US2872494A - Device for tightening and loosening current supply plates on electrodes in electric furnaces - Google Patents
Device for tightening and loosening current supply plates on electrodes in electric furnaces Download PDFInfo
- Publication number
- US2872494A US2872494A US538712A US53871255A US2872494A US 2872494 A US2872494 A US 2872494A US 538712 A US538712 A US 538712A US 53871255 A US53871255 A US 53871255A US 2872494 A US2872494 A US 2872494A
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- Prior art keywords
- current supply
- supply plates
- pressure ring
- electrode
- draw
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B7/00—Heating by electric discharge
- H05B7/02—Details
- H05B7/10—Mountings, supports, terminals or arrangements for feeding or guiding electrodes
- H05B7/103—Mountings, supports or terminals with jaws
- H05B7/105—Mountings, supports or terminals with jaws comprising more than two jaws equally spaced along circumference, e.g. ring holders
Definitions
- the pressure ring described below may comprise a number of elements or segments which may be connected with one another so as to be resistant to bending.
- Such hydraulic apparatus may serve to operate a group of draw rods or may serve to operate all the draw rods simultaneously.
- the jacket may also be fitted with a water-cooling system.
- the device according to this invention may also be constructed in a manner such that the pressure ring joins the movement of the draw rods with all current supply plates being necessarily and simultaneously tightened o loosened.
- the pressure ring is connected with the movable elements to receive only or almost only tensile power. 7 v v
- the pressure ring, the levers and bolts and, if desired, the draw rods are advantageously made of an antimagnetic material, for example a copper alloy or stainless steel.
- the current supply plates are connected with the movable elements in a manner such that the resulting action tightens the plates in their entire length as evenly as possible.
- the position of the current supply plates is recorded by a special recording device.
- Fig. 1 is a side view, partly in section and partly in elevation, of a mechanism embodying the present invention.
- Fig. 2 is a side view, partly in section and partly in 2,872,494 Patentedli'eb. 3, 1959 elevation, of a second embodiment of the present invention.
- Fig. 3 is an enlarged, detailed view, partly in section and partly in elevation, of the linkage assembly connecting a draw rod of the embodiment of Fig. 1 to the corresponding current supply plate.
- Fig. 4 is an enlarged, detailed view, similar to Fig. 3, of the corresponding linkage assembly in the embodiment of Fig. 2.
- Fig. 5 is a fragmentary top plan view of the device of Fig. 1 with parts broken away.
- Fig. 6 is a sectional view of the draw rod pressure means at the upper end of the housing in the embodiment of Fig. 1.
- Figure 1 shows a device with a determined reciprocal position in vertical sense of the current supply plates and the pressure ring, every individual current supply plate being tightened or loosened by a pertinent draw rod; the pressure ring serves as support for all the crank gears.
- the device according to this invention for tight ening current supply plates 1 is surrounded by a jacket 3, the lower part4 of which is cooled with water.
- the device itself comprises a multisectional pressure ring 5 rigidly connected with jacket 3 by a suspension arrangement.
- pressure ring 5 is connected in a flexible manner with levers 8 and '9 which have a flexible connection at 10 and 11 to draw rod 12 and levers 13 and 14.
- Draw rod 12 is suspended atspring 15 which, like suspension pivots 16 of current supply plates 1, is connected with the upper part 17 of jacket 3.
- Tension lock 18 serves to regulate the tension of spring 15.
- the spring can be compressed by means of compressed air or water under pressure which is introduced through conduit 19.
- Each of current supply plates 1 together with pressure ring 5, levers 8, 9, 13 and 14 forms a cinematic crank gear, the support of which is represented by the pressure ring 5.
- draw rod 12 with drawing spring 15 joints 10 and 11 are drawn upward.
- Spring 15 can be compressed by means of compressed air or water under pressure.
- draw rod 12 moves downward, the angles between the levers are reduced and the current supply plates 1 are thereby released from electrode 2.
- Figure 2 illustrates another construction of the device wherein the pressure ring participates in the movement of the draw rods with all current supply plates being consequently and simultaneously tightened or loosened.
- 1 represents the current supply plates, 2 the electrode, 3 the jacket with water cooling system, 4 and 5 the pressure ring which participates in the movements of draw rod 12.
- Tension lock 18 is connected with draw rod 12.
- Levers 20 and 21 connect pressure ring 5 with current supply plates 1 by means of bearing blocks 6 and 7 fixed at pressure ring 5.
- Draw rod 12 is suspended at spring 15 which, like suspension pivots 16 of current supply plates 1, is connected with the upper part 17 of jacket 3. Through conduit 19 compressed air or water under pressure can be introduced to compress spring 15.
- FIG. 6 12 represents a draw rod, 16 a suspension pivot of a current supply plate, 17 the upper part of the jacket, and is the spring compressible by compressed air or water under pressure introduced through conduit 19.
- Figure 3 1 represents a current supply plate, 2 the electrode, 4 the water-cooling system of the jacket, 5 the pressure ring, 6 and 7 the bearing blocks, and 8 and 9 the levers which at it and 11 have a flexible connection to draw rod 12 and levers 13 and 14.
- Figure 3 corresponds to Figure 1.
- Figure 4 shows -a part of Figure 2 on a larger scale.
- the numerals designate the following parts:
- 1 represents a current supply plate
- 2 the electrode
- 4 the water-cooling system of the jacket
- 5 the pressure ring
- 12 the draw rod.
- Levers and 21 connect pressure ring 5 with current supply plate 1 by means of bearing blocks 6 and 7 fixed at 5.
- Apparatus for holding and releasing an electrode in an electric furnace comprising a housing encompassing a vertically extending electrode, a plurality of current supply plates circumferentially surrounding the electrode and being individually supported by movable holding means connected to said housing, said holding means permitting movement of said current supply plates toward and away from the electrode, a ring circumferentially encompassing said current supply plates, and individual linkage means pivotally connecting each of said current supply plates to said ring, each of said linkage means including a pair of vertically spaced links wherein each link of the pair is pivotally connected, at one end, to its respective current supply plate and is pivotally connected, at its other end, to an element which is itself rigidly connected to the lower portion of avertically reciprocable draw rod, there being a draw rod for each pair of vertically spaced links, the upper end of each of the draw rods being operatively connected with means for effecting longitudinal movement of said draw rods, movement of said draw rods in one vertical direction simultaneously forcing the corresponding current supply plates into contact with the electrode while movement of the
- each link of said pair also being connected to its said other end to a second link, each of said second links being, in turn, pivotally connected to said ring, and said ring being rigidly connected to said housing.
- said element comprises a bearing block rigidly connected to said ring, said ring being, in turn, rigidly connected with said lower portion of the vertically reciprocable draw rod.
- V 6 The improvement as set forth in claim 1 wherein a cooling jacket circumferentially surrounds the current supply plates.
- apparatus for holding and moving forward a continuous electrode in an electro-therrnal furnace said apparatus including a plurality of current supply plates circumferentially surrounding the continuous electrode adjacent the lower end thereof, the improvement comprising means individually supporting the weight of the current supply plates and permitting movement of the current supply plates into and out of contact with the electrode, a pressure ring circumferentially encompassing the current supply plates, separate linkage means pivotally connected to each of said current supply plates, a second linkage means pivotally connected to the free end of each of said separate linkage means, means rigidly associated withsaid pressure ring and pivotally connected to each of the free ends of said second linkage means, a draw rod operatively associated with the pivotal connection between each of said separate and second linkages, and means operatively associated with each of said draw rods for longitudinal movement thereof, movement of each of the draw rods in one direction simultaneously forcing the current supply plates into contact with the electrode and movement in the other direction withdrawing the current supply plates from contact with the electrode.
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- Engineering & Computer Science (AREA)
- Plasma & Fusion (AREA)
- Heat Treatment Of Articles (AREA)
Description
: Feb. 3, 1959 RUMBERG ETAL 2,872,494
' DEVICE FOR TIGHTENING AND LOOSENING CURRENT SUPPLY PLATES 0N ELECTRODES IN ELECTRIC FURNACES Filed 001. 5, 1955 3 Sheed's-Shet 1 FIGZ.
INVENTORS ALFRED RUMBERG wILHELMlziMGEN MARIILIN IHEls ATTORNEY5 1959 A. RUMBERG ETAL OR 11cm; PLATES ON EL.
2,872,494 CURRENT SUPPLY C'FURNACES NING AND LOOSENING E TRODES IN ELECTRI DEVICE F Filed Oct. 5, 1955 5 Sheets-Sheet 2 INVENTORS ALFRED RUMBERG WILHELM DAMGEN MARTIN THEIS BY /6 5 ATTORNEYS ETAL A. RUMBER 2, 7 II'I'EIIIIIG AND L ENING CURRENT SUPPLY ELECTRODES IN ELECTRIC FURNA Feb. 3, 1959 DEVICE 1 03 TIC PLATES ON 1955 CES 3 Sheets-Sheet 5 Filed Oct. 5,
rim.
INVENTORS United States PatentO DEVICE FOR TIGHTENING AND LOOSENING CURRENT SUPPLY PLATES N ELECTRODES IN ELECTRIC FURNACES Alfred Rumberg and Wilhelm Diimgen, Hurth, near Koln, and Martin Theis, Fisclienich, near Koln, Germany, assignors to Knapsack-Griesheim Aktiengesellschaft, Knapsack, near Koln, Germany, a corporation of Germany Application October 5, 1955, Serial No. 538,712 Claims priority, application Germany October 13, 1954 8 Claims. (Cl. 13--16) This invention relates to a device for tightening and loosening current supply plates on electrodes in electric furnaces.
We have found a particularly advantageous device which comprises current supply plates connected by movable elements with a pressure ring and a number of draw rods to form cinematic crank gears. In this device the current supply plates are tightened by moving the draw rods in one direction parallel to the electrode axis, and they are loosened by moving the draw rods in the reverse direction parallel to the eletcrode axis.
The pressure ring described below may comprise a number of elements or segments which may be connected with one another so as to be resistant to bending.
It is an object of this invention to provide the device with springs for tightening the current supply plates, which springs act on the draw rods moving the pressure ring upand downward.
According to this invention, it is also possible to atrange a hydraulic device which allows of loosening and releasing the current supply plates.
Such hydraulic apparatus may serve to operate a group of draw rods or may serve to operate all the draw rods simultaneously.
It is possible to surround the entire device wtih a jacket which, when a closed furnace is concerned, projects through the furnace lid into said furnace. The jacket may also be fitted with a water-cooling system.
It is another object of this invention to tighten and to loosen every individual current supply plate by a pertinent draw rod without co-operation of the pressure ring which serves as support for all the crank gears.
The device according to this invention may also be constructed in a manner such that the pressure ring joins the movement of the draw rods with all current supply plates being necessarily and simultaneously tightened o loosened.
In the device of this invention the pressure ring is connected with the movable elements to receive only or almost only tensile power. 7 v v In order to avoid inductive heating, the pressure ring, the levers and bolts and, if desired, the draw rods are advantageously made of an antimagnetic material, for example a copper alloy or stainless steel.
According to this invention the current supply plates are connected with the movable elements in a manner such that the resulting action tightens the plates in their entire length as evenly as possible.
The position of the current supply plates is recorded by a special recording device.
Fig. 1 is a side view, partly in section and partly in elevation, of a mechanism embodying the present invention.
Fig. 2 is a side view, partly in section and partly in 2,872,494 Patentedli'eb. 3, 1959 elevation, of a second embodiment of the present invention.
Fig. 3 is an enlarged, detailed view, partly in section and partly in elevation, of the linkage assembly connecting a draw rod of the embodiment of Fig. 1 to the corresponding current supply plate.
Fig. 4 is an enlarged, detailed view, similar to Fig. 3, of the corresponding linkage assembly in the embodiment of Fig. 2.
Fig. 5 is a fragmentary top plan view of the device of Fig. 1 with parts broken away.
Fig. 6 is a sectional view of the draw rod pressure means at the upper end of the housing in the embodiment of Fig. 1.
Figures 1 and 2 of the accompanying drawing shown diagrammatically serve to illustrate the invention:
Figure 1 shows a device with a determined reciprocal position in vertical sense of the current supply plates and the pressure ring, every individual current supply plate being tightened or loosened by a pertinent draw rod; the pressure ring serves as support for all the crank gears.
In Figure 1 the numerals designate the following parts:
Each of current supply plates 1 together with pressure ring 5, levers 8, 9, 13 and 14 forms a cinematic crank gear, the support of which is represented by the pressure ring 5. By draw rod 12 with drawing spring 15 joints 10 and 11 are drawn upward. Thereby theangle formed by levers 8 and 9 and levers 13 and 14 is enlarged and current supply plates 1 are tightened to electrode 2; Spring 15 can be compressed by means of compressed air or water under pressure. Thereby draw rod 12 moves downward, the angles between the levers are reduced and the current supply plates 1 are thereby released from electrode 2.
, Figure 2 illustrates another construction of the device wherein the pressure ring participates in the movement of the draw rods with all current supply plates being consequently and simultaneously tightened or loosened.
In Figure 2 the numerals designate the following parts:
1 represents the current supply plates, 2 the electrode, 3 the jacket with water cooling system, 4 and 5 the pressure ring which participates in the movements of draw rod 12. Tension lock 18 is connected with draw rod 12. Levers 20 and 21 connect pressure ring 5 with current supply plates 1 by means of bearing blocks 6 and 7 fixed at pressure ring 5. Draw rod 12 is suspended at spring 15 which, like suspension pivots 16 of current supply plates 1, is connected with the upper part 17 of jacket 3. Through conduit 19 compressed air or water under pressure can be introduced to compress spring 15.
The force of spring 15 which is regulated by tension lock 18 lifts pressure ring 5 by means of draw rod 12. The pressure ring 5 together with each of current supply plates 1 and the pertinent levers 20 and 21 forms a cinematic crank gear. If pressure ring 5 is lifted, levers 3 20 and 21 tighten all current supply plates 1 to electrode 2. If pressure ring is lowered, current supply plates 1 are loosened from electrode 2.
Figures 3 to 6 of the accompanying drawings show individual parts of the device on a larger scale.
In Figure 5 the numerals designate the following parts: 1 represents the current supply plates, 2 the electrode, 4 the water-cooling system of the jacket, and 5 the pressure ring which joins in the movement of draw-rods 12.
In Figure 6, 12 represents a draw rod, 16 a suspension pivot of a current supply plate, 17 the upper part of the jacket, and is the spring compressible by compressed air or water under pressure introduced through conduit 19.
In Figure 3, 1 represents a current supply plate, 2 the electrode, 4 the water-cooling system of the jacket, 5 the pressure ring, 6 and 7 the bearing blocks, and 8 and 9 the levers which at it and 11 have a flexible connection to draw rod 12 and levers 13 and 14. With regard to the construction of the individual parts, Figure 3 corresponds to Figure 1.
Figure 4 shows -a part of Figure 2 on a larger scale. The numerals designate the following parts:
1 represents a current supply plate, 2 the electrode, 4 the water-cooling system of the jacket, 5 the pressure ring, and 12 the draw rod. Levers and 21 connect pressure ring 5 with current supply plate 1 by means of bearing blocks 6 and 7 fixed at 5.
We claim:
1. Apparatus for holding and releasing an electrode in an electric furnace comprising a housing encompassing a vertically extending electrode, a plurality of current supply plates circumferentially surrounding the electrode and being individually supported by movable holding means connected to said housing, said holding means permitting movement of said current supply plates toward and away from the electrode, a ring circumferentially encompassing said current supply plates, and individual linkage means pivotally connecting each of said current supply plates to said ring, each of said linkage means including a pair of vertically spaced links wherein each link of the pair is pivotally connected, at one end, to its respective current supply plate and is pivotally connected, at its other end, to an element which is itself rigidly connected to the lower portion of avertically reciprocable draw rod, there being a draw rod for each pair of vertically spaced links, the upper end of each of the draw rods being operatively connected with means for effecting longitudinal movement of said draw rods, movement of said draw rods in one vertical direction simultaneously forcing the corresponding current supply plates into contact with the electrode while movement of the draw rods in the opposite vertical direction acts to withdraw the current supply plates away from the electrode.
2. The apparatus of claim 1 wherein said element is a pivot pin on the corresponding draw rod, each link of said pair also being connected to its said other end to a second link, each of said second links being, in turn, pivotally connected to said ring, and said ring being rigidly connected to said housing.
3. The apparatus of claim 1 wherein said element comprises a bearing block rigidly connected to said ring, said ring being, in turn, rigidly connected with said lower portion of the vertically reciprocable draw rod.
4. The improvement as set forth in claim 1 wherein said. means operatively connected with each of said draw rods for effecting a longitudinal movement of said draw rods includes means normally forcing each of said draw rods in the one direction and means for overcoming the force and moving each of draw rods in the other direction.
5. The improvement as set forth in claim 4 wherein the means normally forcing each of the draw rods in one direction includes spring loaded means and the means for overcoming the force of the spring loaded means includes hydraulic means.
V 6. The improvement as set forth in claim 1 wherein a cooling jacket circumferentially surrounds the current supply plates.
7. In apparatus for holding and moving forward a continuous electrode in an electro-therrnal furnace, said apparatus including a plurality of current supply plates circumferentially surrounding the continuous electrode adjacent the lower end thereof, the improvement comprising means individually supporting the weight of the current supply plates and permitting movement of the current supply plates into and out of contact with the electrode, a pressure ring circumferentially encompassing the current supply plates, separate linkage means pivotally connected to each of said current supply plates, a second linkage means pivotally connected to the free end of each of said separate linkage means, means rigidly associated withsaid pressure ring and pivotally connected to each of the free ends of said second linkage means, a draw rod operatively associated with the pivotal connection between each of said separate and second linkages, and means operatively associated with each of said draw rods for longitudinal movement thereof, movement of each of the draw rods in one direction simultaneously forcing the current supply plates into contact with the electrode and movement in the other direction withdrawing the current supply plates from contact with the electrode.
8. The improvement as set forth in claim 7 wherein two parallel separate linkage means are pivotally connected to each of said current supply plates and a second linkage means is pivotally connected to each of the free ends of the separate linkage means and pivotally connected at their other ends in parallel to the means rigidly associated with said pressure ring, each of the pivotal connections of the parallel separate and second linkage means being pivotally connected to a draw rod.
References Cited in the file of this patent UNITED STATES PATENTS Ritter et al. Jan. 4, 1955 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent N0. 2,872,494 February 3, 1959 Alfred Rumberg et al.
It is hereby certified that error appears in the-printed specification of the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.
KARL AXLINE ROBERT C. WATSON Attesting Officer Commissioner of Patents UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 2,872 494 February 3, 1959 Alfred Rumberg et al.
It is hereby certified that error appears in the-printed specification of the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.
(SEAL) Attest:
KARL H. AXLINE Attesting Officer ROBERT C. WATSON Commissioner of Patents
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
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DE2872494X | 1954-10-13 |
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US2872494A true US2872494A (en) | 1959-02-03 |
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US538712A Expired - Lifetime US2872494A (en) | 1954-10-13 | 1955-10-05 | Device for tightening and loosening current supply plates on electrodes in electric furnaces |
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Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2969410A (en) * | 1958-03-22 | 1961-01-24 | Knapsack Ag | Device for tightening and loosening current supply plates on electrodes in electric furnaces |
US3634589A (en) * | 1969-11-13 | 1972-01-11 | Elkem As | Control mechanism for an electrode-clamping assembly in an electric furnace |
CN105008227A (en) * | 2013-02-07 | 2015-10-28 | 伊奎希尔德医疗有限公司 | Improvements to closed drug transfer system |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1677712A (en) * | 1925-12-28 | 1928-07-17 | Firm I G Farbenindustrie Ag | Electrode holder |
US2133305A (en) * | 1936-09-03 | 1938-10-18 | Payne William Harvey | Clamp for electric arc furnace electrodes |
US2297484A (en) * | 1939-10-09 | 1942-09-29 | Lehrer Fritz | Electrode holder |
US2698871A (en) * | 1950-04-03 | 1955-01-04 | Fur Stickstoffdunger Knapsack | Electrode holding device for electrothermic melting furnaces |
-
1955
- 1955-10-05 US US538712A patent/US2872494A/en not_active Expired - Lifetime
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1677712A (en) * | 1925-12-28 | 1928-07-17 | Firm I G Farbenindustrie Ag | Electrode holder |
US2133305A (en) * | 1936-09-03 | 1938-10-18 | Payne William Harvey | Clamp for electric arc furnace electrodes |
US2297484A (en) * | 1939-10-09 | 1942-09-29 | Lehrer Fritz | Electrode holder |
US2698871A (en) * | 1950-04-03 | 1955-01-04 | Fur Stickstoffdunger Knapsack | Electrode holding device for electrothermic melting furnaces |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2969410A (en) * | 1958-03-22 | 1961-01-24 | Knapsack Ag | Device for tightening and loosening current supply plates on electrodes in electric furnaces |
US3634589A (en) * | 1969-11-13 | 1972-01-11 | Elkem As | Control mechanism for an electrode-clamping assembly in an electric furnace |
CN105008227A (en) * | 2013-02-07 | 2015-10-28 | 伊奎希尔德医疗有限公司 | Improvements to closed drug transfer system |
US9510997B2 (en) | 2013-02-07 | 2016-12-06 | Equashield Medical Ltd. | Closed drug transfer system |
CN105008227B (en) * | 2013-02-07 | 2017-03-08 | 伊奎希尔德医疗有限公司 | Improvement to the drug transfer system of closing |
US9610222B2 (en) | 2013-02-07 | 2017-04-04 | Equashield Medical Ltd. | Closed drug transfer system |
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