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Toroidal internal combustion engines
A toroidal internal combustion engine made by Rotoblock.
Via: Rotoblock, after finding a similar engine in the excellent “The How and Why of Mechanical Movements” by Harry Walton.
Screw drive types
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Slotted (flat or straight) |
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Phillips (“crosshead”) PH |
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Pozidriv (SupaDriv) PZ |
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Square |
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Robertson (square) |
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Hex |
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Hex socket (Allen) |
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Torx T & TX |
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Security Torx TS |
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Tri-Wing |
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Torq-set |
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Spanner head (Snake-eye) |
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Triple square XZN |
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Polydrive |
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One-way |
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Spline drive |
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Double hex |
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Bristol |
From Wikipedia’s series on screw drive types, which is, thankfully, an actual topic. These are like mechanical emoticons.