Guide sleeve with seal, guide post and ball bearing assembly

A guide post, guide sleeve, and ball bearing assembly especially for a die set has a leak proof seal contained within one end of the guide sleeve for slidably sealing the interface between the guide post and guide sleeve and slidingly cleaning the surface of the guide post during relative reciprocal movements of the guide post and guide sleeve. The assembly maintains optimal lubrication of the ball bearing assembly while providing a cleaner, more frictionless configuration.

FIELD OF THE INVENTION 
The present invention generally relates to a die set with a guide sleeve 
having a seal, guide post and ball bearing assembly for maintaining the 
opposite die shoes of the die set in alignment during relative reciprocal 
movements. 
BACKGROUND OF THE INVENTION 
Bearing assemblies are well known. An example of a ball bearing assembly is 
disclosed in U.S. Pat. No. 4,664,534 dated May 12, 1987, and issued to the 
present inventor. The ball bearings within the ball bearing assembly must 
be lubricated to reduce the friction within the system to a minimum. The 
open ended guide sleeve of the U.S. Pat. No. 4,664,534 bearing assembly 
limits how and where the lubrication can be maintained in the system. 
Typically, the guide sleeve was maintained in a lower die shoe with a seal 
at the bottom thereby providing a reservoir for lubricating fluid, such as 
oil, to lubricate the ball bearings. In such a configuration, there were 
limitations on the amount of lubrication provided to the ball bearing 
cage. In the typical configuration, the lubricating fluid reservoir was 
only at the bottom of the guide sleeve. Therefore, the top portion of the 
ball bearing cage, which engages the guide post more often than the lower 
portion, did not receive optimal lubrication throughout its stroke. 
Further, the open ended guide sleeve reservoir requires a spatial 
orientation including horizontal die shoes with the guide sleeve set 
vertically within the lower shoe. Any other orientation would result in 
the lubricating fluid leaking out of the reservoir, defeating the intended 
purpose and potentially interfering with the die casting, stamping or 
injection molding. Additionally, any debris or dirt in the system 
potentially could collect on the ball bearing assembly or the guide post 
thereby causing additional friction and wear leading to untimely loss of 
precision of the tooling and accuracy in the manufactured component. 
Previously with guide post, guide sleeve and ball bearing assemblies there 
was not known any means for positively assuring an adequate lubrication of 
the ball bearing cage and maintaining a relatively dirt free environment 
for the ball bearings to act upon the guide post within the guide sleeve. 
SUMMARY OF THE INVENTION 
An important feature of the present invention is to provide adequate 
lubrication to the ball bearing cage assembly. The present invention 
maintains a superior lubricating system for the ball bearing assembly by 
having a sealing member fixedly attached to one end of the guide sleeve. 
The sealing member provides a means for maintaining a lubricating fluid 
reservoir within the entire guide sleeve that receives the entire ball 
bearing cage assembly inside an internal bore. The sealing member is 
placed between the interface between the guide sleeve and guide post 
providing a leak proof barrier to maintain lubricating fluid inside the 
guide sleeve. In this manner, the lubricating fluid is available to 
constantly lubricate the entire ball bearing cage. 
An additional advantage of the inventive guide sleeve seal is that it 
effectively removes limits on the guide sleeve's spatial orientation 
relative to the die set. For example, previously guide sleeves had to be 
placed vertically within a lower horizontal die shoe so that any 
lubricating fluid maintained in a reservoir at the bottom of the guide 
sleeve would not leak out during a typical die casting operation. With the 
inventive sealing member attached to a guide sleeve, it is possible to 
maintain a guide sleeve on an upper horizontal die shoe or a vertical die 
shoe or one oriented at any angle. In this manner, greater versatility is 
available for configuring die sets allowing full lubrication of the ball 
bearing cage without allowing any of the lubricating fluid to leak into 
the system outside of the guide sleeve. Moreover, affixing the guide 
sleeve to an upper die shoe concentrates the lubricating fluid where it is 
needed most; at the points where the ball bearing assembly engages the 
guide post throughout a die casting operation. 
A further advantage of the present invention is that it provides a means 
for cleaning the guide post during a die casting, metal stamping or 
injection molding operation. The sealing member travels longitudinally 
along the surface of the guide post during the die shoe reciprocal 
movements effectively cleaning the guide post. The seal provides a 
sweeping, cleaning action as it slides along the guide post. In this 
manner, any debris or dirt that collects on the guide post during a die 
casting operation is pushed away by the sealing member preventing it from 
entering the guide sleeve, collecting on the ball bearings or 
contaminating the lubricating fluid. Therefore, the inventive guide sleeve 
seal provides a means for maintaining cleaner lubrication of the ball 
bearing cage assembly which, effectively reduces the amount of friction 
between the guide post, guide sleeve, and the interposed ball bearings and 
lengthens life of original tooling specification. 
These and other features and objects of the present invention will be seen 
in the following specification and claims in conjunction with the appended 
drawings, of which the following is a brief description.

DETAILED DESCRIPTION OF THE INVENTION 
Referring to FIG. 1, there is shown a guide sleeve, guide post and ball 
bearing assembly incorporating the inventive guide sleeve sealing member. 
The guide post 20 is shown affixed to a lower die shoe 22 press fitted in 
an inner aperture 24 in the lower die shoe. 
Guide sleeve 26 is shown affixed to an upper die shoe 28 within an aperture 
30 and axially aligned such that it slidably receives guide post 20 during 
relative reciprocal movements between die shoes 22 and 28. Guide sleeve 26 
has an internal coaxial bore 32 and a plug 34 maintained at the end of the 
guide sleeve affixed to the die shoe 28. At the opposite end of the guide 
sleeve, there is a sealing member 36 which slidably seals the interface 
between the free end 37 of guide sleeve 26 and guide post 20. 
Sealing member 36 is fixedly maintained within the free end 37 of guide 
sleeve 26. Free end 37 preferably has a tapered, conical exterior that is 
narrowest near a terminal point on guide sleeve 26. The interior of free 
end 37 is preferably of a smaller radius than interior bore 32. The inner 
peripheral surface of free end 37 preferably has a nominal radius that is 
only slightly larger than the outside radius of guide post 20 such that 
guide sleeve 26 slidably receives guide post 20. Free end 37 preferably 
contains a notch 38 extending radially outward and having a radius that is 
slightly larger than the nominal radius of free end 37. Notch 38 
preferably has a constant radius for a portion of its longitudinal length 
beginning at a reaction surface 39a defined at a most internal end of the 
notch and ending at a second reaction surface 39b. The radial length of 
the second, more external reaction surface 39b is approximately half the 
length of the most internal reaction surface 39a, which is equal to the 
radius of the notch at its most internal end minus the nominal radius of 
free end 37. Adjacent the second reaction surface, the radius of notch 38 
begins to steadily decrease until a point adjacent a terminal point on 
guide sleeve 26 where the radius of notch 38 is approximately equal to the 
nominal radius of free end 37. Notch 38, therefore has a tapered conical 
portion that is widest at its most internal end and extends longitudinally 
outward from second reaction surface 39b to a point adjacent a terminal 
point on guide sleeve 26. 
The shape of notch 38, therefore, defines a pair of axially opposing 
reaction surfaces 39a and 39b that bear against sealing member 36 such 
that sealing member 36 remains stationary relative to guide sleeve 26 
during reciprocal movements between guide sleeve 26 and guide post 20. In 
this manner, free end 37 of guide sleeve 26 is shaped to securely contain 
a sealing means 36 such as a correspondingly shaped rubber coaxial ring. 
The ball bearing cage 40 is of cylindrical form and is maintained within 
the central bore 32 of the guide sleeve and adjustably receives the guide 
post 20. Cage 40 is maintained in central bore 32 by known retention 
means, such as for example the retention means disclosed in U.S. Pat. No. 
4,665,534 which is incorporated herein by reference. Ball bearing cage 40 
maintains a plurality of ball bearings 42 in a series of longitudinally 
spaced circles of radially bored holes. The ball bearings 42 are 
circularly arranged and project inwardly and outwardly respectively, of 
the ball bearing cage 40 and are engageable with guide post 20 and with 
the internal coaxial bore 32 of guide sleeve 26. 
A reservoir 43 for lubricating fluid 44 is maintained within internal bore 
32 between the end 45 of the interior of the guide sleeve 26 and the plug 
34 by seal 36. In the disclosed embodiment, oil is supplied to the 
interior of guide sleeve 26 through openings 50 in sleeve 26. Lube filler 
openings 52 are provided in the die shoe 28 and intersect the opening 50. 
Therefore, the ball bearing cage 40 is maintained within a generally 
enclosed environment containing lubricating fluid. Moreover, the inventive 
configuration allows for the lubricating fluid to be maintained where it 
is required most. In the illustrated embodiment, the ball bearing cage 40 
engages the guide post 20 near the lower end of the guide sleeve. With the 
inventive guide sleeve seal configuration, it is possible to concentrate 
lubricating fluid at the lower end of the guide sleeve thereby lubricating 
the ball bearings at the point where they engage the guide post throughout 
its stroke which may reach 2500 strokes per minute. The inventive 
configuration facilitates cooler operation under such high speed 
conditions, and therefore, adds additional life to original tolerance 
specifications. 
Although FIG. 1 illustrates guide sleeve 26 above guide post 20, the 
configuration could be reversed such that guide sleeve 26 is below guide 
post 20. In this latter configuration, sleeve 26 is preferably modified to 
include a cap to prevent lubrication loss or migration. 
FIG. 2, wherein like numerals refer to like parts of the guide post, guide 
sleeve assemblies, shows an example of the prior art wherein the oil 
reservoir 46 is maintained at a lowest end of the guide sleeve closest to 
the die shoe 22 and furthest from the point where the ball bearing cage 
assembly adjustably receives the guide post. Therefore, optimal 
lubrication of the ball bearings is not maintained without the inventive 
guide sleeve seal configuration. 
Referring again now to FIG. 1, as guide post 20 and guide sleeve 26 move 
reciprocally, the sealing member 36 slidingly moves longitudinally along 
guide post 20 effectively performing a cleaning action along the edge of 
the guide post. Therefore, sealing member 36 prevents any dirt, dust or 
debris which may have collected on guide post 20 from entering into the 
lubricating fluid reservoir 43. As can be seen in FIG. 2, in the prior 
art, a gap exists between guide sleeve 26 and guide post 20 such that any 
debris or dirt collecting on guide post 20 could contaminate the 
lubricating fluid 48. Therefore, the inventive guide sleeve seal provides 
a more effective lubricating fluid reservoir, resulting in a better, more 
frictionless environment within a die set. In the prior art, any debris or 
dirt collecting on a ball bearing or guide post or within the lubricating 
fluid reservoir would increase the amount of friction during reciprocal 
movement of the guide post and guide sleeve with the interposed bill 
bearing cage assembly and could scar the post creating more wear on the 
system. 
The inventive guide sleeve seal is adaptable for use with any guide sleeve, 
guide post and ball bearing assembly for a die set including those where 
the ball bearing assembly is not rotatably mounted and those where the 
ball bearing assembly is rotatably mounted, such as in U.S. Pat. No. 
4,664,534, previously described. 
It will be apparent to those skilled in the art that the foregoing 
disclosure is exemplary in nature rather than limiting, the invention 
being limited only by the appended claims.