Note: Descriptions are shown in the official language in which they were submitted.
1:~7~765
BACKGROUND OF THE INVENTION
This invention relates to food processors, and
more particularly to a protective interlock for such machines
in which an actuator member must be inserted into a keyway
configured slot in order to enable the operation of the
food processor, for protecting the user as well as the
Imachine from accidental actuation when the components of the
food processor are not properly in place.
Food processors of the type in which the present
invention is applicable have a working bowl with tool mounting
means projecting upwardly in the bowl, on which various
;selected rotary food processing tools can be mounted to be
driven for performing various food processing operations
in accordance with the desires of the user. A removable
cover is secured over the top of the bowl during use. The
cover includes a feed tube or food receiving hopper having
,~a mouth that opens downwardly through the cover into the
top of the bowl. The food items to be processed are placed
in this feed tube and are then manually pushed down through
the feed tube into the bowl by means of a removable food
pusher which is adapted to slide down in the manner of a
plunger through the feed tube.
Such a food processor is shown and described in
IU.S. Patent No. 3,892,365 - Verdun. This patent also dis~
,closes a safety feature in providing a vertical movable rod
housed in a semicylindrical boss which e~tends vertically
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the height of the bowl and encloses the operating rod which
is aligned with and is adapted to actuate an on-off switch
for controlling the motor. The operating rod is spring-
biased upwardly to prevent depressing the motor switch unless
the detachable cover is suitably positioned on the working
bowl. A cam is mounted on the rim of the cover which is
adapted to depress the top end of the operating rod to
actuate the motor switch. This motor switch is not intended
to be actuated unless the cover is properly positioned on
the bowl.
More recently there has been commercially offered
for sale a food processor in which such a cam is mounted
upon an outer sleeve which fits down over the feed tube on
the cover. Thus, the operating rod is not actuated unless
the cover is properly positioned on the bowl and the outer
sleeve is also fitted down over the feed tube.
SUM~RY
Accordingly, it is an object of the present
invention to provide a new and improved food processor which
prevents operation of the food processor by the user unless
the actuator on the cover or an outer sleeve carrying the
actuator is properly in pla~e.
Another object of this invention is to provide
a new and improved food processor having a safety actuation
means which is covered with access available only through
a keyway configured opening and therefore must be manually
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operated by the user in an appropriately safe manner to
enable operation of the food processor and thereby prevent
inadvertent injury either to the user or to the food proc-
essor.
In carrying out this invention in one illustrative
embodiment thereof, there is a food processor of the type
including tool drive means which is driven by a motor drive
in a base having control means for rendering the motor
drive inoperative unless the control means is actuated.
A bowl is mounted on the base for enclosing a rotary tool
within the bowl, and a movable operating rod is associated
with the bowl for actuating the control means when this rod
is depressed. The rotatable tool is driveable by the tool
drive means. A removable cover for the bowl has a food
receiving hopper or feed tube extending through the cover
into contact with the rotating tool in the bowl, and a food
pusher is insertable into this feed tube for pushing food
items downwardly in the feed tube towards the rotating tool.
An actuator is positioned on the cover, and a semicylindrical
boss on the bowl forms a guideway in which said movable
operating rod is housed in alignment with the control means.
The boss has a keyway configured slotted cap covering the
upper end of the operating rod, thereby preventing access
to the rod to prevent accidental actuation of the control
means when the components of the food processor are not
~properly positioned. The actuator means has a surface with a
keyway therein which fits into and is capable of passing
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through the configured slot in the cap for depressing the
movable rod for actuating the control means.
The actuator means may be advantageously integrally
mounted on the cover or may be a part of an outer sleeve
which fits down over the feed tube in nesting relationship
thereon.
Among the advantages provided by the present
covered safety interlock are those resulting from the fact
that the slot in the cap which lead to the operating rod
permits access to the upper end of this rod only through
a keyway configured opening, thereby protecting the rod
from inadvertent actuation through the top of the boss, and
this structure makes it difficult to otherwise actuate the
rod without utilizing the actuator having a complementary
keyway therein which perfectly fits into the slotted cap.
As a result, it is extremely difficult to accidentally or
inadvertently actuate the operating rod for energizing the
tool drive unless the key actuator is in inserted position
in the slotted cap on the boss on the bowl which encloses
the operating rod.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention, together with further objects,
features, aspects and advantages thereof, will be more
clearly understood from a consideration of the following
description taken in conjunction with the accompanying
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drawings in which the same reference numbers are used to
refer to corresponding elements throughout the various
~views.
FIG. 1 is a front perspective view of a food
processor embodying the present invention in which the
actuator is an integral part of the cover. This view is
seen from in front and above the food processor.
FIG. 2 is an enlarged front view of the covered
safety interlock embodying the present invention, in which
the actuator is mounted on an outer sleeve positioned on
the cover of the food processor over the feed tube thereon.
FIG. 3 is a cross-sectional view taken along
line 3-3 of FIG. 2.
FIG. 4 is a cross-sectional view taken along
line 4-4 of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to FIG. 1, a food processor,
referred to generally with the reference character 10, is
illustrated having a base housing 12 with a working bowl
18 mounted thereon. The top of the bowl 18 is closed by a
~cover 20 which is arranged to be engaged in fastened or
~secured relationship in its normal operating position on the
bowl 18, whenever the food processor 10 is in operation.
IExtending upwardly from the cover 20 is a food receiving
hopper or feed tube 30 which opens downwardly through the
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cover 20. The feed tube 30 is designed to receive a food
pusher 32 which is manually insertable in the manner of a
plunger and is employed to push food items down into engage-
ment with a rotating tool (not shown) mounted on tool
mounting means (not shown) for rotation in the bowl 18.
As is more fully shown and described in the
aforesaid Verdun patent, the housing 12 contains a relatively '
~powerful electric motor for driving tool mounting means
which extends upwardly from the housing 12 into the working
"bowl 18. A variety of different types of food processing
tools are provided which may be selectively mounted on the
;tool mounting means for rotation within the bowl 18. Since
the tool and the tool drive apparatus form no part of the
present invention, and are conventional, one example of
which is illustrated in said Verdun patent, they are not
shown nor described in detail here. Also, the Verdun patent
shows one method of obtaining a securing engagement of the
cover on the bowl in the form of rim mounted depending lugs
~which upon rotation of the cover engage beneath a plurality
~of radial ledges on the lip of the bowl 18. Likewise, other
suitable means may be used to secure or fasten the cover in
place on the bowl such as are now being used on the various
commercially available food processors.
As will be seen in FIGS. 1 and 2, a vertical
semicylindrical boss 22 is formed on the outside of the
wall of the bowl 18. This boss 22 defines a guideway in
which is carried a vertically movable operating rod 24.
This rod 24 is normally urged upwardly by means of a spring
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26. As will be seen in FIG. 2, when the bowl 18 is
properly positioned on the housing 12, the operating rod 24
is aligned with an actuating button 16 of tool drive control
means 14, for example such as a motor switch. There is
a flexible liquid-tight membrane 28 in the base housing 12
above the control means 14 for protecting the interior of
this housing from entry of liquids or food particles.
Either the cover 20 as illustrated in FIG. 1 or
an outer sleeve 35 which is positioned on the cover and
fits over the feed tube 30 in nesting relationship th~reon
(see FIG. 2) carries an annular flange 34 along one side
thereof which is at a lower elevation than the lower end
of the cover or of the outer sleeve. This flange 34 is
provided with additional support by upwardly extending
stiffening ribs 36. This annular flange 34 carries a
downwardly extending cam 38 which is adapted, when the
cover 20 is positioned properly on the bowl and is rotated,
to contact and to depress the vertically movable operating
rod 24 to actuate the motor of the food processor 10 for
rotating the tool in the bowl.
It is to be noted that this particular structure
with the actuator in the form of an annular flange and with
a cam extending from the cover is shown in the aforesaid
Verdun patent. When such a cam is mounted on an outer
sleeve which fits over the feed tube, one such form of
structure is shown and described in Canadian Patent No.
1,13g,193 issued January 11, 1983, which is assigned to the
assignee of the present invention.
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The present invention departs from these aforesaid
structures in providing a protective cover which encloses
the upper end 25 of the vertically movable operating rod
24 for protecting it from accidental or unauthorized
operation. In the ~erdun patent and in said patent appli-
~cation, the top of the boss 22 was open so that the upperend 25 of the operating rod 24 was exposed, and thus
iinadvertent or accidental actuationof the operating rod
might occur.
In order to protect the upper end 25 of the
~operating rod 24 and to make it difficult to inadvertently
or accidentally actuate this operating rod, a keyway slotted
protector cap 42 is mounted on the top of the boss 22
surrounding this upper end 25. As is best seen in FIGS.
3 and 4, the slotted protector cap 42 has a narrow top
slot 44 therethrough and has apair of opposed aligned side
wall slots 46 which extend completely through the cap. The
top slot 44 is preferably slightly curved and is correspond-
ing in curvature to the curvature of therim of the cover 20.
In other words, the top slot 44 preferably has a curvature
lwhich is concentric aboutthe central axis of the working
bowl and its cover. This top slot 44 is considerably
narrower than the side wall slots 46.
Thus, advantageously, the narrow top slot 44 in
cooperation with the enlarged side wall slots 46 define a
specially configured access opening in the nature of a
keyway slot, such that inadvertent or accidental access to
the top end 25 of the actuator rod 24 is prevented, and
access thereto can only be obtained by acam member having a
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¦Icomplementary keyway shaped configuration. Consequently,
lithe mocor drive unit in the food processor base housing 12
¦~cannot readily be actuated, except with a cam having an
lappropriate keyway shaped configuration~
As will best be seen in cross section in FIG. 4,
the downwardly projecting cam 38 extending down from the
~annular flange 34 has a groove or keyway 40 in its side
~^ surface thereby forming a thin web portion 47 of the cam
¦which accurately fits into the narrow top slot 44 in the
iprotector cap 42. Also, the enlarged lower portion 49
iof the cam 38 accurately fits into the enlarged side wall
¦slots 46 which are located in the side walls of the protector
cap 42. The lower edge of the cam 38 is inclined as seen
lin FIG. 2 for pro~iding a cam surface 50 to provide a positive
means for depressing the push rod 24 when the narrow web
47 and the enlarged lower portion 49 of the cam 38 are
inserted (as seen in FIGS. 2, 3 and 4) into the keyway
configured top slot 44 and side wall slots 46.
The narrow web 47 preferably has a curvature
(as seen in horizontal section in FIG. 3~ corresponding
with the curvature of the top slot 44. In other words,
~the narrow web 47 is concentric about the central axis of
~the bowl and cover. Therefore, when the cover 20 is placed
¦¦upon the bowl 18 and is rotated into its normal operating
¦~position on the bowl, the keyway configured cam 38, 40, 47,
49, 50 readily enters into the corresponding keyway configured
l access slots 44, 46 in the protector cap 42. It is intended
i that there be sufficient tolerance in the slot 44, 46 as
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~well as in the configuration of the keyway cam 38, 40, 47,
49, 50 for providing easy entry by rotating the cover into
~operative position for depressing the actuating rod 24 for
operating the food processor.
As discussed above, the keyway configured cam
38, 40, 47, 49, 50 may be mounted on the cover 20 as shown
~in FIG. 1 or it may be mounted on an outer sleeve 35 (FIG.
2) which can be slipped down over the feed tube 30 on the
cover to position the cam in operative position relative
to the cover and to the protector cap 42 for actuating the
food processor. The actuator rod protection safety features
provided by the present invention are the same in both
embodiments. That is, the protection of the actuator
rod is the same regardless of whether the keyway configured
cam is mounted directly on the cover or is mounted directly
in an outer sleeve which in turn can be slid down in
;telescoping relationship around the feed tube on the cover.
Therefore, the term "actuator means associated with the
cover" is intended to be interpreted sufficiently broadly
to include a food processor in which the actuator means
,is mounted directly on the cover itself and also to include
a food processor in which the actuator means is mounted on
an attachment (such as an outer sleeve 35 which fits down
over the feed tube 30) which in turn fits onto the cover.
In either case, the cover must be placed on the bowl in its
normal operating position on the bowl for causing the
actuator means to actuate the control means for rendering
the motor drive operative.
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It is to be noted that the control means 14 (FIG.
2) may serve to control the energization of the electric
motor in the food processor for rendering the motor drive
operative for driving a tool in the bowl 18. Alternatively,
this control means 14 may serve to control the operation
of a clutch in the motor drive for rendering the motor
drive operative for driving a tool in the bowl 18. In
lother words, the motor itself may be turned on by a different
switch, and then a clutch must be actuated by the control
means 14 before the tool in the bowl 18 becomes driven by
the motor. Therefore, the terms "control means" and "motor
~drive" are intended to be interpreted sufficiently broadly
to include either of these control arrangements for rendering
~the motor drive operative and inoperative.
It is to be noted that in the embodiments of
this invention which have been described, the protector
cap 42 serves to protect the upper or outer end 25 of the
actuator rod 24. There are food processors in use today
in which the control means 14 is located in an elevated
position in an upstanding portion of the machine housing
112 adjacent to the bowl 18 and cover 20. Such an elevated
control means is located at a position near the rim of the
Icover so that the actuator button 16 can be directly acted
upon by the cam. In other words, in such a food processor
having the control means 14 at an elevated location, the
actuator rod 24 is omitted, and the cam 38 acts directly
lupon the actuating button 16 of the control means. In
such a food processor with an elevated control means, the
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protector cap 42 is positioned on the upstanding portion
of the base housing and has a keyway configured access
opening similar to the keyway configured opening 44, 46 as
shown in FIGS. 2, 3 and 4 so that access thereto can be
obtained only by a complementary configured cam such as
the keyway configured cam 38, 40, 47, 49, 50. In such a
food processor with an elevated control means, the keyway
configured cam can be mounted directly on the rim of the
~cover or can be mounted on an outer sleeve 35 (FIG. 2) which
Islides down over the feed tube 30.
¦; Also, it is to be understood that in lieu of
positioning the control means 14 itself at an elevated
;location in such an upstanding portion of the base housing,
the actuating button 16 can be lengthened to form an actuat-
ing rod or actuating linkage extending upwardly within an
upstanding portion of the machine housing. Then, the
iouter or upper end of this actuating rod is at an elevated
location, while the control means 14 itself is at a lower
elevation in the base housing 12. Then, the protector
cap 42 is arranged to protect the upper or outer end of
this actuating rod or linkage.
In summary, in all of the various embodiments of
this invention which have been described, the protector
cap 42 with its keyway configured access opening encloses
and protects the upper or outer end of the actuating element
'which is to be acted upon by the complementary shaped cam,
thereby protecting the actuating element from inadvertent
or accidental actuation.
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As shown in FIG. 3, the cover 20 may include
a skirt which snuggly fits down within the top of the
Ibowl 18 or which overlaps the top of the bowl for fitting
;down snuggly outside of the bowl 18.
Since other changes and modifications varied to
llfit particular operating requirements and environments will
be apparent to those skilled in the art, .the invention is
not considered limited to the examples chosen for purposes
¦of illustration, and includes all changes and modifications
which do not constitute a departure from the true spirit
and scope of this invention as defined by the following
claims and equivalents thereof.
What is claimed is:
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