CA2249740A1

CA2249740A1 - Swivelling device

Info

Publication number: CA2249740A1
Application number: CA002249740A
Authority: CA
Inventors: Heidemaria Henrich; Alfred Henrich; Horst Rossbach
Original assignee: Individual
Current assignee: PATES TECHNOLOGY PATENTVERWERTUNGSGESELLSCHAFT fur SATELLITEN und MODERNE INFORMATIONSTECHNOLOGIEN MBH
Priority date: 1996-03-14
Filing date: 1996-03-14
Publication date: 1997-09-18
Also published as: CN1214113A; EP0883772A1; JP2000506956A; WO1997034104A1

Abstract

The invention concerns a swivelling device comprising: a base member; a swivel shaft (6) which, in operation, can rotate about a swivel axis; a drive; and gearing. The swivelling device operates particularly reliably when the drive comprises at least one actuator (4, 5) operated by pressurized fluid. The invention provides a low-maintenance drive which has high torque and retaining forces, of the type required for satellite antennae, for example.

Description

Positioning / Pivot Mechanism The present invention concerns a positioning / pivot mechanism having the characteristics of the superordinate concept as described in Claim 1.
The concerned positioning / pivot mechanisms find practical application, for example, as positioning / pivot mechanisms for radar or satellite antennas, as well as for positioning of cameras used in traffic monitoring and in security systems. The appropriate positioning drives are also used in industrial robots for axial drives. The drives used in the positioning / pivot mechanisms familiarin practice are normally electrical motors, and in particular servo motors, which are coupled via a gear work or directly to the positioning / pivot shaft.
When the conventional positioning / pivot mechanisms are used in an inclement environment load forces then affect the positioning / pivot mechanism, which impair the precision of the setting adjustment driven by the positioning / pivotmechanism. Moreover in the presence of impinging external forces the behavior ofthe positions already set using the electrical motor drives becomes problematical because the stability is not easily achieved. Finally, production of electrical motor drives with the required stability are very costly in terms of manufacturing technology.
It is therefore the purpose of the present invention to create a positioning /
pivot mechanism which can provide a high level of stability with good setting precision.
This purpose is accomplished by a positioning drive with the characteristics as described in Claim 1. Because the drive includes at least one actuator driven bya pressurized fluid, high drive forces can be produced. The respective stabilitythat can counteract the effects of weather conditions or other mechanical loads can be simply achieved by the use of a sealed (leak-free) closure of the fluid-driven actuator.
A play-free drive unit is particularly feasible if the drive is a belt drive.
The belt drive can be adjusted or set without play by the use of an appropriate bias coupling of the belt as a force transmission element. Uncomplicated and symmetrical control of two positioning directions results when the drive includes two simply-acting linear actuators. For a high degree of setting precision and a high degree of setting power or a high drive torque it is beneficial if the pressurized fluid is a hydraulic fluid. In this case it is --particularly in the case of employment the outdoors -- recommendable that the fluid is not mineral oil-based, but mineral oil free, manufactured particularly with a glycol-, glycoether- or polyalkylglycol-base. These types of hydraulic fluids are essentially water soluble, biodegradable, and less of a threat to the CA 02249740 l998-09-l4 .
097/34l04 -2- PCT/EP96/0l091 environment that the mineral oil based hydraulic fluids. Furthermore, in the case of the hydraulic fluids that are not manufactured using a mineral oil base, the difference in the viscosities in the hot and cold condition are essentially less, so that changes in the environmental temperature would have only a slight affect on the hydraulics.
Structurally simple relationships result when the drive includes two hydraulic cylinders which are in principle arranged parallel to one another. The hydrauliccouplings and connections of the hydraulic cylinders can then be arranged adjacent to each other. The effect of the hydraulic cylinders on the drives is easily achieved if the hydraulic cylinders have piston rods which are equipped at their free ends rotary mounted rollers. It is advantageous if the belt driveshave a flat belt, particularly a single-sided dentate toothed belt or a spline belt as their force transmission element. Toothed belts, particularly flat toothed belts, are particularly well suited for the present drive applications because on the one hand they can be continuously loaded and on the other hand allow slip-free grip because of the positive mechanical engagement into the positioning / pivot shaft. A splined belt can be used if a certain slippage canbe tolerated. A particularly low maintenance, space economical and play-free drive results if the force transmission element is a finite belt which is attached at least one free end to the base element of the positioning device. Ifin addition to the force transmission element wraps the positioning / pivot shaft by at least 180 degrees, a reliable engagement of the force transmission element on the positioning / pivot shaft is assured. This is particularly true if the toothed belt engages the positioning / pivot shaft with its dentition inan appropriate pattern and thereby prcduces a positive mechanical engagement of the positioning / pivot shaft; that is, in the direction of 'wrap' . The transformation of the linear movement of the hydraulic cylinder into a rolling movement with respect to the surface of the toothed belt is possible in a very simple way if the rollers of the hydraulic cylinders are rollers with a cylindrical or drum-shaped cross section and with a smooth surface, that lie against the side of the toothed belt facing away from the toothed side. Becausehere no dentition engages the toothed belt the specific loads of the toothed belt in the region of the rollers are kept to a minimum. In the case of the drum-shaped cross section of the rollers the middle sections of the toothed beltare loaded with higher forces than the edge areas. The unburdened edge areas therefore undergo less wear.
The inertia of the moving parts of the positioning device can be kept minimal ifthe drive is situated on the base element and essentially rests [on it] during operation. If, however, the drive is situated on the positioning / pivot shaft o 97/34104 -3 PCT/EP96/01091 and, when in operation, is tilted opposite the base element together with the positioning / pivot shaft, then additional drives with hydraulic connections can be provided on the positioning / pivot shaft in a simple manner; for example, for a second positioning axle.
The positioning device should allow at least one complete turn around the positioning axis so that the positioning range of the positioning / pivot shaftshould be at least 360 degrees. It is particularly advantageous if the positioning range of the positioning / pivot shaft is at least 44Q degrees.
Provisions can also be made that several complete ro.ations can be made.
In the case of applications in which the setting of the positioning device on a single plane is not sufficient, it is advantageous if the positioning / pivot shaft has a tilt mechanism whose tilt axis is situated at a right angle to the positioning axis. When doing is it is also advantageous to the tilt mechanism ifit too is fluid driven. A compact and reliable construction is achieved when thetilt mechanism is provided with fluid via the hydraulic lines associated with the positioning / pivot shaft. Here, too, it is advantageous if the fluid is a non-mineral-oil-based hydraulic fluid.
A simple tilt mechanism which makes possible a tilt range of over 90 degrees results when the tilt mechanism includes a hydraulic cylinder, preferably dual action, double walled, situated outside of the positioning axis on the positioning / pivot shaft. If the tilt mechanism furthermore includes a pole ormast that is at least partially hollow and which in its hollow sections enclosesthe hydraulic cylinder in its hollow section, the result is a compact and kinematically simple tilt mechanism which, in addition, is easy to protect against weather effects. A compact tilt mechanism is created in that the hydraulic cylinder on the one hand abuts the free end of the tilt mechanism andon the other hand, abuts the positioning / pivot shaft. Thus the hydraulic cylinder of the tilt mechanism can provide a large structural length and thus a large functional stroke. The connection of the hydraulic cylinder of the tilt mechanism with the hydraulic pump of the positioning device drives is created ina simple and reliable manner via a hydraulic interface or via hydraulic lines;
for example, with plug connectors. The cost of production of the positioning arekept to a minimum if the positioning drive and the tilt mechanism are operated by a common hydraulic pump. In this case the hydraulic pump is intermittently operated if it provided with a pressure accumulator. This measure has a favorable effect on the energy consumption of the positioning device. For high reliability and economical manufacture of the available positioning device it isadvantageous if the actuators of the positioning device and / or the tilt mechanism are operated by means of 2/2-way poppet valves, in particular of the construction type of the globe valve. In this case it serves to further simplifythe system if exclusively structurally identical valves are used. Play-free drive with high stability is attained if the hydraulic cylinder of the positioning drive and / or the tilt mechanism in operation are consistently hydraulically actuated under a minimum pressure of more than 10 bar, especially more than 10 bar.
The use of technically perfected, reliable components is possible if the hydraulic pump is essentially similar in construction, preferably identical structurally , to a hydraulic pump for motor vehicle anti-lock systems.
Furthermore, ball valves for the drive of the actuators, which also are used in anti-lock systems, can be used to advantage. These components are distinguished by their impressively long service life even under adverse conditions.
Of advantage is a positioning device as described in the invention as apositioning- and / or tilt mechanism for satellite antennas; For example, used in tracking of satellites in low orbits or picking up communications satellites in mobile operations (on ships and the like).
The positioning device as described in the invention can also be employed to advantage as a positioning and / or tilt mechanism for surveillance cameras.
Here the considerable setting precision and the high degree of stability is advantageous if cameras with long focal lengths are used. The positioning deviceallows on the basis of its play-free, fast drive that operates with a high torque, the addition tracking of such cameras if they are mounted on masts that may sway in the wind. ~y so doing the costs of construction for such masts can be reduced considerably because moorings or guy stabilization, etc. can be of a more simple design. Moreover, there are advantages if surveillance cameras themselves are exposed to the meteorological conditions.
Finally, through the high torque that can be attained and the food, play-free setting precision positioning devices as described in the invention can be used to advantage also as axis (axial drive) for production or manufacturing robots.
In the following an application example of the present invention is illustrated using the following drawings:
Figure 1 : a positioning device as described in the invention in a simplified illustration as viewed from above in the direction of the positioning axis.
Figure 2 : an electrical and hydraulic basic diagram (showing the underlying principles) for the drive of the positioning drive pursuant to Figure 1, and CA 02249740 l998-09-l4 097/34l04 -S- PCT/EP96/0l09l ~igure 3 : a positioning and tilt mechanism in a side view in cross section with three possible settings of the apparatus carrier.
In Figure 1 a positioning device as described in the invention is illustrated ina simplified drawing as viewed from above onto the positioning axis.
The positioning device includes a fixed socket (1), that carries the two fixed abutments or counter bearings (2) and (3). In addition the hydraulic cylinders (4) and (5) are likewise firmly mounted on the socket (1). A positioning / pivotshaft (6) is situated in the circular disk shaped socket (1) and is rotary mounted opposite the socket (1), whereby the positioning / pivot shaft (6) is perpendicular on the drawing in Figure 1.
The hydraulic cylinders (4) and (5) carry the piston rods (7) and (8) at the free ends of which the rollers (9) and (10) are mounted. The rollers (9) and (10) are opposite the piston rods (7) and (8) and are freely rotating, whereby the axis of rotation of the roller is similarly perpendicular to the drawing plane; thus, it runs parallel to the axis of rotation of the positioning / pivotshaft.
A flat belt (11) in the form of a finite flat belt is attached using an end piece (12) to the counter bearing (3); from that point it runs parallel to the piston rod (7) in the direction of the roller (9), hugs the roller (9) by approximately 180 ~ and courses from that point again essentially parallel to the piston rod (7) in the direction of the positioning / pivot shaft (6). Then the flat belt (11) hugs the positioning / pivot shaft (6) likewise by approximately 180 ~ and forms a straight section between the positioning / pivotshaft (6) and the roller (10); the straight section is arranged essentially parallel to the piston rod (8). The roller (10) is wrapped by the flat belt in asimilar fashion as the roller (9). On the side of the hydraulic cylinder (5) facing away from the positioning / pivot shaft (6) the second free end (13) of the flat belt (11) is fastened to the counter bearing.
In Figure 2 an electrical and hydraulic basic diagram for the drive of the positioning drive pursuant to Figure 1 is shown.
The two simple operating hydraulic cylinders (4) and (5) with their piston rods (7) and (8) are connected via the hydraulic lines (20) and (21) to the connections (A) and (B). A hydraulic unit (not shown) connected at input P feedsthe assembly with hydraulic fluid at a particular pressure. For this purpose thehydraulic apparatus is provided with a pump and a pressure accumulator. Magneticvalves [solenoid valves] (22) and (23) are installed between the input (P) and the connections (A) and (B)i the magnetic valves are of the spring loaded 2-way-CA 02249740 l998-09-l4 097/34104 -6- PCT/EP96/0l09l magnetic valve type. From connections (A) and (B) additional hydraulic lines (24) and (25) extend to a 3/3 way diverter valve (26). On the other side the 3/3way valve (26) is connected to a pressure limiting valve (27), which itself is connected to a runoff (T).
The magnetic valves (22) and (23) are governed via a control circuit (20) and (31) by an electronic triggering unit (32). The electrical actuator unit (32) receives and input signal (33) as a command variable and a control signal delivered from an encoder (35) as a control variable. The encoder (35) receives input signals via the input circuits (36) and (37) from path tracker or angular tracker which are connected to the piston rods (7) and (8).
In Figure 3 a lateral cross section illustrates a concrete layout example of a positioning device as described in the invention. The socket (1) is, as is shownin the top view in Figure 1, designed circular disk shaped with fastening feet (40). In this case the positioning drive is mounted on the socket (1) and is essentially enclosed by a hood (41). Between the hood (41) and the socket (1) there is a seal or insulator (42) which closes off the inside of the hood cover at least spray-proof. A base unit (43) is mounted stationary on the socket and carries the counter bearings ((2) and (3) - not shown in Figure 3 - and the hydraulic cylinders (4) and (5) - likewise not shown in Figure 3. The hydraulic cylinders (3) and (4) are hidden with their piston rods (7) and (8) behind rollers (9) and (10). Rollers (9) and (10) are wrapped on their visible frontal aspects by the flat belt (11), which runs left from the roller (9) towards the observer, then the roller (9) goes around and right from the roller (9) away from the observer and wraps a pinion sector (44) of the positioning / pivot shaft (9), whereby the flat belt (11) courses behind the pinion sector (44) as shown in the illustration according to Figure 3. Right of the pinion sector the flat belt (11) reappears, runs towards the observer vie the roller (10) and thenright of the roller (10) again away from the observer. Thus there results an approximate Q-shaped or meandering wrap around of the pinion sector (44).
Thereby the pinion sector (44) is provided with axis-parallel grooves (45) that are provided for the positive mechanical engagement of the dentition of the flatbelt present as a toothed belt.
Above the pinion sector (44) the positioning / pivot shaft (6) runs into a bearing block (46) which is firmly, preferably in one piece, connected to the base unit (43). The bearing block (46) contains the pinion sector (44) and is adjacent to the lower bearing (47) which is designed as a pin [needle] bearing.
On the end of the bearing block (46) situated opposite to the pin bearing (48) aball bearing ~48) is provided for the bearing of the positioning / pivot shaft (6). Above and external to the ball bearing (48) a surrounding channel (49) that CA 02249740 l998-09-l4 097/34l04 -7- PCT/EP96/0l091 when in operation can receive a spirally wound signal cable, for example for thesignal circuit of a satellite antenna. This wound spiral can "breath" like the balancing spiral of a clock on rotation of the positioning / pivot shaft (6) and thus allows the passage of a signal circuit from the turning portion to the stationary position of the positioning device.
On the face side of the positioning / pivot shaft (6), in Figure 3 above the ball bearing (48), there is a head [cap] piece ~50) that is firmly screwed to the front face side of the positioning / pivot shaft (6) and covers the bearingblock (46). Between the bearings (47) and (4a) and in the bearing block (46) numerous ringlike, circumferential grooves (51) are tooled in which accomodate seal rings. The seal rings (not shown) are arranged in layers on the positioning/ pivot shaft (6)surface to be permanently able to slide, for example using PTFE. Two smaller grooves (52) with a free cross section communicate with channels (53) that are installed in the positioning / pivot shaft (6). The grooves (52) are connected to hydraulic valves (not shown in the illustration) that are associated with the base unit (43) and allow, on actuation, influx of hydraulic fluid into the grooves (52) so that the pressurized hydraulic fluid can enter into the channels (53) and then be caught in the area of the head [cap] piece (50). Inside the hood (41) and in Figure 3 an electrical'y driven hydraulic pump assembly (55) is situated behind the positioning / pivot shaft (6); the pump conveys hydraulic fluid for the operation of the positioning and tilt mechanism into a pressure accumulator (56). The hydraulic fluid, which is under pressure, can then be removed from the pressure accumulator and used.
On the top of the positioning and tilt mechanism; that is, above the hood (41), there is a hydraulically tiltable mast (60) that is shown in three positions L, M, and R. The hollow mast (60) encloses a double action hydraulic cylinder (61) which for the most part is situated inside the mast (60). The mast (60) and the hydraulic cylinder (61) are each over a positioning bearing (62) and (3) situated at the head piece (50) and connected tiltable with it. The actuation ofthe hydraulic cylinder (61) is accomplished by means of hydraulic fluid from thechannels (61) and is conducted to the hydraulic cylinder (61) via hose lines (not shown). In the case of a completely extended hydraulic cylinder (61) the mast assumes the "L" position; in the completely retracted hydraulic cylinder (61) the mast assumes the "R" position and in a middle setting the "M" position is assumed. A sleeve (65) surrounds the unsheathed potions of the mast (60) and,together with the socket (1) and the hood (41), permits a closure vis-a-vis the outside at least against dust and water.
In practice the mast (60) would carry at its top, for example, a satellite antenna for positioning.

09~/34104 -8- PCT/EP96/01091 The positioning and tilt mechanism described up to this point and which operatesin accordance with this idealized design example functions in practice as follows:
The positioning and tilt mechanism is mounted at its base, for example, on the bridge of a ship and carries at the top of its mast (60) a satellite antenna fortelecommunications connections.
The field strength of the satellite goes as a command or reference value (33) into the electronic and hydraulic circuitry in accordance with Figure 2. There the selection unit (32), that must open the valves (22) or (23), picks up in order to bring the hydraulic cylinders (4) or (5) (which operate as linear actuators) into the appropriate position. The signal so produced is sent either via the control circuit (30) or via the control circuit (31) to one of the magnetic valves (22) or (23), whereupon the latter conduct the hydraulic fluid flow from the inflow "P" to the feed points "A" or "B". In the event the controlsignal is sent to the control circuit (30) and magnetic valve (22) opens, hydraulic fluid from the inflow "P" flows to feed point "A" and from there via the line (20) into the hydraulic cylinder (4) whose piston rod (7) extends. It can be seen in Figure l that when this occurs the roller (9) is pressed against the toothed belt (ll) and shifts it, as shown in Figure l, upward. The section of the toothed belt (ll) required for this to happen is pulled around the positioning / pivot shaft (6) which turns in a clockwise direction while in response the piston rod (8) is pushed into the hydraulic cylinder over the roller (lO). In Figure 2 it can again be seen that in the case of the retracted piston rod (8) the hydraulic fluid is pressed out of the hydraulic cylinder (5) and flows to the feed point "B".
Since the hydraulic valve 23 is closed, the hydraulic line (24) opens up the hydraulically regulated 3/3 reversal valve (26) in such a fashion that the hydraulic line (25) is connected with the pressure limiting valve (27) by way ofwhich the hydraulic fluid can make its way to outflow "T". When doing this the pressure limiting valve (27) malntains a certain minimum pressure in the hydraulic system the end result of which is that the toothed belt (ll) is stressed by way of the hydraulic cylinders (4) and (5).
The position calculated by the selector or Localizer unit (32) of the satellite antenna is forwarded to the encoder (35) via angle and path locators and their input signals (36), (37) and the encoder communicates to the Localizer /
selector unit the actual position of the linear actuator (4). If the desired position is reached then the magnetic valve (22) is closed so that the minimum pressure programmed by the pressure limiting valve (27) is maintained in the CA 02249740 l998-09-l4 097/34l04 -9- PCT/EP96/0l091 system and the positioning and tilt mechanism is thus hydraulically biased or prestressed. Should the regulatory circuit have to regulate in the opposite direction then the magnetic valve (23) is opened, the hydraulic fluid flows frominflow "P" to feed point "B" and from that point into the hydraulic cylinder (5)whose piston rod (8) extends. Simultaneously the piston rod (7) of the hydrauliccylinder (4) is pushed in. The hydraulic fluid which is forced out of hydraulic piston (4) flows via the line (20) to the feed point "A" and from that point is connected with the pressure limiting valve (27) via the line (24). The excess hydraulic fluid flows from there to outflow "T". On conclusion of the positioning movement the magnetic valve (23) closes so that the system again is maintained under the minimum pressure. A reflux of hydraulic fluid from the system to the inflow can occur if the pressure in the pressure accumulator fallsbelow the minimum pressure of the system and the closure force of the magnetic valves (22) and (23) is not reached in order to prevent it from happening. If said reflux is to be prevented check valves can be installed between their magnetic valves (22) and (23) and the associated feed points "A" and "B", respectively.
As can be seen in Figure 1 the rotational movement of the positioning / pivot shaft (6) around its axis of rotation is effected by the advance of one of the respective hydraulic cylinders (4) or (5), whereby the other respective hydraulic cylinder, because of the reactionary force, is compressed. In this particular design form the hydraulic cylinders (4) and (5) do not require any particularly costly bearing [mounting] for their piston rods (7) and (8), since the rods are held approximately in the middle between the counter-bearings (2) and (3) and the pivot shaft (6).
The cross sectional drawing in Figure 3 illustrates the relative arrangement of the various components which, as far as the positioning or pivot drive is concerned, for the most part can be situated in the base element (43). Thus the base element contains the counter-bearings (2) and (3) for the free ends (12) and (13) of the flat belt. Furthermore, the hydraulic cylinders (4) and (5) are worked into the base element or are screwed onto it. The hydraulic lines which connect the hydraulic assembly (55) and the pressure accumulator (56), the respective magnetic valves (22) and (23) and the 3/3 reversal valves (26) and the pressure limiting valve (27) with the hydraulic cylinders (4) and (5) are worked into the base element (43) as channels or passages and the respective hydraulic valves are installed in the respective passages using simply springs and seal rings. This arrangement is easy to maintain, compact, and very reliablein operation.

CA 02249740 l998-09-l4 097/34l04 lo- PCT/EP96/0109l Precisely for use in inclement weather conditions the compact construction is advantageous in which the socket (1), the hood (41) and the sleeve (65) protect all components against the effects of weather. The result of this weather resistance is a high degree of operational reliability. This reliability is evenfurther increased in that the globe valves of the antilock systems conventional in the automobile construction are used as magnetic valves. Also the hydraulic assembly (55), (56) can be structurally identical to the hydraulic pumps of antilock systems. These components from motor vehicle design are distinguished by their well-known minimum probabilities of failure and breakdown.
In the case of use of the positioning / pivot and tilt mechanisms so far described, it can be presumed that hydraulic fluid manufactured from a non-mineral oil base, such as, for instance, brake fluid as used in the motor vehicle sector, can be used. These hydraulic fluids have, particularly in marineapplications, the advantage that they are less of an environmental threat than mineral oil based hydraulic fluids and, furthermore, are less sensitive to extreme temperatures, impingement of water, and have high corrosion resistance.
In a similar way the positioning / pivot and tilt mechanisms as described in theinvention can also be equipped with pivot drives thal are not equipped with two unidirectionally operating hydraulic cylinders as linear actuators, but with only one double-action hydraulic cyllnder. In this case the result is not just simply the opportunity to stress the entire belt drive hydraulically and thus achieve stability. In addition, the positioning / pivot drive as shown in Figure1 is completely symmetrical in both of its pivotal directions, whereas a double-action hydraulic cylinder produces in the two directions slightly different forces dependent on the hydraulic pressure applied.
Finally, the pinion sector of the positioning / pivot shaft (6) can also be further simplified in that grooves for toothed belts are provided that do not run parallel to the axis, but circumferential grooves with trapezoidal cross section are tooled that then make possible the use of a spline belt as a flat belt (11). This configuration allows a more economical manufacture of the positioning / pivot shaft (6), but in exchange a certain slippage of the flat belt (11) vis-a-vis the positioning / pivot shaft (6) must be compensated.
The head piece (50) can also carry an additional positioning / pivot drive or other assemblies in place of the tilt mechanism shown in the figures; the choicedepends on the application.
Furthermore, the base element (43) can be equipped with speed receivers so that intrinsic movements of the socket can be picked up and can be compensated immediately in the device.

Claims

1. A positioning / pivot mechanism with a base element (43), with a positioning / pivot shaft (6)rotating around a pivot axis [when] in operation, and with a drive and transmission, characterized by the fact that the drive includes at least one actuator (4,5) operated with a pressurized fluid.

2. A positioning / pivot mechanism in accordance with Claim 1, characterized by the fact that the transmission is a belt drive transmission (9, 10, 11, 44).

3. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the drive includes two elementally functioning linear actuators (4, 5).

4. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the fluid is preferentially not a mineral oil based hydraulic fluid, but particularly glycol, glycolether, and or polyalkylglycol based.

5. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the drive includes two hydraulic cylinders (4, 5) that are arranged essentially parallel to each other.

6. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the hydraulic cylinders (4, 5) have piston rods (7, 8) that are provided with rotary rollers (9, 10) at their free ends (12, 13).

7. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the belt drive is a flat belt (11), in particular a toothed belt (11) with dentition on only one side or a spline belt as the force transmission element.

8. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the force transmission element is a finite belt (11) that is fastened at at least one free end to the base element (43) of the positioning / pivoting mechanism.

9. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the force transmission element (11) surrounds the positioning / pivot shaft by at least 180 °.

10. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the toothed belt (11) engages the positioning / pivot shaft (6) with its dentition in a suitable pattern (45).

11. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the rollers (9, 10) of the hydraulic cylinder (4, 5) are rollers with a cylindrical or drum shaped cross section and a smooth surface that lie on the side of the toothed belt (11) away from the toothed side.

12. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the drive (4, 5) is attributed to the base element (43) and in operation essentially rests.

13. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the drive (4, 5) is attributed to the positioning / pivot shaft (6) and in operation is positioned opposite the base element (43).

14. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the positioning / pivot freedom range of the positioning / pivot shaft (6) is at least 360 °.

15. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the positioning / pivot freedom range of the positioning / pivot shaft (6) is at least 440 °.

16. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the positioning / pivot shaft (6) carries a tilt mechanism (60, 61) whose tilt axis is approximately perpendicular to the pivot axis.

17. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the tilt mechanism (60, 61) is fluid (hydraulic) driven.

18. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the tilt mechanism (60, 61) is supplied with fluid by means of the hydraulic lines (53) attributed to the positioning / pivot shaft (6).

19. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the tilt mechanism (60, 61) includes a hydraulic cylinder (61) coupled external to the pivot axis and preferably double-acting and / or double walled.

20. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the tilt mechanism (60, 61) includes an at least partially hollow mast (60) whereby the hydraulic cylinder (61) of the tilt mechanism (60, 61) is situated essentially within the hollow mast section.

21. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the hydraulic cylinder (61) on the one side is coupled at its free end to the tilt mechanism (60, 61) and on the other end to the positioning / pivot shaft (6).

22. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the hydraulic cylinder (61) of the tilt mechanism (60, 61) is connected to a hydraulic pump via a hydraulic interface / coupling.

23. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the hydraulic cylinder of the tilt mechanism is connected via hydraulic lines to a hydraulic pump (55).

24. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the positioning / pivot drive (45) and the tilt mechanism (60, 61) are operated by a common hydraulic pump (55)

25. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the a pressure accumulator (56) is assigned to the hydraulic pump (55).

26. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the actuators (4, 5, 6) of the positioning / pivot mechanism are controlled by means of 2/2 way valves (22, 23), in particular ball valves.

27. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that exclusively structurally identical 2/2 way valves (22, 23) are intended for the purpose of triggering the actuators (4, 5, 6).

28. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the hydraulic cylinders (4, 5, 6) of the positioning / pivot drive and / or of the tilt mechanism while in operation are constantly under a minimum pressure of over 10 bar, preferably more than 20 bar hydraulic stress.

29. A positioning / pivot mechanism in accordance with one of the foregoing Claims, characterized by the fact that the hydraulic pump (55) is essentially structurally similar, preferably identical to a hydraulic pump for motor vehicle antilock systems.

30. The use of a positioning / pivot mechanism in accordance with one of the foregoing Claims as a positioning / pivot and / or tilt mechanism for satellite antennas.

31. The use of a positioning / pivot mechanism in accordance with one of the foregoing Claims as a positioning / pivot and / or tilt mechanism for surveillance cameras.

32. The use of a positioning / pivot mechanism in accordance with one of the foregoing Claims as an axial drive for robots.