U.S. patent number 3,909,867 [Application Number 05/505,986] was granted by the patent office on 1975-10-07 for hydraulic pressure driven rotary toothbrush.
Invention is credited to Gunnar Hogsell.
United States Patent |
3,909,867 |
Hogsell |
October 7, 1975 |
Hydraulic pressure driven rotary toothbrush
Abstract
A rotary toothbrush comprises a hand held housing and a
toothbrush interchangeably mounted on a rotary shaft journalled in
the housing. The housing has a chamber wherein a turbine wheel is
mounted for rotating the shaft when water under pressure is
supplied to the housing chamber. A manually operable control is
mounted on the housing to drive the wheel in either direction or to
stop it, and a water ejector means in the housing chamber causes a
pressure reduction in the chamber between the turbine wheel and a
water outlet for facilitating drainage of water. Channels in the
shaft supply rinsing water from the housing chamber to the
brush.
Inventors: |
Hogsell; Gunnar (S-291 65
Kristianstad, SW) |
Family
ID: |
20318596 |
Appl.
No.: |
05/505,986 |
Filed: |
September 13, 1974 |
Foreign Application Priority Data
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Sep 20, 1973 [SW] |
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7312796 |
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Current U.S.
Class: |
15/24; 433/80;
415/904; 433/132 |
Current CPC
Class: |
A61C
17/032 (20190501); A61C 17/30 (20130101); Y10S
415/904 (20130101) |
Current International
Class: |
A61C
17/30 (20060101); A61C 17/00 (20060101); A61C
17/16 (20060101); A61C 17/02 (20060101); A61C
017/02 (); A46B 013/06 () |
Field of
Search: |
;15/22R,23,24,28,29,97R
;32/26,27,28,59 ;415/503 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Roberts; Edward L.
Attorney, Agent or Firm: Kelman; Kurt
Claims
What is claimed is:
1. A rotary toothbrush comprising a housing shaped to be hand
gripped and an interchangeable brush means, a motor means operable
by hydraulic pressure mounted in the housing, a rotary shaft means
operably associated with the motor means for rotation about the
axis of the shaft means, the shaft means projecting from the
housing and the brush means being detachably mounted thereon, the
housing defining chamber means, an inlet for water under pressure
and a water outlet, whereby water supplied under pressure through
the inlet and flowing through the housing chamber means operates
the motor means and rotates the shaft means, water flow control
means arranged to control the water flow for blocking it from the
motor means, rotating the shaft means in a first direction and
reversing the rotational direction, channel means in the rotary
shaft means and the brush means in communication with the chamber
means for receiving rinsing water therefrom and conveying it to the
brush means, and means causing a pressure reduction in the housing
chamber means between the motor means and the water outlet for
assisting drainage of waste water from the motor means.
2. The rotary toothbrush of claim 1, wherein the hydraulic pressure
operable motor means comprises a turbine wheel having a plurality
of vanes and arranged for rotation in reversible direction, a shaft
extending through the housing, the turbine wheel being keyed to the
shaft for rotating the shaft in the direction of wheel rotation,
and a gearing interconnecting the shaft to the shaft means whereon
the brush means is detachably mounted.
3. The rotary toothbrush of claim 2, further comprising a bearing
plate adjacent the turbine wheel, the bearing plate being fixedly
mounted in the housing and having two diagonally opposite ports
obliquely inclined in opposite directions towards the vanes of the
turbine wheel, and the water flow control means comprising a valve
means having at least one port and means for moving the valve port
out of communication with the bearing plate ports and into
selective communication with a respective one of the bearing plate
ports for blocking the motor means and rotating the shaft means in
the reversible directions.
4. The rotary toothbrush of claim 3, wherein the water flow control
means further comprises a control rod slidably mounted in a
transverse bore in the housing, the rod having opposite ends
projecting from the housing, and transmission means interconnecting
the control rod to the valve means for moving the valve port in
response to sliding of the control rod in the bore.
5. The rotary toothbrush of claim 4, further comprising snap means
associated with the rod and the bore for resiliently retaining the
rod in a selected one of three positions.
6. The rotary toothbrush of claim 3, further comprising spring
means pressing the valve means against the bearing plate.
7. The rotary toothbrush of cliam 2, wherein the gearing comprises
a planetary gear having three planetary gear wheels rotatably
mounted in a section of the shaft means, a gearing portion on the
turbine shaft and a gearing portion on the interior wall of the
housing, the planetary gear wheels meshing with the gearing
portions whereby rotation of the turbine shaft is transmitted to
the shaft means for rotation thereof.
8. The rotary toothbrush of claim 7, wherein the turbine shaft is
axially displaceably journaled in coaxial bores in the bearing
plate and the shaft means section, the turbine shaft having an end
projecting from the shaft means section into the channel means in
the rotary shaft means, and the turbine shaft end carries a conical
valve part whereby axial displacement of the turbine shaft opens
and closes the channel means for flow of rinsing water to the brush
means and shutting off the rinsing water flow.
9. The rotary toothbrush of claim 8, further comprising means for
controlling the axial displacement of the turbine shaft, the
displacement control means including a set screw threadedly mounted
in the housing coaxially with the turbine shaft, a stop pin on the
screw, a compression spring around the stop pin and a ball held
between the compression spring and the opposite end of the turbine
shaft, the stop pin and ball being coaxial with the turbine shaft,
axial play being permitted between the ball and the opposite
turbine shaft end.
10. The rotary toothbrush of claim 8, further comprising a bushing
fixedly mounted in the housing between the shaft means section and
the turbine wheel, the bushing having an end face defining a bore
through which the turbine shaft extends, the bore having a diameter
greater than the diameter of the turbine shaft, the rotary shaft
means being axially displaceably journaled in the housing, and
axially spaced projections on the shaft means section and the
bushing end face for locking engagement upon axial movement of the
shaft means in one direction whereby rotation of the shaft means is
prevented and disengagement upon axial movement of the shaft means
in the opposite direction whereby the shaft means is free to
rotate.
11. The rotary toothbrush of claim 7, further comprising a floating
anti-friction washer mounted between the shaft means section and
the housing.
12. The rotary toothbrush of claim 1, further comprising a support
for the brush means, the shaft means having a conical end and the
support having a conforming conical recess to receive the support
on the shaft means end, and means for detachably holding the
support on the shaft means end.
13. The rotary toothbrush of claim 12, further comprising a
protective shield for the brush means, the protective shield being
detachably mounted on the housing, and a fork-shaped clamping means
connecting the shield to the support for free rotation of the
shield in respect of, and removal from, the support.
14. The rotary toothbrush of claim 1, further comprising a water
supply and removal tubing attached to the housing inlet and outlet,
the tubing including an inner tube connected to the inlet for
supplying water under pressure to the housing chamber means, the
chamber means including a first chamber adjacent the inlet, a
second chamber wherein the motor means is arranged, a port
connecting the first and second chambers, and a third chamber
wherein the rotary shaft means is arranged, the second and third
chambers being in communication, the channel means comprising a
lateral bore in the rotary shaft means in communication with the
third chamber for receiving rinsing water from the third chamber,
and the tubing including an outer tube connected to the outlet for
removal of waste water.
15. the rotary toothbrush of claim 14, wherein the means causing
the pressure reduction comprises a channel connecting the first
chamber to the water outlet.
Description
The present invention relates to improvements in a hydraulic
pressure driven rotary toothbrush.
Conventional toothbrushes, while simple and convenient, do not meet
the requirements of modern dental hygiene. Efficient dental
cleansing requires brushing to be performed in such a manner as to
prevent bacteria and food particles from being pressed into pockets
between the gum and the base of the teeth. This makes it necessary
to twist the wrist while brushing with an ordinary toothbrush. The
corresponding hand movements are complex and are difficult to
perform, particularly by children or people deprived of easy
movement of the hand and/or arm.
In an effort to obtain more effective dental cleansing, various
electrically powered toothbrushes have been designed for rotary as
well as oscillatory brushing movements. Since the electric motor
for such brushes must obviously be small to be accommodated in the
brush handle, it has a correspondingly low output efficiency.
Furthermore, it is desirable to rinse the toothbrush during
brushing to make the cleaning effective while, at the same time,
holding water consumption to a minimum for the entire operation
which should take at least about 2 minutes for a thorough brushing
to the teeth.
It is the primary object of this invention to provide an efficient
rotary toothbrush meeting the requirements of modern dental hygiene
while requiring a minimum supply of water for operating the brush
and rinsing the teeth during brushing continuously.
The above and other objects are accomplished in accordance with the
invention with a rotary toothbrush which comprises a hand held
housing and an interchangeable brush. A miniature motor, such as a
turbine operable by hydraulic pressure, is mounted in the housing
and a rotary shaft is operably associated with the motor for
rotation about the axis thereof, preferably by means of a planetary
or like reduction gearing to reduce the relatively high velocity of
the turbine to a lower rotary velocity of the shaft on which the
brush is detachably mounted. The housing defines chamber means to
which water is supplied under pressure through an inlet, flows
through the housing chamber to operate the motor and rotor the
shaft, and is drained through a water outlet. A water control
including a valve is arranged on the housing for ready manipulation
to control the water flow for blocking it from the motor, rotating
the shaft in a first direction and reversing the rotational
direction of the shaft. Channel means in the rotary shaft and the
brush is in communication with the housing chamber for receiving
rinsing water therefrom and conveying it to the brush whereby the
same water supply is used for operating the motor and delivering
rinsing water to the brush. The used water is sucked away by means
causing a pressure reduction in the housing chamber between the
motor and the water outlet to assist drainage of waste water from
the motor.
The above and other objects, advantages and features of the present
invention will become more apparent from the following detailed
description of now preferred embodiments thereof, taken in
conjunction with the accompanying drawing wherein
FIG. 1 is a perspective view of a hand-held rotary toothbrush
connected to the faucet of a wash basin;
FIG. 2 is an axial section of the toothbrush;
FIG. 3 is a transverse section along line III--III of FIG. 2,
showing a control device for reversing the rotary direction of the
brush;
FIG. 4 is a transverse section, on an enlarged scale, along line
IV--IV of FIG. 2, showing a planetary gearing for reducing the
revolutions of the rotary brush;
FIG. 5 is an axial section, on an enlarged scale, showing a detail
of the structure;
FIGS. 6 to 8 are enlarged sections illustrating different positions
of the turbine wheel;
FIG. 9 is a perspective view of an alternative embodiment of the
brush; and
FIG. 10 is a transverse section along line X--X of FIG. 9, showing
an arrangement for the detachable connection of the brush and
protective shield.
Referring now to the drawing and first to FIG. 1, there is shown a
rotary toothbrush 1 powered by water pressure, a flexible tube 2
having one end connected to faucet 3 on wash basin 4 by means of
connector 5 while the other tube end is connected to the
toothbrush. As shown in the drawing, the toothbrush has a section
shaped to be gripped firmly by hand 6 of a user so that the user
may comfortably perform all brush movements. For the sake of
clarity, toothbrush 1 has been shown on a larger scale than the
wash basin and other attachments.
The longitudinal section of FIG. 2 illustrates the toothbrush
structure. As shown, the toothbrush comprises hand gripping section
7 and brush means 8 partially surrounded by protective shield 9.
The hand gripping section of the toothbrush consists essentially of
housing part 12 and cover part 3 which together define and enclose
a chamber housing the rotary drive mechanism and necessary water
passages. The power drive is provided by turbine wheel 14 keyed to
turbine shaft 16. The turbine shaft is journaled in bearing plate
17 and has an end 19 projecting into axial bore 28 at the inner end
of rotary shaft 18 carrying the brush. The bearing plate is
carefully machined to fit into the chamber defined by housing 12
and has skirts 19 and 21 to enable the bearing plate to be retained
in the housing chamber by placing cover 13 over the open housing
end and securing it thereto by tightening screws 20. As will be
seen in FIG. 2, the rim of cover 13 presses against skirt 19 of the
bearing plate and opposite bearing plate skirt 21 simultaneously
presses against a flange of bushing 22, thus holding the bushing
flange against a shoulder in the housing chamber and retaining the
bushing firmly therein.
Hand gripping section 7 has a cylindrical portion projecting
therefrom and housing planetary gearing 15 shown best in FIG. 4.
The planetary gearing comprises three planetary wheels 23, 24, 25
equidistantly spaced about turbine shaft 16 and meshing with
gearing portion 30 on the shaft as well as with gearing portion 31
on the inner surface of the cylindrical portion of the hand
gripping section.
Rotary shaft 18 has an enlarged end section 27 forming a squirrel's
cage with three openings 32 housing the planetary wheels, shaft end
section 27 being housed in the cylindrical portion of hand gripping
section 7 and carrying axles 26 whereon the planetary wheels are
mounted.
Cylindrical portion 33 of rotary shaft 18 projects from its end
section 27 and is journaled in axial bore 34 of the cylindrical
portion of hand gripping section 7. O-ring 35 or an equivalent
sealing means is arranged in an annular groove in bore 34. The end
of cylindrical shaft portion 33 projecting beyond housing 12
carries a preferably coarse thread 36, followed by conical part 37.
The thread on the cylindrical shaft portion may be replaced by a
bayonet or similar joint for attaching the brush to the shaft.
Axial bore 38 passes from bore 28 through shaft 18 for conveying
rinsing water to brush means 8.
The brush means comprises a brush part 39 mounted on support 40
formed with conical axial recess 42 confirming to conical part 37
and thread 41 to mesh with thread 36 for attachment of the brush
means to rotary shaft 18. Support 40 has axial bore 43 aligned with
bore 38 and in communication with discharge ports 44 for passing
rinsing water to the brush part. As shown, support 40 is knurled at
47 to enable it to be gripped firmly for threadedly connecting the
support to the shaft. When the brush means is mounted on the rotary
shaft, support 40 must be screwed so tightly on shaft 18 that the
conical surfaces 37 and 42 form a tight seal. Therefore, shaft 18
must be held against rotation when brush means 8 is emplaced or
removed. For this purpose, the following locking arrangement is
provided for rotary shaft 18:
The outer, ring-shaped part of rotary shaft end section 27 carries
sector-shaped projections 45 facing corresponding projections 46 on
the end face of bushing 22. When shaft 16 is in its freely
rotatable position, as shown in FIG. 2, there is an axial gap
S.sub.1 between projections 45 and 46. The shaft is mounted in
housing 12 for axial displacement by a distance S.sub.2 exceeding
the length of gap S.sub.1. Simple manual pressure on support 40
will slide shaft 18 down in the direction of hand gripping section
7 until projections 45 and 46 engage and thus prevent the shaft
from turning about its axis. Thus held against rotation, the shaft
can now be joined tightly with support 40 of brush means 8 or the
support may be removed therefrom. In use, shaft 18 will be axially
moved upwardly again into the position shown in FIG. 2.
The turbine wheel structure and operation is best shown in FIGS. 6
to 8. Turbine wheel 14 has vanes 48 shaped to be operated by jets
of water for rotation clockwise or counterclockwise. Valve 49
cooperates with the turbine wheel, three different operating
positions being shown in FIGS. 6 to 8.
Adjustable valve 49 is mounted for turning in bushing 22 fixedly
held in housing 12 in a manner previously described. As best shown
in FIG. 3, the valve may be adjusted into different positions by
control rod 50 which is mounted for sliding movement in housing 12,
the axis of slidable rod 50 extending transversely to the axis of
rotary shaft 16 and rod 50 being reciprocable in the direction of
double-headed arrow P.sub.1. The valve has a cylindrical portion 52
journaled in bushing 52 and the cylindrical valve portion has a
gear segment 53 meshing with rack 51 forming the central portion of
control rod 50. When the control rod is manually moved, by simple
thumb pressure on rod ends 54, 55, for instance, in the direction
of arrow P.sub.1, the valve will be turned in relation to bearing
plate 17 fixedly retained in housing 12. Two O-rings 55, 56 near
respective rods ends 54, 55 are mounted in circumferential grooves
in rod 50. These O-rings serve the double function of providing a
seal between the rod and housing 12 and also tend because of their
inherent resilency to retain the rod in each adjusted axial
position, as will be described in detail hereinafter. The three
positions of the control rod are determined by the positions of
three annular grooves 57, 58, 59 in housing 12 in the path of the
axial movement of control rod 50. As the rod is axially moved, the
O-rings will enter a respective one of the annular grooves, as
illustrated by groove 58 in FIG. 3, thus being resiliently retained
in the respective position without being locked thereinto against
further axial movement by a relatively light pressure of the
thumb.
The three mentioned positions of rod 50 correspond to the three
positions of valve 49 shown in FIGS. 6 to 8. The valve has at least
one port 60 for alignment with oblique port 61 or 62 in bearing
plate 17. In the first position shown in FIG. 6, valve port 60 is
in communication with bearing plate port 61 to permit water under
pressure to flow in the direction of arrow P.sub.2 against vanes 48
of turbine wheel 14. This will bring about a clockwise rotation of
the wheel and rotary shaft 16 in the direction of arrow
P.sub.3.
In the centered position shown in FIG. 7, valve port 60 is out of
communication with any bearing plate port and the turbine wheel
will stand still. In the position shown in FIG. 8, valve port 60 is
in communication with bearing plate port 62 to permit water under
pressure to flow in the direction of arrow P.sub.4 to turn the
turbine wheel and rotary shaft 16 in the counterclockwise direction
indicated by arrow P.sub.5. Thus, rotation of shaft 16 may be
reversed or stopped by axial movement of control rod 50.
Valve 49 is biased against bearing plate 17 be means of spring
washer 63 mounted between the end face of bushing 22 and the
cylindrical portion 52 of the valve.
In order to control the amount of rinsing water passing through
axial bores 38, 43, shaft end 29 carries conical valve port 64
forming a needle valve with the inner end of bore 38 whereinto it
projects, the bore end constituting a valve seat for valve part 64.
As shown in FIG. 5, water under pressure is forced into annular
space 65 surrounding valve part 64 through lateral bore 66 in shaft
end section 27 in the direction of arrow P.sub.6.
Rotary shaft 16 is axially displaceably mounted on cover 13,
conical valve port 64 being biased into closing bore 38 by
compression spring 67 which is mounted on stop pin 71 in axial bore
69 of set screw 70. The set screw is threaded into cover 13
coaxially with shaft 16 and ball 68 is interposed between end 72 of
pin 71 and the end of shaft 16. The stop pin has a length selected
to permit a little axial play S.sub.3 between ball 68 and pin end
72 when the set screw has been threaded into cover 13 sufficiently
to enable spring 67 to press shaft 16 upwardly for moving valve
part 64 into closing engagement with bore 38. When water under
pressure flows through valve 49 in the direction of arrow P.sub.2
or P.sub.4 (FIGS. 6 and 8), it will press turbine wheel 14
downwardly against the bias of spring 67, the wheel being keyed to
shaft 16 for movement therewith, and thus level out axial play
S.sub.3, thus moving valve part 64 out of engagement with bore 38
and opening the same to receive a flow of rinsing water through
bore 66. Adjustment of set screw 70 enables the amount of rinsing
water passing through bore 38 to be regulated.
Hydraulic pressure for turning turbine wheel 14 and shaft 16 is
supplied from wash basin faucet 3 by tubing 2 which consists of
flexible inlet tube 11 surrounded by flexible outlet tube 10. One
end of the tubing is detachably mounted on connector 5 and the
other tubing end is detachably mounted on nipple 73 which is
integral with housing 12 and comprises inlet 74 whereon inner tube
11 is mounted to receive water under pressure flowing in the
direction of arrow P.sub.8. The nipple inlet widens into chamber 75
defined by a thickened portion of the wall of housing 12, which
forms the nipple. Chamber 75 is in communication with annular
chamber 77 through lateral port 76, valve 49 being housed in
chamber 77 so that water under pressure may flow through inlet 74,
chamber 75, port 76, chamber 77 and valve port 60 for turning
turbine wheel 14. Annular chamber 77 is in communication with
annular chamber 78 surrounding the cylindrical portion of valve 49
and an axial bore in the end face of bushing 12 of a diameter
larger than that of shaft 16 places chamber 78 in communication
with annular chamber 79 surrounding end section 27 of shaft 18,
thus permitting water to flow through lateral bore 66 in the
direction of arrow P.sub.6 (see FIG. 5), as previously
described.
Except for turbine shaft 16, planetary wheel axles 26, spring 67
and ball 68, spring 63, and possibly the O-rings, brush part 39 and
tubing 2, all parts of the toothbrush are preferably made of a
molded synthetic resin. For this reason and due to practical
production requirements, ports will be formed in the thickened
portion of the wall of housing 12 adjacent chamber 75, and these
ports are sealed with plugs 80, 80a.
Cover 13 and bearing plate 17 define chamber 82 below and around
turbine wheel 14 to receive the water flowing through valve 49 and
operating the turbine wheel, chamber 82 being in communication with
chamber 75 through channel 81 boxed in thickened wall portion of
housing 12. Channel 81 leads to the outlet of nipple 73 to which
outer tube 10 is attached.
Protective shield 9 for brush part 39 has a ring-shaped connector
part 83 for frictional engagement with cylindrical upper section 84
of housing 12 so that the shield may be detachably mounted on the
toothbrush. This mounting will be facilitated if part 83 is
somewhat elastic so as to be held firmly on housing section 84. A
snap fit would also be possible.
In the modified embodiment of FIG. 9, the brush part is not an
elongated cylindrical member, as shown in FIG. 2, but consists of
spiral brush 39' enhancing the cleansing effect of the brush upon
rotation. Furthermore, brush protective shield 9' carries
fork-shaped retainer 85 (see FIG. 10) gripping annular groove 86 of
brush support 40'. This makes it possible to turn the shield in
respect of the brush part. In either embodiment, it will be simple
to remove the shield and the brush means for ready replacement by
another shield and brush means so that different persons may use
the device.
The operation of the rotary toothbrush hereinabove described will
partly be evident from the described structure and will be further
detailed hereinbelow.
In use, one end of tubing 2 with connector 5 is so mounted on
faucet 3 that inner tube 11 is in communication with the faucet,
which may be turned on to permit water to flow through tube 11
under pressure, while outer tube 10 if open at that end to drain
water from the operating toothbrush in the direction of arrow
P.sub.7 (See FIG. 1). The faucet is set for a moderate flow of
water which, as shown by arrow P.sub.8 in FIG. 2, enters through
inlet 73 and fills all the chambers in the toothbrush housing, as
indicated by the arrows in FIG. 2 which show the direction of water
flow, some of the water under pressure simultaneously flowing over
through channel 81 to depressurize chamber 82. If valve 49 is in
its center position (see FIG. 7), turbine wheel 14 will stand
still, i.e., no rotary driving power is transmitted to the brush
shaft and no water enters chamber 82 through the valve. However,
the water pressure will axially move brush shaft 18 the distance
S.sub.2 so that it will be unlocked if it had previously been
locked for replacement of the brush means, as described
hereinabove.
Upon manipulation of control rod 50, valve 49 will be moved into an
operating position, as indicated in FIGS. 6 or 8, so that hydraulic
pressure will begin to turn the turbine wheel, the operating water
flowing out through chamber 82 and being sucked into tube 10 by the
water passing through channel 81. If desired, the direction of
rotation may be reversed during operation by manipulation of
control rod 50 in the previously described manner.
The rotary direction of the brush may be rapidly changed for every
group of teeth being brushed so that brushing is effected in a
direction from the gum upward towards the teeth so that food
particles are not pressed down between the base of the teeth and
the gums. During brushing, protective shield 9 prevents brush part
39 from coming into contact with parts of the mouth which should
not be touched by the brush.
The amount of rinsing water passing through discharge ports 44 to
brush part 39 is set by screw 70 in the manner previously described
to any desired amount. Thus, the teeth are effectively brushed and
simultaneously rinsed, the rotary control during operation being
exceedingly simple by pressure manipulation of rod 50.
Most parts of the toothbrush being of molded plastic, mass
production at low cost is available, a preferred synthetic resin
for the manufacture of these molded parts being Teflon.
As shown in FIG. 2, it will be useful to place a floating
anti-friction washer 87, for instance of Teflon or another suitable
material of low friction coefficient, between section 27 of shaft
18 and cylindrical portion 84 of housing 12 so as to seal off the
housing chambers filled with water during operation.
A useful material for the manufacture of turbine shaft 16,
planetary wheels 23-25 and their axles 26, ball 68 and springs 67
and 63 is stainless steel.
Since all the moving parts are automatically lubricated by the
flowing water, they will be subject to slight wear only and have a
long operating life. Also, water consumption during operation is
low since the amount of rinsing water supplied to the brush
obviously must be relatively limited and the amounts of water
producing the turbine wheel operating jets through bores 61, 62 are
also quite limited.
While the rotary toothbrush has been described herein in connection
with certain preferred embodiments thereof, it will be clearly
understood that various modifications may occur to those skilled in
the art, particularly after benefitting from the present teaching,
without departing from the spirit and scope of this invention as
defined in the appended claims.
* * * * *