EP0950597B1 - Guiding system with a carriage guided on a rail - Google Patents

Description

Technical field

The invention relates to a carriage for a guide system with one with guide surfaces and with a toothed rail. The carriage has a drive gear, which in one Force application point engages in the toothing of the rail, and further guide elements that in corresponding support points on the laterally arranged guide surfaces of the rail are, wherein the drive gear and at least a first of the guide elements in constant Are spaced from each other and are arranged so that one through the force application point on the one hand and the point of contact of said first guide element on the first guide surface on the other hand, the straight line defined is always perpendicular to the current direction of travel. Further refers the invention on a guide system with such a carriage and on a rail for Carriage.

State of the art

Conveyor systems that can move to specified positions exactly are e.g. in the automated Manufacturing needed. With such a conveyor system, the workpieces can be removed from a processing station transported to a next one and automatically handed over there.

Systems are known in which the individual transport carriages with rollers on a metal rail to run. The rollers are typically driven by electric motors. The roller drive enables A great deal of freedom in determining the course of the rail, since there are no problems with routes can be constructed with different radii of curvature. However, are roller drives not exactly in position (because of the slip). Accordingly, the precision can only be achieved by additional position sensors and associated control circuits can be achieved. In a plant with a plurality of carriages, block controls must also be used for safety reasons be provided.

It is known that position accuracy e.g. can be achieved with gear and spindle drives can. Such drives come e.g. in machines with precisely movable processing units (Milling machine, drill, etc.). A typical application example is a bogie or Rotary table of an automatic assembly machine. By the number of revolutions of the pinion or the driving The gear is precisely determined.

The known gear drives are only for the execution of either exclusively linear or only suitable for rotating movements.

The German utility model G 92 14 738 (Bleichert) shows a conveyor system with a guide rail and a rack whose teeth are aligned horizontally. In a first embodiment (Fig. 1), the trolley has a drive gear, which is coaxial to the foremost transverse guide roller is stored. The roller system is in a box-shaped guide rail that is open at the top guided and the rack is located laterally above the guide rail. In another Embodiment (Fig. 3), the guide rail is a simple carrier, on the outside the roller system is guided. The rack is attached laterally below the guide rail and the geometric axis of the gear runs through the center of the guide rail. The The toothing of the rack runs in each case plane-parallel to the plane-parallel transverse guideways the guide rail.

Another such conveyor system is known from DE 30 31 355 A1 (Bleichert).

FR 2 336 287 is concerned with a passenger transport system with gear drive. The guide rail has side guide surfaces for corresponding guide rollers of the carriage. The Gearing points vertically downwards. This system is not suitable for curves.

Presentation of the invention

The object of the invention is a carriage, a guide system, and a rail of the types mentioned indicate which positional accuracy and largely free lines combine.

The solution to the problem is defined by the features of claims 1, 7 and 16.

According to the invention the carriage has at least one chassis, the pivot axis of which Force application point of the drive gear runs.

A toothed rack is formed on the rail such that the dividing line of the toothing unites has a predefined constant distance from at least one lateral guide surface. The carriage has a guide element, which on the lateral guide surface mentioned in a support point is guided, and a drive gear, which engages in a force application point in the rack. Drive gear and guide element are arranged so that by the force application point and The point of contact defined is always perpendicular to the current direction of travel. The The current direction of travel is defined by the tangents to the dividing line.

Due to the geometrical design of the toothing according to the invention, a gear-driven guide system with largely any rail guide can be realized. Not only can in addition to straight sections - both left and right turns, but Different curve radii can also be integrated in the same system.

The dividing line runs through a perpendicular bisector of the cross section of the Guide rail. As leadership elements usually used leadership roles. But sliding elements are also possible.

A carriage according to the invention has at least one, but preferably two chassis. This are designed so that when the direction changes, the axis of rotation or swivel of the chassis runs through the dividing line of the gearing. The pivot axis goes through the Force application point and is parallel to an axis of rotation of the drive gear. (Has the carriage only a single chassis, then the center of gravity of the carriage should be on the above Swivel axis.) This ensures that the driving force (acceleration or Braking force) generates no reaction torque on the carriage (or its chassis).

According to a particularly preferred embodiment, the chassis has a three-point guide. This means that the lateral guidance or control of the direction is in principle taken over by three roles. Two run on one guide surface and one on the other just a role. The three points of the side guide form an isosceles triangle with an opening angle of e.g. 30 ° to 40 °.

Two of the three rollers are advantageously sprung. It is the one that are arranged on the same side and consequently run on the same guide surface. There can also be more than three guide rollers (the number of Suspension must be adjusted accordingly). Only two guide rollers become symmetrical provided to the swivel axis of the chassis, stabilization can become a problem (Vibrations, rolling movements).

The preferred version of the three-point guide allows one for any curve radius geometrically exact tooth mesh.

The weight of the carriage is preferably carried by separate support rollers. This do not need to be sprung. The rail has e.g. a substantially flat rectangular one Cross section, the outer narrow sides of the guide surfaces and the top and bottom surfaces in the edge area the running surfaces for the support rollers form. Depending on whether the carriages are standing on the rail or hanging on it, the rack is formed on the upper or lower broad side of the rail.

The guide rail and the rack must be manufactured with high precision. The two parts can be manufactured individually and then connected (screwed, welded). So that the geometry of the toothing in the curves is correct, you can two identical straight racks with the gears interlocked and then be bent together into the desired radius. But it is also possible that the guide rail and rack are milled directly from a single workpiece. The guide rail is advantageously attached to a carrier, which has the required has static resilience, so that the precision-made part of the rail system dimensions and weight can be kept to a minimum. The carrier can be an ordinary double T-beam without special precision criteria. The Rail is preferably essentially along its entire length (e.g. by regular spaced fasteners) attached to the carrier, so that their inherent stability is guaranteed. Finally, a conductor rail can also be attached to the carrier.

The guide system according to the invention can be modular. That means it different rail pieces (straight, left-curved, right-curved) are provided, which the user creates according to his needs individual transport system can be put together. In combination with Turnouts, crossings or even lift stations result in a wide range of Possibilities.

From the following detailed description and the entirety of the claims there are further advantageous embodiments and combinations of features of the invention.

Brief description of the drawings

Fig. 1

Eine schematische perspektivische Darstellung der Geometrie der erfindungsgemässen Schiene;

Fig. 2

eine schematische Darstellung der Führung eines Fahrgestells auf einer gekrümmten Schiene in der Draufsicht;

Fig. 3

eine schematische Darstellung der in Fig. 2 gezeigten Anordung im Querschnitt.

The drawings used to explain the exemplary embodiment show:

Fig. 1

A schematic perspective representation of the geometry of the rail according to the invention;

Fig. 2

a schematic representation of the guidance of a chassis on a curved rail in plan view;

Fig. 3

is a schematic representation of the arrangement shown in Fig. 2 in cross section.

In principle, the same parts are provided with the same reference symbols in the figures.

Ways of Carrying Out the Invention

Fig. 1 shows schematically the principle of the invention. A rail 1 is for example on Foot of a double-T beam 10 attached. The rail 1 has the shape of a plate or a strip or ribbon-shaped flat element and consists of a high quality Steel. The narrow sides 2.1, 2.2 serve as lateral guide surfaces, the lower and upper edge surfaces 3.1, 3.3 or 3.2, 3.4 as running surfaces.

On the lower side of the rail 1 is in the area between the edge surfaces 3.1 and 3.3 a rack 4 attached. Their toothing 5 is according to a preferred one Embodiment arranged such that its dividing line 6 exactly in the middle of the Rail 1 runs.

The following should be noted in detail: In cross section with respect to the longitudinal direction of the When viewed on rail 1, the division line 6 lies (or its point of intersection through the cross-sectional plane) on the perpendicular 7 of the (in the present example) mirror-symmetrical trained rail 1. In other words: Assuming that the two Narrow sides 2.1, 2.2 define two parallel planes, and one defines exactly in the In the middle between these two imaginary levels there is a third level Division line 6 of the toothing 5 in this third level.

The axis of rotation of the drive gear is parallel to the perpendicular 7 (i.e. in Fig. 1 vertically and not horizontally). Correspondingly, the toothing 5 shows in horizontal Direction.

The geometric orientation can also be described as follows: The toothing 5 can be assigned a foot line 9 and a head line 8. (Is the rack 4 curved; can instead of a foot line 9 from a foot circle instead of one Head line 8 from a head circle and instead of a dividing line 6 from one Pitch circle or pitch circle can be spoken.) The foot line 9 and the head line 8 lie on two different sides of the perpendicular bisector 7. Basically comes it does not depend on whether the foot line 9 on the left with respect to the perpendicular 7 (i.e. on the side facing the narrow side 2.1) or on the right, i.e. if she Toothing to the left or to the right shows.

2 and 3 show how a chassis 11 is guided by the rail 1 according to the invention becomes. 2, the rail 1 is viewed from above. The carriage 21 is located below the rail 1 and is e.g. on two identical chassis hinged. Fig. 3 shows the same construction in cross section.

In the sense of the particularly preferred embodiment of the invention, there are three guide rollers 15.1 to 15.3 intended for lateral guidance. The guide rollers 15.1 and 15.2 are mounted on a first side wall 16 of the chassis 11. Two suspensions 18.1, 18.2 press the two guide rollers 15.1 and 15.2 against the narrow side 2.2. The third Guide roller 15.3 is on an opposite side wall 17 of the chassis 11 unsprung.

The distance between the two side walls 16, 17 is slightly larger than the width of the rail 1, so that the chassis can grip around the rail 1 in a U-shape. Furthermore, the present Example the side walls 16, 17 towards the narrow sides 2.1, 2.2 of the rail 1 convexly curved. According to the smallest radii of curvature in the system the rail they run easily from the center of the chassis to the outside apart.

The axes of rotation of the three guide rollers 15.1 to 15.3 form the corners of an isosceles Triangle. (The two same legs of the triangle are through the connecting lines the axes of the guide rollers 15.1 and 15.3 on the one hand and 15.2 and 15.3 the opening angle of the triangle is preferably in the range between 30 ° and 40 °.

If the opening angle is too small, the stability of the guide suffers. That means it can Pendulum or roll movements come about a vertical axis. Is the named On the other hand, if the angle is too large, the spring-loaded guide rollers 15.1 and 15.2 must be unnecessary have large spring travel (especially when cornering relatively tightly) should be or if there are very different radii of curvature).

One of the two guide rollers 15.1 and 15.2 is always leading and one trailing. For example, when changing from a straight section to a curved section Suspension 18.1, 18.2 for smooth initiation of the change of direction or chassis swivel movement.

The point of contact 24 of the guide roller 15.3 on the narrow side 2.1 is in relation to the Chassis 11 clearly defined because the guide roller 15.3 mentioned is neither resilient stored itself is elastic. The distance between gear 13 and guide roller 15.3 is constant. According to the invention, the force application point 14 and Support point 24 defined direction always perpendicular to the current direction of travel. The latter is defined by the tangent to the division line in the force application point 14.

An important aspect of the invention is that the (in Fig. 2 perpendicular to Swing axis (see reference numeral 22 in FIG. 3) of the chassis standing in the plane of the drawing 11 runs exactly through the force application point 14 of the dividing line 6 of the toothing 5. This is regardless of whether the rail 1 is straight or (with some radius to the left or right) is curved.

A carriage 21 typically has two chassis. One has one Electric drive 12, the gear 13 in the toothing 5 of the rack 4th intervenes. The dividing line 6 has a constant distance from the along the rail 1 Narrow side 2.1, which guides the guide roller 15.3. The rack 4 is located between the gear 13 and the rigid guide roller 15.3.

The position of the carriage 21 can be accurate with a numerically controlled motor to be controlled. Current and control signals can be used with a pantograph of one e.g. busbar 23 attached to the carrier 10 can be tapped (cf. FIG. 3).

Characterized in that the pivot axis 22 through the force application point (contact point between the toothing 5 and the gear 13 or point of contact of the dividing line 6 with the Rolling circle or pitch circle 20 of the gear 13) runs when starting or Braking no torque exerted on the chassis. The ones mentioned above undesired pendulum or wobble movements cannot be stimulated. Furthermore, a geometrically precise tooth meshing is guaranteed.

In addition to the three guide rollers 15.1 to 15.3, 16 and 17 are on each side wall four castors are provided. In Fig. 2 the four are on the top side i.e. on the edge surfaces 3.2 and 3.4 running rollers 19.1 to 19.4. The pairs of rollers 19.1 / 19.2 and 19.3 / 19.4 are mounted at a small mutual distance. (The In the present example, two rollers 19.1 and 19.2 are accommodated by the guide rollers 15.1, 15.2 limited length section.) The axis of the guide roller 15.3 is located in the middle between the rollers 19.3 and 19.4.

Symmetrical to the four upper rollers 19.1 to 19.4 are four more rollers provided on the lower side (in Fig. 3 only two of these four further rollers are shown, cf. Reference numbers 19.5 and 19.6). The chassis 11 can because of this Do not tilt the roller assembly.

The described embodiment can be carried out in many ways within the scope of the invention as defined in the claims be modified. The chassis can also be arranged standing instead of hanging become. The rail can also be inclined.

It is not mandatory between the guide rollers and the rollers or support rollers be a functional separation. That means you can also choose a construction in which certain roles both for guiding the car and for support serve the weight. The rail can be symmetrical, for example, on the lateral edges beveled. It is even conceivable that the cross section of the rail is not symmetrical is.

The rail usually runs on one level. That means the radii of curvature lie in the plane defined by the strip shape of the rail. But it’s not out of the question that the direction of the rail by slow change over a long distance is led out of this level ("flat ramp").

Of course, it is not imperative that the rail be supported by a double-T beam or the like is supported. It can also be self-supporting.

Depending on the application, the guide rollers can be hard or elastic. In certain circumstances an elastic tire can make resilient storage unnecessary (e.g. if the Radii of curvature of the rail are very large).

In summary, it can be stated that the invention is a guidance system has been created, which can be positioned precisely with any lines enabled with relatively little control engineering effort. In addition, the invention versatile, be it on a larger machine with a computer-controlled one Workpiece processing or as a transport system in manufacturing plants or even in Amusement parks.

Claims (18)

1. Carriage (21) for a guiding system with a rail (1) provided with guide surfaces and with a toothing (5),

   a) which has a drive gear (13) which can engage in a point of application of force (14) in the toothing (5) of the rail (1), and

   b) which further has guide elements (15.1, 15.2) which can be guided in corresponding points of support on the laterally disposed guide surfaces (2.1, 2.2) of the rail (1),

   c) wherein the drive gear (13) and at least a first one of the guide elements (15.1, 15.2) are at a constant spacing relative to one another and

   d) are so disposed that a straight line defined by the point of application of force on the one hand and the point of support (24) of the said first guide element (15.1, 15.2) on the first guide surface on the other hand is always perpendicular to the current direction of travel,
   characterised in that

   e) the carriage has at least one chassis (11) of which the swivel axis (22) extending parallel to an axis of rotation of the drive gear (13) extends through the point of application of force (14) of the drive gear (13).
2. Carriage as claimed in Claim 1, characterised in that the swivel axis (14) of the chassis (11) extends through the centre of gravity of the carriage (21) or of the chassis (11) and the point of application of force.
3. Carriage as claimed in one of Claims 1 or 2, characterised in that the guide elements (15.1 to 15.3) form a three-point guide.
4. Carriage as claimed in Claim 3, characterised in that two guide elements (15.1, 15.2) which can be guided on the same guide surface are spring-mounted.
5. Carriage as claimed in one of Claims 1 to 4, characterised in that the said first guide element (15.3) is unsprung in order to be at a constant spacing relative to the drive gear (13).
6. Carriage as claimed in one of Claims 1 to 5, characterised in that tread rollers (19.1 to 19.4) are provided which can engage on the rail (1) from above and below.
7. Guiding system, comprising a carriage (21) as claimed in Claim 1 as well as a rail (1) provided with lateral guide surfaces (2.1, 2.2).

   a) wherein a dividing line (6) belonging to the toothing (5) has a pre-defined constant spacing relative to at least a first of the lateral guide surfaces (2.1, 2.2),

   b) wherein the toothing (5) is directed laterally towards the left or towards the right with respect to the guide surfaces (2.1, 2.1), and

   c) wherein the dividing line (6) of the toothing (5) is disposed in the region between the guide surfaces (2.1, 2.2).
8. Guiding system as claimed in Claim 7, characterised in that the dividing line (6) of the toothing is disposed in the middle of the rail (1).
9. Guiding system as claimed in Claim 7 or 8, characterised in that the toothing (5) is formed by a rack (4).
10. Guiding system as claimed in one of Claims 7 to 9, characterised in that the carriage has at least one chassis (11) of which the swivel axis (14) extends through the centre of gravity of the carriage (21) or of the chassis (11) and the point of application of force.
11. Guiding system as claimed in one of Claims 7 to 10, characterised in that the guide elements (15.1 to 15.3) form a three-point guide.
12. Guiding system as claimed in Claim 11, characterised in that two guide elements (15.1, 15.2) which can be guided on the same guide surface are spring-mounted.
13. Guiding system as claimed in one of Claims 7 to 12, characterised in that tread rollers (19.1 to 19.4) are provided which can engage on the rail (1) from above and below.
14. Guiding system as claimed in one of Claims 7 to 13, characterised in that the rail (1) is basically constructed in strip form and is fixed on a carrier (10) which ensures the stability or carrying capacity.
15. Guiding system as claimed in one of Claims 7 to 14, characterised in that the rail (1) has not only straight sections but also sections which are curved to the left and right.
16. Rail (1) for a guiding system as claimed in Claim 7, which has two lateral guide surfaces (2.1, 2.2) and a toothing (5), wherein the toothing (5) has a pre-defined constant spacing relative to at least one of the lateral guide surfaces (2.1, 2.2) and wherein the toothing (5) is directed laterally towards the left or towards the right with respect to the said guide surfaces (2.1, 2.1), characterised in that a dividing line (6) associated with the toothing (5) extends through a midperpendicular (7) of the cross-section of the rail (1).
17. Rail as claimed in Claim 16, characterised in that it is basically constructed in strip form and is fixed on a carrier (10) which ensures the stability or carrying capacity.
18. Rail as claimed in one of Claims 16 or 17, characterised in that it has not only straight sections but also sections which are curved to the left and right.

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