US1667006A - Lapping machine - Google Patents

Description

R. HOFSTETTER LAPPING MACHINE Filed June 27, 1925 April 24, 1928.

3 Sheets- Sheet 2 5 /n ve/vfor R. HOFSTETTER April 24, 1928.

LAPPI NG MACH I NE Filed June 2'7, 1925 3 Sheets-Sheet 3 //7 venfar floberfflolfsifier by Arfy Y provision of a machine of this character ping two surfaces simultaneouslg Patented Apr. 24, 19 28.

UNITED, STATES- PATENT OFFICE.

ROBERT HORSTE'ITEK OF BERWYN, ILLINOIS,

COMPANY, INCORPORATED, OF NEW YORK, N. Y.,

assmnon T0 wnsrnmr nLnc'rnIc a coaroanmon or mew YORK.

LAPPING MACHINE.

use... filed June 27, 1926. sem No. aaaeo.

Thisinvention relates to lappin or grinding machines, and more articular y to a machine for simultaneous y lapping opposite surfaces of a plurality of articles.

The primary object of this invention is the the lapping surfaces and carried by a memher which is relatively rapidly revolved and slowly reciprocated is a work carrying tray.

In order to facilitate the positioning of the,

articles to be lapped prior to the placement of the work carrier between the lapping surfaces, the tray is provided with members which permit the tray to be loaded independent of the lapping machine and during the process of lapping other articles. The mechanism for imparting the slowly reciprocating and rapidly rotating motion to the work carrier comprises a gear train which is connected to a source of motive power. The gear train is located just below the lower lapping surface and is protected from 'abrasive or other deleterious substances by a cover which also serves as a clutch plate for imparting motion to the work carrier along with a housing comprising a plurality of telescopic baflie walls. When the lapping operation is completed the upper lapping surface is moved with respect to the lower lapping surface in a manner such that means is effective for automatically removing any" articles which may have adhered to the upper lapping surface. I

Other objects and advantages of the invention will more'fully appear from the following detailed description taken in connec- 31 meshing with three eccentrlc pln gears 32 I tion with the accompanying drawings which illustrate several embodiments thereof,-.and

in which Fig. 1 is a fragmentary vertical sectional view of one type of lapping machine embodying the features of the invention;

Fig. 2 is a complete plan view thereof upon a reduced scale showing in dotted oute0 7 line the position 'of the upper lapping disk whenreplacing the same or reloading the machine with articles-to be lapped;

Fig. 3 is a plan view taken upon the line 3-3 of Fig. 1 showing the sub-plate or tray 66 in position;

Fig. 4 .is a

partly in elevation upon the line 4-4 thereof, and

Fig. 5 1s a fragmentary side view of 21.70

modified form of'the machine.

In the accompanying drawings the machine is shown as adapted to one specific use, that of lapping or grind faces of carbon and protector blocks used- "[6 ing opposite surextensively in the art of telephony, but it will be readily understood that the invention can be otherwise used and embodied.

Referring now to the-drawings in detail and particularly to Fig. 1, at 10 is shown the base of the machine upon which is journaled a worm shaft 11 which may be connected to any suitable source of power (not shown). The worm shaft 11 is in engagement with a worm wheel '12 keyed to a vertically disposed hollow shaft 13. At the lower end of the shaft 13 is secured a suitable combination radial and thrust bearing indicated at 16 which is supported in a stationary cap member 17 carried by the base 10. At. its upper end the shaft 13 is radially supported 111 a suitable journal provided in a gear housing 18 integral with a lap supporting member 19 secured to the base 10 asindicated at 20.

Within the bore of the hollow shaft 13 is a I fixed shaft 21, the upper end of which is suitably journaled in the shaft 13 and the lower end is provided with a reduced squared .portion 24 which fits within a similarly shaped opening 25 formed in a ring 26 secured to the stationarycap member 17 by dowel pins 27. Secured from rotation upon the upper end of the fixed shaft 21 by a pair of Woodrufi keys indicatedat 28 and from longitudinal movement thereon by suitable means comprising a spanner wrench screw indicated at 29 is a non-rotatable spur. gear (Figs. 1 and 3) freely rotatable upon studs fragmentary vertical section the u per end of the hollow rotatable shaft 13. pon an enlarged upper end of each of the gears 32 ,is suitably secured a disk 35 having an eccentrically formed raised portion 38. A'combined cover and clutch plate is indicated at 39 for supporting and glving motion to a work carrier 40 to be fully described hereinafter. Riveted to and depending from the underside of the clutch plate 39 are three pins 41 which. are arranged to freely enter suitable openings formed in the eccentrically disposed raised portions 38 of the disks 35 carried b the gears 32. Thus it will be seen that w mm the machine is in operation the work carrier 40 will be simultaneously. oscillated and rotated so that the articles being lapped will be moved between the lapping surfaces of upper and lower lapping plates 42 and 43 respectively whose opposing parallel faces constitute the lapplng surfaces.

Referring to Figs. 1, 3 and 4 the top surface of the. plate 39 is provided with six equally spaced depressions 44 of suitable depth and extending to the periphery of the plate Within which are entered teeth 45 s1m1 larly spaced upon the work carrier 40. The work carrier 40 comprises a thin plate pro- -vided with a central aperture 46 having the teeth 45 extending inwardly from the wall thereof. Secured to the underside of each of the teeth 45 by rivets 47 is a plate 48 having the same contour as the teeth 45 except for a lip portion 49 which extends beyond the wall of the aperture 46 as clearly shown in Figs. 3 and 4. The purpose of this lip willbe made apparent hereinafter. a

An im ortant feature of the invention is the provision of a construction whichserves to prevent the access of any abraslve ma, terial or particles from the lapped articles to the driving mechanism for the work carrier hereinbefore described. This construction consists in the following: V

As described hereinbefore the pins 41 are secured to the clutch plate 39 by riveting as clearly shown in Fig. 1 and the plate therei by forms a complete cover for protecting the actuating mechanism positioned therebelow from the deleterious effects of abrasives and other substances. This is accomplished since no openings or passages occur in the plate 39 which will permit any abrasive compound thrown upon the top surface of the plate 39 to seep through and reach the actuating mechanism. In addition to this cover plate ot er protecting means is provided as fol lows: Supported above the upper surface of the flange 34. of the hollow shaft 13 and the spur ear 31 by three equally spaced pins one of which is indicatedat 53 (Fig. 1) is a hood 54, a depending circular wall of which just clears the outside vertical circular wall' of the gear housing 18. Also suitably secured to the underside of the flange 34 is a I Lee-7,600

plate 39 the cooperating hood 54 and ring 55 and the walls 56 and 57 respectively and a circular depending wall 63 formed upon the plate 39 all abrasive material which in the majority of instances is powdered emery to which water is added durin the lapping operation and the dust resulting from the lapping operation is prevented from ainlug access to the gears and journals within the gear housing 18. The base 10 is provided with a cup like formation 64 for the purpose of catching all excess abrasive material thrown ofl by the machine and which material may be readily removed therefrom by first removing a guard ring 65 provided with a shouldered lower end which freely fits upon the vertical wall of the cup formation 64. i

The lap plates 42 and 43 are each in the form of a ring preferably composed of close grain cast iron and are identical in shape and adapted to be used interchangeably as the upper onlower lap. The lower lap plate 43 rests upon an upper surface 65 of the support 19 and is prevented from shifting there- I on by a pin 67 carried by the lap andengaging a vertical slot 68 in an upwardly extending flange of the support 19, as clearly shown in Figs. 1 and 3, At one side of the machine is a vertical post 69 (Fig. 2) supported for rotation upon suitable bearillgs (not shown) provided in the base 10. Adjustably attached to the upper end of the post 69 by any suitable means such as set screws is an over-hanging arm or bracket 70 which extends directly over the central 'portion of he base 10 and at its outer or free end is provided with a vertical opening 71. Reciprocally mounted within the opening 71 is a spindle 72 provided with a gear rack- 73 meshing with a pinion 74 carried by the arm 70 and arranged to be operated by a hand wheel 75 (Fig. 2) whereby the upper lap 42 may be raised from the work for the -purpose of inspection or reloading. Suitable means which may be a ratchet or latch (notnot sufficient a weight may be employed. To

the upper end of the spindle 72 a weight may be secured in any suitable manner, such acwelght being indicated in dotted outline at upper lap to adjust itself to an slight deviation from parallelism with t e lower lap that maybe caused by irregularities in the work before the lapping operation commences. A screw 79 threaded into the end of the spindle 72 with a washer intermediate the head of the screw and the spindle serves to retain the spider thereon. The upper surface of the spider is provided with ratchet teeth 82 which mesh with ratchet teeth provided on a collar 83 reciprocally mounted upon the spindle 72 by a suitable key and keyway indicated at 84. A compression spring 85 positioned around the spindle between a collar 86 fixed thereto and the collar 83 retains the teeth of the latter in mesh with the teeth 82. The purpose of this ratchet clutch will be made apparent hereinafter. Each arm 87 of the spider 78 is adapted at its free end ,by a pair of horizontally disposed pins 88 to support a clamping block 89, the pins 88 being fixed to the arm 87 and adapted to freely enter openings provided in the block. A removable pin 90 passing through a lip 91 extending from the arm 87 and into an opening formed in the block 89 intermediate the pins 88 serves to lock the block to the arm. Formed integral with each block is a'pin 94 adapted to enter openings 95 formed in the vertical peripheral wall of the lap plates 42 and 43 when'used as the upper lap, three openings 95 being provided in each lappla te. A knob 96 is secured to each block to facilitate the removal of the block from the arm 87. Thus it will be apparent'tha t a lap plate may be readily released from the spider 78 by first removing the pins 90 and then pulling the knobs 96 outwardly. At times it is desirable to use the lower lap as the upper one and vice versa. This it will be seen may be readily accomplished. The lap plates are each provided with centralapertures 97 of sumcient size to permit the reciprocation of the' clutch plate 39 carrying the work carrier 40.

The work carrier 40 referring to Figs. 3 and 4 is provided with a plurality of equally spaced openings 98 each adapted to hold a plurality of articles which may .be carbon protectorlblocks indicated at 99.

Another important feature of theinvention resides in providing means for facilitating the mounting of a loaded work carrier in operative position upon the lower lap, which means also permits an operator while one set v of articles is being lapped 'toreload another work carrier 40 with another set of articles which upon completion of the lapping of the first set and'the removal thereo from the machine may be immediately mounted in position, thereby reducing the ndn-productlve time of the machine to a minimum. This means comprises asub-plate or tray 104 which comprises two identical semi-circular shaped plates 105 which when brought together as illustrated in Fig. 3 form a rin of a diameter slightly greater than the wor carrier 40. Fixed to the to surface .of each of, and equally spaced therearound are a plurality of retaining lugs 106 each provided with a raised overhanging lip portion 107 clearly illustrated in Fig. 4. Each plate 105 is rovided with a handle portion 109 to facilitate the positioning thereof under the work carrier before loading the latter and the withdrawal therefrom upon positioning it from the lap plate. To load the work carrier the sub-plate or tray 104 is first secured thereunder by gripping the plates 105 by the handle portions 109 and slipping them into posltlon under the carrier until the inner edge of each plate rests upon the lip portion 49..of the plates 48 fixed to the carrier with the overhanging lip portion 107 of the with articles to be lapped and'thereafter the tray '104 may be raised by the handles 109 and. positioned upon the lowerlap plate 43 with the teeth 45 of the carrier entered within the depressions 44 of the clutch plate 39 (Figs. 3 and- 4) whereupon the; plates 105 are withdrawn from under thecarrier by simply pulling outwardly in opposite directions upon the handles 109, the carrier with the artlcles dropping downwardly upon the lap plate 43 as the plates 105 are withdrawn. Upon the completion of a lapping opera: tion the upper lap is raised in the manner hereinbefore explained by turning the hand wheel and swinging the upper lap to the position indicated in dotted outline in Fig. 2 thereafter the work carrier is removed by lifting it upwardly, the articles lapped being left upon the lower lap plate 43 and subsequently removed by brushing them into asuitable receptacle.

Another important feature of the invention is theprovision of means whereby any lapped articles adheringto the upper lap plate 105 adjacent theperip eral edge therello upon completion of the lapping operation (ill articles lap (1 will adhere thereto and if not remove a will not allow the lap plate to .be lowered into proper position upon starting another lapping operation thereby necessitating the raising of thelap again and the removal of the articles adherin thereto with a consequent delay in the comp etion of the lapping operation and output of the machine and frequently damaginga great number of the articles to be lapped. To insure the removal of any articles adhering to the upper lap there is provided a stationary wiper member 110, in the form of a rod suitably secured to the post 69 (Fig. 2) and projecting at right angles from the normal position of the arm 70 andat such a. level that upon swinging the lap plate 42 to the dotted outline position the lapping silrface of the plate 42 will just clearthe upper surface of the wiper. In this position the lap plate may be revolved around the wiper 110 'in a clockwise direction due to the ratchet clutch mounted on thespider 78 and spindle 72 as hereinbefore described. and any adhering articles will be brushed from the lap and into a suitable receptacle (not shown).

A modified form of the machine is illustrated in Fig. 5 wherein an air cylinder 111- may be suitably connected to a suitable source of air under pressure. Suitable control devices (not shown) are provided for raising and lowering the upper lap plate 42 and for applying pressure thereto when the machine is in operation instead of the rack and pinion and weights, respectively, used on the machine first described. Also instead of swinging the upper lap plate'42 horizontally to one side when removing'and loading the machine with articles to be lapped as hereinbefore described, the modified machine is provided with power driven mechanism for swinging verticallytheupper lap to the dotted outline position tFig. 5) in which mechanism is also embodied means whereby the" lap may be swung horizontally the machine first described. The frame 112 supports a bracket 113 to which is journaled a worm shaft 114 meshing with a mutilated worm wheel 115 freely rotatable upon a fixed shaft 116 carried by the bracket 113. The shaft 114 may be connected to any suitable source of power (not shown). Formed upon the worm wheel 115 are two projecting lugs 117 and 118 which serve to limit the angular movement of the lap plate 42 to 90 or. the movement between the full and dotted outline positions shown (Fig. 5), the lugs engaging either end of the worm upon the worm shaft 114. Suitably fixed to rotate with the worm wheel 115 is a bracket 119 provided at its upper end with a circular cup shaped portion 120 within whiclris fitted for rotation a depending flange like portion 121 of an overhangingarm 122 supporting at its free end the air 0 linder 111,' a piston rod 123 operated there y supporting the upper lap plate 42 by a floating conthe r rotation nection, and for permittin thereof as explained herein efore in connection with the other type of machine a ratchet clutch 126 is provided. The arm 122 is normally prevented from rotation upon the bracket 119 by a removable pin 127 passing through an opening provided in a retaining ring 128 fixed to the upper surface of the cup shaped portion 120 and into an opening provided in the flange like portion 121 of the arm 122. When it .is desired to swingthe upper lap 42 horizontally to one I side the pin 127 is simply removed and the I arm may be readily moved. The ring 128 serves to support' the arm 122 upon the bracket 119. A wiper member 130 is employed to remove any articles adhering to the upper lap 42 upon completion of a lapping operation in a manner similar to that described hereinbefore in connection with the first described embodiment of the in vention. The member 130 is positioned The stationary shaft 116 extends outside ofthe bracket 113 and has fixed to its end a bevel gear 131 which is in mesh with a second bevelgear 132 rotatably supported in any suitable manner upon a depending shaft 133 fixed to the cup shaped portion 120 ofthe br acket119. The member 130 is secured for rotation with the gear 132 and it will readily be seen thatupon a movement of the lap 42 to the indicated dotted position thereof that-the bevel gear 132 carried by the shaft 133 and rolling about the fixed bevel gear 131 will cause the wiper member 130 to be moved to the position indicated in dotted outline whereupon by revolving the lap 42 through the ratchet clutch 126 any adhering articles will be brushed from the l rom the foregoing description it will be seen that a lappin machine isprovided in which the several eatures and arrangement thereof combined provide means by which the production of lapped articles may be rapidly and economica ly produced.

Although the invention has been described with reference to the particular. construction of machine shown, it is obvious that loo Ill

rier in operative *position'relatir e to said plates comprising a sectional ring like mem-' ber adapted to be removed before the lapping operation 2 The combination of a lapping machine having upper and lower lapping plates mountable in operative position relative to each other, a work carrier mountable between said plates, means for providing a relative motion between said plates and carrier whereby lapping movements between the work and plates are accomplished, said carrier comprising a member'in the form of a' ring provided with a plurality of apertures for positioning articles to be lapped and provided adjacent its' inner, periphery with a plurality of radially projecting lugs spaced from the underside thereof, of means for loading and mounting. said carrier in operative position relative to said plates comprising a sectional ring like member arranged to be secured to the carrier at its inner periphery upon the lugs of the carrier and provided adjacent its outer periphery with a plurality of inwardly ex-- tending lugs adapted to engage theupper face of the carrier adjacent its periphery," the sections of said member adapted to be.- removed from the carrier before the. lap-' ping operation.

3. In a lapping machine, upperand lower lapping plates mountable in operative position relative to each other, a work carrier mountable between said plates, means" for providing a relative motion between said, plates and carrier whereby lapping movements between the articles and plates are accomplished, means to elevate and laterally move the upper plate, and means rendered effective upon the I elevation and lateral movement of the upper lapping plate for 3 removing adhering from. V

4. In a lapping-machine, upper and lower lapped articles there lapping plates mountable in operative position relative to each other, a work carrier mountable between said plates, means for providing a relative motion between said plates and carrier whereby lapping movements between the work and plates are accomplished, means to elevate and laterally move the upper plate, means associated therewith adapted to permit rotation of said plate, aiid means arranged to remove adhering lapped articles therefrom upon completion of the lapping operation by causing a rotation of said plate upon elevation and lateral movement of the same.

5. In a lapping machine, a' frame, upper and lower lapping plates mountable in operative position relative to each other, a 'work carrier mountable between said plates, means for providing a relative motion between said plates and carrier whereby lapping movements between the work and plates are accomplished, an arm carried by ,said frame adapted to swing in a vertical plane for supporting the upper plate, and vmotive fluid operated means for elevating said plate upon the arm and adding pressure thereto when in operative position.

6. In a lapping machine, upper and lower lapping plates mountable in operative position relative to each other, a work carrier mountable between said plates, a gear train positioned below said carrier and plates,

means for connecting said gear train tosaid carrier whereby lapping movements between the work and plates are accomplished,

said means comprising a plate spanning the gear train and providing a protecting cover therefor and provided at its peripheral upper edge-with depressions forming jaws adapted to operatively engage teeth projecting from a central aperture/formed in said carrier and means attached to the plate adapted to o'peratively connect with the gear train, said means being attached to the plate in such a manner that noabrasive material can 'reach said gear train,

17. In a lapping machine, an upper and lower lapping plate non-rotatably mounted when in lapping position, a work carrier, power driven means, and means "associated with said power driven means for communicating to said work carrier. reciprocatory and rotary motion, including a supporting member, depending portions integral there- In witness whereof, I hereunto subscribe my-name this 19 day of June A. D., 1925.

' ROBERT HOFSTETIER.

Images