US3677052A

US3677052A - Ring gear rounder

Info

Publication number: US3677052A
Application number: US33795A
Authority: US
Inventors: Russell W Anthony; Carl H Motz
Original assignee: Lear Siegler Inc
Current assignee: Nachi Machining Technology Co
Priority date: 1970-05-01
Filing date: 1970-05-01
Publication date: 1972-07-18
Anticipated expiration: 1989-07-18

Abstract

A combined ring gear rounder and gear tooth burnisher in which the gear is driven in rotation by a drive pinion, a burnishing pinion engages the gear teeth diametrically opposite to the drive pinion, means are provided for moving the burnishing pinion toward and away from the drive pinion to provide for loading and to provide burnishing pressure between the teeth of the burnishing pinion and ring gear. Rollers engaging the smooth side of the ring gear at opposite sides thereof at zones intermediate the drive and burnishing pinions are movable radially inwardly and outwardly with respect to the ring gear to effect ring rounding.

Description

United States Patent Anthony et al.

[54] RING GEAR ROUNDER [72] Inventors: Russell W. Anthony; Carl H. Motz, both of Harper Woods, Mich.

s2 U.S.Cl ..72/107,72/10s,29/1s9.2 s1 1m.c1 ..B2lh5/00 [58] FieldofSearch ..72/l05,l06,l07, 108,110,

[56] References Cited UNITED STATES PATENTS 3,353,392 11/1967 Anthony et al. ..72/11o 1451 July 18, 1972 3,000,426 9/ l 961 Ducker et al. ..72/1 10 3,505,847 4/1970 Anthony et al. ..72/1 10 Primary Examiner-Lowell A. Larson Attorney-Whittemore, Hulbert & Belknap [57] ABSTRACT A combined ring gear rounder and gear tooth burnisher in which the gear is driven in rotation by a drive pinion, a bumishing pinion engages the gear teeth diametrically opposite to the drive pinion, means are provided for moving the bumishing pinion toward and away from the drive pinion to provide for loading and to provide bumishing pressure between the teeth of the bumishing pinion and ring gear. Rollers engaging the smooth side of the ring gear at opposite sides thereof at zones intermediate the drive and bumishing pinions are movable radially inwardly and outwardly with respect to the ring gear to efiect ring rounding.

11 Claims, 6 Drawing figures PATENTED JUL 1 8 I872 SHEET 1 [1F 2 l WL 1 ,INVENTORS RUSSELL w. ANTHONY M/ AR H. MOTZ I W r M! 7 ATToRNE1 s ms ms mm; GEAR ROUNDER CROSS-REFERENCE TO RELATED APPLICATION The application is a Continuation-in-Part of our prior application Ser. No. 728,718 now abandoned, filed May 13, 1968, and also relates to subject matter similar to that disclosed in our prior U.S. Pat. No. 3,505,847.

BRIEF SUMMARY OF THE INVENTION In the present case the invention comprises apparatus including a frame on which is mounted a drive pinion. The drive pinion is preferably located in a fixed position with its axis horizontal and means are provided for driving the pinion in rotation. Carried by the frame is a burnishing pinion, and means are provided for moving the burnishing pinion toward and away from the drive pinion to provide for loading a ring gear with its teeth in mesh with both of the pinions and for applying predetermined burnishing pressure between the teeth of the ring gear and pinions.

Ring rounding pressure is applied at diametrically opposite points to the smooth circular exterior surface of the ring gear and, in the case of an internally toothed ring gear, this pressure is applied by rollers which are movable toward and away from each other and which accordingly apply only substantially radially inwardly directed forces to the ring gear.

With this arrangement the burnishing pressure may be selected and maintained independently of the ring rounding pressure and the application of the relatively great ring rounding pressure is applied through opposed rollers so that these forces are essentially balanced and are not applied to pinions or other additional ring supporting means as has been the practice in the past.

The invention is applicable both to internally and externally toothed ring gears in which the surface of the ring gear opposite the toothed surface is a smooth cylindrical surface.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevational view, partly in section, of the apparatus.

FIG. 2 is an elevational view of the apparatus as viewed from the right of FIG. 1.

FIG. 3 is an enlarged sectional view on the line 33, FIG. 2.

FIG. 4 is an enlarged sectional view on the line 4-4, FIG. 2.

FIG. 5 is a diagrammatic view showing the preferred relationship between the ring gear, the drive and burnishing pinions, and the pressure rolls.

FIG. 6 is a view similar to FIG. 5 showing the application of the invention to an externally toothed ring gear.

DETAILED DESCRIPTION While the invention is readily applicable to both internally and externally toothed ring gears, the detailed description of a preferred embodiment of the invention will be of an internally toothed ring gear.

The apparatus for performing the simultaneous burnishing and rounding of ring gears comprises a frame indicated generally at 10 having a drive shaft 12, which as best seen in FIG. 3 has keyed to one end thereof a sheave 14 adapted to be driven by a belt 16. The shaft 12 is mounted in a fixed position in the frame 10 as by the bearings indicated at 18 and 20, and it will be observed that in the present embodiment of the invention the shaft 12 is horizontal.

At the end of the shaft 12 opposite to the sheave 14 is a reduced shaft portion 22 adapted to carry a drive pinion 24. The end of the shaft 12 beyond the drive pinion 24 is given an outboard support as indicated at 26 by means of a laterally extending support bracket 28 suitably affixed to the frame 10.

In use the drive pinion 24 is in mesh with the teeth at the interior of a ring gear G, as best seen in FIG. 5. In order to burnish the teeth of the ring gear there is provided a burnishing pinion 30 which is adapted to mesh with the teeth of the ring gear G at the upper side thereof. The burnishing pinion 30 is rotatably mounted on a shafi 32 which is carried by a bracket 34 substantially enclosing the burnishing pinion in a cavity as indicated at 36 but leaving its upper side exposed for meshing engagement with the teeth of the ring gear G. The bracket 34 is keyed to a shaft 38 rotatably mounted in an opening 40 provided in the frame 10. A lever arm 42 surrounds an intermediate portion of the shaft 38 and is keyed thereto as indicated at 44. The lever 42 is coupled by pin 46 to a clevis 48 connected to the lower end of a piston rod 50 which is connected to a piston vertically movable within a fluid pressure cylinder 52.

With the structure as so far described a work gear may be positioned as shown in FIG. 5 to be in mesh with the drive pinion 24 and the burnishing pinion 30. This may be done manually but preferably, automatic loading mechanism is provided which positions the ring gear over the

pinions

24 and 30 while the burnishing pinion 30 is in its lowered position. Thereafter, pressure is admitted to the cylinder 52 to swing the lever 42 clockwise and thus to raise the burnishing pinion into tight mesh with the teeth of the ring gear and to apply burnishing pressure thereto. Upon completion of the operation the burnishing pinion 30 is lowered and the burnished and rounded ring gear G may then be removed.

In addition to the burnishing operation as so far described, the apparatus is provided with mechanism for applying ring deforming pressure to the ring gear as it is driven in rotation so as to effect a rounding of the gear. This operation is more fully described in our prior U.S. Pat. No. 3,353,392 referred to above.

The mechanism for accomplishing this purpose comprises a pair of arms 60 each of which is mounted for rotation on a relatively heavy shaft 62, the arms 60 at the lower ends thereof carrying pressure rolls 64 which are mounted for rotation by shafts 66. At their upper ends the arms are interconnected by a tension spring 67 urging the rolls 64 outwardly away from the ring gear G. In order to apply ring deforming radially directed pressure, the arms 60 adjacent their upper ends are provided with cam follower rollers 68 engageable with a rotary cam 70, the cam being keyed to a shaft 72 which extends into a motor housing 74. The motor is preferably a vane type fluid motor capable of effecting only limited rotation of its output shaft 72. Moreover, the rate at which the rolls 64 are moved inwardly and outwardly may be readily controlled with this type of motor which includes means for metering the flow of the actuated fluid.

With the parts in the position illustrated in FIG. 2, it may be assumed that the rolls 64 have been moved inwardly into contact with the round outer surface of the ring gear G, this inward movement having been caused by coaction between the cam followers 68 and the flat portions 76 of the cam. The curved portions 78 of the cam provide a gradual rise so that the force applied by continued rotation of the cam 70 may be relatively great and of ring deforming intensity.

Connecting the upper ends of the arms 60 is a link 80 one end of which is pivoted to one of the arms as indicated at 82. Adjacent its other end, the link 80 is slotted as indicated at 84 and movable longitudinally in the slot is an abutment pin 86 fixed to the upper end of the arm 60. An adjustable abutment screw 88 is provided at the end of the link and extends into the elongated slot 84. Separation between the upper ends of the arms 60 by the action of the cam 70 is thus limited by engagement between the pin 86 and the inner end of the abutment screw 88. This adjustment of course is made for a particular sequence of gears to be rounded.

In operation the gear is brought into position so as to be suspended from the burnishing pinion 30, at which time the pinion 30 is elevated to apply burnishing pressure between the teeth of the burnishing pinion and the internal teeth of the ring gear. The pinion 24 drives the ring gear G in rotation and substantially radially inward pressure is applied to the ring gear by the pressure rolls 64. The rate of application of pressure and hence of deformation of the ring gear, is correlated to the rotation thereof and the pressure is reduced at a controlled rate by controlled movement of the cam 70 so that any ovality or outeof-round existing in the ring gear as a result of its manufacture, particularly including heat treatment thereof, is effectively eliminated.

Referring now to FIG. 6, the application of the invention to performing a rounding operation and burnishing the teeth of an externally toothed ring gear is illustrated. in this Figure the ring gear is indicated at 90, the ring gear having external teeth 91 and having a smooth cylindrical interior surface 92. The apparatus comprises the

pinions

93 and 94 one or both of which is positively driven in rotation and these pinions, like the

pinions

24 and 30, are biased radially of the ring gear so as to establish a predetermined burnishing pressure between the teeth of the pinions and gear. This means for establishing the burnishing pressure may of course be a pressure piston and cylinder device such as described in conjunction with the mechanism for operating on internally toothed gears.

Located within the gear 90 are a pair of smooth surfaced

rolls

95 and 96 which are adapted to be urged apart with considerable force so as to distort the ring gear 90 in an operation equivalent to the distorting of the ring gear G by the rolls 64. Obviously, the

rolls

95 and 96 may be mounted on lever arms corresponding to the arms 60 and biased by suitable means such as a rotatable cam equivalent to the cam 76 so as to apply the distorting pressure. Obviously of course, since the

rolls

95 and 96 are moved away from each other during the application of distorting pressure, the location of a cam biasing the roll supporting arms will have to accommodate this motion. This obviously may be accomplished by having the arms in effect cross each other and be mounted on a common pivot axis.

An important advantage of the present construction over anything heretofore available in the prior art is the capability of controlling the pressure applied between the burnishing pinion 34 and the teeth of the ring gear G, irrespective of whatever forces are required to be applied through the pressure rolls 64 to produce the required deformation of the ring gear. It has been found that where pressure of ring gear deforming intensity is applied by a pair of pinions meshing internally with the ring gear, the pressures developed may be so great as to damage the teeth of the gear particularly by causing lateral deflection thereof. On the other hand, where a pair of externally acting rolls at fixed center distance are moving generally tangentially over the round outer surface of a ring gear to the centralized position thereof, the operation results in substantial lateral forces applied to the ring gear. In the present case the pressure rolls are moved substantially directly radially inwardly with respect to the ring gear and hence, the thrusts of the two pressure rolls are balanced. Therefore, while these pressure rolls cause some flattening or deformation of the ring gear they cause no appreciable pressure effect on the teeth of the ring gear and the pinions in mesh therewith. Accordingly, it is possible to produce pressures of relatively great magnitude as required for correcting ovality of the ring gear while maintaining only sufficient burnishing pressure to perform the required burnishing operation on the teeth of the ring gear.

While the two pinions which mesh simultaneously with the teeth of the ring gear are referred to as a drive pinion and a burnishing pinion, it will of course be apparent that either pinion may be positively driven to operate as the drive pinion, or in a proper case, both pinions may be positively driven. Similarly, it will of course be recognized that since the pinions are relatively radially movable into tight mesh with the teeth of the gear, that both pinions in fact perform a burnishing action.

What we claim as our invention is:

1. Apparatus for simultaneously rounding a ring gear and burnishing its teeth, in which the ring gear may by internally or externally toothed and provided with a smooth cylindrical surface at the side opposite to its toothed surface comprising a frame,

burnishing means comprising a pair of rotatable members at least one of which is a toothed pinion, means for rotating a toothed one of said rotatable members to drive a ring gear engaged by said members in rotation, means on said frame mounting said rotatable members for relative movement toward and away from each other and generally radially of a ring gear engaged thereby to apply burnishing pressure to the teeth of the ring gear,

means for relatively moving said rotatable members in one direction to a loading position in which a ring gear can be mounted in mesh with said pinion and in the opposite direction to apply burnishing pressure to the teeth of said ring gear,

a pair of pressure rolls,

means on said frame mounting said pressure rolls with their axes parallel to the axes of said rotatable members at opposite sides of a ring gear engaged with said rotatable member for relative movement toward and away from each other generally radially of the gear, and

means for relatively moving said rolls toward and away from each other radially of a ring gear engaged by said rotatable members into pressure contact with the smooth surface thereof to apply ring deforming pressure thereto and to release such pressure at controlled rates in timed relation to rotation of the ring gear.

2. Apparatus as defined in claim 1 in which said pressure rolls are engageable with the smooth surfaces of the ring gear at zones substantially intermediate the zones engaged by said rotatable members.

3. Apparatus as defined in claim 1 in which said ring gear is internally toothed.

4. Apparatus as defined in claim 3 in which said rotatable members are both pinions and said pinions are disposed with one vertically above the other, and the axes of said pressure rolls occupy a horizontal plane substantially midway between said pinions.

5. Apparatus as defined in claim 1 in which the means for relatively moving said rotatable members comprises a lever pivoted to said frame, a piston and cylinder device connected between said frame and one end of said lever, one of said rotatable members being mounted for rotation on said lever.

6. Apparatus as defined in claim 1 in which the means for moving said pressure rolls comprises a pair of arms pivoted to said frame on which said rolls are rotatably mounted.

7. Apparatus as defined in claim 6 comprising resilient means interconnecting said arms, and cam means operable between said frame and both of said arms for forcing said pressure rolls toward a ring gear mounted on said pinions.

8. Apparatus as defined in claim 7 in which said cam means comprises a rotary cam on said frame, cam followers on said arms engageable with opposite sides of said cam, and a vane type fluid pressure motor connected to said rotary cam.

9. Apparatus as defined in claim 6 comprising abutment means acting between said arms to limit relative approach between said rolls and hence the maximum deformations of the ring gear.

10. Apparatus as defined in claim 9, said abutment means comprising a link pivoted at one end to an end of one of said arms, the other end of said link and the adjacent end of the other arm having an adjustable pin and slot connection.

1 1. Apparatus as defined in claim 1 in which said ring gear is externally toothed.

i l i l

Claims

1. Apparatus for simultaneously rounding a ring gear and burnishing its teeth, in which the ring gear may by internally or externally toothed and provided with a smooth cylindrical surface at the side opposite to its toothed surface comprising a frame, burnishing means comprising a pair of rotatable members at least one of which is a toothed pinion, means for rotating a toothed one of said rotatable members to drive a ring gear engaged by said members in rotation, means on said frame mounting said rotatable members for relative movement toward and away from each other and generally radially of a ring gear engaged thereby to apply burnishing pressure to the teeth of the ring gear, means for relatively moving said rotatable members in one direction to a loading position in which a ring gear can be mounted in mesh with said pinion and in the opposite direction to apply burnishing pressure to the teeth of said ring gear, a pair of pressure rolls, means on said frame mounting said pressure rolls with their axes parallel to the axes of said rotatable members at opposite sides of a ring gear engaged with said rotatable member for relative movement toward and away from each other generally radially of the gear, and means for relatively moving said rolls toward and away from each other radially of a ring gear engaged by said rotatable members into pressure contact with the smooth surface thereof to apply ring deforming pressure thereto and to release such pressure at controlled rates in timed relation to rotation of the ring gear.

11. Apparatus as defined in claim 1 in which said ring gear is externally toothed.