US2359969A

US2359969A - Grinding machine

Info

Publication number: US2359969A
Application number: US449035A
Authority: US
Inventors: William L Carson
Original assignee: Washington Iron Works Inc
Current assignee: Washington Iron Works Inc
Priority date: 1942-06-29
Filing date: 1942-06-29
Publication date: 1944-10-10
Anticipated expiration: 1961-10-10

Description

Oct. 10, 1944.

W. L. CARSON GRINDING MACHINE 4 Sheets-Sheet 1 Filed June 29, 1942 INVENTOR ATTORNEY Oct. 10, 1944. w CAVRSQN 2,359,969

GRINDING MACHINE Filed June 29, 1942 4 SheetS -Sheet s I E I ATTOR/VEY Oct. 10, 1944. w. L CARSON GRINDING MACHINE 4 Sheets-Sheet 4 Filed June 29 1942 Patented Oct. 10, 1944 GRINDING MACHINE William L. Carson, Seattle, Wash, assignor 'to Washington Iron Works, Seattle, Wash., a corporation of Washington Application June 29, 1942, Serial No. 449,035

16 Claims.

This invention relates to radial grinding machines, and for its objectaims to provide an extremely eflicient machine for precision-grinding concentric surfaces and one, more especially,

which is self-feeding for imparting a predetermined and selectively variable axial advance to the grinding tool at cyclic intervals.

It'is a further object of the invention to provide a radial grinding machine embodying devices performinga stop function automatically limiting the cyclic feed movement to a predeter- -mined maximum-of axial travel.

With the foregoing and still further objects and advantages in view, the invention consists chine embodying my improvements and having parts shown fragrnentarily and other parts broken away and shown in horizontal section.

Fig. 2 is aside elevational view thereof shown partly in longitudinal vertical section and delet-- ing the drive motor and the double-rack gear which function to impart a reciprocatory swinging movement to the tool-carrying beam.

Fig. 3 is a fragmentary horizontal section on line 33' of Fig. 2. r

Fig. 4 is a view in elevation of the end proper of the swinging beam and its supported tool.

Fig. 5 is a viewtaken to an. enlarged scale and illustrating, in top plan, the shear-pin assembly employed to drive-couple the swinging beam to a drive bracket driven from the double-rack gear. I

Fig. 6' is a verticalsectional view on line 6-6 of Fig. 5.

Fig. 7 15a fragmentary longitudinal vertical section to-an enlarged scale detailing the transmission mechanism which operates to impart a cyclic feed to the grinding tool.

Figs. 8 and 9 are transverse vertical sections on the respective section lines 8-8 and 95 of Fig. '7; and

Fig. 10 is a fragmentary end view taken to an enlarged scale andirom a direction opposite to that-of Fig. 8 to further detail the lost-motion drive which characterizes my feed mechanism, the parts being shown in positions different from that of Fig. 8.

In said drawings, the numeral llindicates the swinging beam of my machine, and I2 a pedestal ;post upon which the same is journaled and which is rigidly bolted to a bed plate l3, the bed plate also acting as a footing for a clamped work-piece which I have designated by the letter W. Formed upon the top and bottom of the beam to extend along a side edge thereof are-a rail l4 and a complementing flared tongue l5, and tracking thereon for movement longitudinally of the beam is a carriage [6. Received in a side channel of the beam and held against end movement in bearing blocks |'I--l8 is a feed-screw 20, and working on the screw is a walking nut 2| secured tothe carriage. A controlling crank handle for the screw is indicated at 22.

Said carriage, upon its outer face, provides a pair of spaced apart vertical ribs l6 which act in complement to describe a dove-tail tongue. Formed with a correspondingly shaped grove to slidably workupon this tongue, there is provided a plate 23 which carries a stud bolt 24 fitted with a locking nut25, and mounted thereon is a grinding head 26 tiltably adjustable about a lrorizontal axis tangential to a circle taken about the center of the journal post [2 as an axis. The grinding head is self-contained, which is to say that the same mounts an electric motor 21 and a tool supporting arbor, as 28, having constant-drive connection with the motor. 28 indicates the grinding tool.

From the foregoing, it'will be understood that the grinding head is adjustable toward and from the swinging axis of the beam by means of the,

longitudinal slide, and is also adjustable for leadnamely in a direction longitudinally of the axis of the post l2by means of the vertical slide, and for accomplishing this latter function I employ a bell-crank assembly built up from separate lever arms which are keyed to a common fulcrum pin 30 journaled transversely through the upper extension of the carriage. -One of these lever arms, as 3|, connects by a link 32 with the plate 23, and the other lever arm, as 33, is or may be furcate in form and connects by parallel linkage 34 with trunnionposts provided upon opposite sides of. a feed-screw nut 35. The feed-screw for this nut is designated by 36 and at its outer end finds a bearing in an extension N5 of the carriage, the opposite or innerend being received through an automatic intermittent-feed transmission which will be hereinafter described. There is provided a crank handle 31 for manually settingthe feed-screw; and hung from an arm 38 which is or may be integral with the lever arm 33 is a counter-weight 3%.

Considering now the drive for swinging the beam in its reciprocatory movement, the invention employs a drive bracket 40 journaled upon a skirt dependency H of the beam and formed with a radial arm in which is a longitudinal slot 4|. Fixed to the bracket in adjusted relation longitudinally of the slot, thereby to regulate the swinging arc of the beam, is a wrist pin 42 which connects with a driving arm 43, the driving arm having fixed to its underside a double-rack driving gear 44 driven from a pinion 45, and the pinion being driven through suitable reduction gearing from an electric motor 46. Between the drive bracket and the beam is a drive coupling including a shear-pin. 41 and, to the end of adapting such pin to repeated usage, the same is given a slide fit for axial take-up in a sleeve 48. The sleeve is socketed in a bearing 49, and carries a draw-pin 50. While I have indicated this draw-pin as serving the added end of a set-screw for the shear-pin, a separate screw for this purpose is preferably applied in countersunk relation to the sleeve at the lower end of the latter.

Reverting to the feed-screw and describing the intermittent-feed transmission hereinbefore mentioned, it will be seen that a sector bevel gear 5| is rigidly clamped upon the upper end of the journal post l2, and that a hollow bevel pinion 52 is journaled in a beam-carried bearing 53 to mesh therewith. Finding a revoluble mounting within the pinion and projecting forwardly therefrom is a sleeve 54, and mounted upon the forward projection of the sleeve is a disc 55 formed with a peripheral lug 55' arranged to be driven through a lost-movement drive from a driving disc 56 fixed to the pinion. This lost-movement drive is comprised of a pair of driving dogs 5158 clamped in adjusted positions upon the rim of the driving disc, with one of the dogs acting to engage and drive the driven lug in one direction of the pinions rotary movement and the other dog operating in the return movement of the pinion to drive the lug in the opposite direction of rotation with the lost motion corresponding to the spacing which obtains between the driving faces of the two dogs. From the driven disc the drive is carried through a reversible pawl 60 to the teeth of a ratchet gear 5| which, like the driven disc, is freely revoluble upon the sleeve 54. Indicated .by 64 is a leaf spring functional to the pawl for yieldingly depressing the selected pallet 60' or 60", as the case may be, into operative driving relation to the ratchet gear. This said ratchet gear is produced as an integral part of the driving element of a jaw-clutch assembly including a driven element 62, and characterizing this driven element is the fact of the same being produced as a split bronze ring fitted with a tightening screw 63 for adjustably drawing the same down upon a collar 65 for obtaining a friction drive between the clutch and the collar, the collar being keyed as at 66 to the sleeve 54. The feed-screw 31 is received through and driven by the sleeve while being permitted relative sliding movement to compensate for radial adjustment of the grinding head. While not illustrated, the free end of the spring 64 has its underside transversely notched at a point which, by engagement with the peaked back of the pawl, holds the latter in neutral position permitting the operator to manually set the grinding tool at the desired initiating point of a grinding operation by the use of the crank handle 31.

It is believed to be readily understood that the described friction drive from the bronze ring $2 to the collar 65 permits the former to slip upon the latter in the event of there being developedin the course of the tool feed-a resistance of suiiicient intensity to overcome the draw adjustment of the screw 63, and I utilize such slippage as a means for controlling the maximum travel of the grinding tool in its cyclic feeding movements. To this end I fixedly mount a vertical screw 57 upon the slide plate 23, and provide thereon a pair of knurled adjusting nuts 68- 38 to have the latter lie at opposite sides of and be brought by vertical movement of the grinding tool into engagement with a stop lug 10, the stop lug being fixed to the carriage [6.

The operation of the automatic feed may be explained as follows: The operator determines the lead desired in a cycle of the beams reciprocatory swinging movement, and clamps the driving dogs 5!-58 upon the rim of the driving disc 56 in correspondence therewith. There is of course interdependence between the location of the driving dogs and the swinging arc of the beam from the fact that the degree to which the beam is caused to swing by the setting of the wrist pin 42 in relation to the longitudinal slot 4i governs the number of teeth of the sector gear meshed by the pinion 52, and by such token the portion of a turn which is given to the pinion. The selected pallet of the reversible pawl 60 is brought into engagement with the ratchetgear 6|, according as to whether the work feed is to move upwardly or downwardly over the precision surface of the work-piece, and the related adjusting nut 68 or 68', as the case may be, is threaded into such position upon the fixed screw 6'! as to be brought into engagement with the stop lug 10 upon completion of the desired feed movements. The

motors

21 and 46 are then energized, whereupon the revolving tool is caused to swing in reciprocatory travel over the precision surface of the work-piece, the pinion 52 imparting lost-motion responsive movement through the. driving dogs of the driving disc 56 to the pick-up lug of the driven disc which acts in turn to impart unidirectional rotary movement through the pawl-ratchet-clutchfriction drive elements 60-6|-6265 to the feed-screw 31 which, through the nut 35, connecting linkage 34, bell-crank lever 3I-33, and link 32, slides the grinding head verticallythe movement being intermittent and occurring in each like directional swing of the beam. The manner in which the feed movements are caused to progress only to a predetermined maximum or limit of travel with a resulting slippage of the friction-drive ring upon the collar as the related nut68 or 68is brought into engagement with the stop lug 10 is thought to be clear,

It is believed to be self-evident that the functional teachings of the invention lend themselves to operations other than grinding, and it is therefore intended that the term grinding as used in the description and claims will be construed as including other applicable operations excepting in such instances as the express language describing parts peculiar to a grinding tool permits of no other interpretation. Departures from the illustrated and described embodiment will suggest themselves, and I accordingly expect that the hereto annexed claims be read with only such limitations as are necessaril introduced thereto to distinguish from prior knowledge in the art.

What I claim is: r

1. In a radial grinding machine, in combination with a grinding tool and a tool mount: a

swingably mounted beam; power devices having operative connection with the beam for recipalleling the swing aXis of the beam; and mechanism functional to the tool mount and operat 'ing automatically in response to the cyclic swing of the beam to intermittently advance the tool mount upon its support for imparting progressing lead movements to the tool.

2. In a radial grinding machine, in combination with a grinding tool and a tool mount: a

'swingably mounted beam; power devices operative to reciprocally swin the beam; means provided upon the free end of the beam supporting the tool mount for sliding movement in a direction paralleling the swinging axis of the beam; and intermittently acting mechanism operating automatically in response to the cyclic swing of the beam for advancing the tool mount progressively upon its support, said mechanism including a feed-screw functional to the tool mount and a pawl-driven ratchet wheel operative to the feed-screw and itself operated from the swinging movement of the beam.

3. The combination of claim 2 providing adjustablc stop devices for limiting the travel of the tool mount upon its slide, and having a fric- "tion-drive connection from the ratchet wheel to the feed-screw acting by slippage to relieve the feed-screw of the driving influence of the ratchet wheel. upon a travel of the tool mount to a predetermined end limit of slide movement.

4. In a radial grinding machine, in combination: a swingably mounted beam; power devices carriage and having connection with the grinding head for advancing the latter upon its supfiort; and mechanism operating automatically in response to the cyclic swing of the beam for inter- -mittently imparting functional movement to the feed-screw.

5. A grinding machine according to claim 4 in which the grinding head is self-contained to provide a grinding tool and an electric motor for driving the tool movably bodily in relation to the carriage.

6. A grinding machine according to claim 4 in which the power devices for reciprocally swinging the beam are comprised of a driving bracket coupled to the beam and providing a radial extension, a mangle rack having radially-adjustable wrist connection with the radial extension, and a motor-driven pinion meshing the teeth of the mangle rack.

7. In a radial grinding machine, in combination: a swingably mounted beam; power devices operative to impart reciprocatory swinging movement to the beam; a grinding head; a beam carried carriage supporting the grinding head for sliding movement in a direction paralleling the swinging axis of the beam, and itself supported for sliding movement longitudinally of the beam; means for manually setting the carriage in relation to the beam for governing the radial swing for reciprocally swinging the beam and including a motor-driven drive bracket supported for reciprocating movement about an axis coinciding with that of the beam; a retractible pin for releasably coupling the bracket to the beam; a grinding head slidably supported upon the free end of the beam for sliding movement in a direction paralleling the swinging axis of the beam; and intermittently acting mechanism operating automatically in response to the cyclic swing of the beam for advancing the grinding head progressively upon its slide.

9. In a radial grinding machine, in combination: a swingably mounted beam; power devices for reciprocating the beam; a grinding head slidably supported upon the iree end of the beam for sliding movement in a direction paralleling the swinging of the beam; a feed-screw supported by the beam and having connection with the grinding head for advancing the latter upon its support; adjustable stop devices for limiting the travel of the grinding head upon the slide; a ratchet wheel; means responsive to the cyclic swing of the beam for imparting intermittent and uni-directional turning movements to the ratchet wheel; and a friction-drive connection between said ratchet wheel and the feed-screw acting normally to transm t the turning movements of the ratchet wheel to the feed-screw, said connection being operative by resistance-developed slippage to relieve the feed-screw of the driving influence oi the ratchet wheel upon a travel of the grinding head to a predetermined end limit oi slde movement.

30. In a radial grinding machine, in combination: a swingably mounted beam; power devices in relation to the beam for governing the radial swing of the grinding head; a feed screw carried y the carriage to lie in radial relation to the beam and having connection with the grinding head for advancing the latter progressively upon its support; and means operating automatically in response to the cyclic swing of the beam for mparting intermittent turning movements to the feed-screw, said means comprising a fixedly mounted gear disposed to lie in concentric relation to the swinging axis of the beam, a pinion meshing the teeth of said gear, a ratchet wheel, a reversible pawl driven from the pinion and operating to transmit uni-directional turning movements to the ratchet wheel, and connection from the ratchet wheel to the feed-screw for rcsponsively turning the latter.

11. A radial grinding machine according to claim 10, said pinion, the ratchet wheel and pawl assembly, and the connection from the ratchet wheel to the feed-screw being mounted directly upon the beam in co-axial relation to the feedscrew, and wherein the feed-screw is slidably reeived through the same to compensate for sliding movement of the screw-supporting carriage longitudinally of the beam.

12. In a radial grinding machine, in combination: a swingably mounted beam; power devices for reciprocating the beam; a beam-carried grinding head supported for sliding movement in a direction paralleling the swinging axis of the beam; a feed-screw carried by the beam; connection from the feed-screw to the grinding head functioning to. advance the head progressively upon its support in response to turning movements of the screw; and means including a fixedly mounted sector gear disposed concentric to the swinging axis of the beam and an intermittentfeed transmission actuated therefrom in response to cyclic swing of the beam for turning the screw, said intermittent-feed transmission being carried by the beam and comprising a pinion meshing the teeth of the sector gear, a drive disc revoluble with the pinion and provided upon its rim with peripherally spaced driving dogs, a driven disc provided with a peripheral pick-up lug arranged to lie in the space between and receive a lostmotion drive from the driving dogs, a ratchet wheel, a reversible pawl carried by the driven disc functioning to transmit uni-directional turning movements to the ratchet wheel, and connection from the ratchet wheel to the feed-screw for responsively turning the latter.

13. In a radial grinding machine, in combination: a swingably mounted beam; power devices for reciprocating the beam; mechanism for adjusting the swinging arc of the beam; a grinding head supported upon the free end of the beam for sliding movement in a direction paralleling the swinging axis of the beam; a feed-screw carried by the beam; connection from the feed-screw to the grinding head for advancing the latter progressively upon its support in response to turning movements of the screw; and means for turning;

the screw in response to cyclic swing of the beam including a fixedly mounted sector gear disposed to lie in concentric relation to the swinging axis of the beam and an intermittent-feed transmission carried by the beam and actuated from said sector gear, said intermittent-feed transmission comprising a pinion meshing the teeth of the sector gear, a drive disc revoluble with the pinion and provided upon its rim with peripherally spaced driving dogs, a driven disc provided with a peripheral pick-up lug arranged to lie in the space between and receive a lost-motion drive from the driving dogs, a ratchet wheel, a reversible pawl carried by the driven disc functioning to transmit uni-directional turning movements to the ratchet wheel, and connection from the ratchet wheel to the feed-screw for responsively turning the latter.

14. A grinding machine according to claim 3' in which the driving dogs are adjustable peripherally upon the drive disc.

15. In a radial grinding machine, in combination: a swingably mounted beam; power devices for reciprocating the beam; mechanism for adjusting the swinging arc of the beam; a carriage mounted for longitudinal sliding movement upon the beam; a grinding head supported by the carriage for sliding movement in a direction paralleling the swinging axis of the beam and comprised of a tool-supporting arbor and an electric motor therefor movable slidably as a unit upon the carriage; means for manually setting the carriage in relation to the beam for governing the radial swing of the grinding head; a feedscrew supported by the carriage; a walking nut threaded upon the screw; connection from the walking nut to the grinding head for progressively advancing the latter upon its support in response to turning movements of the screw and comprised of a bell-crank having link-connection from one of its lever arms to the nut and from the other lever arm to the grinding head; and means for turning the screw in response to the cyclic swing of the beam including a fixedly mounted sector gear disposed to lie in concentric relation to the swinging axis of the beam and an intermittent-feed transmission carried by the beam and actuated from said sector gear, said intermittent-feed transmission comprising a pinion meshing the teeth of the sector gear, a drive disc revoluble with the pinion and provided upon its rim with circumferentially spaced driving dogs, a driven disc provided with a peripheral pick-up lug arranged to lie in the space between and receive a lost-motion drive from the driving dogs, a ratchet wheel, a reversible pawlcarried by the driven disc functioning to transmit unidirectional turning movements to the ratchet wheel, and connection from the ratchet wheel to the feed-screw for responsively turning the latter.

16. As a' power-transmitting assembly: the combination of a rotary drive member arranged and. adapted to be driven in opposite directions of rotation alternately; a power-transfer wheel; a reversible ratchet drive from the drive member to the wheelfor giving intermittent uni-directional movement to the wheel in either direction of rotation, selectively; a rotary driven member; stop means for positively limiting the rotational movement of said driven member; and a friction drive from the wheel to the driven member for driving the latter through the permitted range of the driven members movement, the cessation of movement of the driven member upon the exercise of said stopping function of the stop means causing slippage in the friction drive between said wheel and the driven member.

' WILLIAM L. CARSON.