TNSC is proud to present its idea of a multi-purpose light lift system called MPLS. Valuing thirty years of know-how in the mechanical and electronic field, a lifting system has been created that concentrates, in a very compact space, the characteristics of safety, simplicity, control and energy saving. The system is basically composed of two simple but at the same time highly technological elements. The first is represented by an “S” type load cell. The second is a compact motor-reducer with an orthogonal output, on which two T10 toothed belt pulleys are fitted. The load cell “S” type, used in traction, is able to support 500Kg in steady state with a breaking load equal to 1,500 Kg. The cell is interposed between the anchoring system to the structure and the motor-reducer body / pulleys. In this way the cell weighs the lifted bodies in an accurate and linear way, without interpolations to determine the weight according to the height (the weight of the system will be subtracted at the time of calibration).
Below the cell there is a compact motor-reducer (0.18 KW motor and reducer with worm screw and output of the orthogonal secondary shaft). Two toothed pulleys (one for each side) are fitted with two toothed pulleys (diameter 100 mm and width 25 mm) for toothed belts model T10 / 25 mm (on request it is possible to use pulleys and 32 mm wide belts to support an increase of 30% load). Each tooth in the grip is able to support a weight of 10 kg; the system foresees that for each pulley 16 teeth are constantly engaged, allowing a maximum nominal load of 320 Kg. The workload is deliberately blocked at 65 Kg, but can be changed through the “Settings” menu of the control board, until to a maximum of 120 Kg (160 Kg for systems with pulleys / belts of 32 mm). The toothed belt is collected by means of a reel with mechanical return. At the end of the straps is fixed a practical anchoring system (which allows to support a 38 mm diameter tube or a mini truss connection) and an electrical junction box to connect lighting bodies or for audio and video reproduction.
Why also the load cell and the toothed belt? The use of load cells instead of the classical over and under load reading systems has not yet been adopted as a main system by the major manufacturers of lifting systems, both for the additional cost of the components, and for the complexity in the management and set-up. • Current weight measurement systems include a group consisting of two coaxial springs for each rope / band, one for overload and one for under load; or in the case of use of load cells, they provide a linkage composed of a cell (normally bending) for each rope / band. The replacement of the spring assemblies involves the use of 2 or more cells, and requires complex electronic management. In particular, the variability of the load weighed during movement (collection of the flat or spiraled cable or of a flip-flop with metal structure) involves complex calculations according to the position, with consequent increase in the measurement uncertainty. TNSC has taken an innovative path, replacing the load reading system with a single traction cell. The cell is positioned immediately below the anchor plate and detects the weight of the applied load plus that of the system. The weight of the latter is then subtracted in the calibration phase. This allows you to accurately weigh the lifted load and to determine the limits within which the system will react to load variations. If during the journey the control system reads a weight increase> = of 5 Kg or a weight decrease <= of 5 Kg, the system stops immediately.
Beyond this efficient load reading system, the MPLS uses a traction system that keeps the applied torque constant. Traditional systems, both when using round ropes and flat metal strips, have a variable use torque. In fact the ropes are rolled up on themselves in a spiral system, inducing an increase or a decrease of the useful arm during the movement. This implies a variation of the torque, with particular loss of the lifting force available near the Top Limit, a variation of the speed and length of the rope for each revolution of the driving shaft (spiral effect). The solution used by the TNSC instead allows you to have constant torque and speed and equal elongation of the ropes for each revolution of the driving shaft, whether you are at the Bottom Limit or the Top Limit. Furthermore, the toothing of the belt does not allow sliding between the two sides. The shape and width of the belts confer rigidity and stability both on the orthogonal axis and on the longitudinal axis, quickly dampening the pendulum effect
So why multipurpouse …. The MPLS is designed to operate as a single shot or as a group (up to 4). This allows the creation of a very efficient linear lifting system (electric axis) or dislocated for lifting complex structures (triangular, circular or square type advertising boards). The strengths, for this type of configuration, lie in the very accurate load reading (100 g) and in the constant movement determined by the toothed pulleys / belts unit. This allows you to suddenly stop the movement in case of changes in the load beyond the preset safety limits (all the parameters can be changed via software). The lower anchorage system also allows you to choose the best solution depending on the load. For example, it is possible to fix an additional anchoring system between the free ropes, in any position, allowing to hook additional loads (eg loudspeakers) to avoid the use of uncomfortable and heavy drop-arm. .