RU2627860C2 - Sensor for measuring tie strength - Google Patents

Abstract

FIELD: measuring equipment.

SUBSTANCE: device consists of a metal case in the form of a parallelepiped with a mechanical design for an extensometer, from which support and fixing elements are provided on one side or on both sides, equipped with grooves along the perimeter. As support elements, three pins or rigid pins located at the tetraktis nodes with respect to the longitudinal axis of the case are used, one of them occupying the extreme position is movable and is extended by shifting forward and backward to return to its working position from the front. On the back surface of the case is a separate surface area, limited by pits, under the hook with a wrench, adjustable or not, with which alignment can be performed. In addition, a protective cover is provided, which is put on and attached to the sensor case by pressing.

EFFECT: improving the measurement accuracy.

4 cl, 17 dwg

Description

FIELD OF THE INVENTION

This invention can be applied in the field of production of measuring instruments intended, in particular, for measuring the tension of cables.

BACKGROUND OF THE INVENTION

The currently used sensors have a problem in the form of non-separable housings, to which cables are biased, the tension of which must be measured or checked. Due to the tendency of the cables to return to their natural position, which was previously violated in order to place them near the sensor, the latter should be moved to the point where the cables are closest to each other.

Therefore, it would be necessary that the sensor is located on each cable, thus avoiding its forced shift when it is necessary to bring the cables closer to each other.

As for the current state, several documents are known that describe similar sensors designed to measure cable tension, among which the most relevant patents are US 3653258 A; DE 19605036 A1; US 4118978 A; GB 2063494 A. However, none of them, either one at a time or together, can be considered equivalent to the sensor proposed here, as set forth in the claims.

OBJECT OF THE INVENTION

As set forth in the title of the text of the present description, the present invention relates to a sensor for measuring cable tension. In particular, the sensor housing is rotated, which was improved to measure the cable tension, which allows the operator to determine the weight of the mass suspended from them and to limit cargo levels during lifting operations with masses suspended on the cables, which is important for lifting blocks or a lifting mechanism, such as an elevator for which the introduction of this device is of most interest.

DESCRIPTION OF THE INVENTION

Thus, the improved sensor for measuring the cable tension of the present invention is an obvious innovation within its defined range of applicability, making it possible, on the one hand, to create a sensor that is small enough so that one cable can be placed on each cable, even if such cables They are located close enough to each other, and on the other hand, reduce the cost of installation due to the simplicity of the sensor itself.

Another advantage of the present invention is the low time required to install the sensor, which allows you to install a large number of sensors for a sufficiently short period, which also reduces installation costs.

At the same time, the present invention, as can be understood from the design of the sensor when it is installed on each cable, allows you to compare the difference in the loads on the cables and even makes it possible to detect sagging dangling cables, as well as automatically interrupt work to ensure safety.

The sensor can be equipped with built-in electronics in the form of an LED for intermittent signals in case of sagging cables.

Proposed in the present invention, the sensor for measuring cable tension consists of a box in the form of a parallelepiped, from which various supporting structures extend, with a mechanism inside that allows you to determine areas sensitive to mechanical stress, where extensometers are installed that change their electrical resistance whenever the site experiences mechanical stress in the aforementioned zone sensitive to it, which makes it possible to determine the deforming forces acting on the material that are not divergence measure.

In particular, in accordance with a preferred embodiment of the present invention, the aforementioned sensor housing includes three pins or trunnions that form the reference points of the cable to which the sensor is attached, these trunnions are mounted on one side of the sensor and are located along it, projecting at right angles to the plane formed by the side from which they protrude in positions corresponding to the tetraktis nodes relative to the longitudinal axis of the body. In addition, a groove is made in the loose end of the trunnion through which the tensioned cable must pass.

As a result of the load in the cable, tension of a different magnitude arises, which acts on the trunnions and transfers the deformation to the sensor housing, driving an extensometer, which generates an appropriate electrical signal, the reading of which allows you to evaluate the load intensity. On the other hand, for the convenience of mounting the sensor, as well as to eliminate the need to use a special tool and to secure the sensor with a public tool, such as a wrench, adjustable or not, an appropriate size, the proposed sensor has the following additional features.

On the one hand, two of these three trunnions designed to fix the cable with the appropriate grooves are fixed motionless relative to the sensor housing, while the third is movable, extends relative to the sensor housing; that is, the operator extends either forward or backward so as to “disappear” when necessary when the sensor is mounted on the cable, which facilitates the assembly operation, while it may “appear” again when the cable is already placed in the grooves of both fixed trunnions or protrusions and the housing the sensor is slightly rotated relative to the cable so that the latter does not violate the position through which the movable trunnion or protrusion passes.

At the same time, on the back surface there is a protrusion and a separate surface section, bounded both above and below by pits, the thickness of which is less than the thickness of the rest of the housing, while the size and configuration of this surface section provide engagement of a conventional wrench of the appropriate type, with which the operator must appropriate actions during assembly in order to align and move the sensor housing to the correct position so that the third trunnion (or protrusion) can extend I am in its operating position.

It is easy to understand how both features greatly simplify operating conditions and the time taken to install the sensor on the cable, the tension of which will be measured.

Finally, a protective case is provided that gives the sensor a more aesthetic appearance.

DESCRIPTION OF DRAWINGS

For a better understanding of the present invention, drawings are attached to the description.

The figure 1 presents a side view with a partial section of a sensor for measuring tension, which is the aim of the present invention.

The figure 2 presents a top view of the sensor depicted in figure 1.

The figure 3 presents a view of one of the small sides of the sensor depicted in the previous figures.

In figures 4a, 4b, 4c and 4d presents views of the proposed sensor from different sides.

Figures 5a-5j show a sensor during assembly.

DESCRIPTION OF PREFERRED EMBODIMENTS FOR CARRYING OUT THE INVENTION

Based on the above figures and according to the accepted numbering of positions, we can evaluate an example implementation of a sensor for measuring cable tension, which is the purpose of the present invention, the various parts and elements of which are presented and described in detail below.

Thus, as can be seen in figures 1-3, the sensor under consideration consists of a housing in the form of a parallelepiped made of metal (1), from which the supporting elements (2, 2 ') depart, ensuring its installation on the cable (3), while the housing zone (1), sensitive to mechanical stresses, is mounted a mechanical structure (4), in which extensometers (not shown) are placed, which change their electrical resistance when the section of the housing (1) where the aforementioned mechanical structure (4) is located, experiences mechanically voltage. Thus, we can determine the deformation force of the material.

According to a preferred embodiment of the present invention, three pins or rigid trunnions are used as the aforementioned support elements (2, 2 '), although it is obvious that there could be more pins, while they protrude from the side of one of the walls of the housing, made in the form parallelepiped (1), while they can also exit from the opposite side to allow the sensor to be mounted on two cables, or even such rigid trunnions could extend to another similar sensor so that the tension measurement is possibly on an arbitrary number of ranked cables placed between the two sensors.

In any case, such support elements (2, 2 ’) in the form of pins protrude at right angles to the plane of the aforementioned wall of the sensor housing (1) in predetermined positions along such a wall on both sides of the longitudinal axis of the sensor.

According to this invention, for mounting the sensor on a pair of closely spaced cables, the supporting elements (2, 2 ’) can be made in different sizes, with both cables placed on one side of the sensor.

The supporting elements (2, 2 ’) to a minimum extent change the direction of the cable, forcing it to take a V-shape, with a defining angle, tending to open with increasing mechanical stress, which causes the sensor to deform at the location of the strain-sensitive mechanical structure (4).

To ensure proper connection of the sensor with the cables, the supporting elements (2, 2 ’) are provided with grooves that play the role of guides.

To simplify installation, two support elements are fixedly mounted (2) to the sensor housing (1), while the third is movable (2 '), and in one embodiment of the present invention it is put into place during installation using the hole ; or in another alternative, he is put forward, which will be explained below.

The guide grooves ensure that the third support element (2 ') cannot move from its position, since the remaining support elements (2) together with the cable (3) determine the position of the unique third support element on the plane parallel to the wall of the box in the form of a parallelepiped (1) ), in which all the supporting elements (2, 2 ') are placed.

In order to keep the sensor on the cable, the minimum mechanical tension, which is always present in elevators, etc., is necessary.

Inside the housing (2) of the sensor (1), electronics are integrated that provide signal amplification, or even a microprocessor that provides the connection of several sensors via the bus.

Figures 4a and 4d show an exemplary embodiment of the present invention in which one of the support elements or the extreme journal, position (2 ’), is movable; that is, this element can be moved back and forth relative to the sensor housing (1) in order to simplify the assembly of the sensor, as described above.

Thus, in FIG. 4a, the movable support element (2 ’) is shown forward shifted; that is, in a position corresponding to the position of the stationary support elements (2), while in figure 4b it is shifted backward, protruding relative to the rear of the housing (1).

In general, a mechanical structure (4) is inserted into the housing (1) for an extensometer, which provides the generation of electrical signals and their transmission to the control device via an electric wire (5). In addition, figure 4d shows that the mechanical cable 3 passes between the supporting elements (2, 2 ’) in the same way as in existing sensors.

Figure 4c shows a section through the rear side of the housing (1) with a portion of the insulated surface (6) as a result of creating two grooves (7a, 7b) on the surface that define the upper and lower limits. Operations in this area are performed using any appropriate conventional wrench, adjustable or not, which can provide a turn to overcome the resistance caused by the cable tension (3) during assembly and connection of the sensor.

Figures 5a-5j show a process for assembling a sensor of the present invention on a cable whose tension needs to be measured.

Figure 5a shows a front view of the sensor housing (1) with fixed support elements (2) and with a movable support element (2 ’) below.

Figure 5b shows a sensor with a cable (3), which is already between the supporting elements (2, 2 ’), and with a wrench 8 used during assembly, protruding from the rear side of the housing (1).

Figure 5c shows a side view of the sensor housing (1) with the movable support element (2 ') shifted back, which makes it easy and convenient to place the sensor with a cable (3) passing between two stationary support elements (2) using a small tilt the sensor housing (1) as shown in figure 5d of this sequence.

5e shows a sensor housing (1) with a wrench (8) acting on a surface portion (6) from the rear of the housing.

In figure 5f, the movable support element (2 ') is shown in the working position with a forward shift, while the cable (3) is placed in the groove with a wrench (8), which rotates the sensor housing (1), overcoming the cable tension (3), to place it in a position in which the movable support element (2 ') can receive the cable, which is perhaps more clearly shown in figure 5g.

According to a preferred embodiment of the present invention, after connecting the cable to the three support elements (2, 2 ’), the assembly is completed by installing a protective cover (9), which is attached to the body (1) by pressure, as can be seen in figures 5h, 5i and 5j. We do not consider it necessary to continue this description, as specialists are able to understand the scope and advantages of the present invention.

Notwithstanding the foregoing, it should be understood that the invention has been described using a preferred embodiment, and it will be understood by those skilled in the art that these and other embodiments of the invention are possible within its spirit and scope.

Claims (4)

1. A sensor for measuring the tension of cables, which includes an elongated metal body in the form of a parallelepiped (1) with supporting and fixing elements of the cable (2, 2 '), equipped with grooves around the perimeter to fix the cable (3) in place, while the surface of the housing (1) is a mechanical structure (4), in which an extensometer is placed that generates signals corresponding to the load levels on the cable (3) on which it is mounted, such support elements (2, 2 ') protrude from at least one of sides of the housing (1), distributed on and the surfaces of this side come out at right angles to the surface of the side from which they appear, characterized in that one (2 ') of the support elements, in the extreme position, is movable, extends [retracts] when moving forward and backward in this way, which can be taken inward when shifted back at the first stage of the sensor assembly on the cable (3) and then moved forward again to the working position when the sensor housing (1) moves to the corresponding position in response to bending resistance due to mechanical tension caused by heating viscous this cable (3); and the fact that a separate surface area (6) is defined on the rear surface of the housing (1), bounded by pits (7a, 7b) above and below, while the size and configuration of this surface area ensure engagement of a tool, such as a wrench (8), adjustable or not, with which it is possible to perform alignment by turning the housing (1) of the sensor, for installing the cable (3) in the supporting elements: both in fixed (2) and in movable (2 '). 2. A sensor for measuring the tension of cables according to claim 1, characterized in that three rigid pins in the form of pins that protrude from one side of the housing (1) and are placed in the tetraktis nodes with respect to support elements (2, 2 ') are used the longitudinal axis of this housing. 3. A sensor for measuring cable tension according to claim 1 or 2, characterized in that the supporting elements (2, 2 ’) have different sizes. 4. A sensor for measuring cable tension according to claim 1 or 2, characterized by the presence of a protective casing (9), which is put on and fastened to the sensor housing (1) by pressure.

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