Title of Invention

LOAD CARRYING MEANS FOR CABLE ELEVATORS WITH INTEGRATED LOAD MEASURING EQUIPMENT

Abstract

A load-carrying means (1) for cable-operated elevators comprising an under-loop cable arrangement is equipped with a load measurement device. At least one of the pulleys mounted underneath the load-carrying means (1) is fixed to said load-carrying means by a support structure containing an elastic element (7.1, 16, 22) which is deformed by the load-dependant cable forces exerted on the pulley(s) (9). A single sensor (15, 16) determines the extent of this deformation and produces a corresponding signal representing the weight of the load-carrying means (1) as the input for the elevator control system.

Full Text

Description Load carrying means for cable elevators with integrated load measuring equipment The present invention relates to load carrying means for cable elevators with integrated load measuring equipment, in which the weight force of load carrying means and useful load causes load-proportional deformation of at least one resilient element, wherein at least one sensor detects this deformation and produces, at an elevator control, a signal representing the strength of the deformation and thus the load. Load measuring equipment for load carrying means of elevators have the task of preventing elevator travel with an impermissibly high load and of delivering, to the elevator control, data which enables it to react - independently of the instantaneous load state of the load carrying means - in suitable manner to call commands by elevator users. EP 0 151 949 discloses load measuring equipment for an elevator which is based on the principle that the entire elevator car is supported in such a manner on at least four bending girders projecting from an elevator car base frame that these bending girders experience a load-proportional bending deflection. The bending deflection of each individual bending girder is detected by means of strain gauges. All strain gauges form in common a measurement bridge which delivers a load-proportional analog signal to the elevator control. The described load measuring equipment has some disadvantages. The measuring principle requires four bending girders each equipped with a respective strain gauge or two respective strain gauges, wherein the mechanical tolerances of the bending girders as well as the resistance tolerances and mounting tolerances of the strain gauges have to be closely limited in such a manner that all four bending sensors have the resistance values for the same loads. All four or eight strain gauges have to be individually connected with a central evaluating circuit, which occasions substantial cost. Moreover, the four force introduction points between the base of the elevator car and the bending girders have to be so adjusted in vertical direction when being mounted that an acceptable force distribution is ensured. The present invention is based on the object of creating simple and economic load measuring equipment for loading carrying means of elevators with underslung cable drive, which does not have the above-mentioned disadvantages. The fulfilment of the set object is reproduced in the characterising part of patent claim 1 with respect to its most significant features and in the following patent claims with respect to further advantageous embodiments. The load carrying means according to the invention for cable elevators with integrated load measuring equipment has significant advantages. The detection of the total weight of the load carrying means and thus also the useful load is carried out by means of a single sensor, wherein even eccentrically disposed useful loads are correctly detected by this. Thus, costs for further sensors, for the wiring thereof and for the complicated signal evaluation thereof are saved. The resilient element, the deformation of which - caused by the weight of the load carrying means - is detected by the sensor, is part of the support construction by which the cable rollers are fastened to the load carrying means. Consequently, substantially no additional mechanical constructional elements and no additional insulation space are needed for the load measuring equipment. The resilient element, the load-dependent deformation of which is detected by a sensor, can be conceived for different.forms of loading, i.e. it can be designed as, for example, a bending girder, a tension/compression rod, a torsion rod or, for attainment of greater deformation travels, a compression, tension or torsion spring. Thus, load measuring equipment optimally adapted to different forms of load carrying means can be constructed. Advantageous and economic embodiments of the load carrying means according to the invention with integrated loading measuring equipment can be achieved through use of sensor principles adapted to geometric relationships, environmental influences and, in particular, demands on accuracy. The invention permits use of the most diverse sensors for deformation detection, such as, for example, strain gauges, vibrating string sensors, opto-electrical distance or angle sensors and inductively or capacitively functioning distance sensors. Depending on the form of load carrying means it can be advantageous to allow the two cable rollers mounted below the load carrying means to act directly on a common resilient element. The advantages can be a symmetrical, simple execution of the support construction between cable rollers and load carrying means for improved deformation measurement possibilities. In the case of restrictive geometric relationships in the vicinity of the underlying cable rollers or in the case of selection of specific forms of sensor it can be advantageous to allow only one of the two cable rollers to act on a resilient element. The support constructions for the two cable rollers can in that case be executed as separate and differently formed units and no mechanical connections between these units are required. Such embodiments are made possible by the fact that in the case of the underslung arrangement, in accordance with the invention, of the support cables both cable rollers always experience the same loading. Load carrying means for greater loads are usually equipped with a carrier frame. In the case of such embodiments it is generally of advantage to fasten the support construction or constructions, which contains or contain the resilient element and which supports or support the cable rollers, to this carrier frame. In the case of load carrier means for smaller useful loads, these can be executed as a self-> supporting unit. The support construction or constructions carrying the cable rollers and containing the resilient element is or are in that case in advantageous manner fastened directly to the base construction of the load carrying means. In order to reduce the transmission of vibrations and sound waves from the support cables i to the load carrying means it is advantageous to arrange isolating elements between the load carrying means and the support construction or constructions for the cable rollers. Examples of embodiment of the invention are illustrated in Figs. 1 to 3 and described in more detail in the following description. ) Fig. 1 shows, schematically, the installation situation for load carrying means according to the invention without a carrier frame, with a first variant of the integrated load measuring equipment, Fig. 2 shows load carrying means according to the invention without a carrier frame, with a second variant of the integrated load measuring equipment, and Fig. 3 shows load carrying means according to the invention without a carrier frame, with a third variant of the integrated load measuring equipment. A load carrying means 1 in accordance with the invention, without a carrier frame, is illustrated in Fig. 1 together with the elevator components most important for its function. Two guide rails, at which the load carrying means is vertically guided by means of slide or roller guide shoes 3, are denoted by 2. This load carrying means essentially consists of a base frame 4 with a base plate 5, a car 6 installed thereon, the said slide or roller guide shoes 3 and two cable rollers 9 fastened to the base frame 4 by means of a support construction 7 by way of resilient isolating elements 8. The support construction 7 consists of a bending girder 7.1 and two cable roller supports 7.2. Also recognisable is a support cable 10, which is led from a cable fixing point 11 vertically downwardly, then horizontally through below the cable rollers 9 of the load carrying means 1 and subsequently vertically upwardly to a drive pulley 12 of an elevator drive engine 13. The further course of the support cable 10 from the drive pulley 12 downwardly to a deflecting pulley mounted at a counterweight and from there upwardly to a second cable fixing point is not illustrated here. A vertical and a horizontal load-proportional cable tension force acts on each of the two cable rollers 9. The arrows 14 symbolise the cable rollers loads acting on the cable rollers 9 and thus on the support construction 7 and resulting from the cable tension forces of the support cable. It is readily recognisable that these resultants produce a bending moment in the bending girder 7.1 of the support construction 7 and thus a bending deflection. This bending deflection is detected by a bending sensor 15, for example a strain gauge sensor, which is not explained here in more detail and which produces, as an input for an elevator control, a signal corresponding with the strength of the bending deflection and thus with the overall weight of the load carrying means 1. A second variant of the loading carrying means according to the invention with integrated load measuring equipment is illustrated in Fig. 2. The load carrying means 1 guided at the guide rails 2 by means of a slide or roller guide shoe 3, together with base frame 4, base plate 5 and car 6, are recognisable. The support construction 7 supporting the cable rollers 9 essentially consists of a fastening carrier 17, which is mounted at the base frame 4 by way of resilient isolating elements 8, and two cable roller supports 18. The cable roller support, which is not illustrated and is arranged on the right, corresponds with the cable roller supports according to Fig. 1. The cable roller support 18 at the lefthand side is pivotably fastened to the fastening carrier 17 by means of a bending element 19 and supported relative to the carrier by way of a pressure sensor 16. The pivot mounting of the cable roller support 18 could obviously also be achieved by a pivot axle. The cable roller load 14 resulting from the cable tension forces of the support cable causes a load-proportional pressure force on the pressure sensor 16, which also forms the resilient element and which produces a signal, which corresponds with the total weight of the load carrying means 1, as an input for an elevator control. The pressure sensor can be executed as, for example, a piezoelectric element, a capacitive sensor or a strain gauge element. Fig. 3 shows a third variant of the load carrying means according to the invention with integrated load measuring equipment. The load carrying means 1 guided at guide rails 2 by means of a guide or roller guide shoe 3, together with base frame 4, base plate 5 and car 6, are again recognisable. The support construction 7 supporting the cable rollers 9 essentially consists of a [fastening support 17], which is mounted at the base frame 4 by way of resilient isolating elements 18, with a lefthand bearing support 20 and two cable roller supports. The cable roller support, which is arranged on the right and not illustrated here, corresponds with the cable roller supports according to Fig. 1. The lefthand cable roller support 21, which is shown here and constructed as a pivot lever, is fastened to a torsion rod 22 and rotatably mounted by way of this in the bearing support 20 connected with the fastening support 17. An abutment 23 prevents overloads of the torsion rod 22. This is prolonged rearwardly beyond the bearing support 20 (into the plane of the drawing) and connected at its rearward end with the fastening support 17 to be secure against relative rotation. The cable roller load 14 resulting from the cable tension forces of the support cable produces, by way of the cable roller support 21 constructed as a pivot lever, of the load carrying means 1 is produced as an input for an elevator control. Obviously usual commercial torque measuring apparatus based on different measurement principles can also be used as torque sensor. Patent Claims 1. Load carrying means (1) for cable elevators with integrated load measuring equipment, in which the weight force of the load carrying means (1) and useful load causes load-proportional deformation of at least one resilient element (7.1, 16, 22), wherein at least one sensor (15, 16) detects this deformation and produces, as an input for an elevator control, a signal representing the strength of the deformation and thus the load, characterised in that the load carrying means (1) is guided at vertical guide rails (2) and suspended at support cables (10), which are arranged in the form of a cable underslinging, i.e. are guided through under the load carrying means (1) and support, raise and lower this by way of two cable rollers (9) mounted below the load carrying means (1), wherein at least one of these cable rollers (9) is fastened to the load carrying means (1) by means of a support construction (7) containing the resilient element (7.1, 16, 22) and wherein the load-dependent cable forces (14) act on this resilient element by way of one or both of the cable rollers (9) and deform this element. 2. Load carrying means for cable elevators with integrated load measuring equipment according to claim 1, characterised in that the resilient element (7.1, 16, 22) can be a bending girder (7.1), a tension/compression rod (16). a torsion rod (22) or a compression spring. 3. Load carrying means for cable elevators with integrated load measuring equipment according to claim 1 or claim 2, characterised in that the sensor detecting the deformation of the resilient element (7.1, 16, 22) can be a strain gauge sensor, a piezoelectric or capacitive pressure sensor or tension sensor, a vibrating string pressure, tension or travel sensor, an opto-electrical distance or angle sensor, an inductive distance sensor or a capacitive distance sensor. 4. Load carrying means for cable elevators with integrated load measuring equipment according to any one of claims 1 to 3, characterised in that the bearing loads, which result substantially from the cable forces, of the two cable rollers (9) act on the resilient element (7.1,16,22). 5. Load carrying means for cable elevators with integrated load measuring equipment according to any one of claims 1 to 3, characterised in that the bearing load, which substantially results from the cable forces, of only one cable roller (9) acts on the resilient element (7.1, 16.22). 6. Load carrying means for cable elevators with integrated load measuring equipment according to claim 4 or claim 5, characterised in that the support construction (7) supporting the cable rollers is fastened to a carrier frame (car frame) of the load carrying means. 7. Load carrying means for cable elevators with integrated load measuring equipment according to claim 4 or claim 5, characterised in that the support construction (7) supporting the cable rollers is fastened to the base of the load carrying means, which, in this case, is self-supporting. 8. Load carrying means for cable elevators with integrated load measuring equipment according to claim 4 or claim 5, characterised in that the connection between the support construction (7), which supports the cable rollers (9), and the carrier frame or the base of the load receiving means is effected by way of resilient vibration-isolating elements (8). 9. A load carrying means for cable elevators substantially as herein described with reference to the accompanying drawings.

Documents:

in-pct-2002-1769-che-abstract.pdf

in-pct-2002-1769-che-claims filed.pdf

in-pct-2002-1769-che-claims grand.pdf

in-pct-2002-1769-che-correspondnece-others.pdf

in-pct-2002-1769-che-correspondnece-po.pdf

in-pct-2002-1769-che-description(complete) filed.pdf

in-pct-2002-1769-che-description(complete) grand.pdf

in-pct-2002-1769-che-drawings.pdf

in-pct-2002-1769-che-form 1.pdf

in-pct-2002-1769-che-form 18.pdf

in-pct-2002-1769-che-form 26.pdf

in-pct-2002-1769-che-form 3.pdf

in-pct-2002-1769-che-form 5.pdf

in-pct-2002-1769-che-other documents.pdf

in-pct-2002-1769-che-pct.pdf