Actuating device for a vehicle and method for operating an actuating device

Abstract

The approach presented here provides an actuating device (100) for a vehicle. The actuating device (100) comprises a stationary component (105), a rotatable component (110) mounted to rotate relative to the stationary component (105), a magnetorheological medium (115), a coil (120), and a gearbox (125). The magnetorheological medium (115) is arranged in a space (130) between the stationary component (105) and the rotatable component (110) and is configured to provide a first resistance characteristic for movement of the rotatable component (110) relative to the stationary component (105) in a rest state and a second resistance characteristic for movement of the rotatable component (110) relative to the stationary component (105) in an activated state.The coil (120) is configured to generate a magnetic field, the magnetic field being configured to transfer the magnetorheological medium (115) between the rest state and the activation state. The gear unit (125) is coupled to the rotatable component (110) and can be coupled to a user-operated actuator.

Description

[0001] The present invention relates to an actuating device for a vehicle and to a method for operating an actuating device.

[0002] Actuators can be installed in vehicles, for example, to adjust vehicle functions. Some of these actuators may contain a magnetorheological medium or fluid. revelation

[0003] Against this background, the present invention provides an improved positioning device for a vehicle and an improved method for operating a positioning device according to the main claims. Advantageous embodiments are described in the dependent claims and the following description.

[0004] The advantages achievable with the presented approach consist in particular of the fact that an actuating device can be created which amplifies a braking torque provided by means of the actuating device and additionally enables a conversion between rotary and translational motion.

[0005] An actuator for a vehicle comprises a stationary component, a rotatable component mounted to rotate relative to the stationary component, a magnetorheological medium, a coil, and a gearbox. The magnetorheological medium is arranged in a space between the stationary and rotatable components and is configured to provide, in a rest state, a first resistance characteristic for movement of the rotatable component relative to the stationary component, and in an activated state, a second resistance characteristic for movement of the rotatable component relative to the stationary component. The coil is configured to generate a magnetic field, the magnetic field being configured to transfer the magnetorheological medium between the rest and activated states. The gearbox is coupled to the rotatable component and can be coupled to a user-operated actuator.

[0006] The actuator can be a device for operating any vehicle function. The actuator can be designed as a control device, an actuating device, or an actuator. For example, such an actuator can be operated by a vehicle occupant. A rest state of the magnetorheological medium can be understood as a state in which no magnetic field acts on the magnetorheological medium, i.e., the coil is not energized. An activated state of the magnetorheological medium can be understood as a state in which a magnetic field acts on the magnetorheological medium, i.e., the coil is energized.By applying a magnetic field, the viscoelastic or dynamic-mechanical properties of the magnetorheological medium can be changed quickly and reversibly, whereby a deformation of the magnetorheological medium can take place between the rest state and the activation state.

[0007] The approach presented here can also be understood as an MRE actuator (MRE = magnetorheological elastomer) with an upstream gearbox to increase the rotational braking torque, and additionally or alternatively as an MRE actuator with conversion between rotational and translational motion. Depending on the requirements and architecture of the actuator, which can also be referred to as an actuator system, a gearbox can be integrated to amplify the braking effect of the magnetorheological medium, which can also be called a magnetorheological elastomer, in the rotational movement. For haptic actuators, where haptic feedback and reaction time are crucial, the torque of the pure MRE actuator may be sufficient even without a gearbox. However, for actuators where braking torque is important, the torque may only be sufficient with an upstream gearbox.Increasing the braking torque of an actuator using smart materials, such as magnetorheological elastomers, can be achieved by adding a gearbox. Additionally or alternatively, the approach presented here can convert a rotational braking torque into a translational braking force to stop or hold the movement of adjacent components. Another example is a translational haptic movement that can be implemented. This approach can be used in haptic actuators, door actuators, clutches, brakes, linear actuators, tailgate actuators, mechatronic actuators in general, circuits, valves, robotics, dampers, and similar applications.

[0008] Actuators or brake actuators with an integrated gearbox can offer several advantages in terms of braking force, working range, accuracy, service life, and flexibility, making them a preferred choice in many applications. Some advantages of combining a magnetorheological medium with the gearbox are outlined below. A key feature is the coupling of the actuator, which can also be called a rotary MRE actuator, to the gearbox: Increased braking force, as the upstream gearbox can amplify the actuator's torque, resulting in greater braking power. This allows the system to be stopped faster and more effectively. Increased accuracy: The upstream gearbox can improve the accuracy of the brake actuator by transmitting the actuator's torque precisely and evenly to the system being braked. Longer service life: By using an upstream gearbox, the brake actuator can be relieved of stress, which can lead to a longer service life for the components. Greater flexibility: A brake actuator with an upstream gearbox can be more flexible in terms of its application and operating conditions, as the gearbox can allow different ratios and torques to meet different requirements. Unlimited speed range: An actuator with a gearbox as a brake can operate effectively across unlimited speed ranges. Even if the system accelerates, it can still be stopped quickly. Reduced wear: An actuator with a gearbox as a brake may be subject to less wear because it has to withstand lower forces to stop the system. This can lead to an increased service life for the actuator. Reduced stress on the joints: Translational movements can lead to reduced stress on the joints because translational movements involve a simple combination of different movements that require little coordination and control. Simple control: Translational movements are easier to control than rotational movements because they are a simple combination of different This requires movement. This can increase accuracy and reduce errors, especially in applications where precise positioning is required.

[0009] The transmission can have a transmission input element and a transmission output element. The transmission input element can be coupled to the actuator, and the transmission output element can be coupled to the rotatable component. The transmission can be arranged in a housing, the housing of which may have a through-opening for the partial passage of the transmission input element. The transmission input element can have a shaft section for coupling to the actuator, the shaft section of which may extend at least partially through the through-opening. The transmission input element can be configured to act as a force input into the transmission and additionally or alternatively as a force output from the transmission. The transmission output element can be configured to act as a force input into the transmission and additionally or alternatively as a force output from the transmission.

[0010] The gearbox can be multi-stage. A multi-stage gearbox can offer a wide range of gear ratios. For example, a multi-stage gearbox can be at least partially coaxial and compact. Furthermore, different gearbox types can be easily combined. Alternatively, the gearbox can be single-stage.

[0011] The transmission can be designed as a gear transmission. Gear transmissions are easy to manufacture and require little maintenance.

[0012] The gearbox can incorporate a planetary gear set. Planetary gear sets can offer high torque density and be manufactured cost-effectively.

[0013] The gearbox output element and the gearbox input element can be rotatable. This allows the actuator to reliably amplify a rotary braking torque.

[0014] The transmission output element can be rotatable and the transmission input element can be movable translationally. This allows for advantageous conversion between rotary and translational motion.

[0015] The transmission output element can be a gear, and the transmission input element can be a rack. The transmission output element and input element can form a rack and pinion drive. A rack and pinion drive enables precise and reliable conversion between rotary and linear motion. Furthermore, high speeds and accelerations can be achieved.

[0016] The adjusting device can include a guide element that may be designed to guide a translational movement of the rack. In this way, the operation of the transmission can be advantageously influenced.

[0017] The magnetorheological medium can be a magnetorheological fluid or a magnetorheological liquid. It can be a heterogeneous mixture of magnetically polarizable particles, which can also be referred to as a magnetorheological liquid. Alternatively, the magnetorheological medium can be a powder. The magnetorheological medium can solidify, for example, by applying a magnetic field, i.e., by energizing a coil.

[0018] Additionally or alternatively, the magnetorheological medium can comprise a magnetorheological elastomer. This elastomer can consist of an elastomer matrix and magnetically active particles dispersed within it. The viscoelastic or dynamic-mechanical properties of these elastomers can be rapidly and reversibly altered by applying an external magnetic field. The use of magnetorheological elastomers eliminates the need for a seal, as a seal against a fluid is unnecessary. The elimination of both the seal and the fluid allows for very low no-load torque. Furthermore, a high braking torque can be generated, and sedimentation and / or segregation can be avoided. Particle wear can be prevented, the need for a filling process and / or coil sealing can be eliminated, and particle orientation can be influenced.The magnetorheological elastomer can be installed in any mounting position.

[0019] The stationary component can be designed as a housing and the rotating component as a shaft. Alternatively, the stationary component can be designed as a shaft and the rotating component as a housing.

[0020] A method for operating an embodiment of an actuating device mentioned herein comprises an energizing step and a deactivation step. In the energizing step, the coil is energized to generate the magnetic field to bring the magnetorheological medium into an activated state. In the deactivation step, the coil is deactivated to deactivate the magnetic field and bring the magnetorheological medium into a resting state.

[0021] By carrying out the method, an embodiment of an actuating device mentioned herein can be operated advantageously.

[0022] An embodiment of the proposed adjusting device is explained in more detail below with reference to the accompanying figures. These show: Fig. 1 a schematic representation of an embodiment of an actuating device; Fig. 2 a schematic representation of an embodiment of an actuating device; Fig. 3 a schematic representation of an embodiment of an actuating device; Fig. 4 a schematic representation of an embodiment of an actuating device; Fig. 5 a schematic representation of an embodiment of an actuating device; and Fig. 6 a flowchart of an exemplary embodiment of a method for operating an actuator.

[0023] Identical or similar elements are designated by identical or similar reference symbols in the following figures, with repeated descriptions being omitted for the sake of clarity.

[0024] Fig. Figure 1 shows a schematic representation, more precisely a sectional view, of an embodiment of an actuating device 100 for a vehicle. The vehicle is, for example, a motor vehicle such as a passenger car, a motorcycle, a commercial vehicle, or the like. The actuating device 100 is designed, for example, to enable a user to operate a vehicle function. For example, the actuating device 100 can be manually operated by a vehicle occupant, for example, via an actuating element. The actuating element is, for example, designed as a knob or a coupling element.

[0025] The actuator 100 comprises a stationary component 105, a rotatable component 110, a magnetorheological medium 115, a coil 120, and a gearbox 125. The rotatable component 110 is rotatably mounted relative to the stationary component 105, wherein the rotatable component 110 is, for example, mounted internally and the stationary component 105 is, for example, arranged externally. According to one embodiment, the stationary component 105 is designed as a housing and the rotatable component 110 is designed as a shaft. In other words, the housing is designed to be stationary and the shaft is designed to rotate.

[0026] The magnetorheological medium 115 is arranged in a space 130 between the stationary component 105 and the rotatable component 110. More precisely, the magnetorheological medium 115 at least partially surrounds the coil 120. In a rest state, the magnetorheological medium 115 produces a first resistance characteristic for movement of the rotatable component 110 relative to the stationary component 105. In an activated state, the magnetorheological medium 115 produces a second resistance characteristic for movement of the rotatable component 110 relative to the stationary component 105.

[0027] According to one embodiment, the magnetorheological medium 115 is at least one MRE disk (MRE = magnetorheological elastomer) fixed to the rotatable component 110. According to the embodiment shown here, the magnetorheological medium 115 comprises two MRE disks fixed axially spaced apart from each other on the movable component 110. A gap 135, which can also be referred to as the MRE gap, is thus formed between the magnetorheological medium 115 and the stationary component 105.

[0028] The magnetorheological medium 115 is designed as a magnetorheological elastomer according to the embodiment shown here. Magnetorheological elastomers generally comprise an elastomer matrix and magnetically active particles dispersed therein. The viscoelastic or dynamic-mechanical properties of these elastomers can be rapidly and reversibly changed by applying an external magnetic field.

[0029] The particles of the magnetorheological medium 115 are, for example, embedded in an elastomer matrix and are not aligned in a resting state, i.e., they are isotropic. The magnetorheological medium 115 can therefore also be described as an isotropic magnetorheological medium. In an activated state, the magnetorheological medium 115 expands in the magnetic field in the direction of the magnetic field lines and closes the magnetic circuit. Thus, the gap 135 also closes.

[0030] Alternatively, the particles of the magnetorheological medium 115 are aligned in a resting state, for example during production, i.e., anisotropic. The magnetorheological medium 115 can therefore also be described as an anisotropic magnetorheological medium. In an activated state, for example, the magnetorheological medium 115 expands in the magnetic field in the direction of the magnetic field lines and closes the magnetic circuit. Thus, the gap 135 also closes.

[0031] Magnetorheological Medium 115, for example, is a magnetorheological elastomer and contains, for instance, the following materials, which can also be combined: polyurethane (PUR), styrene-butadiene (SBR), polychlorobutadiene (CR), ethylene propylene diene terpolymer (EPDM / EPM), acrylonitrile butadiene (NBR), hydrogenated acrylonitrile butadiene (HNBR), natural rubber (NR), silicone, partially cross-linked polyolefin-based blends (EPDM / PP), thermoplastic elastomers such as TPE, TPC, TPU, TPS, TPV, etc., and other elastomers and elastomer blends / mixtures. Additionally or alternatively, Magnetorheological Medium 115 can also be a magnetorheological fluid. The particles in this fluid may contain, for example, carbonyl iron, cobalt, nickel, and / or iron particles.

[0032] The coil 120 is, for example, arranged on the stationary component 105 and is designed to generate a magnetic field. This magnetic field is designed to transfer the magnetorheological medium 115 between the rest state and the activation state. In an activated state of the actuator 100, the coil 120 is energized and generates the magnetic field. Due to the magnetic flux, the magnetorheological medium 115 expands in the direction of the stationary component 105, more precisely in the direction of the gap 135, whereupon the gap 135 closes (not shown here). This results in a high resistance characteristic for the movement of the rotatable component 110.

[0033] The gearbox 125 is coupled to the rotatable component 110 and can be coupled to the user-operated actuator. According to one embodiment, the gearbox 125 is designed as a gear drive. Additionally or alternatively, the gearbox 125 has a planetary gear drive.

[0034] The gearbox 125, for example, has a gearbox input element 140 and a gearbox output element 145. The gearbox input element 140 can be coupled to the actuating element, while the gearbox output element 145 is coupled to the rotatable component 110. The gearbox input element 140 and the gearbox output element 145 are, for example, rotatable.

[0035] According to one embodiment, the transmission 125 is arranged in a housing 150, wherein a coupling section 155 of the transmission input element 140 is at least partially passed through a through-opening 160 of the housing 150. Additionally, for example, a gear 170 and another gear 172 are arranged in the housing 150.

[0036] A braking torque is shown by way of example by means of arrow 165. For example, a user actuates the actuator that can be coupled to the transmission input element 140, whereby the braking torque is generated by the actuator 100. In this case, for example, the tooth contours of the transmission input element 140 and the tooth contours of the gear 170 mesh with each other. The gears 170 and 172 are rotationally fixed to each other and arranged coaxially, thus making the transmission 125, for example, a multi-stage design. The tooth contours of the further gear 172 and the tooth contours of the transmission output element 145 also mesh with each other. The transmission input element 140 has a larger number of teeth than the gear 170. The gear 170 has a smaller number of teeth than the further gear 172. The further gear 172 has a larger number of teeth than the transmission output element 145.

[0037] The actuator 100, for example, has a cover 175 designed to cover the housing. More precisely, the cover 175 closes the housing on a side opposite a base 180. This provides mechanical protection for the components stored inside the housing. The cover 175 is, for example, magnetically non-conductive.

[0038] The shaft protrudes partially through a through-opening of the cover 175 and at least partially into the housing 150, the section of the shaft protruding from the through-opening of the cover 175 being non-rotatably coupled to the transmission output element 145.

[0039] According to one embodiment, a circuit board 185 is arranged on the upper surface of the cover 175. According to the embodiment shown here, a bearing 190 is provided for supporting the shaft. More precisely, the bearing 190 is arranged between the cover 175 and the shaft and is designed, for illustrative purposes only, as a rolling bearing.

[0040] For example, a magnetic field barrier 195 is arranged on an inner side of the base 180; more precisely, the magnetic field barrier is arranged between the inner side of the base 180 and an underside of the shaft. A sliding bearing 198 for the shaft is also arranged on the base 180.

[0041] In other words, it shows Fig. Figure 1 shows a schematic diagram of the positioning device 100, which can also be described as a rotary actuator. Applying a magnetic field generates a torque through the magnetorheological medium 115. Software integration results in a mechatronic actuator with adaptive torques / forces.

[0042] Fig. Figure 2 shows a schematic representation of an embodiment of an actuating device 100 for a vehicle. The actuating device 100 is similar to or corresponds to the actuating device from Fig. 1, except that the stationary component 105 is designed as a shaft and the rotatable component 110 is designed as a housing. Additionally, the housing of the gearbox 125 is omitted.

[0043] The coil 120 is shown attached to the rotatable component 110 for illustrative purposes only; alternatively, the coil 120 can be attached to the stationary component 105. The magnetorheological medium 115 is shown attached to the stationary component 105 for illustrative purposes only; alternatively, the magnetorheological medium 115 can be attached to the rotatable component 110.

[0044] The transmission output element 145 is coupled to the rotatable component 110, so that the transmission output element 145 spans the stationary component 105. The gears 170, 172 are only shown as examples molded in one piece.

[0045] Fig. Figure 3 shows a schematic representation of an embodiment of an actuating device 100 for a vehicle. The actuating device 100 is similar to or corresponds to the actuating device from Fig. 1, except that the transmission output element 145 is designed as a gear and the transmission input element 140 is designed as a rack. Thus, the transmission output element 145 together with the transmission input element 140, for example, forms a rack and pinion transmission.

[0046] The gearbox 125 is shown in section, for example, with the gearbox output element 145 arranged inside and the gearbox input element 140 arranged outside.

[0047] According to one embodiment, a position sensor 300 is arranged on the circuit board 185.

[0048] By incorporating a gearbox 125, which converts rotary movements into translational movements, the conversion can be achieved using the gear in conjunction with the rack. In this way, this MRE technology and functionality can also be used for translational systems.

[0049] Fig. Figure 4 shows a schematic representation of an embodiment of an actuating device 100 for a vehicle. The actuating device 100 corresponds to the actuating device from Fig. 3, where the gearbox 125 is shown in a side view and the remaining actuating device 100 is shown in a sectional view. In other words, a partial section of the actuating device 100 is shown.

[0050] Due to the illustration, only the transmission input element 140 of the transmission 125 is visible. According to an exemplary embodiment, the transmission input element 140 is translationally movable, the translational movement being represented by a double arrow 400.

[0051] Fig. Figure 5 shows a schematic representation of an embodiment of an actuating device 100 for a vehicle. The actuating device 100 is similar to or corresponds to the actuating device from Fig. 4, wherein the actuating device 100 is shown in a top view from the gearbox 125.

[0052] The rotatable component 110 is rotatable, the rotary motion being represented by a double arrow 500. The transmission output element 145 is also rotatable, with the double arrow 500 also representing this rotary motion. The transmission input element 140 is, for example, translationally movable, with the translational motion being represented by the double arrow 400. The tooth contours of the transmission output element 145 and the tooth contours of the transmission input element 140 mesh with each other, with a tooth engagement area 505 being formed on an inner surface of the transmission input element 140 only as an example.

[0053] According to one embodiment, the actuating device 100 has a guide element 510 designed to guide the translational movement of the gear input element 140, which is designed as a rack. For this purpose, the guide element 510 is, by way of example, arranged on an outer side of the gear input element 140. In other words, the gear input element 140 is arranged between two parts of the guide element 510.

[0054] Fig. Figure 6 shows a flowchart of an embodiment of method 600 for operating an actuator. Method 600 is designed to operate the actuator from one of the figures described above or a similar actuator.

[0055] The procedure 600 comprises a step 605 of energizing and a step 610 of deactivating. In step 605, the coil is energized to generate the magnetic field to bring the magnetorheological medium into an activated state. In step 610, the coil is deactivated to deactivate the magnetic field and bring the magnetorheological medium into a resting state.

Claims

[1] Actuating device (100) for a vehicle, wherein the actuating device (100) has the following features: a fixed component (105); a rotatable component (110) mounted relative to the stationary component (105); a magnetorheological medium (115) which is arranged in an intermediate space (130) between the stationary component (105) and the rotatable component (110) and is designed to produce a first resistance characteristic for a movement of the rotatable component (110) relative to the stationary component (105) in a rest state and a second resistance characteristic for the movement of the rotatable component (110) relative to the stationary component (105) in an activation state; a coil (120) configured to generate a magnetic field, wherein the magnetic field is configured to cause the magnetorheological medium (115) to transition between the rest state and the activation state; and a gearbox (125) that is coupled to the rotatable component (110) and can be coupled to an actuating element that can be operated by a user. [2] Actuating device (100) according to claim 1, wherein the transmission (125) has a transmission input element (140) and a transmission output element (145), wherein the transmission input element (140) can be coupled to the actuating element and wherein the transmission output element (145) is coupled to the rotatable component. [3] Actuating device (100) according to one of the preceding claims, wherein the transmission (125) is designed as a multi-stage device. [4] Actuating device (100) according to one of the preceding claims, wherein the transmission (125) is designed as a gear transmission. [5] Actuating device (100) according to one of the preceding claims, wherein the transmission (125) comprises a planetary gear. [6] Actuating device (100) according to one of the preceding claims, wherein the transmission output element (145) is rotatable and wherein the transmission input element (140) is rotatable. [7] Actuating device (100) according to one of the preceding claims, wherein the transmission output element (145) is rotatable and wherein the transmission input element (140) is movable translationally. [8] Actuating device (100) according to one of the preceding claims, wherein the transmission output element (145) is designed as a gear and wherein the transmission input element (140) is designed as a rack, wherein the transmission output element (145) with the transmission input element (140) forms a rack and pinion transmission. [9] Actuating device (100) according to claim 8, comprising a guide element (510) designed to guide a translational movement of the rack. [10] Actuating device (100) according to one of the preceding claims, wherein the magnetorheological medium (115) comprises a magnetorheological fluid. [11] Actuating device (100) according to one of the preceding claims, wherein the magnetorheological medium (115) comprises a magnetorheological elastomer. [12] Actuating device (100) according to one of the preceding claims, wherein the stationary component (105) is designed as a housing and the rotatable component (110) is designed as a shaft or wherein the stationary component (105) is designed as a shaft and the rotatable component (110) is designed as a housing. [13] Method (600) for operating an actuating device (100) according to any one of claims 1 to 12, wherein the method (605) comprises the following steps: Energizing (605) the coil (120) to generate the magnetic field in order to bring the magnetorheological medium (115) into an activation state; and Deactivating (610) the coil (120) to deactivate the magnetic field in order to bring the magnetorheological medium (115) to a resting state.

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