TRESTLE STAND

Abstract: Trestle stand, which exhibits legs (2), which can be folded up, and can be locked in swung-out position in an efficient and safe manner. By means of this invention a trestle stand is obtained, which is simple to handle, safe to use and which occupies a minimum of space in folded-up condition. The trestle stand, which comprises a central column (1), which is provided with supporting legs (2) and a supporting bar (3), which can be introduced into the central column (1) and be locked to the same in a desired height position, exhibits inside the column (1) a locking means comprising a locking body (16), which in connection with the use of the trestle in a secure manner locks struts (10), which are connected with the supporting legs (2), which in their turn are hinged on the central column (1).

Description: Trestle stand The present invention relates to a trestle stand of the kind exhibiting a central column provided with supporting legs and a vertically adjustable supporting bar, which can be locked to said column in any desired height position. It is an object of the invention to provide a trestle stand of the kind mentioned above, but which is provided with supporting legs capable of being swung out on hinges, which legs in a simple and efficient manner permit being swung .into a desired position and in swung ' out posi¬ tion to be locked, whereby the trestle stand in folded together condition will require a minimum of space only, its construction not permitting an " unintentional collapse, by way of example, when the trestle supports a load. Said object is reached by means of a trestle stand according to the present invention, which is substan¬ tially characterized by its legs being hinged on the central column, which is designed in the form of a tube surrounding a locking body, which is movable between two end positions, said legs exhibiting struts, which in the swung out position of the legs can be introduced in openings of the central column, which holes are adapted to receive said struts, said locking body in a bottom position cooperating with said struts by locking the same in such a manner that their extraction out of said holes is impeded. In the following an example of an embodiment of the invention is described, reference being made to the accompanying drawings, in which Fig. 1 is a perspective view of a trestle stand designed according to the invention and showing the legs in swung out and locked position, Fig. 2 shows the same trestle stand with its legs folded up, ' Fig. 3 is a longitudinal cross-sectional view through the central column of the trestle stand and the locking means enclosed inside the same as well as one of th legs of the trestle stand attached to the central column in swung out and locked position, and Fig. 4 is a view of the same central column with the leg in the position, in which it is folded up against the same. The trestle stand, which by way of example i intended for the trestling of a vehicle, substantially comprises two elements, which can be detached from each other, which is clearly evident from Fig. 1, viz. a central column 1, which is provided with supporting legs 2, and a vertically adjustable bar 3 located in the mid portion of said column. This supporting bar 3 is intended to be locked to the central column 1 in any desired height position by means of a locking pin 4, which for this purpose is intro¬ duced through two holes 5 made in the upper portion of the central column and located right in front of each other and two optionally chosen holes 6 made in the bar 3 and likewis located right in front of each other. The locking pin 4 is held by means of a chain 7 to the column 1, and the upper portion of this column is provided with a supporting plate 8, on which the vehicle rests. In order to make possible that the legs 2 shall occupy a plane position on the founda tion, these legs are provided with plane supporting plates at their lower end, and close to said plates there are struts 10 hinged on the legs 2, which struts with their fre ends are introduced into and held in slits 11 made in the lower portion of the central column. By means of these struts 10 the folding up of the legs 2 is impeded, when the trestle stand is in use, and the locking of said struts 10 is made by means of a locking device located in the interio of the central column 1, the design and function of which will now be described more in detail with reference to the Figs. 3 and 4. A holding down' ring 12, which supports a transversally extending welded-on pin 13, which in its turn supports a sliding shaft 14 extending in the direction of the central axis of the ring 12, is introduced into and welded-on to the lower end of the central column 1. Said sliding shaft 14 in its upper portion supports a stop dog 15, which for example comprises a nut 15 screwed onto the shaft 14 or a transversal pin or any other suitable stop element welded-on to said shaft 14. A spacer tube 16 is with its lower endlid 17 in sliding arrangement provided along the sliding shaft 14 between the transversally extending pin 13 and the nut 15, which details thus constitute terminal stops in order to limit the displacement of the spacer tube 16 along the shaft 14. In the illustrated example the support¬ ing legs 2 are three in number, each one comprising a strut of long extension bent in such a manner that it acquires a U-shaped cross-section, and each strut is in its bottom portion provided with said supporting plate 9. The leg 2 is hinged on the outer upper portion of the central column right under a supporting ring 1A, which serves the purpose of an additional stop dog in case there should be any fault in the hinge arrangement of the leg 2. An ear 18 pointing laterally in outwards direction or a sleeve for bearing purpose supports the mid portion of a through shaft-pin 19, which with its respective free ends in its turn supports each one of the two leg flanges 2A, 2B of the leg 2. The upper portion of the leg 2 exhibits a pointed shape with an edge portion 2C, which in a swung-out leg 2 extends along the outer wall of the central column 1. The lower end of the leg 2 in its turn supports the strut 10, which at one of its ends is provided with a hole, through which a shaft pin is introduced and fastened to the flanges 2A, 2B of the leg. As is shown in Fig. 3 the strut 10 can be entirely swung in¬ wards, so that it occupies a position, in which it entirely grips around the leg 2 because of the U-shaped profile of said leg 2. At its outer fr,ee end the strut 10 exhibits a notch 21, which in a swung-out position of a leg 2, see Fig. 4, grips around the upper edge 12A of the holding down ring 12 and the bottom portion 11A of the slit 11 made in the central column 1. In this gripping position the strut 10 is held by means of the lower end 17 of the spacer tube 16, said end bearing against the top portion of the outer end o the strut 10, which with its notch 21 forms a hook 10A. The spacer tube 16 is in its turn impeded from moving in upward direction by the locking pin 4, which at the same time lock the supporting bar 3 to the central column 1 in the desired height position of the bar 3. Thus, the hook 10A is impeded from being brought out of engagement with the edge of the slit 11A and the upper edge of the holding down ring 12A. B this arrangement the strut 10 cannot be swung out of the slit 11, so that the leg can be folded up, unless the lock- ing device is released. The folding up of a trestle stand with its legs 2 occupying a swung out position takes place in the following manner: The supporting bar 3 of the trestle stand ■ which in this connection does not carry any load, is lowere _jy extracting the pin 4 from the holes 5 and 6 of the bar 3 and the column 1 respectively. The bar 3 can thereafter be extracted from the column 1, whereafter the column 1 is suitably turned upside down, so that its bottom end with th slit will be located upwards. The spacer tube 16 then slide along the sliding shaft 14 and comes to a stop, when its en lid 17 arrives in bearing contact with the nut 15. The hook portion 10A of the strut 10 provided with the notch 21 can then be brought out of engagement with the edge 11A of the slit and the upper edge 12A of the holding down ring and be swung out of the slit 11. The leg 2 can then be freely folded up against the column 1, whereby the strut 10 will b embraced by the outer flanges 2A, 2B of the leg 2. After all of the legs 2 have been folded up, the supporting bar 3 is again brought downwards in the column 1, whereafter it is locked by the pin 4. In this condition the trestle stand requires very little space and can therefore be stored in narrow quarters. In its folded-up condition the legs 2 can suitably be held by means of a device, which surrounds the same and the column 1, so that the legs will not swing out when stored. Swinging out the legs takes place in the same manner as described above, but in reverse order, i.e. the leg 2 is swung out, the strut 10 is introduced through the slit 11, so that the hook 10A with its notch grips around the edges 11A, 12A. The trestle stand is thereafter turned in such a manner that the spacer tube 16 is brought downwards in the column 1 and is locked by means of the pin 4. The invention is not limited to the embodi¬ ment described above and illustrated in the drawings by way of example only, but can be varied as to its details within the scope of the following claims.

Claims: C l a i m s 1. Trestle stand of the kind exhibiting a cent¬ ral column (1) provided with supporting legs (2) and with a vertically adjustable supporting bar (3) that can be locked to said column (1) , c h a r a c t e r i z e d b y the legs (2) being hinged on the central column (1) , which is designe as a tube (1) , and which surrounds a locking body (16) , which is displaceable between two end positions (13, 15), and by the legs (2) exhibiting struts (10) , which in the swung-out position of the legs (2) can be introduced into openings (11) of the central column (1) , which holes are adapted to said struts, said locking body (16) in a lower end position cooperating with said struts (10) locking the latter ones, so that their extraction out of said openings (11) is impeded. 2. Trestle stand according to claim 1, c h a ¬ r a c t e r i z e d b y the locking body (16) comprising a spacer tube (16) - which with its lower end (17) when locking the legs (2) in their swung-out position bears against stop dogs on the free pivotable ends of the struts (10) , which ends are designed as hooks (10A) and grip around the edge (11A) of a corresponding opening (11) of the central column, whereby the movement of the spacer tube (16) in upwards direction from said stop dog in the locking position is limited by a locking pin (4) , which locks the supporting bar (3) to the central column (1) in a desired height position. 3. Trestle stand according to anyone of the preceding claims, c h a r a c t e r i z e d b y the bearin means for each respective leg being constituted by a hinge comprising an ear (18) or a bearing sleeve projecting side- wise from the upper end of the central column (1) ' and suppor ing the central portion of a shaft pin (19) , which with its respective ends in its turn supports the upper end of the leg (2) by means of two at a certain distance from each other located lateral flanges (2A, 2B) formed by the support ing leg (2), which is bent in such a manner that it acquires a U-shaped cross-section. 4. Trestle stand according to claim 3, c h a ¬ r a c t e r i z e d b y each one of the respective support- ing legs (2) at its lower end supporting a strut (10) , which is hinged on a shaft pin (20) , which extends between the respective flanges (2A, 2B) , whereby said strut (10) from its swung-out locking position, when the locking body (16) is released, can be entirely folded up in the space formed between the two lateral flanges (2A, 2B) of the leg, which permits the leg (2) to be folded up into a position, where it is substantially parallel to the central column (1) close to the same. 5. Trestle stand according to anyone of the claims 2-4, c h a r a c t e r i z e d b y the spacer body (16) , which is enclosed in said supporting bar (3) , which in its turn is displaceably mounted in the central column (1) , with a lower end lid (17) surrounding a sliding shaft (14), which with its lower end is supported by a transversal support (13) rigidly mounted in the lower end of the central column (1) , whereby said spacer body (16) is displaceable along the sliding shaft (14) between said support (13) and a terminal stop (15) provided at the upper end of the sliding shaft (14) . 6. Trestle stand according to anyone of the preceding claims, c h a r a c t e r i z e d b y the open¬ ings (11) of the central column (1) comprising slits (11) , which extend along said column (1) , and which are located at the lower end of said column, whereby the lower edges (11A) of the slits (11) constitute stops for the struts (10) , when the supporting legs (2) are swung-out and locked. •

Inventors: JOENSSON L
Applicants: BVS PLATMEKANO HB, JOENSSON L, HB B V S PLATMEKANO
Application year: 1981
Main classification: F16M11
IPC codes: F16M11