JP2023057882A - Backward rotation restraint device - Google Patents

Abstract

To control a hydraulic cylinder pressure to an appropriate magnitude corresponding to the condition of an undulating member for restraining the backward rotation of the undulating member.SOLUTION: A backward rotation restraint device 20 comprises a hydraulic cylinder 35, a condition monitoring unit 71, and a cylinder pressure control unit 60. The hydraulic cylinder 35 exerts a force in a direction (D1) to rotate an undulating member (13) forward X1 on the undulating member (13). The condition monitoring unit 71 monitors the condition of the undulating member (13) including a constitution length and a derricking angle (θ). The cylinder pressure control unit 60 controls the pressure of the hydraulic cylinder 35 based on the condition of the undulating member (13) monitored by the condition monitoring unit 71.SELECTED DRAWING: Figure 2

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tilting suppression device for a hoisting member.

For example, Japanese Laid-Open Patent Publication No. 2002-100002 describes a conventional tilting suppressing device for a hoisting member. In the technique described in the document, the thrust of the hydraulic cylinder is used to suppress the tilting (rearward rotation) of the hoisting member. In the technique described in the same document, the pressure of the hydraulic cylinder is set according to the moment acting on the hoisting member in the direction in which the hoisting member rotates rearward (the reversal moment in the same document).

JP-A-5-278995

In the invention described in the document, the pressure of the hydraulic cylinder may not be appropriate depending on the state of the hoisting member. Therefore, it is desired that the pressure of the hydraulic cylinder is controlled to an appropriate magnitude corresponding to the state of the hoisting member.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a tilting suppressing device capable of controlling the pressure of a hydraulic cylinder for suppressing tilting of a lifting member to an appropriate magnitude corresponding to the state of the lifting member. .

The fanning suppression device includes a hydraulic cylinder, a state monitoring section, and a cylinder pressure control section. The hydraulic cylinder applies a force to the hoisting member to rotate the hoisting member forward. The condition monitoring unit monitors the condition of the hoisting members, including configuration length and hoisting angle. The cylinder pressure control section controls the pressure of the hydraulic cylinder based on the state of the hoisting member monitored by the state monitoring section.

With the above configuration, it is possible to control the pressure of the hydraulic cylinder for suppressing the tilting of the hoisting member to an appropriate magnitude corresponding to the state of the hoisting member.

It is the figure which looked at the crane 1 from the horizontal direction Y. FIG. 2 is a view of a tilt suppressing member 30 and the like of the tilt suppressing device 20 shown in FIG. FIG. 3 is a view equivalent to FIG. 2 showing a state in which the boom 13 shown in FIG. 2 is rotated to a lodging side D1 from the state shown in FIG. 2; FIG. 3 is a hydraulic circuit diagram showing a hydraulic circuit section 50 of the tilt suppression device 20 shown in FIG. 2 ; FIG. 3 is a block diagram showing an electronic circuit unit 70 and the like of the tilt suppressing device 20 shown in FIG. 2; FIG. 5 is a view equivalent to FIG. 4 showing the hydraulic circuit section 50 of the tilting suppressing device 220 of the second embodiment.

(First embodiment)
A crane 1 (see FIG. 1) of the first embodiment will be described with reference to FIGS. 1 to 5. FIG.

The crane 1, as shown in FIG. 1, is a construction machine that performs work using a boom 13 (raising member). The crane 1 includes a lower body 11, an upper revolving body 12, a boom 13, a boom hoisting device 14 (hoisting device), a jib 15 (hoisting member), a jib hoisting device 16 (hoisting device), and a sway suppressing device. 20 and.

The lower body 11 supports the upper revolving body 12 . The lower main body 11 is, for example, a lower traveling body that allows the crane 1 to travel, and may include crawlers or wheels. The crane 1 may be a crawler crane or a wheeled crane. The lower body 11 may not be movable. The crane 1 may also be a stationary crane without mobile means.

The upper revolving body 12 is rotatably mounted on the lower body 11 . The upper revolving body 12 supports the boom 13 so that it can rise and fall. The upper revolving body 12 includes a revolving frame 12a, an operator's cab 12b, and a counterweight 12c. The revolving frame 12a is a structure to which the boom 13 and the like are attached. The operator's cab 12b is a part where the operator can operate the crane 1. As shown in FIG. The counterweight 12c is a weight for balancing the crane 1 in the longitudinal direction X. As shown in FIG.

(direction)
A vertical direction Z is defined as the direction in which the rotating shaft of the upper rotating body 12 extends with respect to the lower body 11 . In the vertical direction Z, the side (orientation) from the lower main body 11 toward the upper revolving body 12 is defined as an upper side Z1, and the opposite side is defined as a lower side Z2. The direction in which the axis of rotation of the boom 13 for ups and downs with respect to the upper revolving body 12 extends is defined as a lateral direction Y. As shown in FIG. A direction perpendicular to each of the up-down direction Z and the lateral direction Y is defined as a front-back direction X. As shown in FIG. In the longitudinal direction X, the side from the counterweight 12c toward the attachment portion (boom support shaft 13f (see FIG. 2)) of the boom 13 to the revolving frame 12a is defined as the front side X1, and the opposite side is defined as the rear side X2.

As shown in FIG. 2, the boom 13 (raising member) is attached to the upper revolving body 12 (more specifically, the revolving frame 12a) so as to be able to move up and down around the boom support shaft 13f. A central axis of the boom 13 extending in the longitudinal direction of the boom 13 is defined as a boom central axis 13a. The angle formed by the longitudinal direction X and the boom central axis 13a is defined as a boom hoisting angle θ. As shown in FIG. 1, the boom 13 includes a boom ventral surface 13g, a boom back surface 13h, and a boom side surface 13i. The boom flank 13g is a surface on the front side X1 of the boom 13 when the boom 13 is raised (for example, when the boom hoisting angle θ is 90 degrees). The boom back surface 13h is a surface on the rear side X2 of the boom 13 when the boom 13 is raised. The boom side surface 13i is a surface (side surface) that connects the boom rear surface 13h and the boom abdominal surface 13g and is arranged on the outer side in the lateral direction Y of the boom 13 .

This boom 13 may be disassembled in the longitudinal direction of the boom 13 . In this case, the boom 13 includes a lower boom 13l, an intermediate boom 13m, and an upper boom 13n. The lower boom 13l is arranged at the base end of the boom 13 (the end on the upper swing body 12 side). The intermediate boom 13m is connected to the tip of the lower boom 13l (the end opposite to the upper swing body 12 side). A plurality of intermediate booms 13m may be provided (may be added), only one may be provided, or none may be provided. The upper boom 13n is connected to the tip of the intermediate boom 13m and arranged at the tip of the boom 13 . The upper boom 13n may be a substantially hexahedral member (boom head, tower cap) or a member provided so as to extend in the longitudinal direction of the boom 13 . The boom 13 may be telescopic in the longitudinal direction of the boom 13 . The boom 13 may have a lattice structure or may have a box structure.

The undulating direction of the boom 13, more specifically, the direction of rotation around the boom support shaft 13f shown in FIG. The lodging side D1 is the direction in which the raised boom 13 rotates to the front side X1, and the boom hoisting angle θ decreases. The reversal side D2 (raising side) is the direction in which the raised boom 13 rotates to the rear side X2, and is the direction in which the boom hoisting angle θ increases.

The boom hoisting device 14 (hoisting device) is, as shown in FIG. The boom hoisting device 14 applies to the boom 13 a force on the reversal side D<b>2 (a force directed to rotate the boom 13 to the rear side X<b>2 ). For example, the boom luffing device 14 includes a gantry 14a, a boom luffing lower spreader 14b, a boom luffing upper spreader 14c, a boom guy line 14d, a boom luffing rope 14e, and a boom luffing winch 14f. The gantry 14 a includes a compression member 14 a 1 attached to the upper rotating body 12 and a tension member 14 a 2 connected to the tip of the compression member 14 a 1 and the rear X2 end of the upper rotating body 12 . The boom hoisting lower spreader 14b is a device having a plurality of sheaves and is provided at the tip of the compression member 14a1. The boom hoisting upper spreader 14 c is a device having a plurality of sheaves and is arranged between the tip of the compression member 14 a 1 and the tip of the boom 13 . The boom guy line 14 d is connected to the boom hoisting upper spreader 14 c and the tip of the boom 13 . The boom guy line 14d may include a rope (pendant rope) or a link member. The boom hoisting rope 14e is a rope that is hung on the sheave of the boom hoisting lower spreader 14b and the sheave of the boom hoisting upper spreader 14c. The boom hoisting winch 14f is a winch mounted on the upper rotating body 12, for example. A boom hoisting winch 14f reels in and pays out a boom hoisting rope 14e. Then, the distance between the boom hoisting lower spreader 14b and the boom hoisting upper spreader 14c changes. Since the boom hoisting upper spreader 14c and the tip of the boom 13 are connected by the boom guy line 14d, when the distance between the boom hoisting lower spreader 14b and the boom hoisting upper spreader 14c is changed, the boom 13 is moved with respect to the upper rotating body 12. undulates.

The configuration of the boom hoisting device 14 can be changed in various ways. For example, instead of the gantry 14a, a mast (not shown) may be provided. In this case, the mast is attached to the upper revolving body 12 so as to be able to rise and fall, and is arranged at the same position as the compression member 14a1. In this case, the boom hoisting rope 14e may be hung on a sheave provided at the rear end of the upper rotating body 12 and a sheave provided at the tip of the mast. Then, when the boom hoisting winch 14f reels in and pays out the boom hoisting rope 14e, the mast may hoist and hoist relative to the upper rotating body 12, resulting in the hoisting and lowering of the boom 13 relative to the upper rotating body 12.

A jib 15 (raising member) is attached to the boom 13 so as to be able to hoist around a jib support shaft 15a. The jib 15 may be dismantled in the longitudinal direction of the jib 15 . In this case, the jib 15 comprises a lower jib 15l, an intermediate jib 15m and an upper jib 15n. The lower jib 15l is arranged at the base end of the jib 15 (the end on the boom 13 side). The intermediate jib 15m is connected to the tip of the lower jib 15l (the end opposite to the boom 13 side). Only one intermediate jib 15m may be provided, a plurality of intermediate jibs may be provided, or no intermediate jib 15m may be provided. The upper jib 15 n is connected to the tip of the intermediate jib 15 m and arranged at the tip of the jib 15 .

The jib hoisting device 16 (hoisting device) is a device that hoists the jib 15 with respect to the boom 13 . The jib hoisting device 16 applies a force to the jib 15 to rotate the jib 15 to the rear side X2 (raise the jib 15 and increase the angle of the jib 15 with respect to the boom 13). For example, the jib luffing device 16 includes a strut 16a, a jib luffing line 16b, a strut guy line 16c, a jib luffing lower spreader 16d, a jib luffing upper spreader 16e, a jib luffing rope 16f, and a jib luffing winch 16g. The strut 16a (rear strut 16a1, front strut 16a2) is rotatably attached to the tip of the boom 13. As shown in FIG. The front strut 16a2 is arranged on the front side X1 of the rear strut 16a1 when the crane 1 is in a workable posture (crane posture). The jib guy line 16 b is connected to the tip of the front strut 16 a 2 and the tip of the jib 15 . The jib luffing lower spreader 16d comprises a plurality of sheaves and is attached to the boom 13, for example. The boom luff upper spreader 14c includes a plurality of sheaves and is positioned between the rear strut 16a1 and the jib luff lower spreader 16d. The jib luffing rope 16f is looped over the sheave of the jib luffing lower spreader 16d and the sheave of the jib luffing upper spreader 16e. The jib hoisting winch 16g is a winch mounted on the upper revolving structure 12 or the boom 13 . A jib luffing winch 16g reels in and pays out a jib luffing rope 16f. Then, the distance between the jib undulating lower spreader 16d and the jib undulating upper spreader 16e changes. Then, the strut 16 a rises and falls (rotates) with respect to the boom 13 . Since the tip of the front strut 16a2 and the tip of the jib 15 are connected by the jib guy line 16b, when the front strut 16a2 rises and falls relative to the boom 13, the jib 15 rises and falls relative to the boom 13.

The configuration of the jib hoisting device 16 can be changed in various ways. For example, the boom hoisting rope 14e may be hung between the sheave provided on the front strut 16a2 and the sheave provided on the rear strut 16a1. Then, when the jib hoisting winch 16g winds up and lets out the jib hoisting rope 16f, the distance between the front strut 16a2 and the rear strut 16a1 changes, and as a result, the jib 15 may hoist with respect to the boom 13. Alternatively, only one strut 16a may be provided.

When the crane 1 is provided with the jib 15, the crane 1 may be a tower crane in which the jib 15 is raised and lowered without the boom 13 being raised and lowered during operation of the crane 1, and the boom 13 and the jib 15 are raised and lowered during operation of the crane 1. A luffing crane may also be used. When the crane 1 is working, the jib 15 does not have to rise and fall. Also, the crane 1 does not have to include the jib 15 and the jib luffing device 16 .

The tilting suppression device 20 is a device that suppresses rotation (tilting) of at least one of the boom 13 and the jib 15 (raising member) to the rear side X2 (to the reverse side D2). In the following, the case where the boom 13 is mainly the hoisting member that is subject to the tilting suppression by the tilting suppression device 20 will be described. The fanning suppressing device 20 suppresses the boom 13 from being fanned to the reversing side D2 by applying (pulling back) the force to rotate the boom 13 to the lofting side D1. For example, the boom 13 may be fanned toward the reverse side D2 due to wind load. For example, the boom 13 may be tilted toward the reversal side D2 due to swinging of the lower body 11 and the upper rotating body 12 in the front-rear direction X, or the like. The tilt suppression device 20 includes a tilt suppression member 30 and a cylinder control circuit 40 (see FIGS. 4 and 5).

As shown in FIG. 2, the tilting suppression member 30 is attached to the hoisting member (here, the boom 13) that is subject to tilting suppression. The fanning suppressing member 30 is attached to the upper rotating body 12 and the boom 13 . For example, the tilt suppressing members 30 are provided on both sides (left and right) in the horizontal direction Y of the upper rotating body 12 . In FIG. 2 and the like, only one of the tilt suppressing members 30 on both sides in the horizontal direction Y is illustrated. Only one fanning suppression member 30 may be provided. It is preferable that the position of the front side X1 end of the tilt suppressing member 30 in the front-rear direction X is the same position as the position of the front end of the lower body 11 in the front-rear direction X, or arranged on the rear side X2. This arrangement preferably holds regardless of the angle of rotation of the upper rotating body 12 with respect to the lower body 11 . In this case, when the upper revolving body 12 revolves with respect to the lower main body 11, interference between objects around the crane 1 and the tilt suppression member 30 is suppressed. In addition, the front side X1 end portion of the tilt suppressing member 30 may be arranged on the front side X1 with respect to the tip portion of the lower body 11 . The tilting suppressing member 30 includes a lower member 31 , an upper member 32 , a connecting member 37 and a holder 39 .

The lower member 31 constitutes the lower side Z2 portion of the tilt suppressing member 30 . The lower member 31 is attached to the front side X1 portion of the upper revolving body 12 so as to be rotatable in the vertical direction Z. As shown in FIG. The horizontal direction Y is the direction in which the rotation axis of the lower member 31 with respect to the upper revolving body 12 extends. A portion where the lower member 31 is attached to the upper revolving body 12 is referred to as a lower member base end portion 31f. The lower member base end portion 31f is provided on the rear side X2 portion of the lower member 31 (for example, the rear side X2 end portion). For example, the lower member proximal end 31f is attached to the front X1 portion (for example, the front X1 end) of the swing frame 12a. The lower member proximal end 31f is attached to the lower Z2 portion (for example, the lower Z2 end) of the revolving frame 12a. The lower member 31 is arranged to protrude from the front side X1 portion of the revolving frame 12a toward the front side X1. The lower member 31 is, for example, columnar (stay, lower stay).

The upper member 32 is arranged above the lower member 31 Z1. The upper member 32 is attached to the front side X1 portion of the upper revolving body 12 so as to be rotatable in the vertical direction Z. As shown in FIG. The horizontal direction Y is the direction in which the rotation axis of the upper member 32 extends with respect to the upper revolving body 12 . An attachment portion of the upper member 32 to the upper revolving body 12 is referred to as an upper member base end portion 32f. The upper member base end portion 32f is provided on the rear side X2 portion of the upper member 32 (for example, the rear side X2 end portion). The upper member base end portion 32f is attached to the front side X1 portion of the upper revolving body 12 . The upper member base end portion 32f is attached to a portion of the upper revolving body 12 that is above the lower member base end portion 31f. The upper member base end portion 32f is arranged on the upper side Z1 than the lower member base end portion 31f. The larger the distance between the lower member proximal end portion 31f and the upper member proximal end portion 32f (more specifically, the distance in the vertical direction Z), the more preferable it is dynamically. For example, upper member proximal end 32f is preferably attached to the upper Z1 portion (eg, upper Z1 end) of pivot frame 12a. For example, the upper member base end portion 32f is preferably attached to the attachment portion (boom support shaft 13f) of the boom 13 to the upper rotating body 12. As shown in FIG. The position of the upper member base end portion 32f in the front-rear direction X may be the rear side X2, the same position, or the front side X1 with respect to the position in the front-rear direction X of the lower member base end portion 31f. The upper member 32 is arranged to protrude from the front side X1 portion of the swing frame 12a toward the front side X1. The upper member 32 is arranged inclined in the front-rear direction X so as to be arranged on the lower side Z2 toward the front side X1.

This upper member 32 is connected to the lower member 31 . The upper member 32 is rotatably connected to a portion of the lower member 31 that is different from the lower member base end portion 31f. A connecting portion between the upper member base end portion 32f and the lower member base end portion 31f is referred to as an upper and lower member connecting portion 32t. For example, the upper and lower member connecting portion 32t is provided at the front side X1 portion of the upper member 32 (for example, the front side X1 end portion). The upper and lower member connecting portion 32t is provided at the end portion of the lower member 31 opposite to the lower member base end portion 31f, for example, at the front side X1 portion of the lower member 31 (for example, the front side X1 end portion). The upper member 32 has an upper stay 33 and a hydraulic cylinder 35 .

The upper stay 33 and the hydraulic cylinder 35 are arranged in series. The upper stay 33 and the hydraulic cylinder 35 can be arranged in various ways. For example, the hydraulic cylinder 35 may be arranged on the front side X1 of the upper stay 33, may be arranged on the rear side X2 of the upper stay 33, and may be arranged so as to be sandwiched between the upper stays 33 in the front-rear direction X. may A case where the hydraulic cylinder 35 is arranged on the front side X1 of the upper stay 33 will be mainly described below.

The upper stay 33 is a columnar member. In the example shown in FIG. 2, the rear end of the upper stay 33 is the upper member base end 32f.

The hydraulic cylinder 35 applies a force to the boom 13 in a direction to rotate the boom 13 toward the front side X1 (the lodging side D1). The hydraulic cylinder 35 is extendable. The expansion and contraction direction of the hydraulic cylinder 35 is the direction in which the upper member 32 extends (longitudinal direction of the upper member 32). The hydraulic cylinder 35 is attached to the upper stay 33 and fixed to the upper stay 33 . The hydraulic cylinder 35 and the upper stay 33 are arranged (connected) in series. Therefore, the force transmitted from the hydraulic cylinder 35 to the upper stay 33 can be reliably (effectively) supported by the upper stay 33 . More specifically, the extension/contraction direction of the hydraulic cylinder 35 matches or substantially matches the longitudinal direction of the upper stay 33 . The central axis of the hydraulic cylinder 35 (the central axis extending in the telescopic direction of the hydraulic cylinder 35) and the central axis of the upper stay 33 (the central axis extending in the longitudinal direction of the upper stay 33) are coaxial or substantially coaxial. The hydraulic cylinder 35 includes a cylinder tube 35a and a cylinder rod 35b.

The cylinder tube 35a includes a bottom chamber 35a1 (see FIG. 4) to which pressure oil is supplied. The hydraulic pressure in the bottom chamber 35a1 is called "pressure of the hydraulic cylinder 35". The cylinder rod 35b is inserted into the cylinder tube 35a. The cylinder rod 35b moves relative to the cylinder tube 35a by supplying pressurized oil to the cylinder tube 35a (more specifically, the bottom chamber 35a1). The tip of the cylinder rod 35b may be arranged on the front side X1 of the cylinder tube 35a, or may be arranged on the rear side X2 of the cylinder tube 35a. In the example shown in FIG. 2, the tip portion (front side X1 end portion) of the cylinder rod 35b is the upper and lower member connecting portion 32t. In this example, the rear X2 end of the cylinder tube 35 a is attached to the front X1 end of the upper stay 33 . Note that the tip of the cylinder rod 35b may be attached to the upper revolving body 12 (or the base end of the upper member 32f). The end (bottom) of the cylinder tube 35a on the side opposite to the cylinder rod 35b may be attached to the upper revolving body 12 (it may be the upper member base end 32f), or may be attached to the lower member 31. (The upper and lower member connecting portions 32t may be used).

The connecting member 37 transmits the thrust of the hydraulic cylinder 35 to the boom 13 . The connecting member 37 is connected to at least one of the lower member 31 and the upper member 32 and the boom 13 . The lower Z2 end of the connecting member 37 (more specifically, the lower Z2 end of the connecting member 37 in a linearly stretched state) is connected to the lower member 31 and the upper member 32 . A lower Z2 end of the connection member 37 is connected to the lower member 31 and the upper member 32 at a position on the front side X1 of the boom support shaft 13f. For example, the connecting member 37 is connected to the upper and lower member connecting portion 32t. The connecting member 37 may be connected to the lower member 31 and the upper member 32 at positions different from the upper and lower member connecting portions 32t. The connecting member 37 does not have to be directly connected to the lower member 31 . For example, the connecting member 37 may be directly connected to the upper member 32 and connected to the lower member 31 via the upper member 32 and the upper and lower member connecting portions 32t. The connecting member 37 does not have to be directly connected to the upper member 32 . For example, the connecting member 37 may be directly connected to the lower member 31 and connected to the upper member 32 via the lower member 31 and the upper and lower member connecting portions 32t.

The upper Z1 end of this connecting member 37 is connected to the boom 13 . For example, the upper Z1 end of connecting member 37 may be connected to lower boom 13l, to middle boom 13m shown in FIG. 1, or to upper boom 13n. The upper Z1 end of the connection member 37 shown in FIG. 2 may be connected to the boom ventral surface 13g, the boom side surface 13i, or the boom back surface 13h. For example, when the upper Z1 end of the connection member 37 is connected to the lower boom 13l, the upper Z1 end of the connection member 37 may be connected to the tip of the lower boom 13l.

The connection member 37 is, for example, a tension member, and specifically, may be a rope (pendant rope), a foldable link member, or the like. Here, when the fanning suppression member 30 is arranged on the rear side X2 of the boom support shaft 13f, the fanning suppression member 30 pushes the boom 13 forward X1 in order to apply the force of the falling side D1 to the boom 13. need arises. Therefore, it is necessary to use, for example, a rod-like structure as a member (connection member 37 in this embodiment) that transmits the force of the hydraulic cylinder 35 to the boom 13, and a tension member cannot be used. Therefore, the tilt suppressing member 30 may become large. On the other hand, in the present embodiment, the fanning suppression member 30 is arranged on the front side X1 of the boom support shaft 13f. Therefore, the connection member 37 pulls the boom 13 to the lower side Z2, so that the force of the lofting side D1 can be applied to the boom 13. As shown in FIG. Therefore, a tension member can be used as the connecting member 37 . As a result, the tilt suppressing member 30 can be configured compactly. As a modification, the fanning suppression member 30 may be arranged on the rear side X2 of the boom support shaft 13f.

The holder 39 is a member for holding (supporting) the connection member 37 with respect to the boom 13 when the connection member 37 is a hanging member such as a rope, as shown in FIG. The retainer 39 prevents the connection member 37 from hanging down below the lower member 31 when the boom hoisting angle θ is less than or equal to a certain angle. For example, the retainer 39 prevents the connecting member 37 from sagging downward Z2 below the lower member 31 or limits the amount of sagging downward Z2 of the connecting member 37 relative to the lower member 31 . The holder 39 is provided to connect (clamp) the boom 13 and the connection member 37 . The retainer 39 may be attached to the lower boom 13l, may be attached to the intermediate boom 13m shown in FIG. 1, or may be attached to the upper boom 13n. The holder 39 shown in FIG. 2 may be attached to the boom ventral surface 13g, the boom side surface 13i, or the boom back surface 13h. The retainer 39 biases the connection member 37 in a direction to bring the connection member 37 closer to the boom 13 . The holder 39 is, for example, spring-shaped.

The cylinder control circuit 40 is a circuit that controls the hydraulic cylinder 35, as shown in FIG. The cylinder control circuit 40 is mounted, for example, on the upper revolving body 12 (see FIG. 1). The cylinder control circuit 40 includes a hydraulic circuit section 50 and an electronic circuit section 70 (see FIG. 5).

The hydraulic circuit section 50 is a hydraulic circuit for controlling the hydraulic cylinder 35 . The hydraulic circuit unit 50 includes a hydraulic pump 51 , a pressure oil supply path 52 , a pressure oil supply on/off valve 53 , a check valve 54 , an accumulator 55 , a cylinder pressure control on/off valve 56 , and a crane stop relief valve 57 . , a pressure source 58 and a cylinder pressure control unit 60 .

The hydraulic pump 51 discharges pressure oil supplied to the hydraulic cylinder 35 .

The pressure oil supply path 52 is a pipeline (oil path, piping) that connects the hydraulic pump 51 and the hydraulic cylinder 35 . The pressure oil supply path 52 is a conduit for supplying pressure oil from the hydraulic pump 51 to the hydraulic cylinder 35 .

The pressure oil supply on/off valve 53 is a valve (switch valve) that switches whether to supply pressure oil from the hydraulic pump 51 to the hydraulic cylinder 35 . The pressure oil supply on/off valve 53 is provided in the pressure oil supply path 52 and is provided between the hydraulic pump 51 and the hydraulic cylinder 35 (in the pipeline, the same applies hereinafter). The pressure oil supply on/off valve 53 is, for example, an electromagnetic switching valve, and is switched according to commands (electrical signal, on signal, off signal) from a control section 73 (see FIG. 5), which will be described later. The pressure oil supply on/off valve 53 has a pressure oil supply on position 53a and a pressure oil supply off position 53b. The pressure oil supply ON position 53 a is selected when pressure oil is supplied from the hydraulic pump 51 to the hydraulic cylinder 35 . The pressure oil supply OFF position 53b is selected when the pressure oil is not supplied from the hydraulic pump 51 to the hydraulic cylinder 35 .

The check valve 54 is a valve for holding the pressure of the hydraulic cylinder 35 (and the pressure of the pressure oil supply path 52). A check valve 54 is provided in the pressure oil supply path 52 . The check valve 54 is configured to allow oil to flow from the hydraulic pump 51 to the hydraulic cylinder 35 without allowing oil to flow from the hydraulic cylinder 35 to the tank 50t.

The accumulator 55 is provided in the pressure oil supply path 52 and stabilizes the hydraulic pressure in the pressure oil supply path 52 .

The cylinder pressure control on/off valve 56 is a valve (switch valve, open/close valve) that switches whether or not the cylinder pressure control unit 60 controls the pressure of the hydraulic cylinder 35 . A cylinder pressure control on/off valve 56 is provided in the pressure oil supply path 52 and provided between the hydraulic cylinder 35 and the cylinder pressure control section 60 . The cylinder pressure control on/off valve 56 is, for example, an electromagnetic opening/closing valve, and is switched according to a command (electrical signal) from a control section 73 (see FIG. 5), which will be described later. Cylinder pressure control on/off valve 56 has a control off position 56a and a control on position 56b. The control off position 56a is selected when the pressure of the hydraulic cylinder 35 is not controlled by the cylinder pressure control section 60. FIG. The control-on position 56b is selected when the pressure of the hydraulic cylinder 35 is controlled by the cylinder pressure control section 60. FIG. For example, when the crane 1 is working, the control-on position 56b is selected. For example, the control ON position 56b is selected when a remote control valve (such as an operating lever) for operating the crane 1 is operated. For example, the control off position 56a is selected at times other than crane operations. The timing at which the pressure of the hydraulic cylinder 35 is controlled by the cylinder pressure control section 60 can be set variously.

The crane stop relief valve 57 is a valve that sets the maximum pressure of the hydraulic cylinder 35 (of the pressure oil supply path 52), and prevents the pressure of the hydraulic cylinder 35 from becoming excessively high. When the pressure of the hydraulic cylinder 35 tends to become higher than the set pressure of the crane stop relief valve 57, the crane stop relief valve 57 causes oil to flow from the hydraulic cylinder 35 to the tank 50t. The set pressure of the relief valve 57 when the crane is stopped is higher than the set pressure of the cylinder pressure setting valve 61, which will be described later.

The pressure source 58 is a hydraulic pressure source (primary pressure source) for a set pressure change valve 63, which will be described later, and is, for example, a hydraulic pump.

A cylinder pressure control unit 60 controls the pressure of the hydraulic cylinder 35 . The cylinder pressure control unit 60 is provided in the pressure oil supply path 52 and provided between the hydraulic cylinder 35 and the tank 50t. The cylinder pressure control unit 60 controls the pressure of the hydraulic cylinder 35 based on the state of the boom 13 (see FIG. 1) monitored by the state monitoring unit 71 (see FIG. 5) described later (details will be described later). For example, the cylinder pressure control section 60 may be configured to be able to continuously (steplessly) change the pressure of the hydraulic cylinder 35 . For example, the cylinder pressure control section 60 may be configured to be able to change the pressure of the hydraulic cylinder 35 stepwise (non-continuously) (see FIG. 6). Here, a case where the cylinder pressure control unit 60 is configured to be able to continuously change the pressure of the hydraulic cylinder 35 will be described. For example, the cylinder pressure control section 60 includes a cylinder pressure setting valve 61 and a set pressure change valve 63 .

The cylinder pressure setting valve 61 is a valve that sets the pressure of the hydraulic cylinder 35 . The cylinder pressure setting valve 61 is provided in the pressure oil supply path 52 and provided between the hydraulic cylinder 35 and the tank 50t. For example, the cylinder pressure setting valve 61 is a relief valve and sets the maximum pressure of the hydraulic cylinder 35 . In this case, when the pressure of the hydraulic cylinder 35 tries to become higher than the set pressure (relief pressure) of the cylinder pressure setting valve 61, the cylinder pressure setting valve 61 causes oil to flow from the hydraulic cylinder 35 to the tank 50t. The set pressure of the cylinder pressure setting valve 61 is continuously variable. The set pressure of the cylinder pressure setting valve 61 may be set by hydraulic pressure (pilot pressure) (or may be of a hydraulic pilot type), or may be set according to an electric signal. A case where the set pressure of the cylinder pressure setting valve 61 is set by the pilot pressure will be mainly described below.

The set pressure change valve 63 is a valve that sets the set pressure of the cylinder pressure setting valve 61 . The set pressure change valve 63 is connected to the pressure source 58 (temporary pressure source). The set pressure change valve 63 is connected to the cylinder pressure set valve 61 . The set pressure changing valve 63 changes the set pressure of the cylinder pressure setting valve 61 according to a command (electrical signal) from a control section 73 (see FIG. 5) which will be described later. The set pressure change valve 63 is, for example, an electromagnetic proportional valve, such as an electromagnetic pressure reducing valve. For example, the set pressure change valve 63 changes the pilot pressure (secondary pressure) output to the cylinder pressure set valve 61 according to a command from the control section 73 . For example, the set pressure change valve 63 reduces the hydraulic pressure input from the pressure source 58 to the set pressure change valve 63 according to an electric signal input to the set pressure change valve 63 and outputs the hydraulic pressure to the cylinder pressure setting valve 61 . . Note that the cylinder pressure control section 60 may be configured by one valve. For example, the set pressure change valve 63 may not be provided, and the set pressure of the cylinder pressure setting valve 61 may be set according to the command from the control section 73 .

The electronic circuit section 70 (see FIG. 5) is an electronic circuit for controlling the hydraulic cylinder 35 . As shown in FIG. 5 , the electronic circuit section 70 includes a state monitoring section 71 and a control section 73 .

The state monitoring unit 71 monitors the state of the hoisting members (the boom 13 and the jib 15). 1 is the boom 13 and the jib 15 is not provided on the boom 13, the condition monitoring unit 71 (see FIG. 1) is the boom 13. 5) monitors the condition of the boom 13. When the target hoisting member is the boom 13 and the jib 15 is provided on the boom 13, the state monitoring unit 71 may monitor the state of the boom 13 only, and the states of the boom 13 and the jib 15 may be monitored. is preferably monitored. When the target hoisting member is the jib 15 , the state monitoring section 71 may monitor the state of the jib 15 only, and preferably monitors the states of the boom 13 and the jib 15 . When the target hoisting members are the boom 13 and the jib 15 , the state monitoring section 71 monitors the states of the boom 13 and the jib 15 .

A case where the state monitoring unit 71 (see FIG. 5) monitors the state of the boom 13 shown in FIG. 1 will be described below. The state of the boom 13 monitored by the state monitoring unit 71 includes at least the structural length of the boom 13 (length of the boom 13 in the axial direction) and the boom hoisting angle θ. The state of the boom 13 monitored by the state monitoring unit 71 (see FIG. 5) may include the state of the moment (moment of force) acting on the boom 13 on the reverse side D2. "The state of the moment of the reversing side D2 acting on the boom 13" may include the load acting on the boom hoisting device 14, for example. Information on the structural length of the boom 13 , the boom hoisting angle θ, and the load acting on the boom hoisting device 14 is information obtained by an overload prevention device that is normally equipped on the crane 1 . Therefore, the state monitoring unit 71 (see FIG. 5) may obtain information on the state of the boom 13 by using information possessed by the overload prevention device. Note that the state monitoring unit 71 may acquire information on the state of the boom 13 without using the information on the overload prevention device. As shown in FIG. 5, the state monitoring unit 71 includes a configuration length acquiring unit 71a, an angle acquiring unit 71b, and a hoisting device load acquiring unit 71c.

The configuration length acquisition unit 71a acquires information on the configuration length of the boom 13 shown in FIG. For example, if the boom 13 can be disassembled in the axial direction (additional type), the type and number of the lower boom 13l, intermediate boom 13m, and upper boom 13n are set in the configuration length acquisition unit 71a (see FIG. 5). be done. Then, the configuration length acquisition unit 71 a may determine the configuration length of the boom 13 based on the set information of the boom 13 . For example, if the boom 13 is of a telescopic type, the structural length acquisition unit 71 a may acquire the structural length of the boom 13 from the detection result of a length gauge (not shown) provided on the boom 13 .

The angle acquisition unit 71b (see FIG. 5) acquires the hoisting angle (boom hoisting angle θ) of the boom 13 shown in FIG. For example, the angle acquisition unit 71b (see FIG. 5) may acquire the boom hoisting angle θ from the detection result of an angle sensor provided on the boom support shaft 13f (see FIG. 2). The boom hoisting angle θ may be acquired from the detection result of the sensor.

The hoisting device load acquisition unit 71 c (see FIG. 5 ) (moment information acquisition unit) acquires the state of the moment acting on the boom 13 on the reverse side D<b>2 . Specifically, the hoisting device load acquisition unit 71 c acquires the load acting on the boom hoisting device 14 . The load acting on the boom hoisting device 14 (load acting on the hoisting device) is included in the state of the boom 13 (state of the hoisting member). More specifically, for example, the hoisting device load acquisition unit 71c may acquire the detected value of the tension of the boom hoisting rope 14e. The tension of the boom hoisting rope 14e may be detected by, for example, a load cell or the like, and may be obtained by detecting the force acting on the sheave on which the boom hoisting rope 14e is hung. It may be obtained by being detected. The hoisting device load acquisition unit 71c may acquire the detected value of the tension acting on the boom guy line 14d. Note that when the tilting suppressing device 20 suppresses tilting of the jib 15 , the hoisting device load acquisition unit 71 c acquires the load acting on the jib hoisting device 16 . In this case, the hoisting device load acquisition unit 71c may acquire the tension of the jib hoisting rope 16f, the jib guy line 16b, or the strut guy line 16c, or may acquire the force acting on the boom hoisting winch 14f.

The control unit 73 (see FIG. 5) performs signal input/output, information storage, calculation, and the like. As shown in FIG. 5, the control unit 73 includes a storage unit 73a, a calculation unit 73b, and an output unit 73c.

The storage unit 73a stores information. The storage unit 73a stores information (information necessary for pressure control) for controlling the pressure of the hydraulic cylinder 35 (see FIG. 1) according to the state of the boom 13 (see FIG. 1). Specific contents of the information stored in the storage unit 73a will be described later. The storage unit 73a stores information necessary for pressure control of the hydraulic cylinder 35 for each state of the boom 13 shown in FIG. For example, the storage unit 73a stores information necessary for pressure control of the hydraulic cylinder 35 for each combination of the structural length of the boom 13 and the boom hoisting angle θ. More specifically, the storage unit 73a stores information necessary for pressure control of the hydraulic cylinder 35 for each of various boom hoisting angles θ of various structural lengths.

The calculation unit 73b determines the content of the instruction to the cylinder pressure control unit 60 based on the state of the boom 13 (see FIG. 1) monitored by the state monitoring unit 71 shown in FIG. For example, the computing unit 73b determines the required pressure of the hydraulic cylinder 35 (see FIG. 1) based on the state of the boom 13 monitored by the state monitoring unit 71. FIG. The specific content of the calculation by the calculation unit 73b will be described later.

The output unit 73c outputs a command (electrical signal) to the cylinder pressure control unit 60 (for example, the set pressure change valve 63) based on the content determined by the calculation unit 73b.

(activation)
Crane 1 (see FIG. 1) is configured to operate as follows.

(uncontrolled range)
When the boom hoisting angle θ shown in FIG. 3 is smaller than a predetermined angle (for example, 80 degrees), the moment on the lowering side D1 due to the weight of the boom 13 is sufficiently larger than the moment on the reversing side D2 due to wind load, for example. Therefore, the problem that the boom 13 is tilted toward the reverse side D2 is unlikely to occur. Therefore, when the boom hoisting angle θ is smaller than a predetermined range A (for example, a range of 80 degrees or more and 90 degrees or less) (for example, when it is less than 80 degrees), the tilting suppression device 20 suppresses the tilting of the boom 13. It may not be performed, and the control of the pressure of the hydraulic cylinder 35 may not be performed. Specifically, when the boom hoisting angle θ is smaller than the predetermined range A, the pressure oil supply on/off valve 53 shown in FIG. 5 is set (switched) to the pressure oil supply off position 53b. Then, pressure oil is not supplied from the hydraulic pump 51 to the hydraulic cylinder 35 . At this time, the cylinder pressure control on/off valve 56 may be in the control off position 56a.

(Control range)
When the boom hoisting angle θ shown in FIG. When the boom hoisting angle θ is within the predetermined range A, the pressure of the hydraulic cylinder 35 is controlled. At this time, the pressure oil supply on/off valve 53 shown in FIG. Cylinder pressure control on/off valve 56 is in control on position 56b.

When the boom hoisting angle θ is within the predetermined range A, the connection member 37 is stretched linearly. When the boom hoisting angle θ is within the predetermined range A, the lower member 31 and the upper member 32 rotate in the vertical direction Z with respect to the upper rotating body 12 as the boom 13 hoists. At this time, the hydraulic cylinder 35 expands and contracts as the lower member 31 and the upper member 32 rotate with respect to the upper revolving body 12 (see FIGS. 2 and 3).

The minimum angle Amin (for example, 80 degrees) of the predetermined range A of the boom hoisting angle θ shown in FIG. The hydraulic cylinder 35 is preferably set to be in the "extended state" when the boom hoisting angle θ is the minimum angle Amin. This "extended state" may be a fully extended state (a state in which the hydraulic cylinder 35 is most extended) or a substantially fully extended state. When the boom hoisting angle θ is increased from an angle smaller than the minimum angle Amin, it is preferable that the hydraulic cylinder 35 is fully extended immediately before reaching the minimum angle Amin or at the same time as reaching the minimum angle Amin. . When the boom hoisting angle θ is the minimum angle Amin, when the hydraulic cylinder 35 is extended, the stroke (extendable length) of the hydraulic cylinder 35 is suppressed from exceeding the required length, The hydraulic cylinder 35 can be downsized. When the boom hoisting angle θ is the minimum angle Amin, the tilting suppressing member 30 is configured such that the connecting member 37 is stretched (stretched) in a straight line.

The maximum angle Amax of the predetermined range A of the boom hoisting angle θ shown in FIG. For example, the maximum angle Amax may be equal to the maximum allowable hoisting angle of the boom 13 . The hydraulic cylinder 35 is set so as to be fully retracted when the boom hoisting angle θ is the maximum allowable hoisting angle. In this case, since the hydraulic cylinder 35 in the fully retracted state acts as a rod (holding bar), the rotation of the boom 13 to the reverse side D2 can be mechanically suppressed.

(Overview of Control of Pressure of Hydraulic Cylinder 35)
The pressure of hydraulic cylinder 35 is controlled according to the state of boom 13 . More specifically, the state monitoring unit 71 shown in FIG. 5 monitors the state of the boom 13 (see FIG. 2). The control unit 73 outputs a command to the cylinder pressure control unit 60 according to the state of the boom 13 monitored by the state monitoring unit 71 (the current state of the boom 13). Cylinder pressure control section 60 controls the pressure of hydraulic cylinder 35 shown in FIG. 2 based on the command from control section 73 . The hydraulic cylinder 35 always applies the force of the lofting side D<b>1 (the moment of the force of the lofting side D<b>1 ) to the boom 13 . For example, the moment of force on the reversal side D2 may act on the boom 13 due to factors other than the boom hoisting device 14 shown in FIG. 1 (wind load, etc.). Even in this case, since the moment of the force on the lowering side D1 by the hydraulic cylinder 35 shown in FIG.

(Specific example of pressure control of hydraulic cylinder 35)
Even for the same boom 13, the smaller the boom hoisting angle θ, the less likely the boom 13 will be tilted toward the lofting side D1 by the weight of the boom 13, and the greater the boom hoisting angle θ, the more likely the boom 13 will be tilted toward the lofting side D1. Therefore, it is preferable that the pressure of the hydraulic cylinder 35 is set higher as the boom hoisting angle θ increases. It is preferable that the smaller the boom hoisting angle θ, the lower the pressure of the hydraulic cylinder 35 is set.

Even if the boom hoisting angle θ is the same, the longer the structural length of the boom 13 is, the easier it is to receive the wind load, and the easier it is to be swayed toward the reversal side D2. Even if the boom hoisting angle θ is the same, the shorter the structural length of the boom 13 is, the less likely it is to receive the wind load and the less likely it is to be swayed by the lodging side D1. Therefore, it is preferable that the longer the structural length of the boom 13 is, the higher the pressure of the hydraulic cylinder 35 is set. It is preferable that the pressure of the hydraulic cylinder 35 is set lower as the structural length of the boom 13 is shorter.

Even with the same boom hoisting angle θ, the longer the structural length of the boom 13, the greater the inertial force of the boom 13, and once it starts rotating toward the reverse side D2, it is difficult to stop the rotation. Even if the boom hoisting angle θ is the same, the shorter the structural length of the boom 13, the smaller the inertial force of the boom 13, and the easier it is for the boom 13 to stop rotating even if it starts rotating toward the reverse side D2. Therefore, it is preferable that the longer the structural length of the boom 13 is, the higher the pressure of the hydraulic cylinder 35 is set. It is preferable that the pressure of the hydraulic cylinder 35 is set lower as the structural length of the boom 13 is shorter. Similarly, the larger the mass of the boom 13, the larger the force of inertia of the boom 13, and the smaller the mass of the boom 13, the smaller the force of inertia of the boom 13. Therefore, the pressure of the hydraulic cylinder 35 may be set higher as the mass of the boom 13 is larger, and the pressure of the hydraulic cylinder 35 may be set lower as the mass of the boom 13 is smaller. Further, the pressure of the hydraulic cylinder 35 may be set higher as the inertia coefficient of the boom 13 (boom inertia coefficient K described later) is larger, and the pressure of the hydraulic cylinder 35 may be set lower as the boom inertia coefficient K is smaller. .

As the pressure of the hydraulic cylinder 35 is increased, the tilting of the boom 13 toward the reverse side D2 can be suppressed. On the other hand, if the pressure of the hydraulic cylinder 35 is too high, energy is wasted and the load acting on the boom hoisting device 14 shown in FIG. 1 increases. Therefore, it is preferable to set the pressure of the hydraulic cylinder 35 so that the load acting on the boom hoisting device 14 can be suppressed and the tilting of the boom 13 toward the reverse side D2 can be suppressed. Therefore, it is preferable that the pressure of the hydraulic cylinder 35 is controlled based on the load acting on the boom hoisting device 14 .

For example, the pressure of the hydraulic cylinder 35 is preferably controlled so that the load acting on the boom hoisting device 14 is less than or equal to a "predetermined value". For example, the pressure of the hydraulic cylinder 35 is preferably controlled so that the tension T1, which will be described later, is equal to or less than the tension T0, which will be described later (or a value calculated based on the tension T0). The above-mentioned "load acting on the boom hoisting device 14" is the load (current load) acquired by the hoisting device load acquisition unit 71c (see FIG. 5). T1) and so on. The "predetermined value" may be, for example, the load (for example, tension T0) acting on the boom hoisting device 14 when the boom 13 having the same structural length and boom hoisting angle θ as the current boom 13 is in an unloaded state. The "predetermined value" may be a value calculated based on this load (for example, tension T0). The above-mentioned "no-load state" means, for example, that the boom 13 is not hoisting, that the boom 13 is not lifting a load, and that the boom 13 is not receiving wind load (or is receiving only a negligible degree). state, etc. The "predetermined value" or a value for calculating the "predetermined value" is stored in advance in the storage unit 73a (see FIG. 5) (described later).

For example, the pressure of the hydraulic cylinder 35 is a value ( For example, it may be a value obtained by multiplying a calculated value of pressure by a boom inertia coefficient K). The boom inertia coefficient K indicates the degree to which the boom 13 continues to rotate toward the reverse side D2 (ease of reversing) when the boom 13 rotates toward the reverse side D2. Specifically, the boom inertia coefficient K increases as the structural length of the boom 13 increases, and increases as the mass of the boom 13 increases. For example, when the boom inertia coefficient K is used to calculate the pressure of the hydraulic cylinder 35, the relationship between the boom hoisting angle θ and the boom inertia coefficient K is stored in the storage unit 73a (FIG. 5) for each configuration length of the boom 13. ) may be pre-stored.

Note that when the tilting suppressing device 20 suppresses tilting of the jib 15 , it is preferable that the pressure of the hydraulic cylinder 35 is controlled based on the load acting on the jib hoisting device 16 . For example, the pressure of the hydraulic cylinder 35 for suppressing the tilting of the jib 15 may be controlled so that the load acting on the jib hoisting device 16 is equal to or less than the "second predetermined value". The "second predetermined value" is, for example, the load acting on the jib hoisting device 16 when the boom 13 and jib 15 are in an unloaded state. Further, for example, for the pressure of the hydraulic cylinder 35 for suppressing the swaying of the jib 15, the calculated value of the pressure at which the load acting on the jib hoisting device 16 is equal to or less than the second predetermined value is the jib inertia coefficient (boom inertia coefficient K ) may be used.

(Concrete examples such as calculation by the calculation unit 73b)
As described above, the pressure of hydraulic cylinder 35 shown in FIG. 2 is controlled based on the state of boom 13 . A storage unit 73a shown in FIG. 5 stores information necessary for this control, and a calculation unit 73b calculates information necessary for this control.

[Example 1] The calculation unit 73b may determine the required pressure of the hydraulic cylinder 35 (see FIG. 2) based on the state of the boom 13 (see FIG. 2). In this case, the storage unit 73a may store relationships between various states of the boom 13 and required pressures. The storage unit 73a may also store the relationship between various states of the boom 13 and information necessary for the calculation unit 73b to calculate the required pressure. Then, the calculation unit 73b may determine (read or calculate) the required pressure of the hydraulic cylinder 35 according to the current state of the boom 13 .

[Example 1a] The calculation unit 73b sends the determined required pressure of the hydraulic cylinder 35 (see FIG. 2) or a pressure calculated based on the required pressure to the cylinder pressure control unit 60 (more specifically, the set pressure change valve 63). It may be set pressure to command. [Example 1b] Based on the required pressure of the hydraulic cylinder 35, the calculation unit 73b may determine the content of the command to the selection valve 263 (see FIG. 6), which will be described later.

[Example 2] The calculation unit 73b may determine the content of the command to the cylinder pressure control unit 60 based on the state of the boom 13 (see FIG. 2) without calculating the required pressure. [Example 2a] The storage unit 73a may store the relationship between various states of the boom 13 (see FIG. 2) and the content of the command to the cylinder pressure control unit 60 (specifically, the set pressure). . The calculation unit 73b may read and determine the content of the command to the cylinder pressure control unit 60 from the storage unit 73a according to the current state of the boom 13 (see FIG. 2). [Example 2b] The storage unit 73a may store the relationship between various states of the boom 13 (see FIG. 2) and contents of commands to the cylinder pressure control unit 260 (see FIG. 6). The calculation unit 73b may read and determine the content of the command to the cylinder pressure control unit 260 (see FIG. 6) from the storage unit 73a according to the current state of the boom 13 (see FIG. 2).

(When crane 1 is stopped)
When the crane 1 shown in FIG. 1 is stopped (including, for example, when the engine is stopped), the cylinder pressure control on/off valve 56 shown in FIG. 4 is set to the control OFF position 56a. At this time, the pressure of the hydraulic cylinder 35 is set to the set pressure of the relief valve 57 when the crane is stopped. At this time, the thrust of the hydraulic cylinder 35 suppresses the tilting of the boom 13 toward the reverse side D2 shown in FIG.

(examination)
In the tilt suppressing member 30 of the present embodiment, the thrust of the hydraulic cylinder 35 acts on the boom 13 via the connecting member 37 to apply the force of the lofting side D1. On the other hand, a case in which a winch (not shown) winds up the connection member 37 to apply a force on the lowering side D1 to the boom 13 will be considered. In this case, it is assumed that the connecting member 37 is hung between a plurality of sheaves provided on the upper rotating body 12 side and the boom 13 side. In this case, the configuration of the winch, sheave, and connecting member 37 may become complicated. On the other hand, the tilting suppressing member 30 of the present embodiment can have a simple configuration.

(Effect of the first invention)
The effects of the tilt suppressing device 20 shown in FIG. 2 are as follows. The fanning suppression device 20 includes a hydraulic cylinder 35, a state monitoring section 71 (see FIG. 5), and a cylinder pressure control section 60 (see FIG. 5). The hydraulic cylinder 35 applies a force to the boom 13 in a direction (lowering side D1) to rotate the boom 13 (raising member) to the front side X1.

[Configuration 1] The state monitoring unit 71 (see FIG. 5) monitors the state of the boom 13 including the structural length and the hoisting angle (boom hoisting angle θ). The cylinder pressure control section 60 (see FIG. 5) controls the pressure of the hydraulic cylinder 35 based on the state of the boom 13 monitored by the state monitoring section 71 (see FIG. 5).

[Configuration 1] provides the following effects. Depending on the structural length of the boom 13, the pressure of the hydraulic cylinder 35 required to suppress the tilting of the boom 13 toward the rear side X2 (reversal side D2) changes. Therefore, in [Configuration 1], the pressure of the hydraulic cylinder 35 is controlled based on the state of the boom 13 including the structural length of the boom 13 and the hoisting angle of the boom 13 (boom hoisting angle θ). Therefore, compared to the case where the control of the pressure of the hydraulic cylinder 35 is not performed based on the information of the boom 13 including the structural length of the boom 13 and the boom hoisting angle θ (for example, based only on the boom hoisting angle θ), the hydraulic pressure The pressure in cylinder 35 can be properly controlled. Therefore, the pressure of the hydraulic cylinder 35 for suppressing the tilting of the boom 13 can be controlled to an appropriate magnitude corresponding to the state of the boom 13 .

(Effect of the second invention)
[Configuration 2] The tilting suppressing device 20 includes a computing section 73b (see FIG. 5). The calculation unit 73b determines the required pressure of the hydraulic cylinder 35 based on the state of the boom 13 monitored by the state monitoring unit 71 (see FIG. 5). The cylinder pressure control section 60 controls the pressure of the hydraulic cylinder 35 based on the required pressure determined by the calculation section 73b.

[Configuration 2] allows the pressure of the hydraulic cylinder 35 to be controlled based on the required pressure of the hydraulic cylinder 35 based on the state of the boom 13 . Therefore, the pressure of the hydraulic cylinder 35 can be controlled more appropriately than when the pressure of the hydraulic cylinder 35 is controlled without being based on the required pressure of the hydraulic cylinder 35 (for example, in [Example 2] above).

(Effect of the third invention)
[Configuration 3] The state monitoring unit 71 (see FIG. 5) monitors the load acting on the boom hoisting device 14 (see FIG. 1) (hoisting device). As shown in FIG. 1, the boom hoisting device 14 applies a force to the boom 13 to rotate the boom 13 to the rear side X2 (reversal side D2). The calculation unit 73b (see FIG. 5) calculates the required pressure of the hydraulic cylinder 35 so that the load acting on the boom hoisting device 14 is equal to or less than a predetermined value.

[Configuration 3] provides the following effects. The larger the pressure of the hydraulic cylinder 35, the more the boom 13 can be restrained from being tilted toward the rear side X2. On the other hand, if the pressure of the hydraulic cylinder 35 is too large, the load acting on the boom hoisting device 14 may become excessive. In [Configuration 3] above, the required pressure of the hydraulic cylinder 35 (see [Configuration 2] above) is calculated so that the load acting on the boom hoisting device 14 is equal to or less than a predetermined value. Therefore, the pressure of the hydraulic cylinder 35 is suppressed from becoming excessive, and the load acting on the boom hoisting device 14 can be suppressed. As a result, the pressure of the hydraulic cylinder 35 can be controlled with higher accuracy.

(Effect of the fourth invention)
[Configuration 4] As shown in FIG. 4, the cylinder pressure control section 60 is configured to be able to continuously change the pressure of the hydraulic cylinder 35 .

According to [Configuration 4] above, the pressure of the hydraulic cylinder 35 can be controlled with high precision compared to the case where the cylinder pressure control unit 60 can only control the pressure of the hydraulic cylinder 35 in stages (see FIG. 6). .

(Effect of the sixth invention)
[Configuration 6-1] As shown in FIG. The lower member 31 is attached to the front side X1 portion of the upper revolving body 12 so as to be rotatable in the vertical direction Z. As shown in FIG. The upper revolving body 12 supports the boom 13 so that it can rise and fall. The upper member 32 is positioned at the front side X1 portion of the upper revolving body 12 and above the mounting portion of the lower member 31 to the upper revolving body 12 (for example, the Z1 portion above the base end portion 31f of the lower member). It is rotatably mounted in direction Z. The upper member 32 (for example, the upper and lower member connecting portion 32t) is rotatably connected to a portion of the lower member 31 that is different from the attachment portion (for example, the lower member base end portion 31f) to the upper revolving body 12 . The connection member 37 is connected to the lower member 31 and the upper member 32 at a position on the front side X1 from the boom support shaft 13f (the support shaft of the boom 13 to the upper swing body 12). A connecting member 37 is connected to the boom 13 .

[Configuration 6-2] The hydraulic cylinder 35 is included in the upper member 32 . The upper member 32 is provided so as to extend in the direction of expansion and contraction of the hydraulic cylinder 35 .

In the above [configuration 6-1], the connecting member 37 is connected to the lower member 31 and the upper member 32 at a position on the front side X1 of the boom support shaft 13f. Thus, tension members (ropes, foldable links, etc.) can be used as connecting members 37 (detailed above). Therefore, for example, compared to the case where the connection member 37 is a rod-shaped structure, it is possible to configure the members (for example, the lower member 31, the upper member 32, and the connection member 37) that constitute the tilt suppression device 20 more compactly. can.

[Configuration 6-2] allows the upper member 32 to reliably support the force transmitted from the hydraulic cylinder 35 to the upper member 32 . As a result, the thrust of the hydraulic cylinder 35 can be efficiently transmitted to the boom 13 .

(Effect of the seventh invention)
[Arrangement 7] The hydraulic cylinder 35 is set to be fully retracted when the boom hoisting angle θ (the boom hoisting angle of the boom 13) is the maximum allowable hoisting angle (for example, the maximum angle Amax).

[Configuration 7] allows the hydraulic cylinder 35 to function as a rod (holding rod). Therefore, it is possible to reliably (mechanically) suppress the boom 13 from being swayed toward the rear side X2 when the boom hoisting angle θ is the maximum allowable hoisting angle.

(Effect of the eighth invention)
[Arrangement 8] The cylinder pressure control section 60 (see FIG. 5) controls the hydraulic cylinder 35 when the boom hoisting angle θ is within a predetermined range A. As shown in FIG. 3, the hydraulic cylinder 35 is set to be in an extended state when the boom hoisting angle .theta.

The following effect is obtained by the above [Configuration 8]. In the above [Configuration 6], the hydraulic cylinder 35 expands and contracts with the ups and downs of the boom 13, and the tilting suppression device 20 is configured so that the hydraulic cylinder 35 contracts as the boom 13 rotates to the rear side X2 (reversal side D2). restraining member 30) may be configured. Further, in the above [Configuration 8], the cylinder pressure control section 60 (see FIG. 5) controls the hydraulic cylinder 35 when the boom hoisting angle θ is within the predetermined range A. Therefore, when the boom hoisting angle θ is smaller than the minimum angle Amin, there is no need to control the hydraulic cylinder 35 and the hydraulic cylinder 35 does not need to extend or contract. Therefore, in the above [configuration 8], the hydraulic cylinder 35 is set to be in an extended state (for example, a fully extended state or a substantially fully extended state) when the boom hoisting angle θ is the minimum angle Amin within the predetermined range A. . Therefore, it is possible to prevent the stroke (extendable length) of the hydraulic cylinder 35 from exceeding a required length, and the size of the hydraulic cylinder 35 can be reduced.

(Second embodiment)
With reference to FIG. 6, the difference from the first embodiment will be described with respect to the tilt suppression device 220 of the crane 1 (see FIG. 1) of the second embodiment. Note that, of the tilt suppressing device 220, the description of the points in common with the tilt suppressing device 20 of the first embodiment (see FIG. 4, etc.) will be omitted. The main difference is the configuration of the cylinder pressure control section 260 .

In the example shown in FIG. 4 , the cylinder pressure control section 60 is configured to be able to continuously change the pressure of the hydraulic cylinder 35 . On the other hand, in the present embodiment, as shown in FIG. 6, the cylinder pressure control section 260 is configured to be able to change the pressure of the hydraulic cylinder 35 stepwise (multiple steps). Specifically, the cylinder pressure control section 260 includes a plurality of pressure setting relief valves 261 and a selection valve 263 .

The pressure setting relief valve 261 is a relief valve that can set the maximum pressure of the hydraulic cylinder 35 (for the relief valve, see the description of the crane stop relief valve 57 and the like). A case where the cylinder pressure control unit 260 can change the pressure of the hydraulic cylinder 35 in two steps will be mainly described here. The pressure setting relief valve 261 includes a high pressure relief valve 261a and a low pressure relief valve 261b.

The high pressure relief valve 261a is a relief valve that can set the maximum pressure of the hydraulic cylinder 35 to a high set pressure. The magnitude of the high set pressure is set, for example, so that the hydraulic cylinder 35 can output a thrust greater than or equal to the thrust required to suppress the swinging of the boom 13 toward the reverse side D2 shown in FIG.

The low-pressure relief valve 261b, as shown in FIG. 6, is a relief valve that can set the maximum pressure of the hydraulic cylinder 35 to a low-pressure set pressure that is lower than the high-pressure set pressure.

The selection valve 263 connects one of the plurality of pressure setting relief valves 261 (eg, the high pressure relief valve 261a and the low pressure relief valve 261b) to the hydraulic cylinder 35 (more specifically, the bottom chamber 35a1). For example, select valve 263 includes a high pressure select position 263a and a low pressure select position 263b. The high pressure selection position 263a is selected when the pressure (more specifically, the maximum pressure) of the hydraulic cylinder 35 is set to the high pressure set pressure. The low pressure selection position 263b is selected when the pressure (more specifically, the maximum pressure) of the hydraulic cylinder 35 is set to the low pressure set pressure. When three or more pressure setting relief valves 261 are provided, the selection valve 263 is configured to select one from the three or more pressure setting relief valves 261 .

(activation)
[Details of Example 1b] For example, the computing unit 73b (see FIG. 5) determines the required pressure based on the state of the boom 13 (see FIG. 2) monitored by the state monitoring unit 71 (see FIG. 5), The required pressure may determine which of the plurality of pressure setting relief valves 261 to select. Specifically, for example, a reference value for determining which of the plurality of pressure setting relief valves 261 to select is set in the calculation unit 73b (see FIG. 5). Based on the comparison between the required pressure and the reference value, the calculation unit 73b then determines which of the pressure setting relief valves 261 to select. The calculation unit 73b causes the output unit 73c to output a command to select the determined pressure setting relief valve 261 to the selection valve 263 .

More specifically, a reference value for determining whether to select the high-pressure relief valve 261a or the low-pressure relief valve 261b is set in the calculation unit 73b (see FIG. 5). This reference value may be, for example, the low pressure set pressure (the set pressure of the low pressure relief valve 261b) or a value equal to or lower than the low pressure set pressure. Then, the calculation unit 73b (see FIG. 5) determines to select the low pressure relief valve 261b when the required pressure is equal to or lower than the reference value. In this case, the calculation unit 73b (see FIG. 5) causes the output unit 73c (see FIG. 5) to output to the selection valve 263 a command to select the low pressure selection position 263b. Further, the calculation unit 73b determines to select the high pressure relief valve 261a when the required pressure is greater than the reference value. In this case, the calculation unit 73b (see FIG. 5) causes the output unit 73c (see FIG. 5) to output to the selection valve 263 a command to select the high pressure selection position 263a.

[Details of Example 2b] For example, the calculation unit 73b (see FIG. 5) determines the required pressure based on the state of the boom 13 (see FIG. 2) monitored by the state monitoring unit 71 (see FIG. 5). It may be determined which of the plurality of pressure setting relief valves 261 to select. Specifically, for example, the computing unit 73b (see FIG. 5) selects the plurality of pressure setting relief valves 261 based only on the combination of the structural length of the boom 13 (see FIG. 2) and the boom hoisting angle θ (see FIG. 2). may decide which valve to select. For example, the computing unit 73b (see FIG. 5) selects the high pressure relief valve 261a or the low pressure relief valve 261a based only on the combination of the structural length of the boom 13 (see FIG. 2) and the boom hoisting angle θ (see FIG. 2). It may be determined whether to select valve 261b.

(Effect of the fifth invention)
[Configuration 5] As shown in FIG. 6 , the cylinder pressure control section 260 includes a plurality of pressure setting relief valves 261 and a selection valve 263 . A plurality of pressure setting relief valves 261 set the maximum pressure of the hydraulic cylinder 35 in a plurality of stages. The selection valve 263 connects one of the plurality of pressure setting relief valves 261 to the hydraulic cylinder 35 based on the state of the boom 13 (see FIG. 2) monitored by the state monitoring section 71 (see FIG. 5).

[Configuration 5] makes it possible to configure the cylinder pressure control section 260 (hydraulic circuit) more simply than in the case where the pressure of the hydraulic cylinder 35 can be changed continuously (see FIG. 4). . Moreover, the control of the pressure of the hydraulic cylinder 35 can be simpler than when the pressure of the hydraulic cylinder 35 can be changed continuously.

(Modification)
The above embodiments may be modified in various ways. For example, components from different embodiments may be combined. For example, the configuration (for example, arrangement, shape, etc.) of each component may be changed. For example, connections between components shown in FIGS. 4 to 6, etc. may be changed. For example, the value (for example, the above-mentioned “predetermined value”) or range (for example, predetermined range A (see FIG. 2), etc.) may be constant, may be changed by manual operation, or may be changed automatically according to some conditions. may be For example, the number of components may vary and some components may not be provided. For example, fixing, coupling, etc. between components may be direct or indirect. For example, what has been described as a plurality of different members or parts may be treated as one member or part. For example, what has been described as one member or portion may be divided into a plurality of different members or portions.

For example, when the tilt suppression device 20 shown in FIG.

12 upper rotating body 13 boom (raising member)
14 boom hoisting device (hoisting device)
15 Jib (raising member)
16 Jib hoisting device (hoisting device)
20, 220 fanning suppression device 31 lower member 32 upper member 35 hydraulic cylinder 37 connection member 60, 260 cylinder pressure control unit 71 condition monitoring unit 73b calculation unit 261 pressure setting relief valve 263 selection valve A predetermined range Amin minimum angle X1 front side θ boom Luffing angle (Luffing angle of the luffing member)

Claims (8)

a hydraulic cylinder that applies a force to the hoisting member in a direction to rotate the hoisting member forward;
a condition monitoring unit for monitoring the condition of the hoisting member, including configuration length and hoisting angle;
a cylinder pressure control section that controls the pressure of the hydraulic cylinder based on the state of the hoisting member monitored by the state monitoring section;
comprising
Agitation suppression device. The fanning suppression device according to claim 1,
a computing unit that determines the required pressure of the hydraulic cylinder based on the state of the hoisting member monitored by the state monitoring unit;
The cylinder pressure control unit controls the pressure of the hydraulic cylinder based on the required pressure determined by the calculation unit.
Agitation suppression device. The fanning suppression device according to claim 2,
The state monitoring unit monitors the load acting on the hoisting device that applies a force to the hoisting member to rotate the hoisting member rearward,
The calculation unit calculates the required pressure of the hydraulic cylinder so that the load acting on the hoisting device is equal to or less than a predetermined value.
Agitation suppression device. The fanning suppression device according to any one of claims 1 to 3,
The cylinder pressure control unit is configured to be able to continuously change the pressure of the hydraulic cylinder,
Agitation suppression device. The fanning suppression device according to any one of claims 1 to 3,
The cylinder pressure control unit is
a plurality of pressure setting relief valves for setting the maximum pressure of the hydraulic cylinder in a plurality of stages;
a selection valve that connects one of the plurality of pressure setting relief valves to the hydraulic cylinder based on the state of the hoisting member monitored by the state monitoring unit;
comprising
Agitation suppression device. The fanning suppression device according to any one of claims 1 to 5,
a lower member vertically rotatably attached to a front portion of the upper revolving body that hoistably supports the hoisting member;
It is mounted rotatably in the vertical direction on the front part of the upper revolving body and above the mounting part of the lower member to the upper revolving body, and the mounting part of the lower member to the upper revolving body. is a top member rotatably connected to different parts;
a connection member connected to the lower member and the upper member at a position forward of the support shaft of the hoisting member to the upper revolving body and connected to the hoisting member;
with
the hydraulic cylinder is included in the upper member;
The upper member is provided so as to extend in the expansion and contraction direction of the hydraulic cylinder,
Agitation suppression device. The fanning suppression device according to claim 6,
The hydraulic cylinder is set to be in a fully retracted state when the hoisting angle of the hoisting member is the maximum allowable hoisting angle.
Agitation suppression device. The fanning suppression device according to claim 6 or 7,
The cylinder pressure control unit controls the pressure of the hydraulic cylinder when the hoisting angle of the hoisting member is within a predetermined range,
The hydraulic cylinder is set to be in an extended state when the hoisting angle of the hoisting member is the minimum angle within the predetermined range.
Agitation suppression device.

Images