APPARATUS STAND

Abstract: The invention relates to a horizontally turnable laboratory apparatus (1), comprising a bottom plate (2) on which the entire apparatus rests. There is provided low friction means between the top surface of said bottom plate and the bottom surface of said apparatus, to render the apparatus easily turnable in the horizontal plane. It also comprises means (7) for restricting the movement of the apparatus to a circular movement around a point on the bottom plate (2).

Description: APPARATUS STAND The present invention relates to laboratory equipment for table use, and in particular to a an analysis apparatus comprising a tumable stand, for enabling access to all sides of said apparatus. A. Background of the Invention Often laboratory apparatus, designed to be placed on labora¬ tory benches, have a front surface where control panels are located, and a back side where e.g. electrical and other connections are made. It is often very awkward to make connections and disconnections, since it is not always possible or suitable to move said apparatus over the table. It is frequently required that such apparatus be firmly placed on the work bench in view of the nature of the system often being sensitive to vibrations etc., and thus it may be difficult to move it. Until now there have been presented no solutions to the problem of accessibility to all faces of an apparatus of the mentioned type. B. Summary of the Invention An object of the present invention is therefore to provide means for improving accessibility to all sides of a laboratory apparatus. This object is achieved by a an apparatus according to the invention, as defined in claim 1. A second aspect of the invention is a laboratory apparatus stand, as defined in claim 11. The advantage of the inventive stand is that it is very simple to have access to all sides of an apparatus mounted on such a stand, i.e. one may select any face as the front face. This is particularly advantageous for apparatus of a multi-module type, where in principle all faces actually may be regarded as a front face, depending on the application presently employed. Many types of laboratory apparatus, designed to be placed on laboratory benches, need to be equipped with auxiliary features, such as columns, solution containers, extra pumps, tubing etc. The common way of arranging such equipment is to provide a separate mounting stand, usually a vertical steel rod on a heavy base. The extra accessories are mounted on the stand by various types of clamps. Despite the base member being heavy, such an arrangement may easily become very unstable, and cumbersome and difficult to manipulate. A further object of the invention is to provide a solution to this problem with an apparatus of the mentioned type, taking advantage of the improved accessibility to all sides of the apparatus. A third aspect of the invention is therefore a laboratory apparatus, as defined in claim 1, which apparatus further is provided with means for mounting auxiliary equipment directly on the apparatus housing. The advantage of the provision of such mounting means is that it is very simple to build a configuration of auxiliary equipment, and the problem of instability of stand-alone devices is eliminated. The present invention will become more fully understood from the detailed description given herein below and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention. C. Brief Description of the Drawings Fig. 1 is a front view of a laboratory apparatus of a type for use on a laboratory work bench, which may employ the present invention; Fig. 2 is detail view of the lower part of the apparatus of Fig. 1, partly broken away, and showing an embodiment including the stand according to the invention; Fig. 3 is a side view of a laboratory apparatus of the type shown in Fig. 1, provided with mounting means for auxiliary equipment; Fig. 4 is detail cross-sectional view along A-A of the mounting means shown in Fig. 3, also showing attachment of a device thereto; and Fig. 5 shows a piece of auxiliary equipment, provided with an alternative embodiment of a mounting means . D. Detailed Description of Preferred Embodiments Fig. 1 shows a front view of a multi-module, stand-alone laboratory apparatus generally designated 1. The apparatus, which e.g. may be designed for performing chromatography, such as liquid chromatography, may comprise a number of devices, such as pumps, tubing for liquids and/or gas, electrical cabling and connections, reservoirs for liquid/gas, electronic modules, analysis cells etc., not specifically shown. All these items need to be easily accessible for maintenance and/or replacement purposes, and connection or disconnection. In a case where the apparatus is placed against a wall it is difficult to manipulate items located on its back side. In Fig. 2 there is shown a stand according to the invention, suitable for use together with the apparatus of Fig. 1. The stand comprises a bottom plate 2 on which the apparatus 1 rests. The bottom plate 2 is made of a material having a low friction surface, such as polypropylene. It may also be made of metal having a surface coated with such low friction material . Other materials conceivable for providing the low friction are polyethylene, PTFE (e.g. Teflon R ) , POM (e.g. Delrin R ) , PMMA or PVC. Polypropylene is the preferred material. For certain materials it may be necessary to provide pads of e.g. rubber to avoid sliding of the bottom plate on the bench. Polypropylene has proved to be an excellent compromise in that it provides enough slidability of the apparatus, and at the same time offers enough friction against the bench. In the centre of the bottom plate 2 there is provided a cylindrical hole 3. The opening of said hole facing upwards has a slightly smaller diameter than the opening facing downwards, such that there is formed a circular ridge or flange 11. Furthermore, there is provided a boss or hub 5, preferably made of steel, comprising two portions with differing diameters, such that it constitutes a cylindrical structure having a circumferential flange 4. The hub fits closely inside the hole 3 but with enough clearance 9 to be easily rotated in the hole. The hub is also provided with a central through hole 8. In the bottom surface 10 of the apparatus 1, there is provided a threaded hole 6. A screw 7 is fits in the hole 8 in the hub 5 and is secured in the hole 6. By tightening the screw, the apparatus is held in place on the bottom plate. However, by virtue of the clearance 9 between the flange like portion 4 on the hub 5 and the flange of the hole 3, rotation of the apparatus 1 around the centre point is not restricted by frictional force, and thus the apparatus is freely movable in a rotating fashion. Alternatively the hole 3 may have the form of a truncated cone, whereby the hub 5 of course must have a corresponding shape to fit well in said hole 3. Of course it is conceivable to arrange the apparatus in many other ways to achieve the desired turnability. One could e.g. provide the apparatus 1 with a circular edge or flange depending from the bottom surface, said flange enclosing a circular bottom plate, thereby restricting the movement of the apparatus to a circular movement. It may also be possible to let such a flange run in a circular groove in a bottom plate or vice versa. One could also envisage having ball bearings provided in a groove in the bottom plate or in the apparatus bottom surface, running in a corresponding groove in the opposite surface. However, by virtue of the very low rolling friction of such bearings, a solution like this requires that there be some kind of locking or securing means in order that the apparatus will not continue to rotate by itself. Neither is it of course necessary to have the screw secured in the bottom surface of the apparatus, as suggested above, but one could envisage an upwardly projecting pivot pin, mating in a receiving hole in the bottom surface of the apparatus. Thereby, it would become a very easy matter to lift off the apparatus portion and separate it from the bottom plate. In addition to all the fixed items of e.g. a chromatographic apparatus of the type shown in Fig. 1, such as pumps, tubing for liquids and/or gas, electrical cabling and connections, reservoirs for liquid/gas, electronic modules, analysis cells, etc., there may arise a need to provide auxiliary equipment for special purposes. In particular it may be necessary to perform experiments or tests where a plurality of chromatographic columns have to be used. In order to easily build a functional and simple configuration of such auxiliary equipment on the laboratory apparatus, in a preferred embodiment, the laboratory apparatus, generally designated 1, is provided with a number of essentially horizontally extending grooves or recesses 12, as shown in Fig. 3. Such grooves may be integrally formed in the housing 13 itself or may be comprised of profiles of e.g. aluminium having a suitable geometry. In Fig. 4, such a profile 14 is shown in greater detail in cross-section. As can be seen, the recess essentially has the shape of an "L" . The interior space of the recess is wider than the opening slot, such that the upper portion of the interior is hidden behind a depending ledge member 15. This depending ledge forms a hook member co-operating or interacting with a mating member 16 on an auxiliary item 17 that is mounted to the apparatus, as discussed above. A solution for securing a device in the recess, is to have a type of snap-fit connection, as schematically shown in Fig. 4. Thereby an item, such as a column holder, may be provided with a mating member 16 having a portion that protrudes upwards and fits closely inside the upper portion of the recess interior. This mating member is provided on a arm member 18 made of a resilient material in order to have a springing function in the vertical direction. Thus, in operation when the item is to be attached, the arm member 18 is pressed down, inserted into said slot, and when the pressure is released, the arm 18 springs back to its nominal position, whereby the mating member 16 rests in place inside the recess 12, locked behind the ledge 15, and thereby locks the extra item securely in the recess 12. As shown in Fig. 5, the mating member on the auxiliary equipment may simply be a horizontally arranged ledge 19 with a small rim 20 extending downwards. Said ledge is insertable horizontally through the opening slot, such that when the auxiliary equipment is brought back to horizontal again it is locked and secured in place in the recess. Instead of providing a ledge it is of course conceivable to provide a pair of or a plurality of hook means, having the same cross-section as said ledge, on the auxiliary item. Of course it is not necessary to provide recesses extending over the entire side of the apparatus. It is also within the scope of the invention to provide a plurality of holes at spaced apart locations over the surface. Each said hole will then be designed to match with a mating member in the same manner as described above in connection with the embodiment involving a recess. However, the provision of a recess, either as an integral part of the housing or as a separate profile, is the at present preferred solution. As is readily seen from the above, many modifications and variations are possible to the skilled man within the scope of the inventive concept as brought out in the appended claims.

Claims: CLAIMS : 1. A horizontally tumable laboratory apparatus (1) , comprising an apparatus part (1) ; a bottom plate on which the apparatus part (1) rests; low friction means provided between the top surface of said bottom plate (2) and the bottom surface (10) of said apparatus (1) , or integral with said bottom surface (10) or said bottom plate (2) , to render the apparatus easily tumable in the horizontal plane; and means (5, 6, 7) for restricting movement of the apparatus (1) to a rotation around a point on the bottom plate (2) . 2. The apparatus as claimed in claim 1, wherein the low friction means is provided by the bottom plate (2) being made of or having its upper surface provided with a low friction material, e.g. polypropylene. 3. The apparatus as claimed in claim 1, wherein the low friction means is provided by the bottom surface (10) of the apparatus (1) being made of or being provided with a low friction material, e.g. polypropylene. 4. The apparatus as claimed in claim 1, 2 or 3, wherein the restricting means is a pin member extending upwards from the bottom plate (2) and mating in a receiving hole in the bottom surface of the apparatus. 5. The apparatus as claimed in claim 1, 2 or 3, wherein the restricting means comprises a hub (5), fitting in a hole (3) in the bottom plate (2) with a clearance between the walls of the hole, and a screw (7) for securing said hub (5) to the apparatus part (1), by securing it in a mating threaded hole in said bottom surface (10) . 6. The apparatus as claimed in any one of claims 1 to 5, wherein the apparatus comprises a housing (13) provided with mounting means (12) for attaching auxiliary equipment (17) to at least one face thereof. 7. The apparatus as claimed in claim 6, wherein said means comprise a plurality of grooves (12) provided on at least one face of said apparatus (1), said grooves (12) being shaped to allow insertion of a mating element (16) provided on an auxiliary equipment (17) , and to lock said equipment in place when said mating element is inserted. 8. The apparatus as claimed in claim 7, wherein each said groove is a recess (12) having an opening slot and extending essentially horizontally across said face. 9. The apparatus as claimed in claim 7, wherein said grooves comprise a plurality of holes, said holes being provided at spaced apart locations over the surface. 10. The apparatus as claimed in claim 8, wherein said recess (12) essentially has a cross-section in the shape of an "L", the interior of the recess being wider than the opening slot, such that the upper portion of the interior is hidden behind a depending ledge (15) , said depending ledge thereby forming a hook member that is engageable with a mating member (16) on an auxiliary item (17) that is to be mounted on said apparatus face. 11. A stand for a laboratory apparatus, comprising i) a bottom plate (2) provided with low friction means on its surface, and having a through hole (8) provided in its centre, said hole having a wider opening facing downwards, and a narrower opening facing upwards; ii) a hub (5) fitting inside said through hole (8); iii) means (7) for rotatably securing a laboratory apparatus (1) to said bottom plate (2), by means of said hub (5) . 12. The stand as claimed in claim 11, wherein the low friction means is provided by making the bottom plate (2) of a low friction material such as polypropylene, polyethylene, PTFE, POM, PMMA or PVC, preferably polypropylene. 13. The stand as claimed in claim 11, wherein the low friction means is provided by making the bottom plate (2) of metal and providing it with a surface of a low friction material such as polypropylene, polyethylene, PTFE, POM, PMMA or PVC, preferably polypropylene.

Inventors: TAERNSTROEM ANDERS, TAERNSTROEM, ANDERS
Applicants: PHARMACIA BIOTECH AB, TAERNSTROEM ANDERS, TAERNSTROEM, ANDERS
Application year: 1997
Main classification: B01L9
IPC codes: B01L9