US3648495A

US3648495A - Individually driven drawing blocks intended for storage-type wire drawing machines

Info

Publication number: US3648495A
Application number: US852208A
Authority: US
Inventors: Karl Lars Gunner Rabe; Karl Sune Ingemar Hanaeus
Original assignee: ARBOGA MEKANISKA VERKSTAD AB
Current assignee: ARBOGA MEKANISKA VERKSTAD AB
Priority date: 1968-08-30
Filing date: 1969-08-22
Publication date: 1972-03-14
Anticipated expiration: 1989-03-14
Also published as: FR2016692A1; DE1943814A1; GB1225106A; SE325852B; JPS496032B1

Abstract

There is provided an arrangement for automatically maintaining the amount of wire stored on individually driven drawing blocks in wire drawing machines at a constant level within preselected operating conditions, the arrangement comprising a friction arm and friction elements adapted to urge at a preselected pressure a wire guiding roller or like member against the wire as it is unwound from the block, and wherein means are provided for connecting the friction arm to a device which registers deviations in the angular position of the arm and transmits a signal in response to said deviations to the motor driving the block, thereby to change the speed at which the motor and/or the block rotates.

Description

aEe at al.

1 1 Mall, 114, 1972 [54] lNDlWllDlUAlLlLE DRIVEN DRAWING DEDEES llNTENDED ED STDAGE- TYPE WERE DAWllNlG MAEHINEE [72] Inventors: r1 Lars Gunner Eallre, Arboga; Earl Sune lngernar lllanaeus, Smedjebacken,

21 Appl. No.: 852,208

[30] Eoreign Application Priority Data Aug. 30, 1968 Sweden ..1 1685/1968 [52] U.S. Cl ..72/110, 72/288, 72/289 [51] Int. Cl E211 37/00, 13210 1/02 [58] Field all Search ..242/78, 78.6, 129, 82; 72/6, 72/8, 9, 10, 17, 288, 289, 274, 425

[56] Eelierenees Cited UNITED STATES PATENTS 2,664,250 12/1953 Friedman ..242/78 2,272,192 2/1942 Fisher ..72/10 3,133,629 5/ 1964 Bruestle ..72/l0 1,025,588 5/1912 ODonnell et a1 ..72/289 1,482,860 2/1924 Oslund ..72/289 2,213,344 9/1940 Johnson ..72/289 1,915,722 6/1933 Earnshaw .72/10 1,316,935 9/1919 Barron ....72/10 3,459,024 8/1969 Richards... ..72/289 1,534,998 4/1925 Vaughn ...72/l0 FOREIGN PATENTS OR APPLICATIONS 63,173 9/1924 Sweden 211,377 10/1963 Sweden Primary Examiner-Charles W. Lanham Assistant Examiner-Michael Keenan Att0rneyCushman, Darby & Cushman [57] ABSTRACT There is provided an arrangement for automatically maintaining the amount of wire stored on individually driven drawing blocks in wire drawing machines at a constant level within preselected operating conditions, the arrangement comprising a friction arm and friction elements adapted to urge at a preselected pressure a wire guiding roller or like member against the wire as it is unwound from the block, and wherein means are provided for connecting the friction arm to a device which registers deviations in the angular position of the arm and transmits a signal in response to said deviations to the motor driving the block, thereby to change the speed at which the motor and/or the block rotates.

Patented March 14, 1972 3,648,495

2 Sheets-Sheet l Patented March 14, 1972 3,648,495

2 Sheehs-Sheet 2 1\\\| l Q My l.

INVENTORS ATTORNEYS The present invention relates to an arrangement in individually driven drawing blocks adapted for use in storage type wire drawing machines in which friction arms slip against the block so as to guide the wire stored on the block as it is unwound therefrom.

Storage type wire drawing machines, which work with considerable quantities of wire woundstoredon the block, have become very popular, partly because they are relatively inexpensive, and partly because the wire is cooled in a superior fashion to other types of machines which is of great ad vantage in all wire manufacturing processes. The machines may either operate continuously, wherewith they comprise a plurality of drawing blocks arranged in groups, or they may comprise separate units. As the wire stored on the block is unwound therefrom, it is guided by a friction arm arranged at the top of the block, there being one such arm for each block, and which serves to maintain tension in the wire as it is unwo jjlind, to prevent snarling, etc.

To these ends, the friction arms are pivotally mounted in the blocks and provided with adjustable, spring biased friction ele ments arranged between the arm and the block. By means of a suitable contacting force between the friction elements, a guide roller or like member rotatably mounted on the outer end of the friction am can be held against the wire unwound from the rotating block with a frictional force created by the slip between the friction elements, this force maintaining tension in the wire and being equalized by the resistance exerted by the wire. Provided that the amount of wire on the block or the height of the wire stored thereon is constant, the arm will remain stationary. Any change from the amount of wire on the block, however, will cause the arm to swing so as to maintain the balance between the frictional force and the resistance of the wire. This causes the wire unwound from the block to be twisted about its longitudinal axis to an extent in relation to the magnitude of the movement of the arm which is undesirable since the quality of the wire is impaired as a result thereof. Moreover, an increase or decrease in the height to which the wire is stored on the block causes a corresponding degree of variation in the cooling of the wire, which also impairs the quality of the wire. In the case of the machines categorized in the aforegoing in which the drawing blocks are driven individually, it is true that these disadvantages can be circumvented by supervising the height of the wire on the block and the movements effected by the arms, and when necessary stopping and starting the separate block units to regulate the height of said wire on the block. This method, however, is unsatisfactory since it does not fully eliminate the possibility of twisting and uneven cooling of the wire, besides requiring constant and careful supervision of the machine.

Accordingly, the object of the invention is to provide in individually driven drawing blocks of the aforementioned type an arrangement which functions automatically and completely eliminates the possibility of both twisting and uneven cooling of the wire as well as reducing the amount of necessary supervision. An arrangement constructed in accordance with the invention, which completely fulfills this object and has an advantageous effect on production since it obviates the necessity of stopping and starting the separate drawing block units to regulate the height of the wire stored on the block, is mainly characterized in that the friction arm is pivotally mounted in the block by means of a spindle or like member secured to the arm, the spindle also being connected to an angle registering device which upon deviation of the friction arm from its selected position transmits a signal corresponding to the magnitude of the swing effected by the arm to cause a corresponding compensating change in the speed of the block drive motor and/or the block. The spindle or like member is adapted to extend within the drive shaft of the block, the shaft therefore being of tubular construction. The end of the spindle remote from the friction arm projects beyond the tubular driving shaft of the block and is there connected with the angle registering device.

The invention will now be described with reference to an embodiment thereof illustrated diagrammatically in the accompanying drawings, further characteristic features of the invention being disclosed in conjunction therewith.

FIG. 1 shows a vertical section through a separately driven storage-type drawing block provided with the arrangement of the invention.

FIG. 2 is an enlarged detail view with parts broken away showing the friction arm 12 and friction surfaces 113 and M and the connection between the spindle and friction arm.

For the sake of clarity, all details normally associated with the drawing block unit but unessential to the invention have been omitted.

As will be seen from the drawing, the rotatable drawing block I is mounted on a vertical shaft 2 which is journaled in the stand 3, for example at the positions indicated by arrows 4 and 5. The manner in which the shaft is journaled to the stand is not essential to the invention and will not be described in detail. The shaft 2, to which the block 1 is attached by any appropriate means, supports a block drive worm gear 6 which meshes with a worm gear 7 mounted in the stand 3. The worm gear 7 is turned by means of a DC motor (not shown) intended to drive the unit individually.

In addition to the drawing block 1 and the DC motor (not shown), the stand 3 also supports a table 8 and a standard 9 which in turn supports a rotatable but non-driven pulley or roller 10 above the block 1. The pulley It) serves as a guide pulley for the wire as it is unwound from the block I. The wire during its passage from the block to the pulley passes around a rotatable but nondriven guide roller or pulley 11 mounted on one end of a known friction arm 12 which is of the aforementioned type and which is pivotally mounted in the block 1, said end of the friction arm 12 projecting radially outwards from said block. Between the arm 12 and the block ll there is an adjustable, spring biassed, as at 26 and 28, friction element so arranged that a friction surface 13 fixed on the arm 12 is in adjustable contact with a friction surface 14 fixed on the block. The friction element is connected to arm 112 through the spring biassed pins in

members

26 and 28, one of which is shown at 30 which is provided with a projection fitting into a hole formed in the friction element on the side thereof opposite the friction surface 13. In this way, the arm 12 is driven by the block in the aforementioned manner as a result of the friction occurring between the

surfaces

13 and 14. The magnitude of the friction between the surfaces can be adjusted by conventional setting means 15. In accordance with the aforegoing, the friction am 12 and the guide roller 11 as sociated therewith are used during operation of the unit with the assistance of the frictional force set between the arm and the block to maintain a suitable tension in the wire as it is unwound, whereupon the mentioned state of equilibrium is obtained between the frictional force and the resistance of the wire, and the arm remains stationary while sliding against the block at a constant quantity of wire on the block or a constant height of wire stored on the block. Since any change in the amount of wire on the block or in the height of the wire stored thereon is a result of a difference in the amount of wire taken up by the block and the amount of wire unwound therefrom, all differences between wire take up and unwinding will be ac companied by a change in the quantity of the wire taken up on the block, whereupon the friction arm 12 moves in one direction or the other to maintain the state of equilibrium. There is consequently obtained a particularly sensitive automatic balancing effect.

In accordance with the invention, the state of equilibrium is not solely used to maintain a convenient tension in the wire as it is unwound from the block as was previously the case, but also to maintain automatically the amount of wire taken up on the block constant, whereby twisting and uneven cooling of the wire is prevented and the necessity of machine inspection reduced. To these ends, the pivoting movement of arm 12 is used during operation of the unit to control the speed at which the block rotates. In this way, a reduction in the amount of wirethe amount stored-on the block can be automatically compensated by increasing the speed of the block, and vice versa. For this purpose, the pivoting movement of the friction arm is transferred to a suitable device which registers the angle through which the arm moves and sends a signal corresponding to the magnitude of this angle to the speed regulating means of the motor (not shown), whereupon said speed regulating means as a result thereof cause a change in the rotation speed of the block which corresponds with the signal and which compensates for the outswing of the friction arm, thereby maintaining a constant amount of wire wound on the block.

In the exemplary embodiment, the friction arm 12 is pivotally mounted to the block 1 by means of a spindle 16 and firmly attached to one end of said spindle. The spindle 16 is arranged for movement within the drive shaft 2 of the block, the shaft 2 being tubular to enable it to accommodate the spindle. The end 17 of the spindle l6 remote from the friction arm 12 projects beyond the drive shaft 2 at the lower end thereof and is there connected with an angle registering device 18.

In the illustrated embodiment of the invention, the angle registering device 18 is of the electrical transducer type. This device is mounted so that one active part thereof is attached to the spindle, while its other active part is attached to a portion of the stand 3, for example to the stationary bearing block 19.

In addition to an electrical transducer, the angle registering device may be in the fon'n of a turn type potentiometer, for example, or any other suitable device capable of transmitting a signal corresponding to a change in the position of the friction arm 12 to change the speed of the motor and/or the block in response to the deflection of the arm. It is therefore also possible within the scope of the invention to use a mechanical angle registering means to regulate the speed at which the block rotates, and thus a mechanical variator may also be considered in this respect.

The arrangement of the invention is fully automatic and is intended to be connected only when the drawing block unit has reached its normal operational state with respect to rotative speed, quantity of wire located thereon and the selected position of the friction arm, this position being indicated by a check lamp 20 mounted on the table 8. The actual operational speed is set manually by the machine operators by means of a control knob 21 on the table 8. When the selected conditions of operational state have been realized, an electric switch 22 on table 8 is activated which connects up'the arrangement of the invention, whereupon said arrangement takes control of the machine and ensures that the friction arm 12 remains in the selected position by immediately compensating any tendency of the arm to deviate from this position with the necessary changes in block speed, in either direction.

The arrangement of the invention is not restricted to the described and illustrated embodiment, but can be modified within the scope of the following claims.

What we claim is:

l. A control apparatus for a motor driven drawing block for use in storage type wire drawing machines comprising a tubular shaft in said block having a spindle member movably disposed therein, said spindle member being securely attached at one end to a friction arm and at its other end to an angle registering device so that swinging movement of said friction arm relative to said block will be sensed by said angle registering device, said device having an output which varies in response to movements of said friction arm, said output being connected to the motor of said block whereby the speed of said motor will vary in response to changes in said output, said block having a friction surface in adjustable engagement with said friction arm whereby said arm will be driven by said block.

2. The control apparatus according to claim 1, characterized in that the angle registering means is of the electrical type and comprises a transducer.

3. An arrangement according to claim 5, characterized in that one active part of the angle registering means is connected to the spindle or like member, while the other active part thereof is connected to the block stand 4. The control apparatus according to claim 1, characterized in that the angle registering means is of the mechanical type and comprises a mechanical variator.

5. The control apparatus according to claim 1, characterized in that the angle registering means is of the electrical type and comprises a turn type potentiometer.

Claims

1. A control apparatus for a motor driven drawing block for use in storage type wire drawing machines comprising a tubular shaft in said block having a spindle member movably disposed therein, said spindle member being securely attached at one end to a friction arm and at its other end to an angle registering device so that swinging movement of said friction arm relative to said block will be sensed by said angle registering device, said device having an output which varies in response to movements of said friction arm, said output being connected to the motor of said block whereby the speed of said motor will vary in response to changes in said output, said block having a friction surface in adjustable engagement with said friction arm whereby said arm will be driven by said block.

3. An arrangement according to claim 5, characterized in that one active part of the angle registering means is connected to the spindle or like member, while the other active part thereof is connected to the block stand.

4. The control apparatus according to claim 1, characterized in that the angle registering means is of the mechanical type and comprises a mechanical variator.