DE1049555B - - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

PATENT DOCUMENT 1049 REGISTRATION DAY:

NOTICE THE REGISTRATION AND ISSUE OF THE EXTENSION CHRIFT:

ISSUE OF PATENT LETTERING:

DEP 1Θ49555

INTERNAT. KX. B 66 C 2 May 9, 1957

29 JANU A V-1959 July 23, 1959

AGREES ABOVE WITH EXIT 1 049 555 (K 32094 XI / 35 b)

The invention relates to a load torque switching device in which the crane outreach and the size the load can be measured separately. If the product of both values exceeds a specified limit, then the hoisting gear is lifted in the direction of lifting and the luffing gear is luffed out in the direction of the luffing switched off. The known devices of this type mostly work mechanically. For example can adjust the position of the boom and the size of the load measured using a scale two carriages can be used. There is a limit switch on one slide and a stop on the other appropriate. The transmission gears are arranged so that at a fixed product of the two Drive the measured values past each other and switch off the engines. One has already, instead of To use a stop, both contacts are attached to components that can be moved relative to one another. Mechanical devices of this type have in common that they are quite cumbersome to install are and therefore become expensive. You can consistently only use a certain type of crane with a constant Cantilever length and footprint are used.

It has already been proposed to measure the reach and load size using a potentiometer. The invention relates to a further development of this proposal, the potentiometers being replaced by small ones Measuring transformers that can be attached to different measuring points independently of one another. Two such transformers are placed between an alternating current source with constant voltage and one Switching device switched on. The transmission factor of the measuring transformers can - if this z. B. off Coils and these displaceable cores exist - change by moving the core, so that the output voltage is reduced by the product of the transmission values set for both transformers is available on the switching device. In order to get the most accurate result possible, Transformers with a linear transmission characteristic are used, i. that is, if the core is the same Lines shifts, then the transfer value also changes by the same amount. Measuring transformers, the have a linear characteristic over at least part of their measuring range have already been developed, and these devices can be used here so that only the linear range is used for the measurement Is used.

The crane outreach can be z. B. measure that one in the area of Orucklenkerlagers attaches a reduction of the boom system and couples it with the DruckLenker. The free end of a fly jib reduced in this way is then also guided horizontally. His distance Load torque dialing for cranes, especially jib cranes

Patented for: Krupp-Ardelt G.m.b.H., Wilhelmshaven

Karl Hennig, Wilhelmshaven, has been named as the inventor

from the bearing axis is always proportional to the actual projection on the beak roll. This free one The end can therefore optionally be connected directly to a displaceable core of a measuring transformer will.

It is a little different - this is the case with cranes with a single-joint boom. But here you can also use the projection Measure quite precisely if you only measure the horizontal distance of a section of the boom or its Taps extension from the boom axis. For example, an articulated parallelogram can be attached to the boom with a perpendicular base, a rod of this parallelogram with the direction of the Boom matches. Is then between the movable vertical rod and the core of a transformer a longitudinal guide is interposed in the direction of the rod, then the core is always horizontal here too proportional to the outreach measured from the boom bearing. The measuring transformer for the load can be adjusted in various known ways. This can e.g. B. with one on the hook block attacking double rope strand happen that one. the free end of the load rope on one The spring hangs up and the spring deflection is transferred to the transformer core, the load rope that is guided between two pulleys deflects via a spring-loaded further Umlenkroüe or supports the hoist itself resiliently.

The input voltage for the first transformer should be kept as constant as possible. B. over a resistance in the input circuit can take place. This resistance can also be used in Adjust automatically depending on the existing voltage, or you can use any of the known ones Use circuit arrangements to keep the input voltage constant, but in any case

-Λ9 553013

Claims (9)

should be less than the lowest possible voltage available. Another resistor can be attached in the measuring circuit to calibrate the switching device, and this resistor also makes it possible to use the same measuring device without any changes for very different types of cranes, if the permissible load torque is related to the boom foot bearing. Only the transmission linkage, measuring springs or the like could change. Furthermore, the use of measuring transformers has the advantage that they can be attached to practically any otherwise unprotected place. For this purpose, z. B. completely embed the transformer coils in molded material, and you can also accommodate the transformer itself in a waterproof housing, the measuring movement on the core through a stuffing box or better still through a membrane. The shape of the measuring transformer is not decisive. In particular, as is finally proposed, rotary transformers can also be used if the measurement is expediently carried out as a rotary movement. The explanatory drawing shows, for example, Fig. 1 a circuit arrangement according to the invention, Fig. 2 the arrangement of the measuring points on a double jib crane, Fig. 3 on an enlarged scale a measuring point for the load, Fig. 4 also on an enlarged scale the measuring point for the projection according to FIGS. 2 and 5, a corresponding measuring point for a jib crane with a single-articulated jib. If it is assumed that a voltage U1 is available at terminals 1 in FIG. 1, then this voltage can be reduced to a primary voltage U2 for a first adjustable measuring transformer 3 via an adjustable resistor 2. The adjustment of the resistor 2 can, if necessary, take place automatically as a function of the voltage U1. The secondary coil 3 b is short-circuited with the primary coil 4 a of a further measuring transformer 4, so that the voltage U3 at the transformer 4 is converted into a voltage U 4 of the secondary coil 4 & according to the respective transfer value of both transformers. This voltage could be measured directly on a measuring device 6 with the interposition of a rectifier 5. The measuring device can be calibrated by a further adjustable resistor 7, and by a correspondingly large adjustment range of the resistor 7 it can be achieved that the overall electrical arrangement can be used for practically all possible crane types, dimensions and loads without changing the individual devices. In addition to displaying the load torque, this measuring device can also be used in a known manner to switch off when a specified torque value is exceeded. It is expediently designed as a moving coil relay. One accepts. that the transformer 3 is adjusted depending on the size of the load, then it is still possible to separately tap div voltage U 3 and use it for display, possibly also for weighing and registering the conveyed load. According to FIG. 2, the hook block 8 is held by two rope strands, the free end of the load rope 9 being attached to the fly jib 11 at 10. There you can measure the rope force and thus also the load. For the measurement of the projection 12, a reduced Doppeilenkersysteni is connected at 13 to the pressure link 14 and between the Druckienkerlager and the traction arm bearing 16 at 17 on the support frame. The end 18 of the reduced fly jib 19 executes the same, correspondingly reduced movement of the beak roller 20 in the fly jib 11. The path of point 18 can then be transferred directly to measuring transformer 4. According to FIG. 3, at 10, the load rope is attached to a punch 23 which is supported on the fly jib 11 via a spring 24. The movement of the ram corresponds to the spring travel or the load size and can therefore be transferred directly to the core 3 c of the measuring transformer 3. In Fig. 4 the connection of a stamp 4 c of the measuring transformer 4 at 18 to the reduced jib arm 19 is shown again. The projection 22 of the point 18 is proportional to the actual projection 12 of the beak roll 20 at any moment. As FIG. 5 shows, when using a single-joint boom 26 this can have a rear extension 26a. With further rods 27, 28 and 29, the extension 26a forms an articulated parallelogram, the rod 27 of which is fixed in the cantilever bearing 15a and in a further bearing 30 in the vertical direction. Therefore, the horizontal distance 22 α is proportional to the projection 12 o at every moment. The core 4c of the measuring transformer 4 is here connected to the rod 29 via a longitudinal guide 31 by means of four rollers. Patent claims: 1. Load torque switching device for cranes, especially jib cranes, with a switching device, which responds when the product of the separately measured electrical values for the load and for the projection exceeds a specified value, characterized in that between an alternating current source (1) with constant voltage and the switching device (6) two controllable Measuring transformers (3, 4) are switched on, the transmission factor of which is proportional to the Size of the load and the load distance is regulated. 2. Device according to claim 1, characterized in that the measuring transformers (3, 4) made of coils and displaceable with respect to them ·.! Cores (3 c, 4 c) exist, being used in the Measuring range of the transmission factor with the same immersion paths of the cores (3 c, 4 c) in the Coils enlarged by the same values. 3. Apparatus according to claim 1, characterized in that a double-link luffing cranes Reduction of the boom system coupled with the pressure control arm (14) in the area of pressure handlebar bearing (15) arranged and used to control the measuring transformer (4) for the crane outreach is. 4. Apparatus according to claim 1 or 2, characterized in that in cranes with pressure boom this via a joint parallelogram and a vertical guide the core (4 c) of the measuring transformer (4) for the crane radius adjusted proportionally to the radius. 5. Apparatus according to claim i or 2, characterized in that the adjustment of the measuring transformer (3) is effected for the load against a spring (24) correspondingly influenced by the load rope. 6. Apparatus according to claim 1 or 2, characterized in that adjustable resistors (2, Ύ) for regulating the input voltage and / or the cut-off voltage for the switching device are provided. 7. Apparatus according to claim 1, characterized in that the transformer coils are completely in Molded material are embedded. S. 8. Apparatus according to claim 1 or 7, characterized in that each transformer in a water sealed housing is housed and that the transmission of the measuring movement to the core takes place through a stuffing box or a membrane. 9. Apparatus according to claim 1, 7 or 8, characterized in that rotary transformers come into use. 1 sheet of drawings ® <K »747i133 1.59 (909 563/315 7. 59)