PCB-mounted contacts for 9V battery

[passerby]

Do you guys know where to order (or even what name to find them by) the little
contacts (clips?) that the 9V battery plugs into, but in a PCB-mounted
version. I've seen them on some boards, positive and negative terminals as
separate parts, positioned 90 degrees to the board (so the battery is parallel
to the board) and I'd be interested in those, too, but my immediate need is
something that I can solder flush with the board so that the battery stands on
its contacts on the PCB. I realize it's not very secure that way but it should
work for me.

I've seen TONS of pre-cabled contacts with both positive and negative
terminals but I'm looking for something that's solderable and does not include
parting out a connectorized contact.

Thanks!

--


--
+-----------------------[ SERVER SIGNATURE ]---
| posted via http://www.electrondepot.com
| Web, RSS and Social Media Interface to
| sci.electronics.components and other groups
+----------------------------------------------

 

[[email protected]]

Do you guys know where to order (or even what name to find them by)
the little contacts (clips?) that the 9V battery plugs into, but in a
PCB-mounted version.

Keystone has these in a couple of versions. The first one requires
something else (usually the enclosure) to keep the battery pushed into
the contacts:
http://www.keyelco.com/products/prod02a.asp?SubCategoryID=22

The second one looks just like the contacts on the top of the 9V
battery; it will stay reasonably "plugged into" the clips by itself:
http://www.keyelco.com/products/prod58.asp?SubCategoryID=21

Digi-Key and Mouser stock at least the "plug in" style.

Standard disclaimers apply; I don't get money or other consideration
from any companies mentioned.

Matt Roberds

 

[[email protected]]

Do you guys know where to order (or even what name to find them by)
the little contacts (clips?) that the 9V battery plugs into, but in a
PCB-mounted version.

Keystone has several variations. 968 and 967 seem to be closest to
what you want: http://www.keyelco.com/products/prod29.asp

The "90 degree" style comes in a couple of versions. The first one
requires something else (usually the enclosure) to keep the battery
pushed into the contacts:
http://www.keyelco.com/products/prod02a.asp?SubCategoryID=22

The second version looks just like the contacts on the top of the 9V
battery; it will stay reasonably "plugged into" the clips by itself:
http://www.keyelco.com/products/prod58.asp?SubCategoryID=21

Digi-Key and Mouser stock at least some of these contacts.

Standard disclaimers apply; I don't get money or other consideration
from any companies mentioned.

Matt Roberds

 

[passerby]

responding to
http://www.electrondepot.com/components/pcb-mounted-contacts-for-9v-battery-33322-.htm

mroberds wrote:

The second version looks just like the contacts on the top of the 9V
battery; it will stay reasonably "plugged into" the clips by
itself:
http://www.keyelco.com/products/prod58.asp?SubCategoryID=21

Thank you for your input! Looks like Keystone is the way to go. I also see the
exact version I needed - just the snap-on socket and the snap-on stud (and now
I know how they're called!) as separate components. I will still need to
figure out how to mount them on the board because they aren't solderable - the
mount type is shown as "custom" and I believe they are meant to be held in
place by some sort of a rivet.

So, that's going to become my next question then - how do you deign a board
for the .125" rivet? Do you make a .125" hole for it or larger? Will it damage
the FR board material when it gets squished if the hole is the exact size?
Does this need to be a plated hole? Do you solder it over after you installed
the rivet (from the back side, of course)?

Thanks in advance for all input you can provide on the rivet mounts!

--

 

[[email protected]]

I also see the exact version I needed - just the snap-on socket and
the snap-on stud (and now I know how they're called!) as separate
components.

Keystone part numbers 261 and 269?

I will still need to figure out how to mount them on the board because
they aren't solderable - the mount type is shown as "custom" and I
believe they are meant to be held in place by some sort of a rivet.

I think the rivet problem is why Keystone part numbers 967 and 968 exist.
They install the rivet for you, and the rivet has a PC pin coming out of
the bottom. You just need to provide two 0.086" holes on an 0.5" center
in the board. Note that the insulator will sit not quite flat on the PC
board, due to the rivets on the bottom side of the insulator. Keystone
does not specify the gap, but it looks to be on the order of 0.010" to
0.020" in http://www.keyelco.com/products/specs/spec105.asp .

So, that's going to become my next question then - how do you deign a
board for the .125" rivet?

Look closely at Keystone's catalog. The contacts that have an 0.125"
hole are marked as "Senior" size (262 and 270), which is the wrong size
for a 9 V battery. The "junior" size (261 and 269), for a 9 V battery,
have a smaller hole.

There is a single page from an older catalog at
http://www.keyelco.com/pdfs/M55p22.pdf which shows an 0.093" hole on
the stud and no data on the socket. Their complete current catalog,
available from http://www.keyelco.com/products/M60-pdf_download.asp ,
shows an 0.097" hole on the stud and an 0.096" hole on the socket on
paper page 30 / PDF page 37. So, you need a rivet that is smaller than
the hole.

The eyelets and rivets they have are on PDF page 141 / paper page 134 of
the complete catalog. Eyelet part numbers 22-27 and 33-37 have a narrow
enough shank to fit through the hole in the contacts. The length you
need depends on how thick your board is; remember that some of the
length will be used up when you round it off when installing. I can't
tell from the information given whether you want the 22-27 eyelets or
33-37 eyelets; the eyelet head has to fit inside the battery contact.

The 3381-3383 and 3384-3387 rivets may also work; their heads will stick
up more than the eyelets and may not fit as well in the contacts. Again,
I'm not sure which series you need.

Do you make a .125" hole for it or larger?

You pick the size based on the outside diameter of the eyelet or rivet
you are using. Keystone has recommendations for the eyelets and rivets
they sell; in general the hole is a little bit bigger than the outside
diameter of the eyelet or rivet. For instance, for an 0.089" diameter
eyelet, they call for an 0.093" diameter hole.

Will it damage the FR board material when it gets squished if the hole
is the exact size?

You have to be a little bit careful when you set (squish) the rivet. If
you set it too hard, then you may damage the board. I think you are
more likely to damage the board surface or trace than the inside of the
hole.

Does this need to be a plated hole?

Only if there will be traces connecting to the battery on the same side
as the battery snaps. If all the traces are on the other side of the
board from the battery snaps, they don't have to be plated holes.

Do you solder it over after you installed the rivet (from the back
side, of course)?

I would. Before plated-through holes existed, at least one TV
manufacturer tried to use rivets to join the traces on one side of the
circuit board to the other. They were soldered at the factory, but it
apparently didn't always work that well:
http://www.repairfaq.org/samnew/tvfaq/tvepwoge.htm This might be a good
job for a 100 W or so "gun" soldering iron, rather than a lower-rated
"pencil" iron; there's a lot of metal to heat up.

You will also need some kind of tool to set the rivets; Keystone sells
them.

Advice: If you are only making one or a few of this device, the 967 or
968 clips will be a lot easier to deal with; two PC board holes, two
pins to solder, done. (You or your PC board assembler will also find
this easier; you/they *know* how to solder things to a board.) If you
are making lots of this device, then it may make more sense to use the
rivet-on contacts. In this case, it might pay to get a sheet of
unetched circuit board material the same as what you will use in
production, order a few each of different sized rivets, and try
attaching the contacts. Then you know what you need before you order a
bunch, and you can talk to your board assembler about the correct rivet
technique. Also, if you are making lots of this device, it might be
worth an email to Keystone to see what they recommend.

Matt Roberds

 

[passerby]

responding to
http://www.electrondepot.com/components/pcb-mounted-contacts-for-9v-battery-33322-.htm

mroberds wrote:

I think the rivet problem is why Keystone part numbers 967 and 968
exist.
They install the rivet for you, and the rivet has a PC pin coming out
of
the bottom. You just need to provide two 0.086" holes on an
0.5" center
in the board. Note that the insulator will sit not quite flat on the
PC
board, due to the rivets on the bottom side of the insulator. Keystone

does not specify the gap, but it looks to be on the order of
0.010" to
0.020" in http://www.keyelco.com/products/specs/spec105.asp .

Thank you for the incredibly detailed answer, Matt. I think I understand the
situation much better now than when I started! It looks like the 967 clips are
the way to go for me - the rivets may be doable but require very careful
consideration but the pre-mounted ones only add less than 2mm to the height
and I think (need to see one up close first) I can route traces under the
contacts themselves because they are raised on the fiber insulator - will be
handy on what should be a very small board. I'll get myself a few to try and
go from there.
Thanks again!


--

 

[Cydrome Leader]

Using rivets for electrical contacts isn't too reliable if your board is
likely to see temperature cycling. The FR4 expands more than the rivet
at higher temperatures, so the FR4 gets squashed and cold-flows a bit to
relieve the stress. When the temperature comes down again, the preload
on the rivet has been reduced by the cold flow. There's nothing that
tends to make it flow back again, so repeated temperature cycles will
eventually reduce the preload to zero. It doesn't necessarily stop
there, either--the rivet can pull the copper away from the board and
crack it, making an open or intermittent contact.

So rivets are OK for mechanical mounting, but you need soldered joints
for higher reliability.

I've seen a few brass rivets used to join 9 volt battery terminals to
PCBs which all hardened and cracked over time. Thermal cycling should not
have been an issue for a device that just ran a few LEDs either.

Little bit of solder fix those things up.