JP6753337B2 - Crane information presentation system and crane - Google Patents

Description

The present invention relates to an information presentation system for a crane.

Conventionally, a crane equipped with a multi-stage telescopic boom (so-called telescopic boom) is known. Each of the multi-stage telescopic booms has a plurality of boom bodies formed in a square tubular shape. For example, Patent Document 1 describes a one-stage boom body that can undulate with respect to the crane body, a two-stage boom body that can expand and contract with respect to the one-stage boom body, and a three-stage boom body that can expand and contract with respect to the two-stage boom body. A boom body and a crane with a boom having the boom body are disclosed. In this crane, the length (total length) of the boom can be changed according to the working mode. Specifically, in the crane mode having a large working radius, the insertion amount between the boom bodies is set to be relatively small. That is, in the crane mode, the total length of the boom is set to be relatively long. On the other hand, in the civil engineering mode in which the boom is required to have strength, the insertion amount between the boom bodies is set to be larger than that in the crane mode. That is, in the civil engineering mode, the total length of the boom is set shorter than the total length in the crane mode. In this way, by changing the insertion amount between the boom bodies according to the work mode, an appropriate total rated load according to the mode is set.

Japanese Unexamined Patent Publication No. 2004-911142

With the crane described in Patent Document 1, it is difficult to increase the durability of the boom without increasing the size and weight of the boom. Specifically, in the crane of Patent Document 1, in any mode, a repeated thrust reaction force is repeatedly pushed up from the rear end portion of each boom body to the upper surface portion of the boom body one step before the boom body during work. Works. More specifically, for each of the two work modes, the insertion amount of the two-stage boom body and the three-stage boom body, that is, the position of the rear end portion of the two-stage boom body and the position of the rear end portion of the three-stage boom body. There are also two action sites (sites where fatigue accumulates) where the push-up reaction force repeatedly acts from the rear end of each boom body to the upper surface of the boom body one step before the boom body. Limited. Therefore, in order to improve the durability of the boom, it is conceivable to increase the strength of the action site (increase the thickness, etc.). However, doing so entails an increase in size or weight of the boom.

An object of the present invention is to improve the durability (life) of a boom in a crane having a multi-stage telescopic boom without significantly increasing the size or weight.

As a result of diligent studies to solve the above problems, the present inventions adjust the insertion amount of each boom body to cause fatigue caused by the thrust reaction force repeatedly acting on the boom body in each boom body. It was conceived that the durability (life) of each boom body can be improved without significantly increasing the size or weight of the boom body by dispersing the accumulated parts. Then, it was conceived that the realization would be possible by creating fatigue accumulation information indicating the degree of fatigue accumulation in each part of each boom body and presenting it to the crane operator.

The present invention has been made from this point of view. Specifically, the present invention can move the crane main body, the one-stage boom body that is undulating and cylindrical with respect to the crane main body, and the first-stage boom body in the axial direction of the first boom body. A boom including a two-stage boom body formed in a tubular shape, an undulating cylinder that undulates the one-stage boom body with respect to the crane body, and expansion and contraction of the two-stage boom body with respect to the one-stage boom body. It is a system for presenting information about the boom of a crane including a two-stage hydraulic cylinder to be operated, and a push-up acting on the one-stage boom body from the rear end portion of the two-stage boom body among the one-stage boom bodies. The degree of accumulation of fatigue accumulated in the 1-step reaction force receiving portion, which is a part that receives the reaction force, and is the 1-step stress generated in the 1-step reaction force receiving portion due to the push-up reaction force and the 1-step reaction force. The relationship between the degree of fatigue accumulation calculated based on the number of times the push-up reaction force acts on the receiving portion and the SN diagram acquired in advance and the position of the rear end portion of the two-stage boom body is shown. Provided is an information presentation system for a crane, comprising a creating unit for creating fatigue accumulation information and a display unit for displaying the fatigue accumulation information and the position of the rear end portion of the two-stage boom body.

In this information presentation system, the degree of accumulation of fatigue in the 1-stage reaction force receiving portion that receives the push-up reaction force from the rear end portion of the 2-stage boom body and the position of the rear end portion of the 2-stage boom body are determined. Since it is displayed on the display unit, when adjusting the length of the boom, the position of the rear end of the two-stage boom body (of the two-stage boom body) so as to avoid the part of the one-stage boom body with a high degree of fatigue accumulation. The amount of insertion) can be adjusted. As a result, the fatigue accumulated in the one-stage boom body can be made uniform, so that the one-stage boom body can be compared with the case where the push-up reaction force repeatedly acts intensively only on a specific part of the one-stage boom body. Life is extended.

From the 1-step stress generated in the 1-step reaction force receiving portion and the SN diagram, the number of repetitions of the stress until the 1-step boom body breaks due to the action of the stress is obtained, and the above-mentioned action on the number of times is obtained. By calculating the number of times, the degree of stress accumulation until the first boom body is expected to break can be obtained.

In this case, the creating unit uses the fatigue accumulation information as the fatigue accumulation degree for each of a plurality of sections of the one-stage boom body, each of which has a predetermined length in the moving direction of the two-stage boom body. It is preferable to prepare the one showing.

In this way, the fatigue accumulated in a plurality of places in each section is added up and displayed as the fatigue of that section. Since this display is in line with the actual fracture mode, the fatigue accumulation information is a more effective guideline.

Further, the information presentation system of the crane further has a stress calculation unit for calculating the one-stage stress, and the stress calculation unit is theoretically based on the push-up reaction force acting on the one-stage reaction force receiving unit. Relationship between the theoretical stress value calculated in 1) and the measured stress value, which is a measured value of the actual stress generated in the 1-step reaction force receiving portion when the pushing-up reaction force acts on the 1-step reaction force receiving portion. It is preferable to calculate the one-step stress based on the stress concentration coefficient map obtained in advance and the push-up reaction force.

In this way, the one-step stress generated in the one-step reaction force receiving portion from the push-up reaction force can be easily obtained. Therefore, fatigue accumulation information is easily created as compared with the case of calculating the theoretical stress value, that is, the case of calculating the one-step stress from the push-up reaction force by simulation using a detailed analysis model.

Further, in the information presentation system of the crane, the action number calculation unit for calculating the action number of the push-up reaction force is further provided, and the action number calculation unit includes the length of the boom and the boom of the boom with respect to the crane main body. It is preferable to calculate the number of actions by accumulating the number of times that the actual load calculated based on the angle and the pressure of the undulating cylinder is from less than a predetermined value to more than or equal to the predetermined value.

In this way, the reaction force acting on the one-stage reaction force receiving portion due to vibration during work and less than the predetermined value, that is, noise that is substantially negligible with respect to the durability of the boom. Is reduced. Therefore, highly accurate fatigue accumulation information is created.

Further, in the information presentation system of the crane, the boom further includes a three-stage boom body that can move in the two-stage boom body in the axial direction of the two-stage boom body, and the three-stage boom body with respect to the two-stage boom body. From a state in which the three-stage hydraulic cylinder for expanding and contracting the step boom body and the state in which the two-stage boom body is allowed to extend so that the two-stage boom body extends with respect to the one-stage boom body, the two-stage boom body is changed to the two-stage boom body. On the other hand, it is preferable to further include a switching unit for switching to a state in which the expansion of the three-stage hydraulic cylinder is allowed so that the three-stage boom body extends.

In this way, in the boom including the three-stage boom body, the position (insertion amount) of the rear end portion of the two-stage boom body with respect to the one-stage boom body and the rear end portion of the three-stage boom body with respect to the two-stage boom body. The position of and both can be adjusted. Therefore, it is possible to flexibly adjust the total length of the boom while trying to equalize the fatigue accumulated in the one-stage boom body and the two-stage boom body.

In this case, the creating unit is a portion of the two-stage boom body that receives a push-up reaction force acting on the two-stage boom body from the rear end portion of the three-stage boom body as the fatigue accumulation information. The degree of accumulation of fatigue accumulated in the reaction force receiving portion, that is, the two-stage stress generated in the two-stage reaction force receiving portion due to the pushing-up reaction force and the pushing-up reaction force to the two-stage reaction force receiving portion. Information indicating the relationship between the fatigue accumulation degree calculated based on the number of actions and the SN diagram acquired in advance and the position of the rear end portion of the three-stage boom body is further created, and the display unit Further preferably displays the position of the rear end portion of the three-stage boom body.

By doing so, it is possible to avoid a portion having a high degree of fatigue accumulation in both the one-stage boom body and the two-stage boom body, so that the durability of the boom is further improved.

Further, the present invention includes a crane main body, a one-stage boom body that is undulating and cylindrical with respect to the crane main body, and a two-stage boom body that can be expanded and contracted with respect to the one-stage boom body. A two-stage hydraulic cylinder that expands and contracts the two-stage boom body with respect to the one-stage boom body, and an information presentation unit that presents information about the boom, and the information presentation unit is the one-stage boom body. Of these, the degree of accumulation of fatigue accumulated in the one-stage reaction force receiving portion, which is a portion that receives the push-up reaction force acting on the one-stage boom body from the rear end portion of the two-stage boom body, is the degree of accumulation of the fatigue, which is the push-up reaction force. Fatigue calculated based on the one-step stress generated in the one-step reaction force receiving portion, the number of times the push-up reaction force acts on the one-step reaction force receiving portion, and the SN diagram acquired in advance. A creation unit that creates fatigue accumulation information indicating the relationship between the degree of accumulation and the position of the rear end portion of the two-stage boom body, and the fatigue accumulation information and the position of the rear end portion of the two-stage boom body are displayed. Provided is a crane having a display and.

In this crane as well, the fatigue accumulated in the one-stage boom body can be made uniform, so compared to the case where the thrust reaction force repeatedly acts intensively only on a specific part of the one-stage boom body, one stage The life of the boom body is extended.

As described above, according to the present invention, in a crane having a multi-stage telescopic boom, the durability (life) of the boom can be improved without significantly increasing the size or weight.

It is a side view of the crane of one Embodiment of this invention. It is a figure which shows the structure of the expansion / contraction circuit of the boom of the crane shown in FIG. It is a block diagram of the information processing part of the crane shown in FIG. It is a SN diagram. It is a figure which shows the fatigue accumulation information. It is a figure which shows the modification of the fatigue accumulation information. It is a figure which shows the modification of the fatigue accumulation information. It is a figure which shows the modification of the fatigue accumulation information. It is a figure which shows the modification of the fatigue accumulation information.

A crane according to an embodiment of the present invention will be described with reference to FIGS. 1 to 5.

FIG. 1 shows the overall configuration of the crane of the present embodiment. This crane includes a swivel body 1 corresponding to a crane body, a lower traveling body 2 that supports the swivel body 1 so as to be swivel, a multi-stage telescopic boom (telescopic boom) 10, and a plurality of hydraulic cylinders 21 to 23. It is provided with an information processing unit 50 that processes various information.

The boom 10 has a plurality of boom bodies, each of which is formed in a square tubular shape. The boom bodies are telescopically fitted to each other. Specifically, the boom 10 has one stage so that the one-stage boom body 11 that can undulate with respect to the swivel body 1 and the one-stage boom body 11 can move relative to each other in the axial direction of the one-stage boom body 11. A two-stage boom body 12 fitted to the boom body 11 and a three-stage boom body 13 fitted to the two-stage boom body 12 so as to be relatively movable in the two-stage boom body 12 in the axial direction. have. The boom 10 is caused by the two-stage boom body 12 moving relative to the one-stage boom body 11 in the axial direction and the three-stage boom body 13 moving relative to the two-stage boom body 12 in the axial direction. As a whole expands and contracts in the axial direction.

The plurality of hydraulic cylinders include an undulating cylinder 21 that undulates the one-stage boom body 11, and a two-stage hydraulic cylinder 22 that expands and contracts so that the two-stage boom body 12 moves relative to the one-stage boom body 11 in the axial direction. And a three-stage hydraulic cylinder 23 that expands and contracts so as to move the three-stage boom body 13 relative to the two-stage boom body 12 in the axial direction. The two-stage hydraulic cylinder 22 is attached to the one-stage boom body 11 and the two-stage boom body 12 so as to straddle the one-stage boom body 11 and the two-stage boom body 12. The three-stage hydraulic cylinder 23 is attached to the two-stage boom body 12 and the three-stage boom body 13 so as to straddle the two-stage boom body 12 and the three-stage boom body 13. The extension amount of the two-stage boom body 12 from the one-stage boom body 11 is adjusted by the two-stage hydraulic cylinder 22. Similarly, the extension amount of the 3-stage boom body 13 from the 2-stage boom body 12 is adjusted by the 3-stage hydraulic cylinder 23.

Specifically, the drive circuits of the two-stage hydraulic cylinder 22 and the three-stage hydraulic cylinder 23 will be described with reference to FIG. As shown in FIG. 2, in this drive circuit, in the oil passage connecting the hydraulic pump 31 and the hydraulic cylinders 22 and 23, the oil passage is provided in order to control the expansion and contraction of the hydraulic cylinders 22 and 23. A switchable control valve 32 is provided. The control valve 32 has a neutral position a for stopping refueling from the hydraulic pump 31 to the hydraulic cylinders 22 and 23, an extension position b for extending the two-stage hydraulic cylinder 22 or the three-stage hydraulic cylinder 23, and two stages. It is possible to switch between the contraction position C for contracting the hydraulic cylinder 22 for three stages or the hydraulic cylinder 23 for three stages. The control valve 32 is switched by the remote control valve 33.

A two-stage three-stage switching valve 36 is provided between the control valve 32 and the extension-side oil passages 34 and 35 of the hydraulic cylinders 22 and 23. The two-stage three-stage switching valve 36 has a pilot valve 37 and a control valve (solenoid valve) 38. The pilot valve 37 switches between a two-stage expansion / contraction position a that allows expansion and contraction of the two-stage hydraulic cylinder 22 and a three-stage expansion / contraction position b that allows expansion and contraction of the three-stage hydraulic cylinder 23. The control valve 38 switches the pilot valve 37 to the two-stage expansion / contraction position a or the three-stage expansion / contraction position b. The switching of the control valve 38 is performed based on a signal from the controller 52, which will be described later. For example, at the start of extension of the boom 10, the pilot valve 37 is set to the two-stage expansion / contraction position a so that the extension of the two-stage hydraulic cylinder 22 is allowed, and then the extension of the three-stage hydraulic cylinder 23 is allowed. The pilot valve 37 is switched to the three-stage telescopic position b. On the contrary, when the boom 10 contracts, the pilot valve 37 is set to the three-stage expansion / contraction position b so that the contraction of the three-stage hydraulic cylinder 23 is allowed, and then the contraction of the two-stage hydraulic cylinder 22 is allowed. The pilot valve 37 is switched to the two-stage expansion / contraction position a.

An extension stop valve (solenoid valve) 40 controlled by the controller 52 is provided on the extension side pilot line 39 of the remote control valve 33. The extension stop valve 40 has an opening position a for communicating the extension side oil passages 34 and 35 with the extension side pilot line 39 so that the extension of the hydraulic cylinders 22 and 23 is allowed, and the extension position a of the hydraulic cylinders 22 and 23. It is switched to a shutoff position (b) that cuts off the extension side oil passages 34 and 35 from the extension side pilot line 39 so that the extension is prohibited. The switching of the extension stop valve 40 is performed based on the signal from the controller 52.

Further, a relief valve 41 is connected to the discharge oil passage of the hydraulic pump 31, and an overload automatic stop valve 43 is provided on the tank line 42 connecting the spring-side pressure port of the relief valve 41 and the tank T. The overload automatic stop valve 43 is switched between an opening position (b) for opening the tank line 42 and a shutoff position (a) for shutting off the tank line 42. The overload automatic stop valve 43 is in the shutoff position a except when the overload is applied, and is switched to the open position b when the overload is applied. The switching of the overload automatic stop valve 43 is performed based on the signal from the controller 52. The overload automatic stop valve 43 opens the tank line 42 and enables the relief valve 41 to unload by being switched to the opening position b. The operation of the boom 10 is stopped by this unloading action.

This crane can be switched between a crane mode in which normal crane operation is possible and a basic mode in which civil engineering work can be performed. The crane mode is a mode in which the suspended load is raised and lowered while the total length (working radius) of the boom 10 is relatively large. In this crane mode, the two-stage boom body 12 is usually extended to the maximum extension state, and the desired boom length is obtained by adjusting the extension amount of the three-stage boom body 13. The basic mode is a mode in which work is performed with a boom length shorter than the boom length in the crane mode. In this basic mode, for example, an attachment for civil engineering work such as a hammag lab bucket or a clam shell bucket is attached to the boom 10, and the excavation work is repeated in a short cycle time and carried out for a long time.

When this crane is operated in the basic mode, a push-up reaction force repeatedly acts from the rear end of the two-stage boom body 12 to the upper surface of the one-stage boom body 11, and 2 from the rear end of the three-stage boom body 13. The push-up reaction force repeatedly acts on the upper surface of the step boom body 12. As a result, the 1-stage reaction force receiving portion, which is a portion that receives the push-up reaction force from the rear end portion of the 2-stage boom body 12 of the 1-stage boom body 11, and the 3-stage boom body 13 of the 2-stage boom body 12 Fatigue accumulates in the two-stage reaction force receiving portion, which is a portion that receives the push-up reaction force from the rear end portion. The crane of the present embodiment creates fatigue accumulation information indicating the relationship between the degree of accumulation of fatigue accumulated in each boom body and the position of the rear end portion of each boom body, and displays the information on a monitor 53 corresponding to a display unit. It is possible to display. The monitor 53 is provided in the cabin 3 (see FIG. 1) provided in the swivel body 1.

Hereinafter, the information processing unit 50 that creates the fatigue accumulation information will be described with reference to FIG. The information processing unit 50 includes a transmission unit 51 that transmits various signals and information, and a controller 52 that includes a creation unit R that creates the fatigue accumulation information by processing the signals or information received from the transmission unit 51. .. Normally, the controller 52 is installed in the cabin 3.

The transmission unit 51 includes a two-stage three-stage changeover switch 51a corresponding to a changeover unit, a mode changeover switch 51b, a first boom length meter 51c, a second boom length meter 51d, a boom angle meter 51e, and pressure. It has a detector 51f, a stress concentration coefficient map 51g, and an SN diagram 51h.

The two-stage three-stage changeover switch 51a is a switch that switches between a state in which the two-stage boom body 12 can be expanded and contracted and a state in which the three-stage boom body 13 can be expanded and contracted in response to an operator's operation. Specifically, the two-stage three-stage changeover switch 51a determines which state is selected from the state in which the two-stage boom body 12 can be expanded and contracted and the state in which the three-stage boom body 13 can be expanded and contracted. The indicated signal is transmitted to the controller 52.

The mode changeover switch 51b is a switch that switches between the crane mode and the basic mode in response to an operator's operation. The mode changeover switch 51b transmits a signal indicating which of the crane mode and the basic mode is selected to the controller 52.

The first boom length meter 51c detects the length between the base end portion of the one-stage boom body 11 and the tip end portion of the three-stage boom body 13, and transmits the detected value to the controller 52.

The second boom length meter 51d detects the length between the base end portion of the first-stage boom body 11 and the tip end portion of the two-stage boom body 12, and transmits the detected value to the controller 52.

Here, each length meter includes a plurality of wire reels provided on the outer surface of the one-stage boom body 11. Each wire reel is connected to a portion near the tip of the two-stage boom body 12 and a portion near the tip of the three-stage boom body 13. The length of the wire coming in and out of the reel is measured according to the expansion and contraction of the boom bodies 12 and 13 of each stage. As a result, the expansion / contraction length (or insertion amount) of each stage boom body 12 and 13 is measured. The measuring method of the length meter is not limited to the above, and a method of measuring the expansion / contraction state of the hydraulic cylinders 22 and 23 for each stage may be used.

The boom angle meter 51e detects the angle of the boom 10 and transmits the detected value to the controller 52.

The pressure detector 51f detects the head pressure and the rod pressure of the undulating cylinder 21 and transmits the detected values to the controller 52.

The stress concentration coefficient map 51g is a pre-acquired map showing the relationship (ratio) between the theoretical stress value and the measured stress value. The theoretical stress value is a stress value theoretically calculated based on each push-up reaction force acting on the one-stage reaction force receiving portion and the two-stage reaction force receiving portion. Specifically, the theoretical stress value is the value of the tensile stress generated on the upper surface of each boom body due to the theoretically calculated push-up reaction force for each boom body insertion amount and load factor. The measured stress value is the value of the tensile stress measured based on the value of the strain gauge when the thrust reaction force actually acts on each boom body. A strain gauge is provided on each boom body at the test stage.

FIG. 51h is a graph showing the relationship between the stress amplitude σ and the number of repetitions N until fracture. FIG. 4 shows the SN diagram 51h.

The controller 52 includes a mode determination unit A, a maximum extension state determination unit B, each boom body insertion amount calculation unit C, a rated total load table selection unit D, each boom body length calculation unit E, and a boom angle calculation. Unit F, working radius calculation unit G, pressure calculation unit H, actual load calculation unit I, total rated load calculation unit J, push-up reaction force calculation unit K, comparison unit L, and stress calculation unit M. , A fatigue degree calculation unit N, a lifting presence / absence determination unit O, a fatigue accumulation degree calculation unit P, a switching determination unit Q, and the creation unit R.

The mode determination unit A determines the selected mode based on the signal received from the mode changeover switch 51a, and outputs a signal indicating the mode. The mode discriminating unit A outputs a mode switching signal only when the length of the three-stage boom body 13 calculated based on the signals received from the length gauges 51c and 51d is the shortest.

The maximum extension state determination unit B determines whether or not the two-stage boom body 12 and the three-stage boom body 13 are in the maximum extension state set according to each mode. The length of the two-stage boom body 12 and the length of the three-stage boom body 13 are calculated based on the detected values of the total lengths 51c and 51d. The length of the maximum extension state of each boom body in the basic mode is set shorter than the length of the maximum extension state of each boom body in the crane mode. When it is determined that the two-stage boom body 12 is in the maximum extension state, the maximum extension state determination unit B transmits a two-stage maximum extension signal indicating that fact. The extension stop valve 40 switches from the opening position a to the shutoff position b by receiving the two-stage maximum extension from the maximum extension state determination unit B. As a result, the extension of the two-stage boom body 12 is stopped. Further, when it is determined that the three-stage boom body 13 is in the maximum extension state, the maximum extension state determination unit B transmits a three-stage maximum extension signal indicating that fact. The maximum extension state determination unit B transmits the three-stage maximum extension signal even when the extension amount of the three-stage boom body 13 becomes the same as the extension amount of the two-stage boom body 13. The extension stop valve 40 switches from the opening position a to the shutoff position b by receiving the three-stage maximum extension signal from the maximum extension state determination unit B. As a result, the extension of the three-stage boom body 13 is stopped.

The switching determination unit Q is a two-stage signal or a three-stage signal in which the two-stage three-stage switching valve 36 is set to the two-stage expansion / contraction position a based on the signals input from the two-stage three-stage changeover switch 51a and the maximum extension state determination unit B. A three-stage signal for the expansion / contraction position b is transmitted to the two-stage three-stage switching valve 36. Specifically, when the switching determination unit Q receives the two-stage maximum extension signal from the maximum extension state determination unit B, the switching determination unit Q is in a state in which only the three-stage signal can be transmitted to the two-stage three-stage switching valve 36. In this state, when a signal indicating the third stage is input from the two-stage three-stage changeover switch 51a to the switching determination unit Q, the switching determination unit Q transmits the three-stage signal to the two-stage three-stage switching valve 36. When the switching determination unit Q receives the two-stage maximum extension signal from the maximum extension state determination unit B, the switching determination unit Q transmits the three-stage signal to 2 even if it does not receive the signal indicating the third stage from the two-stage three-stage changeover switch 51a. It may be sent to the three-stage switching valve 36. In this case, the state in which the two-stage boom body 12 can be extended is automatically switched to the state in which the three-stage boom body 13 can be extended. On the other hand, when the switching determination unit Q has not received the two-stage maximum extension signal from the maximum extension state determination unit B, the switching determination unit Q sends the signal from the two-stage three-stage changeover switch 51a as it is to the two-stage three-stage switching valve 36.

Each stepped amount calculation unit C calculates the insertion amount of the two-stage boom body 12 and the insertion amount of the three-stage boom body 13 based on the detected values of the length totals 51c and 51d, and the calculation result. Is output.

Each boom body length calculation unit E calculates the length of the two-stage boom body 12 and the length of the three-stage boom body 13 based on the detected values of the length totals 51c and 51d, and outputs the calculation result.

Based on the signal (signal indicating the mode) from the mode determination unit A, the rated total load table selection unit D selects the rated total load table according to the signal and outputs the selection result.

The boom angle calculation unit F calculates the angle of the boom 10 based on the signal from the boom angle meter 51e, and outputs the calculation result.

The working radius calculation unit G calculates the working radius of the boom 10 based on the length of each boom body calculated by each boom body length calculation unit E and the angle of the boom 10 calculated by the boom angle calculation unit F. , The calculation result is output.

The pressure calculation unit H calculates the pressure acting on the undulation cylinder 21 based on the signal received from the pressure detector 51f, and outputs the calculation result.

The actual load calculation unit I calculates the actual load from the work radius calculated by the work radius calculation unit G and the pressure of the undulating cylinder 21 calculated by the pressure calculation unit H, and outputs the calculation result.

The rated total load calculation unit J includes a rated total load table selected by the rated total load table selection unit D according to the mode determined by the mode determination unit A, a working radius calculated by the working radius calculation unit G, and the working radius. The total rated load is calculated based on the length of each boom body calculated by the boom body length calculation unit E, and the calculation result is output.

The comparison unit L determines whether or not the load is overloaded by comparing the actual load calculated by the actual load calculation unit I with the total rated load calculated by the rated total load calculation unit J, and determines whether or not the load is overloaded. When it is determined that the load is in the load state, a signal for switching the overload automatic stop valve 43 from the shutoff position a to the open position b is transmitted to the overload automatic stop valve 43. As a result, the operation of the boom 10 is stopped.

The reaction force calculation unit K is the actual load calculated by the actual load calculation unit I, the insertion amount of each boom body calculated by each boom body insertion amount calculation unit C, and each boom body length calculation unit E. The push-up reaction force acting on each reaction force receiving unit is calculated based on the calculated length of each boom body and the boom angle calculated by the boom angle calculation unit F, and the calculation result is output. In the crane mode, the thrust reaction force acting on each reaction force receiving unit or the number of times thereof is very small as compared with that in the basic mode, so that the reaction force calculation unit K receives a signal indicating the basic mode from the mode discriminating unit A. The push-up reaction force is calculated only when this is done.

The stress calculation unit M calculates the stress (approximate value) generated in each reaction force receiving unit based on the thrust reaction force calculated by the reaction force calculation unit K and the stress concentration coefficient map 51g, and calculates the calculation result. Output.

The fatigue degree calculation unit N calculates the degree of accumulation of fatigue in the reaction force receiving unit due to the action of one push-up reaction force based on the stress calculated by the stress calculation unit M and the SN diagram 51h. Along with the calculation, the calculation result is output.

The lifting presence / absence determination unit O determines that the lifting has been performed once when the actual load calculated by the actual load calculation unit I changes from less than a predetermined value to a predetermined value or more. The lifting presence / absence determination unit O corresponds to an action number calculation unit that calculates the action number of the push-up reaction force.

The fatigue accumulation degree calculation unit P calculates the fatigue accumulation degree based on the number of times the lifting presence / absence determination unit O is determined to have been lifted and the fatigue degree calculated by the fatigue degree calculation unit N, and calculates the calculation result. Output.

The creating unit R is the fatigue accumulation degree calculated by the fatigue accumulation degree calculation unit P and the insertion amount of each boom body calculated by each boom body insertion amount calculation unit C (position of the rear end portion of each boom body). The fatigue accumulation information (graph shown in FIG. 5) is created based on the above, and the fatigue accumulation information is output to the monitor 53 in the cabin 3. Further, in addition to the fatigue accumulation information, the monitor 53 also displays the current position of the rear end portion of the two-stage boom body 12 and the position of the rear end portion of the three-stage boom body 13. That is, the creation unit R and the monitor 53 form an information presentation system that presents information about the boom 10.

As shown in FIG. 5, the fatigue accumulation information includes the fatigue accumulation degree for each of a plurality of (four in FIG. 5) sections having a predetermined length in the expansion / contraction direction of the boom 10 in each boom body. It is shown. The values on the horizontal axis of this graph indicate the insertion amount of each boom body or the position of the rear end portion. The vertical axis of the graph shows the degree of fatigue accumulation. The value on the vertical axis is the number of times the stress σ1 acts on the number of times (the number of times the boom body breaks) N1 determined by the stress σ1 acting on the boom body and the SN diagram (the number of times the stress σ1 acts on the boom body (lifting presence / absence determination unit O). The ratio of the number of times counted in) is shown.

The fatigue accumulation information may be represented by the actual length of each section as shown in FIG. 6, or the fatigue accumulation degree is a numerical value as shown in FIGS. 7 and 8. It may be the one displayed by. Further, as shown in FIG. 9, the fatigue accumulation degree may be displayed by a shade of color (for example, a dark-colored section has a high fatigue accumulation degree). Alternatively, the degree of fatigue accumulation may be notified by voice. In this case, the degree of fatigue accumulation for each section and the current position of the rear end of each boom body are notified by voice.

Next, the operation of the crane described above will be described. When this crane is operated in the crane mode, the controller 52 does not calculate the push-up reaction force, that is, does not create fatigue accumulation information. Therefore, only the case of operating in the basic mode will be described here.

When the crane operator selects the basic mode with the mode changeover switch 51b and selects the second stage with the two-stage three-stage changeover switch 51a in the state where the length of the boom 10 is the shortest, the changeover determination unit Q determines. Since the two-stage maximum extension signal is not received from the maximum extension state determination unit B and the signal indicating the second stage is received from the two-stage three-stage changeover switch 51a, the changeover determination unit Q is set to the two-stage three-stage switching valve 36. Sends a two-stage signal. As a result, the two-stage three-stage switching valve 36 becomes the two-stage expansion / contraction position a. In that state, when the operator in the cabin 3 operates the operation unit (not shown) for expanding and contracting the boom 10, the two-stage boom body 12 starts to expand.

After the two-stage boom body 12 has a desired length (the length of the two-stage boom body 12 is shorter than the maximum extension state), when the operator selects three stages with the two-stage three-stage changeover switch 51a, the switching determination is made. Since the unit Q does not receive the two-stage maximum extension signal from the maximum extension state determination unit B and receives a signal indicating the third stage from the two-stage three-stage changeover switch 51a, the switching determination unit Q receives the two-stage three-stage changeover switch Q. A three-stage signal is sent to the switching valve 36. As a result, the 2-stage 3-stage switching valve 36 is switched to the 3-stage expansion / contraction position b. On the other hand, when the two-stage boom body 12 reaches the maximum extension state during the extension operation of the two-stage boom body 12, the maximum extension state determination unit B switches the extension stop valve 40 to the cutoff position b at the extension stop valve 40. Since the signal is sent, the extension of the two-stage boom body 12 is stopped. At this time, the switching determination unit Q is in a state where only the 3-stage signal can be transmitted to the 2-stage 3-stage switching valve 36, and notifies the operator of information prompting the operator to switch to the 3-stage. This information is notified by display on the monitor 53, voice, or the like. Then, when the operator selects three stages with the two-stage three-stage changeover switch 51a, the two-stage three-stage switching valve 36 is switched to the three-stage expansion / contraction position b. When the switching determination unit Q is configured to send the 3-stage signal to the 2-stage 3-stage switching valve 36 when the 2-stage maximum extension signal is received from the maximum extension state determination unit B, the operator is 2 Even if the 3-stage changeover switch 51a does not select the 3-stage, the 2-stage 3-stage changeover valve 36 automatically switches to the 3-stage telescopic position b.

When the two-stage three-stage switching valve 36 is switched to the three-stage expansion / contraction position b and the operator operates the operation unit to the extension side in this state, the three-stage boom body 13 starts to extend. Then, when the extension amount of the three-stage boom body 13, that is, the total length of the boom 10 reaches a desired length, the operation unit is returned to the neutral position. Even if the operator continues to operate the operation unit on the extension side, if the extension amount of the three-stage boom body 13 becomes the same as the extension amount of the two-stage boom body 12, the maximum extension state determination unit Since B transmits the three-stage maximum extension signal to the extension stop valve 40, the extension of the three-stage boom body 13 is stopped at that time.

In that state, civil engineering work and the like are performed. Then, the 1-stage reaction force receiving portion that receives the push-up reaction force from the rear end portion of the 2-stage boom body 12 of the 1-stage boom body 11 and the rear end portion of the 3-stage boom body 13 of the 2-stage boom body 12 Fatigue accumulates in the two-stage reaction force receiving part that receives the push-up reaction force.

In the present embodiment, the fatigue accumulation information created by the creating unit R (reaction force receiving a push-up reaction force from the rear end portion of the boom bodies 12 and 13 one step ahead of the boom bodies 11 and 12 among the boom bodies 11 and 12). Information indicating the relationship between the degree of accumulation of fatigue in the parts and the positions of the rear ends of the boom bodies 12 and 13) and the positions of the rear ends of the boom bodies 12 and 13 are displayed on the monitor 53. To. Therefore, when the operator adjusts the length of the boom 10 in the next and subsequent work, the fatigue accumulation information of the one-stage boom body 11 displayed on the monitor 53 and the rear end portion of the current two-stage boom body 12 While checking the position, adjust the position (insertion amount) of the rear end portion of the two-stage boom body 12 so as to avoid the portion of the one-stage boom body 11 having a high degree of fatigue accumulation, and display it on the monitor 53. While confirming the fatigue accumulation information of the two-stage boom body 12 and the position of the rear end portion of the three-stage boom body 13 at the present time, 3 so as to avoid the portion of the two-stage boom body 12 having a high degree of fatigue accumulation. The position (insertion amount) of the rear end portion of the step boom body 13 can be adjusted. As a result, the fatigue accumulated in the one-stage boom body 11 and the two-stage boom body 12 can be made uniform, so that the one-stage boom body 11 and the two-stage boom body 12 are intensively pushed up only to a specific part. The life of the one-stage boom body 11 and the two-stage boom body 12 is longer than in the case where the reaction force acts repeatedly. Therefore, the durability (life) of the boom 10 can be improved without significantly increasing the size or weight.

Further, the creating unit of the controller 52 creates fatigue accumulation information in each of the boom bodies 11 and 12 indicating the degree of fatigue accumulation in each of a plurality of sections. Therefore, the fatigue accumulated in a plurality of places in each section is added up and displayed as the fatigue of that section. Since this display is in line with the actual fracture mode, the fatigue accumulation information is a more effective guideline.

Further, the stress calculation unit M calculates the stress acting on the reaction force receiving unit based on the stress concentration coefficient map 51 g and the push-up reaction force. Therefore, the stress generated in each reaction force receiving portion from the push-up reaction force can be easily obtained. Therefore, fatigue accumulation information can be easily created as compared with the case of calculating the theoretical stress value, that is, the case of calculating the stress from the push-up reaction force by simulation using a detailed analysis model.

It should be noted that the embodiments disclosed this time are exemplary in all respects and are not considered to be restrictive. The scope of the present invention is shown by the scope of claims rather than the description of the above-described embodiment, and further includes all modifications within the meaning and scope equivalent to the scope of claims.

For example, the three-stage boom body 13 may be omitted. Alternatively, the boom 10 may have four or more boom bodies.

Further, the horizontal axis of the fatigue accumulation information may be continuously displayed without being divided into sections.

1 Swing body (crane body)
10 Boom 11 1st boom body 12 2nd boom body 13 3rd boom body 21 Undulating cylinder 22 2nd stage hydraulic cylinder 23 3rd stage hydraulic cylinder 50 Information processing unit 51 Input unit 51a 2nd stage 3 stage changeover switch (switching unit)
51b Mode selector switch 51c 1st length meter 51d 2nd length meter 51g Stress concentration coefficient map 51h S-N diagram 52 Controller 53 Monitor (display)
M Stress calculation unit O Number of actions calculation unit P Fatigue accumulation degree calculation unit R Creation unit

Claims (7)

The crane body, the one-stage boom body that is undulating and tubular with respect to the crane body, and the first-stage boom body that is movable and tubular in the axial direction of the first boom body. A boom including a two-stage boom body, an undulating cylinder that undulates the one-stage boom body with respect to the crane body, and a two-stage hydraulic cylinder that expands and contracts the two-stage boom body with respect to the one-stage boom body. A system that presents information about the boom of a crane equipped with.
It is the degree of accumulation of fatigue accumulated in the one-stage reaction force receiving portion, which is a portion of the one-stage boom body that receives the push-up reaction force acting on the one-stage boom body from the rear end portion of the two-stage boom body. Based on the 1-step stress generated in the 1-step reaction force receiving portion due to the push-up reaction force, the number of times the push-up reaction force acts on the 1-step reaction force receiving portion, and the previously acquired SN diagram. A creation unit that creates fatigue accumulation information indicating the relationship between the fatigue accumulation degree calculated by the above and the position of the rear end portion of the two-stage boom body.
A crane information presentation system including the fatigue accumulation information and a display unit for displaying the position of the rear end portion of the two-stage boom body. In the crane information presentation system according to claim 1,
As the fatigue accumulation information, the creating unit indicates the degree of fatigue accumulation for each of a plurality of sections of the one-stage boom body having a predetermined length in each moving direction of the two-stage boom body. Crane information presentation system to be created. In the crane information presentation system according to claim 1 or 2.
It also has a stress calculation unit that calculates the one-step stress.
When the stress calculation unit has a theoretical stress value theoretically calculated based on the push-up reaction force acting on the one-stage reaction force receiving part and the push-up reaction force acts on the one-step reaction force receiving part. Based on the stress concentration coefficient map obtained in advance showing the relationship between the measured stress value, which is the measured value of the actual stress generated in the one-step reaction force receiving portion, and the push-up reaction force, the one-step stress. Crane information presentation system to calculate. In the crane information presentation system according to any one of claims 1 to 3.
It further has an action number calculation unit for calculating the action number of the push-up reaction force.
The number of actions calculation unit changed the actual load calculated based on the length of the boom, the angle of the boom with respect to the crane body, and the pressure of the undulating cylinder from less than a predetermined value to more than the predetermined value. A crane information presentation system that calculates the number of actions by accumulating the number of times. In the crane information presentation system according to any one of claims 1 to 4.
The boom further includes a three-stage boom body that is movable within the two-stage boom body in the axial direction of the two-stage boom body.
A three-stage hydraulic cylinder that expands and contracts the three-stage boom body with respect to the two-stage boom body,
From the state where the extension of the two-stage hydraulic cylinder is allowed so that the two-stage boom body extends with respect to the one-stage boom body, the three-stage boom body extends so as to extend with respect to the two-stage boom body. A crane information presentation system further equipped with a switching unit that switches to a state that allows the extension of the step hydraulic cylinder. In the crane information presentation system according to claim 5,
The creating unit is a two-stage reaction force receiving portion which is a portion of the two-stage boom body that receives a push-up reaction force acting on the two-stage boom body from the rear end portion of the three-stage boom body as the fatigue accumulation information. The degree of accumulation of fatigue, which is the number of times the two-stage stress generated in the two-stage reaction force receiving portion due to the pushing-up reaction force and the number of times the pushing-up reaction force acts on the two-stage reaction force receiving portion in advance. Information indicating the relationship between the fatigue accumulation degree calculated based on the acquired SN diagram and the position of the rear end portion of the three-stage boom body is further created.
The display unit is a crane information presentation system that further displays the position of the rear end portion of the three-stage boom body. Crane body and
A boom including a one-stage boom body that is undulating and tubular with respect to the crane body and a two-stage boom body that can be expanded and contracted with respect to the one-stage boom body.
A two-stage hydraulic cylinder that expands and contracts the two-stage boom body with respect to the one-stage boom body,
With an information presentation unit that presents information about the boom,
The information presentation unit is
It is the degree of accumulation of fatigue accumulated in the one-stage reaction force receiving portion, which is a portion of the one-stage boom body that receives the push-up reaction force acting on the one-stage boom body from the rear end portion of the two-stage boom body. Based on the one-step stress generated in the one-step reaction force receiving portion due to the push-up reaction force, the number of times the push-up reaction force acts on the one-step reaction force receiving portion, and the SN diagram acquired in advance. A creation unit that creates fatigue accumulation information indicating the relationship between the fatigue accumulation degree calculated by the above and the position of the rear end portion of the two-stage boom body.
A crane having the fatigue accumulation information and a display unit for displaying the position of the rear end portion of the two-stage boom body.

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