US1634382A

US1634382A - A cobpobation

Info

Publication number: US1634382A
Authority: US
Publication date: 1927-07-05
Anticipated expiration: 1944-07-05

Description

July 5, 1921.

F. H. OBERSCHMIDT CONTROLLER FOR POWER OPERATED MACHINES Filed Nov. 25. 1921 I INVENTOR. ("a-MM EMMWM ATTORNEY Patented July 5, 1927.

' UNITED STATES PATENT OFFICE.-

rnnnamcx 'r'r. onanscmrm'r, or cnnvnnann, onro', ASSIGNOR 'ro 'rmc' cumminme. 00., or umwauxna, WIBOONSIN,- A coaroaarron or wrsoonsm.

(DNTBOILEB I03 POWEB-OPEBA TED MACHINES.

- Application aled November 85, 1921. Serial No. 517,776.

This invention relates to controllers for and a co-operating platen 2 reciprocable by power operated machines and moreparticularl to safety controllers for machine tools. ertain types of machines are driven 8 through the medium of a clutch controlled by the operator and are sometimes provided with safety controllers including an electromagnetic latching device for lockmg the clutch in its'released position and a pair of manually controlled switches for controlling the energizing circuit of said device. Such switches are connected in series in the energizing circuit of said device and are located out of proximity to the movln parts of the machine whereby it is im ossi le for v the operator to start the mac me while either of his hands are in a dangerous position.

However, such safety controllers do revent the operator from removm hls ands from the control switches and eeping the machine in continuous operat1on, and the present invention has among its ob ects to provide a safety controller which is a aptnot " ed upon release of either control switch toefiect automatic sto ping of the machine after a given cycle 0 operation thereof.

Another object is to provide a safety controller of the character above stated including-an electro-magnetic clutch which is manually controlled to efiect startmg ofthe machine and is automatically controlled-to effect stopping of the machine after a given cycle of operation thereof.

Various objects and advantages of the mvention will hereinafter appear.

The accompanying drawing illustrates an embodiment of the invention which will now be described, it being understood that the embodiment illustrated is susceptible of modification and can also be applied to other types of machines than that illustrated m t e drawing.

In the drawing Figure 1 is-a schematic view'of a controller embodying the invention, the same bein shown in connection with a conventiona ty e of toggle press; Fig. 2 is a front elevational view of a mechanical embodiment of the toggle press with certain of the control parts in Fig. 1 mounted thereon.

Referring to Fig. 1 the toggle press Illustrated therein includes a stationary head 1 a cam 3 through the medium of a to lo 4. Cam 3 is fixed to a shaft 5 whichis1iven from a shaft 6 through the medium of a clutch 7. Shaft 6 has the usual cone pulley 8 fixed thereto for driving the same and 18 also provided with the usual fly wheel 9,

Field member 7" of clutch 7 is keyed to shaft 6 while the armature member=7 of said clutch is rotatably mounted on said shaft and has a pinion 10 fixed thereto. Pinion 10 meshes with a gear 11 fixed to a countershaft 12 and said countershaft has a pinion 13 fixed thereto which meshes with an internal gear 14 fixed to shaft 5. i

The controlmeans for the aforedescribed toggle press includes a snap switch 17, a palr of

push button switches

18 and 19 and a pair of double-

pole switches

20 and 21. As shown in Fig. 2

push button switches

18 and 19 are mounted in front of the press andupon opposite sides thereof and as hereinafter setforth the same when simultaneously depressed serve to establish an energizing clrcuit for clutch 7.

Switches

20 and 21 are provided with cam actuatin members 22 and 23 respectively and as ereinafter set forth, each of said switches is ada ted to establish a maintaining circuit for c utch 7 independently of

push buttons

18 and 19. Cams 22 and 23 are mounted for angular adustment upon a shaft 24 said shaft bei driven at a speed correspondingto the spe ofshaft 5 through the medium of a driving connection 25. i

The function and operation'of the aforedescribed controller together with the circuit connections, thereof will now be more fully described. Assuming that switch 17 is closed and that it is desired to start the press, push

buttons

18 and 19 are simultaneously de ressed to establish an energizing circuit or clutch 7. Such ener 'zlng circuit extends from line L through swltches 17 and 18 by

conductors

25 and 26 to and throu h the winding of clutch 7 by conductors 2 and 28 to and through switch 19 to line L. Upon engagement of clutch 7 cam 3 is driven in a clockwise direction and durin each revolution of said cam, platen 2 is raised and lowered and each of the cams 22 and 23 makes one complete revolution. Cam 22 isarranged so that during upward movement of platen 2 the same closes switch 20 while cam 23 is arranged to close switch 21 following closure of switch 20. Upon 010: sure of switch 21.cam 22 permits opening of switch 20 and upon completion of the cycle of operation of platen 2 cam 23 permlts opening of switch 21. Either of the

switches

20 and 21 when closed establishes an energizing circuit for clutch 7 extending from line L through the left hand pole of said switches by

conductors

30 and 26 to and through the winding of clutch 7 by conductors 27 and 31 through the right hand pole of said switches to line L. 'By enabling rotary angular adjustment of one or both of earns 22 and 23 with respect to shaft 2 1, in the manner aforeindicated, the duration of automatic control of the clutch energization within each cycle of operation of the device may be increased or decreased as desired.

From the foregoing it is apparent that after a given upward movement of platen 2 the operator is free to remove his hands from push buttons 18 and 1.9 to prepare the maternal for the next operation of the press. As soon as the press starts on its downward stroke the operator removes the finished part and inserts raw material for the next operation. If the operator finishes this work before the platen is in position to.

again begin the upward movement he simply holds

push buttons

18 and 19 depressed until switch 20 establishes-the maintaining circuit for clutch 7. Should the operator for some reason fail to complete the work u on completion of the downward stroke of p aten 2, switch 21 interrupts the maintaining circuit of clutch 7 to effect automatic stopping of the press.

What I claim is new and desire to secure by Letters Patent is:

1. In a safety device, the combination with a press having a reciprocating. member, an electromagnetic clutch for transmitting power thereto, right and left hand switches on said press biased to open position and adapted while simultaneously held closed to maintain an energizing circuit for said .clutch, a plurality of switches actuated by said press and adapted to close successively and open successively after closure of said first-mentioned switches to maintain an energizing circuit for said clutch throughout the remaining part of a cycle of operation of said press, and means for varying the time of closure of certain of said lastmentioned switches with respect to said cycle of operation.

2. In a safety device, the combination with a driven machine, of an electromagnetic clutch for transmitting power thereto, manually controlled switches adapted while closed simultaneously to establish and maintam an energizing circuit for said clutch, and adjustable means associated with said mamas machine for establishing a maintaining circuit for said clutch following initiation of the cycle of operation of said machine, said ineans'being adapted to interrupt said maintairiing circuit only upon completion of said 0 c e.

3. The combination with a machine of an electro-magnetic clutch for transmitting power thereto, safety control means for said clutch including a plurality of manually controlled switches adapted while closed simultaneously to establish and maintain an energizing circuit for said clutch, and a plurality of switches operated by said machine for establishing a maintaining circuit for said clutch during a given part of the cycle of operation of said machine, and means for varying the time of establishment of said maintaining circuit with respect to said cycle of operation.

4. The combination with a driven machine, of an electromagnetic. clutch for transmitting power thereto, safety control means for said machine including a plurality of manually controlled switches biased to open position and adapted while closed simultaneously toestablish and maintain anenergizin circuit for said clutch, means actuated by said machine for establishing an energizing circuit for said clutch independently of said switches, said means being adapted to establish said independent circuit following initiation of the cycle of operation of said machine and to interrupt the same upon completion of said cycle, and means for varying the time of establishment of said independent energizing circuit with respect to said cycle of operation.

5. The combination with a machine, of an electromagnetic clutch for transmitting power thereto and safety control means for said machine including a plurality of spaced manually operated switches biased to open position adapted while held closed to maintain an energizing circuit for said clutch, a pair of switches actuated by said machine, said latter switches being adapted to establish a maintaining circuit for said clutch independently of said former switches and being adapted to close successively and open successively, and means for varying the time of closure of said latter switches with respect to each other. 4

6. The combination with a driven machine, of an electro-magnetic clutch for transmitting power thereto, a plurality of normally open push buttons adapted while simultaneously depressed to maintain an energizing circuit for said clutch, a plurality of switches actuated by said machine, said switches being adapted to close successively and open successively, whereby one of the same is adapted to establish a maintaining circuit for said clutch following initiation of the cycle of operation of said machine and nausea the other is adapted to interrupt said maintaining circuit upon completion of the cycle of operation of said mac me.

nection of said elements, a circuit for said member, a plurality of relatively widely spaced manually controlled switches adapted during simultaneous closure thereof to effect uninterrupted energization of said circuit, and means contro led by said driven element to automatically maintain said electromagnetic member energized fora given period to thereby permit tempora release of "said manuall controlled switc es during each cycle 0 operation.

8. In a safety device for presses and the like having a predetermined cycle of operation, the combination with power operated driving and driven elements, an electromagnetic clutch for connectin and disconnecting said elements, clutc controllin means comprising a circuit and ri ht-han I and left-hand switches adapted while jointly closed to efiect and maintain energization of said circuit, and an adjustable limit switch controlled .by said driven element and adapted to provide an alternative energizing circuit for said clutch only during a predetermined portion of said cycle of operation to thereby permit temporary release of said right-hand and left-hand switches.

9. In a safety device for presses and the like having a predetermined cycle of operation, the combination with power operated driving and driven elements, an electromagnetic clutch for connecting and disconnecting saidelements, clutch controlling means com rising a circuit and right-hand and leftand switches adapted while jointly closed to initiate and maintain said cycle of operation, a. plurality of sequentially closed and sequentially opened limit switches controlled by said driven element and adapted to provide an energizing circuit for said clutch independently of said first mentioned switches during a predetermined portion of said cycle of operation, and means for increasing or decreasing the portion of said cycle of operation sub'ected to automatic 1 control by said limit swltches.

In witness whereof, I have hereunto sub- 55 scribed my name.

' FREDERICK H. OBERSGHMIDT.