US1916845A

US1916845A - Automatic feed controlling mechanism for punch presses and the like

Info

Publication number: US1916845A
Application number: US575324A
Authority: US
Inventors: George H Leland
Original assignee: Leland Electric Co
Current assignee: Leland Electric Co
Priority date: 1931-11-16
Filing date: 1931-11-16
Publication date: 1933-07-04
Anticipated expiration: 1950-07-04

Description

, G. H. LELAND July 4, 1933.

AUTOMATIC FEED CONTROLLING MECHANISM FOR PUNCH PRESSES AND THE LIKE Filed Nov. 16. 1931 3 Sheets-Sheet 1 /NV/VT7R b GEORGE H. LELAND.

his A TTOPNEY July 4, 1933. G H LELAND 1,916,845

AUTOMATIC FEED CONTROLLING MECHANISM FOR PUNCH PRESSES AND THE LIKE /1/Is ATTORNEY July 4, 1933.

G. H. LELAND AUTOMATIC FEED CONTROLLING MECHANISM FOR PUNCH PRESSES AND THE LIKE Filed Nov. 16

1931 5 Sheets-Sheet 3 INVENTUR y GEORGE H. LELAND.

L/IVE h/s A TTORNEY Patented July 4, 1933 UNITED STATES PATENT OFFICE GEORGE E. LELAND, OF DAYTON, OHIO, ASSIGNOR TO THE LELAND ELECTRIC COMPANY, OF DAYTON, OHIO, A CORPORATION OF OHIO AUTOMATIC FEED CONTROLLING MECHANISM FOR PUNCH PRESSES AND THE LIKE Application filed November 16, 1931.

This invention relates to an automatically controlled feeding mechanism for punch presses and the li e.

One object of the invention is to. provide means whereby the strips introduced into the press will automatically control the feeding mechanism to cause the strip to be properly positioned with relation to the dies or other operating part of the machine.

In punch presses of the type to which the invention is applied the strips are fed through the press by feeding rollers, one of which is movable toward and from the other. This movable roller is moved to its inoperative position upon each downward stroke of the movable die member so that the strip will be released to permit it to be alined prior to its engagement by the die. Manually operated means are provided for retaining the movable roller in its inoperative position during the insertion of a strip between the rollers. The manual control of the retaining device is not only slow in operation but it is otherwise unsatisfactory. For example, should the operator fail to properly position the retaining device prior to inserting a strip between the rollers or should the retaining device be prematurely actuated to release the movable roller the strip will be jerked through the operators hands, by the feed rollers, which frequently results in injury. Further, it is difficult with such an arrangement to accurately position the strip with relation to the dies.

A further object of the invention is to provide means controlled by the strip itself for controlling the position of the roller retaining device.

To this end it is also an object of the invention to provide means actuated by the insertion of the strip between the feeding rollers to cause the retaining device to be retreated and other means controlled by the strip as it is advanced by the feeding rollers 45 to rause the retaining device to be held in its retracted position until the strip has been advanced the desired distance.

A further object of the invention is to provide means for automatically interrupting the operation of the press in the event that Serial No. 575,324.

two super-imposed strips are presented to the feeding mechanism.

Other objects of the invention will appear as the mechanism is described in detail.

In the accompanying drawings Fig. 1 is a side elevation of a press equipped with my invention; Fig. 2 is a plan view of the feed table; Fig. 3 is a detail view, partly in section, of the electrically operated device for controlling the roller retaining device and the switch actuating mechanism for causing the initial operation thereof; Fig. 4 is a detail view of a strip controlled switch operating device for causing the retaining device to be held in its retracted position; Fig. 5 is a section taken on the line 55 of Fig. 4; Fig. 6 is a section taken on the line 6-6 of Fig. 3, showing the switch actuating mechanism in elevation; Fig. 7 is a section taken on the line 77 of Fig. 3; Fig. 8 is a detail view of one of the strip inserting rollers; Fi 9 is a sectional detail view of a retarde switch actuating device forming part of the mechanism for automatically stopping the press; Fig. 10 is a plan view of t e device shown in Fig. 9; Fig. 11 is a diagram of the circuits for the controlling devices; and Fig. 12 is a detail view of the clutch.

In these drawings I have illustrated one embodiment of m invention and have shown the same as app ied to a punch press of a well known type. It will be understood, however, that this particular embodiment has been chosen for the purposes of illustration and that the controlling mechanism may take various forms and may be applied to punch presses or other machines of various kinds. The controlling mechanism here illustrated is designed primarily for use in combination with the strip delivery mechanism shown and described in my co-pending a plication filed November 9, 1931, Serial 0. 573,785, but it will be apparent that it may be used with strip delivering mechanism of various kinds or with a hand fed ress.

The press to which the invention is ere applied comprises a main frame or supporting structure 10 on which is mounted a movable operating member or ram 11 which carries the 1 movable die member or punch 12. As here shown, the die is of the progressive type and comprises two parts to operate successively on t e same portion of the strip. The press is provided with a feeding-in device 13 and a feeding-out device 14 arranged at the opposite ends thereof, these feeding devices comprising supel'imposed rollers. The lower roller of each feeding device is carried by a shaft 15 having secured thereto a pinion 16 which meshes with the adjacent end portion of a reciprocatory toothed bar 17, the pinions being connected with the respective shafts by overrunning clutches in a well known manner, not here shown, so that the feeding rollers will be actuated by the movable reciprocatory member in one direction only. Reciprocatory movement is imparted to the bar 17 by a rock arm 18 mounted on the main frame of the machine and havin a slot 19 through which extends a stud or rol er 20 eccentrically mounted by a cam 21. This cam is connected with the driving mechanism for the press by the usual spring retracted clutch, which is operated against the action of the spring to set the clutch by means of a foot lever 22. In the particular clutch mechanism here shown the 11 wheel 90, which is connected with a suita 1e source of power, is rotatably mounted on a shaft 91 and carries one member 92 of a jaw clutch, the other member 93 of which is splined to the shaft 91. The clutch member 93 has an extension 94 which is provided with longitudinal bores 95 to receive studs 96 carried by a supporting member 97 mounted on the s aft 91 and held a ainst axial movement, as by contact with a caring 98 for the shaft 91. Sprin 99 mounted in the bores 95 and actin on t e studs 96 tend to move the clutch mem or 93 into operative engagement with the clutch member 92 and serve to normally maintain a connection between the driving mechanism and the operative arts of the machine. The extension 94 o the clutch member 93 is provided with a eripheral cam 100 and a plunger 101 is sli ably mounted in a bearing 102 for movement into and out of the path of the cam 100. This plunger is connected by a link 103 to the foot lever 22 so that the plunger ma be moved to an inoperative position by t e depression of the lever 22. A s ring 104 acts on the plunger 101 to move t e same into its operative position when the foot lever 22 is released and thus cause the cam 100 to engage the plunger and retract the clutch member 93, thereby disconnecting the drivin mechanism from the operative arts of t e machine. The upper end of s own at 23, to receive a slide block 24 which is connected with the reciprocatory bar 17 and imparts movement thereto. In presses equi ped with progressive dies as here shown e second stage die is proe rock arm 18 is slotted, as

vided with alining devices, such as pilot pins adapted to extend through openings ormed in the strip by the first stage die, to properly aline that strip with the second stage die. In order that the strip may be free for movement by the alining devices it is released from the feeding devices by moving the up er feed rollers out of engagement therewit during the latter portion of the downward movement of the ram. As shown in Fig. 3 the upper feed roller 25 of the feeding-in device has its bearings mounted in supporting structures 26, one only of which is shown, and these supporting structures are pivotally mounted, as by rigidly securing them to a transverse shaft 27. The upper roller 28 of the feeding out device is similarly mounted. Rigidly secured to the shafts 27 are inwardly extending arms 29, as shown in Fig. 1, the inner ends of which are connected by links 30 with levers 31 which are ivotally mounted between their ends and aving their inner portions arranged in engagement with a plun or 32 which rests upon and is actuated gy the cam 21, the arrangement being such that during the downward movement of the ram the levers 31 will be actuated in a direction to draw the inner ends of the arms 29 downwardly and thus lift the upper feeding rollers and release the strip. When a second strip is to be fed into the press it is desirable that thc feeding-in rollers shall be maintained in their separated iositions until the strip has been inserted and properly located. For this pur ose a latch 33 is pivotally mounted on tie side of the press and provided with a shoulder to engage beneath a part of a roller supporting structure, such as an adjustable screw 34, and thus support that structure in its elevated position. The latch also is provided with a recess 35 to receive the end of the screw when the latch is retracted and permit the roller to move to its operative position. The press structure so far described is well known and forms no part of the present invention exce t in so far as it enters into combination wit the novel features which will be hereinafter described.

In presses of the kind here shown the clutch actuating foot lever 22 is usually retained in its lower or operative osition by a manually operated latch. In the present machine I have substituted for that latch a ma net 36, the armature 36a of which is carrie by the lever and when the magnet is energized will retain the lever in its lower position. This enables the operation of the press to be automatically interrupted throu h mechanism which will be later describe In order that the latch 33 and the movable feeding member, or upper feeding-in roller, may be automatically controlled I have provided strip controlled actuating mechanism for retracting the latch and for again moving it to its operative position. This actuating mechanism comprises a magnet 37 which is preferably in the form of a solenoid, the core 38 of which is slidably mounted on a rod 38a extending through the coil. Rigidly connected with the core 38 and, in the present instance, forming a part thereof, is a tubular rod 39, the outer end of which is slidably mounted on a reduced end portion 40 of a member 41 pivotally mounted on the latch. A spring 42 is coiled about the tubular rod 39 and is connected at one end with that rod adjacent to the core 38 and is connected at its other end with the pivoted member 41 beyond the end of the tubular rod 39. A second spring 43 is coiled about the core 38 within the coil of the solenoid and tends to move that core outwardly when the solenoid is deenergized. The energization of the coil will retract the core 38 and place the spring 42 under such tension that it will withdraw the latch 31 from its operative position with relation to the roller supporting structure, thus permitting that structure and roller to be moved downwardly. When the solenoid is deenergized the spring 43 will press the core 38 outwardly and cause the end of the tubular rod 39 to engage the pivoted member 41 and move the latch toward its operative position. Inthe operation of the press it is desirable that the upper feed roller should be retained in its inoperative position until the strip has been inserted and moved to such a position with relation to the dies that the normal operation of the feed rollers will correctly position the end portions thereof with relation to the dies as the strip is fed forward. I have therefore provided means arranged to be actuated by the strip, when it has been )roperly positioned, to energize the magnet and withdraw the latch when the roller is next lifted by its cam. This means comprises a switch, here shown as a mercury switch, 45, which is connected in circuit with the magnet 37. This switch is carried by a bracket 46 secured to a shaft 47 which is journaled in upright bars or standards 48 rigidly secured to a part 49 of the press frame, thus permitting the switch to be tilted from its open to its closed position. A spring 50 acts on the switch supporting bracket to old the switch normally in its open position.

Links

51 and 52 are pivotally connected with the standards 48 and extend forwardly some distance beyond the same. Pivotally mounted on the ends of these links is a vertically arranged member 53 on which is pivotally supported a lever 54, at 5 40 the upper end of which is connected by a link 55 with a rock arm 56 secured to the shaft 47 The lower end of the supporting member 53 is arranged above an opening 57 in the strip supporting table 58 of the press and when there is no strip in position on that table the lower end of the supporting member will extend into the opening 57 and the lower end of the lever 54 will be arranged in the path of a strip which is inserted in the press. When this strip engages the lever the latter will be actuated thereby to move the switch 45 to its closed position, thus energizing the magnet 37 and actuating the latch 33 to release the feed roller and its supporting structure and permit the same to be moved downward. As the roller moves downwardly a two part arm 59, which is rigidly connected with the sup porting structure for the roller, will engage studs 60 on the lever supporting member 53 and lift that member and the lever out of the path of the strip, this operation taking place very quickly so there is no appreciable interruption of the strip and no interference is offered to the movement of the strip by the feed rollers when the upper roller assumes its operative position with relation thereto. A spring 61 acts on the upper link 51 to press the studs 60 against the arms 59 and support the lower end of the lever supporting member 53 above the upper surface of the strip when the arms are in their elevated positions. Thus the lever and its supporting member rise and fall with the arms 59, and, when the upper feed roller is moved to its operative position, their downward movement is limited by contact of the supporting member with the strip and when the rear end of the strip has passed the supporting member the latter will move to its lowermost position and thereby position the lever in the path of a succeeding strip.

As soon as the switch actuating lever 54 is moved out of engagement with the end of the strip which has actuated the same the spring 50 will return the switch 45 to its open position, thus breaking the circuit through The magnet. In order to maintain the latch 33 in its inoperative position during the feeding of the strip through the press, and thus permit the movement of the roller to be controlled wholly by its actuating cam 21. I have connected :1 second switch 62 in circuit with the magnet 37 and in parallel with the switch 45 and this second switch is so controlled that it will prevent the complete deenergizing of the magnet 37 until the rear end of the strip has passed or is close to the feeding-in rollers. The second switch is then moved to its inoperative position and the magnet completely deenergized, thus causing the latch to be returned to its operative position and the feeding-in roller 25 held in its inoperative position. The continued movement of the strip is then effected wholly by the feeding-out rollers. This second switch 62, which is also in the form of a mercury tube, is supported by a bracket 63 secured to a shaft 64 jonrnaled in bearings 65 which, in the present instance, are secured to the underside of a feed table 66. Pivotally secured to the feed table 66, at one new a roller 69, which normally extends through an opening 74 in the table. The bracket also comprises a second part 70 which extends beneath the table and which carries a plate 71, preferably of insulating material. The part 70 of the bracket is bifurcated and an arm 72 is ivotally mounted between its ends upon tliis bifurcated portion of the bracket. A roller 73 is mounted on the outer end of the arm 72 directly beneath the upper roller (39. The inner end of the arm 72 is yieldahly connected with the plate 71 which is also carried by the bracket. As here shown, a screw 75 is mounted in the arm 72 and extends loosely through an opening in the plate 71. and a spring 76, confined between the head of the screw and the plate. resists the movement of the arm 72 away from the. plate, thus causing the arm and the bracket to normally move together about the axis 660: of the bracket and so positioning the arm and the bracket with relation one to the other that the rollers will be spaced apart a distance suliicient to permit the passage of a strip of normal thickness. The arm 72 is connected with the part 70 of the bracket by a pivot pin 77 which extends b yond one side of the part Ti) and is embraced by the slotted end of a crank arm 78 secured to the shaft (it which carries the switch supporting bracket, the arrangement being such that when the parts are in their normal position, shown in dotted lines in Fig. 4, the swich will be open. The bracket 67 and arm 72 tend to move downwardly by gravity and this movement is limited by a stop 79 so arranged that the roller (59 will extend into the opening 74 in the table (56. 'lhcsc rollers are arranged adjacent to and slightly in advance o the feeding-in rollers so that a strip must pass between the rollers (39 and 73 before it is inserted between the feeding-in rollers. The

rollers

69 and 73 are spaced apart a distance approximately equal to the thickness of the strlp to be operated on and p when such a strip is inserted between these rollers the structure as a whole will be moved u )wardly about the axis of the bracket, thus ti ting the switch (52 to its closed position. Inasmuch as the magnet should not operate the latch until the forward end of the strip '3 has been moved some distance beyond the feeding-in rollers I have inserted in the circuit of the switch 62 a resistance 80 which will so reduce the strength of the current that the magnet will not be suificiently energized to move its armature against the action of the springs 42 and 43. Consequently the magnet will not be fully energized until the forward and of the strip is advanced beyond the feedin -in rollers and has engaged the lever 54 an actuated the switch 45. This full energization of the me at, which causes the latch to be retracte is of short duration, as the switch 45 returns at once to its open position. However, the energization of the magnet through the switch 62 and resistance 80 is sufficient to retain the armature in its retracted position against the action of the springs after it has been once retracted and therefore the latch will not be returned to its operative position until the rear end of the stri has passed the controlling

roll crs

69 and 73 and the switch 62 has been again restored to its en position.

It will be ap are-nt t at in the operation of the press the ceding roller will be held in its inoperative position by the latch 81 so long as there is no strip between the controlling

rollers

69 and 73. When the strip is inserted between the controllin rollers the magnet 37 is only partially energized and does not withdraw the latch and the up or feeding roller remains inoperative until tl ie strip ongages the lever 54 and causes the switch to be closed, thus fully energizing the ma et and releasing the feeding roller. As the eeding roller moves to its operative position the lever supporting member 53 is lifted by the arms 59 and moved out of the path of the strip. The stri is then advanced intermittently by the ceding rollers as above described, the upper roller being moved to its inoperative position during each downward movement of the ram. The arms 59 move with the upper feedin roller and cause the lever supporting member 53 to rise and fall as that roller moves downwardly and upwardly. When the rear end of the strip has passed the controlling

rollers

69 and 73 the magnet 37 will be deenergized and the latch will move to its operative position and lock the upper feeding roller in its inoperative position. The feeding of the stri is then completed by the feeding-out r0 lers and when the rear end of the strip has passed the lever supporting member that member will move the lever into the path of the Succeeding strip and the cycle of operations will be reeated.

The controlling

rollers

69 and 73 also control a second switch which in turn controls the operation of the press as a whole. This second switch comprises a fixed contact member 81, carried by the plate 71, and a movable contact member 82 carried by the adjacent end of the pivoted arm 72. These contact members are connected in the circuit of the magnet 36 which retains the clutch operating lever 22 in its operative position. So long as the rollers are in their normal positions the

contacts

81 and 82 will be in engagement and the circuit for the switch controlling magnet will be closed. Inasmuch as the plate 71 is carried by the bracket 67 and moves with the arm 72 in the normal operation of the device the switch will not be opened by the passage of a single normal strip but if a strip of excessive thickness or two superim osed strips be presented to the rollers 69 an 73 the rollers will be forced apart and the arm 72 moved with relation to the plate 71, thus separating the

contacts

81 and 82 and deenergizing magnet 36 and permitting the lever 22 to be moved to its inoperative position by the action of the clutch springs.

The action of the controlling device just described will instantly stop the press in the event two superimposed strips, or a strip of abnormal thickness, are interposed between the rollers 79 and 73. However, only a slight amount of relative movement need be imparted to the bracket 67 and the arm 72 in order to open the circuit and stop the press and it may sometimes happen that a small protrusion or a lump on the surface of the strip passing between the rollers will open the circuit and stop the press when there is no necessity therefor. To avoid this unnecessary stopping of the press I have provided means whereby'the deenergization of the magnet 36 will be so retarded that a lump or other short projection on the strip will pass the rollers and permit the

contacts

81 and 82 to be again closed before the magnet has been deenergized and the press stopped. For this purpose I have connected a switch 83 in circuit with the magnet 36 and in parallel with the switch 8182 and have rovided means controlledby the opening 0 the circuit 8182 for causing the switch 83 to be opened after a predetermined interval of time. The two switches being in parallel it will be obvious that the magnet cannot be deenergized until both switches are opened and therefore if the circuit is closed at 8182 before the switch 83 opens the magnet will not be deenergized. As here shown, the switch 83 is in the form of a mercury tube carried by a bracket 84 which is pivotally mounted on a supporting member 85. Mounted on this supporting member is a magnet 86, here shown as a solenoid c011, and a cylinder 87 supported by the member 85 extends through the coil to a point below the same and has its lower portion closed. The armature or core for the magnet is shown as a plunger 88 slidably mounted within the cylinder 87 and operatively connected with the switch supporting bracket 84. As here shown, an arm 89 is rigidly connected with the bracket 84 and is connected with the plunger 88 by a coiled spring 90. The plunger or armature 88 fits snugly within the cylinder with only a slight clearance about the same. The magnet coil 86 is connected at its respective ends with the

terminals

81 and 82 of the main switch. When the plunger 88 is at its lowermost position the switch 83 will be held in its closed position. Because of the relatively high resistance in the magnet coil 86 the current will flow normal y through the

closed contacts

81 and 82 and through the magnet 36 but if the

contacts

81 and 82 are separated and the circuit there broken the current will then flow through the magnet 86, thus energizing that magnet and exerting an upward pull on the plunger or armature which will tend to move the switch 83 to its open position. However the plunger can only move upwardly as fast as the fluid can escape about the same into the lower end of the cylinder and therefore its movement is retarded for a brief interval, sufiicient to permit the strip to move forward a short distance. If during this movement the lump or other projection on the surface of the strip passes beyond the

rollers

69 and 73 the

contacts

81 and 82 will again close and the magnet 86 will be either completely deenergized or deenergized to such an extent that it will not actuate its armature. However, if the

contacts

81 and 82 are maintained separated for any appreciable length of time, as when superimposed strips are inserted between the

rollers

69 and 73, the switch 83 will be opened and the magnet 36 deenergized.

The feeding table 66 which is arranged in advance of and leads to the feeding-in rollers is preferably provided with power operated mechanism for inserting the strip between the feeding-in rollers when the upper roller is in its ino erative position. As here shown, the inserting mechanism comprises a. pair of cone-shaped

rollers

91 and 92 extending through and above the table and having connected therewith pulleys 93 which are connected by belts 94 with an electric motor 95. The rollers 92 are spaced apart a distance sufficient to receive the strips between them and one of the rollers is yieldable so as to cause the two rollers to grip the strip with a feeding action. As here shown, the coneshaped rollers extend through slots 96 in the table and are carried by arms 97 pivotally mounted beneath the table. The arm of the roller 91 is acted upon by a spring 98 which tends to move it toward the roller 92.

Thus it will be apparent that when the strip is deposited'upon the table 66 it will be engaged by the inserting

rollers

91 and 92, moved between the controlling

rollers

69 and 73 and then advanced between the feeding-in rollers, the upper feeding-in roller being held in its inoperative position by the latch. When the forward end of the strip reaches a predetermined position the latch actuating magnet will be energized, the latch moved to an inoperative position and the strip will be gripped by the rollers and fed to the dies. So long as the strip is between the

rollers

69 and 73 the magnet 37 will be energized sufiiciently to hold the latch in its retracted position but as soon as the rear end of the stri passes the

rollers

69 and 73 the magnet 3 will be completely deenergized and the latch returned to its operative position where it will engage the roller sup orting structure when this structure is again elevated, thus again holding the roller in its inoperative position.

While I have shown and described one embodiment of my invention I wish it to be understood that I do not desire to be limited to the details thereof as various modifications may occur to a person skilled in the art.

Having now fully described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. The combination with a machine having a part to operate on strips of material fed successively thereto, cooperating members to feed a strip to said operating part, one of said members being movable to an inoperative position, and a device to retain said memher in its inoperative position, of means for moving said retaining device to an inoperative position, comprising a part arranged in a predetermined position beyond said feeding members, in advance of the part which operates on the strip and in the path of a strip inserted between said feeding members, and means for moving the last mentioned part out, of the path of said strip after it has been actuated thereby, and before said strip has been advanced by said feeding members.

2. The combination with a machine having a part to operate on strips of material fed successively thereto, cooperating members to feed a strip to said operating part, one of said members being movable to an inoperative position. and a device to retain said member in its inoperative position, of an actuating device to move said retaining device to an inoperative position and release said member for movement to its operative position, means arranged between said feedmg members and said operating part and in the path of a. strip inserted between the feeding members to cause the operation of said actuating device, and means controlled by the movement of said member to its operative position to move the last mentioned means out of the path of said strip.

3. The combination with a machine having a part to operate on strips of material for controlling the operation of said actuat ing device comprising a part arranged beyond said feeding members and in the path of a strip advanced by said power operated mechanism.

4. The combination with a machine having a part to operate on strips of material fed successively thereto, cooperating membcrs to feed astrip to said operating part, one of said members being movable to an inoperative position, and a device to retain said member in its ino erative position, of an electrically controlle device to move said retaining-device to an ino rative position, a switch in circuit with said electrically controlled device, and a switch actuating device havin a part arranged in advance of said operating part and in the path of a stri which has been inserted between said feed ing members.

5. In a machine of the character described, having a pair of feed rollers one of which is movable toward and from the other, a retaining device to hold the movable roller in spaced relation to the other roller, driving mechanism for said rollers, and a device to control the operative connection between 'said driving mechanism and said rollers, a ma net to hold said controlling device normal y in an operative position, a switch in circuit with said magnet, means including a magnet to move said roller retaining device to its inoperative position, means controlled by a strip inserted between said rollers to initially energize the last mentioned magnet, a switch connected in circuit with said last mentioned magnet to maintain the same energized independentl of the first mentioned energizing means, a racket )ivotally mounted in advance of said fee in rollers, an arm pivotally mounted on sair bracket, yieldable means to hold said bracket and said arm normall against relative movement, rollers carried by said bracket and said arm and spaced :1 art a distance substantially equal to the t ickness of said strip and arranged to receive said stri between them, said rollers being supporter normally in such a position that they will be moved in unison when a strip is inserted between them and will be separated to move said bracket and said arm with relation one to the other when two su erimposed strips are inserted simultaneous y between the same, means actuated by the movement of said bracket and said arm in unison to close the last mentioned switch, and means actuated by the relative movement of said bracket and said arm to open the first mentioned switch.

6. In a strip feeding mechanism comprising a feeding table having an opening therein, a plurality of electrically controlled devices and separate switches in circuit with the respective electrically controlled devices, a switch actuating device comprising a bracket pivotally mounted at one edge of said tabio and having a part overhanging said table, a roller carried by said part of said bracket and arranged in line with the opening in said table, said bracket having a sec- 0nd part extending beneath said table, an arm pivotally mounted between its ends on said second part of said bracket, a roller mounted at one.end of said arm and arranged beneath the opening in said table, yieldable means for holding said arm normally against 'movement with relation to said bracket, means for normally supporting said bracket and said arm in such positions that the first mentioned roller will extend into said opening and will be elevated by a strip inserted between said rollers, thus causing the bracket and the arm to move in unison, means for operatively connecting said bracket and said arm to one of said switches to cause the same to be actuated when said arm and said bracket move in unison, and means for connecting a second switch with that end of said arm opposite its roller to cause said second switch to be actuated by said arm when said arm is moved with relation to said bracket.

7. In combination with a machine having feeding members one of which is movable toward and from the other, and a device to retain said movable member in spaced relation to the other member, a feeding table over which a stripof material may be moved between said feeding members while the latter are in their separated positions, means controlled by said strip to retract said retaining device and cause said movable member to operatively engage said strip when the forward end of said strip has been moved to a predetermined position with relation to said machine, and means controlled by said strip to hold'said retaining device in its inoperative position until the rear end of said strip has been moved to a position adjacent to said feeding members and to then cause the same to be moved to its operative position.

8. In a punch press having rollers for feeding a strip of material to said press, means for movin one of said rollers to an inoperative position upon each operative stroke of said press, and a device to retain said movable roller in its inoperative position, a feed table leading to said rollers, power operated mechanism for moving a strip over said table and inserting thesame between said rollers while said movable roller is in its inoperative position, means actuated by said strip as it is advanced by said power operated mechanism to cause said movab e roller to be released by said retaining device and to operatively engage said strip, and other means controlled by said strip as it is advanced by said feeding rollers to hold said retaining device in an inoperative position until the rear end of said strip is in a position adjacent to said feed rollers.

9. In a machine of the character described, having a pair of feed rollers one of which is ing device to hold the movable relief in spaced relation to the other roller, driving mechanism for said rollers, and a device to control the operative connection between said driving mechanism and said rollers, a magnet to hold said controlling device normally in an operative position, a switch in circuit with said magnet, means including a magnet to move said roller retaining device to its inoperative position, means controlled by a. strip inserted between said rollers to initially energize the last mentioned magnet, a switch connected in circuit with said last mentioned magnet to maintain the same energized independently of said energizing means, an actuating device for said switches comprising two members pivotally mounted in advance of said feeding rollers and adapted to receive between them a strip of material as the latter is moved toward said feed rollers, means to cause said members to move in unison when a strip of normal thickness is inserted between them and to move with relation one to the other when a strip of abnormal thickness is inserted between them, means controlled by the movement of said members in unison to close the last mentioned switch, and means controlled by the relative movement of said members to open the first mentioned switch.

10. In a strip feeding mechanism comprising cooperating feeding members, one of which is movable to aninoperative position, and means for retaining said member in its inoperative position; an electrically controlled device to move said retaining device to an inoperative position, a switch in circuit with said electrically controlled device, a switchactuating device having a part arranged beyond said feeding members and in the path" of a strip which has been inserted between'the same while the one member is in its inoperative position, and means for moving said part of said switch actuating device out of the ath of said strip after said retaining device has been moved to an inoperative position.

11. In a strip feeding mechanism comprising cooperating feeding members, one of which is movable to an inoperative position, and means for retaining said member in its inoperative position; an electrically controlled device to'move said retaining device to an inoperative position, a switch in circuit with said electrically controlled device, yieldable means to retain said switch normally in its open position, an actuating device for said switch having a part arranged to be actuated by a strip which has been inserted between said feeding members while the one member is in its inoperative position, to, move said switch to its closed position, and means for releasing said switch for movable toward and from the other, a retainmovement to its open position after said retaining device has been moved to its inoperative position.

12. In a strip feedin mechanism comprising cooperating feeding members, one of which is movable to an inoperative position, and means for retaining said member in its ino erative position; an electrically controlled device to move said retaining device to an inoperative position, a switch in circuit with said electrically controlled device, a su porting structure movably mounted beyonr said feeding members, a switch actuatlng device carried b said supporting structure and o erativel y connected with said switch, yiel able means acting on said porting structure to move said switch actuating device into the path of a strip winch has been inserted between said feeding members while the one member is in its inoperative position, and means for moving said supportin" structure against the action of said ieldab le means after said retaining device as been moved to an inoperative position.

13. In a strip feedin mechanism comprisin cooperating feeding members, one of which is movab e to an inoperative position, and means for retaining said member in its ino )erative position; an electrically controlled device to move said retaining device to an inoperative osition, a switch in circuit with said electrically controlled device, yieldable means to retain said switch normally in its open position, a supporting structure movably mounted beyond said feedin members, a switch actuating device carried y said supporting structure and o rativcly connected with said switch, yiel able means actin on said supportin structure to move sai structure and sai switch actuating device into the path of a strip which has been inserted between said feeding members while the one member is in its inoperative position and means controlled by the movement of said movable feeding member toward the other feeding member to move said supporting structure and said switch actuating device out of the nth of said strip and to release said switc for movement to its open position.

14. In a strip feeding mechanism comprising cooperatin feeding members, one of which is movalile to an inoperative position, and a device for retaining said member in its inoperative osition; an actuating device to move said retaining device to an inoperative position, means arranged beyond said feeding members and in the path of a strip which has been inserted between the same while the one member is in its inoperative position to cause the operation of said actuating device, means to move the last mentioned means out of the path of said strip after said retaining device has been actuated and before said strip is advanced by said feeding members, and other means to cause supsaid actuating device to hold said retaining device in its inoperative position.

15. In a strip feeding mechanism comprising cooperating feedin' members, one of which is movable to an lnopcrative position, and means for retaining said member in its inoperative position; an electrically controlled device to move said retaining device to an inoperative position, a switch in circuit with said electrically controlled device, a switch actuating device having a part arranged beyond sald feeding members and in the path of a strip which has been inserted between the same while the one member is in its inoperative msition, means for moving said switch to its open position after said retaining device has been moved to its inoperative position, a second switch connected in circuit with said electrically controlled device in parallel with the first mentioned switch, and means controlled by said strip for retaining said second switch in its closed position after the first mentioned switch has been 0 ened.

16. n a strip feeding mechanism comprising cooperating feeding members, one of which is movable to an inoperative position, and means for retaining said member in its inoperative position; an electro-magnct having an armature, means for operatively connecting said armature with said retaining device, two switches connected in circuit with said magnet and in parallel one with the other, means arranged beyond said feeding members to be engaged by a strip inserted between the same and close one of said switches to cause said retaining device to be moved to its ino)erative position, means to 0 en said switc after said retaining device as been so actuated, and means arranged ad- 'acent to said feeding members and controlled y said strip to close the second switch and to maintain the same closed after the first mentioned switch has been opened.

17. In a strip feeding mechanism compris mg cooperatin feeding members, one of which is movab e to an inoperative position, and means for retaining said member in its inoperative position; an clcctro-magnet havmg an armature, means for operativcly connecting said armature with said retaining de vice, two switches connecting in circuit with said magnet and in parallel one with the other, means arranged beyond said feeding members to be engaged by a stri inserted between the same and close one 0? said switches to cause said retaining device to be moved to its moperative position, means to open said switch after said retaining device has been so actuated, means arranged adjacent to said feeding rollers and controlled by said strip to close the second switch and to maintain the same closed after the first mentioned switch has been opened, and means for so controlling the current delivered to said magnet through said second switch that said magnet will not be energized thereby sufiiciently to cause said retaining device to be withdrawn from its operative position but will retain the same in its inoperative position after it has been withdrawn.

18. In a strip feeding mechanism comprising cooperatin feeding members, one of which is movab e to an inoperative position, and means for retaining said member in its ino rative position; a rod connected with sai retaining device and having a shoulder spaced from the outer end thereof, a magnet having an armature, a tubular rod slidably mounted on the first mentioned rod and connected with said armature, a spring actin on said armature to cause said tubular r to en ge said shoulder and move said retaining evice to its operative position, a second spring connected at one end with the first mentioned rod and at its other end with said armature, whereby when said magnet is energized said armature will place the second spring under tension and cause it to move said retaining device to an inoperative position, a switch connected in circuit with said magnet to fully energize the same a second switch connected in circuit with said magnet to artially energize the same, means control ed by a strip inserted between said feeding members to close the first mentioned switch when the forward end of said strip has been moved to a predetermined position beyond said feedin members, means to open said first mentionef switch after the movable member has been released, and means arranged adjacent to said feeding members to close the second switch when a strip is inserted between said feed rollers and to maintain the same closed until the rear end of the strip has passed the last mentioned means.

19. In a strip feeding mechanism comprising cooperating feeding members, one of which is movable to an ino rative position, and means for retaining said member in its inoperative position; an electro-magnet having an armature, means for operatively connecting said armature with said retaining device, two switches connected in circuit with said magnet and in arallel one with the other, means arrange beyond said feeding rollers to be engaged by a strip inserted betweenthe same and close one of said switches to cause said retaining device to be moved to its ino rative position, means to o 11 said switch after said retaining device as been so actuated, and a movable arm mounted in advance of and adjacent to said feeding members operatively connected with the second switch and having a art arranged to be engaged by a strip delivered to said feeding members and to actuate said arm to move said second switch to its closed position and to retain the same closed until said strip has moved past said part of said arm.

20. In a strip feeding mechanism comprising cooperating feeding members, one of which is movable to an inoperative position, and means for retaining said member in its inoperative position; drivin mechanism, means for operatively connecting said driving mechanism with said feeding members, means to interrupt said connection between said driving mechanism and said feeding members, a single controlling device arranged in advance of said feeding members to be engaged by a strip as the latter is moved toward said feeding members, said controllin device comprising a movable part arranged to be moved a predetermined distance by a strip of normal thickness and to be moved a further distance by a strip of excessive thickness, and means actuated by the first mentioned movement of said movable part to actuate said retaining device, and means actuated by the further movement of said movable part to cause the connection between said driving mechanism and said feeding members to be interrupted.

21. In a strip feeding mechanism comprising cooperating feeding members, one of which is movable to an inoperative position; driving mechanism for said feeding members, an electrically operated device to retain said movable member in its inoperative position, a switch in circuit with said electrically operated device, a second electrically operated device to control the connection between said driving mechanism and said feeding members, a switch in circuit with said second electrically operated device, a switch actuating device mounted in advance of said feeding members and comprising a movable gart arranged to be moved a predetermined istance by a strip of normal thickness, and to be moved a further distance by a strip of excessive thickness, and means controlled by the first mentioned movement of said movable part to actuate the first mentioned switch, and means controlled by the last mentioned movement of said movable part to actuate the last mentioned switch.

22. In a strip feeding mechanism comprising cooperating feeding members, one of which is movable to an inoperative position; driving mechanism for said feeding members, an electrically operated device to retain said movable member in its inoperative position, a switch in circuit with said electrically operated device, a second electrically operated device to control the connection between said driving mechanism and said feeding members, a switch in circuit with said second electrically operated device, a switch actuating device mounted in advance of said feeding members and comprising two movable members normally spaced apart a distance suflicient to permit the passage of a strip of normal thickness only, one of said members of said actuating device being or ranged to be actuated by a strip inserted between the two members, means to cause said members of said actuating device to move in unison when a stri of normal thickness is inserted between tiiem and to move with relation one to the other when a strip of excessive thickness is inserted between them, means controlled by the movement of said members in unison to actuate the first mentioned switch, and means controlled by the relative movement of said members to actuate the last mentioned switch.

23. The combination with a machine having a part to operate on strips of material fe successively thereto, mechanism to feed a strip of material to said operatin part, and means to render said feeding mec anism inoperative, of means located between and spaced from said feeding mechanism and said operating device and controlled by a stri inserted in said feeding mechanism whi e the latter is inoperative to render said feeding mechanism operative and cause it to act on said strip when the forward end of the latter is spaced a predetermined distance from said operating part.

24. The combination with a machine having a part to operate on strips of material fe successively thereto, cooperating members to feed a stripto said operating part,

and means to move one of said members to an inoperative position, of means located be- {ond said feeding members and controlled y a strip inserted between said members to cause the movement of said inoperative memher to its 0 ierative osition when the forward end 0 said strip has been moved to a predetermined position with relation to said operating part.

25. The combination with a machine having a part to operate on strips of material fed successively thereto, cooperating members to feed a strip to said operatin part, and means to move one of said mem ers to an inoperative position and a device to retain said member in said inoperative position, of means to cause said retaining device to release said member for movement to its operative osition when the forward end of said strip is in a predetermined position with relation to said operating part, said lastmentioned means comprising a part located in a predetermined position be ond said feeding members and in advance 0 said operating part and arranged to be actuated by a strip inserted between said feedin members.

In testimony whereof, I a it my signature hereto.

GEORGE H. LELAND.

CERTIFICATE OF CORRECTION.

Patent No. 1,916, 845.

July 4, i933.

GEORGE H. LELAND.

it is hereby certified that the to "The Leland Electric Company,

been issued Company, of Dayton, Ohio, a corporation of Ohio", terest only as shown by the records of assignments in above numbered patent was erroneously issued of Dayton, Ohio, a corporation of Ohio", as

whereas said patent should have and "The Leland Electric as assignee of one-half inthis office; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 29th day of August,

(Seal) M. J. Moore.

Acting Commissioner of Patents.

ranged to be actuated by a strip inserted between the two members, means to cause said members of said actuating device to move in unison when a stri of normal thickness is inserted between tiiem and to move with relation one to the other when a strip of excessive thickness is inserted between them, means controlled by the movement of said members in unison to actuate the first mentioned switch, and means controlled by the relative movement of said members to actuate the last mentioned switch.

In testimony whereof, I a it my signature hereto.

GEORGE H. LELAND.

CERTIFICATE OF CORRECTION.

Patent No. 1,916, 845.

July 4, i933.

GEORGE H. LELAND.

it is hereby certified that the to "The Leland Electric Company,

Signed and sealed this 29th day of August,

(Seal) M. J. Moore.

Acting Commissioner of Patents.