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US 4,292,766 AGranted
Method and apparatus for grinding a workpiece
AssigneeThe Warner & Swasey Company
InventorsCalvin K. Kirk, Glover C. Joyce, Francis L. Messier
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AssigneeThe Warner & Swasey Company
InventorsCalvin K. Kirk, Glover C. Joyce, Francis L. Messier
Estimating the term…
An improved grinding method and apparatus is advantageously used to sequentially grind the pins of a crankshaft. During the grinding of each crankpin, the pin is supported by a steadyrest. During an initial grinding operation, the crankpins are measured or gauged to determine if they are out-of-round by an amount which is greater than the tolerances for the finished crankshaft and less than a maximum amount. If a crankpin is out-of-round by an amount which is equal to or greater than a maximum amount, the crankshaft is rejected. However, if a crankpin is out-of-round by an amount which is less than the maximum amount and more than the tolerance for a finished pin, a second grinding operation is initiated after the initial grinding operation has been completed. During the initial and second grinding operations, a main drive motor is effective to press the steadyrest against the crankpins. A secondary drive motor is provided to adjust the position of the steadyrest to compensate for the smaller size to which the crankpins are ground during the second grinding operation. The finished crankshaft is removed from the grinding machine only after both the initial and second grinding operations have been completed. When the number of consecutive out-of-round crankpins and/or crankshafts becomes excessive, a control signal initiates shutting down of the grinding machine and the establishing of an alarm to prevent the grinding of a large number of out-of-round crankshafts.
An apparatus for use in grinding a plurality of crankshafts each of which has a plurality of crankpins, said apparatus comprising holder means for holding each of the crankshafts in turn during an initial grinding operation and during a second grinding operation when one of the crankpins on a crankshaft is out-of-round by more than a first distance and less than a second distance at the end of the initial grinding operation, grinding wheel means for grinding each of the crankpins on each of the crankshafts in turn during the initial grinding operation and for grinding each of the crankpins on a crankshaft when a second grinding operation is necessary, first means for detecting when the number of consecutive crankshafts requiring a second grinding operation exceeds a predetermined number, and second means connected with said first means for initiating a control function upon detection by said first means that the number of consecutive crankshafts requiring a second grinding operation exceeds the predetermined number.
An apparatus for use in grinding a plurality of crankshafts each of which has a plurality of crankpins, said apparatus comprising holder means for holding each of the crankshafts in turn during an initial grinding operation and during a second grinding operation when one of the crankpins on a crankshaft is out-of-round by more than a first distance and less than a second distance at the end of the initial grinding operation, grinding wheel means for grinding each of the crankpins on each of the crankshafts in turn during the initial grinding operation and for grinding each of the crankpins on a crankshaft when a second grinding operation is necessary, first means for detecting when the number of consecutive crankpins requiring a second grinding operation exceeds a predetermined number, and second means connected with said first means for initiating a control function upon detection by said first means that the number of consecutive crankpins requiring a second grinding operation exceeds the predetermined number.
A method of grinding a crankshaft having a plurality of spaced apart crankpins, said method comprising the steps of mounting the crankshaft in a grinding machine, operating the grinding machine to sequentially grind each of the crankpins in turn during an initial grinding operation, engaging each of the crankpins in turn with a support surface on a steadyrest during the initial grinding operation, terminating the grinding of each of the crankpins in turn during the initial grinding operation with the support surface on the steadyrest a first distance from the central axis of a crankpin, determining that at least one of the crankpins is out-of-round by more than a second distance and less than a third distance at the end of the initial grinding operation, after completing the initial grinding operation performing the step of operating the machine to sequentially grind each of the crankpins during a second grinding operation, engaging each of the crankpins in turn with the support surface on the steadyrest during the second grinding operation, terminating the grinding of each of the crankpins in turn during the second grinding operation with the support surface on the steadyrest closer to the central axis of a crankpin than the first distance by an amount equal to a predetermined fourth distance which is at least as great as the third distance, and removing the crankshaft from the grinding machine only after having performed the initial and second grinding operations.
A method of grinding a plurality of crankshafts each of which has a plurality of spaced apart crankpins, said method comprising the steps of sequentially mounting each of the crankshafts in a grinding machine, operating the grinding machine to sequentially grind the crankpins on each of the crankshafts in turn during an initial grinding operation, determining when one of the crankpins on a crankshaft is out-of-round by more than a first distance and less than a second distance at the end of the initial grinding operation, after completing the initial grinding operation on a crankshaft having a crankpin which is out-of-round by more than the first distance and less than the second distance performing the step of operating the machine to sequentially grind each of the crankpins on that crankshaft during a second grinding operation, removing each of the crankshafts in turn from the grinding machine, said step of removing each of the crankshafts in turn from the grinding machine including the step of removing each of the crankshafts upon which initial and second grinding operations are performed only after having performed both the initial and second grinding operations, detecting when the number of consecutive crankshafts requiring a second grinding operation exceeds a predetermined number, and initiating a control function upon detection that the number of consecutive crankshafts requiring a second grinding operation exceeds the predetermined number.
A method of grinding a plurality of crankshafts each of which has a plurality of spaced apart crankpins, said method comprising the steps of sequentially mounting each of the crankshafts in a grinding machine, operating the grinding machine to sequentially grind the crankpins on each of the crankshafts in turn during an initial grinding operation, determining when one of the crankpins on a crankshaft is out-of-round by more than a first distance and less than a second distance at the end of the initial grinding operation, after completing the initial grinding operation on a crankshaft having a crankpin which is out-of-round by more than the first distance and less than the second distance performing the step of operating the machine to sequentially grind each of the crankpins on that crankshaft during a second grinding operation, removing each of the crankshafts in turn from the grinding machine, said step of removing each of the crankshafts in turn from the grinding machine including the step of removing each of the crankshafts upon which initial and second grinding operations are performed only after having performed both the initial and second grinding operations, detecting when the number of consecutive crankpins requiring a second grinding operation exceeds a predetermined number, and initiating a control function upon detection that the number of consecutive crankpins requiring a second grinding operation exceeds the predetermined number.
A method of grinding a plurality of crankshafts each of which has a plurality of spaced apart crankpins, said method comprising the steps of sequentially mounting each of the crankshafts in a grinding machine, operating the grinding machine to sequentially grind the crankpins on each of the crankshafts in turn during an initial grinding operation, said step of operating the grinding machine during each of the initial grinding operations including the steps of operating a first motor to move a support surface on a steadyrest through a first distance toward the central axis of each of the crankpins in turn and maintaining a second motor in a nonoperating condition through each of the initial grinding operations, determining when one of the crankpins on a crankshaft is out-of-round within a predetermined range of dimensions at the end of the initial grinding operation, and after completing the initial grinding operation on a crankshaft having a crankpin which is out-of-round within the predetermined range of dimensions performing the step of operating the machine to sequentially grind each of the crankpins on that crankshaft during a second grinding operation, said step of operating the grinding machine during the second grinding operation including the steps of operating the first motor to move the support surface on the steadyrest through the first distance and operating the second motor to move the support surface on the steadyrest through a second distance to thereby move the support surface on the steadyrest through a combined distance equal to the sum of the first and second distances.
Dependencies are inferred from the claim text.