Hydraulic component

Abstract

Hydraulic component, characterized in that at least one camera (12, 33, 46, 64) is integrated into it, which is arranged such that at least one wearable surface (31) and / or at least one wearable edge (10) can be observed via it.

Description

Field of the invention

[0001] The invention relates to a hydraulic component according to the preamble of claim 1. Background of the invention

[0002] Hydraulic components, such as axial piston machines or valves, are subject to wear. For example, an axial piston machine can experience wear due to cavitation damage. To detect this damage as early as possible and prevent unforeseen failures of the hydraulic component, it can be monitored. Furthermore, monitoring the component allows for better planning of maintenance intervals.

[0003] Monitoring the hydraulic component includes, for example, measuring the temperature and / or the water content in the hydraulic fluid and / or recording vibrations. This data can be used, for example, to determine wear on the hydraulic component. However, it is not possible to determine the exact location where the hydraulic component is defective and / or worn by measuring this data. Furthermore, the aforementioned data indicating wear can also be generated, for example, by another hydraulic component contained in a hydraulic assembly in which the hydraulic component is included.

[0004] DE 10 2017 118 914 A1 discloses a system for determining the wear of abrasive elements on a bucket wheel machine. Bucket wheel machines are conventional bucket wheel excavators or bucket wheel machines suitable for conveying material, for example, to or from a stockpile, which also includes so-called bucket wheel reclaimers. A recording unit is used to generate an image of the buckets to be monitored and the abrasive elements arranged on the buckets, in particular the bucket teeth. The image is created using a camera, preferably a still camera, a thermal imaging camera, a radar sensor, an ultrasonic sensor, or a laser sensor.

[0005] DE 199 24 607 A1 discloses a remote-controlled inspection device for an annular combustion chamber of a gas turbine. The inspection device comprises a remote-controlled drive mechanism, a movable video camera, a lighting device, a support frame for the video camera, and means for transmitting video images from the video camera to an evaluation device. The annular combustion chamber must be regularly inspected for signs of wear. For this purpose, the remote-controlled inspection device is inserted into the annular combustion chamber.

[0006] The subsequently published FR 3 096 092 A1 describes a device for inspecting a hydraulic component of a turbomachine. By means of this device, a flow circuit is formed which, among other things, has a test area for receiving the hydraulic component, wherein a working fluid can be pumped through the test area. The hydraulic component can be a valve or a kinetic pump, a jet pump or a positive displacement pump. The performance of the hydraulic component can be examined in the test area. In particular, the performance of the hydraulic component under cavitation can be examined, wherein by introducing gas into the working fluid the cavitation behavior of the hydraulic component is simulated as it would occur in real use of the hydraulic component, for example with kerosene as the fluid.The test area has transparent walls so that images of the working fluid flowing through the test area and the hydraulic component can be captured using a camera.

[0007] In contrast, the invention is based on the object of creating a hydraulic component which is simple in terms of device technology and cost-effective, the condition of which, in particular the state of wear, can be monitored cost-effectively, simply in terms of device technology and precisely.

[0008] This problem is solved according to the characteristics of objection 1.

[0009] Advantageous further developments of the invention are the subject of the subclaims.

[0010] According to the invention, a hydraulic component is provided into which at least one camera is integrated. This camera is directed, in particular, at a wear-prone surface and / or at least one wear-prone edge, so that these can be observed. In other words, the camera is arranged such that at least one surface and / or at least one edge can be observed via it. For example, the camera can be integrated into an axial piston machine, and via this camera, for example, a sliding surface on a cylinder drum of the axial piston machine can be observed.

[0011] One advantage of the invention is that the camera, which is directed at the surface and / or the edge and / or via which the edge and / or surface can be observed, makes the wear status of this edge and / or this surface visible. In other words, a wear statement does not have to be calculated and / or estimated based on various measured data, but the wear statement can be made reliably and precisely. A further advantage is that the section and / or component in which or on which wear has occurred can be determined using the camera. This has the advantage that the defective component is already known before maintenance, i.e. before the hydraulic component is unscrewed for maintenance, for example, and thus the defective component can be prepared and / or ordered and / or manufactured in advance. This can save time during a maintenance process on the hydraulic component.A further advantage is that no complicated calculations and / or estimates are required to determine wear. In other words, computer systems that determine wear from measured data can be omitted, as wear can be determined using images captured by the camera. Additionally, in a hydraulic system that has several of these hydraulic components, it is possible to directly determine which hydraulic component is defective and is causing, for example, an increased temperature of a hydraulic fluid. In other words, a multitude of different operating data no longer needs to be monitored in order to determine which hydraulic component is defective and what the defect is.

[0012] The hydraulic component preferably has an evaluation unit and / or is connected to an evaluation unit. The evaluation unit can evaluate the image and / or images from the camera, and thus a wear statement can be made about the surface and / or the edge. In other words, the camera can be connected to the evaluation unit and / or a server, for example, via a cable that can be led out of the hydraulic component, for example, and / or wirelessly, for example via Bluetooth or another wireless connection technology, in order to be able to make an accurate wear statement. And / or the server can also be connected to the evaluation unit wirelessly and / or via a cable.The evaluation unit can, for example, be configured to provide wear information, such as whether the hydraulic component is worn and / or where the hydraulic component is worn and / or how advanced the wear is. This is advantageous because the wear information is very accurate and maintenance can be adjusted accordingly. In other words, a maintenance interval can be extended, for example, if the evaluation unit has determined from the camera images that the hydraulic component shows no wear and / or only minimal wear, making maintenance unnecessary.

[0013] The evaluation unit can, for example, have a monitor or display and / or be connected to a monitor or display, and a person can, for example, evaluate the data via this monitor. For example, the images from the camera can be transmitted to a server, in particular a condition monitoring server, and stored there. A person can then view this data, for example, on a screen and / or display, and thus make a statement about wear.

[0014] In a further embodiment, the evaluation unit can additionally or alternatively comprise an automated image evaluation unit. The automated image evaluation unit can, for example, use a neural network to determine a wear condition based on image features. In other words, the automated image evaluation can, for example, compare images of the surface and / or edge captured by the camera with images and / or an image of the surface and / or edge in an unused state. The automated image evaluation unit can detect even the smallest changes, and the wear assessment can be made with particular accuracy.A further advantage is that the automated image evaluation unit can perform the analysis without human supervision. If wear occurs, the automated image evaluation unit can, for example, automatically perform a follow-up step, such as requesting maintenance and / or issuing a wear warning. This can, for example, save personnel costs.

[0015] In particular, the automated image analysis unit is based on a neural network, in particular a convolutional neural network (CNN). The neural network is particularly suitable for analyzing images. For this purpose, the neural network can have a structure with different layers. For example, the neural network can consist of one or more convolutional layers followed by a pooling layer. These layers can be repeated as often as required, i.e. in particular as often as is necessary for the application in question. A fully connected layer can then be added. It is advantageous to integrate such a neural network into the analysis unit because it can, for example, learn independently and thus the wear information becomes more and more accurate and better over time. Furthermore, complicated training of the automated image analysis unit is therefore not necessary or only required to a limited extent.

[0016] Furthermore, at least one additional sensor can be provided. This can, for example, be configured to determine operating data such as an ambient temperature and / or a temperature of the hydraulic fluid and / or the air humidity and / or vibrations and / or an oxygen content in the hydraulic fluid and / or a water content in the hydraulic fluid, etc. Additionally or alternatively, a movement speed, for example the number of revolutions per minute in an axial piston machine, can also be determined by the sensor. This operating data can, for example, be communicated to the evaluation unit, in particular via the server. The evaluation unit can then use the operating data to make a wear statement about the hydraulic component.In other words, in the wear assessment made based on the camera images, a further wear assessment can be determined from the operating data. This is advantageous because it allows the wear assessment to be verified. Furthermore, the sensor can preferably be connected to the evaluation unit via a cable or wirelessly, and / or the sensor can be connected to the server via a cable or wirelessly.

[0017] Furthermore, the evaluation unit is preferably configured to compare the wear assessment based on the operating data with the wear assessment based on the images. In other words, the evaluation unit automatically compares the two wear assessments to verify the wear assessment and to make the wear assessment more accurate and less susceptible to errors. In other words, a wear assessment can be made more reliably. For example, a warning message and / or maintenance due to an incorrect assessment can be prevented. This can lead to savings in labor and material costs.

[0018] Furthermore, the hydraulic component and / or the camera has at least one light source. In other words, at least one light source is arranged in the hydraulic component, for example, in the camera, such that the edge and / or the surface is illuminated. This is advantageous because it results in better exposure of the images captured by the camera.

[0019] To accommodate the camera and / or the light source, the hydraulic component can have at least one recess. The recess can be arranged, for example, in a connection cover of an axial piston machine.

[0020] If the camera is supplied with power from the outside via a cable and / or the camera is connected to the server and / or the evaluation unit, for example, by a cable, the recess is preferably a through-hole. The through-hole can in particular have different sections with different diameters, wherein in particular a diameter provided for the passage of the cable is smaller than a section for accommodating the camera and / or the light source. In other words, using the example of the axial piston machine, the camera and / or the light source can be inserted into the through-hole and / or the recess, in particular from one side, such that the through-hole and / or the recess can be sealed particularly simply and easily from the outside. For this purpose, the camera and / or the light source can, for example, be attached when the hydraulic component is not yet assembled.In summary, the recess preferably has a larger diameter on the side facing the observable surface and / or edge than on the side facing away from it, so that the recess can be easily sealed to the outside.

[0021] Preferably, at least one computing element is provided, which can be integrated into the evaluation unit, for example. The computing element is preferably configured such that it controls the light source or the camera depending on the operating data of the hydraulic component determined by the sensor. In particular, the sensor controls the camera and / or the light source depending on a movement speed of the hydraulic component. This means that the hydraulic component preferably has at least one speed sensor. This is advantageous because it allows the light and also the triggering of the camera to be synchronized with a movement of the hydraulic component. For example, in an axial piston machine, the computing element can control the camera or the light source such that a sliding surface on a cylinder drum is visible in the image taken by the camera.In other words, the camera can capture only relevant images, thus reducing the server's memory size, for example. If the camera were triggered independently of the movement of the hydraulic component, a large number of images would be generated that would not provide any information about wear. These images would have to be sorted out, for example, which would involve a significant amount of work. Therefore, it is advantageous for the computing element, the camera, and / or the light source to be synchronized with the movement of the hydraulic component.

[0022] If the movement of the hydraulic component is very fast, the light source is preferably a stroboscope. This is advantageous because, for example, an image visible to the human eye is a still image, particularly showing the worn surface and / or edge.

[0023] Furthermore, it is advantageous if the hydraulic component and / or the camera have a transparent element, which can be a pane, for example. The element can protect the light source and / or the camera from dirt and / or hydraulic fluid. In other words, the element is arranged between the surface and / or edge to be photographed and / or recorded and the camera and / or the light source. The element is preferably arranged in the component via a sealing means and seals a receiving space for the camera and / or the light source.

[0024] Furthermore, the hydraulic component can be, for example, a piston accumulator, in which the camera can be used to inspect an inner surface and to detect leaks, and / or a directional control valve, in which the camera can be used to detect wear on the control edges, and / or a control valve, in which the camera can be used to detect wear on the control edges, and / or a servo-hydraulic axis, and / or a cylinder, in which surface wear and leak detection can be carried out by the camera, and / or an assembly, in which the camera can be used to detect foam formation, etc. in the container interior. In other words, the hydraulic component can be a respective hydraulic component that has moving parts.

[0025] If the hydraulic component is a directional control valve, for example, the camera and / or the light source can be located in, for example, a valve housing of the directional control valve. The camera is then preferably aligned such that a valve spool and / or control edges of the valve can be observed above it.

[0026] If the camera is located in an axial piston machine, for example, it can preferably be arranged in a connection cover. The camera can be used to observe, for example, a sliding surface, in particular a sliding surface on the cylinder drum. In particular, the camera can be arranged in an additional recess, for example, in an inlet and / or outlet line in the connection cover. If the camera is arranged there, it can, for example, record the sliding surface through at least one opening in a control disk. Short description of the characters

[0027] Preferred embodiments of the invention are explained in more detail below with reference to schematic drawings. They show: Fig. 1 a sectional view of a directional control valve with a camera, Fig. 2 a sectional view of an axial piston machine with a camera, Fig. 3 a schematic drawing of a camera in an installed state, Fig. 4 a schematic structure of a hydraulic component with an evaluation unit, and Fig. 5 a process of evaluating an evaluation unit.

[0028] Fig. Figure 1 shows a directional control valve 1, which is a hydraulic component and also has a pilot valve 2. The directional control valve 1 has a continuously adjustable valve spool 4 that is movable within a valve housing 6. Springs 8, which are arranged on either side of the valve spool 4, are each supported on the valve housing 6 and on a respective side of the valve spool 4, so that the valve spool 4 is spring-centered in a central position in a non-actuated state.

[0029] The valve spool 4 and the valve housing 6 have a plurality of control edges 10. These are susceptible to wear. Therefore, monitoring the control edges 10 can prevent, for example, the directional control valve 1 from unexpectedly failing. To monitor the control edges 10 or at least some of the control edges 10, a camera 12 is inserted into the valve housing 6. The camera 12 is arranged such that it can observe the control edges 10. For this purpose, the valve housing 6 has an additional recess 14 that accommodates the camera 12. The camera 12 is aligned in a radial direction of the valve spool 4. In addition, the recess 14 can accommodate a cable 15, with which the camera 12 can be connected, for example, to a computing unit and / or an evaluation unit.

[0030] In order to accommodate the camera 12, the recess 14 can, for example, be a through-bore through the valve housing 6, which has a slightly larger diameter than the camera 12 so that the camera can be arranged through the recess 14 from the outside, so that it is directed towards the control edges 10. In this case, the recess 14 can, for example, be sealed with a sealant on the side facing the control edges 10 so that no hydraulic fluid can escape. Furthermore, the recess 14 can have different diameters, with the recess 14 on the side facing the control edges 10 having a diameter large enough to accommodate the camera 12. The diameter of a part of the recess 14 through which the cable 15 can be guided preferably has a smaller diameter so that the recess 14 can be easily sealed to the outside.If the recess 14 has a smaller diameter on the side facing away from the control edges 10, the camera 12 can be inserted, for example, through a bore in which the valve slide 4 is arranged in the assembled state.

[0031] In Fig. 2, an axial piston machine 16, which is a hydraulic component, is shown in a longitudinal section. A drive shaft 18 of the axial piston machine 16 is rotatably mounted via a rolling bearing 19 in a housing 20 of the axial piston machine 16. A cylinder drum 21 is connected to the drive shaft 18 in a rotationally fixed manner. Cylinder bores 22 are formed in the cylinder drum 21, offset on a pitch circle. A piston 23 is arranged in each of these for axial displacement. Each piston 23 is connected to a sliding block 25 via a ball joint connection 24 and is supported by the latter on a pivoting cradle 26. The cylinder bores 22 are connected to a high-pressure side (not shown) of the axial piston machine 16 and a low-pressure side (also not shown) via a control plate 28. The stroke of the pistons 23 in the cylinder bores 22 is predetermined by a pivoting angle of the pivoting cradle 26. According to Fig. 2, the pivoting cradle 26 is shown in its minimally pivotable state.

[0032] A connection cover 29 is connected to the control plate 28, which can connect the axial piston machine 16 to a hydraulic system (not shown here). The connection cover 29 has openings 30 that are connected to the cylinder bores 22 via openings 31 in the control plate 28. The openings 30 are, for example, inlet and / or outlet openings. The cylinder bores 22 have sliding surfaces 32 on which the pistons 23 slide. These surfaces can wear due to cavitation, for example. It is therefore advantageous to observe them via a camera 33. The camera 33 is installed in a recess 34, which is connected to the opening 30 during manufacture. Via the camera 33, which in this case is aligned parallel to an axial axis of the axial piston machine 16, the sliding surfaces 31 of the cylinder bores 22 can be observed through the opening 30 and via the openings 31 of the control plate 28.The recess 34 has two sections with different diameters. A first section of the recess 34 has a diameter such that the camera 33 can be arranged therein. The camera 33 can, for example, be inserted through the opening 30 into the recess 34. A cable 38, through which the camera 33 can be connected to a power source and / or an evaluation unit 40 and / or a computing unit 42, can be guided outward through the recess 34 from the camera 33. A section of the recess 34 through which the cable 38 is guided can, since the camera 33 can be inserted through the opening 30, have a smaller diameter than the section in which the camera 33 is arranged. As a result, the recess 34 can be easily sealed off from the outside at the section with the smaller diameter.

[0033] In addition, the connection cover 29 has a further recess 44 in which a light source 45 can be arranged. The light source 45, like the camera 33, can be mounted through the opening 30. The light source 45 can have a battery and / or an accumulator and can be connected, for example, via Bluetooth or another wireless connection option to, for example, the computing element 42. The computing element 42 can control the camera 33 and the light source 45, for example, synchronously with the movement of the axial piston machine 16.

[0034] In Fig. 3 is an exemplary section, for example of the connection cover 34 of the Fig. 2, in which a camera 46 is integrated. The camera 46 is integrated into a recess 48. The recess 48 has three stepped sections, a first section 50 having the smallest diameter, as this is suitable for passing a cable 52 through. The camera 46 is inserted into a second section 54, which has a diameter such that the camera 46 can be integrated therein. Furthermore, the recess has a third section 56, which has a slightly larger diameter than section 54. The camera 46 can be inserted into the recess 48 through section 56, which preferably faces the edge subject to closure and / or the surface subject to wear. Once the camera 46 has been inserted, the recess 48 on the side facing the edge and / or surface subject to wear can be closed with a disk and / or a transparent element 58.A sealing means, such as a gasket, can be arranged around the element 58 to protect the camera 46 from hydraulic fluid and / or dirt. Furthermore, a gasket or sealing means can also be arranged around the cable 52 to prevent hydraulic fluid from escaping through the recess 48.

[0035] Fig. 4 shows a schematic structure of a hydraulic component, which is a hydraulic machine 60 driven by a motor 62. The hydraulic machine 60 draws hydraulic fluid from a tank T. A camera 64 is integrated into the hydraulic machine 60 to observe a worn surface and / or a worn edge (not shown here). Furthermore, several operating data are acquired by various sensors. For example, a pressure sensor 66 is provided that measures the pressure in a pressure line on the output side of the hydraulic machine 60. Furthermore, a speed sensor 68 is provided that measures the speed of a drive shaft 70 of the motor 62 and measures the number of revolutions per minute at which the drive shaft 70 rotates to drive the hydraulic machine 60. In addition, a torque that the motor 62 generates to drive the hydraulic machine 60 is also measured with a torque sensor 72.

[0036] Both the image data recorded by the camera 64 and the operating data are transmitted either wirelessly and / or via a cable to a component 74, which is in particular a gateway and / or a server, which preferably connects the system of the hydraulic machine 60 to an evaluation unit 76. In the evaluation unit 76, the data, i.e. the images and / or the operating data, can be evaluated by the evaluation unit 76. In addition, the evaluation unit can have an automated image evaluation unit 78, which evaluates the images from the camera 64 using a neural network. The evaluation unit 76 can also include a screen 80, via which, for example, a person can evaluate the images and operating data.

[0037] In Fig. 5 is a process that schematically describes how the evaluation unit 76 of the Fig. 4 evaluates the images and / or the operating data. First, in a first step 82, the operating data such as pressure, speed and torque, which are stored for example in Fig. 4 by a pressure sensor 66, a speed sensor 68, and a torque sensor 72. This means that a wear statement is derived from the operating data. In a further step 84, which can be carried out simultaneously or in parallel with step 82, the images from the camera 64 are also evaluated, in particular by a neural network of the automated image evaluation unit 78 of the Fig. 4 and also a wear statement is made. Both wear statements are then compared in a step 86. This means that the evaluation unit compares the wear statement based on the operating data with the wear statement based on the camera images. If, for example, these match and both wear statements are negative, ie, no wear was detected, then, for example, the Fig. 4, a green light is displayed. If both wear indicators are positive, i.e., both wear indications indicate that wear has been detected, a red light and / or a message can be displayed to a person, for example. If the wear indications are different, a message can also be displayed to a person, allowing them, for example, to review the images from camera 64 and thus determine whether wear is present. List of reference symbols 1 directional valve 2 pilot valves 4 valve slides 6 valve housing 8 spring 10 Control edge 12, 33, 46, 64 Camera 14, 34, 44, 48 recess 15, 38, 52 cables 16 axial piston machine 18 Drive shaft 19 rolling bearings 20 housings 21 Cylinder drum 22 cylinder bore 23 pistons 24 ball joint connection 35 sliding shoe 26 swivel cradle 28 Control plate 29 Connection cover 30 openings 31 sliding surfaces 40 Evaluation unit 42 computing unit 45 Light source 50, 54, 56 Section 58 Transparent / transmissive element 60 hydro machine 62 engine 66 Pressure sensor 68 Speed ​​sensor 70 Drive shaft 72 torque sensor 74 Gateway 76 Evaluation unit 78 Automated image evaluation unit 80 screen 82, 84, 86 step

Claims

[1] Hydraulic component, characterized by in that at least one camera (12, 33, 46, 64) is integrated therein, which camera is arranged in such a way that at least one surface (31) subject to wear and / or at least one edge (10) subject to wear can be observed therethrough. [2] Hydraulic component according to claim 1, wherein an evaluation unit (40, 76) is provided, via which an image of the camera (12, 33, 46, 64) can be evaluated in order to make a wear statement about the surface (31) and / or the edge (10). [3] Hydraulic component according to claim 2, wherein the evaluation unit (40, 76) has a screen (80) and / or is connected to a screen (80) so that the data about a person can be evaluated. [4] Hydraulic component according to claim 2 or 3, wherein the evaluation unit (40, 76) comprises an automated image evaluation unit (78). [5] Hydraulic component according to one of claims 2 to 4, wherein at least one sensor (66, 68, 72) is provided, is configured such that it determines operating data of the hydraulic component (1, 16) and wherein the evaluation unit (40, 76) is configured such that a wear statement about the hydraulic component (1, 16) can be made from the operating data. [6] Hydraulic component according to claim 5, wherein the evaluation unit (40, 76) is designed such that it compares the wear statement based on the operating data with the wear statement based on the image. [7] Hydraulic component according to one of claims 1 to 6, wherein this and / or the camera (12, 33, 46, 64) has at least one light source (45) to illuminate the edge (10) and / or the surface (31). [8] Hydraulic component according to one of claims 1 to 7, wherein it has at least one recess (14, 34, 44, 48) for receiving the camera (12, 33, 46, 64) and / or the light source (45). [9] Hydraulic component according to one of claims 1 to 8, including claim 5, wherein a computing element (42) is provided which is configured to control the light source (45) and / or the camera (12, 33, 46, 64) as a function of the operating data of the hydraulic component (1, 16) determined by the sensor (66, 68, 72). [10] Hydraulic component according to one of claims 7 to 9, wherein the light source (45) is a stroboscope. [11] Hydraulic component according to one of claims 1 to 10, wherein this and / or the camera (12, 33, 46, 64) comprises a transparent / transmassive element (58) to protect the camera (12, 33, 46, 64) and / or the light source (45) from dirt. [12] Hydraulic component according to one of claims 1 to 11, wherein it is an axial piston machine (16) or a directional control valve (1) or a control valve or a servo-hydraulic axis or a hydraulic cylinder or a piston accumulator or an aggregate. [13] Hydraulic component according to claim 12, wherein the camera (12, 33, 46, 64) of the directional control valve (1) is arranged in a valve housing (6) such that a control edge (10) can be observed via the camera (12, 33, 46, 64). [14] Hydraulic component according to claim 12, wherein the camera (12, 33, 46, 64) of the axial piston machine (16) is arranged in a connection cover (28) such that a sliding surface (31) can be observed. [15] Hydraulic component according to claim 14, wherein the camera (12, 33, 46, 64) of the axial piston machine is arranged in an inlet and / or outlet channel (30) in the connection cover (29).

Images