U.S. patent number 3,790,734 [Application Number 05/198,328] was granted by the patent office on 1974-02-05 for alternate action switch with sealing boot giving visual indication of switch position.
This patent grant is currently assigned to Indak Manufacturing Corp.. Invention is credited to Andrew F. Raab, William J. Schaad.
United States Patent |
3,790,734 |
Raab , et al. |
February 5, 1974 |
ALTERNATE ACTION SWITCH WITH SEALING BOOT GIVING VISUAL INDICATION
OF SWITCH POSITION
Abstract
The illustrated switch comprises a push button which is movable
in a casing and is enclosed by a boot made of flexible material. A
latching mechanism is provided in the casing to retain the push
button in a partially depressed position after alternate
depressions of the push button. The mechanism causes the push
button to return to its fully extended position after the
intermediate depressions of the push button. The end of the boot is
caused to follow the movement of the push button, preferably by
means of a disk on the push button which is received in an annular
groove within the boot, or by clamping a flange on the boot between
two disks on the push button. Thus, the length of the boot
indicates the position of the push button. A contactor is connected
to the push button and is movable to different positions
corresponding to the fully extended and partially depressed
positions of the push button. A stem or pin is provided between the
push button and the contactor. The stem also extends through a
latch which is rotatable in successive steps by the operation of
the push button. In alternate positions of the latch, it engages
elements on the casing which retain the push button in its
partially depressed position. Camming elements are provided on the
push button, the latch and the casing to rotate the latch, with the
assistance of a spring, mounted on the stem and acting between the
contactor and the latch. The contactor may engage a set of contacts
in the partially depressed position of the push button. In a
modified construction, a second set of contacts is also provided
for engagement by the contactor in the extended position of the
push button. To provide a make-before-break action, the contactor
may comprise two disks with a spring therebetween, slidably mounted
on a sleeve which in turn is slidably mounted on the pin or
shaft.
Inventors: |
Raab; Andrew F. (Morton Grove,
IL), Schaad; William J. (Winnetka, IL) |
Assignee: |
Indak Manufacturing Corp.
(Northbrook, IL)
|
Family
ID: |
22732922 |
Appl.
No.: |
05/198,328 |
Filed: |
November 12, 1971 |
Related U.S. Patent Documents
|
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
73295 |
Sep 18, 1970 |
|
|
|
|
Current U.S.
Class: |
200/302.2;
200/530; 200/308 |
Current CPC
Class: |
H01H
13/06 (20130101); H01H 13/58 (20130101); H01H
13/14 (20130101) |
Current International
Class: |
H01H
13/06 (20060101); H01H 13/04 (20060101); H01H
13/58 (20060101); H01H 13/14 (20060101); H01H
13/50 (20060101); H01h 013/06 (); H01h 013/56 ();
H01h 009/16 () |
Field of
Search: |
;200/168G,153J,16A,159R,159B,169PB,167R |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
1,515,570 |
|
Aug 1969 |
|
DT |
|
1,127,982 |
|
Apr 1962 |
|
DT |
|
886,759 |
|
Oct 1943 |
|
FR |
|
Primary Examiner: Schaefer; Robert K.
Assistant Examiner: Vanderhye; Robert A.
Attorney, Agent or Firm: Burmeister, Palmatier &
Hamby
Parent Case Text
This application is a continuation-in-part of our copending
application Ser. No. 73,295, filed Sept. 18, 1970 now abandoned.
Claims
1. A push action electrical switch,
comprising a casing having an opening therein,
a push button slidably mounted in said opening,
a contactor movable within said casing and operable by said push
button,
resilient means for biasing said push button outwardly,
a mechanism operable by depression of said push button for
retaining said push button in a partially depressed position after
alternate depressions of said push button,
said mechanism being operative to return said push button to its
fully extended position after the intermediate depressions of said
push button,
said contactor being movable to one position when said push button
is fully extended while being operable to a second position when
said push button is partially depressed,
a flexible boot mounted on said casing and disposed around said
push button to protect said push button from atmospheric
conditions,
said push button being operable by depressing said boot,
and means for causing said boot to follow the movement of said push
button,
said boot thereby having an extended position when said push button
is fully extended and a partially depressed position when said push
button is retained in its partially depressed position,
whereby the position of said boot gives a visual indication of the
position of said push button and the position of said
contactor,
said boot comprising a generally cylindrical side wall and an end
wall connected thereto for following and indicating the position of
said push button,
said push button having an outwardly projecting flange element
thereon,
said boot having an internal annular groove therein for receiving
said flange element to cause said end wall of said boot to follow
and indicate the position of said push button,
said side wall having an outwardly projecting annular convolution
thereon which is operative to bulge outwardly when said push button
is depressed,
said convolution thereby giving a further visual indication of the
position
2. A push action electrical switch,
comprising a casing having an opening therein,
a push button slidably mounted in said opening,
a contactor movable within said casing and operable by said push
button,
resilient means for biasing said push button outwardly,
a mechanism operable by depression of said push button for
retaining said push button in a partially depressed position after
alternate depressions of said push button,
said mechanism being operative to return said push button to its
fully extended position after the intermediate depressions of said
push button,
said contactor being operable to one position when said push button
is fully extended while being operable to a second position when
said push button is partially depressed,
a flexible boot mounted on said casing and disposed around said
push button to protect said push button from atmospheric
conditions,
and means for causing said boot to follow the movement of said push
button,
said boot thereby having an extended position when said push button
is fully extended and a partially depressed position when said push
button is retained in its partially depressed position,
said boot having an annular side wall with an annular portion of
reduced thickness,
said annular portion bulging outwardly to form a pronounced
convolution when said boot is in its partially depressed
position,
whereby said boot gives a visual indication of the position of said
push
3. A switch according to claim 2,
in which said annular sidewall of said boot has an outer surface
which is substantially cylindrical when the boot is extended,
said sidewall having an inner surface which is shaped to provide
said
4. A switch according to claim 2,
in which said annular sidewall of said boot has an outer surface
which is substantially cylindrical when the boot is extended,
said sidewall having an inner surface which is barrel shaped to
provide
5. A push action electrical switch,
comprising a casing having an opening therein,
a push button slidably mounted in said opening,
a contactor movable within said casing and operable by said push
button,
resilient means for biasing said push button outwardly,
a mechanism operable by depression of said push button for
retaining said push button in a partially depressed position after
alternate depressions of said push button,
said mechanism being operative to return said push button to its
fully extended position after the intermediate depressions of said
push button,
said contactor being movable to one position when said push button
is fully extended while being operable to a second position when
said push button is partially depressed,
a flexible boot mounted on said casing and disposed around said
push button to protect said push button from atmospheric
conditions,
and interlocking flange elements on said push button and said boot
for causing said boot to follow the movement of said push
button,
said boot thereby having an extended position when said push button
is fully extended and a partially depressed position when said push
button is retained in its partially depressed position,
said boot having an annular sidewall with means thereon for bulging
outwardly to form a pronounced convolution when said boot is in its
partially depressed position whereby said boot gives a visual
indication of the position of said push button and the position of
said contactor.
6. A switch according to claim 5,
in which said interlocking flange elements comprise an annular
flange projecting inwardly on the upper portion of said boot,
said push button having flange elements for securing said annular
flange
7. A switch according to claim 5,
in which said interlocking flange elements include an annular
flange projecting inwardly on the upper portion of said boot,
and a pair of disks on said push button and clamping said annular
flange
8. A switch according to claim 5,
in which said means on said annular sidewall comprise an outwardly
projecting annular convolution for bulging outwardly to a
pronounced
9. A push action electrical switch,
comprising a casing having an opening therein,
a push button slidably mounted in said opening and movable between
an extended position and a depressed position,
means for temporarily retaining said push button alternately in
said extended position and said depressed position,
a contactor movable within said casing and operable by said push
button,
said contactor being operable to one position when said push button
is in said extended position while being operable to a second
position when said push button is in said depressed position,
a flexible boot mounted on said casing and disposed around said
push button to protect said push button from atmospheric
conditions,
and means for causing said boot to follow the movement of said push
button,
said boot thereby having an extended position when said push button
is in its extended position and a depressed position when said push
button is retained in its depressed position,
said boot having an annular side wall with an annular portion of
reduced thickness,
said annular portion bulging outwardly to form a pronounced
convolution when said boot is in its depressed position,
whereby said boot gives a visual indication of the position of said
push
10. A push action electrical switch,
comprising a casing having an opening therein,
a push button slidably mounted in said opening and movable between
an extended position and a depressed position,
means for temporarily retaining said push button alternately in
said extended position and said depressed position,
a contactor movable within said casing and operable by said push
button,
said contactor being operable to one position when said push button
is in said extended position while being operable to a second
position when said push button is in said depressed position,
a flexible boot mounted on said casing and disposed around said
push button to protect said push button from atmospheric
conditions,
and means for causing said boot to follow the movement of said push
button,
said boot thereby having an extended position when said push button
is in its extended position and a depressed position when said push
button is retained in its depressed position,
said boot having an annular side wall with means thereon for
bulging outwardly to form a pronounced convolution when said boot
is in its depressed position,
whereby said boot gives a visual indication of the position of said
push
11. A push action electrical switch,
comprising a casing having an opening therein,
a push button slidably mounted in said opening and movable between
an extended position and a depressed position,
means for temporarily retaining said push button alternately in
said extended position and said depressed position,
a contactor movable within said casing and operable by said push
button,
said contactor being operable to one position when said push button
is in said extended position while being operable to a second
position when said push button is in said depressed position,
a flexible boot mounted on said casing and disposed around said
push button to protect said push button from atmospheric
conditions,
and means for causing said boot to follow the movement of said push
button,
said boot thereby having an extended position when said push button
is in its extended position and a depressed position when said push
button is retained in its depressed position,
said boot having an annular side wall with an outwardly projecting
annular convolution thereon which is operative to buldge outwardly
when said boot is in its depressed position,
whereby said boot gives a visual indication of the position of said
push button and the position of said contactor.
Description
This invention relates to push action switches which are
particularly well adapted for vehicular switching operations, but
will find many other advantageous uses.
In one embodiment, the switch of the present invention is adapted
to be actuated by depressing a push button to close the switch, and
depressing the push button again to open the switch. In another
embodiment, the switch closes on set of contacts in one position,
and another set of contacts in the other position. The invention is
also applicable to switches having more than two positions.
One object of the present invention is to provide a push action
switch which is effectively sealed against the entry of moisture,
dust and other foreign material which might impair the operation of
the switch.
A further object is to provide a push action switch in which the
external appearance of the switch is visibly different when the
switch is in its different operating positions, so that the
operator can readily observe whether the switch is "on" or
"off."
Another object is to provide a push action switch which is easy to
operate, yet extremely rugged, so that the switch will withstand
long and hard service.
A further object is to provide a push action switch which has a
positive snap action yet is small in size and inexpensive to
manufacture.
Thus, the present invention preferably comprises a push action
switch having a casing with an opening in which the push button or
plunger is slidable. A mechanism is provided in the casing to latch
or otherwise retain the push button in a partially depressed
position, after alternate depressions of the push button. The
intermediate depressions of the push button cause it to return
outwardly to its fully extended position. A contractor within the
casing is moved to two different positions corresponding to the
extended and partially depressed positions of the push button. A
boot made of rubber or other flexible material is mounted around
the push button to exclude moisture, dust and other adverse
atmospheric conditions. The boot is arranged to follow the movement
of the push button so that it is readily possible to determine the
position of the contactor by observing the position of the boot. In
one embodiment, the push button is connected to the boot by means
of a disk or other flange element on the push button. Such flange
element is preferably received in a groove or recess within the
boot. The boot may have an annular convolution which bulges
outwardly when the push button is in its partially depressed
position.
In another embodiment, the boot has an inwardly directed flange
which is clamped between two disks or flanges on the push
button.
The mechanism within the casing includes a latch which is rotated
through successive steps by the successive depressions of the push
button. Camming elements are provided on the latch, and also on the
push button and the casing, to effect such step-wise rotation of
the latch. In alternate positions, the latch is effective to retain
the push button in its partially depressed position.
The push button preferably carries a stem or pin on which the
contactor is mounted. The stem also preferably passes through an
opening in the latch. To assist in the operation of the latch, a
spring is preferably mounted around the stem between the latch and
the contactor. The spring may also provide contact pressure between
the contactor and stationary contacts which are mounted in the
casing.
In one embodiment, the contactor engages one set of contacts in the
depressed position of the push button. In another embodiment, there
is also a second set of contacts, engageable by the contactor in
the extended position of the push button. To provide a
make-before-break action, the contactor may comprise two disks or
other means with a spring therebetween. The disks may be slidably
mounted on a carrier, which in turn is slidably mounted on the
stem.
Further objects, advantages and features of the present invention
will appear from the following description, taken with the
accompanying drawings, in which:
FIG. 1 is an elevation of a push action switch to be described as
an illustrative embodiment of the present invention.
FIG. 2 is a top view of the switch.
FIG. 3 is an elevational section taken generally along the line
3--3 in FIG. 1.
FIG. 4 is an enlarged elevational section, taken generally along
the line 4--4 in FIG. 3, the switch being shown in its "on"
position.
FIG. 5 is a view similar to FIG. 4, but showing the switch in its
"off" position.
FIG. 6 is a bottom view, partly in section along the line 6--6 in
FIG. 4.
FIG. 7 is a view similar to FIGS. 4 and 5, but showing the switch
in its fully depressed position.
FIG. 8 is a transverse section, taken generally along the line 8--8
in FIG. 4, the switch being shown in its "on" position.
FIG. 9 is a transverse section taken generally along the line 9--9
in FIG. 5, the switch being shown in its "off" position.
FIG. 10 is a section taken generally along the line 10--10 in FIG.
4, with the latch removed to avoid obscuring details of the push
button.
FIG. 11 is a disassembled or exploded perspective view of the
switch.
FIG. 12 is a central longitudinal section taken through the casing
of the switch.
FIG. 13 is a bottom view of the casing, taken as indicated by the
lines 13--13 in FIGS. 11 and 12.
FIG. 14 is an elevation of the push button.
FIG. 15 is a bottom view of the push button taken generally as
indicated by the lines 15--15 in FIG. 11 and 14.
FIG. 16 is an elevation of the latch.
FIG. 17 is a bottom view of the latch, taken generally as indicated
by the lines 17--17 in FIG. 11 and 16.
FIG. 18 is a fragmentary disgrammatic developed elevation to show
the action of the camming elements which cause rotation of the
latch, the switch being shown in its "on" position.
FIG. 19 is a fragmentary section taken generally along the line
19--19 in FIG. 18.
FIG. 20 is a fragmentary section taken along the line 20--20 in
FIG. 18.
FIG. 21 is a fragmentary section, taken generally along the line
21--21 in FIG. 18.
FIG. 22 is a view similar to FIG. 18, but showing the switch with
the push button depressed.
FIG. 23 is another view similar to FIGS. 18 and 22, but showing the
switch with the push button latched in the "off" position of the
switch.
FIG. 24 is a fragmentary section taken generally along the line
24--24 in FIG. 23.
FIG. 25 is an enlarged longitudinal section showing a modified
switch to be described as another illustrative embodiment of the
present invention, the push button of the switch being shown in its
fully extended position.
FIG. 26 is a view similar to FIG. 25, but showing a further
modification, the push button being shown in its fully depressed
position.
FIG. 27 is a view similar to FIG. 26, but with the longitudinal
section taken at right angles to the section of FIG. 26, the switch
being shown with the push button latched in its partially depressed
position.
FIG. 28 is a cross-section taken generally along the lines 28--28
in FIG. 26
FIG. 29 is a longitudinal section showing another modified switch
construction.
FIG. 30 is a cross-section taken along the line 30--30 in FIG.
29.
It will be seen that FIGS. 1-24 illustrate a push action electrical
switch 30 adapted to be operated between "on" and "off" positions.
While the illustrated switch will find many applications, it was
developed particularly for use as an ignition kill switch for a
snowmobile. In this particular application, the switch short
circuits the ignition circuit when the switch is in the "off"
position. This has the effect of stopping the engine of the
vehicle. Thus, the switch is closed in its "off" position and open
in its "on" position.
The illustrated switch 30 comprises a casing or body 32 which may
be made of a tough resinous plastic material, or any other suitable
material. A push button or plunger 34 is slidable in an opening 36,
formed in the casing 32.
A contactor 38 is movably mounted within the casing 32 and is
adapted to engage stationary contact means, illustrated as
comprising a pair of contact points 40 and 42. In this case, the
contact points are formed as the heads of rivets 44 and 46,
extending through an insulating disk or other member 48, closing
one side of the casing 32. The insulating disk 48 is preferably
made of a suitable plastic material. It may be welded or otherwise
secured to the plastic material of the casing 32.
As shown, terminals or lugs 50 and 52 are mounted on rivets 44 and
46. Insulated leads 54 and 56 are connected to the terminals 50 and
52.
The push button 34 is enclosed within a boot 60, made of a flexible
material, such as natural or synthetic rubber. The illustrated boot
60 has an end wall 62 and a generally cylindrical side wall 64. The
push button 34 is operated by pressing upon the end wall 62 of the
boot 60. It will be understood that the boot 60 is effective to
exclude moisture, dust and other adverse atmospheric conditions
from the switch. The lower end of the boot 60 is clamped against
the casing 32 so as to form a seal therewith. As shown, the lower
end of the boot 60 is formed with an outwardly projecting flange 66
which is clamped against an outwardly projecting flange 68 on the
casing 32. The clamping action is achieved by suitable means,
illustrated as a ring 70, made of metal or other suitable material.
The ring 70 has a radial flange 72 which engages the flange 66, and
a generally cylindrical flange 74 which extends around the flanges
66 and 68. As shown to best advantage in FIG. 6, ears or tabs 76
are bent from the flange 74, under the flange 68 on the casing
32.
In this case, the ring 70 is formed in one piece with a mounting
bracket or clamp 78, adapted to be used to secure the switch 30 to
a handle bar 80 or the like. For use on a snowmobile, it is
advantageous to mount the switch 30 on the handle bar 80 of the
vehicle, so that the switch will be readily accessible for quick
operation. In the operation of a snowmobile, it sometimes happens
that the throttle of the engine will freeze or stick in its open
position. If this happens when the engine is started, the vehicle
may run away due to the excessive speed of the engine, which
actuates the automatic clutch often found on such vehicles. If the
operator has dismounted from the vehicle to start the engine, the
vehicle may run away from him unless some control device is
provided for quickly stopping the engine. The illustrated switch
may be employed very advantageously as such a control device.
The illustrated clamp 78 is in the form of a split band having legs
82 and 84, together with a screw 86 for tightening the clamp. To
engage the handle bar 82, the casing 32 is formed with a skirt
portion 88 having a cylindrically curved seat 90. The skirt 88,
together with the handle bar 80, forms an enclosure for the rivets
44, the insulating terminal member 48, and the terminals 50 and 52,
so that these components are protected from the weather. A small
vent hole 92 is preferably formed in the insulating member 48 to
prevent any build up of pressure within the casing 32. The vent
hole 92 is in a protected position and is normally concealed by the
skirt 88 and the handle bar 80.
In the illustrated switch 30, the push button 34 is fully extended
when the switch is "on," as illustrated in FIG. 4. The push button
34 is latched in a partially depressed position when the switch is
"off," as shown in FIG. 5. The boot 60 is constructed and arranged
so that it follows and indicates the position of the push button
34. Thus, the "on" and "off" positions of the boot 60 are indicated
in FIGS. 1, 4, 5, and 7. FIGS. 1 and 7 also indicate the maximum
depression or travel of the boot 60. The switch is shown in its
fully depressed position in FIG. 7.
As illustrated, the boot 60 is connected to the push button 34, so
as to follow the movement thereof, by means of a flange element 94
mounted on the push button 34. An annular groove or recess 96 is
formed within the boot 60 to receive the flange element 94. As
shown, the flange element 94 takes the form of a disk, made of
metal or some other suitable material. An axial pin or rivet 98 is
preferably employed to secure the disk 94 to the push button
34.
It will be understood that the flange element 94 and the groove 96
provide interlocking elements on the push button 34 and the boot
60. The groove 96 is immediately adjacent the end wall 62 of the
boot so that the flange element 94 engages the end wall.
The flange element 94 also engages one end of a return spring 100
which may assume various forms but is illustrated as a compression
coil spring, acting between the flange element 94 and the casing
32. An annular groove or seat 102 is preferably formed in the
casing 32 to receive the lower end of the return spring 100.
The return spring 100 is concealed within the flexible boot 60. It
will be seen from FIGS. 4 and 5 that the cylindrical side wall 64
of the boot 60 is formed with an outwardly bulging convolution or
pleat 104 which is annular in shape. The convolution 104 bulges
outwardly to a greater extent when the end of the boot 60 is pushed
inwardly to depress the push button 34. Thus, the convolution 104
bulges outwardly to a greater extent when the push button 34 is in
its partially depressed or "off" position, as shown in FIG. 5, than
when the push button 34 is in its fully extended or "on" position,
as shown in FIG. 4. Thus, the bulging of the conventional 104
provides an additional visual indication as to the position of the
push button.
A latch 106 is mounted within the casing 32 to hold the push button
34 in its "off" position, as shown in FIG. 5. The construction of
the latch 106 is shown to good advantage in FIG. 11. In this case,
the latch 106 is generally cylindrical in shape and is rotatable
and slidable within the push button 34.
In the illustrated construction, the pin or rivet 98 is employed to
maintain the push button 34 and the latch 106 in their assembled
relation. The contactor 38 is also mounted on the pin 98. A
compression coil spring 108 is mounted around the pin 98 between
the contactor 38 and the latch 106.
It will be seen from FIG. 11 that the pin 98 has an enlarged
cylindrical portion 110 which extends through a central opening 112
in the contactor 38. Thus, the contactor 38 is rotatable and
slidable on the enlarged portion 110. A head 114 is formed on the
lower end of the pin 98 to act as a stop for limiting the downward
movement of the contactor 38. While the illustrated contactor 38 is
generally in the form of a flat disk, made of copper or some other
conductive material, the central portion of the contactor is dished
or formed upwardly to provide a downwardly facing recess 116 for
the head 114. The spring 108 presses the contactor 38 downwardly so
that it engages the head 114 when the switch is in its "on"
position, as shown in FIG. 4.
The illustrated pin 98 has a reduced intermediate portion 118 for
receiving and guiding the latch 106, which has an end wall 120 with
an opening 122 therein, adapted to be slidably and rotatably
mounted around the reduced portion 118. Below the end wall 120, the
latch 106 has an enlarged opening 124 which affords clearance for
the spring 108 and the enlarged portion 110 of the pin 98. A
shoulder 126 is formed on the pin 98 between intermediate portion
118 and the enlarged portion 110, to limit the downward movement of
the latch 106 relative to the push button 34.
It will be seen that the pin 98 has a reduced end portion 128
adapted to receive the push button 34 which has an end wall 130
with an opening 132 therein, adapted to fit around the reduced end
portion 128. The flange element or disk 94 has a central opening
134 which is also adapted to receive the reduced end portion 128 of
the pin 98. As shown in FIGS. 4 and 5, the disk 94 is retained
against the end of the push button 34 by upsetting the reduced end
portion 128, as indicated at 136. The disk 94 and the end wall 130
of the push button 34 are clamped or retained between the upset
portion 136 and a shoulder 138, formed on the pin 98 between the
intermediate portion 118 and the reduced end portion 128.
When the push button 34 is depressed, the contactor 38 is moved
downwardly, because of its mounting on the pin 98. The contactor 38
engages the contact points 40 and 42, as shown in FIG. 5. Further
downward movement of the push button 34 causes the enlarged portion
110 of the pin 98 to move downwardly through the opening 112 in the
contactor 38. The spring 108 pushes the contactor 38 downwardly,
and thus provides contact pressure between the contactor 38 and the
contact points 40 and 42. The opening 112 in the contactor 38 is
somewhat larger in diameter than the enlarged portion 110 of the
pin 98, so that the contactor 38 is able to rock slightly relative
to the pin, so that the contact pressure between the contactor 38
and the two contact points 40 and 42 will be equalized.
The push button 34 can be depressed an appreciable distance beyond
the "off" position, shown in FIG. 5. The fully depressed position
of the push button 34 is shown in FIG. 7, in which the disk 94
engages the upper end of the casing 32, to limit the downward
movement of the push button. In this position, the head 114 of the
pin 98 projects downwardly into a downwardly offset central portion
140 of the insulating disk or wall 48, on which the contact points
40 and 42 are mounted.
Camming means are preferably provided on the casing 32, the push
button 34, and the latch 106 to actuate the latch, so that the push
button will be retained in its partially depressed or "on"
position, when the push button is depressed once, while being
released to its fully extended or "off" position, when the push
button is depressed a second time. In the illustrated construction,
such camming means comprise a plurality of teeth 150 on the latch
106, a plurality of teeth 152 on the push button 34, and a
plurality of pairs of splines or ribs 154 and 156, projecting
inwardly from the casing 32, as illustrated to advantage in FIG.
11, and also in FIGS. 18-24. The teeth 150 project outwardly from
the latch 106 and are slidably and rotatably received within a bore
or opening 158 formed in the casing 32. The latch 106 has an
enlarged cylindrical portion 160 which is rotatably and slidably
received within an opening 162 in the push button 34.
In this case, there are six teeth 150 on the latch 106, 12 teeth
152 on the push button 34, and three pairs of the splines 154 and
156 projecting inwardly from the bore 158 in the casing 32.
However, the number of teeth and splines can be varied.
A step 164 is disposed between each pair of splines 154 and 156.
The step 164 projects inwardly from the bore 158, as will be
evident from FIGS. 20 and 21. The step 164 forms the bottom of a
groove 166 between the splines 154 and 156.
For clarity of explanation, the teeth 150 will be designated 150a,
b, c and d in FIGS. 18, 22 and 23, which are developed or flattened
views looking at the inside of the casing 32. Similarly, the teeth
152 on the push button 34 will be designated 152a-i. The splines
154 and 156 will be designated 154a, b and c and 156a, b and c.
Likewise, the steps and grooves 164 and 166 will be designated
164a, b and c and 166a, b and c.
It will be seen from FIG. 18 that the teeth 152c are 152g are
slidably received in the grooves 166a and b. In this way, rotation
of the push button 34 is prevented, so that the push button is
slidable but not rotatable within the casing 32. The teeth 152c and
g are slidable along the steps 164a and b.
FIG. 18 represents the fully extended or "on" position of the push
button 34. In this position, the teeth 152 engage the end wall 168
of the casing 32. It will be understood that the return spring 100
biases the push button 34 toward its fully extended position. In
FIG. 18, the splines 154a and 156a are received between the teeth
150a and b on the latch 106. Similarly, the splines 154b and 156b
are received between the teeth 150c and d. The teeth 150a, b, c and
d on the latch engage the teeth 152b, d, f and h on the push button
34. The spring 108 biases the latch 106 outwardly so that its teeth
150 engage the aligned teeth 152 on the push button.
The latch teeth 150 have inclined camming surfaces 170 which are
engageable with inclined camming surfaces 172 on the push button
teeth 152. The camming surfaces 170 and 172 are inclined relative
to the axis of the push button 34. Because of the force exerted by
the spring 108, the camming surfaces 170 and 172 tend to cause
rotation of the latch 106 to the right, as illustrated in FIG. 6.
However, the splines 154 and 156 prevent such rotation by meshing
with the teeth 150.
When the push button 34 is depressed, the push button teeth 152
move the latch teeth 150 downwardly, as shown in FIG. 22, until the
latch teeth 150 escape from the splines 154, with the result that
the teeth 150 slip or rotate to the right due to the camming action
between the inclined surfaces 170 and 172. The latch 106 is thereby
rotated through a small step until the latch tooth 150a engages the
side of the next push button tooth 152c, as shown in FIG. 22.
Similarly, the teeth 150b, c and d move against the push button
teeth 152e, g and i. It will be seen that the latch teeth 150a and
c are aligned with the splines 154a and b.
Thus, when the push button 34 is released, the latch teeth 150
follow the push button teeth 152 upwardly until the camming
surfaces 170 on the latch teeth 150a and c engage inclined camming
surfaces 174 on the splines 154a and b. These camming surfaces 174
also extend along the steps 164a and b. The camming surfaces 174
arrest the return movement of the latch teeth 150. Due to the force
exerted by the return spring 100, the camming surfaces 170 and 174
cause additional rotation or slipping movement of the teeth 150 to
the right, until the teeth 150a and c engage the sides of the
splines 156a and b, as shown in FIG. 23. This represents the
partially depressed or "off"]position of the switch. The engagement
of the latch teeth 150 with the camming surfaces 174 prevents the
return movement of the latch 106. Due to the very limited lost
motion between the push button 34 and the latch 106, the return
movement of the push button is also prevented. The lost motion
between the latch 106 and the push button 34 is determined by the
length of the intermediate portion 118 of the pin 98, the latch
being slidable to a limited extent along the intermediate portion
118.
When the push button 34 is again depressed, the splines 156 prevet
rotation of the latch 106 until the teeth 150 are moved downwardly
to a sufficient extent to escape from the splines 156, whereupon
the camming action between the surfaces 170 and 172 causes the
latch teeth 150 to slip or rotate to the right. The camming
surfaces 170 on the latch teeth 150a and c engage camming surfaces
176 on the splines 156a and b. The camming action between the
surfaces 170 and 176 causes additional rotation or slipping
movement of the latch teeth 150 to the right until the camming
surfaces 170 escape from the camming surfaces 176, whereupon the
latch teeth 150 are returned upwardly with the splines 154 and 156
therebetween, to a position corresponding to that shown in FIG. 18,
but with the latch displaced or rotated through one full step to
the right, so that the latch tooth 150a is moved to the position
occupied by the tooth 150b in FIG. 18.
It may be helpful to summarize the operation briefly. In FIGS. 4
and 18, the push action switch is shown in its fully extended or
"on" position. When the push button 34 is depressed by pushing on
the end wall 62 of the flexible boot 60, the latch 106 travels
downwardly without rotating, until the latch teeth 150a and c are
below the ends of the splines 154a and b, whereupon the camming
action between the inclined surfaces 170 and 172 on the latch teeth
150 and the push button teeth 152 causes the latch 106 to rotate
through a partial step to the right, until the latch teeth 150 are
arrested by the adjacent push button teeth 152 as shown in FIG. 23.
When the push button 34 is released, the camming surfaces 170 on
the latch teeth 150 engage the camming surfaces 174 on the casing
32. Such engagement causes the latch teeth 150 to slip to the right
so that the latch 106 is rotated until the latch teeth engage the
splines 156, as shown in FIG. 23. The return of the latch 106 is
thus prevented. The push button 34 is also retained in a partially
depressed position, due to the very limited lost motion between the
push button and the latch. In this partially depressed position,
the contactor 38 is pressed against the contacts 40 and 42 by the
spring 108.
When the push button 34 is again depressed by pushing on the end
wall 62 of the boot 60, the latch teeth 150 escape from the splines
156, whereupon the camming action between the inclined surfaces 170
and 172 causes additional rotation or slipping movement of the
latch teeth 150 to the right until the camming surfaces 170 engage
the inclined surfaces 176 on the splines 156. The resultant camming
action rotates the latch 106 until the splines 154 and 156 enter
the spaces between the latch teeth 150, whereupon the latch 106 and
the push button 34 are returned to their fully extended positions,
as shown in FIGS. 4 and 18.
It will be appreciated that the push action switch is extremely
rugged and virtually indestructible. The switch can be operated
very quickly by striking the end of the boot 60 with the operator's
fist or hand. The operator can easily operate the switch even
though he is wearing heavy mittens or gloves. Thus, the switch is
very well suited for use as an emergency kill switch for stopping
the engine on a snowmobile to prevent the machine from running away
if the throttle freezes or sticks in the "open" position when the
engine is started.
The position and appearance of the boot 60 indicate the position of
the switch. When the boot 60 is extended, the switch is "on." When
the convolution 104 on the boot 60 is prominent, as shown in FIG.
5, and the boot is shortened, the switch is in its "off"
position.
In the illustrated switch, the contactor is mounted on the push
button or plunger. However, it will be understood that the
contactor can be mounted on the latch. While the illustrated
contactor is of the linear, movable type, it can be of the rotary
type, particularly when the contactor is mounted on the latch,
which is caused to rotate, as an incident to its latching
function.
While the illustrated switch produces a closed circuit in its
depressed position, the switch can be arranged to produce a closed
circuit in its extended position.
FIG. 25 illustrates a modified push action switch 230 which is
similar in many respects to the switch 30 already described. Many
of the components of the switch 230 are similar to those of the
switch 30. To avoid repetitious description, corresponding
components of the switch 230 will be given reference characters
which are increased by 200, with respect to the corresponding
components of the switch 30. In this way, the previous description
of the switch 30 can readily be applied to the switch 230. The
corresponding components of the switches 230 and 30 may be the same
in construction, except as otherwise specified in the following
description, which can thus be confined for the most part to the
differences between the switch 230 and the previously described
switch 30 of FIGS. 1-24.
Instead of having an "off" position and an "on" position, the
switch 230 has two "on" positions, in which two different circuits
are closed. The switch 230 will find many applications. For
example, the switch may be employed to close the circuits to the
low and high beam lamps or filaments of an automotive head lamp
arrangement. Many other applications of the switch will be evident
to those skilled in the art.
The switch 230 of FIG. 25 comprises a modified casing or body 232,
as before. A push button or plunger 234 is slidable in an opening
236, formed in the casing 232.
While the switch 230 might have a single contactor, as before, it
is preferred to provide two contactors 238a and b. In the latched
or paritally depressed position of the push button 234, as shown in
FIG. 27, the first contactor 238a engages contact points 240a and
242a. In the fully extended position of the push button 234, the
second contactor 238b is moved into engagement with fixed contacts
240b and 242b. The contact points 240a and 242a are formed as the
heads of rivets 244a and 246a, extending through an insulating
member 248, welded or otherwise secured to the casing 232.
The other fixed contacts 240b and 242b may be formed in various
ways. As shown in FIG. 25, the fixed contacts 240b and 242b are in
the form of flanges or heads on shouldered rivets 244b and 246b. It
will be seen that the flange contacts 240b and 242b are spaced a
substantial distance above the insulating member 248. When the push
button 234 is fully extended, as shown in FIG. 25, the second
contactor 238b engages the undersides of the flanges 240b and
242b.
As shown in FIG. 27, terminals 250a and 252a are mounted on the
rivets 244a and 246a. It will be seen from FIG. 25 that terminals
250b and 252b are mounted on the rivets 244b and 246b. If desired,
one of the terminals, such as the terminal 250b, may be in the form
of a strap connected to another rivet, such as the rivet 244a. In
this way, two of the rivets will be connected in common, as to a
battery circuit, for example. Further details of the contactors and
contacts will be described presently.
The push button 234 is enclosed within a flexible boot 260. Instead
of having a solid end wall, the boot 260 has an annular flange 262,
projecting inwardly from a cylindrical sidewall 264. The lower end
of the boot 260 is formed with an outwardly projecting flange 266
which is clamped against an outwardly projecting flange 268 on the
casing 232. The clamping action is achieved by a clamping member
270, preferably made of metal, and formed with a radial flange 272
and a skirt 274. The clamping member 270 may be secured to the
casing 232 by means of ears or tabs, as previously described.
The illustrated flange 268 on the casing 232 is formed with
mounting holes 275. Corresponding holes are formed in the clamping
member 270.
As before, the boot 260 follows the movement of the push button 234
and indicates the position of the push button, whether it is in its
extended position of FIG. 25, or its latched, partially depressed
position of FIG. 27. Thus, the boot 260 is connected to the push
button 234 so as to follow the movement thereof. This may be
achieved by means of flange elements 294a and b, mounted on the
push button 234. In the construction of FIG. 25, the inwardly
directed flange 262 on the boot 260 is clamped or retained between
the flange elements 294a and b. As before, the flange element 294a
preferably takes the form of a metal disk, mounted on an axial pin
or rivet 298, extending through corresponding openings in the push
button 234 and the disk 294a. The other flange element 294b may
also be in the general form of a disk, appertured to receive the
pin 298. The disk 294b may be made of a resinous plastic or some
other suitable material.
As shown, the flange element or disk 294b has a recduced lower
portion 299a which extends through the internal opening 299b formed
by the flange 262 on the boot 260. The reduced portion 299a engages
the disk 294a.
As before, a return spring 300 is compressed between the flange
element 294a and the body or casing 232. The spring 300 is disposed
within the flexible boot 260.
Instead of having a pronounced initial pleat or convolution, as
previously described, the sidewall 254 of the boot 260 is closely
cylindrical on its outer side when the boot 260 is fully extended,
as shown in FIG. 25. However, the sidewall 264 has an inner surface
304a which is barrel shaped, so that the thickness of the sidewall
264 is reduced around the central portion thereof. Thus, when the
push button 234 and the boot 260 are depressed, as shown in FIGS.
26 and 27, the central portion of the sidewall 264 bulges outwardly
to form a pronounced annular convolution 304b. In this way, the
appearance of the convolution 304b makes it clearly evident that
the push button is depressed. As before, a latch 306 is mounted
within the casing 232 to hold the push button 234 in its partially
depressed position, as shown in FIG. 27. The latch 306 is the some
in construction and operation as previously described with
reference to the latch 106. The cooperative elements on the push
button 234 and the casing 232 are also the same as described with
reference to the corresponding elements of FIGS. 1-24.
As before, the latch 306 is rotatably and slidably mounted on the
pin or rivet 298, which also carries the contactors 238a and b.
However, in this case, it is preferred to mount the contactors 238a
and b on a sleeve 307a, which is slidably mounted on the enlarged
portion 310 of the pin 298. The illustrated sleeve 307a is in the
form of an eyelet having heads or flanges 307b and 307c at both
ends. The contactors 238a and b are preferably in the form of
appertured disks which are slidably mounted on the sleeve 307a. A
spring 307d is preferably compressed between the contactors 238a
and b, so that the contactors are biased towards the flanges 307b
and c. A compression coil spring 308 is preferably mounted around
the pin 298 between the sleeve 307a and the latch 306.
As shown in FIG. 25, the lower end of the pin 298 is preferably
formed with a cylindrical head 314 which retains the sleeve 307a
and also is slidably piloted in an opening 315a, formed in a
projecting portion 315b of the insulating member 248. In this way,
the pin 298 is guided for axial sliding movement. This guiding
action maintains the contactors 238a and b in its desired
relationship to the fixed contacts 240a, 242a, 240b and 242b.
The latch 306 is guided on the pin 298 in the same manner as
described with reference to the pin 98. As before, the pin 298 has
an upset end portion or head 336, which, in this case, is recessed
into a counter-bore 337 formed in the disk 294b. If desired, the
counter-bore 337 may be filled with an insulating material so that
the head 336 will not be exposed.
As before, camming means are preferably provided on the casing 232,
the push button 234 and the latch 306 to actuate the latch so that
the push button will be retained in its partially depressed
position, when the push button is depressed once, and will be
released to its fully extended position, when the push button is
depressed a second time. Such camming means may be the same as
described in connection with the switch 30 of FIGS. 1-24.
In FIG. 25, the push button 234 and the flexible boot 160 are fully
extended. In this position, the counter disk 238b engages the fixed
contact flanges 240b and 242b on the shouldered rivets 240b and
246b. Thus, the circuit between these rivets is completed. This
circuit may be employed to energize the high beam filament or
filaments in an automotive head lamp circuit. The switch is
particularly advantageous for use in the head lamp circuit of a
snowmobile or the like, because the switch may readily be mounted
on the handle bar of such a vehicle. The operator of the vehicle
can easily operate the switch with one thumb or finger while he
retains his grip on the handle bar.
When the contactor 238b engages the contact flanges 240b and 242b,
the contactor is moved away from the flange 307c on the sleeve
307a, so that the spring 307d presses the contactor against the
contact flanges. This arrangement assures firm and uniform contact
pressure between the contactor 238b and the contact flanges 240b
and 242b. The spring 307d is preferably of the conical compression
type so that it can be compressed fully between the contactors 238a
and 238b, as needed. The axial opening in the contactor 238b
affords sufficient clearance around eyelet sleeve 307a to provide
for a considerable degree of rocking movement of the contactor. In
this way, the contactor 238b can be rocked by the spring 307d so as
to equalize the contact pressure between the contactor 238b and the
contact flanges 240b and 242b. In the extended position of FIG. 25,
the spring 308 presses the eyelet sleeve 307a against the enlarged
head 314.
The provision of the dual slidable contactors 238a and b, with the
spring 307d therebetween, results in a make-before-break action
when the push button 234 and the boot 260 are depressed. Such
depression causes the pin 298 to be moved downwardly. The enlarged
head 314 on the pin is slidably guided in the opening 315a. The
spring 308 causes the eyelet sleeve 307a to be moved downwardly
with the pin 298. However, the upper contactor 238b continues to be
held against the fixed contact flanges 240b and 242b. The lower
contactor 238a moves downwardly along with the sleeve 307a, until
the lower contactor engages the fixed contacts 240a and 242a,
somewhat as shown in FIG. 27. The lower contactor 238a makes
contact with the fixed contacts 240a and 242a before the upper
contactor 238b breaks contact with the fixed contact flanges 240b
and 242b. This make-before-break action is highly advantageous in
that it provides momentary overlapping in the energization of the
two circuits controlled by the switch. When the switch is used in a
head lamp circuit to energize the high and low beam filaments,
there is a momentary interval of overlapping in which both the high
and low beam filaments are energized. This mode of operation
insures that there will be no momentary black-out of the lights
when the switch is operated. Moreover, the head lamp load is kept
on the energizing circuit at all times. This factor is particularly
advantageous when the switch is used on a snowmobile or other
vehicle in which the head lamp and tail lamp are energized directly
from an alternator without any battery to stabilize the voltage.
The overlapping in the energization of the high and low beam
filaments insures that there will be no interval in which the head
lamp load is not imposed upon the alternator. If there were any
such interval of no head lamp load, the voltage would tend to rise
to such an extent that the tail lamp might be burned out. The
make-before-break action avoids any such problem.
FIG. 26 shows the fully depressed position of the push button 234
and the boot 260. It will be seen that the pin 298 slides
downwardly through the eyelet sleeve 307a, while the spring 308 is
compressed. The spring 307d is also compressed between the
contactors 238a and b. Thus, the engagement between the contactors
and the fixed contacts does not interfere with the depression of
the push button 234 and the boot 260
FIG. 27 shows the latched position of the push button 234 in which
it is held in a partically depressed position, in the manner
described with reference to the switch 30. It will be seen that the
lower contactor 238a engages the fixed contacts 240a and 242a,
while the upper contactor 238b engages the upper flange 307c on the
eyelet sleeve 307a. The spring 307d is compressed between the
contactors 238a and b and is effective to press the lower contactor
238a against the contact points 240a and 242a. The axial opening in
the contactor 238a provides clearance around the eyelet sleeve 307a
so that the contactor can be rocked sufficiently by the spring 307d
to equalize the contact pressure between the contactor and the
fixed contacts 240a and 242a. The lower contactor 238a is displaced
upwardly from the lower flange 307b on the eyelet sleeve 307a.
When the push button 234 is again depressed, the latch 306 is
released, so that the push button is allowed to return to its fully
extended position when the operating pressure on the push button is
removed. As the push button 234 travels upwardly, the enlarged head
314 on the pin 298 picks up the eyelet sleeve 307a and causes it to
move upwardly. The upper contactor 238b is moved upwardly with the
eyelet sleeve 307a until the upper contactor makes contact with the
fixed contact flanges 240b and 242b, somewhat as shown in FIG. 25.
Shortly thereafter, the lower flange 307b on the eyelet sleeve 307a
picks up the lower contactor 238b and moves it upwardly, out of
contact with the fixed contacts 240a and 242a. Thus, there is also
a make-before-break action during the return movement of the push
button 234 and the boot 260.
When the push button 234 is fully extended, as shown in FIG. 25,
the sidewall 264 of the boot 260 is substantially cylindrical. When
the push button 234 is latched in its partially depressed position,
as shown in FIG. 27, the convolution 304b is quite pronounced in
the sidewall 264 of the boot 260. This action gives a definite
indication that the push button switch is in its depressed
position.
The flange member or disk 294b on the upper end of the push button
234 may be marked with words or symbols to identify the switch and
to indicate its function. Thus, for example, the word DIM may be
applied to the disk 294b when the switch is to be used to control
the high and low beam filaments of the head lamps. The disk 294b
may be of various colors to identify the switch.
In nearly all respects FIGS. 26, 27 and 28 correspond with FIG. 25,
but FIGS. 26 and 28 show a modified contact construction in which
the fixed contact flanges 240b and 242b of FIG. 25 are replaced by
contact flanges 440b and 442b, preferably formed on Z-shaped
contact members 440c and 442c, which may be made of sheet metal.
The Z-shaped contact members 440c and 442c are secured to the
insulating member 248 by rivets 444b and 446b. The Z-shaped contact
members 440c and 442c replace the shouldered rivets 244b and 246b
of FIG. 25. It will be seen that the rivets 444b and 446b of FIG.
26 are completely away from the lower contactor 238a.
FIG. 28 illustrates the modified contact construction of FIG. 26.
FIG. 27 corresponds to both FIGS. 25 and 26, inasmuch as the
section plane of FIG. 27 is taken through the fixed contacts 240a
and 242a, which are the same in both the switch 230 of FIG. 25 and
the modified version of FIG. 26.
FIGS. 29 and 30 illustrate another modified switch 530 which is the
same in most respects as the switch 230 of FIG. 25. However, the
switch 530 has a casing 532 of modified shape. A cover member 532a
is provided to close the lower end of the casing, so that all of
the contact rivets and terminals are fully enclosed and insulated.
In this way, any possibility of a short-circuit is obviated. The
cover 532a may be suitably secured to the casing 532 by ultrasonic
welding or otherwise.
The casing 532 and the cover 532a have radially projecting stub
members 532c and 532d with openings 532e therein through which
connecting leads 532f are brought out. The leads 532f may be
tightly sealed in the openings 532e to exclude moisture.
In the modified switch 530 of FIG. 29, the flat contactor disks
238a and b of FIG. 25 are replaced by dished contactor disks 538a
and b. The dish-shape of the contactors 538a and b makes it
possible to provide a more compact switch construction utilizing a
shorter inner pin 598 in place of the pin 298. As before, the
conical spring 307d is compressed between the contactors 538a and
b. The eyelet sleeve 307a and the spring 308 are substantially the
same as before.
The switch 530 utilizes fixed contacts 540a and 542a, which take
the form of rounded heads on rivets 544a and 546a. The contacts
540a and 542a are engaged by the lower contactor 538a when the push
button 234 is depressed. When the push button 234 is extended, the
upper contactor 538b engages fixed contacts 540b and 542b, which
are preferably in the form of flanges formed on sheet metal contact
members 540c and 542c. It will be seen that the contact members
540c and 542c are different in shape from the sheet metal contact
members 440c and 442c of FIG. 26. In this case, the contact member
540c is secured to the insulating member 548 by the rivet 546a, on
which the contact point 542a is formed. Thus, the rivet 546a serves
as a common terminal for the contact point 542a and the contact
member 540c, on which the contact flange 540b is formed. A separate
rivet 546b may be employed to secure the other contact member 542c
to the insulating member 548.
When the push button 234 is extended, as shown in FIG. 29, the
upper contact disk 538b engages the overhanging contact flanges
540b and 542b. The spring 307d is compressed, as before, between
the contactors 538a and b, to provide contact pressure between the
contactor 538b and the contact flanges 540b and 542b. The action of
the contactors 538a and b is the same as described with reference
to the contactors 238a and b of FIG. 25.
When the push button 234 of FIG. 29 is depressed, the lower
contactor 538a engages the fixed contact points 540a and 542a. Such
engagement occurs before the contact is broken between the
contactor 538b and the contact flanges 540b and 542b. This
make-before-break action is essentially the same as described with
reference to the contactors 238a and b of FIG. 25. The
make-before-break action also occurs when the push button 234 is
released to its extended position after being depressed a second
time, in the same manner as previously described.
The rivet 546b has a head with a low profile so that the rivet is
not engaged by the lower contactor 538a when it engages the fixed
contacts 540a and 542a. Thus, the contactor 538a does not engage
the rivet 546b at any time. It will be understood that the
connecting leads 532f are connected to terminals on the rivets
544a, 546a and 546b.
In the switch 230 of FIG. 25, the lower contactor 238a does not
engage the rivets 244b and 246b at any time. The lower contactor
238a is arrested in its downward movement by the contact points
240a and 242a and thus is prevented from engaging the rivets 244b
and 246b.
In the switch 530 of FIG. 29, the contactors 538a and b can move
apart to a spacing determined by the distance between the flanges
or retainers 307b and c on the sleeve or carrier 307a. This
distance determines the distance between the contactor surfaces
which are presented to the contact elements. In order to produce
the make-before-break action, such maximum distance between the
contactor surfaces of the contactors 538a and b should be greater
than the distance in an axial direction between the two sets of
contact elements, one set comprising the fixed contacts 540a and
542a, while the other set comprises the flanges 540b and 542b.
* * * * *