BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to a washing machine, and
more particularly to a washing machine provided with an
improved nozzle for spraying washing water into a drum at a
broadened angle.
Description of the Related Art
Generally, washing machines are apparatuses for removing
contaminants from laundry by the action of detergent and water.
Such washing machines are divided into agitator-type
washing machines, pulsator-type washing machines, and drum-type
washing machines.
The agitator-type washing machine washes laundry placed
therein by rotating a rod rising from a central area of a
washing tank in both directions. The pulsator-type washing
machine washes laundry placed therein by means of friction
between the laundry and a water current generated by rotating a
pulsator having a disk shape installed on a lower portion of a
washing tank in both directions. The drum-type washing machine
washes laundry placed in a drum by rotating the drum including
a plurality of lifters protruded from an inner surface thereof
and containing water, detergent and the laundry.
The above-described conventional washing machines, such
as the agitator-type washing machines, the pulsator-type
washing machines, and the drum-type washing machines, are
provided with various subsidiary devices for increasing washing
efficiency. For example, a washing water-circulating device is
installed in the washing machines.
The washing water-circulating device causes water
containing detergent or pure and clean water without detergent
(hereinafter, referred to as "washing water") to soak into the
laundry placed in the drum, thus reducing a quantity of the
washing water. Further, the washing water-circulating device
increases friction between the laundry and a current of the
washing water, thus increasing washing capacity. Accordingly,
the washing water-circulating device serves to pump the washing
water placed in the lower portion of a tub and to spray the
pumped washing water into the drum.
The washing water-circulating device includes a nozzle
for spraying circulating washing water into the drum. The
circulating washing water sprayed from the nozzle is required
to be directed to the inside of the drum at a broadened angle.
SUMMARY OF THE INVENTION
Therefore, the present invention has been made in view
of the above problems, and it is an object of the present
invention to provide a washing machine provided with a nozzle
for spraying washing water into a drum at a broadened angle,
thus improving washing efficiency and rinsing efficiency, and
reducing a quantity of the washing water consumed.
In accordance with one aspect of the present invention,
the above and other objects can be accomplished by the
provision of a washing machine comprising a tub for containing
washing water, a drum rotatably arranged in the tub for
accommodating laundry, a motor for rotating the drum, and a
washing water-circulating device for circulating the washing
water so that the washing water in the tub is sprayed into the
drum, wherein the washing water-circulating device includes a
nozzle having a vertical water-spraying angle in the range of
30° to 40°.
In accordance with a further aspect of the present
invention, there is provided a washing machine comprising a
tub for containing washing water, a drum rotatably arranged in
the tub for accommodating laundry, a motor for rotating the
drum, and a washing water-circulating device for circulating
the washing water so that the washing water in the tub is
sprayed into the drum, wherein the washing water-circulating
device includes a nozzle having a horizontal water-spraying
angle in the range of 110° to 130°.
In accordance with another aspect of the present
invention, there is provided a washing machine comprising a
tub for containing washing water, a drum rotatably arranged in
the tub for accommodating laundry, a motor for rotating the
drum, and a washing water-circulating device for circulating
the washing water so that the washing water in the tub is
sprayed into the drum, wherein the washing water-circulating
device includes a nozzle having different right and left
vertical water-spraying angles.
In accordance with yet another aspect of the present
invention, there is provided a washing machine comprising a
tub for containing washing water, a drum rotatably arranged in
the tub for accommodating laundry, a motor for rotating the
drum, and a washing water-circulating device for circulating
the washing water so that the washing water in the tub is
sprayed into the drum, wherein the washing water-circulating
device includes a nozzle having different right and left
horizontal water-spraying angles.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects, features and other
advantages of the present invention will be more clearly
understood from the following detailed description taken in
conjunction with the accompanying drawings, in which:
Fig. 1 is a partially exploded perspective view of an
embodiment of a washing machine in accordance with the present
invention; Fig. 2 is a longitudinal-sectional view of the
embodiment of the washing machine in accordance with the
present invention; Fig. 3 is a longitudinal-sectional view of a first
embodiment of a nozzle of the washing machine in accordance
with the present invention; Fig. 4 is a partially exploded sectional view of the
first embodiment of the nozzle, through which washing water is
sprayed into a drum, in accordance with the present invention; Fig. 5 is a cross-sectional view of a second embodiment
of the nozzle of the washing machine in accordance with the
present invention; Fig. 6 is a rear view of a third embodiment of the
nozzle of the washing machine in accordance with the present
invention; Fig. 7 is a partially exploded sectional view of the
third embodiment of the nozzle, through which washing water is
sprayed into the drum, in accordance with the present
invention; and Fig. 8 is a cross-sectional view of a fourth embodiment
of the nozzle of the washing machine in accordance with the
present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Now, preferred embodiments of the present invention will
be described in detail with reference to the annexed drawings.
In the drawings, the same or similar elements are denoted by
the same reference numerals even though they are depicted in
different drawings. In the following description of the present
invention, a detailed description of known functions and
configurations incorporated herein will be omitted when it may
make the subject matter of the present invention rather
unclear.
Fig. 1 is a partially exploded perspective view of an
embodiment of a washing machine in accordance with the present
invention. Fig. 2 is a longitudinal-sectional view of the
embodiment of the washing machine in accordance with the
present invention.
As shown in Figs. 1 and 2, the washing machine of the
present invention comprises a casing 2, a tub 10 located in
the casing 2 so that the tub 10 is stably supported by the
casing 2 for containing washing water (w), a drum 20 rotatably
arranged in the tub 10 for accommodating laundry (m), and a
driving motor 30 for rotating the drum 20.
The casing 2 includes a base 3 provided with a damper 3a
connected to the tub 10, a cabinet 4 located on the base 3 for
surrounding both side surfaces and a rear surface of the tub
10 and provided with a spring 4a connected thereto for
suspending the tub 10 therewith, a cabinet cover 5 arranged in
front of the cabinet 4 for covering a front surface of the
cabinet 4 and provided with an entrance hole 5a formed at a
central area thereof for placing the laundry (m) into the tub
10 therethrough, a top plate 6 for covering an upper surface
of the cabinet 4, and a control panel 7 installed on an upper
surface of the cabinet cover 5 or the top plate 6 for
controlling the washing machine.
A door 9 for opening and closing the entrance hole 5a is
installed on the cabinet cover 5.
The door 9 includes a door frame 9c provided with an
opening at a central area thereof and a locking unit 9b locked
with the cabinet cover 5 and provided with one side connected
to the cabinet cover 5 by a hinge 9a, and a door glass 9d
installed at the opening of the door frame 9c and formed in a
convex surface directed to the drum 20.
The tub 10 includes an opening 12 for allowing the
laundry (m) to be put into the drum 20 therethrough, and a
gasket 14 provided with a sealing portion, contacting a rear
surface of the door frame 9c or the door glass 9d, around the
opening 12, thereby preventing the washing water (w) from
leaking from the tub 10 and the laundry (m) from being
separated from the tub 10.
The drum 20 includes an entrance hole 21 formed through
a front surface thereof for placing the laundry (m) into the
drum 20 therethrough, a plurality of through holes 22 formed
through a side surface and a rear surface thereof for allowing
the washing water (w) to pass through the drum 20
therethrough, and lifters 23 formed on an inner circumference
thereof for lifting and dropping the laundry (m). A lower
portion of the drum 20 is submerged in the washing water (w)
in the tub 10.
The driving motor 30 is installed on the rear surface of
the tub 10. A rotary shaft 31 of the driving motor 30, which
penetrates the rear surface of the tub 10, is supported by the
tub 10 and connected to the rear surface of the drum 20.
A water supply unit is provided on the tub 10 for
supplying the washing water (w) into the tub 10.
The water supply unit includes a water supply valve 41
connected to an external hose 40 for intermittently
controlling clean water (w) supplied from the external hose
40, a water supply hose 42 for guiding the water passed
through the water supply valve 41, a detergent box 43
including a detergent storing space, a water supply passage
and an outlet for causing the water supplied from the water
supply hose 42 to be mixed with detergent stored by the
detergent storing space and then to be discharged therefrom,
and a water supply bellows tube 44 having one end connected to
the outlet of the detergent box 43 and the other end connected
to an inlet formed at a designated position of the upper
surface of the tub 10 for guiding the water or detergent
discharged from the detergent box 43 into the tub 10.
A drainage hole 15 is formed through the lower surface
of the tub 10 for discharging the washing water (w) to the
outside therethrough, and is connected to a drainage bellows
tube 48 for guiding the washing water (w) discharged from the
tub 10.
A pump unit 50, for pumping out or re-circulating into
the drum 20 the washing water (w) discharged from the tub 10
through the drainage hole 15 and the drainage bellows tube 48,
is connected to the drainage bellows tube 48.
The pump unit 50 includes a filter case 52, a drainage
pump 54, and a circulating pump 56.
The filter case 52 includes a connector connected to the
drainage bellows tube 48, a passage, for passing the washing
water (w) therethrough, connected to the drainage pump 54 and
the circulating pump 56, and a filter for filtering foreign
substances, such as waste pieces of thread, from the washing
water (w).
A drainage hose 55 extended toward the outside of the
casing 2 is connected to the drainage pump 54, and serves to
discharge the washing water (w) introduced into the pump case
52 to the outside in a drain mode of the washing machine.
A circulating hose 60 extended toward the upper end of
the gasket 14 is connected to the circulating pump 56, and
serves to pump out the washing water (w) introduced into the
filter case 52 in a wash or rinse mode of the washing machine.
One end of the circulating hose 60 is adjacent to the
upper end of the gasket 14.
A spraying unit provided with a nozzle for spraying the
guided washing water (w) into the drum 20 is connected to the
circulating hose 60.
Fig. 3 is an enlarged longitudinal-sectional view of a
first embodiment of a nozzle of the washing machine in
accordance with the present invention. Fig. 4 is a partially
exploded sectional view of the first embodiment of the nozzle,
through which washing water is sprayed into a drum, in
accordance with the present invention.
As shown in Figs. 3 and 4, the gasket 14 includes a
cylindrical rib 14b, and a through hole 14a formed through the
cylindrical rib 14b.
The spraying unit serves to spray the washing water
pumped through the circulating hose 60 from the inside of the
gasket 14 to the inside of the drum 20, and includes a
cylinder 72 protruded from the upper end of the cylindrical
rib 14b, connected to the circulating hose 60 and provided
with a through hole 72a, located in the through hole 14a and
the cylindrical rib 14b for passing the washing water (w)
therethrough, and a nozzle 74 provided on a lower end of the
cylinder 72 for spraying the washing water passed through the
cylinder 72 into the drum 20 at a broadened angle.
A protrusion 72b, formed in a hook structure, is formed
on an outer circumference of the cylinder 72 and caught by an
upper portion of the cylindrical rib 14b, thereby preventing
the cylinder 72 from coming out from the lower end of the
gasket 14 due to a dead weight of the cylinder 72, a water flow
and external vibration.
The cylinder 72 is pushed into the gasket 14 through the
through hole 14a.
The nozzle 74 is formed integrally with the lower end of
the cylinder 72, and located on the upper portion of the inside
of the gasket 14.
The nozzle 74 has a vertical spraying angle (α) in the
range of 30° to 40° so that the washing water (w) sprayed from
the nozzle 74 is directed to the lower portion of the rear
surface 26 or the circumferential portion 28 of the drum 20.
In case that the vertical spraying angle (α) of the
nozzle 74 is excessively small, the sprayed washing water (w)
is directed only to the upper portion of the rear surface 26 of
the drum 20. In case that the vertical spraying angle (α) of
the nozzle 74 is excessively large, the sprayed washing water
(w) is directed only to the front part of the circumferential
portion 28 of the drum 20. Accordingly, the vertical spraying
angle (α) of the nozzle 74 is limited to 30° to 40° so that the
sprayed washing water (w) is uniformly directed into the drum
20.
A rear surface of the nozzle 74 facing the rear surface
26 of the drum 20 is opened, and both side surfaces of the
nozzle 74 are partially opened. The nozzle 74 includes an upper
horizontal portion 75 protruded horizontally from the lower end
of the cylinder 72, a front vertical portion 76 protruded
perpendicularly from the upper horizontal portion 75, and a
lower sloping portion 77 extended from a lower end of the front
vertical portion 76 and located below the through hole 72a.
The front vertical portion 76 is bent from a front end of
the upper horizontal portion 75.
In case that the lower sloping portion 77 has an
excessively small nozzle height (H), which is a distance from
the lower end of the through hole 72a to the lower sloping
portion 77, it is difficult to efficiently spray the washing
water (w). In case that the lower sloping portion 77 has an
excessively large nozzle height (H), the lower sloping portion
77 interferes with the door glass 9d and a spraying length of
the washing water (w) directed to the inside of the drum 20 is
reduced. Accordingly, preferably, the lower sloping portion 77
has a nozzle height (H) in the range of 2mm to 4mm.
Preferably, the lower sloping portion 77 has a length (L)
limited to the range of 20mm to 25mm so as to sufficiently guide
the washing water (w) and prevent the interference with the
door glass 9d located around the lower sloping portion 77.
When the through hole 72a of the cylinder 72 has a
reduced diameter (d), the water spraying length of the lower
sloping portion 77 is increased and a passage loss is
increased. Accordingly, in case that the vertical spraying
angle (α) of the nozzle 74 is in the range of 30° to 40°, it is
preferable that the diameter (d) of the through hole 72a of the
cylinder 70 is 0.4 to 0.65 times as large as the diameter (D)
of the nozzle 74.
Hereinafter, operation of the washing machine of the
present invention will be described in detail.
First, the laundry (m) is put into drum 20, and the door
9 is closed into the cabinet cover 5. Thereafter, the washing
machine is operated. Then, the lower portion of the tub 10, the
drainage bellows tube 48 and the filter case 52 are filled with
the washing water (w) supplied from the water supply bellows
tube 44, and the laundry (m) in the drum 20 is submerged in the
washing water (w) introduced thereinto through the through
holes 22.
Thereafter, the driving motor 30 is operated so as to
rotate the drum 20, and the laundry (m) in the drum 20 is
lifted and then dropped by the lifters 23, thereby being
cleaned by the action of the detergent and the water.
In a water supply or wash mode of the washing machine,
the circulating pump 56 is operated so as to pump out the
washing water (w) within the filter case 52. The washing water
(w) pumped by the circulating pump 56 is guided to the upper
portion of the gasket 14 through the circulating hose 60,
passes through the through hole 72a of the cylinder 72, and is
then dropped.
The washing water (w) dropped through the through hole
72a of the cylinder 72 collides with the upper surface of the
lower sloping portion 77, and is then sprayed onto the lower
portion of the rear surface 26 or the circumferential portion
28 of the drum 20, thereby uniformly soaking the laundry (m).
Generally, the laundry (m) is lifted up to the upper
portion of the inside of the drum 20, and is then dropped.
However, a part of the laundry (m) is lifted up to a middle
portion of the inside of the drum 20 and is then dropped, and
the washing water (w) sprayed by the nozzle 72 is directed
broadly to the lower portion of the rear surface 26 or the
circumferential portion 28 of the drum 20. Therefore, the
washing water (w) directly soaks the part of the laundry (m),
which is lifted up to the middle portion of the inside of the
drum 20 and is then dropped.
That is, since the washing water (w), which circulates,
uniformly soaks all of the laundry (m), the washing machine of
the present invention reduces a quantity of the supplied
washing water (w) at the same washing capacity and improves
washing efficiency at the same quantity of the washing water
(w) consumed.
After the wash mode of the washing machine is finished,
contaminated water remains in the lower portion of the tub 10,
the drainage bellows tube 48 and the filter case 52. Such
contaminated water is discharged to the outside through the
drainage hose 55 when the drainage pump 54 is operated.
Further, the washing machine is operated in a rinse mode,
in which clean washing water (w) is supplied into the tub 10 so
as to rinse soap bubbles out of the laundry (m). In case that
the rinse mode of the washing machine is selected, the washing
water (w) supplied from the water supply bellows tube 44 is
contained in the lower portion of the tub 10, the drainage
bellows tube 48 and the filter case 52, the motor 30 is driven
so as to rotate the drum 20 for rinsing the laundry (w), and
the laundry (m) in the drum 20 is lifted by the lifters 23 and
is then dropped. Thereby, soap bubbles are rinsed out of the
laundry (m) by the washing water (w).
During the water supply or rinse mode of the washing
machine, the circulating pump 56 is operated in the same manner
as in the wash mode of the washing machine, and the washing
water (w) passed through the nozzle 74 is broadly sprayed onto
the lower portion of the rear surface 26 or the circumferential
portion 28 of the drum 20 at a vertical spraying angle (α) of
the lower sloping portion 77 in the range of 30° to 40°, thus
uniformly soaking the laundry (m). Accordingly, the washing
machine of the present invention reduces a quantity of the
supplied washing water (w) at the same rinsing capacity and
improves rinsing efficiency at the same quantity of the washing
water (w).
Since the rinsing efficiency is directly proportional to
the quantity of the washing water and the square of the number
of times of rinse mode, it is preferable to repeat the rinse
mode several times using a small quantity of the washing water
(w) in order to obtain the same rinsing capacity. Since the
washing water (w) sprayed by the nozzle 74 uniformly contacts
the laundry (m), the number of times, that the rinse mode is
performed, is increased in order to reduce the quantity of the
washing water (w) while maintaining the rinsing capacity.
After the rinse mode of the washing machine is finished,
contaminated water remains in the lower portion of the tub 10,
the drainage bellows tube 48 and the filter case 52. Such
contaminated water is discharged to the outside through the
drainage hose 55 when the drainage pump 54 is operated.
Thereafter, in case that a dehydration mode of the
washing machine is selected, the drum 20 is rotated at a high
speed so that the laundry (m) is centrifugally dehydrated.
Fig. 5 is a cross-sectional view of a second embodiment
of the nozzle of the washing machine in accordance with the
present invention.
As shown in Fig. 5, the nozzle 74 of this embodiment has
a horizontal spraying angle in the range of 110° to 130° so
that the sprayed washing water is not spread over sides of the
nozzle 74 and is directed concentrically to the inside of the
drum 20. Other elements, such as the circulating device, in
the second embodiment except for the nozzle 74 are
substantially the same as those in the first embodiment and
thus denoted by the same reference numerals even though they
are depicted in different drawings. Thus, a detailed
description of such elements in the second embodiment will be
omitted because it is considered to be unnecessary.
The washing water (w) sprayed by the nozzle 74 tends to
gradually get bent inwardly. Preferably, the nozzle 74 has an
opened rear surface and an angle between both side surfaces of
the nozzle 74 in the range of 130° to 140° in order to obtain
the horizontal spraying angle of the nozzle 74 in the range of
110° to 130°.
The nozzle 74 includes the upper horizontal portion
protruded horizontally from the lower end of the cylinder, the
front vertical portion 76 protruded perpendicularly from the
upper horizontal portion, the lower sloping portion 77 extended
from the lower end of the front vertical portion 76, and side
vertical portions 78 and 79 located between both sides of the
upper horizontal portion and the lower sloping portion 77 at a
horizontal sloping angle in the range of 130° to 140°. The
washing water (w) colliding with the upper surface of the lower
sloping portion 77 is collected by the side vertical portions
78 and 79, and concentrically sprayed into the drum 20.
Fig. 6 is a rear view of a third embodiment of the
nozzle of the washing machine in accordance with the present
invention. Fig. 7 is a partially exploded sectional view of
the third embodiment of the nozzle, through which washing
water is sprayed into the drum, in accordance with the present
invention.
As shown in Figs. 6 and 7, the nozzle 74 of this
embodiment has left and right vertical spraying angles having
different degrees. Other elements, such as the circulating
device, in the third embodiment except for the nozzle 74 are
substantially the same as those in the first or second
embodiment and thus denoted by the same reference numerals
even though they are depicted in different drawings. Thus, a
detailed description of such elements in the third embodiment
will be omitted because it is considered to be unnecessary.
The nozzle 74 includes the upper horizontal portion 75
protruded horizontally from the lower end of the cylinder 72,
the front vertical portion 76 protruded perpendicularly from
the upper horizontal portion 75, and the lower sloping portion
77 extended from the lower end of the front vertical portion 76
and located to be opposite to the through hole of the cylinder
72. Here, one side of the lower sloping portion 77 has a
vertical spraying angle in the range of 5° to 20°, and the
other side of the lower sloping portion 77 has a vertical
spraying angle in the range of 30° to 50°.
The washing water collides with the upper surface of the
lower sloping portion 77 of the nozzle 74, and is then sprayed
from both sides of the lower sloping portion 77 at different
vertical spraying angles.
That is, a part of the washing water guided to one
portion 77a, having a larger vertical spraying angle, of the
nozzle 74 is sprayed onto the circumferential portion 28 of the
drum 20, and the other part of the washing water guided to the
other portion 77b, having a smaller vertical spraying angle, of
the nozzle 74 is sprayed onto the rear surface 26 of the drum
20.
Further, it is possible to linearly reduce the vertical
spraying angles of the portions 77a and 77b, to reduce the
vertical spraying angles of the portions 77a and 77b step by
step, or to irregularly arrange the portions 77a and 77b in a
horizontal direction.
Fig. 8 is a cross-sectional view of a fourth embodiment
of the nozzle of the washing machine in accordance with the
present invention.
As shown in Fig. 8, the nozzle 74 of this embodiment has
horizontal spraying angles (γ1, γ2) of different degrees.
Other elements, such as the circulating device, in the fourth
embodiment except for the nozzle 74 are substantially the same
as those in the first, second or third embodiment and thus
denoted by the same reference numerals even though they are
depicted in different drawings. Thus, a detailed description
of such elements in the fourth embodiment will be omitted
because it is considered to be unnecessary.
The nozzle 74 includes the upper horizontal portion
protruded horizontally from the lower end of the cylinder, the
front vertical portion 76 protruded perpendicularly from the
upper horizontal portion, the lower sloping portion 77 extended
from the lower end of the front vertical portion 76 and located
to be opposite to the through hole of the cylinder, and the
side vertical portions 78 and 79, located between both sides of
the upper horizontal portion and the lower sloping portion 77,
having difference horizontal sloping angles. Here, one side of
the lower sloping portion 77 has a horizontal spraying angle in
the range of 30° to 50°, and the other side of the lower
sloping portion 77 has a horizontal spraying angle in the range
of 60° to 80°.
That is, the nozzle 74 has an opened rear surface, and
one side vertical portion 78 of the side vertical portions 78
and 79 has a comparatively small horizontal spraying angle
(γ1), thereby allowing washing water, which collides with the
lower sloping portion 77 and is guided along the side vertical
portion 78, to be directed to the rear surface of the drum.
Further, the other side vertical portion 79 of the side
vertical portions 78 and 79 has a comparatively large
horizontal spraying angle (γ2), thereby allowing washing
water, which collides with the lower sloping portion 77 and is
guided along the side vertical portion 79, to be directed to
the circumferential portion of the drum.
As apparent from the above description, the washing
machine of the present invention has advantages as follows.
First, the washing machine comprises a nozzle having a
vertical spraying angle in the range of 30° to 40° so that
washing water sprayed from the nozzle is directed to a lower
portion of a rear surface or a circumferential portion of a
drum and uniformly directed to laundry in the drum, thereby
improving washing and rinsing efficiency and reducing a
quantity of the washing water consumed.
Second, a washing machine comprises a nozzle having a
horizontal spraying angle in the range of 110° to 130° so that
washing water sprayed from the nozzle is concentrically
directed to the drum in order to minimize washing water leakage
through a gap between the drum and the tub, thereby improving
washing and rinsing efficiency and reducing a quantity of the
washing water consumed.
Third, a washing machine comprises a nozzle having
different left and right vertical spraying angles so that a
part of washing water guided to a portion of the nozzle having
a comparatively small vertical spraying angle is directed to a
rear surface of a drum and the part of washing water guided to
a portion of the nozzle having a comparatively large vertical
spraying angle is directed to a circumferential portion of the
drum, thus allowing the washing water to be uniformly directed
to laundry in the drum, thereby improving washing and rinsing
efficiency and reducing a quantity of the washing water
consumed.
Fourth, a washing machine comprises a nozzle having
different left and right horizontal spraying angles so that a
part of washing water guided to a portion of the nozzle having
a comparatively small horizontal spraying angle is directed to
a rear surface of a drum and the part of washing water guided
to a portion having a comparatively large horizontal spraying
angle is directed to a circumferential portion of the drum,
thus allowing the washing water to be uniformly directed to
laundry in the drum, thereby improving washing and rinsing
efficiency and reducing a quantity of the washing water
consumed.
Although the preferred embodiments of the present
invention have been disclosed for illustrative purposes, those
skilled in the art will appreciate that various modifications,
additions and substitutions are possible, without departing
from the scope and spirit of the invention as disclosed in the
accompanying claims.