Device and method for setting an actuator and braking a vehicle

Abstract

Method and device (102) for adjusting an actuator (100), wherein the device (102) comprises a lifting magnet (104), a spring (106), and a plunger (108) for moving the actuator (100), wherein the lifting magnet (104) is designed to move the plunger (108) with a magnetic force against a restoring force of the spring (106) in a working range, wherein the spring (106) has a restoring force configuration such that the spring effects negative total force gradients of the total force resulting from the restoring force and the magnetic force with respect to the stroke of the plunger (108) in the working range. Device for braking a vehicle comprising the device for adjusting the actuator. Method for braking the vehicle.

Description

State of the art

[0001] The invention relates to a device and a method for setting an actuator and for braking a vehicle.

[0002] Actuators are required in many products. For example, an actuator is used to lock a locking device, such as a latch, in an automatic parking brake (APB) or in an electromechanical brake (EMB).

[0003] A switching actuator is an example of an actuator with a simple control system. For example, a current-operated switching actuator switches depending on whether the power is on or off.

[0004] Switching creates a load on the actuator and a noise, e.g. when the actuator reaches its end stop, because the entire actuator stroke is traversed in a highly accelerated movement and the impact energy is therefore high. Disclosure of the invention

[0005] The devices and methods according to the independent claims avoid load on the actuator and noise.

[0006] A device for positioning an actuator comprises a lifting magnet, a spring and a plunger for moving the actuator, wherein the lifting magnet is designed to move the plunger with a magnetic force against a restoring force of the spring in a working range, wherein the spring has a design of the restoring force such that the spring causes negative total force gradients of the total force resulting from the restoring force and the magnetic force with respect to the stroke of the plunger in the working range.

[0007] For this purpose, the spring preferably has a spring stiffness between 5 N / mm and 10 N / mm, for example. This achieves a spring force characteristic curve, for example, with corresponding magnetic forces that is sufficiently steep for application in an APB. For pure switching actuators, the spring stiffness is typically selected to be low in order to minimize tolerance influences on the force.

[0008] The device is preferably designed for use with the adjustable actuator in current mode, with the ability to set intermediate current levels between zero and a maximum current, e.g., to run through current ramps. This allows the actuator's suitability for control mode to be utilized.

[0009] The device can be configured to control the solenoid to generate a magnetic force that increases, at least in sections, as the plunger moves against the restoring force of the spring as the stroke decreases. This prevents the actuator from striking hard with high kinetic energy at one end of the working range with minimal stroke.

[0010] The device can be configured to control the solenoid to generate a magnetic force that increases, at least in sections, with increasing stroke during movement of the plunger with the restoring force of the spring. This prevents the actuator from striking hard with high kinetic energy at one end of the working range with maximum stroke.

[0011] A device for braking a vehicle comprises a brake and an actuator, wherein the actuator is designed to fix the brake in a position of the brake in which the brake brakes the vehicle, and wherein the device for braking comprises the device for setting the actuator.

[0012] A method for positioning an actuator provides that a device comprises a lifting magnet, a spring and a plunger for moving the actuator, wherein the lifting magnet is designed to move the plunger with a magnetic force against a restoring force of the spring in a working range, wherein the spring has such a design of the restoring force that the spring causes negative total force gradients of the total force resulting from the restoring force and the magnetic force with respect to the stroke of the plunger in the working range, and wherein the lifting magnet is controlled to position the actuator.

[0013] The spring preferably has a spring stiffness between 5 N / mm and 10 N / mm.

[0014] The method may provide that the actuator is operated in a current mode with the possibility of also setting intermediate current levels between zero and maximum current, e.g. also of passing through current ramps.

[0015] It can be provided that the lifting magnet is controlled to generate a magnetic force which increases at least in sections with decreasing stroke when the plunger moves against the restoring force of the spring.

[0016] It can be provided that the lifting magnet is controlled to generate a magnetic force which, when the plunger moves with the restoring force of the spring, increases at least in sections with increasing stroke.

[0017] A method for braking a vehicle provides that a device comprises a brake and an actuator, wherein the actuator is designed to fix the brake in a position of the brake in which the brake brakes the vehicle, and wherein the device for braking comprises the device for adjusting the actuator, wherein the device for adjusting the actuator is controlled by the method for adjusting the actuator.

[0018] Further advantageous embodiments can be found in the following description and the drawing. The drawing shows: Fig. 1 a schematic representation of an actuator and a device for positioning the actuator, Fig. 2 is a schematic representation of a vehicle with a device for braking the vehicle, which device comprises the actuator and the device, Fig. 3 a spring characteristic curve, Fig. 4 a flowchart with steps of a method for setting the actuator, Fig. 5 a current curve and a curve of a movement of the actuator with decreasing stroke, Fig. 6 a current curve and a curve of a movement of the actuator with increasing stroke.

[0019] Fig. 1 schematically illustrates an actuator 100 and a device 102 for positioning the actuator 100.

[0020] The actuator 100 includes, for example, a latch for locking an APB or EMB.

[0021] The device 102 comprises a lifting magnet 104, a spring 106 and a plunger 108 for moving the actuator 100.

[0022] The lifting magnet 102 is designed to move the plunger 108 with a magnetic force M against a restoring force R of the spring 106 in a working area 108A. The plunger 108 is moved in the working area A with a stroke H.

[0023] The device 102 is designed to move the plunger 108 depending on a current through the lifting magnet 104.

[0024] In the example, the device 102 is designed to move the plunger 108 without current through the lifting magnet 104 with the restoring force R of the spring 106 to one end of the working range A with maximum stroke H. In Fig. 1, the plunger is shown at maximum stroke H. In the example, the device 102 is designed to move the plunger 108 to the other end of the working range A with minimum stroke H by applying current through the lifting magnet 104 against the restoring force R of the spring 106.

[0025] The spring 106 has a restoring force R. A spring 106 has, for example, such a design of the restoring force R that the spring causes negative total force gradients dF / dH < 0 of the total force F = R + M resulting from the restoring force R and the magnetic force with respect to the stroke H of the plunger 108 in the working range A.

[0026] The spring 108, for example, has a spring stiffness between 5 N / mm and 10 N / mm.

[0027] The device 102 is designed to operate the actuator 100 in a current mode with the possibility of also setting intermediate current levels between zero and maximum current, e.g. also to run through current ramps.

[0028] The device 102 is designed to control the lifting magnet 104 to generate a magnetic force M which, when the plunger 108 moves against the restoring force of the spring 106, increases at least in sections with decreasing stroke dH / dt < 0.

[0029] The device 102 is designed to control the lifting magnet 104 to generate a magnetic force M which, when the plunger 108 moves with the restoring force R of the spring 106, increases at least in sections with increasing stroke dH / dt > 0.

[0030] In Fig. 2, a device 110 for braking a vehicle 112 is shown schematically.

[0031] The device 110 includes a brake 114 and the actuator 100.

[0032] The actuator 100 is configured to fix the brake 114 in a position of the brake 114 in which the brake 114 brakes the vehicle 112.

[0033] The braking device 110 includes the device 102 for positioning the actuator 100.

[0034] In Fig. 3 shows the restoring force 302, the magnetic force 304 and a disturbance force 306 in Newton between 0 N and 16 N over the stroke in millimeters between 0 mm and 2 mm.

[0035] The restoring force 302 lies in the working range 108A between the magnetic force 304 and the disturbing force 306.

[0036] The restoring force 302 has a gradient whose steepness is set such that the restoring force 302 causes a negative total force gradient of the total force resulting from the restoring force 302 and the magnetic force 304 with respect to the stroke H in the working range 108A.

[0037] In Fig. 4 shows a flowchart with steps of a method for setting the actuator 100, in particular for braking the vehicle 112.

[0038] In a step 402, a current profile for controlling the lifting magnet 104 is provided.

[0039] The current profile is provided in the example for the spring 106 with the spring stiffness between 5 N / mm and 10 N / mm.

[0040] The actuator 100 is operated, for example, in a current mode with the possibility of setting intermediate current levels between zero and maximum current, e.g. also of passing through current ramps.

[0041] In the example, a first current profile is provided which provides that the lifting magnet 104 is controlled to generate a magnetic force which increases at least in sections with decreasing stroke when the plunger 108 moves against the restoring force of the spring 106.

[0042] In the example, a first current profile is provided which provides that the lifting magnet 104 is controlled 404 to generate a magnetic force which, when the plunger 108 moves with the restoring force of the spring 106, increases at least in sections with increasing stroke.

[0043] The current in the first and second current curves ranges from a minimum of 0 amperes to a maximum of 3500 milliamperes. Examples of maximum values ​​are 1500 milliamperes, 2000 milliamperes, 2500 milliamperes, and 3000 milliamperes.

[0044] In a step 404, the lifting magnet 104 is controlled to position the actuator 100.

[0045] In the example, the lifting magnet 104 is controlled with the first current profile to lock the brake 114 of the vehicle 112.

[0046] When locking the brake 114, the actuator 100 is moved to fix the brake 114 into a position in which the actuator 100 prevents movement of the brake 114.

[0047] In the example, the lifting magnet 104 is controlled with the second current profile to unlock the brake 114 of the vehicle 112.

[0048] When the brake 114 is unlocked, the actuator 100 is moved to release the brake 114 from the position in which the actuator 100 prevents movement of the brake 114.

[0049] In Fig. 5 shows a curve 502 of the first current profile and a curve 504 of the movement of the actuator 100 over time.

[0050] The curve 502 of the first current profile represents the current in amperes. The curve 504 of the movement of the actuator 100 represents the stroke in millimeters.

[0051] According to the first current profile, the current initially increases abruptly from the minimum value in the example and then ramps up to the maximum value. The maximum value is then maintained until the current abruptly drops to the minimum value in the example.

[0052] In the example, the movement profile 504 of actuator 100 begins at the minimum stroke and follows the shape of the first current profile 502 until the maximum stroke is reached. The stroke then remains at the maximum value.

[0053] In Fig. 6 shows a curve 602 of the second current profile and a curve 604 of the movement of the actuator 100 over time.

[0054] The curve 602 of the second current profile represents the current in amperes. The curve 604 of the movement of the actuator 100 represents the stroke in millimeters.

[0055] According to the second current profile, the current initially increases abruptly from the minimum value in the example and then ramps up to the maximum value. The maximum value is then maintained until the current abruptly drops to the minimum value in the example.

[0056] In the example, the movement profile 604 of the actuator 100 begins at the maximum stroke, then initially decreases in a ramp-like manner and finally abruptly until the minimum stroke is reached. The stroke then remains at the minimum stroke.

Claims

[1] Device (102) for positioning an actuator (100), characterized by , that the device (102) comprises a solenoid (104), a spring (106) and a plunger (108) for moving the actuator (100), wherein the solenoid (104) is configured to move the plunger (108) with a magnetic force against a restoring force of the spring (106) in a working range, wherein the spring (106) has such a restoring force configuration that the spring causes negative overall force gradients of the total force resulting from the restoring force and the magnetic force with respect to the stroke of the plunger (108) in the working range. [2] Device (102) according to claim 1, characterized by , that the spring (108) has a spring stiffness that is between 5 N / mm and 10 N / mm. [3] Device (102) according to any of the preceding claims, characterized by, that the device (102) is designed for current operation with the possibility of setting intermediate current levels between zero and maximum current, e.g. also to traverse current ramps. [4] Device (102) according to any of the preceding claims, characterized by , that the device (102) is designed to control the lifting magnet (104) to generate a magnetic force which, when the plunger (108) moves against the restoring force of the spring (106), increases at least section by section with decreasing stroke. [5] Device (102) according to any of the preceding claims, characterized by , that the device (102) is designed to control the lifting magnet (104) to generate a magnetic force which, when the plunger (108) is moved with the restoring force of the spring (106), increases at least section by section with increasing stroke. [6] Device (110) for braking a vehicle (112), characterized by, that the device (110) comprises a brake (114) and an actuator (100), wherein the actuator (100) is configured to fix the brake (114) in a position of the brake (114) in which the brake (114) brakes the vehicle (112), and wherein the braking device (110) comprises the device (102) for positioning the actuator (100) according to any one of claims 1 to 5. [7] Method for positioning an actuator (100), characterized by, that a device (102) comprises a solenoid (104), a spring (106) and a plunger (108) for moving the actuator (100), wherein the solenoid (104) is configured to move the plunger (108) with a magnetic force against a restoring force of the spring (106) in a working range, wherein the spring (106) has such a restoring force configuration that the spring causes negative overall force gradients of the total force resulting from the restoring force and the magnetic force with respect to the stroke of the plunger (108) in the working range, and wherein the solenoid (104) is actuated to position the actuator (100) (404). [8] Method according to claim 7, characterized by , that the spring (106) has a spring stiffness that is between 5 N / mm and 10 N / mm. [9] Method according to claim 7 or 8, characterized by, that the actuator (100) is operated in a current mode with the possibility of setting intermediate current levels between zero and maximum current, e.g. also to traverse current ramps. [10] Method according to any one of claims 7 to 9, characterized by , that the lifting magnet (104) is controlled to generate a magnetic force (404) which, when the plunger (108) moves against the restoring force of the spring (106), increases at least section by section with decreasing stroke. [11] Method according to any one of claims 7 to 9, characterized by , that the lifting magnet (104) is controlled to generate a magnetic force (404) which, when the plunger (108) moves with the restoring force of the spring (106), increases at least section by section with increasing stroke. [12] Method for braking a vehicle (112), characterized by, that a device (114) comprises a brake (114) and an actuator (100), wherein the actuator (100) is configured to fix the brake (114) in a position of the brake (114) in which the brake (114) brakes the vehicle (112), and wherein the braking device (110) comprises the device (102) for positioning the actuator (100) according to any one of claims 1 to 4, wherein the device (102) for positioning the actuator (100) is controlled by the method according to any one of claims 7 to 11 (404).

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