U.S. patent application number 12/131221 was filed with the patent office on 2008-09-25 for apparatus and method for assembling shelving units.
This patent application is currently assigned to ISO GROEP MACHINEBOUW B.V.. Invention is credited to D. J. KONING, Dirk Marinus POORTVLIET, W. STRUIJK.
Application Number | 20080230502 12/131221 |
Document ID | / |
Family ID | 36781511 |
Filed Date | 2008-09-25 |
United States Patent
Application |
20080230502 |
Kind Code |
A1 |
POORTVLIET; Dirk Marinus ;
et al. |
September 25, 2008 |
APPARATUS AND METHOD FOR ASSEMBLING SHELVING UNITS
Abstract
An apparatus is described for assembling a shelving unit
consisting of a frame and a plurality of detachable shelves
supported by the frame. The apparatus comprises a supply section
for supplying a shelf, a testing section for inspecting the
supplied shelf, a positioning section for gripping an approved
shelf and subsequently mounting the shelf in the frame, and a
control unit for controlling the apparatus. It is used in
particular for carts for the transport of plants.
Inventors: |
POORTVLIET; Dirk Marinus;
(ZUILICHEM, NL) ; KONING; D. J.; (SON EN BREUGEL,
NL) ; STRUIJK; W.; (DELWIJNEN, NL) |
Correspondence
Address: |
HOWREY LLP-EU
C/O IP DOCKETING DEPARTMENT, 2941 FAIRVIEW PARK DR., SUITE 200
FALLS CHURCH
VA
22042
US
|
Assignee: |
ISO GROEP MACHINEBOUW B.V.
GAMEREN
NL
|
Family ID: |
36781511 |
Appl. No.: |
12/131221 |
Filed: |
June 2, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
PCT/EP2006/069154 |
Nov 30, 2006 |
|
|
|
12131221 |
|
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Current U.S.
Class: |
211/187 ;
211/186 |
Current CPC
Class: |
Y02A 40/25 20180101;
A01G 9/143 20130101; Y02A 40/252 20180101; B23P 19/04 20130101 |
Class at
Publication: |
211/187 ;
211/186 |
International
Class: |
A47B 57/26 20060101
A47B057/26 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 2, 2005 |
NL |
1030586 |
Claims
1. Apparatus for assembling a shelving unit comprising a frame and
a plurality of detachable shelves supported by the frame, the
apparatus comprising: a supply section for supplying a shelf; a
testing section for approving or rejecting the supplied shelf;
correcting elements arranged to grip the shelf with a force
sufficient to distort partially distorted shelves into a desired
pattern for approval by the testing section; a positioning section
for gripping an approved shelf and subsequently mounting the shelf
in the frame; and a control unit for controlling the apparatus.
2. Apparatus according to claim 1, wherein the correcting elements
are arranged to grip the shelf with a force of at least 1000 N.
3. Apparatus according to claim 1, wherein the shelf is provided
with support elements which fit on supports in the frame and
wherein the correcting elements are arranged to grip the support
elements.
4. Apparatus according to claim 1, wherein the testing section
further comprises a measuring element.
5. Apparatus according to claim 4, wherein the testing section is
able to determine a number of dimensions of the shelf, selected
from the group consisting of: width; length; depth; degree of
concavity; curvature; torsion; the presence of an edge; and the
position and presence of support elements.
6. Apparatus according to claim 5, wherein the control unit stores
a number of standard dimensions of a shelf and the testing section
compares the dimensions with the standard dimensions and rejects a
supplied shelf that deviates from the standard data.
7. Apparatus according to claim 1, wherein the testing section
comprises a number of sensors and the sensors are mechanically
adjustable.
8. Apparatus according to claim 1, further comprising a disposal
section for removal of the rejected shelves.
9. Apparatus according to claim 1, wherein the shelf is provided
with support elements which rest on supports in the frame and
wherein the positioning section comprises gripping elements which
grip the support elements.
10. Apparatus according to claim 1, wherein the frame consists of
separate components that are each provided with supports, the
apparatus further comprising a leveling system to level the heights
of the supports of the separate components of the frame.
21. Apparatus for assembling a shelving unit comprising a frame and
a plurality of detachable shelves to be supported by the frame, the
apparatus comprising: a supply section for supplying a shelf; a
testing section for approving or rejecting the supplied shelf; a
positioning section for gripping an approved shelf and subsequently
mounting the shelf in the frame; a lifting element for adjusting
the height of the frame or the testing section such that a gripped
shelf may be mounted at a height in the frame which is
substantially in accordance with the height of the testing section;
and a control unit for controlling the apparatus.
12. Apparatus according to claim 11, wherein the positioning
section comprises the lifting element, which is arranged for
lifting the frame such that a gripped shelf may be mounted at a
height in the frame which is substantially in accordance with the
height of the testing section.
13. Apparatus according to claim 11, wherein the supply section
supplies the shelves one by one from a stack at substantially the
same height as the testing section.
14. Apparatus according to claim 13, wherein the supply section
comprises two belts mounted over rollers, between which belts the
stack of shelves can be gripped, which belts may be actuated to
rotate such that the gripped shelves may be supplied in a
controlled manner.
15. Apparatus according to claim 11, wherein the supply section
comprises suction cups for placing a shelf in the testing
section.
16. In an apparatus for assembling a shelving unit comprising a
frame and a plurality of detachable shelves, an automated method
for assembling the shelving unit, comprising: supplying a shelf to
a testing section; testing a number of features of the shelf and
comparing the features with predetermined requirements; approving
shelves that meet the requirements gripping the approved shelf; and
mounting the gripped shelf in the frame.
17. Method according to claim 16, further comprising distorting the
shelf to adjust it to the predetermined requirements.
18. Method according to claim 17, wherein the distortion of the
shelf occurs by gripping a part of the shelf with a correcting
element with a force of more than 1000 N.
19. Method according to claim 17, further comprising rejecting and
removing shelves that do not meet the predetermined
requirements.
20. Method according to claim 16, in which the checking, approving,
gripping and mounting of a shelf occurs substantially at a constant
height.
21. Method according to claim 16, further comprising locating the
shelf to determine its position prior to mounting the shelf in the
frame.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of international
application no. PCT/EP2006/069154 filed on Nov. 30, 2006, which was
published under PCT Article 21(2) in English, the contents of which
are hereby incorporated by reference in their entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The current invention relates to an apparatus and a method
for assembling or putting together shelving units, in particular
trolleys for transporting flowers, plants and the like. The
invention further relates to systems comprising in combination a
plurality of such shelving units and an apparatus for assembling
the shelving units.
[0004] 2. Description of the Related Art
[0005] Shelving units are known in various fields. Particularly in
commercial fields, such shelving units may be assembled for use and
subsequently require dismantling for the purpose of transport or
storage. At certain locations, such as at the wholesaler's, this
process may take place frequently and may involve considerable
manpower.
[0006] It is known in the horticultural industry to use trolleys,
sometimes referred to as "Danish carts" to transport flowers and
other plants. These trolleys are in the form of mobile shelving
units comprising a rectangular base of approximately 1 m by 50 cm,
provided with wheels. Upright frame elements are inserted into
sockets at the four corners of the base and a number of shelves or
planks are supported by the frame elements. The shelves are
provided with hooks or pins for engagement with appropriate slots
in the frame elements. The number of shelves and their spacing will
vary according to the plants being transported. It is estimated
that 21 million of such trolleys are in operation worldwide and on
average each trolley will rotate back to a central depot four times
in a given year.
[0007] On returning empty to a depot, the trolleys are preferably
knocked-down or dismantled to save space. The shelves are removed
one by one from the frame elements by manipulating the hooks out of
the slots. Each shelf may then be stacked, e.g. on an empty
trolley. Broken or damaged shelves may be discarded or separated.
Finally, the uprights are disengaged from the base and the bases
and the uprights are stacked separately. This operation involves
considerable manpower. At the moment that the market gardener is
ready to harvest, a large number of trolleys needs to be put
together again to receive the harvest for transport.
[0008] Putting together such trolleys is a complex operation. In
particular, each trolley may be assembled differently with a
different number of shelves and a different spacing between the
shelves. Furthermore, different sorts of shelves have been produced
and these are now randomly distributed throughout the industry. As
a consequence, the shelves encountered in the assembly of a single
individual trolley may vary from one another, e.g. in their width
by up to 2 cm. Additionally, the shelves may be deformed or broken
and it may be difficult to insert them into the uprights of the
base.
[0009] There is thus a need to provide a system and an apparatus
wherein at least part of the inconveniences arising when assembling
such trolleys, may be overcome.
BRIEF SUMMARY OF THE INVENTION
[0010] According to the present invention there is provided an
apparatus for assembling a shelving unit consisting of a frame and
a plurality of detachable shelves supported by the frame, the
apparatus comprising: a supply section for supplying a shelf, a
testing section for approving or rejecting the supplied shelf; a
positioning section for gripping an approved shelf and subsequently
mounting the shelf in the frame; and a control unit for controlling
the apparatus. The control apparatus may control automatic or
semi-automatic operation of the supply section, the testing section
and/or the positioning section. By this combination of elements it
can be provided that only approved shelves, which meet certain
criteria, are mounted in the frame.
[0011] According to a preferred embodiment of the invention, the
testing section may comprise correcting elements which grip the
shelf with such a force to distort it to a desired pattern.
Supplied shelves may be deformed to such an extent that they would
no longer fit into the frame. In particular, they may be twisted or
bent. Also, the support elements which rest on the frame, may be
bent or even absent. Such deviations from a standard size may
hamper or obstruct assembling a shelving unit. By gripping certain
components of the shelf and by exerting a force, certain
irregularities may be repaired. To be able to distort and correct
the shelf, the correcting elements will preferably exert a force on
the gripped section of at least 1000 N. Preferably, this force may
even be over 2000 N. In general, the force exerted by the alignment
elements will be more than 10.times. the force that is necessary to
only grip and move the shelf. It is noted that the testing section
including the correcting elements may itself form the basis of an
invention and that the apparatus may be used without the
positioning section or with a simplified version thereof. The
device may then function to test a supply of shelves and correct
those shelves that deviate from the desired configuration: shelves
that after correction still fail to meet the desired configuration
being rejected. The accepted shelves may then e.g. be stored for
subsequent use.
[0012] According to a further feature of a preferred embodiment,
the shelf is provided with projecting pins that fit into slots in
the frame. These pins are gripped by the correcting elements such
that bent pins are straightened. It will be clear that shelves and
pins that do not deviate from the desired size or pattern, will not
or hardly be bent.
[0013] Preferably, the testing section is further provided with one
or more measuring elements, such that a number of dimensions of the
shelf may be determined in the testing section. Possible dimensions
may include: width, length, depth, degree of concaveness,
curvature, torsion, the presence of an edge, position and presence
of support pins and the like. The control unit is able to store a
number of standard dimensions of a shelf in a memory. Subsequently,
the testing section may compare the measured dimensions with the
standard dimensions and reject a supplied shelf that deviates as
such from the standard data. In a simple preferred alternative, the
standard dimensions may be established mechanically by the
positions of the sensors.
[0014] Shelves that do not meet predetermined requirements will be
rejected by the testing section. To this end, the apparatus further
comprises a removal facility capable of removing rejected shelves.
This may be e.g. an empty cart that is parked under the testing
section. On rejecting a shelf, the testing section may release the
shelf such that it is dumped into the cart.
[0015] A particularly important feature is the centering or other
such position determination of the shelf. In order for the shelf to
be quickly and correctly mounted in the frame, its precise position
and orientation with respect to a known reference point must be
known. For a shelf mounted on pins, the positions of the pins are
decisive. According to an important aspect of the invention, the
testing section is able to determine the location of the shelf
during the process of testing. To guarantee accurate handling of a
shelf, such that it fits into the frame, preferably, a standardised
or tested element of the shelf is then gripped in the positioning
section. With shelves that are provided with projecting pins which
fit into slots in the frame, preferably, the projecting pins are
determined. The positioning section may then be provided with a
number of gripping elements that grip the projecting pins. It is
also possible that in the positioning section a shelf is gripped at
another location, provided that the relative position of the
gripped component relative to the pins or possible other support
elements is well determined. Alternatively, this relative position
may be determined by the positioning section or otherwise, prior to
or during the mounting of the shelf in the frame
[0016] In a preferred embodiment, the positioning section further
comprises a lifting element to align the relative heights of a
gripped shelf with its desired position in the frame. The lifting
element may have the form of e.g. a robot arm, which is movable in
all directions to position a shelf from the testing section into
the frame. In another alternative, the frame or even the testing
section may be mounted on a lifting element for an up- and
down-movement. Because of this, it can be provided that a shelf is
essentially moved only horizontally from the testing section to the
positioning section. This is an extremely important factor in
determining the speed of the apparatus.
[0017] It is also important to be able to level the heights of the
individual components of the frame, before a shelf is fitted into
the frame. To this end, the apparatus may comprise a levelling
system to level the positions of the supports of the separate
components of the frame. Certain frames may be provided with
extension pieces for increasing the height of the frame. Means to
correctly position and level these extension pieces may also be
provided.
[0018] According to the preferred embodiment, the supply section
supplies shelves, one by one, from a stack. The stack is located
e.g. on a cart. The supply section may be a similar apparatus to
that described in co-pending U.S. application Ser. No. 11/660,316,
the contents of which are incorporated herein in their entirety.
According to that device, belts mounted over rollers grip the stack
of shelves. The belts may be inflated to grip the shelves and may
also be actuated to rotate such that the gripped shelves may be
supplied to the upper side of the belts in a controlled manner. By
supplying the shelves on the same level as the testing section, the
speed of the apparatus may be maximized.
[0019] To put a supplied shelf in its position in the testing
section, the supply section may also comprise an arm provided with
suction cups. It may cooperate with the aforementioned supply belt
or it may take shelves one by one from a stack. Instead of suction
cups, depending on the construction of the shelves, other similar
holding elements may be used, e.g. magnets.
[0020] The control unit may control the apparatus fully
automatically. To this end, only e.g. the desired locations of the
shelves in the frame should be indicated in advance, as well as the
rejection parameters. It is also possible to work partly
automatically as a result of which a driver may indicate each
desired position of a shelf and also may generate a rejection
signal based on measurements disclosed to him.
[0021] The current invention also provides a method for assembling
a shelving unit, wherein the shelving unit comprises a frame and a
plurality of detachable shelves supported by the frame, the method
comprising: supplying a shelf to an testing section; measuring a
number of features of the shelf and comparing the measurements with
predetermined requirements; approving a shelf that meets the
requirements; gripping the approved shelf; and mounting the gripped
shelf in the frame. In this way, because each operation may be
carried out mechanically, such a shelving unit may be put together
accurately and correctly with little effort and manpower.
[0022] As indicated above, the method may also comprise other
steps, such as correcting deviating shelves and rejecting and
removing shelves that do not meet the predetermined requirements.
The step of mounting the approved shelves in a frame may also be
omitted or performed e.g. manually at a later stage.
[0023] According to a preferred embodiment of the method, the
measuring, approving, gripping, mounting and optionally also
supplying a shelf, occurs at a substantially constant height, as a
result of which movement of the shelf is reduced and an increased
process speed may be realized.
[0024] The invention relates also to a system comprising a
combination of a shelving unit or trolley, which comprises a frame
and a plurality of detachable shelves supported by the frame, and
an apparatus for assembling the shelving unit as described
above.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] An embodiment of the invention will now be described in more
detail and will only serve as an example, with reference to the
attached figures in which:
[0026] FIG. 1. shows in perspective a cart for flowers for use in
the invention, including a detail of the connection between the
shelf and the uprights;
[0027] FIG. 2. shows a schematic system overview of the components
of an apparatus according to the invention;
[0028] FIG. 3. shows the supply section of a preferred embodiment
of the invention;
[0029] FIG. 4. shows the testing section of the preferred
embodiment of FIG. 3;
[0030] FIG. 4a shows the testing section such as in FIG. 4 when
inspecting a shelf;
[0031] FIG. 5. shows the positioning section of the preferred
embodiment of FIG. 3; and
[0032] FIG. 6. shows a plan view of the positioning section of FIG.
5.
DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS
[0033] FIG. 1 shows a perspective view of a cart 1 of the type
intensively used in the flower industry. The cart 1 comprises a
frame 2 and a plurality of substantially planar shelves 4 mounted
on the frame (for reasons of clarity only one shelf is depicted).
In the current example the frame comprises a base 6 mounted on
wheels 7. Each corner of the base has been provided with a socket 8
for receiving an upright 10. Although the invention will further be
described in relation to such a cart for flowers, it will be
immediately apparent for the person skilled in the art that the
invention is also applicable to other forms of trolleys or shelving
units. In this respect, it is assumed that the term shelf is not
restricted to simple planar shelves or plates. The term shelf also
comprises: shelving units; planks; baskets; cross elements and
other supporting parts that may be utilized in a shelving
system.
[0034] As is shown in detail in FIG. 1, each upright 10 comprises
an essentially U-shaped groove 18 wherein the support surfaces 14
are directed inwardly. The support surfaces 14 are provided with
elongated vertical slots 12 and the shelves 4 are provided with
pins 16 that fit into the slots 12 to keep the shelves 4 at the
desired height between the uprights 10. As will be further
described below, the uprights 10 may be removed from the sockets 8
for stacking the cart 1 for transport or storage. The uprights 10
can also be inserted into the sockets 8 such that the support
surfaces 14 face outwardly. In this orientation the shelves 4 can
be stacked on the cart 1 such that the pins 16 slide in the open
U-shaped groove 18 of the uprights 10. Although not shown,
extension pieces may be provided to optionally extend the uprights
10.
[0035] FIG. 2 shows a schematic overview of the components of an
apparatus 20 according to the invention. The apparatus 20 consists
of a supply section 22, a testing section 24, a positioning section
26 and a control unit 28. Although in the following, reference will
be made to physically separate sections that perform each task
separately and interact with one another, it will be understood,
that the sections may be integrated into combined sections that
perform a number of separate tasks.
[0036] A full cart 1 on which a number of shelves 4 are stacked, is
located in the supply section 22. The testing section 24 consists
of a correcting section 34 and a measuring section 36. Furthermore,
a transport bin 38 is located underneath the testing section 24. A
robot arm 40 is located in the positioning section 26. Within reach
of the robot arm 40 a second cart 1' is positioned which, in this
case, is in an uncompleted state. The control unit 28 is
electronically connected with the supply section 22, the testing
section 24 and the positioning section 26.
[0037] FIG. 3 shows in further detail the supply-22 and testing
sections 24 of a preferred embodiment of the invention with a fully
stacked cart 1. As can be seen in the details, the uprights 10 are
inserted into the sockets 8 such that the pins 16 of the shelves 4
slide into the open U-shaped groove 18 of the uprights 10. For the
sake of clarity, not all shelves 4 in the cart 1 are depicted. A
cart 1 may carry e.g. up to sixty shelves.
[0038] The supply section 22 includes a robot arm 30 and a supply
system 42. The robot arm 30 is provided with suction cups 32 that
are able to hold and to move a shelf 4 from the supply system 42.
The supply system 42 comprises a number of gripping belts 46,
mounted to rotate around a pair of rollers 48, 48'. Each belt 46 is
operated by a drive (not shown) provided on the lower roller 48.
The belt 46 is made of a resilient material. Within the space
defined by the belt 46 and the rollers 48, 48' an inflatable tube
50 is located. The inflatable tube 50 is supported by a plate 52 on
the side opposite to the shelves 4. The inflatable tube 50 may be
inflated by means not shown, as a result of which the resilient
belt 46 inflates and presses outwardly against the shelves 4. The
distension of the belt 46 is sufficient to compensate for possible
differences in size of the shelves 4. By operating the belts 46 to
counter-rotate, the shelves 4 may be moved upwardly to the height
of the robot arm 30.
[0039] To move a fully-stacked cart 1 into the supply section, the
belts 46 can be opened or moved apart from each other. It is also
possible to lower the belts 46 over the cart by rolling them down
from above.
[0040] In FIG. 4, the testing section 24 is shown more closely from
which it can be seen that the correction section 34 consists of a
frame 35 and four alignment elements 54. The frame 35 has a slot 53
with four hinged elements 66 of such a size that a shelf 4 in the
slot 53 can be supported by the hinged elements 66. This can be
seen in FIG. 4a. The alignment elements 54 have the shape of a pair
of tongs 56 that are operated by the force of a pneumatic cylinder
58. In a first position of the tongs 56 (FIG. 4) an opening is
located to receive the pins 16 of a shelf 4. A shelf 4 can be put
in the slot 53 on the hinged elements 66 by the robot arm 30 of the
supply section. Subsequently, the pair of tongs 56 will close using
a force of approximately 2000 N. Possible deviations of the pins 16
are thereby corrected. A precision of .+-.2 mm for the pins is
desired to ensure that they will fit well into the slots 12 in the
uprights 10.
[0041] In FIG. 4, a number of measuring elements of the measuring
section 36 can also be seen. Each pair of tongs 56 is provided with
a pin sensor 60 to guarantee the presence of a pin 16 in the pair
of tongs 56. It may have the shape of a contact electrode, possibly
in a plastic sleeve, that detects the metal pin 16. Also centering
elements 61 are provided with sensors 62 that detect the presence
of the metal strip forming the edge of the shelf Curvature sensors
64 measure the deviation of the centre of the shelf from its
desired position, as a result of which shelves that are undesirably
curved may be rejected. Although not further described herein,
other sensors e.g. optical, video, contact, piezo, may be applied
to determine e.g. the size, weight, cleanliness and otherwise the
state of the shelves.
[0042] Under control of the control unit 28, the signals of the
different sensors are registered. A shelf 4 satisfying the
measurements is approved and subsequently supplied to the
positioning section 26. A shelf 4 that does not satisfy one or more
measurements is rejected. By folding away the hinged elements 66
and opening of the pair of tongs 56, the rejected shelf 4 drops
into the waiting transport bin 38. The transport bin 38 may also be
an empty cart and the shelf 4 may then be introduced in a
controlled manner between the uprights 10.
[0043] In the embodiment shown in FIG. 4, the sensors are
mechanically adjusted feelers. This means that the position of the
sensor itself determines the accuracy of the result. Therefore, by
adjusting the curvature sensors 64 to a higher position, the
tolerance for curvature of a shelf is reduced. In an alternative
variant, instead of sensors, actual measuring elements may be used
to measure all important dimensions and properties of the shelf 4
and to compare against predetermined standard dimensions. The
standard dimensions and the acceptable tolerances are stored in a
memory of the control unit as a pattern. The memory could then
store several patterns for use with several dimensions or features
of a cart. This could also possibly be indicated automatically e.g.
by a label or bar code on the shelves.
[0044] FIG. 5 shows in more detail the positioning section 26
according to the invention. The positioning section 26 comprises a
robot arm 40 and a lifting element 68. The robot arm 40 is provided
with a gripping part 70 that ensures gripping of the shelf 4. A
cart to assemble 1' is mounted on the lifting element 68. By using
the lifting element 68, it is possible to move the cart 1' upwards
and downwards such that slots 12 for the next shelf 4 to be mounted
are always at the same height. This height is then preferably
adjusted to the height of the frame 35 of the testing section 24.
To ensure that the slots 12 in all four uprights 10 are in the same
position, the lifting element 68 is provided with calibration
elements 74. The calibration elements 74 register the height of the
bottom slot 12 in each upright 10 and transmit it to the control
unit 28. By doing so, the uprights 10 may be independently adjusted
to the same height by not further specified adjusting facilities.
Of course, other ways of adjusting the uprights 10 may also be
envisaged.
[0045] In FIG. 6, a plan view of the positioning section 26 is
shown. It can be seen that the gripping part 70 comprises four
gripping elements 72 each gripping a pin 16 of the supplied shelf
4. Because the shelf 4 has been inspected closely, the positions of
these pins 16 are known. Also, to fit between the uprights 10 of
the cart 1', the gripping part 70 has a size which corresponds
substantially with the size of a shelf 4.
[0046] With reference to FIGS. 5 and 6, an approved shelf 4 is
gripped by the robot arm 40 from the testing section 24, firstly by
a short movement C upwardly over the frame 35. Subsequently or
simultaneously, the shelf 4 is tilted D over an angle of 20
degrees. In this position, enough room arises to move the shelf 4
forward E between the uprights 10 of the waiting cart 1'. In a
first lateral movement F, the pins 16 are fitted into the slots 12
on the lowest edge. Subsequently, by tilting back G and a second
lateral movement H of the shelf 4, the other pins 16 are fitted
into their slots 12. By avoiding as much as possible vertical
movements of the shelf 4, the transfer from the testing section to
the frame can be performed in less than 7 seconds.
[0047] Thus, the invention has been described by reference to
certain embodiments discussed above. It will be recognized that
these embodiments are susceptible to various modifications and
alternative forms well known to those of skill in the art.
[0048] Further modifications in addition to those described above
may be made to the structures and techniques described herein
without departing from the spirit and scope of the invention.
Accordingly, although specific embodiments have been described,
these are examples only and are not limiting upon the scope of the
invention.
* * * * *