The present invention relates to a crossbeam, in particular for holding and supporting lifting tables to be carried by at least one leg, and in particular by two or more in row arranged legs, which all are being supported and held in position by the crossbeam.

Lifting tables may be of various kinds. In relation to the present invention lifting tables may be understood aε in level adjustable tables for the carrying and suppor¬ ting of for example electronic data handling equipments or other kinds of working tables, which do not necessarily and literally to be tables, but for example can be like book stands, for pidgeon—holing as used when sorting mail, etc.

It is of importance that certain pracitcal demands are fulfilled when lifting in such cases, namely that that which is lifted safely is kept in position, so that it does not shiver when exposed to lesser mechanical influen¬ ces when being used for their purposes. It is also impor— tant that in case of such larger influences a changing of their positions may take place so that they become slan¬ ting, and in these cases such influences furthermore may result in the exertion of large forces of moments which may bend the above mentioned carrying legs.

But, a further problem exists, which unto today not has been solved rather good and not in any si pel manner.

The problem is the following. To explain this a basic carrying stand may be used as an example. The stand may comprise two horizontally and in parallel arranged and below as base functioning lengthy and like girder or beam positioned elements which are connected with each other through a crossbeam or transverse girder of the type mentioned initially above. This crossbeam carries or supports in particular two legs which may be of telescopic type and at their upper portions carry or support the above mentioned equipments, which can be working table

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plates, pidgeon—holing stands or the like. Hereto it is necessary that these legs have their upper portions mutu¬ ally connected by means of an element, which may be frame or beam like and which carries the mentioned elements to be carried. The purpose of such framelike means is to achieve a sufficiently strong and rigid interconnection, so that a minimum of shivering during operation is ex¬ perienced. Through these interconnecting means a dimi¬ nishing and a better distributing of the carrying forces which are recei ved and transmitted by the crossbeam car¬ rying the legs and by the employed fastening arranged between the crossbeam and the legs is achieved.

It is the task according to the present invention to provide a crossbeam of the initially mentioned type by means of which crossbeam the holding of the mentioned legs is made functionally very strong, and whereby the cross¬ beam itself has been made very resistant and stabile when moments of force are exerting influences unto the upper portions of the legs, and furthermore sufficient space should be provided for the arranging of a common drive mechanism for telescopic lifting means being comprised in the legs, and whereby these telescopic lifting means are synchronously driven. The strength and the mechanical stability should preferably be so much improved that any frame like or connecting means no longer necessarily have to be mounted between the upper portions of the legs, i.e. that the achieved stability is achieved to be better without such connecting means aε compared to earlier devices where such connecting featLireε were comprised. This task has been solved by means of the present invention by providing a crossbeam of the intialiy mentio¬ ned type through the invention being specified in that the crossbeam is composed of at least two, into each other inserted, profiles or channel irons each preferably with C-shaped cross-section or being C-εectionally shaped.

whereby the C—shapes may have substantially parallel running top and bottom portions, and whereby the apertures of the preferably C—shaped sections of the profiles or channel irons are oriented in opposing directions, thus pointing away from each other, and whereby the cavity of the C-shape of one of the profiles or channel irons is cross—sectionally fitting in shape with the periphery of the other profile or channel iron is able internally, while fiting at least in the vicinity of the borders of the aperture of the C-shape and fitting at least with a portion of the top and bottom surfaces of the C—shape thereof, to receive the other profile or channel iron, and whereby the externally arranged of the profiles or channel irons at the portion of its C—shape being located opposite to the aperture of its C—shape, hereby including at least a part of the external C—shape top and bottom surfaces of the external profile or channel iron, comprises openings in shape adapted to receive the legs to be supported by the crossbeam, and whereby the C—shaped profiles or chan- nel irons are fastened unto each other by joining means and/or welding at least at the transitional areas between the internal C-shaped profile or channel iron and the top and bottom portions in proximity of the legs.

A beam structure aε this according to the invention has shown itself tσ be very well suited and stabile. The achieved structure is so gσod that the legs carried by the crossbeam do not require any connecting frame like element mounted between their upper ends. The upper portions of the legs may singly vertically upwards be freely protrui- ding without any interconnecting element between the upper free ends of the legs. This makes it even more easy to use the carrying stand in practice, because that which is to be carried by the legs more easily may be mounted unto them.

In the following some further developments according to the invention are described. Herethrough, even better strength and stability may be achieved. Also a device, which is very simple and which easily may be installed and after the installation is hidden in the beam structure, and whereby the structure protects users against touching working drive elements, and which device si ultaneously may influence and drive for instance two on the crossbeam mounted legs for lifting purpose, is going to be deεcri— bed. It should be mentioned, that a very strong and stabi¬ le structure has been achieved, to indicate this an example is given: A for a structure of this kind in ge¬ neral very dangerous load may be the application of a gravitational load presenting a weight of 200 kgs being applied vertically downwards against the outer end of a 1 meter long horizontal rod or beam which is duely fastened to the upper portion of a aforementioned leg. But, even this load only results in a very miniature displacement aε the reaction of the structure. Corresponding torεional moment influences are also easily absorbed and dealt with by the beam structure. These are only mere examples.

According to the invention it is in practice easy to achieve that the legs which are received by and carried by the crossbeam through joining means and/ or welding are faεtened to both of the mutually inserted profiles or channel irons of the crossbeam.

An improved embodiment may according to the invention be achieved in that the received legs to be supported by the crossbeam by means of joining meanε and/or welding are fastened at the transitional areas between the internal C— shaped profile or channel iron and the to and bottom surfaces of the C—shape.

In particular it may become easy to mount the cross¬ beam and simultaneously have good accesε to the internal side of the ends of the external profile when accordinc to

the invention the length of the inner profile or channel iron of the mutually inserted profiles or channel irons is shorter than that of the external of the profiles or channel irons. In this respect an improved strength is attained when according to the invention preferably internally in the external profile or channel iron and at least at the ends of the internal profile or channel iron transverse arran¬ ged means are provided having a shape which fits with the cross—sectional internal contour of the external profile or channel iron, and whereby the transverse arranged means preferebly are fastened at least onto the external profile or channel iron by means of joining means and/or by wel¬ ding. A further embodiment by means of which improved access and easier mounting externally of the crossbeam is according to the invention attained when a transverse arranged means is positioned spaced from the terminating ends of the external profile or channel iron for the providing of a closed space or enclosure just inside the terminating ends of the external profile or channel iron for the receiving of fastening means for the fastening of the crossbeam onto external means which carry and support the crossbeam. An advantageous embodiment permitting the receiving of drive means and mechanismε for driving teleεcopic de¬ vices, which may be- suitable spindle deviceε, and which devices are foreseen mounted within the legs mounted onto the crossbeam is according to the invention achieved when the remaining and thus of the inserted profile or channel iron not occupied space inside the external of the pro¬ files or channels irons is arranged to have a sufficiently- large size to receive a drive means and a common drive power transmission means, such aε a tooth belt, arranged between the drive means and teleskopic lifting means being

provided in the legs supported by the crossbeam. Embodi¬ ments of this kind fulfil the earlier demands being posed to such drive means and drive mechanismε.

In this respect it is according to the invention 5 advantageouε when the portion of the external profile or channel iron of the into each other iπεerted profiles or channel ironε not being in shape adapted to fit with the contour of the internal of the profiles or channel ironε in crosε—εection iε wider than the internal profile or 0 channel iron.

In respect to dimensioning the device when a cross¬ beam according to the invention is made of bend steel plates it is as well possible as advantageous when such a portion of the cross—section of the external profile or 5 channel iron being wider as compared to the inner profile or channel iron iε made to have substantially the same internal width as the free width that the cross—section, in a perpendicular hereto oriented direction, has inside the inner cross—section of the external profile or channel 0 iron.

In this respect a strong crosεbeam iε attained when according to the invention the proportional relation between the two tranεverεal widths of the cross—sectional C—shape of the internal profile or channel iron iε of the 5 size of roughly lϊl.5, and when the proportional relations between, on one side of the relations, the two transversal widths across the empty—spaced internal cross—εectior. within the external profile or channel iron and. on the other side of the relations, the already mentioned widths ϋ of the internal profile or channel iron have sizes of roughly up to 4, namely as 4 times the smaller transverse widths of the internal C—shaped profile or channel iron, and that prεferablv the two last mentioned widths, i.e. across the empty spaces within the external profile or

3.5 channel iron, roughly are equally sized.

Embodiments according to the invention are described in more details aε follows under reference to the drawing, in which:

Fig. 1 in the perspective illustrates a crosεbeam 1 according to the invention supporting two legs

2AA and 2BB able to carry one or more not shown objects, which may be lifting tables, stands for pidgeon—holing, etc., and whereby the crossbeam 1 itself is resting on two legs 3A and 3B and is supporting two lower leg portions 2A and 2B for 2AA and 2BB, Fig. 2 iε an exploded view illustrating in the per¬ spective a crossbeam 1 according to Fig. 1 and which is able carry two indicated legs 2A and 2B,

Fig. 3 shows in the perspective the two profiles or channel irons 4 and 10 of the crossbeam 1 in assembled condition being embodied as accor¬ ding to Fig. 2, Fig. 4 illustrates cut IV-IV according to Fig. 3, i.e. by showing a longitudinal cross—section through the area around the leg 2A, Fig. 5 shows cut V—V according to Fig. 4, Fig. 6 shows cut VI—VI according to Fig. 4, and Fig. 7 illustrates the cut shown in Fig. 4, but also showing an arranged gearmotor M, which through a toothbelt B2 is able to drive a lifting device εpindle 2B which iε mounted in one of the legs, here shown aε leg 2A, but such a device might similarly" also be mounted in more than one leg, such aε within the legε 2A and 2B. In the single Fig.s of the drawing same elements or elements having the same or similar functions carry the same signs of reference.

As just εpecified in relation to the drawing a cross¬ beam 1 iε adapted to εupport two εhown, as telescopic elements, embodied legs 2A and 2B having telescopic leg portions 2AA and 2BB and all being embodied according to the invention to fulfil itε purpose aε earlier deεcribed. The crossbeam 1 is resting on two the beam carrying legs 3A and 3B which rest on a not shown supporting means, or the crσεεbeam 1 might reεpectively be reεting directly on a supporting means or upon a number of any kind of εui— table εupporting means.

The structure of the crossbeam iε visible in the Fig.s 2 through 7.

The croεεbeam 1 is composed of in particular two, here aε somewhat polygonally contoured shown, C-shaped profiles or channel ironε 4 and lO. The C—aperture of the C-shape iε in one of the profiles or channel ironε 4 confined by border portions 4D, 4E which, aε it iε parti¬ cularly shown in Fig. 3 and Fig. 4, internally are abut¬ ting against the internal midportioπ IOC of the other profile or channel iron 10, and simultaneously, the top and bottom portions of the C—shape of the first profile are abutting against the internal side of the top and bottom portions of the C—shape of the other profile or channel iron 10, respectively with 4A abutting against 10A and with 4B abutting against lOB.

Openings 200A and 200B, aε well aε 20A and 20B, are reεpectively provided in the two profiles or channel ironε 4 and 10 around the legs 2A and 2B. These openings are εhaped rather oversized and comprise clearly closely abutting and besides each other laying border portions along the top and bottom portions of the C—shape of the two profiles or channel ironε 4 and 10 so that small horizontalI oriented and εlanting oriented εurfacε por¬ tions are formed. It iε contemplated that these areas have to be areas for assembling, i.e. for joining, and also for

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access when putting joining means in place. Such joining means can for example be screws, pins, or possibly also welding, just as in Fig. 5 indicated by means of arrows A and 3. Blot—shaped openings are provided, as indicated by means of Fig. 2, in the internal profile or channel iron 4 at the locations 4EE and 4FF. The slot—shaped openings are . as in particular indicated in Fig. 5, namely aε indicated by means of arrows and E, contemplated to give admittance to welding tools when welding the leg 2A. respectively the leg 2B, to the inner profile or channel iron 4 including simultaneously to the adjoining top and bottom portions of the C—shape of the external profile or channel iron 10. On the other hand, it is also possible at the areas at the arrows D and E to arrange other suitable adjoining means, which could be screws and pins.

Suitable through—hoieε or through—openings 20B for the passing-through of for example a spindle 28 which is to run internally in the legs, such aε illustrated within the leg 2A in Fig. 7, may be provided at the midportion of the C—εhaoe of the internal profile or channel iron 4 such aε it in particular may be underεtood of Fig. 2. The end portion of the εpindle 28 may be provided with a tooth- wheel 29 which gripε into and iε driven by a toothbelt S2 which on the other hand is driven by a suitable gearmotor 8 which also iε referred to by means of reference sign M and which iε fastened onto a baeepl te 8A being kept in place by means of for example εcrewε ST at the internal border portions 10D and iOE of the external profile or channel i on 10. To adapt this profile lO to receive SLich a motor 3 and also with the purpose to strengthen the profile mechanically the profile can comprise a mo>-<= wide spaced portions 10G and 10H below the area comprising the internal strength giving profile or channel iron 4.

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The described beam structure has shown itself to be exceedingly strong, and it is able easily and rigidly to support and fixly hold the upward protruding legs 2A, 2AA and 2B, 2BB, and furthermore, an upper additionally strengthening and connecting, i.e. interconnecting, for example frame like, means between the legs, where they are connected to the object or objects to be carried bv them, iε no longer demanded.

A transverse wall or bul head means 5A which compri— εeε a lower base portion has shown itself advantageouε particular in respect to hold the lower portion of the external profile or channel iron 10 in place in a stabile manner. These two items cooperate advantageously with a plate means 5B aε mounting and fastening means, for example together with bolts 7, for the fastening of the croεεbeam 1 to a baεic support means.