Manual adjuster for prestressing a differential gear and method of making a differential gear using same

A method of making a differential gear which has

• a gear box with first and second axially spaced gear box grooves,
• a gear axle carrying a ring gear which in use meshes with a bevel drive pinion, said gear axle having first and second axle ends,
• a first retaining ring insertable in the first gear box groove,
• a first tapered roller bearing having a first roller bearing ring resting against the first retaining ring and operable to support the first axle end at the gear box,
• a second retaining ring insertable in the second gear box groove, and
• a second tapered roller bearing having a second roller bearing ring resting against the second retaining ring and operable to support the second axle end at the gear box,
• wherein tooth play between the ring gear and bevel drive pinion and prestressing force at the roller bearings are dependent on axial thicknesses of the first and second retaining rings,
• said method including
• (i) providing an adjusting assembly including:
• a first adjusting device having a first tension bush supportingly engageable in the first gear box groove, a first pressure piece axially displaceable in the first tension bush and supportable at the first roller bearing ring, and a first adjusting spindle operable to displace the first pressure piece with respect to the first tension bush, and
• a second adjusting device having a second tension bush supportingly engageable in the second gear box groove, a second pressure piece axially displaceable in the second tension bush, and a second adjusting spindle operable to displace the second pressure piece with respect to the second tension bush,
• said first and second adjusting devices including measuring devices indicating desired retainer ring thicknesses based upon use of the adjusting devices to determine desired tooth play between the ring gear and bevel drive and pinion prestressing force at the tapered roller bearings, and
• using said adjuster assembly to determine desired thicknesses of the retainer rings and subsequently to remove the adjusting devices and insert the retainer rings for final assembly of the differential gear.