U.S. patent number 3,917,921 [Application Number 05/505,179] was granted by the patent office on 1975-11-04 for slide actuated switch.
This patent grant is currently assigned to Illinois Tool Works Inc.. Invention is credited to Alexander J. Jakubauskas.
United States Patent |
3,917,921 |
Jakubauskas |
November 4, 1975 |
Slide actuated switch
Abstract
A switch in which the U-shaped slide actuator that is employed
for each switching stage of the switch fits over the contacts of
the switching stage so as to slide back and forth in order to
operate the switching stage is disclosed. At each switching stage
one of the leads is L-shaped with a contact area, while the other
is L-shaped with an S-shaped contact section. In assembly of the
switch, a plurality of such leads are formed on a single stamped
sheet and the base of the switch is split into two halves, one half
of which is molded over one set of leads; and the other half of
which is molded over the other set of leads. The leads are then cut
away from the remainder of the stamped sheets and the two halves of
the base are secured together. A cover may be snapped onto the top
of the switch so that automatic insertion equipment can pick up the
switch by suction for automatic insertion of the leads of the
switch into a printed circuit board.
Inventors: |
Jakubauskas; Alexander J.
(Chicago, IL) |
Assignee: |
Illinois Tool Works Inc.
(Chicago, IL)
|
Family
ID: |
24009340 |
Appl.
No.: |
05/505,179 |
Filed: |
September 11, 1974 |
Current U.S.
Class: |
200/333; 29/756;
200/293; 29/622; 200/16R |
Current CPC
Class: |
H01H
11/0056 (20130101); H01H 15/005 (20130101); Y10T
29/49105 (20150115); Y10T 29/53248 (20150115) |
Current International
Class: |
H01H
11/00 (20060101); H01H 15/00 (20060101); H01H
009/02 () |
Field of
Search: |
;200/333,304,293
;29/622,23B |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Schaefer; Robert K.
Assistant Examiner: Smith; William J.
Attorney, Agent or Firm: Beart; Robert W. Bowen; Glenn
W.
Claims
The invention is claimed as follows:
1. An electrical switch and cover assembly comprising a housing, a
first lead having a first contact area, a second lead having a
second contact area which overlaps said first contact area, an
electrically insulated slide actuator slidable back and forth in
said housing and having a projection thereon which in a first
position of the slide actuator is not in contact with either said
leads and in a second position of said slide actuator is in contact
with said second lead so as to force said second contact area into
contact with said first contact area, an aperture in a surface of
said housing, an actuating member on said slide actuator which
projects through said aperture to allow for external actuation of
said switch, a cover for covering said aperture in said surface of
said housing so as to substantially seal off leakage air paths
associated with said aperture when a suction pick-up means is
placed adjacent said apertured surface having snap-on holding means
for temporarily securing said cover on said switch which fits over
the top of said switch and comprises a pair of resilient legs that
contact the sides of the switch and which have feet that grip the
bottom of the switch.
2. An electrical switch and cover assembly comprising switching
means, a housing for said switching means, a plurality of contact
leads positioned to be insertable into the apertures of a printed
circuit board, an aperture in the surface of said housing, an
actuator for actuating said switching means that projects through
said aperture, a cover for covering said aperture in said surface
of said housing so as to substantially seal off leakage air paths
associated with said aperture when a suction pick-up means is
placed adjacent said aperture surface having snap-on holding means
for temporarily securing said cover on said switch which fits over
the top of said switch and comprises a pair of resilient legs that
contact the sides of the switch and which have feet that grip the
bottom of the switch.
Description
BACKGROUND OF THE INVENTION
In order to provide microminiature electrical switches with a high
reliability at a relatively low cost, a minimum number of parts
must be utilized. In a switch constructed in accordance with the
present invention, the size of the switch may be maintained very
small, although the switch of the present invention may be utilized
for much larger applications, if desired. Small size is
maintainable in the switch by using a slide actuator, which except
for a small extending actuating knob, is housed completely within
the housing of the switch. Another factor that assists in
maintaining reliability and keeping the size of the switch to a
minimum is that the switch utilizes a simple protuberance on the
slide actuator for operating the switch. In addition, no spring
members are employed in the switch other than the leads.
Although the design of the switch of the present invention may be
utilized for a single switching stage, it is especially
advantageous for use as a multiple-stage switch, especially in view
of its construction which makes it adaptable to a novel method of
assembly. In accordance with this assembly method, each pair of
L-shaped leads are initially joined to a plate member on a stamped
sheet of metal. The base is split into two halves which are each
molded over one set of leads. The leads are then cut and the two
base halves are placed together and ultrasonically welded or
secured by other means to form the completed base structure. A top
housing member having apertures in it for guiding the slide
actuating member back and forth which fits over the base member to
complete the structure of the switch.
The switch disclosed herein is especially adapted for use on a
printed circuit board program board for data processing equipment.
This type of switch must be small in size and easily actuatable.
The switch of the present invention fulfills these requirements.
Although, automatic insertion equipment used to insert microcircuit
components of similar size and shape into printed circuit boards is
ineffective with switches of this type due to a large extent
because of the air leakage path provided in the top of these
switches around the sliding actuators. The switch of the present
invention may be picked up and utilized with this equipment because
of the addition of a snap-on cover which fits over the top of the
switch.
Description of the Drawings
FIG. 1 is a perspective view of a multi-stage embodiment of the
present invention;
FIG. 2 is a cross-sectional side view of one switch section
constructed in accordance with the present invention with the
contacts open;
FIG. 3 is a cross-sectional side view of one switch section
constructed in accordance with the present invention with the
contacts closed;
FIG. 4 is a partial cross-sectional end view showing the position
of the slide actuators with respect to the contacts for the switch
of FIG. 1;
FIG. 5 is a top view of a multiple-lead stamped sheet and base
assembly, with the two halves of the base being molded on the leads
prior to construction of the switch;
FIG. 6 is a side view of the multiple-lead and base assembly of
FIG. 5;
FIG. 7 is a top view of the switch with the snap-on cover
utilized;
FIG. 8 is a side view of the switch with the snap-on cover
utilized; and
FIG. 9 is an end view of the switch with the snap-on cover
utilized.
Technical Description of the Invention
Referring to FIG. 1, there is shown an electrical switch 10
constructed in accordance with the present invention that has a
number of switching sections which are encased in the same housing
12. Each switching section of the switch 10 has a resilient first
lead 14 and a resilient second lead 16, the terminal ends of which
extend from the base 18 and the upper ends of which form the
contact areas for the particular switching stage. Also associated
with each switching stage is a slide actuator 20 which has an
actuating knob 22 that extends upwardly through an elongated
aperture 24 in the top surface of a top housing member 28 for the
switch. Large size versions of the switch 10 of FIG. 1 may be
actuated by hand; but if the switch is very small, it may be
actuated by a driven operating member 30 that is shaped to fit in a
small indentation 32 made in the top of the actuating knob 22.
The leads 14,16 are generally L-shaped and the lead 14 has a
contact area 33 on its upper leg 34 while the lead 16 has a contact
area 40 on its upper leg 36. The contact area 40 is actually a
downward bend which, along with the upward bend 38, forms an
S-shaped contact section. The contact area 40 contacts the contact
area 33 of the lead 14 when the switch is closed. The slide
actuator 20 has a general U-shaped configuration with sidewalls 20a
and 20b that project over the legs 34,36 of the leads 14,16. The
actuator 20 is thereby guided in its back and forth motion by the
aperture 24 and by the legs 34,36. The actuation of the switch 10
is achieved by interaction of a downwardly projecting actuating
member 42 formed on the slide 20 which contacts the upward bend 38
to force the downward bend 40 into contact with the contact area 33
when the switch is closed.
When the slide actuator 20 is positioned to the right, as shown in
FIG. 2, the downwardly projecting actuating member 42 is not in
contact with the bend 38; and, therefore, the normally open contact
leads 14,16 are not closed. However, when the slide actuator 20
moves to the left, as shown in FIG. 3, the actuating member 42
comes into contact with the bend 38 forcing the contact leads 14,
16 together to close the switch. In order to cam the actuating
member 42 downwardly when the slide actuator is moved toward the
left, the upper surface 26 of the housing member 28 is provided
with a sloping wall 28 on its under portion, which engages a slight
wedge 46 on the slide actuator 20.
A multiple-stage version of the described switch may be constructed
by initially forming a plurality of lead sections 50 on a single
stamped sheet metal member 48; with the base 18 being formed in two
separate halves 18a, 18b, as shown in FIG. 5. The plurality of
leads 14,16 are then bent downwardly, as shown in FIG. 6 and the
base halves 18a, 18b are molded onto the leads 14, 16,
respectively. The leads 14,16 are initially interconnected by the
central plate 52 of the stamped member 48 and by the bars 54,56. As
shown in FIG. 6, the plate 52 and the leads 14,16 then have a
general overall C-shaped configuration. Following molding of the
base members 18a, 18b onto the leads 14, 16, the bars 54,56 are
removed and the plate 52 is severed along the lines 53,55 in order
to separate the individual switching stages or sections of the
switch. When the leads 14,16 are molded into the base halves 18a,
18b, it is desirable that they be formed with enlarged sections
58,60 in order to firmly secure the leads into the base halves.
After the plate 52 and the bars 54,56 have been severed, the base
halves 18a, 18b are supported on a support member (not shown) by
the flat surfaces 62,64, with the lefthand edge 66 of the base half
18a being in contact with the righthand edge 70 of the base half
18b so that the projection 68 on the base half 18b projects into a
corresponding aperture 69 on the base half 18b. The base halves
18a, 18b are then ultrasonically welded or secured together by
other suitable means. The housing member 28 is then placed over the
assembly and snapped into place so as to form a complete housing
assembly.
The switch 10 of the present invention is preferably of a shape and
size that is substantially the same as multi-lead microcircuit
component packs. Many of these circuit packs are inserted by
automatic insertion equipment into printed circuit boards by means
of a vacuum pick-up. More efficient use of a programmable switch of
a similar size and shape could, thus, be achieved if these switches
could be picked up by the suction pick-ups that are used to
transport the microcircuit packs so as to achieve automatic
insertion of the leads of these switches in the appropriate
apertures of the printed circuit boards. However, mechanically
actuable programmable switches generally have apertures around
their actuators that create leakage air paths that interfere with
reliable suction pick up by automatic machines.
In order to overcome this difficulty, a cover 80 constructed of
plastics or other suitable material is designed to snap on the
switch 10 of the present invention. The cover 80 has resilient legs
82,84 which contact the sides 83,85 of the switch and have feet
86,88 that grip the bottom 90 of the housing of the switch. The
cover 80 may abut the top surface 26 of the housing member 28, or
it may have a shoulder 92 formed thereon to hold it slightly off
the surface 26. Since vacuum pick will be achieved by suction
applied to the top, preferably flat, surface 94 of the cover 80
which covers the underlying apertures 24, the slight opening
provided at the ends of the switch by the shoulder 92 will prevent
pick-up of the switch by a pick-up probe. Slot 96 may be provided
approximately midway along the length of the legs 82,84 to increase
the flexibility of the legs for easier snapping of the cover 80 on
the switch 10, and also to provide for easier removal of the cover
from the switch.
* * * * *