Title: Electronic scale assembly having incorporated spreader arm
Abstract: An electronic scale/spreader arm assembly for use with an apparatus includes an axial force transducer, such as a load cell, that is attachable to the apparatus. A spreader bar is configured to receive a support wherein the spreader bar and the load cell are interconnected such that the load cell is pivotally attached to the apparatus and the spreader arm is pivotally attached to the support while the spreader arm and the load cell are attached to one another such that non-axial loads imparted to the spreader arm will not be transmitted to the axial force transducer.
Patent Number: 7,022,921 Issued on 04/04/2006 to Petrotto
| Inventors:
|
Petrotto; Gerald J. (Williamsville, NY)
|
| Assignee:
|
SR Instruments, Inc. (Tonawanda, NY)
|
| Appl. No.:
|
446607 |
| Filed:
|
May 28, 2003 |
| Current U.S. Class: |
177/144; 177/147 |
| Current Intern'l Class: |
G01G 19/52 (20060101); G01G 19/14 (20060101) |
| Field of Search: |
177/126,144,147,229,245
|
References Cited [Referenced By]
U.S. Patent Documents
Primary Examiner: Gibson; Randy W.
Attorney, Agent or Firm: Bilinski; Peter J.
Claims
We claim:
1. A scale assembly including:
an axial load transducer having a primary load axis extending through the center
of said transducer, said axial force transducer being pivotally attached to a support
member; and
a load supporting member including means on opposing sides thereof for supporting
a load wherein said load supporting member is pivotally attached to said axial
force transducer along at least one pivot axis that is orthogonal to the primary
load axis and extends substantially through the center of said axial force transducer
wherein components of said supported load other than axial loads transmitted along
said primary load axis are not transmitted to said axial force transducer.
2. A scale assembly as recited in claim 1, wherein said axial force transducer
is disposed within an inner supporting member and said load supporting member is
defined by a housing sized for retaining each of said inner supporting member and
said axial force transducer.
3. A scale assembly as recited in claim 1, wherein said scale assembly is an
electronic scale assembly wherein the output of said axial force transducer is displayed.
4. A scale assembly as recited in claim 1, including means for detecting when
said load supporting member has pivoted beyond a predetermined angular position.
5. A scale assembly as recited in claim 1, wherein said assembly is used in a
patient lifting apparatus.
6. A patient lift/transfer apparatus comprising:
a lift mechanism for lifting a patient;
a load supporting member attached to said lift mechanism; and
an electronic scale assembly including an axial force transducer having a primary
load axis extending through the center of said transducer, said axial force transducer
being pivotally attached to said lift mechanism and means for pivotally attaching
said load supporting member to said axial force transducer about at least one pivot
axis permitting said load supporting member to freely pivot about said at least
one pivot axis, while said axial force transducer is maintained in said axial orientation,
said at least one pivot axis being orthogonal to said primary load axis and extending
substantially through the center of said axial force transducer.
7. An apparatus as recited in claim 6, wherein said load supporting member is
substantially coplanar with said axial force transducer in a plane that is substantially
orthogonal with said primary force axis of said axial force transducer.
8. An apparatus as recited in claim 6, wherein said axial force transducer and
said load supporting member are pivotally attached to said lift mechanism.
9. An apparatus as recited in claim 8, including at least one sensor for determining
when said lift mechanism has caused said axial force transducer to have pivoted
beyond a predetermined position.
10. A method for isolating non-axial loads from an axial load transducer in an
apparatus, said method including the steps of:
mounting an axial force transducer to said apparatus, said force transducer having
a primary load axis extending through the center of said transducer;
attaching a load supporting member to said axial force transducer, said load
supporting member being pivotably attached to said axial force transducer through
at least one pivot axis extending substantially through the center of said transducer
and in a plane orthogonal to the primary load axis; and
supporting a load on said load supporting member wherein non-axial loads are
not transmitted to said axial force transducer.
11. A method as recited in claim 10, including the step of disposing said load
supporting member substantially coplanar with the plane that is orthogonal to said
primary load axis of said axial force transducer.
12. A method as recited in claim 10, including the step of detecting when said
load supporting member has pivoted beyond a predetermined position.
13. A method as recited in claim 10, including the step of pivotally mounting
said axial force transducer to said apparatus.
Description
FIELD OF THE INVENTION
This invention relates to the field of weight measurement, and more particularly
to an electronic scale assembly that is directly integrated or can be added to
an apparatus, such as, for example, a patient transfer device.
BACKGROUND OF THE INVENTION
Portable apparatus, such as, for example, patient lifting devices are well
known in the medical field for transferring patients between varying locations,
such as, for example, between a bed and a gurney or between a test station and
a wheelchair. These devices commonly include a base section having an attached
hydraulic or other form of lifting mechanism. This lifting mechanism typically
includes an boom arm having an articulating end that is attached by means of a
spreader arm, bar or other load supporting member to a body sling, wheelchair,
or similar lifting patient support. The spreader arm attempts to evenly distribute
the weight of the patient support and includes receiving means on opposing ends
to which straps or other connecting means from the patient support are attached.
Stationary types of the above devices, such as ceiling mounted versions, are also
commonly known in the field.
There are several manufacturers of various apparatuses, such as the above noted
patient lifting devices and patient transfer devices that now each use an electronic
scale as an accessory to their lifts. These electronic scales are discrete assemblies
that separately incorporate a tensile load cell or similar axial force transducer
whose output can be converted for readout onto a display. Though some success has
been achieved in having an electronic scale with a patient lifting device, there
are a number of disadvantages in using "off the shelf" electronic scales in conjunction therewith.
A first noted disadvantage in incorporating so-called "off the shelf" electronic
scale assemblies is that the overall lifting height of the lifting device is decreased
because the scale accessory is typically attached between the lift boom and the
spreader bar or other load supporting member. This attachment decreases the overall
effectiveness of the patient lifting device and also increases the overall lifting
height and the angle of the lift boom which may also adversely affect the center
of gravity of the device.
A second disadvantage created in using an attached electronic scale is that inaccuracies
are induced into the scale because the scale is restricted from movement in at
least one or more directions. When electronic scales having a tensile load cell
or similar axial force transducer design are not permitted to hang freely from
the lift boom, a side load or torque is created, thereby skewing the pure tensile
load that is created by the patient. As a result, indirect loads are transmitted
to the electronic scale assembly and inaccurate readings are displayed.
Yet a third disadvantage is that there are other inaccuracies that can be induced
into the electronic scale when the scale is not oriented vertically. That is to
say, if the line of force through a load cell is not vertical, an error is produced
that is proportional to the horizontal force component. The latter problem is also
produced when attempting to incorporate an electronic scale into a spreader bar
or other load supporting member.
There are additional problems or disadvantages which arise when attempting
to incorporate an electronic scale into a spreader bar. For example, if the spreader
bar travel is restricted, side loads will be introduced. In addition and if the
spreader bar permits the patient's center of gravity to travel outside of the support
structure of the patient lifting device, the device could become unstable wherein
possible serious injury could result.
SUMMARY OF THE INVENTION
It is therefore a primary object of the present invention to overcome the above-noted
deficiencies of the prior art.
It is another primary object of the present invention to introduce an electronic
scale assembly that can be directly incorporated into an apparatus, such as, for
example, a patient lifting device without adding height to the device or reducing
the overall height capability of the device.
It is yet another primary object of the present invention to provide an apparatus,
such as a patient lifting or transfer device, having an incorporated electronic
scale assembly which is more reliable and efficient than otherwise merely adding
"off the shelf" scale accessories onto a similar patient lifting or transfer device
or other apparatus such as those that simply measure applied weights without a
lifting or transfer mechanism but are capable of receiving or transmitting eccentric
or off-center loads.
Therefore and according to a preferred aspect of the present invention,
there is provided a scale assembly including:
- an axial force transducer having a primary load axis extending through
the center of said transducer, said axial force transducer being pivotally attached
to a support member; and
- a load supporting member including means on opposing sides thereof for
supporting a load wherein said load supporting member is pivotally attached to
said axial force transducer along at least one pivot axis that is orthogonal to
the primary load axis and extends substantially through the center of said axial
force transducer wherein; components of said supported load other than axial loads
transmitted along said primary load axis are not transmitted to said axial force transducer.
Preferably, the load supporting member can freely pivot about at least
one axis that is located in a plane that is substantially orthogonal to the primary
load axis of the axial force transducer while the transducer remains supported
in an axial orientation so as not to import any induced side loads or torque skewing
to the transducer.
In addition, the load supporting member is preferably maintained at the same
height
relative to the axial force transducer of the scale assembly. In a preferred embodiment,
the load supporting member is maintained in a plane at the center of an axial force
transducer cell. Therefore, the scale assembly does not substantially reduce the
lifting range of an apparatus, such as a patient/lift transfer device.
In a preferred version, the axial force transducer is disposed within an inner
supporting member and the load supporting member, supporting a load, is defined
by the load supporting member housing each of the inner supporting member and axial
force transducer.
The load supporting member is and inner supporting member pivotally attached
to the axial force transducer through at least one axis extending substantially
through the center of said axial force transducer and in a plane that is orthogonal
to the primary load axis; and supporting a load on said load supporting member
in this configuration.
More preferably, the scale assembly includes electronics including a display
in which the load output can be read by the user. The apparatus can further include
means for detecting when the load supporting member has pivoted beyond a predetermined
angular position relative to the apparatus.
According to yet another preferred aspect of the present invention, there
is provided a patient lift/transfer apparatus comprising:
- a lift mechanism for lifting a patient;
- a load supporting member attached to said lift mechanism; and
- an electronic scale assembly including an axial force transducer having
a primary load axis extending through the center of said transducer, said axial
force transducer being pivotally attached to said lift mechanism and means for
pivotally attaching said load supporting member to said axial force transducer
about at least one pivot axis permitting said load supporting member to freely
pivot about said at least one pivot axis, while said axial force transducer is
maintained in said axial orientation, said at least one pivot axis being orthogonal
to said primary load axis and extending substantially through the center of said
axial force transducer.
According to yet another preferred aspect of the present invention, there
is provided a method for isolating non-axial forces from an axial force transducer
in an apparatus, said axial force transducer having a primary load axis extending
through the center of said transducer, said method including the steps of:
- mounting said axial force transducer to said apparatus;
- attaching a load supporting member to said axial force transducer, said
load supporting member being pivotally attached to said transducer through at least
one pivot axis extending substantially through the center of said transducer and
in a plane orthogonal to the primary load axis; and supporting a load on said load
supporting member wherein non-axial loads are not transmitted to said axial force transducer.
An immediate and substantial advantage of the scale assembly of the present invention
is that an electronic scale can be incorporated or integrated into any suitable
apparatus without introducing substantial loss of height thereto.
A further advantage of the present invention is that the mounting of the load
supporting
member relative to the load cell or other axial force transducer of the scale assembly
minimizes the inducement of side loads being transmitted to the transducer and
therefore produces improved accuracy and greater reliability than previously known
"accessory" type devices.
These and other objects, features and advantages will become apparent from
the following Detailed Description which should be read in conjunction with the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partial isometric view of the lifting mechanism of a patient lifting
device illustrating the incorporated electronic scale assembly according to a preferred
embodiment of the present invention;
FIG. 2 is a front isometric view of the patient lifting device of FIG. 1;
FIG. 3 is an exploded front isometric view of the electronic scale assembly
of FIGS. 1 and 2;
FIG. 4 is a partial front view of the electronic scale assembly of FIGS. 1-3
illustrating the pivot ability of the spreader arm portion relative to a vertically
oriented load cell; and
FIG. 5 depicts a partial front isometric view of an electronic scale assembly
in accordance with another preferred embodiment of the present invention.
DETAILED DESCRIPTION
The following description refers to a specific embodiment of an electronic scale
assembly that is incorporated into an apparatus. In the following embodiments,
a specific patient lifting or transfer device is utilized. It will be readily apparent
from the following discussion, however, that there are a varied number of designs
of other suitable weight measurement systems that may or may not include lifting
mechanisms and other forms of patient transfer devices, such as, for example, ceiling
mounted versions, that can be effectively utilized incorporating the inventive
aspects and features of the present electronic scale assembly. In addition, certain
terms are used throughout the course of discussion, such as "top", "bottom", "lateral",
"horizontal", "transverse", "orthogonal", "axial" and the like that are used merely
to provide a frame of reference with regard to the accompanying figures. These
terms, however, are not intended to be overly limiting of the claimed invention.
Referring to FIG. 1, there is shown a patient lifting or transfer device
10. This lifting device
10 comprises a bottom base assembly
14
that includes a pair of long parallel base sections
18 and a pair of short
parallel base sections
21, each pair of sections extending horizontally
from a transverse support beam
20 wherein the long parallel base sections
form a substantially U-shaped support configuration. A support post
22 extends
vertically from the center of the span of the transverse support beam
20,
an upper portion of which is angled outwardly with respect to the long parallel
sections
18 of the base assembly
14 and including a yoke
29
at its upper end.
A lift mechanism
26 pivots on the support post
22 and extends to
an articulating boom arm
30 that is caused to move along a predetermined
travel path by means of a hydraulic lift cylinder
35 having one end that
pivotally engages an intermediate portion of the boom arm, the boom arm being pivotally
supported at the yoke
29 located at the top of the support post
22
at a proximal end
37, the mechanism being operable by a controller
38.
A handle assembly
28 is further attached by conventional means to the angled
portion of the support post
22 at a convenient height to permit the patient
lifting device
10 to be movable, each of the parallel sections
18,
21 of the base assembly
14 including casters
19 at their respective
ends opposite the transverse support beam
20 to permit movement of the device
along a substrate (not shown).
The articulating boom arm
30 of the lift mechanism
26 extends upwardly
and inwardly relative to the parallel base sections
18 of the base assembly
14 and includes a distal end
31. The distal end
31 of the
arm
30 extends outwardly to a distance which is not outside that of the
ends of the long parallel sections
18 in order to maintain overall stability
of the device
10. The distal end
31 also includes an engagement member
such as a hook or clevis
34, that is used for pivotally supporting an electronic
scale/load supporting member assembly
40, described in greater detail below,
which in turn is used to support a patient, such as by means of a body sling
50
or other patient support, the sling being attached by sets of straps
52
disposed on lateral sides thereof to the assembly
40 through corresponding
eyelets
60 that are provided on extending attachment portions
64
that are provided on opposing sides of a load supporting member, in this instance,
a spreader bar
82, also as described in greater detail below.
It should be reemphasized that there are a number of varying patient supports
as well as an accompanying varied number of spreader bar and load supporting member
designs that are complementary to those supports depending, for example, on whether
the patient alone is to be lifted from a gurney, a bed, a pool, a vehicle or other
station or a patient including a wheelchair, for example, is to be lifted, and
other factors. The preceding, therefore, is only intended to be an example of a
suitable patient support for use with the herein described invention.
Turning to FIGS. 2 and 3, additional details regarding the electronic scale/load
supporting member assembly
40 in accordance with this embodiment are herein
provided. This assembly
40 is defined by two major subassemblies, namely
a spreader bar subassembly and a scale subassembly that are integrated together
within a casing
54, shown only in FIG. 2. The scale subassembly includes
a tensile load cell
58, such as a SR Instruments Model—SM 7394 or
other similarly known axial force transducer that is disposed within a first or
inner supporting member
66. The casing
54 further includes a bottom
plate
98, also only shown in FIG. 3, which defines an enclosure for the
entire assembly
40. The scale subassembly further includes sensing and display
means such as a printed circuit board
108 containing a microprocessor as
well as a display
112 that are each disposed within a space between a wall
100 and a battery compartment
102 to one side of the top of the bottom
plate
98 of the casing
54 and are operatively coupled to the output
of the tensile load cell
58, the display being located relative to a slot
56 in the casing
54 where it can seen by a user following assembly thereof.
The bottom plate
98 further includes the battery compartment
102
for retaining a nine-volt alkaline or other suitable battery
104 for powering
the components of the scale subassembly and including a removable cover
103.
It should be pointed out that details relating to load cells and other axial force
transducers and to their electrical interconnection to an output display through
relevant circuitry are commonly known in the field and do not form a novel part
of this invention. The mechanical interconnection of the tensile load cell
58
to the assembly
40 and to the load supporting member, however, shall now
be described in greater detail for purposes of this embodiment. As such, FIGS.
1,
2 and
4 do not illustrate the casing
54 or bottom plate
98 in order to more clearly depict and amplify discussion relating to these features.
Still referring to FIGS. 2 and 3, the scale subassembly further includes the
first or inner supporting member
66 that includes a tubularly shaped cavity
62 into which the load cell
58 is disposed. This member
66
is defined by a pair of open ends, a pair of opposing lateral sides and a bottom
and top surface, respectively.
A support member
44 extends through an opening
86 that is provided
in the top surface of the casing
54, the support member being capable of
engaging the engagement member
34 extending from the distal end
31,
FIG. 1, of the articulating boom arm
30, FIG. 1. The support member
44
extends downwardly through openings
90 and
94 into the top surface
of the tensile load cell
58 respectively, thereby retaining the load cell
58 in a substantially stationary, but pivotable position relative to the
boom arm
30. Moreover, the load cell
58 according to this configuration
is mounted such that the load cell's primary load axis
84 (e.g., the axis
defining where tensile loads are applied) is substantially vertical, as dictated
by the position of the distal end
31, FIG. 1, of the boom arm
30,
FIG. 1.
A spacer plate
80 is mounted to the exterior of the bottom surface of
the
inner supporting member
66 for positioning the load cell
58 within
the inner supporting member. The spacer plate
80 is mounted in overlaying
relation onto the exterior of the bottom surface of the inner supporting member
66 and includes openings for securing the plate to the bottom of the load
cell
58 using a set screw
68 or other suitable fastener(s). An adjacent
set screw
69 is used for lateral alignment thereof.
A first pair of aligned openings
70 are respectively provided on the opposing
lateral sides of the inner supporting member
66. A first pair of bearings
74 are disposed in each of these openings
70. In addition, the tensile
load cell
58 includes an axial opening
59 extending through the body
of the load cell which when properly positioned within the cavity
62 of
the inner supporting member
66, is aligned with the openings
70.
The purposes of each of these openings
59,
70 will be described in
greater detail below.
Still referring to FIGS. 2 and 3, the load supporting member
82, includes
a housing defined by an open-top cavity
88 that is sized for receiving each
of the inner supporting member
66 and contained tensile load cell
58.
A second pair of aligned openings
76 are provided on respective opposing
lateral sides, these openings being further aligned with the first pair of aligned
openings when the first supporting member
66 is placed within the cavity
88 and in which bushings or bearings
78 are mounted within each opening.
The load supporting member
82 includes a set of extending attachment portions
64 on opposing end sides thereof, each of the extending attachment portions
including eyelets
60 sized for receiving the straps
52, FIG. 1, of
the body sling
50, FIG. 1. It should be noted that the load supporting member
can include multiple configurations, including those in which the extending attachment
portions are angularly "swept down" from a primary section of the subassembly that
is aligned like the supporting member
82 relative to the tensile load cell
58.
The load supporting member
82 is mounted so as to be pivotally mounted
relative to the scale subassembly and more particularly to the load cell
58.
According to this embodiment, the openings
70 in the inner supporting member
66 and the load supporting member
82 retaining the tensile load cell
58 extend along a pivot axis
96 which is substantially perpendicular
(e.g. horizontal) to the force axis
84 of the load cell
58. A shoulder
screw
77 or other suitable form of fastener is positioned through each of
the openings
76,
70 and
59 of the load supporting member,
inner supporting member
66 and the tensile load cell
58, respectively,
the screw being retained in place by a washer
79 and nut
81 combination
though it should be readily apparent that other suitable fasteners and retaining
means can be utilized. A pair of additional openings
72 are provided on
each lateral side of the load supporting member
82 that are aligned together.
A pair of axial rods
75 are routed through the openings
72, wherein
the rods limit the inner supporting member
66 and load cell
58 from
pivoting along axis
96, wherein the inner supporting member includes a spaced
portion to permit the passage of the rods
75 as bordered by upper edges
92. A pair of limit switches
116 are operatively coupled to the display
electronics to indicate when the upper edges
92 of the inner supporting
member
66 contacts the axial rods
75 at a predetermined angular position.
In this position as shown most clearly in FIG. 4, and according to this embodiment,
the center of the load cell
58 is co-planar with the the load supporting
member
82, as shown more clearly in FIG. 4, and therefore there is no increase
in height required to incorporate the load cell
58 into the lifting mechanism
26. As previously noted, the line of force axis
84 of the tensile
load cell
58 is substantially vertical depending on the position of the
distal end
31 of the articulating boom arm
30, based on the pivotal
attachment between the scale subassembly and the engagement member
34 with
the load supporting member
82 being freely pivotal about the pivot axis
96 extending through the center of the tensile load cell
58 and being
further movable along with the remainder of the electronic scale assembly
40
in at least two other degrees of freedom, that is, being rotatable 360 degrees
about the horizontal plane (that is the plane which is orthogonal to the force
axis
84), as well pivoting about the axis
107 (in this configuration,
in a direction which is orthogonal to the force axis
84 and the pivot axis
96) of the boom arm
30.
In use and referring to the Figs, the lifting mechanism
26 is used in a
conventional manner using the articulating boom arm
30 and hydraulic lift
mechanism
26 to transfer a patient (not shown) that is placed in the body
sling
50. Upon the addition of weight, the tensile load cell
58 is
acted upon and detects the vertical tensile force acting thereupon. It should be
noted that though the
82 according to this embodiment spans only approximately
5-8 inches between the eyelets
60 of the extending attachment portions
64,
this distance can easily be varied. For example and according to a preferred embodiment,
a load supporting member includes a total span of about 30-38 inches.
If the weight is unbalanced; that is, if the patient is not centered on the body
sling
50, FIG. 1, the effect of which is shown in FIG. 4, an eccentric load
is developed. However, because of the pivotal mounting of the load supporting member
82 through the center of the tensile load cell
58, only the axial
(e.g. vertical) components of these applied loads are transmitted for display by
the electronics of the scale.
It should be noted that in the present embodiment, the boom arm
30 of
the
lifting apparatus can also pivot, according to axis
107, depicted pictorially
in FIG. 2, in a fore and aft movement. During this pivoting, the load cell
58
is no longer vertical as defined herein and hence creating the potential measurement
error caused by the creation of a non-axial force component. This can occur, for
example, if the patient were not to remain centered in the body sling
50,
particularly if the patient were to assume an extreme fore or aft position. Similar
off-center loading can be visualized for other forms or applications of apparatuses
for which the above scale assembly, when incorporated therewith, can be proved
as useful.
Referring to FIG. 3, one possible method for preventing or at least minimizing
the contributions of excessive fore and aft movements of the scale assembly, FIG.
1, from overly contributing to the tensile load cell
58 would be to install
a sensor
120 for determining when the scale assembly has reached an angle
that is deemed sufficient to affect the required accuracy of the scale. Sensor
120 according to the present embodiment is a bubble-type level sensor mounted
to the exterior of the scale assembly, though it should be apparent that other
suitable forms of detection can easily be substituted.
According to a another preferred embodiment or technique and referring
to the orientations shown in FIG. 2, and other than supplying a means for detecting
whether excessive fore and aft movement has been effected, the load supporting
member could be redesigned to permit pivoting about the axis
107 by redesigning
each of the inner and outer supporting members so as to create a pivot axis that
is parallel with axis
107. For example, one possible design would essentially
be an assembly almost identical to the scale assembly
40, but with the lateral
and end sides thereof essentially reversed.
According to another alternate embodiment in accordance with the present
invention, an electronic scale assembly is designed to permit pivoting anywhere
along the horizontal plane of the boom pivot.
An example is depicted in FIG. 5. The electronic scale assembly
124 of
this embodiment is similar to that previously described and includes an inner supporting
member
126 that is held within an appropriately sized cavity of load supporting
member
130. An axial force transducer, such as tensile load cell
134,
is retained within a retaining cavity of the inner supporting member
126.
A housing or casing is also included that covers the entirety of the assembly
124,
but is not shown for the sake of clarity. A pivoting mounting bracket
138
is attached to the tensile load cell
134 by means of a mounting stud
154
fixedly attached at the center of the span of the bracket, the stud
154
being fixedly attached to the top of the tensile load cell provided through an
opening
158 in the upper supporting member
126.
The pivoting mounting bracket
138 is essentially U-shaped and includes
a pair of downwardly depending sections
142 at either end thereof, each
depending section including attachment points
144 to permit attachment to
a supporting structure, such as a patient lifting boom (not shown) or other structure.
The tensile load cell
134 is pivotally attached to the inner supporting
member
126 in a manner similar to that previously described in FIG. 2 by
means of a shoulder screw or suitable fastener(s) passing through the center of
the load cell
134 through a wall of the load supporting member
130
through a pivot axis
160 and secured by means of a nut
140. The tensile
load cell
134, like the preceding, is defined by a primary load axis
164
extending substantially vertically, also as previously described.
The load supporting member
130 is pivotally supported by the shoulder
screw
136 and like the preceding embodiment of FIGS. 2-4 includes a spreader
bar for supporting a load (not shown), defined essentially by the load supporting
member
130 that includes a pair of opposing extending attachment portions
146, each attachment portion having an eyelet
150, the extending
attachment portions being provided on opposite lateral walls of the load supporting
member
130 that are 90° to the pivot axis
160.
The load supporting member
130 of this embodiment is somewhat larger in
height than the preceding version of FIGS. 2-4. In this assembly, the attachment
points
144 of the downwardly extending portions
142 of the pivoting
mounting bracket
138 are aligned with the center of the tensile load cell
134 through axis
168 wherein pivot axes
168 and
160
are coplanar at the center of the tensile load cell.
PARTS LIST FOR FIGS.
1-
5
10 patient lifting device
14 bottom base assembly
18 long base sections
19 casters
20 transverse support beam
21 short base sections
22 support post
26 lift mechanism
28 handle assembly
29 yoke
30 articulating boom arm
31 distal end
34 engagement member
35 hydraulic lift cylinder
37 proximal end
38 controller
40 electronic scale assembly
43 arrows
44 support member
48 top surface
54 casing
56 slot
58 tensile load cell
59 axial opening
60 eyelets
62 cavity
64 extending attachment portions
66 first or inner supporting member
68 set screw
69 set screw
70 openings
72 openings
74 bearings
75 axial rods
76 openings
77 shoulder screw
78 bearings
79 washer
80 spacer
81 nut
82 load supporting member
84 force axis
86 top opening
88 cavity
90 opening
92 upper edges
94 opening
96 pivot axis
98 bottom plate
100 wall
102 battery compartment
103 cover
104 battery
107 pivot axis
108 printed circuit board
112 display
116 limit switches
120 sensor
124 electronic scale assembly
126 inner supporting member
130 load supporting member
134 tensile load cell
136 shoulder screw
138 pivoting mounting bracket
140 nut
142 downwardly depending portions
144 attachment points
146 extending attachment portions
150 eyelets
154 mounting stud
158 opening
160 axis, pivot
164 primary load axis
168 axis, pivot
While the present invention has been particularly shown and described with
reference to the preferred mode as illustrated in the drawings, it will be understood
by one killed in the art that various changes in detail may be effected therein
without departing from the spirit and scope of the invention as defined by the claims.
*
