Intelligent safety control method and device for hydraulic press

Abstract

The invention discloses an intelligent safety control method and device for a hydraulic press, and particularly relates to the technical field of hydraulic press control. When external state data of the hydraulic press is not abnormal, the hydraulic press is started to detect all parts, and the instantaneous pressure of the hydraulic press is compared with a preset instantaneous pressure threshold value; if yes, a water drain valve and a vent valve are opened for pressure reduction, and whether the hydraulic press needs to be controlled to be forcibly shut down or not is judged; if not, dynamically adjusting the opening and closing of the valve according to the pressure change, maintaining the pressure when the pressure reaches a proper numerical value, obtaining a real-time change curve of the pressure within a preset pressure maintaining time, comparing the real-time change curve with a preset standard curve, and judging whether the detected part has defects or not; therefore, when defect detection is carried out on the hydraulic press part, the defect detection can be carried out on the hydraulic press part after proper detection conditions are ensured, and corresponding control measures are taken, so that the safety of the hydraulic press is ensured, and the operation risk of the hydraulic press is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of hydraulic press control, and in particular to an intelligent safety control method and device for a hydraulic press. Background Art

[0002] A hydraulic press is a type of hydraulic press that uses water pressure to shape or process materials. It is widely used in manufacturing, metal processing, plastic molding, and other fields. By adjusting the water pressure, it can achieve precise shaping, pressing, and cutting of various materials, thereby improving production efficiency and product quality. This type of hydraulic press can not only effectively save energy, but also reduce environmental pollution during the production process.

[0003] When a hydraulic press is in use, it generally involves a variety of parts, such as box parts, disc parts, etc. The coordination of multiple parts ensures that the hydraulic press can work normally and safely, thereby improving production efficiency and product quality.

[0004] However, when performing defect detection on hydraulic press parts, if the appropriate detection conditions cannot be ensured and the hydraulic press parts are directly inspected for defects, it may pose a threat to the safety of the hydraulic press and increase the risk of hydraulic press operation. Summary of the invention

[0005] The purpose of the present invention is to solve the problem and to propose an intelligent safety control method and device for a hydraulic press.

[0006] In a first aspect of the present invention, an intelligent safety control method for a hydraulic press is first proposed, the method comprising:

[0007] Monitor the external state data of the hydraulic press in real time and make judgments; if there is no abnormality in the external state data of the hydraulic press, start the hydraulic press to detect each part; the external state data includes whether the parts are installed in place, whether the air pressure is normal, and whether the parts are clamped;

[0008] When the hydraulic press is turned on to inspect each part, the instantaneous pressure of the hydraulic press is monitored and compared with the preset instantaneous pressure threshold;

[0009] When the instantaneous pressure is greater than the preset instantaneous pressure threshold, the water drain valve and the air drain valve are opened to reduce the pressure, and the pressure drop rate within the preset time, the pressure value after it drops to the normal value, and the load of the hydraulic press during the drop determine whether the hydraulic press needs to be forced to stop;

[0010] When the instantaneous pressure is not greater than the preset instantaneous pressure threshold, the valve switch is dynamically adjusted according to the pressure change. When the pressure reaches the normal value, the pressure is maintained, and the real-time pressure change curve within the preset pressure holding time is obtained and compared with the preset standard curve to determine whether the inspected parts have defects.

[0011] Optionally, real-time monitoring of external status data of the hydraulic press and determination include:

[0012] When the inspection parts are installed in place, the air pressure is normal and the parts are clamped, it is judged that the external state data of the hydraulic press is normal, and the hydraulic press is turned on to inspect the parts; if not, it is judged that the external state data of the hydraulic press is abnormal, the hydraulic press is not turned on to inspect the parts, and the first alarm is issued.

[0013] Optionally, comparing the instantaneous pressure with a preset instantaneous pressure threshold comprises:

[0014] If the instantaneous pressure is equal to the preset instantaneous pressure threshold, the water drain valve and the air drain valve are opened to reduce the pressure, and whether the pressure drops to the normal value within the preset time is recorded. If the pressure does not drop to the normal value within the preset time, the hydraulic press will enter the forced shutdown state and issue a second alarm;

[0015] When the pressure drops to a normal value within a preset time, it is determined whether the hydraulic press needs to be forced to stop based on the pressure drop rate within the preset time, the pressure value after dropping to the normal value, and the load of the hydraulic press during the drop.

[0016] Optionally, judging whether it is necessary to control the hydraulic press to be forced to stop according to the pressure drop rate within a preset time, the pressure value after the pressure drops to a normal value, and the load of the hydraulic press during the drop includes:

[0017] The preset time is divided into several sub-time periods, the pressure drop rate in each sub-time period is obtained, and the pressure drop rate abnormality coefficient is calculated according to the preset pressure drop rate in each time period. The calculation formula is: Where PL is the pressure drop rate anomaly coefficient, Gf c is the actual pressure drop rate corresponding to the cth time period, Gt c The standard pressure drop rate preset for the cth sub-time period, ω c is the preset weight value of the pressure drop rate in the cth sub-time period, n is the total number of sub-time periods, and n is a positive integer;

[0018] Whether the hydraulic press needs to be forced to stop is determined based on the abnormal coefficient of the pressure drop rate, the pressure value after it drops to the normal value, and the load of the hydraulic press during the drop.

[0019] Optionally, judging whether it is necessary to control the hydraulic press to forcibly stop according to the abnormal coefficient of the pressure drop rate, the pressure value after dropping to a normal value, and the load of the hydraulic press during the drop includes:

[0020] When the pressure drops to a normal value within a preset time, the pressure values ​​at multiple times in a subsequent preset stable time period are obtained, and the pressure values ​​at multiple times are compared with the normal values. When the pressure value and the normal value are greater than the normal value, the corresponding pressure value is marked as an abnormal pressure value;

[0021] The total number of abnormal pressure values ​​is divided by the total number of pressure values ​​in the preset stable time period to obtain the pressure value deviation coefficient;

[0022] Calculate the standard deviation of the pressure values ​​at multiple moments in the preset stable time period, and divide the standard deviation by the preset standard deviation threshold to obtain the pressure value fluctuation coefficient;

[0023] The pressure value deviation coefficient and the pressure value fluctuation coefficient are normalized to obtain the unqualified coefficient of the pressure value after the decrease, and whether the hydraulic press needs to be controlled to be forced to stop is determined based on the pressure decrease rate abnormality coefficient, the unqualified coefficient of the pressure value and the load of the hydraulic press during the decrease.

[0024] Optionally, judging whether it is necessary to control the hydraulic press to be forced to stop according to the abnormal coefficient of the pressure drop rate, the unqualified coefficient of the pressure value and the load of the hydraulic press during the drop includes:

[0025] Obtaining the actual load value of the hydraulic press at multiple moments within the preset time of pressure drop, and dividing the actual load by the rated load value to obtain the load factor at the corresponding moment;

[0026] Record the load factor at all times, obtain the maximum load factor, and divide the maximum load factor by the preset maximum load value of the hydraulic press under normal reduced pressure to obtain the equipment load factor;

[0027] Determine whether the hydraulic press needs to be forced to shut down based on the pressure drop rate abnormality coefficient, pressure value unqualified coefficient and equipment load coefficient.

[0028] Optionally, judging whether it is necessary to control the hydraulic press to be forced to stop according to the pressure drop rate abnormality coefficient, the pressure value unqualified coefficient and the equipment load coefficient includes:

[0029]

[0030] Wherein, Bgc is the evaluation coefficient, PL, Dax and WE are the pressure drop rate abnormal coefficient, pressure value unqualified coefficient and equipment load coefficient respectively, b1, b2 and b3 are the preset proportional coefficients of the pressure drop rate abnormal coefficient, pressure value unqualified coefficient and equipment load coefficient respectively, and b1, b2 and b3 are all greater than 0;

[0031] The evaluation coefficient is compared with a preset evaluation coefficient threshold. When the evaluation coefficient is greater than the preset evaluation coefficient threshold, the hydraulic press will enter a forced shutdown state and issue a third alarm.

[0032] Optionally, determining whether the part to be inspected has a defect includes:

[0033] Overlap the real-time pressure change curve within the preset holding time with the preset standard curve;

[0034] The real-time change curve within the preset holding time is recorded as P(t i ), the preset standard curve is recorded as S(t i ), i is the sequence number of the moments within the preset pressure holding time, i=u, u represents the total number of moments within the preset pressure holding time;

[0035] Calculate the real-time change curve P(t i ) and the preset standard curve S(t i ) is calculated as follows:

[0036] Calculate the real-time change curve P(t i ), the calculation formula is:

[0037] Calculate the preset standard curve S(t i ), the calculation formula is:

[0038] Calculate the overlap YH between the real-time change curve and the preset standard curve, the calculation formula is: YH = UH / ||P||·||S||;

[0039] The degree of overlap between the real-time change curve and the preset standard curve is compared with the preset minimum overlap threshold. If the degree of overlap is less than the preset minimum overlap threshold, it indicates that the inspected part has defects; if the degree of overlap is not less than the preset minimum overlap threshold, it indicates that the inspected part does not have defects.

[0040] In a second aspect of the present invention, an intelligent safety control device for a hydraulic press is provided, comprising:

[0041] The first judgment module: monitors the external state data of the hydraulic press in real time and makes judgments; if the external state data of the hydraulic press is normal, the hydraulic press is turned on to detect each part; the external state data includes whether the parts are installed in place, whether the air pressure is normal, and whether the parts are clamped;

[0042] The second judgment module: when the hydraulic press is turned on to detect each part, the instantaneous pressure of the hydraulic press is monitored, and the instantaneous pressure is compared with a preset instantaneous pressure threshold;

[0043] Control module: when the instantaneous pressure is greater than the preset instantaneous pressure threshold, the water drain valve and the air drain valve are opened to reduce the pressure, and the pressure drop rate within the preset time, the pressure value after it drops to the normal value, and the load of the hydraulic press during the drop determine whether the hydraulic press needs to be forced to stop;

[0044] Parts detection module: When the instantaneous pressure is not greater than the preset instantaneous pressure threshold, the valve switch is dynamically adjusted according to the pressure change. When the pressure reaches the normal value, the pressure is maintained, and the real-time pressure change curve within the preset pressure holding time is obtained. It is compared with the preset standard curve to determine whether the inspected parts have defects.

[0045] Beneficial effects of the present invention:

[0046] The present invention proposes an intelligent safety control method and device for a hydraulic press, which monitors the external state data of the hydraulic press in real time, and if there is no abnormality in the external state data of the hydraulic press, the hydraulic press is turned on to detect each part. When the hydraulic press is turned on to detect each part, the instantaneous pressure of the hydraulic press is monitored, and the instantaneous pressure is compared with a preset instantaneous pressure threshold. When the instantaneous pressure is greater than the preset instantaneous pressure threshold, the drain valve and the air release valve are opened to reduce the pressure, and the pressure is judged according to the pressure drop rate within a preset time, the pressure value after dropping to a normal value, and the load of the hydraulic press when it drops. Whether it is necessary to control the hydraulic press to force a shutdown; when the instantaneous pressure is not greater than the preset instantaneous pressure threshold, dynamically adjust the switch of the valve according to the pressure change. When the pressure reaches the proper value, maintain the pressure, obtain the real-time pressure change curve within the preset pressure holding time, and compare it with the preset standard curve to determine whether the inspected parts have defects; in this way, when performing defect detection on the parts of the hydraulic press, it is possible to ensure appropriate detection conditions before connecting the parts of the hydraulic press for defect detection, and take corresponding control measures to ensure the safety of the hydraulic press and reduce the risk of hydraulic press operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The present invention will be further described below in conjunction with the accompanying drawings.

[0048] Figure 1 It is a flow chart of an intelligent safety control method for a hydraulic press;

[0049] Figure 2 The figure is a framework diagram of an intelligent safety control device for a hydraulic press. DETAILED DESCRIPTION

[0050] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative work shall fall within the scope of protection of the present invention.

[0052] The embodiment of the present invention provides an intelligent safety control method for a hydraulic press. Figure 1 , Figure 1 A flowchart of an intelligent safety control method for a hydraulic press provided by an embodiment of the present invention. The method comprises the following steps:

[0053] Monitor the external status data of the hydraulic press in real time and make judgments; if there is no abnormality in the external status data of the hydraulic press, start the hydraulic press to detect each part; the external status data includes whether the parts are installed in place, whether the air pressure is normal, and whether the parts are clamped;

[0054] When the hydraulic press is turned on to inspect each part, the instantaneous pressure of the hydraulic press is monitored and compared with the preset instantaneous pressure threshold;

[0055] When the instantaneous pressure is greater than the preset instantaneous pressure threshold, the water drain valve and the air drain valve are opened to reduce the pressure, and the pressure drop rate within the preset time, the pressure value after it drops to the normal value, and the load of the hydraulic press during the drop determine whether the hydraulic press needs to be forced to stop;

[0056] When the instantaneous pressure is not greater than the preset instantaneous pressure threshold, the valve switch is dynamically adjusted according to the pressure change. When the pressure reaches the normal value, the pressure is maintained, and the real-time pressure change curve within the preset pressure holding time is obtained and compared with the preset standard curve to determine whether the inspected parts have defects.

[0057] Based on an intelligent safety control method for a hydraulic press provided in an embodiment of the present invention, through the above-mentioned method, when performing defect detection on the parts of the hydraulic press, it is possible to ensure suitable detection conditions before performing defect detection on the parts of the hydraulic press, and take corresponding control measures to ensure the safety of the hydraulic press and reduce the risk of operating the hydraulic press.

[0058] In one embodiment, real-time monitoring of external state data of the hydraulic press and making judgments include:

[0059] When the inspection parts are installed in place, the air pressure is normal and the parts are clamped, it is judged that the external state data of the hydraulic press is normal, and the hydraulic press is turned on to inspect the parts; if not, it is judged that the external state data of the hydraulic press is abnormal, the hydraulic press is not turned on to inspect the parts, and the first alarm is issued.

[0060] It should be noted that when all conditions are met, that is, the parts are installed in place, the air pressure is normal and the parts are clamped, the external state data of the hydraulic press is judged to be normal, and the hydraulic press can be safely opened for part inspection; if any one of the conditions is not met, such as the parts are not installed in place, the air pressure is abnormal or the parts are not clamped, the external state data is judged to be abnormal, and the hydraulic press is not allowed to be opened for inspection operations at this time, so as to avoid possible safety hazards and damage to the hydraulic press. At this time, the first alarm is issued to remind the staff to install the parts of the hydraulic press in place, clamp the parts, and adjust the air pressure to ensure that the air pressure is normal; and monitor the external state data of the hydraulic press in real time until the external state data of the hydraulic press is normal, and then open the hydraulic press to inspect each part; in this way, possible safety hazards and damage to the hydraulic press are avoided, and the hydraulic press is prevented from being pressed in dangerous situations, thereby preventing greater dangers in the future.

[0061] It should be noted that the above standards for whether the parts are installed in place, whether the air pressure is normal, and whether the parts are clamped are determined by professionals based on actual conditions, and are not specifically limited or elaborated on.

[0062] In one embodiment, when the hydraulic press is turned on to inspect each part, monitoring the instantaneous pressure of the hydraulic press and comparing the instantaneous pressure with a preset instantaneous pressure threshold comprises:

[0063] If the instantaneous pressure and the preset instantaneous pressure threshold are equal, it means that the hydraulic press is at risk of overload. At this time, it is necessary to open the water drain valve and the air drain valve to reduce the pressure and record whether the pressure drops to the normal value within the preset time. If the pressure does not drop to the normal value within the preset time, the hydraulic press will enter the forced shutdown state and issue a second alarm to prompt manual intervention;

[0064] When the pressure drops to a normal value within a preset time, it is determined whether the hydraulic press needs to be forced to stop based on the pressure drop rate within the preset time, the pressure value after dropping to the normal value, and the load of the hydraulic press during the drop.

[0065] It should be noted that the normal values ​​of the hydraulic press are set by professionals based on actual conditions and are not limited or elaborated on in detail.

[0066] For example, during the metal forming process, the hydraulic press needs to apply a specific pressure to achieve the shaping of the material; if the instantaneous pressure exceeds the preset instantaneous pressure threshold, it may mean that there is a system failure, such as poor sealing or hydraulic system leakage; in this case, if the pressure is not reduced in time, it may cause deformation of hydraulic press parts, breakage of welding points, and even explosion; therefore, by opening the drain valve and the air vent valve to quickly reduce the pressure, these risks can be effectively prevented to ensure the safety of the hydraulic press and the operator; if the pressure does not drop to the normal value within the preset time, this may indicate a serious fault in the system, such as hydraulic system leakage, valve failure, or pump failure. These faults will cause the hydraulic press to be unable to effectively reduce pressure, thereby increasing the safety risks of the hydraulic press and the operator; the activation of the forced shutdown state is to prevent the hydraulic press from continuing to operate under abnormally high pressure to avoid possible damage or accidents.

[0067] It should be noted that the preset instantaneous pressure threshold and the preset time are set by professionals according to actual conditions, and are not specifically limited or elaborated.

[0068] In one embodiment, judging whether it is necessary to control the hydraulic press to forcibly stop according to the pressure drop rate within a preset time, the pressure value after the pressure drops to a normal value, and the load of the hydraulic press during the drop includes:

[0069] The preset time is divided into several sub-time periods, the pressure drop rate in each sub-time period is obtained, and the pressure drop rate abnormality coefficient is calculated according to the preset pressure drop rate in each time period. The calculation formula is: Where PL is the pressure drop rate anomaly coefficient, Gf c is the actual pressure drop rate corresponding to the cth time period, Gt c The standard pressure drop rate preset for the cth sub-time period, ω c is the preset weight value of the pressure drop rate in the cth sub-time period, n is the total number of sub-time periods, and n is a positive integer;

[0070] Whether the hydraulic press needs to be forced to stop is determined based on the abnormal coefficient of the pressure drop rate, the pressure value after it drops to the normal value, and the load of the hydraulic press during the drop.

[0071] It should be noted that the preset time is divided into several sub-time periods by professionals based on actual conditions, and no detailed elaboration or limitation is made therein; in addition, the preset standard pressure drop rate and preset weight value for each sub-time period are also set by professionals based on actual conditions, and no detailed elaboration or limitation is made therein; in addition, the real-time pressure of the hydraulic press can be obtained through the internal pressure sensor, and the rate of air pressure drop can be calculated based on the specific length of time of each sub-time period, or other methods can be used, and no specific limitation or elaboration is made therein.

[0072] It should be noted that the pressure drop rate abnormality coefficient refers to the degree to which the actual pressure drop rate in each time period deviates from the preset normal pressure drop rate in the process of the pressure dropping to the normal value within the preset time; the greater the deviation, the greater the deviation, which means that even if the pressure drops to the normal value within the preset time, it may cause safety problems in the hydraulic press. The reason is that the deviation between the actual pressure drop rate and the preset rate indicates that the response is inconsistent during the pressure reduction process. The system's response time is too fast or too slow, which may mean that there are abnormal conditions inside the hydraulic press, such as inaccurate valve control, pipeline blockage, changes in hydraulic oil viscosity, etc.; although these problems do not show obvious faults in a short period of time, they may cause the performance of the hydraulic press to decline or the accumulation of safety hazards during long-term operation; when the actual drop rate deviates from the preset value, it means that the pressure control accuracy of the hydraulic press may decline. The precise operation of the hydraulic press depends on the high accuracy of the pressure control system. Once the accuracy is reduced, even if the pressure returns to normal within the preset time, uncontrollable errors may occur in subsequent operations due to the inaccuracy of the control system. Such errors will be accumulated and amplified in continuous operation, increasing the risk of the hydraulic press losing control. Therefore, when the abnormal coefficient of the pressure drop rate is too large, it is also necessary to control the hydraulic press to force a shutdown to ensure the safety of the hydraulic press.

[0073] In one embodiment, judging whether it is necessary to control the hydraulic press to forcibly stop according to the pressure drop rate abnormality coefficient, the pressure value after dropping to a normal value, and the load of the hydraulic press during the drop includes:

[0074] When the pressure drops to a normal value within a preset time, the pressure values ​​at multiple times in a subsequent preset stable time period are obtained, and the pressure values ​​at multiple times are compared with the normal values. When the pressure value and the normal value are greater than the normal value, the corresponding pressure value is marked as an abnormal pressure value;

[0075] The total number of abnormal pressure values ​​is divided by the total number of pressure values ​​in the preset stable time period to obtain the pressure value deviation coefficient;

[0076] Calculate the standard deviation of the pressure values ​​at multiple moments in the preset stable time period, and divide the standard deviation by the preset standard deviation threshold to obtain the pressure value fluctuation coefficient;

[0077] The pressure value deviation coefficient and the pressure value fluctuation coefficient are normalized to obtain the unqualified coefficient of the pressure value after the decrease, and whether the hydraulic press needs to be controlled to be forced to stop is determined based on the pressure decrease rate abnormality coefficient, the unqualified coefficient of the pressure value and the load of the hydraulic press during the decrease.

[0078] It should be noted that the standard deviation threshold and the preset stable time period are set by professionals according to the actual situation without specific limitation or elaboration. The preset stable time period generally refers to a period of time after the pressure value of the hydraulic press drops to the normal value, and the stability of the pressure is observed. The specific time period is set by professionals according to the actual situation without specific limitation.

[0079] It should be noted that the unqualified coefficient of pressure value after the drop refers to the degree of fluctuation of the pressure value and the degree to which the pressure value is greater than the normal value within a period of time after the pressure value of the hydraulic press drops to the normal value; if the greater the degree of fluctuation of the pressure value and the greater the degree to which the pressure value is greater than the normal value, it means that even if the pressure drops to the normal value within the preset time, it may cause safety problems in the hydraulic press. The reason is that even if the pressure drops to the normal value within the preset time, the pressure fluctuation is too large or exceeds the normal value during the stable time period, which may indicate that there are potential problems in the hydraulic press, such as component aging, hydraulic system leakage, etc.; these problems may cause the hydraulic press to repeatedly withstand excessive pressure, increase mechanical fatigue and wear, and even cause failures. Therefore, even if the hydraulic press returns to normal pressure in a short period of time, it is necessary to be vigilant about safety hazards and control the forced shutdown of the hydraulic press to ensure the safety of the hydraulic press.

[0080] It should be noted that the pressure value deviation coefficient and the pressure value fluctuation coefficient are normalized to obtain the formula for the unqualified coefficient of the pressure value after the decrease: Dax=a1×DE+a2×FE, where Dax is the unqualified coefficient of the pressure value, DE and FE are the pressure value deviation coefficient and the pressure value fluctuation coefficient, respectively, a1 and a2 are the preset proportional coefficients of the pressure value deviation coefficient and the pressure value fluctuation coefficient, respectively, and a1 and a2 are both greater than 0.

[0081] It should be noted that a1 and a2 are set by professionals according to actual conditions. Generally, the sum of a1 and a2 is 1. For example, a1 and a2 can be 0.5 and 0.5 respectively, or other numbers, without specific limitation.

[0082] In one embodiment, judging whether it is necessary to control the hydraulic press to forcibly stop according to the pressure drop rate abnormality coefficient, the pressure value unqualified coefficient and the load of the hydraulic press during the drop includes:

[0083] Obtaining the actual load value of the hydraulic press at multiple moments within the preset time of pressure drop, and dividing the actual load by the rated load value to obtain the load factor at the corresponding moment;

[0084] Record the load factor at all times, obtain the maximum load factor, and divide the maximum load factor by the preset maximum load value of the hydraulic press under normal reduced pressure to obtain the equipment load factor;

[0085] Determine whether the hydraulic press needs to be forced to shut down based on the pressure drop rate abnormality coefficient, pressure value unqualified coefficient and equipment load coefficient.

[0086] It should be noted that within the preset time of pressure drop, the actual load values ​​of the hydraulic press at multiple moments can be collected and obtained in real time through the load sensor installed on the hydraulic press; the rated load value can be directly obtained from the production manual; in addition, the preset maximum load value is set by professionals based on actual conditions and is not specifically limited.

[0087] It should be noted that the larger the equipment load factor, the closer the load that the hydraulic press bears in actual work is to or exceeds its rated load, which means that even if the pressure returns to normal, there may still be a risk of overload operation of the hydraulic press, increasing the possibility of failure and safety hazards. At this time, it is necessary to control the hydraulic press to force a shutdown to ensure the safety of the hydraulic press.

[0088] In one embodiment, judging whether it is necessary to control the hydraulic press to be forced to stop according to the pressure drop rate abnormality coefficient, the pressure value unqualified coefficient and the equipment load coefficient includes:

[0089]

[0090] Wherein, Bgc is the evaluation coefficient, PL, Dax and WE are the pressure drop rate abnormal coefficient, pressure value unqualified coefficient and equipment load coefficient respectively, b1, b2 and b3 are the preset proportional coefficients of the pressure drop rate abnormal coefficient, pressure value unqualified coefficient and equipment load coefficient respectively, and b1, b2 and b3 are all greater than 0;

[0091] The evaluation coefficient is compared with a preset evaluation coefficient threshold. When the evaluation coefficient is greater than the preset evaluation coefficient threshold, the hydraulic press will enter a forced shutdown state and issue a third alarm to prompt that manual intervention is required.

[0092] It should be noted that b1, b2, and b3 are set by professionals according to actual conditions. Generally, the sum of b1, b2, and b3 is 1. For example, b1, b2, and b3 can be 0.3, 0.3, and 0.4, respectively, or other numbers, which are not specifically limited.

[0093] It should be noted that the preset evaluation coefficient threshold is set by professionals based on actual circumstances and is not specifically limited.

[0094] It should be noted that when the evaluation coefficient is greater than the preset evaluation coefficient threshold, it means that even if the pressure drops to a normal value within the preset time, the drop does not meet the preset standard. At this time, in order to ensure the safety of the hydraulic press, the hydraulic press is shut down in time and the third alarm is issued to remind the staff to take corresponding measures in time to ensure the safety of the water pressure and perform defect detection on the parts of the hydraulic press.

[0095] It should be noted that when the instantaneous pressure is not greater than the preset instantaneous pressure threshold, the valve switch is dynamically adjusted according to the pressure change. When the pressure reaches the normal value, the pressure is maintained, and the real-time pressure change curve within the preset pressure holding time is obtained and compared with the preset standard curve to determine whether the inspected parts have defects.

[0096] In one embodiment, determining whether the part to be inspected has defects includes:

[0097] Overlap the real-time pressure change curve within the preset holding time with the preset standard curve;

[0098] The real-time change curve within the preset holding time is recorded as P(t i ), the preset standard curve is recorded as S(t i ), i is the sequence number of the moments within the preset pressure holding time, i=u, u represents the total number of moments within the preset pressure holding time;

[0099] Calculate the real-time change curve P(t i ) and the preset standard curve S(t i ) is calculated as follows:

[0100] Calculate the real-time change curve P(t i ), the calculation formula is:

[0101] Calculate the preset standard curve S(t i ), the calculation formula is:

[0102] Calculate the overlap YH between the real-time change curve and the preset standard curve, the calculation formula is: YH = UH / ||P||·||S||;

[0103] The degree of overlap between the real-time change curve and the preset standard curve is compared with the preset minimum overlap threshold. If the degree of overlap is less than the preset minimum overlap threshold, it indicates that the inspected part has defects; if the degree of overlap is not less than the preset minimum overlap threshold, it indicates that the inspected part does not have defects.

[0104] It should be noted that the preset minimum overlap threshold is set by professionals based on actual conditions, and no specific limitation or elaboration is made;

[0105] In one implementation, by calculating the degree of overlap between the real-time change curve and the preset standard curve, an accurate assessment of the part status can be achieved, thereby discovering potential problems in a timely manner and ensuring product quality.

[0106] Based on the same inventive concept, the present invention also provides an intelligent safety control device for a hydraulic press. Figure 2 , Figure 2 A framework diagram of an intelligent safety control device for a hydraulic press provided by an embodiment of the present invention, the device comprising:

[0107] The first judgment module: monitors the external state data of the hydraulic press in real time and makes judgments; if the external state data of the hydraulic press is normal, the hydraulic press is turned on to detect each part; the external state data includes whether the parts are installed in place, whether the air pressure is normal, and whether the parts are clamped;

[0108] The second judgment module: when the hydraulic press is turned on to detect each part, the instantaneous pressure of the hydraulic press is monitored, and the instantaneous pressure is compared with a preset instantaneous pressure threshold;

[0109] Control module: when the instantaneous pressure is greater than the preset instantaneous pressure threshold, the water drain valve and the air drain valve are opened to reduce the pressure, and the pressure drop rate within the preset time, the pressure value after it drops to the normal value, and the load of the hydraulic press during the drop determine whether the hydraulic press needs to be forced to stop;

[0110] Parts detection module: When the instantaneous pressure is not greater than the preset instantaneous pressure threshold, the valve switch is dynamically adjusted according to the pressure change. When the pressure reaches the normal value, the pressure is maintained, and the real-time pressure change curve within the preset pressure holding time is obtained. It is compared with the preset standard curve to determine whether the inspected parts have defects.

[0111] Based on an intelligent safety control device for a hydraulic press provided in an embodiment of the present invention, through the above method, when performing defect detection on the parts of the hydraulic press, it is possible to ensure suitable detection conditions before performing defect detection on the parts of the hydraulic press, and take corresponding control measures to ensure the safety of the hydraulic press and reduce the risk of operating the hydraulic press.

[0112] The above is a detailed description of an embodiment of the present invention, but the content is only a preferred embodiment of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. An intelligent safety control method for a hydraulic press, characterized in that: The following steps are involved: Monitor the external state data of the hydraulic press in real time and make judgments; if there is no abnormality in the external state data of the hydraulic press, start the hydraulic press to detect each part; the external state data includes whether the parts are installed in place, whether the air pressure is normal, and whether the parts are clamped; When the hydraulic press is turned on to inspect each part, the instantaneous pressure of the hydraulic press is monitored and compared with the preset instantaneous pressure threshold; When the instantaneous pressure is greater than the preset instantaneous pressure threshold, the water drain valve and the air drain valve are opened to reduce the pressure, and the pressure drop rate within the preset time, the pressure value after it drops to the normal value, and the load of the hydraulic press during the drop determine whether the hydraulic press needs to be forced to stop; When the instantaneous pressure is not greater than the preset instantaneous pressure threshold, the valve switch is dynamically adjusted according to the pressure change. When the pressure reaches the normal value, the pressure is maintained, and the real-time pressure change curve within the preset pressure holding time is obtained and compared with the preset standard curve to determine whether the inspected parts have defects.

2. The intelligent safety control method for a hydraulic press according to claim 1, characterized in that: Real-time monitoring of the external status data of the hydraulic press and judgment including: When the inspection parts are installed in place, the air pressure is normal and the parts are clamped, it is judged that the external state data of the hydraulic press is normal, and the hydraulic press is turned on to inspect the parts; if not, it is judged that the external state data of the hydraulic press is abnormal, the hydraulic press is not turned on to inspect the parts, and the first alarm is issued.

3. The intelligent safety control method for a hydraulic press according to claim 1, characterized in that: Comparing the instantaneous pressure to a preset instantaneous pressure threshold includes: If the instantaneous pressure is equal to the preset instantaneous pressure threshold, the water drain valve and the air drain valve are opened to reduce the pressure, and whether the pressure drops to the normal value within the preset time is recorded. If the pressure does not drop to the normal value within the preset time, the hydraulic press will enter the forced shutdown state and issue a second alarm; When the pressure drops to a normal value within a preset time, it is determined whether the hydraulic press needs to be forced to stop based on the pressure drop rate within the preset time, the pressure value after dropping to the normal value, and the load of the hydraulic press during the drop.

4. The intelligent safety control method for a hydraulic press according to claim 3 is characterized in that: Judging whether the hydraulic press needs to be forced to stop based on the pressure drop rate within the preset time, the pressure value after it drops to the normal value, and the load of the hydraulic press during the drop includes: The preset time is divided into several sub-time periods, the pressure drop rate in each sub-time period is obtained, and the pressure drop rate abnormality coefficient is calculated according to the preset pressure drop rate in each time period. The calculation formula is: Where PL is the pressure drop rate anomaly coefficient, Gf c is the actual pressure drop rate corresponding to the cth time period, Gt c The standard pressure drop rate preset for the cth sub-time period, ω c is the preset weight value of the pressure drop rate in the cth sub-time period, n is the total number of sub-time periods, and n is a positive integer; Whether the hydraulic press needs to be forced to stop is determined based on the abnormal coefficient of the pressure drop rate, the pressure value after it drops to the normal value, and the load of the hydraulic press during the drop.

5. The intelligent safety control method for a hydraulic press according to claim 4, characterized in that: Judging whether the hydraulic press needs to be forced to stop based on the abnormal coefficient of the pressure drop rate, the pressure value after it drops to the normal value, and the load of the hydraulic press during the drop includes: When the pressure drops to a normal value within a preset time, the pressure values ​​at multiple times in a subsequent preset stable time period are obtained, and the pressure values ​​at multiple times are compared with the normal values. When the pressure value and the normal value are greater than the normal value, the corresponding pressure value is marked as an abnormal pressure value; The total number of abnormal pressure values ​​is divided by the total number of pressure values ​​in the preset stable time period to obtain the pressure value deviation coefficient; Calculate the standard deviation of the pressure values ​​at multiple moments in the preset stable time period, and divide the standard deviation by the preset standard deviation threshold to obtain the pressure value fluctuation coefficient; The pressure value deviation coefficient and the pressure value fluctuation coefficient are normalized to obtain the unqualified coefficient of the pressure value after the decrease, and whether the hydraulic press needs to be controlled to be forced to stop is determined based on the pressure decrease rate abnormality coefficient, the unqualified coefficient of the pressure value and the load of the hydraulic press during the decrease.

6. The intelligent safety control method for a hydraulic press according to claim 5, characterized in that: Judging whether the hydraulic press needs to be forced to stop based on the abnormal coefficient of pressure drop rate, the unqualified coefficient of pressure value and the load of the hydraulic press during the drop includes: Obtaining the actual load value of the hydraulic press at multiple moments within the preset time of pressure drop, and dividing the actual load by the rated load value to obtain the load factor at the corresponding moment; Record the load factor at all times, obtain the maximum load factor, and divide the maximum load factor by the preset maximum load value of the hydraulic press under normal reduced pressure to obtain the equipment load factor; Determine whether the hydraulic press needs to be forced to shut down based on the pressure drop rate abnormality coefficient, pressure value unqualified coefficient and equipment load coefficient.

7. The intelligent safety control method for a hydraulic press according to claim 6, characterized in that: Judging whether it is necessary to control the hydraulic press to shut down by force according to the abnormal coefficient of pressure drop rate, unqualified coefficient of pressure value and equipment load coefficient includes: Wherein, Bgc is the evaluation coefficient, PL, Dax and WE are the pressure drop rate abnormal coefficient, pressure value unqualified coefficient and equipment load coefficient respectively, b1, b2 and b3 are the preset proportional coefficients of the pressure drop rate abnormal coefficient, pressure value unqualified coefficient and equipment load coefficient respectively, and b1, b2 and b3 are all greater than 0; The evaluation coefficient is compared with a preset evaluation coefficient threshold. When the evaluation coefficient is greater than the preset evaluation coefficient threshold, the hydraulic press will enter a forced shutdown state and issue a third alarm.

8. The intelligent safety control method for a hydraulic press according to claim 1, characterized in that: Determining whether the part to be inspected has defects includes: Overlap the real-time pressure change curve within the preset holding time with the preset standard curve; The real-time change curve within the preset holding time is recorded as P(t i ), the preset standard curve is recorded as S(t i ), i is the sequence number of the moments within the preset pressure holding time, i=u, u represents the total number of moments within the preset pressure holding time; Calculate the real-time change curve P(t i ) and the preset standard curve S(t i ) is calculated as follows: Calculate the real-time change curve P(t i ), the calculation formula is: Calculate the preset standard curve S(t i ), the calculation formula is: Calculate the overlap YH between the real-time change curve and the preset standard curve, the calculation formula is: YH = UH / ||P||·||S||; The degree of overlap between the real-time change curve and the preset standard curve is compared with the preset minimum overlap threshold. If the degree of overlap is less than the preset minimum overlap threshold, it indicates that the inspected part has defects; if the degree of overlap is not less than the preset minimum overlap threshold, it indicates that the inspected part does not have defects.

9. An intelligent safety control device for a hydraulic press, characterized in that: The device comprises: The first judgment module: monitors the external state data of the hydraulic press in real time and makes judgments; if the external state data of the hydraulic press is normal, the hydraulic press is turned on to detect each part; the external state data includes whether the parts are installed in place, whether the air pressure is normal, and whether the parts are clamped; The second judgment module: when the hydraulic press is turned on to detect each part, the instantaneous pressure of the hydraulic press is monitored, and the instantaneous pressure is compared with a preset instantaneous pressure threshold; Control module: when the instantaneous pressure is greater than the preset instantaneous pressure threshold, the water drain valve and the air drain valve are opened to reduce the pressure, and the pressure drop rate within the preset time, the pressure value after it drops to the normal value, and the load of the hydraulic press during the drop determine whether the hydraulic press needs to be forced to stop; Parts detection module: When the instantaneous pressure is not greater than the preset instantaneous pressure threshold, the valve switch is dynamically adjusted according to the pressure change. When the pressure reaches the normal value, the pressure is maintained, and the real-time pressure change curve within the preset pressure holding time is obtained. It is compared with the preset standard curve to determine whether the inspected parts have defects.

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