NL2013841B1 - Hydraulic lifting unit for a simulator and a simulator with such a lifting unit. - Google Patents

Abstract

A hydraulic lifting unit for a simulator with at least one hydraulic shaft shaped as a hydraulic cylinder, the piston device as piston surfaces of the discharge surface and a retracting surface acting in the opposite direction and also a supporting surface acting in the same direction with the discharge surface is disclosed. In addition, the exit and retraction surfaces are approximately the same size. A simulator, in particular a simulator device, with such a lifting unit is disclosed.

Description

P106596NL00

Title: Hydraulic lifting unit for a simulator and a simulator with such a lifting unit

The invention relates to a hydraulic lifting unit for a simulator, in particular a ground, water, air or space-bound vehicle, according to the preamble of claim 1 and a simulator according to claim 15.

A general hydraulic lifting unit comprises for movement and support of a load, such as a personal cabin of a simulator, a number of in particular, hydraulic axes. In this application, a hydraulic shaft is understood to mean a hydraulic cylinder. These shafts are compact, strong and powerful drives that are used in a large number of industrial automation applications. For example for driving simulators for said vehicles. In particular, such drives are designed to realize at least two movement processes, namely a fast simulation movement - hereinafter referred to as working movement - as well as a highly charged high-speed braking movement - hereinafter referred to as damping.

In the known hydraulic shaft of the applicant, in a prestressed hydraulic system, a hydraulic master cylinder and a reversible hydraulic machine are interconnected. The hydraulic cylinder can move in and out due to reversal of the hydraulic machine. The speeds occurring in the event of system overload or system failure can be brought to a halt by additional installed power within retardable values that are permissible for people, the forces occurring thereby being considerably higher than the hydraulic forces required for movement.

A disadvantage of this solution is that this hydraulic shaft, and therefore the hydraulic lifting unit, is relatively complex technically and that the installed power is considerably higher than is necessary for the actual movement of the load.

A hydraulic lifting unit to compensate for movements of a vehicle is shown in European patent EP 1993902 BI. The lifting unit herein has at least six hydraulic axes, which each have a piston device provided with three piston surfaces. Two of these are active in the opposite direction and can be activated with essentially non-compressible pressure medium. A third piston surface acts in the same direction as one of the first two and can be actuated with a compressible pressure medium, for example gas. The first two piston surfaces serve for acceleration in two opposite directions, the third serving to support a load of the lifting unit, a loading platform, and a damping of peak acceleration.

A disadvantage of this solution is that the pneumatic and hydraulic units provided for the pressure medium supply for the hydraulic shafts, for example hydraulic pumps and pressure medium accumulators, are relatively large and therefore require much space. This is accompanied by a large spatial distance from these aggregates to the hydraulic axes, resulting in long pressure medium pipes or pressure medium pipes. The elasticity at the pressure medium actuator directly influences a directness and accuracy of the operation of the hydraulic shafts as well as a control behavior negatively.

In contrast, the present invention aims to provide a hydraulic lifting unit that requires less space compared to the prior art. In addition, a simulator is provided that takes up less space.

The first object is achieved by a hydraulic lifting unit with the features of claim 1, the second with a simulator with the features of claim 15.

Advantageous embodiments of the hydraulic lifting unit are described in claims 2-14.

A hydraulic lifting unit for a simulator, in particular for a ground, water, air or space-bound vehicle, has at least one for movement and support of a load, in particular a passenger cabin in a force field, in particular under the influence of gravity. shaft which is formed via a hydraulic or hydro cylinder with a piston device with several piston surfaces. Each of the piston surfaces thereby defines a hydrostatic working space of the hydraulic cylinders, wherein for acceleration of the load in two opposite directions, a first and a second piston surface of the piston surfaces operating in the opposite direction can be actuated with pressure medium. The first piston surface is preferably effective against gravity. For support, in particular for weight compensation of the load, a third piston surface operating in the same direction with the first piston surface can be actuated with pressure medium. Accordingly, the first piston surface can be pressurized by the weight of the load when the third piston surface is relieved of pressure. According to the invention, the first piston surface and the second piston surface are approximately the same size.

As a result, with a movement of the piston device, the associated piston volumes of displacements of the working space bounded by the first two piston surfaces are approximately the same, so that a relatively large pressure expansion vessel, in particular a tank, can be omitted in relation to the prior art. . As a result, the lifting unit according to the invention requires less space in comparison with the prior art.

In a preferred embodiment, the lifting unit has a first hydro machine, through which the first piston surface (30) and the second piston surface (36) can be actuated with pressure means in a closed hydraulic circuit (42).

The first hydraulic machine is preferably reversible, so that the piston device can move in and out due to their different directions of rotation, pressure medium being passed between the first and the second piston surface, or vice versa.

In order to compensate for thermal expansion of the pressure medium and / or available slight surface differences between the first and second piston surfaces and / or to compensate for compressibility of the pressure medium, the lifting unit provides a preferred embodiment in a preferred embodiment with the first piston surface and with the second piston surface. fluid connectable first charged pressure medium accumulator. It can, for example, be gas-filled or spring-loaded or mass-loaded and preferably has a relatively relatively low pre-stress of, for example, between 0.5 and 10 bar. The pre-tensioning can of course also become higher.

The first charged pressure medium accumulator is preferably connectable, in particular connected, via a at least one anti-cavitation valve to a respective working connection of the first hydraulic machine in fluid communication.

The lifting unit is particularly space-saving and compact when the hydraulic machine is attached to the hydro cylinder in a preferred embodiment. As a result, the first hydro machine and the associated hydro cylinder form a structurally compact unit. Advantageously, pressure medium connections from the working connections from the first hydro machine to the hydro cylinder are much shorter, which reduces the elasticity of the hydraulic system first hydro machine hydro cylinder and makes operation of the hydro cylinder more direct and consequently more stable control behavior.

Particularly advantageous is an embodiment in which housing is a fixed working connection of the first hydro machine in contact, in particular mechanical, pressure-tight connection, with a working connection of the hydro cylinders fixed on the housing. Alternatively, the housing may be fixed working connections of the first hydraulic machine and the hydro cylinders in contact with an adapter plate with working channels arranged between these working connections.

In both cases, therefore, a pressure medium connection of the working connection through lines or hydraulic hoses has been omitted, thereby further improving the directness of the operation and the stability of the control behavior.

Preferably the first hydro machine has a constant cylinder capacity. It is preferably usable or reversible in different directions.

In a preferred embodiment, the hydraulic lifting unit has a variable operable speed, in particular electric drive machine, through which the first hydraulic machine can be driven, in particular is driven. The drive machine is preferably attached to the first hydro machine so that an even more compact drive unit of the hydro cylinder, first hydro machine and drive machine is provided.

The first hydro machine is in principle any at least two, in particular four quadrants operable hydro machines. This comprises, for example, a piston, in particular an axial piston or a gear machine or a combination of such hydro machines.

In a preferred embodiment, the hydraulic lifting unit has a second charged pressure medium accumulator through which the third piston surface is with actuatable pressure medium. The pressure applied to the third piston surface thus provides for the support of the load or, in other words, for a compensation of the weight of the load of the hydraulic lifting unit. This pressure can preferably be set to values corresponding to a compensation of the load of 0 to 100%, whereby a bottom-to-full compensation is possible. It is also possible to adjust the pressure to a value that leads to over-compensation of the load.

Alternatively or in addition to the second charged pressure medium accumulator, a preferred embodiment has a second hydro machine through which either the third piston surface can be actuated with pressure medium and / or the second charged pressure medium accumulator can be filled with pressure medium. The second hydraulic machine can preferably be formed, in particular a second, separate hydraulic circuit, through which the third piston surface can be actuated, in particular energized, with pressure medium.

In a particularly preferred embodiment, the lifting unit is designed such that via a feed device, from the third working space bounded by the third piston surface, the piston device is displaceable in a starting position, starting from the piston device, by the second hydro machine and / or by the second hydraulic accumulator a simulation mode can be accelerated / deflected in both directions. This allows the hydro cylinder, and therefore the lifting unit, to be designed more efficiently for a desired speed of movement and acceleration.

In the starting position, the load of the lifting unit is preferably completely or substantially completely or overcompensated. With full compensation, the pressure required for acceleration in the first workspace is very small compared to the pressure under or over compensated load. As a result, the first hydro machine can be made relatively weak or with little force, so that it can be made smaller and has a lower weight. This allows the hydraulic lifting unit to be built even smaller and lighter, which leads to greater flexibility of the hydro cylinder.

In a particularly preferred embodiment of the lifting unit, the hydraulic cylinder has, in particular a lower end position, an end position damping which, when a predetermined stroke falls below the pressure medium supply of the third working space is so limited, in particular limited, that the end position of the piston device is approached damped.

As a final position damping, a particularly preferred embodiment has a control valve apparatus, via which, between an intermediate position of the piston device and in a particularly lower end position of the piston device, a discharge of the pressure medium from a third working space bounded by the third piston surface is, in particular, limited.

The piston device is preferably formed over a mandrel or bolts of the hydraulic cylinder fixed on the housing and axially movable hollow piston.

The first piston surface is then formed via a front inner peripheral surface portion of the hollow piston, and the hollow piston has a radial collar extending on the outer periphery, on which an axial front of the second piston surface and on its other axial front the third piston surface is formed.

In the case of the hollow piston, the valve device is formed via a radial gap arranged between an outer circumferential surface portion of the radial collar and an inner circumferential surface portion of the hydro cylinder, with a mouth of a working connection facing towards the third working space in a range between the end position and the intermediate position of the piston device are arranged. The damping effect of the damping then occurs as soon as the radial collar starts to reach the mouth through a movement of the hollow piston.

An inventive simulator for a ground or water or air or space-bound vehicle provided with a hydraulic lifting unit which is formed according to at least one aspect of the foregoing description and a carrying device and / or a personal cabin that is hinged to support and acceleration in particular hydraulic shafts. The advantages described above also apply to the simulator.

Below, an embodiment of a simulator according to the invention with a lifting unit according to the invention is described in detail in two drawings. The drawings show:

FIG. 1 a side view of a flight simulator;

FIG. 2 a hydraulic shaft of the lifting unit according to FIG.

According to Fig. 1, a flight simulator designed as a simulator 1 has a hydraulic lifting unit 2 with six hydraulic cylinders configured as hydraulic shafts 8 which on the one hand is pivotable in all three spatial directions and is fixed to a bottom plate 10 and on the other hand hinged to a simulator platform 4 confirmed. A person cabin 6 of the simulator 1 is mounted on the simulator platform 4.

The hydro cylinders 8 are combined for hydraulic lifting unit 2 in the form of a hexapod. In deviation therefrom, the hydraulic lifting unit 2 can have fewer or more than six hydro cylinders. For example, embodiments with 1-5 hydro cylinders 8 are possible, provided that the restriction of the degrees of freedom is provided elsewhere, for example via fixed or loose bearings.

Each hydro cylinder is self-sufficient connected to two hydraulic circuits 42,44 for supplying pressure medium to its hydrostatic working space 34,38,41 (see Figure 2).

FIG. 2 shows one of the hydro cylinders 8 according to FIG. 1 in a schematic longitudinal section together with the peripheral hydraulic units for supplying pressure medium. The hydro cylinder 8 has a cylinder housing 12 in which a piston device 14 designed as a hollow piston is accommodated axially movable along a longitudinal axis 16. The hollow piston 14 passes through the cylinder housing 12 on a front surface 18 while the cylinder housing 12 has a cylinder bottom 20 on an opposite front surface. In the cylinder housing, approximately coaxially with the longitudinal axis 16, there is provided a cylindrical mandrel 22 fixed to the housing and surrounded on the outer circumference by the hollow piston 14. Thereby, the hollow piston 14 is mounted axially slidably on the mandrel and an inner peripheral surface 24 of the hollow piston 14 is in contact with an outer surface 26 of the mandrel.

At a nearby cylinder bottom end portion of the hollow piston 14, it has a radially enlarged collar or radial collar 28 which is in contact with its outer surface with an inner peripheral surface of the cylinder housing 12.

A first piston surface 30, a portion of the inner peripheral surface 24 and a front face 32 of the mandrel 22 define a first working space 34 of the hydro cylinder 8. An outer peripheral surface of the hollow piston 14, an inner peripheral surface part of the cylinder housing 12 and a second piston surface 36 define. a second working space 38 of the hydro cylinder 8. The cylinder bottom 20, an inner peripheral surface part of the cylinder housing 12 and a third piston surface 40 define a third working space 41 of the hydro cylinder.

With a supply of pressure medium to the first working space 34 the hollow piston 14 is driven out of the cylinder housing 12 and with a supply of pressure medium to the second working space 38 it moves in. Thus, the first piston surface 30 and the second piston surface 36 are opposed. The third piston surface 40 operates in the same direction with the first piston surface 30, so that the hollow piston 14 can also move out when the third working space is supplied with pressure medium. It should be noted that sliding in and out is only possible at the correct pressure and load. In the illustrated embodiment, however, the third working space serves to compensate for the weight of the platform 4 and the passenger cabin 6.

The hydro cylinder 8 configured in this way as a multiple surface cylinder is connected to a first closed hydraulic circuit 42 and to a second open hydraulic circuit 44. The first hydraulic circuit 42 has a first reversible hydro machine 46 which can be operated in all four quadrants and which is driven by a variable speed electric drive machine 48. The latter is flanged to the first hydro machine 46, which in turn is attached to the cylinder housing 12.

The first hydro machine 46 has a constant cylinder capacity.

A first working connection A of the first hydro machine 46 can be fluidly connected to the first working space 34 via a first pressure medium channel 50 which passes through the mandrel 22. In the pressure medium flow path of the first pressure medium channel 50, a control valve 52 is configured as a 2/2-way switch valve. It is configured as a valve seat and spring-biased in a closed position, in which the pressure medium connection of the first working space 34 is connected to the first working connection A. For the pressure medium inlet in the first working space 34 and for the pressure medium outlet in the second working space 38, or vice versa, it can be operated electromagnetically in a flow-through position. A second working connection B of the first hydro machine 46 is in fluid communication via a second pressure medium channel 54 with the second working space 38.

Moreover, the first hydraulic circuit 42 has a first gas-loaded pressure medium accumulator 56, which can be brought into pressure medium connection with the first and the second pressure medium channel 50, 54. It serves in the second hydraulic circuit 42 as a compensation for difference in volume due to thermal expansion and low compressibility of the pressure medium and due to possible small surface differences of the first and second piston surfaces 30, 36, for example formed by tolerances. For this purpose, an anti-cavitation valve 58 configured as a spring-loaded non-return valve 58 is provided in each pressure medium flow path of pressure medium channels 50 54. Fluidly parallel to each anti-cavitation valve 58, a pressure limiting valve 60 is provided through which the respective pressure medium channels 50, 54 are insured against exceeding an adjustable maximum pressure.

The first hydro machine 46 is flanged to the cylinder housing 12 in such a way that its working connections A B are directly connected to corresponding working connections of the hydro cylinders 8, more particularly to working connections of the working spaces 34, 38, which in the schematic representation of FIG. 2 is not immediately visible. In addition, the pressure medium connection of the first hydro machine 46 with the working spaces 34,38 has no lines or hydraulic rods, so that for each self-sufficient hydro cylinder 8 of the lifting unit 2 a direct reaction is achieved during pressure medium movement by the hydraulic machine 46.

In addition, the first hydraulic circuit 42 has an emergency valve 62 disposed in a pressure medium flow path from the first work space 34 to the second work space 38, and which is configured as a 2/2 shut-off valve with a spring biased position. As a result, the load can be lowered from any position of the hollow piston 14.

An additional pressure limiting valve 64 is provided in a pressure medium flow path from the first working space 34 to the first pressure medium accumulator 56, which pressure relief valve 64 is provided for pressure relief of the second pressure medium channel 50 when the control valve 52 is in its locking position.

The second hydraulic circuit 44 has, in this exemplary embodiment, a second hydro machine 66 which can only be operated in a quadrant and which is driven by a drive machine 68. A working connection A of the second hydro machine 66 is connected over a working line 70 to the third working space 41, wherein in the working line 70 a non-return valve 72 opening in the direction of the third working space 41 is arranged. The third operating line 70 passes through the cylinder housing 12 through a pressure medium channel and has aperture 74 facing the inner surface of the cylinder housing 12 in the third working space.

On the radial collar 28 a control valve device 90 with an end position damping is realized between the outer surface thereof and the inner surface of the cylinder housing 12 via a constant radial gap. The end position damping is then effective as soon as the radial collar 28 passes the mouth 74 with a movement of the hollow piston 14 in the direction of the cylinder bottom 20. From this point, the pressure medium outflow from the third working space 42 is limited via the radial gap of the control valve device 90 and thus a descent speed of the hollow piston (the load) is reduced.

From the work line 70 a work line 76 branches off which can be brought into fluid communication with a suction opening B of the second hydro machine 66. An emergency valve 78, configured as a 2/2-way flow valve with spring-biased flow position, is arranged in the work line 76 between the branch and the suction opening B, a screen downstream with a constant flow section. In simulation mode, the emergency valve 78 is actuated electromagnetically in its blocking position. In an emergency situation, for example in the event of a breakdown or by deliberately switching off the power supply, it switches to its flow-through position, relieving the second pressure medium accumulator 84 and the third working space 42, the hollow piston 14 being moved back and the load relatively fast to the start of the end position attenuation and sinks with a delay from the start of the end position attenuation. This is particularly necessary because otherwise a reduction of the burden in the case of overcompensation may not be possible.

In fluid communication with the suction port B, a third, configured as a feed tank, pressure medium accumulator 82 is provided. This can be done in open or closed design. A second, charged pressure medium accumulator 84 can be connected in fluid communication via the non-return valve 72 to the working connection A of the second hydro machine 66. This is gas loaded and configured such that via a gas connection of a gas space of the second pressure medium accumulator 84 for increasing the pressure it can be gas-capable (not shown). In addition, the pressure in the second pressure medium accumulator 84 can be adjusted via the second hydro machine. When the desired pressure is reached, the second hydro machine 66 can be switched off, whereby oil is prevented from returning from the third working space 42 to the second hydro machine via the non-return valve 72.

Arranged in a pressure medium flow path from the working connection A of the second hydro machine 66 through the mouth 74 is a pressure detection device 86 configured as a pressure sensor, with which the pressure in the third working space 42 can be monitored.

A hydraulic lifting unit for a simulator with at least one hydraulic shaft shaped as a hydro cylinder is disclosed, the piston device of which has piston surfaces of exit surface and a retraction surface acting in the opposite direction and also a support surface acting in the same direction with the exit surface. In addition, the exit and retraction surfaces are approximately the same size.

A simulator, in particular a simulator device, with such a lifting unit is disclosed.

Reference numeral list 1. Simulator 2. Hydraulic lifting unit 4. Platform 6. Personal cabin 8. Hydraulic shaft 10. Bottom plate 12. Cylinder housing 14. Piston device 16. Longitudinal axis 18. Front side 20. Cylinder bottom 22. Mandrel 24. Inner circumference surface 26. Outer circumference surface 28. Radial collar 30. First piston surface 32. Front side 34. First workspace 36. Second piston surface 38. Second workspace 40. Third piston surface 41. Third workspace 42. First hydraulic circuit 44. Second hydraulic circuit 46. First hydro machine 48. Drive machine 50. First pressure medium channel 52 Control valve 54. Second pressure medium channel 56. First pressure medium accumulator 58. Anti-cavitation valve 60, 64. Pressure limiting valve 62. Emergency valve 66. Second hydro machine 68. Drive machine 70. Work line 72. Check valve 74. Mouth 76. Work line 78. Emergency valve 80. Screen 82 Third pressure medium accumulator 84. Second pressure medium accumulator 86. Pressure detection device 90. Control valve device

Claims (15)

Hydraulic lifting unit for a simulator (1), in particular for a ground, water, air or space-bound vehicle, which has at least one axle formed by a hydro for movement and support of a load (4, 6) cylinder (8) with a piston device (14) provided with a plurality of piston surfaces (30,36,40), each of which delimits a hydrostatic working space (34, 38,42) of the hydro cylinders (8), whereby for the acceleration of the load (4,6), a first piston surface (30) of the piston surfaces (30,36,40) and a second piston surface (36) of the piston surfaces (30, 36, 40) operating in the opposite direction can be actuated with pressure medium, and wherein for supporting the load (4, 6) a third (40) piston surface of the piston surfaces (30, 36, 40) working with the first piston surface (30) in the same direction can be actuated with pressure medium, characterized in that the first piston surface (30) and the second piston surface (36) approximately r are the same size. Hydro lifting unit according to claim 1, with a first hydraulic machine (46) through which the first piston surface (30) and the second piston surface (36) can be actuated with pressure means in a closed hydraulic circuit (42). Lifting unit according to claim 1 or 2 with a fluid, first charged pressure medium accumulator (56) connectable to the first piston surface (30) and the second piston surface (36). Lifting unit according to claim 2 or 2 and 3, wherein the first hydraulic machine (46) is attached to the hydraulic cylinder (8). Lifting unit according to any of claims 2-4, wherein at least one housing fixed working connection (AB) of the first hydro machine (46) is in contact with a housing fixed working connection of the hydro cylinders (8), or wherein at least one housing fixed working connection of the first hydro machine and at least one housing fixed working connection of the hydro cylinder is in contact with an adapter plate with working channels arranged between these working connections. Lifting unit according to any of claims 2-5, wherein the first hydro machine (46) has a constant cylinder capacity. Lifting unit according to one of claims 2 to 6 with a variable speed drive machine (48) attached to the first hydraulic machine (46), via which the first hydro machine (46) can be driven. 8. Lifting unit according to one of the preceding claims with a second charged pressure medium accumulator (84) via which the third piston surface (40) can be actuated with pressure medium 9. Lifting unit according to one of the preceding claims or according to claim 8, with a second hydro machine (68) via which the third piston surface (40) can be actuated with pressure medium, and / or via which the second charged hydro accumulator (84) is filled with pressure medium . Lifting unit according to claim 8 or 9, which is designed such that via a feed device of the third working space (42) bounded by the third piston surface (40) by the second hydro machine (68) and / or by the second charged hydro accumulator (84) of the piston device (14) is displaceable in a starting position, from both the starting point of the piston device (14), in particular in a simulation mode, both sides can be swiveled out. Lifting unit according to one of the preceding claims, with a control valve device (90), via which at least one pressure medium outlet from a third (42) working space (34) bounded by the third piston surface (40) between an intermediate position and an end position of the piston device (14) , 38, 42). Lifting unit according to one of the preceding claims, wherein the piston device (14) is formed via a housing fixed mandrel (22) or bolts of the hydro cylinder (8) axially movable hollow piston (14). The lifting unit of claim 12, wherein the first piston surface (30) is formed via a front inner peripheral surface portion of the hollow piston (14), and wherein the hollow piston (14) has a radial collar (28) extending on the outer periphery, on which an axial front side of the second piston surface (36) is formed and on its other axial front side the third piston surface (40) is formed. A lifting unit according to claim 12 or 13, wherein the control valve apparatus (90) is formed via a radial gap arranged between an outer peripheral surface portion of the radial collar (28) and an inner peripheral surface portion of the hydro cylinder (8), and wherein a radial gap is provided in the third working space (42) pointing mouth (74), a working connection between the intermediate position (10) and the end position is formed. A simulator for a ground, water, air or space-bound vehicle, characterized by a hydraulic lifting unit (2), which is formed according to at least one of the preceding claims.