Glass sheet processing system having cooling of conveyor roller ends

Glass sheet processing system with cooling of conveyor roller stage

The present invention relates to a glass sheet processing system having a conveyor comprising rollers having roller stages that are cooled in the heated environment of the system.

Conventionally, glass sheets are formed by heating on a conveyor in a furnace and then molding in a heated chamber prior to transfer for cooling. Such cooling may be slow cooling to provide annealing, faster cooling to provide thermal strengthening, or rapid cooling to provide tempering. Regarding heating of glass sheets, US Patents: 3,806,312 McMaster et al; 3,947,242 McMaster et al; 3,994,711 McMaster; 4,404,011 McMaster; and 4,512,460 McMaster. With respect to glass sheet molding, U.S. Patents: 4,204,854 McMaster et al; 4,222,763 McMaster; 4,282,026 McMaster et al.; 4,437,871 McMaster et al.; 4,575,390 McMaster; 4,661,141 Nitschke et al.; 4,662,925 Thimons et al; 5,004,491 McMaster et al.; 5,330,550 Kuster et al; 5,376,158 Shetterly et al.; 5,472,470 Kormanyos et al; 5,900,034 Mumford et al.; 5,906,668 Mumford et al.; 5,925,162 Nitschke et al.; 6,032,491 Nitschke et al.; 6,173,587 Mumford et al.; 6,227,008 Shetterly; 6,418,754 Nitschke et al.; 6,543,255 Bennett et al.; 6,578,383 Bennett et al.; 6,718,798 Nitschke et al.; 6,729,160 Nitschke et al. With respect to cooling, US Patents: 3,936,291 McMaster; 4,470,838 McMaster et al; 4,525,193 McMaster et al.; 4,946,491 Barr; 5,385,786 Shetterly et al.; 5,917,107 Ducat et al.; 6,079,094 Ducat et al.; and 6,513,348 Bennett et al.

The rollers utilized to transport the glass sheet may contain sintered bonded fused silica that can operate without thermal bending upon heating to relatively high temperatures, which may normally exceed 600°C, which may be involved. However, such high temperature may cause bearing problems, and may also cause problems in the mounting of metal end caps used to support the rotating rollers.

<p>It is an object of the present invention to provide an improved high temperature glass sheet processing system.</p>

<p>In order to achieve the above object, a high-temperature glass sheet processing system having a structure according to the present invention is a set of rollers extending in a conveying direction of the processing system, positioned at a heated position of the system and aligned with each other along the conveying direction. and a roller conveyor having a plurality of rollers having stages. The machining system also includes a roller support structure having an elongate cooling unit including a housing positioned in a heated position of the system and defining a cooling chamber for receiving and having a bearing rotatably supporting an aligned set of roller stages. include The cooling unit includes a cooling circuit that supplies cooling fluid to the cooling chamber to provide cooling of the roller stages of the aligned set and cooling of the bearings.</p><p>As disclosed, the cooling circuit supplies a liquid that provides cooling of the aligned set of roller stages and bearings. The liquid used is water which provides cooling of the aligned set of roller stages and bearings, more specifically a mixture of water and antifreeze which provides cooling of the aligned set of roller stages and bearings.</p><p>The disclosed roller support structure further includes an air supply that prevents heated air from the processing system from flowing to the cooling unit to heat the aligned set of roller stages and bearings.</p><p>As also disclosed, the roller support structure includes a round can having respective open ends projecting into the cooling chamber and having an aligned set of roller ends each projecting into the cooling chamber. The round can supports a bearing that rotatably supports the aligned set of roller ends, and the round can having an open end and a housing of the cooling unit is a cooling circuit for supplying water for cooling the aligned set of roller ends and the bearings. Define the flow path.</p><p>The roller ends of the aligned set each have end caps fixed thereto, and the end caps each have support projections rotatably supported by bearings. The air supply also provides air into the round can to prevent heated air from the processing system from flowing into the cooling unit between the round can and the aligned set of roller ends to prevent heating of the end caps and bearings.</p><p>The objects, features and advantages of the present invention will become readily apparent from the detailed description of preferred embodiments given below with reference to the accompanying drawings.</p>

<p>By the glass sheet processing system with cooling of conveyor roller stages of the present invention, it is possible to provide rollers having roller stages that are cooled in the heated environment of the system.</p>

1 is a schematic plan view of a glass sheet processing system embodying the present invention. FIG. 2 is a schematic side view of the machining system along the line 2-2 in FIG. 1 ; FIG. 3 is a schematic elevational end view of a processing system along line 3-3 of FIG. 1, with first and second moldings having molding molds utilized to provide glass sheet molding within a heated environment of the system; and shows a forming station having a roller conveyor cooling unit of the present invention. FIG. 3A shows from the previous cycle, from the left first forming station to a position below and above the lower mold which has released a molded glass sheet onto a transfer mold to be subsequently moved out of the forming station for transfer; It is a partial elevation view showing the right second forming part of the forming station of FIG. 3 after the initial forming glass sheet has been moved onto the first upper mold. FIG. 3B is another partial view of the right second forming part of the forming station of FIG. 3 showing the glass sheet during press forming between the lower mold and the second upper mold; FIG. Figure 4 is a perspective view of the system housing with its top removed to show the cooling unit providing cooling of the conveyor roller stages in a heated position within the system housing; FIG. 5 is an elevation view along the line 5-5 of FIG. 4 further showing the cooling unit; FIG. 6 is a cross-sectional view taken along the line 6-6 of FIG. 5 further illustrating the structure of the cooling unit. FIG. 7 is a cross-sectional view passing through the cooling unit along the line 7-7 of FIG. 6 . Fig. 8 is a cross-sectional view generally taken along the line 8-8 of Fig. 7 with the roller end broken and the bearing removed to show the structure of each of the pair of bearing supports supporting the bearing rotatably supporting the associated roller end; .

As necessary, detailed embodiments of the present invention are disclosed herein, but it is to be understood that the disclosed embodiments are merely illustrative of the present invention that may be embodied in various and alternative forms. The drawings are not necessarily to scale, and some features may be exaggerated or minimized to show details of specific components. Accordingly, the specific structural and functional details disclosed herein are not to be construed as limiting, but merely as representative standards for teaching those skilled in the art to variously employ the present invention.

1 to 3 , a glass sheet processing system, generally designated 10, embodies the present invention, and comprises a furnace 12 and a forming station comprising first and second forming positions 16 and 18 ( 14), and a cooling station 20 for cooling the shaped glass sheet G with slow cooling for annealing, faster cooling for thermal strengthening, or more rapid cooling for tempering. The first forming section 16 of the heating furnace 12 and the forming station 14 includes a roller conveyor 22 having conveyor rollers 24 conveying the glass sheet G along the conveying direction C of the heating. include The roller 24 is made of sintered bonded fused silica particles to provide resistance to thermal warpage during heating and cooling to provide planarity of the glass sheet during transport. As schematically shown in FIG. 2 , all of the components of the machining system 10 are controlled by the controller 25 via a control bundle 25a of wire, optical fiber, tube, etc. FIG.

As shown in Fig. 3, each roller 24 has one end 26 that can extend outward of the furnace to be rotationally driven by a schematically shown drive mechanism 28, while the other end of each roller 24 30 is located in a heated position adjacent the junction 32 between the first and second portions 16 , 18 of the forming station 14 and received in the roller support structure 34 schematically shown in FIG. 3 . do. More specifically, the support structure 34 as shown in FIGS. 4 and 5 has an elongated shape along the conveying direction C and a bearing 42 rotatably supporting the aligned set of roller ends 30 . ) an elongate cooling unit 36 shown in FIG. 6 including a housing 38 defining a cooling chamber 40 containing and having. The cooling unit 42, best shown in FIG. 5, is a cooling chamber through which cooling fluid is supplied to provide cooling of the bearings 42 and cooling of the aligned set of roller stages 30 during operation of the system. It includes an inlet 44 and an outlet 46 .

In a specific processing system 10 as shown in FIG. 3 , the forming of the glass sheet is performed with conveyor roller stages 30 cooled within a support structure 34 , as will be more fully described below. More specifically, the system comprises a first forming having a first upper mold 48 comprising a downwardly opposed forming surface 50 that is curved along a conveying direction C but having a straight element with respect to a direction transverse to the conveying direction. a forming station 14 having a portion 16, a second forming portion 18 having a downwardly opposed forming surface 54 curved in a conveying direction C and transverse to the conveying direction C; It has a second upper mold (52). The actuator 55 has a roller 55a supporting a beam 56 (only one shown) on which the first upper mold 48 is supported and moved slightly vertically by actuation of the actuator 55 during the forming operation, An actuator 57 moves the beam 56 during the forming operation and moves the first upper mold 48 horizontally on the beam between the first and second forming portions 16 , 18 of the forming station 14 . The transverse roller 55b also contacts the beam 56 to provide transverse positioning during movement of the first upper mold 38 between its pickup position in FIG. 3 and its delivery position in FIG. 3A . .

Also, the actuator 58 vertically moves the second upper mold 52 during the forming cycle of the forming station 14, the first and the second to initially support and subsequently release the glass sheet G being formed. The pressurized air source 60 supplies the pressurized air to the first and second gases to provide vacuum and at other times pressurized air through the hole arrays in the forming surfaces 50 and 54 of the second upper molds 48 and 52. It is supplied to the pumps (61, 62). Further, in the second forming section 14 of the forming station, the lower mold 64 is supported for vertical movement by the jack 66 during forming. This vertical movement can be made downward to cause the first upper mold 38 to move over the lower mold 64, then release of the glass sheet more closely spaced relative to the lower mold to control positioning. This vertical movement can be made upwards to be made in a fixed relationship. Also, in order to perform press bending, the vertical movement of the lower mold 64 may be used in conjunction with the vertical movement of the second upper mold 52 . The gas jet pump array 70 also provides for the lift of the heated glass sheet G from the roller conveyor 22 to the first upper mold 48 to initiate the forming cycle as described below.

In addition to the forming station 14 , the system 10 as shown in FIG. 3 includes a cooling station 20 , in which the molded glass sheet G is transferred to an actuator 76 on the transfer mold 74 for cooling. from the second forming section 18 to the cooling station between the lower and upper quenching heads 78 to the cooling station 20 . Also, as noted above, this cooling may be slow cooling for annealing, more rapid cooling for thermal strengthening, or rapid cooling for tempering.

The forming station 14 shown in FIGS. 3 , 3A and 3B is a first upper mold 48 in which the glass sheet has a curvature in a first direction and a straight element in a second direction transverse to the first direction. After being molded on the upper mold and received from the first upper mold 48 in its delivery position shown in FIG. 3A, it is then gravity molded laterally on the lower mold 64, having an open center ring shape, and finally, As shown in FIG. 3B , it has a three-step operation in which it is formed by press molding between the second upper mold 52 and the lower mold 64 .

Referring to FIG. 3 , the glass sheet G is lifted from the roller conveyor 22 by the vacuum applied to the surface 50 of the first upper mold 48 and the upward gas flow from the gas jet pump array 70 . The operating cycle of the forming station 14 is initiated by the downward movement of the first upper mold 48 in the left first forming section 16 . More specifically, the first upper mold 48 may be moved down about 1/2 inch (12-15 mm) from the conveyor 22 by an actuator 55 for initial pickup of the glass sheet, such that Next, the first upper mold 48 may be moved upward so that the first upper mold can be moved to the upper part of the support structure 34 . The actuator 57 is then placed in the position shown in FIG. 3A above the lower mold 64 and below the raised upper mold 52 shown on top of the transfer mold 74 which is still running in the preceding cycle. Move the beam 56 and the first upper mold 48 to the right into the second forming section 18 of the furnace forming station. Simultaneous positioning of the first upper mold 48 and the transfer mold 74 at different elevations within the second mold 18 reduces system cycle time to provide greater output and advantageously the final molded glass It provides an overlapping cycle that reduces the cost of sheet products.

After the lower mold 64 receives the glass sheet, in order to prepare for the next cycle, as shown in FIG. 3 , the first upper mold 48 moves back to the first molding part 16 , and the glass The sheet G is press-formed between the second upper mold 52 and the lower mold 64 , as shown in FIG. 3B . Subsequently, the second upper mold 52 is moved upward to the position of FIG. 3A with the press-formed glass sheet supported thereby, and the transfer mold 74 is followed by the quenching 20 shown in FIG. 3 . It is moved into the second forming section 14 shown to receive the press-formed glass sheet for further movement.

It should be understood that the support structure 34 and its cooling unit 36 may also be used in other systems having a heated position, in addition to the disclosed forming stations where the support structure and cooling unit have particular practicality. For example, forming station 14 may alternatively be a first upper mold moving only vertically, as disclosed in US Patent Application Publication No. US 2015/0218029 A1, the disclosure of which is incorporated herein by reference in its entirety. and a lower mold that horizontally moves from below the first upper mold to the second upper mold at an altitude below the elevation of the transfer mold that delivers the molded glass sheet after press molding between the lower mold and the second upper mold have.

In a preferred configuration of the cooling unit 36 , a cooling circuit is provided to the cooling chamber 40 shown in FIG. 6 and the inlet 44 and outlet 46 shown in FIG. 5 . The fluid, preferably provided as a liquid flowing through the circuit, is cooled by the roller ends 30 of the aligned set of conveyor rollers 24 and associated bearings 42, as shown in FIGS. 6 and 7 . provides cooling. As more specifically disclosed, to provide cooling of the aligned set of roller stages 30 and bearings 42, water is the liquid utilized, preferably as a mixture of water and antifreeze. After passing through the system, the antifreeze prevents freezing due to cooling in an external cooler, and also prevents the accumulation of deposits in the cooling circuit by the antifreeze additive.

5 and 6 , the roller support structure 34 prevents the heated air of the machining system from flowing into the cooling unit 36 to heat the aligned set of roller stages 30 and bearings 42 . It includes an air supply, generally designated 80, to prevent it. More specifically, the roller support structure 34 protrudes inwardly from the housing 38 , with an aligned set of roller ends 30 having respective open ends 84 protruding inwardly into the cooling chamber 40 . with a round can 82 . A round can 82 supports bearings 42 that rotatably support an aligned set of roller ends 30 , a housing 38 of a cooling unit 36 and a round can having an open end as shown in FIG. 5 . The flow path of the cooling circuit that flows from the inlet 44 to the outlet 46 as described above with reference to supplying water to cool the aligned set of roller stages and bearings is defined.

As shown in FIG. 6 , the roller ends 30 of the aligned set each have end caps 86 secured to the sintered bonded fused silica of their associated rollers, each end cap secured thereto by retainers 90 . It has a projection 88 accommodated in the inner ring of the anti-friction bearing 42 . The high temperature adhesive fixes the end cap 86 to the roller end 30 , both of which are cooled by water circulating through the cooling chamber 40 , while being cooled from the air supply 80 . The air flow of the duct prevents hot air from the inside of the machining system from heating these parts. The air supply unit 80 as shown supplies pressurized air to the supply tube 94 and eventually supplies the pressurized air to the tube 100 supporting the round can 82 and supplies the pressurized air into the round can. and a source of pressurized air 92 ( FIG. 5 ) that supplies pressurized air to a branch tube 96 connected to a fitting 98 .

7 and 8 , the bearing seat 102 inside each round can 82 supports the anti-friction bearing 42 on the outer ring of the anti-friction bearing 42 , so that the anti-friction bearing 42 is placed on the end cap 86 . The protrusion 88 provides rotatable support for the roller end 30 received in the inner ring of the bearing.

For a more specific disclosure of the delivery device 69, reference is made to the U.S. patent application filed concurrently under the name LIFT DEVICE FOR A GLASS PROCESSING SYSTEM, the U.S. patent application with directory number GLT 1993 PUS, the entire disclosure of which is incorporated herein by reference. .

Although exemplary embodiments are described above, they are not intended to describe all possible forms of the invention. Rather, the terms used in the specification are for the purpose of description and not limitation, and it is understood that various changes may be made without departing from the spirit and scope of the present invention. In addition, features of various embodiments can be combined to form further embodiments of the invention.