Note: Descriptions are shown in the official language in which they were submitted.
~1~55~
The invention concerns a power unit driven b~ an
electric motor, adapted for use in kitchen machines, with a
motor base that has at least one power take-off shaft, to
which drivable tools, stirrer arms, and attachments such as
mixing attachments, choppers, or the like, can be attached~
Kitchen machinesare known, for example West German
Patenschrift 25 51 842 of Bosch-Siemens Hausgerate GmbH, in
which the power unit is pivotably mounted on a stand. Here,
the power unit consists of a part which has a driving motor,
a stirrer arm, through which the motor shafts are conducted,
and a transmission head with a planetary gear. The trans-
mission head has two different power take-off shafts and can
be equipped with various tools, such as a stirring wisk or
a kneading fork, or also with working devices such as,
for example, a chopper. This known kitchen machine has
the disadvantage that, while the device is being used, its
high stand tends to vibrate, causing the unit to produce
excessive noise.
In another known kitchen machine, for example
West German Auslegeschrift 1,]32,689, July 5, 1962,
of Licentia Patent-Verwaltungs GmbH, the driving motor,
together with the power take-off shafts, is housed in a bo~-
shaped flat power base, whereby the power take-off is arranged
at the upper side of the power base. The working units
themselves are coupled with the power base through an
attachment socket that is equipped with interlock means.
However, this kitchen machine is not suitable for operating
a rotating stirring dish with a kneading and stirring hook
moving therein.
Finally, a multi~purpose kitchen machine is known
for example West German Auslegeschrift 1,083,993, June 23,
1960, of Fa~ Max Braun, which has a base extension arm
affixed at the base of the device, on which a removable
s-tirring dish is rotatably mounted, and with a transmission
arm, which can be set on the device base and which comprises
two power take-off shafts, one of which drives the stirring
dish from the top and the other of which drives the working
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tool. However, this multi-purpose kitchen machine has
the disadvantage that the transmission arm must ~e removed
from the device base when the stirring dish is needed.
According to one aspect of the present invention
there is provided a kitchen appliance which has a motor
base, a power take-off shaft extending outwardly from the
motor base with a retainer ring surrounding the power take-off
shaft and rigidly secured to the motor base, the retainer
ring havlng a plurality of radially and inwardly extending
pins. A tenslon ring is provided with ha~ a circular ~lange
portion with a plurality of recesses and a radially and
outwardly extending activation arm~ A clamp ring is also
provided together with means for interconnecting the tension
and clamping rings to thereby form a tension ring assembly,
wherein the retainer ring is clamped between the tension
and clamping rings such tat the tension ring assembly is
rotatab1e about the power shaft but is substantially
nondisplaceable in the longitudinal direction of the power
shaft. A tool attachment is provided which has a base with
radially outward extendiny protrusions for extending through
the tension ring recesses to secure the tool attachment to
the tension ring assembly. The kitchen appliance has a
container attachment having a base with a plurality of
recesses for receiving the pins to secure the container
attachment to the retainer ring.
According to ansther aspect of the present invention
there is provided a kitchen appliance having a motor base
with a driven motor powered outwardly extending power shaft
and a container attachment with a removable cover. Means
is provided for selectively coupling the container attachment
to the motor base and -the power take-off shaft. A locking
bolt is movably mounted on the container attachment and a
slidable member is disposed adjacent the locking bolt. A
switch is provided for selectively activating the driving
motor, and means is provided for linking the slidable member
to -the switch to thereby cause reciprocation of the member
upon actuation of the switch. A locking bolt displacement
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means displaces the locking bolt upon attachment of the
cover to thereby cause engagement of the locking bolt with
the slidable member. ~ncoupling of the container attachment
from the motor base and power take-off shaft is prevented when
the driving motor is in an activated state.
One feature o~ the present invention is based on the
aim of creating a power unit for a multi-purpose kitchen machine
to which a transmission arm, a stirrer arm or an attachment unit
can optionally be coupled. Here, when the attachment is
coupled in, the motor switch and the motor base are actuable
only when the container of the attachment is closed. The
transmission arm may be capable of being coupled with the motor
base in such a fashion that, in a first interlocking position,
it is retained tiltable at the motor base, and, only in a
second interlocking position (running position) is it rigidly
coupled with the motor base.
In a speci~ic embodiment of the invention, the tension
ring surrounds the retainer ring and is provided with an
activation arm, which is pivotally mounted and which is
secured agalnst moving in the longitudinal direction of
the power take-off ring, by means of a flange part and by means
of a clamping ring that is connected with said flange part.
The flange part has recesses through which penetrate the
radially extending protrusions of the base of a tool support
or of a stirrer arm, where said base can be inserted into
the retainer ring.
The retainer ring is advantageously provided with
the radially extending pins which act together with the
recesses and/or slots, which are provided on the base of the
container.
It is therefore possible optionally to attach to
the retainer ring the base of an attachment unit, which is
equipped with protrusions, which are h~ld by the flange part
when the tension ring in pivoted out, or else at the base
of another attachment which has slots, which are engaged by
pins after the tension ring has been pivoted out, where said
pins rigidly arres-t the base part. In a preferred embodiment,
the base is pivotally connected with the housing of the stirrer
arm through a hinge, whose hinge axis is disposed perpedicular
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to the longltudinal axis of the power take-off shaft. The
stirrer arm may have one or more fingers which, in the working
position of the stirrer arm, extend vertically downward, and
which have protrusions that grip down underneath the flange
part of the tension ring.
To insure that the tension ring uniformly and
reliably transmits to the motor base the tension forces that
act on the tension ring's flange part, when the attachment
unit or stirrer arm is coupled in, the tension ring, which
is pivotably mounted with respect to the motor base, may be
connected with the clamping ring through grooves, screws,
or stud bolts. The tension ring and the clamping ring
circularly grip the inner edge of an annular collar of the
housing of the motor ba~se.
In an embodiment which permits the reliable coupling
of an attachment unit, for example a chopper, with the motor
base, the activation arm of the tension ring has an opening
through which there penetrates a locking pin, which is movably
mounted at the container of the attachment unit and which is
movable over the cover so as to arrest the cover in the locked
position.
To keep the locking pin from unintended motion in
the sense of opening the lock, the locking pin may have a head
part with a groove, at that end which is turned away from the
cover. For locking purposes, this groove enters a slot,
which is disposed in a slide next to an entry opening. The
slide is movably mounted relative to the activation arm, whereby
the slide acts toyether with a blocking rod, which arrests or
releases the electrical switch for switching on the driving
motor~
In order that the attachment unit can be easily
removed from the motor base when the motor is switched off.
the slide may be acted upon by a spring, which acts on said
slide in the s~ense of unlocking it, whereby a blocking rod
is provided, which is movable over the electrical motor switch,
and which moves the slide in the locking sense against the
spring force.
Preferably, the cover of the device attachment may
be rotatably mounted and guided about the container a~is,
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after it has been placed on the container. A run-up ramp at
the edge of the cover moves the locking pin against the force
of a spring in the sense of making an interlock, and a locking
finger disposed at the edge of the cover penetrates through an
opening in the locking pin, and at the same time its head part
penetrates through the opening in the slide and the opening
in the activation arm.
To make sure that the cover of the attachment unit,
for example a chopper, cannot be opened when the motor is
switched on and can be removed from the container of ~he attach-
ment unit, a disclosed embodiment has a locking finger,
disposed at the edge of the cover, where said locking finger
has a claw, which, after the locking finger has penetrated
through the opening in the locking bolt, prevents rotation
of the cover about the container axis relative to the container.
In a specific embodiment of the in~ention, the flange
part of the pivotable tension ring has a concentric opening
for the base to penetrate, whereby a recess is provided that
extends radially outward from the opening, and through which
~0 the pxotrusion of the base of the stirrer arm penetrates when
it is in the starting position of its pivoting range and whereby
two other recesses are provided, which extend radially outward
from the opening, through which penetrate the protrusions
of the stirrer arm. In this design of the flange part of the
tension ring, the res~llt that, in the case of a stirrer arm
whose base has three protrusions, one of these protrusions
prevents an axial motion of the base in the retainer ring,
while the other two protrusions prevent a tilting of the
stirrer arm with respect to the base; is achievedO
More specifically, the base of the device attachment
has radially extended slots or recesses which are engaged
by the pins of the retainer ring, when the tension ring,
together with the device attachment is turned into the locking
positionO
One advantage of the power unit according to the
invention consists of the fact that all the tools, attachments,
and a]so the stirrer arm can be fastened on the u~er side
of the motor base. For this reason the motor base can have
a very flat, square-shaped, and thus stable design The stirrer
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arm, on the one hand, is coupled very solidl~ with the motor
base while it is in its working position and, on the other hand -
after the tension ring has been activated in the sense of open-
ing it - the stirrer arm can be telted away from the motor base
in such a fashion that simultaneously the connection between the
power take-off shaft and the drive shaft of the stirrer arm is
broken.
Another advantage of the power unit according to the
invention consists in the fact that a special electrical
braking device for the motor, which would brake the motor after
the cover of the attachment unit has been opened, can be dispensed
with, since opening the cover is possible only after the motor
has been switched offO
Finally, an advantage of the power unit according
to the invention consists of the fact that a large number of
different tools, attachments, or transmission arms can be
provided, all of which can be coupled with the motor base through
a single retainer ringO Consequently, no additional protective
attachments are necessary to cover the power take-off shafts
and/ox power unit couplings.
The invention permits a great number of embodiments,
one of these being schematically shown in the enclosed drawings.
In particular, the following are shown:
Figure 1 shows a partial longitudinal section through
the stirrer arm, pivoted into its working position, and through
a portion of the motor base with the power take-off shaft, and
a section through the retaining and tensioning device.
Figure 2 shows a longitudinal section through an
attachment, coupled with the motor base, with its container
and container cover in the locked positionO
Figure 3 shows the underside of the stirrer arm with
the two fingers and with the protrusions forlocking the stirrer
in its working position (with -the base removed).
Figure 4 shows a section through the retainer ring
with the tension ring and base for retaining the container of
the attachment accordina to the lines O-P in Figure 2~
Figure 5 shows a partial section through the gripping
part of the container of the attachment in Figure 2, accordin~
to lines Q-R~
.:
Figure 6 shows a top view of the flanged part of
the tension ringi
Figure 7 shows a partial view in the arrow direction
U according to Figure 4, of the base o~ the attachment unit.
As Figure 1 shows, a tension ring 4 is rotatably
mounted at the housing of the motor base 1 and it surrounds
the power take-off shaft 2. The tension ring 4 is held by a
clamping ring 8, which is fastened at the flange part 6 of the
tension ring 4 through stud bolts 23, 25, 26. The tension ring
4 is prevented from moving laterally by means of a collar 27
of the motor base lo A retainer ring 3 is held between the
flange part 6 or a ring 52 adjoining the flange part 6, on the
one hand, and a clamping ring 8 on the other hand. The st~d 53
of the retainer ring 3 serves as a bearing for the power take-
off shaft 20
The base 15 of the stirrer arm 17 is inserted into the
retainer ring 3 from the top, with protrusions 12, 13, 14
proJecting through recesses-9, 10, 11 of tension rinq 4 (see
Figure 6)o The protrusions 12 of the stirrer arm 17 is prevented
from moving in the arrow direction A by the flange part 6 or
by the ring 52, as soon as the flange part 6 of the tension
rinq 4 is pivoted from the starting position (position K) into
the position L (Figure 6) (about the axis A-B, Figure 1).
Figure 1 shows the stirrer arm 17 pivoted into its
working positionO Here, the fingers 16, 16a grip underneath
the flange part 6 with their protrusions 13, 140 They are
pressed by the flange part 6 against the shoulder 53 (inasmuch
as the tension ring 4 has been pivoted into the position M
with the flange part 6, Figure 6)I
The stirrer arm 17 is connected with the base 15
through a hinge 24, so that the base 15 can be pivoted about
the hinge pin 24aor into a rest position, in the arrow direction
Z, when the fingers 16, 16a or respectively their protrusions
13, 14 are released by the flange part 6.
~n its working position, the power take-off shaft 2,
which is provided with frontal gear teeth 54 engages the
corresponding gear teeth 55 of the transmission shaft 56~
~Iere, through the transmission of the stirrer arm 17 which
is not shown in more detail, the tool shaft 57 and the drive
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shart 5~ are coupled with the power take-off shaft 2 and ar~
moved by -the latter.
Figure 2 show~ the containe.r attac~ment 33 with
chopper blades 28, 29, which rota-te in a container 32, with a
cover 34 that is connected wi-th the contai.ner 32 throuyh a
bayone-t 59, with a handle section 60, a base 15a, and a blade
shaft 61O
Before inserting the base 3 into the retainer ring
15a, the cover 34 is turned about the axis 42 in the sense
L0 of closing it, whereby a solid interlocking connection is
established with the container by means of a hayonet 59. At
the same time, the locking finger 44 located at the edge 34a
of cover 34 engages the opening 45 of the locking pin 31 an~
arrests the pin 31 in the position sho~m in Figure 2. The
container 32, wich is inserted into the retaining ring 3
through opening 48 (F gare 6), can now be pivo-ted together
with the tension ring 4, since the locking pin 31 penetrates
through -the opening 37, 41, and the pins 18, 19, 20 (Figure 4),
thereby en-ter the locking slots 62, 63, 64 in the base 15a
(Figure 7~.
When the container 32, toge-ther with the tension ring
4, has been pivoted so far that the three pins 18, 19, 20
have -taken up their terminal posi-tions in the respective
locki.ncJ slots 62, 63~ 64, the motor (not shown in more de'tail~
can be switched on.. A peg disposed at the switching button of
the electrical rnotor switch, engages the opening 65, and~ during
the switch-on process, moves the blocking rod 39 in the arr~w
direction E, and thereby carries the slide 38 agains-t the force
of the spring 40O Thus the groove 36 of the lockin~ pin 31
enters the slot 37 and thus locks the locking pin 31 at the
activation arm 5 of the tension ring 4~ The head part 35, in
this position, prevents the locking pin 31 from moving in the
arrow direction N and thus, due to the action of claw 47 ~see
Figure 5), prevents the cover 34 from being opened while the
machine is activated. Only when the blockin~ rod 39 has been
moved back in the arrow direction F, iOe. when the motor is
switched o:Ef. can the container 32 be opened again, since
only in the position of the slide 38 or in the position of the
blocking rod 39, which are shown in Figure 2, can the locking
pin 31 move with its head part 35 from the openiny 41 in the
arrow direc-tion N (moved by the forcc of the spring 46)
As Figures 2 and 4 show, a detent ~rotrusion 21
is provided at the tension ring 4 or at the flange part 6, and
is acted upon by a spring. In the locked position M (see
Figure 6), the detent protrusion engages a recess in the
retainer ring, and thus secures the tension ring 4 agains-t
unintended pivoting. A stop that is rigidly fixed to the motor
base 1 is designated by 66, and this stop prevents the tension
ring 4 with the activation arm 5 from turning too far in the
arrow direction V (Figure 4~ e. in the sense of making a
lock.
While the invention has herein been illustrated by
way of de-tailed embodiment, it will be appreciated that various
substit~tions of equivalents may be made with~ut departiny
from the spirit and scope of the invention as se-t forth in the
following claims.
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