Method for evaluating appropriate installation of metering pump and metering pump

Abstract

The method for evaluating the appropriate installation of a metering pump (2) comprises the steps of: a) setting a drive mode to a first mode configuration (PCn), b) operating the metering pump (2) in said drive mode, c) detecting a stroke map (34) during the operation of the metering pump (2) in said drive mode, the stroke map representing a relationship between force and stroke position, d) determining the appropriate installation of the metering pump (2) from at least a portion (38, 38 ') of the detected stroke map (34). 40) deriving at least one first criterion, e) selecting an evaluation step (En + 1) on the basis of the derived criterion by using the decision matrix (36), f) setting the drive mode to a second or further mode configuration (PCn + 1) according to the selected evaluation step (En + i), and repeating steps b) to f) until at least one predetermined final evaluation step (F) in the decision matrix (36) is reached. The invention further relates to a metering pump device configured to carry out the method.

Description

Technical Field

[0001] The present invention relates to a method for assessing the proper installation of a metering pump and to a corresponding metering pump device configured to carry out such a method. Background Art

[0002] Correct installation or extensive knowledge of installation is essential for controlling metering pumps and ensuring their safe operation. Incorrect installation can lead to, for example, undesired cavitation or improper operation. Therefore, correct installation and configuration of pump controls are crucial and require extensive knowledge and experience on the part of designers, installers, and users. Summary of the Invention

[0003] In view of this, the object of the present invention is to simplify the installation of a metering pump and, in particular, to ensure correct installation. This object is achieved by a method having the features defined in claim 1 and by a metering pump device having the features defined in claim 15. Preferred embodiments are defined in the dependent claims, the following description, and the accompanying drawings.

[0004] According to the present invention, a method for assessing the proper installation of a metering pump is provided. This method is performed by an electronic control device to automatically assess the installation or commissioning of a metering pump. The method can be incorporated into the control software of the metering pump, which executes an assessment routine based on the method to assess the correct or proper installation of the pump, for example, before starting operation of the metering pump.

[0005] According to the method, the drive mode of the metering pump is set to a first mode configuration. This drive mode is the mode in which the driver operates the metering pump (particularly the displacement element within the moving pump). In particular, this drive mode defines the speed of the displacement element at different parts of the travel path. This means that the speed can vary during the travel cycle, and / or the pump can stop at one or more predetermined stroke positions. In the first step of the method, the drive mode is set to the first mode configuration, which can be a predetermined mode configuration used to start the method or evaluation step, respectively. In the next step, the metering pump is operated in the drive mode set to the first mode configuration. During this operation, a stroke diagram is detected. The stroke diagram shows the force and / or pressure generated by the metering pump during the stroke length or pump cycle, or the force and / or pressure applied to the fluid. The stroke diagram can detect the pressure of the pumped fluid, such as the pressure of the pumped fluid inside the pump chamber. Rather than directly detecting the pressure, the force acting on the pump driver or the displacement element inside the metering pump can be detected. Furthermore, any other suitable value representing force and / or pressure can be detected or derived, for example, by suitable sensors. For example, an electric value of an electric drive can be detected, which represents the torque generated by the drive. Knowing the geometry of the drive, the force acting on the displacement element and the pressure applied to the fluid can be calculated, i.e., there is a known relationship between these values and the pressure or force. Therefore, instead of considering forces or pressures in a stroke diagram, it is also possible to consider torques or electrical values representing torques in such a stroke diagram. All of these possibilities are encompassed by the definition "stroke diagram" used hereinafter.

[0006] In the next step, at least one criterion, namely the first criterion in the first evaluation step, is derived from at least a portion of the detected stroke diagram. For example, the position of a characteristic point in the diagram can be considered, and the stroke length and / or force at that characteristic point in the diagram can be detected. Furthermore, a portion of the diagram and the force or pressure curve within that portion can be considered as characteristic criteria. In the next step, a decision matrix or decision tree is used to decide how to proceed with the evaluation procedure. This means that the next step in the evaluation procedure is decided based on the derived (first) criterion (i.e., by comparing this criterion with a predetermined value or characteristic). Based on the result of this evaluation or comparison, a decision is made as to which step should be the next or subsequent evaluation step. Based on this decision, in the next evaluation step, the drive mode is set to a second or another mode configuration corresponding to the selected evaluation step, and the steps are then repeated, i.e., the metering pump is operated in the drive mode with the second or another configuration, and then a criterion is again derived from the detected stroke diagram. The next decision on how to proceed is then made in the decision matrix. This procedure can be repeated for several steps. In particular, each evaluation step can be used to further clarify a certain error in the installation, or to evaluate different aspects of the installation or possible errors, such as, for example, cavitation, too high or too low pressure on the outlet side of the pump, etc.

[0007] The key part of this method is to use a decision matrix with different evaluation steps and decide at each step what the next evaluation step should be. These decisions can be between two or more alternative evaluation steps. In particular, these decisions involve comparing a criterion with a predetermined characteristic or characteristic value (e.g., a threshold value). For example, if the criterion is above a predetermined threshold, then the first possible evaluation step will follow, while if the criterion is below the threshold, then the second alternative evaluation step will follow.

[0008] In particular, the method according to the present invention is configured for use with a metering pump as a positive displacement pump, which preferably has a reciprocating displacement element. The reciprocating displacement element is preferably driven by an eccentric drive mechanism, which is driven by an electric drive motor (preferably a stepper motor). In such a drive mechanism, the movement is recorded, for example, by an angle sensor or based on an electrical value from the drive motor. Alternatively, any other suitable position sensor can be provided in the drive device to detect the position of the displacement element, in particular the linear position of the displacement element. For example, the displacement element can be a plunger or a membrane that moves in a reciprocating manner.

[0009] According to another embodiment, when repeating the step of deriving at least one criterion from at least a portion of the detected stroke profile, a second and / or further criterion is derived or taken into account. This means that different criteria can be derived and taken into account in different evaluation steps in the decision matrix. This can be used to further clarify a possible error or to evaluate different possible errors in the installation.

[0010] As described above, a drive mode defines the movement of the actuator during a pump cycle, such as a single reciprocating movement of a reciprocating displacement element. For example, a drive mode can define the speed, speed variation, and / or stopping of a metering pump. Preferably, the drive mode defines the speed, speed variation, and / or stopping of the metering pump along at least one stroke or cycle of the metering pump. Furthermore, a drive mode can define a number of pump cycles or strokes. For example, the speed can vary during several cycles or strokes of the metering pump. All of these different operating conditions or configurations are set in a mode configuration, as described above.

[0011] After setting the drive mode to the first mode configuration or another mode configuration, in the next step, the metering pump is preferably operated for a predetermined amount of time, a predetermined number of strokes, or a predetermined stroke length. Depending on the criterion to be analyzed, the duration of operation, number of strokes, or stroke length can be set for the corresponding evaluation step. For example, the criterion can be a point in the stroke graph or a deviation of the curve in the graph. This requires operating for a certain time to detect the deviation. Furthermore, operating for several strokes or a longer duration can provide a more accurate evaluation.

[0012] At least one final evaluation step can include an output, an intermediate result, or a final result, and / or a predetermined action of the metering pump can be initiated during the final evaluation step. For example, the result can be a correct installation, or it can indicate a detected error. Furthermore, the evaluation result can be a setting for further operation of the pump, such as a maximum drive speed, for example, during a pressure stroke or a suction stroke.

[0013] Preferably, the at least one criterion mentioned above is at least one force or pressure value and / or a force or pressure curve in at least a portion of the stroke diagram. In the meaning of the present invention, a force or pressure value can be a value representing the force or pressure or a value derived from the detected force or pressure. Furthermore, it can be a value representing a parameter that is proportional to the force or pressure value. For example, this can be the torque of the drive motor or an electrical value representing such a torque. For example, the criterion can be that the force or pressure occurs at a certain point or portion of the stroke. Furthermore, the entire curve can be considered in a certain portion of the pump cycle or stroke.

[0014] For example, at least a portion of the stroke diagram may represent at least one segment of the suction stroke and / or pressure stroke. This may be a characteristic point or segment of the suction stroke and / or pressure stroke. For example, for this portion, the pressure or force value may be considered as a standard as discussed previously.

[0015] According to another possible embodiment, at least one criterion defines the stroke position in the stroke diagram, preferably the position where the force changes significantly, for example, the position where the pressure build-up begins. Thus, the criterion can define characteristic parts or characteristic points in the stroke diagram, in particular the points where the stroke direction changes, for example, between the suction stroke and the pressure stroke, or the points where the pressure changes substantially, for example, when the pressure build-up begins after the suction stroke, i.e., at the beginning of the pressure stroke. The pressure or force detected at these characteristic points can indicate certain faults or installation problems. Additionally or alternatively, the position of the characteristic points along the stroke length can indicate a fault or incorrect installation.

[0016] Furthermore, the drive mode in its drive mode configuration may include a stop at a predetermined position in the stroke. In this case, the criterion derived may be a pressure change detected after the stop. For example, a pressure loss after a stop in a pressure stroke may indicate a leak in the pump chamber, the diaphragm, and / or one of the valves, for example.

[0017] Preferably, the predetermined positions are positions during the pressure stroke, positions during the suction stroke, or positions at the transition between the suction stroke and the pressure stroke, or between the pressure stroke and the suction stroke. These are examples of characteristic points or portions in the stroke diagram. Under proper operation, these characteristic points or portions have predetermined shapes or predetermined positions. Deviations from the predetermined positions or from predetermined pressure or force ranges at the corresponding positions may indicate improper installation or a malfunction.

[0018] According to another possible embodiment, the criterion derived is that the change in pressure or force exceeds a predetermined threshold. The threshold may be a predetermined minimum or maximum value. For example, excessive pressure in the pump chamber may indicate that a valve or outlet line is closed. On the other hand, excessively low pressure may indicate, for example, that the suction line or suction valve is closed, or that the suction line is too long.

[0019] One possible installation issue that this method can detect or assess is whether there is sufficient back pressure in the metering pump's outlet line. To assess whether the metering pump has sufficient back pressure, at the beginning of the assessment step, the drive mode is set to a first mode configuration including a first drive speed. Therefore, the pump, particularly a displacement element such as a plunger or diaphragm, moves at the first drive speed. At this first drive speed, at least one criterion for detection and analysis can be the maximum force or pressure achievable during the pressure stroke. If the detected maximum pressure or force is below a predetermined threshold (i.e., a minimum value), then in a subsequent step, the drive mode is set to a second mode configuration including a higher second drive speed. Therefore, the second drive speed included in the second mode configuration is higher than the first drive speed in the previously used first mode configuration. Next, the pump is operated in the second mode configuration (i.e., at the higher second drive speed). During this operation, at least one criterion is again tested, namely, the maximum force or pressure achieved during the pressure stroke. If this detected maximum force or pressure is still below the predetermined threshold, a predetermined final assessment step has been reached. In this final assessment step, a result indicating insufficient back pressure in the metering pump can be output to the user or operator. If increasing the speed does not increase the pressure above the desired minimum pressure, this indicates that the back pressure on the outlet side of the metering pump is too low. This indicates that the pump is not properly installed and should be changed before operation. The assessment of whether sufficient back pressure exists can be performed in more than two evaluation steps, i.e., the speed can be increased in several steps before reaching the final evaluation step.

[0020] Another problem that this method can detect can be cavitation. In order to assess cavitation according to this method, preferably, the drive mode is set to the first mode configuration including the first driving speed. Next, the pump operates with this first driving speed and detects the stroke position at which pressure is established in the stroke diagram as at least one criterion. The detected position is compared with a predetermined stroke length, which defines the threshold value of the position at which pressure should be established. If the actual position at which pressure is established is detected to be higher than the predetermined stroke length, cavitation is present in the dosing head or the pump chamber, respectively. In order to further assess in the following assessment step, the speed mode is set to the second mode configuration including a lower second driving speed (i.e., a driving speed lower than the first driving speed used in the previous assessment step). Next, the pump operates with this lower second driving speed and detects the stroke position at which pressure is established in the stroke diagram as at least one criterion. If the stroke position is lower than the predetermined stroke length, i.e., lower than the predetermined threshold value, the maximum driving speed that avoids harmful cavitation has been found, and the final assessment step has been reached. It may take more than two assessment steps to find the maximum driving speed that allows operation without harmful cavitation. This may require reducing the drive speed in different mode configurations for different evaluation steps in more than two evaluation steps. In addition, this may require a certain degree of increase in the drive speed, reducing the step size of the speed change to more accurately assess the maximum possible drive speed without harmful cavitation. If the minimum drive speed has been reached and the stroke position at which the pressure builds up is still higher than the predetermined stroke length, that is, the predetermined minimum stroke length, the final evaluation step has been reached, indicating that operation without harmful cavitation cannot be performed. This can be output to the operator so that the operator can change the installation to avoid cavitation. For example, a suction line with a larger cross-section or a shorter suction line can be used to reduce cavitation.

[0021] In addition to the aforementioned method, a metering pump is also a subject of the present invention. Preferred embodiments of such a metering pump or metering pump system are described below. However, the preferred embodiments of the method discussed above should also be considered preferred embodiments of the metering pump system or metering pump device. Furthermore, the details and method steps described below with reference to the metering pump device or system should be considered preferred embodiments of the aforementioned method.

[0022] The metering pump device according to the present invention includes at least one movable displacement element, such as a plunger or a diaphragm. In addition, the metering pump device includes an electric drive that moves the displacement element (preferably in a reciprocating manner). The electric drive can be an electric motor, such as a brushless DC motor or a stepper motor, which drives the displacement element through a suitable gear or transmission system (e.g., an eccentric drive). Alternatively, the electric drive can be a linear drive or a magnetic drive. In addition, the metering pump device includes at least one electronic control device that is configured to control the metering pump device and its electric drive. The at least one electronic control device includes an installation assessment module that is configured to enable it to perform the above method. For example, the installation assessment module can be a software module inside the electronic control device. The installation assessment module can be configured to start an installation assessment program after the pump device is set or, for example, according to the operator's requirements. Preferably, the installation assessment module is configured to automatically perform several assessment steps based on a decision matrix, assess different possible faults or installation problems, and ultimately set controls to avoid faults and / or output instructions to the operator, informing the operator which changes need to be made to the installation or which parts of the installation should be manually checked.

[0023] According to another possible embodiment, the metering pump device includes at least one sensor device that is connected to and / or integrated into an electronic control device. Preferably, the at least one sensor device is configured to detect force or pressure (preferably, force or pressure acting on a displacement element) and / or the position of the displacement element. For example, the sensor device can be a pressure sensor that detects the pressure inside a pump chamber, the volume of which is alternatingly reduced and increased by the movement of the displacement element. The pressure sensor can be integrated into the pump device so that it is internally connected to the electronic control device. However, in alternative embodiments, an external connection, such as a wired connection, can also be adopted. In addition, other sensor devices, such as position sensors or angle sensors, can be arranged inside the metering pump device, particularly inside the driver of the metering pump device. In addition, the configuration of the electronic control device that monitors the appropriate electrical value of the electric drive motor can be considered as a sensor device. All of these sensor devices can be internally connected to the electronic control device, or, for example, in the case where the electronic control device is an external electronic control device connected to the electric drive (e.g., via a cable or wireless connection), can have an external connection to the electronic control device. In other possible embodiments, one or more sensor devices can be external sensors connected to the metering pump device. For example, these external sensors can be pressure sensors arranged inside an installation connected to a metering pump. These sensors can be considered as part of the metering pump device, or as part of a metering pump system comprising at least one metering pump device and at least one sensor device. A metering pump system can include a central electronic control unit that controls several metering pump devices. In this case, the installation assessment module can be a central control module that assesses the different metering pump devices in the system.

[0024] Preferably, the installation assessment module is a software module executed by an electronic control unit that is part of a pump unit including an electric drive and a displacement element. Alternatively, the installation assessment module may be executed by a control unit that is remotely located from the pump unit and connected to the pump unit via a communication link. Thus, the installation assessment module may be implemented in an electronic control unit that is remotely located from the metering pump device, for example as a cloud computing system connected to one or more metering pump devices via a communication link or network (e.g., the Internet). BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention will be described below by way of example with reference to the accompanying drawings, in which:

[0026] Figure 1 A metering pump arrangement is shown schematically.

[0027] Figure 2is a flow chart schematically illustrating the method according to the present invention.

[0028] Figure 3 is a flow chart schematically illustrating a decision matrix used in the present invention.

[0029] Figure 4 Detecting missing back pressure by using a stroke diagram is schematically illustrated.

[0030] Figure 5 Detection of unwanted cavitation by using a stroke diagram is schematically illustrated.

[0031] Figure 6 Detecting leakage of a suction valve by using a stroke diagram is schematically illustrated.

[0032] Figure 7 The pressure test in the stroke diagram is shown schematically to further clarify the installation problem. DETAILED DESCRIPTION

[0033] The method according to the present invention is configured as described in reference Figure 1 Basically explained for use with the metering pump device or metering pump installation equipment. Figure 1 Shown are metering pump devices 2 comprising a driver 4, each having a pump head or metering head 6. A pump chamber 8 is located inside the metering head 6, the volume of which is variable by the movement of a diaphragm 10. The diaphragm 10 is moved by the driver 4. For example, the diaphragm 10 moves via a rod, which is connected to a rotatable electric drive motor of the rod via a linear drive, a magnetic drive, or an eccentric drive mechanism and moves in a reciprocating manner. For example, the electric drive motor can be a stepping motor. The metering head 6 comprises an inlet valve or suction valve 12 and a pressure valve or outlet valve 14. The inlet valve 12 is connected to a suction line 16, for example, which extends into a liquid container 18. The outlet valve 14 is connected to a pressure line 20, which extends toward or is connected to a facility to which the metering pump device 2 supplies liquid. Through the movement of the diaphragm 10, liquid is sucked out of the liquid container 18 and pumped into the pressure line 20. By adjusting the speed and / or stroke length of the diaphragm 10, the amount of liquid per unit time can be changed.

[0034] The metering pump device 2 also includes an electronic control device 22, which is configured to control the driver. In particular, the electronic control device 22 can adjust the speed and / or stroke length of the movement of the diaphragm 10. The electronic control device 22 may include a suitable microprocessor, a storage device and other required electronic components. In particular, the control device is configured to execute at least one control program. The metering pump device 2 includes a sensor device, which is connected to the control device 22 and provides sensor information for controlling and monitoring the operation of the metering pump device 2. In this example, a pressure sensor 23 is provided at the pump chamber 8, which detects the liquid pressure inside the pump chamber 8. The driver 4 is configured to detect and record the stroke position of the diaphragm 10. The control device 22 is configured to detect a pressure-stroke diagram or a force-stroke diagram based on the detected stroke position and the pressure value detected by the pressure sensor 23.

[0035] Furthermore, the electronic control device 22 may include a communication link 24 configured for communicating with external components and a control device, such as a mobile device 26 (e.g., a mobile computer, smartphone, or tablet), or with the internet, including a cloud computing device 28. Via the communication link 24, the metering pump device 2 can be at least partially controlled by an external control device, or a desired configuration for the control device 22 can be received. Furthermore, the communication link 24 can be used to output information from the electronic control device 22 to an external control system and / or an operator. Additionally, or alternatively, the control device 22 can include a display 30 for outputting information to an operator. Furthermore, the control device 22 can include an input device 32 for configuring the control device 22.

[0036] The control device 22 or an external control system that may be implemented as a cloud computing device 28 includes an installation assessment module that is configured to execute a method for assessing proper installation of the metering pump. For example, proper installation may include assessing one or more of the following issues or faults:

[0037] - The back pressure in pressure line 20 is too low, the pressure retaining valve is faulty, or pressure line 20 is not connected

[0038] - Back pressure is too high, pressure line 20 is closed

[0039] -Pressure is too low, small indicator diagram (stroke diagram)

[0040] - There is air in the metering head 6 or pump chamber 8

[0041] - Harmless cavitation, such as poor suction line dimensions

[0042] - Harmful cavitation, e.g. suction line 16 closed

[0043] - Increased cavitation (e.g. wrong size of suction line 16)

[0044] - pulsations, e.g. due to the lack of a pulsation dampener

[0045] - pressure loss during the suction or discharge stroke, e.g. due to leakage in the valve or pump chamber 8

[0046] The installation assessment program according to the method of the present invention can be started after the pump is installed, can be manually started by the operator, or can be automatically started. In addition, the program can be executed from time to time to check for certain faults of the installation and / or monitor the operation of the metering pump device.

[0047] like Figure 2 As shown in the principle, after the program starts S, in the evaluation step E n In the embodiment of the present invention, i.e. at the start of the first evaluation step E1 with the first predetermined mode configuration PC1, the pump is operated. Therefore, the drive mode of the metering pump device 2 is set to the first mode configuration PC1, in particular the first mode configuration PC1 with the first predetermined drive speed, based on which the drive 4 is operated under the control of the electronic control device 22. During this operation, a stroke diagram 34 is recorded. In the stroke diagram 34, the pressure in the pump chamber 8 detected by the pressure sensor 23 or a related value as, for example, a force or torque acting in the drive 4 is recorded in relation to the stroke length or the stroke position of the linear movement of the diaphragm 10. The stroke diagram 34 shows the force or pressure p on the ordinate and the stroke length or the stroke position s on the abscissa. The detected stroke diagram 34 is evaluated by deriving from it and taking into account at least one first criterion. This is done in the analysis step A. n The decision matrix 36 is used for different evaluation steps E. n Define the corresponding analysis step A n , and define for analysis step A n Different results for R n The next evaluation step E n+1 Depending on the corresponding option in the decision matrix 36, from the analysis step A n The result R n The result R n It can be an intermediate result or a final result. In the case of a final result, the evaluation procedure reaches a final step F, which can be, for example, stopping the operation if the detected fault does not allow normal operation, or normal operation if a suitable setting can be found in the installation evaluation procedure. Depending on the decision matrix 36, the intermediate result R n Further evaluation steps may be required E n+1 To this end, before starting the next evaluation step E n+1 Before, the next evaluation step En+1 Changing the drive mode to the second or another mode configures the PC n+1 Therefore, after a branch in the decision matrix 36, several evaluation steps E are performed. n and its corresponding analysis step A n to detect and identify different installation problems.

[0048] Figure 3 An example of a decision matrix 36 is given in . Figure 3 The example in FIG is a decision matrix 36 for detecting and analyzing cavitation. After the start S, in a first evaluation step E1, the drive 4 is operated at a medium speed (e.g., 50% of the maximum speed). During this operation, for a predetermined duration or a predetermined number of strokes, the stroke diagram 34 is detected and analyzed in an analysis step A1. If an overpressure is detected, the pump is immediately stopped as a final result F1. If an excessively high pressure or cavitation is detected in the analysis A1, the intermediate result R is then 1a In the evaluation step E2, the drive mode is set to a second mode configuration PC2 with a further reduced speed (e.g., a speed of 25%). In the following evaluation step E2, the pump device is operated at this further reduced speed (i.e., the drive mode with the second mode configuration PC2). If overpressure is detected in step E2, the operation is stopped as a final result F2. If cavitation or high pressure is detected as a result R in the analysis step of the evaluation step E2, 2a , then a third evaluation step E3 with a third mode configuration PC3 follows for further detailed analysis. In this analysis, the actuator 4 moves to a predetermined stroke position in the suction stroke. At this position, the actuator 4 stops and the pressure p is monitored. If the pressure drops, this may indicate a dimension error of the suction line 16, which can be output as a result R, for example. 3a If the pressure is stable, this may indicate that the suction line 16 is closed, which can be output as result R 3b , then, the result R 3b This can be the final result F or the end of the evaluation procedure. If no cavitation is detected in the evaluation step E2, then in this example, at the result R 2b There are no further evaluation steps and the control device 22 sets the metering pump device 2 to mode O for normal operation.

[0049] If no cavitation is detected in the first evaluation step E1, this is a second possible outcome R of the first evaluation step. 1bThen, in a subsequent step, the drive mode is set to a mode configuration PC corresponding to normal operation. During this normal operation, the pressure-stroke diagram 34 can be derived and monitored. If cavitation is detected in the monitoring step M, the control device 22 can reduce the drive speed and initiate an evaluation procedure, for example, the evaluation step E1. If no cavitation is detected, normal operating mode O is continued.

[0050] Figure 3 Only an example of a decision matrix 36 is shown. In practice, the decision matrix 36 may have many more evaluation steps and / or branches, i.e., the decision matrix 36 is more complex to analyze different installation problems and / or faults. Figures 4 to 7 Further examples of possible evaluation steps that may be part of such a decision matrix 36 are explained.

[0051] Figure 4 An example of detecting whether there is sufficient back pressure in the pressure line 20 is shown. In a first evaluation step, the actuator 4 is operated at a first speed (i.e., a first mode configuration), for example, with a medium drive speed. In this example, the portion 38 of the curve in the stroke diagram representing the pressure stroke is below a predetermined minimum pressure P min Instead of pressure, the force or torque acting on the driver 4 can be considered. The force will then be below the minimum force. For a second evaluation step, the drive mode is set to the second mode configuration PC2 and the pump device is operated again for a few strokes. In this second evaluation step, the pump is operated at a higher speed (preferably the maximum speed). If in this second evaluation step, at the higher speed, the pressure or force of the portion 38 of the stroke diagram is still below the predetermined minimum pressure P min , then this indicates a lack of back pressure, for example due to a defective pressure retaining valve in the pressure line 20. If at higher speeds, the portion 38 is above a predetermined minimum pressure P min , then this indicates that the back pressure is sufficient so that a correct pressure build-up can be achieved at a higher pressure. Then, as a result, the metering pump device 2 can continue normal operation, or further evaluation steps can be performed to detect different faults before commencing normal operation.

[0052] Figure 5The example in Figure 1 illustrates the possibility of detecting harmful cavitation. In order to evaluate cavitation in a first evaluation step, the drive mode is set to a first mode configuration with a medium speed and the driver 4 is operated for several strokes. The stroke diagram or pressure stroke diagram 34 detected in the case of cavitation respectively shows that no pressure buildup begins directly at the end 42 of the intake stroke (i.e., at the left end of the diagram). In this case, the pressure buildup begins after the stroke length l1 of the pressure stroke. In addition, in the case of cavitation, a negative pressure occurs during the intake stroke 40. For the subsequent second evaluation step, the drive mode is changed to a second mode configuration PC2 with a reduced speed at least during the intake stroke 40. It is then analyzed in the stroke diagram 34 whether cavitation is still present. Figure 5 The lower left figure in shows that the stroke length l2 is reduced compared to the stroke length l1 in the first evaluation step. Therefore, cavitation is reduced. However, cavitation still occurs, and the pressure buildup does not start directly, but after the stroke length l2 in the pressure stroke. In the next evaluation step, the speed during the suction stroke can be further reduced to evaluate whether an suction speed can be found at which cavitation does not occur, and whether this suction speed is acceptable for operation. An alternative result in a second or further evaluation step could be that cavitation no longer occurs. This is in Figure 5 In this case, the pressure build-up begins directly at the end point 42 of the suction stroke.

[0053] Figure 6 An example for evaluating a possible leak in the suction valve 12 is shown. In a first evaluation step, the pump is started in a drive mode according to a first mode configuration with a medium speed. Figure 6 As can be seen in the force-pressure diagram 34 in the upper center, the portion 38 of the curve representing the pressure stroke decreases towards the end 44 of the pressure stroke. This may indicate a leak. In a subsequent evaluation step, this possible leak can be further analyzed. For example, in a subsequent evaluation step, the pressure stroke can be stopped at point 46, as shown in FIG. Figure 6 If the pressure detected by the pressure sensor 23 drops after this stop, this indicates that there is a leak in the pump chamber or the suction valve 12. By increasing the speed, the pressure loss can be reduced or moved towards the end point 44 of the pressure stroke 38, as shown in the figure below. Figure 6 Thus, according to the method, not only can a fault be detected, but also a setting can be found which at least partially compensates for the installation problem, for example by increasing the speed in the pressure stroke 38 or reducing the speed in the suction stroke 40 (to avoid cavitation).

[0054] Figure 7Another example of a force-stroke diagram 34 is shown, which includes examples for further evaluating certain installation issues. For detailed analysis, for example, the stroke can be stopped at certain points 46, 48, 52, or 54 for further analysis. For example, as previously described with reference to Figure 6 As explained, the driver 4 can be stopped at point 46 approximately midway through the pressure stroke 38. This allows leaks to be detected, as described with reference to FIG. Figure 6 Furthermore, pulsation can be detected, e.g. Figure 7 Schematically shown. Another possibility is to stop the suction stroke, for example, at point 54 approximately in the middle of the suction stroke 40. At this point, a leak in the pressure valve 14 can be detected. If the pressure rises, this indicates that there is a leak in the pressure valve 14. Stopping at point 48 at the beginning of the pressure stroke will allow, for example, to detect an excessive suction height of the suction line 16 when there is still a negative pressure at the beginning of the pressure stroke. In addition, starting from the stop at 54 in the middle of the suction stroke 40, the time until the pressure balances can be detected, which can indicate friction and / or inertia, allowing the cause of cavitation to be further clarified.

[0055] Reference Signs List

[0056] 2 Metering pump device

[0057] 4 Drivers

[0058] 6 Dosing head

[0059] 8 Pump chamber

[0060] 10 diaphragm

[0061] 12 Inlet valve

[0062] 14 Outlet valve

[0063] 16 Suction line

[0064] 18 Liquid Containers

[0065] 20 Pressure Line

[0066] 22 Electronic Control Unit

[0067] 23 Pressure sensor

[0068] 24 Communication Links

[0069] 26 mobile devices

[0070] 28 Internet / cloud computing devices

[0071] 30 Display

[0072] 32 Input devices

[0073] 34 Stroke diagram, pressure stroke diagram

[0074] 36 Decision Matrix

[0075] 38 The portion of the curve representing the pressure stroke

[0076] 40 The portion of the curve representing the suction stroke

[0077] 42 End of the suction stroke

[0078] 44 End of pressure stroke

[0079] 46 Points during the pressure stroke

[0080] Points 48, 52, and 54 in the force-stroke diagram

[0081] E n Evaluation Steps

[0082] A n Analysis steps

[0083] R n result

[0084] PC n Mode Configuration

Claims

1. A method for assessing the proper installation of a metering pump (2), characterized by the following steps: a) Set the drive mode to the first mode configuration (PC n ), b) operating the metering pump (2) in the drive mode, c) detecting a stroke diagram (34) during operation of the metering pump (2) in the drive mode, the stroke diagram representing the relationship between force and stroke position, d) deriving at least one first criterion from at least a portion (38, 40) of the detected stroke diagram (34), e) Based on the derived criteria, the next evaluation step is selected by using the decision matrix (36) (E n ), f) According to the selected evaluation step (E n+1 ) sets the drive mode to the second mode configuration or another mode configuration (PC n+1 ),as well as Steps b) to f) are repeated until at least one predetermined final evaluation step (F) in the decision matrix (36) is reached.

2. The method according to claim 1, characterized in that The metering pump is a positive displacement pump, preferably having a reciprocating displacement element (10).

3. The method according to claim 1 or 2, characterized in that When step d) is repeated, a second criterion and / or a further criterion is derived.

4. The method according to claim 1, wherein The drive mode defines a speed, a speed change and / or a stop of the metering pump, preferably a speed, a speed change and / or a stop of the metering pump along at least one stroke of the metering pump.

5. The method according to one of the preceding claims, characterized in that In step b), the metering pump (2) is operated for a predetermined amount of time, a predetermined number of strokes or a predetermined stroke length.

6. The method according to one of the preceding claims, characterized in that In at least one final evaluation step (F), an intermediate result (R n ) or the final result, and / or start the predetermined action of the metering pump (2).

7. The method according to one of the preceding claims, characterized in that The at least one criterion is at least one force or pressure value and / or a force or pressure curve in at least a portion of the stroke diagram (34).

8. The method according to one of the preceding claims, characterized in that The at least one portion (38, 40) of the stroke diagram (34) represents at least one segment of an intake stroke and / or a pressure stroke.

9. The method according to one of the preceding claims, characterized in that The at least one criterion defines a stroke position (46, 48, 50, 52, 54) in the stroke diagram, preferably a position where force changes significantly, such as where pressure buildup begins.

10. The method according to one of the preceding claims, characterized in that The drive pattern includes a stop at a predetermined position (46, 50, 54) of the stroke, and the derived criterion is a pressure change detected after the stop.

11. The method according to claim 10, characterized in that The predetermined position is a position in a pressure stroke (38), a position in a suction stroke (40), or a position at a transition between the suction stroke (40) and the pressure stroke (38) or between the pressure stroke (38) and the suction stroke.

12. The method according to claim 10 or 11, characterized in that The resulting criterion is that the pressure change exceeds a predetermined threshold.

13. The method according to one of the preceding claims, characterized in that To assess whether the metering pump (2) has sufficient back pressure: setting the drive mode to a first mode configuration (PC1) comprising a first drive speed, In step d), the at least one criterion comprises the maximum force or pressure reached, In step e), if it is detected that the maximum force or pressure reached is lower than a predetermined threshold value (P min ), then in step f), the drive mode is set to a second mode configuration (PC2) comprising a higher second drive speed, and After repeating steps b) to d), if the maximum force or pressure reached is still below the predetermined threshold value (P min ), then the predetermined final evaluation step (F) has been reached.

14. The method according to one of the preceding claims, characterized in that To assess cavitation: setting the drive mode to a first mode configuration (PC1) comprising a first drive speed, In step d), the at least one criterion comprises the stroke position (l1) at which the pressure build-up begins, In step e), if it is detected that the position is above a predetermined stroke length, then in step f), the speed mode is set to a second mode configuration (PC2) comprising a lower second drive speed, and After repeating steps b) to d), the maximum drive speed for avoiding harmful cavitation is found as a final evaluation step (F) if the stroke position is below the predetermined stroke length, or the final evaluation step (F) has been reached if the minimum drive speed has been reached and the detected stroke position is still above the predetermined stroke length.

15. A metering pump device (2) comprising at least one movable displacement element (10), an electric drive (4) for moving the displacement element (10), and at least one electronic control device (22) configured to control the metering pump device (2) and its electric drive (4), characterized in that The at least one electronic control device (22) comprises an installation assessment module which is configured such that it performs the method according to one of claims 1 to 14.

16. The metering pump device (2) according to claim 15, characterized in that At least one sensor device (23) is connected to the electronic control device (22) and / or is integrated into the electronic control device (22), preferably, the at least one sensor device (23) is configured to detect a force or pressure, preferably a force or pressure acting on the displacement element (10), and / or to detect the position of the displacement element (10).

17. The metering pump device (2) according to claim 15 or 16, characterized in that The installation assessment module is a software module executed by an electronic control device (22), which is part of a pump unit (2) comprising the electric drive (4) and the displacement element (10), or the installation assessment module is a software module executed by a control device (28), which is arranged remote from the pump unit (2) and is connected to the pump unit (2) via a communication link (24).

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