therein to provide further alignment between the first and second electrical connectors.
In the illustrated embodiment, the first fastener is configured to provide a rigid connection between the first connector alignment apparatus and the removable member, and the second fastener is configured provide a loose connection between the second connector alignment apparatus and the frame to permit limited movement of the second connector alignment apparatus relative to the frame. The frame of the bed is illustratively formed to include at least one aperture. The second electrical connector alignment apparatus illustratively includes at least one retention post configured to be inserted into the at least one aperture of the frame. The at least one aperture of the frame is larger than the at least one retention post to permit the limited movement of the second connector alignment apparatus relative to the frame of the bed.
Additional features and advantages of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of illustrated embodiments exemplifying the best mode of carrying out the invention as presently perceived.
BRIEF DESCRIPTION OF THE DRAWINGS
The detailed description particularly refers to the accompanying figures in which:
FIG. 1
is a perspective view of a hospital bed which includes a patient position detection apparatus in accordance with the present invention and which includes a footboard having an electrical connector alignment apparatus of the present invention;
FIG. 2
is an end view of the footboard of
FIG. 1
illustrating further details of the electrical connector alignment apparatus;
FIG. 3
is an exploded perspective view of portions of the hospital bed of
FIG. 1
illustrating a base frame, a weigh frame, an intermediate frame, a retracting frame, an articulating deck, a first set of sensors for detecting the weight of a patient on the deck, and a second set of sensors located on the articulating deck for detecting the position of the patient on the deck;
FIG. 4
is a partial sectional view illustrating a load cell configured to connect the weigh frame to the base frame;
FIG. 5
is a perspective view of a head end siderail which includes a control panel for operating the patient position detection apparatus of the present invention;
FIG. 6
is an enlarged view of the control panel of
FIG. 5
which is used to control the mode of operation of the patient position detection apparatus and the volume of the alarms generated by the detection apparatus;
FIG. 7
is a block diagram illustrating the control electronics of the patient position detection apparatus;
FIG. 8
is a top plan view of the articulating deck of the bed with the second set of sensors mounted on the deck;
FIGS. 9 and 10
are flow charts illustrating a main loop of steps performed by the controller for monitoring inputs from the control panel and the first and second sets of sensors to control operation of the patient position detection apparatus in a position mode, an exiting mode, and an out-of-bed mode;
FIG. 11
is a flow chart illustrating steps performed by the controller in the position mode;
FIG. 12
is a flow chart illustrating steps performed by the controller in the exiting mode;
FIG. 13
is a flow chart illustrating steps performed by the controller in the out-of-bed mode;
FIG. 14
is a perspective view of a first electrical connector alignment apparatus configured to be coupled to the footboard of the bed;
FIG. 15
is a perspective view of a second electrical connector alignment apparatus configured to be coupled to the retracting frame of the bed; and
FIG. 16
is an exploded perspective view illustrating the first and second electrical connector apparatuses with electrical connectors installed therein and located on the footboard and retracting frame, respectively.
DETAILED DESCRIPTION OF THE DRAWINGS
Referring now to the drawings,
FIG. 1
illustrates a hospital bed
10
of the present invention. The bed
10
includes a base frame
12
having a plurality of casters
14
and brake/steer control pedals
16
mounted adjacent each of the casters
14
. Details of the operation of the brake/steer control mechanism are disclosed in co-pending U.S. patent application Ser. No. 09/263,039(attorney docket 7175-63003, entitled CASTER AND BRAKING SYSTEM), filed concurrently, herewith which is hereby incorporated by reference.
As best shown in
FIG. 3
, the bed
10
includes a weigh frame
18
coupled to the base frame
12
, an intermediate frame
19
coupled to the weigh frame
18
, a retracting frame
20
coupled to the intermediate frame
19
, and an articulating deck
22
coupled to the intermediate frame
19
and the retracting frame
20
. Brackets
21
on opposite sides of frame
20
are configured to be coupled between the head section
106
and the thigh section
110
of deck
22
with suitable fasteners (not shown).
Referring again to
FIG. 1
, the bed
10
includes a headboard
24
mounted adjacent a head end
26
of the bed
10
and a footboard
28
mounted to the frame
20
adjacent a foot end
30
of bed
10
. Bed
10
further includes a pair of head end siderails
32
and a pair of foot end siderails
34
mounted to the articulating deck
22
on opposite sides of the bed
10
. Further details of head end siderail
32
are illustrated in FIG.
5
. Siderails
32
and
34
are coupled to the articulating deck
22
in a conventional manner using a connector mechanism
35
best shown in FIG.
5
. The siderails
32
and
34
are movable from a lowered position shown in
FIG. 1
to an elevated position (not shown) located above a top surface
36
of mattress
38
. Mattress
38
is located on articulating deck
22
for supporting a patient thereon.
The footboard
28
includes a plurality of buttons, knobs, switches or other controls
40
for controlling various functions of the bed
10
. Controls
40
are located on a top inclined panel
42
and a bottom inclined panel
44
on the footboard
28
. A cover
46
is pivotably coupled to the footboard
28
by a pivot connection
48
so that the cover can be pivoted downwardly to conceal at least the controls
40
located on the top inclined panel
42
.
One of the controls on the footboard
28
is illustratively a lockout button
61
for entertainment functions which are controlled by patient input control panels on the bed
10
. In other words, a caregiver can press button
61
to lock out entertainment functions on the bed
10
. An indicator light is provided adjacent the entertainment lockout control
61
to provide an indication when the entertainment lockout
61
is activated. When the entertainment lockout
61
is activated, the patient cannot turn on the television, radio, stereo, video player, computer or other entertainment device typically available on the bed or in the room. The entertainment lockout control
61
is illustratively located below the cover
46
on the footboard
28
. It is understood, however, that the entertainment lockout may be located at other positions on the bed.
The bed
10
also includes a plurality of lockout switches
63
which are illustratively located on the footboard
28
. It is understood that the lockout switches
63
may be located at any other position on the bed
10
. The lockout switches
63
are coupled to the controller
50
to pen-it a caregiver to lock out selected functions which are normally controlled by the patient. Using patient controls that are typically located on the head end siderails
32
. For example, lockout switches
63
may deactivate controls for a night light, a back light, head or knee articulation, a hi/lo mechanism, or the entertainment devices discussed above. In addition, a master lockout switch is provided to lock out the head and knee articulation and the hi/lo control mechanism controls.
Panel
42
illustratively includes an indicator light (not shown) adjacent each of the lockout switches
63
to provide an indication when a particular lockout switch
63
is pressed. In addition, the bed
10
includes a separate lockout indicator light
65
located at a location on the bed
10
spaced apart from the lockout switches
63
. In the illustrated embodiment, the separate lockout indicator light
65
is located on the head end siderail
32
as shown in FIG.
5
. Indicator light
65
provides the nurse with a visual indication that one of the lockout switches
63
has been pressed.
Footboard
28
also includes side bumpers
66
and apertures
68
. Apertures
68
provide handles to facilitate movement of the bed
10
. Illustratively, headboard
24
and footboard
28
are made from a plastic material using a blow molding process. It is understood, however, that the headboard
24
and footboard
28
may be made from other materials and from other processes, if desired.
The controls
40
on the footboard
28
are electrically coupled to a controller
50
shown in FIG.
3
. The controller
50
and other bed electronics are illustratively mounted on frame
20
. A first connector alignment apparatus
52
is coupled to the footboard
28
and a second connector alignment apparatus
54
is coupled to the frame
20
. As shown in
FIGS. 2 and 3
, footboard
28
is formed to include apertures
56
which slide over posts
58
on the frame
20
during installation of the footboard
28
onto the frame
20
in the direction of arrow
60
in FIG.
3
. Posts
58
and apertures
56
therefore provide initial alignment between the footboard
28
and the frame
20
. First and second connector alignment apparatuses
52
and
54
provide further alignment for male and female electrical connectors
62
and
64
, respectively, as discussed in detail below with reference to
FIGS. 14-16
.
The patient position detection apparatus of the present invention uses two different types of sensors
70
,
104
. A first set of sensors
70
is used to detect when a patient exits the bed
10
. A second set of sensors
104
is used to determine a position of the patient on the deck
22
of the bed
10
. In the illustrated embodiment, the first type of sensors include load cells
70
which are mounted at the four corners of the weigh frame
18
. Details of the mounting of the load cells
70
between the base frame
12
and the weigh frame
18
are illustrated in
FIGS. 3 and 4
. Base frame
12
includes side frame members
72
and transverse frame members
74
extending between the side frame members
72
. Weigh frame
18
includes a pair of hollow side frame members
76
. Load cells
70
are well known. Load cells
70
typically include a plurality of strain gauges located within a metal block.
As best shown in
FIG. 4
, a mounting ball
78
is coupled to the load cell
70
. Illustratively, mounting ball
78
includes a threaded stem which is screwed into threads in the load cell
70
. Mounting ball
78
is located within an aperture
80
formed in a mounting block
82
. Mounting blocks
82
are secured to the transverse frame members
74
by suitable fasteners
84
at the four comers of the base frame
12
. A mounting bar
86
is coupled to an arm
88
of load cell
70
by fasteners
90
. Mounting bar
86
is then secured to a top surface
92
of side frame member
76
of weigh frame
18
by suitable fasteners
94
and washers
96
. Mounting bar
86
is not coupled to arm
98
of load cell
70
. Therefore, load cell
70
may be deflected downwardly in the direction of arrow
100
when weight is applied to the weigh frame
18
. Such deflection in the direction of arrow
100
changes an output voltage which provides an indication of weight change on the weigh frame. Load cells
70
are coupled to a signal conditioner
53
by wires
102
. The signal conditioner
53
is then coupled to the controller
50
on the bed
10
by wires
102
.
Although the specification and claims of this application refer to a controller
50
, it is understood that the bed
10
will typically include several controllers which control different functions on the bed. These controllers may be located at any location on the bed and are not limited to the location illustrated in FIG.
3
. The controllers
10
typically are microprocessor based controllers. Output signals from various devices may need to be conditioned prior to being coupled to the controller. For instance, analog signals may need to be converted to digital signals for processing by the microprocessor of the controller. Therefore, the word controller is used broadly to include any type of control circuitry necessary to process the output signals and produce the desired control outputs or signals.
A second set of sensors
104
is illustrated in
FIGS. 3 and 8
. Articulating deck
22
includes a head deck section
106
, a seat deck section
108
, a thigh deck section
110
, and a leg deck section
112
. The second set of sensors
104
includes a head section sensor
104
coupled to head deck section
106
by fasteners
116
. Sensor
114
is elongated and extends along a longitudinal axis
118
of the deck
22
. Seat sensor
120
is coupled to seat deck section
108
by fasteners
116
. Sensor
120
extends in a direction transverse to the longitudinal axis
118
. Thigh sensors
122
and
124
are coupled to thigh deck section
110
by fasteners
116
. The locations of sensors
114
,
120
,
122
,
124
are further illustrated in FIG.
8
.
Illustratively, sensors
114
,
120
,
122
, and
124
are resistive pressure sensors available from Interlink Electronics. The resistive pressure sensors are formed in strips which can be cut to any desired length. The sensor strips are illustratively adhered to a stiffener and then scaled within a protective outer sleeve or cover made from a wipable material. Fasteners
116
are illustratively rivets which secure the sensors
114
,
120
,
122
, and
124
in position on the deck
22
as best shown in FIG.
8
. Sensors
114
,
120
,
122
, and
124
are coupled to the controller
50
on the bed
10
by wires
126
.
As pressure on the sensors
114
,
120
,
122
, and
124
increases, resistance of the sensors is lowered. By processing the output signals from sensors
114
,
120
,
122
, and
124
, the controller
50
determines the position of the patient on the deck
22
. In particular, the controller
50
determines when the patient moves away from a central portion of the bed and too close to the side edges
23
or
25
on the deck
22
. Controller
50
then provides an indication that the patient is at risk of exiting the bed.
Using the two different types of sensors
70
and
104
, the patient position detection apparatus of the present invention is capable of operating in several different modes to assist the caregiver with tracking the patient position on the bed
10
. In an out-of-bed mode, only sensors
70
are used to activate an alarm when a patient completely exits the bed. In a second exiting mode, both sets of sensors
70
,
104
are used. An alarm is activated when a patient is located at a position near the sides
23
,
25
of deck
22
or on the deck
22
near the head end
26
or foot end
30
. In other words, a pre-exit alarm is sounded when the patient moves outside a central portion of the deck
22
on the bed
10
. In a third position mode, both sets of sensors
70
,
104
are also used. An alarm is activated when a patient moves away from the head sensor
114
on the deck
22
as discussed below.
FIG. 7
is a block diagram illustrating the electronic control components of the patient position detection apparatus. As discussed above, the first and second sensors
70
and
104
are each coupled to the controller
50
. The controller
50
processes signals from the first and second sensors
70
,
104
as discussed in detail below to provide various control functions. A caregiver control panel
130
is mounted on the bed
10
to control operation of the patient position detection apparatus. Preferably, the caregiver control panel
130
is mounted on the head end siderail
52
as best shown in FIG.
5
. The control panel
130
may also be on a pendant or on a remote control device electrically coupled to the controller
50
. The caregiver control panel
130
includes control buttons, switches, knobs, etc. for setting the particular type of tone for the audible alarm and for setting a volume of the alarm for each of the detection modes as illustrated at block
132
. In addition, the caregiver control panel
130
includes control buttons, switches, knobs, etc. to set the particular type of detection mode for the apparatus as discussed below. Inputs from the caregiver control panel
130
are transmitted to the controller
50
. Controller
50
also transmits signals to the caregiver control panel
130
to control indicator lights
136
on the caregiver control panel
130
.
If an alarm condition is detected by controller
50
as discussed below in detail, controller
50
controls either audible or visual local alarms
138
within the room or on the bed
10
. Controller
50
may also be used to turn on the room lights
140
when an alarm condition is detected. Finally, the controller
50
activates a nurse call alarm
142
to send an indication of the alarm condition to a nurse station located at a remote location.
The apparatus of the present invention further includes a nurse call reset or clear button
144
located on the bed
10
. This clear button
144
sends a signal to controller
50
to clear the nurse call
142
alarm once the nurse call
142
alarm has been activated at the remote nurse call station. Nurse call clear button
144
permits the caregiver to clear or reset the remote patient alarm while at the bed
10
after responding to the alarm condition. Currently, caregivers must cancel the nurse call bed exit alarm
142
by returning to the nurse call station or by deactivating the alarm somewhere else in the hospital, other than at the bed
10
. Button
144
permits the caregiver to clear the nurse call bed exit alarm
142
after responding to the alarm condition at the bed
10
. Controller
50
is also coupled to a communication network
55
so that the controller
50
can transmit output signals to a remote location.
In an alternative embodiment of the present invention, controller
50
is programmed to deactivate the local alarm
138
if the patient returns to bed
10
or returns to a correct position on the bed
10
depending upon the mode selected. This feature may encourage the patient to return to the correct position on the bed
10
since the alarm will be deactivated when the patient returns to the correct position. The nurse call alarm
142
typically remains activated so that the caregiver may still respond to the alarm, even if the local audible and visual room alarm
138
is deactivated.
FIG. 6
illustrates further details of the caregiver control panel
130
which is illustratively located on the head end siderail
132
. Control panel
130
includes a key button
150
, a mode control button
152
, and a volume control button
154
. In order to adjust the detection mode or volume of the alarm, the caregiver must depress the key button
150
and hold it down while depressing the desired mode button
152
or volume button
154
. With the key button
150
held down, the caregiver can scroll through the modes of operation by pressing the mode button
152
. Separate indicator LEDs are provided to indicate which mode is selected. The Position Mode is indicated by LED
156
, the Exiting Mode is indicated by LED
158
, and the Out-of-Bed Mode is indicated by LED
160
. If none of the LEDs
156
,
158
,
160
is lit, the patient position detection apparatus is off.
If the Position Mode is selected, all three LEDs
156
,
158
, and
160
are lit. If the Exiting Mode is selected, LEDs
158
and
160
are lit. If the Out-of-Bed Mode is selected, only LED
160
is lit. By providing a different number of indicator lights for each of the three modes, a caregiver can tell which mode is selected in the dark.
By requiring the depression of both the key button
150
and the mode button
152
or volume button
154
and by placing these buttons
150
,
152
,
154
on the caregiver side of the siderail
32
, the patient is deterred from changing modes or volumes. The caregiver can change the volume of the alarm between a high setting, a medium setting, and a low setting by pressing the key button
150
and simultaneously pressing the volume button
154
. Subsequent presses of the volume button
154
change the volume to different levels. Indicator LEDs
162
,
164
, and
166
are provided for the high, medium, and low volumes, respectively. If the high volume level is selected, all three LEDs
162
,
164
, and
168
are lit. If the medium volume level is selected, LEDs
164
and
168
are lit. If the low volume level is selected, only LED
168
is lit. By providing a different number of indicator lights for each volume level, a caregiver can tell the volume level for the alarm in the dark. When the patient position detection apparatus is off, all the volume LEDs
162
,
164
, and
168
are off.
When a local alarm condition is detected by controller
50
as discussed below. An appropriate LED for Position Mode, Exiting Mode, and Out-of-Bed Mode will flash on the control panel
30
to indicate an alarm condition for that mode. More than one of the LEDs
156
,
158
, and
160
can flash. For instance, in Position Mode, the Position Mode LED
156
may begin to flash when an alarm condition is detected by the Position Mode. Since the Out-of-Bed Mode is also run in Position Mode, the Out-of-Bed LED
160
may also be flashing if the patient has exited the bed.
Caregiver control panel
130
also includes an indicator LED
170
to provide an indication that the bed
10
is not down. This indicator LED
170
is lit when the deck
22
is not in its lowest position relative to the floor. In addition, caregiver panel
130
includes an indicator LED
172
which provides an indication when the brake on the casters
14
is not set. When positioned in a room, the bed
10
is typically set so that the deck
22
is in its lowest position and the brake is set. Therefore, indicator LEDs
170
and
172
provide the caregiver with an indication that these conditions are not met.
FIG. 8
shows the illustrative arrangement of the sensors
114
,
120
,
122
, and
124
on the articulating deck
22
. It is understood that other arrangements of the second set of sensors
104
may be used in accordance with the present invention. In addition, additional sensors may be provided such as a sensor
125
located on the leg deck section
112
. Although the second sensors
104
are illustratively resistive sensors, it is understood that other types of sensors may be used in accordance with the present invention. For example, capacitance sensors such as shown in U.S. Pat. No. 5,808,552 or in pending U.S. patent application Ser. No. 09/031,749, which are incorporated herein by reference, may be used as the second sensors. In addition, a piezoelectric sensor such as disclosed in co-pending U.S. application Ser. No. 09/263,038 (attorney docket 7175-63002, entitled A MONITORING SYSTEM AND METHOD) filed concurrently herewith which is hereby incorporated by reference may also be used. In another embodiment, the sensors
104
are coupled to a stop or bottom surface of the mattress
38
or are located within an interior region of the mattress
38
.
FIGS. 9-12
are flow charts illustrating operation of the controller
50
of the present invention and each of the three patient position detection modes. The main software loop of the controller
50
is illustrated in
FIGS. 9 and 10
. The main loop begins at block
200
of FIG.
9
. Controller
50
first updates the status of the indicator lights
136
on control panel
130
or elsewhere as illustrated at block
202
. Controller
50
then determines whether the patient detection system is on at block
204
. If the detection system is not on, controller
50
advances to block
230
as illustrated at block
205
. If the patient detection system is on, controller
50
checks the mode of the detection system as illustrated at block
206
. Specifically, controller
50
determines whether the detection system is in position mode as illustrated at block
208
, exiting mode as illustrated at block
210
, or out-of-bed mode as illustrated at block
212
.
If the controller is in position mode as illustrated at block
208
or exiting mode as illustrated at block
210
, the controller
50
will run the control loops for these modes as discussed below. After running the positioning mode loop or the exiting mode loop, the controller
50
will also run the out-of-bed mode loop when the controller is set in position mode or exiting mode. In other words, if the detection system is on, the out-of-bed mode will always be checked.
Controller
50
then determines whether the mode was just activated at block
214
. If the particular mode was not just activated, the controller
50
advances to block
246
of
FIG. 11
if the system is in position mode as illustrated at block
216
. If the particular mode was not just activated, controller
50
advances to block
264
of
FIG. 12
if the system is in exiting mode as illustrated at block
218
. If the particular mode was not just activated, controller
50
advances to block
278
of
FIG. 13
if the system is in out-of-bed mode as illustrated at block
220
.
If the mode was just activated at block
214
, controller
50
reads all the sensor values from the first and second sets of sensors
70
and
104
as illustrated at block
222
. Controller
50
then determines whether the sensor values are within the preset specifications as illustrated at block
224
. In the position mode, controller
50
is only concerned with the head sensor
114
. Therefore, in position mode, the output from head sensor
114
is checked. The output value from sensor
114
is within specification if the head sensor
114
output signal corresponds to a range of weights between 50-450 lbs. Therefore, for position mode, the sensor
114
is typically not within specification if the head sensor
114
is not plugged in, shorted, or if a patient is not on the bed
10
.
For exiting mode, controller
50
checks all the load cells
70
and sensors
114
,
120
,
122
, and
124
. To be within specification for exiting mode, the weight range detected by load cells
70
must be within a predetermined range based on average human weights. Controller
50
also determines whether any of the sensors
114
,
120
,
122
, or
124
are not plugged in or are shorted. In the out-of-bed mode, controller
50
only looks at load cells
70
to make sure that at least a predetermined minimum weight reading is obtained in order to indicate that a patient is on the bed
10
.
If the values read at block
222
are not within specifications, controller
50
will send a local alarm as illustrated at block
226
so that the caregiver can investigate the problem as illustrated at block
226
. Controller
50
then turns the detection system off as illustrated at block
227
and advances to block
230
as illustrated at block
229
. If the retrieved sensor values are within the specifications at block
224
, controller
50
stores all the sensor values in memory
51
as illustrated at block
228
. Controller
50
then advances to block
230
as illustrated at block
229
.
In the illustrated embodiment, the key button
150
on control panel
130
is a hardware switch. If the key button
50
is not pressed, the controller
50
does not receive the signal from the mode button
152
or the volume button
154
. Therefore, if the key button is not pressed as illustrated at block
232
, controller
50
returns to block
200
as illustrated at block
244
. If the key button
150
and the mode button
152
are pressed as illustrated at block
234
, the controller
50
will receive an input based on the mode button press. If the key button
150
and the volume button
154
are pressed as illustrated at block
236
, the controller
50
will receive an input signal from the volume button
154
press. If the key button
150
, the mode button
152
, and the volume button
154
are all pressed as illustrated at block
238
, the controller
50
will receive input signals from both the mode button press and the volume button press. If the key button and at least one other button are pressed at blocks
234
,
236
, and
238
, controller
50
will update the mode and volume settings in memory
51
as illustrated at block
240
. Controller
50
then returns to block
200
as illustrated at block
244
.
Operation of the controller
50
in position mode is illustrated beginning at block
246
of FIG.
11
. Controller
50
first reads the current value of head sensor
114
as illustrated at block
248
. The current head sensor value is abbreviated as CV. Next, controller
50
retrieves the stored value for head sensor
114
which was stored in memory
51
at block
228
as illustrated at block
250
. The stored sensor value is abbreviated as SV. Controller
50
then determines a scaler value based upon the stored head sensor value. In the illustrated embodiment, an 8 bit A/D converter is used to convert the output from the sensors
104
. Therefore, the value SV ranges from 1-256 in the illustrated embodiment. Smaller values of SV indicate larger weight on the sensors
104
. It is understood that this range could be varied depending upon the particular A/D converter used. Therefore, the range of 1-256 is only for illustrative purposes. Controller
50
sets the scaler value as illustrated in the table at block
252
. The scaler value remains constant until the mode is reactivated. Next, controller
50
calculates the acceptable range for the current head sensor value (CV) as illustrated at block
254
. The acceptable range is:
Controller
50
determines whether the current head sensor value CV is within the acceptable range as illustrated at block
256
. If so, controller
50
determines that the patient is in the proper position on the deck and returns to block
230
as illustrated at block
262
. If the current head sensor value is not within the acceptable range at block
256
, controller
50
determines whether a timer has expired at block
258
. If not, controller
50
advances back to block
230
. If the timer has expired, controller
50
determines that the patient is out of position and activates the local alarms
138
as illustrated at block
260
. Controller
50
also activates a nurse call alarm
142
, and may turn on the room lights
140
at block
260
. Controller
50
then advances to block
278
and runs the out-of-bed mode check as illustrated at block
262
.
Operation of the patient detection system in exiting mode is illustrated beginning at block
264
in FIG.
12
. Controller
50
advances to block
264
from block
218
in FIG.
9
. In exiting mode, controller
50
first runs the positioning mode loop as illustrated at block
266
. In other words, the controller
50
uses head sensor
114
to check the patient's position using the flow chart discussed above in reference to FIG.
11
. Controller
50
determines whether the current head sensor value CV is within the acceptable range as illustrated at block
268
. If so, controller
50
determines that the patient is in the proper position and advances to block
278
to run the out-of-bed mode check as illustrated at block
276
in FIG.
12
.
If the head sensor value is not within the acceptable range at block
268
, controller
50
runs a sensor test for seat sensor
120
and thigh sensors
122
and
124
using a similar test as in FIG.
11
. Scaler values may be adjusted for the different sensors
120
,
122
, and
124
, if necessary. Scaler values are selected by applying a known load above a particular sensor location and taking an output reading. Next, a predetermined distance from the sensor is selected at which point it is desired to activate the alarm. The known weight is than moved to that desired alarm location and another output reading is taken. The scaler value is calculated the percentage change between the output of the sensor when the known weight applied directly over the sensor and the output of the sensor when the known weight applied at the predetermined distance perpendicular to the sensor.
Controller
50
then determines whether two of the three remaining sensors
120
,
122
, and
124
are within acceptable ranges as illustrated at block
272
by comparing the current sensor values to ranges based on the corresponding stored sensory values. If so, controller
50
determines that the patient is in an acceptable position on the deck
22
and advances at block
230
as illustrated at block
276
. If two of the three sensors are not within the acceptable ranges at block
272
, controller
50
determines that the patient is out of position and updates the local alarms
238
, activates the nurse call alarm
142
, and may turn on the room lights
140
as illustrated at block
274
. Controller
50
then advances to block
230
as illustrated at block
276
. In exiting mode, the patient position detection apparatus of the present invention permits the patient to move around more on the deck
22
before an alarm is activated compared to the position mode. Therefore, position mode is the most sensitive setting for the patient position detection apparatus of the present invention.
It is understood that other configurations may be provided for the locations of sensors
104
. A different number of sensors
104
may be used. The sensors
104
may be mounted at different locations on the deck
22
, on the mattress
38
, or elsewhere on the bed
10
.
Operation of the patient position detection system in the out-of-bed mode is illustrated beginning at block
278
in FIG.
13
. Controller
50
advances to block
278
from block
220
in FIG.
9
. In the out-of-bed mode, controller
50
detects an average current weight of the patient as illustrated at block
280
. For instance, the controller
50
can take four readings from each load cell
70
and divide by four to get an average current weight. Next, controller
50
retrieves the stored initial weight from memory
51
as illustrated at block
282
. Controller
50
subtracts the stored weight from the current weight as illustrated at block
284
.
Next, controller
286
determines whether the weight on the bed
10
detected at block
280
has increased or decreased by more than 30 lbs. compared to the initial stored weight retrieved at block
282
. If the weight has not changed by more than 30 lbs., controller returns to block
230
) as illustrated at block
294
. If the weight has changed by more than 30 lbs. at block
286
, controller
50
determines whether a timer has expired at block
288
. If the timer has not expired, controller
250
advances to block
230
as illustrated at block
294
. If the timer has expired at block
288
, the controller
50
determines whether the difference calculated at block
284
is less than −30 lbs. at block
290
. If so, controller
50
determines that the patient has exited the bed
10
and updates the local alarms
138
, the nurse call alarm
142
and may turn on the room lights
140
as illustrated at block
292
. Controller
50
then returns to block
230
as illustrated at block
294
.
If the difference is not less than −30 lbs. at block
290
, controller
50
determines whether the difference calculated at block
284
is greater than 30 lbs. as illustrated at block
296
. If so, controller
50
determines that substantial additional weight has been added to the bed and updates local alarms
138
only as illustrated at block
298
. The nurse call alarm
142
may also be activated, if desired. Controller
50
then advances to block
230
as illustrated at block
294
. If the difference is not greater than 30 lbs. at block
296
, controller
50
clears the local alarm only at block
300
and then advances to block
230
as illustrated at block
294
.
It is understood that the 30 lbs. threshold value for the out-of-bed mode may be adjusted upwardly or downwardly depending upon the weight of the patient. In other words, if the patient is particularly heavy, the 30 lb. threshold may be increased, for example.
It is understood that the patient detection apparatus of the present invention may have more than three modes of operation if desired. The separate modes may have different sensitivity levels.
The out-of-bed mode of the present invention may be armed with the patient in the bed
10
. In some beds having scales, the patient must be removed in order to determine a tare weight of the bed prior to the patient getting into the bed in order to arm the bed exit detector. In the out-of-bed mode of the present invention, removing the patient from the bed is not required in order to arm the bed exit detection system.
The patient position detection system of the present invention may be quickly switched from a normal bed exit system in which an alarm is generated only when a patient exits the bed to a predictive bed exit system in which an alarm is generated when a patient moves away from a center portion of the bed. In an embodiment of the invention, the output signals from the first and second set of sensors
70
,
104
are monitored and stored, either at the bed
10
, or at a remote location to record movements of the patient. The controller
50
or a controller at the remote location monitors the sensor output values to determine whether the patient is moving on the bed
10
. In one embodiment, the controller
50
or controller at a remote location generates a caregiver alert signal or alarm if the patient has not moved on the bed within a predetermined period of time. Therefore, the caregiver can go to the bed
10
and rotate the patient in order to reduce the likelihood that the patient will get bed sores. For example, if the patient hasn't moved for a predetennined period of time, such as two hours, a signal is generated advising the caregiver to move the patient. If the sensors
70
,
104
and controller detect that the patient has moved within the predetermined period, then there is no need for the caregiver to go turn the patient. Therefore, no signal is generated. This feature saves caregiver time and reduces the likelihood of injuries due to unnecessary rotation of a patient who has been moving.
In another embodiment of the present invention, the output signals from the four sensors
70
located at the corners of the base frame
12
are used to provide an indication when one of the frames or the deck hits an obstruction when moving from the high position to a low position. In particular, the processor
50
determines when an output signal from one of the sensors
70
at the corners generates a negative value or a greatly reduced weight reading within a short period of time. This rapid change in the output signal indicates that an obstruction has been hit. Therefore, controller
50
can provide an output signal to stop the hi/lo mechanism from lowering the frames and deck. An alarm signal is also provided, if desired.
In another embodiment of the present invention, the controller
50
is configured to transmit data to a nurse station located at a remote location over the communication network
55
. This data illustratively includes information related to at least one of patient weight, the patient's position on the support surface of the bed
10
, a bed exit indicator, the mode of operation of the patient position detection apparatus, a brake not set indicator, a bed not down indicator, or other data related to the status of the bed or the status of the patient. This permits the nurse to detect the information related to the status of the bed or the status of the patient at the central nurse station without having to check each bed separately.
FIGS. 14-16
further illustrate the connector alignment apparatus of the present invention. The first connector alignment apparatus
52
is illustrated in
FIG. 14
, and the second connector alignment apparatus
54
is illustrated in FIG.
15
. Connector alignment apparatus
52
is configured to receive a first pair of electrical connectors
62
shown in
FIG. 16
which include a housing
304
having a first pair of spaced-apart flanges
306
and a second pair of spaced-apart flanges
308
. Flanges
308
are each formed to include an aperture
310
. Connectors
302
include a plurality of electrical terminals
312
extending away from housing
304
. Alignment posts
313
extend from housing
304
of connector
62
further than terminals
312
. The terminals
312
are electrically connected to conductors of a cable
314
. Cable
314
of connectors
62
are connected to controls
40
. Connector alignment apparatus
54
is configured to receive female electrical connectors
64
. Those numbers referenced by numbers on connectors
62
perform the same or similar function. Connectors
64
include female socket contacts
318
configured to receive terminals
312
of connector
302
. Illustratively, cables extending from connectors
64
are coupled to the controller
50
on bed
10
.
Referring now to
FIG. 14
, connector alignment apparatus
52
includes a base plate
320
having outwardly extending alignment posts
322
located at opposite ends. Posts
322
each include tapered head portions
324
. Alignment apparatus
52
includes a pair of connector receiving portions
326
. Connector receiving portions
326
each include a pair of center posts
328
. Each post
328
includes a pair of spring arms
330
. Each spring arm
330
has a head portion
332
including a ramp surface
334
and a bottom lip
336
. Each connector receiving portion
326
also includes a pair of posts
338
.
Electrical connectors
62
are installed into the connector receiving portions
326
by locating the apertures
310
on flanges
308
over the posts
338
and pushing the connector
62
toward base
320
. Flanges
306
engage ramp surfaces
334
of heads
332
and cause the spring arms
330
to be deflected. Once the flanges
306
move past the heads
332
, heads
332
then move over flanges
306
to retain the connectors
302
within the connector alignment apparatus
52
as best shown in FIG.
16
.
Second connector alignment apparatus
54
is best illustrated in FIG.
15
. The alignment apparatus includes a body portion
340
having a pair of downwardly extending alignment posts
342
. Body portion
340
is formed to include apertures
344
at opposite ends. Apertures
344
are configured to receive the posts
322
of first connector alignment apparatus
52
as discussed below. Lead-in ramp surfaces
346
are formed around the apertures
344
. Body portion
340
further includes a pair of connector receiving portions
348
which function the same as connector receiving portions
326
described above. Reference numbers the same as in
FIG. 14
perform the same or similar function. Apertures
310
formed in flanges
308
of connectors
64
are inserted over the posts
338
of the connector receiving portions
348
. The connectors
64
are then pushed downwardly to deflect the heads
332
until the lips
336
move over flanges
306
to lock the connectors
64
within the housing
340
as discussed above.
The first connector alignment apparatus
52
and the second connector alignment apparatus
54
each may include a key shown diagrammatically at locations
349
and
351
, respectively. Certain beds have different features which are controlled by controller
50
and actuated by controls
40
on the footboard. Therefore, different footboards
28
may be required depending upon the particular type of bed
10
being used. The keys
349
and
351
on the first and second connector alignment apparatuses
52
and
54
only permit connection between an appropriate type of footboard
28
for the particular bed
10
. Therefore, the keys
349
and
351
ensure that the right type of footboard
28
is attached to the bed
10
.
First connector alignment apparatus
52
is rigidly coupled within a recessed portion
350
formed in footboard
28
as best shown in FIG.
16
. The base
320
is secured to the footboard
28
by a fastener
352
which extends through an aperture
354
formed in the base
320
. The second connector alignment apparatus
54
is loosely connected to an end surface
356
of the frame
20
. A fastener
358
is configured to extend through an oversized central opening
360
formed in housing
340
. Posts
342
at opposite ends of the housing
340
are located within apertures
362
formed in the surface
356
of the frame
20
. Housing
340
is therefore not rigidly coupled to frame
20
and can float slightly due to the oversized apertures
362
and the oversized aperture
360
.
During installation of the footboard
28
on to the frame
20
, initial alignment is provided by posts
58
on frame
20
extending into the apertures
56
formed in the footboard
28
. As the footboard
28
moves downwardly over the posts
58
, the posts
322
on first connector alignment apparatus
52
enter the apertures
344
in the second connector alignment apparatus
54
. Tapered surfaces
324
on posts
22
and tapered surfaces
346
of apertures
344
facilitate insertion of the posts
322
into the apertures
344
. Since the housing
340
of second connector alignment apparatus
54
can float on the frame
20
, the housing
340
moves into proper alignment with the first connector alignment apparatus
52
as the footboard
28
is installed. This ensures proper alignment between connectors
62
and
64
. Typically, connectors
62
and
64
include further alignment posts
313
and apertures
315
, respectively, which mate to make sure that each of the terminals
312
line up with the socket contacts
318
. Therefore, the connector alignment apparatus of the present invention includes a combination of posts
58
on the frame
20
which mate with aperture
56
on the footboard
28
, posts
322
on the first connector alignment apparatus
52
which mate with apertures
344
on the second connector alignment apparatus
54
, and posts
313
on connectors
62
which mate with apertures
315
on the connectors
64
to provide further alignment.
Although the invention has been described in detail with reference to certain illustrated embodiments, variations and modifications exist within the scope and spirit of the invention as described and as defined in the following claims.
Claims
- 1. An apparatus for detecting a position of a body on a support surface of a bed, the apparatus comprising:at least one first sensor coupled to the bed, the at least one first sensor having an output signal which is variable in response to changes in a weight applied to the support surface; at least one second sensor located adjacent the support surface, the at least one second sensor having an output signal which is variable in response to changes in the position of the body on the support surface; and a controller having inputs configured to receive the output signals from the first and second sensors, the controller being configured to monitor the output signals, to provide an indication of changes in the position of the body relative to the support surface, and to provide an indication if the body exits the support surface.
- 2. The apparatus of claim 1, wherein the first and second sensors are different types of sensors.
- 3. The apparatus of claim 1, wherein the at least one second sensor is a resistive pressure sensor.
- 4. The apparatus of claim 1, wherein the at least one second sensor is a capacitance sensor.
- 5. The apparatus of claim 1, wherein the at least one second sensor is a piezoelectric sensor.
- 6. The apparatus of claim 1, wherein the at least one first sensor is a load cell.
- 7. The apparatus of claim 6, wherein the bed includes a base frame and a weigh frame, the weigh frame being configured to support the support surface of the bed, and wherein the at least one first sensor includes a plurality of load cells configured to couple the weigh frame to the base frame, each of the plurality of load cells being electrically coupled to the controller.
- 8. The apparatus of claim 1, wherein a plurality of second sensors are located adjacent the support surface, each of the plurality of second sensors being electrically coupled to the controller.
- 9. The apparatus of claim 1, wherein the support surface of the bed includes a deck and a mattress located on the deck, the at least one second sensor being coupled to the mattress.
- 10. The apparatus of claim 9, wherein the at least one second sensor is located within an interior region of the mattress.
- 11. The apparatus of claim 1, wherein the support surface of the bed includes a deck and a mattress located on the deck, the at least one second sensor being coupled to the deck.
- 12. The apparatus of claim 11, wherein the deck includes a head deck section, a seat deck section, a thigh deck section, and a leg deck section, and the second sensors include at least one head sensor coupled to the head deck section, at least one seat sensor coupled to the seat deck section, and at least one thigh sensor coupled to the thigh deck section.
- 13. The apparatus of claim 12, wherein two spaced apart thigh sensors are coupled to the thigh deck section.
- 14. The apparatus of claim 12, wherein the head sensor is an elongated strip which extends in a direction parallel to a longitudinal axis of the deck, the head sensor being located at a center portion of the head deck section.
- 15. The apparatus of claim 14, wherein two elongated thigh sensors are coupled to the thigh deck section, the elongated thigh sensors extending in a direction parallel to the longitudinal axis of the deck.
- 16. The apparatus of claim 15, wherein the seat sensor is an elongated strip which is configured to extend in a direction transverse to the longitudinal axis of the deck.
- 17. The apparatus of claim 12, wherein the second sensors further include at least one leg sensor coupled to the leg deck section.
- 18. The apparatus of claim 12, further comprising an alarm coupled to the controller, the controller having a first mode of operation in which the alarm is activated by the controller only when the at least one first sensor detects that the body has exited the bed, a second mode of operation in which the alarm is activated by the controller when the head, seat and thigh sensors detect that the body has moved away from a central portion of the support surface, and a third mode of operation in which the alarm is activated by the controller when the head sensor detects that the body has moved away from a central portion of the head deck section.
- 19. The apparatus of claim 1, further comprising an alarm coupled to the controller, the controller having a first mode of operation in which the alarm is activated by the controller only when the at least one first sensor detects that the body has exited the bed, and a second mode of operation in which the alarm is activated by the controller when the at least one second sensor detects that the body has moved away from a central portion of the support surface.
- 20. The apparatus of claim 19, wherein the controller includes a third mode of operation in which the alarm is activated by the controller when the at least one second sensor detects that the body has moved away from a central portion of a head section of the deck.
- 21. The apparatus of claim 20, further comprising first, second, and third mode indicator lights located on the bed which correspond to the first, second, and third modes of operation of the controller, respectively, the controller being coupled to the first, second, and third mode indicator lights.
- 22. The apparatus of claim 21, wherein the controller is configured to illuminate the first mode indicator light when the controller is in the first operation mode, to illuminate the first and second mode indicator lights when the controller is in the second operation mode, and to illuminate the first, second, and third mode indicator lights when the controller is in the third operation mode.
- 23. The apparatus of claim 19, further comprising a control panel coupled to the controller to permit a caregiver to select between the first and second modes of operation.
- 24. The apparatus of claim 23, wherein the control panel is coupled to a siderail of the bed.
- 25. The apparatus of claim 23, wherein the control panel is located on a pendant coupled to the controller.
- 26. The apparatus of claim 23, wherein the control panel is coupled to the controller by a remote control transmitter.
- 27. The apparatus of claim 23, wherein the control panel includes an actuator to permit a caregiver to adjust a volume of the alarm.
- 28. The apparatus of claim 23, wherein the control panel includes a key button and a separate mode button, the controller permitting the caregiver to change the mode of operation by pressing the mode button only when the key button is also pressed.
- 29. The apparatus of claim 28, wherein the control panel also includes a volume control button, the controller being configured to permit the caregiver to adjust the volume of the alarm using the volume control button only when the key button is also pressed.
- 30. The apparatus of claim 23, further comprising at least two indicator lights coupled to the control panel to provide a visual indication of the mode of operation of the controller.
- 31. The apparatus of claim 1, further comprising an alarm coupled to the controller, the controller being configured to activate the alarm when the patient is out of a predetermined position on the support surface, the controller being configured to detect when the body moves back into the predetermined position on the support surface, and the controller automatically deactivating the alarm upon detection of the body moving back into the predetermined position on the support surface.
- 32. The apparatus of claim 1, wherein the controller is configured to monitor movement of the body on the support surface, the controller being configured to generate an output signal if a predetermined amount of movement of the body is not detected within a predetermined period of time.
- 33. The apparatus of claim 1, wherein the controller includes an output coupled to a communication port to provide a nurse call alarm upon detection of the body moving out of a predetermined position on the support surface of the bed.
- 34. The apparatus of claim 33, further comprising a nurse call clear actuator coupled to the bed, the nurse call clear actuator being configured to clear the nurse call alarm.
- 35. The apparatus of claim 1, wherein the controller includes an output coupled to a communication network, the controller being configured to transmit a data to a nurse station over the communication network, the data including information related to at least one of a patient weight, a patient position on the support surface, a bed exit indicator, a mode of operation of a patient position detection apparatus, a brake not set indicator, and a bed not down indicator.
- 36. The apparatus of claim 1, further comprising an alarm coupled to the controller, and a control panel coupled to the controller, the control panel including an actuator to permit a tone of the alarm to be selected from a plurality of different tones.
- 37. The apparatus of claim 1, wherein the controller is configured to turn on a room light upon detection of the body moving out of a predetermined position on the support surface.
- 38. An apparatus for detecting a position of a body on a support surface of a bed, the apparatus comprising:at least one sensor coupled to the bed, the at least one sensor having an output signal which is variable in response to changes to in the position of the body on the support surface; an alarm; a controller having at least one input configured to received the output signal from the at least one sensor and an output coupled to the alarm, the controller having at least two different modes of operation to monitor the position of the body on the support surface and generate an alarm signal to activate the alarm if predetermined conditions are met; and a control panel coupled to the controller, the control panel including a key button and a separate mode button to permit a caregiver to change the mode of operation of the controller, the controller being configured to permit a caregiver to adjust the mode of operation by pressing the mode button only when the key button is also pressed.
- 39. The apparatus of claim 38, wherein the control panel is coupled to a siderail of the bed.
- 40. The apparatus of claim 38, wherein the control panel is located on a pendant coupled to the controller.
- 41. The apparatus of claim 38, wherein the control panel is coupled to the controller by a remote control transmitter.
- 42. The apparatus of claim 38, wherein the control panel also includes an alarm volume control button, the controller being configured to permit the caregiver to adjust the volume of the alarm using the volume control button only when the key button is also pressed.
- 43. The apparatus of claim 38, wherein the control panel includes an actuator to permit a tone of the alarm to be selected from a plurality of different tones.
- 44. The apparatus of claim 38, wherein the controller is configured to turn on a room light wherein the alarm signal is generated.
- 45. The apparatus of claim 38, wherein the controller has first, second and third different modes of operation, the alarm being activated by the controller when different levels of patient movement on the support surface are detected for the first, second and third modes of operation.
- 46. The apparatus of claim 45, further comprising first, second, and third mode indicator lights located on the control panel which correspond to the first, second, and third modes of operation of the controller, respectively, the controller being coupled to the first, second, and third mode indicator lights.
- 47. The apparatus of claim 46, wherein the controller is configured to illuminate the first mode indicator light when the controller is in the first operation mode, to illuminate the first and second mode indicator lights when the controller is in the second operation mode, and to illuminate the first, second, and third mode indicator lights when the controller is in the third operation mode.
- 48. An apparatus for supporting a patient, the apparatus comprising:a frame, a mattress supported by the frame, and a patient position detection system including an alarm and at least one sensor configured to detect a position of the patient relative to the mattress, the patient position detection system having at least three modes of operation, a first mode of operation resulting in the alarm being activated when the patient moves toward exiting the mattress by a first amount, a second mode of operation resulting in the alarm being activated when the patient moves toward exiting the mattress by a second amount greater than the first amount, and a third mode of operation resulting in the alarm being activated when the patient exits the mattress.
- 49. The apparatus of claim 48, wherein the patient position detection system includes at least one first sensor coupled to the frame, the at least one first sensor having an output signal which is variable in response to changes in a weight applied to the mattress, at least one second sensor located adjacent the mattress, the at least one second sensor having an output signal which is variable in response to changes in the position of the patient on the mattress, and a controller having inputs configured to receive the output signals from the first and second first sensors, the controller being configured to monitor the output signals, to provide an indication of changes in the position of the patient relative to the mattress, and to activate the alarm in the first, second and third modes of operation.
- 50. The apparatus of claim 49, wherein the at least one first sensor is a load cell and the at least one second sensor is one of a resistive pressure sensor, a capacitance sensor, and a piezoelectric sensor.
- 51. The apparatus of claim 48, further comprising a deck coupled to the frame, the mattress being located on the deck, the deck including a head deck section, a seat deck section, a thigh deck section, and a leg deck section, and wherein at least one head sensor is coupled to the head deck section, at least one seat sensor is coupled to the seat deck section, and at least one thigh sensor is coupled to the thigh deck section.
- 52. The apparatus of claim 48, wherein the patient position detection system includes controller coupled to the at least one sensor and first, second, and third mode indicator lights which correspond to the first, second, and third modes of operation of the patient position detection system, respectively, the controller being coupled to the first, second, and third mode indicator lights.
- 53. The apparatus of claim 48, wherein the patient position detection system includes controller coupled to the at least one sensor and further comprising a control panel coupled to the controller to permit a caregiver to select between the first, second and third modes of operation.
- 54. The apparatus of claim 53, wherein the control panel includes an actuator to permit the caregiver to adjust a volume of the alarm.
- 55. The apparatus of claim 53, wherein the control panel includes a key button and a separate mode button, the controller permitting the caregiver to change the mode of operation by pressing the mode button only when the key button is also pressed.
- 56. The apparatus of claim 53, wherein the control panel includes a key button and a separate a volume control button to permit the caregiver to adjust a volume of the alarm, the controller being configured to permit the caregiver to adjust the volume of the alarm using the volume control button only when the key button is also pressed.
- 57. The apparatus of claim 48, wherein the patient position detection system is coupled to a communication port to provide a nurse call alarm to a remote location when the alarm is activated.
- 58. An apparatus for supporting a patient, the apparatus comprising:a frame, a mattress supported by the frame, and a patient position detection system including an alarm and at least one sensor configured to detect a position of the patient relative to the mattress, the patient position detection system having at least three modes of operation, a first mode of operation resulting in the alarm being activated when the patient moves away from a central region of the mattress by a first amount, a second mode of operation resulting in the alarm being activated when the patient moves away from the central region of the mattress by a second amount greater than the first amount, and a third mode of operation resulting in the alarm being activated when the patient exits the mattress.
- 59. The apparatus of claim 58, wherein the patient position detection system includes at least one first sensor coupled to the frame, the at least one first sensor having an output signal which is variable in response to changes in a weight applied to the mattress, at least one second sensor located adjacent the mattress, the at least one second sensor having an output signal which is variable in response to changes in the position of the patient on the mattress, and a controller having inputs configured to receive the output signals from the first and second first sensors, the controller being configured to monitor the output signals, to provide an indication of changes in the position of the patient relative to the mattress, and to activate the alarm in the first, second and third modes of operation.
- 60. The apparatus of claim 59, wherein the at least one first sensor is a load cell and the at least one second sensor is one of a resistive pressure sensor, a capacitance sensor, and a piezoelectric sensor.
- 61. The apparatus of claim 58, further comprising a deck coupled to the frame, the mattress being located on the deck, the deck including a head deck section, a seat deck section, a thigh deck section, and a leg deck section, and wherein at least one head sensor is coupled to the head deck section, at least one seat sensor is coupled to the seat deck section, and at least one thigh sensor is coupled to the thigh deck section.
- 62. The apparatus of claim 58, wherein the patient position detection system includes controller coupled to the at least one sensor and first, second, and third mode indicator lights which correspond to the first, second, and third modes of operation of the patient position detection system, respectively, the controller being coupled to the first, second, and third mode indicator lights.
- 63. The apparatus of claim 58, wherein the patient position detection system includes controller coupled to the at least one sensor and further comprising a control panel coupled to the controller to permit a caregiver to select between the first, second and third modes of operation.
- 64. The apparatus of claim 63, wherein the control panel includes an actuator to permit the caregiver to adjust a volume of the alarm.
- 65. The apparatus of claim 63, wherein the control panel includes a key button and a separate mode button, the controller permitting the caregiver to change the mode of operation by pressing the mode button only when the key button is also pressed.
- 66. The apparatus of claim 63, wherein the control panel includes a key button and a separate a volume control button to permit the caregiver to adjust a volume of the alarm, the controller being configured to permit the caregiver to adjust the volume of the alarm using the volume control button only when the key button is also pressed.
- 67. The apparatus of claim 58, wherein the patient position detection system is coupled to a communication port to provide a nurse call alarm to a remote location when the alarm is activated.
US Referenced Citations (17)