Hi smart people!
I'm very new to all of this circuit board stuff (sorry in advance for all the wrong terminology), however I love a challenge, so I've taken it upon myself to repair some lab equipment.
For those interested, this is what I'm repairing:

I've already repaired 2 of these, using a third one for spare parts. However I would also like to try and repair the third one.

So... What I'm looking for are some spare parts, more specifically these things:

They are a type of switch, where when you push from the side, the metal thing presses down a button (here in red), which flicks a cobber-part to activate a circuit and start a rotor (that will suck up liquid). All of the faulty ones I have are broken in the plastic, which has ruined the circuit, and super-gluing them hasn't really been successful.

Anybody know what they are called, and where to buy them? I've found some on pages like Aliexpress, but only AC, which I'm not sure will work.
The ones I'm replacing has the stamp "0.1A5VDC", so I'm guessing I need them to be 100mA, 5V and DC compatible. Or can I stray from this in any way?

Thanks a bunch!
/Newbie (Patricia)

 

I believe it is called a lever switch.

But my question is: what is that thing you are repairing?

Bob

 

Hello,

Those microswitches come in a lot of different sizes.
Also the lever can have different sizes and shapes.

Have you taken the size of the old switch?

Have a look at the attached Cherry catalog to compare the size you got.

Bertus

 

Should be available at Digikey. Made-by and called Microswitches as per post #3.
Max..

 

Hello,

The price of the switches will be next to nothing compared to a new pipet controller:
https://www.fishersci.com/shop/products/brandtech-accu-jet-pro-pipet-controller-7/p-3148144
I hope you can find the correct switch.

Bertus

 

Are you sure the pipette has only on and off using a switch? The ones I’ve used are more like variable speed power tools - they allow a range of delivery speed.

 

Anybody know what they are called, and where to buy them? Thanks a bunch!

Typically they should have make and model No. on the side.
Max.

 

Thanks, you guys! This is super helpful! Looks like digi-key has them!

@BobTPH: It's what we call a "pipet-boy". So it's basically like a big pipette for sucking and spitting out liquid of around 1-50 ml (you need to stick a pipette tip with measuring lines in the front piece in order for it to work). We use them all of the time in f.i. the cell lab. Very simple, VERY useful tool

@bertus: I know! But also, all lab equipment is insanely jacked up in prices. The wall chargers alone for these things (just standard wall chargers, nothing special) are $80 dollars. Insane... And don't even get me started on the velcro for attaching these guys to the wall!
Ahh, would make sense that they come in several sizes. I just did a search through Aliexpress, and the measurements on there were all exact to my piece, so I though it was a "standard size". These are the measurements:

So should be able to find on your suggested sites

@wayneh: True - they do have a dial on the back, which controls the speed. However, it seems to be only controlling the speed of the motor, while pressing the buttons only presses in on these switches to turn the motor on or off (running in one or the other direction to suck or spit). It does feel like applying less pressure to the buttons makes the liquid run slower. I don't know if it's because the cobber plate inside is making a "slight" circuit, or maybe it's just in my mind.

I've uploaded an actual picture of the inside of the pipette so that it hopefully makes more sense (color codes in text matches picture). There's also this annoying switch on the top that opens/cuts the circuit to the out-spitting button (I don't know why you would ever need that). In my original plan, lacking spare parts, I tried to "solder it off" in order to use that piece as a replacement since it's absolutely useless. However, I'm not exactly sure how it would affect the circuit (I wanted it to be permanently stuck on "on") + I didn't seem to be able to get it off .

 

When I was in high school, I entered a program that placed a few students in various labs for the summer. I was at the AFIP ( Armed Forces Institute of Pathology) at Walter Reed medical center, in the Virology lab.

The group I was worrking with, worked with live Hepatitis virus. Some of the work we did involved transferring solutions containing the virus into tissue cultures, which was done with pipettes. We did not have snazzy gadgets like the one in this thread. The people I worked with just sucked the solution into the pipette with their mouth. I was a wimp, apparently, because I used a rubber bulb.

Bob

 

When I was in high school, I entered a program that placed a few students in various labs for the summer. I was at the AFIP ( Armed Forces Institute of Pathology) at Walter Reed medical center, in the Virology lab.

The group I was worrking with, worked with live Hepatitis virus. Some of the work we did involved transferring solutions containing the virus into tissue cultures, which was done with pipettes. We did not have snazzy gadgets like the one in this thread. The people I worked with just sucked the solution into the pipette with their mouth. I was a wimp, apparently, because I used a rubber bulb.

Bob

Haha! Oh no! I hope the people there had their vaccines in check . That's hilarious! Mouth-pipetting is definitely a thing of the past. Thank god for pipet-boys . We also probably wouldn't let a highschooler play around with Biosafety level 2 agents.

 

@wayneh: True - they do have a dial on the back, which controls the speed. However, it seems to be only controlling the speed of the motor, while pressing the buttons only presses in on these switches to turn the motor on or off (running in one or the other direction to suck or spit). It does feel like applying less pressure to the buttons makes the liquid run slower. I don't know if it's because the cobber plate inside is making a "slight" circuit, or maybe it's just in my mind.

The image you provided shows the spring behind de buttons. Once you press one of them, you start the motor with the microswitch and if you keep pressing deeper, it seems that inside the white plastic body, the actuator associated to the button is serving as a valve which controls the flow.

The manual actually mentions something like that, in a much better English than mine.

 

Typically called a Micro Switch after the first company to market them. Snap Acting switch is another popular name which gets down to the type action, button, roller, lever (which you have). A Google will turn up dozens fresh from China. Amazon Micro Switch With Lever will get you started finding the size you want. Find your body size, pin out and lever length.

Ron

 

Hello,

This query should find you a seller:
https://search.yahoo.com/search?n=1...f=all&vm=i&fl=0&fr=altavista&p="dg13b1la"&vs=

Bertus

 

As others have said, its a simple lever micro switch, the first place I go for components is Aliexpress, or failing that ebay.