US3060729A - Threading textile and similar machinery - Google Patents

Description

United States This invention is concerned with threading or piecingup mechanism for textile machinery, such as textile testing machinery of the type disclosed in United States Patent No. 2,442,150.

It is an object of the invention to provide a method of threading continuous lengths of thread and mechanism for this purpose. The term thread includes filaments, yarns, threads and ribbons.

According to the present invention, a method of threading a continuous length of thread through at least two elements comprises forming a continuous closed passage including said elements and drawing a free end of the thread along the passage by means of a current of fluid. The fluid may be air, a current of which may be produced by means of a venturi ejector at the outlet end of the passage.

United States Patent No. 2,442,150 described the testing of a textile thread by connecting a thread sample between a fixed clamp and a clamp mounted on a weighted carriage which is free to move on a normally horizontal track. During the test, the track is tilted to a gradually increasing angle so as gradually to increase the load on the thread to breaking point. A stylus mounted on the carriage moves across a platen linked to the track and draws a graph on the platen of the extension of the thread against the load applied to it.

The present invention lends itself readily to application to the machine according to said United States patent and to any other machine employing a substantially fixed and a movable clamp. By means of the present invention, the threading or piecing-up operation may be speeded up and furthermore that operation may be rendered automatic.

The invention also includes an apparatus for testing tensile properties of threads, comprising a substantially fixed clamp and a movable clamp, each of said clamps containing a continuous closed passage, which passages cooperate to form a single composite closed passage when the clamps are at their nearest proximate position, and means for producing a current of fluid in said single passage.

Preferably, the clamps of the testing mechanism are operated pneumatically or electrically. By employing the present invention, the whole operation of the machine may be rendered automatic, since automatic control of the steps other than the threading or piecing-up is already available. As a result, the threading of the sample, closing the clamps in succession, carrying out the test, restoring the track and carriage to their starting positions, removing the tested sample and repeating the whole sequence, including stopping the machine after a preselected number of tests, may take place Without the assistance of an operator. The test results may be recorded graphically by a stylus or numerically by means of an electro-magnetic typewriter, which latter may record the breaking load and extension at breakage of each test and automatically present the average at the end of the completed sequence of tests. A suitable device for detecting the breakage of the thread and setting the recording equipment in motion is described in our co-pending British specification No. 8914/58, United States Ser. No. 798,268, now Patent No. 3,029,347.

atent ice Apparatus according to the present invention for fitting to a yarn testing machine as shown in United States Patent No. 2,442,150 is shown diagrammatically in the accompanying drawing, which shows the arrangement of the clamps and threading device in part section.

FIGURE 1 is a diagrammatic cross sectional view of apparatus embodying the invention.

FIGURE 2 is a section taken on line IIII of FIG. 1.

A clamp 1 is fixed and a clamp 2 is carried by the moving carriage. The clamps are identical in construction, each being shown in section in the drawing. They consist essentially of a metal body provided with a U- shaped passage 3, 4 respectively, the turn in the passage embracing a transverse bollard 5, 6 which provides an anvil against which movable clamping members 7, 8 clamp the thread. The clamp members 7, 8 are connected by stirrups 9 and 10 to pneumatic cylinders 11, 12 mounted on top of the clamps 1 and 2. When air is admitted to the cylinders through inlets 13, 14, the stirrups are raised and the clamp jaws closed.

Clamping member 7 is fitted with pins 24 which move in slots 25 whereby the member 7 may be urged against the bollard 5 by the pneumatic cylinder 11.

When the movable clamp 2 is in position on its carriage on the machine, the arm of the passage 4 remote from the clamp member 8 is in line with the arm of the passage 3 remote from the clamp member 7. The stationary clamp 1 carries a sleeve or tube 15 coaxial with the aligned part of the passage 3 and projecting towards the clamp 2. As the clamp 2 strikes the end of this sleeve 15 each time the clamp returns to the threading up position, a resilient annular buffer piece 17 is provided on damp 2 with which the end of the sleeve 15 engages. The movable clamp 2 has a corresponding sleeve or tube 18 of smaller diameter which passes inside the sleeve 15 as the movable clamp 2 approaches the fixed clamp 1. In FIG. 1, the clamps are shown in the position in which they are at their nearest proximate positive in which threading can take place. In this position the tubes 15, 18 form a continuous closed passage passing between the clamps. The passages 3, 4 and tubes 15, 13 form a composite continuous passage of substantially constant cross-sectional area.

The other end of the passage 4 to that which runs into the tube 18 is provided with an inlet tube 19 for the yarn. To make a smooth entrance for the thread, this tube may be bell-mouthed. The other end of the passage 3 in clamp 1 to that which leads from the sleeve 15, is continued in a tube 20 which leads to a Waste tube 21.

At the junction of the tube 20 with the waste tube, a venturi passage 22 is provided which is supplied with compressed air at low pressure through an inlet 23.

In the position shown, due to the sealing efiect of the butter 17, if air is supplied :to the passage 22 through the inlet 23 it will draw a current of air through the tube 20, passage 3, tube 18, passage 4 and inlet 19. If an end of yarn is presented to the yarn inlet tube 19 and the clamps are open, this end of yarn will be drawn through the system so long as it is not restrained from entering the inlet tube 19. In practice, a measuring device is provided to release at each operation a length of yarn suitable for a test.

When the broken end of yarn from the previous test has been blown down the waste tube and the new end of yarn has been drawn through the clamps 2 and 1 to the extent permitted by the measuring device, clamp 2 is first closed, to be followed immediately by clamp 1, the tension in the yarn exerted by the air flow being suificient to simulate the small tension which would be applied by a human operator in normal circumstances.

Once the clamp 1 is closed, the drive for tilting the track is engaged and the test proceeds until the yarn breaks. When the yarn breaks, the carriage runs down the track till it strikes a buffer and in so doing operates a switch which acts to restore the track to a position just past the horizontal so that the carriage returns under gravity to its original position with the bufier 17 against the end of the sleeve 15. On its return, the carriage operates a further switch, opening the clamps and renewing the supply of compressed air to the nozzle 22.

What we claim is:

1. Apparatus for automatically threading a machine having a substantially 'fixed clamp and a separate movable clmp, means for moving said clamps toward each other, means for closing said clamps, and means for moving the clamps away from each other for testing tensile properties of threads, comprising a continuous closed passage of substantially constant cross sectional area within each of said clamps, each passage having an end axially aligned with, and facing an end of the passage in the other clamp, a tube projecting from said aligned end of one clamp, said tube having substantially the same internal cross sectional area as the passage within that clamp, and a similar tube projecting from the aligned end of the passage in the other clamp, said second tube having a larger internal cross sectional area than the external cross sectional area of the first tube, which tubes and passages form together a single closed passage when the clamps are most closely together, means at the remaining end of the closed passage in one clamp for receiving the thread, and means at the outlet end of the passage in the other clamp for producing a current of fluid in said single passage.

2. Apparatus for automatically threading a machine having a substantially fixed clamp and a separate movable clamp, means for moving said clamps toward each other,

means for closing said clamps, and means for moving the clamps away from each other for testing tensile properties of threads, each said clamp having a substantially fixed clamping member, a movable clamping member and a continuous passage of substantially constant cross sectional area, means defining an interconnecting passage between said clamping members, said interconnecting passage means comprising a first tube projecting from the first clamp in axial continuation of the passage therein, a second tube projecting from the second clamp in axial continuation of the passage therein, said first and second tubes being in axial alignment with each other and said first tube being so dimensioned as to project into the second tube when the clamps are brought into close proximate positions wherein said continuous passages and said interconnecting passage means form a composite continuous passage, means for passing a current of fluid through the composite continuous passage so formed whereby the end of a thread introducedto an inlet end of the composite passage is drawn through the passage.

References Cited in the tile of this patent UNITED STATES PATENTS 2,661,588 Griset et al Dec. 8, 1953 2,724,264 Dart et al "Nov. 22, 1955 2,724,957 Griset Nov. 29, 1955 2,875,609 Seney Mar. 3, 1959 2,881,906 Griset Apr. 14, 1959 FOREIGN PATENTS 666,506 Great Britain Feb. 13, 1952

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