Mechanical switching unit, system and satellite

Abstract

To provide a mechanical switching unit, system and satellite.SOLUTION: A mechanical switching unit (10) for selectively moving a functional component (50) from a first position (14) to a second position (16) has a driving element (20), a driven element (30), a first holding point (15), and a second holding point (17). The driving element is set in motion by a drive (60). The driven element is in engagement with the driving element (20) and is set in motion by the driving element (20). The driving element (20) moves the driven element (30) from the first position (14) to the second position (16), and vice versa. In that case, the functional component (50) is moved from the first position (14) to the second position (16), and vice versa. The first holding point (15) exerts a first holding force on the functional component (50) in the first position (14). The second holding point (17) exerts a second holding force on the functional component (50) in the second position (16).SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a mechanical switching unit capable of selectively transferring and retaining a functional component in one of a plurality of positions, and further to a system including such a mechanical switching unit, and a satellite including such a system. [Background technology]

[0002] Currently, complex technological components are used on spacecraft such as satellites to, for example, generate, process, modify, transmit and / or receive signals, or switch specific signal paths in devices on the spacecraft.

[0003] For this purpose, it may be necessary to move functional components to a predefined position and to keep them there. As the complexity and performance of technical systems increase, the demands placed on the accuracy of the positioning of functional components also become higher. For example, optical components such as optical receivers or transmitters, or optical filters introduced into the optical path, need to be moved with high precision to a specific position in order to meet the demands placed on the transmission bandwidth and the channel quality of the optical transmission path. However, functional components may also be radio-frequency components, which need to be switched to one of several positions in the transmission path of a radio-frequency signal on a satellite, for example to select one of several possible signal paths.

[0004] To achieve high accuracy in positioning the functional components, for example, precision drives and / or gears can be used. However, such precision drives and / or gears can be subject to loads that arise during launch and / or transportation of a satellite into Earth orbit. High accelerations exert forces on the functional components and the drives and / or gears, which can cause play in the kinematic mechanisms, thereby adversely affecting the accuracy of positioning of the functional components. Summary of the Invention [Problem to be solved by the invention]

[0005] It can therefore be seen as a problem to provide a mechanical switching unit that switches a functional component to one of a number of positions and holds it in that position repeatedly and with high precision. [Means for solving the problem]

[0006] The above object is achieved by the subject matter of the independent claims. Further embodiments are evident from the dependent claims and the following description.

[0007] According to a first aspect, there is provided a mechanical switching unit for selectively moving a functional component from a first position to a second position. The mechanical switching unit comprises a drive element, a driven element, a first retention point and a second retention point. The drive element is designed to be actuated by a drive device. The driven element is designed to engage with and be actuated by the drive element. The drive element is engaged with the driven element such that the driven element can move from the first position to the second position and vice versa, thereby moving the functional component from the first position to the second position and vice versa. The first retention point is designed to apply a first retention force to the functional component in the first position, retaining the functional component in the first position. The second retention point is designed to apply a second retention force to the functional component in the second position, retaining the functional component in the second position.

[0008] The mechanical switching unit preferably also has a housing, in which the drive element, the driven element, the first retaining point and the second retaining point are arranged. The drive element is movably mounted on or in the housing. The driven element is also movably mounted on or in the housing. The first retaining point and the second retaining point are fixedly mounted on the housing.

[0009] The first and second retention points are spatially separated from one another such that the functional components at the first and second retention points are aligned in different positions or point in different orientations, and the first and second retention points act as holding or support surfaces on which the functional components rest and, in addition to resting thereon, are held in corresponding positions by active retention forces, as will be described below.

[0010] The mechanical switching unit described herein is particularly characterized in that the movement of the functional component from a first position to a second position or vice versa and the holding of the functional component in the first or second position are functionally separated from each other. The movement of the functional component is caused by the cooperation of a driving element and a driven element. In contrast, the holding in the respective position is functionally assigned to a first holding point or a second holding point.

[0011] This structure provides a kind of mechanical decoupling between holding in the first or second position and transitioning to the first or second position. Indeed, in space navigation applications, this structure reduces the load on the drive system, since the forces occurring during launch have little or no effect on the drive system, since it is not the drive and transmission that holds the functional component in place. Rather, these forces are absorbed by the first or second holding point.

[0012] The first and second retention points are separated from the driving and driven elements, such that when the functional component abuts against the first or second retention point, forces acting on the functional component are also received by the first or second retention point and have little or no effect on the driving and driven elements.

[0013] However, even if forces act on the driving element and the driven element, thereby increasing the engagement play, this does not affect the positioning accuracy of the functional component in the first and second positions, since the first and second positions are defined by the first and second retaining points.

[0014] This also reduces wear on the drive and / or the switching unit. The first and second holding points are rigidly and immovably connected to the mechanical switching unit, for example the first and second holding points are connected to a housing of the switching unit. This also ensures that the functional component to be positioned is repeatably held with very high precision in both the first and second positions, and that wear on the drive and / or the switching unit does not affect the precision of the positioning of the functional component.

[0015] In one embodiment, the driver element has a pin and the driven element has a slot, the pin engaging the slot to transfer motion of the driver element to the driven element.

[0016] For example, the pins of the drive element extend in a direction perpendicular to the plane of motion of the drive element.

[0017] The drive element can perform a translational or rotational movement. The drive element can be, for example, a drive gear and can be designed for a rotational movement.

[0018] If the driving element is a drive gear and performs a rotary movement, the pin extends parallel to the axis of rotation of the drive gear.

[0019] The driven element can also be designed as a gear, in which case the slot of the driven gear runs radially.

[0020] When the drive gear rotates about its central axis, the pin engages the slot so that it moves in a circular orbit about the central axis of the drive gear, moving the driven gear with it. During this rotational motion, the pin can move relative to the slot such that it moves radially along the slot, which also causes the driven gear to rotate about its central axis.

[0021] In another embodiment, the driving element is a driving gear designed to perform a rotary motion and the driven element is a driven gear designed to perform a rotary motion.

[0022] The drive and driven gears can mesh as in a Geneva gear mechanism. In this case, when the drive and driven gears are engaged with each other, the drive gear moves the driven gear together during part of the rotational motion. Basically, in a Geneva gear mechanism, besides a first state in which the drive and driven gears are engaged with each other and motion is transmitted from one to the other, there exists a second state in which the drive and driven gears are not engaged with each other. In the second state, the drive gear continues to rotate, but the driven gear stops rotating. From a certain point on, the pin engages another slot in the driven gear, causing the driven gears to move together again.

[0023] In this case, this mechanism of the Geneva gear mechanism is utilized to move a functional component by a drive gear actuating a driven gear, which is coupled to the functional component via a shaft, so that the functional component is also moved.

[0024] In particular, a Geneva gear mechanism is utilized here such that the drive element can perform movements in opposite directions, thereby causing the driven element to also move in the opposite direction, in order to move the functional component from a first position to a second position and vice versa.

[0025] It is therefore conceivable that in each state of the shifting unit the driving element and the driven element are engaged with each other. The basic structure of the Geneva gear mechanism is used here to allow play between the driving element and the driven element so that the forces acting on the functional component are not transmitted to the drive.

[0026] In another embodiment, the first retention point comprises a first magnetic element and / or the second retention point comprises a second magnetic element.

[0027] For example, permanent magnets or electromagnets may be arranged at the first and / or second holding points to apply a holding force to the holding elements of the functional component, thereby holding the functional component in the corresponding position.

[0028] Magnetic elements may also be arranged on the retaining element of the functional component, such that the magnetic elements of the first and second retaining points attract the retaining element and exert a retaining force thereon. Alternatively or additionally, the retaining element may be made of or comprise a ferromagnetic material.

[0029] To move the functional component from the first or second position, the drive must first overcome the holding force. As soon as the functional component approaches the other position, the magnetic element exerts an attractive force and pulls the functional component in the direction of the other position. Even if there is a small amount of play between the drive element and the driven element, the functional component is fixed at the first or second holding point by a holding force, which does not have to be applied by the engagement of the drive element with the driven element. If the holding is performed by the drive element and the driven element, wear due to this very engagement may cause play, which would mean that the functional component is no longer held with high precision in the same position.

[0030] In another embodiment, the first holding point has a first support surface designed so that the functional component rests on the first support surface in a first position, and / or the second holding point has a second support surface designed so that the functional component rests on the second support surface in a second position.

[0031] The functional component is held in the first and second positions with high precision after the corresponding support surfaces have become immobile relative to the housing of the mechanical switching unit. Even if there is play between the driving element and the driven element, the holding force exerted by the holding point repeatedly and with high precision draws the functional component to the same position. Thus, the precision of the positioning of the functional component in the first and second positions is independent of the precision of the drive formed by the driving element and the driven element.

[0032] In another embodiment, the first retention point has a first recess, the first recess being designed such that the functional component engages with the first recess in a first position, and / or the second retention point has a second recess, the second recess being designed such that the functional component engages with the second recess in a second position.

[0033] The first recess and the second recess are arranged, for example, at or near the first or second holding point in a housing of the mechanical switching unit. When the functional component is in the first position, the holding element of the functional component locks in the first recess. When the functional component is in the second position, the holding element of the functional component locks in the second recess. This can contribute to a higher force being required to move the functional component from the first or second position.

[0034] In addition to or instead of using a magnetic element, two recesses can be provided at the first and second retention points.

[0035] It is conceivable that the mechanical switching unit does not have a fixed support surface, but instead only has recesses. For example, several recesses can be arranged at predefined points along the line of motion of the functional component. This makes it possible for the functional component to be able to switch from one recess to the next without changing direction. In this case, the functional component can, for example, perform a rotational movement.

[0036] In another embodiment, the drive element is coupled to the driven element such that the driven element can move in two opposing directions.

[0037] Thus, the driven element can move the functional component from a first position to a second position and back from the second position to the first position, for example by a drive device coupled to the drive element being moved in different directions.

[0038] According to another aspect, there is provided a system comprising a mechanical switching unit as described herein, a drive device, and a functional component, the drive device being coupled to a drive element such that motion of the drive device is transferred to the drive element, and the functional component being coupled to a driven element such that motion of the driven element is transferred to the functional component.

[0039] The drive is, for example, an electromechanical drive, such as an electric motor. Alternatively, it is also conceivable that the drive is a hydraulic or pneumatic system. The drive essentially provides the motion that is transmitted to the drive element. The drive can perform a rotational or translational motion and can, for example, be coupled to a rotating shaft of the drive element.

[0040] The functional component may also be arranged on the rotating shaft of the driven element. When the driven element rotates about the axis of rotation, the functional component is moved along with it during this rotational movement. The functional component is arranged with a retaining element which cooperates with the first and second retaining points (and associated support surfaces and recesses) as described above.

[0041] In one embodiment, the functional component is an optical element or a radio frequency component.

[0042] An optical element can be, for example, an optical filter, an emitter, or an optical receiver, which must be moved to a specific position and / or orientation and kept exactly in this position and / or orientation. Generally speaking, an optical element can be any optical component that can affect the geometrical and / or spectral properties of a light beam. In case of a high-frequency component, it can be moved to different positions, for example to switch to different signal paths.

[0043] In another aspect, there is provided a satellite comprising a system as described herein.

[0044] The mechanical switching unit structures described herein can be advantageously used in space navigation, where high and repeatable accuracy in positioning is required for certain functional components (e.g., optical elements, radio frequency components, etc.), and where large forces may be present during launch and / or transportation of the spacecraft that may lead to wear on the mechanical components of the switching unit.

[0045] The changeover unit described here uses elements of different structures for two tasks: moving and holding the functional component. For moving, a drive is used, in which a driving element and a driven element cooperate. For holding, a static holding point is used. Thus, play in the kinematic mechanism of the changeover unit does not affect the positioning accuracy in the first and second positions. Thus, the forces occurring during launch and / or transportation of the satellite into Earth orbit can at most affect the play in the kinematic mechanism (drive, driving element, driven element), which has no or at most only a slight effect on the positioning accuracy at the first and / or second holding points. The first and second holding points are preferably arranged in the housing of the mechanical changeover unit and have a strength such that the forces occurring during launch and / or transportation do not cause plastic deformation of the holding points.

[0046] Some details will now be explained in more detail with reference to the attached drawings, which are schematic and not to scale, and in which the same reference signs refer to the same or similar elements. [Brief description of the drawings]

[0047] [Figure 1] FIG. 2 is a schematic diagram of a mechanical switching unit. [Diagram 2] FIG. 1 is a schematic diagram of a system with a drive device, a mechanical switching unit and functional components. [Diagram 3] FIG. 1 is a schematic diagram of an artificial satellite. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0048] 1 shows a mechanical switching unit 10. The mechanical switching unit 10 comprises a housing 12. The remaining components are arranged in the housing 12. The mechanical switching unit 10 comprises a driving element 20, which may also be referred to as an input. The mechanical switching unit 10 further comprises a driven element 30, which may also be referred to as an output.

[0049] The driving element 20 is designed as a drive gear and is connected to the housing 12 via a rotating shaft 22. The driving element 20 is designed for rotational movement around the rotating shaft 22, which is at the same time the central axis of the driving element 20. The driving element 20 has a pin 24. The driving element 20 is at least partially in contact with a contour 36 of the driven element 30.

[0050] The driven element 30 is also designed as a driven gear and is connected to the housing 12 via a drive shaft 32. The drive shaft 32 forms the central axis of the rotational movement of the driven element 30 and connects it to the functional component. The driven element 30 has a radial slot 34.

[0051] The pin 24 engages in the slot 34, whereby the driving element 20 and the driven element 30 engage with each other. In the illustration, when the driving element 20 rotates clockwise, the pin 24 moves the driven element 30 together. In this case, the pin 24 also performs a relative movement in the slot 34, approaching the central axis 32. The driven element 30 performs a rotational movement in the counterclockwise direction, which moves the functional components together during this rotational movement.

[0052] A first retention point 15 and a second retention point 17 are arranged on the housing 12. As shown, the functional component can assume a first position 14 when it abuts against the first retention point 15. The functional component assumes a second position 16 when it abuts against the second retention point 17. In the illustration of Figure 1, a retention element 55, which is part of the functional component (see Figure 2), is shown as representative of the functional component.

[0053] 1 , the retaining element 55 abuts against the first retaining point 15 and is in the first position 14. If the driven element 30 rotates counterclockwise, the functional component also rotates counterclockwise and the retaining element 55 moves along the direction of movement 52 from the first position 14 to the second position 16. In the second position 16, the retaining element 55 abuts against the second retaining point 17.

[0054] The driving element 20 and the driven element 30 can be moved in opposite directions, i.e. in the example of Fig. 1 this is clockwise or counterclockwise, so that the retaining element 55 of the functional component can be moved in both directions along the direction of movement 52 in order to selectively move the functional component either to the first position 14 or to the second position 16.

[0055] With this structure, the kinematic mechanism including the driving element 20 and the driven element 30 transfers the holding element 55 and the functional component from the first position 14 to the second position 16 or vice versa, and in the first and second positions the respective holding points 15, 17 exert a holding force on the holding element 55 to hold the functional component in this position. Thus, despite the play in the kinematic mechanism between the driving element 20 and the driven element 30, the functional component can be held in the corresponding position repeatably and with high precision.

[0056] FIG. 2 shows a system 1 comprising a mechanical switching unit 10 as shown in FIG. 1, a drive 60 and a functional component 50.

[0057] The drive 60 is, for example, an electric motor coupled to the rotating shaft 22 (see FIG. 1 ) of the drive element 20. When the drive 60 rotates the drive element 20, a corresponding motion is transmitted to the driven element 30. The drive shaft 32 in turn rotates the functional component 50.

[0058] The functional component 50 can be moved such that the retaining element 55 moves between the first retaining point 15 and the second retaining point 17. In the first position, the retaining element 55 abuts the first retaining point 15. In particular, the retaining element 55 abuts the first support surface 18. The first support surface 18 is part of the first retaining point 15. The illustration in Fig. 2 shows the functional component 50 and the retaining element 55 in the first position. In the second position, the retaining element 55 abuts the second retaining point 17, in particular the second support surface 19.

[0059] A recess 18a is arranged near the first holding point 15. When the functional component 50 is in the first position, the holding element 55 is located in the recess 18a and is further held in the first position by the first holding point 15, e.g., a magnetic element. Similarly, a recess 19a is located near the second holding point 17. In the second position, the holding element 55 is located in the recess 19a and is further held in the second position by the second holding point 17, e.g., a magnetic element.

[0060] The system 1 of FIG. 2 can be described in an exemplary application as follows. This system refers to the realization of a kinematic mechanism that allows the rotation and precise positioning of functional components such as optical components and HF elements. This system uses the principle of the Geneva gear mechanism 20, 30, which, in combination with a magnetic stopper or locking system formed by the holding points 15, 17 and the recesses 18a, 19a, allows the mechanical decoupling of the drive 60 from the moving part (functional component 50) in the end positions 14, 16. The functions of movement and positioning are then separated. The combination of these two special approaches allows for a precise and repeatable holding of the position of the functional component 50, regardless of the accuracy of the gearing 20, 30 and the associated drive 60.

[0061] The drive shaft 22 and the rotor shaft 32 (Rotorwelle) are arranged in parallel and are connected to each other via a Geneva gear mechanism 20, 30. The two functions of movement and holding are separated from each other. The rotational movement is realized by a drive 60 including a drive gear 20 and a driven gear 30. The precise holding is solved by a magnetic stopper or locking system, i.e. holding points 15, 16 and the associated holding elements 55.

[0062] To separate the functions, a Geneva gear mechanism 20, 30 is used. The Geneva gear mechanism 20, 30 ensures that the rotary motion of the drive shaft 22 is transmitted to the rotor shaft 32 as a stepwise motion. The Geneva gear mechanism (Malteserkreuz) 30 is a disk-shaped component with one or more slots 34, in the example of FIG. 2 only one slot 34 is provided. This disk is attached to the rotor shaft 32. The drive shaft 22 drives an eccentrically supported pin 24. When the drive shaft 22 rotates, the pin 23 moves along the slot 34 and rotates the Geneva gear mechanism 30 one more step. In contrast to the typical design of the Geneva gear mechanism, in this application the play between the pin 24 and the slot 34 is deliberately chosen large, since the final positioning of the functional component 50 is performed by a magnetic stopper or locking system.

[0063] After the functional component 50 has been moved to the desired position by the Geneva gear mechanism 20, 30, the drive can be rotated further to a rest position in which the pin 24 is no longer engaged with the slot 34. Switching to the second position is achieved by reversing the direction of rotation. A magnetic stopper or locking system holds the functional component 50 in the correct position. In case of high external loads (e.g. vibrations), the functional component 50 can be temporarily moved out of its position only within the play area by the locking contours 36 of the Geneva gear mechanism. The correct position of the functional component 50 is then readjusted by the magnetic stopper or locking system.

[0064] If a magnetic locking system is used instead of the magnetic stopper, it is possible to switch without turning, but the positioning accuracy will decrease.

[0065] In the example of Fig. 2, the gearing allows the functional component 50 to rotate through 90°. Precise positioning is provided by magnetic stops 15, 17. Separating the movement and holding functions allows the use of drives 60 and gearings 20, 30 with lower precision requirements.

[0066] This concept can be applied to other angles and a greater number of positions.

[0067] Very high demands on accuracy can be achieved by magnetic stopper or locking systems 15, 16. A cheaper drive 60 with lower accuracy requirements can be used. The transmission play between the drive element 20 and the driven element 30 does not affect the positioning or orientation of the functional component 50 in the first or second position. Furthermore, due to the play in the coupling, the mechanical switching unit is robust to assembly tolerances. In de-energized operation, the drive 60 can be disengaged without affecting the holding forces at the first and second holding points 15, 17. After switching the functional component 50 from the first position to the second position (or vice versa), the drive train is disengaged from the functional component 50 and does not act on the functional component 50 when loaded during launch. The locking contours 36 of the Geneva gear mechanism prevent twisting when high mechanical loads are applied.

[0068] FIG. 3 shows diagrammatically a satellite 100 with a system 1 arranged as described in FIG. 2 for positioning a functional component 50 on the satellite and maintaining it in a desired position.

[0069] Additionally, it is noted that "comprises" or "having" does not exclude other elements or steps, and that the singular does not exclude a plurality. Furthermore, it is noted that features or steps described with reference to one of the above exemplary embodiments can also be used in combination with other features or steps of other of the above exemplary embodiments. Reference signs in the claims should not be considered as limiting. [Explanation of symbols]

[0070] 1 System 10 Mechanical switching unit 12. Housing 14 1st position 15 First Holding Point 16 Second position 17 Second Holding Point 18 First Support Surface 18a First recess 19 Second Support Surface 19a Second recess 20 Driving element, input 22 Rotating shaft, central axis 24-pin 30 Follower element, output 32 Drive shaft, central axis 34 Slot, engagement 36 Contour 50 Functional Components 52 Direction of motion 55 Retention element 60 Drive unit 100 satellites

Claims

1. A mechanical switching unit (10) for selectively moving a functional component (50) from a first position (14) to a second position (16), said mechanical switching unit (10) comprising: a drive element (20) designed to be actuated by a drive device (60); a driven element (30) designed to engage with and be actuated by said driving element (20); A first holding point (15); A second retention point (17), said driving element (20) is engaged with said driven element (30) such that said driven element (30) can move from said first position (14) to said second position (16) and vice versa, thereby moving said functional component (50) from said first position (14) to said second position (16) and vice versa; the first retention point (15) is designed to apply a first retention force to the functional component (50) at the first position (14) to retain the functional component (50) in the first position (14); the second retention point (17) is designed to apply a second retention force to the functional component (50) at the second position (16) to retain the functional component (50) in the second position (16). Mechanical switching unit.

2. The driving element (20) has a pin (24), The driven element (30) has a slot (34), The pin (24) engages the slot (34) to transmit motion of the driving element (20) to the driven element (30). A mechanical changeover unit (10) according to claim 1.

3. said driving element (20) being a driving gear designed to perform a rotational movement; said driven element (30) being a driven gear designed to perform a rotational movement; A mechanical changeover unit (10) according to claim 1 or 2.

4. The first retention point (15) has a first magnetic element, and / or the second retention point (17) having a second magnetic element; A mechanical changeover unit (10) according to any one of the preceding claims.

5. said first holding point (15) having a first support surface (18) designed such that said functional component (50) rests on said first support surface (18) in said first position (14); and / or the second holding point (17) has a second support surface (19) which is designed such that the functional component (50) rests on the second support surface (19) in the second position (16), A mechanical changeover unit (10) according to any one of the preceding claims.

6. said first holding point (15) having a first recess (18a), said first recess (18a) being designed such that said functional component (50) engages said first recess (18a) in said first position (14); and / or the second holding point (17) has a second recess (19a), the second recess (19a) being designed such that the functional component (50) locks into the second recess (19a) in the second position (16); A mechanical changeover unit (10) according to any one of the preceding claims.

7. The driving element (20) is coupled to the driven element (30) such that the driven element (30) can move in two opposite directions (52). A mechanical changeover unit (10) according to any one of the preceding claims.

8. A system (1), A mechanical switching unit (10) according to any one of claims 1 to 7, A drive unit (60); A functional component (50), The drive device (60) is coupled to the drive element (20) such that the motion of the drive device (60) is transmitted to the drive element (20); The system, wherein the functional component (50) is coupled to the driven element (30) such that motion of the driven element (30) is transmitted to the functional component (50).

9. The functional component (50) is an optical element or a high-frequency component. A system (1) according to claim 8.

10. A satellite (100) comprising a system (1) according to claim 8 or 9.

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