U.S. patent number 3,662,618 [Application Number 05/040,885] was granted by the patent office on 1972-05-16 for instrument knob having integral detent mechanism and panel mount socket means.
This patent grant is currently assigned to International Standard Electric Corporation. Invention is credited to Heinz Ernst Johannes Kroll, Horst Dieter Ziegler.
United States Patent |
3,662,618 |
Kroll , et al. |
May 16, 1972 |
INSTRUMENT KNOB HAVING INTEGRAL DETENT MECHANISM AND PANEL MOUNT
SOCKET MEANS
Abstract
A rotary instrument knob with integral detent and stop means. An
integral bushing or "termination socket" is provided whereby the
knob may be assembled onto a panel in a rotationally predetermined
orientation. The detent mechanism includes an indentation contour
on a flange end of the termination socket within the knob body. The
knob body is constructed in sections whereby the assembly of stop
rings, detent balls and spring retaining means may be accomplished
and then enclosed within the knob body by snap-fit assembly of the
knob body shell over those elements.
Inventors: |
Kroll; Heinz Ernst Johannes
(Heroldsberg, DT), Ziegler; Horst Dieter (Nurnberg,
DT) |
Assignee: |
International Standard Electric
Corporation (New York, NY)
|
Family
ID: |
5735794 |
Appl.
No.: |
05/040,885 |
Filed: |
May 27, 1970 |
Foreign Application Priority Data
|
|
|
|
|
Jul 31, 1969 [DT] |
|
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P 19 27 901.7 |
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Current U.S.
Class: |
74/527; 74/553;
116/315 |
Current CPC
Class: |
G05G
1/12 (20130101); H01H 21/50 (20130101); G05G
1/10 (20130101); H01H 3/08 (20130101); H01H
19/03 (20130101); Y10T 74/20636 (20150115); Y10T
74/2084 (20150115); H01H 19/11 (20130101) |
Current International
Class: |
H01H
3/08 (20060101); H01H 19/00 (20060101); H01H
3/02 (20060101); H01H 21/00 (20060101); H01H
19/03 (20060101); H01H 21/50 (20060101); G05G
1/10 (20060101); G05G 1/12 (20060101); G05G
1/00 (20060101); G05g 005/06 () |
Field of
Search: |
;74/527,553 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: O'Dea; William F.
Assistant Examiner: Shoemaker; F. D.
Claims
What is claimed is:
1. A rotary shaft control instrument knob having self-contained
detenting mechanism within the body of said knob, comprising: a
termination socket in the form of a bushing having a flanged end
and a bore therethrough coaxial with the axis of rotation of said
knob to accept the said shaft to be controlled, with rotational
freedom, said socket being adapted to be inserted and retained
partly through an opening in a panel with said flanged end
projecting into the interior of said knob body; means for retaining
said knob body against substantial axial movement while permitting
rotation thereof with respect to said termination socket; shaft
lock means within and rotationally keyed to said knob body for
securing rotational continuity between said knob and said shaft;
detent means comprising a series of indentations constituting an
engaging contour distributed circumferentially about the face of
said flange, and at least one rolling member of circular cross
section in at least one plane operative against said indentations;
resilient means operating against the inside of said knob body for
maintaining a compressive force between said rolling member and
said flange; guide means keyed to said knob body for imparting
circumferential motion to said rolling member as said knob and said
shaft are rotated together, whereby said rolling member tends to
seat in successive ones of said indentations to produce detenting
at positions corresponding to predetermined angular positions of
said knob and shaft.
2. Apparatus according to claim 1 including a keying arrangement
between the external body of said socket and the perimeter of said
opening for retaining said termination socket within said opening
in said panel and for locking said socket in place
rotationally.
3. Apparatus according to claim 2 in which said retention of said
socket in said opening is effected by a locking ring inserted in a
circumferential slot in the external perimeter of said socket, said
ring bearing against said panel on the side thereof opposite the
installation of said knob, and in which said socket includes a
shoulder bearing against said panel on the opposite side thereof,
whereby said socket is axially locked in position.
4. Apparatus according to claim 1 including an at least partially
radially outwardly projecting finger connected to the outer
perimeter of said socket within said knob body and at least one
stop ring keyed to said knob body and having at least one radially
inwardly projection oriented to engage said outwardly projecting
finger at a predetermined angular position of said knob and
shaft.
5. Apparatus according to claim 1 having two of said stop rings
stacked axially and each having multiple peripheral keying means
whereby they may be separately keyed to said knob body to provide
first and second angular limits of operation of said knob and
shaft.
6. Apparatus according to claim 4 in which said knob body is
composed of at least two axially assembled hollow parts, a first of
said parts containing said stop ring, whereby said knob may be
assembled by emplacing said first part in proximate position over
said panel opening and inserting said socket through said first
part and said panel.
7. Apparatus according to claim 6 including a second hollow knob
body part axially snap-fitted into said first part, said second
part including an internal surface in a plane normal to the axis of
said knob to face said termination socket flange to carry said
resilient means bearing against said circular cross section
member.
8. Apparatus according to claim 7 in which said shaft lock means
are included in said second part, whereby said knob may be further
assembled by emplacing said rolling member of circular cross
section against said engaging contour and emplacing and locking
said second part to said shaft thereby bringing said resilient
means to bear against said circular cross section member.
9. Apparatus according to claim 8 having at least two circular
cross section members substantially diametrically opposite in
position along said engaging contour and said members are
balls.
10. Apparatus according to claim 9 in which said resilient means
comprises a pressure ring inserted against said balls opposite said
engaging contour and a helical spring bearing against said pressure
ring and caged in an annular groove inside said knob body second
part.
Description
The present invention relates to a rotary knob capable of being
mounted to the control shaft of an apparatus and which, on its side
facing the apparatus, is provided with a hollow space for receiving
an arresting or click-stop device serving to fix the positions of
rotation of the shaft. Such types of rotary knobs are required
above all for rotary switches comprising a control knob mounted to
the control shaft thereof, and by which certain switching positions
of the shaft can be adjusted.
The fixing or arresting of switching positions of a control shaft,
as is well known, is effected with the aid of a click-stop or
arresting device which is joined to the apparatus to be operated,
or which, e.g., may be built into the apparatus. In conventional
types of rotary switches this click-stop device consists of biassed
or pretensioned balls which, for the purpose of effecting their
engagement, are provided with fixed arresting positions. It may,
for example, be surrounded by a spacing portion forming part of the
housing, whereas the remaining parts of the housing are composed of
stator parts which are piled on top of each other, surrounding the
shaft. Electric rotary switches of this type and construction have
already been extensively miniaturized, in that the parts thereof
are being designed very small. This miniaturization, however, can
only be carried out within certain limits in view of the occurring
actuating forces, even if the latter are being kept as small as
possible, because there have to be avoided any unwanted variations
or changes in shape of the switch, or of the parts which are
important for performing the functions thereof, respectively. The
result of this is that known types of rotary switches cannot be
further reduced in size.
For avoiding this disadvantage is has already been proposed to
provide in the rotary knob of the rotary switch a hollow space
which, on its side facing the apparatus to be operated, is designed
as an engaging contour in which the hold members slide which, in
turn, are guided by an engaging or arresting body which is arranged
in this hollow space. This engaging or arresting body, at the same
time, is provided with means for allowing it to be mounted to the
apparatus.
The foregoing proposal was based on the consideration that the
rotary knob, for serving as a handle, must have a certain size, but
that the space enclosed thereby, is not fully utilized, whereas the
apparatus itself is supposed to be of a space-saving construction.
The present invention is based on the same consideration and has
for its object to provide a rotary knob suitable for being mounted
to a shaft and which, at the same time, contains a click-stop
device, so that it will thus become possible for certain devices in
which a shaft is to be turned or adjusted, to be miniaturized to
very small dimensions. According to the invention, and with respect
to a rotary knob of the type mentioned hereinbefore, this is
accomplished in that the engaging member of the click-stop device
is a termination socket which is provided with a shaft-passage
opening and is joined to a rotary knob in the axial direction, with
this termination socket, on its side facing the apparatus, is
provided with means allowing to be mounted to the apparatus and, on
its side not facing the apparatus, is designed to carry an engaging
contour in which resiliently supported holding (engaging or
arresting) members which are guided by a holding body (guide ring)
which is coupled in a motion-locking fashion to the shaft, are
permitted to slide.
The invention offers the advantage, according to which it is
possible, merely by interchanging the rotary knob, to provide
certain devices in which a control shaft is to be fixed or engaged
in predetermined rotary positions, with a click-stop or arresting
device. In so doing, it is still possible, as up to now, for the
rotary knob to be mounted from one side. A further advantage
capable of being achieved by the invention, resides in the fact
that such types of devices may have very small dimensions which
they are required to have, for example, when intended to be built
into printed circuit boards.
Moreover, the present invention offers the advantage that a
limiting stop function which might be required in certain cases,
may be replaced from the apparatus into the rotary knob, thus
resulting in a further saving of space in the apparatus. According
to an advantageous further embodiment of the invention, this is
accomplished in that into the hollow space of the rotary knob there
is inserted a limiting stop device which, in a motion-locking
fashion, is joined thereto, and with the aid of which it will
become possible to prevent the shaft from being turned beyond a
predetermined angle.
For the purpose of enabling a better understanding of the
invention, these and advantageous further embodiments of the
invention will now be described in detail with reference to an
example of embodiment shown in FIGS. 1 to 3 of the accompanying
drawings in which:
FIG. 1 shows a longitudinal section taken through a rotary knob
comprising a click-stop device and a limiting-stop device according
to the invention;
FIG. 2 shows a top view taken in the direction indicated by the
arrow "A," of this rotary knob, with the front plate or panel
removed, and
FIG. 3 shows a cross section taken along line B-C taken through the
rotary knob shown in FIG. 1.
According to FIG. 1, the shown rotary knob 10 comprises an internal
housing 20 and an external housing surrounding the latter at least
partly in a form-locking manner, and composed of three parts 30,
40, 50 capable of being placed on top of each other, with the
reference numeral 30 indicating the bottom of the housing carrying
the internal housing, and with the reference numeral 40 indicating
the sleeve of the housing provided with corrugated handling areas
41, and with the reference numeral 50 indicating the cover of the
housing (housing cap) terminating the sleeve of the housing at the
top end. By means of a resilient holding or retaining pawl 51 this
housing cap is detachably latched to the sleeve of the housing 40.
The bottom of the housing 30 meets with one face sided end against
the neighboring face side of the sleeve of the housing 40 and is
likewise detachably mounted in the internal housing by means of a
snap-action joint. To this end the detachable bottom of the housing
30 is provided on its inside with a circular groove 31, and the
internal housing 20 is provided on its outside facing the bottom of
the housing, with a circular cam 21 fitting into the circular
groove 31. An indicator 32 molded to the bottom of the housing 30
serves to indicate the respective rotary position of the rotary
knob 10. For readjusting and fixing in position of the indicator
32, the circular cam 21 is provided along its circumference with
slots 22 arranged in an angular division corresponding to the
engaging positions of the rotary knob 10, with these slots 22
capable of being engaged by a radial inwardly directing nose
portion 33 as molded to the inner circumference of the detachable
bottom part 30 of the housing.
The mechanical connection between the sleeve of the housing 40 and,
consequently, of the rotary knob 10 and the control shaft 60 of the
apparatus to be operated, is effected via a collet or holding
fixture 70 which is provided with a shaft-passage opening 71, which
is accommodated in a hollow space 23 not facing the apparatus, and
forming part of the internal housing 20. To this end the sleeve of
the housing 40 comprises a collar 42 extending into this hollow
space, to which the tightening or tension nut 80 of the collet or
holding fixture 70 is pressed via a shim plate (washer) 90 arranged
therebetween.
Both the tightening (or tension) nut 80 and the shim plate (or
washer) 90 are arranged in a hollow space 52 of the housing cap 50
or in a hollow space 43 adjacent the housing cap, of the sleeve of
the housing 40 respectively. Since the shim plate 90, in turn, is
lying closely against one neighboring face side of the sleeve of
the housing 40, this simultaneously establishes a mechanical
connection between the internal housing 20 and the external sleeve
of the housing 40.
Besides the collet or holding fixture 70, i.e., parts of the
arrangement for effecting the axial fixing, the internal housing 20
contains the entire click-stop or arresting device for retaining
the positions of rotation. As an engaging or arresting member of
the click-stop or arresting device there is used a termination
socket 100 which is connected to the rotary knob 10 in the axial
direction, and is provided with a shaft-passage opening 101, hence
which has to be supported stationarily, e.g., on the front panel
110 of the apparatus to be operated. For this purpose the
termination socket 100 comprises one part projecting out of the
internal housing 20, on which means are provided for allowing
mounting to the apparatus. In the example of embodiment shown in
FIG. 1, therefore, there are provided on this part, a shoulder 102
resting against the front panel 110, and a circular groove 103
arranged before the shoulder, for receiving a not shown guard or
retaining plate. In order to avoid relative movements between the
termination socket 100 and the front panel 110 of the apparatus,
the termination socket is moreover provided with a stop element 104
which, for example, is designed to have the shape of a nose
engaging the front panel. On the side not facing the apparatus,
hence in the inside of the knob, the stop element 104 may
simultaneously serve as a stationary limiting stop for restricting
the rotary movement of the control shaft 60. The shown stop member
104 enables a particularly simple torsion-proof mounting of the
termination socket 100 to the apparatus or the front panel 110
thereof respectively, because during assembly of the rotary knob
10, the stop member merely has to be inserted into a corresponding
recess provided in the front panel. The necessary torsional
resistance, however, may also be obtained in any other way, for
example, by providing a recess in the termination socket 100 which
is then engaged by a nose or engaging portion arranged on the front
panel 110 of the apparatus. The termination socket 100 can also be
joined in a completely different way to the apparatus, for example,
by way of screwing or cementing (glueing). The axial adherence
between the termination socket 100 and the control shaft 60 is
secured by a guard or retaining ring 120 which is arranged in an
annular groove 24 of the internal housing 20, lying closely against
a collar 105 of the termination socket within the range of its face
side pointing into the hollow space 27 of the internal housing.
In order to achieve an engaging or arresting turning of the rotary
knob 10, it is necessary to provide the termination socket 100
acting as the engaging or arresting member, with an engaging or
arresting contour 106. This engaging contour in which holding or
engaging members slide which are resiliently supported and retained
and guided in a suitable way, is arranged on the face side of the
termination socket 100 not facing the apparatus or the front panel
110 thereof respectively. As suitable hold or engaging members
there may be considered, in particular, balls 130, 140. The holding
body guiding these balls, is designed to have the shape of a ring
150 surrounding the control shaft 60 and in the circular recesses
of which the balls are supported. In order to ensure that this
guide ring 150 is being taken along by the housing 20 capable of
rotating about the termination socket 100, when actuating the
control shaft 60, it is designed to engage with its segment-shaped
projections 151 as arranged along its outer circumference, the
correspondingly adapted cutouts or recesses 25 as arranged on the
inside of the housing 20.
By a finger (finger-shaped projection) 152 extending inwardly and
arranged on the inner circumference of the guide ring 150, and
which, in a form-locking manner, engages a longitudinal groove on
the control shaft 60, both the engaging and the shaft position can
be fixed in relation to one another. To this end, also the inner
circumference of the guide ring 150 may be adapted to the profile
of the control shaft, e.g., a flat shaft. This might be of
significance, for example, in cases where rotors are mounted on the
control shaft 60 which are intended to be turned as well, and carry
contact members, which in turn, cooperate with stator contact
members by performing a corresponding opening and closing. Upon
actuating the control shaft 60, the balls 130, 140 are advanced in
a step by step manner from engaging point to engaging point, for
fixing thus the position of rotation of the shaft, and for bringing
certain stator and rotor contact members into or out of contact
respectively. The arrangement of the rotors and stators and of the
contact members thereof can be made in the usual way, and is of no
significance to the present invention.
In the example of embodiment according to FIG. 3 two diametrically
opposing, circular openings are arranged in the guide ring 150 at
an equally spaced relation from the shaft 60. In this way it is
accomplished that the engaging or arresting pressures of the two
balls 130, 140, will annul each other with respect to the loading
of the control shaft 60. In order to produce the necessary engaging
pressure, a ball-retaining disk 160 which is provided with a
shaft-passage opening, is placed by a flexible device against the
balls 130, 140. This is accomplished with the aid of a helical
compression spring 170 which is retained and guided concentrically
in relation to the shaft 60 in a circular groove 26 as provided in
the housing 20, and extending in the axial direction. This helical
compression spring thus presses the balls 130, 140 against the face
side wall of the termination socket 100 and, consequently, against
the engaging contour 106. By the holding arrangement of the helical
compression spring 170 which is permanently concentrical in
relation to the shaft 60, the ball-retaining disk 160 is uniformly
pressed against the balls 130, 140, thus resulting in a particular
precise and easy-going engagement or arresting in all positions of
rotation of the rotary knob 10 at the required actuating moment.
The invention, of course, is in no way restricted to the feature of
employing two such engaging or arresting members only. Moreover, it
is equally well possible to employ rollers instead of the balls as
holding, engaging or arresting members.
In order to restrict the rotary motion of the control shaft 60,
there are provided the limiting-stop rings 180, 190 which, with
segment-like projecting portions 181 (or 191 respectively) as
arranged along the outer circumference thereof, engage the
correspondingly adapted recesses or cutouts 25 on the inside of the
housing 20. Appropriately, there are used two such limiting-stop
rings 180, 190 which, as may be taken from FIG. 1, are placed on
top of each other, and are capable of being turned by a certain
angular division with respect to the housing of the rotary knob. On
their inner circumference, these two limiting-stop rings 180, 190
each comprise an inwardly extending arresting catch 182 or 192
respectively. These two arresting catches 182, 192 together form an
angle which is determined by the number of desired positions of
rotation (switching positions), and cooperate with a stationary
limit stop, such as the stop element 104, in the sense of
restricting the rotary motion of the control shaft 60 in both
directions. For example, in the case of a 12-position click-stop
device, there is used a limiting-stop device in which the two
arresting catches 182, 192 together form an angle of 30.degree.. By
differently inserting the two limiting-stop rings 180, 190,
however, it is possible to readjust the limit stops in any
arbitrary fashion. Moreover, the limit stop may also be completely
omitted by removing the rings 180, 190. It is also possible to use
one single ring instead of two such rings, which then comprises two
arresting catches 182, 192. In this case, of course, the distance
or spaced relation between the limiting stops can no longer be
readjusted. In cases where only one limit stop is provided, one
such limiting-stop ring 180 or 190 with one arresting catch 182 or
192 is sufficient. In this case the shaft 60 can only be turned by
360.degree., with the respective arresting catch 182 or 192 for
restricting the rotary motion, appearing on opposite sides of the
stationary limiting stop, e.g., at the stop element 104.
The axial fixing of the limiting-stop rings 180, 190 in relation to
the control shaft 60 is effected, on one hand, by the guard or
retaining disk 120 as arranged inside the housing 20 of the rotary
knob and, on the other hand, by the inwardly projecting joined-on
portion 34 of the bottom of the housing 30. For readjusting the
limiting-stop rings 180, 190 it is then merely necessary for the
bottom of the housing 30 to be removed temporarily; this, however,
will not affect the functioning of the click-stop or arresting
device.
The rotary knob 10 according to the invention can be mounted in the
usual way to a control shaft 60. It is merely required to provide
any suitable kind of device for preventing the termination socket
100 from being turned. As already mentioned, this means for
preventing a rotation can be formed by a recess or cutout provided
in the front panel 110 of the apparatus. Alone by the employment of
one rotary knob according to the invention, switches or other
devices capable of being operated by a shaft, can be provided with
a click-stop or engaging device.
The rotary knob 10 as shown in FIGS. 1 to 3 can be made of any
suitable material. Preferably, however, the three outer parts of
the housing of the rotary knob 10, i.e., the bottom 30, the sleeve
40, and the cap 50 of the housing are made from a suitable
injection molded plastic material, whereas the internal housing 20,
as well as the termination socket 100 are made from a die-casting
zinc alloy (injection-molded or die-cast zinc).
* * * * *