DE102018203700B4 - Rotation angle detection device for a component of a brake of a vehicle and method for determining a rotation angle position of the component - Google Patents

Abstract

Rotation angle detection device (1) for a component of a brake of a vehicle, comprising a brakeable component which is connected to wheels of the vehicle and which is rotatable about an axis (4), at least one switching section which extends over a circumferential angle portion of the brakeable component and in the brakeable component is integrated, a sensor (6) for detecting the at least one switching section, a sensor fastening device (7) which cannot be rotated relative to the axis (4), the sensor (6) being arranged on the sensor fastening device (7). in that the at least one switching section can be detected by the sensor (6) when the brakeable component is rotated, and an evaluation unit (8) which is designed to process a signal output by the sensor (6) when the switching section is detected, the brakeable Component is a brake disc (2), the brake disc (2) has at least one recess (9) in its peripheral surface, the depth of which can be detected with the sensor (6), and a brake disc material (10) present in the at least one recess (9). ), which can be detected by the sensor (6), forms the switching section, characterized in that a plurality of recesses (9) are provided, and the recesses (9) have different depths from an outer diameter of the brake disc (2).

Description

The invention relates to a rotation angle detection device for a component of a brake of a vehicle, in particular a rotation angle detection device which enables detection of a speed of a rotatable component of a brake of a rail vehicle, and methods for determining a rotation angle position and a speed of the rotatable component.

The speed of a rail vehicle is usually recorded by a speed detection device at the end of an axle and then converted into a speed of the rail vehicle using the wheel diameter. For this purpose, each speed detection device must be individually equipped with a separate pulse wheel. Furthermore, there is a risk that the speed detection device will be easily damaged due to its position at the end of the axle.

The publication DE 199 57 632 A1 discloses a rotation angle detection device with a brakeable component with a switching section which extends over a circumferential angle portion of the brakeable component and is integrated therein. The rotation angle detection device further has a sensor for detecting the switching section that cannot be rotated relative to an axis of the brakeable component. In addition, the rotation angle detection device has an evaluation unit for evaluating a signal output by the sensor.

In print DE 88 04 239 U1 a rotation angle detection device according to the preamble of claim 1 is disclosed.

The invention is based on the object of providing a rotation angle detection device for a vehicle which does not have the above disadvantages and enables cost-effective, reliable detection of a rotation angle, and thus a rotational speed and a speed.

The object is achieved by a rotation angle detection device according to claim 1 and method according to claims 13 and 14. Further developments of the invention are the subject of the dependent claims.

The rotation angle detection device according to the invention with the features according to claim 1 makes it possible to use pulses from a switching section, which is integrated in an existing rotatable component of a brake, for a rotation angle detection of the rotatable component, and thus of the wheels. A sensor is arranged in such a way that it is actuated by a temporary presence of the switching section in the range of a switching distance of the sensor when the rotatable component is rotated, and thus detects the presence. By choosing geometric properties of the switching section and the installation position, the switching distance or, in the case of an analog sensor, by specifying a threshold value of the sensor, it is possible for the sensor to distinguish between the presence and absence of the switching section of the rotatable component. It is therefore not necessary to provide an additional speed detection device with a separate pulse wheel, which saves costs. The angle of rotation and the speed are recorded directly on the brake disc instead of being recorded by an additionally attached speed detection device, which avoids inaccuracies. By arranging the sensor in the area of the brake, it is also provided in a protected area compared to an arrangement at the end of the axle.

According to the invention, the brakeable component is a brake disc. This version has advantages over, for example, block brakes on rail vehicles in terms of less wear on wheel treads, better cooling with an associated higher braking performance, and lower noise development.

If the brake disk advantageously has recesses, for example cooling air holes, in at least one of its side surfaces, the brake disk material adjacent to the recesses can act as a switching section for the sensor, so that no additional switching elements are required. With a rotating brake disc, the sensor detects a state in which, due to one of the recesses, there is no brake disc material in the area of the switching distance of the sensor, i.e. an absence of the switching section, and a state in which the brake disc material adjacent to the recesses is in the Detection range of the sensor is located, i.e. the presence of the switching section.

In another advantageous development, in which the brake disc is alternatively or additionally provided with recesses in its peripheral surface, preferably for cooling the brake disc, the brake disc material adjacent to the recesses can act as the switching section for the sensor.

Since the brake disc according to the invention has at least one recess in its peripheral surface, for example to reduce weight or for balancing, the brake disc material provided in the recesses can act as the switching section for the sensor.

If the recess is advantageously recessed starting from an outer peripheral surface, both the brake disc material present in the recess and a brake disc material surrounding the recesses can act as the switching section for the sensor.

When providing recesses according to the invention that have different depths from an outer diameter of the brake disk, it is possible for an angular position of the brake disk to be detected via the different depths. For example, if one of the recesses has a different depth than other recesses, this makes it possible to assign an angular position of the brake disc to the position of this one recess.

Furthermore, according to the invention, several depressions have different depths, so that the angular position can be determined by assigning a pattern recognizable by the sensor to a sequence of different depths.

Advantageously, the brake disc material is formed between the depressions or recesses by webs which are integrally connected thereto between two discs, each of which forms one of the side surfaces of the brake disc. The webs can either be arranged like a pin like a dome between the disks or be rib-shaped, so that the weight of the brake disk, and thus a moving mass, can be saved. The rib-shaped webs can be arranged radially or can be curved in such a way that cooling air is transported between the panes. The brake disc material between the depressions or the recesses can then be used without providing additional switching elements to actuate the sensor and thus to carry out the rotation angle detection for the brake disc.

In an advantageous embodiment of the speed detection device, the sensor is an inductive proximity sensor. Since the brake disc is usually made of ferromagnetic metal, the switching sections can be reliably identified.

If the sensor is advantageously an optical sensor, the ferromagnetic properties of the material are not important for detecting the switching sections, so that the choice of material is more variable.

If the sensor is advantageously provided as a capacitive sensor, on the one hand there is a more variable selection of materials, but on the other hand the sensor is not sensitive to contamination or the contamination can be compensated for more easily.

In an advantageous development, the sensor is an analog sensor. This brings advantages when detecting the switching sections at low speeds and simplifies the detection of different depths of the depressions.

An alternative, advantageous provision of the sensor as a digital sensor simplifies signal processing and brings advantages in signal processing, particularly at high speeds.

Advantageously, the sensor fastening device is a brake caliper. This means that an already existing component of the brake that cannot be rotated relative to the axis can be used simply and cost-effectively as a sensor fastening device without the need for an additional component.

Since several rotation angle detection devices must be provided in a rail vehicle, it is preferably used therein in order to achieve the aforementioned advantages.

In a method according to the invention, a rotation angle position of the brakeable component can be easily detected without additional components. The signals are analyzed by the evaluation unit and the signals detected by the sensor when the brakeable component is rotated are converted into a time-dependent pattern from the detected signals, their amplitude or time interval, either via different depths of depressions or different distances between the depressions or recesses in the circumferential direction can be different. A corresponding cyclic pattern is then created from the signals. Alternatively, only one depression can have a different depth than the other depressions in order to generate the cyclic pattern. The rotation angle position of the brakeable component is then assigned to the cyclic pattern.

In a further method according to the invention, a speed of the brakeable component can be easily recorded without additional components. The signals detected by the sensor when the brakeable component is rotated are converted into either different depths of depressions or different distances between the depressions or recesses in the circumferential direction A time-dependent pattern is created from the recorded signals, whose amplitude or time interval can be different. This pattern repeats with each complete revolution of the rotatable component and is therefore cyclical. A rotation frequency can then be assigned to this cyclic pattern, from which the speed of the brake disc can be calculated.

The invention will now be explained by means of embodiments with reference to the accompanying drawings.

• 1a und 1b eine schematische Darstellung einer Drehwinkelerfassungseinrichtung mit einer Bremsscheibe mit Aussparungen in ihren Seitenflächen;
• 2a und 2b eine schematische Darstellung der Drehwinkelerfassungseinrichtung mit einer Bremsscheibe mit Aussparungen und mit Vertiefungen in ihrer Umfangsfläche;
• 3a bis 3e jeweils eine Vergrößerung eines Abschnitts des äußeren Umfangs der Bremsscheibe mit den Aussparungen und mit den Vertiefungen in ihrer Umfangsfläche; und
• 4a und 4b eine schematische Darstellung einer Bremsscheibe, in der das zwischen den Aussparungen und in Vertiefungen vorgesehene Bremsscheibenmaterial durch Gussstege gebildet ist.

Show in particular

• 1a and 1b a schematic representation of a rotation angle detection device with a brake disc with recesses in its side surfaces;
• 2a and 2 B a schematic representation of the rotation angle detection device with a brake disc with recesses and with depressions in its peripheral surface;
• 3a until 3e each an enlargement of a section of the outer circumference of the brake disc with the recesses and with the depressions in its peripheral surface; and
• 4a and 4b a schematic representation of a brake disc, in which the brake disc material provided between the recesses and in recesses is formed by cast webs.

1a and 1b show a schematic representation of a rotation angle detection device 1 with a brake disc 2. 1a shows a view in the direction of an axis 4 and 1 b a view perpendicular to the direction of the axis 4. The brake disc 2 is a brakeable component of a brake of a vehicle. The brake disc 2 is connected to the wheels of the vehicle and can be rotated about the axis 4. In particular, the vehicle can be a rail vehicle. Alternatively, the brakeable component can also be a brake drum of the vehicle or a braked wheel of the rail vehicle.

The brake disc 2 is provided with recesses 3 in its side surfaces. These recesses 3 can also be used for ventilation, i.e. for cooling, of the brake disc 2. The recesses 3 are arranged radially at the same distance from the axis 4 and the brake disc 2 has a brake disc material 5 that is radially adjacent to the recesses 3 between the recesses 3 in a circumferential angular portion of the brake disc 2. The recesses 3 go completely through the brake disc 2. Alternatively, they can also just form recesses in the brake disc 2, which do not go completely through the brake disc.

The rotation angle detection device 1 has a sensor 6. The sensor 6 is arranged so that it can detect switching sections of the rotation angle detection device 1. When one of the switching sections is detected, the sensor 6 outputs a corresponding signal. The switching sections are in the in 1 The brake disc 2 shown in each case has the brake disc material 5, which is located radially adjacent to the recesses 3, i.e. circumferentially between them, whereby the switching sections are integrated into the brake disc 2. The recesses 3 are not detected by the sensor 6 as switching sections. Brake disc material, which may be located in an axial extension of one of the recesses 3 in another section of the brake disc 2, is also not detected by the sensor 6. Alternatively, a recess 3 can also be defined as the switching section.

The rotation angle detection device 1 is provided with a sensor fastening device 7, with the help of which the sensor 6 is fastened so that it cannot be rotated relative to the axis 4.

The rotation angle detection device 1 also has an evaluation unit 8, which processes and evaluates the signal output by the sensor 6.

2a and 2 B each show a schematic representation of a rotation angle detection device 1 of an alternative embodiment with a different brake disc 2. 2a shows a view in the direction of axis 4 and 2 B a view perpendicular to the direction of axis 4.

Here too, the brake disc 2 is the braking component of the vehicle's brakes. The brake disc 2 is connected to the wheels of the vehicle and can be rotated about the axis 4.

In contrast to the brake disc 2 in 1 a and 1 b Here, the brake disc 2 has the recesses 3 and additional depressions 9 in its peripheral surface. Alternatively, the brake disc 2 can also have recesses 3 and depressions 9 both in the side surfaces and in the peripheral surface.

The recesses 3 are defined so that they are recesses in brake disc material, i.e. areas in which there is no brake disc material that can be detected by the sensor 6. The recesses 3 are either continuous through the brake disc 2 or have a depth from the brake disc surface, so that brake disc material in the bottom of the recess cannot be detected by the sensor 6.

The depressions 9 are defined in such a way that the brake disk material in the bottom of the recess can be detected by the sensor 6, and the brake disk material in the bottom of the depressions 9 thus also forms the switching sections. The depressions 9 are recessed with different predetermined depths compared to the outer diameter of the brake disc 2. The recesses 9 thus differ from the recesses 3, in which no brake disc material in the recesses 3 can be detected by the sensor 6.

The sensor 6 and the evaluation unit 8 are designed so that different predetermined depths of the depressions 9 are detected or processed. The sensor 6 is designed as an inductive sensor and works on an analog principle. Alternatively, optical or capacitive sensors can also be used, which also work on an analog principle. Digital sensors can also be used as a further alternative.

The rotation angle detection device 1 is in 2a and 2 B provided with a sensor fastening device 7, which is designed as a brake caliper with brake pads 11, and with the help of which the sensor 6 is also fastened here so that it cannot be rotated relative to the axis 4.

The rotation angle detection device 1 also has an evaluation unit 8 here, which processes and evaluates the signal output by the sensor 6.

In 3a until 3e Different arrangements of the recesses 3 arranged in the peripheral surface of the brake disc 2 and different arrangements and properties of the depressions 9 arranged in the peripheral surface of the brake disc 2 are shown and will be explained below.

The brake disc 2 in 3a has only one recess 3, which extends inwards from the peripheral surface on the outer diameter of the brake disc 2, with the brake disc material 5 adjacent to the recess 3 serving as the switching section.

In 3b Two recesses 3 are provided in the brake disc 2, with the brake disc material 5 adjacent to the recesses 3, including the brake disc material 5 between the recesses 3, serving as the switching section.

The arrangement in 3c is provided with a recess 9 in the brake disc 2. Here, both the brake disc material 5 adjacent to the recess 9 and the brake disc material 10 in the recess 9 serve as one of the switching sections. When using a type of sensor 6 that detects different distances from switching sections, the different distances from the brake disk material 5 between the recesses 3 and from the brake disk material 10 in the recess 9 can be detected, whereby different signals are output, which are then for the Rotation angle detection can be used.

The arrangement in 3d has two recesses 9 in the brake disc 2. The depressions 9 have different depths from the outer brake disc diameter. Here too, the switching sections are both the brake disc material 5 adjacent to the recesses 9 and the brake disc material 10 in the recess 9.

In 3e the arrangement is shown with adjacent recesses 9, which have different depths from the outer brake disc diameter, and with one of the recesses 3. Thus, both the brake disc material 5 adjacent to the recesses 9 and the recess 3 and the brake disc material 10 in the recesses 9 each form one of the switching sections.

4a and 4b show a half-section of a schematic representation of another brake disc 2, in which the brake disc material 5, 10 provided between the recesses 3 and in the recesses 9 is formed by webs. 4a shows a view in the direction of axis 4 and 4b a view perpendicular to the direction of the axis 4. The webs, which form the brake disc material 5 between the recesses 3 and the brake disc material 10 in the recesses 9, are cast together with adjacent discs, each of which forms one of the braking surfaces of the brake disc 2, in a casting process manufactured integrally. The webs are designed either as ribs 12 or as domes 13. Alternatively, other manufacturing processes are also possible.

During operation, when the vehicle is driving, i.e. when the brake disc 2 is rotated, the brake disc material 5, 10 adjacent to the recess 3 or the recess 9 is detected by the sensor 6 as the switching section. In addition, different depths of the depressions 9 are also recorded. The sensor 6 then gives a signal that corresponds to a presence and, if necessary, a tie field information of the switching section corresponds. Alternatively, only the recesses 3 are recorded.

The evaluation unit 8 analyzes the signals and determines a cyclic pattern from the signals while the brake disc 2 is rotated. Several switching sections are provided to record the cyclic pattern. Alternatively, either only one switching section can be provided, or the switching sections must be designed such that at least one switching section differs from other switching sections in terms of its depth or distance.

The cyclic pattern, for example the individual signal when there is only one switching section, or the pattern in which at least one of the signals differs from the remaining signals due to the at least one different switching section, is then assigned to a complete revolution.

The speed of the brake disc 2 is then determined from a repetition frequency of the individual signal or the pattern of signals, i.e. a rotation frequency of complete revolutions of the brake disc. The speed of the vehicle can then be determined from the speed of the brake disc 2.

In addition or as an alternative to determining the speed of the brake disc 2, an angle of rotation position of the brake disc can also be determined. Here too, the evaluation unit 8 analyzes the signals and determines a cyclic pattern from the signals while the brake disc 2 is rotated. For the detection of the cyclic pattern, either only one switching section may be provided here, or the switching sections must be designed in such a way that at least one switching section differs from other switching sections. The cyclic pattern, for example the individual signal when there is only one switching section, or the pattern in which at least one of the signals differs from the remaining signals due to the at least one different switching section, is then assigned to a complete revolution.

The cyclic pattern is assigned to a rotation angle position of the brake disc 2, so that predetermined features of the cyclic pattern correspond to predetermined locations, that is to say predetermined angle information. According to a desired accuracy of the rotation angle position, only the signals from the sensors are evaluated by the switching sections or, if greater accuracy is desired, these signals are interpolated.

All features presented in the description, the following claims and the drawing can be essential to the invention both individually and in any combination with one another.

REFERENCE SYMBOL LIST

1

Rotation angle detection device

2

Brake disc

3

recess

4

axis

5

adjacent brake disc material

6

sensor

7

Sensor mounting device

8th

Evaluation unit

9

deepening

10

Brake disc material in recess

11

brake pad

12

rib

13

Cathedral

Claims (14)

Rotation angle detection device (1) for a component of a brake of a vehicle, comprising a brakeable component which is connected to wheels of the vehicle and which is rotatable about an axis (4), at least one switching section which extends over a circumferential angle portion of the brakeable component and is integrated into the brakeable component, a sensor (6) for detecting the at least one switching section, a sensor fastening device (7) which cannot be rotated relative to the axis (4), the sensor (6) being arranged on the sensor fastening device (7). is that the at least one switching section can be detected by the sensor (6) when the brakeable component is rotated, and an evaluation unit (8) which is designed to process a signal output by the sensor (6) when the switching section is detected, wherein the brakeable component is a brake disc (2), the brake disc (2) has at least one recess (9) in its peripheral surface, the depth of which can be detected by the sensor (6), and one in the at least one recess (9). Brake disc material (10), which can be detected by the sensor (6), forms the switching section, characterized in that a plurality of recesses (9) are provided, and the Depressions (9), starting from an outer diameter of the brake disc (2), have different depths. Rotation angle detection device (1) according to Claim 1 , wherein the brake disc (2) has at least one recess (3) in at least one of its side surfaces, and a brake disc material (5) which is radially adjacent to the at least one recess (3) and which can be detected by the sensor (6) forms the switching section . Rotation angle detection device (1) according to Claim 1 or 2 , wherein the brake disk (2) has at least one recess (3) in its peripheral surface, and a brake disk material (5) adjacent to the at least one recess (3), which can be detected by the sensor (6), forms the switching section. Rotation angle detection device (1) according to one of the preceding claims, wherein a brake disc material (5) adjacent to the at least one recess (9) and the brake disc material (10) present in the at least one recess (9), which can be detected by the sensor, each have one of the switching sections. Rotation angle detection device (1) according to one of the preceding claims, wherein the brake disc material (5) and/or the brake disc material (10) adjacent to the at least one recess (9) or recess (3), the plurality of recesses (9) or recesses (3) in the at least one recess (9) or the several recesses (9) are formed by webs between two disks, each of which forms one of the side surfaces of the brake disk (2). Rotation angle detection device (1) according to one of the preceding claims, wherein the sensor (6) is an inductive proximity switch. Rotation angle detection device (1) according to one of Claims 1 until 5 , whereby the sensor (6) is an optical sensor. Rotation angle detection device (1) according to one of Claims 1 until 5 , whereby the sensor (6) is a capacitive sensor. Rotation angle detection device (1) according to one of Claims 6 until 8th , whereby the sensor (6) is an analog sensor. Rotation angle detection device (1) according to one of Claims 6 until 8th , whereby the sensor (6) is a digital sensor. Rotation angle detection device (1) according to one of the preceding claims, wherein the sensor fastening device (7) is a brake caliper. Rail vehicle with a rotation angle detection device (1) according to one of the preceding claims. Method for determining a rotation angle position of a brakeable component with a rotation angle detection device (1) according to one of Claims 1 until 11 with the steps: detecting the signals using the sensor (6); Analyzing the signals using the evaluation unit (8); determining a cyclic pattern from the signals as the brakeable component rotates; and associating the cyclic pattern with the rotational angular position of the brakeable component. Method for determining a speed of a brakeable component with a rotation angle detection device (1) according to one of Claims 1 until 11 with the steps: detecting the signals using the sensor (6); Analyzing the signals using the evaluation unit (8); determining a cyclic pattern from the signals as the brakeable component rotates; associating the cyclic pattern with a complete revolution of the brakeable component; Determining a rotation frequency from a rotation time of the complete revolution; and determining the speed from the rotation frequency of complete revolutions.

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