US3293705A - Apparatus for automatically pouring molten metal - Google Patents

Description

Dec. 27, 1966 R. LENZ ETAL 3,293,705

APPARATUS FOR AUTOMATICALLY POURING MOLTEN METAL Filed Nov. 14, 1963 2 Sheets-Sheet 1 INVENTORS Rudolf Lenz SfQgfHQd Meyer zuHober e J W JW 2g 4 ATTORNEY S Dec. 27, 1966 R. LENZ ETAL APPARATUS FOR AUTOMATICALLY POURING MOLTEN METAL 2 Sheets-Sheet 2 Filed Nov. 14 1963 INVENTORS Rudolf Len Z SiegFr/ecl Meyer zu Hoberge J%& 1

ATTORNEYS United States Patent C) 1 Claim. (a. 22-79 In connection with the general tendency to automate recurring working operations, efforts have also been made to enable the pouring of metals into moulds to be undertaken as far as possible without any manual operations. Thus it is already known to automate to a considerable extent pressure and die-casting processes.

The object of the invention is to provide an automatic control for the operations required in connection with the continuous pouring of liquid metal from an open tiltable crucible into moulds. The possibility of initiating switching operations by means of photo-electric cells, which are influenced by light or infra-red rays, is utilized. The use of infra-red rays diminishes the danger of an undesired switching operation being initiated, for instance by light rays.

The method of automatically pouring fusible metals from a tiltable crucible into a transportable ladle or mould consists in that when a ladle or mould arrives below the spout of a crucible the tilting mechanism is switched on and the crucible tilted to such an extent until a feeler element, which is influenced by the flow of metal which thus occurs, initiates a further tilting of the crucible but at a reduced speed. The liquid metal then flows out of the pouring spout at a moderate speed. A further feeler element, which responds to a predetermined amount of liquid metal in the mould or ladle, give the order for the crucible to tilt backwards until the flow of metal stops. This instant is registered by the first feeler element which gives the order for the tilting movement to cease.

An example of the invention is illustrated in the accompanying drawings in which:

FIG. 1 is a side elevation, partly in section, showing the position of the parts of the apparatus before the pouring of the metal commences;

FIG. 2 is a view similar to that in FIG. 1 showing the position of the parts of the apparatus at the start of the pouring of the metal;

FIG. 3 is a view similar to that in FIG. 1 showing the positions of the parts of the apparatus when the mold has been filled;

FIG. 4 is a view similar to FIG. 1 showing the positions of the parts of the apparatus when the pouring has been interrupted; and

FIG. 5 is a top plan view of a portion of the apparatus showing the relative positions of the mold, the pouring spout and the photo-electric cell.

Referring to the drawings, a crucible 1 filled with fused metal 2 is supported so that it can be tilted about an axis 3 by means of a hydraulic driving device 4. Mounted on the crucible is a feeler element 5 in the form of a photoelectric cell which is sensitive to infra-red rays, this cell being directed towards the flow of metal. A corresponding photo-electric cell 7 is directed towards the inside of the rim of a mould 8 when the latter is in the pouring position. A switch 9 is actuated by the mould 8 when it approaches the furnace, thereby initiating the pouring process.

FIG. 1, as stated above, shows the situation before pouring commences. The mould 8 has not yet reached the switch 9 and the pouring process has not yet commenced.

In FIG. 2 the transportable mould 8 has reached the switch 9 and thus started the pouring operation. By means of a control device 12 the hydraulic tilting mechanism 4 has been switched on and crucible 1 tilted until fused met-a1 at 6 flows from the crucible into the mould. The infra-red radiation from the fused metal acts on the photo-electric cell 5. This latter sends a control impulse to the control device of the hydraulic tilting mechanism, whereupon the control device switches off the tilting mechanism, possibly with a slight delay, or the tilting process is slowed down so that the metal flows out of the crucible at a desired speed and fills the mould 8.

When the level of the metal at 10 (see FIG. 3) in the mould reaches a predetermined height, then it covers the point in the mould to which infra-red sensitive cell 7 is directed and an infra-red beam falls on the photo-electric cell. The photo-electric cell responds and sends a control impulse to the control device 12 of the hydraulic tilting mechanism. This impulse causes the crucible to tilt backwards until the flow of metal stops, as shown in FIG. 4. This stoppage of the flow is noted by the photoelectric cell 5. It stops by means of switching devices known per se the backward tilting movement. Thereupon the mechanism for moving the mould is automatically switched on. After the mould has been removed it is replaced by an empty one. It is tobe mentioned that in addition to the photo-electric cell 7, a further cell arranged in series can be provided to increase the operational safety.

The aforementioned cycle of operations can repeat itself until the crucible is empty. In FIG. 3 a limit switch 11 is shown which is actuated by the crucible when it is entirely or almost empty. It is thus ensured that the crucible cannot be tilted further or is returned to its normal position. In order to perfect the automation, a second device can be provided so as not to have to interrupt the pouring process. The photo-electric cell 7 can be directed in an adjustable manner so that it can be adapted to suit various sizes of moulds or filling quantities. When the casting moulds are provided with rising pipes, the photo-electric cell can be directed towards these. A weighing device for the mould can also be used instead of the photo-electric cell 7. The filling operation is then controlled by the change in weight of the mould.

The invention is not restricted to the constructional form shown in the drawings. The hydraulic drive can be replaced by a pneumatic or electric drive.

Moreover, it is expedient to tilt the crucible at two different speeds. The tilting of the crucible from the position of rest to the pouring position can occur at high speed, whilst adjustment of the inclination of the crucible during the pouring process occurs at a low speed.

The transportation of the mould 8 can be achieved by means of a band conveyor or a turntable.

We claim:

Apparatus for automatically pouring fused metal from a tiltable crucible into a transportable ladle or mold comprising -a tiltable crucible, a transportable ladle or mold, tilting mechanism for said crucible, means for automati cally switching on said tilting mechanism when said ladle or mold attains a predetermined position underneath the pouring spout of said crucibles to cause a first forward tilting movement of said crucible and effect a flow of metal from said crucible into said ladle or mould, a first feeler element comprising a photo-electric cell which is directed toward the path to be taken by the flow of metal Patented Dec. 27,-, 1966;

from said crucible to said mold and which is responsive to said metal flow to initiate a second forward tilting movement of said crucible ata speed which is lower than the speed of said first tilting movement, and a second feeler element which is responsive to a predetermined amount of molten metal in said ladle or mold to cause a backward tilting movement of said crucible, said first feeler element causing the backward tilting movement of said crucible to stop when the flow of metal from said crucible ceases.

References Cited by the Examiner UNITED STATES PATENTS I. SPENCER OVERHOLSER, Primary Examiner.

R. D. BALDWIN, Assistant Examiner.

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