Jack Ubersax
Aluminum
- Joined
- Mar 5, 2005
- Location
- Wilbraham, MA
Warner and Swasey's engineering strength and progressive machine design was found in many ways during its long history. One of these important design aspects can be found in many of the SC, bed type machines from their early history. That was the use of the curvic coupling for the turrets of those machines. This feature assured index accuracy and proper alignment with spindle nose and bed centerline 100%. This accuracy was achieved through the unique and patented design of the curvic coupling on the bottom of the turret and its mesh with the top of the carriage.
In essence, the curvic coupling was a ring of precision ground face splines which were meshed after index. The splines, or radial teeth, were ground in such a manner that on one member the sides of the teeth surfaces that meshed were convex and on the other member the sides were concave. The result was that after these members were clamped together, perfect index location was achieved, and further, the turret was perfectly on center.
Other, less expensive solutions were used by our competitors. The Hirth coupling, and various other "face gear" versions were used, but none of those alternatives worked as well as the W/S solution, featuring the Gleason curvic coupling. As I recall, we had at least two grinders kept busy in the production of these curvic couplings.
The other important advantage of the curvic coupling was that its accuracy in both axes actually improved with use, rather than being degraded. The only "trick" in their application was the necessity of guarding against the entry of chips or other debris into the seating area, W/S handled that part of their design very well also.
In essence, the curvic coupling was a ring of precision ground face splines which were meshed after index. The splines, or radial teeth, were ground in such a manner that on one member the sides of the teeth surfaces that meshed were convex and on the other member the sides were concave. The result was that after these members were clamped together, perfect index location was achieved, and further, the turret was perfectly on center.
Other, less expensive solutions were used by our competitors. The Hirth coupling, and various other "face gear" versions were used, but none of those alternatives worked as well as the W/S solution, featuring the Gleason curvic coupling. As I recall, we had at least two grinders kept busy in the production of these curvic couplings.
The other important advantage of the curvic coupling was that its accuracy in both axes actually improved with use, rather than being degraded. The only "trick" in their application was the necessity of guarding against the entry of chips or other debris into the seating area, W/S handled that part of their design very well also.