Abstrict A control assembly for an adjustable bed includes push-button devices
for selectively engaging associated clutches. A single device may
be actuated to engage a single clutch. Alternatively, a plurality
of devices may be actuated simultaneously to engage a plurality
of clutches. As any one or more buttons is pushed, a slide bar sequentially
releases all devices and latches those for which buttons are pushed
to the clutch-actuating position. A single crank provides torque
for a transmission thereby clutched to lift screws.
Claims What is claimed is:
1. An adjustable bed including a relatively fixed frame, a movable
frame, a mattress support structure, head and foot lift mechanisms
for raising and lowering the head and foot ends respectively of
said movable frame, back and knee lift mechanisms for raising and
lowering the back and knee sections respectively of said mattress
support structure, transmission means engageable for directing torque
to said lift mechanisms for actuation thereof, said transmission
means including head, foot, back and knee lift screws respectively
in driving relationship with said lift mechanisms, a gear train
including a drive gear, and head, foot, back and knee driven gears
in meshing relationship with said drive gear, head, foot, back and
knee clutches selectively engageable for respectively establishing
engagement of said driven gears with said lift screws, a manual
crank engaged with said drive gear for rotation of said drive train,
means associated with each of the lift mechanisms and its transmission
means for stopping movement of the said lift mechanism when the
limits of its travel are reached while permitting continued movement
of another lift mechanism, manual control means for selectively
engaging said transmission means with any number of said lift mechanisms
for individual or simultaneous actuation thereof, and means for
locking said control means in engaged position.
2. Apparatus comprising a housing, a plate slidable in said housing
between first and second positions, first biasing means biasing
said plate towards its first position, independent means for sliding
said plate to its second position in opposition to said biasing
means, said plate defining a plurality of cam surfaces and slots,
a plurality of selecting devices each associated with a cam surface
and slot, each device being movable between a first position and
a second position latched in an associated slot, and second biasing
means biasing each device toward its first position, said plate
and devices being constructed and arranged such that as any number
of devices are moved to their second position said plate is cammed
to its second position thereby unlatching all devices, said plate
then being biased to its first position thereby latching those devices
in their second position.
3. The invention of claim 2 further comprising a plurality of
lift screws, a gear train adapted for transmitting torque to said
lift screws, and a plurality of clutches each engageable for clutching
an associated lift screw to said gear train, each clutch being related
to an associated device such that movement of said device to its
first position releases said clutch for disengagement and movement
of said device to its second position engages said clutch.
4. The invention of claim 3 one of said devices being related
to two of said clutches such that movement of said one device to
its first position releases said two clutches for disengagement
and movement of said one device to its second position engages said
two clutches.
5. The invention of claim 2 3 or 4 each device being manually
movable by a push button to its second position.
6. An adjustable bed comprising:
(a) a relatively fixed frame,
(b) a movable frame,
(c) a mattress support structure,
(d) head and foot lift mechanisms for raising and lowering the
head and foot ends respectively of said movable frame,
(e) back and knee lift mechanisms for raising and lowering the
back and knee sections respectively of said mattress support structure,
(f) transmission means comprising head, foot, back and knee lift
screws respectively in driving relationship with said lift mechanisms,
a gear train including aa drive gear, and head, foot, back and knee
driven gears in meshing relationship with said drive gear, head,
foot, back and knee clutches selectively engageable for respectively
establishing engagement of said driven gears with said lift screws,
a crank engaged with said drive gear, and
(g) control means for selectively engaging said transmission means
with any number of said lift mechanisms for simultaneous actuation
thereof, said control means comprising manually actuated head, foot,
back and knee selecting devices for selectively effecting engagement
of any number of said clutches, actuation of any of said devices
sequentially effecting release of all clutches and engagement of
those clutches associated with the devices actuated, a slide bar
movable between first and second positions, means biasing said slide
bar toward its first position, said slide bar defining a plurality
of cam surfaces and detent slots, each device including a push button,
a pin, a rod, and a member coupling said rod with an associated
clutch, each device being movable from a first position in which
said pin is contiguous to an associated cam surface and an associated
clutch is released to a second position in which said pin is latched
in an associated detent slot and said associated clutch is engaged,
and means biasing each device toward its first position, said slide
bar and device being constructed and arranged such that as said
push button moves toward its second position said pin cams said
slide bar toward its second position and said member engages said
associated clutch.
7. An adjustable bed comprising:
(a) a relatively fixed frame,
(b) a movable frame,
(c) a mattress support structure,
(d) head and foot lift mechanisms for raising and lowering the
head and foot ends respectively of said movable frame,
(e) back and knee lift mechanisms for raising and lowering the
back and knee sections respectively of said mattress support structure,
(f) transmission means comprising head, foot, back and knee lift
screws respectively in driving relationship with said lift mechanisms,
a gear train including a drive gear, and head, foot, back and knee
driven gears in meshing relationship with said drive gear, head,
foot, back and knee clutches selectively engageable for respectively
establishing engagement of said driven gears with said lift screws,
and a crank engaged with said drive gear, and
(g) control means for selectively engaging said transmission means
with any number of said lift mechanisms for simultaneous activation
thereof, said control means comprising manually actuated head, foot,
back and knee selecting devices for selectively effecting engagement
of any number of said clutches, a manually actuated bed selecting
device for simultaneously effecting engagement of said head and
foot clutches, actuation of any of said devices sequentially effects
release of all clutches and engagement of those clutches associated
with the devices actuated, a slide bar movable between first and
second positions, means biasing said slide bar toward its first
position, said slide bar defining a plurality of cam surfaces and
detent slots, each device including a push button, a pin, a rod,
and a member coupling said rod with an associated clutch, each device
being movable from a first position in which said pin is continguous
to an associated cam surface and an associated clutch is released
to a second position in which said pin is latched in an associated
detent slot and said associated clutch is engaged, and means biasing
each device toward its first position, said slide bar and device
being constructed and arranged such that as said push button moves
toward its second position said pin cams said slide bar toward its
second position and said member engages said associated clutch.
8. The invention of claim 7 said bed selecting device including
an arm in driving relationship with the members of said head and
foot selecting devices to thereby engage said head and foot clutches
when the button of said bed selecting device is pushed.
9. An adjustable bed including a relatively fixed frame, a movable
frame, a mattress support structure, head and foot lift mechanisms
for raising and lowering the head and foot ends respectively of
said movable frame, back and knee lift mechanisms for raising and
lowering the back and knee sections respectively of said mattress
support structure, transmission means engageable for directing torque
to said lift mechanisms for actuation thereof, means associated
with each of the lift mechanisms and its transmission means for
stopping movement of the said lift mechanism when the limits of
its travel are reached while permitting continued movement of another
lift mechanism and control means for selectively engaging said transmission
means with any number of said lift mechanisms for simultaneous action
thereof, said control means including manually actuated head, foot,
back and knee selecting devices constructed and arranged such that
actuation of any of said devices sequentially effects disengagement
of said transmission means with all lift mechanisms and locking
engagement with those lift mechanisms associated with the devices
actuated.
10. The invention of claim 9 said control means also including
a manually actuated bed selecting device constructed and arranged
such that actuation thereof sequentially effects disengagement of
said transmission means with all lift mechanisms and locking engagement
simultaneously with said head and foot lift mechanisms.
Description BACKGROUND OF THE INVENTION
This invention relates generally to controlling the movement of
adjustable beds. More particularly, it relates to an improved assembly
for adjusting the various positions of a hospital bed.
In a hospital environment, it is necessary for a bed to be provided
with multiple functional capabilities. It must be capable of vertical
movement so that it may be raised or lowered to a desired position.
It must be capable of tilting so that it may be placed in either
the Trendelenburg position or the reverse Trendelenburg position.
Further, the head and knee sections of the mattress support structure
must be capable of individual adjustment to provide for patient
comfort.
In the past, a typical assembly for controlling the various movements
of a hospital bed required the selection of one function at a time.
If it were desired, for example, to lower the back and knee sections,
as well as move the bed into Trendelenburg, an attendant would first
engage the back section and crank it to the desired position, then
engage the knee section and crank it to the desired position, and
finally engage the head section and crank it so as to tilt the movable
frame.
There remains a need in the art to provide a simple, inexpensive,
efficient, long-wearing assembly for controlling the various movements
of a hospital bed, which assembly allows the selection of any one
or combination of the various functional modes. The assembly should
engage each function selected, and should be capable of actuating
all of them simultaneously upon the rotation of a single crank.
Since all functional movements do not require the same amount of
cranking, the assembly should be capable of disengaging automatically
whichever functions reach their limit of travel, while at the same
time subjecting the remaining functions to further cranking action.
The assembly should preferably be located at or adjacent the control
station at the foot of the bed so as to be easily operable by an
attendant.
SUMMARY OF THE INVENTION
The primary object of this invention is to meet the needs noted
above. To that end, there is provided an assembly which includes
push-button devices for engaging the clutches of a transmission
to thereby select one or more of the various functional modes necessary
for hospital bed. After selection, a single crank drives lift screws
and slip nuts, which in turn drive link mechanisms so as to move
the various sections of the bed to their desired positions. A slide
bar latches the push-button devices in order to hold associated
clutches in their engaged positions. Pushing any button or combination
of buttons releases whichever ones may previously have been pushed.
The result is a simple, inexpensive, efficient long-wearing assembly
which provides the capability of selecting one or a combination
of functional modes for the adjustment of a hospital bed and for
simultaneous actuation of all modes selected.
BRIEF DESCRIPTION OF THE DRAWINGS
The objects and advantages of this invention will become apparent
to those skilled in the art upon careful consideration of the specification
herein, including the drawings, wherein:
FIG. 1 is an elevational view of an adjustable hospital bed showing
the arrangement of the various lift mechanisms;
FIG. 2 is a partial plan view of the upper frame of the bed, cut
away to show details of the lift mechanisms and transmission;
FIG. 3 is a plan view, partially in section, showing the control
assembly and additional details of the transmission;
FIG. 4 is an elevational view showing details of the push-button
devices; and
FIG. 5 is a sectional view taken along the line 5--5 of FIG. 4
showing additional details of the push-button devices.
While this invention is susceptible of embodiment in many different
forms, there is shown in the drawings and herein will be described
in detail a preferred embodiment. It should be understood that the
present disclosure is considered to be an exemplification of the
principles of the invention, and is not intended to limit the invention
to this embodiment.
DESCRIPTION OF A PREFERRED EMBODIMENT
Referring now to the drawings in greater detail, There is shown
generally a typical hospital bed 10. Bed 10 includes a relatively
fixed lower frame 12 and a movable upper frame 14 having a head
end 16 and a foot end 18. Bed 10 also includes an articulated mattress
support structure 20 having a back section 22 and a knee section
24. Suitable guard rails 26 are provided at the sides of bed 10.
A head lift mechanism 28 is provided for raising and lowering head
end 16 of upper frame 14. Similarly, a foot lift mechanism 30 is
provided for raising and lowering foot end 18 of upper frame 14.
A back lift mechanism 32 and a knee lift mechanism 34 are provided
for raising and lowering back section 22 and knee section 24 of
structure 20 respectively.
Knee lift mechanism 34 is driven by a slip nut 36 threaded on a
lift screw 38 for axial movement between limit stops 40 and 42.
Head lift mechanism 28 is driven by a slip nut 44 threaded on a
lift screw 46 for axial movement between limit stops 48 and 50.
Foot lift mechanism 30 is driven by a slip nut 52 threaded on a
lift screw 54 for axial movement between limit stops 56 and 58.
Similarly, back lift mechanism 32 is driven by a slip nut 60 threaded
on a lift screw 62 for axial movement between limit stops 64 and
66. The slip nuts, lift screws and limit stops form part of a transmission
68 details of which are disclosed in co-pending U.S. application
Ser. No. 211541 12/1/80 Lester W. Werner entitled Brake Mechanism
for an adjustable Hospital bed. (Now aband.) provided for selectively
rotating lift screws 38 46 54 and 62 so as to drive slip nuts
36 44 52 and 60 as desired.
Transmission 68 also includes a plurality of clutches 70 72 74
and 76 each engaged with an associated lift screw 38 46 54 and
62. Details of these clutches are disclosed in co-pending U.S. application
Ser. No. 211541 filed 12/1/80.
Transmission 68 further includes a gear train 78 having a drive
gear 80 and driven gears 82 84 86 and 88. A single crank 90 is
engaged with gear 80 for providing the torque to drive gear train
78. Selective engagement of clutches 70 72 74 and 76 respectively
locks lift screws 38 46 54 and 62 to gears 82 84 86 and 88.
It will be apparent that selective engagement of one or more clutches
will result in one or more lift screws being rotated by crank 90
as desired.
Selective engagement of the clutches is provided by a control assembly
92. Assembly 92 includes a housing 94 secured to upper frame 14.
A slide bar or plate 96 is supported by housing 94 for horizontal
sliding movement as shown in FIG. 3. A spring 98 biases slide bar
96 to the left. A cancel lever 100 is provided to allow manual movement
of slide bar 96 to the right against the biasing force of spring
98. Slide bar 96 defines a plurality of spaced cam or ramp surfaces
102. Associated with these cam surfaces are a plurality of detent
slots 104.
Assembly 92 also includes a knee push-button device 106 a head
push-button device 108 a bed push-button device 110 a foot push-button
device 112 and a back push-button device 114. Each device includes
a pin 116 and a rod 118. A tubular member 120 is slidably received
on each rod 118 except the one associated with bed device 110. A
spring 122 biases each device outwardly, or downwardly as shown
in FIG. 3.
A shaft 124 extends through each clutch in telescoping relationship
with an associated member 120. A load spring 126 is coiled around
each shaft 124 between each clutch and member 120.
An arm 128 is secured to the rod 118 associated with bed device
110. This arm extends into contact with surfaces 130 defined by
the rods 120 associated with head device 108 and foot device 112.
As shown in FIG. 3 the devices are in their first, disengaged
position. Spring 98 biases slide bar 96 leftwardly such that pins
116 are substantially in contact with cam surfaces 102. In this
position, none of clutches 70 72 74 or 76 is engaged. Rotation
of crank 90 drives gear train 78 but does not drive any of lift
screws 38 46 54 or 62.
If it is desired to raise or lower knee section 24 of mattress
support structure 20 for example, knee button 106 is pushed inwardly,
or upwardly as shown in FIG. 3. Its pin 116 rides up surface 102
thereby camming slide bar 96 to the right. At the same time, its
rod 118 and member 120 compress load spring 126 thereby engaging
knee clutch 70. When pin 116 reaches the top of surface 102 spring
98 pulls slide bar 96 leftwardly such that pin 116 is latched in
detent slot 104. Thus, clutch 70 remains engaged. Rotation of crank
90 now turns knee lift screw 38.
It should be apparent that any number of buttons may be pushed
simultaneously to selectively engage the associated clutches, whereupon
rotation of crank 90 will turn the associated lift screws simultaneously.
As disclosed in the aforementioned U.S. application Ser. No. 211541
filed 12/1/80 when an associated slip nut reaches the limit of
its travel, it slips while the remaining ones continue their travel.
For convenience, bed device 110 is provided for simultaneous engagement
of head clutch 72 and foot clutch 74. By pushing bed button 110
arm 128 is moved so as to drive the two associated members 120
thereby compressing both of the associated load springs 126 to engage
clutches 72 and 74. In this manner, head and foot lift screws 46
and 54 may be actuated simultaneously to raise or lower upper frame
14 without tilting it.
As noted, pushing any one or combination of the buttons shifts
slide bar 96 to the right, at which time the remaining buttons are
released from their associated detent slots to thereby unlatch the
associated devices. Cancel lever 100 is provided to allow an attendant
to shift slide bar 96 against the biasing force of spring 98 to
release all of the buttons, if desired.
It should be apparent to those skilled in the art that there is
disclosed herein an improved control assembly for selection of the
various functional modes of an adjustable bed. The assembly is so
constructed and arranged that either one or a plurality of functional
modes may be selected. A single crank drives the appropriate lift
screws, depending upon which functional mode or modes have been
selected. The control assembly and cranking structure are simple,
inexpensive, efficient and long-wearing and may be serviced easily
in the field.
In a preferred form of the invention, the control assembly is provided
with a plurality of push-button devices for selection of the various
functional modes. It should be obvious however, that devices with
other than push buttons may be provided for effecting such selection.
Further, although a single crank is provided in the preferred form
of the invention for driving the selected lift screws, obviously
other suitable drive means may be provided.
It is not intend that the present invention be restricted in its
application to the hospital bed shown herein by way of example.
It is contemplated that the invention will be utilized in a wide
variety of applications in which it is desirable to control the
various modes of a frame having a plurality of functional capabilities.
It should be understood that while a preferred embodiment of the
invention has been shown and described, this is to be considered
as illustrative and may be modified by those skilled in the art.
It is intended that the claims herein cover all such modifications
as may fall within the spirit and scope of the invention. |