U.S. patent number 3,924,918 [Application Number 05/404,290] was granted by the patent office on 1975-12-09 for daughter board contact.
This patent grant is currently assigned to E. I. Du Pont de Nemours and Company. Invention is credited to Lindsay Carlton Friend.
United States Patent |
3,924,918 |
Friend |
December 9, 1975 |
Daughter board contact
Abstract
An electrical connection between spaced and parallel mother and
daughter boards including terminals secured to the mother board and
projecting toward the daughter board having a pivot link arm with a
daughter board-engaging member at the free end of the link arm and
a daughter board spring contact. A number of terminals are secured
to the mother board all facing in the same direction so that upon
movement of the daughter board in a direction parallel to the
mother board the links pivot the daughter board down toward the
mother board and bring contact pads on the daughter board in
engagement with the spring contacts.
Inventors: |
Friend; Lindsay Carlton (Camp
Hill, PA) |
Assignee: |
E. I. Du Pont de Nemours and
Company (Wilmington, DE)
|
Family
ID: |
23599012 |
Appl.
No.: |
05/404,290 |
Filed: |
October 9, 1973 |
Current U.S.
Class: |
439/75; 439/329;
439/876; 361/776; 361/784 |
Current CPC
Class: |
H05K
3/368 (20130101); H01R 12/714 (20130101); H05K
3/3447 (20130101); H05K 2201/10871 (20130101); H05K
3/325 (20130101); H05K 2201/0311 (20130101) |
Current International
Class: |
H05K
3/36 (20060101); H05K 3/32 (20060101); H05K
3/34 (20060101); H01R 013/54 (); H05K 001/04 () |
Field of
Search: |
;339/17M,18,75M,91,174,176,99,97,275B,275R,220,95 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Frazier; Roy D.
Assistant Examiner: Lewis; Terrell P.
Attorney, Agent or Firm: Hooker; Thomas
Claims
What I claim as my invention is:
1. A daughter board contact system comprising a mother board, a
number of terminals secured to the mother board in spaced relation
and extending from one side thereof with each terminal including a
link-arm and a daughter-board engaging hook at the free end of the
arm, a number of spring contacts extending outwardly of said side
of the mother board, a daughter board having a number of
hook-receiving openings thereon and contact pads on one side
thereof for forming electrical connections with said spring
contacts, the hooks engaging said openings so that the arms space
the mother and daughter board relative to one another and said
spring contacts being biased against said pads to form electrical
connections between the mother and daughter boards, and means
holding the mother and daughter boards together against the spring
force of the spring contacts.
2. A daughter board contact system as in claim 1 wherein said means
comprises flexible latches mounted on the mother board and
engagable with the daughter board.
3. A daughter board contact system as in claim 2 wherein said link
arms normally extend away from the mother board at an acute
angle.
4. A daughter board contact system as in claim 2 including a spring
contact arm integral with each link arm.
Description
The invention relates to a connection system for two parallel
circuit boards, commonly referred to as mother and daughter boards.
The daughter board is removably mounted on the mother board in
electrical engagement with circuitry on the mother board. Landman,
U.S. Pat. No. 3,701,071 discloses a connector for forming an
electrical connection between spaced parallel mother and daughter
boards. The invention disclosed herein is directed to a different
type of connection system for parallel mother and daughter
boards.
According to the invention, terminals are secured on the mother
board and include link arms having hooks at the free ends of the
arms engagable with the daughter board overlying the mother board.
The terminals all include spring contacts so that when the daughter
board is laid on top of the terminals and engages the hooks,
lateral movement of the board pivots the board about the link arms
and brings contact pads on the surface of the daughter board
adjacent the mother board into engagement with the spring contacts
on the terminals. The hooks hold the daughter board down.
Additionally, other spring contacts may be secured to the mother
board for forming electrical connections with other contact pads at
desired locations on the daughter board. Latches or other types of
detents may be provided for holding the daughter board in
electrical engagement with the spring contacts of the terminals and
the additional spring contacts.
Ohter objects and features of the invention will become apparent as
the description proceeds, especially when taken in conjunction with
the accompanying drawings illustrating the invention, of which
there is one sheet.
IN THE DRAWINGS
FIG. 1 is a perspective view of a terminal used for forming
electrical connections between spaced parallel mother and daughter
boards;
FIG. 2 is a sectional view taken through the terminal of FIG. 1
illustrating the mother and daughter boards with the daughter board
in initial engagement with the terminal;
FIG. 3 is a view similar to that of FIG. 2 showing the mother and
daughter boards with a terminal in electrical connection with a pad
on the daughter board;
FIG. 4 is a view illustrating the mother and daughter boards with
the daughter board in position to be mounted on the terminals on
the mother board; and
FIG. 5 is a view, partially broken away, taken along line 5--5 of
FIG. 3 illustrating the closed mother and daughter boards.
The daughter contact 10 illustrated in FIG. 1 forms a physical and
electrical connection between spaced and parallel mother board 12
and daughter board 14. The terminal 10 includes a base 16, a solder
tab 18 extending from the base 16, a pair of supports 20 extending
to one side of the base 16, a pivot link arm 22 extending at an
angle from the edge of the base away from tab 18, and a pair of
cantilever spring contact arms 24 to either side of the pivot link
arm 22. A daughter board engaging hook 26 is provided at the free
end of the link arm and electrical contacts are provided at the
free ends of the cantilever spring arms 24. The terminal 10 is
preferably stamp formed from sheet metal stock of high yield
strength.
As illustrated in FIG. 4, a number of spaced terminals 10 are
mounted on the mother board 12 with the solder tabs 18 of the
terminals extending through circuit board holes 30 in the mother
board and secured to printed circuit 32 on the bottom of the mother
board by solder connections 34. The supports 20 of each terminal
rest flush on the top of the mother board to prevent movement of
the base during the formation of the electrical connections between
the mother and daughter board. The terminals 10 are mounted on
mother board 12 so that the pivot link arms 22 and cantilever
contact arms 24 all extend in the same direction. As illustrated in
FIG. 4, the arms all extend to the right hand side of the mother
board.
In addition to terminals 10, a number of individual contact
terminals 36 are also secured to the mother board 12. Each of these
terminals includes a solder tab 38 extending through a circuit
board hole and soldered to printed circuitry 40 on the bottom of
the circuit board of the mother board, and a single cantilever
spring arm 42 joining the tab and extending away from the top of
the mother board in the same direction as the link and spring arms
of terminals 10. As illustrated in FIG. 4, the contact arms 42 also
extend to the right of the mother board. Contacts 44 are provided
at the free ends of the spring arms 42. Spring arms 42 are the same
length as arms 24.
Daughter board latches 46 are secured to the edges of the mother
board 12 and include daughter board receiving recesses 48. The
terminal arms 22 and 24 and contact arms 42 normally project above
the lower edges of recesses 48.
As shown in FIG. 4, the terminals 10 are spaced from each other on
the mother board 12. Hook-receiving openings 50 are provided in the
daughter board with an opening above each terminal 10. Contact pads
52 to either side of openings 50 are provided for electrical
connection with the contacts 28 on arms 24. Additionally, a number
of contact pads 54 are provided on the daughter board in position
for forming electrical connections with the contacts 44 of contact
arms 36.
The daughter board is brought into electrical connection with the
mother board by first positioning the daughter board parallel to
and above the mother board with the hooks 26 of terminals 10
extending through the openings 50 so that they engage the top of
the daughter board. In this position, the daughter board rests
lightly upon contacts 28 and 44. The daughter board is then pushed
to the right so that it pivots about the link arms 22 of the spaced
terminals 10 and is brought down toward the mother board so that
the spring arms 24 of terminals 10 and the arms 42 of contacts 36
are bent down and stressed and their respective contacts 28 and 44
are biased against the contact pads 52 and 54 on the daughter
board. Terminals 10 are bent at each end of link arms 22. Thus, the
daughter board is pivoted to one side and moved down about the arms
22 toward the mother board and engages flexible latches 46. The
latches are bent outwardly from the mother board and then snap back
to secure the daughter board in the position of FIG. 5 with
daughter board contact pads 52 and 54 in electrical connection with
the arms 24 and 36 of the mother board. The daughter board may be
released from the mother board by opening the latches 46.
While terminals 10 disclosed herein include a single link arm 22
and a pair of contact arms 24, it is obvious that connections may
be formed between the mother and daughter boards as disclosed
through the use of a contact and connection system having a number
of link arms and a number of contact arms, whether or not the
contact arms are integral with the link arms.
While I have illustrated and described a preferred embodiment of my
invention, it is understood that this is capable of modification,
and I therefore do not wish to be limited to the precise details
set forth, but desire to avail myself of such changes and
alterations as fall within the purview of the following claims.
* * * * *