U.S. patent number 3,688,064 [Application Number 05/061,687] was granted by the patent office on 1972-08-29 for vaccuum operated electrical switch with cup shaped diaphragm normally holding contacts closed.
This patent grant is currently assigned to Robertshaw Controls Company. Invention is credited to Ned C. Myers.
United States Patent |
3,688,064 |
Myers |
August 29, 1972 |
VACCUUM OPERATED ELECTRICAL SWITCH WITH CUP SHAPED DIAPHRAGM
NORMALLY HOLDING CONTACTS CLOSED
Abstract
A flexible diaphragm being carried by a support means and
defining an actuating chamber therewith. A switch blade is carried
by the support means and is movable relative thereto, the switch
blade being interconnected to the diaphragm to move in unison
therewith. A fixed contact blade is carried by the support means.
The switch blade has a free end that is arcuate in cross-sectional
configuration so as to be adapted to engage against the contact
blade at the side edge of the switch blade when the diaphragm is in
one position thereof relative to the support means.
Inventors: |
Myers; Ned C. (Elkhart,
IN) |
Assignee: |
Robertshaw Controls Company
(Richmond, VA)
|
Family
ID: |
22037450 |
Appl.
No.: |
05/061,687 |
Filed: |
August 6, 1970 |
Current U.S.
Class: |
200/83N;
200/83B |
Current CPC
Class: |
H01H
35/34 (20130101) |
Current International
Class: |
H01H
35/24 (20060101); H01H 35/34 (20060101); H01h
035/34 () |
Field of
Search: |
;200/83N,83R,83B,83P |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
687,706 |
|
Jan 1930 |
|
FR |
|
1,470,613 |
|
Jan 1967 |
|
FR |
|
Other References
"Fluidic Switch," IBM Technical Disclosure, Vol. 11, No. 8, Jan.
1969 (p. 1021) by M. Krakinowski.
|
Primary Examiner: Smith, Jr.; David
Assistant Examiner: Vanderhye; Robert A.
Claims
1. A vacuum operated electrical switch construction comprising
support means, a flexible diaphragm carried by said support means
and defining a chamber therewith, a switch blade carried by said
support means and being movable relative thereto, said switch blade
being interconnected to said diaphragm to move in unison therewith,
and a fixed contact blade carried by said support means said switch
blade having a free end adapted to engage against said contact
blade when said diaphragm is in one position relative to said
support means, said diaphragm having a natural tendency to move to
a certain position relative to said support means, said switch
blade making contact with said contact blade before said diaphragm
can reach said certain position thereof, said diaphragm having a
natural tendency to assume a cup-shape at said certain position
thereof, said switch blade contacting and deforming into said
cup-shape when in engagement with said contact blade and thereby
preventing said diaphragm from assuming a natural cup-shape thereof
whereby the natural tendency of said diaphragm to assume said
cup-shape assists in normally maintaining
2. A vacuum operated electrical switch construction as set forth in
claim 1 wherein said contact blade has a flat side, said free end
of said switch blade having a straight end edge and being arcuate
so that said end edge is adapted to engage said flat side of said
contact blade when said
3. A vacuum operated electrical switch construction as set forth in
claim 1 wherein said switch blade deforms at an angle into said
cup-shape of said
4. A vacuum operated electrical switch construction as set forth in
claim 1 wherein said support means comprises two housing members
secured together and defining a cavity therebetween, said diaphragm
being disposed in said
5. A vacuum operated electrical switch construction as set forth in
claim 4 wherein said contact blade is secured between engaging
surfaces of said housing members, part of said contact blade
extending into said cavity to be engaged by said switch blade and
another part of said contact blade
6. A vacuum operated electrical switch construction as set forth in
claim 5 wherein one of said housing members has a rivet-like
portion riveted to the other housing member to secure the same
together, said contact blade having an opening passing therethrough
and receiving said rivet-like
7. A vacuum operated electrical switch construction as set forth in
claim 4 wherein said switch blade has the end thereof opposite to
said free end
8. A vacuum operated electrical switch construction as set forth in
claim 7 wherein one of said housing members has a rivet-like
portion riveted to the other housing member to secure the same
together, said switch blade having an opening passing therethrough
and receiving said rivet-like
9. A vacuum operated electrical switch construction as set forth in
claim 8 wherein a terminal has a part thereof secured between said
engaging surfaces of said housing members and another part thereof
extending outwardly from said housing members, said secured part of
said terminal also having an opening passing therethrough and
receiving said rivet-like
10. A vacuum operated electrical switch construction as set forth
in claim 1 wherein said cup-shaped diaphragm has a post means
extending from the closed end thereof, said switch blade being
secured to said post means so
11. A vacuum operated electrical switch construction as set forth
in claim 10 wherein said switch blade has a key-hole slot passing
therethrough and receiving said post means to secure the same
together.
Description
This invention relates to a pneumatically operated electrical
switch construction.
It is well known that various pneumatically operated electrical
switch constructions have been provided wherein a pneumatic signal
directed to an actuating chamber of the electrical switch
construction causes a flexible diaphragm thereof to be moved by the
resulting pressure differential across the same and thereby cause a
switch blade to move relative to a fixed contact means to either
open the circuit or close the circuit as the case may be.
Accordingly, it is a feature of this invention to provide an
improved pneumatically operated electrical switch construction of
the above type.
In particular, one embodiment of the pneumatically operated
electrical switch construction of this invention comprises a
support means carrying a flexible diaphragm defining an actuating
chamber with the support means. A switch blade is carried by the
support means and is movable relative thereto, the switch blade
being interconnected to the diaphragm to move in unison therewith.
A fixed blade is also carried by the support means to cooperate
with the switch blade. The switch blade has a free end that is
arcuate in cross section so that the end edge of the switch blade
is adapted to engage against a flat surface of the contact blade
when the diaphragm is in one position relative to the support
means.
Such pneumatically operated electrical switch construction is made
from a relatively small number of easily assembled parts.
Accordingly, it is an object of this invention to provide an
improved pneumatically operated electrical switch construction
having one or more of the novel features set forth above or
hereinafter shown or described.
Other objects, uses and advantages of this invention are apparent
from a reading of this description which proceeds with reference to
the accompanying drawings forming a part thereof and wherein:
FIG. 1 is a perspective view of the improved pneumatically operated
electrical switch construction of this invention.
FIG. 2 is an enlarged cross-sectional view taken on line 2-2 of
FIG. 1, FIG. 2 illustrating schematically a system utilizing the
pneumatically operated electrical switch construction.
FIG. 3 is an exploded perspective view of the various parts of the
pneumatically operated electrical switch construction of this
invention.
While the various features of this invention are hereinafter
described and illustrated as being particularly adapted to provide
a vacuum operated electrical switch construction, it is to be
understood that the various features of this invention can be
utilized singly or in any combination thereof to provide other
types of fluid operated electrical switch constructions and the
like.
Therefore, this invention is not to be limited to only the
embodiment illustrated in the drawings, because the drawings are
merely utilized to illustrate one of the wide variety of uses of
this invention.
Referring now to FIGS. 1-3, the improved pneumatically operated
electrical switch construction of this invention is generally
indicated by the reference numeral 10 and comprises two housing
members 11 and 12, a cup-shaped flexible diaphragm 13, a resilient
conductive switch blade 14, a terminal member 15 and a contact
member 16 all adapted to be assembled together to provide the
electrical switch construction 10 as illustrated in FIG. 2 in a
simple and effective manner.
The housing member 11 is substantially cup-shaped and is defined by
a substantially flat circular end wall 17 interconnected at its
outer periphery to a substantially cylindrical side wall means 18
having a pair of outwardly directed right angled ears 19 and 30
suitably reinforced by ribbing means 21 as illustrated, the ears 19
and 20 being diametrically opposed to each other and being adjacent
the opened end 22 of the cup-shaped housing member 11. An annular
flange 23 projects inwardly from the end wall 17 of the housing
member 11 and is adapted to have the open end 24 of the cup-shaped
diaphragm member 13 inserted around the same in the manner
illustrated in FIG. 2 so that the flexible diaphragm 13 will
cooperate with the housing member 11 to define an actuating chamber
25 therebetween. The end wall 17 also has an outwardly directed
nipple extension 26 provided with a passage means 27 extending
through the same to interconnect the exterior of the housing member
11 with the actuating chamber 25.
For example, the nipple extension 27 can be interconnected by
suitable conduit means 28 to a vacuum source 29, such as a vacuum
pump or the like, with the conduit means 28 having suitable
selector means 30 disposed therein intermediate the vacuum source
29 and the pneumatically operated electrical switch construction 10
so as to interconnect the vacuum source 29 to the actuating member
25 when the selector means 30 is in one position thereof and to
disconnect the vacuum source 29 from the chamber 25 while
simultaneously interconnecting the atmosphere to the chamber 25
when the selector means 30 is in another position thereof.
The cup-shaped flexible diaphragm 13 has a cylindrical post means
31 extending from the closed end 71 thereof with the post means 31
having an annular groove 32 formed therein adjacent the end wall 71
of the diaphragm 13 for a purpose hereinafter described.
The housing member 12 is substantially flat and circular and is
provided with a pair of ears or legs 33 and 34 extending
diametrically therefrom to respectively cooperate with the ears 19
and 20 of the housing member 11. Flange means 35 are formed on the
outer edges of the housing member 12 so as to define locating
grooves 36 and 37 on the ears 33 and 34 for a purpose hereinafter
described.
The contact member 16 has an opening 38 passing therethrough and
has a substantially flat part 39 for projecting into a cavity 40 of
the construction 10 which is defined between the housing members 11
and 12 when the same are secured together to define a support means
for the electrical switch, the contact member 16 having another
part 41 thereof angularly bent relative to the body of the contact
member 16 to project outwardly from the housing members 11 and 12
and define an external terminal adapted to be interconnected in a
suitable electrical system, such as system 42 in FIG. 2 for a
purpose hereinafter described.
The terminal member 15 also has an opening 43 passing therethrough
and a part 44 angularly bent relative to the body portion of the
terminal member 15 so as to extend outwardly from the housing
members 11 and 12 to be interconnected in the electrical system
42.
The switch blade 15 has one end 45 provided with an opening 46
passing therethrough and has an intermediate part 47 angularly bent
relative to the part 45, the angularly bent part 47 having a
keyhole shaped slot 48 passing therethrough and being provided with
an arcuately bent free end 49 that terminates at an end edge 50
which is disposed at substantially a right angle relative to the
switch blade 15 because of the arcuately bent free end 49 thereof
for a purpose hereinafter described. The post means 31 of the
flexible diaphragm 13 is adapted to be inserted through the large
part 51 of the keyhole opening 48 and thereafter receive the small
part 52 of the slot 48 in the annular groove 32 thereof so as to
fasten the post means 31 to the switch blade 14.
The contact member 16 is adapted to be inserted in the locating
groove 36 of the housing member 12 with a rivet-like portion or
post 53 on the leg 33 of the housing member 12 projecting through
the opening 38 thereof. Similarly, the part 45 of the terminal 15
and the part 45 of the switch blade 14 are adapted to be inserted
in the locating recess 37 of the leg 34 while a rivet-like post
means 54 of the leg 34 passes through the aligned openings 43 and
46 of the terminal 15 and the switch blade 14.
The ears 19 and 20 of the housing member 12 has openings 55 and 56
passing therethrough and respectively receive the post means 53 and
54 of the housing member 12 which are subsequently spun over or
otherwise suitably deformed to form enlarged heads 76 and 57 as
illustrated in FIG. 2 to securely fasten the housing members 11 and
12 together as well as to hold the contact member 16, terminal 15
and switch blade 14 in the assembled arrangement illustrated in
FIG. 2.
Because the flexible diaphragm 13 has a natural tendency to assume
a cup-shape and since the switch blade 14 is angularly bent into
configuration illustrated in FIG. 2, the switch blade 14 has the
end edge 50 urged against the flat surface of the part 39 of the
contact member 16 and is maintained in such engagement by the
natural resiliency of the switch blade 14 as force of the diaphragm
13 tending to assume its normal cup shape whereby excellent
electrical contact is provided between the switch blade 14 and the
contact member 16.
However, when a vacuum is created in the actuating chamber 25 by
having the same interconnected to the vacuum source of pump 29, the
flexible diaphragm 13 is caused to move to the left by the
resulting pressure differential acting across the end wall 71
thereof so that the switch blade 14 moves to the left therewith to
break electrical contact with the contact member 39 until the
actuating chamber 25 again returns to substantially atmospheric
condition.
In this manner, it can be seen that the pneumatically operated
electrical switch construction 10 of this invention can readily be
utilized in the electrical control system 42 to control the same by
having its terminal part 41 interconnected by a lead 58 to one side
59 of a suitable electrical power source 60 that has its other side
61 interconnected by a lead 58 to one side 59 of a suitable
electrical power source 60 that has its other side 61
interconnected by a lead 62 to one side 63 of a load means 64. The
other side 65 of the load means can be interconnected by a lead 66
to the part 44 of the terminal 15 as illustrated in FIG. 2. Thus,
as long as the actuating chamber 25 of the pneumatically operated
electrical switch construction 10 of this invention remains
substantially at an atmospheric condition, electrical current is
adapted to flow through the electrical switch construction 10 since
the switch blade 14 is maintained in electrical contact with the
contact member 16 so that the power source 60 is connected across
the load means 64. However, when the vacuum source 29 is
interconnected by the selector means 30 to the chamber 25, the
flexible diaphragm 13 has its end wall 71 moved to the left to
carry the switch blade 14 thereof away from the contact member 16
and thereby disconnect the power source 60 from across the load
means 64.
Thus, it can be seen that the pneumatically operated electrical
switch construction 10 of this invention can be formed of a
relatively small number of easily assembled parts to function in an
electrical control system in a simple and effective manner.
While the form of the invention now preferred has been disclosed as
required by the patent statutes, other forms may be utilized all
coming within the scope of the claims which follow.
* * * * *