US2499135A - Yield strength tester - Google Patents

Description

Feb, 28, 1950 G. R. ECKSTEIN YIELD STRENGTH TESTER 3 sheets-s e t 1 Filed May 16, 1946 mil... 6,

, INVENTOR I GEOJRGERT CK$TEIN E TORNEY Q. r\ w w o 9 0. o 0 a 5 7 2 9 1 a 7 a .2 0 a Figs Feb. 28, 1950 ca. R. ECKSTEIN YIELD STRENGTH TESTER 3 shets sheet 2 Filed May 16 1946 lNVENTOR GEORGE/Z ECKS TE/N BY 9/? w M ck ATTORNEY Feb. 28, 1950 G. R. ECKSTEIN 2,499,135

' YIELD STRENGTH TESTER Filed May 16, 1946 3 Sheets-Sheet 5 0 IO 4050 B0 90 I 270 360 0 IO 20 3040 50 -60 70 so I60 270 360 [Li 9 INVENTOR GEORGE/2 fc/rs TE/N ATTO-RNEY Patented Feb. 28, 1950 UNITED STATES PATENT OFFICE YIELD STRENGTH, TESTER George R. Eckstein, Bridgeport, Conm, assignor to Remington Arms Company, Inc., Bridgeport, Conn., a corporation. of Delaware.

Application May 16, 1946, Serial'No. 670,156

14 Claims. 1

This invention relates to testing means for comparing the physical characteristics of materials of construction and has a particular application-to the testing of certain metallic materials such as are used in cartridge case manufacture. The results obtained by the use of this invention may beclosely correlated with the yield strength of the particular material.

In consideration of the-problem of control of materials for cartridge case manufacture, it should be borne inmind that a cartridge case is a hollow substantially cylindrical body adapted to be chambered in a gun barrel and to have its head backed" up by a breech block or bolt. The head is generally axially pierced to receive a primer which is securedtherein by a friction fit or other means requiring close maintenance of the dimensionsof the primer pocket. Although the internal pressures to which the case issubjected are very high, ultimate tensile strength of the cartridge caseis not the most material factor in. view of the fact that the chamber and breech structure closely back up the case. It is, however, of great importance that the material be of such a nature that. it can-assumethe loads due to high internal pressures: without: suffering permanent, or non-elastic, deformation.

If the cartridge case suffers non-elastic de.- formation under the load of chamber pressure, it may stickinthechamber or. produce aprim'er pocket leak. The latter isof great significance because of the. destructive. erosive elfects'which may be attendant uponsuch leakage.

The most important factor to be considered is the. yield strength of the. material which may be defined as thatloading per unit: area at which elastic properties. are lost and the material suffers a permanent; deformation fromwhich it'will not recover on relaxation of the load. Another common definition of the yield point is that value.

of pressure per'unit area at which deformation ceases to be directly proportional to stress and increases rapidly with little or no further increase in stress. The commonly accepted method of. making such a test is by a tensiletest on a standard bar. This test is. obviously a destructive test and not applicable to the testing of finished articles of manufacture.

There are many non-destructive indentation methods in practical use by industry for material control purposes, such as the, Brinell, Vickers, Rockwell, and Knoop tests. These tests, however, yield and empiricalvalueof hardness based on such a number of. undetermined factors that. no one can say withcertainty just what. the hard.-

' deformation.

been shown. that; items having: widely different yield strengths. maybeselected from. a group of items showing identical hardness as judged. by BrinellgoryRockwell tests.

The nature of certain cartridge cases and they effect ofv improper alloysor only slightly improper heat treatment thereonis. such that every fin.- ished casemust; bechecked individually to insure thatiit. hasadequate yieldstrength if severe firing casualties.are.to.be.avoided.. Any: such testto be capable of. practical use must; be non-destructive and. must. be. capable of; being applied to. every case produced-without interrupting. the regular flow: of production The direct object... of. this invention is to provide a non-destructive machine for determining whether a given workpiece will be permanently deformed when subjected to a predetermined stress.

It isanother object of this invention to provide" a machine capable of readily ascertaining in a non-destructive manner whether a given workpiece equals or exceeds a predetermined minimum yield strength;

It is-a further object to providea machinecapable' of production line usage for determining that the yield strength of workpieces, for example,

small arms cartridge cases, is adequate to properly' resist the stresses applied in normal usage of the item.

This invention contemplates accomplishing these. objects byapplying apredetermined unit pressure: substantially equal to' the minimum yield strength desired to a selected uniform area of the workpiece and then gauging the workpiece to determine whether it has suffered any permanent If; the workpiece has sufiered'i a material amount, of" permanent deformation, its yield strengthis toolow and itmay be rejected. On. the. other hand. if the yield. strength of the workpiece equalsor exceeds. the predetermined minimum, it. will have suffered little. or no deformation, and will not. havebeen harmed by imposition. of the test. Since the most critical area of. a cartridge. case is its head, it iscontemplatedthat the partifiular embodiment shown will relate to the application of the invention to that section of a cartridge case.

As the discussion of the invention proceeds, it will become obvious that similar methods may be applied to many other articles of manufacture which present surfaces accessible to the application of unit pressure equal to the desired minimum yield strength, and allow for gauging of those surfaces to determine whether there has been any material permanent deformation.

The exact nature of the invention, as well as other objects and advantages thereof, will be more readily apparent after consideration of a detailed description referring to the appended drawings in which:

Fig. 1 is a perspective view of the machine from the left front with safety guards removed.

Fig. 2 is a top plan view of the machine.

Fig. 3 is an elevational view from the right hand side, using Fig. 2 as a reference for directions.

Fig. 4 is an enlarged partial vertical cross-sectional view through the pressure applying anvils, the cartridge case being shown in dotted lines.

Fig. 5 is a perspective view of the end of one of the anvils.

Fig. 6 is a developed view of the drum feed cam.

Fig. 7 is a developed view of the load applying cam properly oriented with respect to Fig. 5 to show the point in the sequence at which the load is applied.

Fig. 8 is a vertical sectional view on the line 8-8 of Fig. 2.

Referring to the drawing by characters of reference, it will be noted that the particular embodiment shown comprises a main frame I, and a side frame 2, these frame members being maintained in spaced parallel relation to each other by lateral frame members 3. Journaled in suitable bearings in the main frame and the side frame is the shaft 4 which may be rotated by any convenient means such as a belt 5 and a motor 6.

Feeding Secured on and rotable with the shaft 4 are the drum cam I which controls the feeding stroke, the feed pulley 8, and the weight cam 9. A feed belt I!) passes around the pulley 8 and an idler II, the upper run of the belt being substantially horizontal. Guide rails 12 define a feed channel bottomed by the belt in which cartridges may be placed by suitable means in head-down position and along which they will be fed to the testing apparatus per se. Further travel along the belt is obstructed at a point in alignment with the end of the feed finger l3 which may carry an auxiliary body support finger l4 engageable with the body of the cases.

Slidably supported on the lateral frame members is the feed finger carrier l5 which is provided with a follower l6 riding on the edge of the drum cam 1 and a spring I! constantly urging the follower into engagement with the cam. Figure 6 shows a developed view of the drum cam with feed finger carrier displacements as ordinates plotted against degrees of shaft rotation, the maximum displacementbeing that at which the feed finger is retracted to the greatest extent against the urging of the spring. As the shaft rotates, the cam follower will ride down the cam allowing the feed finger to be advanced by the spring and strip the leading cartridge from the feed channel. It will be noted that the cam is formed with a valley at l8 to allow for a slight retraction of the feed finger away from contact all with the cartridge. Immediately following this retraction, the feed finger remains stationary as the yield strength load is imposed by means to be presently described. Further rotation of the shaft allows the spring to carry the cam follower down to the bottom of the final valley I9 of the cam, advancing the feed finger to feed the cartridge to the gauging members. After the cam follower passes through the valley [9 on the cam, it is retracted as the cam follower rides up the hump on the cam into position to start a new cycle.

Load application As noted above, the feed finger l3 presents the cartridges successively to the station for applying the test load and allows them to remain in that position while the load is being applied. At the loadingstation a stationary anvil 20 projects slightly into the testing channel 2| in positionto engage the rim of the cartridge head as shown in Fig. 4. A slidable anvil 22 is provided in opposition to the stationary anvil and is adapted to be engaged by the short arm 23 on the lever 24. The lever 24 is pivotally carried on a shaft 25 attached to the frame I and has a long arm 26 on which an adjustably mounted weight 21 is carried. A bracket 28 on the long arm 26 provides a journal for the follower roll 29 which rides on the surface of the weight applying cam 9. As the main shaft is rotated, the arm is supported by the cam 9 until the follower rides down the smooth uniform incline into the valley 30 of the weight cam 9. During the interval in which the arm is supported by the cam the sliding anvil 22 will not project into the test channel 2| but as the long arm 26 swings downwardly the short arm 23 will engage the anvil 22, moving it into engagement with the rim of the cartridge case. The size of the weight 21, its position on the lever arm 26, the length of the short arm 23, and the dimensions of the fiat contacting faces 20a and 22a of the anvils 2|] and 22 are so chosen that the loading per unit area of the anvil faces will be substantially equal to the desired minimum value of yield strength. Fig. 5 shows in detail the relationship of the face 20a to the anvil 20. The face 22a on the anvil 22 is of similar size and is a mirror image thereof. The gradual application of the load assures that the final result wil not be complicated by impact or acceleration problems. Further rotation of the main shaft lifts the long arm 26 and removes the load from the anvil 22. Figures 6 and 7 are vertically aligned in order that it may be clearly seen that the test load is gradually applied and that it is applied during the time in-v terval that the feed finger is at rest.

It will be noted that the flat faces 20a and 22a of the anvils engage opposite points on the rim adjacent the extractor cannelure of the cartridge case and that, if the head has suffered any material amount of permanent deformation, a burr will have been raised in the extractor cannelure. It will be evident, from the elementary mechanical definition of yield strength, that if the pressure per unit area on the contacting faces of the anvils exceeds the yield strength of the particular workpiece, there will be considerable permanent deformation. In the event that a cartridge with a thin head is presented to the testing operation, the area presented to the anvils will be smaller and the'burr correspondingly greater, having a compensatory effect in the gauging operation to be next described.

green st Gauging As has been previously noted, the feed finger |3,:after relaxation of the testing. load on the anvils, presents the cartridge case toya gauging member to: determine whether the rim has suf-- fered any non-elastic deformation. The ganging set-up includes a composite base block 3| which is slidably mounted on guide rods 32 to provide a gauging channel 33: in lateral and vertical alignment with the testing channel 2|. Gauge blocks 34 are mounted on the base block to provide gauging fingers 35 extending into the gauging channel in position to engage the extractor cannelure on the" heads of the cartridge.

cases as they are successively presented. Between the opposed end: faces ofthe gauging fingers the diameter of the extractor cannelure may be checked although such a check is immaterial to this invention. The thickness of the rim defined by the base of the head and the wall of the extractor cannelure is checked between the bottom faces of the gauge fingers 35 and the top face 36 of the composite block 3|. Since the cartridge is pushed directly from a position between the loading anvils tothe gauging fingers, it will be obvious that the area gauged will be that to which the load was applied. If

. the thickness of. the: head is excessive, either by reason of improper machining or as a result of permanent deformation between the testing anvils, the head will not pass through the gauging fingers and the base'block 3| will be displaced laterally on the guiderods 32. Mounted on the baseblock 3| is the stop finger 3'! which has the dual function of blocking the feed channel by a portion 38 permitting the feed finger to pick up a case when the gauge block is in proper position and which also provides a portion 39 blocking the feed channel inadvance of the feed finger when the gauge blocks have been displaced. Obviously the feed finger itself blocks the feed channel during its feeding stroke. In the event that the case gauges properly, it will pass through the gauge fingers without resistance and may drop into a tote box or conveyor for transfer to further operations.

In the event of displacement of the gauging block by a reject round, the feed finger will oscillate idly until an operator removes the reject and replaces the gauge block in proper position. Removal of the reject round is accomplished simply by twisting the case to bring an undeformed section of the head into alignment with the gauge fingers or by pushing it back toward the anvils and allowing it to drop through the gap between the gauge block and the anvil supporting part of the frame. The gauge blocks are reset by pushing the base block back into contact with the anvil supporting part of the frame. Obviously rejection and resetting could be made automatic without departing from the invention, but in view of the fact that the reject frequency is generally low, applicants installation did not justify the added expense which would have been entailed thereby.

Summary of operation Cartridges are placed either manually or by known automatic means on the feed belt in head-down, aligned relationship and fed down the feed channel by frictional engagement of the belt with the face of the head. -As the leading cartridge contacts the portion 38 of the stop finger, it is stopped thereby. Onnthe next strokev of the feed finger i3 its tip and the auxiliary body' support I4 engage the leading cartridge and feed it from the feed channel into the testing channel 2| between the load applying anvils 20 and 22. The feed cam follower I6 drops into the valley i8 and then retracts the feed finger to an idle position out of contact with the case.

During this. idle interval the weight applying cam 9 comes into a position in which its support is gradually removed from the weight arm 24. The'lowering of the free end of the weight arm causes the sliding anvil 22 to move in and apply a loading to the areas of the rim engaged between the anvils predetermined to be of the same magnitude per unit of contacted area as the desired minimum value of yield strength. The slope of the cam is such that the load is applied smoothly and does not represent a test under impact con-' dit'ionsor include false values due to acceleration. The weight cam 9 then picks up the arm removing the load from the anvils and the feed- 35 which allow it to pass without resistance if the head has been undeformed. If the rimhas been non-elastically deformed to any material extent, the gauge fingers 35 will not pass the burrs thereon, the base block 3| will be laterally displaced, and the stop finger 37 will prevent the feeding of the following cartridges.

The feed finger I3 will then oscillate idly untilthe deformed case has been removed from the gaugefingers either by twisting itor byrevers mg itsmotion and dropping it through between the gauge block and the frame. The gauge block 3| may then bereset, clearing the stop finger from the feed channel to allow cartridges to again be fed to the testing channel.

The test applied is distinct from that applied by the so-called' hardness testers in that an acceptable workpiece passes the test without suf fering any permanent deformation, or at most a negligible amount of such deformation. The hardness testers utilize a pointed or spherical indentor and always make a major permanent deformation or indentation. Their comparative readings are based either on evaluation of the loads necessary to produce a predetermined standard depth or diameter of deformation or on the extent of deformation produced by a predetermined standard loading. Because of the continuously variable area as the indentor penetrates, there is no uniformity of stress over the area and the results are obscured by the progressive work hardening which inevitably takes" place.

I It will be realized that this invention may be practised with apparatus of other than the exact construction here disclosed. It is intended, therefore, that this invention is to be considered as limited only by the scope of the claims appended hereto.

I claim:

1. A testing machine comprising a frame; guide means 'on the frame defining a testing channel; a fixed anvil mounted in the guide means with its face projecting slightly into the testing channel; a second anvil slidably mounted in the guide means in. opposition to the first anvil for projection into the testing channel; a driven shaft journaled in the frame; a feed cam on the shaft;

a feed finger mounted for sliding movement along the testing channel, spring-urged and restrained by the feed cam to position an article to be tested between the anvil faces, permit it to dwell there, and give it a further feeding movement before retraction to a starting position; load applying means operating in timed relation to the feed finger to apply a predetermined compressive load to the movable anvil during the interval in which the article dwells between the anvil faces; and article gauging means in alignment with the testing channel to receive the article during said further feeding movement and determine whether the article has suffered material permanent deformation as a result of the application of the test load.

2. A testing machine comprising a frame; a driven shaft journaled in the frame; a pulley on the shaft; a feed belt passing around the pulley and supported by an idler on the frame; guide means on the frame defining a feed channel adapted to receive articles to be tested bottomed by the upper run of the belt; guide blocks on the frame defining a test channel at right angles to the feed channel; a fixed anvil secured at one side of the test channel and projecting slightly thereinto; a second anvil slidably mounted on the other side of the test channel and adapted to be projected thereinto in opposition to the first anvil; a drum feed cam on the shaft; a feed finger mounted for sliding movement along the line of the test channel, spring-urged and provided with a follower riding on the feed cam, the cam allowing the feed finger to advance to move an article from the feed channel to a'position between the anvils, permit it to dwell there, and give it a further feeding movement before retraction to a starting position; load applying means operating in timed relation to the feed cam to apply a predetermined compressive load to the article through the slidable anvil during the interval in which the article dwells between the anvil faces; and article gauging means in alignment with the testing chamiel to receive the article during said further feeding movement and determine whether the article has suffered material permanent deformation as a result of the application of the test load.

3. A testing machine comprising a frame; a driven shaft journaled in the frame; a pulley on the shaft; a feed belt passing around the pulley and supported by an idler on the frame; guide means on the frame defining a feed channel adapted to receive articles to be tested bottomed by the upper run of the belt; guide blocks on the frame defining a test channel at right angles to the feed channel; a fixed anvil secured at one side of the test channel and projecting slightly thereinto; a second anvil slidably mounted on the other side of the test channel and adapted to be projected thereinto in opposition to the first anvil; a drum feed cam on the shaft; a feed finger mounted for sliding movement along the line of the test channel, spring-urged and provided with a follower riding on the feed cam, the cam allowing the feed finger to advance to move an article from the feed channel to a position between the anvils, permit it to dwell there, and give it a further feeding movement before retraction to a starting position; a lever swingably mounted on the frame and having a short arm in contact with the outer end of the movable anvil and a relatively longer arm carrying a weight; a test cam on the shaft engaging the test cam follower to support the longer arm, the cam gradually removing that support during the interval in which the article dwells between the anvils and reassuming such support before said further feeding movement; article gauging means slidably mounted in alignment with the testing channel to receive the article during said further feeding movement, said gauging means being adapted to freely pass an undeformed article and to be displaced laterally by an article which has suffered a material permanent deformation; and a stop arm on said gauging means adapted to close the feed channel when the gauging means has been laterally displaced.

4. A testing machine for metallic cartridge cases comprising a frame; a driven shaft journaled in the frame; a feed pulley on the shaft and a feed belt carried thereon; guide means on the frame defining a feed channel bottomed by the belt on which the cartridges to be tested may be placed in head-down relationship; guide blocks on the frame defining a testing channel at substantially a right angle to the feed channel; means to feed the cartridges singly and in succession through the feed channel with an intermediate stop at a station therein; opposed anvils at said station adapted to engage the extractor rim of the case; means to cause at least one of the anvils to move relative to the other to apply a predetermined unit compressive load to the rim during the intermediate stop; head thickness gauging means movably mounted in alignment with the test channeladapted to receive and pass an undeformed head as the case is fed from said station and to be displaced by a materially deformed head which will not pass the gauging means; and a stop finger actuated by displacement of the head thickness gauge to prevent the feeding of following cartridges to the test station.

5. A testing machine for metallic cartridge cases comprising a frame; a driven shaft journaled in the frame; a feed pulley on the shaft and a feed belt carried thereon; guide means on the frame defining a feed channel bottomed by the belt along which the cartridges to be tested may be carried in head-down position; guide blocks on the frame defining a testing channel at substantially a right angle to the feed channel; a feed cam on the driven shaft and a feed member controlled thereby adapted to feed cartridges singly and in succession from the feed channel through the testing channel with an intermediate stop at a testing station in the latter channel; a fixed anvil and a movable anvil opposed to each other on opposite sides of the testing channel and adapted to engage diametrically opposite portions of the extractor rim of a cartridge case during its stop at the testing channel; a testing cam on the driven shaft and means controlled thereby to apply a predetermined force to the movable anvil during the interval in which the case is stopped; and head thickness gauging means in prolongation of the testing channel adapted to receive and freely pass an undeformed rim as the case is fed from the testing station and means actuated by presentation of a case having a rim materially deformed by the test loading to stop the feeding of other cartridges to the testing channel.

6. Testing apparatus comprising means to apply a predetermined uniformly divided pressure per unit area to a selected area of the article to be tested; actuating means for said pressure applying means; gauge means responsive to permanent deformation of said selected area arranged to receive said article and determine whether the article has suffered a material amount of permanent deformation as the result of the application of the test pressure; means for transferring an-ar ticle fromsaid pressure applying means to said' gauge' means; and a common operator constructed and arranged for actuating said pressure applying means and said article transferring means in a timed sequence.

'7. Testing apparatus comprising an anvil having a flat face adapted to be brought into contact with the part to be tested over the entire area of said flat face; means to apply a load of predetermined magnitude to the anvil whereby a predetermined pressure per unit area will be applied to the area in contact with the flat face; gauge means responsive to permanent deformation of said contacted area to receive said article and determine whether the article has suffered a material amount of non-elastic deformation as the result of the application of the test load; means for transferring an article from said anvil 10 loading means to apply a predetermined total load to the movable anvil and then to remove said load; article gauging means to receive said article responsive to permanent deformation of the area contacted by said anvil face, said actuating means for the feedmember being so constructed and arranged that further operation to said gauge means; and a common operator and arranged to decrease the relative distance between the anvil faces and. thereby apply a compression load of uniformly distributed predetermined magnitude per unit area to selected areas of the article therebetween; gauging means responsive to permanent deformation of said selected areas to receive said article and determine whether the article has suffered a material amount of permanent deformation as the result of the application of the test load; means for transferring an article from between said anvil faces to said gauging means; and a common operator constructed and arranged for actuating said loading means and said article transferring means in a timed sequence.

9. Testing apparatus comprising a fixed anvil having a flat face; a second anvil opposed to and movable toward the first having a flat face equal in area and opposed to the fiat face of said first anvil; means to position an article to be tested between the opposed faces of said anvils; loading means of predetermined magnitude engaging the movable anvil to move it toward the fixed anvil and apply a uniformly distributed compressive stress of predetermined magnitude to the article; means to remove the load from the anvil; gauge means toreceive said article responsive to permanent deformation of the areas contacted by said anvil faces; transfer means constructed and arranged to move the article in predetermined orientation to the gauge means to determine whether the article has suffered a material amount of permanent deformation; and common operator means constructed and arranged for actuating said loading means and said transfer means in a timed sequence.

10. Testing apparatus comprising a fixed anvil having a fiat face; a second anvil having a flat face, said second anvil being movably mounted with its face in opposition to that of the first anvil; a feed member; means to actuate the feed member to position an article to be tested between the opposed faces; loading means of predetermined magnitude engageable with the movable anvil; support means sequentially removable from and replaceable beneath the thereof removes the article from between the anvils and conveys the article in predetermined orientation to the gauging means to determine whether the article has suffered a material amount of permanent deformation as a result of application of the test load; and a common operator constructed and arranged to drive the feed member actuating means and said support means in predetermined timed sequence.

11. A testing machine comprising a fixed anvil having a flatface; a second anvil having-a flat face movably mounted with its flat face in opposition to that of the first anvil; a common operator; loading means actuated 'by said common operator and constructed and arranged to apply to and to remove from the movable anvil an anvil projecting load of predetermined magnitude; article gauging means to receive an article which has been positioned between said anvil faces and responsive to permanent deformation thereof; a feed member for sequentially positioning an article between said anvils and transferring said article from said anvil position to said gauging means; and control means actuated by said'common operator for effecting a yielding advance of said feed member from a retired position and a positive return thereof to retired position comprising a feeding spring and a limiting cam associated therewith and arranged to sequentially resiliently advance said feed member to position an article between said anvils, positively retain said article against retrograde movement from such position during movement of said movable anvil, further resilientlyadvance said feed member to place said article in said gauging means, and positively restore said feed member to retired position.

12. A testing machine comprising a feed channel; a testing station; a gauging station; feed means constructed and arranged to successively strip articles to be tested from the feed channel, position them for an interval at the testing station, and present them to the gauging station; means at the testing station to apply a predetermined magnitude of uniformly distributed pressure per unit area to selected areas of the article during its pause at the testing station; gauging means at the gauging station responsive to permanent deformation of said selected areas constructed and arranged to receive said article and detect any article which has suffered a material amount of permanent deformation; an element associated with said gauging means constructed and arranged to be moved by the response of said gauging means to the presentation of a deformed article; and blocking means constructed and arranged to be actuated by movement of said element to block the removal of further articles from the feed channel.

13. A testing machine comprising a frame; an anvil having a fiat face fixed to the frame; a second anvil slidably mounted on the frame having a flat face in opposition to the flat face of said first anvil; a driven shaft journaled on the frame; a feed cam rotatable with the shaft; a spring-urged feed finger slidably mounted and having a member engaged with said feed cam and controlled in the extent of spring-urged 11 movement thereby, said finger and said feed cam being constructed and arranged to position an article between the anvil faces and withdraw slightly therefrom; a load cam on said shaft; loading means controlled by the load cam constructed and arranged to apply aload of predetermined magnitude to and to remove said load from the movable anvil while the article is positioned between the anvils; and article gauging means responsive to permanent deformation of the portion of said article contacted by said anvil faces constructed in prolongation of the line of movement of the feed finger, a further portion of the feed cam being constructed and arranged to withdraw opposition to further spring-urged movement of the feed finger adequate in extent to remove the article from between the anvils and to present it to the gauging station to determine whether the article has suffered a material amount of permanent deformation as a result of the application of the test load.

14. A testing machine comprising a frame; guide means on the frame defining a testing channel; a fixed anvil secured at one side of the testing channel and projecting slightly thereinto; a second anvil slidabl mounted at the other side of the testing channel and adapted to be projected thereinto in opposition to the first anvil, said second anvil having a flat face normal to the line of projection of said anvil; an operator; cyclically operating feed means actuated by the operator and adapted to position an article to be tested between the anvils; loading means actuated by the operator in timed relation to the feed means to apply to and remove from the movable anvil an anvil projecting load of predetermined mag nitude; and article gauging means responsive to permanent deformation of the portion of said article contacted by the anvil face forming a prolongation of the testing channel, said feed means being constructed and arranged to have a further cyclic movement to transfer the article into the gauging means after the operation of the loading means to determine whether the article has suffered a material amount of permanent deformation as a result of the application of the load.

GEORGE R. ECKSTEIN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,367,191 Leckie Feb. 1, 1921 1,408,554 Widney Mar. '7, 1922 2,286,286 Laystrom et al. June 16, 1942 2,356,236 Gagne, Jr Aug. 22, 1944 2,364,129 Catlin et al Dec. 5, 1944 2,364,263 Yablonsky Dec. 5, 1944 2,450,003 Klipsch Sept. 28, 1948

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