Transmission

Abstract

The invention relates to a transmission for orthopaedic devices, comprising: a planetary gear set (10), which has a central sun gear (11); a plurality of planet gears (12), which are rotatingly mounted on a planet carrier (13) and are force-transmittingly coupled to the sun gear (11); and a ring gear (14), which has an inner circumference in which the planet gears (12) circulate; the sun gear (11) is coupled to a drive shaft (2) and the planet carrier (13) is coupled to an output element (20); the output element (20) being coupled to two contradirectionally oriented, shiftable freewheels (30, 40); it being possible, in a first rotational direction of the drive shaft (2), for a first freewheel (30) to be brought directly into force-transmitting engagement with the drive shaft (2) and, in a second rotational direction of the drive shaft (2) counter to the first rotational direction, it being possible for a second freewheel (40) to be brought into force-transmitting engagement with the planet carrier (13) in order to drive the output element (20).

Description

[0001] manual transmission

[0002] The invention relates to a manual transmission for orthopaedic devices with a planetary gear having a central sun gear, with a plurality of planetary gears mounted to rotate on a planetary carrier, which are coupled to the sun gear in a power-transmitting manner, and with a ring gear having an inner circumference in which the planetary gears rotate, the sun gear is coupled to a drive shaft, the planetary carrier is coupled to an output element.

[0003] Orthopedic devices, particularly orthoses, exoskeletons, and prostheses, often have components that are pivotally or slidably mounted to one another. Various measures are taken to influence the relative movement between the components, for example, the upper and lower parts of an orthosis spanning a joint or a prosthesis with a joint. Mechanical stops can be provided to limit the maximum pivot angle or displacement distance. To influence the pivoting or displacement movement, energy storage devices or dampers can be arranged between the two components as passive influencing devices.

[0004] Active orthopedic devices have a drive that initiates or supports a relative movement between the components, or counteracts the relative movement with resistance. Electric motors are often provided for this purpose and are activated, deactivated, or modulated via a control device. The electric motor is coupled to an accumulator or battery to enable the corresponding active influence or initiation of a relative movement. The space available in orthopedic devices is limited for both the energy storage device and the drive in the form of motors. Motors that can generate high torques are often too heavy, especially in orthopedic devices for the upper extremities. Therefore, small, fast-rotating motors are generally used, which are coupled to the component to be driven or influenced via a gear system.

[0005] A clutch for prostheses, in particular for prosthetic gripping prostheses, is known from US Pat. No. 8,157,446 B1. The clutch has a chassis on which at least one finger prosthesis is articulated. The clutch also has a drive element, an output element, and a switching device that switches between two gear stages depending on the torque applied to the output element. The switching device operates independently of the direction of rotation of the output element and switches back and forth between the gear stages with different ratios. This is achieved via clamping bodies that are in contact with the switching device and couple the output element to the drive element in a torque-controlled manner.

[0006] The requirements for a drive train of an active orthopedic device are diverse and depend in particular on the design of the orthopedic device and the type and manner of use. For orthopedic devices of the lower extremities, a basic distinction can be made between application in the swing phase and application in the stance phase. In the swing phase, lower moments and a high adjustment speed are generally required, whereas in the stance phase, high moments at comparatively low adjustment speeds are necessary. In an active knee joint, for example, only low adjustment moments below 10 Nm are required during the initiation of the swing phase, whereas in a stance phase extension, high moments greater than 30 Nm are required at low knee angular velocities below 1007s in the extension direction.When designing and optimizing the drive train, it is therefore necessary to meet a wide range of requirements. With conventional manual transmissions, it is difficult to optimize the drive train so that the various operating points are optimally achieved. The object of the present invention is to provide a manual transmission that enables the drive of an orthopedic device to operate at an optimal operating point in order to meet different requirements regarding adjustment speed and adjustment torque.

[0007] This object is achieved by a manual transmission having the features of the main claim. Advantageous embodiments and further developments of the invention are explained in more detail in the subclaims, the description, and the figures.

[0008] The manual transmission for an orthopedic device with a planetary gear having a central sun gear, with a plurality of planet gears which are rotatably mounted on a planet carrier and are coupled to the sun gear in a power-transmitting manner, and with a ring gear which has an inner circumference in which the planet gears rotate, wherein the sun gear is coupled to a drive shaft and the planet carrier is coupled to an output element, is characterized in that the output element is coupled to two counter-oriented, switchable freewheels, wherein in a first direction of rotation a first freewheel can be brought into direct power-transmitting engagement with the drive shaft and in a second direction of rotation opposite to the first direction of rotation a second freewheel can be brought into power-transmitting engagement with the planet carrier in order to drive the output element.With such a manual transmission, it is possible to operate the drive at a good operating point and thus with good efficiency in different load situations depending on the direction of rotation. This means that energy consumption can be reduced and the drive can be dimensioned smaller overall. This saves both space and weight, improving the overall system of the orthopedic device. With the manual transmission, it is possible to achieve high speeds in one adjustment direction, while in the opposite adjustment direction a high torque can be provided at lower adjustment speeds. Thanks to the switchable freewheels, the output element is either directly engaged with the drive shaft to transmit power, or in the other direction of rotation via the planetary gear, whereby different gear ratios are set depending on the direction of rotation.In the first direction of rotation, there is a direct coupling between the drive shaft and the output element, so that, for example, the speed of the engine is transmitted directly to the output element, while in the second direction of rotation a gear ratio of, for example, 1 to 6 results.

[0009] In one embodiment, the freewheels have clamping bodies which, in an engaged position, engage with the output element and the drive shaft or the planet carrier in a force-transmitting manner, wherein the clamping bodies are assigned switching pins which move the clamping bodies from the engaged position into a release position in which the clamping bodies are disengaged, and back again. Both freewheels have clamping bodies which are arranged between the output element and the drive shaft or a component driven by the drive shaft. The clamping bodies slide or roll along the surface of the drive shaft or a component driven by the drive shaft, in particular the planet carrier, and clamp themselves with the output element depending on the direction of rotation. The driven component takes the clamping body with it in the respective direction of rotation. In the engaged position, the drive shaft orthe planet carrier is clamped to the output element so that the output element can be driven by the drive shaft. In the opposite direction of rotation, due to the given geometric relationships between the sprags, the output element and the drive shaft or the planet carrier, no power can be transferred from the drive shaft to the output element for the respective freewheel, or only so little that no rotation of the output element occurs. In order to bring the sprags into a position in which they are disengaged from the output element and the drive shaft or from the component driven by the drive shaft, the sprags are assigned switching pins via which the sprags can be moved from the engaged position to a released position.For example, the sprags are moved away from the surface of the drive shaft or the driven component, especially the planetary carrier, or a clearance is created between the sprags and the drive shaft or planetary carrier, so that no power is transmitted. The actuatable shift pins make it possible, in particular, to engage or disengage the sprags in a controlled manner, which also increases the precision of the manual transmission. If the sprags have already been brought into engagement with the output element and, for example, the drive shaft by the shift pins, the freewheels are activated in the corresponding direction of rotation with less play or free travel.Conversely, if the clamping bodies have already been adjusted from the engaged position to the release position, reversing the direction of rotation is made easier because the clamping bodies no longer have to be moved into the release position by the drive.

[0010] In one embodiment, the switching pins, in particular all switching pins, are arranged on a rotatably mounted driver. By rotating the driver about a rotational axis, it is possible to simultaneously activate or deactivate all clamping bodies, or to engage or disengage them with the output element and the drive shaft or the planet carrier.

[0011] In one embodiment, the freewheels are arranged coaxially with one another and axially one behind the other, allowing for a compact design. The diameters of the freewheels can vary; in principle, it is also possible to use the same diameters, allowing identically constructed freewheels to be used axially offset one behind the other. A clamping body for the first freewheel and a clamping body for the second freewheel are arranged on at least one switching pin, with the two clamping bodies for the first freewheel and the second freewheel being designed separately.The switching pin or all switching pins, in particular the switching pins on the rotatably mounted driver, project axially into both the first freewheel and the second freewheel and enable the clamping bodies to be moved from an engaged position to a release position and back again by a rotary movement in one direction or the other. Preferably, an actuator is assigned to the driver to effect the adjustment; in particular, the driver is coupled to the actuator. The actuator can be designed as an active drive, in particular as an electric motor or another electrically or electronically activatable, deactivatable, and / or modulatable drive, which can also be designed, for example, as a lockable or activatable energy accumulator, for example a spring.The clamping elements and the driver are designed in such a way that all clamping elements are held in the release position. The driver with the switching pins is thus able to assume a position in which the clamping elements are not engaged in either the first freewheel or the second freewheel. In this position, all clamping elements are in the release position, allowing complete decoupling of the drive shaft from the output element.

[0012] In one embodiment, the first freewheel is formed in a sleeve-like section of the output element. The clamping bodies of the first freewheel are arranged on the outside of an output section arranged or formed on the drive shaft and slide or roll on it. A sleeve-shaped part of the output element is then arranged outside the clamping bodies, in which the clamping bodies are clamped in one direction of rotation of the drive shaft and can roll or slide off in the other direction without transmitting force to the output element. The output section can be formed integrally on the drive shaft; alternatively, the output section is designed as a separate assembly that is driven by the drive shaft and replaced in the corresponding direction of rotation.

[0013] In one embodiment, the output element is rotatably mounted on an inner circumference of the planet carrier; in particular, the output element is sleeve-shaped and projects into the inner circumference of the planet carrier. The clamping bodies of the second freewheel are arranged between the inner side of the output element and an outer side of a sleeve section of the planet carrier. The output element is mounted, for example, in roller bearings or ball bearings within the planet carrier, wherein the bearings are arranged on the outer side of the output element and on the inner side of the planet carrier in an inner circumference, for example in an annular space. The planet carrier is then brought into contact with the drive shaft and the output element in an engaged position via the clamping bodies on the inner side of the output element, clamping and transmitting force.

[0014] The planetary gear can be designed as a friction gear or a gear drive. In a gear drive configuration, external gearing is provided for the sun gear and the planet carrier, while internal gearing is formed on or in the ring gear.

[0015] In one embodiment, receiving pockets are arranged or formed in the output element, which increase radially in a circumferential direction. The clamping elements are located in the receiving pockets, wherein the enlargement of the receiving pockets in the radial direction is dimensioned such that, at least in the end positions viewed in the circumferential direction, a release position without relevant power transmission or an engagement position in which the output element is or can be coupled to the drive shaft in a clamping manner, optionally directly or via the planet carrier. The enlargement of the receiving pockets for the clamping elements of the first freewheel runs opposite to the enlargement of the second freewheel; the freewheels are thus oriented in opposite directions and produce a direction-dependent, different gear ratio.In order to be able to completely decouple the drive shaft from the output element, the receiving pockets for the clamping elements are dimensioned and positioned in such a way that, in particular via the driver, the clamping elements can be brought out of engagement with both the first freewheel and the second freewheel, so that forces cannot be transmitted in either direction.

[0016] In order to be able to effect a radial displacement of the clamping bodies relative to the output element or the drive shaft, a component connected to it, or the planet carrier, the clamping bodies have elongated holes which serve to accommodate the switching pins. In one embodiment, each clamping body has a single elongated hole so that, in particular when the driver is rotated towards an engaged position, the clamping bodies rest on their outer circumference against the receiving pockets and, when rotated in the circumferential direction relative to the corresponding freewheel, the clamping bodies move radially inwards towards the planet carrier or the drive shaft until there is sufficient contact between the clamping bodies and the corresponding surface of the drive shaft or the planet carrier to further drive the clamping bodies and clamp them.

[0017] An exemplary embodiment of the invention is explained in more detail below with reference to the figures. Like reference numerals in different figures denote like components. Not all reference numerals are shown in all drawings to ensure clarity. They show:

[0018] Figure 1 - a sectional view through a manual transmission;

[0019] Figure 2 - a perspective view of the gearbox with some components removed;

[0020] Figure 3 - Figure 2 with a driver;

[0021] Figure 4 - a view from a different perspective without a ring gear;

[0022] Figure 5 - a front view of an embodiment; and

[0023] Figure 6 - a variant of Figure 5.

[0024] Figure 1 shows a sectional view of a manual transmission for orthopedic devices with a planetary gear 10. The planetary gear 10 has a central sun gear 11 with external teeth 110 and, in the illustrated embodiment, is designed as part of a drive shaft 2. The drive shaft 2 is driven by a motor, either directly or via an intermediate gear. As an alternative to the one-piece design of drive shaft 2 and sun gear 11, the sun gear 11 can also be attached to the drive shaft 2 to transmit torque. The sun gear 11 with the external teeth 110 engages with external teeth 120 of several planetary gears 12, which are coupled to the sun gear 11 to transmit force. The planetary gears 12 are arranged within a ring gear 14, on the inner circumference of which an internal toothing 140 is formed in order to mesh with the external toothing 120 of the planetary gears 12.The planet gears 12 are rotatably arranged on a planet carrier 13, which is mounted on the drive shaft 2 coaxially to the axis of rotation of the drive shaft 2 via a bearing, e.g. a needle bearing or a plain bearing. In the illustration in Figure 1, the drive shaft 2 is driven at the left end, with the drive shaft 2 being mounted in a housing in a ball bearing 60. The ring gear 14 is also fastened in the housing. The drive shaft 2 projects into the ring gear 14, and in the axial direction in front of the ring gear 14 there is the planet carrier 13, which the drive shaft 2 also passes through. In the axial direction in front of the planet carrier 13 there is an output section 15, which in the illustrated embodiment has a larger outer diameter than the external toothing 110 of the sun gear 11.

[0025] As an alternative to designing the planetary gear 10 as a gear transmission, it is also possible to design it as a friction gear transmission. Instead of the external teeth 110, 120 on the sun gear 11 and the planet gears 12, as well as the internal teeth 140 in the ring gear 14, the planet gears 12 then run on untoothed surfaces.

[0026] The planet gears 12 are rotatably mounted on pins on the planet carrier 13. On the side of the planet carrier 13 opposite the planet gears 12 and the ring gear 14, an annular space is formed in which a sleeve-shaped output element 20 is mounted. The output element 20 has an external bearing, which in the illustrated embodiment is designed as a needle bearing or roller bearing and is arranged between the outer inner circumference of the annular space. The output element 20 has form-locking elements on its outer side for engaging with the component to be driven. Gears, gear segments, or a toothing can also be arranged or formed on the outer side.Two freewheels 30, 40 are arranged within the sleeve-shaped output element 20, the first freewheel 30 being arranged between the output section 15 of the drive shaft 2 and the output element 20, while the second freewheel 40 is arranged between the outer side 1333 of a sleeve section 133 of the annular space of the planet carrier 13. The operation of the freewheels 30, 40 will be explained later. The freewheels 30, 40 have clamping bodies 32, 42 which are attached to the inner side 24 of the.

[0027] Output element 20 and once on the outside of the output section 15 and once of the sleeve section 133 or can be brought into engagement therewith. The clamping bodies 32, 42 are arranged essentially concentrically around the axis of rotation of the drive shaft 2 and are arranged axially one behind the other, wherein the clamping bodies 32 of the first freewheel 30 are arranged in a plane in front of the plane of the clamping bodies 42 of the second freewheel 40. The clamping bodies 32, 42 are penetrated by switching pins 52, which are fastened to a driver 50, which is mounted on the drive shaft 2 via a bearing 60. In the illustrated embodiment, the switching pins 52 are designed as separate elements that are fastened in the driver 50; alternatively, a one-piece design of switching pins 52 and driver 50 is provided.In the illustrated embodiment, the driver 50 is coupled to an actuator 80, which can be a force accumulator or a motor drive, via which the position of the driver 50 relative to the output element 20 and the clamping bodies 32, 42 can be adjusted. The actuator 80 can also be a return spring, which ensures that a clamping body 32, 42 is always engaged in a force-transmitting manner or serves to move or hold the clamping bodies 32, 42 in an engaged position and / or a released position.

[0028] The freewheels 30, 40 are activated in opposite directions of rotation of the drive shaft 2, so that upon rotation in a first direction of rotation, the first freewheel 30 is engaged to transmit power, and the output element 20 is brought into clamping and power-transmitting engagement with the drive shaft 2. This makes it possible to transmit the speed of the drive shaft 2 directly to the output element 20. In the opposite direction of rotation, the second freewheel 40 can be activated such that, after the transmission via the planetary gears 12, the planet carrier 13 is coupled to the output element 20 in a power-transmitting manner, so that rotation of the output element 20 with a greater torque and a lower speed is achieved due to the transmission by the planetary gear.

[0029] Figure 2 shows a perspective view of the gearbox of Figure 1 without the driver 50. The drive shaft 2 has a square shaft end to allow coupling to a drive. On the outside of the drive shaft 2, the bearings 60 for mounting in the housing and the mounting of the driver 50 can be seen. In the axial direction behind the bearings 60, the output section 15 of the drive shaft 2 can be seen, along the outside of which clamping bodies 32 of the first freewheel 30 slide. Switching pins 52 extend through the clamping bodies 32, which in turn are fastened in the driver (not shown). All of the clamping bodies 32 of the first freewheel 30 each have a switching pin 52 extending through them, and they can be adjusted circumferentially relative to the output element 20 by rotating them in one direction or the other, and can be brought into engagement with or out of engagement with the drive shaft 2 and the output element 20.On the outside of the output element 20, the form-locking elements are arranged for fixing further output elements or for transmitting power to other components.

[0030] Within the output element 20, receiving pockets 22 are formed which are sawtooth-shaped and enlarge radially in one direction in the circumferential direction. If the switching pins 52 are turned to the right, clockwise, the clamping bodies 32 move to the right and towards an area of ​​the receiving pockets 22 which is at a greater distance from the output section 15 of the drive shaft 2. If the driver 50 with the switching pins 52 is turned to the left, the clamping bodies 32 are pressed against the drive shaft 2 onto the output section 15 by the receiving pockets 22 which taper in the radial direction. If the drive shaft 2 is turned counterclockwise, the clamping bodies 32 clamp themselves between the output section 15 and the receiving pockets 22 of the output element 20 and move the output element 20 counterclockwise.With a reverse clockwise rotation, the clamping elements 32 are moved toward the radially enlarged end of the receiving pockets 22. Due to the increased distance, no clamping effect occurs in this direction and the clamping bodies 32 are disengaged. The clamping bodies 32 can also remain disengaged via the switching pins 52.

[0031] The second freewheel 40 is located axially behind the first freewheel 30 and within the planet carrier 13. The operation of the second freewheel 40 corresponds to that of the first freewheel 30, only with the opposite direction of rotation.

[0032] Figure 3 shows the gearbox without the housing and with the planetary carrier components in the assembled state. The driver 50 is mounted on the bearing, and the shift pins extend through both the clamping bodies of the first and second freewheels.

[0033] Figure 4 shows the gearbox without the ring gear. It can be seen that the planetary gears 12 are rotatably mounted on pins on the planetary carrier 13 and transmit the torque from the sun gear 11 to the ring gear (not shown) through the external gearing or through a force-locking transmission. By rolling on the inner circumference of the ring gear, the planetary carrier 13 is rotated at a lower speed than the drive shaft 2.

[0034] Figure 5 shows a front view of an embodiment similar to Figure 2, wherein not all clamping bodies 32 of the first freewheel 30 are shown in order to allow a view of the clamping bodies 42 of the second freewheel 40. The clamping bodies 32, 42 of the two freewheels 30, 40 are arranged on the switching pins 52, which protrude perpendicularly into the plane of the drawing. All switching pins 52 are connected to one another via the driver 50 (not shown) and synchronize the adjustment movement of all clamping bodies 32, 42. Elongated holes 320, 420 are arranged in all clamping bodies 32, 42, which enable a movement of the clamping bodies 32, 42 radially outwards as well as a tilting about the switching pins 52.In the embodiment of Figure 5, the receiving pockets 22 are provided with a contour that increases radially in one direction of rotation, wherein the clamping bodies 32, 42 have an outer contour that corresponds to the contour of the receiving pockets 22, but is radially enlarged. The receiving pockets 22 increase in size in the radial direction, depending on the respective angular position. In the axial direction, the receiving pockets 22 are the same for all cutting surfaces in the axial extension. The receiving pockets 22 for the first freewheel 30 can also be thread-like and taper in the axial direction, so that when the switching pins 52 are rotated counterclockwise, the clamping bodies 32 are rotated to the left relative to the output element 20, whereby the clamping bodies 32 are additionally moved perpendicular to the blade plane.In all versions, the clamping bodies are pressed towards the outside of the output section 15 due to the diameter reductions of the sawtooth-like receiving pockets 22.

[0035] The radial mobility is provided by the elongated holes 320 in the clamping bodies 32. As soon as the surface of the clamping body 32 facing the output section 15 comes into contact with the output section 15 of the drive shaft 2, the clamping body 32 is rotated and pivoted about the longitudinal extent of the switching pin 52, which is indicated by the arrow 321. As a result, the clamping body 32 clamps itself to the output element 20 and the drive shaft 2 and, in this embodiment, also moves the output element 20 clockwise when the drive shaft moves clockwise. In addition, the output element 20 rotates counterclockwise when the drive shaft moves counterclockwise, provided that the clamping bodies 32 rest with their inwardly directed surfaces on the output section 15 and the switching pins 52 allow sufficient radial displacement inwards.

[0036] The clamping bodies 42 of the second freewheel 40 are designed to correspond and are oriented in opposite directions. In the illustrated position of the switching pins 52, they are disengaged from the outer side 1333 of the sleeve portion 133 of the planetary carrier 13 and thus cannot transmit any forces or torques. Upon a reversal of the direction of rotation and a corresponding switching position of the switching pins 52, the clamping bodies 42 of the second freewheel 40 are brought into contact with the planetary carrier 13 and transmit the drive power of the drive to the output element 20 at a lower speed and a higher torque.

[0037] A variant of the manual transmission is shown in Figure 6, which corresponds in its basic structure to the manual transmission in Figure 5. In Figure 6, the two oppositely oriented, sawtooth-shaped outer surfaces of the receiving pockets 22, which expand radially outwards in different directions, can be seen. In the exemplary embodiment according to Figure 6, the clamping bodies 32, 42 are designed as rollers; the receiving pockets 22 do not have spirally tapered contact surfaces, but are oriented essentially parallel to the longitudinal extent of the switching pins 52. Upon rotation of the output section 15 of the drive shaft 2, the clamping bodies 32 of the first freewheel are pressed against the tapered surfaces of the receiving pockets 22 and move the output element 20 counterclockwise.When the output section 15 rotates clockwise, the clamping bodies 32 of the first freewheel 30 are displaced towards the enlarged end of the receiving pockets 22 due to the elongated hole, roll on the switching pins 52 if necessary, and do not transmit any forces to the output element 20. In contrast, the clamping bodies 42 of the second freewheel 40 engage with the outer side 1333 of the sleeve section of the planet carrier 13 and clamp the output element 20, resulting in a clockwise adjustment movement of the output element 20. By changing the direction of rotation, the other freewheel is activated or deactivated. The two freewheels 30, 40 are coupled via the switching pins 52 of the driver 50.If no active adjustment of the switching pins 52 is to take place via a motor or other controlled drive, it should be ensured that a starting position of a freewheel is always present by default, so that one freewheel is always engaged and one freewheel is always disengaged. For this purpose, the switching pins 52 or the driver 50 can be preloaded with a spring which, for example, always loads the first freewheel in a direction in which it engages and always keeps the second freewheel disengaged, or vice versa. The preload force is overcome by the clamping bodies if a corresponding direction of rotation of the drive shaft 2 is present. In such a standard setting, complete decoupling of drive and output is not possible.Such complete and permanent decoupling is achieved via the actuator 80 during active adjustment by assuming a central position of the switching pins 52 so that no forces can be transmitted from the drive shaft 2 to the output element 20. Such a central position is preferably only possible for a small adjustment range of the driver 50 in order to enable rapid switching and activation of the manual transmission. By actively decoupling or uncoupling the manual transmission, the drive can be completely separated from the orthopedic device. This makes it possible to provide a purely passive mode of the orthopedic device, for example, when both an active drive and a passive influence on the movement behavior of the orthopedic component are provided, for example via a hydraulic damper.Decoupling will also reduce noise, as there will be no motor or gear noise in addition to the noise of the orthopedic device with a purely passive resistance device. Reference symbol list.

[0038] 2 - Drive shaft

[0039] 10 - Planetary gear

[0040] 11 - Sun gear

[0041] 12 - Planetary gears

[0042] 13 - Planet carrier

[0043] 14 - Ring gear

[0044] 15 - Output section

[0045] 20 - Output element

[0046] 22 - Recording pockets

[0047] 24 - Inside

[0048] 30 - Freewheel

[0049] 32 - Clamping body

[0050] 40 - Freewheel

[0051] 42 - Clamping body

[0052] 50 - Driver

[0053] 52 - Switch pins

[0054] 60 - Warehouse

[0055] 80 - Actuator

[0056] 110 - External gearing

[0057] 120 - External gearing

[0058] 133 - Sleeve section

[0059] 140 - Internal gearing

[0060] 320 - Long hole

[0061] 420 - Long hole

[0062] 1333 - Outside

Claims

Patent claims 1. A gearbox for orthopaedic devices with a planetary gear (10) having a central sun gear (11), with a plurality of planetary gears (12) which are rotatably mounted on a planetary carrier (13) and are coupled to the sun gear (11) in a force-transmitting manner, and with a ring gear (14) which has an inner circumference in which the planetary gears (12) rotate, the sun gear (11) is coupled to a drive shaft (2) and the planetary carrier (13) is coupled to an output element (20), characterized in that the output element (20) is coupled to two oppositely oriented, switchable freewheels (30, 40), wherein in a first direction of rotation of the drive shaft (2), a first freewheel (30) can be brought into direct force-transmitting engagement with the drive shaft (2), and in a second direction of rotation of the drive shaft (2) opposite to the first direction of rotation, a second Freewheel (40) can be brought into engagement with the planet carrier (13) in a force-transmitting manner,to drive the output element (20)., 2. Manual transmission according to claim 1, characterized in that the freewheels (30, 40) have clamping bodies (32, 42) which, in an engaged position, engage with the output element (20) and the drive shaft (2) or the planet carrier (13) in a force-transmitting manner, the clamping bodies (32, 42) are assigned switching pins (52) which move the clamping bodies (32, 42) from the engaged position into a release position in which the clamping bodies (32, 42) are disengaged, and back.

3. Manual transmission according to claim 2, characterized in that the switching pins (52) are arranged on a rotatably mounted driver (50).

4. Gearbox according to claim 2 or 3, characterized in that the freewheels (30, 40) are arranged coaxially and axially one behind the other and at least one switching pin (52) a clamping body (32) for the first freewheel (30) and a clamping body (42) for the second freewheel (40) are arranged.

5. Manual transmission according to claim 3 or 4, characterized in that the driver (50) is coupled to an actuator (80).

6. Manual transmission according to one of claims 3 to 5, characterized in that the clamping bodies (32, 42) and the driver (50) are designed to hold all clamping bodies (32, 42) in the release position.

7. Manual transmission according to one of the preceding claims, characterized in that the clamping bodies (32) of the first freewheel (30) are arranged between an output section (15) arranged or formed on the drive shaft (2) and an inner side (24) of the output element (20).

8. Manual transmission according to one of the preceding claims, characterized in that the output element (20) is rotatably mounted in an inner circumference of the planet carrier (13) and the clamping bodies (42) of the second freewheel (40) are arranged between an inner side of the output element (20) and an outer side (1333) of a sleeve section (133) of the planet carrier (13).

9. Manual transmission according to one of the preceding claims, characterized in that the planetary gear (10) is designed as a friction gear or gear transmission with external toothings (110, 120) for the sun gear (11) and the planet gears (12) and an internal toothing (140) for the ring gear (14).

10. Manual transmission according to one of the preceding claims, characterized in that receiving pockets (22) for the clamping elements (32, 42) are formed in the output element (20) which radially enlarge in the circumferential direction and the enlargement of the receiving pockets (22) for the clamping elements (32) of the first freewheel (30) runs opposite to that of the second freewheel (40).

11. Manual transmission according to claim 2, characterized in that the clamping bodies (32, 42) have elongated holes (320, 420) for receiving the switching pins (52).

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