US20090175678A1

US20090175678A1 - Device Support

Info

Publication number: US20090175678A1
Application number: US12/223,087
Authority: US
Inventors: Klaus Nientiedt; Albert Luetke Zutelgte
Original assignee: BSW ANLAGENBAU GmbH
Current assignee: BSW ANLAGENBAU GmbH
Priority date: 2006-01-23
Filing date: 2007-01-23
Publication date: 2009-07-09
Also published as: ATE522963T1; WO2007082962A2; DE102006003349A1; WO2007082962A3; EP1977487B1; EP1977487A2

Abstract

A device support comprises a cabinet frame that is formed by metal hollow profiles (11) and that has at least in one of its corners a parallelepiped corner connector element (30) connected to at least one of the hollow profiles (11) by means of a screw. At least one outside face of the corner connector element (30) is configured as a securing face which has a guiding shoulder (34) with at least two parallel outer edges (34.1), resting on inner peripheral surfaces of the hollow profile (11). The hollow profiles (11) have a closed cross-section. A throughbore runs from every securing face for receiving the screw shank and continues, starting from a support shoulder in the interior of the corner connection element (30), along a passage recess (32) which extends to an outside face of the corner connector element opposite the securing face.

Description

BACKGROUND OF THE INVENTION

The present invention relates to a device support that includes a cuboidal cabinet frame formed by a metal hollow profile, which exhibits at least at one of its corners a cuboidal corner connector element that is connected to at least one of the hollow profiles via a screw connection, whereby at least one outer side of the corner connector element is designed as an attachment side that exhibits at least one guiding shoulder with at least two parallel outer edges that rest on inner perimetral surfaces of the hollow profile.
Such a cabinet frame for a device support is known from the International Patent Application No. PCT/WO94/14307. The connection of corner connector elements and hollow profiles via screws allows for a modular design and requires significantly less storage and handling space when compared to welding structures that cannot be disassembled. However, the profiles are designed as open profiles that have relatively low torsion stiffness. Screw connections are formed by threaded holes in the corner connector elements and screws that are screwed into the corner connector element from within the profile. To make the screw heads accessible, the profiles are even disengaged at an angle at two adjacent areas, which severely lowers the bending and torsion stiffness. Still, access to the screw heads is difficult because an assembly tool for screws and nuts can be employed with limited space only. Hollow profiles that have been painted prior to assembly must be connected via grounding straps to achieve an equalization of the electrical potential.

SUMMARY OF THE INVENTION

It is, therefore, the objective of the present invention to improve a device support with a cabinet frame of the type described above, such that a simpler and faster assembly as well as a greater stiffness can be achieved.
This objective, as well as further objectives which will become apparent from the discussion that follows, is achieved, in accordance with the invention, by a device support which comprises a cabinet frame that is formed by metal hollow profiles and that has at least in one of its corners a parallelepiped corner connector element connected to at least one of the hollow profiles by means of a screw. At least one outside face of the corner connector element is configured as a securing face which has a guiding shoulder with at least two parallel outer edges, resting on inner peripheral surfaces of the hollow profile. The hollow profiles have a closed cross-section. A throughbore runs from every securing face for receiving the screw shank and continues, starting from a support shoulder in the interior of the corner connection element, along a passage recess which extends to an outside face of the corner connector element opposite the securing face. The screw connection comprises a screw to be aligned in the longitudinal direction of the hollow profile and a receiving element with a threaded port in the interior of the hollow profile. The screw is held in the passage recess by the screw head and the screw shank extends into the interior of the hollow profile up to the receiving element.
In this way, forces acting perpendicular to the respective profile axis are assumed by the guiding sections such that the screw connections are not encumbered by shear stress.
Good access of the screws is provided by leading the screws from the outside through the corner connector element into the hollow profile. Significant advantages for storage and handling are provided by the ability of a simple and fast assembly and disassembly. The desired cabinets can be assembled from the pre-painted profiles “on demand”, and that either at the manufacturer or on site by the customer. This increases the flexibility and reduces the reaction times. At the same time, storage and/or handling times are reduced as well since it is not necessary to store fully assembled cabinets; instead, it is sufficient to store the painted profiles. Furthermore, it is not necessary to handle and ship fully assembled cabinets; instead, components can be shipped as significantly smaller packages and can be assembled on site to a finished device support with great stiffness quickly and without problems.
In one particularly advantageous embodiment, the corner connector elements of the invention consist of cuboidal, in particular of cube-shaped elements that feature a feed-through cutout for the screws in at least one spatial axis. In a particularly advantageous embodiment, these feed-through cutouts are found in all three spatial axes. Preferably, the cutouts are designed such that they exhibit a smaller diameter on the attachment side that faces the hollow profile, than on the side that is facing away from the respective profile. In this case, the transition serves as a support for the screw head allowing for the introduction of great pre-loads into the receptacle for the fastening devices.
In the case of two attachment sides oriented at a right angle to each other and at least two intersecting feed-through cutouts, it is particularly advantageous from the point of view of a simple assembly if the depth of at least one of the feed-through cutouts between the respective support shoulder and the envelope curve of the intersecting feed-through cutouts corresponds at least to the height of the screw head. This means that if one or two screws are already in place, it is possible to insert another screw freely into the corner connector element, and to tighten it using an also insertable tool such as an allen wrench, for example. It is not necessary to follow a particular assembly sequence as long as no oversized screw heads are used.
Such an oversized screw head is designed such that fills the feed-through cutout in the corner connector element entirely with regard to length and diameter and that it exhibits an inner cutout that is at the side facing the screw shaft designed as an internal drive, for example as a hexagonal socket or with internal serrations, and above it is, at least in part, provided with an internal female thread. This not only establishes the connection to the hollow profile but it is additionally possible to screw in eyelets, hooks or adjustable feet. In this manner, a respectively designed device support can be readied for crane lifting, for example. The occurring tensile forces are introduced directly into the perpendicularly arranged profiles of the cuboidal cabinet frame and thus, cause only tensile loads on the screws. When installing adjustable feet at the bottom side, the weight forces are diverted directly into the feet via the vertical hollow profiles without causing bending stress on the lower, perpendicular oriented hollow profiles.
Preferably, the separately insertable support element has at its surface that faces the corner connector element a serrated profile and/or the edge of the insert cutout adjacent to the corner connector element is at least partially serrated. By this, a paint coating on the hollow profile and its edges in the area of the insert cutout are penetrated when the screw connection is tightened, thus pressing the support element onto the edge. Thicker, brittle protective coatings such as powder paint coatings or anodized coatings chip partially due to the serrated profile such that an electrically conducting contact is established. Even if the edges of the hollow profile on the face side that rest on the corner connector elements are provided with an electrically isolating coating, a short circuit will still be established with the corner connector elements via the screws that engage in the threaded holes and that remain preferably blank. It is, therefore, no longer necessary to connect the individual hollow profiles using grounding straps. Thus, the profiles used for the cabinet frame subject to the invention can be painted prior to assembly. It is no longer necessary to paint the entire assembled cabinet frame; instead, only the individual profiles need to be painted. Painting systems can be dimensioned much smaller leading to significant cost savings in manufacturing.
In one preferred embodiment, it is provided that the corner connector elements are each connected with at least three profiles which point into respective other dimensions of the space, in this manner forming a three-dimensional device support, which will subsequently be designated as a device cabinet.
In one preferred embodiment of the device cabinet subject to the invention it is provided that corner connector elements are arranged at each of the four upper corners of the cuboidal cabinet frame that are each connected to three profiles via screw connections, while in the lower section of the cuboidal cabinet frame, a rectangular base frame is provided, where its four corners are each connected with a vertically arranged profile of the cuboidal cabinet frame via weld or screw connections. Such a device cabinet exhibits particularly great stability because its base frame can be built particularly heavy and robust.
In one particularly preferred embodiment of the device cabinet subject to the invention, it is provided that corner connector elements are arranged at all eight corners of the cuboidal cabinet frame that are each connected to three profiles via screw connections.
Preferably, the receiving elements for the screws located on the inside of the profiles are designed such that pre-loads can be introduced into the receptacle during the screwing-in of the fastening devices. These receptacles consist of, for example, the rectangular perpendicular sheet metal located inside the profiles, each exhibiting a threaded borehole. The perpendicular sheet metal can be attached with their narrow-side ends at the interior walls of the profiles, for example by welding. When screwing in the fastening devices, a pre-load is introduced into the perpendicular sheet metal, which pulls profiles stronger to the corner connector elements, thus leading to a significantly greater stiffness of the connection and of the entire device cabinet. The stiffness of device cabinets manufactured in this manner surpasses even that of welded cabinets.
Furthermore, the device cabinet designed according to the invention may also feature a covering plate suspended from the cabinet frame, whereby the covering plate is provided with at least one locking strap, the locking strap protrudes beyond a circumferential side edge of the covering plate and the locking strap rests on an outer surface of the profile of the cabinet frame. The exact design of this covering plate and of its suspension is known from the German Utility Model Patent No. DE 200 188 18, and the entire contents of this German Utility Model Patent is incorporated herein by reference.
For a full understanding of the present invention, reference should now be made to the following detailed description of the invention as illustrated in the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a first cuboidal cabinet frame for a device cabinet subject to the invention with corner connector elements at all eight corner.

FIG. 2 is a cabinet frame for a device cabinet subject to the invention with corner connector elements at the upper corners and a rectangular base frame in the lower section.

FIG. 3 b is a section through a corner connector element.

FIG. 4 a is an exploded view of a corner connection.

FIG. 4 b is the assembled corner connection of FIG. 4 b.

FIG. 5 is a sectional view of a first screw connection for a device cabinet subject to the invention.

FIG. 6 is an exploded view of a second screw connection for a device cabinet subject to the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The preferred embodiments of the present invention will now be described with reference to FIGS. 1-6 of the drawings. Identical elements in the various figures are designated with the same reference numerals.
FIG. 1 shows a first cabinet frame 10 for a device support with hollow profiles 11, 12, 13 subject to the invention as well as corner connector elements 30. The cabinet frame includes a total of eight corner connector elements 30 as well as twelve hollow profiles. The corner connector elements 30 are connected with the profiles via screw connections. Because a spatial structure is being formed, the device support will be called a device cabinet hereafter.
FIG. 2 shows a second cuboidal cabinet frame 20 with a rectangular base frame 24, where the four corners are each connected with a vertically arranged hollow profile 22 of the cuboidal cabinet frame 20 via a weld or screw connection. Corner connector elements 30 are arranged at the four upper corners of the cuboidal cabinet frame 20, with said corner connector elements being connected via screw connections to the vertical hollow profiles 22 and hollow profiles 21, 23, which form an upper frame of the cabinet frame.
The base frame 21 can be designed in its dimensioning such that it exhibits a great weight and/or a wide footprint and in this manner provides the cabinet frame 20 with great stability.
FIG. 3 a shows a perspective view of a corner connector element 30 for a cabinet frame for a device cabinet subject to the invention. Essentially, the corner connector element is a cube-shaped base body that exhibits a feed-through cutout 32 in each of its spatial axes extending from an outer side 31 into the inside. Furthermore, the corner connector element 30 exhibits at its attachment sides guide shoulders 34 that are adapted to the inner cross-section of the hollow profile of the cuboidal cabinet frame and that can be inserted in said frame.
FIG. 3 b shows a sectional view of the corner connector elements 30. From the attachment side 33, a cutout 33.1 for a screw shaft 58.2 leads to the support shoulder 33.2 for a screw head 58.1. The intersecting feed-through cutouts 32 form a central cavity 36. Because a depth T between the cavity 36 and the support shoulder 33.2 is greater than the height of the screw head 58.1, the feed-through cutouts of the respective other spatial axes remain always accessible, even if a screw 58 has already been placed into the feed-through cutout 32 of a spatial axis.
The outer side edges 34.1 at the support shoulder 34 are recessed corresponding to the wall thickness of the provided hollow profile versus the outer sides of the corner connector element 30, such that a continuous transition from the hollow profile to the corner connector element occurs.
FIG. 4 a shows an exploded view of the structure of a corner connection of the cabinet frame from FIG. 1 with the hollow profiles 11, 12, 13 each pointing into different spatial axes as well as the cube-shaped corner connector element 30 and the screw 58 that can be inserted through the feed-through cutouts 32 of the corner connector element. Arranged in the inside of the hollow profiles 11, 12 and 13 on the side facing the corner connector element 30 are receiving elements 55 or 51 with a female thread 57. FIG. 4 b shows the hollow profile 11, 12, 13 in the condition connected with the corner connector element 30. The exact structure of the screw connection between the corner connector elements and the profiles is presented in FIG. 5 in an exemplary fashion with a fixed installed receiving element 55 and in FIG. 6 with a receiving element 51 that can be inserted separately.
FIG. 5 shows in exemplary fashion the structure of a screw connection between a corner connector element 30 and a hollow profile 11. The corner connector element 30 exhibits feed-through cutouts 53 in all three spatial axes with only one of said cutouts being shown in FIG. 5 for graphic reasons. Furthermore, the corner connector element exhibits guide shoulders 34 that are adapted to the inner cross-section of the hollow profiles 11 and that can be inserted into them. A receiving element 55 is located in the inside of the profile 11 and consists of a longitudinal sheet that is welded together with two opposite insides of the profile 52 via weld seams 56 and exhibits a centrally located threaded hole 57. An attachment device 58 in the form of a screw is inserted through the feed-through cutout 32 of the corner connector element 30 and screwed into the thread 57. When tightening the screw 58, a pre-load is introduced into the longitudinal metal sheet 55, which is shown in FIG. 5 through the curved presentation of the longitudinal sheet 55, which is straight in its original condition. A close and stiff connection between the corner connector element 30 and the profile 11 can be established by introducing the pre-load. The connection is additionally supported through the outer edges 34.1 of the corner connector element 30, which are adapted to the inside diameter of the profile 52. In particular, the guide shoulders 34 assume shear forces that are directed orthogonally to the longitudinal direction of the screw connection and ensure in this manner that the screws experience only tensile stress.
For purposes of clarity, the distance between the corner connector element 54 and the insides of the profile 52 is exaggerated in FIG. 5. In actuality, the shoulders 34 are in contact with the insides of the profile 52 and thus contribute to the stabilization of the connection.
FIG. 6 shows an additional embodiment of a corner connection at a cabinet frame subject to the invention. In their end sections, the hollow profiles 11, 12, 13 each exhibit two cutouts 16 introduced at opposite sides, which can be inserted in a receiving element 51. For a clear presentation, the receiving elements 51 are shown directly adjacent to the corner connector element 30. The usage position of the receiving elements 51 in the hollow profiles is illustrated through the dot-dashed lines provided with arrows. In the usage position, the serrated edges 17 of the cutout 16 are located in the grooves 52 of the receiving element 51. When the screw connection is tightened, the base of the groove presses against the peaks of the edge 17. This leads to high local area pressures that lead to an intentional destruction of paint or protective coatings adhering to it and to an electrically conducting connection.
While the screw connection is established via regular hexagon socket screws 58 where the heads are received sunken so deep in the corner connector element 30 that the feed-through cutouts 32 remain free in all spatial axes, the connection with the vertical hollow profile 12 is established via a specially designed screw 59 with a head that is designed such that it fully fills the feed-through cutout with its outer circumference. A central cutout that exhibits in the lower section a hexagonal socket or internal serration drive and above it a threaded hole that allows for screwing in a hook or an eyebolt is present in the head.
There has thus been shown and described a novel device support which fulfills all the objects and advantages sought therefor. Many changes, modifications, variations and other uses and applications of the subject invention will, however, become apparent to those skilled in the art after considering this specification and the accompanying drawings which disclose the preferred embodiments thereof. All such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention, which is to be limited only by the claims which follow.

Claims

1. A device support, comprising a cabinet frame, which is formed from metal hollow profiles and which has at least at one of its corners a cuboidal corner connector element that is connected to at least one of the hollow profiles via a screw connection, wherein at least one outer side of the corner connector element is designed as an attachment side, having at least one guide shoulder with at least two parallel outer edges that rest on the inner perimetral surfaces of the hollow profile, the improvement wherein

the hollow profiles exhibit a closed cross-section,

a throughhole for receiving the screw shaft runs from every attachment side and continues, starting from the support shoulder, in the inside of the corner connector element in a feed-through cutout, extending to an outer side of the corner connector element located opposite the attachment side, and

the screw connection comprises at least one screw to be aligned in the longitudinal direction of the hollow profile and a receiving element with a threaded hole located in the interior of the hollow profile, whereby the screw is held in the feed-through cutout by its screw head, which exhibits an inside drive, and the screw shaft extends into the interior of the hollow profile to the receiving element.

2. A device support as defined in claim 1, wherein the corner connector element exhibits at least two attachment sides oriented at a right angle to each other and at least two intersecting feed-through cutouts, whereby the depth (T) of at least one of the feed-through cutouts between the respective support shoulder and the envelope curve of the intersecting feed-through cutouts corresponds at least to the height of the screw head.

3. A device support as defined in claim 2, wherein a screw exhibits a screw head that fills the feed-through cutout entirely and that exhibits an interior cutout that is formed as an inner drive at the side that is facing the screw shaft and above is provided at least in part with a female thread.

4. A device support as defined in claim 3, wherein the receiving element can be placed in two placement cutouts that are inserted in the hollow profile perpendicular to the longitudinal axis at opposite sides, whereby the receiving element comprises at its end sides at least two lay-on edges that are oriented mirror-inverted to each other.

5. A device support as defined in claim 4, wherein the edge of the placement cutouts adjacent to the corner connector element the area of the receiving element facing this edge is at least partially serrated.

6. A device support as defined in claim 4, wherein the receiving element exhibits a clamp-shaped configuration with two lay-on edges directed toward the inside.

7. A device support as defined in claim 4, wherein the receiving element exhibits a T-shaped configuration with two lay-on edges directed toward the outside.

8. A device support as defined in claim 4, wherein the receiving element exhibits two grooves with a width that corresponds to the wall thickness of the hollow profile.

9. A device support as defined in claim 1, wherein the receiving element is designed as a plate element that is welded to the inside of the hollow profile.

10. A device support as defined claim 1, wherein the receiving element can be pre-loaded when screwing in the screw.

11. A device support as defined in claim 1, wherein the cabinet frame is cuboidal.

12. A device cabinet as defined in claim 11, wherein corner connector elements are arranged at each of the four upper corners of the cuboidal cabinet frame that are each connected to three profiles via screw connections, and wherein in the lower section of the cuboidal cabinet frame, a rectangular base frame is provided, where its four corners are each connected with a vertically arranged profile of the cuboidal cabinet frame via weld or screw connection.

13. A device cabinet as defined in claim 11, wherein corner connectors are arranged at all eight corners of the cuboidal cabinet frame that are each connected to three profiles via a screw connection.

14. A device cabinet as defined in claim 11, wherein the corner connectors are cube-shaped.

15. A device cabinet as defined in claim 11, further comprising at least one covering plate suspended from the cabinet frame, wherein

the covering plate is provided with at least one locking strap,

the locking strap protrudes beyond a circumferential side edge of the covering plate

and the locking strap rests on an outer surface of the profile of the cabinet frame.