Electromagnetically shiftable positive engagement clutch and position determination method

Abstract

To provide an electromagnetically shiftable active engagement clutch.SOLUTION: An electromagnetically shiftable positive engagement clutch is disposed on the shaft for rotation therewith and has a movable portion linearly displaceable between a clutch engaged position and a clutch disengaged position. The positive-engagement clutch comprises a stationary part and a stator with an energizable drive coil (30) for adjusting the movable part along the shaft, wherein, in a clutch-engaged position, a positive engagement is formed between the movable part and the stationary part and a rotational connection is formed. A sensor device (42) is provided which is arranged adjacent to the movable part and has a Hall sensor (44) and a magnet (46) which magnetically surrounds the Hall sensor (44). A sensor arrangement (42) is arranged axially or radially spaced from the movable part and is configured to detect axial movement of the movable part via a change in magnetic field line angle of a magnetic field generated by a magnet (46).SELECTED DRAWING: Figure 6A

Description

[Technical Field]

[0001] The present invention relates to an electromagnetically shiftable, positively engaging clutch. Additionally, the present invention relates to a method for determining the position of an axially movable part of an electromagnetically shiftable, positively engaging clutch. [Background technology]

[0002] Clutches are commonly used to temporarily transfer torque from one shaft to another coaxially aligned shaft without permanently connecting the two shafts. A distinction is made here between frictional engagement clutches and active engagement clutches. The present invention relates to actively engaging clutches, referred to herein as active engagement clutches. Active engagement clutches include, for example, toothed clutches and dog clutches that engage in a form-fit manner to transmit torque.

[0003] Positive engagement clutches often use a displaceable shift sleeve that includes one or more different teeth that form-fit together to provide positive engagement and allow torque transmission from the first shaft to the second shaft.

[0004] The prior art discloses an electromagnetic clutch in which the shift sleeve is adjusted by a drive coil that applies a magnetic force to the shift sleeve. In this type of clutch, the shift sleeve can be moved in one direction from a disengaged position to engage the shift sleeve with the clutch body. This is called an overrunning clutch.

[0005] Additionally, double sided clutches are known in which the shift sleeve can be moved in opposite directions from a disengaged position to engage different axially spaced clutch bodies.

[0006] In particular, in an electromagnetically shiftable, actively engaging clutch, a control unit is provided that controls the displacement of the shift sleeve by means of a control command. To optimize the clutch operating process, it is necessary to know the current position, i.e., the engagement position, of the shift sleeve. This is because, for each control command sent to the electromagnetically shiftable, actively engaging clutch, the current engagement state must first be analyzed so that the control unit can query the position of the shift sleeve at any time. DISCLOSURE OF THE INVENTION [Problem to be solved by the invention]

[0007] In the prior art, the shift state or engagement position of the shift sleeve is determined by indirect measurements such as the current state of the stator or the speed of the connected shaft.

[0008] Similarly, it is known to use Hall sensors for position detection, which detect position based on changes in a magnetic field, but the sensor devices required for this are complex and require a relatively large installation space.

[0009] It is also possible to use a switch to detect the end positions of the shift sleeve, i.e., the engaged or disengaged position of the shift sleeve, where the switch is actuated by a dedicated actuating element when the shift sleeve is in the engaged position.

[0010] Instead of a switch, a displacement measurement system could also be used, which would also operate via additional components.

[0011] The methods known in the prior art for detecting the position of the shift sleeve are characterized by the fact that they involve indirect measurements and require the scanning or actuation of additional components, making it impossible to directly and accurately detect the actual clutch engagement position and always requiring additional components.

[0012] Additionally, the position of the shift sleeve is typically sensed axially, increasing the installation space required for a positive engagement clutch.

[0013] Furthermore, the additional parts and installation space required increase the manufacturing costs of positive engagement clutches.

[0014] Furthermore, these measurement techniques often require precise calibration of the sensor to the measurement point, which is usually very complex and therefore costly. [Means for solving the problem]

[0015] It is therefore an object of the present invention to provide an electromagnetically shiftable active engagement clutch in which the engagement position is determined very quickly and accurately by direct measurement, while minimizing the installation space and number of parts required, and to provide a method for determining the engagement position in such a way that the position is determined as accurately as possible.

[0016] This object is achieved by an electromagnetically shiftable active engagement clutch according to the present invention, which includes an axially movable driven part mounted on a shaft, rotating with the shaft, and linearly displaceable along the shaft between a clutch-engaged position and a clutch-released position. The active engagement clutch further includes at least one axially fixed part to be driven, coaxially aligned with the shaft, and a stator having at least one energizable drive coil for adjusting the movable part along the shaft, such that in the clutch-engaged position, active engagement occurs between the movable part and the fixed part, thereby creating a rotational connection between the shaft and the fixed part. The active engagement clutch further includes a fixed sensor device disposed adjacent to the movable part, the fixed sensor device including at least one Hall sensor and at least one magnet disposed adjacent to the at least one Hall sensor and permanently fixed relative to the at least one Hall sensor. The sensor device is disposed axially or radially spaced apart from the movable part, and the Hall sensor is configured to detect axial movement of the movable part through a change in the angle of the magnetic field lines generated by the magnet.

[0017] In other words, at least one Hall sensor is positioned within the magnetic field of the magnet in the active engagement clutch. The Hall sensor detects changes in the magnetic field angle due to axial movement of the moving part, and the control unit can determine the engagement position of the moving part based on this data. Because this is a direct measurement, no additional components are required, reducing manufacturing costs. Furthermore, Hall sensors used to measure the magnetic field angle are commonly used sensors that are available at low cost, have fast response, and require minimal space. Therefore, a sensor device equipped with a Hall sensor can detect the exact position of the moving part without or independently of coil current.

[0018] Therefore, the position of the moving part is determined by measuring the change in the angle of the magnetic field lines, which can be measured based on the Hall effect. This means measuring the change in voltage across a current conductor placed within the magnetic field. The change in the magnetic field due to the axial movement of the moving part results in exactly this voltage change, which can be used to detect the change in the magnetic field line angle. Because the Hall sensor is magnetically surrounded by at least one magnet, it can prevent or reduce the influence of the magnetic field of the drive coil, which could lead to uncontrollable changes in the Hall effect. Furthermore, this arrangement eliminates the need for a permanent magnet fixed to the moving part. This significantly reduces manufacturing costs, as ring-shaped permanent magnets suitable for moving parts are custom-made and typically significantly increase manufacturing costs. Furthermore, because the magnetic field line angle can be detected with an accuracy of up to several millidegrees (m°), the sensor device can provide more accurate results for detecting the position of the moving part.

[0019] The moving part may be a shift sleeve or an armature and the fixed part may be in the form of a clutch body, wherein the armature and / or the shift sleeve are preferably made of a ferromagnetic metal.

[0020] Preferably, the Hall sensor includes an evaluation unit configured to determine the field line angle of the magnetic field generated by the magnet. Furthermore, the evaluation unit can be configured to send the determined field line angle to a control unit of the electromagnetically shiftable active clutch. Therefore, the evaluation unit, preferably in the form of a microprocessor, is integrated into the sensor device, preferably directly into the Hall sensor. This allows the Hall sensor to directly output the field line angle without the field line angle having to be first determined by the control unit of the active clutch.

[0021] Therefore, it is preferable to install Hall sensors with integrated evaluation units. However, alternatively, conventional Hall sensors connected to a microprocessor and / or control unit can be used, with the microprocessor and / or control unit calculating the magnetic field line angle. If the Hall sensors are connected to a microprocessor, it is preferable to also integrate the microprocessor into the sensor device. This allows for the integration of a unit consisting of the Hall sensors, the microprocessor, and preferably the control unit.

[0022] According to one embodiment, the Hall sensor has two measurement points, which allows for more accurate results of the magnetic field line angle, and therefore more accurate calculation of the position of the moving part.

[0023] According to a further embodiment, the sensor device includes two magnets, with the Hall sensor positioned between them. The presence of two magnets allows for a stronger magnetic field to be generated in the area where the Hall sensor is located. Because the magnetic field of two magnets is stronger than that of a single magnet, the presence of two magnets also results in a greater change in the angle of the magnetic field lines, again resulting in more accurate measurement results. Furthermore, the presence of two magnets allows for better shielding of the Hall sensor from the stator's magnetic field, amplifying the signal provided by the Hall sensor and achieving a higher overall resolution.

[0024] Preferably, the two magnets have magnetic axes that are diagonally positioned relative to the central axis of the Hall sensor. The magnetic axes face each other and are positioned at an acute angle relative to the central axis. Preferably, the acute angle is less than 45 degrees. The asymmetrical positioning of the magnetic axes provides optimal orientation of the magnetic field, thereby generating a strong magnetic field for measuring magnetic field line angles, particularly changes in magnetic field line angle, as accurately as possible.

[0025] In a preferred embodiment, the magnet is a permanent magnet or an electromagnet, which are therefore commonly used magnets, readily available and therefore cost effective.

[0026] According to a further embodiment, the sensor device comprises at least two Hall sensors, each of which is preferably assigned at least one magnet adjacent to the corresponding Hall sensor. In this way, additional measurement points can be provided, which can improve the measurement accuracy and / or the measurement result and thus provide a higher resolution for determining the position of the moving part.

[0027] Preferably, the sensor device is housed in a sensor housing attached to the stator housing, thus avoiding installation space issues as the sensor does not need to be located between the moving part and the fixed part or immediately adjacent to or on the fixed part.

[0028] The sensor housing is preferably made from a plastic material and is provided with a holder that can be used to fasten the sensor housing to the stator housing, for example by screwing, gluing, welding or riveting the holder to the stator housing.

[0029] According to a preferred embodiment, at least two sensor devices are provided, the at least two sensor devices being circumferentially offset from one another, which allows for early detection of uneven displacement of the movable part (e.g. due to tilting of the movable part), and thus allows for controlling the movable part to suppress the tilting movement and for a rapid disengagement and re-engagement process to be carried out in a short time.

[0030] In yet another embodiment, each magnet is provided with a magnetically soft material, which is located next to the magnet on the side opposite the Hall sensor or underneath the magnet on the side facing the moving part. The magnetically soft material serves to guide the magnetic flux, amplifying the Hall sensor signal and preventing undesired changes in the Hall effect due to the magnetic field generated by the stator. The magnetically soft material thus provides additional shielding from the magnetic field of the drive coil and amplifies the magnetic field of the magnets located within the sensor device, resulting in the largest possible change in the angle of the magnetic field lines.

[0031] In accordance with the present invention, the above objects are also achieved by a method for determining the position of a movable part of an electromagnetically shiftable, positively engageable clutch, the method comprising the steps of: - detecting a Hall voltage using a Hall sensor; - calculating the magnetic field line angle by means of an evaluation unit integrated in the Hall sensor; - sending the magnetic field line angle to a control of an electromagnetically shiftable active engagement clutch; - assigning, using the control unit, a unique position for the movable part based on the calculated magnetic field line angle.

[0032] The basic idea is therefore that the position determination is based on the change in the magnetic field line angle, which change is passed on to the control by the sensor device, so that the position of the movable part can be determined as accurately as possible.

[0033] As already mentioned, axial movement of the moving part causes a change in the magnetic field. This in turn changes the magnetic flux passing through the Hall sensors, resulting in a Hall voltage. Based on the Hall voltage, an evaluation unit, for example implemented by a microprocessor, can determine the angle of the magnetic field lines and send it to the control unit.

[0034] Alternatively, the position of the moving part can be determined by multiple Hall sensors, in particular Hall sensors offset from one another along the circumference of the stator. The positions determined by the multiple Hall sensors are compared with one another by the control of the positive clutch. This allows an incorrect position of the moving part to be corrected as quickly as possible, for example by appropriately controlling the positive clutch or by briefly disengaging and reengaging it.

[0035] In a further development, the magnetic field line angle is determined for each position of the movable part of the electromagnetically shiftable active engagement clutch, so that the current position of the movable part is always stored in the control of the active engagement clutch, and all clutch actuation processes can be carried out in an optimized manner and without delay. [Brief explanation of the drawings]

[0036] [Figure 1] FIG. 1 is a cross-sectional view of an electromagnetically switchable, active engagement clutch according to the present invention, showing the switch sleeve in a disengaged position. [Figure 2] FIG. 2 shows a partial perspective view of the mounting area of ​​the sensor device of the positive engagement clutch shown in FIG. [Figure 3] FIG. 3 shows a detailed perspective view of the sensor device shown in FIG. [Figure 4] FIG. 4 is a schematic cross-sectional view of the sensor device shown in FIGS. [Figure 5] FIG. 5 is a more detailed perspective view of the sensor device shown in FIGS. [Figure 6A] FIG. 6A shows a schematic diagram of the clutch operation process, particularly showing the clutch release position. [Figure 6B] FIG. 6B shows a schematic diagram of the clutch operation process, particularly showing the intermediate position. [Figure 6C] FIG. 6C shows a schematic diagram of the clutch operation process, particularly showing the clutch engaged position. [Figure 7A] FIG. 7A shows a schematic diagram of the magnetic field in different engagement positions, and in particular the magnetic field in the clutch disengagement position shown in FIG. 6A. [Figure 7B] FIG. 7B shows a schematic diagram of the magnetic field in different engagement positions, and in particular the magnetic field in the clutch engagement position shown in FIG. 6C. [Figure 8] FIG. 8 shows a detailed schematic diagram of the magnetic field shown in FIG. 7A. [Figure 9] FIG. 9 shows a second configuration of a sensor device that can be used in the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0037] Further advantages and features of the present invention will become apparent from the following description and the referenced drawings. Figure 1 shows an electromagnetically shiftable, positively engageable clutch 10 that functions to couple a first shaft 12 and a second shaft 14 coaxially disposed therewith through opening and closing movements.

[0038] The positively engageable clutch 10 shown in FIG. 1 is an electromagnetic toothed clutch with teeth that project radially inward and radially outward and intermesh with each other.

[0039] However, the electromagnetically shiftable, positively engaging clutch 10 may be any other type of toothed clutch, it being only important that the connection be established by positive engagement.

[0040] The electromagnetically shiftable active engagement clutch 10 includes an axially movable driven part 15, which in an exemplary embodiment of the active engagement clutch 10 is a shift sleeve 16 having a first tooth 18 disposed laterally along its circumference.

[0041] Furthermore, a shift sleeve 16 is disposed on the first shaft 12 for rotation therewith and is axially adjustable between a clutch-engaged position and a clutch-disengaged position along teeth 19 connecting the shaft 12 and the shift sleeve 16. Figure 1 shows the shift sleeve 16 in the disengaged position.

[0042] The second shaft 14 is provided with a driven axial fixed portion 21, and in the exemplary embodiment of this active engagement clutch 10, the clutch body 20 is a single clutch body 20 connected to the second shaft 14 so as to rotate together.

[0043] The clutch body 20 includes second teeth 22 arranged along the outer periphery of the clutch body 20. Furthermore, the clutch body 20 is arranged coaxially with the first shaft 12.

[0044] However, it is also conceivable that the clutch body 20 forms part of the second shaft 14 and is formed integrally therewith.

[0045] The first toothing 18 and the second toothing 22 together form a clutch tooth system 24 which serves to provide a positive engagement between the shift sleeve 16 and the clutch body 20 when the shift sleeve 16 is in the engaged position.

[0046] The clutch tooth system 24 formed by the first toothing 18 and the second toothing 22 may have undercuts on at least the teeth of the first toothing 18 and / or the teeth of the second toothing 22, the undercuts being configured such that when the shift sleeve 16 is in the clutch-engaged position and torque is applied to the active engagement clutch 10, the circumferential force is converted into an axial displacement force, thereby displacing the shift sleeve 16 further toward the clutch body 20. This can be achieved, for example, by the undercuts widening in a wedge shape, creating a wedge effect in the direction of the clutch's engaged position when torque is transmitted.

[0047] Additionally, a stator 26 is provided that includes a stator housing 28 and a drive coil 30 at least partially contained within the stator housing 28 .

[0048] The stator housing 28 includes a housing pot 32 that extends around the circumference of the drive coil 30 and along the front face of the drive coil 30 .

[0049] The stator housing 28 further includes a housing ring 34 that extends along the circumference of the drive coil 30 and also extends to the front side of the drive coil 30 opposite the housing pot 32 .

[0050] The drive coil 30 is used to linearly adjust the shift sleeve 16 along the first shaft 12 to the clutch body 20 toward an engaged position.

[0051] Alternatively, it is contemplated that the drive coil 30 may be used to adjust the shift sleeve 16 along the first shaft 12 toward the release position.

[0052] The adjustment of the shift sleeve 16 is performed by utilizing a magnetic force that acts on the shift sleeve 16 when the drive coil 30 is energized.

[0053] In order to return the shift sleeve 16 to the release position, an elastic spring unit 40 is provided, and by means of this elastic spring unit 40 the shift sleeve 16 is connected to the first shaft 12 in an axially displaceable state.

[0054] The elastic spring unit 40 is disposed between the shift sleeve 16 and the first shaft 12, and when the shift sleeve 16 moves axially relative to the first shaft 12 toward the clutch engagement position, the elastic spring unit 40 is compressed. This generates a restoring force that the first elastic spring unit 40 exerts on the shift sleeve 16.

[0055] This restoring force acts against the magnetic force of the drive coil 30 .

[0056] The elastic spring unit 40 is arranged in a recess in the shaft 12 and presses axially against the wall of the shaft 12 on the one hand and against a disk 41 fixed to the shift sleeve 16 on the other hand.

[0057] Therefore, the elastic spring unit 40 is housed in a space surrounded by the first shaft 12 on the radial inside and the shift sleeve 16 on the radial outside.

[0058] The spring unit 40 may preferably be a wave spring or wave spring assembly.

[0059] As can be seen particularly in the detailed views of FIGS. 2 and 3, the first embodiment of the active engagement clutch 10 shown here further includes a sensor device 42.

[0060] As can be particularly seen in FIGS. 3 to 5, the sensor device 42 includes at least one Hall sensor 44 and a fixed magnet 46 disposed laterally of the Hall sensor 44 .

[0061] Preferably, the Hall sensor 44 has two measurement points 45 (see FIG. 7A) to ensure the most accurate position measurement possible.

[0062] The magnet is a permanent magnet or an electromagnet used to provide a stable magnetic field M to the Hall sensor 44. For this purpose, the magnet 46 is arranged so as to be permanently fixed in the vicinity of the Hall sensor 44.

[0063] In order to make the magnetic field M as strong as possible and to optimally position the Hall sensor 44 within the magnetic field M, the magnet 46 is preferably positioned at an angle to the central axis A of the Hall sensor 44 .

[0064] In particular, it can be seen in FIG. 8 that the intensities I1, I2, I3, I4, I5 of the magnetic field M decrease with increasing distance from the magnet 46.

[0065] As can be seen particularly clearly in FIG. 4, the Hall sensor 44 is connected via three lines 52 to a control 56 of the active clutch 10 .

[0066] The Hall sensor 44 has an integrated evaluation unit 47, which may be, for example, a microprocessor.

[0067] The sensor device 42 is laterally fixed to the stator housing 28, as can be seen particularly in FIG.

[0068] The sensor housing 48 may be secured to the stator housing 28 by fastening means such as a holder 50 and / or screws, for example. Alternatively, the sensor housing 48 may be glued or riveted to the stator housing 28.

[0069] The sensor device 42 is fixed radially or axially to the stator housing 28 and spaced from the shift sleeve 16 so that the engagement position of the shift sleeve 16 can be determined.

[0070] Axial movement of the shift sleeve 16 affects the magnetic field M of the magnet 46, changing the angle of the magnetic field lines of the magnetic field M. The change in the angle of the magnetic field lines is detected by the Hall sensor 44 as a change in the magnetic field M and a change in the magnetic flux.

[0071] The function and operation of the active engagement clutch 10 and the detection of the engagement position of the shift sleeve 16 using the sensor device 42 will now be described.

[0072] In this initial state, the shift sleeve 16 is in the release position, as shown in FIGS.

[0073] There is no active engagement between the first teeth 18 of the shift sleeve 16 and the second teeth 22 of the clutch body 20 .

[0074] In this released state, the shift sleeve 16 is held by the elastic spring unit 40 unless an external force exceeding the force of the spring unit 40 acts on the shift sleeve 16 .

[0075] This is also referred to as a "normally open" positive engagement clutch 10.

[0076] As long as the shift sleeve 16 is in the release position, the magnetic field M does not change and a constant magnetic field line angle α is detected by the Hall sensor 44 of the sensor device 42 .

[0077] In addition to a change in the field line angle α, a change in the magnetic field M also leads to a change in the strength of the magnetic flux, i.e., the magnetic flux intensity, which results in a Hall voltage being detected by the Hall sensor 44. The evaluation unit 47 can determine the field line angle α based on this Hall voltage.

[0078] While the shift sleeve 16 is in the released position, the magnetic field M does not change, but the Hall sensor 44 is in the magnetic flux that generates a Hall voltage, so the magnetic field line angle α can be determined even without axial displacement, i.e., regardless of whether the shift sleeve 16 is moving or not.

[0079] When the shift sleeve 16 is to be moved from the released position toward the clutch body 20, it is first necessary to apply a sufficient voltage to the drive coil 30.

[0080] The energization of the drive coil 30 is performed by a control unit 56 which controls the clutch operation process and processes the signals of the sensor device 42 (see FIG. 4).

[0081] Therefore, the control unit 56 is connected to both the drive coil 30 and the sensor device 42, and the control unit 56 and the sensor device 42 are connected to each other at least in terms of signal transmission.

[0082] The connection between the control unit 56 and the sensor device 42 is preferably made by a cable, a line 52, and / or a plug.

[0083] When the drive coil 30 is energized, a magnetic flux is generated, and a magnetic force acts on the shift sleeve 16 in the direction of the clutch body 20 .

[0084] When the amount of magnetic force exceeds the amount of force acting on the shift sleeve 16 through the spring unit 40 , the shift sleeve 16 moves toward the clutch body 20 .

[0085] As the shift sleeve 16 is displaced, the magnetic field M of the magnet 46 changes, and the angle of the magnetic field lines relative to the Hall sensor 44 also changes.

[0086] A change in the magnetic field M results in a change in the magnetic flux, which in turn causes a change in the Hall voltage detected by the Hall sensor 44. Based on this Hall voltage, the control and evaluation unit 47 can deduce the magnetic field line angle α.

[0087] The evaluation unit 47 passes the determined field line angle α back to the control unit 56, which can assign a specific position to the shift sleeve 16 on the basis of the field line angle α.

[0088] 6B, the shift sleeve 16 is ultimately positioned in the clutch engaged position shown in Figures 6C and 7B. When the drive coil 30 is energized, a magnetic holding force acts on the shift sleeve 16.

[0089] To ensure that all positions of the shift sleeve 16 between the clutch disengaged and clutch engaged positions can be reliably determined, the shift sleeve 16 is preferably made of a ferromagnetic material.

[0090] In the clutch engaged position, the first toothed portion 18 and the second toothed portion 22 mesh with each other, creating a positive engagement between the shift sleeve 16 and the clutch body 20 .

[0091] While the shift sleeve 16 is in the clutch-engaged position, the gap between the sensor device 42 and the shift sleeve 16 does not change, and therefore the Hall sensor 44 cannot detect a change in the Hall voltage.

[0092] To return the shift sleeve 16 to the clutch disengaged position, it is first necessary to reduce or stop the magnetic force generated by energizing the drive coil 30.

[0093] When the magnetic force acting on the shift sleeve 16 is smaller than the restoring force of the elastic unit 40 acting on the shift sleeve 16, the shift sleeve 16 returns from the clutch-engaged position to the clutch-disengaged position.

[0094] In this state, the shift sleeve 16 is held in place by the force of the elastic unit 40 .

[0095] When the shift sleeve 16 is displaced from the clutch engagement position to the clutch release position, the magnetic field M changes again due to the axial movement of the shift sleeve 16, and the magnetic field line angle α is again detected by the sensor device 42 via the Hall voltage associated with the change in magnetic flux.

[0096] In an embodiment not shown, the sensor device 42 may include a magnetically soft material arranged next to the magnet 46 on the side opposite the Hall sensor 44 or below the magnet 46 on the side facing the shift sleeve 16 or the movable part 15.

[0097] The inclusion of such a magnetically soft material in association with magnet 46 can guide the magnetic flux of magnet 46 and strengthen the magnetic field M, thereby preventing or minimizing undesired changes in the Hall effect due to the magnetic field of drive coil 30. Furthermore, as a stronger magnetic field M is applied, the change in magnetic field line angle α also increases.

[0098] The magnetically soft material may be, for example, a ferromagnetic metal or metal oxide.

[0099] Also, in an embodiment not shown, the positive engagement clutch 10 is equipped with two sensor devices 42 .

[0100] The design of the sensor device 42 and the method for detecting the position of the shift sleeve 16 remain unchanged here.

[0101] In an embodiment of the active engagement clutch 10 having two sensor devices 42, the sensor devices 42 are circumferentially offset from one another, but preferably the two sensor devices 42 are not offset 180 degrees from one another.

[0102] By detecting the engagement position of the shift sleeve 16 using at least two sensor devices 42, it is possible to detect not only the current engagement position but also whether the shift sleeve 16 is slightly tilted.

[0103] If so, the controller 56 can output appropriate control commands to reorient the shift sleeve 16 perpendicular to the first shaft 12 .

[0104] FIG. 9 shows a further embodiment of a sensor device 42 which can also be used to detect the engagement position of the shift sleeve 16 .

[0105] The sensor device 42 shown here comprises two magnets 46, each having a magnetic axis B, arranged obliquely relative to the central axis A of the Hall sensor 44. Here, the magnetic axes B face each other and are arranged at an acute angle relative to the central axis A.

[0106] Preferably, the two magnets 46 are arranged asymmetrically with respect to the central axis A, and the angles between the magnetic axes B and the central axis A are each less than 45 degrees.

[0107] Such an arrangement of the magnets 46 allows the strongest possible magnetic field M to be generated, and changes in the magnetic field M result in large changes in the magnetic field lines. This allows the signal detected by the Hall sensor 44 to be amplified, thereby achieving higher resolution.

[0108] In another embodiment, not shown, the sensor arrangement 42 comprises at least two Hall sensors 44, each associated with a magnet 46. Using two Hall sensors 44 allows the magnetic field line angle to be measured at multiple points, resulting in more accurate results and thus a more precise determination of the position of the shift sleeve 16.

[0109] In another embodiment, the sensor device 42 includes at least two Hall sensors 44, but in this case, each Hall sensor 44 does not have its own dedicated magnet 46 associated therewith.

[0110] Although the figures illustrate a positively engageable clutch 10 having one clutch body 20, the sensor devices 42 may be mounted on both sides of the positively engageable clutch 10.

[0111] Alternatively, the positive engagement clutch 10 may include two sensor devices 42, one for each side of the shift sleeve 16.

[0112] The illustrated positively engageable clutch 10 is unique in that no additional components are required to be attached to the shift sleeve 16 to sense the position of the shift sleeve 16.

Claims

1. a movable part (15) disposed on the shaft (12) so as to rotate integrally with the shaft (12) and driven so as to move linearly along the shaft (12) between a clutch engagement position and a clutch release position; at least one driven, axially fixed stationary part (21) coaxially aligned with said shaft (12); a stator (26) having at least one energizable drive coil (30) for adjusting the movable part (15) along the shaft (12); a fixed sensor device (42) arranged adjacent to the movable part (15) and comprising at least one Hall sensor (44) and at least one magnet (46) arranged adjacent to the at least one Hall sensor (44) and permanently fixed relative to the at least one Hall sensor (44); Equipped with In the clutch engagement position, there is an active engagement between the movable part (15) and the fixed part (21), and thus a rotational connection between the shaft (12) and the fixed part (21); The sensor device (42) is arranged axially or radially at a gap from the movable part (15), and the Hall sensor (44) is configured to detect displacement of the movable part (15) through changes in the magnetic field line angle (α) of the magnetic field (M) generated by the magnet (46).

2. 2. The electromagnetically shiftable active engagement clutch (10) according to claim 1, further comprising an evaluation unit (47) integrated into the Hall sensor (44), the evaluation unit (47) being configured to determine the magnetic field line angle (α) of the magnetic field (M) generated by the magnet (46) and transmit it to a control unit (56) of the electromagnetically shiftable active engagement clutch (10).

3. 3. An electromagnetically shiftable active engagement clutch (10) according to claim 1 or 2, characterized in that the Hall sensor (44) has two measurement points, in particular the magnetic field line angle (α) corresponds to the average value of the two measurement points.

4. 4. The electromagnetically shiftable active engagement clutch (10) according to claim 1, wherein the sensor device (42) comprises two of the magnets (46), and the Hall sensor (44) is disposed between the two magnets (46).

5. 5. The electromagnetically shiftable active engagement clutch (10) of claim 4, wherein the two magnets (46) each have a magnetic axis (B) that is disposed obliquely with respect to the central axis (A) of the Hall sensor (44), the magnetic axes (B) pointing toward each other and at an acute angle, preferably less than 45 degrees, with respect to the central axis (A).

6. 6. An electromagnetically shiftable, active engagement clutch (10) according to any one of claims 1 to 5, characterized in that the magnet (46) is a permanent magnet or an electromagnet.

7. 7. An electromagnetically shiftable active engagement clutch (10) as claimed in any one of claims 1 to 6, characterized in that the sensor device (42) comprises at least two of the Hall sensors (44), preferably each of the Hall sensors (44) having at least one magnet associated therewith.

8. 8. The electromagnetically shiftable active engagement clutch (10) of claim 1, wherein the sensor device (42) is housed in a sensor housing (48), and the sensor housing (48) is attached to the stator housing (28).

9. 9. The electromagnetically shiftable active engagement clutch (10) according to claim 1, wherein at least two of the sensor devices (42) are provided, and the at least two of the sensor devices (42) are arranged offset from one another in the circumferential direction of the stator (26).

10. The magnet (46) has a magnetically soft material associated therewith, the magnetically soft material being located next to the magnet (46) on the side opposite the Hall sensor (44) or below the magnet (46) on the side facing the moving part (15).

10. An electromagnetically shiftable, active engagement clutch (10) according to any one of claims 1 to 9.

11. 11. A method for determining the position of the movable part (15) of an electromagnetically shiftable active engagement clutch (10) according to any one of claims 1 to 10, comprising: - detecting the Hall voltage using said Hall sensor (44); - calculating the magnetic field line angle (α) by means of an evaluation unit (47) integrated in said Hall sensor (44); - sending the magnetic field line angle (α) to the control (56) of the electromagnetically shiftable active engagement clutch (10); and - assigning a unique position of the mobile part (15) based on the magnetic field line angle (α) calculated by the control part (56); A method comprising:

12. 12. The method according to claim 11, characterized in that the position of the movable part (15) is determined by a plurality of the Hall sensors (44), in particular a plurality of the Hall sensors (44) offset from one another along the circumference of the stator (26), and the determined positions are compared with one another by the control unit (56).

13. 13. A method according to claim 12, characterized in that the magnetic field line angle (α) is determined for each position of the moving part (15) of the electromagnetically shiftable active engagement clutch (10).

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