U.S. patent application number 10/604389 was filed with the patent office on 2005-01-20 for [automatic frying apparatus for both deep and shallow frying].
Invention is credited to Peng, Zheng, Xu, Zhaoxia.
Application Number | 20050011370 10/604389 |
Document ID | / |
Family ID | 34062251 |
Filed Date | 2005-01-20 |
United States Patent
Application |
20050011370 |
Kind Code |
A1 |
Xu, Zhaoxia ; et
al. |
January 20, 2005 |
[AUTOMATIC FRYING APPARATUS FOR BOTH DEEP AND SHALLOW FRYING]
Abstract
An automatic frying apparatus (100) for both deep and shallow
frying. Frying apparatus (100) comprises a container (102) having
an inner cylindrical wall (102b) installed on the central bottom
thereof, so as to emanate from the bottom to substantially the
upper portion of container (102) for holding foods and oil, a lid
(104) covering on top of container (102), a plurality of stirring
blades (108) rotatably and removably installed inside container
(102) for stirring foods, a power-drive assembly (110)
operationally coupled with blades (108) for driving blades (108)
through repeating stirring cycles, a coupling device (106) for
coupling in between assembly (110) and blades (108), a venting
device (200) for filtering and deodorizing cooking fumes, and a
blowing device (202) for forcing fresh air into frying apparatus
(100) for moisture removal from thereinside. Blades (108) sweep
across food pieces intermittently, such that blades (108) dwell for
a predetermined dwell period starting near the end of each stirring
cycle. This intermittent operation favors better agitation of food
pieces and affords relief from constant stirring of food pieces at
a higher speed. Food pieces are partially immersed in the boiling
oil, and therefore, less oil is required for frying foods, thereby,
causing less energy consumption, less fat absorption by the food,
less time for cooking, and less used oil for disposal. The frying
process is fully automatic and requires minimal human involvement
and chore.
Inventors: |
Xu, Zhaoxia; (Ypsilanti,
MI) ; Peng, Zheng; (Ypsilanti, MI) |
Correspondence
Address: |
ZHAOXIA XU
4694 SYCAMORE DR.
YPSILANTI
MI
48197
US
|
Family ID: |
34062251 |
Appl. No.: |
10/604389 |
Filed: |
July 17, 2003 |
Current U.S.
Class: |
99/409 |
Current CPC
Class: |
A47J 36/165 20130101;
A47J 37/0641 20130101; A47J 37/1257 20130101; A47J 36/38
20130101 |
Class at
Publication: |
099/409 |
International
Class: |
A47J 037/12 |
Claims
1. (canceled)
2. (canceled)
3. (canceled)
4. (canceled)
5. (canceled)
6. (canceled)
7. A frying apparatus, said frying apparatus comprising: a
container having an open top for holding foods and oil; a lid
covering on top of said container for closing up said open top of
said container; heating means for heating said foods and oil
disposed inside said container; stirring means installed inside
said container for stirring foods; a power-drive assembly
operationally coupled with said stirring means for driving said
stirring means through repeating stirring cycles; a blowing device
for forcing fresh air into said frying apparatus during frying
processes, thereby, facilitating moisture removal from inside said
frying apparatus; and a venting device for exhausting cooking
fumes.
8. A frying apparatus as defined in claim 7, wherein said venting
device includes filter means for cooking fume treatment.
9. (canceled)
10. (canceled)
11. A frying apparatus as defined in claim 7, wherein said blowing
device includes a one-way valve for preventing cooking fumes from
escaping therethrough.
12. A frying apparatus as defined in claim 7, said frying apparatus
further including control means for automatically de-energizing
said power-drive assembly near the end of each stirring cycle for a
predetermined dwell period.
13. A frying apparatus as defined in claim 7, said frying apparatus
further including control means, said control means dividing the
blowing operation of said blowing device into repeating blowing
cycles of predetermined length and automatically de-energizing said
blowing device near the end of each blowing cycle for a
predetermined dwell period.
14. A frying apparatus, said frying apparatus comprising: a
container having an open top and an upstanding inner cylindrical
wall for holding foods and oil; a lid covering on top of said
container for closing up said open top of said container; heating
means for heating said foods and oil disposed inside said
container; stirring means installed inside said container for
stirring foods; a power-drive assembly disposed below said
container and operationally coupled with said stirring means for
driving said stirring means through repeating stirring cycles; and
a coupling device having an inner cylindrical wall and an outer
cylindrical wall, engaged with each other on the upper portion
thereof, wherein said outer cylindrical wall of said coupling
device is routed over said upstanding inner cylindrical wall of
said container and the lower portion of said outer cylindrical wall
of said coupling device is engaged with said stirring means, and
wherein said inner cylindrical wall of said coupling device
includes a coupling element on the lower portion thereof for
lockably receiving a drive shaft from said power-drive
assembly.
15. A frying apparatus as defined in claim 14, wherein said
container includes co-rotation preventing means installed inside
said container on the sidewall thereof for preventing food pieces
from co-rotating with said stirring means, as said stirring means
rotates.
16. A frying apparatus as defined in claim 14, wherein said
container includes supporting means installed on the inside bottom
thereof for supporting said stirring means, thereby avoiding
excessive scraping of said stirring means on the bottom of said
container, reducing the friction therebetween, and prolonging the
life of said stirring means.
17. A frying apparatus as defined in claim 14, wherein said drive
shaft includes supporting means installed on the upper portion
thereof for operationally supporting said drive shaft against said
upstanding inner cylindrical wall of said container.
18. A frying apparatus as defined in claim 14, said frying
apparatus further including control means for automatically
de-energizing said power-drive assembly near the end of each
stirring cycle for a predetermined dwell period.
19. A frying apparatus as defined in claim 14, said frying
apparatus further including a basket having an open top and a
central aperture on the bottom thereof removably receiving said
upstanding inner cylindrical wall of said container for use to
deep-fry foods.
20. A frying apparatus, said frying apparatus comprising: a
container having an open top and a central aperture on the bottom
thereof for holding foods and oil; a lid covering on top of said
container for closing up said open top of said container; heating
means for heating said foods and oil disposed inside said
container; stirring means installed inside said container for
stirring foods; a power-drive assembly disposed below said
container and operationally coupled with said stirring means for
driving said stirring means through repeating stirring cycles, said
power-drive assembly including a drive shaft threading through said
central aperture of said container; a sealing assembly installed on
the bottom of said container for sealing between the bottom of said
container and said drive shaft; [and]wherein said sealing assembly
includes a compression-packing adapted to be squeezed against said
drive shaft from said power-drive assembly and said central
aperture on the bottom of said container for generating a sealing
thereof; and a coupling device engaged with said stirring means and
adapted for lockably receiving said drive shaft from said
power-drive assembly.
21. A frying apparatus as defined in claim 20, wherein said
container includes co-rotation preventing means installed inside
said container on the sidewall thereof for preventing food pieces
from co-rotating with said stirring means, as said stirring means
rotates.
22. (canceled)
23. A frying apparatus as defined in claim 20, wherein said
container includes supporting means installed on the inside bottom
thereof for supporting said stirring means, thereby, avoiding
excessive scraping of said stirring means on the bottom of said
container, reducing the friction therebetween, and prolonging the
life of said stirring means.
24. A frying apparatus as defined in claim 20, said frying
apparatus further including control means for automatically
de-energizing said power-drive assembly near the end of each
stirring cycle for a predetermined dwell period, and wherein said
control means controls said power-drive assembly to drive said
stirring means to perform an intermittent stirring operation across
foods.
25. A frying apparatus as defined in claim 20, said frying
apparatus further including a basket having an open top and a
central aperture on the bottom thereof removably receiving said
drive shaft for use to deep-fry foods.
26. A frying apparatus, said frying apparatus comprising: a
container having an open top, a closed bottom, and an upstanding
central shaft installed on the central bottom thereof for holding
foods and oil; a lid covering on top of said container for closing
up said open top of said container; heating means for heating said
foods and oil disposed inside said container; stirring means
installed inside said container for stirring foods; a power-drive
assembly disposed above said container and operationally coupled
with said stirring means for driving said stirring means through
repeating stirring cycles; and a coupling device having a hollow
cylindrical lower portion for removably receiving said upstanding
central shaft, wherein said hollow cylindrical lower portion of
said coupling device is engaged with said stirring means, and
wherein said coupling device includes a coupling element on the
upper portion thereof for operationally transferring rotation power
from said power-drive assembly to stirring means.
27. A frying apparatus as defined in claim 26, wherein said
container includes co-rotation preventing means installed inside
said container on the sidewall thereof for preventing food pieces
from co-rotating with said stirring means, as said stirring means
rotates.
28. A frying apparatus as defined in claim 26, wherein said
container includes supporting means installed on the inside bottom
thereof for supporting said stirring means, thereby, avoiding
excessive scraping of said stirring means on the bottom of said
container, reducing the friction therebetween, and prolonging the
life of said stirring means.
29. A frying apparatus as defined in claim 26, said frying
apparatus further including control means for automatically
de-energizing said power-drive assembly near the end of each
stirring cycle for a predetermined dwell period.
30. A frying apparatus as defined in claim 26, said frying
apparatus further including a basket having an open top and a
central aperture on the bottom thereof removably receiving said
upstanding central shaft for use to deep-fry foods.
31. (canceled)
32. (canceled)
33. (canceled)
34. A frying apparatus as defined in claim 7, said frying apparatus
further including a housing, wherein said container is removably
disposed inside said housing, and whereby it is easier to load and
unload foods and to clean said container after use.
35. A frying apparatus as defined in claim 7, wherein said venting
device is installed on said lid, and wherein said venting device
includes a fabric or paper filter for capturing the grease content
in cooking fumes.
36. A frying apparatus as defined in claim 8, wherein said filter
means includes a mesh filter for capturing the grease content in
cooking fumes, and wherein said mesh filter is washable and
reusable.
37. (original) A frying apparatus as defined in claim 36, wherein
said filter means includes a fabric or paper filter for capturing
the grease content in cooking fumes.
38. A frying apparatus as defined in claim 8, wherein said filter
means includes a fabric or paper filter for capturing the grease
content in cooking fumes.
39. A frying apparatus as defined in claim 8, wherein said filter
means includes a activated carbon filter for capturing the grease
content and removing cooking odors in cooking fumes.
40. A frying apparatus as defined in claim 14, wherein said
upstanding inner cylindrical wall of said container extends upwards
to a predetermined height above the bottom of said container, and
said frying apparatus further including a sealing assembly for
sealing between said drive shaft from said power-drive assembly and
the upper portion of said upstanding inner cylindrical wall of said
container.
41. A frying apparatus as defined in claim 40, wherein said sealing
assembly includes a compression-packing adapted to be squeezed
against said drive shaft from said power-drive assembly and the
upper portion of said upstanding inner cylindrical wall of said
container for generating a sealing thereof.
42. (canceled)
43. A frying apparatus as defined in claim 20, wherein said sealing
assembly is installed on the bottom of said container and disposed
underneath the bottom of said container.
44. A frying apparatus as defined in claim 20, wherein said sealing
assembly is installed on the bottom of said container and disposed
inside said container, wherein said compression-packing is disposed
at a predetermined height above the bottom of said container,
whereby for most applications of said frying apparatus said
compression-packing is disposed above boiling oil or hot liquids,
and whereby the requirement on said sealing assembly is
significantly reduced.
45. (canceled)
46. A frying apparatus as defined in claim 20, said frying
apparatus further including control means for controlling various
functions of said frying apparatus, whereby frying processes can be
accomplished in a programmed automatic manner for minimizing human
involvement and chore in preparing foods.
47. (canceled)
48. (canceled)
49. (canceled)
50. (canceled)
51. A frying apparatus as defined in claim 20, said frying
apparatus further including a venting device for exhausting cooking
fumes.
52. A frying apparatus as defined in claim 51, wherein said venting
device includes a mesh filter for capturing the grease content in
cooking fumes, and wherein said mesh filter is washable and
reusable.
53. A frying apparatus as defined in claim 51, wherein said venting
device includes a fabric or paper filter for capturing the grease
content in cooking fumes.
54. A frying apparatus as defined in claim 51, wherein said venting
device includes an activated carbon filter for capturing the grease
content and removing cooking odors in cooking fumes.
55. A frying apparatus as defined in claim 20, said frying
apparatus further including a blowing device for forcing fresh air
into said frying apparatus during frying processes, thereby,
facilitating moisture removal from inside said frying
apparatus.
56. (canceled)
57. A frying apparatus as defined in claim 20, said frying
apparatus further including a housing, wherein said container is
removably disposed inside said housing, and whereby it is easier to
load and unload foods and to clean said container after use.
58. (canceled)
59. A frying apparatus as defined in claim 57, wherein said drive
shaft includes a coupling mechanism disposed on the lower portion
thereof for lockably receiving a shaft from said power-drive
assembly.
Description
BACKGROUND OF INVENTION
[0001] This invention generally relates to cooking/food processing
apparatuses. More specifically, this invention relates to automatic
frying apparatuses for both deep and shallow frying.
[0002] Fried foods, such as fried shrimp, fried fish, fried
chicken, etc., are tasteful. Two of the most important
characteristics of fried foods are: outside, golden and crispy; and
inside, juicy and tender. There are some issues associated with
preparing fried foods at home.
[0003] First, the contact of moisture-containing raw foods with hot
oil produces grease splattering. Most times, the splattering
liquids and food particles reach out of frying apparatuses to
considerable distances. These will not only mess up stovetops and
surrounding surfaces but also create undue oil burn injuries to the
people who are preparing fried foods. The problem of grease fires
in the kitchen as well as severe oil burns to people has been well
documented.
[0004] Second, oil vapor is produced when oil is heated. The people
who are preparing fried foods involuntarily inhale considerable
amount of cooking fumes during the cooking process. Oil vapor is
harmful to human health and might pose long-term health threats to
the people who expose themselves to oil vapor on a very regular
base.
[0005] Third, the oil vapor generated in the cooking process might
easily reach much farther in the kitchen or even other rooms and
deposit on the furniture, paintings, electrical appliances, etc.,
causing long-term hazards to home environment.
[0006] Fourth, on the other hand, there is an ever-increasing
concern over the amount of oil or fat in one's diet for general
public. In particular, a low fat diet is desirable in light of
related health concerns. Generally, fried foods prepared using
conventional methods and cooking wares contain more fat than other
foods.
[0007] Many products of deep-frying apparatuses or food processing
apparatuses are on the market, including the electric frying
apparatus taught by U.S. Pat. No. 6,365,878, issued to Lau, on Apr.
2, 2002. These products are equipped with vertically moving baskets
and generally require the food to be immersed deep in the frying
oil; which means that large quantity of oil is required. The high
quantity of oil needed for proper cooking also means high operating
cost due to high energy consumption and longer time for cooking.
The quantity of oil absorption by the food is prohibitively high,
as well.
[0008] The disposal of used oil is going to be an environmental
issue. Food processing businesses and restaurants might be able to
afford expensive equipment for the disposal or treatment of used
oil. But general public will find it difficult in dealing with
large quantity of used oil.
[0009] Another issue is that the user has to repeatedly stir or
turn the food around to separate the food pieces during frying,
such that the food can be cooked more uniformly.
[0010] Over years, various devices have been developed to address
these problems associated with frying at home.
[0011] U.S. patent application Ser. No. 10/249,240, filed by
myself, on Mar. 25, 2003, teaches a forced venting fry utensil. The
fry utensil comprises a container for holding foods and oil, a lid
covering on top of the container, a blowing device for forcing
fresh air into the fry utensil for facilitating the evaporation of
food moisture, and a venting device for filtering and deodorizing
cooking fumes.
[0012] The aforementioned prior art is concentrating on the issue
of splattering of hot grease and food particles and cooking fume
treatment. However, It fails to address the necessity of automating
frying processes. Without frying process automation, especially at
home, consumers have to stir the food or turn the food over in the
middle of frying processes. In this case, the generation of hot oil
splattering and the escape of oil vapor into the room are still
inevitable.
[0013] Some patents have been granted in the area of automatic
frying apparatuses.
[0014] U.S. Pat. No. 5,027,697, issued to De Longhi, on Jul. 2,
1991, teaches a rotating oblique basket fryer for cyclic immersion
cooking; which facilitates the elimination of moisture in the food,
accelerates the heat exchange process, and favors uniform operating
temperatures.
[0015] U.S. Pat. No. 5,543,166, issued to Masel, et al., on Aug. 6,
1996, describes a cooking appliance including a drum for receiving
the food articles to be cooked. The appliance is characterized in
that the finished food is spun about a central axis to spin out
unwanted excess of oil.
[0016] U.S. Pat. No. 5,611,265, issued to Ronci et al., on Mar. 18,
1997, describes a combination of fryer and charbroiler food cooking
apparatus. The excessive oil is separated from the fried foods
using centrifugal means.
[0017] U.S. Pat. No. 6,453,801, issued to Masel, et al., on Sep.
24, 2002, teaches a cooking appliance and method for cooking food
articles by means of a rotary drum. The appliance is characterized
in that a liquid container is selectively movable to a raised or
lowered position to adjust the oil level with respect to the food
articles.
[0018] The aforementioned prior arts are concentrating on automatic
frying apparatuses with special emphasis on low fat frying. The low
fat characteristic is mostly achieved by mechanical means, e.g.,
centrifugal means. This makes the prior art apparatuses less
appealing because mechanical separation devices generally require a
large size of the frying apparatus. The manufacturing cost is
higher and consequently the higher prices the general public pays
to buy these apparatuses. Another reason why these prior art
apparatuses do not prevail lies on the fact that the mechanisms for
achieving targeted objectives are, to some extent, too complicated,
which, again, drives up the manufacturing cost. The effort spent on
cleaning these apparatuses after use is another important factor.
In addition, they fail to address the issue of cooking fume hazards
and moisture removal from inside the frying apparatus.
[0019] Low fat frying can be, alternatively, achieved by means of
how the food is processed. The key point is that the moisture
content residing in the raw food, especially in the surfaces of
food pieces, has to be removed as quickly as possible. The removal
of the surface moisture content greatly favors less fat absorption,
less time for frying, less energy consumption, and foods of great
looking, taste, and texture.
[0020] U.S. patent application Ser. No. 10/249,399, filed by
myself, on Apr. 5, 2003, teaches an automatic frying apparatus
having a perforated rotary drum for holding and frying foods
removably installed inside a container, and a forced venting system
for forcing fresh air into the frying apparatus for facilitating
food moisture evaporation and cooking fume treatment. The frying
apparatus overcomes all the shortcomings of prior art products.
[0021] However, all the prior arts, including the one proposed by
myself in U.S. patent application Ser. No. 10/249,399, have a very
important drawback; they are specifically addressing the issues
associated with deep-frying. These prior art products cannot be
used for shallow frying, in another word, stir-frying, which is a
widely used food preparing/processing method, especially in
oriental cuisine. Shallow frying requires constant stirring.
Therefore, grease splattering and oil vapor hazards are among the
most important issues to deal with. On the other hand, shallow
frying requires much more human effort, whereby automation is
highly desired.
[0022] Therefore, it remains desirable to provide frying
apparatuses that can be used for both deep and shallow frying, that
are automatic to minimize the human involvement or chore during the
frying process, that favors homogeneous heating of foods, that
require minimal quantity of oil for frying foods, that can
effectively and efficiently evaporate the surface moisture content
of food pieces to achieve the characteristic of low fat absorption
and great looking, taste, and texture of foods, that are
inexpensive to manufacture and simple and easy to use, and also
that are environment, people, and home friendly.
SUMMARY OF INVENTION
[0023] Accordingly, the present invention is an automatic frying
apparatus for both deep and shallow frying. This frying apparatus
comprises a container having an open top for holding foods and oil,
a lid covering on top of the container for closing up the open top,
a plurality of stirring blades rotatably and removably installed
inside the container, on the central bottom, a power-drive assembly
operationally coupled with these stirring blades for driving these
stirring blades through repeating stirring cycles for facilitating
homogeneous heating, a blowing device for forcing fresh air into
the frying apparatus for facilitating evaporation of moisture
content residing in the surfaces of food pieces, and a venting
device for filtering and de-odorizing cooking fumes.
[0024] These stirring blades sweep across food pieces in an
intermittent operation, in which they dwell for a predetermined
dwell period near the end of each stirring cycle. This intermittent
operation affords relief from constant stirring of food pieces at a
higher speed, thereby favoring foods of great texture and looking.
Food pieces are partially immersed in the boiling oil, and
therefore, less oil is required for frying. Cooking fumes are
treated right before leaving the frying apparatus, whereby, this
fry apparatus of the present invention is people and home
environment friendly.
[0025] Accordingly, the followings are some of the objects,
features, and advantages of the present invention:
[0026] It is an object of the present invention to provide a frying
apparatus for use to prepare tasteful fried foods for both deep and
shallow frying.
[0027] It is another object of the present invention to provide a
frying apparatus that is automatic in separating, stirring, and
turning over food pieces for facilitating moisture evaporation and
uniform heating, so as to minimize the human involvement or chore
during the frying process.
[0028] It is a further more object of the present invention to
provide a frying apparatus that is environment, people, and home
friendly.
[0029] It is a still further more object of the present invention
to provide a frying apparatus that requires minimal quantity of oil
for frying foods, and consequently causes less energy consumption,
less used oil for disposal, and less time for cooking.
[0030] It is a still further more object of the present invention
to provide a frying apparatus that is of durable and reliable
constructions, easily and efficiently manufactured and marketed,
and at the same time economically available to the general
public.
[0031] It is a feature of the present invention that this frying
apparutus has a plurality of stirring blades rotatably and
removably installed on the central bottom of the container for
stirring foods. These blades sweep across food pieces in an
intermittent operation, in which they dwell for a predetermined
interval of time near the end of each sweeping cycle and then
automatically begin another cycle of operation. This intermittent
operation affords relief from constant stirring of food pieces at a
higher speed, thereby favoring foods of great texture and
looking.
[0032] It is another feature of the present invention that this
frying apparatus has a forced venting system including a blowing
device to force fresh air into the frying apparatus for
facilitating moisture removal from thereinside and a venting device
for removing the oil vapor content in the grease-laden air
generated during the frying process before the air is exhausted
into the room.
[0033] It is a further more feature of the present invention that
the food to be fried is partially immersed in the boiling oil,
thereby reducing the requirement on the quantity of oil for proper
frying, and consequently this frying apparatus of the present
invention consumes less energy and takes less time for cooking.
[0034] It is a still further more feature of the present invention
that this frying apparatus fries foods in a programmed automatic
manner; therefore, minimal human involvement or chore is
rendered.
[0035] It is an advantage of the present invention that this frying
apparatus is virtually hand-free for frying foods and can be used
for both deep and shallow frying.
[0036] It is another advantage of the present invention that this
frying apparatus is environment, people, and home friendly.
[0037] It is a further more advantage of the present invention that
this frying apparatus is easy to operate, cheap to manufacture, and
providing large value to businesses and general public.
[0038] Further more features and advantages of the present
invention will be readily appreciated, as the same becomes better
understood after reading the subsequent description when considered
in connection with the accompanying drawings.
BRIEF DESCRIPTION OF DRAWINGS
[0039] FIG. 1 illustrates a cross-sectional view of an embodiment
of the present invention, a frying apparatus 100.
[0040] FIG. 2 illustrates an exploded cross-sectional view of
coupling device 106.
[0041] FIG. 3 illustrates an exploded cross-sectional view of
blades 108.
[0042] FIG. 4 illustrates an exploded cross-sectional view of
venting device 200.
[0043] FIG. 5 illustrates an exploded cross-sectional view of
blowing device 202.
[0044] FIG. 6 illustrates an exploded cross-sectional view of
one-way valve 218 of FIG. 5.
[0045] FIG. 7 illustrates a blocked diagram of control circuit 152
for frying apparatus 100.
[0046] FIG. 8 illustrates a schematic diagram of control circuit 50
for providing the intermittent operation of blade sweeping for
frying apparatus 100.
[0047] FIG. 9 illustrates a schematic diagram of control circuit 70
for providing the intermittent venting operation for frying
apparatus 100.
[0048] FIG. 10 illustrates a perspective view of perforated basket
168 for use with frying apparatus 100.
[0049] FIG. 11 illustrates a cross-sectional view of basket 168 in
an operation position.
[0050] FIG. 12 illustrates an alternative design of frying
apparatus 100 of FIG. 1, a frying apparatus 100a.
[0051] FIG. 13 illustrates a cross-sectional view of another
embodiment of the present invention, a frying apparatus 300.
[0052] FIG. 14 illustrates an exploded cross-sectional view of seal
assembly 308 of FIG. 13.
[0053] FIG. 15 illustrates an exploded cross-sectional view of an
alternative design of seal assembly 308 of FIG. 14.
[0054] FIG. 16 illustrates an alternative design of frying
apparatus 300 of FIG. 13, a frying apparatus 300a.
[0055] FIG. 17 illustrates a cross-sectional view of a further more
embodiment of the present invention, a frying apparatus 400.
[0056] FIG. 18 illustrates an alternative design of frying
apparatus 400 of FIG. 17, a frying apparatus 400a.
DETAILED DESCRIPTION
[0057] Reference is made to FIG. 1, which illustrates a
cross-sectional view of an embodiment of the present invention, a
frying apparatus 100. Frying apparatus 100 comprises a container
102, a lid 104, a coupling device 106, a plurality of stirring
blades, generally designated as 108, a power-drive assembly 110, a
venting device 200, and a blowing device 202.
[0058] Container 102, having an open top, an outer wall 102a, and
an upstanding inner cylindrical wall 102b, is provided for holding
foods and oil. Cylindrical wall 102b is installed on the central
bottom of container 102, so as to emanate from the bottom thereof
upward to substantially the open top, forming a central aperture
therein. Container 102 is, preferably, coated with a non-stick
material.
[0059] A plurality of co-rotation preventing blades, generally
designated as 112, is installed inside container 102, on outer wall
102a, for preventing the food from co-rotating with stirring blades
108, as blades 108 rotate. Blades 112, disposed on positions
slightly higher than blades 108, generally extend vertically. The
size of blades 112 can be substantially different based on specific
designs of container 102.
[0060] A heating element 114, installed on the outside surface of
the bottom of container 102, is provided for heating foods and oil
disposed inside container 102. Heating element 114 is in a
heat-transferable condition, e.g., in physical contact, with the
bottom of container 102, such that when heating element 114 heats
up upon connection with an electricity source, foods and oil
therein will also heat up. Heating element 114 can be electrical
resistance type heaters or many other types, such as high-intensity
infrared lamps, as known to those skilled in the art and suggested
by this invention disclosure.
[0061] A container support 116, installed on the bottom and side of
container 102, is provided for furnishing a bottom support for
container 102, such that frying apparatus 100 can stand on a flat
surface, e.g., a kitchen counter top. Another function of support
116 is insulating the bottom of container 102. The sidewall of
support 116 can extend upward, covering substantially large area of
outer wall 102a of container 102 for minimizing heating energy
loss. In this case, support 116 serves as an outer housing.
[0062] A temperature sensor 118 is provided for measuring the
temperature of the frying oil, as an input variable to be
controlled. Sensor 118 is installed at an appropriate position on
the bottom of container 102, or any other suitable positions. When
the temperature of the frying oil is above the user's desired one,
the electrical power to heating element 114 will be shut down to
better meet the user's desired frying requirement and to save
energy.
[0063] Lid 104 is provided for covering on top of container 102 for
closing up the open top thereof. Lid 104 can be made of a
transparent material, or a metal material but has an observation
window (not shown), made of a transparent material, for observing
the frying process by the user.
[0064] An opening 104a is provided on lid 104, disposed at a
suitable location, for adding ingredients to the food inside
container 102 by the user in the middle of frying processes. A cap
104b is provided for covering up opening 104a.
[0065] FIG. 2 illustrates an exploded cross-sectional view of
coupling device 106. Coupling device 106, having an outer
cylindrical wall 106a and an inner cylindrical wall 106b, is
provided for coupling a main shaft 120 from power-drive assembly
110 and stirring blades 108 for transferring rotation power. Walls
106a and 106b are substantially co-axial to cylindrical wall 102b
of container 102 and are fixedly connected together on the upper
portion thereof. The lower portion of wall 106a is engaged with
blades 108. The lower portion of wall 106b has a cross-channel
coupling element 106c, or other types of coupling elements, which
lockably receives main shaft 120 and a main shaft pin 122. Pin 122
is mounted on the upper portion of main shaft 120, running across a
diameter thereon for coupling main shaft 120 and coupling element
106c. In operation, wall 106a is routed over wall 102b and wall
102b is routed over wall 106b. The upper portion of main shaft 120
threads inside wall 106b. Minimal clearance is desired among these
walls for ideal performance.
[0066] Blades 108, rotatably and removably installed inside
container 102 on the central bottom thereof, are provided for
stirring foods. There is a central aperture on blades 108 to permit
threading over cylindrical wall 102b.
[0067] A stirring blade spacer 124, fixedly installed on the
central bottom of container 102 around the bottom portion of wall
102b, is provided for supporting blades 108.
[0068] FIG. 3 illustrates a cross-sectional view of blades 108 in
relation to the bottom of container 102. The cross-section
generally forms a plow-like configuration. The front portion
thereof, generally designated as 108a, is close to the bottom of
container 102 with a small predetermined clearance for better
scooping up food pieces. The rear portion thereof, generally
designated as 108b, extending gradually upward, serves for lifting
up/turning over food pieces. The clearance between front portion
108a and the bottom of container 102 is minimized for ideal
performance.
[0069] However, when the clearance is small, it is inevitable that
blades 108 will scrape on the bottom of container 102, causing
worn-out of blades 108 and energy loss due to friction of large
area. To deal with this dilemma, a plurality of circular
protrusions, generally designated as 102c, fixedly installed on the
bottom of container 102, is proposed in this invention disclosure.
Reference is made to FIGS. 1 and 2 for the configuration of
protrusions 102c. Protrusions 102c provide further support to
blades 108, in addition to spacer 124, which is more clearly shown
in FIG. 2. A predetermined small width of protrusions 102c is
desired for providing adequate support and, at the same time,
minimizing friction. In the case for a container coated with a
non-stick material, the top surface of protrusions 102c is,
preferably, not coated. Local areas on blades 108, which are in the
vicinity of protrusions 102c, can have a different material for
durability consideration. The height of protrusions 102c is,
preferably, small, e.g., less than 1 mm, for ideal performance of
blades 108 in scooping up food pieces and avoiding sticking.
Protrusions 102c can readily have many other configurations, or
pattens.
[0070] The speed, at which blades 108 sweep across food pieces, is
important. For too low speeds, blades 108 cannot scoop up food
pieces and therefore food pieces cannot be agitated adequately to
achieve the desired effect of homogeneous heating and the
evaporation of food moisture. Corotation of food pieces with blades
108, as blades 108 rotate, is going to be a big issue. Therefore, a
higher speed is desirable for good performance. But, on the other
hand, for continuous operation of blade sweeping, when the speed is
high, food pieces are agitated too much, for too long time, such
that the crispy surfaces of food pieces are damaged, which, in
turns, causes frying oil to be wasted due to too many tiny food
particles in the oil. In addition, the worn-out of blades 108 and
energy loss due to friction between blades 108 and the bottom of
container 102 are going to be serious problems.
[0071] To solve this dilemma, an intermittent operation of blade
sweeping is proposed in this invention disclosure. In this
intermittent operation, blades 108 dwell for a predetermined
interval of time after one or two rounds of sweeping, referred as
one stirring cycle, and then automatically begin another cycle of
operation. This intermittent operation affords relief from constant
stirring of food pieces at a higher speed, prolongs the life of
blades 108 and power-drive assembly 110, and saves some energy
required for driving blades 108, as compared with the continuous
operation. This intermittent operation also favors foods of great
texture because during the dwell period, the food pieces have
adequate time to form crispy surfaces; which, in turns, favors
foods of great looking. A computer control method and an electronic
control circuit for achieving this intermittent operation are going
to be disclosed later on, when the control portion of frying
apparatus 100 is discussed.
[0072] Reference is, again, made to FIG. 1. Power-drive assembly
110 includes a drive motor 126 and main shaft 120.
[0073] A motor housing 128, having an open top, is provided for
housing motor 126. Motor housing 128 is installed on the central
bottom of support 116. A cap 130 is provided for covering on top of
motor housing 128 for closing up the open top thereof. There is a
central aperture on cap 130 for permitting main shaft 120 to thread
therethrough.
[0074] Motor 126 is installed inside motor housing 128 through a
bracket 132 and is operationally connected to a DC adapter 134.
[0075] Main shaft 120 is operationally coupled with motor 126,
directly for a low-speed motor or via some gears or belt-pulley
devices for a high-speed motor. Main shaft 120 is substantially
co-axial to cylindrical wall 102b and threads therein, so as to
emanate from the bottom of container 102 to substantially the upper
portion of wall 102b.
[0076] Reference is made to FIG. 2, again. On the upper portion of
main shaft 120, coupling pin 122 is provided for the engagement
with coupling element 106c of coupling device 106. Pin 122 has a
predetermined length so as to conveniently slide in the opening on
the lower portion of cylindrical wall 106b for removably locking on
coupling element 106c.
[0077] A plurality of main shaft supporting elements, generally
designated as 136, installed on the upper portion of main shaft
120, is provided for further supporting main shaft 120, against
cylindrical wall 102b. Elements 136 have a ring-like configuration
and are slidably threaded inside cylindrical wall 102b, together
with main shaft 120. The clearance between elements 136 and
cylindrical wall 102b is minimized for ideal performance. Bearings
are ideal options for elements 136 for minimizing power loss due to
friction.
[0078] Reference is, now, made to FIG. 4 and FIG. 5, which
illustrate an embodiment of a forced venting system including a
venting device 200 and a blowing device 202 of FIG. 1.
[0079] Venting device 200 includes a venting conduit 206 and a
venting filter 208. The first end of venting conduit 206 is mounted
on lid 104. There is an opening on lid 104 inline with venting
conduit 206 for allowing cooking fumes to be forced out
therethrough. Venting conduit 206 also serves as a bracket for
holding venting filter 208. Venting filter 208 is removably engaged
with the second end of venting conduit 206. Venting filter 208
further includes a disposable paper filter 208a and/or a disposable
activated charcoal filter 208b, together, as an integrated
filter.
[0080] Venting filter 208 is provided to trap the grease impurities
in the grease-laden air forced out from inside frying apparatus
100. Venting filter 208 is, preferably, made of one or multiple
layers of metal meshes, such as aluminum ones. Metal meshes have
different sizes of meshes and overlap each other. When cooking
fumes pass therethrough, the oil particles will be trapped thereon.
Filters 208a and 208b are provided to further remove the remaining
oil vapor and chemical contents in the cooking fumes and for
removing the cooking fume odors before the air is exhausted into
the room.
[0081] Blowing device 202 includes an in-take conduit 210, a
blowing motor 214, a fan 216, and a one-way valve 218.
[0082] The first end of in-take conduit 210 is mounted on the upper
portion of container 102. There is an opening on the sidewall of
container 102 inline with in-take conduit 210 for allowing fresh
air to be forced into frying apparatus 100. There is an aperture
212 on in-take conduit 210. Aperture 212 functions as an air inlet.
An inlet conduit 210a extends from aperture 212 to the outside
space, such that fresh air from outside atmosphere can be readily
drawn into frying apparatus 100. A filter 210b, made from metal
meshes, is provided for preventing some large particles from being
drawn therein. In-take conduit 210 also serves as a bracket for
holding motor 214 in position. Motor 214 is removably coupled with
the second end of in-take conduit 210. Fan 216 is connected to
motor 214 on the shaft and inserted inside in-take conduit 210.
Motor 214 is operationally connected to adapter 134, which is shown
in FIG. 1.
[0083] As shown in FIG. 6, which illustrates an exploded
cross-sectional view of one-way valve 218 of FIG. 5. Valve 218
includes a valve housing 220, a valve body 222, a covering piece
224, and a biasing spring 226. Valve housing 220 is engaged with
the first end of in-take conduit 210. There are apertures on valve
housing 220 for allowing air to pass therethrough. Valve body 222
is engaged with the open end of valve housing 220. There are
apertures on valve body 222 for allowing air to pass therethrough.
Covering piece 224 covers on valve body 222 for closing and opening
valve 218. There is a central protrusion on covering piece 224. The
central protrusion is slidably inserted into a central aperture on
valve body 222, such that the protrusion can slide along the
central aperture for a predetermined distance. Spring 226 is
attached between the protruding end of the protrusion and valve
housing 220, such that spring 226 is biased in slight tension,
thereby, pulling covering piece 224 toward/against valve body 222
for closing up valve 218.
[0084] When blowing device 202 is in working condition, the air
pressure generated by fan 216 forces covering piece 224 to slide
away from valve body 222, such that valve 218 is in opening state
for allowing air to pass therethrough. Valve 218 is provided for
preventing cooking fumes inside frying apparatus 100 from escaping
through blowing device 202 while blowing device 202 is temporarily
not in working condition.
[0085] Those skilled in the art will appreciate in view of this
invention disclosure that many other suitable valve designs are
readily applicable for this application of the present
invention.
[0086] Venting device 200 and blowing device 202 can be
alternatively installed on frying apparatus 100 at many other
positions. For example, venting device 200 can be alternatively
installed on the upper portion of container 102 and blowing device
202 can be alternatively mounted on lid 104. These variations are,
therefore, covered by this invention disclosure.
[0087] Venting device 200 is provided for cooking fume treatment.
Compared with prior art products, which allow cooking fumes to
escape freely, this centralized venting system design vents cooking
fumes in a controlled manner, such that heating energy is better
preserved for a more efficient frying apparatus.
[0088] Blowing device 202 is provided for forcing moisture content
out of frying apparatus 100, especially at the early stage of a
frying process, such that frying apparatus 100 can fry foods of
great taste, great texture, and great looking. This also favors
less cooking time and, as a result, less energy consumption.
However, there is some heating energy loss associated with using
blowing device 202. Therefore, the use of blowing device 202 should
be in a controlled manner.
[0089] Stronger blowing favors better inside airflow for better
facilitating moisture removal. However, Continuously strong blowing
will cause excessive heating energy loss. To solve this dilemma, an
intermittent venting operation is proposed in this invention
disclosure. In this intermittent venting operation, fan 216 dwells
for a predetermined interval of time near the end of a blowing
cycle, e.g., of 10 seconds, and then automatically begins another
cycle of operation. An electronic control circuit for achieving
this intermittent operation is going to be disclosed later on, when
the control portion of frying apparatus 100 is discussed.
[0090] Immediately after the frying is satisfactorily accomplished,
the food is still sizzling hot and there is still residual cooking
fume residing inside frying apparatus 100. Blowing device 202 can
be used to bring in fresh air to cool the food down to a
predetermined temperature and, at the same time, to purge the
residual cooking fumes out through venting device 200. This process
greatly favors safety of food handling, home environment
protection, and foods of great texture and looking.
[0091] The above-discussed forced venting system is good for both
deep and shallow frying. For deep-frying it facilitates the
evaporation for food surface moisture. For shallow frying,
especially for frying vegetables, it favors foods of great looking.
It is a well-known fact that when fried using a conventional frying
pan with the lid covering on top thereof, green vegetables tend to
become yellowish.
[0092] Reference is made to FIG. 1, again. A control housing 138 is
provided for housing a control module 150. Control housing 138 is
installed on the sidewall of container 102.
[0093] Control module 150, installed inside housing 138, is
provided for controlling various functions of frying apparatus 100,
such as the oil temperature for frying foods, motor speeds for
rotating blades 108, and the speed at which blowing motor 214 is
rotating.
[0094] Control module 150 includes a control circuit 152, as the
blocked construction diagram shown in FIG. 7. Circuit 152 comprises
a microcomputer 154, which controls various functions of frying
apparatus 100, a relay 156, which activates heating element 114, a
relay 158, which activates motor 126, and a relay 160, which
activates motor 214.
[0095] Microcomputer 154 is provided with ROM and RAM for data
memory, and further provided with I/O ports A/D converters as
interfaces. The aforementioned ROM's comprises a ROM 162 containing
control programs related to the performance of all frying processes
and a ROM 164, which memorizes referenced data.
[0096] Temperature sensor 118 is provided for measuring the oil
temperature, which is taken by microcomputer 154, as an input
variable to be controlled. When the temperature of the frying oil
is above the user's desired one, the electrical power to heating
element 114 will be shut down by relay 156 to better meet the
user's desired frying requirement and to save energy.
[0097] Computer 154 can be such programmed that relay 158 activates
motor 126 intermittently with a bias toward a longer dwell after
each stirring cycle of one or two rounds of rotation. In the same
manner, an intermittent venting operation can be programmed with
relay 160 activating motor 214 intermittently.
[0098] DC adapter 134 is installed inside control housing 138, as
shown in FIG. 1. Adapter 134 provides electricity power to control
circuit 152 and elements, like indicators, beepers, LCD, etc., and
to motors 126 and 214, as well.
[0099] A control panel 166, attached to control housing 138, as
shown in FIG. 1, is provided for supporting elements, like
switches, indicators, adjusting knobs, beepers, LCD, and so on.
[0100] Reference is made to FIG. 8, which illustrates a schematic
diagram of a control circuit 50 for providing the intermittent
operation of blade sweeping for frying apparatus 100.
[0101] As shown in FIG. 8, drive motor 126 is operationally coupled
with blades 108 for providing rotation power. Motor 126 has a first
terminal, which is connected to V-, the negative pole of a power
source, e.g., DC adapter 134, which is shown in FIG. 1, and a
second terminal, which is connected to the collector terminal of a
PNP bipolar transistor 51. The emitter terminal of transistor 51 is
connected to V+, the positive pole of a power source, e.g., DC
adapter 134, which is shown in FIG. 1. Associated with motor 126 is
a linkage mechanism 52, which cooperates with a single pole, double
throw switch 53, such that the shaft angle of motor 126 controls
the switching position. Switch 53 includes a single pole 54, which
is connected to the first end of a capacitor 55. Pole 54 may be
switched alternately between two throw positions as represented by
RUN and REST. The reference RUN refers generally to the position of
blades 108 when in sweeping. On the other hand, the reference REST
refers generally to the position of blades 108 when in dwelling.
The RUN position represents substantially a large portion of a
whole round of rotation angle of the motor shaft, e.g., over 80%.
The RUN position is associated with V- and the REST position is
associated with V+.
[0102] A main switch 56 is provided for activating and deactivating
the intermittent operation provided by circuit 50. Switch 56 has a
first terminal connected to V- and a second terminal connected to
the first end of a variable resistor 58.
[0103] The second end of capacitor 55 is connected to the second
end of resistor 58. Also connected to the second end of capacitor
55 are the base of transistor 51 and the second end of a resistor
59. The first end of resistor 59 is connected to the first terminal
of a STIR switch 60, which can activate a STIR feature, a manually
activated continuous operation. The second terminal of switch 60 is
associated with V-. The first end of resistor 59 is also connected
to the second end of a capacitor 61. The first end of capacitor 61
is connected to V-.
[0104] Switch 60 is a push button switch for activating the STIR
feature. When switch 60 is pushed, the two terminals are connected,
which causes the connection of the first end of resistor 59 to V-
and, at the same time, causes capacitor 61 to be
short-circuited.
[0105] With switch 56 in the activated position and switch 60 in
the deactivated position, circuit 50 will operate blades 108
intermittently with a variable dwell period at the end of each
sweeping cycle. This intermittent operation is achieved through the
circuit of transistor 51, switch 53, capacitor 55, and resistor
58.
[0106] Now, to start with, suppose motor 126 has not been operating
because switch 56 has been in the deactivated position. Also
suppose switch 53 has been in the REST position, and thus capacitor
55 has been discharged.
[0107] When switch 56 is activated, the potential at the second end
of resistor 58 will be lowered to cause transistor 51 to switch to
conductive state, thereby energizing motor 126. As soon as motor
126 begins to rotate, switch 53 will be thrown to the RUN position,
which causes the first end of capacitor 55 to be connected to V-.
Capacitor 55 will then begin to charge so as to make the second end
of capacitor 55 positive with respect to the first end thereof.
Sufficient base current will be provided through the base of
transistor 51 to cause transistor 51 to remain conductive even
after capacitor 55 becomes fully charged, thereby causing motor 126
to continue to rotate throughout a full rotation cycle until switch
53 is cycled back to the REST position. When switch 53 cycles back
to the REST position, the first end of capacitor is then connected
to V+ and capacitor 55 begins to discharge through resistor 58
until the potential at the second end of resistor 58 becomes
sufficiently negative relative to V+. During this period of time,
transistor 51 is switched to and remains in non-conductive state,
thereby stopping motor 126 for a predetermined interval of time.
And then, sufficient base current flow resumes, causing transistor
51 to become conductive again, and a new cycle starts.
[0108] The length of the dwell interval is determined by the time
required for capacitor 55 to discharge. Proper selection of
capacitor 55 and resistor 58 will provide desirable dwell
intervals.
[0109] With resistor 59 and capacitor 61 in addition, a manually
activated continuous blade-sweeping feature can be achieved in
addition to and in combination with the controllable variable dwell
feature. This performance feature is achieved regardless of whether
switch 56 is in the activated position or not when switch 60 is
pushed. Moreover, it will be seen if switch 56 is in the activated
position when switch 60 is pressed, there will be an immediate
override of the intermittent operation. The continuous operation
will keep on going without any dwell for a predetermined number of
cycles, for example, one or two, after switch 60 is released,
before the intermittent operation is resumed. If switch 56 is in
the deactivated position when switch 60 is pressed, motor 126 will
immediately start to rotate. After switch 60 is released, motor 126
will continue for a predetermined number of continuous sweeping
cycles and then stops.
[0110] When switch 60 is pressed, the first end of resistor 59 is
connected to V-. This allows sufficient current to flow through the
base of transistor 51 to switch transistor 51 to conductive state,
thereby causing motor 126 to start and operate. By proper selection
of the value of resistor 59, this mode of operation will occur
regardless of the positions of switches 53 and 56, so long as
switch 60 is depressed.
[0111] At the same time, pressing switch 60 causes capacitor 61 to
be short-circuited such that any charge stored therein is
discharged through the short circuit to V-. When switch 60 is
released, the current flow out of the base of transistor 51 will
continue through discharged capacitor 61 until capacitor 61
recharges. As a result, transistor 51 will continue in conductive
state and motor 126 will continue to operate at the normal speed.
Transistor 51 will continue in conductive state for a predetermined
period of time based on the time constant provided by resistor 59
and capacitor 61, which are preferably selected to provide one or
two continuous sweeping cycles without any dwell after switch 60 is
released.
[0112] One important point worth mentioning is that if power-drive
assembly 110 has a rotation reduction mechanism, linkage 52 should
be set between the output shaft of assembly 110 and switch 53,
instead of between motor 126 and switch 53.
[0113] If multiple rounds of sweeping are desired for a stirring
cycle, before one dwell period, e.g., two rounds of sweeping before
one dwell period, a pair of gears, or some other mechanisms, should
be provided, with the smaller one installed on the output shaft and
the larger one cooperating with switch 53. The transfer-ratio
should be 1:2.
[0114] The intermittent operation of blade sweeping can be
alternatively achieved using a mechanically controlled timer, e.g.,
a spring-driven timer (not shown). Numerous discrete contact poles
can be provided on a circular plate, such that when a needle is
rotating around a central shaft, the needle engages with each
contact pole in sequence. The angle range of each pole represents a
stirring cycle. At the end of each stirring cycle, there is a
predetermined dwell period, which is represented by the angle range
in between two adjacent poles.
[0115] Reference is made to FIG. 9, which illustrates a schematic
diagram of a control circuit 70 for providing the intermittent
venting operation for frying apparatus 100.
[0116] As shown in FIG. 9, blowing motor 214 is operationally
coupled with fan 216 for forcing fresh air into frying apparatus
100. Motor 214 has a first terminal, which is connected to V-, and
a second terminal, which is connected to the collector terminal of
a PNP bipolar transistor 71. The emitter terminal of transistor 71
is connected to V+. The base of transistor 71 is connected to the
second end of a variable resistor 72. The first end of resistor 72
is connected to the second end of a capacitor 73. The first end of
capacitor 73 is connected to V-.
[0117] Also connected to the first end of resistor 72 are the
second terminal of a magnetically activated switch 74 and the first
terminal of a VENT switch 75. The first terminal of switch 74 and
the second terminal of switch 75 are connected to V-.
[0118] Switch 74 is provided for activating and deactivating the
intermittent venting operation provided by circuit 70. Switch 74
cooperates with motor 126, such that when motor 126 is in working
state, switch 74 is activated and remains in activated condition
until motor 126 ceases to work. Switch 75 is a push button switch,
which is provided for activating a manually activated continuous
venting feature.
[0119] When either switch 74 or switch 75 is activated, the first
end of resistor 72 is connected to V- and, at the same time,
capacitor 73 is short circuited to V-.
[0120] With switch 74 in the activated position and switch 75 in
the deactivated position, circuit 70 will operate fan 216
intermittently with a variable dwell period at the end of each
venting cycle. This intermittent venting operation is achieved
through the circuit of transistor 71, resistor 72, capacitor 73,
and switch 74, which is conditioned by motor 126.
[0121] When motor 126 is in working state, switch 74 is activated,
such that the first end of resistor 72 is connected to V-, and
capacitor 73 is short circuited to V-. The potential at the second
end of resistor 72 is lowered to cause transistor 71 to switch to
conductive state, thereby energizing motor 214. As soon as motor
126 stops, switch 74 is deactivated. The current flow out of the
base of transistor 71 will continue through discharged capacitor 73
until capacitor 73 recharges. As a result, transistor 71 will
continue in conductive state and motor 214 continue to operate at
the normal speed. Transistor 71 will continue in conductive state
for a predetermined period of time based on the time constant
provided by resistor 72 and capacitor 73, which are preferably
selected to provide a multiple of a sweeping cycle of blades 108,
e.g., five continuous blade sweeping cycles. Motor 214 then dwells
for a predetermined interval of time until the next cycle of the
intermittent operation of blades 108 starts, when motor 126
activates switch 74, again.
[0122] With switch 75 in addition, a manually activated continuous
venting performance feature can be achieved in addition to and in
combination with the controllable variable dwell feature. This
performance feature is achieved regardless of whether switch 74 is
in the activated position or not when switch 75 is pushed.
Moreover, it will be seen if switch 74 is in the activated position
when switch 75 is pressed, there will be an immediate override of
the intermittent venting operation. The continuous operation will
keep on going without any dwell for a predetermined interval of
time after switch 75 is released, before the intermittent venting
operation is resumed. If switch 74 is in the deactivated position
when switch 75 is pressed, motor 214 will immediately start to
rotate. After switch 75 is released, motor 214 will continue for a
predetermined interval of time, and then stops.
[0123] FIG. 10 illustrates a perspective view of a perforated
basket 168 for use with frying apparatus 100. Basket 168, provided
primarily for deep-frying foods, is preferably cylindrical in
configuration and has an upstanding inner cylindrical wall 168a
defining a central aperture, a plurality of open slots, generally
designated as 168b, for removably receiving blades 112, as shown in
FIG. 11, and a basket handle 168c for handling basket 168.
[0124] FIG. 11 illustrates a cross-sectional view of basket 168 in
an operation position. Wall 168a is installed on the central bottom
of basket 168, so as to emanate up toward the upper portion
thereof, and removably receives cylindrical wall 102b therethrough.
Slots 168b slidably receive blades 112, and whereby basket 168 is
maintained in position. Handle 168c is installed on the upper
portion of basket 168. A small recession, disposed on the upper
edge of container 102, is provided to allow the metal rods
connecting the main body of handle 168c and the main body of basket
168 to extend from inside to outside of frying apparatus 100. Wall
168a is routed over wall 102b and wall 106a is routed over both
walls 102b and 168a.
[0125] In operation, a user:
[0126] First, charges container 102 with oil, and then preheats the
oil to a predetermined temperature, preferably, halfway boiling.
This step can be one step of a cooking program.
[0127] Second, charges container 102 with the food to be fried.
[0128] Third, selects an oil temperature, a time duration, a
stirring blades rotation speed, and a blowing motor speed, or a
program for frying foods, and then pushes on start button for
activating the frying process.
[0129] The whole frying process is hand-free. The user does not
have to be involved with the frying process until the frying is
accomplished. The frying apparatus will then beep to remind the
user when the frying process is done. The fried food is, now, ready
for serving.
[0130] Reference is made to FIG. 12, which illustrates an
alternative design of frying apparatus 100 of FIG. 1, a frying
apparatus 100a. In this alternative design, a heating element
support bracket 170 is provided for supporting heating element 114.
Bracket 170 is removably supported by container support 116.
Heating element 114 is fixedly installed on bracket 170.
Temperature sensor 118 is installed on cap 130 or some other
suitable components. Container 102 is removably installed inside
container support 116, such that container 102 can be easily taken
out for food and used oil handling and for cleaning after use. When
container 102 is secured inside the opening of support 116 in an
operating position, heating element 114 and sensor 118 are in
physical contact with the bottom of container 102.
[0131] Reference is made to FIG. 13, which illustrates a
cross-sectional view of another embodiment of the present
invention, a frying apparatus 300. Some components or devices of
frying apparatus 300 are similar to those of frying apparatus 100.
Similarity is in the sense of both functionality and configuration.
Therefore, similar components or devices are denoted with similar
reference numbers for avoiding repetitive explanations. Reference
is made to frying apparatus 100 of FIG. 1 for detailed information
about these similar components or devices.
[0132] A container 302, having an open top, is provided for holding
foods and cooking oil. A central aperture is provided on the bottom
of container 302 for allowing a main shaft 304 to thread
therethrough.
[0133] A coupling device 306, having a hollow cylindrical lower
portion, is provided for coupling main shaft 304 and stirring
blades 108 for transferring rotation power. The lower portion of
coupling device 306 is fixedly engaged with blades 108. The lower
portion of coupling device 306 also has a cross-channel coupling
element 306a, or other types of coupling elements, which lockably
receives main shaft 304 via pin 122. The upper end of coupling
device 306 extends upward to substantially the open top of
container 302. In operation, the upper portion of main shaft 304
threads inside the inner opening of the lower portion of coupling
device 306. Minimal clearance is desired between main shaft 304 and
the cylindrical wall of the lower portion of coupling device 306
for ideal performance.
[0134] The lower end of shaft 304 has an inner gear 304a, as more
clearly shown in FIG. 14, for removably receiving a motor shaft
126a, which has a square or gear head, such that the lower end of
shaft 304 loosely and removably engages with motor shaft 126a. This
kind of coupling dramatically reduces the co-axial requirement on
main shaft 304 and motor shaft 126a and facilitates the assembly
process for manufacturing.
[0135] A seal assembly 308 is provided for sealing between shaft
304 and container 302, as shown in FIG. 14, which illustrates an
exploded cross-sectional view of seal assembly 308. Seal assembly
308 comprises a seal flange 310, a gland nut 312, and a compression
packing 314.
[0136] Flange 310 is co-axial to shaft 304. The first end of flange
310 is sealingly installed on the outside surface of the central
bottom of container 302. Gland nut 312 is engaged with the second
end of flange 310 by means of screw. Packing 314 creates a seal by
being squeezed between the throat of the stuffing box formed by
flange 310 and gland nut 312. The squeeze force pushes the material
against the throat of the box and rotating shaft 304.
[0137] When leakage occurs, gland nut 312 is tightened further.
This is a typical application of compression packings for low speed
rotating shafts, such as shaft 304.
[0138] Materials are extremely important when selecting the proper
packing for an application. Metallic packings are used in
high-temperature applications. Shafts for copper and aluminum
packings must be hardened to 500 Brinell hardness number (Bhn).
Copper and aluminum packings can handle 538.degree. C.
(1000.degree. F.) application temperature.
[0139] Seal assembly 308 can, alternatively, take many other forms,
such as bushing and labyrinth seals, or combinations of multiple
forms for ideal performance, as known to those skilled in the art
and suggested by this invention disclosure.
[0140] FIG. 15 illustrates an exploded cross-sectional view of an
alternative design of seal assembly 308 of FIG. 14. In this
alternative design, seal assembly 308 is installed inside container
302 on the central bottom thereof, instead of being installed
outside of container 302. The first end of flange 310 is fixedly
installed on the inner surface of the bottom of container 302 and
the second end of flange 310 extends upward to a predetermined
height above. Gland nut 312 and compression packing 314 are engaged
with the second end of flange 310.
[0141] There is an important advantage of the alternative design
illustrated by FIG. 15. For most applications, seal assembly 308 is
higher than the oil level, such that the sealing surface is not
immersed in cooking oil or hot liquid. Therefore, the requirement
on seal assembly 308 is significantly reduced. In addition, shaft
304 is much better supported at a higher level. In operation, the
lower portion of coupling device 306 is routed over seal assembly
308.
[0142] Other features of frying apparatus 300 are similar to those
of frying apparatus 100.
[0143] Reference is made to FIG. 16, which illustrates an
alternative design of frying apparatus 300 of FIG. 13, a frying
apparatus 300a. In this alternative design, a heating element
support bracket 170 is provided for supporting heating element 114.
Bracket 170 is removably supported by container support 116.
Heating element 114 is fixedly installed on bracket 170.
Temperature sensor 118 is installed on cap 130 or some other
suitable components. Container 302 is removably installed inside
container support 116, such that container 302 can be easily taken
out for food and used oil handling and for cleaning after use. When
container 302 is secured inside the opening of support 116 in an
operating position, heating element 114 and sensor 118 are in
physical contact with the bottom of container 302.
[0144] Other features of frying apparatus 300a are similar to those
of frying apparatus 300.
[0145] Reference is made to FIG. 17, which illustrates a
cross-sectional view of a further more embodiment of the present
invention, a frying apparatus 400. Some components or devices of
frying apparatus 400 are similar to those of frying apparatus 100.
Similarity is in the sense of both functionality and configuration.
Therefore, similar components or devices are denoted with similar
reference numbers for avoiding repetitive explanations. Reference
is made to frying apparatus 100 for detailed information about
these similar components or devices.
[0146] A container 402, having an open top and a closed bottom, is
provided for holding foods and cooking oil. A central shaft 404 is
provided for guiding a coupling device 406 in position. The lower
end of shaft 404 is fixedly installed on the central bottom of
container 402 and the upper end thereof extends upward toward the
open top of container 402.
[0147] Coupling device 406 is provided for operationally
transferring rotation power from a power-drive assembly 408 to
stirring blades 108. Coupling device 406 has a general
configuration of a cylindrical tube forming a central aperture
routed over shaft 404. The lower end of coupling device 406 is
engaged with blades 108 and the upper end thereof extends upward to
substantially the open top of container 402. A coupling element
406a is provided on the upper portion of coupling device 406 for
transferring rotation power.
[0148] A motor housing 410, disposed above lid 104, is pivotally
installed on the upper portion of control housing 138 via a hinge
412. Housing 410 maintains substantially horizontal when secured in
an operational position and can be conveniently lifted up via a
handle 414.
[0149] A drive motor 416 is installed inside housing 410. A motor
pulley 418 is fixedly engaged on the motor shaft for transferring
rotation power from motor 416 to a main shaft 420 via a belt 422
and a drive pulley 424. Main shaft 420 is installed onto housing
410 via a plurality of bearing elements, generally designated as
426. The lower end of shaft 420 extends downward through the floor
of housing 410. A coupling element 428, fixedly engaged on the
lower portion of shaft 420 outside housing 410, is provided for
driving an intermediate coupling device 430, which is installed on
lid 104.
[0150] Coupling device 430 includes an intermediate shaft 432, an
upper coupling element 434, and a lower coupling element 436.
[0151] The upper end of shaft 432 is fixedly engaged with coupling
element 434, which is removably coupled with coupling element 428.
Coupling element 434 can be specially designed, such that couple
element 434 also serves as a lid handle. The lower end of shaft 432
extends downward through a central aperture on lid 104 and is
fixedly engaged with coupling element 436, which is removably
coupled with coupling element 406a.
[0152] Intermediate coupling device 430 is rotatably installed on
lid 104 via a bearing element 438.
[0153] Other features of frying apparatus 400 are similar to those
of frying apparatus 100.
[0154] Reference is made to FIG. 18, which illustrates an
alternative design of frying apparatus 400 of FIG. 17, a frying
apparatus 400a. In this alternative design, a heating element
support bracket 170 is provided for supporting heating element 114.
Bracket 170 is removably supported by container support 116.
Heating element 114 is fixedly installed on bracket 170.
Temperature sensor 118 is installed on container support 116, or
some other suitable components. Container 402 is removably
installed inside container support 116, such that container 402 can
be easily taken out for food and used oil handling and for cleaning
after use. When container 402 is secured inside the opening of
support 116 in an operating position, heating element 114 and
sensor 118 are in physical contact with the bottom of container
402.
[0155] Other features of frying apparatus 400a are similar to those
of frying apparatus 400.
[0156] For all the embodiments discussed above, when the container
is large, the stirring device is consequently big, such that it may
not be quite convenient to use or handle. In order to solve this
problem, for the frying apparatus having a large container, the
lower portion of the container can be adapted to taper inward, such
that the bottom of the container has a smaller diameter.
Consequently, the stirring device can be designed smaller.
[0157] Accordingly, readers will see that this frying apparatus of
the present invention can be used to prepare tasteful fried foods
for both deep and shallow frying. The frying process is fully
automatic, thereby minimizing human involvement and chore of the
frying process. This frying apparatus is used with the lid fully
covering on top of the container, thereby eliminating the
possibility of grease splattering and the risk of oil burns to
people. At the same time, the grease-laden air generated during the
frying process is forced out through a venting device and filtered
before being discharged into the room, thereby avoiding long-term
hazards to the people and home environment.
[0158] The stirring blades sweep across food pieces intermittently,
such that the blades dwell for a predetermined dwell period
starting near the end of each stirring cycle. This intermittent
operation favors better agitation of food pieces and affords relief
from constant stirring at a higher speed.
[0159] The present invention has been described in an illustrative
manner. It is to be understood that the terminology, which has been
used, is intended to be in the nature of words of description
rather than of limitation.
[0160] Although this invention has been described in its preferred
forms and structures with a certain degree of particularity, these
should not be construed as limiting the scope of the invention but
as merely providing illustrations of some of the presently
preferred embodiments of this invention.
[0161] For examples, although this invention has been described in
a form of home frying apparatuses, it can have potential business
use, such as use in restaurants. Therefore, this invention can
alternatively be described as food processing equipment. Although
the forced venting system of this invention has been described in a
form of blowing fresh air into the frying apparatus, it is
understood that rearrangement of the motor, fan, and filters, such
that, instead of blowing fresh air into the frying apparatus, the
fan actually draws the moisture-laden and grease-laden air out of
the frying apparatus, is perfectly inline with the spirit of the
forced venting concept of this invention. Such rearrangement is,
therefore, covered by the present invention.
[0162] Thus it is understood that the present disclosure of the
preferred forms can be changed in the details of construction and
in the combination and arrangement of parts without departing from
the spirit and the scope of the invention as hereinafter
claimed.
* * * * *