Improvements in Ball and Roller Bearings.
Year: 1893

page_text: Date of Application, 27th Feb., 1893
Complete Specification Left, 14th July, 1893-Accepted, 27th Feb., 1894
PROVISIONAL SPECIFICATION.
Improvements in Ball and Roller Bearings.
I, FREDERIC DUMOULIN of 15 Rue des Halles, Paris, France, Engineer, do
hereby declare the nature of this invention to be as follows:-
This invention relates to improvements in ball and roller bearings and is
designed to avoid the friction that usually occurs between the different parts of such
bearings, by arranging the parts so that all their adjacent surfaces shall be in
simple rolling contact.
And in order that the nature of my said invention may be more clearly set forth,
I will proceed te explain the same by reference to the accompanying illustrative
drawings, in which
Figs. 1 and 2 are respectively a longitudinal and a transverse section of a roller
bearing and
Figs. 3 and 4 are corresponding views of a ball bearing, constructed in
accordance therewith.
Figs. 5 and 8 are diagrams hereinafter referred to.
Figs. 6 and 7 illustrate a modified arrangement of the roller bearing shown in
Figs. 1 and 2 and
Fig. 9 illustrates a 'corresponding modification of the arrangement shown in
Figs. 3, and 4.
In each of these figures A represents a shaft; B the lower part of the bearing;
B₁ the cover thereof, C C are the rollers, and DD the balls or spheres, which
collectively are hereinafter referred to as movable supports.
The movable supports C or D are arranged equidistant from each other so that a
polygon whose apices or angles are located at the axes or at the centres of these
supports will be regular. Smaller distance rollers are interposed midway between
and in exact contact with the movable supports yet without touching the walls of
the bearing, so as to regulate or maintain the proper distance apart of said supports
and suppress the sliding friction that takes place in former arrangements, where
these small rollers are in contact both with the periphery of the box and with the
movable supports. These distance rollers are cylindrical as at c in the case of
roller bearings, and conical as at d in the case of ball bearings, and in each case
have cylindrical ends g or has the case may be which work at each side between
two rings Ee or E¹ e¹.
In the case of Figs. 1, 2, 3, 4, the outer rings E or E' are secured to the shaft A
and rotate therewith, whilst the inner rings e are free and are simply carried round
by the distance rollers or cones.
In the modified arrangement. shown in Figs. 6, .7 and 9, the inner rings ef
or ef as the case may be, are fixed to the bearing and are stationary whilst the
outer rings Em or E m² are free and are actuated by the ends of the distance
rollers on which they rest.
In order to prevent longitudinal movement of the shaft, shoulders on the shaft
or end abutments may be provided as in bearings of ordinary construction.
When however either of the arrangements shown in Figs. 1 and 2 or 3 and 4, is
employed the outer rings E or-E! may be utilized for this purpose, together with
the end walls of the bearing.

page_text: With this object circular grooves R and r concentric with the shaft A are
formed symmetrically opposite to one another in each end wall of the bearing and
adjacent ring respectively. Each groove has two inclined or conical faces, and a
plane inner face as shown, the inclined faces of each pair of grooves R, constituting
a ball track for a ball G, or for a series of balls. The said faces are inclined in
such a manner as to avoid any twisting or rubbing action on the ball or balls the
radii of the two rolling circles on the ball being proportional to the radii of the
rolling circles on the said inclined faces. A number of double channels might be
formed, with one ball or a series of balls in each.
The parallelism of the rollers C. and c with the shaft A (Figs. 1, 2, 6, 7)
is ensured by means of annular ribs or projections S on the interior of the bearing
which project into corresponding grooves s formed around each of the rollers C.
In the construction of ball bearings shown in Figs. 3, 4 and 9, the parallelism of
the axis of each distance roller d with that of the shaft, is ensured by the
symmetrical arrangement of the bearing faces H H of the ball track and of the
bearing faces H H of the distance rollers d, the latter being more clearly
indicated in Figs. 5 and 8.
In order to prevent dust from entering the interior of the bearing, a washer L of
material such as leather held in place by a metal ring is provided at each end of
the bearing.
Any suitable lubricant may be employed, for the projections S and the grooves s.
A good lubricant will be necessary for the shoulders of the shaft or for the
end abutments if these be used for preventing endway movement of the shaft instead
of the rings E or E¹ and the end walls of the bearings with rollers G. The radii
of the ends g and h of the distance rollers should be such that their peripheral
velocity is the same as that of the outer rings E or E' or is the same as that
at which they are carried past the fixed inner rings (Figs. 6, 7, and 9).
Dated this 27th day of February 1893).
COMPLETE SPECIFICATION.
Improvements in Ball and Roller Bearings.
İ, FREDERIC DUMOULIN of 15 Rue des Halles, Paris, France, Engineer, do
hereby declare the nature of this invention and in what manner the same is to be
performed to be particularly described and ascertained in and by the following
statement:-
This invention relates to improvements in ball and roller bearings and is designed
to avoid the friction that usually occurs between the different parts of such bearings,
by arranging the parts so that all their adjacent surfaces shall be in simple rolling-
contact.
And in order that the nature of my said invention may be more clearly set forth,
I will proceed to explain the same by reference to the drawings filed with my
Provisional Specification in which,
Figs. 1 and 2 are respectively a longitudinal and a transverse section of a roller
bearing; and
Figs. 3 and 4 are corresponding views of a ball bearing, constructed in accordance
therewith.
Figs. 5 and 8 are diagrams hereinafter referred to.
Figs. 6 and 7 illustrate a modified arrangement of the roller bearing shown in
Figs. 1 and 2, and
Fig. 9 illustrates a corresponding modification of the arrangement shown in
Figs. 3 and 4.

page_text: In each of these figures A represents a shaft; B the lower part of the bearing
B¹ the cover thereof. CC are the rollers, and DD the balls or spheres, which
collectively are hereinafter referred to as movable supports.
The movable supports C or D are arranged equidistant from each other so that
a polygon whose apices or angles are located at the axes or at the centres of these
supports will be regular. Smaller distance rollers are interposed midway between
and in exact contact with the movable supports yet without touching the walls of
the bearing, so as to regulate or maintain the proper distance apart of said
supports and suppress the sliding friction that takes place in former arrangements
where these small rollers are in contact both with the periphery of the box and with
the movable supports. These distance rollers are cylindrical as at c in the case of
roller bearings, and conical as at d in the case of ball bearings, and in each case
have cylindrical ends 9 or 1 h as the case may be which work at each side between
two rings Ee or E' e¹.
'
In the case of Figs. 1, 2, 3, 4, the outer rings E or E' are secured to the shaft A
and rotate therewith, whilst the inner rings e are free and are simply carried round
by the distance rollers or cones.
In the modified arrangement shown in Figs. 6, 7 and 9, the inner rings e for e¹ fl
as the case may be, are fixed to the bearing and are stationary, whilst the outer
rings Em or E m² are free and are actuated by the ends of the distance rollers on
which they rest.
;
In order to prevent longitudinal movement of the shaft, shoulders on the shaft or
end abutments, may be provided as in bearings of ordinary construction.
When however either of the arrangements shown in Figs. 1 and 2 or 3 and 4,
is employed, the outer rings E or E' may be utilized for this purpose, together with
the end walls of the bearing.
With this object circular grooves R and r concentric with the shaft A are formed
symmetrically opposite to one another in each end wall of the bearing and adjacent
ring respectively. Each groove has two inclined or conical faces, and a plane
inner face as shown, the inclined faces of each pair of grooves R r constituting a
ball track for a ball G, or for a series of balls. The said faces are inclined in such a
manner as to avoid any twisting or rubbing action on the ball the radii of the two
rolling circles on the ball being proportional to the radii of the rolling circles on the
said inclined faces. A number of double channels might be formed, with one ball or
a series of balls in each.
The parallelism of the rollers C and c with the shaft A (Figs. 1, 2, 6, 7) is
ensured by means of annular ribs or projections S on the interior of the bearing
which project into corresponding grooves formed around each of the rollers C.
In the construction of ball bearings shown in Figs. 3, 4 and 9, the parallelism
of the axis of each distance roller d with that of the shaft, is ensured by the
symmetrical arrangement of the bearing faces H H of the ball track and of the
bearing faces H'H' of the distance rollers d, the latter being more clearly indicated
in Figs. 5 and 8.
In order to prevent dust from entering the interior of the bearing, a washer L of
material such as leather held in place by a metal ring is provided at each end of the
bearing.
Any suitable lubricant may be employed for the projections S and the grooves s.
A good lubricant will be necessary for the shoulders of the shaft, or for the end
abutments if these be used for preventing endway movement of the shaft instead
of the rings E or E' and the end walls of the bearings with rollers G. The radii
of the ends g and h¹ of the distance rollers should be such that their peripheral
velocity is the same as that of the outer rings E or E' or is the same as that at which
they are carried past the fixed inner rings (Figs. 6, 7 and 9)..
Assuming that the study of the motion allows when the diameters are known, of
also ascertaining accurately the number of revolutions of the supporting rollers or
balls about their axes or centres, as also the paths travelled by said axes or centres
whilst the shaft is making one revolution and that the number of revolutions of

page_text: T
een distance roller and the number of revolutions of each movable support are
inversely proportional to the radii of the circles or surfaces at which said parts
touch one another, it follows that the diameter of the ends g g of the regulating
parts, the internal diameter of the outer rings E E' and the external diameter
of the inner rings e e¹, can be accurately determined in order that the motion 5
between the said three parts shall be wholly simple rolling motion.
Thus in the arrangement shown in Figs. 1 and 2, assuming the radius of the
journal A to be M004 then for one revolution of the journal, that is to say for a
distance travelled equal to 2 π x M 004 of a point of its periphery, the distance
2 π × 0.04, that is M0.04π;
travelled by the centre of a supporting roller C will be
2
the fraction of a revolution made by the ring of supporting rollers C, assuming it
0.04 TT
to have a radius of M 0.07 will be
that is ths; the number of revolu-
2 π × 0.07
tions about its own axis made by each supporting roller. C, assuming the inner
surface of the bearing against which the supporting rollers travel to a have a radius
made
×
× 2 × 0.10
2fths; and 1
2 π × 0.03
by each distance roller c,
0.03
0.005
that is 40ths.
of M 0.10 and the rollers a radius of M 0.03, will be
the number of revolutions about its own axis
assuming it to have a radius of 0·005, will be 3
If the distance of the centre of each distance roller c from the axis of the shaft A
be 0:06062 and be the required radius of the ends g of each of the supporting
rollers, then the radius of such ends and the internal diameter of the outer
rings E E¹ and the external diameter of the inner rings e e¹ can be obtained by the
following equations. x. 2 (0:06062 + x) = 40 × 2, whence we find
M 0.00866. The internal radius of the outer rings E or E¹ is therefore
0-06062 +0-00866 = 0.06928, and the outer radius of the inner rings e e
is 0.06062 0.00866 = 0-05196.
2 π × 0.064
that is. Boths.
In the bearing shown in Figs. 6 and 7, the distance traversed by the centre of a
supporting roller C for one revolution of the journal A, assuming the latter has
a radius of M 0.04, as before, is M 0.04 π, and the fraction of a revolution made by
0.04 π
the ring of rollers, assuming it to have a radius of 0.064, is
The number of revolutions about its axis made by a supporting roller C assuming
the inner surface of the bearing against which the supporting rollers C travel, to
have a radius of 0.088 and the said rollers a radius of 0.024, will be 18 × 2 π × 0.088
2 x 0.024
that is ths; and the number of revolutions about its own axis made by each'
distance roller c, assuming it to have a radius of 0.008, will be 18 x 0.008
that is ths.
-0.024
Hence if M 0-055424 be the distance of the centre of each distance roller from_
the axis of the shaft A and be the required radius of the ends g of each of the
supporting rollers, then the radius of such ends and the internal diameter of the
outer rings Em and the external diameter of the inner rings ef can be obtained by
the following equation & x 2 (0.055424-x)=2 whence = M 0.004619.
The internal radius of the outer rings E m is therefore M 0-055424 + M0-004619
M0.060043, and the outer radius of the inner rings e fis M 0.055424 M 0.004619
M 0.050805.
-
Similar calculations are made for 'determining, in the case of the ball-bearings,
the radius of the cylindrical ends of the distance rollers, and the radius of the rings
between which they work, bearing in mind however that each supporting: ball rolls
on the journal A along a circumference of a great circle, whilst it rolls on the
inclined faces of the journal box along two smaller circles parallel to the great circle,
and located symmetrically at each side thereof.

page_text: Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is:-
1. In a bearing, the combination of the rollers C arranged as described and having
circular grooves ss in which engage the projections S S, the regulating pieces c
with ends g g, of determined radius, the ring E fixed to the shaft and the movable
inner ring e, the whole constructed and arranged substantially as described and
shown.
2. In a ball bearing, the combination of the balls D, the symmetrically inclined
bearing faces H, H' the regulating pieces d with end bearing parts h h of calculated
radius, the ring E or E fixed to the shaft, and the movable inner ring e
substantially as described.
3. In a bearing, the combination with the parts specified in Claim 1, or in Claim 2,
of a ball G arranged between the ring E or E' and the transverse face of the box
of the bearing and between two symmetrically and oppositely arranged grooves R
and r, having inclined faces substantially as described.
4. In a bearing the combination of the roller C arranged as shown and formed
with circular grooves ss in which engage the fixed projections S S, the distance
rollers c with ends g g of calculated radius, the movable outer ring E m and the
inner ring ef fixed to the box of the bearing substantially as described.
5. In a bearing the combination with the balls D of the symmetrically inclined
supporting surfaces H, H' the distance rollers d having supporting ends h h of
determined radius, the movable outer ring E m', and the inner ring ef¹ fixed to the
bearing substantially as described.
6. The improved ball and roller bearings constructed and arranged as herein-
before described with reference respectively to and shown in Figs. 1 and 2; in
Figs. 3 and 4; in Figs. 6 and 7; and in Fig. 9 of the accompanying drawings.
Dated this 14th day of July 1893.
F. DUMOULIN,
By L. W., per F. B.