U.S. patent application number 09/954836 was filed with the patent office on 2002-04-04 for fryer.
This patent application is currently assigned to PALOMA INDUSTRIES, LIMITED. Invention is credited to Chikazawa, Hideo, Hayakawa, Tsuneyasu, Kijimoto, Hideki.
Application Number | 20020038604 09/954836 |
Document ID | / |
Family ID | 18767685 |
Filed Date | 2002-04-04 |
United States Patent
Application |
20020038604 |
Kind Code |
A1 |
Chikazawa, Hideo ; et
al. |
April 4, 2002 |
Fryer
Abstract
The invention provides a fryer that can prevent problems such as
poorly cooked food when operation of an oil discharge valve is
started and cooking oil is discharged, for example, to adjust the
liquid level of the cooking oil within an oil vat. The fryer
includes oil vats 13 and 14 for containing cooking oil, a burning
device 17 for heating the cooking oil within the oil vats, an oil
discharge pipe 33 that extends from the bottom of the oil vat and
that discharges the cooking oil from a discharge opening at its end
into a tank, and an oil discharge valve 35 that is disposed in the
oil discharge pipe and that opens and closes the oil discharge
pipe. Furthermore, the fryer is provided with a micro switch 47 and
a contact piece 48 for detecting the open state of the oil
discharge valve, and alarms 55 and 56 for giving a warning in
accordance with the results of the detection by the micro switch 47
regarding the open state of the oil discharge valve. When the micro
switch 47 detects that the oil discharge valve has continuously
remained in an open state and a predetermined time has passed,
heating by the burning device 17 is stopped by controls from
control devices 60A and 60B.
Inventors: |
Chikazawa, Hideo;
(Nagoya-shi, JP) ; Hayakawa, Tsuneyasu;
(Nagoya-shi, JP) ; Kijimoto, Hideki; (Nagoya-shi,
JP) |
Correspondence
Address: |
PEARSON & PEARSON
10 George Street
Lowell
MA
01852
US
|
Assignee: |
PALOMA INDUSTRIES, LIMITED
|
Family ID: |
18767685 |
Appl. No.: |
09/954836 |
Filed: |
September 18, 2001 |
Current U.S.
Class: |
99/330 ; 99/403;
99/407; 99/408 |
Current CPC
Class: |
A47J 37/1285
20130101 |
Class at
Publication: |
99/330 ; 99/403;
99/407; 99/408 |
International
Class: |
A47J 037/12; A23L
001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 19, 2000 |
JP |
2000-283301 |
Claims
What is claimed is:
1. A fryer comprising: an oil vat for containing cooking oil; a
burning device for heating the cooking oil within the oil vat; an
oil discharge pipe that extends from the bottom of the oil vat and
that discharges the cooking oil from a discharge opening at its end
into a tank; an oil discharge valve that is disposed in the oil
discharge pipe and that opens and closes the oil discharge pipe; an
open valve detection means for detecting an open state of the oil
discharge valve; a warning means for giving a warning according to
a detected result of an open state of the oil discharge valve by
the open valve detection means; a combustion stopping control means
for controlling the burning device so that it stops combustion when
a period of time that the open valve detection means has
continuously detected that the oil discharge valve is open reaches
a predetermined time.
2. The fryer according to claim 1, wherein a time lag is provided
between when the oil discharge valve is first opened and when the
cooking oil begins to be discharged from the oil discharge pipe,
and wherein the warning means gives a warning immediately after the
oil discharge valve starts to open.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a fryer in which an oil
discharge pipe is opened and closed to discharge cooking oil in an
oil vat by opening and closing an oil discharge valve that is
disposed in the oil discharge pipe, which extends from the bottom
of the oil vat.
[0003] 2. Description of Related Art
[0004] Conventionally, in fryers of this type, some cooking oil is
removed together with the foods after cooking the foods, so in
order to supplement lost cooking oil, the oil vats are periodically
replenished with cooking oil. For the cooking oil, when oil such as
lard, which is a solid oil at normal temperature, is replenished,
although it remains solid immediately after being added, the lard
gradually melts, and when it has liquefied its volume increases,
resulting in an increase of the liquid level in the oil vat and
frequently causing the liquid level to exceed the prescribed liquid
level. By the liquid level of the cooking oil in the oil vat
fluctuating between above and below a certain range of the
prescribed liquid levels, the heating conditions of the foods
change, and the result is a disparity in cooked foods, which is
undesirable. Consequently, to counter such over-replenishing of
cooking oil, it is necessary to open an oil discharge valve and
discharge excess cooking oil from an oil discharge pipe into an oil
tank in order to maintain the liquid level of the cooking oil at
the prescribed liquid level.
[0005] However, by opening the oil discharge valve, too much
cooking oil may be discharged, or if the oil discharge valve is
mistakenly left in a state in which it is incompletely closed, the
cooking oil can fall below the prescribed liquid level, the heating
temperature of the foods by the cooking oil become too high, and
the cooked foods result in being uneven, which is undesirable.
Furthermore, there is also the possibility that an accident, such
as the cooking oil catching fire, could occur by abnormally
over-heating the cooking oil. Moreover, in the case of when
cleaning the inside of the oil vats, there is the possibility of an
accident caused by abnormal-overheating of the cooking oil when the
opening/closing valve is opened in order to release the cooking oil
from the oil vat and when the oil vats are mistakenly heated.
[0006] For that reason, among conventional fryers, there are those
that stopped heating of the oil at the same time that the oil
discharge valve is opened. With these fryers, however, each time
the oil discharge valve is opened during cooking, the foods become
poorly cooked because of inadequate heating, and it is necessary to
discard these poorly cooked foods, resulting in an extreme waste of
foods. On the other hand, in other fryers, a warning goes off the
moment the oil discharge valve is opened. However, even if a
warning is sounded, if the cook cannot take quick measures in
response to the warning such as closing the oil discharge valve or
stopping the combustion of the fryer because the cook is too busy
or absent, there is the problem that inconveniences caused in
conjunction with the reduction in cooking oil in the oil vat could
not be properly addressed.
[0007] The present invention solves the aforementioned problems,
and an object of the present invention is to provide a fryer that
can prevent inconvenience such as the poor cooking of foods when an
oil discharge valve operation is initiated and the cooking oil is
discharged, for example, to adjust the liquid level of the cooking
oil within the oil vat.
SUMMARY OF THE INVENTION
[0008] To achieve the above-mentioned object, in accordance with a
first aspect of the present invention, a fryer includes an oil vat
for containing cooking oil, a burning device for heating the
cooking oil in the oil vat, an oil discharge pipe that extends from
the bottom of the oil vat and that discharges the cooking oil from
a discharge opening at its end into a tank, and an oil discharge
valve disposed in the oil discharge pipe and is for opening and
closing the oil discharge pipe, wherein the fryer is provided with
an open valve detection means for detecting an open state of the
oil discharge valve, a warning means for giving a warning according
to a dictated result of an open state of the oil discharge valve by
the open valve detection means, and a combustion stopping control
means for controlling the burning device so that it stops
combustion when a period of time that the open valve detection
means has continuously detected that the oil discharge valve is
open reaches a predetermined time. Here, the predetermined time
means the time lag giving the fryer safety that heating an empty
oil vat such as the cooking oil catching fire will not occur even
if the cooking oil is discharged in a state wherein the oil
discharge valve is completely open.
[0009] With this configuration according to the first aspect of the
invention, to counter, for example, the over-replenishing of
cooking oil, when the oil discharge valve is opened and excess
cooking oil is discharged from the oil discharge pipe into the tank
in order to maintain the liquid level of the cooking oil at the
prescribed liquid level, the open valve detection means detects
that the oil discharge valve is in an open state, and in response,
the warning means gives a warning that the oil discharge valve is
in an open state. Thus, even after the oil discharge valve has been
operated, without interrupting preparation for food, it is possible
to clearly identify from the warning that the oil discharge pipe is
open and that the cooking oil in the oil vat is being
discharged.
[0010] Furthermore, when the oil discharge valve continuously
remains open for a predetermined time, combustion by the burning
device is automatically stopped with controls from the combustion
stopping control means. That is, the burning device is stopped
after a prescribed time has passed, wherein the prescribed time is
the time lag giving the fryer safety before heating an empty oil
vat such as the cooking oil catching fire occurs, and thus heating
an empty oil vat can be prevented before it happens.
[0011] Moreover, with the configuration according to a second
aspect of the invention, in a fryer according to the first aspect
of the invention, a time lag is provided between when the oil
discharge valve is first opened and when cooking oil begins to be
discharged from the oil discharge pipe, and wherein the warning
means gives a warning immediately after the oil discharge valve
starts to open. Therefore, an operator can quickly be aware that
the oil discharge valve is open, and there is leeway before the oil
discharge valve is closed. In particular, the discharge of the
cooking oil can be minimized in the event that the oil discharge
valve is accidentally opened.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a lateral view showing the schematic configuration
of one embodiment of the fryer of the present invention.
[0013] FIG. 2 is a front view showing the schematic configuration
of the fryer in FIG. 1.
[0014] FIG. 3 is a lateral view showing the oil supply and
discharge mechanism, which is a primary element of the fryer in
FIG. 1.
[0015] FIG. 4 is a lateral view showing the valve opening/closing
device.
[0016] FIG. 5 is a planar view showing the valve opening/closing
device of FIG. 4.
[0017] FIG. 6 is a lateral view showing the open/close detection
portion of the oil discharge valve.
[0018] FIG. 7 is a flow chart of the "oil discharge control
program" executed by the control device.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] An embodiment of the present invention is described below
with reference to the drawings. FIG. 1 and FIG. 2 show a lateral
view (excluding the right side panel) and a front view (excluding
the front side plate) of a schematic configuration of a fryer for
commercial use in this embodiment. FIG. 3 shows a lateral view of
the cooking oil supply and discharge mechanism, which is an
essential part of the fryer.
[0020] The fryer is provided with a box-shaped housing 10, and
stands on a floor F, supported by casters 12 provided at the four
corners of a bottom panel portion 11a of the housing 10. A pair of
left and right oil vats 13 and 14 for containing cooking oil is
provided in the upper portion of the housing 10, with the oil vat
13 on the left side being a split vat divided into two parts, and
the oil vat 14 on the right side being a single full vat. The full
vat has one oil supply pipe and one oil discharge pipe, and the
split vat has two oil supply pipes and two oil discharge pipes.
[0021] Apron portions 13a and 14a, which are frame-shaped and have
a front portion projecting forward, are integrally attached to the
upper edge of the oil vats 13 and 14. A vertical panel 15 extending
upward is provided on the rear wall of the apron portions 13a and
14a. A pair of air chambers 16 is attached to the front of the oil
vats 13 and 14. A burning device 17 for heating the cooking oil in
the oil vats is disposed on a side portion of the oil vats 13 and
14 (only the one corresponding to the oil vat 14 is shown). The
burning device 17 is provided with a combustion chamber 17a fixed
to the inner surface of a sidewall of the oil vat 14, and a pipe
17b disposed in a looping fashion within the oil vat 14 with one
end fixed to the exit of the combustion chamber 17a and the other
end passing through a sidewall of the air chamber 16, and serving
as a conduit to the outside. The pipe 17b is in communication with
an extension pipe portion 17c, which is fixed to a sidewall of the
air chamber 16.
[0022] Each air chamber 16 is connected to a gas supply pipe 21,
which is provided with an electromagnetic valve 22, and also
connected, via an air supply pipe 25, with an electrically driven
fan 23 and an air supply muffler 24. Additionally, the burning
devices 17 are each provided with a silencing device 26. The
silencing devices 26 are provided with a lower exhaust muffler 27
disposed on the lower side of the rear portion of the oil vats 13
and 14, and an upper exhaust muffler 28 disposed on the upper side
of the rear portion of the oil vats 13 and 14. The exhaust mufflers
are connected in series, and a release pipe 29 for releasing
exhaust into the air is attached to the upper end of the upper
exhaust muffler 28. An oil tank 31 is placed on the bottom panel
portion 11a in the housing 10, and an oil pump 32 is provided at
the rear portion of the oil tank 31.
[0023] As shown in FIG. 3, the supply and discharge mechanism is
provided with a pair of oil discharge pipes 33 projecting from the
oil vats 13 and 14, and an oil discharge collection potion 34 is
attached to the end of the oil discharge pipes 33, so that oil is
discharged from a discharge opening 34a of the oil discharge
collection 34 into the oil tank 31 underneath. An oil discharge
valve 35 of a ball valve type is attached adjacent to the oil
discharge collection portion 34 of the oil discharge pipe 33 for
opening and closing the oil discharge pipe 33 according to the
rotating position of the ball. A pair of symmetrical left and right
valve opening/closing devices 40 are disposed on the oil discharge
valve 35.
[0024] As shown in FIG. 4 and FIG. 5, the valve opening/closing
device 40 is configured with a long bar-shaped fixed link portion
41, wherein one end is fixed to a protruding portion 36 of the
valve at a rotating shaft 37 of the oil discharge valve 35, and
wherein the fixed link portion 41 is substantially perpendicular
with respect to the rotating shaft 37 and extends in the direction
of the oil discharge collection portion 34; a first rotating link
portion 42 of short bar-shape fixed at one end to the rotating
shaft 37; a second rotating link portion 43 of a length
substantially equal to that of the first rotating link portion 42,
and which at one end is rotatably attached to the other end of the
fixed link portion 41; a long bar-shaped coupling link portion 44
of a length substantially equal to the fixed link portion 41,
wherein both ends are rotatably fixed to the other ends of the
first and second rotating link portions 42 and 43; and a rotating
lever portion 45 integrally fixed to the other end of the second
rotating link portion 43, wherein the rotating lever 45 is disposed
on the same surface as the second rotating link portion 43 and
extends and tilts at substantially 30.degree. forward with respect
to the second rotating link portion 43.
[0025] When the oil discharge valve 35 is closed, the first and
second rotating link portions 42 and 43 are tilted at a 30.degree.
angle to the rear with respect to a sideways orientation, and when
the oil discharge valve 35 is open, the first and second rotating
link portions 42 and 43 are tilted 60.degree. forward with respect
to a sideways orientation. Thus, when opening or closing the oil
discharge valve 35, by rotating the rotating lever 45 for
90.degree., the oil discharge valve 35 can be easily closed in the
same way. The result is that even women or elderly people, who have
little strength, can easily perform the opening and closing
operation of the oil discharge valve 35. Moreover, the position of
the rotating lever 45 corresponding to the open state and closed
state of the oil discharge valve 35 is regulated so that the
rotating lever 45 is orientated sideways or frontward when viewed
from the front surface, so that by looking at the position of the
rotating lever 45 it is possible to ascertain with one glance
whether the oil discharge valve 35 is in an open state or a closed
state, and thus is extremely convenient.
[0026] As shown in FIG. 6, an attaching plate 46 of a rectangular
shape is fixed at one end side to an intermediate position of the
longitudinal direction of the fixed link portion 41, and extends in
the direction of the coupling link portion 44. A micro switch 47,
of a type wherein movement of a movable piece pushes a contact
point to activate the switch, is fixed to the other end of the
attached plate 46. A contact piece 48 is fixed to an intermediate
position of the longitudinal direction of the coupling link portion
44, and when the contact piece 48 comes into contact with the
movable piece of the micro switch 47, it shifts that movable piece.
The micro switch 47 and the contact piece 48 constitute a valve
open/close detection means. In addition to the combination of the
micro switch and the contact piece, a proximity switch that uses a
reed switch, for example, can also be used. When the oil discharge
valve 35 is opened by rotating the rotating lever 45, the contact
piece 48 disposed on the coupling link portion 44 immediately
pushes the movable piece of the micro switch 47 to come into
contact with the contact point, thus turning the switch on. Here,
the oil discharge valve 35 is of a ball valve type, and has a
difference of roughly 5.degree. in the rotating angle between when
the rotating shaft 37 begins to rotate and when the pipe pathway
opens. For that reason, even if alarms 55 and 56, which are
explained later, start to sound by the oil discharge valve 35
starting to be opened, cooking oil is not immediately discharged
from the oil vats 13 and 14, and by further rotation of several
degrees after the alarm has sounded the oil is released.
[0027] The oil supply pipe 38 projects from the bottom of the oil
tank 31, and is connected to the oil vats 13 and 14 via the oil
pump 32. An oil supply valve 39 of a ball valve type is disposed in
the oil supply pipe 38 on the downstream side of the oil pump 32. A
valve opening/closing mechanism 50 is disposed on the oil supply
valve 39. The valve opening/closing mechanism 50 is provided with a
rotating link portion 51 of a short bar-shape that is fixed at one
end to a rotating shaft 39a of the oil supply valve 39, a coupling
link portion 52 of a long bar-shape that is rotatably attached to
the other end of the rotating link portion 51, extends
substantially horizontally until the front side of the housing 10,
and is bent at a plurality of positions, and a lever portion 53
that is in the shape of the letter v, wherein the corner thereof is
rotatably supported by the housing, and wherein one end is
rotatably attached to the coupling link portion 52. The valve
opening/closing mechanism 50, by the rotation operation of the
lever portion 53, easily opens and closes the oil supply valve
39.
[0028] Alarms 55 and 56, which are warning means associated with
the oil vats 13 and 14, are attached to the bottom left and right
sides of the air chamber 16 on the front side of the housing 10.
For the warning means, instead of an audible warning such as an
alarm or a voiced message, it is also possible to execute a visual
warning by using an illuminant, such as a lamp, or a display, such
as a picture display device, or a combination thereof.
[0029] Control devices 60A and 60B, for electrically controlling
the operation of the aforementioned supply and discharge mechanism,
are disposed on both the left and right sides on the bottom panel
portion 11a of the housing 10, and control the operation of the
supply and discharge mechanism corresponding to the left and right
oil vats 13 and 14, respectively. Below is an explanation of the
control device 60B corresponding to the right oil vat 14. The
control device 60B includes a microcomputer that is made up of a
ROM, a CPU, a RAM, a counter, and an I/O device, for example, and
that executes the "oil discharge control program" shown in FIG. 7.
The micro switch 47 is connected to the input side of the control
device 60B, and the alarms 55 and 56, the oil supply pump 32, and
the electromagnetic valve 22 of the burning device 17, for example,
are connected to the output side of the control device 60B.
[0030] Next is an explanation of the operation of the embodiment
with this configuration.
[0031] By turning on a power switch, which is not shown in the
drawings, the control device 60B starts executing the "oil
discharge control program" at step 70, initializes the various
control variables, and then determines whether combustion by the
burning device 17 has begun or not (steps 71 and 72). If the
combustion has already begun, the program determines whether the
oil discharge valve 35 is open or not (step 73). When the oil level
in the oil vats 13 or 14 is below the prescribed liquid level due
to cooking, solid lard is added. At first the liquid level of the
oil is at the prescribed liquid level when lard is added, but when
the lard melts, the oil level may become higher than the prescribed
liquid level. In such a case, by operating the valve
opening/closing device 40, the oil discharge valve 35 is opened in
order to lower the liquid level.
[0032] This operation turns on the micro switch 47, in response to
that, the control device 60B starts sounding the alarm 56 and at
the same time resets a timer and begins to measure time for a
prescribed time of five seconds (steps 73 through 75). If the valve
opening/closing device 40 is operated and the oil discharge valve
is closed within the five seconds, the control device, based on the
decisions of "NO" at step 76 and "YES" at step 77, returns the
program to step 73 and executes the steps below in a similar
fashion. Then, if the prescribed time of five seconds has passed
with the alarm 56 still sounding, that is, with the oil discharge
valve 35 being open, the combustion operation of the burning device
17 is stopped (step 78), and the controls for the control device
60A are ended (step 79).
[0033] As described above, according to the present embodiment, in
accordance with the oil discharge valve 35 being open, the alarm 56
gives a warning that the oil discharge valve 35 is in an open
state, and thus after the oil discharge valve 35 has been opened,
the warning makes it possible to clearly ascertain that the oil
discharge pipe 33 is open and that the cooking oil in the oil vat
14 is being discharged. In particular, should the oil discharge
valve 35 be accidentally opened, it is possible to be immediately
aware that the oil discharge valve 35 is open, which is convenient.
Additionally, foods are not wasted because cooking is not
interrupted. Furthermore, when the duration of open the oil
discharge valve 35 reaches the prescribed time of five seconds, the
combustion by the burning device 17 is automatically stopped, and
thus accidents such as the cooking oil catching fire caused by
heating the empty oil vats, can be prevented before they occur.
[0034] Moreover, as the oil discharge valve 35 is of a ball valve
type, and there is a roughly 5.degree. difference in the rotating
angle between when the rotating shaft 37 starts rotating and when
the pipe pathway is opened, even if the alarm 55 and 56 start to
sound, by beginning to open the oil discharge valve 35 the cooking
oil is not immediately discharged from the oil vats 13 and 14, and
there is a slight delay before the cooking oil is discharged.
Consequently, an operator can quickly be aware that the oil
discharge valve 35 is open, there is still enough time to close the
oil discharge valve 35, and in particular, the discharge of the
cooking oil can be minimized in the event that the oil discharge
valve 35 is accidentally opened.
[0035] According to the first aspect of the invention, after the
oil discharge valve is operated, it can be clearly ascertained from
the warning that the oil discharge pipe is open and that cooking
oil in the oil vats is being discharged, without interrupting
preparation for food. In particular, if the oil discharge valve is
accidentally opened, an operator can be immediately aware that it
is open, which is convenient. Furthermore, when the prescribed time
of five seconds of the oil discharge valve being constantly open
has passed, the combustion by the burning device is automatically
stopped, and thus accidents such as the cooking oil catching fire
caused by heating the empty oil vats, can be prevented before they
occur.
[0036] Moreover, a time lag is provided between when the oil
discharge valve is opened and when the cooking oil begins to be
discharged from the oil discharge pipe, and immediately after the
oil discharge valve starts to open, a warning means gives a warning
that makes it possible to quickly inform that the oil discharge
valve is open and to have time left to close the oil discharge
valve. In particular, the discharge of the cooking oil can be
minimized in the event that the oil discharge valve is accidentally
opened (effect of the second aspect of the invention).
[0037] The invention may be embodied in other specific forms
without departing from the spirit or essential characteristics
thereof. The embodiments disclosed in this application are to be
considered in all respects as illustrative and not restrictive, the
scope of the invention being indicated by the appended claims
rather than by the foregoing description. All changes that come
within the meaning and range of equivalency of the claims are
intended to be embraced therein.
* * * * *