Note: Descriptions are shown in the official language in which they were submitted.
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MEDICATION CART WITH HEIGHT ADJUSTMENT
FIELD OF THE I VENTION
The present invention relates to a medication cart of the type
comprising a housing defining a generally horizontal counter top providing a
work
s surface for receiving work materials involved in dispensing medications and
a
plurality of drawers underneath the counter top for containing medications and
for
containing data charts relating to medications to be dispensed to a number of
patients, where the housing is mounted on a base witlh ground wheels to be
moved
by an operator over the ground to different locations to service a series of
patients
with the medications.
BACKGROUND OF THE INVENTION
Medication carts of this type have become widely used in irrstitutional
settings for transporting and supplying medications to the patients. Carts of
this type
generally include a series of drawers and other compartments which are
provided to
contain the medications for the different patients together with the charts or
other
data which are used for the patient to record and Identify the medications
involved.
One form of cart manufactured by Manrex who are the assignee of the
present application includes a housing defined by frame members including four
posts which sit on a base Including ground wheels by which the operator can
move
the cart from place to plaCe. Carts of this type are relatively inexpensive
and have
obtained widespread acceptance.
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Other designs of cart are manufactured by other companies for
basically the same purpose and include the same general components including a
work top surface on which the materiais are placed prior to or during
dispensing.
One problem that has arisen is that of locating the worktop surface at a
suitabie
height for different height operators. For many years operators of different
heights
have accepted that it is necessary for them to accommodate equipment which is
insufficiently adjustable or inadequately adjusted. However in recent years it
has
become much more acquired that equipment of this type be adjustable to
accommodate the differing height of the operators who may be involved in using
the
jo equipment. This is particularly necessary in an institutional situation
where
management and employees are very sensitive to situations which may cause or
exacerbate medical difficulties amongst the operators.
Previous designs have therefore been provided of a cart of this type in
which a height adjustment can be provided for adjusting the distanoe of the
worktop
surface from the floor. One example is shown in PCT published application
2004/076604 published September 10, 2004 by Rubbermaid Commercial Products
LLC. This arrangement includes an upper housing having a series of
compartments
which is mounted on a single post where the post is carrieed at its lower end
on a
wheeled base. The post includes a sleeve type arrangement by which the height
of
the post can be adjusted.
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SUMWIARY OF THE INVENTION
It is an object of the present invention to provide an improved
medication cart which is more ergonomically suitable for different height
operators.
According to a first aspect of the invention there is provided a
medication cart comprising:
a frame having a piurality of upstanding posts at spaced comers of the
frame;
a generally horizontal counter top connected to the frame and
providing a work surface for reCeiving work materials involved in dispensing
jo mediqtions;
a plurality of drawers carried on the frame underneath the counter top
for sliding movement from a closed position within the frame to an open
position
aiiowing access to an interior of the drawers;
the drawers having locations therein for containing medications and for
containing data charts relating to medications to be dispensed to a number of
patients;
a base for supporting the frame and the drawers therein;
a plurality of ground wheels mounted on the base by which the base
and the frame carried thereon can be wheeled by an operator over the ground to
2o different locations to service a series of patients with the medications;
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each of the posts having a screw lifting jack mounted therein by which
the post and the frame can be lifted reiative to the base to raise the height
of the
counter top to accommodate different heights of the operator,
and a drive transmission for transferring drive to each of the screw
s lifting jacks for simultaneous actuation of the screw iifting jacks to raise
the frame
relative to the base.
Preferably each screw lifting jack includes a threaded rod extending
IongitudinaAy of the respective post within the respective post and a nut
mounted on
the threaded rod.
Preferably the drive transmission is arranged to drive rotation of the
threaded rods and wherein each nut is mounted on the frame such that rotation
of
the threaded rod causes movement of the nut along the threaded rod and lifting
of
the frame. However as an aitemative, the rods may be stationary and the nuts
commonly ddven by a common drhre system. The nuts are preferably coupled to
the
frame with the rods fixed to the base since the base is close to the ground
and
sufficient movement of the housing is obtained by holding the rod in fixed
axial
position on the base and by moving the nuts along the rods. However in
altemative
arrangements the rods may be moved axially and nuts held stationary. The term
"nut used herein is Intended to include any element which has a threaded
internal
female thread for engaging the rod and is not intended to be limited to any
particular
external shape of the nut. Thus the nut may be formed by a sleeve.
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Preferably the drive transmission includes a drive coupling mounted on
the base for communicating drive to each of the threaded rods.
Preferably one threaded rod includes an element thereof which
extends to a top of the respective post and carries a drive member at the top
such
5 that drive to all of the threaded rods is communicated from the drive
member. This
is particularly convenient for the operator in that the drive member is
readily
available at the top of the housing. However the drive may be communicated to
the
rods at any other suitable location.
Preferably the drive member comprises a hand crank. However a
to motor may be provided powered by any suitable source preferabiy a battery.
Preferably the drive coupling comprises an endless flexible drive
member which passes around a drive connection to each of the rods.
Preferably the endless flexible drive member comprises a chain which
engages a sprocket on the respective rod. However timing belts and other drive
connecting members of a similar nature which maintains common drive between
the
sprockets can be used.
According to a second aspect of the invention there is provided a
medication cart comprising:
a frame having a plurality of upstanding posts at spaced corners of the
2o frame;
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a generally horizontal counter top connected to the frame and
providing a work surface for receiving work materials involved in dispensing
medications;
a plurality of drawers carried on the frame underneath the counter top
s for sliding movement from a closed position within the frame to an open
position
allowing access to an interior of the drawers;
the drawers having locations therein for containing medications and for
containing date charts relating to medications to be dispensed to a number of
patients;
a base for supporting the frame and the drawers therein;
a piuraiity of ground wheels mounted on the base by which the base
and the frame carried thereon can be wheeled by an operator over the ground to
different looations to service a series of patients with the medications;
each of the posts having a threaded rod therein extending axially
therealong with a lower end of each rod attached to the base;
each threaded rod having mounted thereon a respective nut connected
to the frame such that rotation of the rods causes axial movement of the nut
along
the rod and lifting of the frame relative to the base;
and a drive transmission for transferring drive to each of the threaded
2e rods for simuftaneous rotation of the threaded rods to raise the frame
relative to the
base.
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According to a third aspect of the invention there is provided a
medication cart comprising:
a housing;
a generally horizontal counter top at the top of the housing and
providing a work surface for receiving work materials involved in dispensing
medications;
a plurality of drawers in the housing undemeath the counter top for
sliding movement from a closed position within the frame to an open posidon
allowing access to an interior of the drawers;
the drawers having locations therein for containing ntedications and for
containing data charts relating to medications to be dispensed to a number of
patients;
a base for supporting the housing and the drawers therein;
a plurality of ground wheels mounted on the base by which the base
is and the frame carried thereon can be wheeled by an operator over the ground
to
different locations to service a series of patients with the medications;
a lifting mechanism for lifting the housing relative to the base including
a plurality of threaded rods extending generally upwardly between the base and
the
housing with a lower end of each rod attached to the base;
each threaded rod having mounted thereon a respective nut such that
rotation of the rods causes axial movement of the nut along the rod and
lifting of the
housing relative to the base;
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and a drive transmission for transferring drive to each of the iifting
mechanisms for simultaneous action in iifflng the housing reiative to the base
inciuding an endless flexible drive member extending around each of the
lifting
mechanisms in tum and a drive coupling eonnected between the endless drive
s member and the iifting mechanisms.
BRIEF DESCRIPTION OF THE DRAWINGS
Various other objects, features and attendant advantages of the
present invention will become fully appreciated as the same becomes better
understood when considered in conjunction with the accompanying drawings, in
io which like reference characters designate the same or similar parts
throughout the
several views, and wherein:
Figure 1 is an isometric view of a cart according to the present
invention.
Figure 2 is an isometric view of the cart of Figure 1 showing the bottom
is and opposite end.
Figure 3 is a bottom plan view of the cart of Figure 1.
Figure 4 is an end elevational view of the cart of Figure 1.
Figure 5 is a front eievationai view of the cart of Figure 1.
Figure 6 is a vertical cross section through the cart of Figure 1, the
2o cross section being taken along the lines 6-6 of Figure 5,
Figure 7 is a cross sectional view along the lines 7-7 of Figure 6.
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Figure 8 is an enlarged view of one portion of the structure of Figure 6
showing one post and its associated lifting system.
DETAILED DESCRIPTIQN OF EMBODIMENTS OF THE INVENTION
A medication cart generally indicated at 10 comprises a housing 11
j carried on a base 12. The housing 11 has a top work surface 13, two side
walls 14
and 15, a front wall 16 and a rear wall opposife to the front wall.
The top work surface 13 is horizontal and generally plain although it
may include receptacles for various components such as computers, bar code
readers and the like which are known to a person skilled in the art and assist
the
io operator of a cart of this type with the dispensing of the medications.
The housing 11 Is formed from a rectangular bottom frame 17, a
rectangular top frame 18 and four connecting posts 19, 20, 21 and 22. The
frame
members are formed from square tubing which is suitably connected at the
corners
to provide a generally rigid structure. The frame work is then covered by
panels to
15 form the sides and top of the housing.
The housing contains a series of compartments which can be located
and arranged in accordance with requirements. In the embodiments shown there
are a series of separate drawers 23 which are mounted on sliders carried in
the
housing so that each drawer can be moved from a stored position within the
housing
20 to an open position allowing access to the interior of the drawer. Each
drawer
includes a series of support elements 24 shown schematicaliy in Figure 6 which
allow the drawers to receive and contain cards of medications and data or
other
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information relating to the patients. Various types of storage systems can be
used.
The medications are generally but not necessarily contained on blister packs
so that
each patient has their requirement suitably stored in an arrangement which can
be
readily dispensed by the operator.
s Details of one example of arrangement of this type can be found by
studying the products available by the assignee to this present application.
Information relating to these products is well known to a person skilled in
the art.
The base 12 as best shown In the bottom view of Figure 3 is defined
by an exterior tubular frame 25 including a front frame member 26, two side
frame
io members 27 and 28 and a rear frame member 27. These are partly covered by
plates 28 leaving an open center section 29 so as to reduce the weight of the
structure. At each comer is mounted a wheel mount 30. Two of the wheel mounts
include fixed wheels 31 and 32 and two of the wheel mounts include castor
wheels
33 and 34 so that the base which carries the housing can be wheeled from place
to
is place easily by the operator. The number of wheels can of course be reduced
by
providing a single wheel at the front or rear.
There is provided a lifting system 40 for raising and lowering the
housing relative to the base 12. The lifting system 40 comprises 4 threaded
rods 41,
42, 43 and 44. Each threaded rod is attached to the base at a respective comer
and
2o is carried on bearings 45 so that the threaded rod is free to rotate around
its axis but
is supported against axial movement or side to side movement on the base by
the
fixed mounting of the bearing 45 on the base.
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Each of the threaded rods carries a sprocket 46 at its iower end
immediately adjacent the bearing 45 and located within the height of the base.
The
sprockets of the four threaded rods are arranged in a common plane within the
base.
A chain 47 is engaged around all of the sprockets so that the chain 47 passes
around the base from each sprocket to the next closely adjacent the peripheral
edge
of the base.
Each of the threaded rods extends into a respective one of the posts
19, 20, 21 and 22 so that the threaded rod is located freely inside the
respective
post. The post carries a nut 57 in the form of a sleeve which is fastened
inside the
to post and is held against axial or rotational movement relative to the post.
This is
conveniently formed by casting into the interior of the post a plastics member
which
defines a female thread on its inside surface and has an outside surface
engaging
the interior of the post. Thus the threaded rod engages into the female thread
on the
member within the post. In this way rotation of the threaded rod causes the
nut to
is move axially along the threaded rod.
As the threaded rods are interconnected by the sprockets 46 and the
chain 47, rotation of one of the threaded rods is communicated to common
rotation
of each of the threaded rods thus driving the screw jack arrangement formed by
the
threaded rods and its co-operating nut to commonly and simultaneously lift the
2o housing relative to the base.
One of the threaded rods or the chain can be driven by a motor
attached to the base or the housing. Thus for example an additional sprocket
may
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be provided on the chain which connects to a motor which drives the chain
around
the periphery thus driving each sprocket and thus causing common rotaaon of
the
threaded rods. The motor can be driven by battery power using a switch
provided at
a suitabie location and movabie by the operator to cause the lifting movement.
s In the alternative, as shown, one of the rods 42 includes an extension
portion 42A which extends through the respective post 21 to an upper end which
projects through the upper end of the post and through the upper surface 13 so
as to
be exposed at the upper end of the housing. A hand crank 42B can be
permanently
attached to the threaded rod or can be provided as a separate element for
io attachment to the upper portion 42A of the threaded rod, In this way
actuation of the
hand crank by the operator will very simply cause the rotation of the rod 42
and
therefore the rods of each of the posts.
In this way the operator can readily adjust the height of the work
surface to a required height suitable for the operator.
15 The device provides a simple construction which can be inexpensively
manufactured and is robust requiring iittle or no maintenance. The weight of
the
housing is relatively low so that the amount of manual effort necessary to
effect the
movement of the housing using a simple hand crank is small. The chain and
sprockets can be located simply within the base so as to avoid any increase in
size
20 or complexity of the structure. The threaded rods are conveniently housed
within the
posts with only the relatively small portion of the threaded rod between the
base and
the bottom of the housing being exposed.
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As will be apparent to those skilled in the art in the light of the
foregoing disclosure, many alterations and modifications are possible in the
practlce
of this invention without departing from the spirit or scope thereof.
