Work equipment

Abstract

This work machine comprises: a plurality of booms that extend and contract by means of power of an actuator; a boom coupling pin which is supported by the booms, moves in the entering direction by means of a spring to turn into an entering state in which adjacent booms are coupled, and moves in the pulling direction by means of power of a motor to turn into a pulling state in which the coupling is released; and a manual operation member inserted into the boom coupling pin and disposed coaxially with the boom coupling pin. As the manual operation member rotates on the basis of the manual operation of an operator, the boom coupling pin moves in the pulling direction together with the manual operation member, and the coupling between adjacent booms is released.

Description

[Technical Field]

[0001] The present invention relates to a work machine equipped with a telescopic boom. [Background technology]

[0002] Patent Document 1 discloses a mobile crane equipped with a telescopic boom in which multiple booms are nested one on top of the other, and a hydraulic actuator (telescopic cylinder) that extends the telescopic boom.

[0003] Adjacent booms are connected to each other by a connecting pin. A boom that is released from the connection by the connecting pin (hereinafter referred to as a movable boom) becomes movable in the extension / retraction direction relative to the other booms.

[0004] The actuator is connected to the movable boom via a connecting pin, and when the actuator moves in the extension / retraction direction, the movable boom moves together with the actuator, causing the telescopic boom to extend or retract. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-96928 Summary of the Invention [Problem to be solved by the invention]

[0006] In the above-described crane, if the mechanism connecting adjacent booms fails, it may become impossible to release the connection between the booms, making it impossible to retract the telescopic boom.

[0007] An object of the present invention is to provide a work machine equipped with a mechanism that allows adjacent booms to be manually disconnected from each other. [Means for solving the problem]

[0008] One aspect of the working machine according to the present invention is A plurality of booms that are extended and retracted by the power of actuators; a boom connecting pin that is supported by the boom and moves in a retracting direction by a spring to enter an retracted state in which adjacent booms are connected, and moves in a retracting direction by the power of a motor to enter an unretracted state in which the connection is released; a manual operation member that is inserted through the boom connecting pin and is arranged coaxially with the boom connecting pin, When the manual operation member is rotated based on manual operation by the operator, the boom connecting pin moves in the removal direction together with the manual operation member, and the connection between adjacent booms is released. When implementing the above-described work machine, the work machine may preferably include a support member that has a support-side screw hole and supports the boom connecting pin on the boom. In this case, the manual operation member may be configured to be threadedly engaged with the support-side screw hole, and to be able to convert its own rotation into movement in the removal direction based on this threaded engagement. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a work machine equipped with a mechanism that allows adjacent booms to be manually disconnected from each other. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic diagram of a mobile crane according to an embodiment. [Figure 2A] FIG. 2A is a schematic diagram for explaining the structure and extension / retraction operation of a telescopic boom. [Figure 2B] FIG. 2B is a schematic diagram for explaining the structure and extension / retraction operation of the telescopic boom. [Figure 2C] FIG. 2C is a schematic diagram for explaining the structure and extension / retraction operation of the telescopic boom. [Figure 2D] FIG. 2D is a schematic diagram for explaining the structure and extension / retraction operation of the telescopic boom. [Figure 2E] FIG. 2E is a schematic diagram for explaining the structure and extension / retraction operation of the telescopic boom. [Figure 3] FIG. 3 is a schematic diagram for explaining the structure of the telescopic boom. [Figure 4]FIG. 4 is a cross-sectional view of the pin moving mechanism when the boom connection mechanism is in a contracted state. [Figure 5A] 5A is an enlarged cross-sectional view of the X portion in FIG. 4, showing the boom connecting pin in an engaged state. [Figure 5B] 5B is an enlarged cross-sectional view of the portion X in FIG. 4, showing a state in which the boom connecting pin has been manually removed. [Figure 6] FIG. 6 is a perspective view of a boom connecting pin. [Figure 7A] FIG. 7A is a schematic diagram for explaining the operation of the cylinder coupling mechanism. [Figure 7B] FIG. 7B is a schematic diagram for explaining the operation of the cylinder coupling mechanism. [Figure 7C] FIG. 7C is a schematic diagram for explaining the operation of the cylinder coupling mechanism. [Figure 8A] FIG. 8A is a schematic diagram for explaining the operation of the boom connecting mechanism. [Figure 8B] FIG. 8B is a schematic diagram for explaining the operation of the boom connecting mechanism. [Figure 8C] FIG. 8C is a schematic diagram for explaining the operation of the boom connecting mechanism. DETAILED DESCRIPTION OF THE INVENTION

[0011] An example of an embodiment of the present invention will be described in detail below with reference to the drawings. Note that the crane according to the embodiment described below is an example of a work machine according to the present invention, and the present invention is not limited to the embodiment described below.

[0012] [Embodiment] An overview of a mobile crane 1 according to this embodiment will be described with reference to Figs. 1 and 2A to 2E.

[0013] The mobile crane may be, for example, a rough terrain crane, an all-terrain crane, a truck crane, or a loaded truck crane. However, the work machine is not limited to a mobile crane and may be various work machines (for example, aerial work platforms) equipped with a telescopic boom.

[0014] The mobile crane 1 has a telescopic boom 14 and an actuator 2. The telescopic boom 14 has multiple booms combined so that they can be extended and retracted. Adjacent booms are connected to each other by boom connecting pins 15a and 15b.

[0015] When extending or retracting the telescopic boom 14, the actuator 2 moves the boom in the extension / retraction direction. At this time, the actuator 2 is connected to the boom to be moved via the cylinder connecting pins 454A, 454B, and releases the connection between the boom to be moved and the boom adjacent to the boom to be moved.

[0016] During the extension and retraction operation of the telescopic boom 14, the boom connecting pins 15a, 15b move by the power of the electric motor 41 to release the connection between adjacent booms. If a problem occurs with the electric motor 41 at this time, the boom connecting pins 15a, 15b cannot be moved, and the connection between adjacent booms cannot be released. Therefore, the mobile crane 1 is provided with a means (non-release means) for manually moving the boom connecting pins 15a, 15b to release the connection between adjacent booms. The configuration of the mobile crane 1 according to this embodiment will be specifically described below.

[0017] As shown in FIGS. 1 and 2A to 2E, the mobile crane 1 includes a traveling body 10, a swivel base 12, a telescopic boom 14, an actuator 2, a wire rope 16, and a hook 17.

[0018] The swivel base 12 is provided on the upper part of the traveling body 10. The base end of the telescopic boom 14 is fixed to the swivel base 12 and is capable of raising and lowering and extending. The actuator 2 extends and retracts the telescopic boom 14. The wire rope 16 is supported by the telescopic boom 14 and hangs down from the tip of the telescopic boom 14. The hook 17 is provided at the tip of the wire rope 16.

[0019] Next, we will explain the telescopic boom 14. The telescopic boom 14 has multiple booms combined telescopically. The multiple booms are, from the inside out, a tip boom 141, an intermediate boom 142, and a base boom 143.

[0020] The telescopic boom 14 extends in order from the innermost boom, thereby transitioning from the contracted state shown in Fig. 2A to the extended state shown in Fig. 1. There may be multiple intermediate booms.

[0021] The tip boom 141 has a pair of cylinder pin receiving portions 141a and a pair of boom pin receiving portions 141b at its base end. The pair of cylinder pin receiving portions 141a are provided coaxially with each other at the base end of the tip boom 141. The pair of cylinder pin receiving portions 141a are respectively engageable with and disengageable from a pair of cylinder connecting pins 454A, 454B provided on the cylinder member 32 (movable member) of the telescopic cylinder 3.

[0022] With the pair of cylinder connecting pins 454A, 454B engaged with the pair of cylinder pin receiving portions 141a, the tip boom 141 can move together with the cylinder member 32 in the extension / contraction direction.

[0023] The pair of boom pin receiving portions 141b are provided coaxially around the cylinder pin receiving portion 141a. The boom pin receiving portions 141b respectively support a pair of boom connecting pins 15a. For ease of explanation, the pair of boom pin receiving portions 141b and the pair of cylinder pin receiving portions 141a are shown as being offset in the axial direction of the telescopic boom 14. However, the pair of boom pin receiving portions 141b and the pair of cylinder pin receiving portions 141a are aligned in the axial direction of the telescopic boom 14 and are provided at offset positions in the circumferential direction of the telescopic boom 14.

[0024] The pair of boom connecting pins 15a each connect the tip boom 141 and the intermediate boom 142. The pair of boom connecting pins 15a move inward (in the direction from the tip end to the base end of the boom connecting pins 15a) based on the operation of the boom connecting mechanism 46, which will be described later. The specific structure of the pair of boom connecting pins 15a will be described later.

[0025] With the tip boom 141 and the intermediate boom 142 connected by a pair of boom connecting pins 15a, the boom connecting pin 15a is inserted so as to span between the boom pin receiving portion 141b of the tip boom 141 and the first boom pin receiving portion 142b or the second boom pin receiving portion 142c of the intermediate boom 142. In other words, the pair of boom connecting pins 15a can be engaged with and disengaged from the first boom pin receiving portion 142b or the second boom pin receiving portion 142c of the intermediate boom 142, respectively.

[0026] The intermediate boom 142 has a pair of cylinder pin receiving portions 142a, a pair of first boom pin receiving portions 142b, and a pair of third boom pin receiving portions 142d at its base end, and a pair of second boom pin receiving portions 142c at its tip end.

[0027] For ease of explanation, the illustration shows the pair of first boom pin receiving portions 142b and the pair of cylinder pin receiving portions 142a as being offset in the axial direction of the telescopic boom 14. However, the pair of first boom pin receiving portions 142b and the pair of cylinder pin receiving portions 142a are aligned in the axial direction of the telescopic boom 14 and are provided at offset positions in the circumferential direction of the telescopic boom 14.

[0028] A pair of boom connecting pins 15b are inserted into the pair of third boom pin receiving portions 142d, respectively. The pair of boom connecting pins 15b connect the intermediate boom 142 and the base boom end 143 together.

[0029] The pair of second boom pin receiving portions 142c are provided coaxially with each other at the tip of the intermediate boom 142. A pair of boom connecting pins 15a are inserted into the pair of second boom pin receiving portions 142c, respectively.

[0030] 3, the intermediate boom 142 has a pair of emergency operation holes 142e for cylinder pins at positions that are coaxial with the pair of cylinder pin receiving portions 141a of the tip boom 141 when the telescopic boom 14 is in a retracted state. The base boom 143 has a pair of emergency operation holes 143a for cylinder pins at positions that are coaxial with the pair of cylinder pin receiving portions 141a of the tip boom 141 when the telescopic boom 14 is in a retracted state.

[0031] The base end boom 143 has a pair of emergency operation holes 143b for cylinder pins at positions that are coaxial with the pair of cylinder pin receiving portions 142a of the intermediate boom 142 when the telescopic boom 14 is in a contracted state.

[0032] When manually operating to manually move the pair of cylinder connecting pins 454A, 454B, an operator can access the pair of cylinder connecting pins 454A, 454B engaged with the pair of cylinder pin receiving portions 141a of the tip boom 141 or the pair of cylinder pin receiving portions 142a of the intermediate boom 142 from the outside of the telescopic boom 14 through the emergency operation holes 142e, 143a, 143b for the cylinder pins.

[0033] Furthermore, the intermediate boom 142 and the base boom 143 have boom pin emergency operation holes 143c, 143d at positions that are coaxial with the boom pin receiving portions of all the booms arranged inside when the telescopic boom 14 is in a retracted state. In the case of the telescopic boom 14 shown in the figure, since there is only one intermediate boom, the boom pin emergency operation holes 143c, 143d are provided only on the base boom 143. However, if there are multiple intermediate booms, the boom pin emergency operation holes may be provided at appropriate positions on the intermediate booms.

[0034] When manually operating to manually move the boom connecting pin (e.g., boom connecting pin 15a), the operator can access the boom connecting pin (e.g., boom connecting pin 15a) from the outside of the telescopic boom 14 through the emergency operation holes 143c, 143d for the boom pin.

[0035] In this embodiment, the cylinder pin emergency operation hole 143b and the boom pin emergency operation holes 143c and 143d are provided on the same surface of the boom, so that an operator can manually operate the cylinder connecting pin and the boom connecting pin from the same direction.

[0036] The actuator 2 is an actuator that extends and retracts the telescopic boom 14. As shown in FIGS. 2A to 2E and 4, the actuator 2 has a telescopic cylinder 3 and a pin moving mechanism 4. The actuator 2 is disposed in the internal space of the tip boom 141 when the telescopic boom 14 is in the retracted state (the state shown in FIG. 2A).

[0037] The telescopic cylinder 3 has a rod member 31 and a cylinder member 32. The telescopic cylinder 3 moves a boom connected to the cylinder member 32 via cylinder connecting pins 454A and 454B, which will be described later.

[0038] The pin moving mechanism 4 has an electric motor 41 , a brake mechanism 42 , a transmission mechanism 43 , a position information detection device 44 , a cylinder connecting mechanism 45 , and a boom connecting mechanism 46 , all of which are supported by a trunnion 40 .

[0039] Hereinafter, each member constituting the actuator 2 will be described based on the state in which each member is incorporated into the actuator 2. In addition, in the description of the actuator 2, a Cartesian coordinate system (X, Y, Z) will be used.

[0040] In the Cartesian coordinate system, the X direction corresponds to the extension direction of the telescopic boom 14 when it is mounted on the mobile crane 1. The positive side of the X direction is the extension direction in the telescopic direction. The negative side of the X direction is the contraction direction in the telescopic direction. When the rotation angle of the telescopic boom 14 is 0° and the hoisting angle of the telescopic boom 14 is 0° (fully lowered state), the positive side of the X direction corresponds to the front side of the mobile crane 1. When the rotation angle of the telescopic boom 14 is 0° and the hoisting angle of the telescopic boom 14 is 0°, the negative side of the X direction corresponds to the rear side of the mobile crane 1.

[0041] Furthermore, for example, when the hoisting angle of the telescopic boom 14 is 0°, the Z direction corresponds to the up-down direction of the mobile crane 1. For example, when the telescopic boom 14 is facing forward, the Y direction corresponds to the vehicle width direction (left-right direction) of the mobile crane 1. Hereinafter, when reference is made to the width direction or left-right direction without any particular mention, this refers to the Y direction in the Cartesian coordinate system (X, Y, Z).

[0042] The trunnion 40 is fixed to the cylinder member 32 of the telescopic cylinder 3. As shown in Fig. 4, the trunnion 40 supports a cylinder connection mechanism 45 and a boom connection mechanism 46. The trunnion 40 also supports an electric motor 41, a brake mechanism 42, and a transmission mechanism 43. Fig. 4 is a cross-sectional view showing the telescopic boom 14 and the pin moving mechanism 4 cut along a plane (ZY plane) perpendicular to the direction in which the telescopic boom 14 extends and retracts. For ease of explanation, some components are omitted in Fig. 4. Hatching indicating a cross section is also omitted in Fig. 4.

[0043] The trunnion 40 unitizes the above elements 41 to 46. Such a configuration contributes to the miniaturization of the pin moving mechanism 4, improvement of productivity, and improvement of system reliability. In particular, in the case of this embodiment, the cylinder connecting mechanism 45, boom connecting mechanism 46, and electric motor 41 are arranged side by side in the vertical direction. This allows the pin moving mechanism 4 to be miniaturized in the extension / retraction direction (X direction) of the telescopic boom 14.

[0044] The trunnion 40 has a support hole 401. The rod member 31 of the telescopic cylinder 3 is inserted into the support hole 401 in the X direction. The trunnion 40 is fixed to the base end (the end on the negative side in the X direction) of the cylinder member 32 of the telescopic cylinder 3. Therefore, the trunnion 40 can move together with the cylinder member 32.

[0045] The electric motor 41 is supported by the trunnion 40 (see FIG. 4). Specifically, the electric motor 41 is supported at the upper end of the trunnion 40 with its output shaft parallel to the extension / retraction direction (X direction) of the telescopic boom 14. As shown in FIG. 7A, the electric motor 41 is connected to a reducer 431. The electric motor 41 is connected to, for example, a power supply device (not shown) provided on the swivel base 12 via a power supply cable.

[0046] The brake mechanism 42 applies a braking force to the electric motor 41. When the electric motor 41 is stopped, the brake mechanism 42 prevents the rotation of the output shaft of the electric motor 41. This maintains the state of the pin moving mechanism 4 when the electric motor 41 is stopped. The reducer 431 and the brake mechanism 42 are provided coaxially with the electric motor 41.

[0047] Specifically, the brake mechanism 42 operates when the cylinder coupling mechanism 45 or the boom coupling mechanism 46, which will be described later, is in a retracted state, to maintain the states of the cylinder coupling mechanism 45 and the boom coupling mechanism 46. The state of the brake mechanism 42 is switched by a control unit. Alternatively, the state of the brake mechanism 42 may be switched based on an operation by an operator.

[0048] The transmission mechanism 43 transmits the power of the electric motor 41 to the cylinder connecting mechanism 45 and the boom connecting mechanism 46. The transmission mechanism 43 includes a reducer 431 and a transmission shaft 432.

[0049] The reducer 431 reduces the rotation of the electric motor 41 and transmits the reduced rotation to a transmission shaft 432. The transmission shaft 432 transmits the rotation of the reducer 431 to a switch gear 450, which will be described later. In addition, a position information detection device 44 is provided at the tip of the transmission shaft 432, which detects information relating to the positions of the pair of cylinder connecting pins 454A, 454B and the pair of boom connecting pins 15a, 15b.

[0050] The information relating to the positions of the pair of cylinder connecting pins 454A, 454B and the pair of boom connecting pins 15a, 15b is, for example, the amount of movement of the pair of cylinder connecting pins 454A, 454B or the pair of boom connecting pins 15a, 15b from a reference position. The positions of the pair of cylinder connecting pins 454A, 454B shown in Fig. 7A are the reference positions of the cylinder connecting pins 454A, 454B. Furthermore, the position of the pair of boom connecting pins 15a shown in Fig. 8A is the reference position of the boom connecting pin 15a.

[0051] The cylinder coupling mechanism 45 operates based on the power of the electric motor 41, and transitions between an expanded state (see FIG. 7A) and a contracted state (see FIG. 7C). The operation of the cylinder coupling mechanism 45 transitioning from the expanded state to the contracted state is the extraction operation of the cylinder coupling mechanism 45. The operation of the cylinder coupling mechanism 45 transitioning from the contracted state to the expanded state is the engagement operation of the cylinder coupling mechanism 45.

[0052] When the cylinder connecting mechanism 45 is in the expanded state, the pair of cylinder connecting pins 454A, 454B and the pair of cylinder pin receiving portions 141a of the boom (for example, the tip boom 141) are engaged with each other. In this engaged state, the boom and the cylinder member 32 are connected to each other.

[0053] Furthermore, when the cylinder connecting mechanism 45 is in the contracted state, the pair of cylinder connecting pins 454A, 454B and the pair of cylinder pin receiving portions 141a are in a disengaged state. In this disengaged state, the boom and the cylinder member 32 are disengaged.

[0054] Specifically, the cylinder connecting mechanism 45 includes a switch gear 450, a first transmission mechanism 451, a pair of cylinder connecting pins 454A and 454B, and a first biasing mechanism 455.

[0055] The switch gear 450 is fitted and fixed to the outside of the transmission shaft 432 and selectively transmits the power of the electric motor 41 to either the cylinder connection mechanism 45 or the boom connection mechanism 46 .

[0056] Here, the rotation direction of the switch gear 450 when the cylinder coupling mechanism 45 transitions from the extended state to the contracted state (the direction indicated by the arrow A1 in FIG. 7A) is defined as a first rotation direction of the switch gear 450. Also, the rotation direction of the switch gear 450 when the cylinder coupling mechanism 45 transitions from the contracted state to the extended state (the direction indicated by the arrow A2 in FIG. 7C) is defined as a second rotation direction of the switch gear 450.

[0057] The first transmission mechanism 451 is configured by, for example, a rack bar, gears, etc. The first transmission mechanism 451 transmits a driving force according to the rotation of the switch gear 450 to the cylinder connecting pins 454A and 454B.

[0058] The pair of cylinder connecting pins 454A, 454B have respective central axes that coincide in the left-right direction and are coaxial with each other. The pair of cylinder connecting pins 454A, 454B are each supported by the trunnion 40. The pair of cylinder connecting pins 454A, 454B are configured to be movable in their own axial direction based on the power of the electric motor 41 or the biasing force of the first biasing mechanism 455.

[0059] The first biasing mechanism 455 is configured by a pair of coil springs, and returns the cylinder coupling mechanism 45 to the expanded state when the electric motor 41 is de-energized while the cylinder coupling mechanism 45 is in the contracted state.

[0060] 7A, when the switch gear 450 rotates in a first rotation direction based on the power of the electric motor 41, the first transmission mechanism 451 transmits a driving force to each of the cylinder connecting pins 454A and 454B to move the cylinder connecting pins 454A and 454B inward. As a result, the cylinder connecting mechanism 45 enters a contracted state.

[0061] 7C, when the switch gear 450 rotates in the second rotation direction based on the biasing force of the first biasing mechanism 455, the cylinder coupling mechanism 45 transmits a driving force to each of the cylinder coupling pins 454A, 454B to move the cylinder coupling pins 454A, 454B outward. As a result, the cylinder coupling mechanism 45 enters the expanded state.

[0062] The boom connection mechanism 46 transitions between an extended state (see FIG. 8A) and a retracted state (see FIG. 8C) based on the rotation of the electric motor 41. The operation of the boom connection mechanism 46 transitioning from the extended state to the retracted state is the retracting operation of the boom connection mechanism 46. The operation of the boom connection mechanism 46 transitioning from the retracted state to the extended state is the retracting operation of the boom connection mechanism 46.

[0063] The boom connecting pin 15a is a pin for connecting the inner boom (the boom tip 141 or the intermediate boom 142) and the outer boom (the intermediate boom 142 or the boom base 143). The boom connecting pin 15a is supported by the inner boom. The specific configuration of the boom connecting pin 15a will be described later.

[0064] In the extended state, the boom connection mechanism 46 can engage with boom connection pins (for example, a pair of boom connection pins 15a). When the boom connection mechanism 46 is engaged with the boom connection pins, it transitions from the extended state to the retracted state, thereby disengaging the boom connection pins from the outer boom. Note that the following description will be given with reference to the boom connection pin 15a as an example of a boom connection pin. The boom connection pin may also be the boom connection pin 15b.

[0065] Furthermore, the boom connection mechanism 46, while engaged with the boom connection pin 15a, transitions from the contracted state to the extended state, thereby engaging the boom connection pin 15a with the outer boom.

[0066] 8A to 8C, the boom connection mechanism 46 has a switch gear 450 and a second transmission mechanism 461. The switch gear 450 is a gear that is shared with the cylinder connection mechanism 45.

[0067] The second transmission mechanism 461 is configured by, for example, a rack bar, gears, etc. In a state where the second transmission mechanism 461 is engaged with the boom connecting pins 15a, the second transmission mechanism 461 transmits a driving force corresponding to the rotation of the switch gear 450 to each of the pair of boom connecting pins 15a. In other words, the second transmission mechanism 461 moves the pair of boom connecting pins 15a simultaneously.

[0068] When the switch gear 450 rotates in the second rotation direction A2 while the boom connection mechanism 46 is in the extended state (see FIG. 8A), the second transmission mechanism 461 moves the boom connection pins 15a inward, and the boom connection mechanism 46 then enters the retracted state (see FIG. 8C).

[0069] When the switch gear 450 rotates in the first rotation direction A1 while the boom connection mechanism 46 is in the contracted state, the second transmission mechanism 461 moves each of the boom connection pins 15a outward, and the boom connection mechanism 46 then enters the extended state.

[0070] Here, the structure of the boom connecting pin 15a will be described with reference to Figures 4 to 6. The boom connecting pin 15a is configured to be movable in the axial direction. Figure 5A shows the boom connecting pin 15a in its outermost position (one end of its axial movement stroke). The state in which the boom connecting pin 15a is positioned outermost is also referred to as the boom connecting pin 15a's engaged state.

[0071] 5B shows a state in which the boom connecting pin 15a is positioned at the innermost position (the other end of the axial movement stroke). The state in which the boom connecting pin 15a is positioned at the innermost position is also referred to as the removed state of the boom connecting pin 15a.

[0072] 2A and other figures, a pair of boom connecting pins is provided on each of the inner booms (the tip boom 141 and the intermediate boom 142 in this embodiment) disposed inside the base boom 143. All of the boom connecting pins have substantially the same configuration as the boom connecting pin 15a.

[0073] The following description will focus on the right boom connecting pin 15a of the pair of boom connecting pins 15a provided on the tip boom 141. However, the left boom connecting pin 15a of the pair of boom connecting pins 15a has the same configuration as the boom connecting pin 15a.

[0074] The boom connecting pin 15 a has a pin body 150 , a first coil spring 151 , a second coil spring 152 , a manual operation member 153 , and a locking claw portion 154 .

[0075] The pin body 150 is a substantially cylindrical member that is configured to be movable in the axial direction. The pin body 150 can also be regarded as a boom connecting pin.

[0076] In the following description, the tip side refers to one end side of the pin body 150 in the axial direction (the right side in Figures 5A and 5B). The base side refers to the other end side of the pin body 150 in the axial direction (the left side in Figures 5A and 5B). One end side of the pin body 150 in the axial direction corresponds to the outer side in the vehicle width direction of the mobile crane 1. The other end side of the pin body 150 in the axial direction corresponds to the inner side in the vehicle width direction of the mobile crane 1. The axial direction of the pin body 150 is also the movement direction of the boom connecting pin 15a. In this embodiment, the axial direction of the pin body 150 coincides with the left-right direction of the mobile crane 1. Note that the axial direction of the pin body 150 may also coincide with the up-down direction of the mobile crane 1.

[0077] The pin body 150 has a first accommodating portion 150a in its tip (outer) half. The tip (outer end) of the first accommodating portion 150a opens to the tip face (outer end face) of the pin body 150. The central axis of the first accommodating portion 150a is parallel to the axial direction and coincides with the central axis of the pin body 150.

[0078] The pin body 150 has a second accommodating portion 150b in the base end (inner) half. The central axis of the second accommodating portion 150b is parallel to the axial direction and coincides with the central axis of the pin body 150. Therefore, the central axis of the second accommodating portion 150b coincides with the central axis of the first accommodating portion 150a. The first accommodating portion 150a and the second accommodating portion 150b are separated by a partition portion 150c.

[0079] The partition portion 150c is plate-shaped and has a pin-side through-hole 150d that passes through the partition portion 150c in the axial direction. The central axis of the pin-side through-hole 150d coincides with the central axes of the first accommodating portion 150a and the second accommodating portion 150b.

[0080] The pin body 150 has a pair of slits 150e, 150f at its base end. The slits 150e, 150f each extend from the base end to the tip end of the pin body 150. The lengths of the slits 150e, 150f (the axial length of the pin body 150) are set according to the axial movement stroke of the boom connecting pin 15a.

[0081] The slit 150e is provided at the upper end of the pin body 150. The slit 150f is provided at the lower end of the pin body 150. The slits 150e and 150f face each other in the vertical direction.

[0082] The pin body 150 having the above-described configuration is held in the boom pin receiving portion 141b of the tip boom end 141. The boom pin receiving portion 141b is configured as a cylindrical sleeve fixed to the tip boom end 141. The boom pin receiving portion 141b is fixed to the tip boom end 141 by welding.

[0083] A support member 144 is fixed to the boom pin receiving portion 141b. The support member 144 is a plate-like member that extends in the vertical direction, and is fixed to the boom pin receiving portion 141b via fastening parts such as bolts. Specifically, the support member 144 is made up of a single plate-like member, and is fixed to the boom pin receiving portion 141b by fastening parts 144c (bolts in the illustrated case) inserted through the upper and lower ends.

[0084] The support member 144 is a member for supporting the pin body 150 with respect to the boom. The support member 144 is also a member for guiding the movement of the pin body 150 in the axial direction.

[0085] The support member 144 is inserted from above and below through the slits 150e and 150f of the pin body 150. The width of the support member 144 is slightly smaller than the width of the slits 150e and 150f. The axial movement of the pin body 150 is guided by the engagement between the support member 144 and the slits 150e and 150f.

[0086] In this embodiment, the support member 144 is inserted through the slits 150e and 150f from above and below. This configuration contributes to the miniaturization of the structure for supporting the boom connection pin 15a on the boom pin receiving portion 141b. Fasteners 144c for fixing the support member 144 to the boom pin receiving portion 141b are provided above and below the pin body 150. Therefore, in the state shown in FIG. 5A , when the boom connection mechanism 46 engages with the locking claw portion 154 of the boom connection pin 15a in the telescopic direction (X direction), the boom connection mechanism 46 and the fasteners 144c do not interfere with each other. By providing the fasteners 144c above and below the pin body 150 in this manner, interference between the boom connection mechanism 46 and the fasteners 144c in the telescopic direction can be suppressed without providing a space to avoid interference between the boom connection mechanism 46 and the fasteners 144c. As a result, the structure for supporting the boom connection pin on the boom pin receiving portion 141b can be miniaturized. In addition, in this embodiment, the boom connecting pins 15a, 15b are attached to the telescopic boom 14 from the inside of the telescopic boom 14. Therefore, there is no need to disassemble the telescopic boom 14 when attaching the boom connecting pins 15a, 15b to the telescopic boom 14.

[0087] The support member 144 has a boss portion 144a in the center in the up-down direction. The boss portion 144a protrudes from one end face (outer end face) of the support member 144 toward one side (outside) in the thickness direction of the support member 144. The thickness direction of the support member 144 coincides with the axial direction of the pin body 150 and the vehicle width direction of the mobile crane 1.

[0088] The boss portion 144a has a support-side screw hole 144b at its tip. The central axis of the support-side screw hole 144b coincides with the central axis of the pin-side through-hole 150d. A female thread is provided on the inner circumferential surface of the support-side screw hole 144b. The boss portion 144a is disposed at the base end of the second accommodating portion 150b of the pin body 150 when the boom connecting pin 15a is inserted (the state shown in FIG. 5A).

[0089] Such boss portion 144a is a member for positioning (guiding) first coil spring 151 and second coil spring 152 as will be described later, and is also a member for accommodating nut 153b of manual operation member 153 inside.

[0090] The first coil spring 151 and the second coil spring 152 are biasing members for transitioning the boom connection mechanism 46 from the contracted state to the extended state during normal operation of the boom connection mechanism 46. In other words, the first coil spring 151 and the second coil spring 152 are biasing members for transitioning the boom connection pin 15a from the extracted state to the engaged state during normal operation of the boom connection mechanism 46.

[0091] The first coil spring 151 and the second coil spring 152 are disposed in the second accommodating portion 150b of the pin body 150. The outer diameter of the first coil spring 151 is larger than the outer diameter of the second coil spring 152. The second coil spring 152 is disposed inside the first coil spring 151.

[0092] In other words, the first coil spring 151 and the second coil spring 152 are disposed between the support member 144 and the pin body 150. Specifically, the tip ends (one end in the axial direction) of the first coil spring 151 and the second coil spring 152 abut against the pin body 150 (specifically, the partition portion 150c). The outer peripheral surface of the tip end of the first coil spring 151 is held by the inner peripheral surface of a recess 150g provided at the base end of the pin body 150. With this configuration, the contraction of the first coil spring 151 is guided by the inner peripheral surface of the recess 150g. Furthermore, the outer peripheral surface of the tip end of the second coil spring 152 is held by the first coil spring 151.

[0093] On the other hand, the base ends (other ends in the axial direction) of the first coil spring 151 and the second coil spring 152 abut against the support member 144. The base ends of the first coil spring 151 and the second coil spring 152 are arranged so as to surround the boss portion 144a.

[0094] The first coil spring 151 and the second coil spring 152 are positioned by the boss portion 144a. The first coil spring 151 and the second coil spring 152 constantly bias the pin body 150 in the inserting direction (to one side in the axial direction).

[0095] The manual operation member 153 is a member operated by an operator during manual operation. The manual operation member 153 is operated, for example, by a manual operation tool 5 used by the operator. The manual operation member 153 is inserted into the pin body 150 and is arranged coaxially with the pin body 150. When the manual operation member 153 rotates, the pin body 150 moves together with the manual operation member 153 in the removal direction (the other side in the axial direction), thereby releasing the connection between adjacent booms. Specifically, when the manual operation member 153 rotates, the manual operation member 153 presses the pin body 150 in the removal direction. Then, the pin body 150 moves in the removal direction, thereby releasing the connection between adjacent booms. In this embodiment, the manual operation member 153, which is a member that presses the pin body 150 in the removal direction during manual operation, is constantly incorporated into the boom connecting pin 15a. In other words, the manual operation member 153 is constantly supported by the boom connecting pin 15a. This configuration can prevent the manual operation member 153 from being lost. The manual operation tool 5 is, for example, a socket wrench. The length of the socket wrench may be adjusted appropriately using an extension bar depending on the position of the boom connecting pin to be operated. The type of manual operation tool may be determined appropriately depending on the shape of the head of the manual operation member.

[0096] Specifically, the manual operation member 153 has a bolt 153a and a nut 153b. The bolt 153a has a head 153c and a threaded shaft 153d.

[0097] The threaded shaft portion 153d has a male thread on its outer circumferential surface. The threaded shaft portion 153d is inserted through the pin-side through-hole 150d and the support-side threaded hole 144b. The central axis of the threaded shaft portion 153d coincides with the central axes of the pin-side through-hole 150d and the support-side threaded hole 144b.

[0098] The male threaded portion of the threaded shaft portion 153d is threadedly engaged with the female threaded portion of the support-side threaded hole 144b. One axial end (outer end) of the threaded shaft portion 153d protrudes to one axial side (the right side in FIGS. 5A and 5B) beyond the pin-side through-hole 150d (partition portion 150c). In other words, one axial end (outer end) of the threaded shaft portion 153d is disposed in the first accommodating portion 150a of the pin body 150.

[0099] The other axial end (inner end) of the screw shaft portion 153d protrudes further axially toward the other side (inner side, left side in Figures 5A and 5B) than the support side screw hole 144b (boss portion 144a of the support member 144).

[0100] The head 153c is provided at one axial end (outer end) of the screw shaft portion 153d. Therefore, the head 153c is provided on one axial side (the right side in FIGS. 5A and 5B) of the pin-side through-hole 150d (partition portion 150c). In other words, the head 153c is disposed in the first accommodating portion 150a of the pin body 150. The head 153c is an example of a pressing portion, and is a member that presses the pin body 150 in the removal direction during manual operation.

[0101] The nut 153b is a so-called double nut, and is fixed to the other axial end (inner end) of the threaded shaft portion 153d. Therefore, the nut 153b is disposed on the other axial side (left side in FIGS. 5A and 5B) of the support-side threaded hole 144b (the boss portion 144a of the support member 144). When the boom connecting pin 15a is in the engaged state (the state shown in FIG. 5A), the nut 153b is disposed on the inner side of the boss portion 144a (left side in FIGS. 5A and 5B).

[0102] The manual operation member 153 having the above-described configuration, together with the support-side screw hole 144b, constitutes a conversion mechanism that can convert its own rotational motion into linear motion in the axial direction. When the manual operation member 153 rotates in a predetermined direction, the manual operation member 153 moves in the predetermined axial direction.

[0103] The locking claw portion 154 is fixed to the base end portion of the pin body 150. The locking claw portion 154 is configured to be connectable to the boom connecting mechanism 46.

[0104] The following describes an example of the operation of the boom connection mechanism 46. First, an example of the operation of the boom connection mechanism 46 during normal operation will be described with reference to Figures 2A to 2E, 5A, and 8A to 8C.

[0105] Fig. 8A is a schematic diagram showing the boom connection mechanism 46 in an extended state, and an engaged state between the pair of boom connecting pins 15a and the pair of first boom pin receivers 142b of the intermediate boom 142. Fig. 8B is a schematic diagram showing the boom connection mechanism 46 in the middle of transitioning from the extended state to the retracted state. Furthermore, Fig. 8C is a schematic diagram showing the boom connection mechanism 46 in a retracted state, and a disengaged state between the pair of boom connecting pins 15a and the pair of first boom pin receivers 142b of the intermediate boom 142.

[0106] The extended state of the boom connection mechanism 46 shown in Fig. 8A corresponds to the state of the boom connection mechanism 46 in Fig. 2A. The state of the boom connection pin 15a corresponding to the extended state of the boom connection mechanism 46 shown in Fig. 8A is the retracted state. Fig. 5A shows the boom connection pin 15a in the retracted state.

[0107] 8B corresponds to a state of the boom connection mechanism 46 that is transitioning from the state of the boom connection mechanism 46 shown in FIG. 2A to the state of the boom connection mechanism 46 shown in FIG. 2B.

[0108] The retracted state of the boom connection mechanism 46 shown in Fig. 8C corresponds to the state of the boom connection mechanism 46 shown in Fig. 2B. Moreover, the state of the boom connection pin 15a corresponding to the retracted state of the boom connection mechanism 46 shown in Fig. 8C is the extracted state.

[0109] The boom linkage mechanism 46 transitions between an extended state and a retracted state based on the power of the electric motor 41. Here, the position of the switch gear 450 shown in FIG.

[0110] When the boom connection mechanism 46 transitions from the extended state to the retracted state, the control unit (not shown) drives the electric motor 41 in the direction opposite to the direction in which the cylinder connection mechanism 45 is operated.

[0111] The power of the electric motor 41 is transmitted to a pair of boom connecting pins 15a via a switch gear 450 and a second transmission mechanism 461.

[0112] When the second transmission mechanism 461 transitions from the extended state to the retracted state while engaged with the pair of boom connecting pins 15a, the pair of boom connecting pins 15a disengage from the pair of first boom pin receiving portions 142b of the intermediate boom 142 (see Figure 8C).

[0113] Specifically, when the switch gear 450 rotates in the second rotation direction (the direction indicated by arrow A2 in FIG. 8A) based on the power of the electric motor 41, the right boom connecting pin 15a moves to the left, and the left boom connecting pin 15a moves to the right. At this time, the pair of boom connecting pins 15a move in the pull-out direction.

[0114] In other words, when the second transmission mechanism 461 transitions from the extended state to the contracted state while engaged with the pair of boom connecting pins 15a, the pair of boom connecting pins 15a transition from the engaged state shown in Figure 5A to the disengaged state.

[0115] In the engaged state, the locking claw portion 154 of the boom connecting pin 15a is engaged with the second transmission mechanism 461. In this state, when the locking claw portion 154 is pulled to the left in Fig. 5A by the second transmission mechanism 461, the pin body 150 moves to the left from the position shown in Fig. 5A. At this time, the pin body 150 moves to the left against the biasing forces of the first coil spring 151 and the second coil spring 152. It should be noted that the manual operation member 153 does not move from the position shown in Fig. 5A.

[0116] The position information detecting device 44 detects that the pair of boom connecting pins 15a have been released from the pair of first boom pin receiving portions 142b of the intermediate boom 142 and have moved to a predetermined position (for example, the position shown in FIG. 8C). Then, based on this detection result, the control unit stops the operation of the electric motor 41.

[0117] When the brake mechanism 42 is turned off while the electric motor 41 is not energized, the closing operation of the boom connection mechanism 46 is automatically performed based on the biasing forces of the first coil spring 151 and the second coil spring 152. During this state transition, the pair of boom connection pins 15a move in directions away from each other.

[0118] The position information detection device 44 detects that the pair of boom connecting pins 15a are engaged with the pair of first boom pin receiving portions 142b of the intermediate boom 142 and have moved to a predetermined position (for example, the position shown in FIG. 8C). The detection result is used to control the next operation of the actuator 2.

[0119] Next, we will explain the operation of the boom connection mechanism 46 in an emergency. When the boom connection mechanism 46 is in the extended state shown in Figures 2A, 3, 5A, and 8A, if a problem occurs that prevents the electric motor 41 from operating normally (hereinafter referred to as a "motor problem"; for example, a power loss), the boom connection mechanism 46 cannot be transitioned from the extended state to the retracted state.

[0120] Therefore, in this embodiment, the boom connection mechanism 46 can be transitioned from the extended state to the retracted state by manual operation by the operator. In other words, the pair of boom connection pins 15a can be transitioned from the engaged state to the disengaged state by manual operation by the operator. The reason for this will be explained below.

[0121] 2A, 5A, and 8A, if a problem occurs with the motor, the operator inserts the manual operation bolt 5 (see FIGS. 3 and 5A) into the boom pin emergency operation hole 143c (see FIG. 3) from the outside of the telescopic boom 14. Then, the operator engages the manual operation bolt 5 with the manual operation member 153 of the boom connecting pin 15a. Specifically, the manual operation bolt 5 engages with the head 153c of the manual operation member 153.

[0122] Then, the operator rotates the manual operation bolt 5 in a predetermined direction (first direction). As a result, the manual operation member 153 rotates together with the manual operation bolt 5. When the manual operation member 153 rotates, the manual operation member 153 moves in the axial direction (the left side in FIG. 5A , in the direction in which the boom connecting pin 15a is removed) based on the threaded engagement between the threaded shaft portion 153d of the manual operation member 153 and the support-side threaded hole 144b of the support member 144.

[0123] When the manual operation member 153 moves in the axial direction, the head 153c presses the pin body 150 (specifically, the partition portion 150c) in the direction in which the boom connecting pin 15a is removed. As a result, the pin body 150 moves in the direction in which the boom connecting pin 15a is removed (to the left in FIG. 5A) against the biasing forces of the first coil spring 151 and the second coil spring 152.

[0124] When the operator continues to rotate the manual operation bolt 5 in a predetermined direction (first direction), the innermost ends of the slits 150e and 150f of the pin body 150 (one end in the axial direction, the right end in FIGS. 5A and 5B) come into axial contact with the support member 144. In this state, the boom connecting pin 15a enters the withdrawn state shown in FIG. 5B. In other words, the boom connecting pin 15a is disengaged from the intermediate boom 142. Note that the innermost ends of the slits 150e and 150f come into contact with the support member 144, restricting movement of the pin body 150 in the inserting direction.

[0125] The right boom connecting pin 15a and the left boom connecting pin 15a are connected via a boom connecting mechanism 46. When the above-described manual operation is performed on either the right boom connecting pin 15a or the left boom connecting pin 15a, the other boom connecting pin 15a also moves in the retracting direction in synchronization with the one boom connecting pin 15a. As a result, the right boom connecting pin 15a and the left boom connecting pin 15a simultaneously transition from the engaged state to the retracted state.

[0126] When the operator rotates the manual operation bolt 5 from the state shown in Figure 5B in the direction opposite to the predetermined direction (first direction) (second direction), the boom connecting pin 15a moves in the inserting direction and enters the inserted state shown in Figure 5A.

[0127] Although not shown in the drawings, the mobile crane according to this embodiment also includes a mechanism (manual cylinder pin operating mechanism) for manually releasing the connection between the telescopic cylinder 3 and the boom. An operator can release the connection between the telescopic cylinder 3 and the boom by operating the manual cylinder pin operating mechanism using a tool inserted through the emergency cylinder pin operating hole 143b.

[0128] In this embodiment, the cylinder pin emergency operation hole 143b and the boom pin emergency operation holes 143c, 143d are provided on the same surface of the boom, so the operator can manually release the connection between the telescopic cylinder 3 and the boom and the booms themselves from the same direction (i.e., the direction indicated by arrow A3 in Fig. 3). This configuration contributes to improving the operability of manual operation.

[0129] <Actions and Effects of This Embodiment> In the case of the mobile crane 1 of this embodiment having the above-mentioned configuration, as mentioned above, even if a problem occurs with the motor, the boom connecting pin 15a can be manually transitioned from the engaged state to the disengaged state, so that the connection between adjacent booms can be manually released.

[0130] Furthermore, in this embodiment, the manual operation member 153 is disposed coaxially with the pin body 150. Therefore, when the manual operation member 153 is manually operated, a force that would tilt the pin body 150 is unlikely to act on the pin body 150. As a result, tilting of the pin body 150 can be suppressed, so the operating force required during manual operation can be reduced and the axial movement of the pin body 150 can be stabilized.

[0131] <Additional Notes> The technical ideas disclosed in the specification and drawings include inventions obtained by arbitrarily combining the various configurations described in the above embodiments. In particular, the technical ideas disclosed in the specification and drawings include inventions obtained by arbitrarily applying the various configurations disclosed in the specification and drawings to the above basic configuration.

[0132] The disclosures of the specification, drawings, and abstract contained in Japanese Patent Application No. 2022-98298, filed on June 17, 2022, are incorporated herein by reference in their entirety. [Industrial Applicability]

[0133] The present invention is not limited to mobile cranes, but can be applied to various work machines (for example, aerial work platforms) equipped with telescopic booms. [Explanation of symbols]

[0134] 1. Mobile crane 10 Running body 12 Swivel table 14 Telescopic Boom 141 Tip boom 141a Cylinder pin receiving part 141b Boom pin holder 142 Intermediate boom 142a Cylinder pin receiving part 142b First boom pin holder 142c Second boom pin holder 142d Third boom pin holder 142e Emergency operation hole for cylinder pin 143 Base boom 143a, 143b Emergency operation hole for cylinder pin 143c, 143d Emergency operation hole for boom pin 144 Support member 144a Boss section 144b Support side screw hole 144c Fasteners 15a, 15b Boom connecting pin 150-pin body 150a First storage section 150b Second storage section 150c divider 150d Pin side through hole 150e, 150f slit 150g recess 151 First coil spring 152 Second coil spring 153 Manual operating member 153a Bolt 153b Nut 153c head 153d Screw shaft 154 Locking claw 16 Wire Rope 17 Hook 2 Actuators 3 Telescopic cylinder 31 Rod member 32 Cylinder parts 4 Pin moving mechanism 40 Trunnion 401 Support hole 41 Electric motor 42 Brake mechanism 43 Transmission Mechanism 431 Reducer 432 Transmission shaft 44 Location information detection device 45 Cylinder connection mechanism 450 Switchgear 451 First Transmission Mechanism 454A, 454B Cylinder connecting pin 455 First biasing mechanism 46 Boom connection mechanism 461 Second Transmission Mechanism 5 Manual operation tools

Claims

1. A plurality of booms that are extended and retracted by the power of actuators; a boom connecting pin that is supported by the boom, moves in a retracting direction by a spring to enter an retracted state in which adjacent booms are connected, and moves in a retracting direction by power of a motor to enter an unretracted state in which the connection is released; a manual operation member that is inserted through the boom connecting pin and is arranged coaxially with the boom connecting pin; a support member having a support-side screw hole and supporting the boom connecting pin on the boom, the manual operation member is threadedly engaged with the support-side screw hole and is configured to be able to convert its own rotation into movement in the removal direction based on the threaded engagement, When the manual operation member is rotated based on manual operation by an operator, the boom connecting pin moves in the removal direction together with the manual operation member, thereby releasing the connection between the adjacent booms. Work equipment.

2. A plurality of booms that are extended and retracted by the power of actuators; a boom connecting pin that is supported by the boom, moves in a retracting direction by a spring to enter an retracted state in which adjacent booms are connected, and moves in a retracting direction by power of a motor to enter an unretracted state in which the connection is released; a manual operation member that is inserted through the boom connecting pin and is arranged coaxially with the boom connecting pin; a boom connection mechanism that switches the boom connecting pin between the engaged state and the disengaged state, the boom connecting pin is configured by a pair of pins that are moved synchronously with each other by the boom connecting mechanism, When one of the pair of pins is manually operated in a state in which the pair of pins are engaged with the boom connecting mechanism, the pair of pins simultaneously move in the extraction direction, When the manual operation member is rotated based on manual operation by an operator, the pair of pins move in the removal direction together with the manual operation member, and the connection between the adjacent booms is released. Work equipment.

3. A plurality of booms that are extended and retracted by the power of actuators; a boom connecting pin that is supported by the boom, moves in a retracting direction by a spring to enter an retracted state in which adjacent booms are connected, and moves in a retracting direction by power of a motor to enter an unretracted state in which the connection is released; a manual operation member that is inserted through the boom connecting pin and is arranged coaxially with the boom connecting pin, the manual operation member is rotatable and is always assembled to the boom connecting pin, When the manual operation member is rotated based on manual operation by an operator, the boom connecting pin moves in the removal direction together with the manual operation member, thereby releasing the connection between the adjacent booms. Work equipment.

4. 2. The work machine according to claim 1, wherein the spring is disposed between the support member and the boom connecting pin, and constantly biases the boom connecting pin in the inserting direction.

5. 5. The work machine according to claim 4, wherein the support member has a boss portion in which the support-side screw hole is formed, which positions the spring, and which can accommodate a nut provided at the tip of the manual operation member inside.

6. The boom connecting pin has a pair of slits at a base end portion, The support member is inserted through the slit, The work machine according to claim 1 , wherein movement of the boom connecting pin is guided based on engagement between the slit and the support member.

7. The work machine according to claim 6, wherein the boom connecting pin is configured to be movable in the removal direction up to a position where the slit and the support member abut against each other in the axial direction of the boom connecting pin.

8. The pair of slits are provided at an upper end and a lower end of the boom connecting pin, The work machine according to claim 6, wherein the support member is fixed to the boom at an upper end and a lower end thereof via fastening parts, and is inserted through the pair of slits from above and below.

9. The work machine according to claim 1 , wherein the manual operation member has a pressing portion that presses the boom connecting pin in the removal direction.

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