JP6984174B2 - crane - Google Patents

Description

The present invention relates to a crane, and particularly to a technique for detecting a winch erroneous selection in a crane having a plurality of winches.

Conventionally, the crane is provided with a safety device for preventing the crane from tipping over and preventing the wire rope from being overloaded. In particular, the safety device in a crane having a plurality of winches is configured so that the operator can select which winch is used for work by using a button, a switch, a touch panel, or the like (see, for example, Patent Document 1). ..

However, since the safety device as described above is based on the premise that the operator selects the work, that is, the winch is selected correctly, the conventional crane is provided with a function to detect the wrong winch selection by the operator. There was a risk that the winch selected by the operator would be different from the winch used in the actual work.

As a method of detecting the wrong selection of the winch by the operator, the tension of the wire rope calculated from the pressure of the hydraulic oil supplied to the hydraulic motor of the winch and the item set in the safety device (for example, the winding of the wire rope) It is conceivable to detect the wrong selection of the winch by the difference from the tension of the wire rope calculated from the number, the pressure of the undulating cylinder, etc.). However, it is disadvantageous in that the configuration becomes complicated because a plurality of hydraulic sensors are required and the tension of the wire rope needs to be calculated.

Japanese Unexamined Patent Publication No. 2011-105511

An object of the present invention is to provide a crane capable of detecting a winch erroneous selection by an operator with a simple configuration.

The first aspect of the present invention is a hydraulic pump that discharges hydraulic oil, a hydraulic cylinder that raises and lowers a boom with hydraulic oil discharged from the hydraulic pump, and a hydraulic pressure sensor for a cylinder that detects the hydraulic pressure value of the hydraulic cylinder. A plurality of winches that are operated by hydraulic oil discharged from the hydraulic pump to wind and lower the wire rope, a detection means for detecting the operating state of the plurality of winches, and one of the plurality of winches. The type of work to be used is connected to the safety device configured to be inputtable, the hydraulic pressure sensor for the cylinder, the detection means, and the safety device, and is input to the safety device based on the information obtained from them. It is a crane equipped with a control device for determining the selection of a winch corresponding to the type of work, and lifts and conveys a predetermined suspended load. The control device is the hydraulic pressure acquired from the hydraulic pressure sensor for a cylinder. Based on the value of the hydraulic pressure of the cylinder, it is determined whether or not the suspended load work cycle, which is a series of operations for the suspended load, has been performed, and when it is determined that the suspended load work cycle has been performed, the suspended load work cycle has been performed. Whether or not the winch corresponding to the type of work input to the safety device acquired from the safety device by acquiring the operating state of the plurality of winches in the above-mentioned detection means is operated in the suspension work cycle. If it is determined that the operation has not been performed, it is determined that the type of work input to the safety device is incorrect, and the pressure of the hydraulic oil discharged from the hydraulic pump is detected. Further equipped with a hydraulic pressure sensor for a pump connected to a control device, the control device may be subjected to the plurality of operations in the suspension work cycle from the operating state of the plurality of winches in the suspension work cycle acquired from the detection means. It is determined whether or not any of the winches of the above has independently wound the wire rope, and if it is determined that the winding of the wire rope has been performed, the winch that has independently wound the wire rope has acquired the safety device from the safety device. It is determined whether or not it matches the winch corresponding to the type of work input to, and if it does not match, the pressure of the hydraulic oil acquired from the hydraulic pressure sensor for the pump is more than a predetermined threshold when the wire rope is wound up. When the pressure is small, or when the pressure of the hydraulic oil acquired from the hydraulic pressure sensor for the pump is equal to or higher than the predetermined threshold value for less than the predetermined time, it is determined that the type of work input to the safety device is correct. Then, when the pressure of the hydraulic oil acquired from the hydraulic pressure sensor for the pump continues to be in a state of the predetermined threshold value or more for the predetermined time or more, it is determined that the type of work input to the safety device is incorrect. ..

According to the first aspect of the present invention, it is determined whether or not a suspended load work cycle, which is a series of operations for suspended loads, has been performed based on the hydraulic pressure change of the hydraulic cylinder, and the suspended load work cycle is actually used. Compare the activated winch with the winch corresponding to the type of work entered into the safety device. This makes it possible to detect a winch erroneous selection by the operator with a simple configuration.

According to the second aspect of the present invention, when the winch in which the wire rope is wound independently in the suspended load work cycle and the winch corresponding to the type of work input to the safety device do not match, a predetermined condition is obtained. Only below is the type of work entered into the safety device determined to be incorrect. As a result, it is possible to detect the wrong selection of the winch by the operator with low cost and accuracy.

The side view which shows the whole structure of the crane which concerns on one Embodiment of this invention. The side view which shows the tip part of the boom of the crane which concerns on one Embodiment of this invention. The figure which shows the cockpit of the crane which concerns on one Embodiment of this invention. (A) The figure which shows the display screen in the safety device of the crane which concerns on one Embodiment of this invention, (b) is the figure which shows the display screen which also sets the type of work. The figure which shows the hydraulic circuit for the main winch of the crane which concerns on one Embodiment of this invention. The figure which shows the hydraulic circuit for the sub winch of the crane which concerns on one Embodiment of this invention. The figure which shows the hydraulic circuit for the undulating cylinder of the crane which concerns on one Embodiment of this invention. The figure which shows the structure of the control device of the crane which concerns on one Embodiment of this invention. The figure which shows the method of calculating the suspension load from the undulating thrust and the state of a boom in the crane which concerns on one Embodiment of this invention. The figure which shows the suspension work cycle. The figure which shows the first judgment by a control device. The figure which shows another form of the hydraulic circuit for a main winch. The figure which shows the 2nd determination by a control device.

Hereinafter, the crane 1, which is an embodiment of the crane according to the present invention, will be described with reference to FIGS. 1 to 4. The crane 1 according to this embodiment is a mobile crane that can be moved to an arbitrary place. However, the present invention is not limited thereto, and may be any crane provided with a boom undulated by a hydraulic cylinder and a plurality of hydraulic winches.

As shown in FIG. 1, the crane 1 includes a vehicle 2 and a crane device 6.

The vehicle 2 conveys the crane device 6. The vehicle 2 has a plurality of wheels 3 and runs on the engine 4 (see FIG. 5) as a power source. The vehicle 2 is provided with an outrigger 5. The outrigger 5 has an overhang beam that can be extended hydraulically on both sides of the vehicle 2 in the width direction, and a hydraulic jack cylinder that can be extended in a direction perpendicular to the ground. The vehicle 2 can expand the workable range of the crane 1 by extending the overhanging beam of the outrigger 5 to both sides in the width direction of the vehicle 2 and grounding the jack cylinder.

The crane device 6 lifts the suspended load W with a wire rope. The crane device 6 includes a swivel 7, a telescopic boom 8, a jib 13, a main hook block 14, a sub hook block 15, an undulating cylinder 16, a main winch 17, a sub winch 18, a main wire rope 19, a sub wire rope 20, and a cabin 21. , And a safety device 23 (see FIG. 3).

The swivel base 7 is configured to be able to swivel the crane device 6. The swivel base 7 is provided on the frame of the vehicle 2 via an annular bearing. The annular bearing is arranged so that its center of rotation is perpendicular to the installation surface of the vehicle 2. The swivel base 7 is rotatably configured with the center of the annular bearing as the center of rotation. Further, the swivel base 7 is configured to be rotated by a hydraulic swivel motor (not shown).

The telescopic boom 8 is a boom that supports the wire rope so that the suspended load W can be lifted. The telescopic boom 8 is composed of a plurality of boom members, a base boom member 8a, a second boom member 8b, a third boom member 8c, a force boom member 8d, a fifth boom member 8e, and a top boom member 8f. The plurality of boom members are formed in a cylindrical shape having polygonal cross sections similar to each other. The plurality of boom members are formed so that other boom members can be inserted into one boom member in descending order of cross-sectional area. That is, the top boom member 8f having the smallest cross-sectional area is formed so as to be insertable inside the fifth boom member 8e having the second largest cross-sectional area after the top boom member 8f. The Fifth boom member 8e is formed so as to be insertable inside the force boom member 8d having the second largest cross-sectional area after the Fifth boom member 8e. As described above, in the telescopic boom 8, the second boom member 8b, the third boom member 8c, the force boom member 8d, the fifth boom member 8e, and the top boom member 8f have a cross-sectional area inside the base boom member 8a having the largest cross-sectional area. It is inserted in a nested manner in descending order of.

Further, in the telescopic boom 8, the second boom member 8b, the third boom member 8c, the force boom member 8d, the fifth boom member 8e, and the top boom member 8f can move in the axial direction of the telescopic boom 8 with respect to the base boom member 8a. It is configured in. That is, the telescopic boom 8 is configured to be telescopic by moving each boom member by a telescopic cylinder (not shown). The telescopic boom 8 is provided so that the base end of the base boom member 8a can swing on the swivel base 7. In this way, the telescopic boom 8 is configured to be horizontally rotatable on the frame of the vehicle 2. Further, the telescopic boom 8 is configured to swing freely around the base end of the base boom member 8a with respect to the swivel base 7.

As shown in FIG. 2, a main guide sheave 9, a sub guide sheave 10, a plurality of main sheaves 11, and a sub sheave 12 are provided at the tip of the top boom member 8f of the telescopic boom 8. On the back side of the tip of the top boom member 8f (the side surface on the swinging direction side when the telescopic boom 8 stands up), the main guide sheave 9 around which the main wire rope 19 is wound and the sub guide sheave around which the sub wire rope 20 is wound. 10 is rotatably provided. On the ventral side of the tip of the top boom member 8f (the side surface opposite to the swing direction when the telescopic boom 8 stands up), a sub-sheave 12 around which the sub wire rope 20 is wound and a main wire rope 19 are arranged in order from the tip side. A plurality of main sheaves 11 to be wound are rotatably provided. Further, a jib support portion 8g is provided at the tip end portion of the top boom member 8f. The telescopic boom 8 includes a boom length detection sensor 56 (see FIG. 8) that detects the boom length L (see FIG. 9) and an undulation angle detection sensor 57 (see FIG. 9) that detects the undulation angle θ (see FIG. 9). 8) and are provided.

As shown in FIG. 1, the jib 13 expands the lift and working radius of the crane device 6. The jib 13 is held in a posture along the top boom member 8f by a jib support portion 8g provided on the top boom member 8f of the telescopic boom 8. The base end of the jib 13 is configured to be connectable to the jib support portion 8g of the top boom member 8f. The jib 13 is configured to be connectable to the tip of the top boom member 8f of the telescopic boom 8 by driving a pin (not shown) into the jib support portion 8g.

The main hook block 14 is a member for suspending the suspended load W. The main hook block 14 is provided with a main hook 14a for hooking on the suspended load W and a plurality of hook sheaves 14b around which the main wire rope 19 is wound.
The sub-hook block 15 is a member for suspending the suspended load W. The sub-hook block 15 is provided with a sub-hook 15a for hooking on the suspended load W.

The undulating cylinder 16 causes the telescopic boom 8 to stand up and down, and maintains the posture of the telescopic boom 8. The undulating cylinder 16 is a hydraulic cylinder including a cylinder portion and a rod portion. The undulating cylinder 16 is configured so that the moving direction of the rod portion is switched by selectively supplying hydraulic oil to the oil chamber 16a on the head side (see FIG. 7) and the oil chamber 16b on the rod portion side (see FIG. 7). There is. In the undulating cylinder 16, the end portion of the cylinder portion is swingably connected to the swivel base 7, and the end portion of the rod portion is swingably connected to the base boom member 8a of the telescopic boom 8. As a result, the undulating cylinder 16 raises the base boom member 8a by supplying hydraulic oil so that the rod portion is pushed out from the cylinder portion, and the hydraulic oil is supplied so that the rod portion is pushed back to the cylinder portion. As a result, the base boom member 8a is configured to lie down.

The main winch 17 is a hydraulic winch that feeds (winds up) and unwinds (rolls down) the main wire rope 19. The main winch 17 is configured such that the main drum 17b (see FIG. 5) around which the main wire rope 19 is wound is rotated by the main hydraulic motor 17a (see FIG. 5). The main winch 17 pays out the main wire rope 19 wound around the main drum 17b by supplying hydraulic oil so that the main hydraulic motor 17a rotates in one direction, and the main hydraulic motor 17a moves in the other direction. The main wire rope 19 is wound around the main drum 17b by being supplied with hydraulic oil so as to rotate, and is configured to be fed.

The sub winch 18 is a hydraulic winch that feeds (winds up) and unwinds (rolls down) the sub wire rope 20. The sub winch 18 is configured such that the sub drum 18b (see FIG. 6) around which the sub wire rope 20 is wound is rotated by the sub hydraulic motor 18a (see FIG. 6). The sub winch 18 is supplied with hydraulic oil so that the sub hydraulic motor 18a rotates in one direction, so that the sub wire rope 20 wound around the sub drum 18b is unwound, and the sub hydraulic motor 18a rotates in the other direction. The sub-wire rope 20 is wound around the sub-drum 18b by being supplied with hydraulic oil so as to be wound around the sub-drum 18b.

The main wire rope 19 is wound around the plurality of main sheaves 11 and the plurality of hook sheaves 14b from the main winch 17 via the main guide sheave 9 (see FIG. 2). The end of the main wire rope 19 is fixed to the top boom member 8f.
The sub wire rope 20 is connected to the sub hook block 15 from the sub winch 18 via the sub guide sheave 10 and the sub sheave 12.

The cabin 21 covers the cockpit 22 (see FIG. 3). The cabin 21 is provided on the side of the telescopic boom 8 on the swivel table 7. A driver's seat 22 is provided inside the cabin 21.
As shown in FIG. 3, the cockpit 22 has a main operating tool 22a for operating the main winch 17, a sub operating tool 22b for operating the sub winch 18, and undulations for operating the telescopic boom 8. An operation tool 22c, a handle 22d for moving the crane 1, an alarm buzzer 22e as a notification means, and a safety device 23 are provided.

As shown in FIG. 4A, the safety device 23 includes a display monitor such as a touch panel, and is configured so that the operator can make various settings from the display screen of the display monitor. On the display screen of the display monitor, the boom length L of the telescopic boom 8 and the undulation angle θ of the telescopic boom 8 are displayed. Further, the display screen of the display monitor displays load information, a turning position, the number of windings of the main wire rope 19, and the like.

As shown in FIG. 4B, the safety device 23 is configured so that the work type WT can be set as one of various settings by the operator. Types of work WT includes a main hook work in which the main winch 17 is operated and the main hook 14a is used in the telescopic boom 8, a sub hook work in which the sub winch 18 is operated and the sub hook 15a is used in the telescopic boom 8, and a sub. It includes jib work in which the sub-hook 15a is used in the jib 13 mounted on the telescopic boom 8 by operating the winch 18.
The safety device 23 is configured so that the operator can select one of the main hook work, the sub hook work, and the jib work via the display screen of the display monitor. That is, the safety device 23 is configured so that the winch to be operated can be selected by the operator from the main winch 17 and the sub winch 18.

The crane 1 configured in this way can move the crane device 6 to an arbitrary position by traveling the vehicle 2. Further, the crane 1 raises the telescopic boom 8 with an undulating cylinder 16 at an arbitrary undulating angle, extends the telescopic boom 8 to an arbitrary boom length, and connects the jib 13 to the lift of the crane device 6. And the working radius can be expanded. Further, the crane 1 can select whether to use the main winch 17 or the sub winch 18 according to the weight of the suspended load W and the desired lifting speed.

Hereinafter, the hydraulic circuits related to the undulating cylinder 16, the main winch 17, and the sub winch 18 included in the crane 1 will be described with reference to FIGS. 5 to 7.

As shown in FIGS. 5 to 7, the hydraulic circuits include a hydraulic pump 25 in which the driving force from the engine 4 is conducted, a main hydraulic circuit 28 (see FIG. 5), and a sub hydraulic circuit 37 (see FIG. 6). , A hydraulic circuit for undulation 46 (see FIG. 7), and a control device 54.

The hydraulic pump 25 discharges hydraulic oil. The hydraulic pump 25 is driven by the engine 4. The hydraulic oil discharged from the hydraulic pump 25 is supplied to the main hydraulic circuit 28, the sub hydraulic circuit 37, and the undulating hydraulic circuit 46. A relief valve 27 is provided in the discharge oil passage 26 of the hydraulic pump 25.

As shown in FIG. 5, the main hydraulic circuit 28 operates the main winch 17. The main hydraulic circuit 28 includes a main hydraulic motor 17a, a main operating tool 22a, a main pilot type switching valve 29, a main counter balance valve 32, and a main operating position detector 36.

The main hydraulic motor 17a rotates the main drum 17b of the main winch 17. The main hydraulic motor 17a is configured to be interlocked with the main drum 17b. The main hydraulic motor 17a rotates the main drum 17b in the direction in which the main wire rope 19 is fed when the hydraulic oil is supplied to the plunger on the feeding side. The main hydraulic motor 17a rotates the main drum 17b in the direction in which the main wire rope 19 is fed when the hydraulic oil is supplied to the plunger on the feeding side.

The main operating tool 22a is formed in a lever shape that can be operated by an operator, and controls the operation of the main winch 17. The main operating tool 22a includes a switching valve capable of switching the pilot pressure applied to the main pilot type switching valve 29 by an external operation. The hydraulic oil is supplied to the main operating tool 22a so that the pilot pressure is applied from the pressure source. In the present embodiment, the main operating tool 22a is configured as a lever, but is not limited to this as long as it can be operated by the operator, and can be configured as a button, for example.

The main pilot type switching valve 29 switches the direction of the hydraulic oil supplied to the main hydraulic motor 17a. A hydraulic pump 25 is connected to the supply port of the main pilot type switching valve 29 via a discharge oil passage 26. A plunger on the feed-in side of the main hydraulic motor 17a is connected to one port of the main pilot type switching valve 29 via a main one-side oil passage 30. A plunger on the payout side of the main hydraulic motor 17a is connected to the other port of the main pilot type switching valve 29 via the main oil passage 31 on the other side.

In the main pilot type switching valve 29, when the pilot pressure is not applied, the main one-side oil passage 30 and the main other-side oil passage 31 are closed. As a result, the rotation position of the main hydraulic motor 17a is maintained. In the main pilot type switching valve 29, when the pilot pressure is applied so that one port is opened, the hydraulic oil from the hydraulic pump 25 passes through the main one-side oil passage 30 and the main hydraulic motor 17a. It is supplied to the plunger on the transfer side. As a result, the main hydraulic motor 17a is rotated in the direction in which the main wire rope 19 is fed. In the main pilot type switching valve 29, when the pilot pressure is applied so that the other port is opened, the hydraulic oil from the hydraulic pump 25 passes through the main other side oil passage 31 and the main hydraulic motor 17a. It is supplied to the plunger on the delivery side. As a result, the main hydraulic motor 17a is rotated in the direction of feeding out the main wire rope 19.

The main counter balance valve 32 prevents the main hydraulic motor 17a from being rotated by the load applied to the main wire rope 19. The main counter balance valve 32 is provided in the main one-side oil passage 30. The main counter balance valve 32 allows the flow of hydraulic oil discharged from the plunger on the feeding side of the main hydraulic motor 17a only when the hydraulic oil is supplied to the plunger on the feeding side of the main hydraulic motor 17a. ..

The main operation position detector 36 detects the operation position of the main operation tool 22a. The main operation position detector 36 has a neutral position, which is an operation position where the main winch 17 does not operate, a hoisting position, which is an operation position where the main winch 17 operates so that the main wire rope 19 is wound up, and a main wire rope. It is configured to detect the unwinding position, which is the operating position where the main winch 17 operates so that the 19 is unwound. That is, the main operation position detector 36 functions as a detection means for detecting the operating state of the main winch 17.

In the crane 1 provided with the main hydraulic circuit 28 configured as described above, the main pilot type switching valve 29 is operated by the main operating tool 22a to flow the hydraulic oil supplied to the main hydraulic motor 17a. To switch. As a result, the crane 1 can freely advance and extend the main wire rope 19 by the main winch 17 by operating the main operating tool 22a.

As shown in FIG. 6, the sub hydraulic circuit 37 operates the sub winch 18. The sub hydraulic circuit 37 includes a sub hydraulic motor 18a, a sub operation tool 22b, a sub pilot type switching valve 38, a sub counter balance valve 41, and a sub operation position detector 45.
The sub operation position detector 45 detects the operation position of the sub operation tool 22b. The sub operation position detector 45 has a neutral position, which is an operation position where the sub winch 18 does not operate, a hoisting position, which is an operation position where the sub winch 18 operates so that the sub wire rope 20 is wound up, and a sub wire rope. It is configured to detect the unwinding position, which is the operating position at which the sub winch 18 operates so that the 20 is unwound. That is, the sub operation position detector 45 functions as a detection means for detecting the operating state of the sub winch 18.
Since the configuration and operation mode of the sub hydraulic circuit 37 are substantially the same as those of the main hydraulic circuit 28, detailed description thereof will be omitted.

In the crane 1 provided with the sub hydraulic circuit 37 configured in this way, the sub pilot type switching valve 38 is operated by the sub operating tool 22b to flow the hydraulic oil supplied to the sub hydraulic motor 18a. Switch. As a result, the crane 1 can freely carry out the feeding and feeding of the sub wire rope 20 by the sub winch 18 by operating the sub operating tool 22b.

As shown in FIG. 7, the undulating hydraulic circuit 46 operates the undulating cylinder 16. The undulating hydraulic circuit 46 includes an undulating cylinder 16, an undulating operation tool 22c, an undulating pilot type switching valve 47, an undulating counter balance valve 50, an undulating one-side hydraulic sensor 51, an undulating other-side hydraulic sensor 52, and an undulating hydraulic circuit 46. The operation position detector 53 is provided.

The undulating operating tool 22c is operated by an operator to control the operation of the undulating cylinder 16. The undulating operating tool 22c includes a switching valve that can switch the pilot pressure applied to the undulating pilot type switching valve 47 by an external operation. Hydraulic oil is supplied to the undulating operating tool 22c so that pilot pressure is applied from the pressure source.

The undulating pilot type switching valve 47 switches the direction of the hydraulic oil supplied to the undulating cylinder 16. A hydraulic pump 25 is connected to the supply port of the undulating pilot type switching valve 47 via a discharge oil passage 26. An oil chamber 16a on the head side of the undulating cylinder 16 is connected to one port of the undulating pilot type switching valve 47 via an undulating one-side oil passage 48. The rod portion side oil chamber 16b of the undulating cylinder 16 is connected to the other port of the undulating pilot type switching valve 47 via the undulating other side oil passage 49.

When the pilot pressure is not applied to the undulating pilot type switching valve 47, the undulating one-side oil passage 48 and the undulating other-side oil passage 49 are closed. As a result, the position of the rod portion of the undulating cylinder 16 is maintained. In the undulating pilot type switching valve 47, when the pilot pressure is applied so that one port is opened, the hydraulic oil from the hydraulic pump 25 passes through the undulating one-side oil passage 48 to the head of the undulating cylinder 16. It is supplied to the side oil chamber 16a. As a result, the rod portion of the undulating cylinder 16 is pushed out from the cylinder portion so as to erect the expansion / contraction boom 8. In the undulating pilot type switching valve 47, when the pilot pressure is applied so that the other port is opened, the hydraulic oil from the hydraulic pump 25 passes through the undulating other side oil passage 49 and the rod of the undulating cylinder 16. It is supplied to the oil chamber 16b on the part side. As a result, the rod portion of the undulating cylinder 16 is pushed back to the cylinder portion so as to lay down the telescopic boom 8.

The undulating counter balance valve 50 prevents the rod portion of the undulating cylinder 16 from being pushed back by the load applied to the expansion / contraction boom 8. The undulating counter balance valve 50 is provided in the undulating one-side oil passage 48. The undulating counter balance valve 50 allows the flow of hydraulic oil discharged from the head side oil chamber 16a of the undulating cylinder 16 only when the hydraulic oil is supplied to the rod portion side oil chamber 16b of the undulating cylinder 16.

The undulating one-sided hydraulic pressure sensor 51 and the undulating other-side hydraulic pressure sensor 52 detect the value of hydraulic pressure. The undulating one-side hydraulic sensor 51 is configured to detect the pressure in the head-side oil chamber 16a of the undulating cylinder 16. The undulating other side hydraulic sensor 52 is configured to detect the pressure in the rod portion side oil chamber 16b of the undulating cylinder 16.

The undulation operation position detector 53 detects the operation position of the undulation operation tool 22c. The undulating operation position detector 53 has a neutral position, which is an operation position where the telescopic boom 8 does not operate, an upright position, which is an operation position where the telescopic boom 8 is erected, and an undulation position, which is an operation position where the telescopic boom 8 is laid down. Is configured to detect.

In the crane 1 provided with the undulating hydraulic circuit 46 configured as described above, the undulating pilot type switching valve 47 is operated by the undulating operating tool 22c to switch the flow of hydraulic oil supplied to the undulating cylinder 16. .. As a result, the crane 1 can freely raise and lower the telescopic boom 8 by the undulating cylinder 16 by operating the undulating operating tool 22c.

Hereinafter, the control device 54 will be described with reference to FIGS. 8 to 11.

As shown in FIG. 8, the control device 54 includes a safety device 23, a main operation position detector 36, a sub operation position detector 45, an undulation one-side hydraulic sensor 51, an undulation other-side hydraulic sensor 52, and an undulation. It is electrically connected to the operation position detector 53. The control device 54 is configured to acquire various information from the above-mentioned connected devices, process them, and output them to the safety device 23.

The control device 54 can acquire the work type WT input by the operator from the safety device 23.

The control device 54 can acquire the operation position of the main operation tool 22a from the main operation position detector 36, that is, either the neutral position, the hoisting position, or the unwinding position.

The control device 54 can acquire the operation position of the sub operation tool 22b from the sub operation position detector 45, that is, either the neutral position, the hoisting position, or the unwinding position.

The control device 54 is connected to the undulating operation position detector 53, and acquires the operating position of the undulating operation tool 22c from the undulating operation position detector 53, that is, either a neutral position, an upright position, or an undulating position. be able to.

The control device 54 acquires the hydraulic pressure value of the head side oil chamber 16a of the undulating cylinder 16 from the undulating one-side hydraulic sensor 51, and the hydraulic pressure of the rod portion side oil chamber 16b of the undulating cylinder 16 from the undulating other-side hydraulic sensor 52. You can get the value of.

The control device 54 is connected to the boom length detection sensor 56 and the undulation angle detection sensor 57, acquires the boom length L (see FIG. 9) from the boom length detection sensor 56, and undulation angle from the undulation angle detection sensor 57. θ (see FIG. 9) can be obtained.

Based on the suspended load load P, the control device 54 determines whether or not a series of operations on the suspended load W in the crane 1, that is, a cycle of ground cutting step → air suspension step → release step has been performed. The suspended load P is the weight of the suspended load W calculated from the undulating thrust TH and information on the expansion / contraction boom 8 (boom length L, undulating angle θ, etc.).
In the present invention, the cycle of the ground cutting process → the air suspension process → the release process, which is a series of operations for the suspended load W, is referred to as a “suspended load work cycle”.

Here, a method of calculating the suspended load P will be described with reference to FIG. In the present embodiment, the calculation of the suspended load P shall describe the case where the suspended load W is suspended only by the telescopic boom 8.

In calculating the suspended load P, the control device 54 first obtains the oil pressure value of the head side oil chamber 16a of the undulating cylinder 16 acquired from the undulating one-side hydraulic sensor 51 and the undulating other-side hydraulic pressure sensor 52. The undulating thrust TH (see the white-painted arrow in FIG. 9) is calculated based on the value of the hydraulic pressure in the oil chamber 16b on the rod portion side of the undulating cylinder 16.
Subsequently, the control device 54 determines the calculated undulating thrust TH, the position C of the center of gravity of the telescopic boom 8 representing the shape and posture of the telescopic boom 8, the weight M of the telescopic boom 8, the boom length L of the telescopic boom 8, and the telescopic boom. The suspended load P (see the black arrow in FIG. 9) is calculated based on the undulation angle θ of 8.

The control device 54 determines whether or not the suspended load work cycle (ground cutting step → air suspension process → release step) has been performed based on the suspended load load P calculated as described above.
In the present embodiment, the suspended load P is the hydraulic pressure value of the head side oil chamber 16a of the undulating cylinder 16 acquired from the undulating one-side hydraulic sensor 51 and the undulating cylinder acquired from the undulating other-side hydraulic sensor 52. It was calculated from the center of gravity position C, the weight M, the boom length L, and the undulation angle θ of the telescopic boom 8 based on the value of the hydraulic pressure of the oil pressure chamber 16b on the rod portion side of 16, but is not limited to this, and at least the hydraulic pressure. It may be calculated based on the value of the hydraulic pressure of the undulating cylinder acquired from the sensor.

As shown in FIG. 10, in the suspended load work cycle, first, the suspended load P gradually increases from the initial value as the wire rope is wound up (ground cutting step), and then the suspended load W is completely lifted. After the suspended load P becomes constant, the suspended load W comes into contact with the ground as the wire rope is unwound, and the suspended load P gradually decreases (suspended in the air), and finally the suspended load. When W is completely placed on the ground, the suspended load P returns to the initial value (release process).

The control device 54 determines that the ground cutting step of the suspended load W has been performed when the state in which the suspended load load P is equal to or higher than the predetermined value continues for a predetermined time or longer. The method for determining the ground cutting process is not limited, and the determination can be made based on the amount of increase in the suspended load P per unit time.
Next, in the control device 54, when the suspended load P remains substantially constant for a predetermined time or longer and then the suspended load P is equal to or less than a predetermined value for a predetermined time or longer, the suspended load W is suspended in the air. Judge that it was done. The method for determining the suspended load P is not limited, and the determination is made based on the amount of decrease in the suspended load P per unit time after the suspended load P has been in a substantially constant state for a predetermined time or longer. Is also possible.
Finally, the control device 54 determines that the release step of the suspended load W has been performed when the suspended load P returns to the initial value and the state continues for a predetermined time or longer.
As described above, the control device 54 determines whether or not the suspended load work cycle has been performed based on the suspended load load P.

In the control device 54, the type of winch actually operated in the suspension work cycle as described above is the type of work preselected by the operator via the safety device 23 WT (main hook work, sub-hook work, and jib work). ) Corresponds to the type of winch. The type of winch operated in the suspended load work cycle is the main operation tool 22a and the sub operation tool 22b in the suspension work cycle acquired from the main operation position detector 36 and the sub operation position detector 45. It is possible to judge based on the operation position of.

As shown in FIG. 11, in the control device 54, when the main hook work for operating the main winch 17 is selected as the work type WT by the operator, the winch operated during the suspension work cycle is only the main winch 17. When, it is determined that there is no abnormality, assuming that the type of winch selected in advance and the type of winch actually operated in the suspended load work cycle match. On the other hand, when the winch used during the suspension work cycle is only the sub winch 18, the control device 54 has an incorrect work type WT preselected by the operator, that is, of the preselected winch. An error is determined as the type and the type of winch actually operated in the suspended load work cycle are different. Further, when the winches operated during the suspension work cycle are both the main winch 17 and the sub winch 18, the control device 54 cannot determine which winch performed the suspension work cycle, and thus determines that there is no abnormality. do.

When the operator selects the sub-hook work or the jib work that operates the sub-winch 18 as the work type WT, and the winch used during the suspension work cycle is only the main winch 17, the control device 54 operates the operator. The preselected work type WT is erroneous, that is, the preselected winch type differs from the actually activated winch type in the suspended work cycle. On the other hand, when the winch used in the suspension work cycle is only the sub winch 18, the control device 54 matches the type of the winch selected in advance with the type of the winch actually operated in the suspension work cycle. As a result, it is determined that there is no abnormality. Further, when the winches operated during the suspension work cycle are both the main winch 17 and the sub winch 18, the control device 54 cannot determine which winch performed the suspension work cycle, and thus determines that there is no abnormality. do.

As described above, the control device 54 includes the operation positions of the main operation tool 22a and the sub operation tool 22b in the suspended load work cycle acquired from the main operation position detector 36 and the sub operation position detector 45. Whether or not the type of winch actually operated in the suspended load work cycle matches the type of winch corresponding to the type of work WT previously selected by the operator, based on the work type WT obtained from the safety device 23. Is determined. This can be achieved without providing various equipment to the conventional crane. Therefore, in the crane 1, it is possible to detect a winch erroneous selection by the operator with a simple configuration.

Further, the control device 54 stores or outputs information on the detected error. Thereby, the life of the main wire rope 19 and the sub wire rope 20 can be calculated accurately by using the detected error information.

The hydraulic circuit (see FIGS. 5 to 7) relating to the undulating cylinder 16, the main winch 17, and the sub winch 18 included in the crane 1 can also be configured as follows.
Hereinafter, the hydraulic circuit according to another embodiment will be described with reference to FIGS. 12 and 13.

As shown in FIG. 12, the hydraulic circuit according to another embodiment includes a hydraulic sensor 24.
The hydraulic pressure sensor 24 is provided in the discharge oil passage 26 of the hydraulic pump 25, and is configured to detect the hydraulic pressure Pa which is the pressure of the hydraulic oil discharged from the hydraulic pump 25.
The hydraulic circuit according to another embodiment is the same as the hydraulic circuit according to the above-described embodiment except that the hydraulic sensor 24 is provided in the discharge oil passage 26 of the hydraulic pump 25.

The control device 54 is connected to the hydraulic sensor 24 and can acquire the pressure of the hydraulic oil discharged from the hydraulic pump 25.

In addition to the determination based on the operation positions of the main operation tool 22a and the sub operation tool 22b during the suspension work cycle (hereinafter referred to as "first determination"), the control device 54 has the same as the above-mentioned embodiment. A determination based on the hydraulic pressure Pa acquired from the hydraulic pressure sensor 24 (hereinafter referred to as "second determination") is performed.

As shown in FIG. 13, in the control device 54, when the main hook work for operating the main winch 17 is selected as the work type WT by the operator, only the hoisting of the sub winch 18 is performed during the suspension work cycle. It is determined whether the operation has been performed, only the winding of the main winch 17 has been performed, or other operations (combination operation of the main winch 17 and the sub winch 18 and their winding down, etc.) have been performed. These determinations are made based on the operating positions of the main operating tool 22a and the sub operating tool 22b in the suspended load work cycle, which are acquired from the main operating position detector 36 and the sub operating position detector 45.

When the control device 54 determines that the main hook work is selected as the work type WT and only the winding of the sub winch 18 is performed during the suspended load work cycle, the hydraulic pressure Pa is smaller than the predetermined threshold value Ps. When (Pa <Ps), it is determined that there is no abnormality because the hydraulic pressure Pa is relatively small and there is no problem (for example, it does not significantly affect the life of the wire rope) although the winch is erroneously selected. Further, when the control device 54 determines that the main hook work is selected as the work type WT and only the winding of the sub winch 18 is performed during the suspended load work cycle, the hydraulic pressure Pa is equal to or higher than a predetermined threshold value Ps. When the state (Pa ≧ Ps) is less than a predetermined time (for example, 3 seconds), it is determined that there is no abnormality, assuming that the abnormal operation is completed immediately.
On the other hand, when the control device 54 determines that the main hook work is selected as the work type WT and only the winding of the sub winch 18 is performed during the suspended load work cycle, the hydraulic pressure Pa is equal to or higher than a predetermined threshold value Ps. When the state (Pa ≧ Ps) continues for a predetermined time (for example, 3 seconds) or more, it is determined that there is an erroneous selection of the winch and an error is determined.

When the control device 54 determines that the main hook work is selected as the work type WT and only the winding of the main winch 17 is performed during the suspended load work cycle, it is determined that there is no erroneous selection of the winch and there is no abnormality. do.

When the control device 54 determines that the main hook work is selected as the work type WT and an operation other than the winding of the main winch 17 and the winding of the sub winch 18 is performed during the suspended load work cycle, the hydraulic pressure is applied. Since the determination based on Pa cannot be made, it is determined that there is no abnormality.

When the operator has selected the sub-hook work or the jib work to operate the sub-winch 18 as the work type WT, the control device 54 has only hoisted the sub-winch 18 during the suspension work cycle, or the main. It is determined whether only the winch 17 has been wound up or other operations (main winch 17 and sub winch 18 combined operation, winding down of them, etc.) have been performed.

When the control device 54 determines that the sub-hook work or the jib work is selected as the work type WT and only the winding of the sub-winch 18 is performed during the suspension work cycle, there is no erroneous selection of the winch and there is no abnormality. Is determined.

When the control device 54 determines that the sub-hook work or the jib work is selected as the work type WT and only the winding of the main winch 17 is performed during the suspension work cycle, the hydraulic pressure Pa is from the predetermined threshold value Pm. When it is also small (Pa <Pm), it is judged that there is no abnormality because the hydraulic pressure Pa is relatively small and there is no problem, although the winch is erroneously selected. Further, when the control device 54 determines that the sub-hook work or the jib work is selected as the work type WT and only the winding of the main winch 17 is performed during the suspension work cycle, the hydraulic pressure Pa is a predetermined threshold value. When the state of Pm or more (Pa ≧ Pm) is less than a predetermined time (for example, 3 seconds), it is determined that there is no abnormality, assuming that the abnormal operation is completed immediately.
On the other hand, when the control device 54 determines that the sub-hook work or the jib work is selected as the work type WT and only the winding of the main winch 17 is performed during the suspension work cycle, the hydraulic pressure Pa is a predetermined threshold value. When the state of Pm or more (Pa ≧ Pm) continues for a predetermined time (for example, 3 seconds) or more, it is determined that there is an erroneous selection of the winch and an error is determined.

When the control device 54 determines that the sub-hook work or the jib work is selected as the work type WT and the operation other than the winding of the main winch 17 and the winding of the sub winch 18 is performed during the suspension work cycle, the control device 54 determines. Since the determination cannot be made based on the hydraulic pressure Pa, it is determined that there is no abnormality.

As described above, the control device 54 is based on the hydraulic pressure Pa acquired from the hydraulic pressure sensor 24, in addition to the first determination based on the operating positions of the main operating tool 22a and the sub operating tool 22b during the suspension work cycle. Make a second decision. As a result, the wrong selection of the winch by the operator can be detected more accurately than in the case of only the first determination. Further, since the second determination can be realized only by providing the hydraulic sensor 24, it is possible to detect the wrong selection of the winch by the operator at low cost.

1 Crane 8 Telescopic boom 13 Jib 14a Main hook 15a Sub hook 16 Undulating cylinder 17 Main winch 18 Sub winch 19 Main wire rope 20 Sub wire rope 22a Main operating tool 22b Sub operating tool 22c Undulating operating tool 23 Safety device 36 Main Operation position detector 45 Sub operation position detector 54 Control device

Claims (1)

A hydraulic pump that discharges hydraulic oil and
A hydraulic cylinder that raises and lowers the boom with hydraulic oil discharged from the hydraulic pump,
A cylinder hydraulic sensor that detects the hydraulic pressure value of the hydraulic cylinder, and
A plurality of winches that are operated by the hydraulic oil discharged from the hydraulic pump to wind and unwind the wire rope.
A detection means for detecting the operating state of the plurality of winches, and
A safety device configured to allow input of the type of work using any of the multiple winches,
A control device connected to the cylinder hydraulic sensor, the detection means, and the safety device, and making a determination regarding selection of a winch corresponding to the type of work input to the safety device based on the information acquired from them. It is a crane that lifts and transports a predetermined suspended load.
The control device is
Based on the value of the hydraulic pressure of the hydraulic cylinder acquired from the hydraulic pressure sensor for the cylinder, it is determined whether or not the suspended load work cycle, which is a series of operations for the suspended load, has been performed.
When it is determined that the suspended load work cycle has been performed, the operating state of the plurality of winches in the suspended load work cycle is acquired from the detection means, and the work input to the safety device acquired from the safety device is performed. Determining if the winch corresponding to the type was activated in the suspended load work cycle,
If it is determined that the operation has not been performed, it is determined that the type of work input to the safety device is incorrect, and the operation is determined to be incorrect.
A pump hydraulic sensor configured to detect the pressure of hydraulic oil discharged from the hydraulic pump and connected to the control device is further provided.
The control device is
From the operating state of the plurality of winches in the suspended load work cycle acquired from the detection means, it is determined whether or not any of the plurality of winches independently winds the wire rope in the suspended load work cycle. ,
When it is determined that the wire rope has been wound, it is determined whether or not the winch obtained from the safety device matches the winch corresponding to the type of work input to the safety device.
If they do not match, the pressure of the hydraulic oil acquired from the hydraulic pressure sensor for the pump is smaller than the predetermined threshold value at the time of winding the wire rope, or the pressure of the hydraulic oil acquired from the hydraulic pressure sensor for the pump is the predetermined value. When the state of the threshold value or more is less than the predetermined time, it is determined that the type of work input to the safety device is correct, and the pressure of the hydraulic oil acquired from the hydraulic pressure sensor for the pump is equal to or higher than the predetermined threshold value. When the state continues for the predetermined time or more, it is determined that the type of work input to the safety device is incorrect.
crane.

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