SE431863B - Arrangement for preventing overloading of a truck of the counterweight type, such as a fork-lift truck - Google Patents

Abstract

A truck of the counterweight type, for example a fork- lift truck, is provided with an arrangement for indicating overloading. The truck is provided with load- bearing members 5 at the front end and with a load indicator at the back end in order to indicate the load on the back wheels 3 and in this way to indicate if these are about to lose their grip on the surface. The back wheels are suspended in a bogie 7. To obtain a reliable indication of the load on the back wheels independently of their rotation during movement, said load indicator comprises a strain gauge 11 on the bogie for measuring load-dependent deformations in the latter. The strain gauge is placed on or near the line between the bogie's suspension points in the longitudinal direction of the truck. <IMAGE>

Description

Instead, according to the invention it is proposed to measure load-dependent deformations in the bogie of the rear axle as stated in the feature in the appended claims.

This brings you directly to the force with which the truck loads the rear wheels, which is why the signal you receive really indicates whether there is a risk of tipping. Where and how the deformation is measured depends to some extent on how the bogie is constructed, but it can generally be said that the measurement should take place on or near the line between the bogie's suspension points and in the longitudinal direction of the truok.

The invention will moreover be described in more detail with reference to the accompanying drawing, in which Fig. 1 shows the truck with the bogie plotted with dashed lines, while Figs. 2 and 3 show the bogie seen from above and from the end with the strain gauge plotted.

Fig. 1 shows the truck 1 with front wheels 2 and rear wheels 3, the mast U for the forks 5 and a load 6. The rear wheels are suspended on a bogie 7 which is shown in more detail in Figs. 2 and 3.

The bogie 7 is suspended in the truck on longitudinal pins 8 and 9, so that it and the rear wheels can rotate about a longitudinal axis in relation to the body of the truck due to unevenness in the ground. The rear wheels 3 sit on rear axles or arms 10, and can rotate about a point at the end of these arms for steering the truck. However, this rotation has not been shown in more detail in the drawing. A strain gauge 11 has been placed on lines between the suspension points of the bogie, for example on the top of the bogie. In this way, deformations in the bogie due to the load on the rear wheels can be measured. If the load drops below a certain level, there is a risk of tipping. The strain gauge is connected to electrical equipment for level indication, which, for example, primarily gives a warning signal and in the event of a continuing falling load on the rear wheels, interrupts the truck's lifting movement on the forks.

Genom au; measure the aeformation on the bogie raw or in the vicinity of the line between the suspension points, you get the most accurate measurement Then the load Then the bogie and thus on the rear wheels. The invention can in principle be used on most types of bogie, whereby it is generally always desirable to measure on or near the line between the suspension points on the bogie.

Claims (1)

8200455-7 PATENT REQUIREMENTS Device for preventing overload in a truck (1) of counterweight type, such as a forklift, with load-bearing means (5) at the front end and a front axle, and a rear axle of bogie type with one at two points (8, 9) bogie (7) suspended in the truck and with steerable wheels, which device comprises a load indicator at the rear of the truck, characterized in that said load indicator has the shape of a strain gauge (11) on the bogie for indicating load-dependent deformations in the bogie (7), the strain gauge (11) being located on or near the connecting line between the two suspension points.