U.S. patent application number 12/599203 was filed with the patent office on 2010-12-09 for three part tube.
This patent application is currently assigned to ELECTROLUX. Invention is credited to Stefan Jonsson, Andreas Pohl, Esbjorn Svantesson, Henrik Troberg, Anna-Karin Trydegard.
Application Number | 20100306960 12/599203 |
Document ID | / |
Family ID | 39943736 |
Filed Date | 2010-12-09 |
United States Patent
Application |
20100306960 |
Kind Code |
A1 |
Jonsson; Stefan ; et
al. |
December 9, 2010 |
THREE PART TUBE
Abstract
This invention relates to a telescopic vacuum cleaner tube
comprising a first inner tube, a second inner tube, and an outer
tube, wherein the first and second inner tubes are arranged to form
first and second telescopic links relative to first and second end
portions of the outer tube, respectively. The outer tube forms the
intermediate tube of the three-part tube while at the same time
being fully accessible in any position, whereby one common grip for
operating both of the two respective telescopic links, formed by
the first and second inner tubes and the intermediate outer tube,
of the three part telescopic tube is obtained.
Inventors: |
Jonsson; Stefan; (Stockholm,
SE) ; Trydegard; Anna-Karin; (Stockholm, SE) ;
Svantesson; Esbjorn; (Taby, SE) ; Pohl; Andreas;
(Bromma, SE) ; Troberg; Henrik; (Segeltorp,
SE) |
Correspondence
Address: |
HUNTON & WILLIAMS LLP;INTELLECTUAL PROPERTY DEPARTMENT
1900 K STREET, N.W., SUITE 1200
WASHINGTON
DC
20006-1109
US
|
Assignee: |
ELECTROLUX
Stockholm
SE
|
Family ID: |
39943736 |
Appl. No.: |
12/599203 |
Filed: |
April 23, 2008 |
PCT Filed: |
April 23, 2008 |
PCT NO: |
PCT/SE2008/000284 |
371 Date: |
August 18, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60938367 |
May 16, 2007 |
|
|
|
Current U.S.
Class: |
15/414 |
Current CPC
Class: |
A47L 9/244 20130101 |
Class at
Publication: |
15/414 |
International
Class: |
A47L 9/02 20060101
A47L009/02 |
Foreign Application Data
Date |
Code |
Application Number |
May 7, 2007 |
SE |
0701108-3 |
Claims
1. A telescopic tube for a vacuum cleaner, the telescopic tube
comprising: an outer tube; a first inner tube slidably arranged
inside the outer tube and selectively lockable in at least one
first tube position relative to the outer tube, the first inner
tube being arranged relative to a first end portion of the outer
tube to form a first telescopic link with the outer tube such that
the first inner tube is extendable from the first end portion; and
a second inner tube slidably arranged inside the outer tube and
selectively lockable in at least one second tube position relative
to the outer tube, the second outer tube being arranged relative to
a second end portion of the outer tube to form a second telescopic
link with the outer tube such that the second inner tube is
extendable from the second end portion.
2. The telescopic tube for a vacuum cleaner according to claim 1,
wherein: the first inner tube and the first end portion of the
outer tube are arranged with a first releasable locking member; and
the second inner tube and the second end portion of the outer tube
are arranged with a second releasable locking member.
3. The telescopic tube for a vacuum cleaner according to claim 2,
further comprising a control mechanism for controlling the first
and second locking members,
4. The telescopic tube for a vacuum cleaner according to claim 4,
wherein the control mechanism comprises an interconnecting part
between the first locking member and the second locking member,
wherein the first and second locking members are simultaneously
controllable by the interconnecting part.
5. The telescopic tube for a vacuum cleaner according to claim 4,
wherein the control mechanism is arranged on the outer tube.
6. The telescopic tube for a vacuum cleaner according to claim 5,
wherein the interconnecting part comprises a shell surface arranged
over and along the outer tube.
7. The telescopic tube for a vacuum cleaner according to claim 6,
wherein the outer tube comprises a generally cylindrical outer tube
surface, and the interconnecting part generally comprises a partial
cylinder surface overlying the outer tube surface.
8. The telescopic tube for a vacuum cleaner according to claim 2,
wherein the first and second locking members are arranged to be
released when receiving a longitudinally directed force in excess
of a predefined threshold force.
9. The telescopic tube for a vacuum cleaner according to claim 3,
wherein the first and second locking members are arranged to be
released when receiving a longitudinally directed force in excess
of a predefined threshold force.
10. The telescopic tube for a vacuum cleaner according to claim 4,
wherein the first and second locking members are arranged to be
released when receiving a longitudinally directed force in excess
of a predefined threshold force.
11. The telescopic tube for a vacuum cleaner according to claim 3,
wherein the control mechanism includes a releasable locking device,
for releasing and locking the first and second locking members.
12. The telescopic tube for a vacuum cleaner according to claim 1,
wherein the outer tube has a larger diameter than the first inner
tube and the second tube, and the second inner tube has a larger
diameter than the first inner tube.
13. The telescopic tube for a vacuum cleaner according to claim 1,
wherein the position of at least one of the first inner tube and
the second inner tube relative to the outer tube is continuously
adjustable.
14. The telescopic tube for a vacuum cleaner according to claim 1,
wherein the position of at least one of the first inner tube and
the second inner tube relative to the outer tube is stepwise
adjustable.
15. The telescopic tube for a vacuum cleaner according to claim 1,
wherein at least one of the first inner tube and the second inner
tube is connectable to a vacuum cleaner nozzle.
16. The telescopic tube for a vacuum cleaner according to claim 1,
wherein at least one of the first inner tube and the second inner
tube is connectable to a vacuum cleaner housing or to a flexible
tube.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a telescopic tube for a
vacuum cleaner, and more particularly to a three part telescopic
tube.
BACKGROUND OF THE INVENTION
[0002] The idea of using telescopic tubes to be able to adjust the
length of a vacuum cleaner tube is known. One advantage with
telescopic vacuum cleaner tubes is to be able to optimize the tube
length for a specific cleaning task or for the height of a person
that is using the vacuum cleaner. Telescopic tubes also provide the
benefit of minimizing the length of the tube when not in use, thus
facilitated storage is provided.
[0003] The basic concept of telescopic tubes is to have an inner
tube that is movably arranged within an outer tube. The tubes are
further provided with a locking member, for instance a simple form
of recess and engagement means that is released by means of a
control mechanism, for instance by pressing down a release button,
while the user pushes or pulls out the movable tube with respect to
the outer tube. When the required length of the tube has been
reached the locking member keeps the inner tube in position.
[0004] Telescopic tubes comprising three tubes joined with two
telescopic links in the same unit are available on the market
today. With two telescopic links a telescopic tube, which can be
minimized in respect to its maximum length, i.e. when the two
movable tubes are fully extended, is obtained. The two telescopic
links are controlled by two separate control mechanisms, each
controlling one individual telescopic link. A problem with this
known three-part telescopic tube is that the adjusting the length
of the tube by operating the telescopic links can be experienced as
troublesome.
SUMMARY OF THE INVENTION
[0005] It is one object of the present invention to provide a three
part telescopic tube for a vacuum cleaner that alleviates the
above-mentioned problem of the prior art. This object may be
achieved by a telescopic tube for a vacuum cleaner according to the
present invention as defined in claim 1.
[0006] Thus, in accordance with an aspect of the present invention,
there is provided a telescopic tube for a vacuum cleaner,
comprising a first inner tube, a second inner tube, and an outer
tube. The first and second inner tubes are slidably arranged inside
the outer tube and the first and second inner tubes are lockable
relative the outer tube. The first inner tube is arranged relative
to a first end portion of the outer tube to form a first telescopic
link with the outer tube such that the first inner tube is
extendable from the first end portion. The second inner tube is
arranged relative to a second end portion of the outer tube to form
a second telescopic link with the outer tube such that the second
inner tube is extendable from the second end portion.
[0007] Thus, there is provided a three-part telescopic tube for a
vacuum cleaner, where the outer tube encompasses two inner tubes
that each are arranged to form a telescopic link at a respective
end of the outer tube. Hence, the outer tube forms the intermediate
tube of the three-part tube while it at the same time is fully
accessible in any position: the fully extended position, the fully
retracted position or any intermediate position between these
positions. Thus both tubes are easily accessible at their
respective ends at all times, and the total length of the tube is
easily adjustable.
[0008] In accordance with an embodiment of the telescopic tube for
a vacuum cleaner as defined in claim 2, the first inner tube and
the first end portion of the outer tube are arranged with a first
releasable locking member, and the second inner tube and the second
end portion of the outer tube are arranged with a second releasable
locking member. Due to the releasable locking members, the tubes
can be securably locked relative each other in a locking position
of the locking members and easily movable relative each other in a
released position of the locking members.
[0009] In accordance with the telescopic tube for a vacuum cleaner,
as defined in claim 3, the telescopic functions of the two
respective telescopic links can be easily controlled by a control
mechanism for the locking members, which control mechanism is
arranged on the outside of the outer tube.
[0010] In accordance with the telescopic tube for a vacuum cleaner
as defined in claim 4, the control mechanism is arranged to control
the first and second locking members simultaneously.
[0011] This exemplary embodiment of the invention provides a
telescopic three-part tube, that has two telescopic links that are
controlled with only one control mechanism that is arranged to
control the first and second locking members simultaneously. The
telescopic tube is thereby allowed to be operated from retracted to
extended positions by a one grip operation, which may simplify the
length adjustment of the telescopic tube. Using one control
mechanism also may simplify the construction complexity compared
with prior three-part tubes, i.e. fewer parts can be used, and thus
the manufacturing costs of the tube can be decreased.
[0012] In accordance with an embodiment of the telescopic tube for
a vacuum cleaner the control mechanism comprises an interconnecting
part between the first locking member and the second locking
member, which is favourable for allowing simultaneous control of
the first and second locking member.
[0013] In accordance with an embodiment of the telescopic tube for
a vacuum cleaner as defined in claim 5, the interconnecting part is
at least a part of a cylinder shell surface encompassing the outer
tube. Since the outer tube is accessible in all position it allows
for a common grip when extending and/or retracting the first and
second telescopic links. The interconnecting part may be an
integrated part of the outer tube.
[0014] In accordance with an embodiment of the telescopic tube for
a vacuum cleaner as defined in claim 6, the first locking member
and the second locking member are arranged to be released when
receiving a longitudinally directed force in excess of a predefined
threshold force. Hence, the operation of the telescopic tube is
user friendly. The user only has to hold the outer tube with one
hand and push or pull the inner tubes with the other hand to change
the inner tube positions. According to an example embodiment, it is
even possible to extend or retract the first and second inner tubes
at the same time by using a third support, e.g. one foot on the
suction nozzle, to hold one end of the telescopic tube and then
push or pull the tubes in the required direction.
[0015] In accordance with an embodiment of the telescopic tube for
a vacuum cleaner as defined in claim 7, the control mechanism
includes a releasable locking device for releasing the first and
second locking members allowing the repositioning of the inner
tubes to a required position. When deactivating the locking device
and after reaching the new required position, the locking device
then locks the telescopic tube in the new position.
[0016] In accordance with an embodiment of the telescopic tube for
a vacuum cleaner as defined in claim 8, the outer tube has a larger
diameter than the first inner tube and the second inner tube, and
the second inner tube has a larger diameter than the first inner
tube. Thus, the first inner tube can be retracted into the second
inner tube, which in turn can be retracted into the outer tube.
This allows for achieving a reduced length of the telescopic tube
in the fully retracted position. Thus, valuable space can be saved
when storing the tube.
[0017] In accordance with an embodiment of the telescopic tube for
a vacuum cleaner as defined in claim 9, the position of the inner
tubes relative to the outer tube is continuously adjustable, thus
making it possible for the user to make a precise adjustment of the
length to fit to his or her own height or to some other required
criteria, like for instance required radial range of the vacuum
cleaner tube.
[0018] In accordance with an embodiment of the telescopic tube for
a vacuum cleaner as defined in claim 10, the position of the inner
tubes relative to the outer tube is stepwise adjustable, allowing
fixed preferred positions of the telescopic tube.
[0019] In accordance with an embodiment of the telescopic tube for
a vacuum cleaner as defined in claim 11, at least one of the first
and second inner tubes is connectable to a vacuum cleaner nozzle.
According to an exemplary embodiment, wherein the first inner tube
has a smaller diameter than the second inner tube, it may be more
favorable to connect the vacuum cleaner nozzle to the first inner
tube than the second inner tube. Due to the first inner tube having
a smaller diameter than the second inner tube, the air steam will
flow from a smaller diameter tube to a greater diameter tube,
reducing the risk that dust particles in the air stream will clog
the tube or that larger debris will get stuck further up the tube.
Furthermore, placing the first inner tube with the smallest
diameter closest to the vacuum cleaner nozzle may be favorable to
the weight distribution of the vacuum cleaner tube, and may make
the telescopic tube easier to manoeuvre.
[0020] In accordance with an embodiment of the telescopic tube for
a vacuum cleaner as defined in claim 12, at least one of the first
and second inner tubes is connectable to a vacuum cleaner housing
or a flexible tube. The telescopic tube is advantageously connected
directly to the vacuum cleaner housing or to a flexible tube,
depending on the type of vacuum cleaner. On an upright model one
end of the telescopic tube is preferably placed directly on the
vacuum cleaner housing while the other end is provided with a
handle, while on a canister model the telescopic tube is used as
the vacuuming tube and is connected to a vacuum cleaner nozzle at
one end and to a flexible tube at the other end. In an alternative
upright model the telescopic tube is used as a vacuuming tube and
is connected to a vacuum cleaner nozzle at one end, and to the
vacuum cleaner housing at the other end, as shown in FIG. 5.
[0021] These and other aspects, features, and advantages of the
invention will be apparent from and elucidated with reference to
the embodiments described hereinafter, but are not intended to
limit the scope of the claimed or disclosed invention in any
way.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The invention will now be described in more detail and with
reference to the appended drawings in which:
[0023] FIG. 1 shows schematic drawings of an embodiment of a
telescopic tube for a vacuum cleaner according to the present
invention: a) in fully extended position, b) in an intermediate
position, c) in an intermediate position, and d) in fully retracted
position;
[0024] FIG. 2 a) and b) shows cross-sectional views of an
embodiment of a telescopic tube for a vacuum cleaner according to
the present invention;
[0025] FIG. 3 a) and b) shows cross-sectional views of an
embodiment of a telescopic tube for a vacuum cleaner according to
the present invention.
[0026] FIG. 4 shows a cross-sectional view of an embodiment of a
telescopic tube for a vacuum cleaner according to the present
invention.
[0027] FIG. 5 a) and b) shows schematic drawings of embodiments of
a telescopic tube for a vacuum cleaner according to the present
invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0028] Referring to FIG. 1a), there is shown a schematic drawing of
a telescopic tube for a vacuum cleaner 10 according an embodiment
of the present invention. The telescopic tube 10 comprises a first
inner tube 11, herein after referred to as the lower tube 11, a
second inner tube 12, herein after referred to as the upper tube
12, and an outer tube 13. The upper tube 12 is arranged to be
longitudinally movable inside the outer tube 13, while the lower
tube 11 is arranged to be longitudinally movable inside the upper
tube 12 and the outer tube 13. Hence, the outer tube 13 can
encompass at least a portion of the upper tube 12 and at least a
portion of the lower tube 11. In this embodiment the outer tube 13
is of about the same length as, but somewhat shorter than, the
lower tube 11 and upper tube 12. Hence, the outer tube 13
contributes to a substantial part of the fully extended telescopic
tube 10, while at the same time allowing the inner tubes, 11 and
12, to be almost fully retracted into the outer tube 13. This
minimizes the length of the fully retracted position of the
telescopic tube 10 with respect to the fully extended position of
the telescopic tube 10. However, in an alternative embodiment the
length proportions of the lower tube 11, the upper tube 12 and the
outer tube 13 may be chosen differently and such alternatives are
not excluded from the scope of the invention as claimed.
[0029] The telescopic tube 10 further comprises a control mechanism
14, which is arranged at the outer tube 13, and further controls
the longitudinal movability of the upper tube 12 and the lower tube
11.
[0030] FIG. 1a) shows the telescopic tube 10 in its fully extended
position, with the upper tube 12 and the lower tube 11 in the
maximum extended position out of the outer tube 13, with only a
minor part of the total length of the upper tube 12 and the lower
tube 11 still arranged inside the outer tube 13. To manipulate the
telescopic tube 10 into a fully retracted position, the user simply
holds the outer tube 13, and hence the control mechanism 14, with a
first hand and then apply a longitudinal force onto, for instance,
the upper tube 12 with a second hand, i.e. the user holds the tube
12 and pushes it towards the outer tube 13, see FIG. 1b). The user
then holds the lower tube 11 with his second hand, while keeping
the first hand on the outer tube 13, and pushes the lower tube 11
towards the outer tube 13, see FIG. 1c). To manipulate the
telescopic tube 10 from fully retracted position, which is shown in
FIG. 1d) to fully extended position, the user simply holds the
outer tube 13, and the control mechanism 14, with a first hand and
then apply a longitudinal force on to, for instance, the upper tube
12 with a second hand, i.e. holds the tube 12 and pulls it out of
the outer tube 13. Then the user holds the lower tube 11 with his
second hand, while keeping the first hand on the outer tube 13, and
pulls the lower tube 11 out of the outer tube 13. Any intermediate
position between the fully extended position and fully retracted
position is allowed for the lower tube 11 and the upper tube
12.
[0031] In this embodiment the control mechanism is activated by
overcoming a threshold force working on each locking member, such
as described herein under.
[0032] Referring now to FIG. 2, which shows a cross-sectional view
of an embodiment of the invention, the relation between the
diameters of the three tubes 11, 12, and 13, is set so that the
outer tube 13 has a diameter that is larger than the diameter of
the upper tube 12, while the upper tube 12 has a larger diameter
than the lower tube 11. Hence, the outer tube 13 encompasses both
inner tubes, 11 and 12, when the telescopic tube 10 is in a
retracted position. A vacuum cleaner nozzle 40 preferably, as shown
in FIG. 2 b), is connected to the lower tube 11. In an alternative
embodiment of the present invention the inner tubes, 11 and 12,
have the same diameter.
[0033] The control mechanism 14, which preferably is arranged at
the outer tube 13, comprises a first locking member 15 and a second
locking member 16. The first releasable locking member 15 is
arranged at a first end portion 13a of the outer tube 13 and bears
against the lower tube 11. The first locking member 15 is arranged
to lock the position of the lower tube 11. The second locking
member 16 is arranged at a second end portion 13b of the outer tube
13 and bears against the upper tube 12. The second locking member
16 is arranged to lock the position of the upper tube 12. When the
control mechanism 14 is subjected to a longitudinally applied
force, according to the description above where retraction and
protraction of the telescopic tube was done by simply pulling or
pushing the constituent tubes 11, 12, and 13 apart or together,
respectively, the control mechanism 14 is arranged to release the
first locking member 15 and the second locking member 16
simultaneously. The longitudinally directed force must exceed a
predefined threshold force, i.e. the received force must be greater
than the force imparted onto the inner tubes, 11 and 12, by the
locking members holding the upper tube 12 and lower tube 11 in
position. When the locking members, 15 and 16, are released the
inner tubes, 11 and 12, are longitudinally movable relative to the
outer tube 13. When the control mechanism 14 is no longer subjected
to a longitudinal force, the locking members are reactivated and
lock the inner tubes 11 and 12 in position.
[0034] According other embodiments of a telescopic tube for a
vacuum cleaner, the locking members, 15 and 16, are provided as
friction devices or clamping devices (such as conical wedges or the
like) or a combination thereof. In these embodiments the positions
of the inner tubes 11, 12 relative to the outer tube 13 are
continuously adjustable. When using friction as the locking
mechanisms 15 and 16, the control mechanism 14 is preferably
designed as an integrated part of the outer tube 13 or the control
mechanism 14 is designed to simply constitute the outer tube 13. An
alternative way to manipulate the telescopic tube 10 from the fully
retracted position, which is shown in FIG. 1d) to the fully
extended position, is in this alternative embodiment that the user
holds the lower tube 11 with a first hand and then applies a force
on to the upper tube 12 with a second hand, i.e. holds the tube 12
and pulls the lower tube 11 and upper tube 12 apart.
[0035] FIGS. 3 and 4, show cross-sectional views of embodiments
according to the present invention. Hereinafter the telescopic link
for the upper tube 12 is described, but the description is valid
for the telescopic link for the lower tube 11 as well. Here, the
upper tube 12 (and lower tube 11) is provided with a guide track 20
extending along the upper tube 12, and a plurality of positioning
recesses 21 distributed along the upper tube 12. The guide track 20
is arranged to engage with a guide protrusion 30 arranged on the
locking member 16. The function of the guide protrusion 30 and the
guide track 20 is to keep the upper tube 12 from turning with
respect to the outer tube 13 and can be arranged anywhere around
the circumference of the upper tube 13. The locking member 16
further comprises a positioning protrusion 31 that is arranged to
lock the longitudinal position of the upper tube 12 by engaging
with any one of the positioning recesses 21. The locking member 16
is further provided with an M-shaped portion 37, se FIG. 4, which
is kept in position with two biasing springs 32 and 33. A
protruding portion 34 on the M-shaped portion 37 is arranged to
press against the positioning protrusion 31 which then remains
engaged with a positioning recess 21. When the control mechanism 14
is operated, according to the description above, a longitudinally
applied force in excess of a threshold force works on the control
mechanism 14, whereby one of the biasing springs 32 or 33 is
compressed and the protruding portion 34 of the M-shaped portion 37
is repositioned to release the locking member 16 (and locking
member 15) when the positioning protrusion 31 is released. When the
locking member 16 is released the upper tube 12 is movable
longitudinally relative to the outer tube 13. When the control
mechanism is no longer subjected to a force, the protruding portion
34 of the M-shaped portion 37 is repositioned to lock the locking
member 16 when the positioning protrusion 31 engages with another
positioning recess 21b, whereby the position of the upper tube 12
is fixed. In this embodiment the position of the inner tubes, 11
and 12, relative to the outer tube 13 is stepwise adjustable due to
the stepwise distribution of the positioning recesses 21.
[0036] It should be clear that the locking members can be realized
in a number of ways by any suitable well-known telescopic tube
locking means.
[0037] In an alternative embodiment, the upper, lower and outer
tubes, 11, 12, and 13, have an oval shape, hence guide tracks are
not necessary, because the shape of the tubes prevents the tubes
from rotating with respect to each other. Hence, the guide
protrusion 30 and guide track 20 can be left out of the
construction. Of course, any other suitable cross section can be
used for the tubes, for example a rectangular or a polygonal cross
section.
[0038] In an alternative embodiment of the telescopic tube for a
vacuum cleaner at least one of the inner tubes 11, 12 is arranged
to be fully detachable from the outer tube 13.
[0039] In an alternative embodiment of the telescopic tube for a
vacuum cleaner the control mechanism further includes a releasable
locking device 18, for locking the inner tube 11 and the upper tube
12 in position.
[0040] Referring now to FIG. 5, a telescopic tube 10 according to
an embodiment of the present invention is connectable to a vacuum
cleaner housing. As it can be seen in FIG. 5 a) the telescopic tube
10 is connected to the top of a vacuum cleaner housing 55 of an
upright vacuum cleaner 50. The upper tube 12 (or lower tube 11 if
the telescopic tube 10 is connected to the upright vacuum cleaner
via the upper tube 12) is here preferably provided with a handle
56, which may be fixed or detachable.
[0041] In FIG. 5 b) the upper tube 12 of a telescopic tube 10,
according to an embodiment of the present invention, is connected
to a flexible vacuum cleaner tube 70, which flexible vacuum cleaner
tube 70 is connected to a canister vacuum cleaner 60, an upright
vacuum cleaner, or a remote central vacuum. The lower tube 11 of
the telescopic tube 10 is connected to a vacuum cleaner nozzle 40.
In an alternative embodiment the telescopic tube 10 is connected to
a vacuum cleaner housing 55 in one end and a vacuum cleaner nozzle
40 in the other end as illustrated for the vacuum cleaner model
shown in FIG. 5 c).
[0042] Embodiments of a telescopic tube for a vacuum cleaner
according to the present invention have been described herein.
These should be seen as merely non-limiting examples. As understood
by a skilled person, many modifications and alternative embodiments
are possible within the scope of the invention.
[0043] It is to be noted, that for the purposes of this
application, and in particular with regard to the appended claims,
the word "comprising" does not exclude other elements or steps, and
that the words "a" and "an", do not exclude a plurality, which will
be apparent to a person skilled in the art.
* * * * *