U.S. patent number 3,668,338 [Application Number 05/111,545] was granted by the patent office on 1972-06-06 for miniature axial bridging rotary switch with improved housing.
This patent grant is currently assigned to Grayhill, Inc.. Invention is credited to Thomas J. O'Malley.
United States Patent |
3,668,338 |
O'Malley |
June 6, 1972 |
MINIATURE AXIAL BRIDGING ROTARY SWITCH WITH IMPROVED HOUSING
Abstract
Multi-position electrical switch including switch sections or
decks arranged so that any desired number of sections can be used.
Each section includes a rotor for selectively bridging switch
contacts which can be arranged in different manners as required in
different applications. A large number of switch positions, for
example, 24, can be provided in a very small switch structure. The
individual contacts for the different positions are embedded in a
plastic insulating member to provide a solid insulated support
therefor.
Inventors: |
O'Malley; Thomas J.
(Brookfield, IL) |
Assignee: |
Grayhill, Inc. (La Grange,
IL)
|
Family
ID: |
22339128 |
Appl.
No.: |
05/111,545 |
Filed: |
February 1, 1971 |
Current U.S.
Class: |
200/11A; 200/11D;
200/14 |
Current CPC
Class: |
H01H
19/58 (20130101); H01H 19/64 (20130101) |
Current International
Class: |
H01H
19/00 (20060101); H01H 19/64 (20060101); H01H
19/58 (20060101); H01h 019/58 (); H01h
021/78 () |
Field of
Search: |
;200/11A,11D,14,17R,168S |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Scott; J. R.
Claims
1. A rotary multi-position electrical switch structure including in
combination,
a molded cylindrical insulating member having a plurality of
conductors molded therein, said conductors being substantially
uniformly radially spaced about said insulating member and having
external terminal portions and internal contact portions,
an insulating plate engaging one end of said cylindrical insulating
member, contact means in engagement with said insulating plate,
a rotor structure within said insulating member having a rotary
insulating member and at least one conducting contact moved by said
member, said contact having portions selectively engaging said
contact portions of said conductors and said contact means, and
an insulating disc engaging said cylindrical insulating member at
the end thereof opposite to said end engaging said insulating
plate, said disc having a portion extending into said cylindrical
insulating member and ridges extending between said contact
portions, said disc and said cylindrical member having
interengaging portions to insure that said disc is in a
predetermined radial position with respect to said cylindrical
2. A switch structure in accordance with claim 1 wherein said
internal contact portions have raised ends, and said contact of
said rotor structure is U-shaped and has a first end adapted to
selectively engage said contact portions and a second end adapted
to engage said contact
3. A switch structure in accordance with claim 1 wherein said
insulating disc extends within said cylindrical insulating member
with one surface
4. A switch structure in accordance with claim 1 wherein said
ridges of said insulating disc have heights to be engaged by said
contact of said rotary member when said contact moves from one of
said contact portions to another, and wherein said ridges are
constructed of a material which acts
5. A switch structure in accordance with claim 4 wherein said
insulating disc has a central hub connected to said ridges and
cooperating therewith and with the inside surface of said
cylindrical insulating member to form
6. A switch structure in accordance with claim 1 wherein said
insulating plate has a plurality of recesses therein and said
contact means includes a plurality of flat conductors positioned in
said recesses, with each conductor having a radial extent to be
aligned with a plurality of said
7. A switch structure in accordance with claim 6 wherein said rotor
structure has a plurality of conducting contacts equal in number to
the
8. A rotary electrical switch structure including in
combination,
a base member having an operating shaft supported thereby and means
coupled to said shaft providing predetermined switching
positions,
a plurality of switch decks mounted on said base member each
including a cylindrical insulating housing section having a
plurality of conductors molded therein in radially spaced
positions, an insulating disc in predetermined positional
engagement with said housing section and having a central opening
therein, contact means supported in fixed position with respect to
said conductors, and a rotor within said housing section including
a movable contact selectively bridging said conductors and said
contact means, said rotor including a rotary insulating member
having a hub extending into said central opening in said insulating
disc, and
drive means coupling said operating shaft to said rotor of each of
said
9. A switch structure in accordance with claim 8 wherein said
conductors have portions extending outside said cylindrical housing
section forming terminals, and portions extending within said
housing section forming fixed contacts which are engaged by said
movable contact of said rotor.
10. A switch structure in accordance with claim 8 wherein said base
member has a plurality of openings therein and including a pair of
stop pins adapted to be positioned in said openings, and a stop
plate coupled to said operating shaft having a stop arm adapted to
engage said stop pins to limit rotation of said operating shaft,
with the extent of rotation being
11. A rotary switch structure in accordance with claim 1 wherein
said insulating disc has a central opening therein, and said rotary
insulating member has a hub extending into said central opening.
Description
BACKGROUND OF THE INVENTION
A miniature multi-position rotary switch structure is described and
claimed in my prior U.S. Pat. No. 3,297,836, issued Jan. 10, 1967.
This switch has been highly successful in actual use and is being
produced in large quantities by Grayhill, Inc., assignee of the
invention. As described in the patent, this prior switch structure
provides 12 switch positions, and it has also been constructed with
10 switch positions.
There has been a significant demand for miniature rotary switches
having more than 12 positions. More specifically, switches are
required in various applications which have 16, 20 and 24
positions. The switches which are available and which have such a
large number of positions have been quite large, substantially
larger than the switches constructed in accordance with U.S. Pat.
No. 3,297,836. Although attempts have been made to provide smaller
switches with 16 or more positions, the switches have not been
entirely satisfactory in operation and have not been of a
construction to provide the contact arrangements which are required
in many applications.
SUMMARY OF THE INVENTION
It is, therefore, an object of the present invention to provide a
miniature multi-position rotary switch which is of simple
construction and which can have as many as 16 or more switch
positions.
Another object of the invention is to provide a multi-position
rotary switch having a large number of switch positions, with the
contacts required for such switch positions being embedded in
closely spaced relation in an insulating support housing, and
insulated from each other thereby.
A further object of the invention is to provide a miniature
multi-position rotary switch which has a plurality of switch
sections or decks, with a common operator therefore and independent
contact structures, with each deck having a large number of switch
positions.
In accordance with the invention, a miniature rotary electrical
switch is provided including a base member to which a rotary
actuator is connected, and which has a detent structure and a stop
structure coupled thereto. One or more switch decks are connected
to the base member, with the actuator extending through the switch
decks to move the rotors thereof. Each switch deck includes a
cylindrical insulating housing section having a plurality of
conductors embedded therein at radially spaced positions. The
conductors have portions extending outside the housing forming
terminals, and portions extending inside the housing forming switch
contacts. A rotor within each housing section has one or more
contacts therein which selectively engage the contacts of the
conductors embedded in the housing, and one or more other contacts
provided on a plate which closes one end of the housing section.
The other end of the housing section is closed by a disc having
ridges extending therefrom into the spaces between the switch
contacts. The ridges insure that the contacts are insulated from
each other and form recesses or wells for receiving foreign
particles, so that such particles are removed from the vicinity of
the switch contacts. The ridges may extend into the path of the
moving contacts, and serve to clean such contacts as they move from
one position to the other.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a miniature rotary multi-position switch in
accordance with the invention;
FIG. 2 is a cross-section view of the switch of FIG. 1;
FIG. 3 is an exploded view of the switch of FIG. 2 showing only one
switch deck;
FIG. 4 is a detail view showing the insulating rotor 49 and the
U-shaped contact 50;
FIG. 5 illustrates the construction of the insulating disc of the
switch; and
FIG. 6 illustrates a modification of the contact structure.
DETAILED DESCRIPTION
In FIG. 1 there is shown a miniature multi-position rotary switch
of the invention which includes a base housing member 10 having a
threaded tubular bushing 12 extending therefrom for mounting the
same on a panel. A rotary operating shaft 14 extends through the
bushing 12 for controlling the position of the switch. A plurality
of switch sections or decks 15 and 16 are shown mounted to the base
member 10 by a plurality of bolts 18. A cover plate 20 is provided
after the last switch section 16. It is to be pointed out that any
number of switch decks, from 1 to 12 or more, can be used, with the
deck 16 being broken away to indicate that additional decks can be
used. The switch is shown enlarged in the drawing to better
illustrate the structure. A 24 position switch as illustrated may
have an outer diameter of about 11/4 inches, and the thickness of
each switch deck is about one third of an inch.
FIG. 2 is a cross-section view of the switch of FIG. 1, and FIG. 3
is an exploded perspective view showing such a switch with a single
switch deck. As shown in FIG. 2, the operating shaft 14 has a slot
22 in the end thereof into which an actuating blade 24 is keyed.
The blade 24 is held in position with an end thereof in the slot 22
by the cover plate 20. The base member 10 of the switch forms a
housing in which a detent mechanism 27 is positioned. This
mechanism includes an elongated rotor (FIG. 3) with opposing holes
therein in which springs 28 are positioned. The springs 28 force
balls 30 outwardly against the wall 31 of the housing recess 26,
and has ribs thereon (FIG. 3) to form detented positions. The
detent mechanism 27 is turned by the blade 24 as the switch
operating shaft 14 is rotated.
A stop plate 32 is also provided in the recess 26 in the base
member 10. This plate is also keyed to the blade 24, and has a
projecting stop arm 33 which engages pins 34 in the base 10 to
limit the rotary movement of the operating shaft 14. The pins 34
may be positioned in any desired ones of the openings 35 in the
base 10, to limit the rotary movement of the shaft 14, as may be
required.
Each switch section or deck includes a cylindrical housing member
36 which is molded of insulating material. This member has a
plurality of conductors 38 embedded therein which are substantially
uniformly radially positioned about the cylindrical housing 36. The
conductors have outwardly extending terminal portions 39 and
inwardly extending contact portions 40. The contact portions 40 may
be bent upwardly to facilitate contact therewith by the rotor, as
will be further explained. On the top side of the insulator 36 is
an insulating cover plate 42, which has a recess 43 on the bottom
side in which a common annular conductor 44 is placed. The
conductor 44 has a terminal projection 45 to which electrical
connection can be made.
Positioned within the housing 36 is a rotor structure 48 including
an insulating member 49 having one or more contacts 50 movable
thereby. The member 49 has a slot for receiving the blade 24, with
the operating shaft 14 and the actuating blade 24 cooperating to
form a rotary actuator for the rotor structure 48.
As shown in FIGS. 2 and 4, the movable contact 50 is U-shaped and
has one arm selectively engaging the individual contacts 40 of the
conductors 38 and another arm engaging the common conducting ring
44 (FIG. 2). The movable contact 50 is made of a resilient metal to
provide spring biased engagement with the fixed contacts. It will
be obvious that a plurality of contacts 50 can be positioned in the
recesses provided in rotor 49 to simultaneously bridge a plurality
of contacts 38 to the common conductor 44.
An insulating disc 52 is positioned in the end of the cylindrical
housing member 36 opposite to that engaged by the cover plate 42.
This disc may have projections 54 about the periphery thereof which
mate with recesses 55 in the member 36 to key the same in position.
The disc 52 has a plurality of ridges 56 (FIG. 5) which extend
between the individual contact portions 40 to insure that the
contacts are insulated from each other. The ridges also provide a
recess or well under each contact into which foreign material which
may enter the switch, or which is produced by engagement of the
contacts, can fall to eliminate the possibility of such material
bridging the contacts. Also, the top of the ridge extending between
adjacent contacts 40 may be engaged by the contact 50 as it moves
from one contact portion 40 to another, and can be molded of
material with abrasive therein so that it cleans the engaging
surface of the contact 50. It may be desirable to have a smaller
number of interengaging projections 54 and recesses 55 than shown,
it being only necessary to hold the disc 52 and the housing section
36 in radial alignment so that the ridges 55 are positioned between
the individual contact portions 40. The insulating disc 52 has a
center opening 57 to receive a hub 51 on the rotary insulating
member 49 of rotor structure 48, to hold the rotor structure in
axial alignment.
FIG. 5 shows in more detail the construction of the insulating disc
52 and the ridges 56 thereon. The disc has a central hub portion
53, and the ridges 56 extend from this hub to the edge of the disc
to engage the insulator 36. Actually the ridges 56 continue to the
projections 54 which fit in the recesses 55 in the insulator 36.
The space defined by a pair of adjacent ridges, the hub portion 53
and the inside surface of the insulator 36 forms a well under each
contact into which foreign material can drop, so that this is
removed from the contacts and does not provide a conducting bridge
therebetween. As previously stated, the disc 52 may be molded of
material having abrasive in the portion thereof forming the ridges,
and this acts to clean the surface of contact 50 as this contact
slides thereacross. However, this will produce small conducting
particles which could form bridges between the contacts 40. FIG. 5
shows the contact 40 and the insulator 36 to show the relative
position of the contacts and wells formed by the ridges.
FIG. 6 shows the contact arrangement in more detail, and shows that
a number of contacts 50 may be used on the rotor 48. This figure
also shows that the common conductor 44 may be replaced by a
plurality of flat conductor segments. In the structure shown, six
conductor segments 61, 62, 63, 64, 65 and 66 are used in place of
the single conductor 44. In this structure, a 24 position switch is
illustrated having 24 fixed contacts 40, so that there are four
contacts 40 for each conductor segment 61 to 66. Six movable
contacts 50 are provided in the rotor, one for each segment 61 to
66. The switch structure therefore provides six separate switching
sections, each having four positions in which a different one of
the contacts 40 is connected to one of the contact conductor 61 to
66. For such a switch, the stop pins 34 would be positioned to
allow the stop arm 30 to move through an angle of 60.degree., and
the detent structure 27 would clearly define the four positions in
the 60.degree. segment.
It will be apparent that various arrangements of the movable
contacts and contact segments can be provided to provide desired
switching arrangements. Thus each deck can form a plurality of
separate switch sections, and a plurality of decks can be used. The
switch contact arrangement is extremely flexible and can provide a
large number of simultaneously operated switching section in a very
small switch structure.
In the switch structure shown, the movable contact 50 engages a
ridge 55 as it moves from one contact portion 40 to another, and
breaks the one contact before the next contact is made. It will be
apparent that the contact 50 can be constructed so that it will
simultaneously engage two contact portions, and the first contact
is not broken until after the next contact is made. In such case,
the ridges 55 are constructed so that the contact 50 does not
engage the tops thereof as it moves from one contact portion 40 to
the next.
The switch construction of the invention provides a very compact
rotary switch having 16 or more rotary positions. One or more
switch decks can be provided to thereby provide a large number of
switched connections which can be independent of each other or have
any one of a large number of different relations as may be required
for different applications.
* * * * *