Two piece inner tube

In the formation of an elastomeric tube or the like on a toroidal core, elastomeric material is applied to the core generally along one side of the core, and force-applying means are utilized to press annular portions of the so-deposited elastomeric material onto the core. Cutting means are also included for cutting away elastomeric material not deposited on the core. The core and elastomeric material deposited thereon are then turned over and the operation is repeated, whereby elastomeric tube means or the like are provided on the toroidal core.

BACKGROUND OF THE INVENTION 
This invention relates to apparatus and method for applying elastomeric 
material to a core, and more particularly, to such apparatus and method in 
which elastomeric material is applied to opposite sides of a toroidal 
core. 
U.S. Pat. No. 3,606,921 issued to Grawey (assigned to the assignee of this 
application) discloses a novel, oval pneumatic tube-tire. Such tire is 
generally constructed by forming an oval, torodial tube member of 
elastomeric material on a disintegrable core, winding inextensible 
filament about the toroidal tube member, and applying further layers of 
material to form the final tube-tire as illustrated therein. The core is 
then disintegrated and removed from within the tube-tire. 
Of particular importance in the manufacture of such tire as disclosed in 
that patent is the proper formation of the oval, toroidal tube member on 
the disintegrable core, in preparation for the wrapping of filament 
material thereabout. Obviously, the method and the apparatus for 
practicing such method should be as simple and effective as possible, 
especially considering that the core which is used may be extremely heavy 
and large. 
While the method of forming the tube by means of wrapping tape about the 
core has proved to be relatively effective, it will be understood that 
such wrapping is a relatively time-consuming operation, and must be done 
with extreme care so as to prepare a proper surface for the wrapping of 
wire thereon. Even if such operation is undertaken with great care, the 
lap marks which result from the overlapping of such tape material being 
wrapped are a hindrance to the proper wrapping of the wire thereon, it 
being evident that the presentation of a smooth tube surface to the wire 
to be wrapped thereon is preferable. 
It will also be understood that in certain applications, an annular strip 
of elastomeric material is to be applied to each side of the core, 
actually being applied to elastomeric material already applied to the 
core, and forming a part of the oval, toroidal tube member. While it is 
understood that such side-wall portions of the toroidal tube member can 
also be applied by hand, it will be understood that such hand application 
is a relatively time-consuming operation, and must be done with extreme 
care so as to properly position such added elastomeric material. 
Of interest in this area are U.S. Pat. Nos. 3,608,016 to Loberod et al, 
2,953,814 to Mumford, 1,856,694 to De Correvont, 3,159,695 to Behringer, 
2,830,818 to Otto, and 3,342,914 to Edwards. However, it will be seen that 
none of these patents are concerned with application of elastomeric 
material to a toroidal core. For purposes of the claims in this case, the 
term "core" is to be understood to mean not only the actual base core of, 
for example, sand, but also any elastomeric material which has been 
deposited on such base core. That is, the "core" acted upon in the method 
and by the apparatus of the claims is to be understood to include not only 
the base core, but also any elastomeric material already applied to such 
base core at that point in operation. 
SUMMARY OF THE INVENTION 
It is accordingly an object of this invention to provide method and 
apparatus for forming an elastomeric tube or a portion of a tube on a core 
which results in the tube or tube portion formed thereon having a 
relatively smooth outer surface. 
It is a further object of this invention to provide method and apparatus 
which, while fulfilling the above object, are capable of being practiced 
and used to effectively and properly form such elastomeric tube or tube 
portion, meanwhile being quite simple in design and rapid and effective in 
use. 
It is a still further object of this invention to provide a tube structure 
which is extremely efficient in design and effective in use, and which may 
preferably be formed through the practice of such method and apparatus. 
Broadly stated, disclosed herein is a method of forming a portion of a tube 
on a toroidal core comprising the steps of positioning a sheet of 
elastomeric material adjacent the toroidal core along one side thereof, 
depositing elastomeric material of the sheet thereof onto the toroidal 
core along a continuous path thereof, and applying force to an annular 
portion of elastomeric material associated with the core to urge the 
annular portion of elastomeric material against the core, independent of 
any force to initially deposit elastomeric material of the sheet onto the 
core along the continuous path thereof. 
Broadly stated, the invention comprises apparatus for forming a portion of 
a tube on a toroidal core from elastomeric sheet material. Such apparatus 
comprises frame means, support means operatively associated with the frame 
means for supporting a toroidal core, and means operatively associated 
with the frame means for positioning and supporting a sheet of elastomeric 
material adjacent a so-supported core along one side of the so-supported 
core. Further included are means for depositing elastomeric material of 
the sheet thereof onto the so-supported toroidal core along a continuous 
path thereof. Further included are means for selectively applying force to 
an annular portion of the elastomeric material associated with the core to 
urge an annular portion of elastomeric material against the so-supported 
core. 
Broadly stated, the invention also comprises a toroidal tube structure 
comprising a first tube portion defining a side portion and inner and 
outer peripheral portions, and a second tube portion defining a side 
portion and inner and outer peripheral portions overlapping to an extent 
the respective inner and outer peripheral portions of the first tube 
portion.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Shown in FIG. 1 is a toroidal sand core 10 which rests on support means 12, 
which may be, for example, a series of spaced blocks with individual 
concave upper surfaces to conform to the core shape, or a circular member 
which supports the core for a full 360.degree.. Support means 12 attach to 
a circular plate 14 supported on a fixture 15 that is connected to a power 
mechanism, the purpose of which is to raise and lower core 10, support 
means 12, and plate 14. 
With the positioning of elements as shown in FIGS. 1 and 3, an annular ring 
16 is disposed about the outer periphery of the core 10 and spaced 
therefrom. Such annular ring 16 is fixed to a circular base plate 18. The 
plate 14 rests on an annular seal 20 fixed to a circular base plate 18 
along the inner periphery thereof. A ring plate 22 has its outer periphery 
fixed to and in contact with the annular ring 16 and extends inwardly 
thereof. A disc 24 is fixed relative to and supported above the plate 14 
by means of support rods 25. The ring plate 22 and disc 24 define a 
plurality of apertures 26 therethrough as shown. With the core 10 and 
plate so positioned as shown, the ring plate 22 and disc 24 lie generally 
in the mid-circumferential plane of the toroidal core 10. With such 
positioning, the outer periphery of the core 10 is in close proximity to 
the inner periphery of the ring plate 22, and the outer periphery of the 
disc 24 is in close proximity to the inner periphery of the core 10. 
In preparing to form a portion of a tube on the core 10, a length of 
uncured elastomeric sheet material 28, such as rubber, is pulled from a 
roll 30 and positioned along a flange portion 32 defined by the annular 
ring 16 in a manner to close and seal the opening of a chamber 33 now 
defined by the sheet member 28, the annular ring 16, the base plate 18, 
the seal 20, and the plate 14. The flange portion 32 of the annular ring 
16 positions and supports such sheet of elastomeric material 28. 
The sheet portion so supported is positioned generally along and parallel 
to the mid-circumferential plane of the core 10. As rubber is pulled from 
the roll 30, the separator sheet 34 separating the layers of rubber on the 
roll 30 is removed and wound on a take-up reel 36. The reel 36 could to 
its advantage be spring-loaded or motor powered through the use of a 
slipping clutch arrangement to keep the sheet 34 taut as it comes off the 
roll 30, but without exerting sufficient force to break the sheet 34. 
At this point, a vacuum is drawn through a conduit 38, which communicates 
with the chamber 33, to apply a pressure differential to the sheet 28. 
That is, a vacuum is applied to the side of the sheet 28 facing the core 
10, and the side of the sheet 28 facing away from the core 10 is exposed 
to atmospheric pressure. Through such pressure differential, the sheet 28, 
adhered to the flange portion 32 defined by annular ring 16, is stretched 
and drawn downwardly so that a portion of the sheet 28 is deposited on the 
core 10. The disc 24 and ring plate 22 limit the area of the core 10 on 
which the sheet 28 is deposited, so that the deposited material extends 
continuously along the inner and outer peripheries of the core 10 a small 
amount past the mid-circumferential plane of the core 10. 
The core 10 may with advantage be of porous material, so that the vacuum is 
applied to the sheet material 28 deposited on the core 10 through the 
porous core, pulling the sheet material 28 into tight contact with the 
core 10. 
While the sheet material is held by the vacuum in the position shown, 
cutter 40 is moved into position by a control mechanism. After cutter 40, 
including inner and outer cutting members 42,44, is properly positioned 
above the core 10, it is lowered to cut the portions of the sheet 28 not 
disposed on the core 10 away from the portion deposited on the core 10. 
After the cutter 40 is removed from the core 10, the severed portions of 
sheet material may be removed, leaving only the deposited and formed 
portion. 
After forming of such portion, the core 10 is elevated to the position 
shown in FIG. 5 and a hoist can be moved into position to permit the core 
10 to be lifted and inverted to position the uncovered portion of the core 
10 upwardly. The power mechanism can then be used to lower the core 10 to 
the position shown in FIG. 3. 
Elastomeric sheet material 46 is then applied to the uncovered portion of 
the core 10 through the vacuum means in the same manner as previously 
described. A portion of the second sheet of material 46 deposited on the 
core 10 extends continuously a small amount past the mid-circumferential 
plane of the core 10 and continuously overlaps the portion already 
deposited continuously along the inner and outer peripheries of the core 
10. The material not deposited is removed as previously described. 
At this point, the overlapping of the portions result in thick sections 
which should be flowed into a smoothly blended joint with a secure bond, 
and without sharp angular edges which may be left by the cutting 
operation. To accomplish this, a stitching operation is carried out by 
apparatus 48 as shown in FIG. 5. 
A control device capable of producing vertical, horizontal and rotary 
motion is connected through a shaft 50 to a fixture arm 52. A pair of 
shafts 54,56 are pivotally supported on a fixture arm 52 through pivots. A 
stitching roller 58 is rotatably attached to the lower or free end of each 
shaft 54,56. A loading device 60 is connected between the shafts 54,56 and 
is functional to establish motion about the pivots to move rollers 58, 
either away or toward each other. Thus, rollers 58 and shafts 54,56 can be 
controlled to exert an inward force on an object positioned between the 
rollers 58, or can be moved outwardly to release the object. 
With both tube portions formed and trimmed through the cutting means 40, 
the lift mechanism can be used to elevate the plate 14, and this core 10, 
to the position shown. The control is then used to position shaft 50 at 
the center point of the core 10, and with rollers 58 positioned away from 
each other by device 60, shaft 50 and arm 52 are lowered to the position 
shown. This positioning orients arm 52 and shafts 54,56 properly with 
respect to core 10, such that the loading device 60 can be used to urge 
shafts 54,56 toward each other. 
The rollers 58 are brought into flush contact with the overlapping portions 
of the deposited sheet material with the shafts 54,56 vertical and 
parallel. The device 60 can then be adjusted to exert the desired force on 
the overlapping portions for the stitching operation and the shaft 50 
rotated to stitch the overlapping portions or seams simultaneously. This 
causes the uncured rubber at the overlapping portions to flow into a 
smoothly blended joint with a complete bond between the portions. 
Loading device 60 and the control are then actuated to release the rollers 
58 and elevate and rotate shaft 50 to remove the stitching apparatus from 
the core 10. 
After such stitching operation is accomplished, the core and tube formed 
thereon may be removed to a waiting station or to appartus for further 
application of material in, for example, the case of the tube-tire 
disclosed in U.S. Pat. No. 3,606,921 mentioned above, or to a curing mold 
if a basic tube is being fabricated. 
It will be understood, of course, that other embodiments of the invention 
are possible. For example, it will be seen that the core 10 could be 
supported with its mid-circumferential plane disposed vetically. It will 
also be understood that the cutting means for cutting the portions of 
sheets not deposited on the core could take a variety of configurations. 
Obviously, the problems created by forming the tube of overlapping 
elastomeric tape are completely avoided through this invention. 
Shown in FIGS. 6-9 is a second embodiment of apparatus 100 for forming a 
portion of a tube on a toroidal core. Such apparatus 100 includes frame 
means 102 including a base portion 104 further including upwardly 
extending legs 106, to which is fixed a body 108 including a cylindrical 
sidewall portion 110 and a lower portion 112, fixed to and within the 
cylindrical sidewall portion 110. The lower portion 112 has fixed thereto 
and extending downwardly therefrom three socket portions 114, one of which 
is best shown in FIGS. 6 and 10, and each socket portion 114 has 
associated therewith similar structure also shown most clearly in FIGS. 6 
and 10. Consequently, the detailed structure of only one of these 
assemblies will be described. 
The lower portion 112 has fixed to the lower surface thereof a plate 116, 
and the upper end of the socket portion 114 is fixed to the inner 
periphery of the plate 116. The lower portion 112 has fixed to the upper 
surface thereof a plate 118, which in turn has fixed to the upper surface 
thereof a washer 120. The plate 118 and washer 120 together define an 
annular channel 122 in which is seated a radial portion 124 of a hub 126, 
to which a sprocket 128 is fixedly secured. The inner bore 130 of the hub 
126 has threads formed therein, which engage with the outer threads of an 
elongated shaft 132, the lower extended end of which is positioned in the 
socket portion 114. FIG. 8 shows two similar shafts 134,136 which are 
associated with the lower portion 112 of the body 108 in a similar manner, 
having similar hub and sprocket assemblies associated therewith. The 
shafts 132,134,136 are positioned substantially 120.degree. apart about 
the body 108. The sprockets associated with shafts 132,134,136, are 
connected by an endless driving chain 138 (FIGS. 6 and 10), which may be 
connected in a well-known manner to a wheel 140 through a gear box, or to 
a motor through such gear box, to drive the chain 138 in one and the other 
directions to rotate the sprockets including sprocket 128 in one and the 
other directions to raise and lower the non-rotating shafts 132,134,136. 
It will thus be seen that through movement of the chain 138, the assembly 
associated with the upper ends of the shafts 132,134,136 can be 
selectively raised and lowered. 
An annular support member 142 is fixed to the respective upper ends of the 
shafts 132,134,136. Such annular support member 142 is indented in 
cross-section as best shown in FIG. 10, and the upper surface has fixed 
thereto an elastomeric portion 144 on which a toroidal core 146 is to be 
seated (for example see FIG. 21). 
A mounting structure 148 is operatively associated with the upper ends of 
the threaded shafts 132,134,136. Such mounting structure 148 includes an 
inner cylindrical mounting wall 150, an outer cylindrical mounting wall 
152, spaced apart so that the support member 142 can be disposed 
therebetween, and plate assemblies 154,156,158 extending between and fixed 
to the wall 150 and wall 152. The plate assembly 154 is actually made up 
of a plate 160 fixed to the walls 150,152 and a plate 162 fixed to plate 
160, the plates 160,162 together defining an annular channel 164 in which 
is seated a radial portion 166 of an internally threaded hub 168. Such 
internally threaded hub 168 has the threads thereof in engagement with the 
threads of the shaft 132, and the hub 168 also has fixed thereto a 
sprocket 170. It will be seen that this hub and sprocket assembly 168,170 
is rotatable relative to the mounting structure 148. 
The plate assemblies 156,158 are associated with the shafts 134,136 
respectively in a similar manner, having sprockets 172,174 and hubs 
associated therewith. 
The lower portion 112 has fixed thereto a gear box 176 (FIG. 13), in input 
shaft 178 of which may be rotated by a handle 180 (FIG. 6) or motor as is 
well-known, and the output shaft 182 of such gear box 176 connects with an 
upwardly extending shaft 184 by means of a coupling 186. The shaft 184 is 
in fact not threaded but has an elongated spline 188 formed therein. Yet 
another plate 190 interconnects and is fixed to the walls 150,152 (see 
also FIG. 8). The plate 190 includes an extended portion 192 to which is 
fixed a plate 194, and the plates 190,194 together define an annular 
channel 196 in which is seated a radial portion 198 of a hub 200. The hub 
200 has fixed thereto a sprocket 202, and the shaft 184 is disposed 
through central openings of the hub 200 and sprocket 202. A set screw 204 
is disposed through a lateral hole in the hub 200, and engages with the 
spline 188 defined by the shaft 184, so that it will be seen that the 
rotation of the shaft 184 about its longitudinal axis rotates the sprocket 
202, but with the sprocket 202, hub 200, and portion of the mounting 
structure 148 associated therewith being allowed to move along the 
longitudinal axis of the shaft 184. 
A chain tensioner 205 (FIG. 8) is mounted to the walls 150,152 as a portion 
of the mounting structure 148, and an endless chain 206 extends about the 
sprocket 202, about the sprocket 208 of the chain tensioner 205, about the 
sprocket 174, about the sprocket 170, and about the sprocket 172. It will 
be seen that rotation of the shaft 184 by means of a handwheel or motor 
rotates the sprocket 202 to in turn rotate the hub 200 and sprockets 
170,172,174 to selectively move the mounting structure 148 upwardly and 
downwardly along the non-rotating shafts 132,134,136. Guide arms 209 are 
fixed to the lower surfaces of the walls 150,152 and have guide rollers 
211 fixed to their extended ends which bear on the inner surface of the 
cylindrical sidewall portion 110 of the body 108 to properly position and 
guide the inner and outer walls 150,152 together during upward and 
downward movement thereof. 
It is to be seen that upon actuation of only chain 138, the support member 
142 and mounting structure 148 may be raised or lowered together. Upon 
actuation of only chain 206, the mounting structure 148 may be raised or 
lowered relative to the support member 142. 
The upper portion of the wall 150 has formed therein a plurality of holes 
210 (FIGS. 10 and 13), and disposed in each hole 210 is a spring 212 which 
extends above the upper surface of the wall 150. An annular knife mounting 
element 214 is positioned above the upper surface of the wall 150, and 
defines a plurality of holes 216 in which are seated the upper ends of the 
respective springs 212. The knife mounting element 214 has fixed thereto 
an annular knife element 218. The wall 150 has fixed thereto a plurality 
of guide members 220, each defining an elongated vertical slot 222 in 
which is slidably disposed a pin 224 fixed to and extending from the knife 
mounting element 218. The resilience of the spring 212 bearing on the 
knife mounting element 214 urges the knife mounting element 214 and knife 
element 218 into an upper position wherein the pins 224 contacts the 
uppermost surfaces defining the elongated vertical slot 222 (FIG. 11). 
However, it will be seen that upon application of a generally downward 
force to the knife element 218, the knife element 218 and knife mounting 
element 214 will be allowed to move downwardly relative to the wall 150 
against the resilience of springs 212 until the pins 224 contact the lower 
surfaces defining the elongated vertical slots 222 (FIG. 12). 
The upper portion of the wall 152 has associated therewith a like annular 
knife mounting element 226, which in turn has an annular knife element 228 
fixed to and extending upwardly therefrom. The upper portion of the wall 
152 and the knife mounting element 226 are associated in the same manner 
as the wall 150 and knife mounting element 214, by means of a plurality of 
springs 230 and a plurality of guide members 232 for providing that the 
knife mounting element 226 and knife element 228 may be moved relative to 
the wall 152 in a similar manner, but with the movement thereof being 
constrained by the pins and slotted guide members similar to the above. 
Fixed to the lower portion of the body 108 within the cylindrical portion 
110 is a tank 234 (FIG. 6) which includes a central tubular portion 236 
defining a central vertical bore 238 therethrough. The tank 234 may be 
completely closed off by the insertion of a cap bolt 240, or may be opened 
by removal of such cap bolt 240. A central shaft 242 is disposed through 
the tubular bore 238 and through a collar 244 fixed to the lower portion 
112. The shaft 242 defines through its lower end a plurality of bores 246, 
and a pin 248 may be disposed through an appropriate bore in the collar 
244 and one of the bores 246 in the shaft 242, to position the shaft 242 
relative to the body 108 along the longitudinal axis of the shaft 242. The 
upper end of the shaft 242 has fixed thereto a circular table portion 250, 
so that it will be seen that the vertical positioning of the circular 
table portion 250 relative to the body 108 may be chosen by means of the 
pin and bore assembly described. 
Fixed to the upper surface of the cylindrical portion 112 is an outer 
annular table portion 252. Such outer annular table portion 252 has fixed 
thereto about the outer periphery thereof a plurality of hydraulic clamp 
cylinders 254, the operation of which will be described further on. 
The table portion 252 has fixed thereto and upwardly extending therefrom 
beams 256,258,260 (FIGS. 6 and 7). A cross beam 262 interconnects the 
beams 256,258, and a beam 264 is fixed to the beam 260 and the central 
portion of beam 262. Plates 266,268 are fixed to the beam 262, and extend 
outwardly therefrom in a direction generally opposite the direction of 
extension of the beam 264 therefrom. The beam 264 has rotatably mounted 
relative thereto a hub and sprocket assembly 270,272 (FIG. 9) similar to, 
for example, the hub and sprocket assembly 126,128 rotatably mounted to 
the lower portion 112. The plates 266,268 have like hub and sprocket 
assemblies (including sprockets 280,282) rotatably mounted relative 
thereto. The hubs thereof are internally threaded, and the threads thereof 
engage with the external threads of respective elongated vertical shafts 
274,276,278. It is to be seen that rotation of the sprockets 272,280,282 
and hubs therewith moves the non-rotating shafts 274,276,278 vertically. 
An endless chain 284 is disposed about and in engagement with the sprocket 
272, the sprocket 280, the sprocket 282, a tensioning sprocket 286, and a 
drive sprocket 288 fixed to a plate 290 which is in turn fixed to the 
cross beam 262. The drive sprocket 288 may be driven by a hand crank 292 
or by motor means, as is well-known. 
An annular carriage ring 294 (FIGS. 6 and 9) is fixed to the lower extended 
end of each shaft 274,276,278, and the carriage ring 294 has fixed to the 
lower surface thereof a plurality of substantially U-shaped members 296. A 
first plurality 298 of link means 300 are pivotally mounted relative to 
the carriage ring 294, and a second plurality 302 of link means 304 are 
pivotally mounted relative to the carriage ring 294. Each of such link 
means 300 is made up of a pair of links 306 pivotally mounted to an 
extended end of a U-shaped member 296, and each of such link means 304 is 
made up of a pair of links 308 pivotally mounted to another extended end 
of the substantially U-shaped member 296 (see also FIG. 14). Each of the 
plurality of link means 300 is disposed inwardly of an associated one of 
the plurality of link means 304 toward the central axis 147 (FIGS. 21-25) 
of a toroidal 146 positioned upon the support member 142. The upper 
extended ends of each pair of associated link means 300,304 are connected 
by a hydraulic cylinder 305, so that extension of such hydraulic cylinder 
305 moves the lower extended ends of the associated link means 300,304 
together, and retraction of the cylinder 305 moves the lower extended ends 
of the associated link means 300,304 relatively apart. Biasing springs 309 
interconnect each link means 300,304 and the carriage ring 294 to tend to 
draw the upper ends of the link means 300,304 inwardly toward the carriage 
ring 294. Inward movement of such upper portions of the link means 300,304 
is limited and determined by adjusting studs 310 and nuts 312 mounted to 
the upper ends of the link means 300,304 and positioned to be brought into 
contact with inner and outer annular rings 314,316 secured to the carriage 
ring 294. 
Each lower end of a link means 304 has fixed thereto a curved actuator 
segment 318, and such actuator segments 318 are disposed in substantially 
circular fashion about the apparatus. Each actuator segment 318 defines 
three apertures 320,324,322 therethrough, with the central aperture 322 
being substantially circular, and the outer apertures 320,324 being 
elongated in the direction along the longitudinal axis of such actuator 
segment 318. An elastomeric ring 326 is positioned inwardly of and in 
contact with these actuator segments 318, and the elastomeric ring 326 has 
fixed thereto and embedded therein the head portions of bolts 328. Taking 
three adjacent bolts 328 as a group thereof, the central bolt 328 has an 
extended portion extending outwardly from the elastomeric ring 326 and 
through the central aperture 322 of the actuator segment 318, and a nut 
330 is secured to the extended end of the central bolt 328 to secure the 
central portion of the actuator segment 318 to the elastomeric ring 326. 
The bolts 328 on either side thereof have the extended portions thereof 
extending outwardly of the elastomeric ring 326 and through the respective 
elongated apertures 320,324 in the actuator segment 318. Each of the 
extended ends of these bolts is positioned through an aperture in a body 
332 which has a pair of rollers 334 fixed thereto, and a nut 336 is 
secured on each extended end of such bolts to bring the rollers 334 into 
contact with the actuator segment 318 and to secure the elastomeric ring 
326 to the ends of the actuator segment 318. It is to be understood that 
the next adjacent group of three bolts 328 associated with the elastomeric 
ring 326 is associated with another actuator segment 318 in like manner, 
such actuator segment 318 being in turn secured to the lower extending end 
of another link means 304, and so forth. 
The lower extended end of each link means 300 has fixed thereto a curved 
actuator segment 338 so that the curved actuator segments 338 together 
define a substantially circular configuration. Each actuator segment 338 
has disposed therethrough an aperture 339, and an elastomeric ring 340 is 
positioned outwardly of such actuator segments 338. The elastomeric ring 
340 has embedded therein the heads of a plurality of bolts 342, and the 
threaded end of each bolt 342 is disposed through the aperture 339 in a 
respective actuator segment 338. The elastomeric ring 340 is secured to 
each actuator segment 338 by a nut 344 threadably engaged with the 
extended end of a respective bolt 342. 
With the hydraulic cylinders 305 in their retracted states, the adjacent 
ends of the actuator segments 338 are quite close together and the 
adjacent ends of the actuator segments 318 are substantially one half inch 
part. Extension of the cylinders 305 pivots each associated pair of link 
means 300,304 so that the actuator segments 318 move inwardly to move the 
inner annular surface 346 of the elastomeric ring 326 inwardly, 
compressing the elastomeric ring 326 along its length during such 
operation, the gap between associated ends of the actuator segments 318 
allowing such compression and movement. At the same time, the annular ring 
340 is placed under tension and elongated to move the outer annular 
surface 348 thereof outwardly toward the elastomeric ring 326. 
As set forth above, it will be seen that upon actuation of the motor means 
to drive the chain 284, the entire assembly including the carriage ring 
294, substantially U-shaped members 296, link means 300,304, cylinders 
305, actuator segments 318, actuator segments 338, and elastomeric rings 
326, 340 can be raised and lowered at the desire of the machine operator. 
In the use of the apparatus 100, a toroidal core 146 is disposed on the 
support member 142 and seated in the recessed area thereof. It will be 
noted that with such toroidal core 146 so positioned, the central axis 147 
of the core 146 coincides with the central axes of the elastomeric rings 
326,340, and the central axis of the carriage ring 294, and also the 
central axes of the annular knife elements 218, 228. A circular sheet of 
elastomeric material 350 has its outer periphery fitted between a pair of 
rings 352, 353, the rings 352, 353 defining complimentary step portions 
354, 356, which properly seat and hold the elastomeric material 
therebetween (see FIG. 20), for securing the outer periphery of such 
elastomeric sheet material 350 relative to such rings 352, 353. The rings 
352, 353 with the elastomeric sheet material 350 are fitted on the outer 
annular table portion 252, and the hydraulic clamp cylinders 254 are 
actuated to bring the raisable and lowerable clamping arms 255 thereof 
into contact with the upper ring 352 to press the ring assembly into 
contact with the table portion 252. In such state, the toroidal core 146 
is disposed below the lower surface of the sheet material 350, and the 
elastomeric rings 326, 340 are in a raised position (FIG. 21). The table 
portions 252, 250 act as means associated with the frame means for 
positioning and supporting the sheet of elastomeric material 350 adjacent 
the so-supported core 146 along one side of the so-supported core 146. 
With such elastomeric sheet material 350 in position, the sheet material 
350, cylindrical portion 110, lower portion 112, and tank 234 (with cap 
bolt 240 removed) together form a closed chamber 349 (represented in 
simplified form in FIGS. 21-25). Liquid such as water 347 may be 
previously selectively added to or removed from the tank 234 to 
selectively vary the volume of closed air chamber 351 within such overall 
closed chamber 349. The chain 138 is then driven to raise the shafts 
132,134,136 to in turn raise the support member 142 and the core 146 
thereon to contact with the lower surface of the elastomeric sheet 
material 350. During such movement, it will be understood that the sheet 
of elastomeric material 350 is supported by the rings 352,353 on table 
portion 252 about the outer edge of the sheet of elastomeric material 350 
outwardly of the outer periphery 362 of the toroidal core 146, and that 
the sheet of elastomeric material 350 is supported by the table portion 
250 adjacent the center portion thereof inwardly of the inner periphery 
360 of the core 146. Upon further upward movement of the core 146, the 
effective volume of the air chamber 351 increases due to the movement of 
the elastomeric material 350, tending to draw the elastomeric material 350 
inward of the table portion 252 and outward of the table portion 250 
downwardly into such air chamber 351 (FIG. 22). The further upward 
movement of the core 146 further increases the air chamber size, further 
increasing the amount of pressure differential within the air chamber 351 
and outside the air chamber, i.e., between the side of the sheet of 
elastomeric material 350 facing the core 146 and the side of the sheet of 
elastomeric material 350 facing away from the core 146. Through such 
movement, elastomeric material of the sheet 350 is deposited onto the 
toroidal core 146 along a continuous path thereof, covering a side 
thereof. As best shown in FIG. 26, because of the increasing vacuum within 
the air chamber described above, in turn due to the increasing air chamber 
size, the elastomeric material 350 is applied to the core 146 in a 
particular manner. That is, elastomeric sheet material 350 is applied 
along one side 358 of the core 146, and along the inner and outer 
peripheries 360,362 of the core 146 to adjacent the opposite side 364 of 
the core 146. Due to such increasing chamber size and vacuum applied to 
the lower side of the sheet material 350 during movement of the core 146, 
and the stretching of elastomeric material yet to be deposited on the core 
146, the elastomeric material 350 applied to the inner periphery 360 of 
the core 146 continuously decreases in thickness in the direction away 
from the one side 358 of the core 146, and that applied to the outer 
periphery 362 of the core 146 is of continuous decreasing in thickness in 
the direction away from the one side 358 of the core 146. The positioning 
of the table portion 252 and table portion 250 may selectively be varied, 
i.e., for example through the raising and lowering of the table portion 
250 by means of the pin and collar structure described above, to vary the 
depositing characteristics during this operation. 
The elastomeric rings 326,340 are lowered through actuation of the chain 
284, (having been partially lowered during the initial raising of the core 
146), with the elastomeric rings 326,340 in their outward positions 
through the full contraction of the cylinders 305. The cylinders 305 are 
then extended and the continuous annular surface 348 of the elastomeric 
ring 340 is brought into contact with elastomeric material 350 deposited 
on the core 146 to stitch or apply force to an annular portion of the 
elastomeric material 350 deposited on the core 146 adjacent a continuous 
annular edge 371 of the so-deposited material to urge such annular portion 
against the core 146 (FIGS. 23 and 26). Such forcing is independent of any 
force used to initially deposit the elastomeric material 350 of said sheet 
against the core 146, such initial depositing taking place through the 
vacuum process described above. The continuous annular surface 346 of the 
elastomeric ring 326 is simultaneously brought into contact with a second 
annular portion of elastomeric material 350 deposited on the core 146 
adjacent another continuous edge 373 of the so-deposited material 350 
through pivoting of the link means 304, to stitch or apply force to this 
annular portion of elastomeric material 350 against the core 146, also 
independent of any force used to initially deposit elastomeric material 
350 against the core 146. 
The force applied by the annular surface 346 of elastomeric ring 326 and 
the force applied by the annular surface 348 of elastomeric ring 340 are 
applied adjacent the continuous edges 373,371 of the so-deposited 
elastomeric material 350. In fact, the force applied by the annular 
surface 346 of elastomeric ring 326 is applied to an annular portion of 
elastomeric material 350 which has been applied to the outer periphery 362 
of the core 146. The force applied by the annular surface 348 of the ring 
340 is applied to an annular portion of elastomeric material 350 which has 
been applied to the inner periphery 360 of the core 146. 
As set forth above, during outward movement of the elastomeric ring 340, 
such elastomeric ring 340 is placed in tension due to the movement of the 
actuator segments 338 relatively apart. The elastomeric ring 326 is placed 
in compression, due to the movement of the actuator segments 318 
relatively together. The elongated apertures 320,324 defined by the 
actuator segments 318 described above allow movement of the extended ends 
of the associated bolts 328 relative thereto, to allow proper compression 
of the elastomeric ring 326 along its length. It will also be understood 
that in a subsequent step to be described, such elongated apertures 
320,324 will allow the proper removal of the elastomeric ring 326 from the 
core 146 upon pivoting of the actuator segments 318 outwardly. 
To this point, the annular knife elements 218,228, adjacent the inner and 
outer peripheries of the core 146 respectively have been held in their 
lower position relative to the core 146 through proper actuation of the 
chain 206. At this point, with the continuous annular surfaces 346,348 of 
the rings 326,340 in contact with elastomeric material 350 on the core 
146, the knife elements 218,228, which may be of the heated type to 
provide efficient cutting, are raised through actuation of the chain 206 
to rotate the sprockets 170,172,174, to move the mounting structure 148 
toward the core 146 to raise the knife elements 218,228 into contact with 
elastomeric material 350 not deposited on the core 146 to press the 
knife-element-contacted portions of elastomeric material 350 against the 
elastomeric rings 340,326 respectively (FIG. 24). 
As set forth above, the mounting structure 148 is movably mounted relative 
to the support member 142 so that it may be moved relatively toward and 
away from the so-supported core 146. The slotted guide members 220,232 
allow movement of the knife elements 218,228 relative to the mounting 
structure 148 relatively toward and away from the so-supported core 146, 
and the resilient springs 212,230 urge the knife elements 218,228 
relatively toward the so-supported core 146. 
During the cutting operation, it will be seen that with the knife elements 
218,228 brought into contact with elastomeric material to be cut, the 
springs 212,230 allow such knife elements 218,228 to be moved downwardly 
so as not to apply too great a force to the elastomeric rings 340,326 
against which the cutting is done. Upon lowering of the walls 150,152, the 
springs 212,230 urge the knife elements 218,228 back into their normal 
upward positions, and the guide members 220,232 and particularly the slots 
therein provide for particularly proper positioning of the knife elements 
218,228, meanwhile allowing for such movement against the urging of the 
springs 212,230. 
The step of cutting away elastomeric material 350 not deposited on the core 
146 takes place adjacent and about the continuous edges 371,373 of the 
so-deposited elastomeric material 350. Subsequent to such cutting step, 
the knife elements 218,228 are lowered through actuation of the chain 206, 
the cylinders 305 are retracted and the carriage ring 294 and elastomeric 
rings 340,326 are lowered approximately one half inch through actuation of 
the chain 284 to position them so that upon extending actuation of the 
cylinders 305, continuous annular surfaces of the elastomeric rings 
340,326 will be brought toward and into continuous annular contact with 
the actual extended portion cut edges 375,377 of elastomeric material 350 
to press such edges 375,377 against the core 146, as shown in FIGS. 25 and 
27. The cylinders 305 are then retracted to move the elastomeric rings 
340,326 away from the core 146, and the rings 340,326 and associated 
assembly are raised above the core 146. At this point, the elastomeric 
material is situated on the core as shown in FIG. 28. 
Cut elastomeric material is then removed from the apparatus 100, and the 
core 146 including the elastomeric material 350 deposited thereon is 
turned over to again be positioned on the support element 142. After 
lowering of the support member 142, an additional sheet of elastomeric 
material associated with mounting rings 352,353 is mounted on the table 
portion 252, and the entire operation is repeated, with the additional 
sheet of elastomeric material positioned adjacent the toroidal core 146, 
along the other, opposite side 364 thereof. The additional elastomeric 
material 366 is deposited onto the toroidal core 146 along a continuous 
path thereof, in fact being applied along the other, opposite side 364 of 
the core 146, and along the inner and outer peripheries 360,362 of the 
core 146 to adjacent the one side 358 of the core 146. In a manner similar 
to the previous elastomeric material 350 applied to the core 146, this 
elastomeric material 366 applied to the core 146 is applied along the 
inner periphery 360 of the core 146 in a continuously decreasing thickness 
in the direction away from the other side 364 of the core 146 and 
overlapping the elastomeric material 350 previously applied to the inner 
periphery 360 of the core 146. Such elastomeric material 366 of the 
additional sheet applied to the core 146 also includes elastomeric 
material applied along the outer periphery 362 of the core 146 in a 
continuously decreasing thickness in the direction away from the other 
side 364 of the core 146 and overlapping the elastomeric material 350 
previously applied to the outer periphery 362 of the core 146. The 
additional deposited elastomeric sheet material 366 is cut in a manner 
similar to that described above, and force is applied to the extended cut 
portions of elastomeric material 366 extending from the so-deposited 
elastomeric material subsequent to the cutting to force such extended 
portions thereof against the elastomeric material 350 and the core 146. 
As seen in the drawings, the inner and outer peripheries 360, 362 of the 
core 146 are substantially straight in cross-section taken across the body 
of the core 146 perpendicular to the annular axis 368 of the core 146. 
This results in the tube structure 374 (FIG. 29), being made up of tube 
portion 376 of elastomeric material 350 and tube portion 378 of 
elastomeric material 366, also having inner and outer peripheries which 
are substantially straight and substantially uniform in thickness in 
cross-section taken across the body of the tube structure 374 
perpendicular to the annular axis 368 of the tube structure 374. The 
tapered surfaces of the inner and outer peripheries described above and 
applied in the manner as set forth above compliment each other to provide 
inner and outer peripheries of the tube structure 374 which are generally 
constant in thickness thereacross. The inner peripheral portion of the 
tube portion 376 and the inner peripheral portion of the tube portion 378 
overlap continuously fully along the straight cross-sectional inner 
periphery of the tube structure 374, and the outer peripheral portion of 
the tube portion 376 and the outer peripheral portion of the tube portion 
378 overlap continuously fully along the straight outer periphery of the 
tube structure 374. 
As set forth above, the volume of the closed gas chamber may be varied by 
adding water to or removing water from the tank 234, to vary the 
characteristics of vacuum applied to the lower surface of the elastomeric 
sheet material. 
It will be understood that the above-described operations may be automated 
to a great extent, and that, for example, limit switches and stops may be 
appropriately placed to determine proper positioning of, for example, the 
core 146 and elastomeric rings 326, 340. 
Shown in FIGS. 30-33 is another embodiment of apparatus 400 for forming a 
portion of a tube, i.e., a sidewall portion or portions, on a toroidal 
core 402. The apparatus 400 includes a main frame 404 made up of upright 
beams 406 and upper and lower horizontal beam means 408,410. Elongated 
upright outer shafts 412 are fixed relative to the main frame 404. The 
lower beam means 410 has associated therewith and rotatable relative 
thereto a sprocket and hub assembly 414,416, with internal threads of the 
hub 416 being in engagement with the external threads of a threaded, 
vertically disposed shaft 418, similar to the previous embodiment. The 
upper end of the shaft 418 has fixed thereto a table 420, such table 
defining apertures through which the respective shafts 412 are relatively 
movably disposed. It is to be seen that, similar to the previous 
embodiment, rotation of the sprocket 414 through, for example, chain and 
motor means (not shown), moves the shaft 418 along its longitudinal axis 
vertically, without rotation of the shaft 418, such vertical movement of 
the shaft 418 in turn raising and lowering the table 420 along the shafts 
412 and relative to the frame 404 as desired. 
The table includes as a part thereof a circular plate 422, which in turn 
has fixed thereto a plurality of angled positioning members 424 as shown. 
A cylindrical wall 426 is fixed to the plate 422, and fixed to the upper 
surface of the wall 426 is a circular plate 428. Such circular plate 428 
has fixed to the outer periphery thereof an annular heated knife element 
430. The plate 428 defined bores through which are relatively movably 
disposed studs 432. The lower ends of the studs 432 have nuts 434 
threadably engaged therewith, and the upper ends of the studs 432 are 
threadably engaged with a circular table 436. Resilient springs 438 are 
disposed about the respective studs 432, and are interposed between the 
plate 428 and the table portion 436 to resiliently urge them apart. The 
nuts 434 limit the relative movement of the plate 428 and table portion 
436 apart under the resilience of the springs 438. However, it will be 
seen that the table portion 436 may be moved downwardly relative to the 
plate 428 against the resilience of such springs 438. 
The table portion 436 defines an annular flange portion 440, and such 
annular flange portion 440 defines bores through which are relatively 
movably disposed studs 442. The upper ends of such studs 442 are fixed to 
a circular angled table portion 444 defining a central opening, and nuts 
446 are disposed on the lower ends of the studs 442. Resilient springs 448 
are disposed about the respective studs 442, and are interposed between 
the flange portion 440 and the angled table portion 444, to resiliently 
urge them apart, the movement of the table portion 444 away from the 
flange portion 440 being limited by the nuts 446. It will be seen that the 
angled table portion 444 may be moved downwardly relative to the flange 
portion 440 against the resilience of the springs 448. 
The table 420 also defines threaded bores with which bolts 450 are 
threadably engaged, to extend upwardly from the table 420, being fixed in 
position relative to said table 420 by means of lock nuts 452. 
Positioned upwardly of the table 420 is table 454, which also defines 
apertures through which the respective shafts 412 are relatively movably 
disposed. The table 454, it will be seen, is thus also movable upwardly 
and downwardly relative to the shafts 412 and relative to the frame 404. 
The table 454 in its lowermost position rests on the extended ends of 
bolts 456 which are threadably engaged with threaded bores defined by 
plates 458 fixed to the upright beams 406. Lock nuts 460 are also included 
in association with such bolts 456 to selectively fix the positioning of 
such bolts 456 relative to the plate 458. 
The table 454 defines a large central circular opening through which may 
extend the table portion 436, table portion 444, and the annular knife 
element 430. Extending inwardly of the inner periphery of such table 454 
at the opening thereof and slightly below the table 454 are support 
members 462 as shown. The table 454 defines a plurality of apertures 464 
therethrough, through which the respective bolts 450 may extend upon 
raising of the table 420 relative to the table 454. 
Yet another table 466 defines apertures through which the shafts 412 
relatively movably extend, so that the table 466 is also movable upwardly 
and downwardly relative to the shafts 412 and the frame 404. The table 466 
defines a large central circular opening, and has fixed thereto adjacent 
such opening annular flange means 468, to which is in turn fixed an 
elastomeric ring 470. The table 466 defines threaded bores through which 
are threadably disposed bolts 472, the positioning of which may be 
adjusted and locked in place by means of lock nuts 474 associated with the 
bolts 472. 
Fixed to the upper beam means 408 is a cylindrical body 476 including a 
cylindrical outer wall 478, a top wall portion 480, and a bottom wall 
portion 482 defining a large circular central opening. A threaded shaft 
484 is disposed through the upper beam means 408 and the lower end of such 
shaft 484 has fixed thereto a plate 486. Guide members 488 are fixed to 
the top wall portion 480 and relatively movably extend through respective 
bores defined by the plate 486. A hub and sprocket assembly 490,492 is 
associated with the upper portion of the shaft 484 and the beam means 408, 
similar to the previously described systems, and it will be seen that 
rotation of the sprocket 492 moves the shaft 484 vertically, without 
rotation of the shaft 484, to in turn move the plate 486 upwardly and 
downwardly relative to the frame 404 as selected by the operator of the 
machine. 
A plurality of rods 494 have their lower ends fixed to the plate 466 by 
means of nuts 496, and such rods 494 extend upwardly and relatively 
movably through apertures 498 defined by the top wall portion 480. The 
upper ends of such rods 494 have threadably engaged therewith nuts 500, so 
that the lowermost position of the table 466 is determined by the 
contacting of the nuts 500 with the top wall portion 480 under the weight 
of the table 466. 
Yet another table 502 is positioned upwardly of the table 466 and below the 
body 476, and a plurality of hydraulic cylinders 504 interconnect the beam 
means 408 and table 502. The rods 494 are movably disposed through 
appropriate apertures 503 provided in the table 502. Extension of the 
hydraulic cylinders 504 positions the table 502 in its lowermost position 
shown in FIGS. 30, and retraction of the cylinders 504 may bring the table 
502 into contact with the bottom portion 482. The table 502 also defines a 
large circular central opening therethrough. 
Fixed to the plate 486 and extending downwardly therefrom are inner and 
outer cylindrical walls 506,508. Disposed outwardly of the inner wall 506 
is an annular angle member 510, the position of which may be selected 
relatively toward and away from the plate by means of bolts 512 relatively 
movably disposed through bores in the radial portion 514 of the angle 
member 510 and in threaded engagement with threaded bores defined by the 
plate 486 (FIG. 30), and bolts 516 in threaded engagement with threaded 
bores in the radial portion 514 of the angle member 510 and which may be 
brought into contact with the plate 486 (FIG. 32). An elastomeric ring 518 
is disposed about the cylindrical portion 520 of the angled member 510, so 
as to be movable relative thereto along the longitudinal axis of such 
cylindrical portion. A plurality of bolts 522 are relatively movably 
disposed through bores in the radial portion 514 and have their extended 
ends in threaded engagement with the elastomeric ring 518. Helical springs 
524 disposed about such bolts 522, enaging the radial portion 514 and the 
elastomeric ring 518, urge the elastomeric ring 518 downwardly away from 
the radial portion 514, to bring the heads of the bolts 522 into contact 
with the radial portion 514. It will be seen that the elastomeric ring 518 
may be moved toward the radial portion 514 and the plate 486 upon force 
applied thereto against the resilience of the springs 524. 
The wall 508 has inwardly disposed thereof another annular angle member 
526, made up of a cylindrical portion 528 and a radial portion 530. The 
angle member 526 is adjustably mounted to the plate 486 by means of bolts, 
similar to the angle member 510. 
A plurality of bolts 532 are relatively movably disposed through bores in 
the radial portion 530, and have their extended ends in threaded 
engagement with an elastomeric ring 534 disposed within the cylindrical 
portion 528. A plurality of resilient helical springs 536 are disposed 
about the respective bolts 532, and tend to urge the elastomeric ring 534 
downwardly away from the radial portion 530 and the plate 486, the 
downward movement of such elastomeric ring 534 being limited by the 
contacting of the heads of the bolts 532 with the radial portion 530. It 
will be seen that the elastomeric ring 534 may be moved relatively toward 
the radial portion 530 and plate 486, upon application of force to the 
elastomeric ring 534 against the urging of the springs 536. 
The plate 486, wall 506, wall 508, angle member 510, and angle member 526 
make up mounting means 540 which are movable relative to the frame 404, 
for mounting the elastomeric rings 518,534. 
An annular heated cutting element 542 is fixed to the cylindrical portion 
528 outwardly of and generally about the elastomeric ring 534. Another 
elastomeric ring 544 is fixed to the cylindrical portion 520 generally 
inwardly of the elastomeric ring 518. 
Fixed to the upper portion 480 and extending downwardly therefrom through 
appropriate bores in the plate 486 to be movable relative thereto are 
mounting legs 546, which have fixed to their extended lower ends a table 
portion 548 as shown. 
In the operation of the apparatus 400, the tables 420,454,466,502 are 
positioned as shown in FIG. 30. A toroidal core 402 as shown (which may 
for example already have elastomeric material as a part thereof) is 
positioned on the table 454, being supported by the inner periphery of the 
table 454, and the support members 462. A sheet of elastomeric material 
550 disposed between two rings 552,554 (FIG. 32) is positioned on the 
table along one side of the core 402, similar to the previous embodiment. 
After the sheet material 550 is placed on the table 502, the cylinders 504 
are retracted to bring the sheet material 550 into engagement with the 
bottom portion 482 so that the body 476 and sheet material 550 form a 
closed chamber, and a low air pressure may be applied to this closed 
chamber. The sprocket 414 is then rotated to raise the table 420, the 
bolts 450 passing through the appropriate apertures 464 as described 
above. The table 420 is raised sufficiently relative to table 454 so that 
the toroidal core 402 is seated on the plate 422 about the angled guides 
424, such angled guides 424 acting to properly center the toroidal core 
402 relative to the table 454. The plate 422 is provided with appropriate 
openings in which the support members 462 seat upon the bringing of such 
table 420 close to the table 454. During such operation, of course, the 
annular knife element 430 and table portions 436,444 are being raised with 
the table 420. Upon such contacting of the support members 462 with the 
table 454, the table 420 and table 454 move upwardly together along the 
shafts 412, until the heads of the bolts 450 contact the table 466. The 
positioning of such heads of bolts 450 is chosen so that the elastomeric 
ring 470 is now carried quite close to the surface of the toroidal core 
402. Upon such contacting of the heads of the bolts 450 with the table 
466, the table 420, table 454 and table 466 move upwardly together 
relative to the frame 404. 
The table 420, table 454 and table 466 are raised together, along with the 
toroidal core 402, to bring the toroidal core 402 into continuous annular 
contact with the elastomeric sheet material 550, so that elastomeric 
material 550 of said sheet thereof is deposited on the toroidal core 402 
along a continuous path thereof. At approximately this time, the table 
portion 436 and table portion 548 are quite close together with 
elastomeric material 550 of the sheet thereof squeezed therebetween, so 
that the central portion of the sheet of elastomeric material 550 is 
supported, along with the outer periphery thereof. The resilience of the 
springs 438, of course, provides for proper holding of such portion of the 
sheet material between the table portions 436,548 and openings 551 are 
provided in the plate 422 and table 420 to allow for downward movement of 
the studs 432 relative thereto (FIG. 31). 
The toroidal core 402 is further raised through movement of the table 420, 
table 454 and table 466, until the extended ends of the bolts 472 contact 
the already-raised table 502 to determine the upward limit of movement of 
the toroidal core 402. The sprocket 492 is then rotated through 
appropriate chain and motor means to lower the plate 486 and elastomeric 
rings 518,534,544 therewith, to bring continuous annular surfaces of the 
elastomeric rings 518,534 into continuous annular contact with elastomeric 
sheet material 550 deposited on the core 402. The elastomeric rings 
518,534 are movable relative to the mounting means 540 relatively toward 
and away from the core 402, the resilient springs 524,536 allowing such 
movement. Similar to the elastomeric rings in the previous embodiment, 
such elastomeric rings 534,518 act to apply force to or stitch annular 
portions of the elastomeric material 550 to the core 402 independent of 
the initial force which deposited elastomeric material on the core 402. 
Further downward movement of the mounting means 540 results in the annular 
knife element 430, now adjacent the inner periphery of the core 402, being 
brought into contact with elastomeric sheet material 550 not deposited on 
the core 402, the cutting force of such annular knife element 430 being 
applied through the elastomeric material to the elastomeric ring 544. Such 
further movement also results in the annular knife element 542, now 
adjacent the outer periphery of the core 402, being brought into contact 
with elastomeric material 550 not deposited on the core 402, such cutting 
force actually being applied through such elastomeric sheet material not 
deposited on the core 402 to the elastomeric ring 470. 
Such positioning of appropriate elements is shown most clearly in FIG. 33. 
It will be seen that with the particular association of the elastomeric 
rings 518,534 and mounting means 440, the elastomeric rings 518,534 are 
moved against the resilience of springs 524,536 under the force of the 
toroidal core 402 applied thereto to allow the annular knife elements 
542,430 to come into play. 
Upon completion of the operation heretofore described, the sequence of 
steps may be reversed to lower the toroidal core 402, which has deposited 
thereon such portion of elastomeric material 550. The extending cut edges 
may then be pressed to the core 402 by any appropriate means. For example, 
the toroidal core 402 may be lowered sufficiently to bring the outer cut 
edge below the elastomeric ring 470, and the toroidal core 402 may then be 
raised so that the elastomeric ring 470 acts on the outer extended portion 
cut edge to press such extended portion cut edge against the core 402. In 
this manner, sidewall portions of the tube to be formed may be deposited 
on the core 402. It is to be understood that, again, the core 402 being 
operated on may already include appropriate elastomeric material to which 
are added the sidewall portions through operation of the apparatus 400.