US2058233A - Vulcanizer - Google Patents

Description

Oct. 20, 1936.

c. lvERsoN l VULCANIZER Filed 'June 28, 1955V 4 Sheets-Sheet 1 Z EL ATTORN EY OC. 20, 1936. c Q WERSON 2,058,233

VULCANIZER Filed June 28, 19.35 44 Sheets-Shea?I 2 a INVEN TOR j CA-ro IVERS N er MMX.

/ ATT N EY Oct. 20, 1936. Q WERSON 2,058,233

VULCANI ZER Filed June 28, 1955 4 Sheets-Sheet 3 INVENTOR CATo IVERSON ATTQRNEY Patented Got. 20, 1936 JNTED STATES rATENT ori-isla VULCANIZER Cato Iverson, Akron, Ohio, assignor to National Rubber Machinery Company, Akron, Ohio, a

corporation of Ohio Application June 28, 1935, Serial No. 28,861

10 Claims.

" thereby to effect uniformity of heat in the latter;

to provide a vulcanizer of the character mentioned wherein the molding parts are so positioned, when open, as to facilitate the cleaning thereo-f; to provide simple and eil'cient mechanism for ejecting the finished work from the mold; to provide a vulcanizer that opens to a position that facilitates the mounting of work therein and its removal therefrom; and to provide for the safety of the operator of the vulcanizer. Other objects will be l manifest as the specification proceeds;

Of the accompanying drawings,

Figure 1 is a side elevation of the improved vulcanizer, in its preferred form, in its closed or operative position; i

Figure 2 is a section on the'line 2--2 thereof;

Figure 3 is a section on the line 3-3 of Figure 2; and

Figure 4 is a section similar to Figure-3 showing the vulcanizer in its open or inoperative position.

Referring to the drawings, it will be seen that the vulcanizer comprises a pair of upstanding side frames IU, I0 that are connected at their tops by a. tie rod I I, and are connected at their bottoms by a front transverse spacer member I2and a rear transverse spacer member I3. Journaled at` its respective ends in the side frames I, near the top of the latter, is a horizontal shaft I4 upon which is mounted an upper press head I5, said head being non-rotatably secured to said shaft by a pair of set screws I6, IS. Journaled at its respective ends in the side frames I 0, near the bottom of the latter, is a horizontal shaft I8, of which medial portion I8a, between said frames, is eccentric with relation to the end-journals thereof. Journaled upon said eccentric portion I8a of shaft I8 is a forked arm or link I9 that has a pair of opposed stub shafts 20, 2B journaled in its free end portion, and a lower press head 2| is mounted upon said stub shafts and secured theretoY by set screws 22, 22. Mounted upon the adjacent faces of the upper and lower press heads I5 and 2| are the respective mating halves or sections 24, 25 of an annular, two-part, steam-jacketed cavity mold, shown herein as a tire mold, although obviously other similar types of molds may be employed.

(o1. iks-17) The mold sections'may be secured to the pressV heads inany desired manner, asby means o1' bolts 26, 26. It will be observed that YWhereas shafts I4 and I8 are parallel to each other, theyare not in the same vertical plane, shaft I4 beingpositioned somewhat rearwardly of shaft I8. The arrangement is such that the mold sectionsV 24, 25 incline downwardly toward the rear both in their open and in their closed positions.

The eccentricity of the shaft I8 is utilized for effecting a perfect, tight mating of the mold sections 24, 25 in the closed position of the vulcanizer,

and to this end means is provided for turning said shaftv angularly whereby the lowerghead 2| and mold section 25 thereon may be moved toward o-r away from upper mold section 24. Said means comprises a crank or lever 28 that is secured upon one journal of the shaft I8 that projects beyond frame I0, (see Figure 2), said crank projecting upwardly and being engaged on opposite sides by adjusting screws 29, 23that are threaded through respective ears 30 formed on reinforcing ribs on the outer face of said frame. The shaft I8 andY crank 28 are formed with interengaged complemental teeth whereby relative movement between 2 the members normally is prevented, but relative angular adjustment is permitted. By the arrangement described the vulcanizer is adapted to utilize a large .number of molds, notwithstanding the fact that said molds may Vary somewhat from a standard thickness.Y Y

The upper press head I5 and the lower press head 2| are hingedly connected to each other and to this end the upper press head is provided with a pair of parallel', rearwardly extending bracket arms 3| and the .lower press head is formed with a pair of parallel, rearwardly extending arms 32. Journaled in the free ends of arms 32 is a pivot pin 33 that is of square section in the region be-V tween said arms. The pivot pinV 33 extends through elongate slots 34 formed in the respective bracket arms 3|, and the latter are secured to said pivot pin by means of adjustable set screwsV 35, 35. The arrangement permits the hinge pin 33 to be adjusted relatively of the arms 3 I, which adjustment is utilized whenever the position of the lower press head 2| is altered by angular adjustment of crank 28. The hinge pin 33 is disposed in a plane that is somewhat (about one inch) above the parting plane of the mold sections 24, 25 -for a reason that presently will be explained.

They opening and closing of` the vulcanlzer is effected by power mechanism that is connected to the upper press head and to av` fixed point on the vulcanizer structure. To this end a housing 31 is pivotally mounted at 38 between the bracket arms 3| of upper press head I5, the pivot 38 being above and somewhat rearwardly of hinge pin 33. Journaled within the housing 31 is a longitudinally extending, axial sleeve 39 that is interiorly threaded to receive an elongate screw 40 that has its lower end pivotally connected at 4I between a pair of rearwardly extending arms 42 formed on the rear spacer member I3. Keyed to sleeve 39, within housing 31, is a gear 43 that is meshed with a pinion 44, the latter being keyed to the shaft of a motor 45 that is carried upon the housing 31, exteriorly thereof. That portion of the housing that contains the aforesaid gearing is provided with a removable cover 46, and the latter carries a tubular guard 41 into which the screw 46 is moved in the open position of the vulcanizer, shown in Figure 4. The motor 45 is a standard reversible motor, and operation thereof will move the housing 31 longitudinally of the screw 40 and thus move the mold sections between the open and closed positions shown in Figure 4 and Figure 1 respectively. It is possible to substitute a fluid pressure cylinder for the motor 45 and associated mechanism without departure from the spirit of the invention.

'Ihe motor 45 is operated from any suitable source of electrical power, and manually operated starting switches (not shown) are provided for starting the motor in either of its alternative positions. The operative cycles of the motor automatically are terminated when the vulcanizer attains its fully open or fully closed position, and to this end a suitable limit switch is provided. As shown in Figure 1 said limit switch comprises a stud 50 that is mounted axially upon an end face of shaft I4, said stud having a pair of radial contact arms 5I, 52 secured thereto at an angle to each other. Swivelled upon the stud 56 is an arm 53 that normally is maintained in determinate angular position by a pair of opposed tension springs 54, 54. The arm 53 carries a pair of electrical contacts 55, 56 that are engageable by the respective contact arms 5I, 52 when the latter are turned angularly by rotation of shaft I4 during the operation of the vulcanizer. Said electrical contacts are so arranged in the electrical circuit controlling motor 45 as to effect the cutting olf of current to the latter when contacts 5I, 55 engage each other or when contacts 52, 56 engage each other. The swivelling of the contact arm 53 allows for coasting of shaft I4 after current to the motor 45 is cut off. In the event of failure of the limit switch to stop motor 45, substantial over-running is prevented by means of a pair of positive stops. Of the latter, 51 is one of a pair of lugs projecting from the inner faces of respective frames ID and engageable with the arm I9 in a slightly over-center position of said arm in the closed position of the vulcanizer. The other positive stop is an upstanding abutment 53 formed on the top of front spacer member I2 and engageable with the bottom of lower press head 2l if the latter moves but little beyond its normal open position shown in Figure 4.

As hereinbefore stated, the mold sections 25, 25 are of the usual steam-jacketed type, and suitable piping 6I), 60 is provided, at the rear of the press, for conducting steam thereto and conducting steam and condensate therefrom, the arrangement being such that the .steam circulates first through the upper mold section, and passes therefrom into the lower mold section. 'Ihe piping 60 is hingedly jointed at 6 I, 6I to permit the opening and closing movements of the press. Because the mold sections at all times are tilted so as to be lower at the rear, drainage of the steam jackets through the piping 66 is facilitated and uniform heating of the mold is effected. To prevent dissipation of heat in the mold sections by conduction through the upper and lower press heads I5, 2|, the mold-contacting faces of said press heads are annularly recessed at 62, 62, and said recesses filled with a suitable composition 63, 63 of low thermal conductivity, such as asbestos composition. The arrangement is such that there is relatively small metal-to-metal contact between the mold and the press heads, and relatively little loss of heat through the latter.

The molding cavities of the mold sections 24, 25 are shaped to receive an annular, pneumatic tire casing 65, the latter being provided with the us'ual expansible core 6G for providing the necessary internal pressure during vulcanization of the tire. The inner perimeters of the respective molding cavities are recessed to receive the respective sections of a bead clamping ring or clip ring of which the upper section 61 is fixedly secured to the upper mold section 24. The lower bead clamping ring section, designated 68, is mounted upon the upper end of a pair of parallel guide rods 69, 69 that extend downwardly through suitable apertures formed in the lower press head 2 I, and project from the bottom of the latter. The guide rods 69 are axially slidable in said apertures, whereby they are adapted to move the bead ring 68 relatively of the mold section 25 in an axial direction, but prevent any angular movement of said bead ring. The guide rods 69 project a sufficient distance below the press head 2I that they engage the abutment 58 when the vulcanizer is open, as shown in Figure 4, with the result that they are moved upwardly and the bead ring 68 thereon is lifted a substantial distance above the mold section 25.

During vulcanization, the tire 65 is expanded by fluid pressure, usually water at vulcanizing temperature, that is circulated within the expansible core 66. To this end the latter is provided, at diametrically opposite points of its inner periphery, with valve stems 1I, 1I that have their ends, exteriorly of the core structure, provided with vrespective coupling members 12 of a known construction. The lower bead ring 68 is suitably slotted to receive the valve stems 1I, the arrangement assuring that the valve stems always will be determinately positioned in the vulcanizer. Mounted in respective lugs 13 projecting radially inwardly from the inner periphery of lower mold sections 25 are coupling members 14, 14 that have fluid-tight engagement with coupling members 12 when brought into face to face engagement therewith. Coupling members 14 are connected to suitable pipe lines 15, 15 extending to a source of fluid pressure (not shown), said pipe lines being hingedly jointed at 16, 16 to accommodate the movements of the vulcanizer. Radial lugs 11, 11 are formed on the inner periphery of the upper mold section 24 and are adapted in the closed position of the vulcanizer, to engage the coupling members 12, 12 and to force them against the respective coupling members 14, whereby a fluid-tight connection between the coupling members is assured.

The operation of the apparatus is as follows. When the vulcanizer is in its open, inoperative position, the respective parts thereof are in the positions shown in Figure 4, with the lower bead ring 68 in elevated position above the lower mold section 25. An unvulcanized tire casing 65 with expansible core 86 mounted therein is then positioned upon the lower bead ring in determinate angular position as shown, the valve stems 1I of said core seating in the slots in said bead ring' whereby the coupling members 12 are aligned with coupling members 14. The tire is thus supported out of engagement with the hot lower mold section until the vulcanizer starts to close.

Closing of a starting switch (not shown) starts the motor vto rotating in the direction that propels the housing 3l longitudinally of the screw 4B, toward the free end of the latter, with the result that the upper head I5 is tilted or moved angularly upon its fixed pivot I4, therebyT swinging pivot pin 33 about the same axis and irnparting to lower head 2I an arcuate, rising movement of translation about shaft I8 as an axis. As the lower head 2| rises it moves relatively of the tire and lower bead ring 68 until the said tire and bead ring seat in their respective cavities in the lower mold 25, the latter thereafter carrying the tire and bead ring with it.

The movement of the press heads and mold sections as described continues until the mold sections attain the fully closed position shown in Figures l and 3 of the drawings, at which time the pivotal connection 20 between the arm I9 and lower head 2| will be in alignment with pivot points I4 and I8, or slightly over center with relation thereto. From the foregoing, it will be seen that the arm I9, upper and lower press heads and upper and lower mold'sections constitute, in effect, a toggle adapted unyieldingly to oppose the internal pressure in the work during the vulcanizing operation. The moving members of the vulcanizer come to rest in the closed position shown as the motor 45 ceases rotating, which is the result of engagement of contacts 5I, 55 of the limit switch momentarily prior thereto. Because the pivot pin 33 is positioned above the parting plane of the mold, the mold sections approach each other, in the final stage of their closing movement, substantially in parallelism, thereby obviating the possibility of displacing the work or pinching it between the mold sections such as frequently occurs in vulcanizers employing hinged sections.

After the vulcanizer is closed, fluid pressure is admitted to the expansible core 66 and the tire 85 is vulcanized in the usual manner. After the tire is vulcanized, the pressure uid is evacuated from the core 66, and the vulcanizer is opened by reversing the operations previously described, the initial separation of the mold sections being eifected while they are maintained in parallelism. As the vulcanizer opens, the work remains in the lower mold section due to the fact that the upper mold section previously has been lubricated with soap. As the lower press head approaches its lower position, the lower ends of guide rods 69 engage abutment 58, whereby further movement of lower bead ring 68 is arrested. Continued downward movement of the lower press head strips the lower mold section away from the tire, so that the latter and lower bead ring are positioned above the lower mold section when the latter subsequently comes to rest. The vulcanized tire is then easily lifted off the bead ring. This completes a cycle of operation which may be repeated as desired.

When the vulcanizer is open, the distribution of weight is such that there is no possibility of the upper mold section accidentally dropping or cilitates the mounting and removal of work from the vulcanizerfand the cleaning and lubricating of the molding cavities. The vulcanizer has relatively few parts so that maintenance costs are low, and it achieves the other advantages set out in the foregoing statement of objects.

Modifications of the invention may be` resorted to without departing from the spirit of the invention or the scope of the appended claims.

What is claimed is:

1. A vulcanizer comprising a pair of movable, annular, press heads adapted to carry respective mating mold sections, one of said heads being pivoted directly to a diametrically disposed axis having a fixed situs, the other head being pivotally mounted upon a diametrically dispo-sed axis that is movable relatively of the axis of the firstmentioned head, and means for tilting the'rstmentioned head upon its axis and concurrently moving the axis of the other head to effect opening or closing of the vulcanizer.

2. A vulcanizer comprising a pair of press 'heads that are hinged together at one side, one

of said heads being a floating head and the other head being pivotally supported directly upon an axis having a xed situs, and means for moving Y the hinge of the press angularly about the said pivotal support as an axis to open or close the vulcanizer.

3. A vulcanizer comprising upper and lower movable press heads adapted to carry respective mating mold sections, the upper press head being pivoted directly upon an axis having a fixed situs, the lower head being pivotally mounted upon an axis that is movable relatively of the axis of the upper head, a hinge connecting said upper and lower heads, which hinge is disposed laterally of the parting plane of the mold sections, and means for tilting the upper head and concurrently moving the axis of the lower head to effect opening or closing of the vulcanizer.

4. A vulcanizing press comprising a frame, a pair of movable press heads adapted to carry respective mating 'mold sections, one of said heads being pivotally mounted directly upon said frame, a pivotally mounted toggle arm upon the free end of which the other press head is pivotally mounted, an adjustable hinge connection between said press heads, and a power member connnected to one of said press heads at a point removed from said hinge and to a xed point adapted concurrently to swing said toggle arm and to tilt the other head on its axis to effect opening or closing of the press.

5. A vulcanizing press comprising upper and lower movable press heads adapted to carry respective mating mold sections, a freely journaled shaft upon which the upper press head is mounted, a pivotally mounted toggle arm upon the free end of which the lower press head is pivotally mounted, a hinge connection between said press heads, an electrically controlled power member connected to one of said press heads and to a fixed point adapted concurrently to swing said toggle arm and to tilt the upper head and its shaft to effect opening and closing of the press, and a limit switch associated with said shaft adapted to terminate the operation of said power member after determinate angular movement of said shaft.

6. In a vulcanizer of the character described, the combination of a pair of mating mold sections, a hinge connecting said sections and being adjustable relatively of one of them, supports for said sections permitting swinging motion of the sections thereon, one of said supports comprising an eccentric shaft that is angularly adjustable to alter the position of one of said sections from and toward the other section, and means for swinging said sections on said supports.

'7. A vulcanizer of the character described comprising a pair of mating mold sections, a hinge connecting said sections and being adjustable relatively of one of them, supports for said sections permitting swinging movement of the sections thereon, one of said supports comprising a toggle arm, an eccentric shaft engaged by one end of said toggle arm, said shaft being angularly adjustable to adjust the position of the sections axially with relation to each other, and means for swinging said sections on said supports.

8. A combination as defined in claim '7 in which the means for swinging the mold sections is a power member that is connected to the mold structure to a point removed from the hinge thereof.

9. A vulcanizer comprising a frame, a pair of movable press heads adapted to carry respective mating mold sections, one of said heads being pivoted directly to said frame, and means for moving said last mentioned head about its pivot and for imparting a movement of translation tothe other head to effect opening and closing of the vulcanizer.

10. A vulcanizer comprising a frame, a pair of movable press heads adapted to carry respective mating mold sections, one of said heads being pivoted directly to said frame, a pivoted arm connected between said frame and the other of said heads, and a single power means for moving said heads to effect opening and closing of the vulcanizer.

Y CATO IVERSON.

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