US2677959A - Testing apparatus for tube frame brakes - Google Patents

Description

May 11, 1954 N. COREY 2,677,959

TESTING APPARATUS FOR TUBE FRAME BRAKES Filed May 11, 1955 3 Sheets-Sheet l a: n g g -May 11, 1954 N. COREY TESTING APPARATUS FOR TUBE FRAME BRAKES Filed May 11, 1953 5 Sheets-Sheet 2 I I l W J l I INVEN TOR. /V/6//04A.S COREY 1! TTORNE I May 11, 1954 N. COREY TESTING APPARATUS FOR TUBE FRAME BRAKES 3 Sheets-Sheet 5 Filed May 11, 1955 INVENTOR. N/(HOLAS CORE y ATTORNEY I Patented May 11, 1954 UNITED STATES ENT FFICE TESTING APPARATUS FOR TUBE FRAME BRAKES Application May 11, 1953, Serial No. 353,953

3 Claims. 1

This invention relates to tube frames for Axminster looms and more particularly to a device for testing and adjusting the brakes on such tube frames.

An object is to provide novel and improved means for measuring the brake drag for adjusting purposes.

Another object is to ensure identical braking on all of the tube frame spools so that uniform yarn feed is obtained.

Various other objects and advantages will be apparent as the nature of the invention is more fully disclosed.

[he nature of the invention will be better understood from the following description, taken in connection with the accompanying drawings in which specific embodiments thereof have been set forth for purposes of illustration.

In the drawings:

Fig. 1 is a side elevation of a brake testing device embodying the invention with parts broken away.

Fig. 2 is a section taken on the line 2-2 of Fig. 1.

Fig. 3 is a side elevation of a testing apparatus illustrating a further embodiment of the invention;

Fig. 4 is an end elevation of the apparatus of Fig. 3; and

Fig. 5 is a schematic diagram illustrating a still further embodiment.

Referring to the drawings more in detail, the invention is shown in Figs. 1 and 2 as applied to an apparatus for testing the brakes on an AX- minster tube frame N3 of the usual construction, having a base I I rectangular in section extending along the entire length of the tube frame and carrying a set of yarn tubes it. The frame is provided at its ends with brackets 4 to receive the Axminster loom spools and with clips it for attachment to the conveyor chains. The base I l carries brake shoes IS on spring arms H at each end in a position to engage the end drums of the loom spools which are supported in the brackets In the usual construction the friction drag of the brake shoes It is adjusted by bending the spring arms ii and it is desirable to have the friction drag on all of the spools as nearly uniform as possible so that the yarn feeds evenly from all of the spoolsv When the yarn is exhausted from one spool the loom is stopped and. the remaining yarn stripped from the other spools. Hence a substantial yarn loss takes place if one of the spools becomes exhausted prematurely, due, for example, to a light brake, which permits an excess amount of yarn to be drawn off at each operation.

In accordance with the present invention, the brake testing apparatus comprises a base 26 carrying a frame 28 which supports a sleeve bearing 2i in which a pin 22 is slidably mounted.

The pin 22 carries a block 23 having a recess 24 therein positioned to receive and support the end of the base if of the tube frame It which is to be tested. A similar fixed block 29 carries the other end of the tube frame.

The frame 23 supports a bracket 25 having bearings 25 in which a shaft 21 is journalled. The shaft 2'! carries a drum in in a position corresponding to that of the brake drum of a loom spool in the tube frame it and adapted to be engaged by the brake shoe it when the tube frame is in raised position as shown in Fig. 1.

The bracket 25 also supports arms 3| having bearings 32 in which hubs 33 on the housing 34 of an electric motor 35 are journalled. ihe motor 35 may be of the type having a built-in reduction gearing terminating in a drive shaft 35 carrying a belt pulley 31. The belt pulley 3i carries a belt 38 driving a pulley 319 on the shaft 2i. Obviously, the belt drive can be replaced by a gear drive if desired.

The motor housing 3 3 is free to rotate in the bearings 32 and carries an arm Ml connected by a link 4! to a dynamometer 62 having a pointer 43 and a scale it which may be graduated to read in units of torque.

The pin 22 and block 23 are normally in a lower position and are adapted to be elevated by a lever 46 pivoted at 49 to the frame 28 and engaging a pin 50 on the block 23. An adjustable stop 5! on the frame 23 engages the lever 48 to limit its upward movement to a predetermined position in which the brake drum 39 has the same relationship with respect to the tube frame 50 as the brake drum on the usual loom spool.

A snap switch 52 on the lever #38 is normally closed but is provided with a plunger 53 which engages a stop 54 on the frame 28 to open the switch when the lever 48 is in its lower position. The switch 52 is connected by leads not shown to control the operation of the motor 35.

In the operation of this apparatus, one of the tube frames N3 of a set is inserted in the blocks 23 and 29. The lever 48 is then raised to bring the brake shoe 1% of the tube frame H3 into engagement with the brake drum 30. Release of the switch 52 also starts the motor 35 so that the drum 30 is driven at a given speed. The drag of the shoe it on the drum 38 opposes the rotation of the motor shaft 36 and the reaction on the motor housing 34 causes the housing to turn and exert a pull on the dynamometer 42 which thus indicates the torque required to turn the drum 30 against the drag of the brake shoe it. The spring arm ll carrying the brake shoe is then adjusted if necessary to produce a predetermined reading on the dynamometer scale.

The tube frame is is then reversed and the brake it at the other end is similarly adjusted. In the case of long tube frames, it may be convenient to make the block 28 movable and to duplicate the testing apparatus at the other end of the frame so that the brakes at both ends can be adjusted simultaneously but independently by diiierent operators.

The above operations are repeated for each tube frame of the set and all brakes are set to exert the same drag so that, when used in the loom, a uniform yarn feed is obtained from all of the spools.

In the embodiment of Figs. 3 and 4, the tube frame it block 23, lever 53 and cooperating parts are similar to the corresponding parts of Figs. 1 and 2 and have been given the same reference characters. In this form, however, the motor 69 is of the type having a shaft geared to drive an output shaft 6! extending 90 to the motor shaft. The output shaft 6! is journalled in bearings t2 in arms 63 carried by the frame 23 and carries a gear 54 meshing with a gear 65 on the shaft 65 which corresponds to the shaft 27 of Fig. 2 and is journalled in bearings 6'3 and 58 in an arm 69 and in one of the arms 63 respectively. The shaft 66 carries a brake drum as as in the form in Figs. 1 and 2.

The motor housing carries a bracket it in which a rod H adjustably secured by a set screw 13. At one end the rod H carries a counterweight M to balance the weight of the motor and at the other end the rod H is connected by a link 15 to a dynamometer 16, similar to the dynamometer 42 above described.

In this embodiment, the torque of the motor causes the motor housing to turn about the axis of the shaft 6i with a force which is indicated by the dynamometer reading.

In a further embodiment, the motor 35 of Figs. 1 and 2 or the motor 68 of Figs. 3 and 4 may be fixed against rotation and supplied with a constant voltage by a line 89 (Fig. 5) with an am- 4''. meter 8| connected to indicate the power drawn by the motor. The motor is preferably of the D. C. shunt wound type in which the current drawn is proportional to the load.

With this type of motor the drag of the brake is indicated by the reading of the ammeter 8|. The measurements and adjustments are otherwise carried out in the manner described above.

Various other adaptations will be apparent to a person skilled in the art.

What is claimed is:

1. An apparatus for testing the brakes on an Axminster tube frame carrying a brake shoe, said apparatus comprising a rotatable brake drum, a motor driving said brake drum, a support to carry said tube frame, means for shifting said support relative to said rotating brake drum to bring said brake shoe into frictional engagement with said brake drum whereby said brake shoe exerts a drag on said drum, and indicator means indicating the driving torque of said motor required to overcome said drag.

2. An apparatus for testing the brakes on an Axminster tube frame carrying a brake shoe, said apparatus comprising a rotatable brake drum, a motor driving said brake drum, a movable support to carry said tube frame, means for shifting said support from a retracted position to a predetermined position in which said brake shoe exerts a drag on said brake drum, and indicator means indicating the driving torque of said motor required to overcome said drag.

3. An apparatus as set forth in claim 2 in which said support is mounted for vertical movement between retracted and advanced positions, a lever is connected to control said movement, stop means to limit the movement of said lever, and switch means responsive to the movement of said lever to energize said motor when said lever is shifted to advanced position.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,942,920 Fawkes Jan. 9, 1934 2,314,139 Garrity Mar. 16, 1943 FOREIGN PATENTS Number Country Date 893.225 France Jan. 24, 1944

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