US1925911A

US1925911A - Method of grinding crank shafts

Info

Publication number: US1925911A
Application number: US415836A
Authority: US
Inventors: Amos P Steiner
Original assignee: Landis Tool Co
Current assignee: Landis Tool Co
Priority date: 1929-12-21
Filing date: 1929-12-21
Publication date: 1933-09-05
Anticipated expiration: 1950-09-05

Description

Sept 1933- A. P. STEINER METHOD OF GRINDING CRANK SHAFTS Filed Dec. 21, 1929 INVENTOR Arno. F Jfe/ncr.

TTORNEY Patented Sept. 5, 1933 v UNITED STATES PATENT OFFICE 1,925,911 METHOD OF GRINDING CRANK SHAFTS Application December 21, 1929 Serial No. 415,836..

6 Claims. (Cl. 51-4578) This application is a division in part of the copending application of Amos P. Steiner, Paul Stoner, and Charles P. Harrison for crank grinding machines, Serial No. 126,583, filed August 2, 1926, and is directed to the method of grinding crank shafts. 7

An object of theinvention is to provide a method for grinding crank shafts in which all the pins on a shaft may be ground onone ma- 10 chine without changing the'set-upor arrange-.

ment of the fixtures.

In grinding crank shafts as heretofore practiced it was necessary to have a separate machine for each pair of pins, each machine was set-up to grind a certain pair of pins and could not be used for any other set without shifting the work rest around. In grinding crank shafts in large quantities, such as is necessary in modern mass production, such methods were costly and slow.

0 By moving the work rest from the work table where it has been heretofore placed and mounting it so that it will always be in grinding position, i. e. always in the plane of rotation of the grinding wheel, a set-up is provided which does not need to be changed at all so that all the pins on a shaft may be ground on a single machine. This results in a great saving in the handling of the work as Well as providing a great saving in-the number of machines as heretofore required.

My method consists in moving the work carriage so as to bring the pins into position between the wheel and a work rest. The work rest-and the wheel are moved against the pin which is in position; the pin is ground and the work rest and the wheel are returned to inoperative position so that the carriage may be moved between the work rest and the wheel to bring another pin on the crank shaft in the same plane into grinding position before the wheel. When all the pins in a single plane have been ground the work rest and the grinding wheel are withdrawn and the crank is indexed so as to bring another pair of pins in position to be ground. The crank shaft is held in chucks and is gripped at a point eccentric with respect to its axis of rotation so that the crank always rotates around an axis which is the axis of the pin which is being ground. Each pair of pins is ground and the shaft rotated to bring the adjacent pair to position until all of the pins are ground. After grinding each pin the work restand the grinding wheel are each withdrawn to permit the work carriage freely to pass between the grinding wheel and the work rest; the work rest being positioned in the plane of the, grinding wheel is always in position to hold a pin when the pin has been brought to. grinding position.

The drawing 'is a diagrammatic illustration of the various positions of the grinding wheel, the crankshaft and its pins and the back rest.

Referring to the drawing which is made a part hereof-and on which similar reference characters indicate similar parts,

Figure I shows a conventional grinding wheel anda crank shaft with pin 1 or 6 in grinding position,

Figure 1A is a plan view showing the grinding wheel and work rest in position to grind pin No. 7 1 on a crank shaft, Y

Figure 1B is a plan View showing the wheel and the work rest withdrawn to allow the crank shaft to be moved to bring pin No. 6 into grinding position,

Figure 10 shows the grinding wheel, the work rest and the crank shaft in position to grind pin No. 6 on the crank shaft,

Figure 2 'is a view in elevation of the grinding wheel and the crank shaft showing pin No. 2 or 5 in position to be ground,

Figure 2A shows the grinding wheel and work rest withdrawn to permit a crank shaft to be moved to position at which pin No. 2 may be ground,

Figure 2B shows the grindingwheel and back rest in position to grind pin No. 2,

Figure 2C shows the grinding wheel and the back rest withdrawn from pin 2 to permit traversal of the work carriage.

Figure 2D shows a grinding wheel and work rest in position to grind pin No. 5,

Figure 3 is an end elevation of the grinding wheel and crank shaft so as to show the relative positions of the grinding wheel and the 5 crank shaft when grinding either pin No. 3 or No. 4, a

Figure 3A shows the grinding wheel and the back rest withdrawn to permit traversal of the crank shaft to bring pin No. 3 in position to be ground,

Figure 3B shows the grinding wheel and back rest in position to grind pin No. 3,

Figure 30 shows the grinding wheel and back rest withdrawn to permit traversal of the crank shaft to position the grind pin No. 4.

Figure 3D shows the grinding wheel and back rest in position to grind pin No. 4, and

Figure 3E shows the grinding wheel .and parts withdrawn to permit the crank shaft to be withalways rotate about the pins which are beingound.

A grinding wheel 13 is mounted so as to move into and out of grinding position to grind the work and a work rest 14 is movable toward and from the work to hold the workagainst the grinding wheel.

As soon as a pin is ground to size the work rest and the grinding wheel are retracted and the work is traversed between them to bring the other pin in the same plane into position after which the grinding operation is repeated. I The long arrows 15. indicate the direction in which the work carriage and the crank shaft are about to move. The short arrows 16 and 17 indicate the directions in which the grinding wheel and'the work rest respectively have just moved. I

It will be obvious to those skilled in the art that various changes may be made in my device without departing from the spirit of the invention and therefore I do not limit myself to what is shown in the drawing and described in the specification, but only as indicated in the appended claims.

Having thus fully described my said invention, what I claim as new and desire to secure by Letters Patent, is:

1. The method of grinding the pins of multiple throw crank shafts which consists in grinding first the pin or pins in a given plane, rotat ing the shaft to bring other pin or pins into the axis of rotation of said pins, grinding the pin or pins while supporting said shaft against the thrust of the grinding action, withdrawing the support and the grinder sufficiently far from the shaft to permit free indexing of the shaft from the position for grinding one pin to the position for grinding another pin, all of the grinding being performed while maintaining a given grinding set-up of the machine, substantially as set forth. I

2. The method of grinding the pins of multiple throw crank shafts in a single machine which consists in grinding first the pin or pins in a given plane, rotating the shaft to bring other pin or pins into the axis of rotation of said pins, grinding the pin or pins while supporting said shaft against the thrust of the grinding action, withdrawing the support and the grinder sufficiently far from the shaft to permit free indexing of the shaft from the position for grinding one pin to the position for grinding another pin, all of the grinding being performed while maintaining a given grinding set-up of the machine, substantially as set forth.

3. The method of grinding the pins of crankshafts which consists in first grinding all pins which are in axial alignment with eachother, rotating the shaft through a partial revolution to bring another set of axially aligned pins into grinding relation with the grinding wheel, grinding this set of pins and then 'rotatingtheshaft to bring other sets 'of axially aligned pins into grinding relation with the grinding wheel and grinding them, grinding of all of said pins being accomplished while maintaining a given grinding set-up of -the machine, substantially as set forth.

4. The'method of grinding the pins of crankshafts in a machine having a wheel which comprises grinding one set of pins, rotating the shaft to another set of such pins and grinding them and continuing the rotation and the grinding of the several sets of pins, indexing the shaft axially between each grinding operation and withdrawing the back rest between each grinding operation sufficiently far to permit free rotation and free axial indexing of the shaft while maintaining the original grinding set-up" of the machine, substantially as set forth. v

5. The method of operating a grinding machine having a back-rest and a grinding wheel for grinding the pins of crankshafts which consists in grinding all of the pins in a given plane, rotating the shaft to bring a set of pins in another plane in correct rotary position for grinding them, grinding these pins, successively rotating the shaft to bring other sets of pins into grinding position and successively grinding them, withdrawing the back-rest a distance sufficient to permit freerotary and axial indexing of the shaft, grinding of the entire shaft being effected while maintaining a given grinding setup of the machine whereby all of the pins on a crankshaft may be ground by a single machine,

substantially as set forth.