NL2007122C2

NL2007122C2 - Linear guide and method for forming a linear guide.

Info

Publication number: NL2007122C2
Application number: NL2007122A
Authority: NL
Inventors: Andreas Petronella Maria Stijns
Original assignee: Thomas Regout Internat B V
Priority date: 2011-07-15
Filing date: 2011-07-15
Publication date: 2013-01-17
Also published as: DE112012002983T5; WO2013012325A1

Abstract

Linear guide, comprising a first and second guide element and intermediate bearing means, wherein the first guide element has a substantially C or U shaped cross section part, comprising at least a first wall part and two first flanges, wherein the second guide element has a substantially C or U shaped cross section, comprising at least a second wall part and two second flanges, wherein the bearing means comprise at least three wheels, carried on axis mounted to the second wall part, wherein at least a first of the three wheels runs on a first of the first flanges and at least two of the wheels run on the other of the first flanges.

Description

P94990NL00

Title: Linear guide and method for forming a linear guide.

The invention relates to a linear guide.

Linear guides are commonly used for suspension of moveable elements and guiding such elements along a linear path of movement, for example in vending machines, tooling, ATM’s and the like.

5 From the prior art a linear guide is known, for example from PBC

linear, Pacific Bearing Company, USA, e.g. type CR 20, 30 or 45, comprising a guide element having a length direction and a substantially C-shaped cross section, comprising a first wall section and two flanges, at opposite sides of the first wall section, extending substantially parallel to each other and in the 10 length direction, forming running tracks, frame or such support structure. A solid metal block is provided with openings for mounting the block to a three wheel axes extending from a side of the block facing the guide element, each carrying a relatively large wheel, extending in the guide element, between the flanges. A first of the wheels runs on a first of the running tracks, whereas the 15 other two wheels run on the opposite second running track. The first wheel axis is mounted by an excenter element to the block, such that the position of the axis and thus of the wheel can be adjusted in a direction perpendicular to the first running track, allowing the distance between the contact point of the first wheel with the first running track and the contact points of the other two 20 wheels with the second running track to be adjusted to the distance between the running tracks. This is important for the bearing capacity of the linear guide and the accuracy and the feel of the linear movement of the block relative to the guide element. Such linear guides are complex in construction and expensive. Another problem is that for example brakes, catches, latches 25 and the like cannot easily be provided. Furthermore the total thickness of the linear guide is large, which can be problematic for proper mounting of the guide.

2

An aim of the present disclosure is to provide a linear guide which is an alternative for the known linear guide. An aim of the present disclosure is to provide a linear guide which obviates at least one of the problems of the prior art. A linear guide according to the present disclosure is preferably 5 relatively simple in construction and/or relatively thin and/or less expensive.

In an aspect a linear guide of this disclosure can be characterised by a first and second guide element and intermediate bearing means, wherein the first guide element has a substantially C or U shaped cross section, comprising at least a first wall part and two first flanges. The second guide element can 10 have a substantially C or U shaped cross section, comprising at least a second wall part and two second flanges. The bearing means comprise at least three wheels, carried on axis mounted to the second wall part. At least a first of the three wheels runs on a first of the first flanges and at least two of the wheels run on the other of the first flanges.

15 In an aspect a linear guide of this disclosure can be characterised by a first and second guide element and intermediate bearing means, wherein the first guide element has a substantially C or U shaped cross section, comprising at least a first wall part and two first flanges, wherein the bearing means comprise at least three wheels, carried on axis mounted to the second guide 20 element. At least a first of the three wheels runs on a first of the first flanges and at least two of the three wheels run on the other of the first flanges. The second guide element has a substantially C or U shaped cross section, comprising at least a second wall part and two second flanges, wherein the axis are mounted to the second wall.

25 The axes of the wheels can be mounted in a fixed position, whereas the wheels can be positioned such that the first flanges are forced slightly outward by the wheels. Preferably there is an uneven number of wheels provided. At least one of the two second flanges can extend at least partly between the first flanges. In embodiments both of the second flanges can 3 extend at least partly between the first flanges. At least one of the wheels can extend through an opening or cut out in at least one of the second flanges.

In an aspect the present invention can be characterised by a method for forming a linear guide, wherein a first and second guide element are 5 formed and wherein the first guide element has a substantially C or U shaped cross section, comprising at least a first wall part and two first flanges. The second guide element can have a substantially C or U shaped cross section, comprising at least a second wall part and two second flanges. At least three wheels are mounted on axis extending from the second wall part or at least 10 three wheels on axis are mounted on the second wall part. The second guide element is slid at least partly into the first guide element, such that at least a first of the three wheels runs on a first of the first flanges and at least two of the three wheels run on the other of the first flanges. The wheels are preferably positioned such that the first flanges are at least partly forced apart 15 by the wheels.

Advantageously, by using guide sections as described above, stops can be provided easily by elements formed from and/or elements mounted on the guides, extending into the space between the first and second wall parts. An advantage of adding these stops can be that a symmetric stopping force 20 distribution on the guide sections can be realised. An additional advantage of these stops can be that they can be made of the same material as the guides and that they do not have to stop against a wheel.

Linear guides according to this description can include but is not limited to automation, packaging, material handling, environmental energy, 25 HVAC, medical and office equipment, vending machines and ATM’s.

In elucidation of the present invention linear guides and methods for forming a linear guide shall be described in relation to the drawings, wherein embodiments are shown, by way of example only. The drawings show:

Fig. 1 schematically in frontal view a linear guide, with partly 30 broken away second guide element; 4

Fig. 2 schematically in frontal view a linear guide, with partly broken away second guide element, in a second embodiment;

Fig. 3 schematically in frontal view a linear guide, with partly broken away second guide element, in a third embodiment; 5 Fig. 4 schematically in side view a linear guide according to the invention;

Fig. 5 schematically in side view a linear guide according to the invention, in a second embodiment;

Fig. 6 schematically in side view a linear guide according to the 10 invention, in a third embodiment;

Fig. 7 is schematic frontal view four embodiments of a linear guide, here shown as example comparable to fig. 1, wherein different numbers of wheels and different auxiliary elements and provisions are show;

Fig. 8 detailed side view of part of a linear guide, for example 15 according to figures 4-6, showing in detail a possible embodiment of a wheel in a guide rail;

Fig. 9 schematically in frontal view a linear guide, with cut away flange portions to provide space for auxiliary means, in a further embodiment.

In this description and the drawings the same or similar elements 20 have the same or similar reference signs. In the embodiments described guide elements are shown which can be made of metal, such as but not limited to steel, aluminium, titanium or alloys thereof. Guide elements could also be made entirely or partly of other materials, such as but not limited to plastic or ceramics. In embodiments the first and second guide elements can be made of 25 the same or different materials.

In this description words like “substantially”, “about” or “generally” are to be interpreted as meaning at least including deviations of a dimension of 10% or less, preferably 5% or less or deviations from a shape of form which would still be considered by a person skilled in the art as falling with the 30 definition referred to.

5

In this description guide elements will be described as forming part of a linear guide. Such elements can have a length direction defining an element length aspect. The elements have a cross section substantially perpendicular to the length direction. In embodiments the cross section can be 5 substantially constant over the length of the guide element. In this description guide elements are described having a substantially C- or U-shaped cross section, which has to be understood as at least including cross sections having a wall section and two flanges, extending from opposite sides of the wall section. The flanges can extend substantially parallel to each other. The wall 10 section and flanges do not have to be straight. The flanges may have a running portion defined for example by indentations formed in the flanges. The wall can have profiling, for example reinforcement ridges, indentations and the like.

In embodiments the guide elements can be nested, at least partly, by 15 having the flanges of a profile extending at least partly and in embodiments substantially entirely between the flanges of the other of the guide elements.

In embodiments the guide elements can be nested, at least partly, by having one of the flanges of a first profile extending at least partly and in embodiments substantially entirely between the flanges of the other of the 20 guide elements, one of the flanges of the other guide element extending between the flanges of the first guide element.

In this description wheels have to be understood as including bearing elements provided rotationally on or by an axis and having at least one peripheral running surface. The axis can be a real axis, such as an axle or 25 rod, or, in embodiments, can be a virtual axis. If a real axis is used, this can be mounted to a guide element, the wheel rotatable on said axis. Alternatively the axis can be part of or fixed to the wheel and rotationally mounted to a guide element. In a linear guide there can be any number of wheels. In embodiments there can be an uneven number of wheels. Wheels can be provided in an 30 isosceles triangle setting, if there are three wheels, or in substantially parallel 6 rows, if there are more than three wheels. Alternatively, the wheels can be provided in an asymmetrical triangle setting, for example if there are three wheels, wherein two wheels placed in a row parallel to one of the flanges form the base of the triangle. The wheels can all have a similar diameter, or some 5 can have differing diameters.

In a linear guide according this description guide elements can be made from but are not limited to sheet material, such as metal sheet or plate, such as but not limited to strip material. Guide elements can be made using known metal working techniques, such as but not limited extrusion, moulding, 10 stamping, forging, folding, drawing, press brake forming and/or roll forming.

The above given general description can all be applied in the embodiments as discussed hereafter, singularly or in combination.

In fig. 1-3 embodiments of a linear guide 1 are shown, having a length direction L which is parallel to a relative direction of movement V of the 15 guide elements. The linear guide 1 comprises a first guide element 2 and a second guide element 3. The first guide element 2 has a first length Li and the second guide element 3 has a second length L2, the second length L2 being smaller than the first length Li. The second length L2 can be about half the first length Li or less, for example about one third or less, such as but not 20 limited to one fourth or less. The first guide element 2 as shown has a first wall part 4 and two first flanges 5, 6 extending from opposite edge portions 7, 8 of the first wall part 4, in substantially the same direction, as is also shown in e.g. fig. 3 and 4. The second guide element 3 as shown has a second wall part 9 and two second flanges 10, 11 extending from opposite edge portions 12, 13 of 25 the second wall part 9, in substantially the same direction, as is also shown in e.g. fig. 4-6. The first and second flanges 5, 6 and 10, 11 can extend substantially parallel to each other and substantially perpendicular to the first 4 or second wall part 9 respectively.

In embodiments of linear guides of this description the first and 30 second wall parts 4, 9 may extend substantially parallel to each other, the first 7 flanges 5, 6 extending in the direction of the second wall part 9 and the second flanges 10, 11 extending in the direction of the first wall part 4.

In fig. 4 a cross sectional view of a linear guide 1 of fig. 1 is shown, along the line IV — IV in fig. 1, disclosing the second flanges 10, 11 5 substantially extending between the first flanges 5, 6 to close to the first wall part 4. The first flanges 5, 6 each have or form a groove 14, 15 such as a substantially V shaped deformation, open towards each other, for forming one or more running surfaces 16 for bearing means 17 as to be discussed.

In fig. 5 a cross sectional view of a linear guide 1 of fig. 2 is shown, 10 along the line V - V in fig. 2, disclosing a first 10 of the second flanges 10, 11 substantially extending between the first flanges 5, 6 to close to the first wall part 4, whereas a second 6 of the first flanges 5, 6 extending between the second flanges 10, 11. At least the first of the first flanges 5, 6 and the second 11 of the second flanges 10, 11 each have or form a groove 14, 15 such as a 15 substantially V shaped deformation, open towards each other, for forming one or more running surfaces 16 for bearing means 17 as to be discussed.

In fig. 6 a cross sectional view of a linear guide 1 of fig. 3 is shown, along the line VI - VI in fig. 3, disclosing the first flanges 5, 6 substantially extending between the second flanges 10, llto close to the second wall part 9. 20 The first flanges 5, 6 each have or form a groove 14, 15 such as a substantially V shaped deformation, open towards each other, for forming one or more running surfaces 16 for bearing means 17 as to be discussed, especially wheels 18. When the running surfaces 16 are provided as part of a groove or substantially V shaped part of the flanges 5, 6 and/or 10, 11 side ways 25 movement of the wheels 18, i.a. towards or away from the first and/or second wall parts 4, 9 can be prevented, thus preventing separation in that direction of the guide elements 2, 3.

As can be seen especially in fig. 1 - 3 a number of wheels 18 can be provided, such as an uneven number, on axis 19 mounted to the second guide 30 element 3, running on the first guide element 2, especially the first flanges 5, 6 8 thereof. One or more of the wheels 18 can extend through an opening or cut out 20 in or of the appropriate first 5, 6 and/or second flange or flanges 10, 11.

As shown in the embodiment shown in fig. 1 and 4 three wheels 18 can be provided, on axis 19 mounted to the second wall part 9. The wheels are 5 mounted such that they extend between the first and second wall parts 4, 9. A first wheel 18A, positioned as a middle one of the three wheels 18, is placed such that it can run on a first one 5 of the first flanges 5, 6, whereas the other two wheels 18B are placed such that they can run on the other 6 of the first flanges 5, 6, on the appropriate running surfaces 16. The axes 19 are therefore 10 placed on the corners of a triangle, for example a flat topped isosceles triangle or an asymmetric triangle, the base being formed between the axes 18B. The wheels 18 can have the same diameter D.

The first 5 of the first flanges 5, 6 can be an upper one of the flanges 5, 6. In this embodiment cut outs 20 are provided in both of the second flanges 15 10, 11 in order to allow the wheels 18 to extend through said cut outs 20 to run on the appropriate running surfaces 16 of the first flanges 5, 6. The two wheels 18B can be running on a lower first flange 5. The two wheels 18B can be situated near opposite ends of the second guide element 3.

As shown in the embodiment shown in fig. 2 and 5 three wheels 18 20 can be provided, on axes 19 mounted to the second wall part 9. The wheels 18 are mounted such that they extend between the first and second wall parts 4, 9. A first wheel 18A, positioned as a middle one of the three wheels 18, is placed such that it can run on a first one 5 of the first flanges 5, 6, whereas the other two wheels 18B are placed such that they can run on the other 6 of the 25 first flanges 5, 6, on the appropriate running surfaces 16. The first 5 of the first flanges 5, 6 can be an upper one of the flanges 5, 6. In this embodiment a cut outs 20 is provided in the upper, first second flange 10 in order to allow the wheel 18 to extend through said cut out 20 to run on the appropriate running surfaces 16 of the upper first flanges 5. The other two wheels 18B run on the 9 lower one 6 of the two first flanges. Obviously, upper and lower refers to the position shown in the drawing but can be inversed.

As shown in the embodiment shown in fig. 3 and 6 five wheels 18 can be provided, on axis 19 mounted to the second wall part 9. The wheels 18 5 are mounted such that they extend between the first and second wall parts 4, 9. Two first wheels 18A, positioned on a first row 21, are placed such that they can run on a first one 5 of the first flanges 5, 6, whereas the other three wheels 18B are placed in a second row 22, such that they can run on the other 6 of the first flanges 5, 6, on the appropriate running surfaces 16. The first 5 of the 10 first flanges 5, 6 can be an upper one of the flanges 5, 6.

In all of the embodiments shown any number of wheels can be used, depending on for example the load bearing capacity desired. As can be seen in fig. 4 - 6 and especially 8 the wheels 18 can have a peripheral surface 23 which can be substantially flat, at least to such extend that the peripheral surface 23 15 rests on two opposite sides in the grooves 14, 15, leaving an intermediate space 24 open. This can prevent problems with contamination of the running surfaces 16. Furthermore, by resting the peripheral surface 23 of the wheels 18 on two opposite sides in the grooves 14, 15, a better support can be provided during axial loads or torque on the wheels 18, as the wheel is closed in at two 20 points at the sides. In case the wheel 18 has, at a certain point on the peripheral surface 23 of the wheel 18, a radius different from the tip radius of the wheel 18, the wheel 18 can adjust itself by moving sideways in the grooves 14, 15, to find a new position, wherein the peripheral surface 23 rests again at two opposite sides of the grooves 14, 15.

25 The diameter D of the wheels 18 and the positioning thereof can be such that when the first and second guide elements 2, 3 are assembled to form the linear guide 1, the first flanges 5, 6 are forced slightly outward, elastically, by the wheels. This means that play between the first and second guide element 2, 3 can be substantially eliminated. This can be achieved by having 10 opposite sides of the or each first wheel and the or each second wheel being slightly larger than the distance between the running surfaces.

In embodiments, for example figure 6, the distance Wflange between the running surfaces 16 or at least the portions of the flanges 14, 15 on which 5 the wheels run can be between 0 and about 0.5 mm, more specifically between about 0 and 0.3 mm smaller than the distance Wwheels between opposite sides of the first and second wheels 18A, B. In embodiments the distance Wflange between the running surfaces 16 of the flanges 14, 15 on which the wheels run can be between 0 and 1%, more specifically between 0 and 0.65%smaller than 10 the distance Wwheels between opposite sides of the first and second wheels 18A, B. In exemplary embodiments the distance Wheels can be about 40.85 +/-0.05 mm, and the distance Wflanges between the running surfaces 16 can be about 40.72 +/- 0.08 mm. The distances Wwheels and Wflanges are measured at the points of contact of the wheels with the running surfaces 16. The 15 difference between Wwheels and Wflanges can be chosen such that the play is zero or negative and preferably less then zero, but not too large, such that any tension on the wheels and especially their running surfaces and/or axes 19 resulting from the negative play is kept within mechanically allowable limits.

20 In the embodiment of fig. 4 the wheels 18 are mounted on portions 25 extending from a main part of the second wall part 9, such that the position of the mounting of the axes 19 to the second wall part 9 is closer to a plane X extending perpendicular to the axes 19 through the peripheral surface of the wheel 18A, B, especially through the contact area between the wheel 18 and 25 the running surface 16 or between the two contact areas between the wheel 18 and the running surface 16. Thus the arm between the load born by the wheel 18 and the wall mounting position of the axis 19 is limited and, preferably, minimized.

In the embodiments shown in fig. 7A - D different auxiliary parts 30 and additions are shown, by way of example only. These embodiments are 11 shown corresponding mainly to fig. 1 and 4. However, similarly other embodiments can be provided with the same or similar auxiliary parts and provisions, such as but not limited to the embodiments of fig. 2 and 3.

In fig. 7 A a linear guide is shown, having five wheels 18, in two 5 rows 21, 22. The first guide element or profile 2 is provided with lips 24, 25, for example at or near opposite longitudinal ends thereof, for mounting the first profile to a mounting provision, such as but not limited to a frame, wall or the like. The lips 24, 25 can be formed as elements partly cut out of the wall part 4 and pressed out of the surface of said wall part 4, as is known as such from the 10 art, to form lips having a part extending substantially parallel to but spaced apart from the wall part 4. A first of the lips 24 can for example have an connection 26 to the wall 4 at an upper end, the other, second of the lips 25 at a side, such that mounting is made easy and secure.

In the embodiment of fig. 7B the second guide element 3 is provided, 15 at one longitudinal end or at opposite longitudinal ends, with one or more locking elements 27, formed in or as part of the second flanges 10, 11. The locking elements 27 can for example be material parts of the flanges being pushed inward from the general surface of the flanges 10, 11, and can for example have facing bent surfaces 28. At one or at opposite longitudinal ends 20 of the first guide element 2 one or more cooperating locking blocks 29 can be provided, for example adhered to the wall 4 or mounted on a lip bent from the wall 9. The or each locking block can be formed in a suitable way for moving under elastic deformation, over and/or in between one or more locking elements 27, such that the first guide element 2 can be locked in an end 25 position relative to the second guide element 3 or vice versa, in a known manner, by the locking block 29 and locking element or locking elements 27, from which end position the guide elements can be released by again moving the block 29 from the locking element or elements 27 cooperating therewith.

In fig. 7C the second guide element 3 is provided with lips 24, 25 30 similar to the lips 24, 25 as shown in and described with respect to fig. 7A. In 12 this embodiment the lips 24, 25 can be used for mounting the second guide element 3. Obviously the lips 24, 25 of the embodiments of fig. 7 A and 7C can be combined in one guide too.

In fig. 7D an embodiment is shown in which the second guide 5 element 3 is provided with a different type of mounting provisions 29. In this embodiment the mounting provisions 29 are shown as press nuts, pressed in an appropriate manner into the wall 9 of the guide element, for example in openings stamped therein. Alternatively the mounting provisions can be screw threads, bayonet means or the like, and can be provided at least partly by 10 deformation of the wall 9. Similar provisions can be provided in the other guide element 2. In this embodiment at or near opposite longitudinal ends of the second guide element 3 lips 30 are cut from the wall 9 and bent inward, into the space between the guide elements 2, 3 towards the first wall 4. At opposite longitudinal ends of the first guide element 2 brake blocks 31 are 15 provided, such that when the second guide element 3 is moved longitudinally relative to the first guide element 2, one of the lips 30 will move against one of the blocks 31, thus limiting the path of travel of the guide elements 2, 3 relative to each other and thus the extension and/or retraction distances of the linear guide.

20 In a further embodiment depicted in figure 9, a part of the flanges 5, 6 and/ or 10, 11 of at least one of the guide elements 2, 3 may be cut away, as to provide a space for further auxiliary means, for example for a spring-damper system 32 to be connected to the first guide element 2. A lip 30 and/or further engaging means 33 can be provided on the second guide element 3 to 25 be able to engage with the spring-damper system 32.Obviously all or some of the parts and provisions of the embodiments as disclosed can be combined in a single embodiment. Similarly all kinds of other such provisions can be provided in a guide 1, for example but not limited to locking, retraction and mounting provisions as known in the art. For example a guide can be provided 30 in a known manner with stops, nuts, studs, lances, dents, bridges and other 13 forms of stamped mounting or travel path defining and/or limiting provisions. In embodiments at least one of the guide elements 2, 3 can be provided with a locking handle, which can engage the other of the guide elements 3, 2, for locking them in at least one desired position, relative to each other, which can 5 be released by operating said arm. The arm can extend at least partly between the walls 4, 9 of the guide elements 2, 3.

At least one of the guide elements 2, 3, especially the second guide element 3, can be provided with brush elements, such as brushes, sliding blocks or the like, for during travel cleaning of a relevant part of the guide 10 tracks.

The guide elements 2, 3 of the present disclosure can have any suitable length and can be made easily in any size or form, using known techniques. The number of wheels can be chosen for example based on expected load and desired accuracy. Using wheels as bearing means or part 15 thereof has the advantage than a relatively long path of travel can be obtained with a relatively short overall length of the guide. Moreover play can be limited between the guide elements, and the relative position of the wheels to the guide elements 2, 3 is well defined.

In the embodiments specifically shown the axes of the wheels 18 are 20 spaced apart at regular, constant intervals. In embodiments of the disclosure the distances can vary, for example in the length direction of the guide elements 2, 3, which can be advantageous when the load on the linear guide will not be applied symmetrically. Since the wall parts 4, 9 are spaced apart, elements can be inserted between these walls, without unduly limiting the 25 path of travel of the guide elements relative to each other, especially at or near opposite longitudinal ends of the guide elements 2, 3.

By using guide elements which have at least a partly substantially C- or U shaped cross section over most or all of their length, as for example shown in fig. 4 - 6, wherein the flanges 5, 6 and 10, 11 of the guide elements 30 overlap each other at least partly and preferably substantially, the overall 14 width of the guide 1 can be limited, without unduly compromising the strength of the guide elements 2, 3 and thus of the guide 1.

In linear guides 1 of the present disclosure any combination is possible of profiles for the different guide elements 2, 3, such as but not limited 5 to differences in cross section, sizes, running surfaces and flanges, wall thickness, method of manufacturing and auxiliary elements, such as but not limited to lips, notches, indentations, cut outs, nuts and bolts, mounting brackets and the like.

The invention is by no means limited to the embodiments shown and 10 described herein specifically, by way of example. Many variations are possible within the scope of the claims and disclosure, including all combinations and permutations of embodiments and parts thereof as shown. In embodiments at least one of the first and second guide elements 2, 3 can have two or more substantially C- or U- shaped cross section parts, such that two or more second 15 or first guide elements 3, 2 respectively can be mounted in said C- or U-shaped cross section parts, for example above or next to each other, for example for allowing a longer path of travel, for allowing two or more movable objects to be moved with the linear guide and/or for allowing extension in two opposite directions. In such embodiments synchronisation means can be provided for 20 synchronising the movements of the different moving guide elements 2 and/or 3. One or more of the wheels or axes can be adjustable in position, in order to adjust for example for play between the guide elements.

These and many other variations are possible within the scope of the present disclosure.

25

Claims

A linear guide, comprising a first and second guide element and an intermediate support means, wherein the first guide element has a substantially C-shaped or U-shaped sectional section, comprising at least a first wall section and two first flanges, the second guide element being in a has a substantially C- or U-shaped cross-section, comprising at least one second wall portion and two second flanges, wherein the support means comprises at least three wheels, which are supported on shafts mounted on the second wall portion, at least one first of the 10 runs three wheels on one of the first flanges and at least two of the wheels run on the other of the first flanges.

2. Linear guide according to claim 1, wherein said first wheel extends through a cut-out in one of the second flanges and / or the at least two second wheels extend through a cut-out in the other of the two flanges.

The linear guide of claim 1 or 2, wherein at least one of the second flanges extends at least partially between the first flanges.

4. Linear guide according to claim 3, wherein both of the second flanges extend at least partially between the first flanges.

5. Linear guide as claimed in any of the foregoing claims, wherein the guide elements have coincident longitudinal directions, wherein the length of the second guide element is less than half the length of the first guide element, the second guide element preferably having a length that is substantially is equal to the distance between opposite sides of a first and last of the wheels, viewed in the longitudinal direction.

A linear guide according to any one of the preceding claims, wherein the carrier means comprises at least three wheels, preferably an odd number of wheels, wherein at least one of the axles of the wheels is closer to one of the flanges than at least two of the other shafts, wherein the two flanges on which the wheels run are forced outwards by the wheels, the shafts preferably having a fixed position.

7. Linear guide as claimed in any of the foregoing claims, wherein the first and second guide element have a comparable cross-section.

8. Linear guide as claimed in any of the foregoing claims, wherein the flanges on which the wheels run have a groove, the wheels running on the side faces of the grooves, such that a circumferential surface of the wheels is at least partially free from the lower part of the 15 relevant groove.

9. Linear guide as claimed in any of the foregoing claims, wherein at least one of the first and second guide elements is and preferably both are guide elements, provided with at least one mounting lip.

10. Linear guide as claimed in any of the foregoing claims, wherein at least one of the guide elements has at least one lip that is folded from the respective first or second wall portion in the direction of the relevant second or first wall portion of the other of the guide elements.

The linear guide of claim 10, wherein the at least one lip is a portion of a brake and / or locking system.

12. Linear guide as claimed in any of the foregoing claims, wherein the first and second guide elements are substantially made of sheet metal.

13. Linear guide as claimed in any of the foregoing claims, wherein the first and second guide element are formed by at least one of: extrusion, casting, punching, forging, folding, drawing, press-bench molds and / or roll-forming.

14. Linear guide according to any one of the preceding claims, wherein the wheels have a diameter substantially between the distance between the second flanges and the distance between the first flanges, the distance between the first flanges being substantially equal to or greater than the distance between the second flanges.

An apparatus comprising a linear guide according to any one of the preceding claims.

A method of forming a linear guide, wherein a first and second guide element is formed, the first guide element having a substantially C or U-shaped cross-section, comprising at least a first wall portion and two first flanges, the second guide element has a substantially C- or U-shaped cross-section, comprising at least one second wall portion and two flanges, wherein at least three wheels are mounted on shafts extending from the second wall portion or wherein at least three wheels are mounted on shafts at the second wall portion, wherein the second guide element is at least partially slid into the first guide element, such that at least one first of the three wheels runs on one of the first flanges and at least two of the wheels on the other of the first flanges run, preferably such that the first flanges are at least partially spaced apart honed by the wheels.