Tact Switch

Details Tact Switch Tact Switch

1999-10-29

2001-01-30

Friedhofer, Michael (Department: 2832)

Electricity: circuit makers and breakers

Snap

Double snap

C200S517000, C200S573000, C200S551000

Reexamination Certificate

active

06180903

ABSTRACT:

BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a tact switch in which a plurality of separate contacts may be electrically connected together with relative short transmission path via operation on the tact switch.
2. The Related Art
Tact switches which have quick response to a manual depression have been used in many appliances such as in telephone sets, microwaves, remote controls, digital camera, TV sets, and etc. The inventor of the present invention has applied an U.S. patent application Ser. No. 09/384477 which is enclosed herein and shown in
FIGS. 3
,
4
,
5
and
12
. The tact switch as disclosed in U.S. application Ser. No. 09/384477 comprises a metal cover
1
, a pusher
2
, a support
3
, a water-proof tape
4
, a metal dome
5
, a conductor plate
6
, and a base
7
. Referring to
FIGS. 12 and 3
, the metal cover
1
has a rectangular plate
10
from front and rear edges of which four tangs
11
extend downward, and from side edges of which two tabs
12
extend downward, wherein the tangs
11
extending from the front edge of the rectangular plate
10
are spaced from each other with a predetermined distance. Each tang
11
has a laterally extended portion
111
extending from one end thereof. A lever
13
extends from the rear edge of the plate
10
having a curved shape under the plate
10
and including an upper contacting portion
131
proximate to the plate
10
and a lower depressing portion
132
defined adjacent to a curved end
133
thereof.
Also referring to
FIG. 4
, the pusher
2
has a T-shaped body
21
, a touch pad
22
integrated with a neck portion of the T-shaped body
21
, a pair of outer fingers
23
and a pair of inner fingers
24
extending horizontally from a wide rear edge of the T-shaped body
21
. A ramp
25
is formed in a middle portion of the rear edge substantially between the inner fingers
24
. The outer finger
23
is longer than the inner finger
24
. Rails
241
and
211
are respectively formed on top surfaces of the inner fingers
24
and the T-shaped body
21
.
The support
3
is a metal plate having a cutout
30
defined from a rear edge thereof. A pair of first tabs
31
extend upward from opposite edges of the cutout
30
and each of the first tabs
31
is positioned between one pair of the outer finger
23
and the inner finger
24
for guiding the movement of the pusher
2
. A pair of second tabs
32
extend upward from a front edge of the support
3
. The metal dome
5
has an upper central area
51
having a rectangular shape and substantially at the top of the metal dome
5
. The water-proof tape
4
is made of insulative material and adhered to the upper central area
51
of the metal dome
5
. The conductor plate
6
has four spring arms
61
defined in a middle area thereof, and each spring arm
61
has a downwardly bent end
611
.
Also referring to
FIG. 5
, the base
7
has four contacts
74
partially embedded in a dielectric housing
72
by insert molding. The housing
72
has a periphery wall
71
enclosing therearound thereby defining a cavity (not labeled) therein. Steps
73
are formed on opposite sides of the bottom surface (not labeled) of the cavity and four contacting portions
741
of the contacts
74
expose to external from the bottom surface of the cavity. The periphery wall
71
has an upper surface
751
which is higher than the steps
73
. Two U-shaped upper walls
75
extend upward from the periphery wall
71
and define a front entrance
76
and a rear entrance (not labeled) therebetween.
Four shallow portions
710
are defined in front and rear sides of the periphery wall
71
for engagement with the bent ends
111
of the tangs
11
of the metal cover
1
. Two grooves
750
are formed in opposite sides of the U-shaped upper walls
75
for engagement with the tabs
12
of the metal cover
1
.
In assembling, the conductor plate
6
is positioned on the two steps
73
, the metal dome
5
to which the central portion of the water-proof tape
4
adheres is positioned on the conductor plate
6
. Edge portion of the water-proof tape
4
is attached on the upper surface
751
of the periphery wall
71
preventing water from entering the cavity surrounded by the periphery wall
71
. The support
3
is positioned on the upper surface
751
of the periphery wall
71
, with the second tabs
32
, the side edges, and the rear edge thereof being retained between inner surfaces of the U-shaped upper walls
75
. The pusher
2
is positioned on the support
3
, with the first tabs
31
of the support
3
being retained in each pair of the outer finger
23
and the inner finger
24
of the pusher
2
and the outer fingers
23
thereof being spaced from the U-shaped upper walls
75
of the base
7
with a predetermined distance. Finally, the metal cover
1
is assembled onto the base
7
by engaging the bent ends
111
of the tangs
11
within the shallow portions
710
of the periphery wall
71
, and engaging the tabs
12
thereof with the grooves
750
of the periphery wall
71
, meanwhile the upper contacting portion
131
of the lever
13
abuts against the ramp
25
of the pusher
2
, and the lower pressing portion
132
of the lever
13
movably surrounded by the inner periphery of the cutout
30
of the support
3
.
During operation, the pusher
2
is pressed horizontally by a user until the outer fingers
23
thereof abuts against the U-shaped upper walls
75
of the base
7
. Upon depression on the pusher
2
, the ramp
25
moves forward to drive the lever
13
of the metal cover
1
, thereby forcing the lower pressing portion
132
of the lever
13
to depress the metal dome
5
, which in turn depresses the conductor plate
6
and causes the spring arms
61
and their bent ends
611
to electrically connect to the contacting portions
741
of the contacts
74
, thereby simultaneously and electrically connecting the four contacts
74
. When the metal dome
5
is depressed to force the conductor plate
6
to connect the contacting portions
741
of the contacts
74
, the user will have a “click” feeling due to the deformation of the metal dome
5
. A reverse operation occurs when the depression on the pusher
2
is released, and the four contacts
74
recover to electrical disconnection status.
Although the previous tact switch disclosed in the copending parent application, works well, a conductive path defined in each spring arm
61
and the outer periphery of the conductor plate
6
for electrically connecting the four contacts
74
is relatively long which will affect the response time of the tact switch. Moreover, if the metal dome
5
does not depress the four spring arms
61
simultaneously, the electrical connection of the four contacts
74
may not be achieved. It is requisite to provide a new structure to solve the above problems.
SUMMARY OF THE INVENTION
The primary purpose of the present invention is to provide an improved tact switch which can provide a reliable connection effect to a plurality of normally separated contacts therein.
Another purpose of the present invention is to provide an improved tact switch which can provide a relatively short conductive path for electrically connecting a plurality of normally separated contacts therein.
According to one aspect of the present invention, a tact switch comprises an insulative base having contacts partially retained therein and partially exposing to exterior, wherein the exposed portions of the contacts face upward. Two separated steps are formed in the insulative base and located beyond the exposed portions of the contacts. A conductor plate has a frame positioned on the separated steps, an integral contacting portion surrounded by the frame and connected to the frame via two spring arms. Normally, the contacting portion registers with and separates from the exposed portion of the contacts. An elastic device is positioned on the conductor plate and it is deformable by depression thereon to thus deform the spring arms of the conductor plate and move the integral contacting portion of the conductor plat

Affiliated with

Also associated with

Rating

Tact Switch does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Tact Switch, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Tact Switch will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2515761