Grinding machine and method of grinding
AssigneeUnova U K Ltd.
InventorMichael Laycock
Life of this patent
Estimating the term…
Abstract
An apparatus for, and method of, grinding crankpins of a crankshaft wherein the machine is under computer control and the grinding wheel is advanced and retracted under computer control so as to follow the planetary motion of the crankpin as the crankshaft rotates. This maintains grinding contact between the wheel and the crankpin to allow the grinding of the latter. The crankshaft is mounted between centers and is rotated by a drive unit, drive being transmitted to the end of the crankshaft via a connecting device which is torsionally rigid in a plane perpendicular to the axis of rotation of the crankshaft but which is readily deformable in other planes to accommodate misalingnment and so as to decouple the crankshaft from the drive other than to transmit pure rotation to the crankshaft.
Claims25
A grinding machine adapted to grind a crankpin region of a crankshaft by synchronously advancing and retracting a grinding wheel as the crankshaft is rotated so that contact is maintained between the grinding wheel and crankpin during grinding of the crankpin so as to grind a true cylindrical surface on the crankpin, comprising drive means for rotating the crankshaft, and a drive coupling means which is torsionally rigid in a plane generally perpendicular to the axis of the crankshaft but is readily deformable in other planes to accommodate misalignment for connecting the drive means to the crankshaft.
A grinding machine comprising a headstock and tailstock between which a crankshaft can be mounted for rotation between centres, means for drive the crankshaft and means for coupling the drive means thereto in a manner as to remove errors due to offset and misalignment, a grinding wheel which can be advanced and retracted towards and away from a crankshaft, when the latter is mounted in the grinding machine, and aligned with a crankpin thereof, and a computer for controlling the said advance and retraction of the grinding wheel thereby to cause the latter to advance and retract in synchronism with the planetary motion of the crankpin as the crankshaft rotates, so as to maintain grinding contact between the grinding wheel and the crankpin at all time during the grinding of the crankpin.
A method of grinding a crankpin of a crankshaft by a synchronously controlled grinding wheel while the crankshaft is mounted between centers, the crankshaft having a main axis of rotation and including a circular flange at one end, comprising the steps of:
- (a.) providing a rotational drive;
- (b.) providing a coupling that is torsionally rigid in a predetermined plane but which is readily deformable in other planes to accommodate misalignmemt;
- (c.) mounting the crankshaft between the centers;
- (d.) attaching radially outer regions of the circular flange to said rotational drive to rotate the crankshaft about the main axis of rotation through said coupling and so that said predetermined plane is perpendicular to the main axis of rotation of the crankshaft;
- (e.) advancing the grinding wheel to engage a crankpin of the crankshaft;
- and
- (f.) synchronously controlling the position of the grinding wheel while the crankshaft is rotated to follow the planetary motion of the crankpin so as to maintain grinding contact between the grinding wheel and the crankpin.
A method of grinding a crankpin with a crankpin axis radially offset from but substantially parallel to a main axis of a crankshaft, the crankshaft being mounted for rotation between centers and being driven through a coupling mechanism that removes errors due to offset and misalignment during the grinding process and so as to rotate about the main axis of the crankshaft, wherein a rotating grinding wheel is advanced and retracted, under computer control and in synchronism with planetary rotation of the crankpin to be ground caused by rotation of the crankshaft, so as to maintain grinding contact between the grinding wheel and the crankpin at all times during grinding of the crankpin.
Dependencies are inferred from the claim text.