Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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~3ACKGROUND OF THF. I`IVENTI.ON~_
In recent years, many electronic appliances, ~oth
consumer and pro~essional, have been automated. This means
that many functions that are controlled by the use can also
be controlled by an'internal program of the appliance. In
older non-automated appliances, rotary potentiometers were
used to control many functions. Automation o~ a unit
requires the use o~ knobs or buttons that allow an automated
change of parameters and would also work as manual controls.
Traditional potentiomcters usually cannot be used because
they can be set only by an operator. Users are accustomed to
a traditional form of a knob as a control device. By turning
a knob, a user can increase or decrease the setting of a
parameter. An automated control device should work in a
~imilar way, There are several solutions presently being
used, all of which have various disadvantages. '~
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One automated design is an array o~' "up and down"
push-buttons, The basic disadvantage o~ the present
automated solutions is the inability to indicate the current ~ '
position of the control as is possible with potentiometers.
In traditional potentiometers, the actual position o~ the
knob is shown by a marker. This allows the user to determine ' '
how the control is set. Nothing similar is possible with
push-buttons, unless an ~d~liti nal display i9 provided,
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~ Another example o~ an automated control is a
motorized potentiometers. A motorized potentio~eter has the
disadvantage that a driving mo~or is mechanically coupled
with the potentiometer shaft. Therefore, there are two ~-
factors determining knob position, namely, the user and the
motor. This complicates the additional circuitry and makes
the whole product very unreliable and expensive.
A third known design of automated control is a ; ~
rotary multipositioned switch with no mechanical stop, ~: -
surrounded by light emitting diodes (~ED). With this
control, the user turns the switch and the position of the
switch is shown by one of the LEDs, which is activated by
associated electronics. This construction has the
disadvantages of high cost and inconvenient and unclear
reading.
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SUM~1ARY OF THE INVENTION:
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Accordingly, it is an object of the present
invention to provide a control which combines advantages of a
traditional knob with an easy automated setting of knob
position.
Pursuant to this object, and others which will
become apparent hereafter, one aspect of the present
inventlon resldes in a control device having a knob made up
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of at least two independently rotatable elements, namely, a
knob body and a knob cap. The device further includes a
reader and a driver that have coaxial independently revolving
shafts, similar to a double-shafted potentiometer. The
reader shaft is mechanically coupled to the knob body, while ;
the driver shaft is coupled to the knob cap. ;~
The shafts are freely movable independently o~ each
other without mechanical interference therebetween, as are
the knob cap and ~nob body.
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The knob body is manually set by an operator, and ; -~
the knob cap has a position marker which shows the operator
the "subjective" position of the kno~. The reader reads the
actual position or movement of the knob body and sends this
data to an electronic circuit. The circuit puts out
corresponding data which is read by the driver, which in turn
sets the position of the knob cap.
The cap and body have no mechanical stop, i.e.,
they can revolve without restraint. Data outgoing from the
reader is processed by the electronic circuit and may differ
rom data incoming to the driver. This means that the
movement of cap does not necessarily have to follow the
movement of the knob body. It is only the electronic circuit
that determines the cap position setting, and it is only the
operator who can move the knob body. This separation of
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funetions of the knob body and the Xnob cap is es~ential for
the invention.
The novel features which are considered as ~-
characteristic for the invention are set forth in particular :~
in the appended claims. The invention itself, however, both
as to its construction and its method of operation, together
with additional objects and adva~tages thereof, will be best
understood from the following description of specific
embodiments when read in connection with the accompanying
drawings.
~PIE~ DESC13IPTION 01' THE DF~AWII~GS:
Fig. 1 is a perspective view o~ a control device
pursuant to the present invention;
Fig. 2 is a section along the line II-II of Fig. l;
Fig. 3 is an exploded vlew of the device of Fig. l;
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Fig. 4 schematically illustrates the flow of data
in the devlce;
Figs. 5 - 6b shows various embodiments of the knob
and cap; and
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I Fig. 7 is a view similar to Fig. 1, of an
additional embodiment of the control device.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS: ~
Figs. 1 - ~ illustrate a control device having a ~-
plastic knob body 2 with an independent cap 1, a reader 3,
and a driver 4. The reader 3 is an optical encoder having a ~;
radially striped disk with an opto-electronic device capable
o~ reading the movement of the disk and its direction. The
knob body 2 is connected with the reader 3 by a shaft 5, and
the disk is attached to the shaft 5 so that the reader 3
reads the movement of the ~nob body 2.
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The driver 4 is a miniature stepper motor attached
to the cap 1 by a shat 6. A circuit 7 is provided between
the reader 3 and the driver 4. The circuit 7 receives data
from the reader 3 and feeds corresponding data to the driver
4.
The two element knob can be used for a wide variety
of applications, and can be designed in several ways. For
example, the cap 1 does not have to be the element moved by
the driver 4. As shown in Fig. 6, a ring 8 at the bottom of
the knob body 2 can take the place of the cap 1. The ring 8 ~ -
can also be situated at any other point along the knob body
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~ As Figs. 5 - 5c, 6a and 6b show, a marker 9 is
provided on the cap 1 or ring 8 to show position of the knob -:~
capl or ~ing B.
Fig. 7 shows an embodiment having additional knob
10 and additional cap 11 which are respectively connected to
a reader 13 and a driver 12 by independent shafts coaxial
with shafts 5, 6. Such a multiple arrangement operates on
the same principal as that of Fig. 1. ~ :
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: While the lnvention has been illustrated and
described as embodied in a control device, it is not intended
to be limited to the details shown, since various
modifications and structural changes may be made without
departing in any way from the spirit of the present
invention.
Wlthout further analysis, the foregoing will so
fully reveal the gist of the present invention that others
can, by applying current knowledge, readily adapt it for
various applications without omltting features that, from the
standpoint of prior art, fairly constitute essential
characteristics of the generic or specific aspects of this
invention. ;
What is claimed as new and desired to be protected .:
~: by letters patent is set forth in the appended claims, ~
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