DE1121180B - Monitoring and control circuit for punching machines, perforating machines, etc. like - Google Patents

Description

GERMAN

PATENT OFFICE G 05 g; H 02 ρ

U 4361 VIIIb / 21 c

REGISTRATION DATE: FEBRUARY 7TH 1957

NOTICE THE REGISTRATION AND ISSUE OF EDITORIAL:

JANUARY 4, 1962

The invention relates to a monitoring and control circuit for punching machines and perforating machines or the like

In the known punching machines, a workpiece or material to be punched is placed on a workpiece carrier Machine and a punch knife is then placed on the material to be punched at the selected punching point. A press beam or punch arm is then pivoted around a support post and over the punch set, whereupon a gear is switched on, which gives the punching arm a punching stroke. After the punch knife has been driven through the material to be punched, a counter stroke is initiated and the punching arm is brought back to its upper position. It has also been suggested for the transmission to provide a control circuit for executing the punching and counterstroke, which ends the punching stroke and initiates the counter stroke as soon as the punching knife penetrates the material to be punched and a conductive one Touches the surface of the workpiece pallet. The punching stroke of the punching arm is independent of the The thickness of the material to be cut and the height of the cutting knife are controlled. This principle can also be used on perforating machines or the like. Can be used.

Many types of machines equipped with such controls are operated by operating a Switch lever switched on, this lever also switches on a monitoring circuit that automatically changes the work flow of the machine in response to a specific event. In many cases it is Change in the course of work dependent on the monitoring circuit is so important that a failure this monitoring circuit can result in great damage or even accidents.

The solution to the problem of providing effective accident protection is the purpose of the invention. For example, the control circuit is built into a known punching machine so that a fuse for normal work and a jamming of the punch knife or an injury of the worker, should his hand be between the punching arm and the workpiece carrier, avoided will. Furthermore, the invention can be used for purposes other than changing the work flow of a machine to bring about serve, which are indispensable for the safety of the worker operating the machine are, such as B. preventing a machine from starting in the event of failure of the monitoring circuit or to operate protective or triggering devices.

The invention therefore relates to a monitoring and control circuit for drives Monitoring and control circuit

for punching machines, perforating machines

and the like

Applicant:

United Shoe Machinery Corporation, Boston, Mass. (V. St. A.)

Representative: Dr.-Ing. H. Fincke, Berlin-Lichterfelde, Dipl.-Ing. H. Bohr and Dipl.-Ing. S. Staeger, Munich 5, Müllerstr. 31, patent attorneys

Claimed priority: V. St. v. America 9 February 1956 (No. 564 504)

Robert Whitney Bradley, Marblehead, Mass.

(V. St. A.),
has been named as the inventor

of punching machines, perforating machines and the like with a conductive workpiece carrier plate, a self up and down moving punch arm with a conductive punch, one of which is a conductive Punch knife is pressed through a workpiece located on a workpiece carrier, a switching lever initiating a punching stroke and an electronic control that controls the punching stroke ends and initiates a counter stroke as soon as there is a reduction in resistance between the workpiece carrier plate and the punch arm takes place below a predetermined value. After the essential The feature of the invention is the monitoring function of the controller containing two tubes temporarily transferred to an interruption circuit, so that if the controller is unable to to exercise their monitoring function, an excitation circuit cannot be closed and none The punching stroke is initiated until the control interrupts the circuit by energizing a relay. A line in the circuit of the tubes, leading through the contacts of a relay, is in the normal position grounded, so that the voltage of a grid of the tube is diverted and the control is excited To interrupt the interruption circuit by energizing the relay.

109 758/425

3 4

According to the invention, by energizing which is connected to the valve piston 28, when a relay is energized a relay in a delay circuit pulls the valve piston into its lower position,
energized, the input circuit of the tubes disengaged, the control circuit for initiating a punching the circuit from the power source to the anode hub is temporarily interrupted with a switch 42, the switching lever of the tubes and the interruption circuit in front of the 5 44 is located on the front part of the punching arm 18, with it a punching stroke is provided. The downward movement of the switching sequences can. hebeis 44, the solenoid 40 is supplied with alternating current

To do this, the tubes energize the relay, so that the lines 46 and 48 are connected. Four relays 50, 52,

Contacts open, the holding circuit to relays 54 and 56 are connected to the control circuit,

and the excitation circuit to the solenoid under- io By operating the shift lever 44, the

are broken and a counter stroke of the punch arm relay 50 in a circuit that is from the line

is initiated. So it is the monitoring 46 through relay contacts 56 a, the switch 42 and

function of two tubes temporarily on a sub- the winding of the relay 50 leads to the line 48,

breaking circuit transmitted so that when turned on. Energizing relay 50 causes a

the tubes are unable to monitor their 15 delayed energization of relay 52. The relevant

exercise function, an excitation circuit is not activated. Circuit runs through switch 42,

are closed and do not initiate a punching stroke contacts 50 a and over the winding of the relay 52

can, until the tubes by energizing a relay to the line 48. To delay the closing of the

Open the interruption circuit. To reach relay 52, a capacitor is used as a secondary

Furthermore, a relay is provided, the winding 20 of which is attached to the relay coil 52 in a circuit. Except-

connected in series with the filaments of the tubes are a resistor and a rectifier in

and when it is excited the circuit is connected to the series in the circuit (see Fig. 1). To

The anodes of the tubes via contacts closed when energizing the relay 52 is used for holding the

is so that voltage is only then formed to the anode relay 50 a circuit. This holding

The tubes are routed when the filament 25 circuit goes from the bottom of the line 46

are intact, making the possibility of opening through contacts 54 a and 52 d to the coil of the

of the interruption circuit through persistent relays 50 and back to line 48. Simultaneously

Heat radiation (when the filaments are turned off, an excitation circuit for the solenoid 40,

are on fire) is excluded. In the drawing from the same point the line 46 through contacts

Connections is 30 SAb and 52c to solenoid 40 and line

Fig. 1 is a schematic representation of the going into a 48, closed.

Machine built-in monitoring and control The circuit diagram shown at the bottom left in Fig. 1

circuit, forms the monitoring circuit for ending the

Fig. 2 is a side view of a switch-on punch stroke. Two gas discharge tubes 60, 62 inside

device according to another embodiment than that in Fig. 35 half of this circuit are normally non-

Fig. 1 shown, partially in section. conductive and are discharged one after the other by

As shown in Fig. 1, the machine has a control pulse on a control grid 64 of the tube 60 known punching table 10 is transmitted with an electrically conductive, the result of a counter-workpiece carrier plate 12, which was made of conductive rubber 68 containing current source can and serves as a support surface of the plate 40 circuit either via contacts 52 b of the relay-like stamped goods 14 made of leather or the like, from 52 or via the contacts 50 c of the relay 50 when the tubes 60 are unloaded by means of a freely movable punching knife 16 and 62 are closed and the workpieces are punched. A punch arm or relay 54 is energized. Thereby, the Kon-pressing bar 18 with the also conductive stamping are contacts 54 α and open b 54 and the holding circuit dies 19 are mounted on the punching table 10 swingably 45 for relay 50 and the excitation circuit to and perform the up necessary for punching coil 40 interrupted, whereby the punch 18 in and downward movement, the punch knife is moved back to its starting position. The Zu-16 is pressed through the workpiece. To ensure that the punching arm moves back safely, for reasons of clarity, the punch 19 is insulated from the punching arm 18 to reduce the electrical resistance. 5 ° of the workpiece carrier plate 12 and the punch

The up and down movement of the punch arm 19 is achieved below a predetermined value. The-18 is preferably operated hydraulically. As in this value can be set so that it is based on the Fig. 1 indicated by dotted lines, is a moment in which the punch knife 16 on the with a support post for the punching arm 18, the workpiece support plate 12 is tied through the workpiece Piston 22 penetrates within a cylinder 24 55, is precisely matched. One input current movable. A valve piston 28 is in a valve source 70 for the tube 60 is in series with one housing 26 slidably mounted. In the high-quality resistor 72 shown, the one between the Git high position of the valve piston 28 is a lower hole ter and a cathode 74 of the tube 60 is arranged 30 of the cylinder 24 is connected to a supply line 32. This will normalize the tube 60 and an upper hole 34 of the cylinder 24 with a 60 wise held non-conductive. The workpiece carrier emptying line 36 connected so that the piston plate 12 and the punch 19 are as a secondary 22 is moved upwards. Arranged in the lower position of the valve connection and thus form a high piston 28 are the connections of the lines of valued resistor. This resistance between 32, 36 reversed, so that the piston 22 acts after the stamped parts as a control voltage 'on the moved down. The valve piston 28 is supported by a 65 grille 64 so that while reducing this Spring 38 in its normal position, the high position, increases the resistance of the grid voltage 64 hold so that the punch arm 18 is usually turned on. The circuit in which the mentioned punched lifts is. A solenoid 40, whose armatures are connected to parts, is not in the drawings

shown. This indicates the end of a punching stroke, and the tube 60 becomes conductive. The charge on the cathode 74 is transferred through a delay circuit 80 to a grid 76 of the tube 62, causing that tube to conduct and the relay 54 to be energized. This switching arrangement serves the purpose of initiating the upward movement of the punching arm 18 not only when a punching stroke has ended, but also when a part of the worker's body should come between the punched parts during a punching stroke. For this reason, it is very important to provide a monitoring circuit which is able to perform its control function of opening the contacts 54 α and 54 b.

For this purpose a switching arrangement is provided which prevents the machine from being switched on, by breaking the switch-on circuit if the monitoring circuit should fail. By energizing the relay 56, the contacts 56 a of which are arranged in series with the switch 42 are, the contacts 56 a are opened. This prevents the relay 50 from being energized, and switching on and starting the machine is impossible. A second possibility is shown in FIG. 2 shown by blocking a movement of the shift lever 44 a by energizing a solenoid 82 will.

Relays 50 and 52 are used to temporarily transfer the control function of the monitoring circuit to the described interruption circuit. When these relays are not energized, they are in the position shown in FIG. If the relay 54 is also not energized, a circuit leads from the line 46 through the contacts 54b and 50 (/ and the coil of the relay 56 to the line 48, whereby the relay 56 is energized with the cathode 74 in the shunt, and by grounding the negative side of the input power source any existing voltage is derived. Thus, ie, from the relay 50 on the basis of contacts 50, the monitoring circuit b excited to acquire its control function. then, if not failed, the monitoring circuit, but as provided works, the circuit to relay 56 (or to coil 82) is interrupted so that the control circuit can initiate a punching stroke.

As can be seen, the relays 50 and 52 represent a switching arrangement which, after the control circuit has been switched on , closes the circuit to the power source (lines 46 and 48) through the contacts 54 b within the excitation circuit to the coil 40. At the same time, the bias power source is no longer grounded so that the monitoring circuit can perform its normal function.

The starting position of the circuit is shown in FIG. Once the main switch MS is closed, the interrupt circuit of the line 46 by the contacts 546 and 50 d and the relay coil 56 to the line 48 is closed. Only after the tubes 60 and 62 become conductive, the interruption circuit being opened by the relay 54, the machine can perform a punching stroke. Should any failure of the tubes or other parts occur so that the monitoring circuit cannot energize the relay 54, the machine will be unable to perform a punching stroke. When the monitoring circuit is functioning, however, each time the switching lever 44 is actuated, the relay 50 is energized, which a) energizes the relay 52 via a delay circuit, b) disconnects the input current source for the monitoring circuit, c) the anode voltage of the tubes 60, 62 and thus the ionization process interrupts and d) opens the interruption circuit. Shortly thereafter, the relay 52 is energized, which closes the circuit for the anode voltage of the tubes, the excitation circuit to the coil 40 and the holding circuit to the relay 50. In this switch position the monitoring circuit controls the drive circuit. Likewise, when the relay 52 is energized, contacts 52 a are closed, whereby the monitoring circuit is connected to the punch 19. If desired, however, the punch 19 can be connected directly to the resistor 72 without this connection leading through the contacts 52 a.

As a further safety measure, the current source 69 containing the resistor 68 is provided with a Relay 90, whose contacts 90 a in series with the direct current source for the anode voltage of the tubes, a rectifier 92 connected. The armature of this relay 90 is in series with the Filaments of the tubes 60, 62 connected so that by the energized by a transformer 94 relay Anode voltage is only applied to the tubes if the heating filaments are intact. The relay 90 interrupts the anode voltage as soon as the filaments are damaged, thus the possibility of one opening of the interruption circuit is eliminated by continuous heat radiation.

Claims (5)

Claim E: 1. Monitoring and control circuit for drives of punching machines, perforating machines and the like with a conductive workpiece carrier plate, an upward and downward moving punch arm with a conductive punch from which a conductive punch knife is pressed through a workpiece located on a workpiece carrier, a a punching stroke initiating switch lever and an electronic control that ends the punching stroke and initiates a counter stroke as soon as a resistance reduction between the workpiece carrier plate and the punching arm takes place below a predetermined value, characterized in that the monitoring function of two tubes (60, 62) temporarily on one Interrupting circuit (46, 54 b, 50d, 56, 48) is transmitted so that when the tubes (60, 62) are unable to exercise their monitoring function, an excitation circuit (46, 56 a, 42, 50, 48) cannot be closed and cannot initiate a punching stroke until the tubes (60, 62) open the interruption circuit by energizing a relay (54). 2. A circuit according to claim 1, characterized in that one via contacts (50 c) one Relay (50) leading line in the circuit of the tubes (60, 62) is grounded in the normal position, so that the voltage of a grid (64) of the tube (60) is derived and the control is excited, to interrupt the interruption circuit by energizing the relay (54). 3. Circuit according to claim 1 and 2, characterized in that the energizing of the relay (50) energizes a relay (52) in a delay circuit, the input circuit of the tube (60) and the tube (62) and temporarily disconnect the circuit from the power source the anodes of the tubes (60, 62) and interrupts the interruption circuit, so that a punching stroke he follows. 4. A circuit according to claim 1 to 3, characterized in that the tubes (60, 62) excite the relay (54) so that its contacts (54 a, 54 b) open, a holding circuit to the relay (50) and the excitation circuit to the solenoid coil (40) are interrupted and a counter stroke of the punching arm (18) is initiated. 5. A circuit according to claim 1 to 4, characterized in that a relay (90) is provided, the winding of which is connected in series with the heating filaments of the tubes (60, 62) and, when it is excited, the circuit to the anodes of the tubes (60 , 62) is closed via contacts (90 a), so that voltage is only fed to the anodes of the tubes (60, 62) when the heating filaments are intact, which excludes the possibility of the interruption circuit being opened by continuous heat radiation. 1 sheet of drawings θ 109 758/425 12.61