US2733063A

US2733063A - Safety devices

Info

Publication number: US2733063A
Authority: US
Publication date: 1956-01-31
Anticipated expiration: 1973-01-31

Description

D. W. COREY SAFETY DEVICES Jan. 3l, 1956 5 Sheets-Sheet l Filed May 28, 1953 rl fllrllllllll [n ven for Donald h/ Corey @y fuir Aom /z/ 5 Sheets-Sheet 2 rwen Dona d h/.Ca

D. w. cREY SAFETY DEVICES N2 n Q L mpv w t O -i asf N. w MMF] ,www Z O O Z lud nw :4. O 006 Jan. 3l, 1956 Filed May 2a, 1955 Jan. 3l, 1956 D. w. coREY 2,733,063

SAFETY DEVICES Filed May 28, 1953 5 Sheets-Sheet 3 11u/enfor- Donald )f1/Corey 5?/ his Azomey @www Jan. 3l, 1956 Filed May 28. 1953 n. w. coRr-:Y 2,733,063

SAFETY DEVICES 5 Sheets-Sheet 4 MQW( D, W. COREY SAFETY DEVICES I Jan. 3l, 1956 5 Sheets-Sheet 5 Filed May 28, 1953 NJA* rgA A n Ipo@ www United States Patent SAFETY DEVICES Donald W. Corey, Beverly, Mass., assignor to United Shoe Machinery Corporation, Flemington, N. J., a corporation of New Jersey Application May 28, 1953, Serial No. 357,949 s Claims. (ci. 'zn- 57) This invention relates to safety devices, and more particularly to an improvement in the type of safety device utilized in conjunction with machines having a work treating zone and power driven feed rolls on both sides of the work treating zone. The present invention is an improvement on safety devices of the type disclosed in No. 2,701,463, grantedv February 8, 1955, in the names of Richard W. Daniels, J r. and John J. Maciejowski. The present invention is herein disclosed as being embodied in a leather treating machine ofthe type disclosed in United-States Letters Patent No. 2,663,179, granted December 22, 1953, in the names of Richard W. Daniels, Ir. and John J. Maciejowski but it is understood that in its broader aspects the invention is not limited to use with this particular machine. l

In that class of machines where a workpiece-is fed into a work treating zone by cooperatively mounted feed rolls and is later withdrawn from the Work treating zone by a pair of discharge rolls, considerable dii'lculties arise when a workpiece fails properly to pass through the work treating zone. If the operation of the machine is not immediately halted, considerable damage will be incurred by the work treating elements and the workpiece will likewise be damaged. In the above-mentioned Letters Patent No. 2,701,463 means are disclosed for preventing such damage when a workpiece becomes fouled in the work treating zone by automatically stopping the operation of the feed and discharge rolls. Also in that patent means are provided for reversing feed rolls and discharge rolls so that the fouled workpiece may be extricated from the machine. While this arrangement is satisfactory under some circumstances, it has certain disadvantages particularly in the extrication of the snarled workpiecevwhere the leading edge of the workpiece has become fouled when entering the work treating zone and while a previously-fed workpiece is still within the work treating zone or between the discharge rolls. The subject class of machines as exemplified in the above-mentioned Letters Patent utilizes a common drive for both the feed and discharge rolls to provide an economical and ellicient construction with this arrangement, when the work rolls are reversed to eXtricate the fouled workpiece the previously treated `workpiece is also fed back into the work treating zone. This results in the possibility of the prior fed workpiece being fouled in attempting to enter the work treating zone in a reversed direction or if the workpiece does enter the Work treating zone then it is processed a second time, which can also be undesirable. Furthermore there is a hazard 4to the worker at the rear of the machine in that he can be drawn into the discharge rolls.

It is an object of this invention to provide, in machines of the type herein disclosed, means for preventing a workpiece retained between the discharge rolls from being reintroduced into the work treating zone when the rolls are reversed to extricate a subsequently-introduced fouled workpiece.

The present invention is embodied in a leather compactiug machine of the type disclosed in the above-mentioned Letters Patent No. 2,663,179. The machine comprises a heavy fabricated base carrying certain of the operative elements of the machine and a pivotal head casting upon which other operative elements are mounted. Workpieces are fed between a pair of infeed rolls into a work treating zone comprising a pair of transversely mounted and reciprocating hammer bars which compress the workpiece against a series of yieldingly mounted anvils opposite said bars. To the rear of the work feeding zone is a pair of discharge rolls for carrying the workpieces from the work treating z'one.

More particularly' and in accordance with the various features of the present invention a detector bar is mounted within the work treating zone and adjacent to the infeed rolls. When a workpiece fails properly to pass through the work treating zone, the detector bar is raised thereby activating an electrical circuit provided with several relays for controlling the operation of the machine. Upon activation, the current to the windings of the electrical motor used as the power source for the feed rolls is reversed for a predetermined length of time thereby bringing the feed rolls to a sudden stop. The length of time which the reverse current is applied is controlled by a dash-pot arrangement which is adjusted preferably so that the reverse current is applied only long enough to bring the feed rolls to a quick stop. However, it may be adjusted so that reverse current is applied for a greater length of time so that the feed rolls will be automatically driven in reverse directions to withdraw a fouled workpiece from the machine. Preferably a Contact button is provided for the operator to control the feed rolls in reverse direction at his discretion to remove or extricate a fouled workpiece.

As a feature of the present invention a solenoid operated liuid valve is provided in the fluid system which raises and lowers the lower discharge rolls. When the electrical circuit is activated, a iluid valve is thereby reversed callsing ltwo fluid motors immediately to lower the lower discharge vroll from its operative position. With such an arrangement, when the direction of rotation of the feed rolls is reversed either manually or automatically, a prior fed workpiece lying between the discharge rolls is not fed back into the work treating zone while a subsequently fed workpiece is being extricated. If part of the first fed workpiece is still within the work treating zone it may be pulled therefrom by the operator at the rear of the machine even though the work rolls are turning in reverse directions since the lower discharge roll is in its inoperative position.

The above and other features of the invention including various novel ldetails of construction and combination of parts will now be more particularly described with reference to the accompanying drawings and pointed out in the claims.

ln the drawings,

Fig. l is a view in elevation of Vthe right side or end of I a machine in which the present invention is embodied, the feed rolls of the machine being placed in their ineffective or inoperative positions;

Fig. 2 is a view in elevation of the left side or end of the machine lshown in Fig. l, with certain portions being cut away for clarity and with the feed rolls in their effective or operative positions;

Fig. 3 is a view in rear elevation of the machine with certain parts omitted and others broken away to show internal details of construction;

Fig. 4 is a view in section drawn Ito a larger scale showing in greater detail certain elements shown in Fig. 2 with `the lower ldischarge roll in its inoperative position; and

Fig. 5 is an Yelectrical diagram showing suitable circuits for the operation of the machine and a schematic view of a uid system controlled by one of the electrical circuits. H

There is provided in the present machine a fabricated frame indicated generally by the reference character 10 (Figs. 1, 2 and 3) on which various working elements of the machine are mounted and a head casting 12 upon which other operative elements are mounted. An infeed shelf 14 provides a place for a workpiece to be spread out and supported as it is introduced between infeed rolls 16,

17 (Fig. 4). Beyond the

infeed rolls

16, 17 is a work treating zone indicated generally by the reference character 18 which extends to a pair of discharge rolls 20, 21. Within the work treating zone 18 is aV narrow passage defined by various guiding plates 22, two series of anvils 24 resiliently mounted transversely in the machine, and a hammer bar 26 opposite each series of anvils mounted for reciprocating movement in the frame 10.

A motor RM of standard three-phase construction (Fig. 5), not shown in Figs. 1-4, is provided for driving the

rolls

16, 17 and 20, 21. A sprocket 28 is secured (Fig. 2) to the shaft 30 of the motor RM and is con nected by a chain 32 to a sprocket 33 secured to a shaft 34 upon which the upper discharge roll 20 is mounted. The lower discharge roll 21 is driven at the same peripheral speed but in the opposite direction of rotation through a gear train consisting of the

gears

36, 38, 40 and 42. A sprocket 44 (Fig. l) is also secured to the shaft 34 and through the chain 46 is connected to a sprocket 48 secured to a shaft 5G on which the upper infeed roll 16 is also secured thereby furnishing power to the upper infeed roll at a predetermined rate of peripheral speed. The lower infeed roll 17 is driven at the same peripheral rate of speed (Fig. 2) but in the opposite direction to the upper roll 16 through a gear train consisting of the

gears

54, 56, 58 and 60.

The lower infeed roll 17 and the lower discharge roll 21 are shown in their inoperative position in Fig. l. The rolls 17 and 21 are mounted similarly. Each end of each roll is resiliently mounted on toggle arrangements indicated generally by the

reference characters

62, 64, respectively. Double acting cylinders or fluid motors 66, 63 acting between the frame 10 and the

toggle arrangements

62, 64 respectively are provided to move the rolls into and out of their operative positions shown in Fig. 2. The operation of the uid motors 66 is controlled by a manually operated valve ,'70 mounted at the front of the machine (Fig. 1) which is connected in standard manner. The operation of the fluid motors 68 is controlled by a solenoid operated valve 72 mounted on the frame 10,

the action of which will be described in greater detail shortly.

For further details of construction and operation reference is made to the above-mentioned Letters Patent No. 2,663,179.

For the purposes of the present invention a safety bar 76 is provided within the work treating zone 18 and immediately adjacent to the infeed roll 16 (Fig. 4). The bar 76 is secured by two curved arms 78 (only one of which is shown) to a shaft 80 which is pivotally mounted in lugs 82 projecting from the head casting 12. The bar 76 is yieldingly held above the normal path of movement of workpieces by a spring 84 whose action is limited by an arm 86 also secured to the shaft 80 and acting against a projection 88 on the head 12. Mounted on the head casting 12 is a safety switch SS which is arranged to be activated by a projection 90 extending from the right-hand curved arm 80 when the safety bar 76 is raised. Thus, when a workpiece W2 fails properly to pass through the work treating zone 18 the safety bar 76 is raised (as shown in Fig. 4) as the .workpiece W2 continues to be fed into the work treating zone 18 by the infeed rolls 16, 17 thereby closing the safety switch SS and activating the electrical and fluid circuits which will now be eX- plained.

Fig. 5 diagrammatically represents the electrical control system for the machine and a portion of the fluid control system for the machine. Three-phase current is drawn from the three lines ML and a transformer T is utilized to provide suitable current for the operation of tive magnetic coils A, B, C, D and E. The coil A is arranged to operate a relay K1 for controlling the motor CM which drives the work compacting tools, the operation of which is more fully described in the abovementioned Letters Patent No. 2,663,179. The coil B is adapted to close a relay K2 and the coil C is adapted to close a relay K3. The coil D operates a pneumatic time delay relay K4 and the coil E operates the solenoid uid valve 72. The secondary line from the transformer T is controlled by a stop button or switch SB the operation of which terminates all current flow. The tool motor CM is started by closing a switch TS and energizing the coil A. The contacts a serve to hold the relay K1 closed after the switch TS is released and opened and the motor CM therefore continues running. The motor RM for driving the feed rolls 16, 17 and discharge rolls 20, 21 is started in a feeding direction by closing a switch RS to energize the coil E thereby closing the relay K2. The motor RM continues running after thc switch RS is released or opened and other circuits energized by closing the switch RS remain energized due to the holding circuit flowing through the contacts b on the relay K2. When the switch RS is closed, the coil D of the time delay relay K4 is also activated opening contact m and closing contact n. Likewise coil E is energized thereby activating fluid valve FV introducing uid pressure through the pipes 92, 94 (Fig. 5 only) to the iluid motors 68 to raise the lower discharge roll 20 to its operative position. Thus by turning the valve 70 to raise the infeed roll 17 and by depressing the switches RS and TS the machine is placed in its operating condition. The switches RS, TS, SB, and IS (to be described later), which are shown only in Fig. 5 may be mounted in any convenient location adjacent to the front of the machine.

When the safety bar 76 is raised in the manner prcviously described and the safety switch SS is opened, the coils B, D and E are immediately deenergized. Current to the motor is cut off when the coil B is deenergizcd and the relay K2 opens. Reversed current is then applied to the motor RM through the relay ifl3 in the following manner to bring the motor RM and the

rolls

16, 17, 2%) and 21 to a rapid stop. Current flows through :l normally closed switch JS through the contacts m of the relay K4 when it is deenergize-:i and also through the contacts n of the relay K4 for a predcterminable period of time as the contacts n remain closed due to the action of the dash-pot DP thereby completing the circuit through the coil C to close the contacts of the relay K3. Preferably the dash-pot DP is adjusted so that the contacts n will open and deenergize the coil C and thc relay K3 immediately before the motor RM reverses its direction of rotation due to the reverse current applied. i-iow ever, the dash-pot DP can be so adjusted to permit the relay K3 to be energized for a longer length of time allowing the motor RM to reverse its direction of rotation thereby reversing the direction oi rotation of the infeed rolls 16, 17 and discharge rolls 20, 21 so that a fouled workpiece such as W2 will automatically be fed from the work treating zone. Preferably, however, the switch IS is utilized or depressed to complete a circuit through the coil C after the rolls have come to a rest in order to apply reversed current to the motor RM and thereby operate the infeed rolls 16, 17 in a reverse direction to extricate a fouled workpiece from the rnachine. The coil E is also deenergized when the safety switch SS opens thereby allowing the fluid valve FV to assume a position wherein fluid pressure ows through the pipes 96, 98 (shown only in Fig. 5) to the iluid motors 68 causing the lower discharge roll 21 to be lowered through the toggle arrangement 64 to the position shown in Fig. 4.

Thus in the operation of the machine, when a workpiece becomes fouled or jammed in the work treating zone, the safety bar 76 is raised as shown in Fig. 4. The feed rolls 16, 17 and discharge rolls 20, 21 immediately come to a halt and at the same time the lower discharge roll 21 is lowered to the position shown. Thus when reversed current is applied to the motor RM either automatically or by use of the switch JS to reverse the direction of rotation of the feed rolls 16, 17 to extricate the fouled workpiece W2, a prior fed workpiece W1 will not be fed back into the work treating zone since the lower discharge roll is in its inoperative position even though the discharge rolls are rotating in a reverse direction.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. A work piece treating machine having a pair of feed rolls, a pair of discharge rolls, work treating elements therebetween and common means for driving said pairs of rolls, a safety bar adjacent said work treating elements which is movable in response to pressure against it of a fouled workpiece, automatic means actuated by said movement for bringing the rolls quickly to a stop, automatic means likewise actuated for reversing the rotation of the feed and discharge rolls and automatic means also actuated by said movement for moving one of said discharge rolls out of its operative position thereby preventing a previously fed workpiece from being reintroduced to the work treating elements as a subsequently fed workpiece is being extricated by reverse rotation of the feed rolls.

2. A work piece treating machine having a pair of feed rolls, a pair of discharge rolls, work treating elements therebetween and common means for driving said pairs of rolls, the combination of a safety bar adjacent said work treating elements which is movable in response to pressure against it of a fouled workpiece, automatic means actuated by said movement for bringing the rolls quickly to a stop, means for reversing the rotation of the feed and discharge rolls and automatic means also actuated by said movement for moving one of said discharge rolls out of its operative position thereby preventing a previously fed workpiece from being reintroduced to the work treating elements as a subsequently fed workpiece is being extricated by reverse rotation of the feed rolls.

3. A work piece treating machine having a pair of feed rolls, a pair of discharge rolls, work treating elements therebetween and common means for driving said pairs of rolls, the combination of means for moving one of said discharge rolls into and out of operative relation, a safety bar adjacent said work treating elements which is movable in response to pressure against it of a fouled workpiece, an electrical circuit which is `activated by movement of the safety bar, said circuit comprising means for quickly stopping the operation of the rolls, means for reversing the direction of rotation of the feed and discharge rolls, and means within said circuit for activating the discharge roll moving means to bring one of said discharge rolls out of its operative position thereby preventing a previously fed workpiece from being reintroduced to the work treating elements as a subsequently fed workpiece is being extricated by reverse rotation of the feed rolls.

4. A work piece treating machine having a pair of feed rolls, a pair of discharge rolls, work treating elements therebetween and a single electric motor for driving both pairs of rolls, the combination of fluid means for moving one of said discharge rolls into and out of operative relation, a safety bar between the work treating elements and the feed rolls which is movable in response to pressure against it of a fouled workpiece, an electrical circuit. which is activated by movement of the safety bar, said circuit comprising electrical means for reversing the current to the driving motor for said rolls for a predeterminable period to bring ,said rolls to a quick stop, means for applying further reverse current to said driving motor to rotate said feed and discharge rolls in an opposite direction, and means within said circuit for activating said discharge roll moving means to lower said discharge roll out of its operative position thereby preventing a previously fed workpiece from being reintroduced to the work treating elements as a subsequently fed workpiece is being extricated by reverse rotation of the feed rolls.

5. A work piece treating machine having a pair of feed rolls, a pair of discharge rolls, work treating elements therebetween and a single electric motor for driving both pairs of rolls, the combination of fluid means for moving one of said discharge rolls into and out of operative relation, a safety bar mounted between the work treating elements and the feed rolls which is movable in response to pressure against it of a fouled workpiece, an electrical circuit which is activated by movement of the safety bar, said circuit comprising electrical means for reversing the current to the driving motor for said rolls for a predeterminable period to bring said rolls to a quick stop, means for applying further reverse current to said driving motor to rotate said rolls in an opposite direction, and means within said circuit comprising a relay coil for operating a fluid valve for activating said discharge roll moving means to lower said discharge roll out of its operative position thereby preventing a previously fed workpiece from being reintroduced to the work treating elements as a subsequently fed workpiece is being extricated by reverse rotation of the feed rolls.

References Cited in the file of this patent UNITED STATES PATENTS 584,073 Dexter June 8, 1897 1,917,359 Cameron July 11, 1933 2,547,470 Janke Apr. 3, 1951