U.S. patent application number 17/431364 was filed with the patent office on 2022-05-05 for underwater propulsion device removably fixed to a flipper.
The applicant listed for this patent is Wawken AB. Invention is credited to Bengt STENEBY.
Application Number | 20220134187 17/431364 |
Document ID | / |
Family ID | |
Filed Date | 2022-05-05 |
United States Patent
Application |
20220134187 |
Kind Code |
A1 |
STENEBY; Bengt |
May 5, 2022 |
UNDERWATER PROPULSION DEVICE REMOVABLY FIXED TO A FLIPPER
Abstract
Underwater propulsion device (10, 110) comprising a propulsion
unit (11, 111) and a mounting unit (12, 112). The propulsion unit
is mounted to the mounting unit and comprises an electrically
driven propeller (15). The mounting unit (12, 112)is arranged to be
removably fixed to a diving flipper (1).
Inventors: |
STENEBY; Bengt; (Partille,
SE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Wawken AB |
Gothenburg |
|
SE |
|
|
Appl. No.: |
17/431364 |
Filed: |
February 18, 2020 |
PCT Filed: |
February 18, 2020 |
PCT NO: |
PCT/SE2020/050188 |
371 Date: |
August 16, 2021 |
International
Class: |
A63B 35/12 20060101
A63B035/12; A63B 31/11 20060101 A63B031/11 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 21, 2019 |
SE |
1950221-0 |
Claims
1. Underwater propulsion device (10, 110) comprising a propulsion
unit (11, 111) and a mounting unit (12, 112), wherein the
propulsion unit is mounted to the mounting unit and comprises an
electrically driven propeller (15) and wherein the mounting unit
(12, 112) is arranged to be removably fixed to a diving flipper
(1).
2. Underwater propulsion device according to claim 1, wherein the
mounting unit (12, 112) comprises two legs (18, 19, 118a, 119a),
each leg being arranged to at least partly surround and to contact
a respective longitudinal side rib (4, 5) of the diving flipper
(1).
3. Underwater propulsion device according claim 2, wherein the
mounting device (12, 112) comprises at least one resilient member
(20, 21, 118, 119) arranged to urge said legs (18, 19, 118a, 119a)
into contact with the respective longitudinal side rib (4, 5).
4. Underwater propulsion device according to claim 2, wherein the
mounting unit (12, 112) comprises at least one support member (23,
123) arranged to bear against the diving flipper (1), at a side
(1a) which is opposite to the side (1b) to which the legs (18, 19,
118c, 119c) are urged into contact with the longitudinal side ribs
(4, 5).
5. Underwater propulsion device according to claim 2, wherein the
mounting unit (12, 112) comprises a base (17, 117) having a front
end (17b, 117b), a rear end (17a, 117b), an upper side (17d, 117d)
and a lower side (17c, 117c), the propulsion unit (11) being fixed
to the upper side (17b, 117b) of the base (17, 117), and wherein
the two legs (18, 19, 118c, 119c) are arranged to extend downwardly
from a respective lateral side edge of the base (17, 117).
6. Underwater propulsion device according to claim 1, comprising a
quick release fastener (23) which comprises a first part (23a)
which is arranged to be permanently fixed to the diving flipper (1)
and a second part (23b) which is fixed to the mounting unit (12),
wherein the first (23a) and second (23b) parts comprise cooperating
locking means.
7. Underwater propulsion device according to claims 5, wherein said
second part (23b) is hingedly connected to the base (17).
8. Underwater propulsion device according to claim 3, wherein the
at least one resilient member comprises a leaf spring (20, 21).
9. Underwater propulsion device according to claim 3, wherein the
at least one resilient member comprises a torsional spring (118,
119) formed integral with one of said legs (118c, 119c).
10. Underwater propulsion device according to claim 2, wherein the
legs (18, 19) and/or the support member (123) are provided with a
low friction material for decreasing the friction between the legs
(18, 19) and the longitudinal side ribs (4, 5).
11. Underwater propulsion device according to claim 2, wherein the
legs (118c, 119c) are provided with a high friction material (118e,
119e) for increasing the friction between the legs and the
longitudinal side ribs (4, 5) of the diving flipper.
Description
TECHNICAL FIELD
[0001] The present disclosure relates to the field of assisted
propulsion at swimming and diving and in particular to an
electrified underwater propulsion device for use with diving
flippers also called swim fins.
BACKGROUND
[0002] Swimming and diving in water requires quite large amounts of
energy. It is tiring and, for scuba divers, under water
transportation increases the oxygen consumption which in turn
reduces the time that the diver may stay under the surface. Scuba
and snorkel divers as well as regular on-surface swimmers often use
diving flippers or swim fins for facilitating the transportation
and to increase the speed.
[0003] There have also been developed several different motorised
propulsion devices intended to assist at in- and underwater
transportation. Some such known propulsion devices are hand held
which reduces the diver's ability to use the hands for other
purposes. Some other are designed to be fastened to the torso, the
arms or the legs of the diver/swimmer. The latter devices often are
bulky and impede manoeuvrability and quick directional changes.
[0004] U.S. Pat. No. 6,341,993 B1 discloses an underwater
propulsion device constituted by a motorized swim fin. The device
comprises a boot with a paddle extending from a toe portion of the
boot. A tubular passageway way is arranged in the paddle and a
power driven shaft with a propeller is arranged in the passageway
for pushing water from an inlet to an outlet of the passageway.
SUMMARY
[0005] One object of the present disclosure is to provide an
enhanced underwater propulsion device.
[0006] Another object is to provide such a propulsion device which
may be used with standard diving flippers.
[0007] A further object is to provide such a propulsion device
which readily may be mounted to a traditional diving flipper.
[0008] Yet another object is to provide such a propulsion device
which allows easy dismounting from the diving flipper for using the
flipper in a traditional manner.
[0009] A still further object is to provide such a propulsion
device which allows the flipper to be used in a traditional manner
also when the propulsion device is mounted thereto.
[0010] Another object is to provide such a propulsion device which
allows good manoeuvrability as well as quick and easy directional
changes.
[0011] A further object is to provide such a propulsion device
which is simple in its construction and which may be manufactured
at a comparatively low cost.
[0012] These and other objects are achieved by an underwater
propulsion device as set out in appended claim 1. The underwater
propulsion device comprises a propulsion unit and a mounting unit.
The propulsion unit is mounted to the mounting unit and comprises
an electrically driven propeller. The mounting unit is arranged to
be removably fixed to a diving flipper.
[0013] The underwater propulsion device being mountable to a
regular or standard diving flipper affords for a number of
advantages. Divers and swimmers normally have their own flippers
which have been selected with great care for optimal performance
and comfort. Parameters which are taken into consideration when
choosing the best flippers include the size of the portion holding
the foot, the length and other dimensions of the paddle. The
material of the foot and paddle portions as well as its stiffness
and flexibility are important. The colour and other design features
of the flipper are often also taken into consideration. Hence both
for professional divers and for hobbyists it is important that the
diving flippers are carefully selected and there exist a great
variety of different variants in order to suit every diver's needs
and taste. The mountable propulsion device of this disclosure thus
allows for that the user may still use his/her favourite flippers
while adding on an additional motorized propulsion
functionality.
[0014] Additionally, rental shops for water sports equipment need
only to keep a limited number of identical propulsion devices in
stock. A pair of these may then be combined with any of the
different diving flippers already in stock or with the rental
customer's own flippers, in order to offer the best combination for
each customer. This allows for an important saving of costs for the
shop owner and, in the end, also for the rental customer.
[0015] The fact that the propulsion device, in use, is mounted to
the diving flippers also allows for that the user may use his or
her hands for other purposes than holding the propulsion device. It
has also proven that such mounting to the flippers greatly improves
the manoeuvrability and the ability to quickly change direction in
comparison to previous underwater propulsion devices which are hand
held or attached to the torso, the arms or the legs of the
user.
[0016] The mountable propulsion device according to the present
disclosure may be designed and constructed essentially less
complicated and with fewer constituent components in comparison
with the motorized swim fin according to U.S. Pat. No. 6,341,993
B1. This greatly reduces the time and cost needed for
manufacturing.
[0017] At one embodiment the mounting unit may comprise two legs,
each leg being arranged to at least partly surround and to contact
a respective longitudinal side rib of the diving flipper. Most
diving flippers presently available on the market exhibit
stiffening longitudinal side ribs which extend along each
peripheral edge of the paddle portion, from the foot portion
towards or to the longitudinal free end of the paddle portion. The
two legs of the propulsion device's mounting unit allow for that
these ribs may be utilized for a secure removable fixation of the
device to the flipper.
[0018] The mounting device may comprise at least one resilient
member arranged to urge said legs into contact with the respective
longitudinal side rib. This facilitates the mounting operation and
enhances fixation to the flipper.
[0019] The mounting unit may comprise at least one support member
arranged to bear against the diving flipper, at a side which is
opposite to the side to which the legs are urged into contact with
the longitudinal side ribs. This further enhances the fixation.
[0020] The mounting unit may comprise a base having a front end, a
rear end, an upper side and a lower side, the propulsion unit being
fixed to the upper side of the base, and the two legs may be
arranged to extend downwardly from a respective lateral side edge
of the base. By this means a sturdy and reliable mounting unit is
achieved in a simple manner.
[0021] The underwater propulsion device may comprise a quick
release fastener which comprises a first part which is arranged to
be permanently fixed to the diving flipper and a second part which
is fixed to the mounting unit, wherein the first and second parts
comprise cooperating snap lock means. By this means, secure
fixation to the flipper is further enhanced in a simple and cost
effective manner.
[0022] Said second part may be hingedly connected to the base. Such
a hinge functionality applied to the mounting unit allows for that
the paddle portion of the flipper may flex in an almost normal
manner. This in turn enhances the ability to use the flippers in a
traditional manner whether or not the propulsion unit is
activated.
[0023] The at least one resilient member may comprise a leaf
spring. By this means the desired urging of the legs is
accomplished in a reliable and simple manner.
[0024] Alternatively or in combination, the at least one resilient
member may comprise a torsional spring formed integral with one of
said legs. This allows for alternative embodiments and enhances the
fixation of the propulsion device.
[0025] The legs and/or the support member may be provided with a
low friction material for decreasing the friction between the legs
and the longitudinal side ribs. At some embodiments this may
increase the flipper's ability to flex in a normal manner, thereby
enhancing traditional use of the flippers.
[0026] Alternatively the legs may be provided with a high friction
material for increasing the friction between the legs and the
longitudinal side ribs of the diving flipper. At some embodiments
such increased friction may enhance the fixation of the legs to the
ribs while still allowing the flipper's paddle portion to flex
normally.
[0027] Further objects and advantages of the underwater propulsion
device will appear from the following detailed description and the
appended claims.
[0028] Generally, all terms used in the claims are to be
interpreted according to their ordinary meaning in the technical
field, unless explicitly defined otherwise herein. All references
to "a/an/the element, apparatus, component, means, step, etc." are
to be interpreted openly as referring to at least one instance of
the element, apparatus, component, means, step, etc., unless
explicitly stated otherwise. The steps of any method disclosed
herein do not have to be performed in the exact order disclosed,
unless explicitly stated.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] Aspects and embodiments are now described, by way of
example, with reference to the accompanying drawings, in which:
[0030] FIG. 1a is a top view of a traditional diving flipper which
may be used with the underwater propulsion device. FIG. b is a
section along A-A in FIG. 1a.
[0031] FIG. 2 is a side view of an underwater propulsion device
according to a first embodiment when mounted to a diving flipper
worn by a user.
[0032] FIG. 3 is a front view of the underwater propulsion device
shown in FIG. 1.
[0033] FIG. 4 is a top view of the underwater propulsion device
shown in FIG. 1.
[0034] FIG. 5 is a top view of an underwater propulsion device
according to a second embodiment when mounted to a diving
flipper.
[0035] FIG. 6 is a side view, partly in section along B-B in FIG. 5
of the underwater propulsion device shown in FIG. 5.
[0036] FIG. 7 is a side view of the underwater propulsion device
shown in FIG. 5.
[0037] FIG. 8 is a front view of the underwater propulsion device
shown in FIG. 5.
[0038] FIG. 9 is a top view of the underwater propulsion device
shown in FIG. 5.
DETAILED DESCRIPTION
[0039] The aspects of the present disclosure will now be described
more fully hereinafter with reference to the accompanying drawings,
in which certain embodiments of the invention are shown.
[0040] These aspects may, however, be embodied in many different
forms and should not be construed as limiting; rather, these
embodiments are provided by way of example so that this disclosure
will be thorough and complete, and to fully convey the scope of all
aspects of the invention to those skilled in the art. Like numbers
refer to like elements throughout the description.
[0041] FIG. 1a illustrates a conventional diving flipper 1 or swim
fin. The diving flipper has an upper side 1a shown in FIG. 1a and
an opposite lower side 1b. It comprises a rear foot portion 2 with
a cavity 2a for receiving a foot of the user. The foot portion 2a
exhibits a front opening 2b through which the toes of the wearer
protrudes. A paddle portion 3 extends forwardly to a free end 3a
from the foot portion 2. The width of the paddle portion 3
increases from the foot portion 2 towards the free end 3a. A
stiffening rib 4, 5 extends longitudinally along each peripheral
side of the paddle portion 3. The ribs 4, 5 extend from essentially
a mid section of the foot portion 2 to the free end 3a. Since the
width of the paddle portion 3 increases in the forward direction,
the ribs 4, 5 diverge in the forward direction. The vertical
thickness of the ribs 4, 5 varies along the longitudinal length,
such that is exhibits a maximum at a longitudinal mid portion and a
minimum at the respective longitudinal ends. The ribs 4, 5 are
essentially thicker than the intermediate portion of the paddle
portion 3, arranged between the ribs 4, 5, such that the ribs
protrude upwardly and downwardly from this intermediate portion.
The diving flipper 1 is made of a flexible material such as rubber.
The foot portion 2 is essentially softer and more flexible that the
paddle portion 3, such that the walls surrounding the cavity 2a may
be depressed. Even though the paddle portion 3 is stiffer than the
foot portion 2, it flexes upwards and downwards when the user
paddles his or her feet during transportation in the water.
[0042] A first embodiment of the underwater propulsion device 10
will now be described with reference to FIGS. 2a-4. The propulsion
device 10 comprises a propulsion unit 11 and a mounting unit 12
arranged to be mounted to a diving flipper 1 of the general kind
illustrated in FIGS. 1a, 1b. The propulsion unit 11 comprises a
cylindrical housing 13 which receives an electrical motor 14 having
a propeller 15 fixed on its rotating axle (not shown). In the
figures the propulsion unit 11 is schematically illustrated. It
also comprises not shown means for fixing the motor 14 to the
housing 13. An electrical cable 16 which is connected to the motor
for power supply and control extends from the propulsion unit 11.
The cable is also connected to a power supply (not shown) such as a
rechargeable battery pack which may be worn e.g. at the leg or
torso of the user and to a control device (not shown) which e.g.
may be integrated with the battery pack or which may be worn at an
arm, wrist or hand of the user. Alternatively, the control unit may
be wirelessly connected to the motor. At a further alternative the
battery pack may be fixed to or made integral with the propulsion
unit or the mounting unit. When such embodiments are combined with
a wireless control unit an important advantage of not requiring any
external cables is achieved. The propulsion unit may however be
realized in many different manners, as readily realized by the
person skilled in the art.
[0043] The propulsion unit 11 is fixed to the upper side of the
mounting unit 12. The mounting unit 12 comprises a plate shaped
base 17. The base 17 has a rear end 17a, a front end 17b, a lower
side 17c facing the flipper 1 when mounted and an opposite upper
side 17d. A pair of legs 18, 19 extend downwardly from a respective
and mutually opposite side edge of the base 17, at its rear end
17a. As best seen in FIG. 3, each leg 18, 19 comprises a downwardly
projecting stem 18a, 19a and a curved, inwardly projecting lug 18b,
19b. The legs 18, 19 are connected to the base 17 by a respective
curved connecting portion 18c, 19c. The lugs 18b, 19b and the
connecting portions 18c, 19c are arranged to receive and partially
surround a respective rib 4, 5 of the flipper 1.
[0044] The mounting unit 12 further comprises two resilient
members, here in the form of leaf springs 20, 21. One end of each
leaf spring is fixed to the lower side of the base 17, centrally
and in proximity to the rear end 17a. The leaf springs 20, 21
extend downwardly and outwardly towards a respective leg 18, 19.
The leaf springs 20, 21 are arranged to exert a downward force when
compressed upwardly.
[0045] The mounting unit 12 also comprises a hinge mechanism 22
arranged at the front end 17b of the base 17. A support member
formed by a quick release fastener 23 is hingedly connected to the
base 17 by means of the hinge mechanism 22. The quick release
fastener 23 comprises a first part 23a which is arranged to be
permanently fixed to the paddle portion 3 of the flipper 1 and a
second part 23b which is hingedly connected to the base 17. The
first part may e.g. be fixed to the paddle portion 3 by gluing.
Alternatively or in combination the first part may comprise a first
sub-part comprising a treaded stem and a circular flange and a
second sub-part comprising a circular disc with a threaded hole for
receiving the stem. For fixing the first part 23a to the paddle
portion 3, the stem is pushed or screwed from below to penetrate
the paddle portion until the flange contacts the lower side of the
paddle portion and the stem protrudes above the upper side of the
paddle portion. Thereafter the disc is screwed onto the stem for
fixing the first part to the paddle portion 3. The first 23a and
second 23b parts are arranged to be mutually connected by being
pushed together and disconnected by pulling a knob on the second
part 23b. Such quick release fasteners are well known in the art.
One example which may be used is sold under the trade name
LOXX.RTM. but other quick release fasteners may also be used.
[0046] Mounting of the underwater propulsion device 10 to the
diving flipper 1 will now be explained. First the base 17 is slided
onto the diving flipper, from the narrower rear foot portion
forwardly. The flexible walls surrounding the cavity 2a, are then
compressed such that the mounting unit 12 may be advanced with the
two legs 18 sliding along the ribs 4, 5. The mounting unit 12 is
displaced forwardly until the legs 18, 19 have passed the foot
portion 2 and have reached a portion of the paddle portion 3
approximately where the ribs 4, 5 exhibit the largest vertical
thickness. At this position, the first part 23a of the quick
release fastener 23 is fixed to the paddle portion 3 of the flipper
1, as described above. The second part 23b of the quick release
fastener 23 is then aligned with the first part 23a and the two
parts 23a, 23b may be pushed together for mutual fixation. The
mounting unit 12 has now assumed its correct mounting position on
the diving flipper 1. In this position, the leaf springs 20, 21 are
compressed and their free ends make contact with the upper side 1a
of the paddle portion 3. The force exerted by the leaf springs 20,
21 urges the lugs 18b, 19b into contact with the lower edges of a
respective rib 4, 5 Thereby, the mounting unit 12 has been securely
mounted to the diving flipper 1.
[0047] In use at forward transportation, the diver stretches
his/her ankles such that the rotational axis of the motor 14 is
directed generally in parallel with the user's longitudinal
direction. The propeller 15 then pushes water backwardly to thereby
propel the user forwardly. For turning in either sideways
direction, upwards or downwards the user may easily angel his/her
feet in a corresponding direction for excellent and quick control
of the transportation direction. Activation, deactivation and speed
control of the motor is readily achieved e.g. by pushing
corresponding push buttons on the control device (not shown).
[0048] Whether or not the motor is activated, the user may also use
the diving flippers 1 in a ordinary manner by paddling his/her
feet. The water resistance will then urge the paddle portions to
flex upwardly and downwardly from the position shown in FIG. 2.
Such flexing is allowed grace to the hinge mechanism 22 and the
ability of the legs 18, 19 and the lugs 18b, 19b to slide along the
respective rib 4, 5. For increasing this sliding function and
enhancing flexing of the paddle portion 3, the lugs 18b, 19b and/or
the stems 18a, 19a of the legs 18, 19 may be formed of or comprise
a low friction material such as polyethylene (PE),
polytetrafluoroethylene (PTFE) or the like
[0049] A second embodiment will now be described with reference to
FIGS. 5-9. Also at this embodiment the underwater propulsion device
100 comprises a propulsion unit 111 which is fixed to the upper
side of a mounting unit 112. The propulsion unit 111 is identical
with the propulsion unit according to the first embodiment and it
is not described further here.
[0050] The mounting unit 112 comprises a generally plate shaped
base 117 having a rear end 117a, a front end 117b, a lower side
117c and an upper side 117d. At the front end 117b, the base
exhibits a downwardly protruding curved support member 123 arranged
to make contact with the upper side of the paddle portion 3 of the
flipper 1. The support member 123 may be formed of or comprise a
low friction material for enhancing sliding of the support member
123 relative to the paddle portion 3. The curvature of the support
member 123 also contributes to decreasing the friction. At its rear
end 117a, the base exhibits two tubular spring holders 122a, 122b,
arranged at a respective side edge of the base 117. Each spring
holder 122a, 122b receives a torsional spring 118, 119.
[0051] Each torsional spring 118, 119 comprises a first support
section 118a which is supported on the upper side 117d of the base
117. A torsional section 118b, 119b extends perpendicularly
outwards from the rear end of the respective support section 118a,
119a and is received in and held by the tubular spring holder 122a,
122b. Each torsional spring further comprises a leg 118c, 119c
which extends perpendicularly from the outer end of the respective
torsional section 118b, 119b. As represented by solid lines in FIG.
7, the legs 118c, 119c are arranged generally in parallel with the
support sections 118a, 119a when the torsional springs 118, 119 are
relaxed. At the free end of each leg 118c, 119c, a lug 118d, 119d
projects inwardly. Each lug 118d, 119d comprises a bent portion of
the spring 118, 119 and a sleeve 118e, 119e which receives the bent
portion. The sleeves 118e, 119e may be formed of or comprise a high
friction material for preventing relative movement between the
holding unit 112 and the paddle portion 3 when mounted.
[0052] The base further comprises two downwardly projecting contact
tabs 124a, 124b. The contact tabs 124a, 124b may be formed sharp
such that they penetrate somewhat into the upper side of the paddle
portion for secure fixation of the holding unit 112 to the paddle
portion 3. In the latter case it may be desirable to minimize the
friction between the lugs 118d, 119d and the ribs 4, 5. The sleeves
118e, 119e may then comprise a low friction material and/or be
arranged rotatable relative to the bent portions.
[0053] When mounting the underwater propulsion device 100 to the
diving flipper 1, the, the legs 118c, 119c are first tensioned by
pivoting the legs 118c, 119c downwards and backwards as indicated
by the dashed lines in FIG. 7. Thereafter the holding unit is slid
onto the flipper 1 from behind. As at the first embodiment, the
flexibility of the walls enclosing the cavity 2a allows the holding
portion with the base 117, the legs 118c, 119c and the lugs 118d,
119d to pass the foot portion 2 of the flipper. When the mounting
unit has reached the position illustrated in FIGS. 5 and 6, where
the legs are arranged generally at a position where the ribs 4, 5
exhibit their largest vertical thickness, the legs 118c, 119c are
released. The spring force will then urge the legs 118c, 119c,
forwardly such that the lugs 118d, 119d are pressed against the
lower edge of the ribs 4, 5. Simultaneously the contact tabs 124a,
124b are pressed against the upper side of the paddle portion and
if the are sharp, they may somewhat penetrate into the upper
surface of the paddle portion 3. The torsional spring force will
also exert a torque onto the base 117 such that the support member
123 is pressed in to contact with the upper side of the paddle
portion. By this means the underwater propulsion device according
to the second embodiment has been securely fixed to the diving
paddle.
[0054] The propulsion device according to the second embodiment is
activated, deactivated, controlled and maneuvered generally in the
same manner as the propulsion deice according to the first
embodiment.
[0055] When the flippers 1 are to be used in a traditional manner,
with the propulsion devices mounted, the resiliency of the
torsional spring allows the base to pivot somewhat around the
contact tabs 122a, 122b relative to the paddle portion. This in
combination with that the support member 123 is arranged to slide
on the upper surface of the paddle portion 3 allows the paddle
portion 3 to flex upwardly and downwardly during paddling of the
users feet.
[0056] In both the above described embodiments the base may be
formed of stainless steel, plastic or any other suitable
material.
[0057] The resilient member may comprise a helical compression
spring or any other suitable resilient member or material, instead
of or in combination with a leaf spring or a torsion spring as
described above.
[0058] In the examples shown and described above the diving flipper
or swim fin is of the type comprising a cavity arranged to receive
a foot of the user. Naturally however the flipper may be of other
types, e.g. having a heel strap which is tightened around the heel
of the user. It is also possible to use the propulsion device
together with so called solo flippers where both feet of the user
are fixed to a single paddle.
[0059] The aspects of the present disclosure have mainly been
described above with reference to a few embodiments and examples
thereof. However, as is readily appreciated by a person skilled in
the art, other embodiments than the ones disclosed above are
equally possible within the scope of the invention, as defined by
the appended patent claims.
* * * * *