US1947408A - Method of and apparatus for annealing glassware - Google Patents

Description

Feb. 13, 1934. H. l.. EASTMAN METHOD OYF AND APPARATUS FOR ANNEALING GLASSWARE Filed Feb. l1, 1932 ZZlo egys Q m. Q\ mlbw m1 .i w @y u I Il m w Al l( J l l i inl. m Q w E.. l l In .hwl E y L! llll lOl i In n.

MM MN Patented Feb. 13, 1934 UNITED STATES RIETHOD OF AND APPARATUS FOR ANN EALING GLASSWARE Harold L. Eastman, Hartford, Conn., assignor to Hartford-Empire Company, Hartford, Conn., a corporation of Delaware Application February 11, 1932. Serial No. 592,340

2 Claims.

This invention relates to a method of and apparatus for the annealing of glassware, and particularly to a method of and apparatus for annealing glassware wherein it is desired to effect accurate control of the temperature gradient of the ware adjacent to the entrance end of an annealing lehr in order to precondition it and bring it to the desired temperature for subsequent annealing.

Among the objects of my present invention is the provision of a method and apparatus in glassware annealing for controlling the `temperature in a zone of a glass annealing lehr adjacent to the ware-entering end thereof, whereby these temperatures may be made such as to supply heat to or abstract heat from ware entering the lehr, and particularly to'adapt such method and apparatus to use with a minimum change in design of combustion heated lehrs.

A further and more specific object of my invention is to provide in connection with4 a glassware annealing lehr, a longitudinally extending flue adjacent to the forward or ware-receiving end thereof and preferably located in the roof of the tunnel, in which flue there is `at least one zone through which heated gases or cooling air may be conducted alternatively, according as it is desired, to heat or cool glassware entering the lehr.

More particularly it is desired in connection with the attainment of this object that the temperature gradient in this flue be always upward along the path of movement of the ware.

A further object of the invention is to provide in a combustion heated glass annealing lehr, a muffle flue in heat transferring relation with the ware in the tunnel to which heated gases are supplied at a point spaced from the ware-entering end of the lehr and in connection with which means are provided for controlling the tempera.

ture gradient in separate but adjacent zones of the flue between the ware-entering end of the tunnel and the point of supply of heatedggases thereto, in order to provide a controlled temperature gradient in this flue and in the tunnel in response thereto.

Further objects and advantages of my present invention will become apparent from a reading of the following specification and sub-joined claims when taken in connection with the accompanying drawing, in which:

Figure 1 is a somewhat diagrammatic central vertical sectional view through a lehr embodying my invention; and

Fig. 2 is a fragmentary view, similar to Fig. 1, showing the left-hand end thereof on an enlarged scale.

In the accompanying drawing there is shownv a lehr comprising a tunnel 1 built up of a plurality of independent sections 2 forming a tunnel lining, these sections being of cast iron or other suitable material and being secured together in any desired manner. The tunnel lining is shown surrounded by suitable pulverulent heat insulating material 3 as kieselguhr or the like, the whole being surrounded and confined by a suitable casing 4 which may be of sheet metal. As shown, the tunnel l is anchored at its left-hand endas seen in the drawing, the ware-receiving end, by being secured at such end to suitable supports, the remainder of the tunnel being permitted to expand freely from this end and being supported for this purpose upon wheels 5 resting upon rails 6 which are supported upon suitable standards 7.

Ware is conveyed through the tunnel 1 by an slack take-up device 10 and thence forwardly beneath the tunnel, passingover a plurality of spaced rollers 11 suitably mounted upon the supports 7. At the forward end of the tunnel, the conveyor 8 passes around the rolls 12 and 13. The conveyor is preferably of open work metallic construction, as for example woven Wire.

Means are provided for controlling the temperatures in the tunnel from beneath, including a re box generally indicated at 14 into which a flame is projected from a suitable burner, as the burner 15, to which gas or oil is conducted through a pipe 16 controlled by a valve 17 or other suitable means. The products of combustion in the fire box 14 are preferably diluted in order to reduce and regulate their temperature to the desired point prior to their entry into the ue or flues 18, which pass longitudinally beneath the tunnel 1 and have as their top wall the floor of the tunnel. Such diluted air is preferably admitted to the fire box 14 through a damper controlled opening 19 (the damper not being shown in the accompanying drawing). The flue or flues 18 communicate through saddle pipes, indicated in dotted lines at 20 (Fig. 1), with a wind box 21 communicating with an exhaust fan 22 which is driven by a suitable means, as the motor 23, so that the flue or flues 18 are always at sub-atmospheric pressure due to the continuousl action of the fan 22. Means are provided for controlling the temperature gradient in the flue or flues 18, comprising a plurality of spaced air inlet openings 24 each controlled by a damper 25, so that the desired amount of atmospheric air may be drawn into the ue or flues 18 at intervals along its length for the purpose of diluting or cooling the gases therein and thereby controlling the temperature gradient in the flue or nues 18 and hence in corresponding portions of the tunnel 1. Ihe end of the flue or nues 18 adjacent to the exit end of the lehr communicates with the atmosphere through an inlet passage 26 similar to the passages 24 and controlled by a damper 27, so that cooling air may be drawn into the ue or fiues 18 at this point, passed forwardly to the saddle pipes 20 and thence being removed through the wind box 21 by the fan 22.

In the latter or cooling portion of the tunnel there are also provided in the roof one or more longitudinally extending cooling flues 28 communieating with the atmosphere at the exit end of the tunnel, as indicated at 29, and provided with a plurality of dampered take-off passages 30 communicating with a take-off conduit 31 which extends longitudinally of the lehr and communicates with the wind box 21 and the exhaust fan 22. Thus, it will be seen that atmospheric air in the desired amount can be drawn in a direction countercurrent to the movement of the ware, but in heat transferring relation therewith, through the flue or nues 28, suiicient air being withdrawn at intervals to control the temperature gradient in the flue or ues 28 and thus control the temperature gradient of the ware in corresponding portions of the tunnel 1. The cooling flue or flues 28 terminate at a stop 32 (Fig. 1) All the structure thus far described is disclosed inthe Mulholland Patent 1,560,481 granted Nov. 3, 1925 and per se forms no part of my present invention.

As indicated in the accompanying drawing, there are one or more flues 33 which extend longitudinally along the roof of the tunnel in prolongation of the flue or flues 28, but which do not communicate therewith due to the stop 32. Intermediate the ends of the flues 33 is a re box 34 communicating therewith through a passage 35. The fire box 34 is provided with a burner opening 36 into which is directed a uid fuel burner (not shown). Means including a dampered air inlet opening 37 (the damper not being illustrated) are provided for diluting and cooling to a desired degree the products of combustion in the re box 34 prior to their being supplied to the flue or fiues 33. In this way gases of the desired temperature may be supplied from the fire box 34 to the flue or ues 33.

The end or ends of the ue or fiues 33 toward the rear end of the tunnel and adjacent to the stop 32 communicate through an outlet passage 38 with the longitudinal take-off conduit 31, the amount of gases passing-from the fire box 34 along the flue or lues 33 in this direction being controlled by a damper 39 in the take-off passage 38.

Between the connection 35 and the forward or ware-entering end of the tunnel the flue or ues 33 are provided with a plurality (here shown as two) of passages 40 communicating with the flue or ues 33 at their lower ends and with a takeolf conduit 41 at their upper ends. The conduit 41 communicates through a suitable connecting passage 42 with the take-olf conduit 31, which in turn communicates with the wind box 21 and the fan 22.

As illustrated there are provided in the flue or flues 33 intermediate the connection 35 of the re box 34 and the nearest of the take-off ducts 40, a damper 43 to control the amount of heated gases from the fire box 34 passing forwardly along the flue or flues 33. Each of the passages 40 with the exception of the one nearest the entrance end of the lehr is provided with a suitable damper 44, and the take-off duct 41 is provided with a suitable damper 45 adjacent to its communication with the passage 40 nearest the ware-entering end of the lehr, so that desirable amounts of the products of combustion from the fire box 34 and passing forwardly may be withdrawn at intervals, whereby to control the temperature gradient in the forward end of the lehr. The paths of these gases are shown bythe full line arrows, and as shown a part of them pass out through the passage 40 intermediate the fire box 34 and the forward end of the lehr and another part pass through the duct 40 adjacent to the forward end of the lehr. These proportions are controllable by adjusting the positions of dampers 44 and 45. In this way it is possible to provide a controlled increasing temperature gradient along the path of movement of the ware adjacent to the entrance end of the tunnel.

In order that ware arriving at the lehr at temperatures higher than that desired for annealing may be suitably cooled to the desired temperature, I provide for the passage of cooling air in heat transferring relation with the ware through a predetermined rone adjacent to the ware-entering end of the lehr. For this purpose the duct 41 is open at its forward end to the atmosphere, as illustrated at 46, this opening being controlled by a suitable damper 47. Thus by closing the dampers 43 and 45 and opening the dampers 47 and 44 to the desired extent, cooling air may pass into the flue or flues 33 through the pas-sage 40 adjacent to the forward or ware-receiving'end of the lehr and pass out from these flues into the take-off duct 41 through any of the other passages 40 under control of the dampers 44. As shown in the accompanying drawing, only one of these intermediate passages 40 is illustrated, but it will be understood that as many as desired may be provided. The path of the cooling air is shown by the dotted line arrows in the accompanying drawing, although the position of the dampers as shown in this drawing is such that no cooling air would pass. Furthermore, if a plurality of ducts 40 were provided intermediate the ware-entering end of the lehr and the fire box 34, controllable proportions of this cooling air could be withdrawn through these several ducts. At any event the temperature gradient lwill be upward in the flue or lues 33 along the path of movement of the ware as the air is progressively heated in its movement parallel with the ware. Thus the greatest cooling of the ware will occur immediately adjacent to the entering end of the lehr. Likewise if more than two passages 40 were provided, any desired one, other than the one adjacent to the wareentering end of the lehr, could be used to admit cooling air to the flue or nues 33, and the last one used for removal of such cooling air by suitable regulation of the dampers provided in each passage 40. All possible combinations of structure shown or suggested by the foregoing are contemplated by the present invention.

Another possible method of control is that of opening the damper 47 part way and thus admitting some cooling air therethrough, while maintaining the damper 45 closed, thus causing cooling air to pass into the ue or ues 33 through the forward passage 40, also opening the damper 43 to some extent causing a portion of the gases from the lire box 34 to move forwardly in the tunnel, and withdrawing both the heating and cooling media through the one or more take-01T ducts 40 intermediate the first one used as the entrance for cooling air and the fire box 34 by suitable control of the dampers 44 therein.

When the upper cooling ues 33 are used for the purpose of reducing the temperature of ware entering the tunnel to the desired annealing temperature, it is preferable that there be no additional heat supplied through the lower cooling flue or flues 18. In this event sunicient air is admitted through the dampered opening 19 so that the gases admitted to the flue or iiues 18 are preferably at a temperature slightly below that of the ware entering the tunnel. Thus, any heat transmitted between the ware and these gases will pass from the ware to the gases. At the same time, by maintaining this temperature but slightly below that of the ware entering the tunnel, it may be maintained hot enough to control the temperature of the ware for the desired annealing, that is for the release of permanent strains therefrom and subsequently forcontrolling the rate of cooling of the ware. Also by suitably controlling the amount of gases passing forwardly and rearwardly from the fire box 34 through the ue or flues 33, the desired temperature gradient may be insured in the tunnel for the annealing and cooling of the ware.

Thus, I have illustrated apparatus which may be used in a plurality of different ways and also suggested certain desirable methods according to which this apparatus could be used. Obviously, certain changes may be made in both apparatus and method without departing from the spirit or scope of the present invention. I do not wish to be limited therefore except by the scope of the appended claims, which are to be construed as broadly as the state of the prior art permits.

I claim:

l. Apparatus for annealing glassware, comprising an elongate tunnel, means for moving articles of glassware therethrough, a longitudinally extending flue in heat transferring relation with a predetermined zone of said tunnel adjacent to the ware-entering end thereof, means for supplying a heating medium to said flue at a point spaced a material distance from the Wareentering end of said tunnel, means for supplying a cooling medium to said ue adjacentto the ware-entering end of said tunnel, means for withdrawing media from said flue intermediate the points of supply of the heating and cooling media` respectively. and means for selectively passing desired volumes of said heating or cooling media through at least one zone of said flue intermediate the ware-entering end of said tunnel and the point at which the heating medium may be supplied to said ue to compensate for differences between the temperature at which the ware arrives at the lehr and a predetermined desired temperature as to direction and amount, so as to present the ware on its arrival at a predetermined intermediate point in the lehr at said predetermined desired temperature irrespective of its temperature on being initially placed in the lehr.

2. The method of annealing glassware which comprises, passing the ware through an elongate tunnel lehr, preconditioning the ware to bring it to a predetermined desired temperature by passing adjacent thereto but out of Contact therewith a temperature controlling media selected in accordance with the temperature difference between the temperature of the ware as it arrives in the lehr and the desired temperature thereforpassing other temperature controlling media adjacent to the path of the ware but out of contact therewith for a substanial part of the length of the path of travel of the ware through the lehr, and regulating the temperature of the last named media in the rst portion of its travel adjacent to the path of the ware as it enters the lehr to a point slightly different from the ware temperature in a corrective direction, whereby the last named media are usable adjacent to subsequent portions of the lehr for controlling the temperature gradient of the ware during the annealing and cooling thereof.

HAROLD L. EASTMAN.

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