Tire building machine

• US 3,867,231 A
• Filed: 06/28/1972
• Issued: 02/18/1975
• Est. Priority Date: 06/28/1972
• Status: Expired due to Term

• Current Assignee: William R. Casey
• Original Assignee: William R. Casey
• Inventors: Casey, William R.
• Primary Examiner(s): Cosby, Clifton B.
• Assistant Examiner(s): Kittle, John E.
• Application Number:
  US05/266,885
• Time in Patent Office: 965 Days
• Field of Search: 156/414,415,416,417,131,132,135,398,400,403,420
• US Class Current: 156/415
• CPC Class Codes: B29D 30/245 Drums for the single stage building process, i.e. the building-up of the cylindrical carcass and the toroidal expansion of it are realised on the same drum expansion to a toroidal shape B29D30/36
• CPC Class Codes: B29D 30/36 Expansion of tyres in a flat form , i.e. expansion to a toroidal shape independently of their building-up process, e.g. of tyres built by the flat-tyres method or by jointly covering two bead-rings

Abstract

Apparatus for building a tire having a circumferentially inextensible belt, and particularly a multi-condition tire building drum providing in an intermediate condition, a high crown firmly supported for stitching a cylindrical tire band, a radially expansible sleeve secured radially on and extending axially between a pair of drum end assemblies movable toward and away from each other and cooperating with the sleeve to form a chamber into which air is admitted to expand the sleeve into toroidal form as the end assemblies are moved toward one another, bead locating segment assemblies adjacent to and axially outboard of the sleeve ends to locate beads of the tire in firm axial and concentric position as the tire is shaped from a cylindrical to a toroidal form and particularly useful in securing the beads in proper location during conventional stitching operations. The drum features expansion of the internal supporting segments by rotation of scroll plates each having a plurality of spiral cam grooves by which the segments are moved radially inwardly and outwardly.

Claims

1. In tire building apparatus for building a tire having therein a circumferentially inextensible belt;

a building drum comprising an expansible sleeve providing a continuous exterior surface for contiguously supporting said tire and terminating in radially fixed inwardly turned ends;

a hollow cylindrical center shaft disposed coaxially within said sleeve and extending axially outwardly of said ends;

a pair of rigid end bodies mounted coaxially and corotatably on said shaft for movement toward and away from each other, said ends being secured respectively to said bodies;

a plurality of rigid interior support segments mounted within said sleeve on each of said bodies for movement radially of the drum rotation axis and cooperable to provide in one condition of said drum firm continuous cylindrical support to said sleeve between said ends; and

a plurality of bead locating segments disposed close to and axially fixed outwardly of each of said inwardly turned ends and supported for movement radially of the drum axis, a rigid annular member mounted outwardly of each of said ends for coaxial movement toward and away from the respectively associated end, and a plurality of rigid links each pin-connected to one said member and respectively to one of said bead locating segments to maintain the segments concentric with the drum axis.

2. Apparatus as claimed in claim 1, including a cylindrical housing having a flange portion at the proximate end thereof secured airtightly to each of said end bodies and a second flange portion airtightly and slidably engaging said center shaft axially outwardly of the respective end body, said housing being provided with a coaxial cylindrical bore therein, said rigid annular member comprising a piston slidable in said bore in response to change in air pressure within said bore.

3. Apparatus as claimed in claim 2, the first said flange portion extending radially outWardly about said housing and comprising a plurality of cylindrical bores equally spaced angularly about and extending radially of said axis, a plurality of pistons each mounted slidably in a respectively associated bore, each of said bead locating segments being mounted on the radially outward end of the respectively associated one of said pistons, said bead locating segments being provided with bead locating surfaces, the latter said surfaces each being shaped to conform circumferentially to the radially inner surface of a bead for said tire.

4. Apparatus as claimed in claim 3, said bead locating surfaces each including a surface portion extending radially outward of the minimum diameter of such bead and cooperable with said sleeve while the latter is in a radially expanded condition to resist dislodgment of said bead.

5. In tire building apparatus for building a tire having therein a circumferentially inextensible belt;

a building drum comprising an expansible sleeve providing a continuous exterior surface for contiguously supporting said tire and terminating in radially fixed inwardly turned ends;

a hollow continuous cylindrical center shaft disposed coaxially within said sleeve and extending axially outwardly of said ends;

a pair of rigid end bodies mounted coaxially on and corotatably with said shaft for sliding movement toward and away from each other on said shaft, said ends being secured in radially fixed relation respectively to said end bodies;

a plurality of rigid interior support segments, including a first set of greater arcuate width and a second set of lesser arcuate width disposed in alternating sequence circumferentially about each said end body and mounted within said sleeve on each of said bodies for movement radially of the drum rotation axis and cooperable to provide in one condition of said drum firm continuous cylindrical support to said sleeve between said ends;

means for moving said segments radially comprising a scroll plate carried by each of said end bodies for coaxial movement respectively therewith and for rotation relative to said end bodies about said axis;

each of said end bodies comprising a plurality of guideways extending radially of the axis, each of said interior support segments having a guide member extending radially of the axis slidable radially in the respectively associated guideway;

groove follower means on each said guide member and cam groove means on each said scroll plate cooperably interengaging to move said segments radially of the axis in response to rotation of said scroll plate; and

means on each said scroll plate comprising an annular groove concentric therewith and a plurality of wheels mounted on each respectively associated end body, said wheels having peripheral rims interengaging said annular groove and cooperable to move said scroll plate axially of the drum together with such end body and to accommodate relative rotation of said scroll plate with respect to said end body.

6. Apparatus as claimed in claim 5, said cam groove means comprising a plurality of grooves extending in coplanar spiral paths spaced angularly about each respective scroll plate, said follower means on said radial guide members each engaging respectively one of said grooves;

and said plurality of grooves comprising a first set of grooves associated with said first set of segments and a second set of grooves associated respectively with said second set of segments.

7. Apparatus as claimed in claim 6, said scroll plates being rotatable through an arc of from 75* to 90* .

8. Apparatus as claimed in claim 6, said scroll plate being rotatable through an arc of from 80* to 82*.

9. Apparatus as claimed in claim 6, the radially outward portions of said grooves being equally distant from and extending along circular arcs concentrically about said axis, and the radially inward portions of said second set of grooves extending radially inwardLy with respect to the radially inward portions of said first set of grooves and extending along circular arcs concentric with said axis.

10. Apparatus as claimed in claim 6, each said scroll plate having gear means thereon, scroll drive means carried by said end bodies for driving engagement with each said gear means to effect rotation of said scroll plate.

11. Apparatus as claimed in claim 10, said scroll drive means comprising a plurality of pinion drive shafts extending parallel to said center shaft and rotatable about pinion axes spaced angularly thereabout, and a plurality of shell pinions mounted rotatably in the respectively associated end body, each being corotatable with and coaxially slidable along a respectively associated one of said drive shafts;

and means connected to said pinion drive shafts for effecting rotation thereof about said pinion axes.

12. Apparatus as claimed in claim 11, said means for effecting rotation of said pinion drive shafts comprising a plurality of drive pinions mounted on said center shaft each of said drive pinions being coupled coaxially with a respectively associated pinion drive shaft for corotation therewith.

13. Apparatus as claimed in claim 12, said means to effect rotation of said pinion drive shafts comprising a drive gear mounted for rotation coaxially of said center shaft annd drivingly meshed with each of said drive pinions.

14. In tire building apparatus for building a tire having therein a circumferentially inextensible belt;

a building drum comprising an expansible sleeve providing a continuous exterior surface for contiguously supporting said tire and terminating in radially fixed inwardly turned ends;

a hollow cylindrical center shaft disposed coaxially within said sleeve and extending axially outwardly of said ends;

a pair of rigid end bodies mounted coaxially and corotatably on said shaft for movement toward and away from each other, said ends being secured respectively to said bodies;

a plurality of rigid interior support segments mounted within said sleeve on each of said bodies for movement radially of the drum rotation axis and cooperable to provide in one condition of said drum firm continuous cylindrical support to said sleeve between said ends;

said plurality of support segments comprising a first set of greater arcuate width and a second set of lesser arcuate width disposed in alternating circumferential sequence about each of said end bodies; and

a plurality of cover plates each extending axially of the drum and overlying an opposed pair of said support segments including a first set of cover plates each having axially extending edge portions overlying the adjacent axially extending edges of the respectively circumferentially adjacent pairs of the second set of segments, and a second set of cover plates each having axially extending edge portions, the latter said edge portions each slidably interengaging the respectively associated pair of the second set of support segments, and radially inwardly of the corresponding edge portions of said first set of cover plates.

15. Apparatus as claimed in claim 14, each support segment of said second set comprising a parallel pair of slots extending axially of the drum, each of said second set of cover plates having respectively opposite edge portions turned inwardly and slidably engageable in the respectively associated slots of said second set of segments.

16. Apparatus as claimed in claim 15, each of said slots extending inwardly of the circumferential surface of the respectively associated segment at an acute angle with respect to an axial plane aligned with the slot, the slots of a pair thereof in each such segment being in opposing angular relation with respect to each other.

17. Apparatus as claimed in claim 16, including centering means in said drum cooperating with said cover plates to maintain the same disposed in fixed axial relation with said center shaft and the mid-circumferential plane of said drum during mOvement of said support segments.

18. Apparatus as claimed in claim 17, said centering means comprising a center body fixed symmetrically with respect to said mid-circumferential plane on said center shaft, a plurality of radially extending bores spaced angularly about said axis in said center body, a plurality of rods slidably disposed one in each of said bores, garterspring means disposed about the radially outward end portions of said rods to urge the same radially inwardly, and means securing each of said cover plates respectively to one of said rods.

19. Apparatus as claimed in claim 18, said sleeve comprising a radially expansible cylindrical tubular member of limited axial extensibility, said sleeve cooperating with said end bodies to define a deformable chamber, and means communicating with said chamber to supply compressed air therein to expand said sleeve into toroidal shape during movement of said end bodies toward each other.

20. In tire building apparatus for building a tire having therein a circumferentially inextensible belt;

a building drum comprising an expansible sleeve providing a surface for supporting said tire and terminating in radially fixed inwardly turned ends;

a shaft disposed coaxially within said sleeve and extending axially outwardly of said ends;

a pair of rigid annular integral end bodies mounted coaxially and corotatably on said shaft for movement toward and away from each other, said ends being secured in radially fixed relation respectively to said bodies;

a plurality of rigid interior support segments including a first set of greater arcuate width and a second set of lesser arcuate width disposed in alternating sequence circumferentially about each said end body and mounted within said sleeve on each of said bodies for movement radially of the drum rotation axis and cooperable to provide in one condition of said drum firm continuous cylindrical support to said sleeve between said ends; and

means for moving said segments radially, and gear means for actuating said means for moving, said gear means comprising a gear mounted coaxially on said shaft for rotation relative thereto, angular movement limiting means corotatable with said gear and stop means fixed eccentrically of the axis on said shaft, said limiting means and said stop means being cooperable to stop angular rotation of said gear relative to said shaft in clockwise and anticlockwise directions after an angular displacement of said means for moving said segments about said axis.

21. Apparatus as claimed in claim 20, said limiting means comprising a lug extending radially of said gear, said stop means comprising a stud projecting axially of an end face of said shaft, said lug having two radially disposed abutments spaced arcuately about said axis, each abutment engaging said stud to stop rotation of said gear in one rotational sense.

22. Apparatus as claimed in claim 21, said lug extending angularly between said two abutments to limit said rotation to an angle between 150* and 320*.

23. In tire building apparatus for building a tire having therein a circumferentially inextensible belt;

a building drum comprising an expansible sleeve providing a continuous exterior surface for contiguously supporting said tire and terminating in radially fixed inwardly turned ends;

a hollow cylindrical center shaft disposed coaxially within said sleeve and extending axially outwardly of said ends;

a pair of rigid end bodies mounted coaxially and corotatably on said shaft for movement toward and away from each other, said ends being secured respectively to said bodies;

a plurality of rigid interior support segments mounted within said sleeve on each of said bodies for movement radially of the drum rotation axis and cooperable to provide in one condition of said drum firm continuous cylindrical support to said sleeve between said ends; and

means for moving said segments radially including gear means for actuating said meaNs for moving, said gear means comprising a gear mounted coaxially on said center shaft for rotation relative thereto, said center shaft having means for securing the same coaxially and corotatably on a spindle, said gear means further including a gear mounted coaxially on said spindle for rotation relatively thereto and positive locating means for angularly corelating said gear on said shaft with said gear on said spindle at a single selected angular relation while mounting said shaft on said spindle.

24. Apparatus as claimed in claim 23, said positive locating means comprising a projection extending axially of one said gear and a conforming recess extending axially of the other said gear, the projection and the recess interengageable only in a single angular relation of the one and the other said gear.

25. Apparatus as claimed in claim 23, each said gear having the same number and form of teeth and being drivably engageable with a single additional gear.

26. In tire building apparatus for building a tire, a building drum comprising an expansible sleeve, terminating in radially fixed inwardly turned ends, a plurality of rigid interior support segments mounted within said sleeve for movement radially of the drum rotation axis and associated respectively with each of said ends, and a plurality of cover plates each overlying axially of the drum an opposed pair of said support segments including a first set of cover plates each having edge portions overlying the adjacent edges of the respectively circumferentially adjacent pairs of segments and a second set of cover plates each having edge portions, the latter said edge portions each slidably interengaging the respectively associated pair of said segments, and radially inwardly of the corresponding edge portions of said first set of cover plates.

27. Apparatus as claimed in claim 26, said plurality of support segments comprising a first set of greater arcuate width and a second set of lesser arcuate width disposed in alternating circumferential sequence about said axis, each support segment of said second set comprising an axially extending parallel pair of slots, each of said second set of cover plates having respectively opposite axially extending edge portions turned inwardly and slidably engageable in the respectively associated slots of said second set of segments.

28. Apparatus as claimed in claim 27, each of said slots extending inwardly of the circumferential surface of the respectively associated segment at an acute angle with respect to an axial plane aligned with the slot, the slots of such pair in each such segment being in opposing angular relation with respect to each other.