US1184905A - Automatic reversing machanism. - Google Patents

Description

A. WHITE. AUTOMATIC REVERSING MECHANISM.

APPLICATION FILED JAN- B, [915- Patented May 30 1916. 2 SHEETS-SHEET 1.

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AUTOMATIC REVERSING MECHANISM.

APPLICATION FILED JAN. 8, 1915- L]. M $72 ess e S- .w e.

ARTEB MACHINE COMPANY, OF WORCESTER, MAEiSACHUSETTS, A CORPORfiTlON MASSACHUSETTS.

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Application filed January e, 1915.

State of Massachusetts, have invented certain new and useful Improvements in Automatic Reversing Mechanisms, of which the following description, in connection with the accompanying drawings, is a specification, like reference characters on the drawings indicating like parts in the several figures.

This invention relates to reversing mechanisms such, for instance, as those employed to control the movement of the Work holding table of a metal planing or grinding machine,

The invention has among its objects to devise a mechanism of this general character which shall be more positive in its action, more convenient to adjust, and less liable to get out of order, than those now used.

The invention will be readily understood from the following description, when read in connection with the accompanying drawings, in which- I Figure 1 is a front elevation of a mechanism embodying the invention; Fig. 2' is a vertical, sectional view on the plane indicated by the line 2-2, Fig. 1; Fig. 3 is a front elevation showing, on an enlarged scale, a portion of the mechanism shown in Fig. 1; Fig. 4 is a front elevation of an adjustable dog employed to operate the reversing mechanism; Fig. 5 is a vertical, sectional view on the plane indicated by thellne 5-5, Fig. 4; and Fig. 6 isa rear elevation of the plunger used in the dog shown in F1gs. 4 and 5.

Referring now to' the drawings, 2 indicates the frame or bed of a machine, such for instance as a grinder or planer, provided on its upper face with horizontal ways on which slides a table 4 that is designed to carry the work. This table is reciprocated on its ways to present different portions of the work tothe operation of the grinding or other tool. For this purpose a rack 6 is secured rigidly to the bottom of the table extending parallel to the ways on which the table slides, and a pinion 8 meshes with this rack and is mounted on the upper end of a vertical shaft 10 supported in suitable bearings in the frame 2. Mounted on the shaft 10 Specification of Letters Patent.

Patented May 34), With.

Serial No. 1,146.

isa toothed clutch sleeve 12 keyed to the shaft but slidable longitudinally thereof into or out of engagement with a similar toothed sleeve 14 that rotates loosely on the shaft 10 and forms the hub of a worm wheel 16. In order to move the sleeve 12 into or out of engagement with its cooperating. sleeve 14, a collar 18 is formed on the sleeve 12 and is grooved to receive a pair of rolls 19 and 20 mounted on the forked end of a lever 22 which is fulcrumed on the machine frame at The "forward end of this lever is positioned within convenient reach of the operator.

The worm wheel 16 is driven by a worm 24 which is fast on one end of a shaft 25 mounted to rotate in a long bearing formed in one part of a gear casing 26 that is bolted to'the sideof the machine frame 2. A large bevel gear 27 is mounted on the forward end of the shaft 25 and within the casing 28. Themain driving shaft 28 of the machine is mounted in bearings formed in the casing 26 and has secured thereto a series of pulleys 29 by means of which the machine may be belt connected to any convenient source of power. Within the casing 26 the shaft 28 supports two bevel gears 30 and 31, respectively, which are arranged to mesh with the bevel gear 27 at opposite points in its periphery. Both of these gears 30 and 31 are loose on the shaft 28 and the adjacent ends of their hubs are toothed. A sleeve 32, mounted on the shaft 28 between the gears 30 and 31, and splined to said shaft but slidable thereon, has its opposite ends toothed to mesh with the teeth on the respective gears 30 and 31. Accordingly, when this sleeve is moved into engagement with either one of the bevel gears 30 or 31, it will cause the gear so engaged to rotate with the shaft 28 and this rotative motion will be transmitted to the bevel gear 27 and through the shaft25, worm 24, Worm wheel 16, the clutch members 12 and 14 (assuming them them to be in engagement) shaft 10-, pinion 8 and rack 6, to the table 4. T he direction of this motion will depend on which of the gears 30hr 31 is driving the bevel gear 27.

' rocate longitudinally inbearings formed in th'ecasing 26. This rod 36 has pinned to it at-opposite ends of the shoe'34 two stop collars 38 and 39, respectively. When the rod 36, carrying the stops or collars 38 and 39 and the shoe 34, is moved far enough in one direction or the other to efiect a driving engagement between the clutch sleeve 32 and one of the gears 30 or 31, it is locked in that position, by one member of a pair of pawls 40 and 41, pivoted, respectively, near the opposite ends of the rod 36, the pawl 40 being arranged to engage with the collar 38, and the pawl 41 with the collar 39. Two springs 42 and 43 connected to the respective' pawls 40 and 41 serve to retain them yieldingly in locking engagement with their respective collars.

The pawls 40 and 41 may be released from locking engagement with their respective collars by means of a lever 44 fulcrumed on the upper part of the casing 26 and having a handle that projects above the level of the work table 4 and a part projecting below the fulcrum and carrying a pin 46 that lies between adjacent ends of the pawls 40 and 41. The ends of these pawls lie close to each other and are curved upwardly, as shown clearly in Figs. 1 and 3, so that, when the pin 46 is swung into engagement with either pawl, it will lift it out of engagement with its cooperating stop collar 38 or 39.

Pivoted to the rear face of the lever 44, and just below the fulcrum of said lever, are two arms indicated at 48 and 49. which bow out away from each other, then curve inwardly and downwardly toward each other again, terminating in ends that lie on opposite'sides of a pin 50 that projects rearwardly from the shoe 34. The pin 46 extends through the end of the lever 44 and the portion of the pin 46 that projects from the back of the lever 44 also lies between the ends of the arms 48 and 49 and just above the pin 50. A coiled spring 52 has its ends connected to the bowed portions of the arms 48 and 49 and tends to keep the free ends of the arms 48 and 49 in contact with the pins 50 and 46.

While the lever 44 may be moved in either direction by hand. ordinarily this movement is effected automatically by adjustable dogs mounted on 'the table 4. .A dog of novel construction is provided by this invention. In the arrangement shown, a rack 54 is secured to the edge of the table 4. the teeth of this .rack projecting downwardly. The dog has a body 56 straddling the rack 54 and designed to slide freely along the rack. This body 56 is drilled vertically to receive a plunger 58 which has a flat face 59 (see Fig. 6) designed to slide along the plane side of the rack 54, and is provided at its lower end with a small toothed stop 60, the teeth of the stop being shaped to fit into the teeth of the rack. At its upper end the plunger 58 has secured thereto a cap 62 which is of larger internal diameter than the plunger, thus providing an annular place around the plunger in which is seated a coiled spring 6.4. that bears against the inner face of the cap and the top of a boss 66 formed integral with the body 56 and on which boss the cap 62 slides. In other words, the cap 62 forms a housing or inclosure for the spring 64.

It will be evident from an inspection of Figs. 4, 5 and 6 that the spring 64 normally presses the, plunger 58 upwardly and holds the teeth of the part 60 in mesh with the teeth of the rack 54, thus locking the dog against movement longitudinally of the rack. When it is desired to adjust the dog it is merely necessary to depress the plunger sufficiently to move the teeth 60 out of engagement with the teeth of the rack and then to slide the dog along the rack the required distance. This construction prevents the entrance of dirt into the moving parts, is very easily operated and since the teeth of the rack project downwardly they cannot get filled up with chips or other foreign material.

A stop 68 is pivoted to the body of the dog 56 on a screw 69 and the forward depending end of this stop is positioned for engagement with a pin 0 projecting from the rearward side of the lever 44. The rack 54of course carries two dogs 56, one on each side of the lever 44, one of these dogs serving, by the engagement of its stop 68 with the pin 70, to move the lever 44 in one direction and the other to move the lever in the oppositedirection. In order to obtain a finer adjustment of the stop with relation to the table 4 than could be made by means of the plunger 58, the part 56 has projecting therefrom an ear 72 through which is threaded an adjusting screw 74 arranged to bear against the back of the stop 68 and to swing this stop more or less about its pivot 69 to give any required adjustment of thestop. A look nut 76 serves to hold the set screw 74 in adjusted position.

It is sometimes necessary to lift the stops 68 into such a position that they will clear the pin on the lever 44 and in order to permit the workman to make this adjustmentv and leave his hands free for other work, a friction device is provided to hold the stop yieldingly in any position to which it may.be moved. This device consists in theconstruction shown of a spring 78 seated in a small hole formed in the body 56 of "the dog and a ball 80 that is pushed against the rear face of the stop 68 by the spring 7 S. This arrangement affords suflicient friction to hold the stop 68 in any position of adjustment to which it may be moved with reference to the body 56. i

It will now be clear that, when the main shaft 28 is being driven, if the lever 44 is swung out of its neutral position far enough to cause the clutch sleeve 32 to engage one of the gears 30 or 31, the table will be moved along its ways through the connections previously described. Assuming the lever to have been thrown to the'right as the parts are seen in Fig. 3, thus moving the clutch sleeve 32 into engagement with its cooperating clutch part formed on the gear 31, as shown in said figure, the table will be moved from right to left. The pawl 40 at this time will be in engagement with the stop collar 38, thus'holding the parts 31 and 32 in operative engagement. When the table has moved to a point predetermined by the adjustment of the right hand dog 56, as the parts appear in Fig. 1, the stop 68, carried by the dog, will strike the pin 70, thus swinging the lever 44 toward the left and moving the pin 46, mounted on the lower end of the lever, toward the pawl 40. The spring 52, acting through arms 48 and 49, tends to hold the pin 50 in line with the fulcrum of the lever 44 and the pin 46 and, consequently, normally tends to hold the clutch sleeve 32 in an intermediate or neutral position between the gears 30 and 31 where neither gear will be driven. Since the shoe 3% controls the position of the clutch sleeve 32, it controls the direction of movement of the table 4:.

. The initial movement of the lever 44, as above described, to render operative the gear 31 tensions the spring 52 in a direction tending to move the clutch sleeve 32 back toward its neutral position. The movement of the lever 44 produced by the dog 56, as

entire operative portion of the spring 52 just described, further tensions this spring 52 in the same direction since the pin 46, in swinging toward the pawl 10, moves the arm 48 in acounter clock-wise direction, as the parts are seen in Fig. 3. Consequently, as soon as the pin 46 has been moved far enough to release the pawl 40 from engagement with the collar 38, the spring 52 then operates through the arm 49, the pin 50 and the shoe 34 to slide the clutch sleeve 32 out of engagement with the gear 31 and into engagement with the gear 30." The latter gear then becomes operative to drive the table 4 in a direction opposite to the direction in which it has just been driven by the gear 31. The pawl 41, by its engagement with the collar 39, holds the clutch 32 in operative engagement with the gear 30. The

which in the present instance includes all of the spring between the pins on which it acts, is effective to shift the shoe 3d, and consequently the clutch sleeve 32, from either one of its operative positions to the other.

- When the dog 56 at the left of the lever 44: strikes the pin and swings the lever 4:4: to the right again, the spring 52 will be tensioned in a direction opposite to that in which it has just acted, the pawl 41 will be lifted and the sleeve 32 will be moved by the spring 52, operating through the arms 48, into engagement with the gear 31. This cycle of operations will be repeated until interrupted by moving the clutch sleeve 32 through the means of the lever 4st into a neutral position or by the interruption of the driving connections between the gear 27 and the table 4. by depressing the forward end of the clutch lever 22 and throwing the clutch members 12 and, 14 out of engagement with each other, One advantage of this arrangement is that the same spring effects the shifting of the sleeve 32 in both directions, thus avoiding a diliiculty which has heretofore been experienced with similar mechanisms in which independent springsare used to throw the clutch part in opposite directions and in which it was found that the reversing mechanism often failed to work due to one spring being stronger than the other. The present mechanism also is of advantage because of the saving in parts which it efiects.

Having fully described my invention, what 1 claim as new and desire to secure by Letters Patent of the United States is:

1. In a machine of the character described, the combination with a driving shaft and a reciprocatory table, of means arranged to be operated by said shaft for giving said table a reciprocating movement, a reversing mechanism controlling the operation of said means, said mechanism comprising a device for controlling the direction of movement of the table and movable from one position to another to effect a re versal of the movement of the table, means for locking said device temporarily in either of said iositions, a tension spring connected with sald device to move it from either one of said positions to the other, the same portion of said spring being operative to move said device in-both directions, and means operative at predetermined points in the stroke of the table to release said locking means whereby said spring will move said device from one of said positions to the other. 7

2.- In a machine of the character described, the combination with a driving shaft and a reciprocatory table, of means arranged to be operated by said shaft for giving said table a reciprocating movement, a reversing mechanism controlling the operation of said means, said mechanism comprising a device for controlling the direction of movement of the table and movable from one operative position to another to effect a reversal of the movement of the table,

. tension the-entire operative portion of'said spring in a direction depending on the direction of movement of the table and to release said locking means, whereby said spring will move said device fromone of its' 0 erative positions to the other.

3. n a machine of the character described, the combination with a driving shaft and a reciprocatory table, of two members arranged to be driven by said shaft and having connections with said table enabling them to drive the table in opposite directions, a clutch device arranged to occupy a neutral position or to be moved into different operative positions to render one or the other of said members operative to drive said table, and means for operating said device comprising a tension spring, means operated by said spring to hold said device yieldingly in its neutral position, means for locking said device in either of its operative positions, and means operated by the table for tensioning the entire operative portion of said spring alternately in opposite directions and then releasing said locking means to permit said spring to move said device from one operative position to another.

4. In a machine of the character described, the combination with a driving shaft and a reciprocatory table, of means arranged to be operated by said shaft for giving said table a reciprocating movement, a reversing mechanism controlling the operation of said means, said mechanism comprising a device for controlling the direction of movement of the table and movable from one operative position to another to effect a reversal of the movement of the table, means for locking said device temporarily in either of its operative positions, a tension spring, means connected with the opposite ends of said spring for transmitting the action of said spring to said device, and mechanism operative at predetermined points in the stroke of said table to tension said spring in a direction depending on the direction .of movement of said table and to release said locking means, whereby said spring will operate through said transmitting means to move said device from one of its operative positions to the other. i

. 5. In a machine of the character described, the combination with a driving shaft and a reciprocatory table, of a pair of gears arranged to be driven by said shaft and having connections with said table enabling them to drive the table in'opposite directions, a clutch device mounted for movement into either of two positions operative teeth and operating to render one or the other of said gears able arms operatively connected with said device to movethe device from one position to another, a spring connecting said arms and tending to hold said device in a neutral position, means for locking said device temporarily in either of its operative positions, and a lever arranged to be oscillated by said table and operating through said arms to tension said spring in either direction and thereafter to release the locking means to permit the spring to move said device from either of its operative positions to the other.

6. In a machine of the character described, a table, a rack secured to said table with its teeth projecting downwardly, a dog slidable on said rack, and means carried by said dog operative through engagement with the teeth of said rack to lock said dog against movement along the rack and to be released again to permit the adjustment of the dog along the rack.

7. In a mechanism of the character described, a rack supported with its teeth projecting downwardly, a dog slidable on said rack, a device constructed to interlock with the teeth of said rack, said device being carried by said dog but movable relatively thereto into or out of engagement with said to hold the dog against movement along t e rack when in engagement with said teeth, and means for normallyholding said device in locking engagement with the teeth of said rack.

8. In a mechanism of the character described, a rack supported with its teeth projecting downwardly, a dog slidable on said rack, a plunger vertically movable with relation to said dog and rack but slidable with said dog, said plunger being provided with a part constructed to interlock with the teeth of said rack, and a spring operating on said plunger to hold said part normally in engagement with said teeth.

9. In a mechanism of the'character described, a rack supported with its teeth projecting downwardly, a dog slidable on said rack, a plunger mounted in said dog to slide therewith but movable vertically in said dog, said plunger having a art arranged to interlock with the teeth of Said rack when the plunger is raised, a cap fast on the upper end of said plunger, and a spring-between said cap and dog operating to hold the plunger yieldingly in its raised position,

. said cap being shaped to inclose said spring.

10. In a mechanism of the character described, an adjustable dog, a stop su ported by said do for adjustment re tively thereto, and riction means for holding said stop yieldingly in an adjusted position with relation to said dog.

11. In a machine of the class described, the combination of a driving shaft, a reciprocating table, reversing mechanism, connections between said shaft and table controlled by said mechanism for driving the table, a dog adjustably mounted on said table, said reversing mechanism including a member arranged to be operated by said dog, a stop pivoted on said dog for movement into or out of position to engage said member and a friction device interposed between adjacent surfaces of said dog and stop opera- 10 tive to hold the stop yieldingly against movement relatively to the dog.

In testimony whereof I have aflixed my signature in presence of two Witnesses.

ALPHONZO WHITE. Witnesses:

WILLIAM ARTER, JOHN H. MOCREADY.

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