Fluid power system with a monitoring device, painting device and method for detecting volume flow losses

Abstract

The following embodiments relate to a fluid power system (10) with an automated monitoring device (12), comprising: at least one pump unit (14) for providing a pressurized fluid; at least one consumer (D1) operable by the pressurized fluid; at least one supply line (16) for supplying the pressurized fluid; at least one valve unit (V1) for blocking or releasing the pressurized fluid; wherein the monitoring device (12) has a sensor unit (18) for continuously measuring the volume flow of the fluid within the supply line (16) and a control unit (20) for receiving and evaluating the volume flow measured by the sensor unit (18); wherein the control unit (20) is designed to store a fluid consumption of the at least one consumer (D1) at a first time as a reference value for leak-free operation of the fluid power system (10);wherein the control unit (20) is further designed to continuously compare the fluid consumption of the at least one consumer (D1) with the reference value and, in the event of a predetermined deviation from the reference value, to generate a warning signal and to transmit it to an external receiving unit (22);

Description

[0001] The following statements relate to a fluid power system with an automated monitoring device for detecting volume flow losses, which allows wear-related leaks in the system to be detected at an early stage. Furthermore, the following statements relate to a painting device with the fluid power system and a method for detecting volume flow losses in the fluid power system.

[0002] EP 2 047 117 B1 discloses a method for fault isolation and diagnosis in a fluid power system, wherein the volume flow of the entire system or a sub-area, as well as the fluid pressure, are recorded during an operating cycle and compared with stored references. US 2003 / 0 187 595 A1 relates to a monitoring system for compressed air circuits in production systems that automatically and continuously detects leaks. DE 10 2017 122 493 A1 describes a print head for applying coating agents, in particular paint, to components such as vehicle bodies.

[0003] There is a constant need to reduce maintenance intervals and wear-related downtime of fluid power systems.

[0004] Based on this situation, the present task is to propose a fluid power system in which the early detection of wear phenomena can be improved and downtime can be avoided.

[0005] The present object is achieved by the features of the independent claims. Advantageous embodiments are specified in the subclaims, the description, and the drawings. To the extent technically feasible, the teachings of the subclaims may be combined arbitrarily with the teachings of the main and subclaims.

[0006] In particular, the object is accordingly achieved by a fluid power system with an automated monitoring device for detecting volume flow losses, comprising: at least one pump unit for providing a pressurized fluid for operating a plurality of consumers; a plurality of consumers operable by the pressurized fluid; at least one supply line for supplying the pressurized fluid from the pump unit to the plurality of consumers; at least one valve unit for blocking or releasing the pressurized fluid for operating the plurality of consumers; wherein the monitoring device comprises a sensor unit for continuously measuring the volume flow of the fluid within the supply line and a control unit for receiving and evaluating the volume flow measured by the sensor unit.wherein the control unit is configured to store a plurality of reference values ​​for the fluid consumption of the fluid power system (10) for each consumer individually and in combination with one another during leak-free operation of the fluid power system; wherein the control unit is further configured to continuously compare the fluid consumption of the fluid power system (10) with the stored reference values ​​and, in the event of a predetermined deviation from one of the reference values, to generate a warning signal and transmit it to an external receiving unit.

[0007] The pressurized fluid provided by the at least one pump unit can be transported to the plurality of consumers via the at least one supply line. The monitoring device has a sensor unit for monitoring the volume flow. The sensor unit can in particular be located on the supply line or integrated into the supply line or formed as part of the supply line. At least one valve unit is arranged between the sensor unit and the consumers, which blocks the fluid flow in the supply line as required or releases it for the operation of the respective consumer. Depending on the design, the respective consumer exerts a specific resistance on the fluid or the fluid flow. This results in a unique volume flow during operation, which can be measured by the sensor unit and stored by the control unit as a reference value.Wear-related leaks can cause the flow rate to increase over time. The deviation detected by the control unit can be within a predetermined tolerance range. Outside this tolerance range, the control unit generates a warning signal and transmits it to an external receiving unit. Deviations to lower flow rates can be ignored or taken into account. To detect even sudden leaks, the flow rate in the system is continuously monitored. This allows maintenance needs to be identified quickly and lengthy downtimes to be avoided.

[0008] Advantageous aspects are explained below, and preferred modified embodiments are described further below. Explanations, particularly regarding advantages and definitions of features, are essentially descriptive and preferred, but not limiting, examples. If an explanation is limiting, this will be expressly stated.

[0009] It is preferred that the sequence of process steps can be varied, unless technically required in an explicit order. However, the aforementioned sequence of process steps is particularly preferred.

[0010] The stored reference values ​​can also be plotted as a function of time. This is particularly advantageous for systems in which the volume flow changes over time due to operational reasons. Continuous monitoring of the system refers to monitoring during operation of the fluid power system. If the system is deactivated, no measurement is performed. The term "volume flow" is synonymous with the term "fluid consumption" in this application. The unit in which the volume flow is measured is usually m. 3 / min or l / min. The sensor unit is designed specifically as a flow sensor or volume flow sensor.

[0011] If there are a large number of consumers, the reference values ​​are determined for each consumer individually and in combination with each other. For example, the control unit stores three reference values ​​for two consumers and uses them for comparison. One reference value refers to the volume flow of the first consumer when it is operated alone. Another reference value refers to the volume flow of the second consumer when it is operated alone. And the third reference value refers to the volume flow for both consumers when they are operated together. Advantageously, this means that the operating mode of the individual consumers does not have to be known to the control unit for the subsequent comparison of the measured fluid consumption with the reference values. Because of the different reference values, it is sufficient to compare the received data with these.

[0012] Alternatively or additionally, it can be provided that the predetermined deviation is at least 5%, preferably at least 10%, in particular at least 15% of the reference value. Smaller deviations can be system-related and wear-independent fluctuations that do not require maintenance of the system. In particular, it is provided that the volume flow measurement and / or the evaluation of the measured volume flow by the control unit is suspended for a predetermined period of time in order to mask out volume flow fluctuations caused by the switching cycles of the consumers. The predetermined period of time can in particular be at least 3 seconds, preferably at least 5 seconds, particularly preferably at least 10 seconds.

[0013] Alternatively or additionally, the fluid can be a liquid or, preferably, a gas, in particular air. The term "air" refers to the ambient air provided by the at least one pump unit as a pressurized fluid for operating at least one consumer. The pump unit is designed, in particular, as a compressed air generator.

[0014] Alternatively or additionally, it can be provided that at least one consumer is designed as an actuator, drive or nozzle. With the fluid power system described above, a large number of consumers can be driven or controlled. In particular, the fluid power system can have a combination of different consumers. In particular, for use of the fluid power system in a painting device, at least one consumer is designed as an actuator or nozzle for spraying paints and varnishes. In particular, for use of the fluid power system in a motor vehicle, at least one consumer is designed as an actuator for releasing locks or as a drive for moving windows or body components. Due to the large number of possible applications of the fluid power system described above, at least one consumer can be designed beyond the exemplary embodiments mentioned above.

[0015] Alternatively or additionally, the external receiving unit can be an alarm center and / or a system visualization system. An alarm center can be understood as a control center, a computer system, a cloud, or the like. In particular, manual or automated maintenance of the system can be commissioned via the alarm center. In particular, this makes it possible to order wear components for upcoming maintenance before a wear-related system failure occurs. In particular, it is provided that the warning signal is designed as an analog or digital signal and includes information about the measured fluid consumption. In particular, it is provided that the warning signal can be transmitted to the external receiving unit in the form of an email, SMS, and / or telephone call.This allows a loss of volume flow to be indicated immediately after it is detected by the control unit and measures to rectify the problem can be taken.

[0016] Alternatively or additionally, it can be provided that the at least one supply line is designed as a hose, pipe, or a combination of both. Hoses, in particular plastic hoses, and pipes, in particular plastic and metal pipes, are well suited for transporting fluids. Plastic hoses have the advantage of being flexible and easy to install. Pipes, on the other hand, can be more wear-resistant and can transmit high pressures. The use of plastic and / or metal exposes the at least one supply line to various forms of wear, which can lead to volume flow losses during operation. The fluid power system mentioned above allows any weakening of these components to be detected at an early stage, thus preventing system failure.

[0017] The object is further achieved by a painting device comprising a fluid power system, which can be designed and developed as described above. Painting devices, especially fully automated painting devices in automotive production, are in constant operation. Unplanned downtimes due to wear or manufacturing defects caused by a drop in volume flow are generally associated with high costs. Continuous measurement of the volume flow as described above can prevent this.

[0018] The object is further achieved by a method according to claim 8.

[0019] A preferred technical solution is explained in more detail below with reference to the accompanying drawings using preferred embodiments. The term "figure" is abbreviated to "Fig." in the drawings.

[0020] The drawings show Fig. 1 a schematic view of a first embodiment of a fluid power system.

[0021] The described embodiments are merely examples that can be modified and / or supplemented in a variety of ways within the scope of the claims. Each feature described for a specific embodiment can be used independently or in combination with other features in any other embodiment. Each feature described for an embodiment of a specific claim category can also be used correspondingly in an embodiment of a different claim category.

[0022] Fig.Figure 1 shows a schematic view of a first embodiment of a fluid power system 10 with an automated monitoring device 12 for detecting volume flow losses. The fluid power system 10 has a pump unit 14 for providing a pressurized fluid for operating a plurality of consumers D1, D2, D3, ..., D n and a supply line 16 for supplying the pressurized fluid from the pump unit 14 to the consumers D1, D2, D3, ..., D n . For monitoring the volume flow, the monitoring device 12 has a sensor unit 18, which is formed as part of the supply line 16. Between the sensor unit 18 and the consumers D1, D2, D3, ..., D n is each consumer D1, D2, D3, ..., D n a valve unit V1, V2, V3, ..., V narranged upstream, which blocks the fluid flow in the supply line 16 as required or for the operation of the consumers D1, D2, D3, ..., D n The monitoring device 12 further comprises a control unit 20 for receiving and evaluating the volume flow measured by the sensor unit 18, wherein the control unit 20 is designed to control the fluid consumption of the consumers D1, D2, D3, ..., D n individually and in combination with each other at a first point in time as reference values ​​for leak-free operation of the fluid power system. The control unit 20 is further configured to measure the fluid consumption of the consumers D1, D2, D3, ..., D n to continuously compare with the reference values ​​and, in the event of a predetermined deviation from the stored reference values, to generate a warning signal and transmit it to an external receiving unit 22.

Claims

[1] Fluid power system (10) with an automated monitoring device (12) for detecting volume flow losses, comprising: at least one pump unit (14) for providing a pressurized fluid for operating a plurality of consumers (D1, D2, D3, ..., D n ); a plurality of consumers operable by the pressurized fluid (D1, D2, D3, ..., D n ); at least one supply line (16) for supplying the pressurized fluid from the pump unit (14) to the plurality of consumers (D1, D2, D3, ..., D n ); at least one valve unit (V1) for blocking or releasing the pressurized fluid for the operation of the plurality of consumers (D1, D2, D3, ..., D n ); wherein the monitoring device (12) has a sensor unit (18) for continuously measuring the volume flow of the fluid within the supply line (16) and a control unit (20) for receiving and evaluating the volume flow measured by the sensor unit (18); wherein the control unit (20) is designed to store a plurality of reference values ​​for the fluid consumption of the fluid power system (10) for each consumer (D1, D2, D3, ..., Dn) individually and in combination with one another during leak-free operation of the fluid power system (10); wherein the control unit (20) is further designed to continuously compare the fluid consumption of the fluid power system (10) with the stored reference values ​​and, in the event of a predetermined deviation from one of the reference values, to generate a warning signal and to transmit it to an external receiving unit (22). [2] Fluid power system (10) according to claim 1, wherein the predetermined deviation is at least 5%, preferably at least 10%, in particular at least 15% of the reference value. [3] Fluid power system (10) according to one of the preceding claims, wherein the fluid is a liquid or preferably a gas, in particular air. [4] Fluid power system (10) according to one of the preceding claims, wherein at least one consumer (D1, D2, D3, ..., D n ) is designed as an actuator, drive or nozzle. [5] Fluid power system (10) according to one of the preceding claims, wherein the external receiving unit (22) is an alarm center and / or a system visualization, wherein in particular the warning signal is designed as an analogue or digital signal and includes information about the measured fluid consumption, wherein in particular the warning signal can be transmitted to the external receiving unit (22) in the form of an e-mail, SMS and / or telephone call. [6] Fluid power system (10) according to one of the preceding claims, wherein the at least one supply line is designed as a hose, pipe or a combination of both. [7] Painting device comprising a fluid power system (10) according to one of claims 1 to 6. [8] A method for detecting volume flow losses in a fluid power system (10) according to any one of claims 1 to 6, the method comprising the following steps: - Measuring the volume flows within the supply line (16) for a large number of consumers (D1, D2, D3, ..., D n ) individually and in combination with each other by the sensor unit (18) at a first time, wherein the first time represents a leak-free operation of the fluid power system (10); - storing the measured volume flows as reference values ​​by the control unit (20); - continuous measurement of the volume flow within the supply line (16) by the sensor unit (18) and transmission of the measurement data to the control unit (20); - continuous reception and comparison of the measurement data with the reference values ​​by the control unit (210); - upon detection of a predetermined deviation from at least one reference value, generation of a warning signal by the control unit (20); - Transmission of the warning signal to an external receiving unit 22).

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