USRE14421E - Abkahatff mabthimtus ebichsktt - Google Patents

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A. M ERICHSEN. PROCESS AND APPARATUS FOR TESTING METAL SHEETS, 6w.

A PPLHEATION FILED DEG-3Q- 1M6- Reissued Jan. 8, 1918.

I I INVENTOR WITNESS I a I! sults of the test dependinfi UNITED STATES PATENT OFFICE.

mTHTIIUS EBICHSEN, 01

NORWAY.

PROCESS APPARATUS FOR TESTIN G METAL SHEETS, M.

s utum! pf Beiuued Letters Patent. Reiggued 3 19 Ofllinal Io. 1,084,819, dated April 21, 1914, Serial llo. 740,518, filed January 6, 1813. Application for reissue filed December 30, 1918. Serial 1V0. 189,813.

To all whom it may concern:

Be it known that I, Anaemia Manrnmms EmcnsnN, a subject of the king of Norway, and resident of Christiania Norway, have invented certain new an useful Improvements in Processes and Apparams for TestingMetal Sheets, &c., of which the following is a specification.

The present invention relates to a rocess and an apparatus for testing the resistance to compressive and tensile strains of metal sheets and plates.

According to the im roved process the metal sheet undergoes t e strains to which it becomes submitted in the practice when compressed, extended or stamped, the reupon the stress of ultimate tenacity as we sistance of the material.

The rooess consists essentially in that, contrarily to the usual tests performed,'the metal sheet to be tested is engaged between a matrix and a holder, a'constant free space or' lay of slight extent being left around sai sheet in order not to impede with the free manifestation of the natural proprieties of the metal but at the same time avoid formation of folds or plaits, and is freely pressed by the die in such a manner that the extending of the metal is gradually performed until the stress of ultimate tenacity is attained. The phases of the test may readily be watchedand the resulting numbers may be read directly on the appara tus.

One constructive form of the invention is shown in the accompanying drawing, in.

which: A

Figure 1 is a lateral view of the apparatus. artly shown in section. Fig. 2 is the hand wheel for actuating the lunger die. Fig. 3 is a difierent constructive form of the working of the formed. I

The testing proces is performed as follows: The metal sheet or plate is engaged in the apparatus and cut, so as to 0 er a sheet a rthe test is percircular shape, by means of the ring R, the matrix B and the extension of the holder G. Then the holder C is screwed in until the scale of the hand wheel corresponds to the thickness of the sheet, a certain play bein left to the disk between the parts B and is provided with a scale as upon the re- I arts; Fig. 4 shows the shape This play is obtained by cutting. out the compressin surface of the holder C in such a manner t at the distance between its outer shaped surface and the compressing.

rin' sur ace of the ring R is smaller than the distance between the inner ring shaped surface of the holder C and the compressing surface of the matrix B. The cutting of the metal sheet is produced by actuating vthe hand wheel K. The perigheryof wheel K to indicate the resistance of the metal sheet. For instance,

if the pitch of the threaded portion-of the holder C is five millimeters, the graduations on wheel K will be divided into 'five parts, each partcorresponding to one movement of one millimeter. Then. the metal disk undergoes the action of the die A' which is driven against said disk when the threaded shaft L is rotated by means, of the hand wheel G. As the metal disk owing to the play is not firmly maintained between the compressing surfaces of B and C, it is extended by means of the die A. The cone shaped hollow becomes gradually enlar d while the hand'wheel G is actuated wit a' convenient speed until the stress of ultimate tenacity. is attained. The enetrating distance of the die correspon sto the nature or resistance of the tested material; it may t be read on 'a scale H. The beginning of the rupture is observed from the operators seat by means of a mirror M; It is convenient to provide also a scale S on the hand wheel G in order tomeasure the tension of an interposed spring F, which tension corresponds to the requisite strain for producing the cone shaped hollow and corresponds to the resistance of the material.

When the metal sheet is not out into a disk, no remaining strip is left between the ring R and the holder 0. In this case the and the holder C according to Fig. 3. With this object in view the ring R is conveniently removable. The holder is brought near the metal sheet in such a manner that a constant play, for any thickness of metal sheets is provided, in order that it ma freely extend under theaction of the die. %Vhen graduat- ,metal sheet is inserted between the matrix B ing the scale";'account is taken of the amount of play, which is deduced from the distance between the holder and the matrix.

Having now fully described my said inp bearings provided on said frame, axially in line with each other, a matrix fitting one of said bearings, means provided in the second bearing and separately moving to and fro in said bearing with respect to said matrix for maintaining the metal sheet to be tested and for exerting on saidmetal sheet the re- .quired testing pressure, said latter means having a part spaced from the matrix to permit the metal sheet to have play in the direction 'of the axis of the apparatus whatever may be the thickness of said sheet.

2. An apparatus for testing the resistance to compressive and tensile strains of metal t sheets or plates comprising a frame, two

bearings provided on said frame and axially in line with each other, a matrix fitting one of said bearings, the second bearing having inner threads, a hollow, inwardly and outwardly threadedsh-eet holder holdingthe sheet to be tested against the matrix during the testing process, and ei'igaging the threads of said bearing, a hand wheel for actuating said holder, the outer edge of said holder having a circular cut, the adjacent edge of the matrix having a corresponding cut, a ring loosely and removably mounted in the groove formed by both said cuts for cutting the metal sheet in two portions, the first one formed by a disk shaped plate, the second annular portion beingmaintained in its original position between said ring and said holder during the testing process, the front, holding surface of said sheet holder having an annular recess to provide play for said disk shaped metal sheet when engaged between said holder and said matrix, a central peripherically threaded die engagingthp inner threads of said concentrically disposed holder, a hand wheel for actuating said centrally disposed die, for extending the metal sheet maintained between said matrix and said holder, an axially directed scale for measuring the axial displacements of said die with respect to the metal sheet to be tested, a coil spring between the die controlling hand wheel and a fixed part of the apparatus in order to measure the strain exerted by said die onto the metal sheet to be tested, a corresponding scale on said hand wheel and a mirror provided at the rear end of said frame in order to allow theoperator placed at the opposite end to discern the rupture of the metal sheet to be tested.

3. In a machine of the class described, the combination of a frame, two alined hearings on the frame, a'matrix mounted in one of the bearings, the other said bearing being internally threaded, an element operating in the threaded bearing and cotiperating with the matrix to confine a plate being tested, said element having threads on its circumference and formed with a central threaded opening, a die on the end of a threaded stem mounted in the" central threaded opening in the aforesaid element, and a hand piece on the threaded stem to operate the die in the matrix.

4. A machine of the class described, comprising a hollow matrix, means for loosely holding a plate against the surface of the hollow matrix, a part of said means having a threadedopeniug in alinementwith the hollow matrix, a threaded stem operating in the threaded opening and having on its end a die to force the metal into said matrix, a hand'wheel on the threaded stem, and an indicator and scale to indicate the movement of the die. i

5'. The process of measuring the drawing value of ductile metal, which consists in loosely yet firmly holding the said metal between annular supports during the testing operation, whereby the said ductile metal. between the supports is allowed to evenly flow as a result of axial pressure exerted upon it, gradually applying such pressure thereto by a pressure exegting means until fracture of themetal is obtained. and measuring the distance of the travel of the press ing means.

(5. A process for testing ductile metal for tenacity and ductility, which consists in loosely yet firmly holding the said metal between annular supports during thetesting operation whereby the said ductile metal between the supports is allowed to evenly flow as a result of axial pressure exerted upon it and gradually applying such pressure in measured intensity until fracture is obtained.

7. The process of measuring the drawing value of ductile metal, which consists in loosely yet firmly holding the said metal between annular supports during the testing operation, whereby the said ductile metal between the supports is allowed to evenly flow as a result of axial pressure exerted upon it, gradually applying such pressure thereto until fracture of the metal is obtained and measuring the resulting axial displacement of the metal.

Signed at New York city in the county of New York and State of New York, this ninth day of December, A. 1)., 1916;"

ABRAHAM MARTHINIUS iaucnsrr.

Witnesses; 7

WV. J. MACDONALD, S. RYAN.

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