Operating brake cylinder with brake state detection and method for detecting the brake state of an operating brake cylinder

Description

[0001] The invention relates to a service brake cylinder, in particular a block brake, with brake condition detection, in particular for a rail vehicle, according to the preamble of claim 1. The invention also relates to a method for detecting a brake condition of a service brake cylinder, in particular a block brake.

[0002] A block brake, also called a tread brake, is very frequently used as a friction brake in rail vehicles in freight vehicles because it is simple in design and the brake blocks with their friction lining use the wheel tread of the wheel to be braked as a friction surface.

[0003] With such a tread brake, the brake pads and wheels wear out during daily operation. The condition of the brake, i.e., the brake pads, must be checked regularly for safety reasons. The current inspection procedure is regular visual inspection and testing with a tool, such as a hammer, by maintenance personnel while the brake pads are in and out. This is costly and requires highly trained maintenance personnel.

[0004] Various solutions have been proposed to check whether the brake is actually released while the train is moving after it has been released and whether it is still in the applied state after it has been applied.

[0005] Document WO 2015 / 135074 A1 describes a brake setting monitoring device for an air brake system, which comprises a non-contact proximity sensor mounted on a wall of a brake chamber to generate a signal when the back plate of the push rod comes within the detection distance of the proximity sensor. It is considered disadvantageous that the proximity sensor protrudes into the brake chamber through an opening in the housing of the brake chamber with one part, and another part, which has an electrical connection with a cable, protrudes out into the environment and is exposed to the ambient conditions.

[0006] Similar embodiments are described in the following documents: DE102015219058A; DE19857092B4; EP1384638B1; EP1640233B1; US4583071A; US5816778A; US6352137B1; US6501375B1; US7624849B2; US8616342B2; US8662602B2 WO2015135074A1; WO2016040430A1.

[0007] Therefore, the object of the invention is to provide a generic service brake cylinder, in particular a block brake, with improved brake condition detection while simultaneously reducing costs and components.

[0008] The object is achieved by a service brake cylinder having the features of claim 1 and a method having the features of claim 6.

[0009] A service brake cylinder according to the invention, in particular a block brake, comprises a housing with a spindle and a brake condition detection device for detecting an applied state and a released state of the service brake cylinder. The brake condition detection device is arranged completely within an interior space of the service brake cylinder, enclosed by the housing, and detects the position of the spindle. The brake condition detection device provides information about the piston position. Such a brake condition detection device is advantageous not only because it increases the level of safety compared to the currently established manual check, but also because it offers a simple design.

[0010] A particular advantage is that the brake condition detection device is completely enclosed within the housing of the service brake cylinder, providing excellent protection from the elements and damage. The brake condition detection device is accessible from the outside for maintenance, e.g., through a resealable maintenance opening.A method according to the invention for detecting a braking state of the above-specified service brake cylinder comprises the method steps (V1) providing a braking state detection device and arranging the braking state detection device within the service brake cylinder and supplying at least one sensor of the braking state detection device with electrical energy; (V2) generating at least one electrical signal as a braking state signal as a function of a braking state, namely the application state and / or the release state, by the sensor; and (V3) outputting a detected braking state as the application state or the release state of the service brake cylinder based on the braking state signals thus detected.

[0011] It is advantageous that the detected states, i.e., the applied and released states, can be easily and objectively processed using the brake state detection device. Additionally, the operator can use the data to monitor the release or brake application state of the brake.

[0012] A particular advantage is that this collected data is essential in tunnels (e.g., subways or long train tunnels) or in automatic / autonomous operation to prevent incorrect brake application, which can lead to unexpected smoke in poorly ventilated areas. Furthermore, potential fire sources can be detected and prevented early enough.

[0013] Advantageous further developments of the invention are specified by the subject matter of the subclaims.

[0014] According to the invention, the brake condition detection device detects the position of a pressure ring or a spindle housing connected to the spindle. Thus, existing functional components or sections thereof can advantageously be used directly or indirectly to detect the position of the spindle and thus the condition of the service brake cylinder.

[0015] According to the invention, the brake condition detection device comprises at least one sensor arranged in an interior section of the housing of the service brake cylinder between a front wall and a projection of the spindle housing. Advantageously, no other interfering components, such as springs that change their position and / or shape, are present in this area, which could lead to errors when detecting the position of the spindle.

[0016] In a further embodiment, the at least one sensor is attached to a mount by means of a mounting section, wherein an axial position of the at least one sensor on the mount is adjustable. This is advantageous because, on the one hand, the mount ensures simple arrangement and attachment, and, on the other hand, the position of the sensor can be easily adjusted in conjunction with the part whose position is to be detected.

[0017] The mount can also be designed to accommodate more than one sensor. This is advantageous if an additional sensor is used for plausibility checks.

[0018] In yet another embodiment, the at least one sensor interacts with the projection of the spindle housing in such a way that the at least one sensor is activated in the applied state (A) of the service brake cylinder depending on the position of the projection of the spindle housing and is not activated in the released state (L) of the service brake cylinder. This results in a simple design with a low number of parts.

[0019] One embodiment provides for the at least one sensor to be designed as an inductive proximity sensor or proximity switch. Such components are available on the market in suitable designs at low cost and in high quality.

[0020] Alternatively or as an additional sensor, the at least one sensor can be a contact and / or contactless sensor.

[0021] In the method according to the invention, in method step (V2), the at least one brake state signal generated by the at least one sensor is checked for plausibility using at least one further brake state signal generated by at least one further sensor. This further sensor can, for example, be mounted on the same bracket. However, it is also possible for the further sensor to be arranged at a different location in the housing of the service brake cylinder and to detect the release state, with the first sensor detecting the application state.

[0022] A further embodiment of the method according to the invention provides that the braking states (A, L) output as the applied state (A) or released state (L) of the service brake cylinder in method step (V3) are checked with signals for applying and / or releasing the service brake cylinder from a higher-level brake control system, and an alarm is output if, after receiving a signal to apply the service brake cylinder, no applied state (A) is detected, and / or if, after receiving a signal to release the service brake cylinder, no released state (L) is detected. This is advantageous because it enables simple and effective detection of non-released brake blocks in the released state and of non-applied brake blocks in the applied state.

[0023] An embodiment of the invention is described below with reference to the accompanying drawings.

[0024] They show: Figure 1 shows a schematic sectional view of an embodiment of a service brake cylinder according to the invention with a brake state detection device; and Figures 2-3 show schematic flow diagrams of inventive methods for detecting a brake state of a service brake cylinder according to Figure 1 .

[0025] Figure 1 shows a schematic sectional view of a service brake cylinder 1 according to the invention with a brake condition detection device 10.

[0026] In this example, the service brake cylinder 1 is designed as a service brake cylinder 1 of a so-called block brake, also known as a tread brake. In another embodiment, the braking device 1 is a disc brake, which is not shown here but is conceivable.

[0027] The service brake cylinder 1 comprises a housing 2, a spindle 5, a thrust ring 7 and a spindle housing 8. The generally known structure, the function of the service brake cylinder 4 and the interaction with brake linkage, brake calipers and / or brake pads are not described in further detail here.

[0028] The housing 2 of the service brake cylinder 1 has a rear wall 2a and a front wall 2b opposite the rear wall. A circumferential housing wall 2c connects the closed rear wall 2a and the front wall 2b. An interior space 3 of the housing 2 is defined by the rear wall 2a, the front wall 2b, and the housing wall 2c.

[0029] In the interior space 3 of the housing 2 of the service brake cylinder 1, the spindle 5 is arranged between the rear wall 2a and the front wall 2b, displaceably arranged in a direction of movement x, which runs along the spindle 5. The spindle 5 is connected to a service brake piston (not shown), with a brake shoe 6 attached to an end of the spindle 5 protruding through the front wall 2b. The brake shoe 6 is connected to a brake pad / brake block (not shown). The brake pad interacts with a wheel to be braked during braking operations (also not shown but easily imagined).

[0030] In a central section of the spindle 5, the thrust ring 7 and the spindle housing 8 are arranged around the spindle 5 and coupled to it in a manner not described in detail. The spindle housing 8 has a radial projection 9 in the form of a flange section. This projection 9 defines a portion of the interior space 3 between itself, the front wall 2b, the housing wall 2c, and an outer side of the spindle housing 8.

[0031] The brake, i.e. the service brake cylinder 1, has two basic states, namely the applied state A and the released state L.

[0032] In the solution state L, which is Fig. 1 As shown, a specific distance between the wheel to be braked and the brake pad / brake lining is maintained by the position of spindle 5. The spindle 5 is retracted into the housing 2.

[0033] When the brake is applied or clamped, the spindle 5 in the service brake cylinder 1 moves together with the thrust ring 7 and the spindle housing 8 towards the spindle 5 in the positive direction of movement x, and thus the brake block / brake lining is pressed onto the wheel to be braked for a braking operation. In the process, a distance between the projection 9 of the spindle housing 8 and the rear wall 2a of the housing 2 of the service brake cylinder 2 is increased. At the same time, a distance between the projection 9 of the spindle housing 8 and the front wall 2a of the housing 2 is reduced. At the end of this application or clamping movement, the brake or the service brake cylinder 1 assumes the application state A. In this case, the spindle 5, with its end connected to the brake block shoe 6, is extended out of the housing 2 by a certain amount.

[0034] When the brake is released, the movement is reversed in the negative direction x. The spindle housing 8 approaches the rear wall 2a of the housing 2. After release, the brake or service brake cylinder 1 is in the release state L.

[0035] These two states of the brake or the service brake cylinder 1, namely the release state L and the application state A, can be detected with the brake state detection device 10.

[0036] The arrangement of the brake state detection device 10 is selected such that the brake state detection device 10 can interact with a component movable in the direction of the spindle 5 in order to detect either the release state L, the application state A or both states.

[0037] In the embodiment shown, a suitable component for monitoring the two states (release state L and application state A) is the pressure ring 7 and / or the spindle housing 8, since these components are moved along with the movement of the spindle 5 when the brake is applied and released.

[0038] The brake condition detection device 10 here comprises a sensor 11 within the housing 2 of the service brake cylinder 2 in the interior 3.

[0039] The brake condition detection device 10 is arranged here in the interior space 3 of the housing 2 within the housing 2 of the service brake cylinder 1. The sensor 11 is attached to a bracket 15 between the front wall 2b and the projection 9 of the spindle housing 8 in the interior space 3.

[0040] Alternatively, the sensor 11 or an additional sensor 11 can be arranged in another section in the interior space 3 within the housing 2 between the rear wall 2a and the projection 9 of the spindle housing 8.

[0041] In this embodiment, the sensor 11 is designed as an inductive proximity sensor or inductive proximity switch, which interacts with the metallic projection 9 of the spindle housing 8 in such a way that the sensor 11 is activated in the application state A depending on the position of the projection 9 of the spindle housing 8 and is not activated in the release state L.

[0042] The sensor has a sensing side 12, a connection section 13, and a mounting section 14. When installed, the sensing side 12 faces the projection 9 of the spindle housing 8. The connection section 13 serves for the electrical connection of the sensor 11 and has an appropriate IP protection class against the ingress of moisture and dirt, e.g., with a pre-sealed / injected cable.

[0043] When the brake is applied or tightened, the spindle housing 8 with the projection 9 moves in the positive direction of movement +X toward the detection side 12 of the sensor 11. When the application state A is assumed, a sensor-specific distance value of the projection 9 (in the direction of the spindle 5) to the detection side 12 of the sensor 11 is undershot, and the sensor 11 is activated. This sensor-specific distance value or active range of the sensor 11 can be predetermined, e.g., on the sensor 11 and / or by means of a control unit 17.

[0044] When the brake is released, the sensor 11 is deactivated as soon as the sensor-specific distance value between the projection 9 and the detection side 12 of the sensor 11 is exceeded, ie when the projection 9 leaves the active range of the sensor 11.

[0045] The fastening section 14 of the sensor 11 enables a position adjustment of the sensor 11 in a specific area in the holder 15, e.g. in an axial area parallel to spindle 5. This allows the active area of ​​the sensor 11 to be adapted to the position of the projection 9.

[0046] In this way, it is possible to accurately detect the application state A by the activated sensor 11. If the sensor 11 is then deactivated and remains deactivated, the release state L can be assumed. However, the release state L can only be assumed, since no plausibility check is available.

[0047] Such a plausibility check of the release state L can be performed, for example, by detecting the position of the projection 9 in the release state L by a further sensor 11. This further sensor 11 then detects the release state L by activating the further sensor 11.

[0048] In such an embodiment, which is not shown but is easily conceivable, two sensors 11 are arranged in the interior space 3 of the housing 2 such that one of the two sensors 11 detects the release state L and the other of the two sensors 11 detects the application state A.

[0049] The sensor 11 is connected to a control unit 17 via an electrically conductive connecting line 16. The control unit 17 supplies the sensor 11 with electrical energy via the connecting line 16 and receives signals from the sensor 11 as brake state signals. The signals from the sensor 11 correspond to the respective brake state of the service brake cylinder 1, namely the release state L and the application state A, and can be further processed by the control unit 17, such as amplified, shaped, etc. In the simplest case, these brake state signals are digital switching signals ("ON", "OFF"), i.e., one state is represented by the presence of a signal amplitude, e.g., a voltage or current value, and the other state by the absence of a signal amplitude, e.g., a voltage or current value. Intermediate values ​​are not required.Of course, the two states can also be represented by different electrical voltages and / or currents, resistances, frequencies, etc.

[0050] Then, a forwarding takes place via a connection 18 via a further control unit 19 by means of a further electrically conductive connection 20 to an evaluation unit 21.

[0051] The evaluation unit 21 outputs an output signal at an output 22, for example, as a visual, acoustic, or haptic indication of the braking status A, L. For example, a screen display of an entire train braking system can be provided, clearly showing the braking status of each service brake cylinder 1. The output signal can also be stored or otherwise processed.

[0052] The evaluation unit 21 is also connected via a connection 23 to a higher-level brake control system (not shown), from which the evaluation unit 21 receives brake application and release signals in order to compare them with the respective detected braking states of the service brake cylinders 1. Of course, other data can also be exchanged.

[0053] in the Figure 1 A further control unit 17' with a connecting line 16' for a further sensor 11 (not shown) and a connection 18' is specified. This further sensor 11 can be arranged, for example, as a second, redundant sensor 11 in the service brake cylinder 1. Two more such sensors 11 can also be provided.

[0054] In addition, the additional control unit 17' is intended to represent a number of control units 17 required for a complete braking system of a train, to which the service brake cylinders 1 are assigned, with a number of service brake cylinders 1 with respective brake state detection devices 10 with corresponding brake state signals. This number of brake state signals of the entire braking system is prepared in the additional control unit 19, e.g., also in conjunction with data from the higher-level brake control system via an additional connection 23a, for simple and rapid evaluation in the evaluation unit 21.

[0055] The sensor 11 can be a contact and / or contactless sensor 11.

[0056] The sensor 11 is well protected from weather influences and damage in the interior 3 of the housing 2 of the service brake cylinder 1. The sensor 11 is accessible from the outside for maintenance, e.g., through a resealable maintenance opening.

[0057] The shape and materials of sensor 11 are designed to maximize its efficiency. For this purpose, certain plastics can be used as the housing, which are resistant to the media found in the service brake cylinder 1, such as lubricant. Furthermore, suitable metallic shielding of sensor 11 can improve its electromagnetic compatibility with interference.

[0058] Figure 2 a schematic flow diagram of a method according to the invention for detecting a braking state of a service brake cylinder 1 according to Figure 1 represents.

[0059] In a first method step V1, a brake condition detection device 10 is provided in a service brake cylinder 1. A sensor 11 of the brake condition detection device 10 is supplied with electrical energy.

[0060] Then, in a second method step V2, electrical signals from the sensor 11 are generated as brake state signals depending on a brake state, namely application state A and release state L, by the sensor 11.

[0061] In a third method step V3, the brake state signals thus obtained are output as detected brake state application state A or release state L.

[0062] Figure 3 shows a schematic flow diagram of a further method according to the invention for detecting a braking state of a service brake cylinder 1 according to Figure 1 .

[0063] The process steps V1, V2 and V3 correspond to those of the process according to Figure 2 .

[0064] In addition, in a subordinate method step V2-1 of the second method step V2, the brake state signals generated by the sensor 11 are plausibly checked by at least one further sensor 11.

[0065] In an additional subordinate method step V3-1 of the third method step V3, the output brake states A, L are further checked with signals for applying and / or releasing the service brake cylinder 1 of a higher-level brake control, and an alarm is output if, after receiving a signal for applying the service brake cylinder 1, no application state A is detected, or / and if, after receiving a signal for releasing the service brake cylinder 1, no release state L is detected.

[0066] The invention is not limited by the embodiment given above, but can be modified within the scope of the claims.

[0067] For example, it is conceivable that the sensor 11 and / or the redundant sensor(s) 11 are based on an optical distance measuring principle, such as a reflective light barrier, laser, on an acoustic distance measuring principle, such as ultrasound, or on an electromagnetic distance measuring principle, such as radar.

[0068] The connections 18, 18', 20, 23, 23a can also be optical conductors and / or wireless transmission links, depending on the application. List of reference symbols

[0069] 1Service brake cylinder 2Housing 2aRear wall 2bFront wall 3Interior 4- n / a - 5Spindle 6Brake pad 7Thrust ring 8Spindle housing 9Protrusion 10Brake condition detection device 11Sensor 12Detection side 13Connection section 14Fastening section 15Bracket 16, 16'Connecting cable 17, 17'; 19Control unit 18, 18'; 20Connection 21Evaluation unit 22Output 23, 23aConnection AApply position / apply state LRelease position / release state V1 ...3; 2-1; 3-1Process step xDirection of movement

Claims

1. Service brake cylinder (1), in particular of a block brake, having a housing (2) with a spindle (5) and a brake state detection apparatus (10) for detecting an applied state (A) and a released state (L) of the service brake cylinder (1), wherein the brake state detection apparatus (10) is arranged completely enclosed within an interior space (3) of the service brake cylinder (1) by the housing (2) and detects the position of the spindle (5), wherein the brake state detection apparatus (10) detects the position of a pressure ring (7) or a spindle housing (8), which are connected to the spindle (5), wherein the brake state detection device (10) has at least one sensor (11), which is arranged in an interior space (3) of the housing (2) of the service brake cylinder (2) between a front wall (2b) and a projection (9) of the spindle housing (8), characterised in that a further sensor (11) is arranged in the interior space (3) of the housing (2), which validates the plausibility of at least one brake state signal of the at least one sensor (11) with the aid of at least one further brake state signal generated by the at least one further sensor (11).

2. Service brake cylinder (1) according to claim 1, characterised in that the at least one sensor (11) is attached by means of a fastening section (14) to a bracket (15), wherein an axial position of the at least one sensor (11) is adjustable on the bracket (15).

3. Service brake cylinder (1) according to claim 1 or 2, characterised in that the at least one sensor (11) interacts with the projection (9) of the spindle housing (8) such that the at least one sensor (11) is activated depending on the position of the projection (9) of the spindle housing (8) in the applied state (A) of the service brake cylinder (1) and is not activated in the released state (L) of the service brake cylinder (1).

4. Service brake cylinder (1), according to any one of claims 1 to 3, characterised in that the at least one sensor (11) is configured as an inductive proximity sensor or proximity switch.

5. Service brake cylinder (1) according to any one.of claims 1 to 4, characterised in that the at least one sensor (11) is a contact and / or contactless sensor (11).

6. Method for detecting a brake state of a service brake cylinder (1) according to any one of the preceding claims, with the method steps of (V1) providing a brake state detection apparatus (10) and arranging the brake state detection apparatus (10) within the service brake cylinder (1) and supplying at least one sensor (11) of the brake state detection apparatus (10) with electric power, (V2) generating at least one electrical signal as a brake state signal depending on a brake state, namely an applied state (A) and / or released state (L), by the sensor (11), and (V3) outputting a detected brake state as an applied state (A) or released state (L) of the service brake cylinder (1) with the aid of the brake state signal detected in this way, characterised in that in the method step (V2), the at least one brake state signal generated by the at least one sensor (11) is validated for plausibility with the aid of at least one further brake state signal generated by at least one further sensor (11) in a secondary method step (V2-1).

7. Method according to claim 6, characterised in that the brake states (A, L) outputted as an applied state (A) or released state (L) of the service brake cylinder (1) in the method step (V3) are checked in a secondary method step (V3-1) with signals for applying and / or releasing the service brake cylinder (1) of a secondary brake control, and an alarm is output if, after receiving a signal to apply the service brake cylinder (1), an applied state (A) is not detected, or / and if, after receiving a signal to receive the service brake cylinder (1), a released state (L) is not detected.