Bearing extracting tool

A bearing extracting tool comprising a reaction housing adapted to be placed against machinery wall structure around the end of a shaft and bearing assembly to exract the bearing assembly; an end plate on the end of the housing away fom the bearing assembly; a plurality of lifter bars with lifter elements on one end thereof and abutment members adjustably secured thereto; a lifter plate generally parallel to the end plate and disposed externally of the reaction housing; and a force applying driver member. The lifter bars extend through the reaction housing, reaction housing end plate and the lifter plate with the abutmemt members secured to the lifter bars beyond the lifter plate, but in abutment therewith. The force applying driver member extends through the lifter plate with one end applied to the reaction housing end plate and a free end accesible to a driving force tending to urge the lifter plate, the abutment members and lifter bars away from the reaction housing whereby a bearing assembly may be extracted from machinery in which it is disposed.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to an apparatus or tool for disassembling 
machinery elements for repairs and/or replacement and in particular to an 
apparatus for removing a bearing assembly from around the end of a shaft 
and from the surrounding supporting portion of the machinery housing. 
2. Description of the Prior Art 
Prior art apparatuses most closely exemplifying the state of the art of the 
subject matter of the present invention are believed to include United 
States patents of Howell, U.S. Pat. No. 1,670,573 and Kuffner, U.S. Pat. 
No. 3,605,242. Howell and Kuffner both are considered to be relevant prior 
art in that they disclose bearing pulling devices comprising a plurality 
of pulling bars with pulling lugs or protuberances on ends that are 
inserted between the bearing races, a jack screw for applying a lifting 
force to a cross member operatively connected to the pulling bars. 
While prior devices may work well for the specific intended purpose 
thereof, actual use through experience reveals problems or disadvantages 
not heretofore considered. In this connection, it is noted that the jack 
screws of both Howell and Kuffner are positioned with one end applied 
against the shaft from which the bearing assembly is to be removed. Where 
the shaft has a small diameter or is not sufficiently sturdy, damage could 
be inflicted to the shaft by such bearing pulling apparatus. 
SUMMARY OF THE INVENTION 
The present invention comprises a new and improved apparatus or tool for 
disassembling machinery elements, in particular for extracting a bearing 
assembly. 
One object of the present invention is to provide a new and improved 
apparatus for extracting a bearing assembly including inner and outer race 
members thereof from around the end of a shaft and the surrounding 
machinery housing wall or support portions. 
Another object of the present invention is to provide an extractor 
apparatus whereby no force or reaction is directed against the end of the 
shaft from which bearing elements are to be removed. 
Still another object of the present invention is to provide an improved 
bearing assembly removing apparatus whereby the force for removing the 
bearing assembly is distributed over a wide area rather than concentrated 
on the end of the shaft which could be bent where the shaft is relatively 
small or weak. 
With the foregoing objects in mind, applicants have developed a new and 
improved apparatus for extracting a bearing assembly including inner and 
outer race members from around the end of the shaft and surrounding 
support structure or machinery housing.

DETAILED DESCRIPTION OF THE INVENTION 
Referring now to the drawings with greater specificity and in particular to 
FIGS. 1 and 2, the reader will readily appreciate that the present 
invention is an apparatus or tool 10 for extracting a bearing assembly 16 
including, for example, an inner race 15 and an outer race 17, as 
illustrated in phantom in FIG. 1. Bearing extracting tool 10 comprises a 
reaction member in the form of housing 12, which for convenience in an 
open bottom, hollow tubular shell 20. Shell 20 includes a lower edge 22 
which defines open end 24. Windows 25 are provided in the side of shell 
20. Extracting tool 10 also comprises force receiving means at the free or 
upper end of shell 20 in the form of a first plate 26 lifter means 28 
including a second plate 29, a jack screw or force applying bolt 30, and a 
plurality of lifter rods or bars 32. First plate 26 is seen in FIG. 2 to 
be firmly seated over the upper end of shell 20 and may be optionally 
removable or secured thereat. Jack screw or force applying bolt 30 is 
formed with a pilot end 34 which in operation is seated in pressing 
relationship in countersunk pilot seat portion 36 formed on the upper side 
of first plate 26. 
Plates 26 and 29 formed with a plurality of sets of aligned perforations 
38, 38', 38" and 40, 40', 40", respectively, through which a lifter bar 32 
may extend. As may be seen in FIG. 1, the perforations 38 and 40 are 
formed for convenience at about the same radial distance from the centers 
of plates 26 and 29, respectively, and perforations 38' and 40' and 
perforations 38" and 40" formed at progressively greater radial distances 
from the centers of plates 26 and 29 respectively. Second plate 29 
includes a threaded bore 42 in which bolt 30 is threadedly received. 
Lifter rods 32 are threadedly secured to nuts 44 supported on the upper 
side of second plate 29. Nuts 44 may be optionally permanently secured to 
plate 29 or may be merely loosely supported on the upper side of plate 29. 
Lifter rods or bars 32 are also provided with an enlarged lifting end 46 
including a partically spherical surface 48 and opposed parallel flat 
surfaces 50 which are formed in place of portions removed or omitted from 
the sphere that otherwise are continuous along spherical surface 48. As 
may be seen in FIG. 6, lifting end 46 is formed or provided in offset or 
eccentric relationship on the end of lifter bar 32. Alternatively, as 
illustrated in FIG. 6A, instead of the construction of lifter rod 32, a 
lifter rod 32" may be provided with an enlarged lifting end 46" without 
offset, but in centered relationship with the axis of lifter rod 32" so 
that lifter rod 32" extends from end 46" centrally between parallel flat 
surfaces 50",50" and between opposite sides of spherical surface 48". 
In another alternate embodiment of the disclosed invention, a lifter rod 
32' is illustrated in FIG. 8 with an arrangement of a plurality of such 
rods 32' appearing in FIG. 7. Rod 32' is provided with an enlarged lifting 
end 46' at the lower end thereof which is formed with a partial spherical 
surface 48' extending around end 46' and parallel flat surfaces 50',50' 
extending in generally vertical planes where portions have been omitted 
from the sphere which would otherwise extend continuously around from 
spherical surface 48'. At the upper end of rod 32' a slot 33' is provided 
which slot 33' extends parallel to the flat surfaces 50',50' of lifting 
end 46'. 
METHOD OF OPERATION 
With a clear understanding of the various parts making up extractor tool 10 
described above, it will now be understood that lifter bars 32 may be 
inserted into selected aligned perforations 38, 40 or 38', 40' or 38" or 
40" of plates 26, 29, respectively, depending upon the size of the bearing 
assembly 16 that is to be extracted. To use extractor tool 10, one should 
first cut and pry out ball retainer normally provided in bearing assembly 
16, after which the ball bearing elements will roll together and leave 
sufficient space for insertion of lifter ends 46 of lifter bars 32. Lifter 
ends 46 are inserted with flat surfaces 50 along the adjacent edges of 
inner race 15 and outer race 17 of bearing assembly 14 as may be seen in 
FIG. 4 prior to being adjusted to lifting condition. Lifter ends 46 may be 
adjusted to lifting condition simply by rotating lifter bars 32 ninety 
degrees or a quarter of a turn so that the spherical surfaces 48 will 
contact the arcuate groove portions of race members 15 and 17. Each bar 32 
is inserted at circumferential location to facilitate cooperation with 
plates 26 and 29. Tool 10 is further brought into operative condition by 
placing lower open end 24 of shell 20 around the lifter bars 32 which are 
then passed through perforations 38, for example, as seen in FIG. 2, are 
slightly larger than the diameter of bars 32 to facilitate free passage 
therethrough. Lower edge 22 is then lowered on machinery wall 12 and 
around bearing assembly 16 and shaft 18. Plate 29 which has force applying 
bolt 30 threaded in bore 42 is lowered over plate 26 so that bars passing 
through perforations 38 will then pass through an aligned perforation 40 
in plate 29. Nuts 44 are then threaded onto bars 32. For optimum 
effectiveness, nuts 44 are adjusted so that they will allow plate 29 to be 
in supporting relationship thereunder in a plane parallel to plate 26 so 
that turning of jack screw or force applying bolt 30 effect equally 
distributed lifting force at the underside of each nut 44 and/or to each 
lifter bar 32. 
With bearing extractor tool assembled as described, it will then be 
understood that as jack screw 30 is turned in a direction to move it 
downwardly through plate 29, pilot end 34 will seat in pilot seat portion 
34 which will prevent further downward movement of screw 30 after which 
further turning in the direction to cause downward movement of screw 30 
will then effect lifting of nuts 44 and lifter bars 32 which will then 
pull upwardly and outwardly at the enlarged lifting ends 46 with the 
spherical surfaces 48 thereof pulling outwardly against upper arcuate 
surfaces of grooves in inner and outer race members 15, 17. 
With lower edge 22 of shell 20 placed against machinery wall 14, it is seen 
that a reaction area is effected thereat as a result of pushing of screw 
30 against plate 26 and pulling thereof against nuts 44. Because lower 
edge 22 of shell extends over a relatively wide area, the reaction force 
will be distributed to provide a more stable pulling system and minimize 
buckling. Moreover, with the disclosed tool, no damage would normally be 
inflicted on shaft 18. 
Additional advantages of the present invention are derived from the 
presence of windows 25 which provide both visual access to observe proper 
operation and physical access to facilitate manual adjustments such as 
insertion of bars 32 through selected perforations in plate 26 and degree 
of rotation of bars 32 to effect lifting condition. 
While pilot end 34 is illustrated as being pointed, it may be within the 
contemplation of this invention that it be flat or rounded. It is also 
within the contemplation of this invention that nuts 44 may be secured to 
plate 26 or that they be replaced by threading perforations 40, 40',40" 
which will then effect lifting of bars 32 by the respective threads 
thereof. 
Where a larger bearing assembly than 16 is to be extracted, bars 32 would 
according to the teaching of the present invention be inserted through 
perforations 38' or 38" and 40' or 40" as the case would demand. 
Use of lifter rods 32" in place of lifter rod 32 may be desired for 
example, in situations where the bearing race that is to be pulled is not 
formed with sufficient depth to receive the offset portion of lifting end 
46 of rod 32. Lifter rod 32", formed with the centrally formed end 46" 
without offset, has the advantage that it may be placed into operative 
condition by rotating rod 32" 90.degree. in either clockwise or 
counter-clockwise direction in contrast to rod 32 which must be rotated in 
only one direction once it has assumed a given position with respect to 
the bearing element that is to be pulled. 
Lifter rods 32' with slots 33' parallel to flat surfaces 50' provide at 
least two advantages over other forms of such rods. One advantage of rod 
32' is that it permits insertion of a screwdriver blade into slot 33' to 
facilitate rotation of rod 32' in the event that entry of spherical 
surface 48' into a bearing race is difficult due to comparative 
differences in size or misalignment of parts. A further advantage of the 
use of rods 32' resides in the fact that each slot 33' is formed so that 
it is parallel to flat surfaces 50' on opposite sides of spherical 
portions 48' of lifting end 46', so that such slots 33' offer tell-tale 
indication whether or not the spherical surfaces are positioned in lifting 
position. In this regard with bolt 30' centrally located with respect to 
the lifter rods 32' as seen in FIG. 7, it is clear that in the case of rod 
32' in the upper right location of the arrangement slot 33' is not 
radially directed toward bolt 30' so that spherical surface 48' is not in 
its lifting position. On the other hand, slots 33' of lifter rods 32' in 
the lower location and in the upper left location of the arrangement in 
FIG. 7 are clearly radially directed toward bolt 30' at the center of the 
arrangement, so that at a glance of slots 33' one can readily ascertain 
that spherical surfaces 48' are in position in the bearing race to lift 
the latter. 
It will be obvious to those skilled in the art that various changes may be 
made without departing from the scope of the invention and the invention 
is not to be considered limited to what is shown in the drawings and 
described in the specification.