US3882727A

US3882727A - Cooling curve apparatus

Info

Publication number: US3882727A
Application number: US485665A
Authority: US
Inventors: Alexander H Clark; Richard J Hance
Original assignee: Leeds and Northrup Co
Current assignee: Leeds and Northrup Co
Priority date: 1974-07-03
Filing date: 1974-07-03
Publication date: 1975-05-13
Anticipated expiration: 1992-05-13

Abstract

A stand for a cup having a thermocouple located therein for obtaining cooling curves of molten material such as cast iron. The stand is of the type having an electromechanical connection for engagement with mating connecting structure of the cup. The stand includes a pair of upstanding bimetallic blades which snugly engage the wall of the cup when it is placed on the stand which blades distort when molten material is poured into the cup thus heating it and the blades so that the cup may be easily removed from the stand. The bimetallic blades may be part of an assembly readily attached and detached from the stand.

Description

United States Patent n91 Clark et al.

[4 1 May 13,1975

[ COOLING CURVE APPARATUS [75] Inventors: Alexander H. Clark, Norristown,

Pa.; Richard J. Hance, Philadelphia,

[73] Assignee: Leeds & Northrup Company, North Wales, Pa.

[22] Filed: July 3, 1974 211 App]. No.: 485,665

3,813,944 6/1974 Ryntz 3,844,172 10/1974 Jeric 73/359 Primary Examinerl*lerbert Goldstein Attorney, Agent, or Firm-Philemon J. Moore; Raymond F. MacKay [57] ABSTRACT A stand for a cup having a thermocouple located therein for obtaining cooling curves of molten material such as cast iron. The stand is of the type having an electromechanical connection for engagement with mating connecting structure of the cup. The stand includes a pair of upstanding bimetallic blades which snugly engage the wall of the cup when it is placed on the stand which blades distort when molten material is poured into the cup thus heating it and the blades so that the cup may be easily removed from the stand. The bimetallic blades may be part of an assembly readily attached and detached from the stand.

9 Claims, 2 Drawing Figures Pmmm 3,882,727

FIG. 2

FIG. I

COOLING CURVE APPARATUS BACKGROUND OF THE INVENTION 1. Field of the Invention Apparatus for obtaining cooling curves of molten materials may be found in Official U.S. Patent Office subclasses relating to Measuring and Testing, Thermometer, Current Generating type.

2. Description of Prior Art Apparatus employing expendable cups or molds containing a heat sensing device for obtaining a cooling curve of a molten material have been referred to as expendable phase change detector devices as described and claimed in U.S. Pat. No. 3,267,732 which became Re.26,409. Molds of the foregoing type include a thermocouple and plug-in means to make an electromechanical connection thereto. Such molds are normally placed on a suitable stand having mating electromechanical connector structure. A recorder connected to the stand will record the temperature of material poured into the mold as it cools. The material of the mold and the speed of response of the recorder are related in a manner such that arrest points in the cooling curve are exhibited for determination of the composition of the material placed in the mold. It is desirable that such molds be securely supported on the stand so that good electrical connection is maintained while the molten sample is poured into the mold and during cooling of the sample. It is also desirable to be able quickly and easily to remove the hot mold from the stand in a manner which is safe and convenient for an operator.

Applicants have discovered an arrangement whereby a mold at ambient temperature is held securely on a stand by means which automatically releases its hold on the mold as the mold becomes heated by molten material poured therein so that the mold may be easily removed from the stand.

SUMMARY OF THE INVENTION In accordance with applicants invention a holder is provided for an expendable mold containing a heat sensing element for phase change detection apparatus of the type having electromechanical contact structure for plug-in engagement with mating electromechanical contact structure of a test stand. The holder comprises temperature responsive means to engage and provide a holding force on an expendable mold when the mold and temperature responsive means are substantially at the ambient temperature of a test location and release the holding force when the temperature responsive means is heated to a temperature substantially higher than the ambient temperature by molten material poured into the mold. The holder also includes means for securing the temperature responsive means to the test stand in a position to engage and release the mold. More specifically the temperature responsive means which provides the holding force is comprised of bimetallic means. The bimetallic means may take the form of a bimetallic blade supported in position to engage the mold at ambient temperature. The blade when heated deforms in a directionto move away from engagement with the mold to render the mold easily removable. In a preferred form of the invention the holder may include a pair of blades of bimetallic material supported diametrically opposite each other.

It is an object of applicants invention to provide a test stand for an expendable phase change detector device, such as a mold containing temperature sensing means. The stand comprises a base and upright structure for supporting a mold containing temperature sensing means, the structure also supporting electrical contacts for connection with electrical conductors of the temperature sensing means of the mold. The stand additionally includes heat responsive means which when the stand and the mold are at substantially the ambient temperature of a test location will engage the mold placed on the stand for retention of the mold on the stand. The heat responsive means is operable upon the application of heat thereto to become disengaged from the mold for ease of removal of the mold from the stand. More specifically the heat responsive means includes a bimetallic strip mechanically engageable with the mold. Preferably heat is applied to the heat responsive means through a wall of the mold engaged with the heat responsive means when the mold is filled with a molten material the temperature of which is above the ambient temperature of the test location.

It is further an object of our invention to provide a test stand for an expendable cup of a cooling curve apparatus wherein the stand is of the type including electrical contact structure for connection with electrical contact structure of a cup. The stand additionally includes a plurality of upstanding blades at least one of which is comprised of a bimetallic strip material. The blades are secured to the stand in a position to engage a wall of a cup when the cup is installed on the stand with the cup and stand substantially at the temperature of a test location. Heating of the cup and the blades as a result of pouring hot molten material into the cup, after an adequate rise in temperature, causing said bimetallic strip to deform in a direction to become disengaged from the wall of the cup. More specifically the blades are supported by a ring structure to form a holder which is readily attachable and detachable from the stand.

For additional objects and for a better understanding of applicants invention and the advantages obtained by its use the following description and claims should be read with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation partly in section illustrative of an expendable cup and stand therefor with a holder in accordance with applicants invention, and

FIG. 2 is a side elevation on an enlarged scale showing a cup on the upper portion of the stand of FIG. 1 as viewed from the right side of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT In FIG. 1 there is shown an expendable cup 15 which is also known as an expendable phase change detector device. The cup is adapted to be placed on a stand 10 of a type which has become quite familiar to those skilled in the art. The stand 10 comprises a conduit box 11 mounted by means of a short nipple and reducer to a pipe flange so that the structure may be supported on the floor or on a table. The conduit box, short nipple, reducer and pipe flange are all commercially available items well known to those skilled in the art. Projecting from the upper end of the stand 11 is a short nipple 12 which contains therein a receptacle having a pair of female contact structures to receive in plug-in relation thereto the

connector pins

13a and 13b of a connector 13 which is an electromechanical connector for supporting an expendable phase change detector in the form of the mold or cup 15.

Pins

13a, 13b which plug into the female connectors contained within the nipple 12 are connected through the stand to a cable 18 for making electrical connection with a recording device, not shown, in a manner well understood by those skilled in the arts. A more complete description of cooling curve apparatus is set forth in US. Pat. Re. 26,409 and references contained therein.

The connector 13 includes a pair of electrically

conductive connector pins

13c, 13d electrically connected to

pins

13a, 13b. It also includes a pair of electrically nonconductive cup orienting posts I3e, 13f; the post 13f being located directly behind post Be is obscured thereby in FIG. 1.

A complete description of the apparatus so far described is published in Leeds 81. Northrup Co. brochure entitled Before pouring check with Tectip which is available from that company located at North Wales, Pennsylvania 19454 by requesting plubication E2.2241FL published May 1972. The expendable cup 15 has therein a thermocouple 16 with a heat sensing portion 17 comprised of a junction between a pair of

wires

17a, 17b. The wires l7a, 17b are bent outwardly at the bottom of the cup into

recesses

15a, 15b to form plug-in electrical contacts to mate with

pins

13c, 13d. Upon placing cup 15 on the stand with the

wires

17a, 17b in electromechanical connection with the

pins

13c, 13d the junction 17 of the thermocouple 16 is connected electrically through the stand by way of the cable 18 to a recorder, not shown, in a manner well understood by those skilled in the art and as described in the above mentioned Leeds & Northrup Co. publication. As best shown in FIG. 2,

posts

13e and 13f of connector l3 cooperate with

fins

15c and 15d of the cup 15 to insure making the electrical connection with the proper polarity. The foregoing apparatus has been commercially available from the Leeds & Northrup Company for several years and has proved quite satisfactory for its intended purpose. It per se is not applicants present invention.

Some users of the above described apparatus, which is characterized by ease of removal of the expendable cup by merely tipping it from the stand so that a new cup may be quickly plugged-in, find use for the apparatus under conditions where it is deemed necessary to hold the cup on the stand more securely during the pouring of a sample and obtaining a cooling curve.

In order to provide the test stand with means for more securely holding the cup on the stand for a limited period of time applicants have devised a structure comprised of a metal ring 20 which may be secured to the nipple 12 as by

screws

21, 22. Welded or otherwise secured to ring 20 is a pair of

upstanding blades

23, 24 of bimetallic material such as is best shown in FIG. 2. The dimensions and locations of various parts are such that with the stand and cup at the ambient temperature of the test location, a cup 15 when plugged onto the stand 11 will be received in gripping engagement between the

blades

23, 24 in the manner shown in FIG. 2. After molten material such as cast iron or steel is poured into the cup 15 it will heat the cup to a high temperature. For example molten iron poured into the mold will be at a temperature above about 2,400 Fahrenheit. Heat will be conducted through the walls of the cup thus heating the

blades

23, 24 which causes the blades to deflect in a manner such that they assume positions as indicated by the dash-line position for each of the blades due to the fact that the blades are made of a bimetallic material. As is well understood by those skilled in the arts, deflection of the blades is caused by the differing rates of expansion of the different materi als which are bonded together to form bimetallic strip material from which the blades are fabricated. The extent of the deflection has been exaggerated in FIG. 2 more clearly to illustrate the manner in which the blades move away from contact with the sides of the cup so that it may be readily removed from the stand in the manner previously described. The fit of the

pins

13c, 13d with respect to the

electrical contacts

17a, 17b and the loose fit between the

guide posts

13e, 13f with respect to the ribs c and I511 of the cup are such that it is easy to remove the detector device by merely knocking it from the stand by a quick kick or by the use of a rod or stick.

In a modification of applicants invention as reduced to practice bimetallic strip about one-fourth inch wide comprised of one-sixteenth inch thick Monel metal brazed to a one-sixteenth thick copper-manganese alloy was found to be satisfactory. It took about four minutes for the material to deflect sufficiently to become disengaged from the cup when being heated by molten metal and about the same amount of time for the blades to cool and return to normal after a hot cup was removed. As is readily apparent, the ring with the

blades

23, 24 may be readily mounted on or removed from a stand 10 strictly in accordance with an operators preference. If desired a stand may also be constructed with heat responsive means as a permanent part thereof and using arrangements of components different from the parts and arrangements shown in applicants drawings.

While applicants have described their device in detail it is believed apparent that the principals employed by applicants may be applied in the formation of devices for like purpose which may be constructed in a different though equivalent form. The structure described is in no way intended to be limiting.

What is claimed is:

l. A holder for an expendable mold for phase change detection apparatus of the type wherein a mold containing a heat sensing element has electromechanical contact structure for plug-in engagement with mating electromechanical contact structure of a test stand,

said holder comprising:

temperature responsive means to engage and provide a holding force on an expendable mold when said mold and said temperature responsive means are at substantially the ambient temperature of a test location and release said holding force when said temperature responsive means is heated to a temperature substantially higher than said ambient temperature by molten material poured into said mold, and

means for securing said temperature responsive means to said test stand in a position to engage and release said mold.

2. A holder according to claim 1 wherein said temperature responsive means is comprised of bimetallic means.

3. A holder according to claim 2 wherein said bimetallic means is'in the form of a bimetallic strip supported in position to engage said mold at ambient temperature and which when heated deforms in a direction to move away from engagement with said mold.

4. A holder according to claim 2 wherein said bimetallic means is comprised of a pair of bimetallic blades supported diametrically opposite each other.

5. A test stand 'for an expendable phase change detector device,- said stand comprising:

a base and upright structure for supporting a mold containing temperature sensing means, said structure also supporting electrical contacts for connection with electrical conductors of said temperature sensing means of said mold, and

heat responsive means which when the stand and a mold are at substantially the ambient temperature of a test location will engage a mold placed on said stand for retention of the mold on the stand and which means is operable upon the application of heat thereto to become disengaged from the mold for ease of removal of said mold from said stand.

6. A test stand according to claim 5 wherein said heat responsive means includes a bimetallic strip mechanically engageable with said mold.

7. A test stand according to claim 5 wherein heat is applied to said heat responsive means through a wall of a mold engaged with said heat responsive means when said mold is filled with a molten material the temperature of which is above the ambient temperature of the test location.

8. A test stand for an expendable cup of a cooling curve apparatus, said stand being of the type including electrical contact structure for connection with electrical contact structure of an expendable phase change detector cup, said stand additionally including:

a plurality of upstanding blades at least one of which 9. A test stand according to claim 8 wherein said blades are supported by ring structure to form a holder which is readily attachable and detachable from said stand.

Claims

1. A holder for an expendable mold for phase change detection apparatus of the type wherein a mold containing a heat sensing element has electromechanical contact structure for plug-in engagement with mating electromechanical contact structure of a test stand, said holder comprising: temperature responsive means to engage and provide a holding force on an expendable mold when said mold and said temperature responsive means are at substantially the ambient temperature of a test location and release said holding force when said temperature responsive means is heated to a temperature substantially higher than said ambient temperature by molten material poured into said mold, and means for securing said temperature responsive means to said test stand in a position to engage and release said mold.

3. A holder according to claim 2 wherein said bimetallic means is in the form of a bimetallic strip supported in position to engage said mold at ambient temperature and which when heated deforms in a direction to move away from engagement with said mold.

5. A test stand for an expendable phase change detector device, said stand comprising: a base and upright structure for supporting a mold containing temperature sensing means, said structure also supporting electrical contacts for connection with electrical conductors of said temperature sensing means of said mold, and heat responsive means which when the stand and a mold are at substantially the ambient temperature of a test location will engage a mold placed on said stand for retention of the mold on the stand and which means is operable upon the application of heat thereto to become disengaged from the mold for ease of removal of said mold from said stand.

8. A test stand for an expendable cup of a cooling curve apparatus, said stand being of the type including electrical contact structure for connection with electrical contact structure of an expendable phase change detector cup, said stand additionally including: a plurality of upstanding blades at least one of which is comprised of bimetallic strip material, said blades being secured to said stand in a position to engage a wall of a cup when a cup is installed on said stand with said cup and stand substantially at the temperature of a test location, and heating of the cup and said blades as the result of pouring hot molten material into said cup after an adequate rise in temperature causing said bimetallic strip to deform in a direction to become disengaged from said wall of said cup.

9. A test stand according to claim 8 wherein said blades are supported by ring structure to form a holder which is readily attachable and detachable from said stand.