Two drum turret for tire assembly

Abstract: A turret (22) for a tire building system having two drums (26,49) with drum shafts (30,42) mounted on the turret and adjusted so that the axes of the drums will be offset and parallel providing a compact turret assembly with a minimum shaft length and weight. The offset drum shafts provide for positioning of the drums in operating positions of different heights (50,52) relative to the floor surface (12) so that manual operations can be carried out at the lower drum position where there is easy access by an operator. Safety provisions (74) are incorporated to disengage the motor (63) and stop rotation of the turret if the motor does not stop and thereby protect the operator and the turret mechanism.

Description: Turrets having two drums have been designed for tire building machines heretofore to provide for the assembly of tire components and performing other tire building operations at two different positions. Where the drums have been rotated 180 degrees from a first position to a second position a deep pit has been required in the floor so that the drums will be at a suitable height above the floor for performing manual tire assembly operations. When the drum shafts have been coaxial a reinforced turret construction has been required to support the weight of the drums to be carried at substantial distances from the axis of rotation of the turret determined by the length of the drum shafts. This is shown in EP-A- 0 242 689. Heretofore, rotation of the turret, including the drums and ancillary equipment has been stopped when the actuating motor has been stopped. The turret was then locked in position by braking grips urged into engagement with slots in a disc connected to the shaft rotating the turret. No provisions were made for disengaging the turret from the motor to stop the turret if the motor does not stop. This is important when the turret rotary parts may weigh as much as 6,000 pounds (2,720 kg). SU-A- 682 389 discloses a tire assembly line having a first drum for mounting the carcass and the beads. The drum is then swung around to align with a second drum where the tread is assembled opposite the first drum and offset in height relative to the first drum axis. The rotation takes place in a vertical plane round an axis lying on a level between the axes of the two assembly drums. In accordance with the present invention, a two drum turret is provided having drums rotatable about offset parallel axes as defined in the appended claims. With this construction the length of the shafts supporting the drums is minimized so that a compact turret of minimum weight may be used to support the drums. Also the offset drums provide for positioning one of the drums at a height lower than the other drum which is desirable for operator access to the drum in the lower position. Safety features are also incorporated in that if there is overtravel of the turret, the motor drive pinion will be disengaged from the semi-circular gear rack and movement of the turret will be stopped by a shock absorber. With the offset axis two drum turret of this invention, the depth of the pit in the floor is minimized and different height working positions of the drums are made possible for increased efficiency. In the Drawings Fig. 1 is a front elevation of a two drum turret assembly embodying the invention. Fig. 2 is a side elevation of the turret assembly taken along line 2-2 in Fig. 1 with the drums removed. Fig. 3 is a rear elevation of the turret assembly taken along line 3-3 in Fig. 2 with parts being broken away. Fig. 4 is fragmentary top view of the turret taken along line 4-4 in Fig. 1. With reference to Figs. 1, 2 and 3 a base 10 is shown mounted on a floor surface 12 and fastened to a turret support housing 14 by bolts 16 or other suitable fasteners. Pillow blocks 18 are mounted on the housing 14 providing bearings for supporting a turret drive shaft 20. A turret 22 is mounted on one end of the shaft 20 and includes a turret supporting plate 24. Referring to Figs. 1 and 4 a first drum 26 is rotatably mounted on the turret supporting plate 24 and extends outwardly from a first side 28 of the turret 22 for rotation about an axis A-A in a first position X. The first drum 26 is also known as a slave drum and is mounted on a slave shaft 30 rotatably supported in a slave bearing 32 mounted on the supporting plate 24. A slave drum drive motor 34 is also mounted on the supporting plate 24 and is in a driving relationship with the slave shaft 30 through a slave belt 36 extending around pulleys mounted on the slave shaft 30 and shaft of the slave drum drive motor 34. Mounted on the second side 38 of the turret 22 is a second tire building drum 40 rotatable about a second axis B-B in a second position Y. The second tire building drum 40 which is also known as the master drum is mounted on a master shaft 42 supported in a master bearing 44 mounted on the supporting plate 24. The master shaft is driven by a master drum drive motor 46 mounted on the supporting plate 24 and connected by a master belt 48 to the master shaft through drive pulleys. As shown in Fig. 1 the axis A-A of the first drum 26 and the axis B-B of the second drum 40 are in parallel relationship so that in the operating position the first drum 26 is at a first height 50 of about 40 inches (101.6 cm) above the floor surface 12 which is less than a second height 52 of about 50 inches (127 cm) of the second drum 40 above the floor surface. This is important in that when manual operations for applying the tire components to the drum 26 are required the drums 26 and 40 need to be close to the floor surface 12 in order that the operator can reach the drums. In addition to the axes A-A and B-B being parallel the turret construction provides for offsetting of the slave shaft 30 from the master shaft 42 which minimizes the distance the first drum 26 and second drum 24 extend outwardly from the first side 28 and second side 38 of the turret. This configuration reduces the space required for rotation of the turret 22 and the depth of a pit 54 necessary to permit rotation of the turret about the axis of the turret drive shaft 20. It is important for effective operation of the two drum turret assembly of this invention that the first drum 26 and second drum 40 have axes A-A and B-B which are symmetrical about axis C-C of the turret driveshaft 20. In accordance with the invention the master bearing 44 is mounted on the supporting plate 24 in a predetermined position. This is accomplished by urging the edges of the master bearing 44 against registers 55 and 56 on plate 24 with adjusting screws 57 threaded in the plate. Then the position of the slave bearing 32 is adjusted by adjusting screws 58 and 59 threaded on the plate 24 so that the axis A-A of the first drum 26 is parallel with axis B-B of the second drum 40 as well as being symmetrical about axis C-C of the turret drive shaft 20. With this adjustment the first drum 26 and second drum 40 will be in identical positions when the first position X and the second position Y so that tire components applied to the drums are applied in identical positions regardless of which drum is in a particular position. Referring to Figs. 2 and 3 a drive gear 60 is mounted on the rear end of the turret drive shaft 20. The drive gear 60 has a semi-circular gear rack 61 engageable by a pinion gear 62 driven by a turret drive motor 63 mounted on the housing 14. Referring to Fig. 3 the drive gear 60 is rotated from the position shown in Fig. 3 in a clockwise direction 180° so that the turret supporting plate 24 as shown in Fig. 1 will rotate 180° in a counter clockwise direction moving the first drum 26 from the first position X shown in Fig. 1 to the second position Y shown in Fig. 1 and moving the second drum 40 from the second position Y shown in Fig. 1 to the first position X shown in Fig. 1. In the two operating positions X and Y a cam roller 64 actuated by a pneumatic lock 66 extends into a tapered slot 68 or slot 70 at the operating positions of the turret 22 to lock the turret in an operating position. In the event the motor 63 does not stop to permit actuation of the cam roller 64 by the pneumatic lock 66 the length of the semi-circular gear rack 61 is predetermined for disengaging the pinion 60 whereupon the shaft 20 will continue to rotate and arm 72 mounted on the shaft and extending outwardly therefrom is positioned to engage shock absorbers 74 mounted on the housing 14. One of the shock absorbers 74 is provided at each side of the housing 14 to limit the rotation of the turret supporting plate 24 in either direction by engagement with the arm 72. In a typical tire building operation tire components may be applied to the first drum 26 and the second drum 40 by rotating the drums through actuation of the slave drum drive motor 34 and master drum drive motor 36 in response to suitable controls connected to the motors. After application of the tire components the cam roller 64 may be released and the turret drive motor 63 actuated in response to suitable controls for rotating the turret 22 180° whereby the first drum 26 is moved to the second position Y and the second drum 40 is moved to the first position X as shown in Fig. 1. Simultaneously with the application of additional tire components on the first drum 26 in the second position Y at the second height 52 tire components may be provided on the second tire building drum 40 in the first position X as shown in Fig. 1. It is understood that the first drum 26 and second drum 40 are identical however drums of different sizes and types may be substituted for these drums and be adaptable for different tire building operations. While a certain representative embodiment and details have been shown for the purpose of illustrating the invention it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the scope of the invention.

Claims: A tire building apparatus comprising a turret (22) rotatable about a turret axis (C-C), a first drum (26) extending outwardly from a first side (28) of said turret (22) and rotatable about a first axis (A-A), a second drum (40) extending outwardly from a second side (38) of said turret (22) being rotatable about a second axis (B-B) parallel to and spaced from said first axis (A-A) and means to rotate said turret (22) to move said first drum (26) from a first position (A) at a first height (50) to a second position (B) at a second height (52) and move said second drum (40) from said second position (B) to said first position (A) providing access to said first drum (26) and said second drum (40) by an operator at said first height (50) for tire component applications at a lower height above a floor surface (12) characterized by said means to rotate said turret (22) including turret power means (63) to rotate said turret (22) a predetermined angular distance, safety release means (61) to disengage said turret power means (62) after rotation of said turret said angular distance, and motion limiting means (74) to stop rotation of said turret (22) after rotation of said turret (22) beyond said predetermined angular distance. The tire building apparatus of claim 1 further characterized by said first drum (26) having a first shaft (30) rotatably mounted on said turret (22) and rotatable about said first axis (A-A) and said second drum (40) having a second shaft (42) rotatably mounted on said turret (22) and rotatable about said second axis (B-B). The tire building apparatus of claim 2 further characterized by said first shaft (30) being offset from said second shaft (42) to minimize the distance said first drum (26) and said second drum (40) extend outwardly from said first side (28) of said turret and said second side (40) of said turret (40) thereby minimizing the weight of said turret (22) and the space required for rotation of said turret (22) including said first drum (26) and said second drum (40). The tire building apparatus of claim 1 further characterized by said first axis (A-A) and said second axis (B-B) of said first drum (26) and said second drum (40) being horizontal in said first position (X) and said second position (Y) for application of tire components. The tire building apparatus of claim 1 further characterized by safety release means (61) comprising a motor (63) having a pinion gear (62) engageable with a semi-circular gear rack (61) on said turret (22) movable out of engagement with said pinion gear (62) after said turret (22) is rotated said predetermined angular distance.

Inventors: CONGER KENNETH DEAN, TESTA DEAN CHARLES, CONGER, KENNETH DEAN, TESTA, DEAN CHARLES
Applicants: GOODYEAR TIRE & RUBBER, THE GOODYEAR TIRE & RUBBER COMPANY
Application year: 1997
Main classification: B29D30
IPC codes: B29D30