Operating machinery

Abstract

The present invention relates to a working machine capable of improving the working efficiency of split operations of a telescopic arm. The working machine is provided with a telescopic arm capable of being extended and retracted by moving a plurality of arm parts in sequence. The working machine comprises: a connecting pin that connects adjacent arm parts to each other or releases the connection between adjacent arm parts; and a pin moving part that moves the connecting pin by the power of any one of a first power and a second power, thereby releasing the engagement between adjacent arm parts.

Description

Technical Field

[0001] The present invention relates to a working machine including a telescopic arm. The telescopic arm includes, for example, a plurality of arm members and can perform a telescopic operation by changing the positions of mutually adjacent arm members. Background Art

[0002] As a conventional working machine, there is known a crane device having a telescopic arm including a plurality of arm members and capable of performing a telescopic operation by changing the positions of adjacent arm members (for example, Patent Document 1).

[0003] The crane device includes an arm connection pin that connects adjacent arm members to each other, and a pin drive mechanism that switches between connection and disconnection of the arm members by the arm connection pin.

[0004] When a crane device is moved between a storage location and a work location using a general road or when performing maintenance, it is sometimes necessary to separate the telescopic boom.

[0005] In a crane device, for example, when a telescopic boom is separated into two parts, an operator manually drives a pin driving mechanism to move an arm connection pin to release the connection between adjacent arm parts, thereby separating the telescopic boom into two parts.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Publication No. 2019-142620 Summary of the invention

[0009] Problem that the invention aims to solve

[0010] In the above-mentioned working machine, a structure capable of efficiently performing the split operation of the telescopic arm is required.

[0011] An object of the present invention is to provide a working machine capable of improving the working efficiency of a split working of a telescopic arm.

[0012] Solutions to the problem

[0013] One aspect of the working machine of the present invention is a working machine including a telescopic arm that can be extended and retracted by sequentially moving a plurality of arm members.

[0014] The operating machinery includes:

[0015] a connecting pin that connects adjacent arm members to each other or disconnects adjacent arm members from each other; and

[0016] The pin moving portion moves the connecting pin by using either the first power or the second power, thereby releasing the engagement between the adjacent arm members.

[0017] Effects of the Invention

[0018] According to the present invention, it is possible to provide a working machine capable of improving the working efficiency of the split working of the telescopic arm. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a side view of a mobile crane showing one embodiment of the present invention.

[0020] Figure 2 is a side view of the telescopic arm.

[0021] Figure 3 yes Figure 2 AA cross-section diagram.

[0022] Figure 4 yes Figure 3 Magnified view of section X.

[0023] Figure 5 It is a three-dimensional diagram of the arm connection mechanism.

[0024] Figure 6 yes Figure 5 A1 view.

[0025] Description of Reference Numerals

[0026] 1 Mobile crane

[0027] 10 Body

[0028] 11. Wheel

[0029] 12 Outriggers

[0030] 20 Crane device

[0031] 21 Telescopic arm

[0032] 21a Basic arm (arm part)

[0033] 21b Second arm section (arm part)

[0034] 21c Third arm (arm part)

[0035] 21d Fourth arm (arm part)

[0036] 21e Fifth arm (arm part)

[0037] 21f Top arm (arm part)

[0038] 211a, 211b fixed part

[0039] 212c, 212d lateral side plate

[0040] 213d Upper side panel

[0041] 22 Cab

[0042] 23 Heaving Cylinder

[0043] 30 Arm telescopic mechanism

[0044] 31 Telescopic Cylinder

[0045] 31a Cylinder

[0046] 31b Piston rod

[0047] 32 Cylinder-arm connection mechanism

[0048] 32a Cylinder pin

[0049] 32b concave part

[0050] 32c Cylinder-arm connection switching actuator

[0051] 33 Arm connection mechanism

[0052] 33a1, 33a2 Arm connecting pin

[0053] 33b Pin drive mechanism

[0054] 33b1 Operation Department

[0055] 33c1, 33c2 Pin engagement holes

[0056] 33d Opening

[0057] 37 Support

[0058] 371 base

[0059] 372a, 372b Installation part

[0060] 373 Support

[0061] 374 Through Holes

[0062] 34a, 34b Pin moving part

[0063] 342a, 342b Support shaft

[0064] 343a, 343b sleeve

[0065] 344a, 344b Force spring

[0066] 345a, 345b connection part

[0067] 35a, 35b First transmission part

[0068] 36 Second Transmission Unit

[0069] 361 Operating shaft

[0070] 361a Shaft side gear

[0071] 361b bearing

[0072] 362 Transmission shaft

[0073] 362a Supported portion

[0074] 362b First external thread portion

[0075] 362c Second external thread portion

[0076] 363 Gear

[0077] 363a key

[0078] 364 First Nut

[0079] 364a Internal thread

[0080] 365 Second Nut

[0081] 365a Internal thread

[0082] 40 Rotating Platform

[0083] 41 Actuator

[0084] 50 Space DETAILED DESCRIPTION

[0085] Figures 1 to 6 It is a figure which shows one embodiment of the present invention.

[0086] like Figure 1 As shown, a mobile crane 1 equipped with a crane device of the present invention includes a vehicle body 10 for traveling on a general road or a work area and a crane device 20 for performing a lifting operation. The crane device 20 is equivalent to an example of a work machine. It should be noted that the work machine is not limited to the crane device. The work machine may be, for example, a lifting device mounted on an aerial work vehicle. That is, the work machine may be various work machines equipped with a retractable telescopic arm.

[0087] The vehicle body 10 includes wheels 11 and is driven by an engine as a power source. In addition, outriggers 12 are provided on the left and right sides of the front and rear sides of the vehicle body 10, and the outriggers 12 are used to lift the vehicle body 10 and support it during lifting operations.

[0088] The crane device 20 includes a telescopic arm 21 which is freely retractable and provided on the vehicle body 10 in a manner that allows it to rise and fall, and a cab 22 for operating the lifting operation of the crane device 20. The telescopic arm 21 and the cab 22 are supported by a revolving platform 40 which is rotatable in the horizontal direction relative to the vehicle body 10. The crane device 20 is arranged on one side of the revolving platform 40 in the width direction, and the cab 22 is arranged on the other side of the revolving platform 40 in the width direction.

[0089] The telescopic arm 21 includes a plurality of arm parts 21a, 21b, 21c, 21d, 21e, and 21f (hereinafter, described as "arm parts 21a to 21f"). The telescopic arm 21 is a telescopic arm of a telescopic type that can be inserted into and out of the arm parts 21a to 21e so that the arm parts 21b to 21f adjacent to the front end side can be freely accommodated therein. The telescopic arm 21 of this embodiment is a six-stage arm consisting of a basic arm 21a, a second arm 21b, a third arm 21c, a fourth arm 21d, a fifth arm 21e, and a top arm 21f in the following order from the base end side.

[0090] The base end of the base arm 21a is swingably connected to the revolving platform 40. A hydraulic up-and-down cylinder 23 is connected between the base arm 21a and the revolving platform 40. The telescopic arm 21 performs an up-and-down motion by the telescopic motion of the up-and-down cylinder.

[0091] The telescopic arm 21 is telescopically operated by the arm telescopic mechanism 30 .

[0092] like Figure 2 to Figure 4 As shown, the arm telescopic mechanism 30 includes: a telescopic cylinder 31 for moving arm parts 21b~21f other than the basic arm 21a; a cylinder-arm connecting mechanism 32 for detachably connecting the arm parts 21b~21f other than the basic arm 21a to the telescopic cylinder 31; and an arm connecting mechanism 33 for detachably connecting the arm parts 21a~21e and the arm parts 21b~21f adjacent to the front end side thereof.

[0093] like Figure 2 As shown in FIG. 1 , the telescopic cylinder 31 includes a cylinder tube 31a and a piston rod 31b, and performs telescopic operation using hydraulic oil discharged from a hydraulic pump. The end of the piston rod 31b side of the telescopic cylinder 31 is connected to the base end of the basic arm 21a in the basic arm 21a, and the cylinder tube 31a moves relative to the piston rod 31b. In this embodiment, the piston rod 31b is equivalent to an example of a fixed part of the telescopic cylinder 31. The cylinder tube 31a is equivalent to an example of a movable part of the telescopic cylinder 31.

[0094] like Figure 3As shown, the cylinder-arm connection mechanism 32 includes a cylinder pin 32a and a cylinder-arm connection switching actuator 32c. The cylinder pin 32a is provided on the outer periphery of the cylinder barrel 31a of the telescopic cylinder 31. The cylinder pin 32a can engage with arm components 21b to 21f other than the basic arm 21a. The arm components 21b to 21f are arm components that are movable in the axial direction of the telescopic arm 21 during the telescopic action of the telescopic arm 21. The cylinder-arm connection switching actuator 32c is, for example, a hydraulic cylinder, which is provided on the cylinder barrel 31a of the telescopic cylinder 31. The cylinder-arm connection switching actuator 32c installs or removes a pair of cylinder pins 32a with respect to the recessed portion 32b of the arm components 21b to 21f other than the basic arm 21a.

[0095] The arm connection mechanism 33 includes: a pair of arm connection pins 33a1, 33a2; pin engagement holes 33c1, 33c2; and a pin driving mechanism 33b. Figure 3 As shown, a pair of arm connection pins 33a1 and 33a2 are provided on the base end side of each of the arm members 21b to 21f except the basic arm 21a.

[0096] The arm connection pins 33a1 and 33a2 respectively connect the arm parts 21a to 21f that are adjacent to each other. The pin drive mechanism 33b switches between connection and disconnection between the arm parts 21a to 21f by moving the pair of arm connection pins 33a1 and 33a2 in the width direction of the arm parts 21a to 21f (hereinafter referred to as the "width direction of the telescopic arm 21").

[0097] The pin engagement holes 33c1 and 33c2 are provided in the arm members 21a to 21e located on the base end side (ie, the arm members excluding the distal arm 21f), and can be fitted with the pair of arm connection pins 33a1 and 33a2.

[0098] like Figure 2 As shown, the pin engaging holes 33c1 and 33c2 are provided at a plurality of positions on each of the arm members 21a to 21e. The pin engaging holes 33c1 and 33c2 are provided not only at the base end side and the front end side of the arm members 21a to 21e, but also at positions on the arm members 21a to 21e where the arm members 21b to 21f at the front end side of the arm members 21a to 21e at the base end side reach a predetermined extension length.

[0099] It should be noted that the outer direction in the width direction of the telescopic arm 21 refers to the direction from the central axis in the axial direction of the telescopic arm 21 toward the outer surface in the width direction of the telescopic arm 21. On the other hand, the inner direction in the width direction of the telescopic arm 21 refers to the direction from the outer surface in the width direction of the telescopic arm 21 toward the central axis in the axial direction of the telescopic arm 21.

[0100] A pair of arm connecting pins 33a1, 33a2 are respectively composed of components with a roughly cylindrical shape. The arm connecting pins 33a1, 33a2 have a pair of flat surfaces (not shown) on the outer peripheral surfaces of their respective front end portions. The pair of flat surfaces are opposite to each other in the radial direction of the arm connecting pins 33a1, 33a2. The above-mentioned flat surfaces are provided to reduce the average contact pressure on the abutment portions of the arm connecting pins 33a1, 33a2 abutting against the pin engaging holes 33c1, 33c2. The pair of arm connecting pins 33a1, 33a2 are arranged on both sides of the width direction of the arm parts 21b~21f in a posture in which the central axis of the cylindrical shape is oriented toward the width direction of the arm parts 21b~21f and in a manner that allows them to move freely in the width direction of the arm parts 21b~21f.

[0101] The pin drive mechanism 33b is arranged at a position between a pair of arm connecting pins 33a1 and 33a2 on the inner side of the arm parts 21b to 21f. The pin drive mechanism 33b has a mechanism such as a ball screw or a lead screw that converts rotational motion into linear motion. The pin drive mechanism 33b is actuated by an actuator 41 that is electrically driven or hydraulically driven, so that the pair of arm connecting pins 33a1 and 33a2 are moved in the width direction of the arm parts 21b to 21f respectively. In the present embodiment, the actuator 41 is arranged on the cylinder 31a which is the movable part of the telescopic cylinder 31. Thus, the actuator 41 moves in the axial direction of the telescopic arm 21 together with the cylinder 31a.

[0102] Below, refer to Figure 3 to Figure 6 The specific structure of the pin drive mechanism 33b is described. In addition, the pin drive mechanism 33b provided in the arm member 21d (fourth section arm 21d) is described below. In terms of the relationship with the arm member 21c, the arm member 21d is equivalent to an example of an inner arm member. In terms of the relationship with the arm member 21d, the arm member 21c (third section arm) provided on the outer side and the base end side of the arm member 21d and adjacent to the arm member 21d is equivalent to an example of an outer arm member. The structure of the pin drive mechanism 33b of the arm members 21b, 21c, 21e, and 21f is the same as the pin drive mechanism 33b of the arm member 21d. Therefore, the following description of the pin drive mechanism 33b of the arm member 21d can be appropriately applied to the structure of the pin drive mechanism 33b of the arm members 21b, 21c, 21e, and 21f.

[0103] The pin drive mechanism 33b includes: a support member 37; a pair of pin moving parts 34a, 34b; first transmission parts 35a, 35b; and a second transmission part 36. In the telescopic operation of the telescopic arm 21, when the connection between the inner arm member, i.e., the arm member 21d, and the outer arm member, i.e., the arm member 21c, is released, the pair of pin moving parts 34a, 34b are respectively actuated by the power of the actuator 41, so that the arm connecting pins 33a1, 33a2 of the arm member 21d are moved inward in the width direction of the telescopic arm 21. As a result, the engagement between the arm connecting pins 33a1, 33a2 and the pin engaging holes 33c1, 33c2 of the arm member 21c is released. The power of the actuator 41 is equivalent to an example of the first power.

[0104] Furthermore, in the telescopic operation of the telescopic arm 21, when the inner arm member, i.e., the arm member 21d, is connected to the outer arm member, i.e., the arm member 21c, when the power is no longer applied from the actuator 41, the pin driving mechanism 33b moves the arm connection pins 33a1, 33a2 of the arm member 21d toward the outer side in the width direction of the telescopic arm 21 by the elastic force (biasing force) applied from the biasing springs 344a, 344b described later. As a result, the arm connection pins 33a1, 33a2 of the arm member 21d are engaged with the pin engagement holes 33c1, 33c2 of the arm member 21c.

[0105] Furthermore, when the connection between the inner arm member, i.e., the arm member 21d, and the outer arm member, i.e., the arm member 21c, is manually released, the pin driving mechanism 33b uses the power input from the outside of the telescopic arm 21 by the action of the operator to move the arm connection pins 33a1 and 33a2 inward in the width direction of the telescopic arm 21. As a result, the engagement between the arm connection pins 33a1 and 33a2 and the pin engagement holes 33c1 and 33c2 of the arm member 21c is released. The power input from the outside of the telescopic arm 21 by the action of the operator is an example of the second power.

[0106] The support 37 is a member for supporting the pin moving parts 34a and 34b on the fixing parts 211a and 211b of the arm member 21d. The fixing parts 211a and 211b are provided on the inner surface of the arm member 21d. The fixing parts 211a and 211b are arranged opposite to each other in a state of being spaced apart in the width direction of the telescopic arm 21.

[0107] The support member 37 includes a base 371 and a pair of mounting portions 372a, 372b. The base 371 is a box-shaped member that is long in the width direction of the telescopic arm 21. The base 371 includes an end portion ( Figure 3 to Figure 6 The right end in the figure) that is, the first end and the other end in the width direction of the telescopic arm 21 ( Figure 3 to Figure 6The left end in the middle) is the second end. In such a base 371, a part of the second transmission part 36 described later is accommodated.

[0108] The mounting portion 372a is plate-shaped and provided at the first end portion of the base portion 371. The mounting portion 372a is fixed to the fixing portion 211a of the arm member 21d by a fixing member (fastening members such as bolts and nuts).

[0109] The mounting portion 372b is plate-shaped and provided at the second end portion of the base portion 371. The mounting portion 372b is fixed to the fixing portion 211b of the arm member 21d by a fixing member (fastening members such as bolts and nuts).

[0110] The pin moving parts 34a and 34b respectively include: support shafts 342a and 342b; sleeves 343a and 343b; biasing springs 344a and 344b; and connecting parts 345a and 345b.

[0111] The support shafts 342a and 342b are shaft members extending in the width direction of the telescopic arm 21. The support shafts 342a and 342b each include one side ( Figure 3 to Figure 6 The right side in the middle) is the first end and the other side in the axial direction ( Figure 3 to Figure 6 The end portion (on the left side in FIG. 1 ) is the second end portion.

[0112] The support shafts 342a and 342b are provided in parallel with each other and adjacent to each other in the axial direction of the telescopic arm 21. The ends of both sides of the support shafts 342a and 342b are supported by the mounting portions 372a and 372b of the support member 37.

[0113] The sleeves 343a and 343b are cylindrical and extend in the width direction of the telescopic arm 21. The sleeves 343a and 343b each include one side ( Figure 3 to Figure 6 The right side in the middle) end, that is, the first end and the other side in the width direction of the telescopic arm 21 ( Figure 3 to Figure 5 The end portion (on the left side in FIG. 1 ) is the second end portion.

[0114] The first end portion ( Figure 6 Therefore, the central axis of the sleeve 343a coincides with the central axis of the support shaft 342a. The sleeve 343a can move in the axial direction (the width direction of the telescopic arm 21) relative to the support shaft 342a.

[0115] In a state where the arm connection pin 33 a 1 is engaged with the pin engagement hole 33 c 1 , the first end surface of the sleeve 343 a , which is an end surface on the first end side, comes into contact with the mounting portion 372 a of the support member 37 .

[0116] In addition, the second end portion ( Figure 6 Therefore, the central axis of the sleeve 343b coincides with the central axis of the support shaft 342b. The sleeve 343b can move in the axial direction (the width direction of the telescopic arm 21) relative to the support shaft 342b.

[0117] When the arm connection pin 33 a 2 is engaged with the pin engagement hole 33 c 2 , the second end surface of the sleeve 343 b , which is an end surface on the second end side, comes into contact with the mounting portion 372 b of the support member 37 .

[0118] The biasing springs 344a and 344b are coil springs. The second end portion ( Figure 6 The biasing spring 344a is provided in a compressed state between the sleeve 343a and the mounting portion 372b of the support member 37. The biasing spring 344a always biases the sleeve 343a toward one side (outside) in the width direction of the telescopic arm 21.

[0119] The first end portion ( Figure 6 The biasing spring 344b is provided in a compressed state between the sleeve 343b and the mounting portion 372a of the support member 37. The biasing spring 344b always biases the sleeve 343b toward the other side (outside) in the width direction of the telescopic arm 21.

[0120] The connecting parts 345a and 345b connect the sleeves 343a and 343b to the arm connecting pins 33a1 and 33a2, respectively. Therefore, the arm connecting pins 33a1 and 33a2 can move together with the sleeves 343a and 343b, respectively.

[0121] The first transmission parts 35a and 35b receive the first power, namely the actuator 41 (see Figure 3 ) and transmits the power to the pin moving parts 34a, 34b.

[0122] The first transmission part 35a is fixed to the sleeve 343a. Therefore, the first transmission part 35a can move together with the sleeve 343a. In addition, the first transmission part 35a can be locked on the locking part provided on the actuator 41. Such a first transmission part 35a transmits the power input from the actuator 41 to the sleeve 343a.

[0123] The first transmission part 35b is fixed to the sleeve 343b. Therefore, the first transmission part 35b can move together with the sleeve 343b. In addition, the first transmission part 35b can be locked on a locking part (not shown) provided on the actuator 41. Such a first transmission part 35b transmits the power input from the actuator 41 to the sleeve 343b.

[0124] When the state changes from the state in which the arm connecting pins 33a1, 33a2 are engaged with the pin engaging holes 33c1, 33c2 (hereinafter referred to as the "arm connected state") to the state in which the engagement between the arm connecting pins 33a1, 33a2 and the pin engaging holes 33c1, 33c2 is released (hereinafter referred to as the "arm non-connected state"), the locking portion of the actuator 41 engages with the first transmission portion 35a, 35b.

[0125] Then, the first transmission parts 35a and 35b are moved from Figure 3 , Figure 5 and Figure 6 In the state shown, the telescopic arm 21 moves inwardly in the width direction. Then, the sleeves 343a and 343b move inwardly in the width direction of the telescopic arm 21 together with the first transmission parts 35a and 35b.

[0126] Since the sleeves 343a and 343b are connected to the arm connection pins 33a1 and 33a2 via the connection parts 345a and 345b, the arm connection pins 33a1 and 33a2 move together with the sleeves 343a and 343b toward the inner side in the width direction of the telescopic arm 21. As a result, the engagement between the arm connection pins 33a1 and 33a2 and the pin engagement holes 33c1 and 33c2 is released, so that the arm member 21c and the arm member 21d are in the arm non-connected state.

[0127] The second transmission unit 36 ​​receives the power (second power) input from the outside of the telescopic arm 21 by the operator's action, and transmits the power to the pin moving units 34a and 34b. In this embodiment, the power is generated by the operator using a tool T such as a wrench (see Figure 3 ) is input into the rotational force of the second transmission part 36.

[0128] The second power may be power input from the outside of the telescopic arm 21 by the operator's action, and is not limited to the form in the present embodiment. For example, the tool T may be an electric tool.

[0129] The structure of the second transmission part 36 of this embodiment is described below. The second transmission part 36 has an operation part 33b1 that is operated when the connection between the arm part 21c and the arm part 21d is released, at a position that can be accessed from the outside of the arm part 21d. The operation part 33b1 can be connected to the tool T and is provided near the outer surface of the arm part 21d.

[0130] The operation portion 33 b 1 is a portion where an operator manually inputs an operation for moving the pair of arm connection pins 33 a 1 and 33 a 2 in the width direction of the telescopic arm 21 by using a tool T such as a wrench.

[0131] Specifically, the second transmission unit 36 ​​includes an operation shaft 361 , a transmission shaft 362 , a gear 363 , a first nut 364 , and a second nut 365 .

[0132] The operating shaft 361 is a shaft member extending in the width direction of the telescopic arm 21. The operating shaft 361 includes a first end portion on one side (inner side) of the telescopic arm 21 in the width direction and a second end portion on the other side (outer side) of the telescopic arm 21 in the width direction.

[0133] The operating shaft 361 has a shaft-side gear 361a at a portion near the first end. The first end of the operating shaft 361 is rotatably supported by the mounting portion 372b of the support member 37. The second end of the operating shaft 361 is rotatably supported by the lateral side plate portion 212d of the arm member 21d via a bearing 361b.

[0134] In this embodiment, the second end of the operating shaft 361 is supported by the lateral side plate portion 212d. However, the second end of the operating shaft 361 may be supported by a side plate portion other than the lateral side plate portion 212d.

[0135] For example, the second end of the operating shaft may be supported by the upper plate portion 213d of the arm member 21d. In this case, the operating shaft may be an axis member extending in the vertical direction of the arm member 21d. The vertical direction of the arm member 21d refers to the vertical direction of the arm member 21d when the telescopic arm 21 is in the fully collapsed state ( Figure 1 The up and down direction (sky-earth direction) when the state is shown).

[0136] The end surface of the second end side of the operating shaft 361 (hereinafter referred to as the "operated surface") is located outside the outer side surface of the lateral plate portion 212d. In other words, the operated surface exists in the space 50 between the outer side surface of the lateral plate portion 212d and the inner side surface of the lateral plate portion 212c of the arm member 21c.

[0137] The aforementioned operating portion 33b1 is provided on the operated surface of the operating shaft 361. The operating portion 33b1 is in the shape of a hexagonal prism that fits into a recess provided at the front end of the tool T used by the operator. The operating portion 33b1 can be operated via an opening 33d provided on the arm member 21c adjacent to the base end side of the arm member 21d and on the outside in the width direction of the telescopic arm 21. The operating portion 33b1 is located at a position closer to the outside, for example, about 40 mm from the outer side of the arm member 21d.

[0138] The transmission shaft 362 is a shaft member extending in the width direction of the telescopic arm 21. The transmission shaft 362 includes one side in the axial direction ( Figure 3 , Figure 4 and Figure 6 The right side in the middle) is the first end and the other side in the axial direction ( Figure 3, Figure 4 and Figure 6 The end portion (on the left side in FIG. 1 ) is the second end portion.

[0139] The transmission shaft 362 has a supported portion 362 a at the center portion in the axial direction (the width direction of the telescopic arm 21 ). The outer diameter of the supported portion 362 a is larger than the outer diameter of other portions of the transmission shaft 362 .

[0140] Such supported portion 362a is supported by a support portion 373 provided on a base portion 371 of the support member 37 in a state where it can rotate but is prevented from moving in the axial direction (width direction of the telescopic arm 21). That is, the transmission shaft 362 can rotate but cannot move in the axial direction.

[0141] The transmission shaft 362 has a first external thread portion 362b on the outer circumference between the first end and the supported portion 362a. The transmission shaft 362 has a second external thread portion 362c on the outer circumference between the second end and the supported portion 362a. In addition, the second external thread portion 362c is not provided at the second end of the transmission shaft 362.

[0142] The first external thread portion 362b is threadedly engaged with an internal thread portion 364a of a first nut 364 described below. The second external thread portion 362c is threadedly engaged with an internal thread portion 365a of a second nut 365 described below.

[0143] The portion of the transmission shaft 362 near the second end is inserted into the through hole 374 of the mounting portion 372b of the support member 37. The second end of the transmission shaft 362 protrudes to a position further outward in the width direction of the telescopic arm 21 than the mounting portion 372b.

[0144] The gear 363 is a cylindrical component and has a tooth portion on the outer circumferential surface. The tooth portion is composed of a plurality of teeth arranged at intervals in the circumferential direction. The second end of the transmission shaft 362 is inserted into the gear 363. The gear 363 and the second end of the transmission shaft 362 are engaged by a key 363a. Therefore, the gear 363 can rotate integrally with the transmission shaft 362.

[0145] The teeth of the gear 363 mesh with the shaft-side gear 361 a of the operation shaft 361 . The rotation of the shaft-side gear 361 a is transmitted to the transmission shaft 362 via the gear 363 .

[0146] The first nut 364 has an internal thread portion 364a on the inner circumferential surface. The internal thread portion 364a of the first nut 364 is screwed with the first external thread portion 362b of the transmission shaft 362. In addition, a portion of the outer circumferential surface of the first nut 364 is engaged with the sleeve 343a of the pin moving portion 34a, so that the rotation of the first nut 364 is prevented. Such a first nut 364 moves in the axial direction by the rotation of the transmission shaft 362. That is, the transmission shaft 362 and the first nut 364 constitute a lead screw mechanism that converts the rotation of the transmission shaft 362 into the axial movement of the first nut 364.

[0147] In the arm connection state ( Figure 3 and Figure 4 In the state shown in FIG. 1 , the internal thread portion 364a of the first nut 364 and the first end portion ( Figure 3 and Figure 4 The right end portion in the middle is screwed together.

[0148] The second nut 365 has an internal thread portion 365a on its inner circumferential surface. The internal thread portion 365a of the second nut 365 is threadedly engaged with the second external thread portion 362c of the transmission shaft 362. In addition, a portion of the outer circumferential surface of the second nut 365 is engaged with the sleeve 343b of the pin moving portion 34b.

[0149] Therefore, the rotation of the second nut 365 is prevented. Such a second nut 365 moves in the axial direction by the rotation of the transmission shaft 362. That is, the transmission shaft 362 and the second nut 365 constitute a lead screw mechanism that converts the rotation of the transmission shaft 362 into the axial movement of the second nut 365. In addition, when the transmission shaft 362 rotates in the first direction, the first nut 364 moves to one side in the axial direction, and the second nut 365 moves to the other side in the axial direction. Therefore, the movement direction of the first nut 364 is opposite to the movement direction of the second nut 365.

[0150] In the arm connection state ( Figure 3 and Figure 4 In the state shown in FIG. 1 , the internal thread portion 365a of the second nut 365 and the second end portion ( Figure 3 and Figure 4 The left end portion in the middle is screwed together.

[0151] Next, the operation of the second transmission unit 36 ​​will be described. First, in the arm connection state, the operator Figure 3 As shown in FIG. 1 , the front end portion of the tool T is engaged with the operating portion 33 b 1 . Next, the operator rotates the tool T in the first rotation direction.

[0152] Then, the operating shaft 361 rotates. The rotation of the operating shaft 361 is transmitted to the transmission shaft 362 via the gear 363. When the transmission shaft 362 rotates, the first nut 364 is threadedly engaged with the first external thread portion 362b and the internal thread portion 364a of the first nut 364 to one side in the axial direction ( Figure 3 , Figure 4 The telescopic arm 21 moves to the left side and the inner side in the width direction of the telescopic arm 21.

[0153] In addition, when the transmission shaft 362 rotates, the second nut 365 is threadedly engaged with the second external thread portion 362c and the internal thread portion 365a of the second nut 365 to the other side in the axial direction ( Figure 3 , Figure 4 The telescopic arm 21 moves to the right side and the inner side in the width direction of the telescopic arm 21.

[0154] When the first nut 364 moves, the sleeve 343a of the pin moving portion 34a moves together with the first nut 364. Since the sleeve 343a is connected to the arm connecting pin 33a1 via the connecting portion 345a, the arm connecting pin 33a1 moves together with the sleeve 343a, and the engagement between the arm connecting pin 33a1 and the pin engaging hole 33c1 is released.

[0155] In addition, when the second nut 365 moves, the sleeve 343b of the pin moving portion 34b moves together with the second nut 365. The sleeve 343b is connected to the arm connecting pin 33a2 via the connecting portion 345b, so the arm connecting pin 33a2 moves together with the sleeve 343b, thereby releasing the engagement between the arm connecting pin 33a2 and the pin engaging hole 33c2. In addition, although not shown in the figure, the second transmission portion 36 may also have a locking mechanism for maintaining the state in which the engagement between the arm connecting pin 33a2 and the pin engaging hole 33c2 is released.

[0156] In the above description, the pin drive mechanism 33b provided in the arm member 21d is described. The arm members 21b, 21c, 21e and 21f have the same pin drive mechanism 33b as the arm member 21d. In addition, the arm members 21b, 21c, 21e and 21f may have the second transmission part 36 in the pin drive mechanism 33b, or may not have the second transmission part 36. For the arm members 21b, 21c, 21e and 21f, the second transmission part 36 may be omitted when there is no need for the operator to manually release the arm connection state. In other words, in a working machine in which the telescopic arm is divided into two parts, the second transmission part only needs to be provided in the arm member on the front end side (inner side) of the pair of divided arm members (for example, the arm members 21c and 21d).

[0157] In the mobile crane 1 configured as described above, the telescopic arm 21 performs a telescopic operation by driving the arm telescopic mechanism 30 (telescopic cylinder 31, cylinder-arm connection mechanism 32, and arm connection mechanism 33). When the telescopic arm 21 performs an extension operation, the arm members 21b to 21f in a state of being accommodated in the arm members 21a to 21e located at the base end side are moved in sequence from the arm member located at the most front end side. In addition, when the telescopic arm 21 performs a contraction operation, the arm members 21b to 21f in a state of extending from the arm members 21a to 21e located at the base end side are moved in sequence from the arm member located at the most base end side.

[0158] When the mobile crane 1 is moved between a storage location and a work location, the vehicle body 10 with the telescopic arm 21 removed may be driven, and the telescopic arm 21 may be split into two parts, which are then transported separately using a transport vehicle such as a trailer.

[0159] When the telescopic arm 21 is split into two parts, the operator of the crane device 20 moves the fourth boom 21d to a predetermined telescopic position relative to the third boom 21c. The predetermined telescopic position of the telescopic arm 21 is a telescopic position in which the operating portion 33b1 protruding from the outer side surface of the fourth boom 21d is located inside the opening 33d of the third boom 21c. At this time, the operating portion 33b1 is located near the outer side surface of the third boom 21c (slightly inside the outer side surface). In addition, when the telescopic arm 21 is split into two parts, the arm parts 21d to 21f located at the front end side of the telescopic arm 21 are supported by other crane devices and the like.

[0160] Thereafter, the operator inserts the front end of the tool T from the opening 33d, and fits the front end of the tool T with the operating portion 33b1. After fitting the front end of the tool T with the operating portion 33b1, the operator uses the tool T to operate the operating portion 33b1, thereby rotating the operating shaft 361. At this time, the pin drive mechanism 33b is driven by the rotation of the operating shaft 361, so that the pair of arm connecting pins 33a1 and 33a2 move inward in the width direction of the fourth segment arm 21d. As a result, the connection between the third segment arm 21c and the fourth segment arm 21d in the telescopic arm 21 by the pair of arm connecting pins 33a1 and 33a2 is released, so that the telescopic arm 21 can be separated into two parts.

[0161] As described above, according to the crane apparatus of the present embodiment, the operation portion 33 b 1 is arranged in the vicinity of the outer surfaces of the arm members 21 a to 21 e .

[0162] Thus, the operator who performs the separate operation of the telescopic arm 21 can easily engage the tip of the tool T with the operating portion 33 b 1 , and thus the work efficiency of the separate operation of the telescopic arm 21 can be improved.

[0163] One end of the operating portion 33b1 is connected to the pin drive mechanism 33b and is provided on the operated surface of the operating shaft 361 extending from the pin drive mechanism 33b to the outer surface of the arm members 21b to 21f. The second end of the operating shaft 361 is supported by the bearing 361b.

[0164] Thus, it is possible to suppress the deflection of the operating shaft 361 when operating the operating portion 33b1 provided on the end surface of the second end portion of the operating shaft 361, thereby improving the operability of the operating portion 33b1. In addition, when operating the operating portion 33b1, the bending stress acting on the operating shaft 361 mainly acts on the second end portion side of the operating shaft 361, thereby reducing the load acting on the pin drive mechanism 33b via the operating shaft 361, thereby improving the durability of the pin drive mechanism 33b.

[0165] In addition, in the above embodiment, the crane device 20 is shown in which the telescopic arm 21 is telescopically extended by one telescopic cylinder, but the present invention is not limited to this. As long as the telescopic arm is separable, the present invention can be applied thereto, for example, the present invention can be applied to a crane device that is telescopically extended by two or more telescopic cylinders.

[0166] Furthermore, in the above-described embodiment, the telescopic arm 21 is divided into two parts, but the present invention is not limited thereto, and the present invention may also be applied to a telescopic arm that can be divided into three or more parts.

Claims

1. A working machine having a telescopic arm capable of being extended and retracted by sequentially moving a plurality of arm members, the working machine comprising: A connecting pin that connects adjacent arm members to each other or disconnects adjacent arm members from each other; a pin moving portion that moves the connecting pin by using either a first power or a second power, thereby releasing the engagement between the adjacent arm members; a first transmission part that receives the first power and transmits the first power to the pin moving part; as well as a second transmission unit that receives the second power and transmits the second power to the pin moving unit; The pin moving part is fixed to the fixing part of the arm member through a support member, The first power is power input from an actuator disposed inside the telescopic arm to the first transmission part. The second power is the power input from the outside of the telescopic arm to the second transmission part through manual operation of the operator. The second transmission unit includes an operation shaft that is rotatably supported by the arm member and rotated by the second power and is rotationally transmitted to the pin moving unit. The operating shaft is connected to the connecting pin, The outer arm member of the adjacent arm members has an opening at a predetermined position in the axial direction of the outer arm member. When the inner arm member of the adjacent arm members is moved to a predetermined telescopic position relative to the outer arm member, the end of the operation shaft is arranged inside the opening. When the inner arm part is moved to the telescopic position, if the operating shaft is rotated by a tool inserted from the opening, the connecting pin moves due to the rotation of the operating shaft, thereby releasing the connection between adjacent arm parts, and the adjacent arm parts are able to be separated from each other.

2. The working machine according to claim 1, wherein: The operating shaft has an operating portion connectable to a tool at a position accessible from the outside of the telescopic arm.

3. The working machine according to claim 2, wherein: The second transmission unit includes a transmission shaft that transmits the rotation of the operating shaft to the pin moving unit. The operating shaft extends in the width direction of the telescopic arm, a first end portion thereof is connected to the transmission shaft, and a second end portion thereof is rotatably supported by a side plate portion of the telescopic arm. The operating portion is disposed at the second end portion of the operating shaft.

4. The working machine according to claim 3, wherein: The operating portion protrudes from the side plate portion toward the outside of the telescopic arm.

5. The working machine according to any one of claims 1 to 4, wherein: The second end portion of the operating shaft is supported by a side plate portion in the width direction of the telescopic arm.

6. The working machine according to claim 1, wherein: The connecting pin is supported by the side plate portion of the telescopic arm, The operation shaft is supported by a side plate portion that is the same side plate portion as the side plate portion that supports the connection pin.

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