RU217635U1 - Bracket for fastening boxes for low-voltage complete devices on vertical surfaces - Google Patents

Abstract

The utility model relates to construction. The bracket for fixing the boxes contains a body in the form of a plate made of a polymeric material, monolithic flat and elongated in height. In the upper part of the plate along its side edges there are protrusions stretched along the height of the plate, in which slots are made for pulling a bandage tape located over the front surface of the plate, and holes for the bolt. On the side walls of the plate, along the protrusions with slots, support pads are made with a thickness less than the thickness of the plate and the back surface of which lies in the plane of the back surface of the plate and which are conjugated with the front surface of the plate by arcuately concave bridges. In the lower part, a horizontally located protrusion is formed on the plate, under which three holes are made in the plate, two of which are located along the side edge of the plate. Each hole is made elongated, and the direction of the axis along the length of one hole is made different from the direction of the axes along the length of each other hole. 7 ill.

Description

The utility model relates to construction, in particular to the means of fastening on vertically oriented surfaces of wiring boxes or hollow box-shaped shells for low-voltage complete devices (NKU).

Under the NKU within the framework of this utility model is understood a set of protective switching devices, control devices, measurement, signaling, protection, monitoring and registration of electrical parameters, mounted and electrically combined in a single design solution (for example, in a common box) for the purposes of receiving, receiving and transmitting electrical energy of alternating or direct current.

Under the means of fastening on a vertically oriented surface is meant a bracket that is attached to the back wall of the box for the NKU and can be fixed on the vertical surface of the wall or column, pole.

Known designs of brackets for hanging empty shells or attaching cables or wires to concrete columns or poles, which provide the ability to mount on a vertical surface only with self-tapping screws (anchor bolts) or only with a bandage tape or with the possibility of simultaneous fastening and a self-tapping screw (anchor bolt) ) and a bandage tape (RU 181941, H02G 7/05, published on 07/30/2017).

So, for example, an anchor bracket is known, made in the form of a profile body with a base equipped with means for fastening to an external support, and containing in the upper part a single-claw eye, made with the possibility of fastening a U-shaped metal cable with a thermoplastic thimble put on at the bend , and along the edges of the base of the profile body, pairs of fixing protrusions are symmetrically located on its outer side, made with the possibility of fixing the position of the mounting tape, designed to prevent vertical displacement of the anchor bracket along the external support, while in the base as means for securing to the external support, three holes are made for threaded studs or for bolts (RU 168353, H02G 7/05, publ. 01/30/2017).

These brackets belong to the category of power mounts, as they are designed to hold in a taut position the cables or wires laid between the poles. Such brackets are designed for separation from the supporting surface by a tension that is perpendicular or transverse to the supporting surface. These brackets always have a transverse element such as an eyelet or hook, to which a thermoplastic thimble is attached, and to the latter a loop of cable or cable. In these brackets, an anchor bolt is used to position the bracket at a predetermined level on the surface, and the tearing force is perceived by one or two bandage tapes pressing the bracket to the supporting surface. In this regard, the design of the bracket is made of power, that is, made of metal and with elements of abutment against the supporting surface (as a rule, these are side parts bent to the back side). Such brackets are unsuitable for attaching cases such as boxes with electrical wiring or with elements of low-current systems, since they do not carry supporting parts for adhering to the flat wall of the box or a hollow shell that functions as an electrical panel.

The bracket protected by RU 122210, H02G 7/05, publ. November 20, 2012

This bracket contains a U-shaped eye for anchor fastening, the ends of which are welded to the front wall of a galvanized steel plate, having a U-shape and made on the front wall with a hole for the bolt and elongated slots from the side walls for pulling a mounting (shroud) through them. ) tapes.

This bracket was chosen as a prototype in terms of coincidence in terms of the presence of a base, slots for a bandage tape and a hole for a bolt.

This bracket is also used for supporting clamps for cable networks and wires that are hooked. The bracket works for separation under the action of a force whose vector coincides with the direction of the wires.

The disadvantage of this bracket is that the base is made in the form of a U-shaped curved plate, the side parts of which are used as stops in the supporting surface of the wall or pillar. When tightened with a bolt, the front wall is loaded, leading to deflection of the front wall. But the bolt does not hold the plate, it simply positions it on the surface. And when the bandage tape is tightened, the side walls are pressed against the surface, at which the side walls of the plate begin to diverge slightly to the sides.

Bandage tape - a stainless steel product in the form of a strip, clip or piece of a certain width and thickness. For production, sheet steel is used, which provides excellent fixation of any object to any structure. This is because it is made from special alloys. They give it high tensile strength parameters. And the U-shaped plate is made of black steel (galvanized), which has less strength, but greater ductility.

The tightening of the plate on the post is considered to be completed when an equilibrium is established between the stresses in the bandage tape and in the plate. This condition is evaluated by sensations, when it becomes difficult to stretch the tape with a special tightening mechanism. During operation, the stresses in the black steel are weakened, which cause the side walls to diverge or deform more, which leads to a weakening of the fastening as a whole; column. This is due to the fact that the supporting surface of the bracket has a linear character (along the abutment lines of the side walls).

In addition, this bracket cannot be used for mounting on vertical surfaces of cases such as boxes with electrical wiring or with elements of low-voltage systems or an electrical panel in the form of a hollow shell. This is due to the fact that there are no elements of attachment of the body or shell, places of their contact with the plate and insufficient area of support on the supporting wall or column.

The objective of the utility model is to create a support bracket that allows you to fix on vertical surfaces and pillars of housings for low-voltage switchgear using a bandage tape and / or an anchor bolt.

This utility model is aimed at achieving a technical result, which consists in increasing the reliability of attaching housings to a vertical surface by forming a supporting surface over the entire area of the bracket and extending the lugs with slots for the bandage tape over the housing to press the bolt head.

The specified technical result is achieved by the fact that in the bracket for fixing boxes for low-voltage complete devices on vertical surfaces, containing a body in the form of a plate in which two slots are made, spaced at the same level from each other for pulling the bandage tape and between which in the body of the plate is made hole for the bolt, the plate is made of a polymeric material, monolithic flat and elongated in height, in the upper part of the plate along its side edges there are protrusions stretched along the height of the plate, in which slots are made for pulling a bandage tape located over the front surface of the plate and a hole for the bolt, on the side walls of the plate, along the protrusions with slots, support pads are made with a thickness less than the thickness of the plate and the back surface of which lies in the plane of the back surface of the plate and which are conjugated with the front surface of the plate by arcuately concave bridges, and in the lower part of the plate a horizontally located protrusion is formed, under which in the plate has three holes, two of which are located along the side edge of the plate, each hole is made oblong, and the direction of the axis of one hole along its length is made different from the direction of the axes along the length of each other hole.

These features are essential and are interconnected with the formation of a stable set of essential features sufficient to obtain the desired technical result.

This utility model is illustrated by a specific example of execution, which, however, is not the only possible one, but clearly demonstrates the possibility of achieving the required technical result.

In FIG. 1 - shows a general view of the bracket in the perspective of ¾, side view;

fig. 2 - shows a top view of the bracket;

fig. 3 - holes in the lower part of the bracket plate are shown;

fig. 4 - fastening the bracket to the supporting surface on self-tapping screws;

fig. 5 - fastening the bracket to the supporting surface on the bandage tape;

fig. 6 - general view of the box for the components of the NKU;

fig. 7 is a view of the rear wall of the box according to FIG. 6.

According to this utility model, the design of a bracket for fixing boxes for low-voltage complete devices on vertical wall surfaces and on poles is considered. Boxes or cases for NKU are lightweight equipment, as they are produced either from thin-walled steel (painted) or plastic. This is explained by the fact that the NKU is a set of switching devices together with controls, protection, settings, measuring instruments, signaling mechanisms, etc., which are lightweight in themselves. When hanging on a vertical surface, the load on the bracket acts in the direction of gravity and is equal to the weight of such a complete box. Therefore, only the shear load (bearing load on the shear) acts on the fasteners of the bracket. But bolted fasteners that are not fixed by a nut and washers from spontaneous rotation have a drawback, which lies in the fact that after tightening the bolt begins to turn out during operation or time. This is explained by the fact that the forces on the helical thread line are decomposed along the coordinate axes into the axial force on the screw and into the driving circumferential force, which leads to the return rotation of the bolt. To increase the reliability of fastening, a bandage tape is used that presses the bracket plate to the supporting surface.

Within the framework of this utility model, a bracket made entirely of polymeric material is considered. The bracket contains a body in the form of a plate 1, made monolithic flat (on the back side and on the front side) and elongated in height. In fact, the shape of the plate in plan is a rectangle of a given thickness. The use of a polymeric material made it possible to ensure a snug fit of the plate to the vertical support surface over a sufficiently large area. At the same time, if we take into account that the concrete surface of the wall or pillar has a high roughness, and the strength of the polymer material is inferior to concrete, then when tightened with a bolt (self-tapping screw) or bandage tape, the polymer plate settles on the protrusions of irregularities and takes them into its body. This leads to increased friction between these materials and increases the bearing capacity of the bracket.

In the upper part of the plate in its central zone, a hole 2 is made for screw fasteners (bolt, anchor bolt, self-tapping screw), which allows the plate to be fixed on the supporting surface 3 of a vertical wall (Fig. 4) without the use of a bandage tape 5 in the case of a lightweight version of the box with electrical filling NKU inside.

And to use the bandage tape 5 as a fastener, for example, when installing a box under the low-voltage switchgear on a pole 6 or rack, two slots are made in the body of the plate 1, 7 spaced at the same level from each other for pulling the bandage tape. In the upper part of the plate along its side edges there are protrusions 8 extended along the height of the plate, in which slots 7 are made for pulling the bandage tape. And hole 2 for screw fasteners is located between these protrusions 8. In this case, when fixing, the tape is located over the front surface of the plate and over the hole for screw fasteners. If there is a bolt in the hole, the tape covers the head of the bolt and prevents the bolt from untwisting.

A feature of the use of a bandage tape is that it exerts compressive and deforming pressure on the edges of the transition of the front wall of the bracket into the side walls. To prevent this deformation on the side walls of the plate along the protrusions with slots, support pads 9 are made with a thickness less than the thickness of the plate and the back surface of which lies in the plane of the back surface of the plate. These support pads are smoothly mated with the front surface of the plate by arcuately concave bridges 10 or ledges. When tightening the bandage tape, its strip smoothly goes around the edges along the jumpers (protrusions), distributing the load at the bend of the tape between the body of the plate itself and the supporting platforms.

In the lower part, a horizontally located protrusion 11 is formed on the plate, under which three holes 12 are made in the plate, two of which are located along the side edge of the plate, each hole is made oblong, and the direction of the axis along the length of one hole is made different from the direction of the axes along the length every other hole. These holes are used to attach the bracket to the back wall of the box or hollow shell that carries the components of the ASSEMBLY. Making the holes oblong and with different orientations of their long axes allows you to avoid the need for precise alignment of the attachment points on the box and expand the range of boxes.

The horizontally located protrusion has two functions. The first one is the support element for the upper edge of the box in order to position it on the bracket as a position limiter. The second one is a support element for the back wall of the box under the low-voltage switchgear in those cases when the back wall is recessed in relation to the side walls (depending on the design scheme of the box).

In FIG. 4 shows an example of fixing the bracket only by means of an anchor bolt, and in FIG. 5 - fixing the bracket with a bandage tape. The example of FIG. 5 also applies to the case where the bracket plate is fastened with both a bolt and a bandage band.

Since the boxes can be of various designs and have a different layout of the NKU components inside, the bracket design provides for a cutout in the lower part in the area of the holes either on one side or on the other side (left-hand or right-hand). Accordingly, two holes located along the side edge of the plate are located on the side opposite the cutout.

In FIG. 6 shows an example of a box with a parallelepiped shape for the components of the low-voltage switchgear. As seen in FIG. 7, at the corners of the box there are supporting corner ledges 13, which ensure the preservation of the shape and strength of the thin-walled box made of polymeric material. These protrusions are used as elements for positioning the box relative to the protrusion 11 on the plate. And in the corner areas under the corner ledges, three round holes 14 are made, which are used to attach the bracket to the rear wall of the box.

The utility model is industrially applicable, can be manufactured using casting or molding technologies for polymer raw materials, and during testing showed a high degree of retention on vertical surfaces of various roughness. In this case, the load from the use of the bandage tape is distributed on the body of the plate, and the slots in the protrusions for this tape perform a non-force function of the band position limiters. The tests were carried out for lightweight boxes and shells for the components of the low-voltage switchgear and do not apply to heavy-weight versions of the equipment for the low-voltage switchgear.

Claims (1)

Bracket for fixing boxes for low-voltage complete devices on vertical surfaces, containing a body in the form of a plate, in which two slots are made, spaced at the same level from each other for pulling a bandage tape and between which a hole for screw fasteners is made in the body of the plate, characterized in that that the plate is made of a polymeric material, monolithic, flat and elongated in height, in the upper part of the plate along its side edges there are protrusions stretched along the height of the plate, in which there are slots for pulling a bandage tape located over the front surface of the plate, and holes for screw fasteners, on on the side walls of the plate along the protrusions with slots, support pads are made with a thickness less than the thickness of the plate and the back surface of which lies in the plane of the back surface of the plate and which are conjugated with the front surface of the plate by arcuately concave bridges, and in the lower part of the plate a horizontally located protrusion is formed, under which in the plate three holes are made, two of which are located along the side edge of the plate, each hole is made oblong, and the direction of the axis of one hole along its length is made different from the direction of the axes along the length of each other hole.

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