Segmented tire mold apparatus

Claim 2

Apparatus for molding a tire comprising a first annular sidewall mold part, a second annular sidewall mold part movable coaxially of the mold axis relatively of said first part, a plurality of tread mold segments mounted on said first sidewall mold part, and closing means connected to and axially movable relatively of said second part and engageable with means carried by said segments to move the segments only radially inwardly in response to said axial movement of said closing means, said segments being mounted for limited inward and for free and unlimited radiallY outward movement and removal from said first sidewall mold part in a plane parallel to said first part sidewall mold, and tread segment opening means engageable with said segments and mounted independently of and apart from said closing means for rotation in a plane normal to said axis and in non-interfering relation with the removal of said segments.

Claim 3

Apparatus as claimed in claim 1, wherein said opening means comprises camming means engageable with follower means fixed with respect to each said tread mold segment and movable relatively of said follower means to effect radially outward movement of said segments.

Claim 4

Apparatus according to claim 2, said camming means comprising a cam ring mounted inwardly of said follower means for rotation coaxially of the said first mold part, said ring having a plurality of cam ramps each associated respectively with one of said follower means and engageable with the latter to move said segments only outwardly.

Claim 5

Apparatus as claimed in claim 2, including means for actuating said camming means.

Claim 6

Apparatus as claimed in claim 4, said means for actuating said camming means comprising a fluid cylinder operable to effect partial rotation of said camming means.

Claim 7

Apparatus as claimed in claim 4, said means for actuating said camming means comprising a stud mounted fixedly relative to one of said second part and said camming means, a cam plate having a helical slot mounted fixedly with respect to the other of said second part and said camming means, said stud being engageable in said slot and movable therein response to movement of said second part coaxially of said first part to effect rotary movement of said camming means.

Claim 8

Apparatus as claimed in claim 4, comprising a cam drive plate mounted coaxially and rotatably relative to said cam ring, a spring-biased pawl pivotally mounted on said cam drive plate, said cam ring having a plurality of notches successively engageable with said pawl to effect corotation of said cam ring and said cam plate in a first rotational sense, said pawl being disengageable from said cam ring during rotational movement of said cam drive plate in the opposite rotational sense, and said actuating means including means for effecting rotation of said cam drive plate in response to coaxial relative movement between the first and second parts of said mold.

Claim 9

Apparatus as claimed in claim 1, said first annular mold part including a changeable upper sidewall mold, said second annular mold part including a changeable lower sidewall mold, the pair oF sidewall molds being disposed coaxially along a common axis, support means for supporting the lower sidewall mold with said axis extending vertically, means mounting the upper sidewall mold for movement toward and away from the lower sidewall mold, the plurality of said tread mold segments being arranged about said common axis, mounting means carried by said support means for mounting said tread segments interchangeably and for movement radially of said axis, said closing means being movable in the direction of said axis and engageable with means movable with said tread mold segments to move said segments toward said axis in response to downward movement of said closing means, and said opening means including camming means carried by said support means for rotation about said axis and engageable with cam follower means movable with said segments to move said segments radially only outwardly of said axis, said mounting means permitting unlimited movement of said segments radially outwardly of said axis.

Claim 10

Apparatus as claimed in claim 1, comprising bolster means cooperatively associated with said second mold part to effect movement thereof coaxially toWard and away from the first mold part.

Claim 11

Apparatus as claimed in claim 9, said closing means being mounted on said bolster means and cooperatively engageable with means on said tread mold segments to move the same radially only inwardly.

Claim 12

Apparatus as claimed in claim 1, comprising guide means associated with said first part and extending radially outwardly therein, and slide means secured one on each of said tread mold segments to slide in said guide means, said guide means being open at the radially outward ends thereof to permit free removal therefrom of said tread mold segments, said guide means and said slide means cooperating to prevent any significant movement of the tread mold segments axially with respect to the first mold part.

Claim 13

Apparatus as claimed in claim 11, said guide means comprising a plurality of T-slots extending radially inwardly from the periphery of said first part, said slide means comprising a slide block affixed one each on said segments and slidable in said respective T-slots, each said slide block having a crossbar portion slidable in the respective T-slot to limit relative movement between said segment and said first part in the axial direction, said crossbar portion extending radially inwardly of the outward end of the respective slide block a minor fraction of the length of said slide block, whereby each said segment is released from said T-slot for upward movement away from the first mold part after radial movement outwardly beyond the normal operating travel thereof.

Claim 14

Apparatus in accordance with claim 11, said guide means comprising a plurality of T-slots each associated with a respective one of said thread mold segments, and said slide means comprising a plurality of T-blocks each secured on one of said tread mold segments.

Claim 15

Apparatus as claimed in claim 13, said opening means including a cam follower mounted on each of said T-blocks, and camming means having a plurality of cam ramps each disposed radially inwardly of and engageable with a respective one cam follower.

Claim 16

Apparatus in accordance with claim 13, comprising means defining an annular channel disposed coaxially of said first part, means defining an opening between said channel and each of said T-slots, said opening means comprising camming means including a cam ring mounted in said channel for rotation coaxially of said first part, said cam ring having a plurality of cam ramps, a cam follower mounted on each of said tread mold segments and extending through said opening, each said cam follower being cooperable with the respective one of said cam ramps to move the respectively associated tread mold segment radially outwardly with respect to said cam ring in response to a rotational movement of said cam ring.

Claim 17

Apparatus as claimed in claim 15, said closing means comprising a closiNg ring having a frusto-conical inward surface cooperable with conforming outward surfaces of said tread mold segments.

Claim 18

Apparatus as claimed in claim 16, said first annular mold part comprising a lower sidewall mold oriented upwardly to receive a tire thereon, said closing means comprising a closing ring freely separable from said tread mold segments during axial upward movement of said closing ring and said second mold part away from said first mold part.

Claim 19

Apparatus as claimed in claim 1, further comprising control means to delay engagement of said second mold part with respect to said segments during closing of the mold until said closing means engages said means on said segments to initiate radially inward movement thereof.

Claim 20

Apparatus as claimed in claim 18, said control means comprising positive stop means for limiting the relative movement of said second part with respect to said closing means.

Claim 21

Apparatus as claimed in claim 19, said positiVe stop means comprising a plurality of bolts, a press bolster mounting said closing means for movement axially of said mold, said bolts being rigidly affixed to said second part in spaced circular array concentric with said axis and extending parallel thereto, and flange means on said bolts engageable with means carried by said bolster to limit positively the movement of said first part away from said bolster.

Claim 22

Apparatus as claimed in claim 1, said opening means comprising an integral annular cam housing ring, means for mounting said cam housing ring on a conventional press bottom platen, said ring being composed of a metal differing from the metal of said segments.

Claim 23

Apparatus as claimed in claim 21, said cam housing ring having means thereon for locating said first mold part concentrically with said axis.

Claim 24

Apparatus as claimed in claim 22, said housing ring comprising means defining an annular channel disposed coaxially of said first part, a plurality of T-slots each extending radially inwardly of the periphery of said first part and aligned respectively with said segments, means defining an opening between said channel and each of said T-slots, said opening means further comprising camming means including a cam ring mounted in said channel for rotation coaxially of said first part, said cam ring having a plurality of cam ramps, a cam follower mounted on each of said tread mold segments to extend through said opening, each said cam follower being cooperable with the respective one of said cam ramps to move the respectively associated tread mold segment radially outwardly with respect to said cam ring in response to a rotational movement of said cam ring.

Claim 25

Apparatus as claimed in claim 21, said cam housing ring having register means cooperable with means on a press lower platen to register said housing ring coaxially of the mold axis.

Claim 26

Apparatus as claimed in claim 24, said register means comprising an annular flange cooperable with an annular rabbet formed on said platen.