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Beier variable-ratio gear

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with a thickened rim. The planet disks are tapered across their radius, at an included angle of around 3°. When the disks are intermeshed, they thus only contact at the rim of the central pack, no matter what the spacing of the shafts. These planetary disk packs have a gear meshing with a gear on the swing arms' fulcrum shafts, which in turn meshes with a central gear, used for the input drive. The central shaft is the output shaft and the gear is used as a reduction gear. When the disks are moved outwards, the central rim drives on the outside radius of the similar-sized tapered disks and the overall ratio is around 1:1. As the swing arms are moved inwards, the tapered disks are forced between the central rims against their spring-loading. The effective radius of the tapered disks is thus reduced and the gear ratio increases. The gear is made in a variety of ratio ranges, typically from 3:1 to 10:1. Overall efficiency is good, greater than 90%.
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In contemporary use, the Beier variator is most widely used as part of an industrial motor drive. An electric induction motor is driven at its ideal speed, derived from the electrical line frequency, and the variator drive is used to manually adjust its output speed. These are often coupled with a
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The mechanism consists of a spring-loaded stack of thin disks on a central shaft. Around this are arranged other stacked disk packs on a number of planetary shafts, usually three. These shafts are mounted on swinging arms, so that they may be moved in and out together. The central disks are thin,
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drag through a thin oil film between them. This has little slip, less than 1%, and the lack of friction reduces the losses through heat and thus permits a small compact mechanism to still handle a high power. Oil is often pumped through the drive, also having a cooling effect.
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The gear relies on the inter-meshing of a number of thin disks. By varying their separation, the effective radius of one disk varies, thus changing the overall gear ratio. This varying-radius principle is shared by a number of other
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mechanisms. An advantage of the Beier is that a large number of disks may be stacked on a common shaft, thus increasing its
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The drive was developed by Dr Beier, an Austrian working in Germany. Some of its first applications were as an
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that coupled a diesel piston engine together with a gas turbine and axial-compressor
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is a mechanical drive offering a continuously variable
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capacity for only a small increase in overall length.
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Unlike most other variators, but in common with the
159:"Napier Nomad: An engine of outstanding efficiency" 112:was achieved by varying the ratio of this drive. 201: 202: 120:to provide an extra-low speed output. 190:"Gearboxes catalogue: Beier Variator" 13: 215:Mechanical devices using viscosity 96:In 1951, it was used in the E.145 72:, the Beier gear does not rely on 14: 226: 76:between the disks, but rather on 100:aero engine. This was a complex 51: 84: 182: 1: 135: 7: 123: 28:between input and output. 10: 231: 50: 45: 18:Beier variable-ratio gear 57:Diagrams of Beier drive 91:automatic transmission 102:turbo-compound engine 157:(30 April 1954). 62: 61: 222: 194: 193: 186: 180: 179: 177: 175: 163: 151: 130:Hele-Shaw clutch 108:. Supercharging 70:Hele-Shaw clutch 55: 54: 43: 42: 230: 229: 225: 224: 223: 221: 220: 219: 200: 199: 198: 197: 188: 187: 183: 173: 171: 161: 152: 143: 138: 126: 118:cycloidal drive 87: 52: 12: 11: 5: 228: 218: 217: 212: 196: 195: 181: 140: 139: 137: 134: 133: 132: 125: 122: 86: 83: 60: 59: 48: 47: 46:External image 22:Beier variator 9: 6: 4: 3: 2: 227: 216: 213: 211: 208: 207: 205: 191: 185: 169: 168: 160: 156: 155:Gunston, Bill 150: 148: 146: 141: 131: 128: 127: 121: 119: 113: 111: 110:boost control 107: 103: 99: 94: 92: 82: 79: 75: 71: 66: 58: 49: 44: 41: 39: 35: 29: 27: 23: 19: 184: 172:. Retrieved 165: 114: 106:supercharger 98:Napier Nomad 95: 88: 85:Applications 67: 63: 30: 21: 17: 15: 174:18 December 204:Categories 136:References 93:in buses. 26:gear ratio 210:Variators 170:: 543–551 124:See also 74:friction 34:variator 78:viscous 167:Flight 38:torque 162:(PDF) 176:2009 16:The 20:or 206:: 164:. 144:^ 192:. 178:.

Index

gear ratio
variator
torque
Diagrams of Beier drive
Hele-Shaw clutch
friction
viscous
automatic transmission
Napier Nomad
turbo-compound engine
supercharger
boost control
cycloidal drive
Hele-Shaw clutch



Gunston, Bill
"Napier Nomad: An engine of outstanding efficiency"
Flight
"Gearboxes catalogue: Beier Variator"
Categories
Variators
Mechanical devices using viscosity

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