US1499546A - Testing machine - Google Patents

Description

Jun 1 1924. MWMG .A. E. OXLEY TESTING MACHINE Filed Feb. 13 1924 lllllllllllllllllllll flllllllllllllllllllll illllllflll! atented .lully l, W24.

THUR ERNEST OXLEY, or DIDsBURY, NANcREsTER, ENGLAND, AssIeNoR To T BRITISH coTToN INDUSTRY RESEAIWH AssoorATIoN, or mnsRURY, Nome- TER, ENG AND.

TESTING MACHINE.

Application filed February 13, 1924. Serial No. 692,618.

Z all whom it may concern.

Be it known that- I, ARTHUR ERNEST Ox- LEY, a subject of the King of Great Britain, residing in Didsbury, Manchester; in the county. of Lancaster and Kingdom of England, have invented certain new and useful Improvements in Testing Machines, of which the following is a specification.

This invention relates to a machine for testing threads and the like.

According to'the present invention cyclical variation of stress is applied to a length of thread suspended in a machine. Further by this invention means are provided to prevent the rotation of the thread about its axis to cause untwisting of the same.

This invention also includes a method. of recording automatically the extension of the thread in conjunction with the automatic recording of the number of cycles of the applied stress.

In one form of construction of the machine the threads are connected to cranks at one end and carry loadin weights at the other, the load being such t at the maximum loading on the thread which occurs with the crank at one extreme position relatively to the thread will always be less than thebreaking load of the thread. The numbers of variation of stress applied in this manner-previous to the rupture of the thread is a measure of the strength of the thread when submitted to cyclical varia tions of stress. 4

scribed with reference to the accompanying drawings, in which;

Figure 1 shows a machine for mechanically causing a cyclical stress.

Figure 2 1s a detail View.

Figure 3 is a diagram of the'cut out circuit. I Figure 4 is a detail of the out.

Referring to Figs. 1 and 2 a device' for submitting threads to cyclical variations of stress is shown. Mounted on a suitable frame work 44 are a series of bearings 45 in which is mounted a crank shaft 46 carrying cranks 47 the shaft 46 bein driven in any suitable manner as shown drive 48. The cranks 47 are connected by a connecting rod 49 to slides 50 working in guides 51 mounted on a suitable girder 52.

Attached to the slides 50 are screw grips electrical cut The invention is more particularly dewith the lower edge of the cams by springs y the belt I 53 supporting the threads 1, the lower end of which are attached to lower grips 54 supporting weights 55 through a- ,bifilar suspension 56 comprising a pair of cords passing through vertical lass or the like tubes 57 attached to a cross cam 58 by adjustable clamps 59. The bifilar suspension prevents any untwisting action liable to occur in the thread.

Mounted below the member 58 is a catch board 60 clamped at any desired distance to allow for a s ecimen of any desired length. The catch oard 60 carries electrical contacts 61 arranged below the Wei hts 55 so that if a specimen breaks its weig t falls upon the corresponding stud 61 to complete an electric circuit and thus to stop the ma' chine.

Arranged opposite the movement of the weights are graduated scales 64 so that any extension of the thread may be recorded by reading the lowest position of the weight at intervals. I Alternatively, the scales may be arranged opposite the point of attachment of the. thread to the bifilar member 56, thus avoiding any possibility of the reading including any extension of the bifilar members 56.

It is evident that as the cranks rotate the weights 55 are caused to move vertically upwardsand downwards with a motion which is-approximately simple harmonic and by their inertia produces a cyclical variation of tension in the specimen 1.

Instead of the system of cranks and slides just described to roduce the simple harmonic motion of t e weights, cams may be employed to give any desired typeof motion, the connecting rods being held in contact or supported by gravity from the upper edge. Alternatively the system of cranks shown in Fig. 1 may be retained but the cranks driven at a non-uniform angular velocity by means of a cam driving mechanism oreccentric pulley. In this manner the motion given to each individual specimen ma be varied to produce differences in the cyclical stress.

Figs. 3 and 4 show a convenient cut out mechanism.

Referring to Fig. 3 it will be seen that the motor M is connected across the batte' A throu h the contact B and correspon ing mova 1e armature contact 0, so that on the 110 insertion of the switch the motor is su plied with current in the usual manner. (In the depression of the stud 61 the relay circuit is complete causin the battery D to energize the coils E of t e electro-magnet F in this manner pulling the contact arm 0 and breaking the contact between B and C thereby stoppingthe motor.

Fig. 4 shows thestud 61 in detail which is maintained in an elevated position above the corresponding contact plates 62 by means of a s ring 63.

I declaret at what I claim is 1. In a machine for testing threads or the like the combination of means to. suspend said thread means to apply a cyclical variation of tensile stress axially of said thread, and means to prevent the rotation of said thread about its axis tending to untwist the same.

2. In a machine for testing threads the combination of means to suspend said thread by one end thereof, a weight attached to the end of said thread remote from said suspending means, means to move said suspending means through a cyclical path to produce variation in the stress imparted to said thread, and means to prevent the untwisting of said thread about its axis.

3. In a machine for testing threads the combination ofi a weight, attached to one end of the thread, suspension means for the other end of said thread, a rotary crank connected to said suspension means, .means to rotate said crank, and means to prevent the untwisting of said thread.

4. In a machine for testing threads the combination of a weight attached to one end of the thread, suspension means for the other end of said thread, a rotating crank, a-connecting rod connected to said crank at one end and at the other to said suspension means, a guide for said connecting rod and means to prevent untwisting of said thread.

5. In amachine'for testing threads the combination of a weight attached to one end of the thread, suspension means for the other end of said thread, a rotating crank, a connecting rod connected to said crank at one end and at the other to said suspension means, means forming a slide way to guide said connecting rod, means to prevent untwisting of said thread, and

means to sto said rotating crank automatically on the reakage of a thread.

6. In a machine for testing threads the combination of suspension means for said thread a rotating crank, a rod connecting said crank to said suspension means, a guide for said latter end of said rod in order to give reciprocating motion to said suspension means, a weight, bifilar connections between said weight and the end of said thread remote from said suspension means, and means to retain said bifilar connections in the same relative positions in order to prevent untwisting of' the thread.

7. In a machine for testing threads the combination of suspension means for said thread a rotating crank, a rod connecting said crank to said suspension means, a guide for said latter end of said rod, a weight, bifilar connections between said weight and theend of said thread remote from said suspension means, and a stationary sleeve encircling each element of said bifilar connection.

8.. In a machine for testing threads the combination of suspension means for said thread a rotatin crank, a rod connecting said crank to sai suspension means, a guide for said latter end of said rod, a weight, bifilar connections between said weight and vthe end of said thread remote from said suspension means, a stationary sleeve encircling each element of said bifilar connection, and an electric cut out arranged beneath said weight and ada ted to stop the rotation of said crank on t e falling of said weight through the breakage of said thread.

9. In a. machine for testing threads the combination of suspension means for said threads a rotating crank means to give said crank non-uniform angular motion a rod connecting said crank to said suspension means, a guide for said latter end of said rod in order to give reciprocating motion to said suspension means, a weight, bifilar connections between said weight and the end of said thread remote from said suspension means and means to retain said bifilar connections in the same relative positions in order to prevent untwisting of the thread.

In witness whereof, I have hereunto signed my name this 28 day of January 1924, in the presence of two subscribin witnesses.

ARTHUR ERNEST XLEY.

Witnesses:

' JOHN WILLIAMSON,

WILLIAM LENNON.

Images