US2287449A - Wheel speed control - Google Patents

Description

June 23, 1942. R. E. PRICE 2,287,449

WHEEL 'SPEED CONTROL -Filed Nov. a, 1940 v s sheets-sheet 1 Gttorneg y June 23, 1942. R. E. PRICE 3 Sheets Sheet 2 Filed Nov. 8, 194g June 23, 1942. R. E. PRICE: 2,287,449

WHEEL SPEED CONTROL Filed Nov. 8, 1940 3 Sheets-Sheet 3 *u uw? I L RALPH .E 'Pla/es Gttomeg Patented June 23, 1942 WHEEL SPEED- coN'rnoE Ralph E. Price, Highfield, Ma., assigner-t Landis Tool Company, Waynesbormla.

Application November s, 1949,5serg`ia1NogVs-c4,g9z2

4 claims. (ci. 51-166i wheel. In this latter case the intention was that as the wheel became smaller and had to move farther to engage the work, each increase in forward movement would be utilized to advance the rheostat and increase the speed of the Wheel drive motor. This method had the disadvantage that each time the Wheel was backed off, the setting of the rheostat was also changed and the speed' of the wheel reduced One method of overcoming this difculty Was to provide a lost motion device in the connection between the wheel support and the rheostat so that the rheostat would not be affected by the back off movement of said support.

It is an object of this invention to provide means for controlling the wheel speed which will not require a lost motion device.

A further object is to provide means whereby the speed control means will be actuated by the wheel adjusting mechanism.

In the drawings:

Figure 1 i's a plan view of a grinding' machine to which my invention is applied.

Figure 2 is an end elevation showing the connection between the feed mechanism and the wheel motor control rheostat.

Figure 3 is a partial front elevation in section on line 3-3 of Figure 2 showing the method of mounting my device.

Figure 4 is a sectional plan view of the feed mechanism and speed control device.

Numeral I0 indicates the bed of a grinding machine, in this case a multiple wheel grinder for grinding line bearings of crank shafts, cam shafts, and similar Work. Numeral II is the wheel support, I2 indicates the several Wheels rotatably mounted thereon, and I3 an adjustable speed motor for driving said wheels. A work carriage I4 slidably mounted on bed I0 has mounted thereon a headstock I5 and a footstock I6 having work supporting centers I1 and I8 respectively.

The means for moving said Wheels toward and from the work consists of a piston 30 in a cylinder 3| in bed I0. Said piston is attached to a feed shaft 32 having a threaded portion 33 and. a splined portion 34. A nut 4U on said threaded portion is attached to Wheel support II by means of a bracket 4I. Forward movement of the feed shaft and piston is limited by a positive stop 42.

Said feed shaft 32 may be rotated to provide a grinding feed movement by a mechanism consisting of a worm wheel 50 slidably mounted on the splined portion 34 of said feed shaft. A worm 5I engages said worm Wheel. Said worm is carried on a shaft 52 which may be shifted endwise by a piston 53 in a cylinder 54. Said endwise movement' may be controlled by causing said shaft 52 to engage a dash pot mechanism 55.

Said feed mechanism may also be actuated manually. Shaft 52 has a splined portion 56 on which is mounted a bevel gear 51. Said bevel gear engages another bevel gear 58 on shaft 59.`

Shaft 59 is rotated by a suitable mechanism driven manually by handwheel 60.

Surface speed of the wheels I2 may be held constant as the wheels wear down by a mechanism consisting of a rheostat 10. An arm 1I for' actuating same is mounted on a shaft 12 which is rotatably supported in a bracket 13 attached to bed I0. Another arm 14 attached to said shaft has a hardened shoe 15 for engaging the peripheral surface of a cam 16. Said cam is adjustably attached to shaft 11 of a speed change mechanism 18. A second shaft 19 of said speed change has a sprocket attached thereto. A chain 8| connects said sprocket with another sprocket 82 on manually rotated shaft 59. The rheostat shown is a special type and requires special mechanism for operating it. Obviously any standard rheostat or any type of speed control mechanism may be used in connection with the speed reduction unit 18.

I claim:

1. In a grinding machine, a work support, a wheel support, a grinding wheel rotatably mounted thereon, means for driving said wheel, a speed control means therefor, mechanism for effecting a relative transverse positioning and feeding movement between said supports, mechanism operableV independently of said positioning mechanism for effecting -a relative adjusting movement between said supports for changing the zone of operation of said positioning movement as the wheel becomes smaller due to Wear and dressing, and a mechanism actuated by said adjusting mechanism for operating said speed control means.

2. In a grinding machine, a bed, a work support, a wheel support, a grinding wheel rotatably mounted thereon, means for driving said wheel, a speed control means therefor, mechanism for effecting a relative transverse positioning and supports for rst positioning said wheel and a work piece in operative relation and then continuing said transverse movement at a slower grinding rate, manually operated mechanism for changing the zone of action of said wheel support as the wheel becomes smaller due to Wear and dressing, and connections between said manually operated mechanism and said motor speed control mechanism 4. In a grinding machine, a bed, a work support, a grinding wheel support, a grinding wheel rotatably mounted thereon, means for driving said wheel, a speed control device for said driving means, manually operated means for effecting a relative adjusting movement between said supports as the wheel becomes smaller due to Wear and dressing, mechanism operable independently of said adjusting mechanism for effecting a relative transverse positioning movement between said supports, and connections between said adjusting mechanism and said speed control mechanism for changing the wheel speed to correspond to change in diameter thereof.

RALPH E. PRICE.

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