Sealing assembly with rotatable collar

A high pressure sealing assembly for a device having a rotatable shaft. The assembly includes a stationary seal member associated with the device which has an opening generally conforming to the rotatable shaft, a rotatable seal member adapted to be mounted on the rotatable shaft to engage and cooperate with the stationary seal member, and a rotatable seal collar adapted to be mounted on the rotatable shaft to engage and cooperate with the rotatable seal member. With this arrangement, the rotatable seal collar cooperates with the rotatable shaft to maintain the rotatable seal member in engagement with the stationary seal member.

BACKGROUND OF THE INVENTION 
The present invention is generally related to shaft seals and, more 
particularly, to a sealing assembly for rotatable shafts. Specifically, 
the present invention is directed to maintaining a rotatable seal member 
in engagement with a stationary seal member by utilizing a rotatable seal 
collar. In various types of machinery, it is continuously a problem to 
seal the opening through which a rotatable shaft protrudes. The problem is 
manifested in the difficulty of preventing leakage or loss of pressure or 
loss of vacuum while at the same time avoiding undue shaft friction. The 
shaft friction can generate heat, cause loss of power, and even damage the 
machinery. One method of effecting a seal at a joint between a stationary 
element and a rotatable shaft has been through the use of packing, 
stuffing, or the like. However, packing or stuffing causes considerable 
friction on the shaft. Another method of effecting a seal has been to 
utilize O-rings. However, O-rings have presented a problem due to the 
difficulty of providing a proper material to accommodate the wear thereon 
when utilized with shafts that operate at high speed. The shaft seals have 
also for the most part required the machinery to be stripped or dismantled 
for replacement purposes. The necessity for stripping or dismantling the 
machinery is most undesireable particularly where the machinery being 
sealed is large and heavy. Moreover, in order to replace conventional 
mechanical seals, the machinery must often times be shut down for 
prolonged periods of time resulting in enormous losses in productivity. 
As a result, it has been recognized as desirable to provide the parts of a 
mechanical seal which are subject to wear in split fashion so that they 
can be easily mounted and later disassembled for repair or replacement 
purposes. This was successfully accomplished in my earlier U.S. Pat. No. 
4,215,870 issued on Aug. 5, 1980, and in my earlier co-pending patent 
application U.S. Ser. No. 363,375 filed on Mar. 29, 1982, and seals 
manufactured according to my patent and patent application have been 
installed and proven to be highly effective not only in terms of their 
sealing capabilities but also in terms of their drastic reduction in down 
time of expensive machinery used in costly processes. With the features of 
the inventions of my earlier patent and patent application, a split-type 
seal has been provided which can be easily assembled and disassembled 
relative to machinery without interferring with the positioning or 
mounting of the stationary element and the rotatable shaft associated with 
it. 
With attempts prior to my earlier patent and patent application to provide 
a split-type seal, it had been a problem to maintain a complete seal at 
all times completely about the rotatable shaft. During operation, the 
seals could easily become worn or deteriorated and the wear and 
deterioration could be non-uniform circumferentially about the shaft 
because of a number of reasons such as misalignment of the shaft with 
respect to the machinery with which it is used, or due to other factors. 
However, I was able to provide a sealing assembly which overcame the 
problem of non-uniform wearing or deterioration of the seal parts. 
As set forth in my earlier co-pending patent application U.S. Ser. No. 
363,375, I later became aware of still additional problems requiring a 
solution. For instance, sealing assemblies are often times needed in 
emergency situations. This is particularly true in applications which 
advantageously utilize the rotatable shaft seal disclosed and claimed in 
my earlier U.S. Pat. No. 4,215,870 where a seal is quickly needed on 
machinery used, for instance, in dangerous manufacturing process such as 
the grinding of caustic chemicals and the like where time is of the 
essence and the seal must be made available in the field on extremely 
short notice. However, the shafts of such machinery very significantly in 
size. Since time is of the essence in these applications, and it is not 
feasible to custom order a split seal from the manufacture, field service 
personnel have been required to stock a large variety of seals in order to 
be able to service a customer on a timely basis. 
In my earlier patent application, I successfully overcame these problems 
with a unique sealing assembly, kit and method for rotatable shafts. This 
was done by providing a separate inserted adapted to be mounted in an 
insert-receiving opening in the stationary seal member wherein a 
shaft-receiving opening in the insert is initially dimensioned so as to be 
smaller than a rotatable shaft and is thereafter adapted to be enlarged in 
the field before use so as to generally conform to the rotatable shaft. 
With this arrangement, the sealing assembly is uniquely suited to be 
selectively supplied in kit form. 
Despite the significant advances offered by my earlier patent and patent 
application, I have become aware of still other problems with shaft seals. 
In particular, and in high pressure environments, there can be a tendency 
for leakage resulting from a slight separation of the rotatable seal 
member from the stationary seal member since fluid under pressure has a 
tendency to overcome the frictional grip of the rotatable seal member on 
the rotatable shaft to thereby cause the rotatable seal member to slip on 
the shaft. While leakage is undesirable in any situation, it is entirely 
unacceptable in numerous applications where dangerous materials are 
involved. 
The present invention is directed to solving the above and other problems 
while enhancing the effectiveness and versitility of the seals described 
in my earlier U.S. Pat. No. 4,215,870 and co-pending patent application 
U.S. Ser. No. 363,375. 
SUMMARY OF THE INVENTION 
Accordingly, it is a principal object of the present invention to provide a 
high pressure sealing assembly for a device having a rotatable shaft and, 
more particularly, an assembly adapted to maintain a rotatable seal member 
in engagement with a stationary seal member by utilizing a rotatable seal 
collar. 
In the exemplary embodiment, a high pressure sealing assembly for a device 
having a rotatable shaft is provided. The assembly includes a stationary 
seal member associated with the device which has an opening generally 
conforming to the rotatable shaft, a rotatable seal member adapted to be 
mounted on the rotatable shaft to engage and cooperate with the stationary 
seal member, and a rotatable seal collar adapted to be mounted on the 
rotatable shaft to engage and cooperate with the rotatable seal member. 
With this arrangement, the rotatable seal collar cooperates with the 
rotatable shaft to maintain the rotatable seal member in engagement with 
the stationary seal member. 
Preferably, the rotatable seal collar is split along a diameter and through 
a shaft-receiving opening so as to have two substantially identical collar 
portions. The rotatable seal collar includes means for securing the collar 
portions together and the shaft-receiving opening generally conforms to 
the rotatable shaft and is no larger than the rotatable shaft, the 
securing means thereby causing the collar portions to grip the rotatable 
shaft. Moreover, the shaft-receiving opening is defined by a 
shaft-conforming surface advantageously having means for resisting 
movement along the rotatable shaft. 
Specifically, the movement resisting means includes a plurality of 
circumferentially extending teeth formed in the shaft-conforming surface. 
The teeth are preferably each definded by a radially extending face and an 
angularly disposed face, the angularly disposed face extending toward the 
rotatable shaft in a direction away from the rotatable seal member, and 
extending inwardly to form a circumferential edge with a next adjacent 
radially extending face. Advantageously, the circumferential edges have a 
radial dimension slightly less than the radical dimension of the rotatable 
shaft. In addition, the movement resisting means advantageously includes a 
plurality of axially extending grooves formed in the shaft-conforming 
surface. The grooves are each defined by a pair of angularly disposed 
surfaces extending along the rotatable shaft in an axial direction, the 
angularly disposed surfaces each extending inwardly to form an axial edge 
with the next adjacent angularly disposed surface. With this arrangement, 
the axial edges preferably have a radial dimension slightly less than the 
radial dimension of the rotatable shaft. 
Still other features of the invention include the rotatable seal collar 
having a circumferential face adapted to be disposed in confronting 
relation to the rotatable seal member. Advantageously, the circumferential 
face is provided with spacer means such as spherical locater buttons, 
adapted to be disposed in engagement with the rotatable seal member. In a 
preferred embodiment, a plurality of spherical locator buttons are 
provided in a radially disposed fashion about the circumferential face.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to the drawings, and first to FIG. 1, the reference numeral 10 
designates generally a rotatable seal collar for a sealing assembly having 
rotatable seal means in engagement with stationary seal means. The 
rotatable seal collar 10 includes a collar body 12 having a 
shaft-receiving opening 14 therein generally conforming to a rotatable 
shaft passing through the stationary seal means and the rotatable seal 
means. The collar body 12 is adapted to engage and cooperate with the 
rotatable seal means. The rotatable seal collar 10 also includes means for 
securing the collar body 12 to the rotatable shaft so as to maintain the 
rotatable seal means in engagement with the stationary seal means. As will 
be appreciated hereinafter, the securing means causes the collar body to 
move with the rotatable shaft while resisting movement along the rotatable 
shaft. 
Referring now to FIG. 3, the rotatable seal collar 10 is particularly 
adapted for use in a high pressure sealing assembly 16 for a device having 
a rotatable shaft 18. The assembly 16 then includes stationary seal means 
20 associated with the device and having an opening 22 generally 
conforming to the rotatable shaft 18, rotatable seal means 24 adapted to 
be mounted on the rotatable shaft 18 to engage and cooperate with the 
stationary seal means 20, and the rotatable seal collar 10 which is 
adapted to be mounted on the rotatable shaft 18 to engage and cooperate 
with the rotatable seal means 24. With this arrangement, the rotatable 
seal collar 10 cooperates with the rotatable shaft 18 to maintain the 
rotatable seal means 24 in engagement with the stationary seal means 20. 
As shown in FIG. 1, the rotatable seal collar 10 is split through the 
shaft-receiving opening 14 (as at 26), preferably along a diameter, to as 
to include two substantially identical collar portions 12a and 12b. It 
will also be seen that the rotatable seal collar 10 includes means for 
securing the collar portions 12a and 12b together, such as the bolts 28, 
which also comprise a portion of the means for securing the collar body 12 
to the rotatable shaft 18, as previously described. As will be 
appreciated, the shaft-receiving opening 14 is dimensioned no larger than 
the rotatable shaft 18, and the bolts 28 not only secure the collar 
portions 12a and 12b together, but also cause the collar portions 12a and 
12b to grip the rotatable shaft 18. 
As suggested above, the shaft-receiving opening 14 is defined, at least in 
part, by a shaft-conforming surface 30 having means for resisting movement 
along the rotatable shaft 18 in an axial direction, such as a plurality of 
circumferentially extending teeth 32 (see FIG. 5). The circumferentially 
extending teeth 32, which are formed in the shaft-conforming surface 30, 
are each defined by a radially extending face 32a and an angularly 
disposed face 32b extending toward the rotatable shaft 18 in a direction 
away from the rotatable seal means 24, the annularly disposed faces 32b 
each extending inwardly to form a circumferential edge 32c with a next 
adjacent radially extending face 32a such that diametrically opposed edges 
32c have a diameter slightly less than the diameter of the rotatable shaft 
18. Additionally, in a preferred embodiment, the angularly disposed faces 
32b each extend at an angle to the next adjacent radially extending face 
32a of approximately 45.degree. and the circumferential edges 32c each 
have a radial dimension on the order of approximately 0.002 to 0.003 
inches less than the radical dimension of the rotatable shaft 18. 
Referring now to FIG. 4, the shaft-conforming surface 30 may include means 
for resisting movement along the rotatable shaft 18 in an axial direction 
such as a plurality of axially extending grooves 34. The axially extending 
grooves 34 are each defined by a pair of oppositely angularly disposed 
surfaces 34a and 34b extending along the rotatable shaft in an axial 
direction, the angularly disposed surfaces 34a and 34b each extending 
inwardly to form an axial edge 34c with a next adjacent angularly disposed 
surface having a radial dimension slightly less than the radial dimension 
of the rotatable shaft 18. Specifically, in a preferred embodiment, the 
angularly disposed surfaces 34a and 34b intersect at an angle of 
approximately 90.degree. and the axial edges 34c each have a radial 
dimension on the order of approximately 0.002 to 0.003 inches less than 
the radial dimension of the rotatable shaft 18. 
As will be appreciated from FIG. 2, in a preferred embodiment, the 
rotatable seal collar 10 includes both a plurality of circumferentially 
extending teeth 32 and a plurality of axially extending grooves 34. While 
it is possible for the rotatable seal collar 10 to operate with either a 
smooth surface (with a frictional interference fit), a surface having 
circumferentially extending teeth, or a surface having axially extending 
grooves, it is believed most advantageous for the shaft-conforming surface 
30 to include not only a plurality of circumferentially extending teeth 
32, but also a plurality of axially extending grooves 34. With this 
arrangement, as schematically illustrated in FIG. 2, the intersection of 
the circumferentially extending teeth 32 with the axially extending 
grooves 34 form a plurality of radially inwardly and rearwardly directed 
points 36. 
As will be appreciated, the points 36 are adapted to bite into the 
rotatable shaft 18 inasmuch as diametrically opposed points 36 will be 
separated by a diameter slightly less than the diameter of the rotatable 
shaft 18, i.e., on the order of approximately 0.002 to 0.003 inches less. 
When the bolts 28 are tightened to secure the collar portions 12a and 12b 
together about the rotatable shaft 18, the radially inwardly directed 
points 36 will bite into the rotatable shaft 18 and will effectively 
prevent the rotatable seal collar 10 from slipping axially along the 
rotatable shaft 18. 
Referring to FIGS. 1 through 3, the rotatable seal collar 10 includes a 
circumferential face 38 adapted to be disposed in confronting relation to 
the rotatable seal means 24. The circumferential face 38 is advantageously 
provided with spacer means adapted to be disposed in engagement with the 
rotatable seal means 24 (see FIG. 3). Preferably, the spacer means 
comprises a plurality of spherical locator buttons 40 radially disposed 
about the circumferential face 38. 
Still referring to FIGS. 1 through 3, the rotatable seal collar 10 may 
advantageously include a plurality of genrally U-shaped notches 42. The 
notches 42 are provided in the embodiment illustrated to receive the 
projecting portions of the spring plunger assemblies 44 in the rotatable 
seal means 24. As can be seen in FIG. 3, the spring plunger assemblies 44 
can be adjusted through the notches 42 without removing the rotatable seal 
collar 10 from the rotatable shaft 18. 
While the notches 42 have been illustrated, it will be appreciated that 
they are not essential. It is contemplated, for instance, that the 
rotatable seal collar 10 will have much wider ranging applicability than 
for use only with my earlier U.S. Pat. No. 4,215,870 and my earlier 
co-pending patent application U.S. Ser. No. 363,375, and, while the 
rotatable seal collar 10 is particularly adapted for use in high pressure 
sealing assemblies, it may be used in any sealing assembly where its 
benefits could be of value. Accordingly, while I have illustrated the 
rotatable seal collar 10 in use with my earlier invention, it will be 
appreciated that the advantages to be derived from using the rotatable 
seal collar 10 may be enjoyed by anyone having a seal on a shaft. 
While in the foregoing specification a detailed description of the 
invention has been set forth for purposes of illustration, it will be 
appreciated by those skilled in the art that the details herein given may 
be varied without departing from the spirit and scope of the invention.