9

Sometimes there are these two half-arrow symbols on PCBs and on enclosures. See the images, for examples.

Those symbols are often placed near the screws, that are to be unscrewed upon disassembly.

Are these symbols standardised? If yes, which standard they are from?

Transistor
  • 168,990
  • 12
  • 186
  • 385
PF4Public
  • 654
  • 5
  • 13
  • 1
    Can't say i have seen them on all the items I have had apart - but they may well be standard somewhere. – Solar Mike May 26 '19 at 19:08
  • I often see a triangle pointing to disassemby screws. – Jasen Слава Україні May 26 '19 at 19:13
  • 1
    Sony discman, 1994 used this symbol on case screws. – tomnexus May 26 '19 at 19:23
  • 1
    On top of that @tomnexus said, all Japanese products I’ve taken apart have had these arrows to show which order at which a product is taken apart. – winny May 26 '19 at 20:19
  • 1
    @SolarMike That's exactly what I thought, stumbling on this symbol once again :) – PF4Public May 27 '19 at 15:11
  • @Jasen I've also seen triangles quite a lot, but a triangle is such a _simple_ shape, that virtually _anyone_ could come up with it. _These_ symbols, however... they are a little bit more complicated, so that someone, putting _them_ instead of, say, triangles squares or whatever, must have done it on purpose, which suggests some sort of standard. Unfortunately, I could not find it myself :( – PF4Public May 27 '19 at 15:16
  • Does it matter if it is a "standard"? A smart electro-mechanical designer will find the right symbol to assist the user. It comes with no additional cost.. – Tony Stewart EE75 Jul 24 '19 at 02:47
  • @SunnyskyguyEE75 No, it doesn't. And in fact the question just assumes that it **could** be and is asking **whether** it is standardised. – PF4Public Jul 25 '19 at 16:24
  • it's not in my IPC standards. A good question is why should it be? Perhaps if there was reason to have imbiguity or to have a standard in the 1st place is what counts. – Tony Stewart EE75 Jul 26 '19 at 00:23

1 Answers1

2

After extensive* searching on the web with multiple search engines, I was (very surprisingly) unable to find any information about this symbol - which is honestly absurd, considering just how often I've encountered this symbol myself while disassembling PCs and other electronic equipment.

I was also unable to find it on any disassembly guide or PCB symbol chart.

This leads me to believe that this is some sort of informal standard used by PCB/equipment designers. It may very possibly be a regional thing too, since all my searches were in English.

Here's an incomplete list of stuff I've seen the symbol on, in case it helps someone with more experience identify it:

  • A 2001 Yamaha Synth
  • A 2012 HP All-in-one
  • A 2007 Sony home theater
  • A 1998 HP Brio tower
  • Various HDD enclosures

*Most of my searches were combinations of the following terms (tried both with and without double quotes), on Google and DuckDuckGo: pcb, mounting, hole, screw, symbol, arrow, pointer, disassembly, pdf, schematic.

undo
  • 187
  • 5