Tooling apparatus

A tooling apparatus having a main somewhat hollow yoke-like housing adjustably positionable in micrometer increments relative to a supporting base member which may be readily and fixedly attached to the lathe bed. The yoke housing is provided with an enlarged opening for receiving a rotating assembly including a plurality of radially adjustable jaw members adapted for engaging the outer surface of an elongate work piece for retention of the work piece within the jaws thereof. The jaw members may be adjusted in micrometer increments for precise positioning of the work piece relative to the opening thereof, and relative to the lathe chuck, either centrally relative thereto, or offset therefrom. The housing and rotating jaw assembly are sealed and provided with bearings therein to permit rotation while enabling passage of fluid through hollow openings therein for enabling lubrication and cooling to permit high speeds of rotation 20 during machining of a work piece supported by the lathe chuck and the apparatus.

BACKGROUND OF THE INVENTION 
The background of the invention will be discussed in two parts: 
1. Field of the Invention 
This invention relates to tooling apparatus, and more particularly to an 
indicating center support apparatus for use with a machine lathe or the 
like. 
2. Description of the Prior Art 
In the machine cutting of long work pieces of cylindrical cross-section 
supported between a chuck and a tail stock, some means of support may be 
required at a mid-point of the work piece in order to avoid excess 
vibration during the machining or cutting operation. Alternatively, very 
slow speeds of rotation of the work piece may be required to prevent such 
vibration or chattering during cutting operations. In most instances, the 
precision and the accuracy of the cut may be affected. 
Prior art devices for use with machine tools such as cutting lathes for 
supporting long work pieces have included a device referred to as a steady 
rest. The steady rest is a device which may be attached to the bed of the 
lathe, and is provided with a central opening through which extends the 
work piece. Within the central opening, there are a plurality of rollers 
on arms with the rollers engaging the outer surface of the work piece. 
Such steady rest devices are suited for cylindrical work pieces only, and 
afford little in the way of adjustment, but serve a primary purpose of 
simply supporting a cylindrical work piece having one end thereof secured 
within the chuck of the lathe. The steady rest support is generally 
positioned in proximate relation to the cutting tool. With such a steady 
rest, if the work piece is being machined, such as with a cutting tool, 
the other end of the work piece is preferably supported within a tail 
stock. Such steady rests have been virtually unusable for precision 
cutting of a long work piece supported at only one end by the chuck. 
Furthermore, if the machining operation is to be performed with a 
non-cylindrical work piece, or if the work piece is to be offset or 
eccentric relative to the lathe chuck, a steady rest cannot be employed. 
It is an object of the present invention to provide a new and improved 
tooling apparatus for support of a long work piece during cutting and 
machining operations. 
It is another object of the present invention to provide a new and improved 
tooling apparatus for securely and rotatably supporting a long work piece 
of cylindrical or other cross-section. 
It is still another object of the present invention to provide a new and 
impoved tooling apparatus which enables support of an offset positioned 
long work piece within the chuck of a lathe with or without use of a 
tailstock, while enabling rotation of the work piece for precision 
eccentirc cuts. 
SUMMARY OF THE INVENTION 
The foregoing and other objects of the invention are accomplished by 
providing a tooling apparatus having a main somewhat hollow yoke-like 
housing adjustably positionable in micrometer increments relative to a 
supporting base member which may be readily and fixedly attached to the 
lathe bed. The yoke housing is provided with an enlarged opening for 
receiving a rotating assembly including a plurality of radially adjustable 
jaw members adapted for engaging the outer surface of an elongate work 
piece for retention of the work piece within the jaws thereof. The jaw 
members may be adjusted in micrometer increments for precise positioning 
of the work piece relative to the opening thereof, and relative to the 
lathe chuck, either centrally relative thereto, or offset therefrom. The 
housing and rotating jaw assembly are sealed and provided with bearings 
therein to permit rotation while enabling passage of fluid through hollow 
openings therein for enabling lubrication and cooling to permit high 
speeds of rotation during machining of a work piece supported by the lathe 
chuck and the apparatus. 
Other objects, features and advantages of the invention will become 
apparent from a reading of the specification when taken in conjunction 
with the drawings, in which like reference numerals refer to like elements 
in the several views.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring now to the drawings, and particularly to FIG. 1, there is shown a 
prior art steady rest 15 mounted on the bed of a lathe 16. The steady rest 
15 includes a generally U-shaped supporting base member 17 securable to 
the bed of the lathe 16, with a pivotable generally U-shaped upper member 
18 configured for defining an enlarged center opening 20 into which 
extends a plurality of arm members 21a, 21b and 21c, with each arm member 
having a roller bearing 22a, 22b and 22c, respectively rotatably attached 
to the end thereof, the arm members being displaced 120 degrees apart. 
Each of the arm members 21a, 21b and 21c includes a block portion 23a, 
23b, and 23c, respectively, each being slidably mounted within a machined 
slot in one of the base member 17 and upper member 18, with radial 
positioning of the arm members 21a, 21b and 21c being accomplished by 
adjustment bolts 24a, 24b and 24c, respectively. The roller bearings 22a, 
22b and 22c are positioned for rolling contact with the surface of a 
cylindrical work piece by adjusting the position of the arm members 21a, 
21b and 21c relative to the base and upper members 17 and 18. 
In operation, the upper member 18 is hinged out of the way and a work piece 
is positioned within the enlarged opening 20 where it rests on the 
bearings 22b and 22c of the two lower arm members 21b and 21c. The upper 
member 18 is then pivoted to a closed position as shown, and a locking 
bolt 25 is passed through aligned apertures in the flanges opposite the 
hinge for securing the upper and base members 18 and 17 together. The work 
piece has one end thereof secured within a chuck 29 which attaches to the 
driven block of the lathe 16, with the other end secured for rotation by 
means of a tailstock (not shown), with the steady rest 15 intermediate the 
ends of the work piece. The steady rest 15 simply provides a measure of 
support for the supported portion of a cylindrical work piece. 
With such steady rests 15, only cylindrical work pieces may be employed, 
and the work piece must be positioned on the center of rotation of the 
lathe head 16a. That is, the steady rest 15 cannot be employed when a work 
piece is supported by a four jaw chuck or the like with the center thereof 
offset from the center of rotation. As the work piece rotates for cutting, 
the bearings 22a, 22b, and 22c, being of small diameter, are rotating at 
speeds which are many times greater than the speed of rotation of the work 
piece, which generates heat within the bearings, oftentimes resulting in 
binding or seizure of the bearings. 
Although a steady rest 15 may be utilized with or without a tail stock, to 
enable use of the steady rest 15, a work piece must first be prepared, and 
this preparation entails center drilling of the end to be held by the 
tailstock, this center drilling being performed by hand. Then, a register 
is turned, this operation involving the smoothing or surface finishing of 
that part of the work piece to be received within the steady rest. If 
smoothing is not performed correctly, and the work piece is to be cut or 
machined, and surface defect at the point of contact of the roller 
bearings 22a, 22b and 22c, will affect the cut detrimentally. 
While face cutting may be performed with the steady rest 15 by supporting 
one end of a cylindrical work piece within a chuck and the other end by a 
steady rest 15, the depth of cut is minimal, at about 0.050 to 0.070 inch. 
In addition, face cutting with a steady rest 15 is not advisable where 
accuracy is required. For surface or diameter cutting of a work piece, the 
depth of cut is likewise limited to depths of about 0.100 inch on the side 
or 0.200 on the diameter. During either face or diameter cutting with use 
of a steady rest 15, pressure is exerted on the work piece surface by the 
cutting tool. This pressure, in turn, causes twisting of the roller 
bearings 22a, 22b and 22c, and likewise moves the work piece away from the 
roller bearing located on the same side as the cutting tool. 
For example, by reference to FIG. 1, if the work piece is set up for 
surface cutting with the cutting tool positioned on the side of the lathe 
16 nearest arm 21c, the work piece will be urged away from bearing 22c. 
This movement of the work piece toward the other two bearings 22a and 22b 
causes torsional stresses in the bearings 22a and 22b, that is, a twisting 
about the longitudinal axes of the arms 21a and 21b. As the work piece is 
rotated, it attempts to return to its original position, and with the 
twisted bearings, the work piece tends to ride out of the chuck. In 
addition, chattering, or vibration, occurs at the point of contact of the 
roller bearings 22a and 22b with the surface of the work piece, with the 
vibration hammering at the slide blocks 23a and 23b, thereby loosening the 
adjustment bolts 24a and 24b. To complicate matters, the tolerances of 
such small diameter roller bearings may be one to two thousandths of an 
inch, and with the rapid rotation of the bearings relative to the rpm of 
the lathe, additional tolerance is rapidly induced by premature wear of 
the rollers within the bearings. By way of example, with a one inch 
diameter roller bearing 22a and an eight inch work piece, the rotation of 
the roller bearing 22a will be eight rotations for one rotation of the 
work piece. With the lathe 16 rotating at 110 rpm for this work piece, the 
roller bearing 22a will be rotating at 880 rpm, thus generating heat 
within the low tolerance bearings. 
In many instances, during surface or face cutting, the removed chips tend 
to fly, oftentimes lodging between the roller bearings 22a, 22b and 22c, 
and the smooth surface of the work piece. The chips then damage this 
surface, and when the surface finish is critical, such marring or 
scratching of the surface is unacceptable. As a consequence of the many 
inherent limitations and problems with the steady rest 15, its use has 
been severely limited to rough, non critical or low accuracy jobs, or to 
the machining of work pieces in which surface finish is not critical. 
Furthermore, even with a cylindrical work piece, the steady rest 15 cannot 
be used with a dial indicator for ensuring accurate center positioning of 
a cylindrical work piece, due to the loose tolerances employed in such 
devices. For screw thread cutting, such as API threads of 3 to 5 threads 
per inch with a taper of 2" to 3" per foot, a steady rest cannot be 
employed at all. 
In accordance with the invention to be described, however, all of the 
disadvantages of the steady rest have been overcome. An indicator may be 
used to center the work piece within normal machining precision tolerances 
without use of a tail stock; chattering and vibration are eliminated; cuts 
of 0.250 on the face and 0.900 on the diameter of a work piece may be 
readily achieved with normal machining precision; API threads can be 
accurately cut; center drilling of the work piece is not required; turning 
of a register is not required; the surface finish is not marred or 
scratched during cutting or machining; noncylindrical work pieces can be 
readily machined; and the work piece can be offset for eccentric machining 
or cutting. 
Referring now to FIG. 2, there is shown the tooling apparatus, generally 
designated 30, in accordance with the present invention, in which the 
tooling apparatus 30 may be used in lieu of a tail stock to support one 
end of a work piece 28 with the other end within the chuck 29 of the lathe 
16. Cutting and machining operations may be performed on either side of 
the apparatus 30, that is intermediate the chuck 29 and apparatus 30, or 
on the end or face of the work piece 28 in overhanging relation to the 
apparatus 30, such as illustrated by the cutting tool 31 machining the 
face 28a of the work piece 28. 
Briefly, referring to FIGS. 2 and 3, the apparatus 30 includes a base 
assembly of a lower base 32 and an upper base 34, the bases being adapted 
for securing to each other and to the bed of the lathe 16; a housing yoke 
35 attachable for adjustment relative to the upper base 34; a rotating jaw 
assembly, generally designated 36, which includes a front plate member 38, 
a rear plate member 39, and a plurality of jaw assemblies 40-43, radially 
slidable relative to the front plate member 38, and interior components 
which will be described hereinafter. Means, such as hoses 45 are coupled 
to the yoke housing 35 for passage of cooling fluids through passageways 
formed on the interior of the yoke housing 35 as will be described. With 
the exception of seals, all of the parts are formed of machined metal, 
such as steel or aluminum, or suitable alloys with good thermal 
conductivity. 
In essence, the front and rear plate members 38 and 39 are coupled together 
to form a hub-like rotatable assembly with enlarged hub flanges 
surrounding the sides of the housing yoke 35, with the interior portions 
and surfaces suitably machined or milled to provide internal cooling and 
lubrication, with the jaw assemblies 40-43 being radially adjusted to grip 
the surface of the work piece 28, the plate members 38, 39 and jaw 
assemblies 40-43 then rotating concurrently with the work piece 28. As 
will be described, micrometer adjustments are provided for minute 
adjustment of the positions of the upper base relative to the lower base, 
as well as adjustments of the positions of the jaw assemblies 40-43 
relative to the work piece. 
Inasmuch as the work piece 28 is supported within the enlarged opening 44 
of the rotating jaw assembly 36, a dial indicator may be used for accurate 
positioning of the work piece 28 relative to the axis of rotation thereof. 
Furthermore, with the rotating jaw assembly 36, the work piece 28 may be 
positioned on the lathe chuck 29 offset from the center thereof, and 
supported and rotated by the rotating jaw assembly 36 offset from the 
center thereof. Additionally, a non-cylindrical work piece 28 may be 
machined or cut using the tooling apparatus 30 with a four jaw chuck 29 on 
the lathe 16. 
Referring now to FIGS. 3 and 4, there is shown in plan and cross-section, 
the tooling apparatus 30, with portions thereof removed and cut away to 
illustrate the interior components. The front plate 38 has an enlarged 
generally washer-shaped front surface with an enlarged central opening 44 
through which the work piece 28 extends for having the surface thereof 
engaged by and retained by the jaw members 40-43. As best illustrated in 
FIG. 4, each of the jaw members 40-43 is identically configured and 
includes a jaw slide member and a micrometer adjusting screw received 
within a slotted radially extending opening in the front plate member 38. 
The slotted openings are designated 38a, 38b, and 38c, and are configured 
with side slots for enabling sliding of the slide jaw members, two of 
which are shown and designated 42a and 43a, the positions of which are 
radially adjustable by means of adjusting screws 42b and 43b, which coact 
between threaded semicircular slots in the bottom of the rounded portion 
of slots 38a, 38b and 38c, and mating semicircular rounded slots in the 
adjacent surface of the jaw slide members 42a, 43a, etc. The jaws 40-43 
are suitably attached to the jaw slide members, such as slide member 43a 
by such means as cap screws 43c and 43d. 
As depicted in FIGS. 4 and 7, the front plate member 38 is configured with 
a central axially extending hub portion 46 which is lapped and internally 
threaded at 48 to coact with and receive a smaller threaded hub portion 50 
of the rear plate member 39, the two parts thus being joined to form a 
rotatable hub with a central opening 44 with large diameter flanges of 
approximately the same diameter as the outer diameter of the housing yoke 
35. The flange portions of the front and rear plate members 38 and 39, as 
assembled have the inner surfaces thereof in proximate relation to the 
axially outer front and rear edges of the housing yoke 35. 
As shown in FIG. 4, the hub 46 of front plate 38 is configured for 
receiving thereon first and second enlarged diameter Timken bearings 52 
and 53. The outer circumference of the bearings 52 and 53 are held in 
spaced relation on the shoulders 54 of the yoke 35 due to the intervening 
web portion 55 (See also FIGS. 5 and 6), while the inner circumference of 
the bearings 52 and 53 abut against the hub 46 of the front plate member 
38 of the rotating jaw assembly 36. 
A generally annular washer-shaped tension plate 57 is threadably secured to 
the outer end of the hub portion 46 of the front plate member 38 for 
maintaining and pre-loading the bearings 52 and 53 in position relative to 
the hub portion 46. For securing the tension plate 57, the inner 
circumference is suitably threaded for matingly engaging like threads 
formed on the outer surface of the outer edge 47 of the hub portion 46 of 
the front plate member 38. A set screw (not shown) is passed through a 
threaded aperture in the tension plate 57 for abutting against the side 
surface of the adjacent bearing 54. 
As depicted in FIGS. 4 through 6, the inner opposite surfaces of the yoke 
35 are machined radially outwardly of the bearings 52 and 53 to provide 
first and second annular shoulders 35a and 35b, with the adjacent surfaces 
of the plate members 38 and 39 being spaced therefrom and provided with 
inwardly extending axially opposed tapered annular flanges 58 and 59, 
respectively. These flanges 58 and 59 along with adjacent surfaces of the 
shoulders 35a and 35b form annular grooves configured for receiving 
therein annular oil seals 60 and 61, respectively, these seals having a 
generally L-shaped cross-section with a neoprene or rubber like portion 
for abutting with the adjacent surface of the flanges 58 and 59 to provide 
a sealed inner lubrication material containing compartment 35c within the 
interior of the portion of the apparatus between the yoke 35 and the hub 
46 of the rotating jaw assembly 36. 
To facilitate and cooling of the apparatus 30 during use thereof, as shown 
in FIG. 3, a generally peripheral separate cooling channel 62 is formed in 
the outer surface of the yoke 35 such as by machining, the length of the 
channel 62 traversing approximately 240 degrees of the periphery of the 
yoke 35. After machining, the channel 62 is sealed by a metal band 63 
positioned on shoulders 63a formed on opposite sides of the channel 62. 
The metal band 63 may be welded or affixed by any conventional method to 
provide a fluid tight channel 62. At opposite ends of the channel 62, hose 
fittings 45a are threadably attached to openings which communicate with 
the channel 62 with the fittings 45a being attached to suitable hoses 45 
for conducting cooling fluid through the channel 62 for cooling of the 
apparatus during rotation. 
For purposes of lubrication of the bearings 52 and 53, a fitting 56 is 
provided in the upper central portion of yoke 35 for enabling the 
insertion of a suitable lubricant, such as oil, into the interior annular 
lubricating compartment 35c which generally houses the bearings 52 and 53, 
with the lubricant being contained therein by seals 60 and 61. After 
insertion of the lubricant, the fitting 56 is suitably capped with a screw 
member 56a. This lubrication compartment 35c is physically separate from 
the cooling channel 62, but excellent heat transfer is obtained due to the 
construction of the parts from thermally conductive material, such as 
suitable steel or aluminum alloys. 
By reference to FIG. 4, the channel 62 and the flanges 58 and 59, as well 
as the interior surfaces of the assembled parts are constructed in such a 
way that the lubricant is wholly contained within compartment 35c, which 
wholly contains the bearings 52 and 53, with the flanges 58 and 59 being 
constructed so that the edges thereof are in close proximate relation to 
adjacent edges of the housing 35 of the annular channels supporting the 
seals 60 and 61 to provide minimal openings into these annular channels 
and thus minimize the force exerted on the seals 60 and 61 while 
maximizing the sealing of the rotating jaw assembly 36. 
As shown in FIG. 8, for enabling minute adjustments of the yoke 35 relative 
to the bed of a lathe 16, the lower base member 34 is secured to the bed. 
The upper surface of the lower base member 32 is provided with first and 
second longitudinally aligned recesses 64 and 65 into which extend 
depending lugs 66 and 67, respectively, of the upper base member 34. 
Longitudinally extending apertures 68 and 69 in the lower base member 32 
align with threaded apertures 70 and 71, respectively, in the depending 
lugs 66 and 67 of the upper base member 32 for engagement with screw 
members 72 (only one of which is shown). The recesses 64 and 65 have a 
length greater than the corresponding dimension of the lugs 66 and 67 for 
enabling adjustment of the upper base member 34 relative to the lower base 
member 32 by adjustment of the screws 72. 
Similarly, adjustment in an orthogonal direction is accomplished by 
dovetail members 74 and 76 formed in the upper surface of upper base 
member 34 slidably coacting with matingly formed slots 78 and 80 formed in 
the lower edge of yoke 35 (See FIG. 3). As shown in FIG. 3, the slots 78 
and 80 are slightly oversized in the transverse direction and are fitted 
with gib plates 79 and 81, respectively, with screw members 82 and 84 
threadably fitted between the gib plates 79 and 81 and the adjacent 
portion of the yoke 35. 
For securing the base assembly of FIG. 8 to the lathe, the lower base 
member 32 is provided with a centrally positioned threaded aperture 90 for 
receiving a screw member 92 which is passed through a clamp block 94 
beneath the rails of the lathe bed. Tightening the screw 92 of the clamp 
block 94 attached to the base assembly secures the tooling apparatus 30 on 
the lathe 1 as depicted in FIG. 2. 
In operation of the tooling apparatus 30, as shown in FIG. 2, the work 
piece 28 is secured within the chuck 29, with the work piece 28 extending 
through the enlarged opening 44 of the apparatus 30. The jaws 40-43 are 
adjusted into clamping engagement with the outer surface of the work piece 
28. An eccentricity dial gauge (not shown) may then be secured relative to 
the lathe 16 with the arm thereof in contact with the surface of the work 
piece 28, and the work piece 28 then slowly rotated, with micrometer 
adjustments of the jaws 40-43 being effected to position the work piece at 
the true center of rotation of the rotating assembly 36 with the accuracy 
normal to such gauges, that is, within one half of a thousandths of an 
inch or better. This type of accuracy is not obtainable with the prior art 
steady rest since the tolerances of the small diameter bearings 22 at the 
ends of the arms 21 thereof, initially have looser tolerances, and with 
age the tolerance slackens substantially. 
With the tooling apparatus 30 according to the invention, a tailstock is 
not needed, and the cutting can be accomplished at an overhanging end of 
the work piece 28, as depicted in FIG. 2, with the same degree of 
precision as cutting at a more central location with the work piece 
supported by a tailstock. 
With the bearings 52 and 53 contained within the sealed lubrication 
compartment 35c, and with a separate cooling channel 62, higher speeds of 
rotation of the work piece 28 may be utilized for precision maching and 
cutting, thus significantly reducing the time required for such 
operations. Although four jaw members 40-43 have been depicted for 
enabling off-center positioning and rotation of the work piece 28, it is 
to be understood that the tooling apparatus 30 may be provided with three 
such jaw members if it is to be used solely with work pieces having the 
axis of rotation thereof on the axis of rotation of the lathe. 
While there has been shown and described a preferred embodiment, it is to 
be understood that various other adaptations and modifications may be made 
within the spirit and scope of the invention.