RU56601U1 - CRANE SCALES - Google Patents

Abstract

Relate to the field of hoisting and transport machinery, namely, devices for weighing goods on cranes, which are designed to work with four-rope clamshell mechanisms, electromagnets or hook suspension. Crane scales contain two load cells located in protective housings. The sensors are interconnected by means of a jumper and axles with the possibility of free movement in a vertical plane relative to each other, and mounted in a chain of cargo closing ropes. The design of the crane scale provides improved accuracy in measuring the mass of the load being lifted.

Description

The utility model relates to the field of hoisting and transport machinery, namely, devices for weighing goods on cranes, which are designed to work with four-cantilever clamshell mechanisms, electromagnets or hook suspension.

A known device for weighing cargoes (RF Patent No. 2119648, G 01 G 19/14, prior. 04/18/97, publ. 09/27/98), which contains a lifting and transport mechanism with load sensors installed on it, which are electrically combined with amplification the transforming unit, and their bases are spring-loaded.

The disadvantage of this device is the rigid structure, which entails a change in indicators during the redistribution of the mass of the cargo, and the uneven stretching of the cargo ropes, which leads to an error in the weighing results.

The closest to the claimed crane scales (Patent of Ukraine 19749, G 01 G 19/14, prior. 12/23/92, publ. 12/25/97, bull. No. 6), which contain a transmitting lever and a balancer made in the form of two cheeks, in in the middle of which are two spring-loaded force measuring sensors connected by an electric circuit to a secondary measuring device.

The load from the mass of the lifted load is transmitted to the sensors through the cheeks. In the process, due to the torsion of the cargo ropes under load, a longitudinal displacement of the cheeks relative to the axis of rotation occurs, the effect of friction arises, which leads to low accuracy in determining the mass of the lifted load. In addition, the presence of a spring that holds the sensors in their original position also leads to a change in the readings of the balance during operation due to its natural wear.

The utility model is based on the task of improving crane weights, in which by modification in placement

force sensors provides an increase in the accuracy of measuring the mass of the lifted load.

The problem is solved in that the crane scales, which contain two load sensors connected by an electric circuit to a secondary measuring device, in accordance with the utility model, load sensors placed in protective housings are interconnected by means of a jumper and axes with the possibility of free movement in vertical plane relative to each other, and mounted in a chain of cargo closing ropes.

A causal relationship is as follows.

The placement of load cells with the possibility of free movement relative to each other in a vertical plane, allows you to perceive the entire mass of the lifted load and obtain a weighing result with an accuracy of 0.1% of the maximum weighing limit.

Crane scales mounted in the chain of cargo closing ropes allow you to get an accurate weighing result that is not affected by side loads, vibrations and uneven stretching of the cargo ropes.

The essence of the proposed utility model is illustrated in the diagrams, where:

figure 1 is a General view of crane scales,

figure 2 is a top view.

The balance contains two strain gauge sensors 1 in the form of plates, which are fixed in protective housings 2 between the upper ears 3, the covers 4 and the lower ears 5 with bolts 6. Both protective housings 2 are interconnected into a single structure using a jumper 7, axles 8 and the connecting part 9. The cable 10 from the sensors 1 are laid inside the jumper 7 and exit through the pressure glands (not shown) to the compartment 11 with the cover 12, where the analog-to-digital converter (ADC) (not shown), the radio transmitting unit (not shown) and the antenna 13. In

compartment 14 with a sealed cover 15 contains replaceable batteries (not shown) for powering the sensors 1.

Crane scales work as follows.

Crane scales, through the upper ears 3, are mounted in the closing ropes of the crane’s cargo winch at the place of their regular connection with the grab mechanism pulley, and the ropes of the grab mechanism pulley are mounted to the scales through the lower ears 5, while the scales should be in the visible horizon. After loading of the clamshell mechanism and its complete separation from the ground by the closing ropes, in which the crane scales are mounted, the lifting stops, while the retaining ropes of the clamshell mechanism remain unloaded (a slight sagging within the boundaries of 1-2 chain links). In this case, the entire load (force F) is directed to the closing ropes with crane weights. In this state of the grab (within 5-10 seconds), the crane driver receives the weighing result on the display of the digital electronic terminal, after a confirmation sound signal of the weight is fixed, the result is recorded and recorded in the adder, after which the holding ropes are pulled to the transport position and the grab moves to the place of unloading.

The force F from the mass of the load that rises through the threaded part of the lower ears 5 is transmitted to the strain gauge sensors 1. Moreover, due to the connecting part 9 of the protective housings 2, the jumpers 7 and the axes 8, both sensors 1 are able to freely move relative to each other in the vertical plane, within the boundaries of at least 15 ° without changing its vertical position, which allows the sensors to perceive the entire mass of the lifted load with two closing ropes, which are not affected by side loads (uneven stretching cargo ropes, uneven operation of the grapple chain hoist, etc.). In the ADC, the voltage is processed and amplified to the required value. Further, processed, amplified, filtered out from interference and

the signal converted into a digital form is fed to the input of a radio transmitting electronic unit, and from there, using an antenna 13 it is transmitted to a digital electronic terminal. In a digital electronic terminal, a signal is received, its processing and information about the load goes to a liquid crystal display, the radius of the radio channel is at least 100 m.

Claims (1)

Crane scales containing two load sensors connected by an electric circuit to a secondary measuring device, characterized in that the load sensors placed in the protective housings are interconnected by means of a jumper and axes with the possibility of free movement in a vertical plane relative to each other and are mounted in a circuit freight trailing ropes.