JP2018105161A - Anomaly detection device for hydraulic pressure rotary machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device that can early detect occurrence of anomaly when such an anomaly as galling between a shoe plate of a hydraulic pressure rotary machine and a shoe or swash plate occurs.SOLUTION: An anomaly detection device for a hydraulic pressure rotary machine 1 includes: rotational state detection parts 20a, 20b for detecting a rotational state of a shoe plate 16; and an anomaly detection processing part 5 for detecting occurrence of anomaly in the hydraulic pressure rotary machine 1 based on the rotational state of the shoe plate 16 that is indicated by output from the rotational state detection parts 20a, 20b.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an apparatus for detecting an abnormality of a hydraulic rotating machine mounted on a construction machine or the like.

  As a technique for detecting an abnormality in a hydraulic rotary machine such as a hydraulic pump or a hydraulic motor, for example, a technique proposed in Patent Document 1 is known.

  In this technique, a pressure change in the casing of the hydraulic rotating machine is detected, and occurrence of an abnormality (such as galling between the cylinder and the piston) that causes leakage of hydraulic oil is detected based on the detected pressure change.

JP 2000-274378 A

  Incidentally, the hydraulic rotating machine described in Patent Document 1 is a rotating machine in which a shoe engaged with a tip portion of a piston is directly slidably contacted with a swash plate. A hydraulic rotating machine having a structure in which a shoe plate is interposed between the shoe plate and the shoe plate is in sliding contact with the shoe and the swash plate via an oil film is generally known.

  In this type of hydraulic rotating machine, galling or the like occurs between the shoe plate and the shoe or swash plate due to wear powder, etc., and the sliding between the shoe plate and the shoe or swash plate does not occur. It may not be performed smoothly. Such an abnormality may cause malfunctions of the hydraulic rotating machine or malfunctions such as failure, so it is desirable that it can be detected at an early stage.

  However, in the conventional technique as seen in Patent Document 1, since the occurrence of abnormality is detected based on the change in pressure of the hydraulic oil, abnormality such as galling is generated between the shoe plate and the shoe or swash plate. In the initial stage of occurrence, it was difficult to detect the occurrence of the abnormality.

  The present invention has been made in view of such a background, and when an abnormality such as galling occurs between a shoe plate of a hydraulic rotating machine and a shoe or a swash plate, the occurrence of the abnormality is detected at an early stage. It is an object of the present invention to provide an apparatus capable of performing the above.

In order to achieve the above object, an abnormality detection device for a hydraulic rotating machine according to the present invention is provided with a piston slidably attached to a cylinder block that can rotate integrally with a rotating shaft, and attached to the tip of the piston. A shoe, a swash plate disposed on the front end side of the piston, and the shoe and the swash plate interposed between the shoe and the swash plate so as to be able to rotate with the rotation of the rotary shaft while being in sliding contact with the shoe and the swash plate. An abnormality detection device for a hydraulic rotating machine comprising a shoe plate,
A rotation state detection unit for detecting a rotation state of the shoe plate;
An abnormality detection processing unit that detects occurrence of an abnormality of the hydraulic rotating machine based on a rotation state of the shoe plate indicated by an output of the rotation state detection unit (first invention).

  Here, when an abnormality such as galling occurs between the shoe plate and the shoe or the swash plate, even if the hydraulic rotating machine can perform a required operation, the rotation state of the shoe plate However, it tends to be in a rotation state different from the normal case. Accordingly, when an abnormality such as a galling is detected by detecting the occurrence of an abnormality in the hydraulic rotating machine based on the rotation state of the shoe plate indicated by the output of the rotation state detection unit, the abnormality is detected. It is possible to quickly detect the occurrence of.

  Therefore, according to the present invention, according to the first invention, when an abnormality such as galling occurs between the shoe plate and the shoe or the swash plate, the occurrence of the abnormality can be detected at an early stage.

  In the first aspect of the invention, the abnormality detection processing unit detects occurrence of an abnormality of the hydraulic rotating machine based on a detected value of a rotation speed of the shoe plate indicated by an output of the rotation state detection unit. It is preferable to be comprised (2nd invention).

  That is, when an abnormality such as galling occurs, the rotational speed of the shoe plate is particularly susceptible to influence. Therefore, according to the second invention, it is possible to preferably detect the occurrence of abnormality of the hydraulic rotating machine.

  In the second aspect of the invention, the abnormality detection processing unit determines whether the detected value of the rotation speed of the shoe plate deviates from a normal range set according to the rotation speed of the rotation shaft. It is preferable to be configured to detect the occurrence of an abnormality in the pressure rotating machine (third invention).

  Here, according to various experiments and examinations of the inventors of the present application, in a normal hydraulic rotating machine in which the galling or the like does not occur, the rotational speed of the shoe plate tends to be within a certain range, Is dependent on the rotational speed of the rotating shaft.

  Therefore, in the third invention, the abnormality detection processing unit is configured as described above. Thereby, it is possible to appropriately detect the occurrence of the abnormality of the hydraulic rotating machine with high reliability.

  In the first to third aspects of the invention, the abnormality detection processing unit detects occurrence of an abnormality in the hydraulic rotating machine on the condition that the operation state of the hydraulic pump is a predetermined operation state determined in advance. (4th invention).

  According to this, since the operation state of the hydraulic pump that detects the occurrence of the abnormality of the hydraulic rotating machine is limited to the predetermined operation state, the detection of the occurrence of the abnormality is detected. Therefore, it is possible to carry out in a suitable operating state.

  In the fourth aspect of the invention, when the hydraulic rotating machine is, for example, a variable displacement pump capable of changing the inclination angle of the swash plate, the predetermined operating state is that the inclination angle of the swash plate is It is preferable that the operating state is maintained at a constant inclination angle (fifth invention).

  According to this, it is possible to detect the occurrence of an abnormality in the hydraulic rotating machine in a situation where the rotation state of the shoe plate is easily maintained stably. As a result, the reliability of detection of the occurrence of the abnormality can be improved.

  In the fourth aspect of the present invention, when the hydraulic rotating machine is a variable displacement hydraulic pump that is mounted on, for example, a construction machine and can change the inclination angle of the swash plate, the predetermined operation state Is a first operating state in which the tilt angle of the swash plate is kept at the minimum tilt angle while the rotary shaft of the hydraulic pump is driven to rotate by the engine in the idling operation state, and the tilt angle of the swash plate is set to the maximum tilt angle. It is preferable to include at least one operation state of the second operation state in which the hydraulic oil is supplied from the hydraulic pump to the hydraulic actuator.

  According to various experiments and examinations by the inventors of the present application, when the hydraulic pump as a hydraulic rotating machine is in a normal state, the rotation state of the shoe plate in the first operation state and the second operation state is easily maintained stably. . For this reason, when the abnormality of the hydraulic pump due to the galling or the like occurs, the occurrence of the abnormality can be detected with high reliability based on the rotation state of the shoe plate.

The figure which shows schematic structure of a hydraulic apparatus provided with the hydraulic pump as a hydraulic rotary machine in 1st Embodiment of this invention. 2A and 2B are diagrams each showing a configuration of a hydraulic pump according to the first embodiment. The figure which shows the structure of the shoe plate of the hydraulic pump in 1st Embodiment. The flowchart which shows the process in 1st Embodiment of the control apparatus shown in FIG. The graph which shows the relationship between the rotation speed of the engine which drives the rotating shaft of a hydraulic pump, and the normal range of the rotation speed of the shoe plate of a hydraulic pump. The figure which shows the structure of the hydraulic pump in 2nd Embodiment. The flowchart which shows the process in 3rd Embodiment of the control apparatus shown in FIG.

[First Embodiment]
An embodiment of the present invention will be described below with reference to FIGS. First, an outline of a hydraulic apparatus A including a swash plate type hydraulic pump 1 as an example of a hydraulic rotating machine will be described with reference to FIG. 1 is a hydraulic device mounted on a construction machine such as a hydraulic excavator, for example, and includes a hydraulic pump 1, an engine 2 as a power source of the hydraulic pump 1, a hydraulic cylinder or a hydraulic motor, and the like. , A control valve unit 4 in which a control valve (not shown) such as a direction switching valve for each hydraulic actuator 3 is incorporated, and a control device 5.

  The control device 5 is composed of one or more electronic circuit units including a CPU, a RAM, a ROM, an interface circuit, etc., and relates to the operation control of the hydraulic device A as a function realized by a mounted hardware configuration or program. It has a function to execute processing and a function to execute processing related to abnormality detection of the hydraulic pump 1.

  In this hydraulic apparatus A, the hydraulic pump 1 discharges the hydraulic oil while sucking the hydraulic oil from the hydraulic oil tank 6 in a state where the rotary shaft 11 as the power input shaft is rotationally driven by the engine 2. Then, the hydraulic oil discharged from the hydraulic pump 1 is supplied to the hydraulic actuator 3 to be actuated via the control valve unit 4, and the hydraulic actuator 3 is driven.

  In this case, a pilot pressure corresponding to the operation amount of an operation lever (not shown) corresponding to the hydraulic actuator 3 to be actuated is input to the control valve unit 4 and corresponds to the hydraulic actuator 3 to be actuated according to the pilot pressure. The direction switching valve is driven.

  In the present embodiment, the hydraulic pump 1 is a variable displacement hydraulic pump, and its discharge flow rate can be variably controlled via the regulator 1a. The regulator 1 a is an actuator that tilts a later-described swash plate of the hydraulic pump 1, and is controlled by the control device 5.

  In this case, the pilot pressure input to the control valve unit 4 is detected by the pressure sensor 7 as data indicating the required value of the flow rate of the hydraulic oil to be supplied to the hydraulic actuator 3 to be operated, and the detection of the pressure sensor 7 Data is input to the control device 5. Then, the control device 5 increases the discharge flow rate of the hydraulic pump 1 as the detected value of the pilot pressure is larger (in other words, the required value of the flow rate of the hydraulic oil to be supplied to the hydraulic actuator 3 is larger). The regulator 1a is controlled.

  The engine 2 performs an idling operation at a predetermined rotational speed in a state where all the hydraulic actuators 3 are stopped. When any of the hydraulic actuators 3 is operated, the hydraulic pump has a rotational speed higher than the idling rotational speed. It is controlled so that one rotation shaft 11 is rotationally driven.

  Next, the configuration of the hydraulic pump 1 will be described with reference to FIG. 2A or 2B. The basic configuration of the hydraulic pump 1 is a known configuration, and FIG. 2A or 2B schematically shows the basic configuration.

  As shown in the figure, the hydraulic pump 1 includes a rotating shaft 11, a cylinder block 12 fixed to the rotating shaft 11 so as to rotate integrally with the rotating shaft 11, and a plurality of slidably attached to the cylinder block 12. Piston 13, a shoe 14 attached to the tip of each piston 13, a swash plate 15 disposed on the tip of the piston 13, and a shoe plate interposed between the swash plate 15 and the shoe 14. 16 and a casing 17.

  The cylinder block 12, piston 13, shoe 14, swash plate 15 and shoe plate 16 are accommodated in a casing 17.

  The rotating shaft 11 extends through the inside of the casing 17 and is rotatably supported by the casing 17 via a bearing (not shown). The rotary shaft 11 passes through the center of the cylinder block 12 and is coupled to the cylinder block 12.

  In the cylinder block 12, a plurality of piston insertion holes 12 a (the same number as the pistons 13) extending in parallel with the rotation shaft 11 are formed around the rotation shaft 11. Each piston 13 is slidably inserted into each piston insertion hole 12a.

  The tip of each piston 13 protrudes from the piston insertion hole 12a toward the swash plate 15, and a spherical portion 13a is formed at the tip. A shoe 14 is slidably fitted to the spherical portion 13 a of each piston 13.

  The swash plate 15 has a hole (not shown) having a diameter larger than that of the rotating shaft 11 at the center thereof, and is externally inserted into the rotating shaft 11 through the hole. The swash plate 15 can be tilted within a predetermined angle range with respect to the rotary shaft 11 by the regulator 1a (not shown in FIGS. 2A and 2B). 2A shows a state in which the swash plate 15 is in a vertical posture or a substantially vertical posture with respect to the rotation shaft 11 (hereinafter referred to as a minimum tilt state), and FIG. 2B shows that the swash plate 15 is in a maximum state from the minimum tilt state. 2 shows a tilted state (hereinafter referred to as a maximum tilted state).

  The shoe plate 16 is interposed so as to be sandwiched between the swash plate 15 and the shoe 14 fitted to the spherical portion 13 a of each piston 13, and can be tilted together with the swash plate 15. The shoe plate 16 is in sliding contact with the swash plate 15 and each shoe 14 so that the shoe plate 16 can rotate relative to the swash plate 15 and each shoe 14 about the axis of the rotary shaft 11.

  In this case, when the hydraulic pump 1 is operated, hydraulic oil is supplied to the front and back surfaces of the shoe plate 16 so that the shoe plate 16 is in sliding contact with the swash plate 15 and each shoe 14 via an oil film formed by the hydraulic oil. It has become.

  In each piston insertion hole 12 a, the space on the rear end side of the piston 13 is an oil chamber 18. The oil chamber 18 is moved from the rear end face side of the cylinder block 12 (at the end face side opposite to the swash plate 15 of both end faces of the cylinder block 12) when the pistons 13 slide with the rotation of the rotary shaft 11. The hydraulic oil enters and exits through a valve plate (not shown).

  More specifically, when the piston 13 inserted into each piston insertion hole 12a slides in a direction projecting from the piston insertion hole 12a, the hydraulic oil enters the oil chamber 18 of the piston insertion hole 12a via the valve plate. Sucked. Further, when the piston 13 slides in the direction of being buried in the piston insertion hole 12a, the hydraulic oil is discharged from the oil chamber 18 of the piston insertion hole 12a.

  In the hydraulic pump 1 having such a configuration, each piston 13 is rotated along the piston insertion hole 12a by rotating the rotary shaft 11 while the swash plate 15 is inclined from the minimum tilt state. Reciprocates in the center direction. Accordingly, inflow (suction) and outflow (discharge) of the hydraulic oil in the oil chamber 18 of each piston insertion hole 12a are repeated. Then, the hydraulic oil discharged from the oil chamber 18 of each piston insertion hole 12a is discharged from the discharge port of the hydraulic pump 1.

  Next, a configuration and processing for detecting the occurrence of an abnormality in the hydraulic pump 1 having such a configuration will be described.

  In the present embodiment, the hydraulic pump 1 is provided with a configuration for detecting the rotation state of the shoe plate 16 in order to detect the occurrence of an abnormality in the hydraulic pump 1. Specifically, as shown in FIG. 3, a plurality of protrusions 16 a are formed at equiangular intervals on the outer periphery of the shoe plate 16. 2A and 2B, the two rotation detection sensors 20a and 20b are attached to the casing 17 so as to face the outer periphery of the shoe plate 16.

  These rotation detection sensors 20a and 20b correspond to a rotation state detection unit in the present invention. Of these rotation detection sensors 20a and 20b, the rotation detection sensor 20a is a sensor for detecting the rotation state of the shoe plate 16 in the minimum tilt state of the swash plate 15, and in the minimum tilt state. It arrange | positions so that the outer periphery of this shoe plate 16 may be opposed (refer FIG. 2A).

  The rotation detection sensor 20b is a sensor for detecting the rotation state of the shoe plate 16 in the maximum tilt state of the swash plate 15, and faces the outer periphery of the shoe plate 16 in the maximum tilt state. In place (see FIG. 2B).

  These rotation detection sensors 20a and 20b are composed of, for example, a pickup sensor, a proximity switch, and the like. Each time the rotation detection sensors 20a and 20b face the protrusion 16a of the shoe plate 16 (in other words, every predetermined rotation angle of the shoe plate 16) Is output. That is, the rotation detection sensors 20a and 20b output pulse signals synchronized with the rotation speed (rotational speed) of the shoe plate 16 in each of the minimum tilt state and the maximum tilt state of the swash plate 15.

  As the rotation detection sensors 20a and 20b, for example, an optical sensor, a capacitive sensor, or the like can be used.

  As shown in FIG. 1, in addition to the detection signal of the pressure sensor 7, the detection signal of the rotation detection sensors 20 a and 20 b is input to the control device 5, and the rotation speed Ne (= hydraulic pump 1 of the engine 2). A detection signal indicating the rotation speed of the rotation shaft 11 is input from a rotation speed sensor (not shown).

  And the control apparatus 5 has a function which performs the abnormality detection process which detects generation | occurrence | production of abnormality of the hydraulic pump 1 using the detected value shown by these detection signals. In this abnormality detection process, the control device 5 indicates that the detected value of the rotation speed (rotational speed) of the shoe plate 16 indicated by the detection signal of the rotation detection sensor 20a or 20b in a specific operation state of the hydraulic pump 1 is a predetermined value. The occurrence of abnormality of the hydraulic pump 1 is detected by monitoring whether or not it is in the normal range.

  In the present embodiment, since the control device 5 has a function of executing the abnormality detection process, the control device 5 has a function as an abnormality detection processing unit in the present invention.

  Below, the abnormality detection process which the control apparatus 5 performs is demonstrated. The control device 5 executes the processing shown in the flowchart of FIG. 4 at a predetermined processing cycle during operation of the hydraulic device A (specifically, during operation in which the engine 2 is activated).

  In STEP 1, the control device 5 determines whether or not the current operation state of the hydraulic pump 1 is one of a first operation state and a second operation state that are predetermined as two types of specific operation states. to decide.

  The first operating state and the second operating state are compared in terms of the stability of the rotational speed of the shoe plate 16 and the temperature of the hydraulic oil supplied to the shoe plate 16 in a situation where the hydraulic pump 1 is operating normally. As an operation state that is extremely high, the operation state is determined in advance based on experiments or the like.

  More specifically, the situation in which the hydraulic pump 1 is operating normally means that sliding between the shoe plate 16 and each of the swash plate 15 and the shoe 14 is hindered by abrasion powder or the like. It is a situation that is performed smoothly.

  In the present embodiment, the first operation state is a state in which, for example, all the hydraulic actuators 3 are stopped and the rotary shaft 11 of the hydraulic pump 1 is rotationally driven by the engine 2 in the idling operation state. is there. In other words, the first operation state is a state in which the swash plate 15 of the hydraulic pump 1 is maintained in the minimum tilt state.

  Further, in the second operation state, for example, the operating lever of any hydraulic actuator 3 is operated with a maximum or a predetermined operation amount or more, and the hydraulic pump 1 is operated with the maximum discharge flow rate, and the hydraulic pressure to be operated is set. In this state, hydraulic oil is supplied to the actuator 3. In other words, the second operation state is a state in which the swash plate 15 of the hydraulic pump 1 is maintained in the maximum tilt state.

  The determination process in STEP 1 can be performed based on, for example, the pilot pressure indicated by the detection signal of the pressure sensor 7. That is, for any hydraulic actuator 3, the operating state of the hydraulic pump 1 depends on whether the detected value of the pilot pressure is smaller than a predetermined value (whether it is zero or almost zero). It can be determined whether or not.

  Further, the operation state of the hydraulic pump 1 depends on whether the detected value of the pilot pressure for any of the hydraulic actuators 3 is larger than a predetermined value (whether it is a maximum value or a substantially maximum value). It can be determined whether or not it is in an operating state.

  The determination process in STEP 1 is based on, for example, a detection value of an actual operation amount of the operation lever of each hydraulic actuator 3, a control command for the engine 2 generated by the control device 5, a control command for the regulator 1a of the hydraulic pump 1, or the like. It is also possible to do this.

  If the determination result in STEP 1 is negative, the control device 5 ends the processing in the current processing cycle.

  On the other hand, when the determination result of STEP 1 is affirmative (when the operation state of the hydraulic pump 1 is the first operation state or the second operation state), the control device 5 performs the current rotation of the engine 2 in STEP 2. The detected value of the number Ne (= the rotational speed of the rotating shaft 11 of the hydraulic pump 1) and the detected value of the current rotational speed Np of the shoe plate 16 of the hydraulic pump 1 are acquired.

  In this case, when the operation state of the hydraulic pump 1 is the first operation state, the detected value of the rotation speed Np of the shoe plate 16 is a detection value indicated by the detection signal of the rotation detection sensor 20a. When the operation state of the hydraulic pump 1 is the second operation state, the detected value of the rotation speed Np of the shoe plate 16 is a detection value indicated by the detection signal of the rotation detection sensor 20b.

  Thereby, the rotational speed Np of the shoe plate 16 can be properly detected in both the first operation state and the second operation state.

  Next, in STEP 3, the control device 5 determines whether or not the detected value of the rotational speed Np of the shoe plate 16 deviates from a predetermined normal range.

  In the present embodiment, the normal range is a range that is variably set according to the rotational speed Ne of the engine 2 as shown in FIG.

  In this case, the higher the rotational speed Ne of the engine 2 (the higher the rotational speed of the rotary shaft 11 of the hydraulic pump 1), the larger the upper limit value and lower limit value of the normal range of the rotational speed Np of the shoe plate 16; The normal range is set according to the detected value of the rotational speed Ne of the engine 2 so that the width of the normal range (difference between the upper limit value and the lower limit value) becomes large.

  Thus, by setting the normal range of the rotational speed Np of the shoe plate 16 in accordance with the detected value of the rotational speed Ne of the engine 2 (= the rotational speed of the rotational shaft 11 of the hydraulic pump 1), the rotational shaft of the hydraulic pump 1 is set. Dependency of the rotational speed Np of the shoe plate 16 on the rotational speed (rotational speed) of 11 or dependence of the rotational speed Np of the shoe plate 16 on the temperature rising state of the oil film formed on the front and back surfaces of the shoe plate 16 In the reflected form, the normal range of the rotational speed Np of the shoe plate 16 can be set to an appropriate range according to the substance.

  When the determination result in STEP 3 is negative (when the rotation speed Np of the shoe plate 16 is within the normal range), the control device 5 ends the processing in the current processing cycle.

  On the other hand, when the determination result of STEP 3 is positive (when the rotation speed Np of the shoe plate 16 deviates from the normal range), the control device 5 determines that the rotation speed Np of the shoe plate 16 is normal at STEP 4. The value of the deviation number Md indicating the number of deviations from the range is counted up. The value of the number of deviations Md is stored and held in a non-volatile memory (not shown) while the hydraulic device A is stopped (when the construction machine equipped with the hydraulic device A is stopped).

  Next, in STEP 5, the control device 5 determines whether or not the number of departures Md has exceeded a predetermined threshold value TH1 set in advance.

  When this determination result is negative (when Md ≦ TH1), the control device 5 ends the processing in the current processing cycle.

  On the other hand, a situation where the determination result of STEP 5 is affirmative (a situation where Md> TH1) is caused by the occurrence of galling or the like between the shoe plate 16 and the swash plate 15 or the shoe 14. 16 and the swash plate 15 or the shoe 14 has a sliding abnormality, or it can be considered that the possibility is high.

  Even if it is possible to perform the required operation of the hydraulic pump 1, this situation is likely to cause a failure or malfunction of the hydraulic pump 1 over time.

  Therefore, when the determination result in STEP 5 is affirmative, the control device 5 generates a notification output indicating that the abnormality of the hydraulic pump 1 has occurred, assuming that the abnormality of the hydraulic pump 1 has occurred. As the notification output, for example, an audible notification output such as a buzzer sound or sound output, or a visual notification output such as lighting of an alarm lamp or display of alarm contents can be adopted.

  In the present embodiment, the abnormality detection process of the control device 5 is executed as described above. Thus, even in a situation where the required operation of the hydraulic pump 1 can be performed, due to the occurrence of galling between the shoe plate 16 and the swash plate 15 or the shoe 14, When a sliding abnormality with the swash plate 15 or the shoe 14 occurs, the occurrence of the abnormality is detected, and the occurrence of the abnormality is notified to the operator of the construction machine on which the hydraulic device A is mounted. Can do. As a result, the operator of the construction machine can be urged to check the hydraulic pump 1 before the failure or malfunction of the hydraulic pump 1 actually occurs.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIG. Note that this embodiment is different from the first embodiment only in a part of the configuration for detecting the occurrence of abnormality of the hydraulic pump 1. For this reason, the description of the present embodiment will be focused on matters that are different from the first embodiment, and the description of the same matters as the first embodiment will be omitted.

  Referring to FIG. 6, in this embodiment, instead of the rotation detection sensors 20a and 20b described in the first embodiment, a single rotation detection for detecting the rotation speed Np of the shoe plate 16 of the hydraulic pump 1 is performed. The sensor 20 c is fixed to the swash plate 15 via a bracket 21 so that the sensor 20 c can tilt integrally with the swash plate 15 in a state of facing the outer periphery of the shoe plate 16. The rotation detection sensor 20c is the same type of sensor as the rotation detection sensors 20a and 20b in the first embodiment, and corresponds to a rotation state detection unit in the present invention.

  Thereby, in the present embodiment, the rotation speed Np of the shoe plate 16 can be detected by the detection signal of the single rotation detection sensor 20c in an arbitrary tilt state of the swash plate 15 of the hydraulic pump 1. Yes.

  Then, in the abnormality detection process of the control device 5 in the present embodiment, the control device 5 uses the detection signal from the rotation detection sensor 20c in STEP 2 in any of the first operation state and the second operation state. The detected value of the rotational speed Np of the shoe plate 16 is acquired.

  The present embodiment is the same as the first embodiment except for the matters described above.

  This embodiment can achieve the same effects as those of the first embodiment. In addition, as a specific operation state for detecting occurrence of an abnormality in the hydraulic pump 1, an operation state other than the first operation state and the second operation state can be employed.

[Third Embodiment]
Next, a third embodiment of the present invention will be described with reference to FIG. Note that this embodiment is different from the first embodiment or the second embodiment only in a part of the abnormality detection process by the control device 5. For this reason, the description of the present embodiment will be focused on matters that are different from the first embodiment or the second embodiment, and description of the same matters as those of the first embodiment or the second embodiment will be omitted.

  In the present embodiment, the control device 5 executes the processing shown in the flowchart of FIG. 7 at a predetermined processing cycle during the operation of the hydraulic device A (during the operation in which the engine 2 is activated).

  In this case, the processing of STEP1 to STEP4 is the same as that of the first embodiment, and the processing of STEP5a is executed after STEP4. Here, in the present embodiment, the control device 5 repeats counting a predetermined set time (set value of the time width) from the start of operation of the hydraulic device A, and sets the set time (set time). Whether or not an abnormality has occurred in the hydraulic pump 1 is determined depending on whether or not the value of the number of deviations Md within each period exceeds a predetermined threshold TH2 set in advance.

  Further, the count value of the number of deviations Md is initialized to zero at the start of operation of the hydraulic device A and is reset to zero every time the set time has elapsed.

  Therefore, in STEP 5a, the control device 5 determines whether or not the value of the number of deviations Md within the set time period exceeds a predetermined threshold value TH2. Then, when the determination result of STEP 5a is affirmative (when Md> TH2), the control device 5 performs the processing of STEP 6 (processing for generating a notification output indicating that an abnormality of the hydraulic pump 1 has occurred). Execute.

  If the determination result in STEP 1 or 3 or 5a is negative, the control device 5 determines in STEP 5b whether the set time has elapsed. Then, when the determination result of STEP 5b is negative, the control device 5 ends the process of the current processing cycle, and when the determination result is affirmative, the value of the number of deviations Md is set to zero. After resetting, the processing in the current processing cycle is terminated. Thereby, the value of the number of deviations Md within the set time is obtained by the processing of STEP4.

  The present embodiment is the same as the first embodiment or the second embodiment except for the matters described above.

  According to this embodiment, the occurrence of an abnormality in the hydraulic pump 1 can be detected in a situation where the rotational speed Np of the shoe plate 16 deviates from the normal range frequently or continuously. .

  On the other hand, in the situation where the rotational speed Np of the shoe plate 16 deviates from the normal range only temporarily, it is possible to suppress the occurrence of the abnormality of the hydraulic pump 1.

  In each of the embodiments described above, the occurrence of an abnormality in the hydraulic pump 1 is detected based on whether or not the detected value of the rotational speed Np (rotational speed) of the shoe plate 16 deviates from the normal range. However, it is also possible to detect the occurrence of an abnormality in the hydraulic pump 1 based on, for example, a change in the rotational speed Np of the shoe plate 16 (a change amount per unit time or a change pattern).

  It is also possible to detect the occurrence of an abnormality in the hydraulic pump 1 based on both the detected value of the rotational speed Np of the shoe plate 16 and its change.

  Further, the abnormality detection process for detecting the occurrence of abnormality of the hydraulic pump 1 is executed only in one of the first operation state and the second operation state, or the abnormality detection process is executed in another operation state. It is also possible to do.

  Further, for example, the time duration of the state in which the rotational speed Np of the shoe plate 16 or the change thereof can be regarded as abnormal is counted, and when the duration exceeds a predetermined value, the occurrence of the abnormality of the hydraulic pump 1 is detected. Is also possible.

  Further, for example, when the rotational speed Np of the shoe plate 16 or the change thereof deviates greatly from the normal range by a predetermined amount or more, the occurrence of the abnormality of the hydraulic pump 1 may be detected immediately.

  Moreover, in each said embodiment, the case where the hydraulic rotary machine was a hydraulic pump was demonstrated as an example. However, the hydraulic rotating machine targeted by the present invention is not limited to a hydraulic pump, and may be a hydraulic motor. Alternatively, the present invention can also be applied to a hydraulic rotating machine (pump or motor) that uses a liquid (for example, water) other than hydraulic oil.

  The hydraulic rotating machine is not limited to a variable capacity type, but may be a constant capacity type in which the inclined state of the swash plate is kept constant.

  Further, the hydraulic rotating machine may be used for devices other than construction machines.

  DESCRIPTION OF SYMBOLS 1 ... Hydraulic pump (hydraulic rotary machine), 5 ... Control apparatus (abnormality detection processing part), 11 ... Rotary shaft, 12 ... Cylinder block, 13 ... Piston, 14 ... Shoe, 15 ... Swash plate, 16 ... Shoe plate, 20a, 20b, 20c... Rotation detection sensor (rotation state detection unit).

Claims (6)

A piston slidably attached to a cylinder block rotatable integrally with the rotary shaft; a shoe attached to the tip of the piston; a swash plate disposed on the tip of the piston; the shoe and An abnormality detection device for a hydraulic rotating machine comprising the shoe and a shoe plate interposed between the swash plate so as to be able to rotate with the rotation of the rotation shaft while being in sliding contact with the swash plate,
A rotation state detection unit for detecting a rotation state of the shoe plate;
An abnormality of the hydraulic rotating machine, comprising: an abnormality detection processing unit that detects an occurrence of an abnormality of the hydraulic rotating machine based on a rotation state of the shoe plate indicated by an output of the rotation state detecting unit. Detection device. In the abnormality detection apparatus of the hydraulic rotating machine according to claim 1,
The abnormality detection processing unit is configured to detect occurrence of an abnormality of the hydraulic rotating machine based on a detection value of a rotation speed of the shoe plate indicated by an output of the rotation state detection unit. An abnormality detection device for a hydraulic rotating machine. In the abnormality detection apparatus of the hydraulic rotating machine according to claim 2,
The abnormality detection processing unit is configured to detect an abnormality of the hydraulic rotating machine based on whether or not the detected value of the rotation speed of the shoe plate deviates from a normal range set according to the rotation speed of the rotation shaft. An abnormality detection device for a hydraulic rotating machine, characterized by being configured to detect occurrence. In the abnormality detection apparatus of the hydraulic rotating machine according to any one of claims 1 to 3,
The abnormality detection processing unit is configured to detect occurrence of an abnormality of the hydraulic rotating machine on the condition that the operating state of the hydraulic rotating machine is a predetermined predetermined operating state. An abnormality detection apparatus for a hydraulic rotating machine. In the abnormality detection apparatus of the hydraulic rotating machine according to claim 4,
The hydraulic rotating machine is a variable displacement pump capable of changing an inclination angle of the swash plate,
The abnormality detection device for a hydraulic rotating machine, wherein the predetermined operation state is an operation state in which an inclination angle of the swash plate is maintained at a constant inclination angle. In the abnormality detection apparatus of the hydraulic rotating machine according to claim 4,
The hydraulic rotary machine is a variable displacement hydraulic pump mounted on a construction machine and capable of changing the inclination angle of the swash plate,
The predetermined operation state includes an operation state in which the rotation angle of the hydraulic pump is rotationally driven by an engine in an idling operation state, and the inclination angle of the swash plate is kept at a minimum inclination angle, and the inclination angle of the swash plate is maximized. An abnormality detection device for a hydraulic rotating machine, comprising: at least one operation state of an operation state in which hydraulic oil is supplied from a hydraulic pump to a hydraulic actuator while maintaining an inclination angle of