DE647658C - Control for electric motor drives of scissors - Google Patents

Description

The invention relates to a control for the electromotive drive of a pair of scissors, which is tempered for each cut and which the rolling stock at a variable speed is fed from the roll stand. A touring dynamo is coupled to the roll stand or to the drum roller motor, which influences the control apparatus for the scissors drive in such a way that despite being changeable Feed speed, the same lengths can be cut.

Measures for cutting the same length are with continuous rotating shears has already been applied. The speed of the traversing scissors is here made dependent on the rolling stock speed. There are a number of Solutions become known. They are based on the fact that the speed of the safe accordingly the fluctuations in speed of the last roll stand, from which the bar runs out to the shears, is regulated. Since the Cutting lengths depend on the speed of the shears and the speed of the rolling stock equal lengths are achieved if these factors match. With these The scissors run through arrangements the whole time.

In another version that has become known, the scissors are run through after each Rod that has been divided into intermediate lengths stopped and before entering of the new rolling rod from a very specific position of the scissors knife started again. That’s the purpose of a to be able to cut off a short head piece of the rod (scooping). The scissors keep this but the peculiarity of a continuous pair of scissors.

Scissors that are started from a standstill for each cut are different Considerations for maintaining the same cutting lengths are decisive. For the cutting accuracy the time of actuation of the control organs for the scissors comes into consideration first and foremost. The command to Cut is given by a stop flap or photocell or some other switch, the distances corresponding to the desired cutting length behind the scissors. Since the scissors require a certain amount of time from the time of the command to the cut, during the the rolling rod continues to run at a variable speed, it is clear that there are differences must occur in the cut lengths. To counter this disadvantage, can the time between the issuing of the command and the actuation of the shears depending on the rolling stock speed

*) The patent seeker stated as the inventor:

Dipl.-Ing. Paul Paech in Duisburg.

Claims (2)

bring goodness. At higher speeds, the cut is made earlier, at lower speeds Speeds later. The invention is concerned with a simple advantageous way to accomplish this reach. The control for electrically operated scissors, each for. Cut out are started to standstill, namely is formed so that the voltage or The frequency of the tour dynaroo influences the control coil of the switch-on contactor, its response time is variable according to the applied voltage or frequency. Another possibility of the invention is seen in the fact that the voltage or frequency of the touring dynamo controls a magnet that consists of a photoelectric Cell or other electrical switching means existing control device for switching on the control motor spatially shifts. In the drawing, two embodiments of the invention are shown in Figs. In Fig. Ι 1 means the single drum roller motor. The touring dynamo is denoted by 2 and a control contactor is denoted by 5. At high voltage, the switching time of the contactor 5 is short; at low voltage, the switching time is longer, because at low voltage, over ¹ winding of the magnetic inertia requires more time. A scissor motor can be switched on by means of a contactor even with air-driven scissors, the air valve via this contactor by means of magnets controlled accordingly. In Fig. Ι 6 denotes such a lifting magnet for controlling this air valve. This lifting magnet is also attached to the same Voltage and responds faster or slower depending on the voltage level. This switching arrangement achieves that at high speed the voltage is high and thus the switching time is short. If the speed is low, the voltage is also low and with it the switching time higher. In Fig. 2, 11 denotes the rolling motor, the touring dynamo and 17 a Kornmando apparatus, z. B. a photoelectric cell. A magnet 15 is connected to the touring dynamo. The light switching relay 17 is coupled to the magnet 15, the voltage is If the touring dynamo is higher, the magnet is drawn in, the light switching relay is closed after the roller line, i.e. H. the switching command is given earlier,. so that in this case with the same tax time between command and cut the cut through the displacement of the command apparatus takes place faster, so also as above, the changes in the number of revolutions of the rolling motor are compensated. Ρλτε ντ α χs ρ rf cue: ι. Control for electric motor drives of shears, which the rolling stock is fed at a variable speed from the roll stand, and one with the roll stand or with the Compactor motor coupled Tourerfdynamo influences the control apparatus for the scissors in such a way that despite changeable Feed speed, the same lengths are always cut, indicates that the voltage or frequency of the touring dynamo controls the control coil of the contactor for the Scissors motor or for another control element of the scissors affects its response time according to the applied Voltage or frequency is variable. 2. Control according to claim 1, characterized characterized in that the voltage or frequency of the tour dynamo controls a magnet which controls the control device consisting of a photoelectric cell for the activation of the scissor motor. 1 sheet of drawings