JP2009236752A - Mounted load measurement device and mounted load measurement method of wheel loader - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wheel loader for automatically identifying operation similar to loading operation and accurately measuring the mounted load. <P>SOLUTION: The wheel loader 2 is provided with the mounted load measurement device 1. The device 1 detects the load to be mounted stored in a bucket 5 (1C) based on the differential pressure (1A) between the head pressure and bottom pressure of a boom cylinder 6 and the angle (1B) of a boom 4. An operator presets one or more integration conditions (1E) based on the boom angle and bucket angle, or the sampling time of the load measurement. Only when the set integration conditions are established, an integrating section 1F integrates the detected load and updates the integrated load (1G). Thus, for example, work of loosening feed and work of loading the feed on a track are identified automatically, and the mounted load can be accurately measured. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a loaded load measuring device and a loaded load measuring method for a wheel loader.

An apparatus for measuring the weight (loading load) of a load loaded on a dump truck by a wheel loader is known (Patent Document 1, Patent Document 2, Patent Document 3). For example, in the prior art described in the first document (Patent Document 1), the differential pressure of the hydraulic cylinder is sampled a plurality of times as the boom angle increases, and the load on the bucket is calculated for each sampling. And in this prior art, the total weight of the load loaded with the bucket is detected by integrating | calculating the average value of the calculated load.
JP 2001-99701 A JP 2006-336390 A No. 6-736

  In the prior art, when the boom angle changes from the lower side to the upper side, it is determined that one loading operation is completed, and the average value of the loads calculated during this operation is integrated. Therefore, if a boom operation similar to the loading operation is included in the loading operation, the load is calculated corresponding to the similar boom operation, and an error occurs in the integrated load.

  For this reason, in the prior art disclosed in the first patent document, as shown in S8 of FIG. 3 and paragraph 0013, a cancel switch for canceling the calculated load is provided. Therefore, in the prior art, even when a boom operation similar to the normal loading operation is included in the work, the load calculated by the similar boom operation can be manually canceled, and the decrease in measurement accuracy is suppressed. can do.

  However, the operator of the wheel loader needs to manually cancel the load detected by mistake every time, which is inconvenient. Further, because of manual operation, there is a possibility that the manual cancellation operation may be forgotten due to a so-called inadvertent mistake.

  The present invention has been made paying attention to the above problems, and an object of the present invention is to provide a load load measuring device and a load load measuring method for a wheel loader that can accurately measure the load and improve the usability. It is in.

  In order to solve the above-described problem, a load measuring device for measuring a load of a wheel loader according to the present invention, which includes a boom having a bucket rotatably provided at a tip and a boom cylinder that rotates the boom. Are a pressure detector that detects the pressure of the boom cylinder, a boom angle detector that detects the angle of the boom, a pressure of the boom cylinder that is detected by the pressure detector, and a boom angle that is detected by the boom angle detector. Based on the load detection unit that detects the load of the bucket a plurality of times during a predetermined period when the boom is rising, a first storage unit that temporarily stores each load detected by the load detection unit, and a first storage unit An integration condition setting unit for setting an integration condition for determining whether or not to update the integrated load based on each stored load, and an integration condition set by the integration condition setting unit are satisfied. If it is, based on each load stored in the first storage unit includes an integrating portion for updating the accumulated loads to be stored in the second storage unit.

  The integration unit can delete each load stored in the first storage unit when the integration condition is not satisfied.

  The integration condition set by the integration condition setting unit is (1) when the boom angle enters a first angle range that is preset within a predetermined period, and (2) the bucket angle is preset within a predetermined period. (3) when the predetermined period is equal to or longer than the preset first period and no load is detected within the second period before and after the predetermined period. It may be one or more.

  In accordance with another aspect of the present invention, a loading load measuring method for measuring a loading load of a wheel loader provided with a boom rotatably provided at a tip and a boom cylinder for rotating the boom is provided by: Based on the pressure of the boom cylinder and the angle of the boom until it is determined that the predetermined time has been reached and the end of the predetermined time when the predetermined time has come. And detecting the load of the bucket a plurality of times, temporarily storing each detected load in the first storage unit, and an integration for determining whether to update the integrated load based on each load A step of determining whether or not the condition is satisfied, and a product stored in the second storage unit based on each load stored in the first storage unit when it is determined that the integration condition is satisfied Executing a step of updating the load, respectively.

  According to the present invention, when a preset integration condition is satisfied, the integrated load is updated based on the detected load. Therefore, an operation similar to a normal loading operation is included in the work content of the wheel loader. Even in such a case, it is possible to automatically prevent the load detected by the similar operation from being added to the integrated load. Thereby, usability can be improved, maintaining measurement accuracy.

  According to the present invention, when the accumulation condition is not satisfied, each load stored in the first storage unit is erased. Therefore, it is possible to prevent a useless load from being stored in the first storage unit, and the first storage Can be used efficiently.

  According to the present invention, in order to prepare integration conditions set by paying attention to the boom angle, bucket angle, and predetermined period, one or more appropriate integration conditions can be set according to the work content of the wheel loader. it can.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the present embodiment, as described below, when the bucket load is automatically measured according to the boom operation, the integrated load is automatically prevented from being updated by a similar operation different from the loading operation. Examples of the loading operation include an operation for loading feed on a loading platform such as a dump truck. Examples of the similar operation include an operation of loosening the hardened feed with a bucket. FIG. 1 is a conceptual diagram showing the entirety of the present embodiment. FIG. 1 shows an outline of the present invention for understanding and implementing the present invention, and the scope of the present invention is not limited to the configuration shown in FIG.

  The loaded load measuring device 1 is provided in the wheel loader 2. Although details will be made clear in an embodiment described later, the wheel loader 2 includes a vehicle body 3, a boom 4 provided on the front side of the vehicle body 3, a bucket 5 provided on the tip side of the boom 4, and the boom 4 in the vertical direction. A boom cylinder 6 and the like are provided for rotation.

  The loaded load measuring device 1 (hereinafter may be abbreviated as the measuring device 1) is a device that measures the total load of the load loaded by the bucket 5. The measuring device 1 includes, for example, a differential pressure detection unit 1A, a boom angle detection unit 1B, a load detection unit 1C, a first storage unit 1D, an integration condition setting unit 1E, an integration unit 1F, and a second storage unit. 1G and a display unit 1H.

  The differential pressure detection unit 1A is a circuit for detecting a difference between the head pressure and the bottom pressure of the boom cylinder 6. The boom angle detection unit 1B is a circuit for detecting the angle of the boom 4. Although simplified in FIG. 1, a bucket angle detection unit for detecting the angle of the bucket 5 may be provided.

  The load detection unit 1C detects the load of the load loaded in the bucket 5 a plurality of times during a predetermined period based on the differential pressure of the boom cylinder 6 and the boom angle. That is, the load detection unit 1C samples the differential pressure and the like a plurality of times within a predetermined period, and detects the load in each sampling. The detected load is stored in the first storage unit 1D.

  The integration condition setting unit 1E sets an integration condition for determining whether or not to update the integration load in the integration unit 1F. As the integration condition, for example, (1) when the boom angle detected in a predetermined period (sampling time) falls within a preset first angle range, (2) the bucket angle detected in the predetermined period is When entering the set second angle range, (3) when the predetermined period is not less than the first period set in advance and the load is not detected within the second period before and after the predetermined period. It can be set as follows.

  The accumulating unit 1F determines whether or not the accumulating condition is satisfied when a predetermined period in one loading operation ends. When the integration condition is satisfied, that is, when the integration condition is satisfied, the integration unit 1F updates the integrated load stored in the second storage unit 1G based on each load stored in the first storage unit 1D. Let For example, the integrating unit 1F calculates an average value of each load detected and stored in one loading operation, and adds this average load to the integrated load.

  The display unit 1H displays, for example, the currently detected load, the average value of each load, the accumulated load, and the accumulated condition. The operator can confirm the integration condition, the integration load, and the like based on the display content of the display unit 1H.

  According to the present embodiment configured as described above, for example, in the operation of loosening the fastened feed with the bucket 5 and loading the loosened feed on the dump truck, the load detected by the loosening operation is integrated. It is automatically prevented from being added to the load, and usability can be improved while maintaining measurement accuracy.

  Examples of the present invention will be described below. First, FIG. 2 is explanatory drawing which shows the operation | work process of the wheel loader 10 by a present Example. FIG. 2A shows the configuration of the work site. This work site includes, for example, a wheel loader 10, a dump truck 20, and a feed loading place 30. The configuration of the wheel loader 10 will be described later with reference to FIG. In the feed loading place 30, for example, a fastened feed 31 such as silage is accommodated.

  As shown in FIG. 2 (b), the operator loosens the feed 31 at the tip of the bucket 52 by rotating the boom 51 up and down. As shown in FIG. 2 (c), the operator scoops a part of the loosened feed 31A with the bucket 52 and moves backward.

  As shown in FIG. 2D, the operator lifts the boom 51 higher than the loading platform 21 of the dump truck 20 while approaching the dump truck 20. As shown in FIG. 2 (e), the operator throws the feed 31 </ b> A into the loading platform 21 of the dump truck 20 by tilting the bucket 52. After dropping the feed 31 </ b> A in the bucket 52 onto the loading platform 21, the operator moves backward and returns to the feed loading place 30.

  The operator repeats the process of loosening the feed, the process of scooping the loosened feed, and the process of loading the feed into the dump truck 20. The unwinding operation and the loading operation onto the dump truck 20 do not necessarily correspond one-on-one. This is because a large amount of feed can be loosened by one loosening operation.

  FIG. 3 is a side view of the wheel loader 10. The wheel loader 10 includes, for example, a vehicle body 11, a pair of left and right tires 12 provided on the front and rear sides of the vehicle body 11, a machine room 13 provided on the rear side of the vehicle body 11, a work machine 14 provided on the front side of the vehicle body 11, And a cab 15 provided at the center of the vehicle body 11.

  The vehicle body 11 includes a rear vehicle body 11C, a front vehicle body 11A, and a connecting portion 11B that connects the rear vehicle body 11C and the front vehicle body 11A.

  The machine room 13 houses an engine, a hydraulic pump, and the like. The work implement 14 includes, for example, a boom 51 that is rotatably provided so as to extend forward from the front vehicle body 11A, a bucket 52 that is rotatably provided at the tip of the boom 51, and the boom 51 in the vertical direction. A boom cylinder 53 for rotating and a bucket cylinder 54 for rotating the bucket 52 are provided.

  As described in FIG. 2, the operator approaches the dump truck 20 with the feed loaded in the bucket 52 and positions the bucket 52 above the loading platform 21. Then, the operator causes the feed in the bucket to drop onto the loading platform 21 by rotating the bucket 52 downward.

  FIG. 4 is a block diagram showing a detailed configuration of the loaded load measuring apparatus 1 shown in FIG. Hereinafter, it is also referred to as a measuring device 1. The measuring device 1 includes, for example, a control device 110, various sensors 120, and a display device 130.

  The sensors 120 are a collective term for detectors (sensors) 121 to 124 and a switch 125 described later. The boom angle detector 121 includes, for example, a potentiometer and detects the angle of the boom 51 and outputs an electrical signal. The bucket angle detector 122 is also configured as a potentiometer, for example, and detects the angle of the bucket 52 and outputs an electrical signal.

  The head pressure detector 123 detects the head pressure of the boom cylinder 53 and outputs an electric signal. The bottom pressure detector 124 detects the bottom pressure of the boom cylinder 53 and outputs an electric signal. The setting switch 125 is a manual switch for setting a load integration condition (sometimes simply referred to as an integration condition).

  The display device 130 includes, for example, an integrated load display unit 131, a load display unit 132, and an integrated condition display unit 133. The display device 130 can individually display the average load at the time of each sampling detected during work, the integrated value of the load (integrated load), and the conditions for integrating the load. An individual liquid crystal display or the like may be prepared for each of the display units 131 to 132, or a load, an integrated load, or the like may be individually displayed on a single liquid crystal display panel.

  The control device 110 includes, for example, an arithmetic processing device 111 (hereinafter, CPU 111), a nonvolatile memory 112, and an input circuit 113. The CPU 111 includes an internal memory 111A (cache memory 111A) and a timer 111B. The internal memory 111A stores a load D1 at the time of each sampling.

  The nonvolatile memory 112 is composed of, for example, a flash memory device, and stores an accumulated load D2, a characteristic diagram T1, programs for realizing the functions 210 to 230, and the like. The characteristic diagram T1 will be described later together with FIG.

  The load detection unit 210 has a function of detecting the load of the bucket 52 based on the differential pressure of the boom cylinder 53 while the boom 51 is rising. The integration condition setting unit 220 is a function for setting a condition for controlling whether or not the load is integrated. The integration unit 230 is a function that updates the value of the integrated load by reflecting the detected load in the integrated load only when the integration condition is satisfied.

  The input circuit 113 is an interface circuit for receiving electrical signals from various sensors 120.

  FIG. 5 is an explanatory diagram schematically showing the angle of the boom 51 in the initial state where the loading operation is started. A case where a line A <b> 1-A <b> 1 connecting the rotation fulcrum 51 </ b> A of the boom 51 and the rotation fulcrum 52 </ b> A of the bucket 52 is parallel to the ground (horizontal plane) H is used as a reference.

  In the present embodiment, the position where the boom 51 is rotated by θ below the reference line A1-A1 is detected as the initial position for starting loading. The value of θ is, for example, 10 degrees. However, this value is an example and does not limit the present invention.

  Loading is performed when the line A2-A2 connecting the rotation fulcrum 51A of the boom 51 and the rotation fulcrum 52A of the bucket 52 is located above the position rotated counterclockwise by θ from the reference line A1-A1. It can be determined that the operation has started. The definition shown in FIG. 5 is an example, and the present invention is not limited to this.

  That is, in the present embodiment, it is determined that the loading operation is started when the boom 51 rotates in the clockwise direction with respect to the line A2-A2. The end of the loading operation is detected when the rotation of the boom 51 is stopped. However, even when the boom 51 rotates from below to above, there is no guarantee that the operation always indicates a loading operation. This is because the boom 51 may be moved up and down to loosen the loading object as described above.

  FIG. 6 is an explanatory diagram showing the configuration of the characteristic diagram T1. The characteristic chart T1 shows the relationship between the boom angle θ and the cylinder differential pressure ΔP for each loading rate of the bucket 52. FIG. 6 shows characteristic lines when the standard load is not loaded at all (0%), when only half is loaded (50%), and when the full load is loaded (100%). Therefore, if the differential pressure of the boom cylinder 53 and the boom angle θ are obtained, the bucket load at that time can be detected.

  FIG. 7 shows a process for setting the loading condition. For example, the operator can cause the display device 130 to display the menu screen G1 for inputting the loading conditions by operating the setting switch 125 (S10).

  On the menu screen G1, for example, a plurality of menus for setting different loading conditions are displayed. The operator selects one of the plurality of menus (S11) and sets the loading conditions (S12). The control device 110 stores the set loading condition in the integration condition setting unit 220 in the nonvolatile memory 112 (S13). The control device 110 determines whether or not the setting of the loading condition has been completed (S14). If the setting has not been completed (S14: NO), the control device 110 returns to S11. Therefore, the operator can set a plurality of different integration conditions.

  As shown on the lower side of FIG. 7, for example, a first integration condition menu G2, a second integration condition menu G3, and a third integration condition menu G4 are displayed on the menu screen G1, respectively. Each integration condition can be used in combination, or only one of the integration conditions can be used.

  FIG. 8A shows an example of a screen when the first integration condition menu G2 is selected. The first integration condition is that the integration condition is that the angle of the boom 51 is within a preset effective boom angle range within a period (predetermined period) during which the bucket load is sampled. The operator sets a lower limit value of the boom angle. The current angle of the boom 51 can be displayed on the screen.

  In the lower limit value of the boom angle, a threshold value for distinguishing between the loading operation on the dump truck 20 and the similar operation (operation for loosening feed in the present embodiment) is set.

  A specific example will be described. For example, in the operation of loosening the feed, the operator rotates the boom 51 from the ground to a height of 2.5 meters. In contrast, in the operation of loading feed into the dump truck 20, the operator rotates the boom 51 from the ground to a height of 3 meters.

  That is, it is assumed that the height of the solidified feed is about 2.5 meters and the height of the upper part of the loading platform 21 of the dump truck 20 is about 3 meters. In this case, the operator sets the boom angle when the height of the boom 51 is 3 meters as the lower limit value.

  Therefore, in the case of the first integration condition, when the maximum value of the boom angle exceeds the lower limit at the end of the bucket load sampling, it is determined that the feed is loaded on the loading platform 21. it can.

  For example, if the first flag indicating that the first integration condition is satisfied is set when the boom angle exceeds the lower limit value, based on the set state of the first flag after completion of bucket load sampling. It can be determined whether or not the first integration condition is satisfied. Alternatively, the boom angle at the time of sampling the bucket load can be stored, and it can be determined whether or not the boom angle has exceeded the lower limit value after the end of sampling.

  FIG. 8B is an example of a screen when the second integration condition menu G3 is selected. The second accumulation condition is that the angle of the bucket 52 is within a preset effective bucket angle range within the bucket load sampling time. The operator sets an upper limit value for the bucket angle. The current angle of the bucket 52 can also be displayed on the screen.

  For example, in order to drop the feed in the bucket 52 onto the loading platform 21 of the dump truck 20, it is necessary to rotate the bucket angle by −35 degrees or more. In this case, the operator sets −35 degrees as the upper limit value of the bucket angle.

  When the bucket angle is 0 degree when the bucket 52 is level with the ground, and the bucket 52 rotates counterclockwise (downward), the bucket angle becomes a negative value. When only the loosened feed is loosened by the bucket 52, it is not necessary to change the angle of the bucket 52 greatly. On the other hand, when dropping the feed above the loading platform 21, it is necessary to rotate the bucket 52 greatly downward. Therefore, by setting the bucket angle necessary for dropping the feed in the bucket 52 as the bucket angle upper limit value, it can be determined whether or not the loading operation has been performed.

  FIG. 8C is a screen example when the third integration condition menu G4 is selected. The third integration condition is when the bucket load sampling time is equal to or longer than a preset sampling time, and the bucket load is not detected within the time before and after the sampling time.

  In this embodiment, as shown in FIG. 8C, the sampling time value is set as 10 seconds. In a normal loading operation, the boom 51 rotates greatly from below to above, and the load on the bucket 52 is detected a plurality of times while the boom 51 rotates. Therefore, in the case of the loading operation, the boom rotation time (that is, the bucket load sampling time) is relatively long.

  On the other hand, in the case of the loosening operation, the boom 51 is moved up and down within a range smaller than the loading operation. Accordingly, in the case of the loosening operation, the bucket load sampling time is relatively short. Therefore, in this embodiment, the normal loading operation is determined when the set sampling time is exceeded and the bucket load is not detected before and after the sampling time.

  As described with reference to FIG. 2, in the normal loading operation, the operator pivots the boom 51 from the lower side to the upper side to scoop the feed, changes the direction, approaches the dump truck 20, and moves above the loading platform 21. The bucket 52 is rotated. When the boom 51 starts to rotate clockwise from A2-A2 in FIG. 5, sampling of the bucket load is started.

  Therefore, in the normal loading operation, the bucket load is not detected once the sampling is completed. That is, since the wheel loader 10 approaches the dump truck 20 with the bucket 52 being lifted high, the next load measurement is not performed until the second period elapses.

  On the other hand, in the case of the loosening operation, the operator reciprocates the boom 51 between the lower side and the upper side with a relatively short cycle. Therefore, in the case of the loosening work, the bucket load sampling is repeated at a relatively short interval.

  Therefore, in the third integration condition shown in FIG. 8C, when the bucket load sampling time is equal to or longer than the predetermined time and the bucket load is not detected within the time before and after the sampling time, it is normal. It is determined that this is a loading operation.

  FIG. 9 is a flowchart showing a process for measuring a load. The loaded load is the total weight loaded on the dump truck 20 by the wheel loader 10.

  The loaded load measuring device 1 determines whether or not a start condition for measuring the bucket load is satisfied (S20). As described in FIG. 5, when the boom 51 starts to rotate clockwise from the position of the A2-A2 line, the bucket load measurement start condition is satisfied (S20: YES).

  When the measurement start condition is satisfied, the measuring device 1 measures the bucket load based on the boom angle and the differential pressure of the boom cylinder 53, and stores the measurement result (D1) in the internal memory 111A (S21). The measuring device 1 determines whether or not an end condition for ending the bucket load measurement is satisfied (S22). The measuring device 1 ends the measurement of the bucket load when the rotation of the boom 51 is stopped (S22: YES). As described above, the measuring apparatus 1 repeatedly measures and stores the bucket load while the boom 51 rotates upward from below.

  The measuring apparatus 1 determines whether or not the bucket load sampling number is equal to or greater than a predetermined number (S23). When the number of measurement values of the bucket load obtained in S21 is less than the predetermined number (S23: NO), the measuring device 1 deletes the bucket load (sampling data) stored in the internal memory 111A (S24), and S20 Return to.

  The predetermined number is set as the minimum number of data necessary for calculating an accurate load. Therefore, when the bucket load measurement value obtained in S21 is less than the predetermined number (S23: NO), the measurement device 1 discards the measurement value accumulated in the internal memory 111A (S24) and repeats the measurement (S20). ).

  When the number of measurement values obtained in S21 is equal to or greater than a predetermined number (S23: YES), the measurement device 1 stores the measurement end time based on the value of the timer 111B (S25). The measurement end time is the time when the bucket load measurement (sampling) in S21 ends.

  The measuring device 1 reads the integration condition set by the operator from the nonvolatile memory 112 (S26), and determines whether or not the integration condition is satisfied (S27). Details of S27 will be described later with reference to FIG.

  When the integration condition is not satisfied (S27: NO), the measuring device 1 deletes the measurement value stored in the internal memory 111A (S28), and returns to S20. This is because the case where the integration condition is not satisfied (S27: NO) is a case where the bucket load is measured based on another operation other than the normal loading operation.

  When the integration condition is satisfied (S27: YES), the measuring device 1 calculates a load for integration based on the plurality of measurement values stored in the internal memory 111A (S29). For example, the measuring device 1 calculates an average value of each measurement value, and uses this average value as a load for integration.

  The measuring device 1 adds the integrated load to the integrated load (D2) stored in the nonvolatile memory 112, and updates the value of the integrated load (S30). Then, the measuring device 1 deletes each measured value stored in the internal memory 111A (S31), and determines whether or not to end the process (S32).

  When the loading load measurement process is completed (S32: YES), this process ends. When the load load measurement process is continued (S32: NO), the process returns to S20.

  FIG. 10 is a flowchart of a process for determining whether the integration condition is satisfied, which is indicated by S27 in FIG. Here, a case where all the three integration conditions described in FIG. 8 are set will be described.

  The measuring device 1 acquires the boom angle during the bucket load measurement period (during the sampling time) (S40), and determines whether the boom angle at the sampling time is within the effective boom angle range shown in FIG. Determine (S41).

  As described above, the configuration may be such that all boom angles and bucket angles during the sampling time are temporarily recorded, or a flag that indicates that the boom angles and bucket angles are within the valid range may be used.

  When the boom angle during the sampling time is within the effective range (S41: YES), the measuring apparatus 1 determines whether or not the bucket angle during the sampling time is within the effective bucket angle range shown in FIG. Is determined (S43).

  When the bucket angle during the sampling time is within the effective range (S43: YES), the measuring device 1 acquires the length of the sampling time (S44). The measuring device 1 determines whether or not the length of the sampling time is equal to or longer than a predetermined time set in advance (S45).

  When the sampling time is equal to or longer than the predetermined time (S45: YES), the measuring device 1 determines whether or not a load is detected within the time positions before and after the sampling time (S46).

  When the load is not detected within the time positions before and after the sampling time (S46: YES), the measuring device 1 determines that the integration condition is satisfied (S47). Accordingly, S27 in FIG. 9 is determined as “YES”.

  On the other hand, when it is determined as “NO” in any of S41, S43, S45, and S46, the measuring device 1 determines that the integration condition is not satisfied (S48). That is, when the boom angle during the sampling time is not within the effective boom angle range (S41: NO), or when the bucket angle during the sampling time is not within the effective bucket angle range (S43: NO), or the sampling time Is shorter than the first period (S45: NO), or when the load is measured within the second period before and after the sampling time (S46: NO). Thereby, S27 in FIG. 9 is determined as “NO”.

  As described above, when a plurality of integration conditions are set, the integrated load is updated with the measured load when all the integration conditions are satisfied. On the other hand, when any one of the integration conditions is not satisfied, the measured load is discarded from the internal memory 111A, and the integration load is not updated.

  As described above in detail, in the present embodiment, the load of the bucket 52 is sampled a plurality of times while the boom 51 is rotating, and is integrated with the sampled load only when a preset integration condition is satisfied. Update the load.

  Therefore, for example, even when an operation similar to a normal loading operation is included in a series of work contents such as an operation of loosening the feed and an operation of loading the loosened feed onto the dump truck 20. In addition, it is possible to automatically detect the loading operation and measure the loaded load, which improves usability.

  In this embodiment, different integration conditions can be set based on a plurality of viewpoints such as a boom angle, a bucket angle, and a sampling time. Therefore, it is possible to set an integration condition suitable for the work content.

In addition, this invention is not limited to each Example mentioned above. A person skilled in the art can make various additions and changes within the scope of the present invention. For example, although the case where three integration conditions are set is described, the present invention is not limited to this, and a configuration in which any one or two integration conditions are set may be used.
In the above-described embodiment, the case of determining whether or not the loading operation is performed from the three viewpoints of the boom angle, the bucket angle, and the sampling time has been described. However, other viewpoints (for example, vehicle speed, hydraulic pressure, etc.) ) May be combined.
Furthermore, in the said Example, although the operation | movement which loosens a feed was mentioned as an example as operation | movement similar to normal loading operation | movement, it was not restricted to this, Other similar operation | movement can also be identified.

Explanatory drawing which shows the whole outline | summary of a present Example. Explanatory drawing which shows work content. The side view of a wheel loader. The block diagram of a load measuring device. Explanatory drawing which shows the reference | standard of boom angle and the starting angle of load measurement. The characteristic view which shows the relationship between a boom angle, cylinder differential pressure | voltage, and a loading rate. The flowchart which sets the conditions for integrating | accumulating a load. Screen example showing how to set integration conditions. The flowchart of an integrated load measurement process. The flowchart which shows the detail of S21 in FIG.

Explanation of symbols

  1: Load measuring device, 1A: differential pressure detection unit, 1B: boom angle detection unit, 1C: load detection unit, 1D: first storage unit, 1E: integration condition setting unit, 1F: integration unit, 1G: second Storage unit, 1H: display unit, 2: wheel loader, 3: vehicle body, 4: boom, 5: bucket, 6: boom cylinder, 10: wheel loader, 11: vehicle body, 11A: front vehicle body, 11B: connecting unit, 11C: rear body, 12: tire, 13: machine room, 14: work machine, 15: cab, 20: dump truck, 21: loading platform, 30: feed loading place, 31: feed, 31A: loosened feed 51: Boom, 51A, 52A: Rotation fulcrum, 52: Bucket, 53: Boom cylinder, 54: Bucket cylinder, 100: Load load measuring device, 110: Control device, 111: Arithmetic processing device, 111A: Inside Memo , 111B: timer, 112: nonvolatile memory, 113: input circuit, 120: sensors, 121: boom angle detector, 122: bucket angle detector, 123: head pressure detector, 124: bottom pressure detector, 125 : Setting switch 130: Display device 131: Accumulated load display part 132: Load display part 133: Accumulation condition display part 210: Load detection part 220: Accumulation condition setting part 230: Accumulation part

Claims (4)

Measures the load of a wheel loader (2, 10) having a boom (4, 51) with a bucket (5, 52) rotatably provided at the tip and a boom cylinder (6, 53) for rotating the boom. Load capacity measuring device for
A pressure detector (1A, 123, 124) for detecting the pressure of the boom cylinder;
A boom angle detector (1B, 121) for detecting the angle of the boom;
Based on the pressure of the boom cylinder detected by the pressure detector and the angle of the boom detected by the boom angle detector, the load of the bucket (D1) during a predetermined period when the boom is rising ) Multiple times, and a load detector (1C, 210),
A first storage unit (1D, 111A) that temporarily stores the loads detected by the load detection unit;
An integration condition setting unit (1E, 220) for setting an integration condition for determining whether or not to update the integrated load (D2) based on each load stored in the first storage unit;
When the integration condition set by the integration condition setting unit is satisfied, the second storage unit (1G, 112) stores the load based on the loads stored in the first storage unit. An integration unit (1F, 230) for updating the integrated load;
A load load measuring device for a wheel loader, comprising:   The wheel loader load-load measuring device according to claim 1, wherein the integration unit deletes the loads stored in the first storage unit when the integration condition is not satisfied.   The integration condition set by the integration condition setting unit is (1) when the angle of the boom enters a preset first angle range within the predetermined period, and (2) within the predetermined period, When the angle falls within a preset second angle range, (3) the predetermined period is equal to or greater than the preset first period, and the load is applied within the second period before and after the predetermined period. The loaded load measuring device for a wheel loader according to any one of claims 1 and 2, wherein the load load is any one or more when not detected. Measurement of the load on a wheel loader (2, 10) having a boom (4, 51) provided with a bucket (5, 52) rotatably at the tip and a boom cylinder (6, 53) for rotating the boom. Load capacity measurement method for
Determining whether a predetermined time for measuring the load of the bucket has arrived (S20);
When the predetermined time has arrived, the load (D1) of the bucket is detected a plurality of times based on the pressure of the boom cylinder and the angle of the boom until it is determined that the predetermined time has ended. A step (S21) of temporarily storing the detected loads in the first storage unit (1D, 111A);
Determining whether or not an accumulation condition for determining whether or not to update the accumulated load based on each load is satisfied (S27);
When it is determined that the integration condition is satisfied, the integrated load (D2) stored in the second storage unit (1G, 112) is calculated based on the loads stored in the first storage unit. A step of updating (S30);
The load load load method of the wheel loader that performs each.

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