US2241351A

US2241351A - Lapping machine

Info

Publication number: US2241351A
Application number: US329592A
Authority: US
Inventors: Herbert S Indge; Franklin E Johnson
Original assignee: Norton Co
Current assignee: Saint Gobain Abrasives Inc
Priority date: 1940-04-15
Filing date: 1940-04-15
Publication date: 1941-05-06
Anticipated expiration: 1958-05-06

Description

y s. INDGE m1. 2,241,351

LAPPING MACHINE Filed April 15, 1940 s Sheets-Shet 1 HERBERT 5. INIDGE FRANKLIN E. JOHNSON May 1941- v H. s. lN DGE ETAL 2,241,351

LAPPING MACHINE Filed April 15, 1940 3 Sheets-Sheet 2 i 7' 1 I w 7 1 I85 50 jvwenvtdm HERBERT 5. INJJEE FRANKLIN E. l-JUHNSUN haw mean, WW

Patented May 6, 1941 LAPPIN MACHINE Herbert s. Indge, Westboro, and Franklin E. Johnson, Worcester, Mass., assignors to Norton Company, Worcester, Mass, a corporation of Massachusetts Application April is, 1940, Serial No. 329,592

14 Claims.

The invention relates to lapping machines, and more particularly to an automatically actuate and controlled lapping machine.

One object of the invention is to provide a simple and thoroughly practical automatic lapping machine. Another object of the invention is toprovide a lapping machine in which the approaching movement between the lapping elements is automatically and electrically con,- trolled.

Another object of the invention is to provide an automatic work loading device whereby a plurality of work pieces may be simultaneously moved into and away from an operative position before and after a lapping operation. A further object of the invention is to provide a plurality of work loading devices for simultaneously load- ,ing work pieces in a substantially radial direction into an operative position between the lapping wheels.

A further object of the invention is to provide a. hydraulically operated control system for moving the upper lapping wheel to and from an op eraltive position and to simultaneously actuate a,

trical control mechanism A further object of th invention is to provide.

a pressure controlling apparatus for automatically controlling the lapping pressure between the lapping wheels and the work to be lapped whereby either a uniformpressure may be obtained during the entire lapping operation or an initial lapping operation at one pressure for a definite time interval, after which the pressure is automatically changed to a second predetermined pressure for a. lapping operation. Other objects will be in part obvious or in part pointed out hereinafter.

The invention accordingly consists in the features of construction, combinations of elements, and arrangements of parts, as will be exemplified in the structure to be hereinafter described, and the scope of the application of which will be indicated in the following claims.

In the accompanying drawings, in' which is shown one of the various possible embodiments of the mechanical features of this invention,

Fig. l is a side elevation of the improved lapping machine, having parts broken away and 'shownin section to more clearly show the construction;

Fig. 2 is a. combined diagrammatic showing of the electrical and hydraulic control and actuatin sys e Fig. 3 is a fragmentary cross-sectional view through the machine, taken approximately on the line 3-3 of Fig.- 1, showing the work loading devices and cage in plan view;

Fig. 4 is a fragmentary sectional view, on an enlarged scale, of one of the work loading units as shown in Fig. 1;

Fig. 5 is a fragmentary sectional view, on an enlarged scale, through one of the work loading devices, taken approximately on the line 5-5 of Fig. 1; I

Fig. 6 isa fragmentary sectional view taken approximately on the line 66 of Fig. 5;

Fig. 7 is a fragmentary sectional view taken approximately on the line 'l--'l of Fig. 6; and

I Fig. 8 is a fragmentary sectional view, on an enlarged scale, taken approximately on the line 88 of Fig. 1, showing the bracket for supporting the cage.

Referring more particularly to the embodiment illustrated in the drawings, a lapping machine may be constructed in its general aspects similar to the lapping machine illustrated in the prior U. S. Patent to Indge, No. 2,103,984 dated December '28, 1937. This machine, as illustrated,

may comprise a base It) which rotatably supports a lower lapping wheel I l. The base I0 is provided with an upwardly extending column [2 having an outwardly extending horizontal arm I 3 whichrotatably supports a vertical spindle M.

The spindle It carries a rotatable lapping wheel l5 which is connected to the'spindle II by means of a supporting plate I6.

Power may be obtained from any suitable source, such as an overhead drive shaft or an electric motor mounted on the machine. For the sake of illustration, a belt drive, has been shown comprising a driving belt I! which serves to rotate a pulley I 8. The pulley I8 is supported on and arranged to rotate a. horizontally extending shaft I!) which is supported in bearings 20, 2|, 22 and 23 in the base It]. If desired, a manually operable clutch may be provided similar to that illustrated and described in my prior U. S. patent No. 2,103,984. This feature has not been illustrated in-the present. case since it is not considered to be a part of the present invention.

1 The shaft I9 is provided with a worm 25 which meshes with a worm gear 26 mounted on the lower end of a vertically arranged rotatable shaft 21. The shaft 21 is connected by a universal joint 28 with a shaft 23. The shaft 28 is preferably a telescopic shaft and is connected by a universal joint 38 with a vertical shaft 3|. The shaft 3| is supportedin

bearings

32 and 33 which are in turn supported in a bracket 34 mounted on top of the column. I2. The bracket 34 is preferably adjustably mounted .on the upper surface of the column. I! and is provided with a screw adjustmen't comprising a. screw 35 which is rotatably supported in a bracket 36 fixed to'the upper surface of column l2 and is screw threaded into the bracket 34 so that the bracket 34 may be adjusted transversely relative to the column. l-2

for the purpose of adjusting the tension of the belt drive to be hereinafter described.

This lapping machine is particularly adapted for the lapping of taper rollers. The lower lapping wheel H is provided with a frusto-conical operative-face whereas the upper lapping wheel I6 is provided with a plane operative face. The included angle betweenanelement of'the operativeface of the upper lapping wheel l and an element of the frusto-conical operative face of the lower wheel II is equal to that of diametrically opposed elements of the conical roller surface to be lapped. In such a machine,'it is desirable to impart a rotary motion to the lower lapping wheel II which in turn serves as a rotating and lapping element for a plurality of spaced The spindle I4 is eccentrically mounted within arotatable sleeve 48. The sleeve 48 is'in turn rotatably supported by bearings 4| and 42 which are carried by a vertically movable sleeve 43. It will be readily apparent from the foregoing disclosure that a rotary motion may be imparted to the spindle l4 and a rotary motion may be simultaneously imparted to the sleeve 48; .This .combined rotation of the spindle I4 and sleeve 48 serves to impart a combined rotary and planetary or gyrating movement to the upper lapping wheel IS.

The shaft 3| is provided with a multiple V-groove pulley 45 which is connected by V-belts 46 with a multiple V-groove pulley 41. The pulley 41 is fixedly supported on a sleeve 48 which is in turn rotatably supported in a bearing 49 which. is carried by the housing 58. ing 50 also surrounds and supports the vertically desired driving tension. It will be readily apparent from the foregoing disclosure that the driving belts 46 serve to produce a rotary motion of the sleeve 48 which in turn transmits a plane'- tary, or gyrating movement to the upper lapping wheel l5 and at the same time the driving belt 56 imparts a rotary motion to the upper lapping wheelspindle l4 to produce a combined rotary and planetary or gyratingmovement 'of the upper lapping wheel l5 relative to a plurality of work pieces located therebeneath.

It is desirable to provide a counterbalance mechanism for the upper lapping wheel assembly to counterbalance the weight of the upper lapping wheel and its supporting and actuating parts. The vertically movable sleeve 43 is pro vided with a. rack bar which meshes with a gear 66 rotatably supported on a shaft 61. The shaft 61 also supports a sprocket 68 which is connected by a link chain 68 with a counterbalance weight 10 in a manner similar to that shown and described in my prior U, S. Patent 6 No. 2,103,984, to which reference may be had for details of disclosure not contained herein.

A rotary motion is imparted to the lower lapping wheel II by means of a driving mechanism connected with the main drive shaft I9. A worm I5 is mounted on the drive shaft l9 and meshes with a worm gear 16 which is mounted on the lower end of a driving sleeve 11. A driving plate or spider I8 is mounted on the upper end of the-sleeve 11 and serves as a support for the lower lapping wheel' II. It will be apparent from the foregoing disclosure that when the shaft I8 is rotated, a rotary motion will be imparted through the mechanism just described to rotate the lower lapping wheel H and simultaneously therewith a combined rotary and gyrating or planetary movement will be imparted to the upper lapping wheel l5.

In order to limit the relative approaching movement between the lapping elements; a suitable stop mechanism is provided. As illustrated, a stop mechanism is provided comprising a stop abutment 88 which is supported by the housin 58 which is formedintegral with the column I2 and horizontal portion l3. A bracket 8| is adjustably supported on the vertically movable sleeve 43. The bracket 8| carries an adjustable stop screw 82 which is arranged to move in the path of the fixed stop 88 to limit the downward I movement of the sleeve-43 and thereby limit the The housmovable sleeve 43. The sleeve 48 'is connected by relatively long keys 5| with the keyways 52 and 53, respectively, formed in the peripheral surface adjacent to the upper end of the sleeve 40. By

7 provided to maintain the driving belt 56 in the approaching movement of the lap l5 relative to the lower lap II. By adjusting the position of the stop screw 82 relative to the bracket 8| and also by adjusting the position of the bracket 8| relative 'to the vertically movable sleeve 83, the stopping of the approaching movement of the lapping wheels may be varied as desired to facilitate lapping work pieces to the required extent.

In order to obtain the desired lapping action between the opposed lapping wheels II and I5 as the work is moved into operative position therebetween. it is desirable to provide an actuating mechanismv for causing the lapping elements to approach and recede from each other either during each lapping operation or to move thelapping elements into a fixed position while work pieces are fed intermittently into the throat formed between the operative faces therof. In

certain operations it is desirable to start the lapping operation at one, pressure to cause the rough lapping of the work piece and then to reduce the pressure between the lapping elements for a finish lapping operation.

A fluid pressure mechanism is provided for causing a relative approaching and receding movement between the lapping elements In order that a uniform pressure be applied to'the upper lapping elements so thatt-the lappinigsun' facethereof will remainjiri lane normal its axisof rotation, a pair of di metrically pp d fluid pressure cylinders 90 and 9| are mounted in position on diametrically opposite sides of the spindle housing 50. The cylinders 90 and 9| are provided with pistons 92' and 93, respectively. The pistons SI and 92 are connected by piston initial lapping operation, the solenoid I26 may be energized to maintain the valve I25 in the position illustrated in Fig. 2. After a predetermined time interval the solenoid I26 may be delief valve I2I operative. If the valve I2I is set

rods

94 and 95 with a flanged plate 96 which is j mounted on the lower end of the vertically movable sleeve 40. The flanged plate 06 is connected to the lower end of the sleeve 40 adjacent to the mounting plate I6 of the upper lapping wheel I5 so that when pressure is applied to the diametrically arranged pistons, the pressure is uniformily distributed over the entire surface of the upper lapping wheel andthere is no tendency on the part of the lap to assume other than a plane normal to its axis of rotation and revolution, thus minimizing any errors in the lapping operation due to lost motion between the lapping wheel I5 and its supporting parts.

Fluid for the pressure system is supplied from a reservoir I which is preferably located within the base I0 of the machine. Fluid is conveyed from the reservoir I00 through a pipe IN by means of a motor driven fluid pressure pump I02 which forces fluid through a pipe I03 to a main control valve I04. The valve I04 is of a balanced piston type comprising a valve stem I05 having formed integrally therewith valve pistons I06,

I01 and I08. In the position shown in Fig. 2,

fluid under pressure passing through the pipe I03 enters a valve chamber located between the valve pistons I01 and I08 and passes out through a pipe I09 which is connected by pipes II 0 and III to admit fluid simultaneously to cylinder chambers H2 and II3, respectively. The admission 01' fluid under pressure to the cylinder chambers H2 and I I3 causes a downward movement of the

pistons

92 and 93, respectively, to produce a downward approaching movement of the upper lapping wheel I5. During the downward movement, of the upper lapping wheel I5, fluid within cylinder chambers H4 and H5, respectively, exhausts throughv a pipe H6 and out through a valve chamber located between the valve pistons I06 and I0! and passes through a pipe III which exhausts into the reservoir I00.

An adjustable pressure relief valve 8 is connected by a pipe- 9 withthe pressure pipe I03. The relief valve II8 may be adjusted to maintain a desired operating pressure within the fluid system. When. pressure within the fluid system increases above the set pressure, the valve 8 opens .and passes excess fluid under pressure through an exhaust pipe I into the reservoir I00. If desired, a second pressure relief valve I2I may be provided which may be set at a different operating pressure from. the valve H3. The valve I2I is connected by a pipe I22 with a manually operable shut-off valve I23 which is in turn connected by means of a pipe I24 with'a piston type control valve I25. The control valve I25 is actuated by means of 'a solenoid I26. In

" the position of the valve I25 as illustrated, the

fluid under pressure passing through the pipe I03 does not enter the valve I25.

If it is desired, a relatively high pressure may be provided at the start of the lapping operation by adjustment of the valve H8. During the for a lower operating pressure than the valve H8, then the valve I2I will control the pressure within the'fluid system. If preferred, the valves 8' and I 2| may be manipulated so that, if desired, the lapping operation may be started at a low pressure and the pressure then increased as the lapping operation proceeds, or a single pressure may be utilized during the entire lapping operation. I

The valve I04 may be operated manually by means of a manually operablecontrol lever I30 which is supported on a rock shaft I3 I The rock shaft I3I also supports a rock arm I32 which is connected at one end to the valve stem I05 by means of a stud I33. In order to balance the weight of the lever I30- and the valve, a counterbalance weight I34 is connected to the opposite end of the rock arm I32. By adjusting the weight I34, the valve may be balanced so that it may be moved readily manually or electrically. A spring I34 is interposed between a stud projecting from the rock arm I32 and a stud I35 which is fixed to the casing of the valve I04. The spring I34 normally serves to hold the valve I04 in an uppermost position, that is, in a position so that fluid is admitted through the pipe II6 to tween the lapping wheels II and I5, respectively.

p m (Fig. 5).

A plurality of work loading devices are'arranged about the periphery of the lapping wheels which are arranged in close relationship with each otherintermittently to move work pieces in a substantially radial direction into an operative position between the lapping wheels.

A pan-shaped member I40 is mounted on the machine base I0. A plurality ,of work loading brackets I are adjustably mounted on the periphery of the pan-shaped member I40 (Figs. 1 and 5). The work loading brackets I4I are each provided with parallel elongated slots I42 and Clamping bolts or screws I44 and I45 pass through the elongated slots I42 and I43, respectively, and are screw threaded into the pan-shaped member I40. By means of this construction, the work loading bracket I may be I adjusted vertically relative to the pan-shaped member and locked in adjusted position by tightening the screws I44 and I45.

The work loading bracket MI is provided with a horizontally movable work transfer member or slide I46 which is provided with a clearance aperture therein shaped and arranged to receive -a work piece I41 to be lapped and to transfer it from a work hopper or magazine I30 into an operativeposition between the lapping wheels I l and I5 (Fig. 1). The slide I46 is preferably moved by means of a hydraulically operated mechanism comprising a cylinder I48 having a slidably mounted piston I49 contained therein. The piston I49 is connected to one end of the slide or transfer member I46 and serves to move the transfer slide I46 toward the right. (Fig. 2)

or ina substantially radial direction (Fig. 3)

relative to the lapping wheels II and I5, respectively. The inner end of the slide I46 is provided with an enlarged trapezoidal-shaped end portion I56 (Fig. 3) having a tapered end portion I5I which mates with a correspondingly shaped aperture I52 formed in a cage member I93.

'The cage member |93 ,is supported by a centrally-located vertically-adjustable rotatable stud I94. The cage member I93, however, is held against rotation by a stop plate I95 which is providedat its inner end with an enlarged shaped end portion which mates with and engages one of the slots ornotches I52 formed in the periphery of the cage member I93. The stop plate I95 is adjustably fastened by a bolt or screw I96 on the upper surface of a supporting bracket I91. The stud I94 may be adjusted vertically to position the cage member I 93 in-the desired position with respect to the operative surfaces of the lapping wheels II and I5. The bracket I91 may be adjusted vertically to adjust the position of the stop plate I95 relative to the cage member I93.

The cage member I93 serves to support and steady the inner end of the slide or work transfer member I46 during a lapping operation. The work transfer slide I46 (Fig. 1) is shown-in a forward or operative position with a work piece I41 in operative position between the lapping wheels II and I5. Each of the work loading brackets I4I, I4Ia, I4Ib, I4Ic, I4Id, I4I.e, I4If, I4Ig, I4Ih, I4Ii and MM is provided with an inclined work discharge chute or passage I55 (Fig. 1) the upper endof which is covered by a slidably mounted member I56. The cover I56 is preferably actuated hydraulically in timed relation with the work transfer slide I46 by means of a cylinder I51 having a piston I56 slidably mounted therein. The piston I58 is connected by means of a piston rod I59 with the slidably mounted cover I56.

When the work transfer slide I46 is moved toward the left (Fig. 1) after a lapping operation has been completed upon the work piece I41, fluid under pressure is admitted to move the cover I56 toward the left (Fig. 2) so that when the work piece I 41 moves into alignment with the upper end of the discharge chute or passage I55, it drops therefrom under the influence of gravity and is discharged into a container I39 which is fastened to the work loader bracket I4I.

Each of the work loading devices is provided with a control valve I66. The control valve I66 is a piston type control valve comprising a valve stem I6I having formed integrally therewith valve pistons I62, I63 and I64. The valve I66 may be actuated manually, if desired, or automachine base. The valve I66 is a piston type valve comprising a valve stem I61 having formed integrally therewith valve pistons I68, I69, I16, Ill and I12. In the position of the valve I66 (Fig. 2), fluid under pressure passing through the pipe I63 enters the valve chamber located between the valve pistons I61 and I68 in the main control valve I64 and passes through a pipe I13, through an adjustable throttle valve I14, and through a chamber located between the valve pistons I68 and I69 in the work loader control valve I66 and passes out through a pipe I15 to convey fluid to an end chamber I 16 in each of the work loader valves I66 to cause the valve stems I6I to move toward the right (Fig. 2) that is, in a radial direction toward the lapping wheels II and I5 (Fig. 3), all of the valves I66 being simultaneously actuated.

During this shifting movement of the valves to push the valve stem I downwardly to admit fluid under pressure to cause a downward approaching movement of the upper lapping wheel I5, fluid under pressure is passed through the pipe I15 to shift all of the valves I66 of the work loading device I6I.

As shown in Fig. 2, fluid under pressure passing through the pipe I 63 also passes through a pipe I86 which enters a valve chamber located between the valve pistons I62 and I63 of the work loader control valves I66, I66a, I 66b, I660, I66d, I66e, I66 I66g, I66h, I662 and I667 and passes 'out through a pipe I8! into cylinder chambers I82 to move the pistons I58, piston rods I59 and cover plates I56 toward the right .(Fig. 2) to cover the discharge chute or passages I55. At the same time, fluid under pressure passing through the pipe I8I passes through adjustable throttle valves I86 into cylinder chambers I83 to move the pistons I49 and work transfer slides I46 toward the right into the position illustrated in Figs. 1 and 2, which movement transfers a work piece I41 from the hopper or magazine I38 toward the right into an operative position (Fig. 1) between the lapping wheels II and I5, respectively. -By adjusting the valves I84, the passage of fluid under pressure into the chambers I83 of the cylinders I48 and N81; to I487 inclusive may be varied as desired so that the pistons I58 actuating the cover plates I56 are moved to cover the discharge chutes I55 before the work transfer slides I46 move the work piece I41 across the aperture at the upper end of the discharge chutes I55.

, During the movement of the pistons I49 and I58 toward the right (Fig. 2), fluid is exhausted from cylinder chambers I85 in the cylinders I51 through pipes I86 and is also exhausted from cylinder chambers I81 in the cylinders I 48 through pipes I88 into common exhaust pipes I89 which pass exhaust fluid through'a valve chamber located between the valve pistons I 63 and I64 in i the control valve I66 and pass the exhaust fluid through a pipe I96 into the exhaust pipe II1 which exhausts the fluid into the reservoir I66.

Each of the plurality of work loading devices the right and left-hand end chambers of the HI and the hydraulic mechanisms for actuating the same are identical in construction, consequently only one of these mechanisms has been described in detail. All of the hydraulic control mechanism, however, is diagrammatically illustrated (Fig. 2) and corresponding parts are designated by the corresponding numerals suflixed with the letters a, 'b, 0, d, e, f, g, h, i, and 7'. It will be readily apparent from the foregoing disclosure that when fluid is admitted through the pipe I15, it will simultaneously be admitted into the end chambers I16, I160, I16b, I160, I'I6d, I160, I16 I16g, I16h, I16i and I16 to shift the valves I60, I60a, I601), I600, I60d, I60e, I60j, I60 I60h, I601 and I607 toward the right into the positions indicated in Fig. 2. In this position of the valves, fluid under pressure passing through the pipe I80 is admitted to the left-hand end chambers of the cylinders I48 and I51, respectively, of each of the work loading devices simultaneously to'shift the cover plates I56 toward the right to cover the discharge chutes I55 and at the same time move the work transfer slides. I46, I460, I46b, I460, I46d, I46e, I46 I46g, I46h, M612 and I46j toward the right (Fig. 2) that is, in a radial direction (Fig. 3) to transfer new work pieces I41 from the hoppers I38 into an operative position between the lapping wheels II and I5.

Similarly, when the main control valve I04 is shifted upwardly under the influence of the spring I34 when the solenoid I36 is deenergized,

the direction of flow of fluid under pressure is This movement of the valves I60 serves to admit fluid under pressure'through the pipes I89, I89a, I891), I890, I89d, I89e, I89 I89g, I89h, I89i and I897 to move the work transfer slides I46 toward the left (Fig. 2) that is, in a radial direction (Fig. 3) to remove the work pieces from an operative position between the lapping wheels II and I5, respectively. At the same time, fluid under pressure is simultaneously admitted to the cylinders I51 to move the cover plates I56 toward the left to uncover the discharge chutes I55. Due to the adjustment of the throttle valves I04, the

speed of movement of the work transfer slide I46 may be adjusted as desired so that the cover plates I56 will move more rapidly to uncover the discharge chutes I55 before the lapped work pieces I41 move into alignment with the discharge chutes I 55. When the work transfer slides I46 move the work pieces I41 into alignment with the discharge chute I55, the work piece drops into the discharge chutes I55 and slides into the containers I39. The work transfer slides I46 continue their movement toward the left (Fig. 2), that is, in an outward radial direction (Fig. 3) until the work receiving aperture in the work transfer slides I46 is aligned with the column of work pieces I41 positioned in the work hopper or magazines I38. A new work piece v I41 then drops into operative position in the work receiving aperture of the work transfer slide I46 ready for the next loading operation.

In case it is desired to operate the work loading devices I4I. manually and individually, the work loader control valve I66 may. be shifted toward the left (Fig. 2), which movement opens both work loader valves I60, I600, I601), I600, I60d, I600, I60 I609, I60h, I601 and I60i to the exhaust pipe line so that all of these control valves maybe manually and independently actuated to control the work transfer slides I46 governed devices and the pressure control for the lapping operation may be automatically controlled to produce a predetermined lapping operation. The main control valve I04 is normally held in its uppermost position by means of a tension spring I34. An electrical control apparatus is provided comprising a push button 200 (Fig. 2)' which serves to start the lapping cycle. When the push button 200. is closed, it closes a circuit setting in motion an adjustable electrical time relay 20I which may be any of the standard well-known relays; such as that known as the Microflex man-. ufactured by Eagle Signal Corporation of Mollne, Illinois. relay 20I, the solenoid I36 is energized to push the valve stem I05 downwardly into the position shown in Fig. 2. The time relay 20I serves to control the overall lapping cycle and the solenoid I36 remains energized until the time relay 20I operates again to deenergize it at the end of a predetermined lapping cycle.

A similar Microflex electrical time relay 202 is provided. This relay is operatively connected to be set in motion when the push button 200 is closed and the relay 20I is started. When the time relay 202 is set'in motion, it energizes the solenoid I26 to shift the valve I25 into the position illustrated in Fig. 2, so that the lapping operation proceeds initially at a relatively high pressure as controlled by the pressure relief valve I I8. After a predetermined time interval during which the work pieces are lapped while the lappihg wheel I5 is held in contact therewith by a pressure as controlled by relief valve 8, the time relay 202 operates to deenergize the solenoid I26 so that the released compression of the spring within the valve I25 moves it toward the right (Fig. 2), thus allowing fluid under pressure to pass through the pipe I24, manually operable valve I23 and pipe I22 through the relief valve I2I which may be set for a lower pressure than valve II8 which governs the lapping pressure for the remainder of the lapping cycle.

When the cycle of operation is started by the closing of the push button switch 200, a relay 203 is energized to break a circuit so as to render a Microflex electric time relay 204 inoperative. After the lapping operation has continued for a predetermined time interval as governed by the 'time relay 20I, a circuit isbroken, thus deenergizing the solenoid I36 so as to release'the tension of the spring I34 which returns the valve I04 to its uppermost-position, thus raising the upper lapping wheel assembly and at the same The time relays 20I, 202 and 204 are all ofthe adjustable automatic reset type, such as the Microflex, or any of the other standardwell known types.

When the electric time relay 20| trips at the Simultaneously with the starting of the end of .the' lapping cycle, the relay 203 is deenergized which serves to make a circuit and thereby set the time relay 204 in operation. The adjustable time relay 204 is set for a predetermined time interval suflicient to allow the work loading devices to operate, namely to unload the lapped pieces of work and to pick up a fresh piece of work from the work hoppers or magazines I38 and to move them into an operative position. When the time relay 204 trips, it serves again to set in motion the time relays 20I and 203 automatically. to start the next lapping cycle. By adjusting th time relay 204, the time interval required for unloading and loading of work pieces may be readily adjusted as desired. It will be readily apparent from the foregoing disclosure that by 'closing the push button switch 200, the lapping cycle may be started to lap firstone batch of work pieces I41 which are then automatically ejected and a fresh batch of work pieces I" are automatically presented and the next cycle automaticallycontinues. This automatic continuous cycle continuesto function until the machine is stopped by the operator.

When it is desired to stop the lapping cycle, the operator. pushes a push button 205 which to returnthe parts to their inoperative positions. A manually operable switch 206 is provided whereby the relay 202 may be rendered inoperative so that by closing the manually operable valve I23, the entire lapping cycle may be carried on at one pressure as governed by the throttle valve H8 or, if the manually operable valve I23 remains open, then the entire lapping pres-'- sure during the cycle of operation will be governed'by the pressurerelief valve I2 I'.

A manually operable switch 201 is provided for rendering the time relay 204 inoperative, thus making a semi-automatic cycle which is con- .trolled by the push button 200. If the semi-auton rendering the entire automatic cycle inoperative,

thus cutting out

relays

20I, 202 and 204. When the switch 208 is opened, the machine may be manually controlled by means of the manually operable control lever I30 which controls the shifting of the main control valve I04.' A normally open switch 209 is provided so that when the switch 208 is opened, the-switch 209 may be may be provided to hold the upper lapping wheel serves immediately to stop the lapping cycle and .exhaust from the pipes I09 and H6 and fluid under pressure may by-pass through a pipe 2 which connects between the pipe lin I03 and the valve I I0 with the pipe I09 so that a pressure I5 in a downward direction with the stop screw 82 inrigid engagement with the stop 80 during the lapping operation. In this position of the parts, the actuation of the main control valve I04 operates to control the actuation of the work loading devices only as governed by the electric time relay 20I so that work pieces are intermittently and automatically fed in a substantial axial direction into a fixed grinding throat bewheel I5. Assuming the electrical control apparatusis set for an automatic continuous cycle of operation, the cycle of lapping may be started by manually closing the push button switch 200 which, as above described, sets the electric time relays 20I and 202 in operation and at the same time energizes the solenoid 136 to shift the valve I04 in a downward direction so as to admit fluid under pressure to cause the upper lapping wheel I5 to move downwardly into an operative position and at thesame time admit fluid under pressure to the work loading devices to shift the work transfer slides so as to present a plurality of work pieces I41 simultaneously into an operative closed to energize the solenoid I36 manually when desired to start and stop a manually controlled cycle, thus obviating the necessity of actuation of the control lever I30.

If desired, the upper lapping wheel I5 may be moved downwardly into a fixed position with the stop screw 82 in engagement with the stop 80, thus positioning the lappinz'wheel I5 relative to the lapping wheel II. The lapping wheels II and I5 may be maintained in this position while the workpieces I41 are fed in an axial or radial direction into the throat between the two lapping wheels and the'desired lapp action may be obtained by this axial feeding component. If the machine is operated in this manner, the speed of movement of the work pieces, that is,

. the speed of movement of the'work transfer position between the lapping wheels II and I5.

The lapping operation continues for a predetermined time interval as determined by the setting of the time relay20l. After the lapping operation has proceeded for the definite time interval, the tripping of the relay 20I deenergizes the solenoid I36 to allow the released tension of the spring I34 to return the valve I04 in an upward direction to again raise the'upper lap-.

ping wheel I5 and to admit fluid under pressure to the work loading devices to remove the lapped work pieces from an operative position and to 8 allow them to be ejected or discharged throughthe passages I55. If during this operation the switch 206 is closed, thus rendering the electric time relay 202 operative, this relay is set in motion simultaneously with the relay 20I and serves to control the valve I25 so that for an initial predetermined period, the upper lapping wheel I5 will engage the work'at one pressure the lapping cycle, the tripping of the relay 2M position between the lapping wheels II and l5.

It will thus be seen that there has been prov vided by this invention apparatus in which the various objects hereinabove set forth together with many thoroughly practical advantages are successfully achieved. As many possible embodiments may be made of the above. invention and as many changes might be made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

We claim:

1. In a lapping machine having a base, a pair of opposed relatively rotatable lapping wheels, means relatively to rotate said wheels, means to cause a relative approaching and receding movement between said lapping wheels, an ad- Justable stop to limit the approaching movement of. said wheels, and a plurality of work loading devices, each comprising a work magazine, a reciprocable work transfer slide to convey work pieces from the magazine into an operative position for a lapping operation and to convey work pieces therefrom after a lapping operation.

-2. In a lapping machine having a base, a pair of opposed, relatively rotatable lapping wheels, means relatively to rotate said wheels, means to revolve at least one of said wheels in an orbital path, means to cause a relative approaching and receding movement between said lapping wheels, a work steadying cage having a plurality of slots formed in its periphery, an adjustable stop to limit theapproaching movement of saidwheels, and a plurality of work loading devices one opposite each of the slots in said cage, each comprising a magazine or hopper, a reciprocable work transfer slide to convey work pieces from the hopper into an operative position, a shaped end on said slide to mate with a slot in said cage whereby the cage serves to steady the slide, and work piece, and a fluid pressure mechanism including a piston and cylinder operatively connected to actuate said slide.

3. In a lapping machine having a base, a pair of opposed, relatively rotatable lapping wheels, means relatively to rotate said wheels, means including a piston and cylinder to cause a relative approaching and receding movement between said lapping wheels, an adjustable stop to limit said approaching movement, a plurality of work loading devices arranged about the periphery of said wheels, each comprising a work magazine or hopper, a reciprocable work transfer slide to convey work pieces from the hopper to an operative position between said lapping wheels, means including a piston and cylinder operatively connected to actuate said slide, and a main control valve simultaneously to control the admission offluid to the lap approaching cylinders and to all of said work loader cylinders.

4. In a lapping machine having a base, a pair of opposed relatively rotatable lapping wheels having plane operative faces, means relatively to rotate said wheels, means including a piston and cylinder to cause a relative approaching movementbetween said wheels, means to limit, said approaching movement to provide a predetermined lapping throat, and a plurality of work loading devices arranged about the periphery of said wheels, each comprising a work magazine or hopper, and a work transfer member intermittently to convey work pieces from said hopper in the lapping throat.

5. In a lapping machine having a base, a pair of opposed relatively rotatable lapping wheels having plane operative faces, means relatively to rotate said wheels, means including a piston and cylinder to cause a relative approaching movement between said wheels, means to limit said approaching movement to provide a predetermined lapping throat, and a'plurality of work loading devices arranged about the peripheryof said wheels, each comprising a work magazine or hopper, a work transfer member on each of said devices, and automatically operated mechanism to move said member automatically to feed work pieces from said hopper into the lapping throat to lap the work to a predetermined extent.

6. In a lapping machine having a base, a pair of opposed relatively rotatable lapping wheels,

- means relatively to rotate said wheels, means including a piston and cylinder to cause a 'relative approaching and receding movement between said wheels, a work loading device, means including a piston and cylinder on said work loading device operatively connected to present work pieces intermittently into operative relation with the grinding wheels, a reversing valve for said latter cylinder, said reversing valve having end chambers whereby it is automatically shifted by fluid under pressure, and a main control valve simultaneously to admit fluid under pressure to cause an approaching movement of said lapping wheel and. to admit fluid under pressure r0 one of the end chambers to shift said reversing valve and to control the admission of fluid under pressure to the work loader cylinder automatically to transfer a work piece into operative position between said lapping wheels as the lapping wheels approach each other to produce a predetermined lapping operation.

7. Ina lapping machine having a base, a pair of opposed relatively rotatable lapping wheels, means relatively to rotate said wheels, means to cause a relative approaching and receding movement between said lapping wheels, a non-rotatable work steadying cage having a plurality of shapednotches in its periphery, and a plurality of work loading devices spaced around the periphery of said lapping wheels each of which includes a work hopper, a reciprocable transversely movable work transfer slide, the inner end of said slide being shaped to engage a notch in said cage when the slide is in an operative position, and means to reciprocate the work transfer slide automatically and intermittently to transfer a work piece from said hopper into an operative position.

8. In a lapping machine having a base, apair of opposed relatively rotatable lapping wheels,

' means relatively to rotate said wheels, means includes a work hopper, a reciprocable transversely movable work transfer slide,the inner end of said slide being shaped to engage a notch in said cage when the slide is in an operative 9. In a lapping machine having a base, a pair of opposed relatively rotatable lapping wheels, means relatively to rotate saidwheels, means to cause a relative approaching and receding movement between said lapping wheels, a nonrotatable work steadying cage having a plurality of shaped notches in its periphery, and a plurality of work loading devices spaced around the periphery of said lapping wheels each of which includes a work hopper, a reciprocable transversely movable work, transfer slide, the inner end of said slide being shaped to engage a notch in said cage when the slide is in an operative position, and means including a piston and cylinder on each of said loading devices to reciprocate the work transfer slide automatically and intermittently to transfer work pieces from said hopper into an operative position.

.10. In a. lapping machine having a base, a pair of opposed relatively rotatable lapping wheels, means relatively to rotate said wheels, means to cause a relative approaching and receding movement between said lapping wheels, a non-rotatable work steadying cage having a plurality of shaped notches in its periphery, and

a plurality of work loading devices spaced around the periphery of said lapping wheels each of which includes a work hopper, a reciprocable transversely movable work transfer slide including a clearance aperture therein shaped to receive a work piece, and means including a piston and cylinder on each of said loading devices to reciprocate the work transfer slide intermittently to transfer work pieces into and away from an operative position between said lapping wheels.

11. In a lapping machine having a base, a pair of opposed relatively rotatable lapping wheels, means relatively to rotate said wheels, means to ceding movement :between said lapping wheels, a non-rotatable work steadying cage having a plurality of shaped notches in its periphery, and a plurality of work loading devices spaced around the' periphery of said lapping wheels each of which includes a work hopper, a reciprocable transversely movable work transfer slide having a clearance aperture therein shaped to receive cause a relative approaching and receding movement between said lapping wheels, a nonrotatable work steadying cage having a plurality of shaped notches in its periphery, and -a plurality of work loading devices spaced around the peri-' phery of said lapping wheels each of which includes a work hopper, a reciprocable work transfer slide having a clearance aperture shaped to receive a work piece, means including a piston and cylinder on each of said loading devices to reciprocate the slide intermittently to transfer work pieces into and away from an operative position between said wheels, and a fluid pressure system including a main control valve operatively connected simultaneously to control the admission to and exhaust of fluid from all of said loading device cylinders.

12. In a lapping machine having a base, a pair of opposed relatively rotatable lapping wheels, means relatively to rotate said wheels,

means to cause a relative approaching and rea work piece, the inner end of each of said slides being shaped to engage one of the notches in said cage when the slides are in an operative position, and means including a control valve simultaneously to control the admission to and exhaust of fluid from all of the work loading cylinders.

13. In a lapping machine having a base, a pair of opposed relatively rotatable lapping wheels means relatively to rotate said wheels, means to cause a relative approaching and receding movement between said lapping wheels, a non-rotatable work ste'adying cage having a plurality of shaped notches in its periphery, and i a plurality of work loading devices spaced around the periphery of said lapping wheels each of which includes a work hopper, a reciprocable work transfer slide having a clearance aperture therein shaped to receive a work piece, a work discharge chute, a slide adjacent to and below said work transfer slide normally to cover said discharge chute, a piston and cylinder operatively connected to move said work transfer slide intermittently to transfer work pieces from said hopper into an operative position between said wheels, a second piston and cylinder operatively connected to move said work supporting slide on the withdrawal stroke of the work piece to allow the work piece to drop into the discharge chute.

14. In, a lapping machine having a base, a pair of opposed relatively rotatable lapping wheels, means relatively to rotate said wheels, means to cause a relative approaching and receding movement between said lapping wheels, a non-rotatable work steadying cage having a plurality of shaped notches in its periphery, and a plurality of work loading devices spaced around the periphery of said lapping wheels each of whichincludes a work hopper, a reciprocable work transfer slide having a clearance aperture therein shaped to receive a work piece, means including -a piston and cylinder to reciprocate said slide intermittently to transfer work pieces from said hopper into an operative position between the lapping wheels, a work discharge passage, a. slide normally covering said passage, and an independent piston and cylinder mechanism to move said work supporting slide, and a fluid pressure control system including a valve for controlling the rate of movement of the transfer slide so that the movement of the transfer slide may be retarded so-that the work supporting slide moves ahead of the transfer slide to insure support' of the work piece during its in movement and to withdraw the support on the return stroke after a. lapping operation to allow the work piece to dropinto the discharge passage.

. HIEERBERT S. INDGE.

' FRANKLIN E. JOHNSON.