US2141491A

US2141491A - Lapping device

Info

Publication number: US2141491A
Application number: US157648A
Authority: US
Inventors: Raymond R Searles
Original assignee: Fafnir Bearing Co
Current assignee: Fafnir Bearing Co
Priority date: 1937-08-06
Filing date: 1937-08-06
Publication date: 1938-12-27
Anticipated expiration: 1955-12-27

Description

R. R. SEARLES LAPPING DEVICE Dec. 27, 1938.

Filed Aug. e, 1957 llfirlh lNvENToR RAYA/MND 1Q. 554/?55 TToRNEYs.

Patented Dec. 27, 1938 My invention r device, but which honing, polishing,

' LArrlNG DEVICE Raymond R. Searles,

or to The Fafnir Bearing Company,

a corporation of Connecticut' ain, Conn.,

New Britain, Conn., assign- New Brit- Application August s, 1937, semi No. 157,648

2 Claims.

elates to what I term a lapping may be adaptedV for grinding, etc., all of which operations I wish to include within the term lapping It is the principal object of my invention to provide an improved lapping device, particularly though not exclusively adapted for lapping the raceway grooves for ball It is a further object lapping device which may be very readily actuated.

bearings. to provide an improved A further object is to provide an improved may be veryreadily and Another object come apparent to those lapping device so arranged and operated that it quickly brought into and out of lappingl position.

is to provide an improved lapping device in which the lapping pressure may be quite readily predetermined and maintained.

Other objects and various features of invention will be hereinafter pointed out or will beskilled in the art.

In the drawing which shows, for illustrative purposes only,

preferred forms of the inventionin partial section of a Fig.2 is a fragmentary view, similar to Fig. 1,

and illustrating a slightly modied form of the invention.

In the particular embodiment of the invention herein illustrated for lapping the raceway grooves of ball bearings, I employ what may be termed a lapping head 5 carried by and bodily rotatable with a spindle 6 rotatably mountedin ball bearuch as 1 carried by a frame 8. The lapping -ings s head 5 carries mova ble lapping tools 9 9, which in the form illustrated are pivotally mounted as at I to the lapping head so that the laps proper I I-I I may be moved into and out of engagement with the work which, as illustrated, is an outer ring I2 of a ball bearing. The ring I2 is carried in a suitable pocket chuck I3 on a rotatable spindle IB. The lapping tools are movable pref` erably by iiuid pressure least one direction. As

actuated means in at illustrated, the spindle 6 is hollow and carries an actuator or draw rod I5. Adjustably mounted on the front end of the draw rod I is a toggle head I6 and toggle links I'I-I1 are pivotally connected to the toggle head and the lapping tools 9-9 so that when the actuator I5 and toggle head I6 are moved toward the right the laps ment with the wor head IB and actuator left, the laps II-II will II-II will be urged into engagek and, conversely, when the I5 are moved toward the be moved substantially or passage members radially away from the work so as to permit the chuck to be Withdrawn and a new work piece substituted.

The actuator I5 in the preferred form is operated by huid pressure actuated means, which 5 may include a piston I8 carried by the rear end of the actuator rod I5 and mounted in a cylinder I9, as will be understood. Fluid pressure passages -2I communicate with the cylinder at opposite ends of the piston I8 and uid pres- 10 sure passage members or pipes 22-23 communicate respectively with the passages 20--2I and. serve to conduct pressure iluid to and from the ends of the cylinder, as will be clear. The pipes 22-23 may be connected '5 to an ordinary three-wayvalve, entirely familiar to those skilled in the art, whereby iluid may be directed at will to the cylinder at one side of the piston I8 and exhausted from the other side so as to actuate the actuator rod I5 and thus rock 20 the toggle for actuating thelappingtools 9 9.

In that form of the invention shown in Fig. 2, the parts may be substantially the same as those shown in Fig. 1. However, the lapping tools 9'9' are provided with bulges or other means to 25 providegreater weight, since Ain the form shown in Fig. 2 the tools 99' are adapted to be thrown outwardly centrifugally` so as to bring the laps II-II into engagement with the work. The toggle head It may be the same as heretofore described and preferably the links IIL-I1' are connected to tools 9'Q' by a pin and slot connection indicated generally at 2i. In that form shown in Fig. 2, the work head spindle H is mounted on one axis, the center line being shown in dot-dash lines, while the spindle d is mounted upon another axis out of alignment with the axis of the work spindle IB. Therefore,

the laps II--II being generally .concentrically and symmetrically arranged relatively tothe axis 4o IIL-the laps will engage the raceway bearing constituting the work piece at opposite sides of the groove when the lapping tools are arranged oppositely, all as will be clear from Fig. 2. Duringrotation of the lapping head and the work -head at diierent speeds, the laps will traverse the raceway groove in generally spiral fashion so. as to lap the entire surface. With the work head and thelapping head mounted on the same axis, as may be considered the condition in Fig. 1, the laps II--II will simply track around within the raceway groove and may be considered as form laps, whereas the laps II-II of Fig. 2 need not be form laps since the shape of the lap is not relied of the spindle groove of the ball upon for lapping the surface, owing to the fact that the laps traverse the entire surface of the 81'O0Ve.

In the form shown in Fig. 2, as stated the laps are designed to be thrown out into lapping operation and yet permit the laps to be fully retracted bythe toggle mechanism. The laps of Fig. 1 as indicated are designed to be moved both into and out of engagement by means of the toggle lever mechanism shown. By providing a yielding connection betwen the lapping tools S- and the toggle head I6, the axes of the spindles I4 and 6 could be oiset so as to cause the laps lI--H to traverse the entire groove after the manner of Fig. 2.

By means of the toggle actuation of the lapping tools very slight force is required to move the lapping tools and the latter may be retracted to permit the insertion of a new work piece, all Without stopping the rotation of the spindle 6. The fluid pressure actuated means which in the form shown in Fig, l'serves to urge the laps into lapping engagement with the work is highly advantageous in that there is a substantially constant and uniform pressure urging the 'laps into engagement with the work and that pressure Y tends to follow up so as to cause a substantially constant pressure on the laps even though they may Wear to some extent. By properly proportioning and adjusting the toggle mechanism as well as the uid pressure in Fig. 1, the lapping pressure may be very accurately predetermined and maintained. By properly designing the lapping tools 9-9' of Fig, 2 and rotating the spindle at the proper speed, the lapping pressure may also be accurately predetermined.

A lapping device built in accordance with my invention is rapid in production in that the lapping tools may be rotated constantly and the work head withdrawn and new work pieces substituted, all without stopping the rotation of the lapping tools and when the work head rotates at a sufficiently slow speed, without stopping its rotation. It may be said that, generally speaking, the lapping tools are rotated at a rapid rate while the work piece is rotated quite slowly.

It Will be'clear to those skilled in the art that the device may be arranged for lapping the raceway grooves of inner rings of ball bearings.

While the invention has been described in considerable detail and two forms illustrated, it is to be understood that the invention may be variously embodied for lapping various articles and surfaces and that changes and modiications may be made within the scope of the invention as dened in the appended claims.

I claim:

1. In a device of the 'character indicated, a support, Ia spindle rotatably mounted thereon, a cylinder xedly mounted on one end of said spindle, a lapping head xedly mounted on the other end of said spindle, lapping members carried by said head, actuating members for said lapping members, a piston in said cylinder, a piston rod passing axially through said spindle and connected to said piston and said actuating members, means for subjecting said piston to uid pressure for actuating said lapping members, and means for rotating said spindle, cylinder and lapping head as a unit.

2. In .a device of the character indicated, a support, a spindle rotatably mounted thereon, a

lapping head carried by said spindle, lapping' members carried by said head, toggle mechanism for actuating said lapping members in at least one direction, a toggle actuator connected to said toggle mechanism and passing axially through said spindle, and fluid pressure actuated means for moving said toggle actuator for the purpose described.

RAYMQND R. sEARLEs.