US2557330A - Casing stripping machine safety device - Google Patents

Description

`une 19, 1951 J. P. wlLGER cAsING STEIPPING MACHINE SAFETY DEVICE Filed Aug. 13, 1948 Patented June 19, 1951 CASING STRIPPING MACHINE SAFETY DEVICE Jerome P. Wilger, IChicago, Ill., assigner to Swift & Company, Chicago, Ill., a corporation of Illincis Application August 13, 1948, Serial No. 44,147

This invention relates to a safety device for casing stripping machines in which opposed rotating rolls present an ever present danger to persons feeding material to the machine.

In the operation of casing stripping machines of the type herein referred to, a pair of superimposed parallel rolls are employed in casing stripping operations. A relatively narrow endless belt conveyor carries the casings into the space between the rolls, and casings are placed upon said conveyor manually. There is an ever present danger of the trapping of the hands or clothingof a person feeding the conveyor between the rolls, which could result in serious injury. The present invention proposes to provide a safety shield in front of the rolls and in close proximity to the path of movement of the conveyor belt and casings. The safety shield is preferably pivoted for swinging movement toward and from the rolls so that it will be engaged by the hands of an operator if the hands approach the rolls too closely. Pivotal movement of the shield in such a manner is caused to actuate a switch to immediately stop the motor employed in driving the rolls.

It is an object of this invention to provide a safety device of the nature set forth that is Very simple in construction yet highly efficient and foolproof in operation.

It is further an object of this invention to provide a safety device of the type referred to that is extremely sensitive and yet of unusually rugged construction.

It is still a further object of this invention to provide such a safety device that is stable against accidental displacement.

Further objects and advantages will become apparent to those skilled in the art as the description proceeds with reference to the accompanying drawings, wherein:

Fig. 1 is a front elevational view of a casing stripping machine equipped with the safety device of the present invention and showing the driving means schematically; Y

Fig. 2 is an end view of the machine of Fig.` 1 as viewed from the right end thereof; and

Fig. 3 is an isometric View of the safety shield of the present invention.

Casing stripping machines of the type upon whichit is contemplated the present invention be applied generally comprise a supporting frame having end members I and 2 upon which a pair of parallel rolls 3 and 4 are rotatably mounted by means of shafts 6 and I journalled in the end members I and 2. Adjacent ends of the Claims. (Cl. 1532-130) 2 shafts 6 and 'I carry meshing gears 8 and 9 of equal size affixed thereto and the shaft 'I additionally has a sprocket wheel It keyed or otherwise rigidly xed thereon. TheY sprocket wheel Ill is driven by a sprocket chain I I from a second sprocket wheel I2. The sprocket wheel I2 i's mounted on the output shaft I3 of ajworm type speed reducer I4 driven by a motor I5. By the arrangement described, it will be seen' that the rolls 3 and 4 are caused to rotate in opposite directions at equal speeds whereby their opposed surfaces move in the same direction at substantially the same peripheral speed. The rolls 3 and 4 are sometimes covered by canvas Orburlap covers I6 and Il. Each of the rolls 3 and 4 is likewise provided with a peripheral groove|8. A conveyor belt (not shown) extends generally horizontally into the groove I8 between the rolls; and casings are placed upon the conveyor belt by gravity or by an operator generally stationed immediately in front of the rolls. Theendless conveyor belt is caused to move into thfe rolls to thereby feed the casings thereto. As--is apparent, without the guardit would be `possible for an employee attending the stripper machine to place his or her hands too near the rotating rolls 3 and 4 which could result in thehands being drawn into the rolls and seriously injured.- v

The safety device' of the present invention comprises a forwardly extending bracket 20 on each of the end members of the machine and each bracket carries, adjacent its outermost end, a bushing or other suitable bearing means 2l. preferably forwardly of the upper roll.3. A shaft 22 is rotatably mounted in the aligned bearings 2| and has rigidly attachedthereto ashield in dicated generally as 23. The shield comprises an upwardly and rearwardly extending portion 24, a downwardly extending portion or-apron 25, and rearwardly extending endportions 26. The upper edge of the portion 24 and the lower edge of the portion 25 are preferably provided with rolled edges 2l and 28 to eliminate sharp or ragged portions. The downwardly extendingportion 25 of the shield 23 extends to al point below the space between the rolls 3 and 4 and consequently below the path of travel of the endless belt referred to and the casing thereon. The portion 25 of the shield is therefore provided with a cutout portion 29 of such con-l figuration and extent as to clear the endless conveyor belt and the casings thereon and allow the latter to move into the rolls without inter ference from the shield.

Adjacent one end of the shaft 22 and preferably between an end portion 26 and the adjacent bearing 2|, a bracket 30 is rigidly mounted. The bracket 38 carries a switch mechanism 3|, to be described later. At the end of the shaft 22 opposite from the switch 3| 'the said shaft is provided with a collar 32 rigidly affixed theren. The collar 32 is provided with an inwardly extending notch 33 at its periphery, said notch having a generally radial shoulder portion 34. A pawlV or detent 35 is pivoted to the end member 2, as at 36, and is of such length that its free end may be moved into positionto engage the notch 33 in the collar 32. An end surface of the pawl 35 abuts the shoulder 34 of the collar 32 and acts as a stop to prevent rotation of the shaft 22 in a clockwise direction as seen in Fig. 2, beyond the position where the shoulder 34 is so engaged. The shaft 22 and shield 23 may, however, rotate ,freely in the opposite direction.

Adjacent the collar 32 shaft 22 is provided with a sleeve 3'I having a radial arm 38 extending therefrom. A counterweight 3S is longitudinally adjustable along the arm 38 and may be xed in adjusted position by means of a set screw or the like. The sleeve 3l may also be angularly adjusted about the shaft 22 and may be fixed in adjusted position by means of a set screw or the like. The counterweight 39 and stop means 34-35 mutually act to urge the shaft 22 and the shields 23 to a xed position in which the switch 3|, previously referred to, is in a predetermined position. It will be seen that by the arrangement just described vibrations in the vicinity of the machine or accidental displacement of the shield 23 through small angles will not result in actuation of switch 3| and, yet, the said shield is free to be displaced by a sufficient force to effect stopping ofthe machine.

The switch 3| is preferably of a mercury type wherein tilting of the switch beyond a normal position causes a pool of mercury to flow therein and make or break an electrical circuit between spaced contacts. The switch 3| is arrangedin an electrical circuit including the conductors indicated generally at 40. The conductors 40 are connected to a plugging switch 4| which in turn is connected to an extension of the high speed shaft 42 of the speed reducing unit I4. The plugging switch 4I Ais of a known type and need not be described in detail, When the switch 3| is tilted beyond the positions shown in the drawings the circuit therethrough will be broken and the plugging switch 4| will thereby become conditioned to effect breaking of the power circuit to the motor I and a reversal of Vthe current in the motor until the motor is instantaneously stopped.

If desired the machine described may be provided with means (not shown) to effect quick and easy lifting of the top roll 3 in the event an operator becomes caught between the said rolls. Such means could readily be made automatically operable upon actuation of the shield 23 and/or the switch 3 I.

Clearly the safety device described is not limited to use with the specic machine shown but may be readily adapted for use with any machine in which material or work pieces are manually fed to moving parts.

It will be apparent to those skilled in the art that various changes and modications may be made without departing from the spirit of the invention. It is intended that the invention be limited only by the scope of the appended claims.

I claim:

1. A casing stripping machine comprising a frame, a pair of elongated superposed rolls journalled on said frame; means for driving said rolls to receive and squeeze material therebetween; a shield pivoted to said frame on an axis generally parallel to the axes of said rolls, said axes being spaced forwardly of the upper of said rolls, said shield being of substantially the same length as said rolls and comprising a portion extending downwardly from said axis having a lowermost edge forwardly of and spaced from the lower of said rolls, a portion extending upwardly and rearwardly from said axis, and end portions extending transversely to said axis and rearwardly toward the ends of said rolls, the downwardly extending portion of said shield having a cut-away portion through which material may be conveyed to a position between said rolls; a switch for controlling said driving means, shoulder means connected to said shield for movement therewith; stop means on said frame cooperating with said shoulder means to prevent movement of the upwardly portion of said shield towards said rolls while permitting pivotal movement of the shield in the reverse direction, substantially all of said shield being between said axis and said rolls whereby the weight of said shield tends to hold the shoulder means in engagement with said stop means; and means whereby pivotal movement of said shield in said reverse direction will actuate said switch to stop said power means.

2. In a casing stripping machine the combination of a frame; a pair of superposed stripping rolls; electrically operated power means to drive said rolls; and a safety device to prevent an operator from accidentally getting an appendage caught between the rolls, said safety device including a pvotally mounted shield positioned about the space in front of the line of contact between the rolls and obstructing substantially all access to said line from the front, sides and top thereof, means to limit the pivotal movement of the upper portion of said shield towards said rolls, and electric switch means electrically connected to said power means to effect stopping of said rolls in response to a pivotal movement of said shield in the opposite direction.

3. In a casing stripping machine the combination of a vertical frame; a pair of superposed stripping rolls journaled in said frame in contact with each other; electrically operated powermeans to drive said rolls; and a safety device to prevent an operator from accidentally getting an appendage caught between the rolls, said safety device including a pair of brackets projecting to one side of said frame and positioned to either end of said rolls, a shield between said brackets and pvotally mounted therefrom along a line spaced from said side of said frame and rolls and above the line of contact between the rolls, said shield having an apron extending downwardly from said pivotal line to below said line of contact, said shield also having an upper inclosure member extending toward the upper of said superposed rolls from said pivotal line, stop means to limit the pivotal movement of said upper member of the shield toward said rolls, and electrical switch means electrically connected to said power means to eifect stopping of said rolls in response to a pivotal movement of said shield in the opposite direction.

4. A safety device for a casing stripping machine comprising a frame, a pair of elongated superposed rolls journalled on said frame, and

means for driving said rolls to receive and squeeze material therebetween, said device including a shield pivoted to said frame on an axis generally parallel to the axes of said rolls, said axis being spaced forwardly of the upper of said rolls, said shield being of substantially the same length as said rolls and comprising a portion extending downwardly from said axis having a lowermost edge forwardly of and spaced from the lower of said rolls, a portion extending upwardly and rearwardly from said axis, and end portions extending transversely to said axis and rearwardly toward the ends of said rolls, the downwardly extending portion of said shield having a cutaway portion through which material may be conveyed to a position between said rolls, a switch for controlling said driving means, shoulder means connected to said shield for movement therewith, stop means on said frame connecting with said shoulder means to prevent movement of the upwardly portion of said shield towards said rolls while permitting pivotal movement of the shield in the reverse direction, substantially all of said shield being between said axis and said rolls whereby the weight of said shield tends to hold the shoulder means in engagement with said stop means, and means whereby pivotal movement of said shield in said reverse direction will actuate said switch to stop said power means.

5. A safety device to prevent an operator from accidentally getting an appendage caught between the rolls of a casing stripping machine having a frame, a pair of superposed stripping rolls and electrically-operated power means to drive said rolls, said device including a pivotally mounted shield positioned about the space in front of the line of contact between the rolls and obstructing substantially all access to said line from the front, sides and top thereof, means to limit the pivotal movement of the upper portion of said shield towards said rolls, and electric switch means electrically connected to said power means to effect stopping of said rolls in response to a pivotal movement of said shield in the opposite direction.

JEROME P. WILGER.

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

UNITED STATES PATENTS Number Name Date Re. 22,574 Collins Dec. 5, 1944 1,220,620 Freeman Mar. 27, 1917 1,865,479 Mueller July 5, 1932 1,970,957 Erickson Aug. 21, 1934 2,102,154 Hill Dec. 14, 1937 2,166,410 `Jackson July 18, 1939 2,180,238 Hoke Nov. 14, 1939 2,381,671 Ladner Aug. 7, 1945

Images