JP7393317B2 - Construction machine attachment/detachment device and construction machine equipped with the same - Google Patents

Description

The present invention relates to a construction machine attachment attachment/detachment device for attaching/detaching a working attachment of a construction machine to/from an arm of a working device, and a construction machine equipped with the same.

2. Description of the Related Art Conventionally, for example, an excavating machine, which is a type of construction machine, has a structure in which a working attachment is removably attached to an arm constituting the excavating apparatus as a front working device. As attachments, buckets for excavation work, crushing devices (breakers) for crushing work, etc. can be replaced depending on the content of the work. The attachment is connected to the arm via an attachment attachment/detachment device provided on the distal end side of the arm, and is attached/detached to/from the arm by the attachment attachment/detachment device.

The attachment attachment/detachment device includes a fixed hook and a movable hook provided on a predetermined frame, and each hook is connected to the attachment by engaging with a support pin that the attachment has as an engaged part. There is something. In such a configuration, a configuration is known in which a hydraulic cylinder is provided as an actuator for moving the movable hook, and the attachment/detachment operation is performed by expanding and contracting the hydraulic cylinder (see, for example, Patent Document 1 and Patent Document 2). . Further, as disclosed in Patent Document 2, some attachment attachment/detachment devices have a locking portion for preventing a support pin of an attachment from falling off a fixing hook.

Japanese Patent Application Publication No. 2004-60371 Japanese Patent Application Publication No. 2016-166508

According to the conventional attachment attachment/detachment device as described above, there is a problem in that the attachment may be detached if the supply of power to the hydraulic cylinder is cut off due to damage to the hydraulic equipment or the like. In this regard, it is believed that the configuration having a lock portion as disclosed in Patent Document 2 can prevent the support pin from falling off from the fixed hook, thereby suppressing the detachment of the attachment. It will be done.

However, since the attachment is connected to the arm side by engaging each of the fixed hook and movable hook with the support pin of the attachment, the lock part only prevents the support pin from falling off from the fixed hook. However, this is insufficient as a countermeasure against detachment of the attachment. As described above, in the conventional attachment attachment/detachment device, there is room for improvement in order to prevent the attachment from coming off and increase safety.

The present invention has been made in view of the above-mentioned problems, and even when the power supply to the actuator is cut off, the connected state of the attachment can be maintained, thereby achieving high safety. An object of the present invention is to provide an attachment attachment/detachment device for a construction machine and a construction machine equipped with the same.

An attachment attachment/detachment device for a construction machine according to the present invention is an attachment/detachment device for a construction machine that attaches/detaches a work attachment to/from an arm of a work device, and includes a main body frame connected to the arm, and a body frame connected to the arm of the work device. a first hook that is rotatably provided and engages with a first engaged portion of the attachment; and a first hook that is provided on the main body frame and engages a second engaged portion of the attachment. a first actuator that rotates the first hook with respect to the main body frame; and a first actuator that is rotatably provided on the first hook and that is engaged with the first hook. A retaining member that restricts separation of the engaging portion from the first hook; and a second actuator that is provided on the first hook and connected to the retaining member and rotates the retaining member. , the second actuator is a movable part that operates upon receiving power and rotates the retaining member in a direction opposite to a direction in which the retaining member is in a lock position that restricts the detachment of the first engaged part; and a biasing member that biases the movable portion in a rotational direction in which the retaining member reaches the lock position.

In addition, in the attachment mounting/detaching device for a construction machine according to another aspect of the present invention, the attachment mounting/detaching device for a construction machine is provided such that the attachment/detachable device is rotatably provided on the main body frame, and the second hook is engaged with the second hook. a second retaining member that restricts detachment of the second engaged portion from the second hook; and a locking position of the second retaining member that restricts detachment of the second engaged portion. a second biasing member that biases in a rotational direction; and a first hook that is rotatably provided on the main frame side and rotates in a direction to release the engagement with the first engaged portion. The device further includes a rotation operation member that rotates in response to a pressing action to rotate the second retaining member in a direction opposite to the direction in which the locking position is reached.

Furthermore, in the attachment mounting/detaching device for construction machinery according to another aspect of the present invention, in the attachment mounting/detaching device for construction machinery, the rotation operation member has a contact portion that is brought into contact with the first hook; It has an arm portion that engages with the second retaining member.

Further, in the attachment mounting/detaching device for construction machinery according to another aspect of the present invention, in the attachment mounting/detaching device for construction machinery, the main body frame has a pair of left and right wall portions, and the first actuator is configured to The second actuator is disposed between the first actuator and one of the left and right wall sections.

The construction machine according to the present invention provides a front working device including an attachment attachment/detachment device of the construction machine, a traveling device, and the arm that is provided on the front side of the traveling device and supports the attachment in a detachable manner by the attachment attachment/detachment device. It is equipped with the following.

According to the present invention, even if the supply of power to the actuator is cut off, the connected state of the attachment can be maintained, and high safety can be achieved.

FIG. 1 is a left side view of an excavating machine according to an embodiment of the present invention. It is a left side view showing a part of excavation equipment concerning one embodiment of the present invention. FIG. 2 is a perspective view showing a detached state of an attachment attaching/detaching device and a bucket according to an embodiment of the present invention. FIG. 2 is a left side view of an attachment attachment/detachment device according to an embodiment of the present invention. FIG. 2 is a left side view with a partially omitted configuration of an attachment attachment/detachment device according to an embodiment of the present invention. FIG. 2 is a right side view with a partially omitted configuration of an attachment attachment/detachment device according to an embodiment of the present invention. FIG. 1 is a front and upper perspective view of an attachment attachment/detachment device according to an embodiment of the present invention. FIG. 1 is a plan view of an attachment attachment/detachment device according to an embodiment of the present invention. FIG. 1 is a front-down perspective view of an attachment attachment/detachment device according to an embodiment of the present invention. FIG. 2 is a rear upper perspective view of an attachment attachment/detachment device according to an embodiment of the present invention. 1 is a circuit diagram showing a hydraulic circuit configuration of an attachment attachment/detachment device according to an embodiment of the present invention. FIG. 2 is a perspective view showing the configuration of a rear locking member, a rotating arm body, etc. of an attachment attachment/detachment device according to an embodiment of the present invention. FIG. 3 is an explanatory diagram of the operation of the attachment attachment/detachment device according to an embodiment of the present invention when attaching a bucket. FIG. 2 is an explanatory diagram of the operation of the attachment attachment/detachment device according to an embodiment of the present invention when a bucket is removed.

The present invention relates to an attachment attachment device for attaching and detaching a work attachment to and from an arm in a front working machine of construction machinery, and improves safety by devising a configuration for operating a hook on the movable side. This is what we are trying to achieve. Embodiments of the present invention will be described below with reference to the drawings.

In this embodiment, a construction machine according to the present invention will be explained by taking an excavating machine, which is a swinging work vehicle, as an example. However, the construction machine according to the present invention is not limited to excavation work machines, but can be widely applied to other construction machines such as crane work machines and wheel loaders.

First, the overall configuration of an excavating machine 1 according to the present embodiment will be described using FIG. 1. As shown in FIG. 1, the excavating work machine 1 includes a traveling device 2 as a self-propelled traveling vehicle body, and an excavating device 3 and an earth removal device 4 as working parts attached to the traveling device 2.

The traveling device 2 is a part of the main body of the excavating machine 1, and includes a pair of left and right crawler-type traveling sections 5, 5, and a body frame serving as a base interposed between the left and right traveling sections 5, 5. 6 and a swivel base 7 provided on the body frame 6. The swivel base 7 is configured to have a substantially circular shape in plan view, and is provided so as to be swivelable in either left or right direction around an axis in the vertical direction by a swivel support portion 6a provided on the body frame 6.

A driving section 8 is provided on the swivel base 7. Further, in the rear half of the swivel base 7, a prime mover section 9 is provided, in which an engine and the like are covered with a bonnet or the like.

The driving unit 8 is for driving and operating the traveling device 2 , the excavating device 3 , and the earth removal device 4 , and is provided in a cabin 10 provided on the swivel base 7 . The cabin 10 has a frame forming its outer shape and a plurality of windows made of a transparent member such as glass, and is generally box-shaped as a whole.

In the driver section 8, a driver's seat support is provided on the floor, and a driver's seat 8a is provided on the driver's seat support. The driving unit 8 is provided with, for example, a pair of left and right travel levers extending upward from the floor, a work operation pedal disposed on the floor, and the like. In addition, in the operation section 8, around the driver's seat 8a, there is a work operation lever for operating the work section (the excavation device 3 or the earth removal device 4) and an operation panel section having various operation sections such as switches. It is provided.

A base end portion of the excavation device 3 is attached to the left and right center portions of the front end of the swivel table 7. Furthermore, an earth removal device 4 is attached to the front side of the body frame 6. The earth removal device 4 includes a support frame 4a extending in the front-rear direction between the left and right running parts 5, 5, and a blade 4b as an earth removal plate provided at the tip side of the support frame 4a. The earth removal device 4 is provided so as to be rotatable up and down by a cylinder mechanism provided between the support frame 4a and the body frame 6.

In the excavating work machine 1 having the above configuration, desired operations and work are performed by appropriately operating the travel lever, work operation lever, etc. by an operator seated in the driver's seat 8a. Specifically, for example, by operating a travel lever, the traveling device 2 is caused to travel straight forward and backward or turn left and right. Further, by operating the work operation lever, excavation work by the excavation device 3, earth removal work or land leveling work by the earth removal device 4 is performed.

The excavation device 3 will be explained using FIGS. 1 to 3. The excavation device 3 is a front working device provided on the front side of the traveling device 2. A support bracket 15 is provided to protrude forward at the left and right center portions of the front end of the swivel base 7, and a base end portion of the excavation device 3 is attached to the support bracket 15. The excavation device 3 has a boom support bracket 16 as a member constituting its base end. In the excavation device 3, the boom support bracket 16 is rotatably supported with respect to the support bracket 15 on the machine side, with the vertical direction being the rotation axis direction.

The excavator 3 is provided so as to swing left and right with respect to the swivel base 7 by a swing cylinder (not shown) disposed on the right side of the boom support bracket 16 . The swing cylinder is provided between the boom support bracket 16 and the swivel base 7.

The excavation device 3 includes a boom 17 constituting a base portion thereof, an arm 18 connected to the distal end of the boom 17, and a bucket 20 attached to the distal end of the arm 18. The excavation device 3 includes a boom cylinder 21 that rotates the boom 17, an arm cylinder 22 that rotates the arm 18, and a work tool cylinder 23 that rotates the bucket 20.

The boom 17 has a boomerang-shaped bent shape when viewed from the side. A base end portion of the boom 17 is rotatably supported by the boom support bracket 16 with the left-right direction being a rotation axis direction. The boom cylinder 21 is disposed on the front side of the boom 17 in an upright state, and is installed between the boom support bracket 16 and a bracket 17a that projects inside the bent portion of the boom 17. As the boom cylinder 21 expands and contracts, the boom 17 rotates relative to the boom support bracket 16.

A base end of an arm 18 is rotatably connected to the distal end of the boom 17 with the left-right direction as a rotation axis direction. The arm cylinder 22 is disposed on the upper side (back side) of the boom 17 in an upright state, and includes a bracket 17b protruding from the outside of the bent portion of the boom 17, and a rear bracket protruding from the rear end of the arm 18. 18a and the rear end of the terminal 18a. As the arm cylinder 22 expands and contracts, the arm 18 rotates relative to the boom 17.

The bucket 20 is connected to the tip of the arm 18 via an attachment attachment/detachment device 30. That is, the attachment attachment/detachment device 30 is connected to the tip of the arm 18 and is detachably connected to the bucket 20.

The work tool cylinder 23 is arranged on the front side (back side) of the arm 18 that hangs down from the upper end of the boom 17. The work tool cylinder 23 includes a cylinder 23a and a cylinder rod 23b which has a piston at one end and is slidably provided within the cylinder 23a via the piston. One end of the work tool cylinder 23, which is the bottom side (cylinder 23a side), is rotatably supported by the front bracket 18b with the left-right direction as the rotation axis direction. The front bracket 18b is provided at the rear end of the arm 18 so as to protrude from the front side of the rear bracket 18a.

On the other hand, the other end of the work tool cylinder 23, that is, the end on the rod side (cylinder rod 23b side) is connected to the attachment attachment/detachment device 30 via the first link 26. Further, the rod-side end of the work tool cylinder 23 is supported via a second link 27 to a portion near the tip of the arm 18 .

The second link 27 includes a pair of left and right link arms 27a, a base side support shaft 27b installed between one end of the pair of link arms 27a, and a tip end side installed between the other end of the pair of link arms 27a. It has a support shaft 27c. The second link 27 is rotatably supported with respect to the arm 18 by a base side support shaft 27b.

The link arm 27a is constituted by an arm-shaped (longitudinal) plate member whose thickness direction is the left-right direction. The pair of link arms 27a have one end located on the left and right outer sides of the left and right side surfaces 18c of the arm 18, and are connected to the arm 18 by a base side support shaft 27b that passes through the vicinity of the tip of the arm 18 in the left and right direction. Rotatably supported.

The distal end portion of the cylinder rod 23b of the working tool cylinder 23 is rotatably supported by the distal end support shaft 27c. A boss portion 23c is provided at the distal end of the cylinder rod 23b, through which the distal end support shaft 27c passes. Further, one end side (rear end side) of the first link 26 is rotatably supported by the tip side support shaft 27c. One end portion of the first link 26 branches left and right, and a boss portion 26a is provided at each of the left and right ends to allow the distal end support shaft 27c to pass therethrough. On the tip side support shaft 27c, the boss portion 23c of the cylinder rod 23b is located between the left and right boss portions 26a of the first link 26.

The other end side (front end side) of the first link 26 is connected to the attachment attachment/detachment device 30 by a link support shaft 28 which is a first support shaft provided at a predetermined portion of the attachment attachment/detachment device 30 with the left-right direction as the axial direction. are rotatably connected. The tip of the arm 18 is connected to the attachment attachment/detachment device 30 by an arm support shaft 29 which is a second support shaft provided at a different location from the link support shaft 28 in the attachment attachment/detachment device 30 with the axial direction extending in the left-right direction. is rotatably connected to.

In such a configuration, the extension and contraction of the work tool cylinder 23 causes the first link 26 and the second link 27 to rotate, and the attachment attachment/detachment device 30 rotates about the arm support shaft 29 as a rotation axis. . Accordingly, the bucket 20 rotates integrally with the attachment attachment/detachment device 30.

In the excavation device 3 having the above configuration, the bucket 20 is detachably attached to the arm 18 as an attachment for work by an attachment attachment/detachment device 30. Depending on the content of work performed by the excavating machine 1, other devices such as a grapple or a breaker may be attached as work attachments instead of the bucket 20. As described above, the excavation equipment 3 includes an arm 18 that removably supports a work attachment by an attachment attachment/detachment device 30. Attachments are fitted according to the requirements.

The configuration of the attachment attachment/detachment device 30 will be explained using FIGS. 2 to 12. In addition, in the following description, in the attachment attachment/detachment device 30, the left side and the right side in FIG. 4 are respectively referred to as the front and the rear, and the upper and lower sides in FIG. 4 are respectively referred to as the upper and lower sides.

The attachment attachment/detachment device 30 is a device for attaching/detaching the bucket 20 of the excavating machine 1 to/from the arm 18 of the excavating device 3 . The attachment attachment/detachment device 30 includes a main body frame 31, a movable hook 33 as a first hook, and a fixed hook 34 as a second hook. The attachment attachment/detachment device 30 is configured to be substantially symmetrical as a whole.

As shown in FIG. 3, the attachment attachment/detachment device 30 includes a movable hook 33 and a fixed hook 34, which are a front support pin 35 which is a first engaged part and a second engaged part which the bucket 20 has, respectively. It is connected to the bucket 20 by engaging with the rear support pin 36.

The front support pin 35 and the rear support pin 36 are straight rod-shaped members whose axial direction is in the left-right direction, and are a pair of left and right supports protruding from the back surface 20a of the bucket 20 at a predetermined interval in the left-right direction. It is constructed between the rib portions 37. The support rib portion 37 is a plate-shaped projecting portion whose thickness direction is the left-right direction.

The left and right support rib portions 37 support the front support pin 35 and the rear support pin 36 at positions spaced apart from each other by a predetermined distance. The left and right support rib portions 37 pass through both ends of the front support pin 35 and the rear support pin 36, and support these support pins in a fixed state. The left and right support rib portions 37 are provided on the base side (upper side in FIG. 2) of the back surface portion 20a of the bucket 20. Note that a plurality of claw portions 20b are provided at the tip of the back surface portion 20a of the bucket 20 at predetermined intervals in the left-right direction (see FIG. 2).

The main body frame 31 is a frame portion of the attachment attachment/detachment device 30 that is connected to the arm 18 of the excavation device 3 . The main body frame 31 has a pair of left and right main frame bodies 41. The main frame body 41 has a main body plate portion 41a forming the base thereof, and inner protrusions 41b provided on the left and right inner sides of the main body frame body 41.

The main body plate portion 41a is a plate-shaped portion whose thickness direction is in the left-right direction, and in side view, has an approximately inverted trapezoidal outer shape with a concave upper side and a tapered shape from the rear side to the front side. . The inner protrusion portion 41b is provided so as to protrude from the left and right inner surfaces of the main body frame body 41 with a substantially constant protrusion dimension. The inner protrusion 41b has its longitudinal direction in the front-rear direction and is provided along the lower rear side of the main body plate 41a. The main body plate portion 41a and the inner protrusion portion 41b constitute an integrated main body frame body 41.

The main frame 31, which is mainly composed of a pair of left and right main frame bodies 41, is rotatably supported with respect to the arm 18 by an arm support shaft 29. The arm support shaft 29 is rotatably supported at the distal end of the arm 18 so as to pass through the arm 18 in the left-right direction. The arm support shaft 29 has left and right ends protruding to both the left and right sides at the tip of the arm 18 .

A rear shaft support hole 41c is formed in the rear upper part of the main frame body 41 to receive and support the left and right ends of the arm support shaft 29. The left and right main frame bodies 41 are connected to the arm support shaft 29 so as not to be relatively rotatable, and rotate integrally with the arm support shaft 29 with respect to the arm 18 . In the main frame body 41 on the right side, cylindrical boss portions 41d are provided on the left and right outer sides of the rear shaft support hole 41c, and a connecting bolt 42 that passes through the boss portion 41d and the arm support shaft 29 in the radial direction. The main frame body 41 and the arm support shaft 29 are connected by nuts 42a and the like.

Further, the main body frame 31 is rotatably supported with respect to the first link 26 by a link support shaft 28 . As shown in FIG. 3, the link support shaft 28 is rotatably supported while passing through a boss portion 26b provided at the other end of the first link 26 in the left-right direction. The link support shaft 28 has left and right end portions protruding from the other end portion of the first link 26 to both the left and right sides.

A front shaft support hole 41e is formed in the front upper part of the main frame body 41 to receive and support the left and right ends of the link support shaft 28. The left and right main frame bodies 41 are connected to the link support shaft 28 so as not to be relatively rotatable, and rotate integrally with the link support shaft 28 with respect to the first link 26 . In the main frame body 41 on the right side, cylindrical boss portions 41f are provided on the left and right outer sides of the front shaft support hole 41e, and a connecting bolt 43 that passes through the boss portion 41f and the link support shaft 28 in the radial direction is provided. The main body frame body 41 and the link support shaft 28 are connected by nuts 43a and the like.

The movable hook 33 is a portion that is rotatably provided on the main body frame 31 and engages with a front support pin 35 that the bucket 20 has. The movable hook 33 includes a pair of left and right mounting frame sections 45, a hook section 46 provided for each mounting frame section 45, and a hook support shaft 47 installed between the left and right hook sections 46.

The mounting frame portion 45 is a plate-shaped portion whose thickness direction is the left-right direction, and has a substantially triangular outer shape when viewed from the side, and has a shape that tapers from the bottom to the top. The mounting frame portion 45 is located on the left and right inner sides of the main body frame body 41, and when viewed from the side, the upper end portion along the circumferential shape overlaps the formation area of the front shaft support hole 41e on the front side of the main body plate portion 41a. ing.

The hook portion 46 is provided as a portion having a predetermined thickness in the left-right direction on the left and right inner sides of the mounting frame portion 45. The hook portion 46 is provided integrally with the mounting frame portion 45 by fixing the members forming the mounting frame portion 45 and the hook portion 46 to each other by welding or the like. The hook portion 46 includes an arm portion 46a having a substantially rectangular shape when viewed from the side, and a hook extending in a curved shape from one end side (rear end side) of the arm portion 46a to form a hook shape together with the arm portion 46a when viewed from the side. It has a stop part 46b.

In the hook portion 46, the rear end portion of the arm portion 46a and the locking portion 46b form an engagement surface 46c having a concave shape with the front side open when viewed from the side. In the hook portion 46, the engagement surface 46c becomes a portion that receives contact with the front support pin 35 of the bucket 20. The hook portion 46 overlaps the front upper portion of the arm portion 46a with the mounting frame portion 45 in a side view.

The hook support shaft 47 is constituted by a cylindrical member whose axial direction is the left-right direction, and both ends thereof are inserted into the left and right hook portions 46 . For this reason, a shaft support hole 46d into which the hook support shaft 47 is inserted is formed in the upper front portion of the arm portion 46a of the hook portion 46. The shaft support hole 46d is formed in a portion of the hook portion 46 that overlaps the mounting frame portion 45 in a side view.

The hook support shaft 47 is fixed to the hook portion 46 by bolts 47a or the like that are threaded along the radial direction of the hook support shaft 47, so that the hook support shaft 47 is supported so as not to rotate relative to the hook portion 46. That is, the pair of left and right mounting frame sections 45, hook sections 46, and hook support shaft 47 constitute the movable hook 33 as an integral rotating body.

Furthermore, in the movable hook 33, a substantially rectangular plate-shaped construction plate 48 is installed between the front edges of the left and right mounting frame parts 45 in a state fixed to each mounting frame part 45 by welding or the like (Fig. (See 3). Further, between the left and right hook parts 46, a hook connecting part 49, which is a part that connects the left and right hook parts 46, is installed as an integral part with the hook part 46. The hook connecting portion 49 has a curved surface portion 49a on the front side that follows the curved shape of the engagement surface 51c of the hook portion 51 when viewed from the side. The hook connecting portion 49 is provided so as to fit within the outer shape of the hook portion 46 when viewed from the side.

The movable hook 33 is rotatably supported by the link support shaft 28 with respect to the main body frame 31. Therefore, the movable hook 33 has a shaft support hole 33a at the upper end of the mounting frame portion 45 through which the link support shaft 28 passes. In this way, the movable hook 33 is moved in the left and right direction by the link support shaft 28 fixedly provided to the main body frame 31 between the front parts of the left and right main frame bodies 41 of the main body frame 31. It is rotatably supported.

The fixing hook 34 is a portion that is provided on the main body frame 31 and engages with a rear support pin 36 that the bucket 20 has. The fixed hook 34 is provided in a fixed state with respect to the main body frame 31, and is an integral part that rotates with respect to the arm 18 together with the main body frame 31 and the arm support shaft 29 provided in a fixed state with the main body frame 31. It constitutes a rotating body. The fixed hook 34 has a pair of left and right hook parts 51 and a construction part 52 provided between the left and right hook parts 51.

The hook portion 51 is provided as a portion having a predetermined thickness in the left-right direction on the left and right inner sides of the inner protrusion portion 41b of the main frame body 41. The hook portion 51 is provided integrally with the inner protrusion 41b (main frame body 41) by fixing the members forming the inner protrusion 41b and the hook portion 51 to each other by welding or the like.

The hook portion 51 has a shape that is substantially symmetrical in the front-rear direction when viewed from the side with respect to the hook portion 46 of the movable hook 33. The hook portion 51 includes an arm portion 51a having a substantially rectangular shape when viewed from the side, and a locking member extending in a curved shape from one end side (front end side) of the arm portion 51a to form a hook shape together with the arm portion 51a when viewed from the side. 51b.

In the hook portion 51, the front end portion of the arm portion 51a and the locking portion 51b form an engagement surface 51c having a concave shape with the rear side open when viewed from the side. In the hook portion 51, the engagement surface 51c becomes a portion that receives contact with the rear support pin 36 of the bucket 20. In side view, the hook portion 51 overlaps the upper edge of the arm portion 51a with the inner protrusion portion 41b.

The construction portion 52 is a portion that connects the left and right hook portions 51 to each other. The construction portion 52 has a curved surface portion 52a on the rear side that follows the curved shape of the engagement surface 51c of the hook portion 51 when viewed from the side. The construction portion 52 is provided so as to fit within the outer shape of the hook portion 51 when viewed from the side.

The attachment attachment/detachment device 30 also includes a first hydraulic cylinder 55 as a first actuator, a front locking member 56 as a retaining member (first retaining member), and a second hydraulic cylinder 57 as a second actuator. Be prepared.

The first hydraulic cylinder 55 is an actuator that rotates the movable hook 33 with respect to the main body frame 31. The first hydraulic cylinder 55 rotates the movable hook 33 back and forth around the link support shaft 28 by expanding and contracting.

The first hydraulic cylinder 55 is provided in the center of the attachment attachment/detachment device 30 in the left-right direction, with the expansion/contraction direction being the front-rear direction in plan view. The first hydraulic cylinder 55 has a cylinder tube 61 and a piston rod 62 that is slidably provided with respect to the cylinder tube 61, and expands and contracts by the sliding movement of the piston rod 62 with respect to the cylinder tube 61. A piston 63 that slides within the cylinder tube 61 is provided at one end of the piston rod 62 located within the cylinder tube 61 (see FIG. 11).

As shown in FIG. 11, the internal space of the cylinder tube 61 is divided by the piston 63 into a bottom side chamber 61a, which is a space on the cylinder tube 61 side (bottom side), and a rod side chamber, which is a space on the piston rod 62 side (rod side). It is divided into 61b and 61b. The first hydraulic cylinder 55 expands and contracts by moving the piston rod 62 relative to the cylinder tube 61 by supplying and discharging pressure oil to and from the bottom side chamber 61a and the rod side chamber 61b, respectively.

Specifically, as shown in FIG. 11, one end side of a bottom hydraulic piping 65 formed of a hose or the like is connected to the first hydraulic cylinder 55 so as to communicate with the bottom chamber 61a. The other end of the bottom hydraulic piping 65 is connected to a bottom cylinder port (A) of an electromagnetic switching valve 67 for switching the flow path. The bottom side hydraulic piping 65 is provided with a check valve 65a.

Further, one end side of a rod-side hydraulic pipe 66 constituted by a hose or the like is connected to the first hydraulic cylinder 55 so as to communicate with the rod-side chamber 61b. The other end of the rod-side hydraulic piping 66 is connected to a rod-side cylinder port (B) of an electromagnetic switching valve 67 . Note that a connection block 61c is provided above the cylinder tube 61 to receive connection of the bottom side hydraulic piping 65 and the rod side hydraulic piping 66 (see FIG. 10, etc.).

One end of a supply pipe 68 is connected to the supply port (P) of the electromagnetic switching valve 67 . The other end side of the supply pipe 68 is open facing an oil tank 69 provided on the traveling device 2 side. A hydraulic pump 64 is provided in the supply pipe 68 , and the operation of the hydraulic pump 64 supplies hydraulic oil in the oil tank 69 to the first hydraulic cylinder 55 via the electromagnetic switching valve 67 . Further, one end side of a discharge pipe 70 which is a return pipe to the oil tank 69 is connected to the discharge port (T) of the electromagnetic switching valve 67 . The other end side of the discharge pipe 70 is open facing the oil tank 69.

The support structure of the first hydraulic cylinder 55 will be explained. The first hydraulic cylinder 55 is provided with the piston rod 62 side facing forward, and has the piston rod 62 side supported by the movable hook 33 and the cylinder tube 61 side supported by the main body frame 31. There is. That is, the movable hook 33 and the main body frame 31 are connected to each other by the first hydraulic cylinder 55.

The front side of the first hydraulic cylinder 55 is rotatably supported with respect to the hook support shaft 47. A substantially cylindrical boss portion 62a having a hole through which the hook support shaft 47 passes is provided at the tip of the piston rod 62. The boss portion 62a is located at the center of the hook support shaft 47 in the axial direction, and is supported so as to be rotatable relative to the hook support shaft 47.

On the other hand, the rear side of the first hydraulic cylinder 55 is rotatably supported with respect to the main body frame 31 by a cylinder support shaft 71 that protrudes from the rear part of the cylinder tube 61 to both left and right sides. There is. The left and right cylinder support shafts 71 are supported while being inserted into support holes 41g provided in the front portions of the left and right inner protrusions 41b, respectively.

The cylinder support shaft 71 is fixed to the inner protrusion 41b by bolts 71a or the like that are screwed along the radial direction of the cylinder support shaft 71, so that the cylinder support shaft 71 is supported so as not to rotate relative to the main body frame 41. The cylinder tube 61 is supported relative to the cylinder support shaft 71 so as to be relatively rotatable.

According to the support structure of the first hydraulic cylinder 55 as described above, the first hydraulic cylinder 55 expands and contracts, and as a result, the first hydraulic cylinder 55 rotates by the cylinder support shaft 71 and moves relative to the cylinder tube 61. The hook support shaft 47 moves together with the piston rod 62 (see arrow A1 in FIG. 5). As a result, the movable hook 33 including the hook support shaft 47 rotates around the axis of the link support shaft 28 with respect to the main body frame 31 (see arrow A2 in FIG. 5).

The front locking member 56 is a member that is rotatably provided on the movable hook 33 and restricts separation of the front support pin 35 from the movable hook 33 when engaged by the movable hook 33 . The front locking member 56 is rotatably supported by a hook support shaft 47 that constitutes the movable hook 33. The front locking member 56 includes a pair of left and right lock plate portions 73 and a construction plate portion 74 that connects the left and right lock plate portions 73 to each other.

The lock plate portion 73 has a shape in which a lock piece portion 73b protrudes in a predetermined direction from a substantially disk-shaped base portion 73a that is a portion supported by the hook support shaft 47. The lock piece portion 73b protrudes in a substantially tangential direction with respect to the substantially disk-shaped base portion 73a when viewed from the side, and has a substantially rectangular distal end.

In the lock plate part 73, the lock piece part 73b protrudes toward the rear side from the lower part of the base part 73a. The direction in which the lock piece portion 73b protrudes from the base portion 73a is toward the engagement surface 46c of the hook portion 46 when viewed from the side.

The lock plate part 73 has a hole part 73c in the base part 73a, through which the hook support shaft 47 passes. The left and right lock plate portions 73 are provided on the hook support shaft 47 at positions adjacent to the boss portion 62a of the piston rod 62 of the first hydraulic cylinder 55 on both left and right sides. In this embodiment, of the left and right lock plate parts 73, the right lock plate part 73R has a thickness greater than that of the left lock plate part 73.

The construction plate portion 74 is a rectangular plate-shaped portion, and is constructed between the portions of the left and right lock plate portions 73 on the lock piece portion 73b side while being fixed to each lock plate portion 73 by welding or the like. (See Figure 9). The left and right lock plate portions 73 and the construction plate portion 74 configure the front lock member 56 as an integral rotating body that rotates with respect to the hook support shaft 47.

The front lock member 56 rotates about the hook support shaft 47 at a rotation position in which the lock pieces 73b of the left and right lock plate parts 73 protrude downward from the arm part 46a of the movable hook 33 when viewed from the side. , the lock position is set to prevent the front support pin 35 engaged with the movable hook 33 from disengaging from the movable hook 33 (see FIG. 13C). That is, the front locking member 56 rotates in a range from an unlocked position hidden within the outer shape of the arm portion 46a in a side view to a locked position, as shown in FIG. 5 and the like. The front locking member 56 changes from the unlocked position to the locked position by rotating clockwise (clockwise) when viewed from the left side shown in FIG. 5 .

The second hydraulic cylinder 57 is an actuator that is provided on the movable hook 33 and connected to the front locking member 56 to rotate the front locking member 56 . The second hydraulic cylinder 57 rotates the front locking member 56 around the hook support shaft 47 by expanding and contracting.

The second hydraulic cylinder 57 is a hydraulic cylinder that is smaller than the first hydraulic cylinder 55, and is provided with the direction of expansion and contraction as the front-rear direction in plan view. The second hydraulic cylinder 57 has a cylinder tube 76 and a piston rod 77 slidably provided with respect to the cylinder tube 76, and expands and contracts by the sliding movement of the piston rod 77 with respect to the cylinder tube 76. A piston 78 that slides within the cylinder tube 76 is provided at one end of the piston rod 77 located within the cylinder tube 76 (see FIG. 11).

As shown in FIG. 11, the internal space of the cylinder tube 76 is divided into a bottom side chamber 76a, which is a space on the cylinder tube 76 side (bottom side), and a rod side chamber, which is a space on the piston rod 77 side (rod side), by the piston 78. It is divided into 76b and 76b. A cylinder inner spring 79 as a biasing member (first biasing member) is provided in the rod side chamber 76b.

The cylinder inner spring 79 is a coil spring, and is provided in the rod side chamber 76b so that the piston rod 77 passes through it, with the direction of expansion and contraction being the direction of expansion and contraction of the second hydraulic cylinder 57. The cylinder inner spring 79 biases the piston rod 77 toward the bottom side (in the retracting direction) via the piston 78 due to its elastic force.

As shown in FIG. 11, one end side of a branch pipe 80 branched from the rod side hydraulic pipe 66 is connected to the second hydraulic cylinder 57 so as to communicate with the bottom side chamber 76a. The cylinder tube 76 is provided with a protruding connection port 76c to which the branch pipe 80 is connected. The branch pipe 80 is formed of a hose or the like, and has the other end connected to the rod-side hydraulic pipe 66 .

In this way, the second hydraulic cylinder 57 is configured as a single-acting cylinder with a spring that retracts the piston rod 77 by the elastic force of the cylinder internal spring 79. That is, when the hydraulic pressure supplied to the bottom side chamber 76a through the branch pipe 80 exceeds a predetermined value, the second hydraulic cylinder 57 causes the piston rod 77 to protrude from the cylinder tube 76 against the biasing force of the cylinder internal spring 79. Stretch. On the other hand, when the oil pressure in the bottom side chamber 76a falls below a predetermined value, the second hydraulic cylinder 57 pulls the piston rod 77 into the cylinder tube 76 by the biasing force of the cylinder inner spring 79, thereby shortening the piston rod 77.

The support structure of the second hydraulic cylinder 57 will be explained. The second hydraulic cylinder 57 is provided with the piston rod 77 side facing forward, and has the piston rod 77 side supported by the front lock member 56 and the cylinder tube 76 side supported by the movable hook 33. ing.

The front side of the second hydraulic cylinder 57 is rotatably supported by a piston rod support shaft 81 whose axial direction is in the left-right direction with respect to the right lock plate portion 73R that constitutes the front lock member 56. The piston rod support shaft 81 is supported by a shaft support protrusion 73d that protrudes upward from the base 73a in the lock plate portion 73R. A cylindrical boss portion 77a having a hole through which the piston rod support shaft 81 passes is provided at the tip of the piston rod 77.

On the other hand, on the rear side of the second hydraulic cylinder 57, at the rear end of the cylinder tube 76, a cylinder tube support shaft 82 whose axial direction is in the left-right direction is attached to the left and right mounting frame portions 45 of the movable hook 33. It is rotatably supported on the rear part of the right mounting frame section 45R. The cylinder tube support shaft 82 projects leftward from the mounting frame portion 45R, passes through the rear end of the cylinder tube 76, and supports the second hydraulic cylinder 57.

According to the support structure of the second hydraulic cylinder 57 as described above, the shaft support protrusion 73d is pushed and pulled as the second hydraulic cylinder 57 expands and contracts (see arrow B1 in FIG. 5). As a result, the front locking member 56 rotates around the hook support shaft 47 (see arrow B2 in FIG. 5).

As described above, the second hydraulic cylinder 57 operates by receiving hydraulic pressure as power, and moves the front locking member 56 to the position (locking position) that restricts the separation of the front support pin 35 from the movable hook 33. A piston rod 77 including a piston 78 is provided as a movable part that rotates in the opposite direction. That is, the second hydraulic cylinder 57 is extended by receiving hydraulic pressure from the branch pipe 80, and moves the front locking member 56 from the locked position to the unlocked position. Further, the second hydraulic cylinder 57 holds the front locking member 56 in the unlocked position by the hydraulic pressure supplied to the bottom side chamber 76a through the branch pipe 80.

The second hydraulic cylinder 57 has an inner cylinder spring 79 that urges the piston rod 77 in the rotational direction that moves the front locking member 56 to the locking position. That is, the second hydraulic cylinder 57 retracts and shortens the piston rod 77 by the biasing force of the cylinder inner spring 79, and moves the front locking member 56 from the non-locking position to the locking position. Further, the second hydraulic cylinder 57 holds the front locking member 56 at the locking position by the biasing force of the cylinder inner spring 79. Here, regarding the rotational direction of the front locking member 56, the locking position is a clockwise direction when viewed from the left side.

The arrangement of the second hydraulic cylinder 57 will be explained. In the attachment attachment/detachment device 30, the main body frame 31 has left and right main frame bodies 41 as a pair of left and right wall portions. Further, the first hydraulic cylinder 55 is provided between the left and right main frame bodies 41. In this embodiment, the first hydraulic cylinder 55 is disposed at the center of the left and right main frame bodies 41 in the left-right direction.

In such a configuration, the second hydraulic cylinder 57 is arranged between the first hydraulic cylinder 55 and one of the left and right main body frame bodies 41 . In this embodiment, the second hydraulic cylinder 57 is arranged between the right main body frame body 41R of the pair of left and right main body frame bodies 41 and the first hydraulic cylinder 55 in the left-right direction.

Specifically, the second hydraulic cylinder 57 is provided between the first hydraulic cylinder 55 and the right mounting frame portion 45R provided on the left and right inner sides (left side) of the main frame body 41R. Further, in the left-right direction, the second hydraulic cylinder 57 is located on the left-right inner side (left side) of the inner protrusion 41b of the right main frame body 41R (see FIG. 8).

The attachment attachment/detachment device 30 also includes, on its rear side, a rear lock member 85 as a second retaining member, a lock spring 86 as a second biasing member, and a rotation arm body 87 as a rotation operation member. Be prepared.

The rear locking member 85 is rotatably provided on the main body frame 31 and is a member that restricts separation of the rear support pin 36 from the fixed hook 34 after being engaged with the fixed hook 34 . The rear locking member 85 is rotatably supported with respect to the main body frame 31 by a rear support shaft 91 installed between the left and right hook portions 51 in the main body frame 31 with the left-right direction as the axial direction.

The rear support shaft 91 has both ends supported by the hook portion 51 at predetermined positions. For this reason, the hook portion 51 is formed with support holes 51d that support both ends of the rear support shaft 91. The rear locking member 85 has a pair of left and right locking claws 92 and a connecting shaft part 93 that connects the left and right locking claws 92 to each other.

The lock claw portion 92 is a portion having a predetermined dimension in the left-right direction, and includes a substantially cylindrical support portion 92a that is supported by the rear support shaft 91, and a lock piece portion provided on the front side of the support portion 92a. 92b.

In the lock claw portion 92, the lock piece portion 92b protrudes forward and downward from the support portion 92a in a side view, and has a tapered shape that protrudes downward at an acute angle. The direction in which the lock claw portion 92 protrudes downward is the direction toward the engaging surface 51c of the hook portion 51 when viewed from the side.

The lock claw portion 92 has a hole 92c in the support portion 92a through which the rear support shaft 91 passes. The left and right lock claw portions 92 are located on both left and right ends of the rear support shaft 91, and are provided adjacent to the left and right inner sides of the left and right hook portions 51, respectively.

The connecting shaft portion 93 is a cylindrical portion through which the rear support shaft 91 passes, and is constructed between the support portions 92a of the left and right lock claw portions 92 while being fixed to each lock claw portion 92 by welding or the like. There is. The left and right locking claws 92 and the connecting shaft 93 configure the rear locking member 85 as an integral rotating body that rotates with respect to the rear support shaft 91.

The rear lock member 85 rotates around the rear support shaft 91 at a rotation position in which the lock pieces 92b of the left and right lock claws 92 protrude downward from the arm portion 51a of the fixing hook 34 when viewed from the side. , the lock position is set to restrict separation of the support pin 36 from the fixed hook 34 after engaging with the fixed hook 34 (see FIG. 13B). That is, the rear locking member 85 rotates in a range from an unlocked position hidden within the outer shape of the arm portion 51a in a side view to a locked position as shown in FIG. 5 and the like. The rear locking member 85 changes from the unlocked position to the locked position by rotating counterclockwise (counterclockwise) as viewed from the left side shown in FIG. 5 .

The lock spring 86 is a biasing member that biases the rear locking member 85 in a rotational direction to a position (locking position) that restricts separation of the rear support pin 36 from the fixed hook 34 . In other words, the lock spring 86 biases the rear lock member 85 in the rotation direction from the unlocked position to the locked position regarding the rotation movement of the rear lock member 85 around the rear support shaft 91. In other words, the lock spring 86 biases the rear lock member 85 in the counterclockwise rotation direction when viewed from the left side.

The lock spring 86 is a so-called torsion spring, and has extending portions 86a and 86b at both ends of a coiled portion. The lock spring 86 is provided on the left and right outer sides of the left and right lock claw portions 92 of the rear lock member 85, with the rear support shaft 91 passing through the coiled portion. That is, two lock springs 86 are provided on the left and right sides on the rear support shaft 91, and one lock spring 86 is provided between the left lock claw portion 92 and the left hook portion 51, The other lock spring 86 is provided between the lock claw portion 92 on the right side and the hook portion 51 on the right side. The left and right lock springs 86 are provided in a symmetrical manner.

The lock spring 86 has an opening formed as a hole with an enlarged diameter on the left and right sides of the support hole 51d of the hook portion 51 that supports the left and right ends of the rear support shaft 91. It is located within 51e. The lock spring 86 has one extending portion 86a located on the left and right outer sides of the coiled portion locked with the hook portion 51 of the fixed hook 34, and the other extending portion 86a located on the left and right inner side of the coiled portion. 86b is engaged with a lock claw portion 92.

One of the extending portions 86a is engaged with the fixing hook 34 by bending the distal end toward the right and left outwards and inserting the end portion into the locking hole 51f opened in the left and right inner wall surface of the arm portion 51a in the hook portion 51. It has been stopped. The other extending portion 86b is locked to the rear locking member 85 by bending the tip portion toward the left and right inwards and inserting it into a locking hole 92f opened in the left and right outer wall surfaces of the lock claw portion 92. ing.

The lock spring 86 exerts a force to push down the lock piece 92b of the lock claw part 92 by a biasing force in a direction to separate the extension parts 86a and 86b from each other. As a result, the rear locking member 85 is biased against the fixed hook 34 in the rotation direction about the axis of the rear support shaft 91 from the unlocked position to the locked position.

The rotating arm body 87 is provided at the right rear part of the attachment attachment/detachment device 30. The rotating arm body 87 is rotatably supported with respect to the right cylinder support shaft 71R of the left and right cylinder support shafts 71 that support the rear end portion of the cylinder tube 61 of the first hydraulic cylinder 55. , is rotatably provided on the main body frame 31 side with the left-right direction as the rotation axis direction.

The rotating arm body 87 rotates under the pressure of the movable hook 33 that rotates rearward around the axis of the link support shaft 28, thereby moving the rear locking member 85 in the opposite direction to the locking position. Rotate. Here, regarding the rotation direction of the movable hook 33, when the rotation arm body 87 receives the pressing action from the movable hook 33, the rotation direction to the rear side is such that the movable hook 33 is not engaged with the front support pin 35. This is the direction to release it. Further, regarding the rotational direction of the rear locking member 85, the direction opposite to the locking position is the rotational direction from the locking position to the non-locking position, which is a clockwise direction when viewed from the left side.

The rotating arm body 87 includes a support base 101 that serves as a support portion for the cylinder support shaft 71R, and an operating protrusion that is a portion that extends from the support base 101 and that is abutted by the movable hook 33. portion 102 and an arm portion 103 that is a portion that engages with the rear locking member 85. The rotating arm body 87 is configured by the support base 101, the operating protrusion 102, and the arm portion 103 as an integral rotating body that rotates with respect to the cylinder support shaft 71R.

The support base 101 is a substantially disk-shaped portion having a thickness direction in the left-right direction and having a circular shape when viewed from the side. The support base 101 has a cylinder support shaft 71R passed through its center, and the rotation arm body 87 is supported by the cylinder support shaft 71R.

The operating protrusion portion 102 is an arm-shaped portion that is provided in a manner to hang downward from the lower front portion of the support base 101 . The operating protrusion portion 102 has a protrusion portion 102a at its tip portion, which is abutted by the movable hook 33 that rotates rearward. The protrusion 102a has a mountain shape with a convex front side when viewed from the side, and is brought into contact with the rear surface 46e of the hook portion 46 of the movable hook 33. The movable hook 33 rotates rearward in conjunction with the contraction operation of the first hydraulic cylinder 55 to press the operating protrusion 102 .

The arm part 103 includes an arm base 105 extending rearward from the support base 101, an arm tip 106 provided on the left side on the inside left and right with respect to the arm base 105, and the arm base 105 and the arm tip 106. It has a connecting plate part 107 which is a part that connects.

The arm base 105 is a rectangular plate-shaped portion whose thickness direction is the left-right direction. A rectangular plate-shaped connecting plate portion 107 is provided on the right side of the tip of the arm base portion 105 . The connecting plate portion 107 is a portion constructed between the distal end portion of the arm base portion 105 and the arm distal end portion 106.

The arm tip portion 106 is a plate-shaped portion whose thickness direction is in the left-right direction, and has an engagement recess 106a in the lower portion thereof with the rear side as the open side. The arm tip 106 forms an engagement recess 106a that is approximately "U" shaped when viewed from the side by having two upper and lower protrusions protrude diagonally rearward and downward at the lower part thereof. The arm distal end portion 106 has a distal end portion forming the engagement recess 106a located near the upper front side of the right locking claw portion 92R of the pair of left and right locking claw portions 92 of the rear locking member 85.

An engagement pin 110 fixed to the lock claw portion 92R is engaged with the engagement recess 106a of the arm tip 106. The engagement pin 110 is provided by a substantially "L"-shaped bent rod-shaped member fixed to the right side surface of the front upper part of the lock claw portion 92R by welding or the like.

The engagement pin 110 has a fixed shaft portion 110a that is fixed to the lock claw portion 92R and protrudes forward from the lock claw portion 92R, and a fixed shaft portion 110a that is bent at a right angle toward the left, which is inward from the fixed shaft portion 110a. It has an engaging shaft portion 110b. The engagement pin 110 is engaged with the arm tip 106 with the engagement shaft 110b positioned in the engagement recess 106a from the right side with respect to the arm tip 106.

According to the above configuration, the rotation of the rotating arm body 87 around the cylinder support shaft 71R (see arrow C1 in FIGS. 5 and 12) causes the arm portion 103 to rotate up and down (see FIGS. 12, see arrow C2), and is transmitted as rotation of the rear locking member 85 around the rear support shaft 91 (see arrow C3, FIGS. 5 and 12) via the engagement pin 110. Conversely, the rotation of the rear locking member 85 around the rear support shaft 91 is transmitted via the engagement pin 110 as rotation of the rotation arm body 87 around the cylinder support shaft 71R. In this way, the rotating arm body 87 and the rear locking member 85 constitute a rotating mechanism in which both members rotate in conjunction with each other.

The attachment and detachment operation of the bucket 20 by the attachment attachment and detachment device 30 will be explained using FIGS. 13 and 14. In addition, in FIG. 13 and FIG. 14, illustration of a part of structure of the attachment attachment/detachment device 30 is abbreviate|omitted for convenience.

The attachment attachment/detachment device 30 is in a first state when it is engaged with the bucket 20 and the bucket 20 is connected and supported in the excavation device 3 . In the first state of the attachment attachment/detachment device 30, the first hydraulic cylinder 55 is in an extended state, and the movable hook 33 is in a state farthest from the fixed hook 34.

Further, the attachment attachment/detachment device 30 is in a second state when it is disengaged from the bucket 20, which is a state before it is attached to the bucket 20 or after it is detached from the bucket 20. In the second state of the attachment attachment/detachment device 30, the first hydraulic cylinder 55 is in a shortened state, and the movable hook 33 is closest to the fixed hook 34.

That is, the attachment attachment/detachment device 30 has a first state in which the movable hook 33 and the fixed hook 34 are engaged with the front support pin 35 and the rear support pin 36 of the bucket 20, respectively, and a state in which the movable hook 33 and the fixed hook 34 are respectively engaged with the front support pin 35 and the rear support pin 36 of the bucket 20. A state in which the support pin is disengaged from the support pin (a state in which it is not engaged) is defined as a second state. Note that FIGS. 4 to 10 show the attachment attachment/detachment device 30 in the second state. Hereinafter, the first state of the attachment attachment/detachment device 30 will be referred to as an "engaged state", and the second state will be referred to as a "disengaged state".

The attachment/detachment operation of the bucket 20 by the attachment/detachment device 30 is performed by operating the excavator 3 or the like on the bucket 20 which is placed on the ground, etc. with the front support pin 35 and rear support pin 36 sides facing upward. This is done by moving 30.

That is, when attaching the bucket 20 to the attachment detachable device 30, the disengaged attachment detachable device 30 is brought close to the bucket 20 placed on the ground etc. by operating the excavator 3, etc. The bucket 20 is attached to the attachment attachment/detachment device 30 by bringing the attachment attachment/detachment device 30 into the engaged state while engaging the attachment attachment/detachment device 30 with the bucket 20 in the procedure.

On the other hand, when removing the bucket 20 from the attachment attachment/detachment device 30, place the bucket 20 on the ground etc. by operating the excavation device 3, etc., and remove the attachment while disengaging the attachment attachment/detachment device 30 from the bucket 20 according to a predetermined procedure. The bucket 20 is removed from the attachment attachment/detachment device 30 by disengaging the attachment/detachment device 30 and separating the attachment attachment/detachment device 30 from the bucket 20 by operating the excavation device 3 or the like.

First, the operation of the attachment attachment/detachment device 30 when attaching the bucket 20 to the attachment attachment/detachment device 30 (when the bucket is attached) will be described using FIG. 13. Note that when the attachment attachment/detachment device 30 is in the disengaged state, as shown in FIG. , the piston rod 77 is maintained in an extended state in which it protrudes from the cylinder tube 76 against the biasing force of the cylinder inner spring 79.

As shown in FIG. 13A, when the bucket is attached, the attachment attachment/detachment device 30 in a disengaged state is brought close to the bucket 20 by the operation of the excavation device 3 or the like, and the fixed hook 34 is moved by the movement operation of the attachment attachment/detachment device 30. , is engaged with the rear support pin 36 (see arrow D1).

Next, as shown in FIG. 13B, with the fixed hook 34 engaged with the rear support pin 36, the first hydraulic cylinder 55 is extended (see arrow D2). That is, as shown in FIG. 11, by the operation of the hydraulic pump 64, pressure oil is supplied from the supply pipe 68 to the bottom side chamber 61a through the bottom side hydraulic pipe 65 via the electromagnetic switching valve 67, and the first hydraulic cylinder 55 is activated. Stretch. Here, the electromagnetic switching valve 67 communicates the supply port (P) with the bottom cylinder port (A) and communicates the discharge port (T) with the rod side cylinder port (B) as the flow path switching state. The situation is as follows.

As the first hydraulic cylinder 55 extends, the movable hook 33 rotates forward around the link support shaft 28, and the hook portion 46 of the movable hook 33 is engaged with the front support pin 35 (see arrow D3). . The movable hook 33 rotates integrally with the front locking member 56 and the second hydraulic cylinder 57 supported on the hook support shaft 47.

Here, as the movable hook 33 rotates forward, the pressing action of the movable hook 33 on the operating protrusion 102 of the rotary arm body 87 is released (see arrow D4). As a result, the rear locking member 85, which was supported in the unlocked position by the rotating arm body 87, rotates around the rear support shaft 91 by the biasing force of the lock spring 86, and moves from the unlocked position to the locked position ( (See arrow D5). In other words, a locked state is obtained in which the rear locking member 85 restricts the rear support pin 36 engaged with the fixed hook 34 from disengaging from the fixed hook 34. As the rear locking member 85 rotates to the lock position, the arm portion 103 side of the rotating arm body 87 is pushed down via the engagement pin 110, and rotates around the cylinder support shaft 71 (as indicated by arrow D6). reference).

Further, as shown in FIG. 11, during the extension operation of the first hydraulic cylinder 55, the hydraulic oil discharged from the rod side chamber 61b to the rod side hydraulic pipe 66 as the piston 63 moves is transferred to the rod side hydraulic pipe 66 by the branch pipe 80. The pressure oil is supplied to the bottom side chamber 76a of the second hydraulic cylinder 57. As a result, the extended state of the second hydraulic cylinder 57 against the biasing force of the cylinder inner spring 79 is maintained.

As shown in FIG. 13B, the movable hook 33 engages with the front support pin 35 due to the extension operation of the first hydraulic cylinder 55, and when the extension of the first hydraulic cylinder 55 is stopped, the second hydraulic cylinder is connected via the branch pipe 80. The supply of pressure oil to 57 is stopped. As a result, as shown in FIG. 13C, the second hydraulic cylinder 57 automatically draws the piston rod 77 into the cylinder tube 76 and shortens it by the urging force of the cylinder inner spring 79 (see arrow D7).

By shortening the second hydraulic cylinder 57, the front locking member 56 connected to the piston rod 77 rotates around the hook support shaft 47, and moves (rotates) from the unlocked position to the locked position (arrow D8 reference). In other words, a locked state is obtained in which the front lock member 56 restricts the front support pin 35 engaged with the movable hook 33 from disengaging from the movable hook 33.

As described above, the attachment attachment/detachment device 30 is in the engaged state, and the movable hook 33 and the fixed hook 34 are engaged with the front and rear support pins (35, 36), respectively, as the bucket 20 is attached to the attachment attachment/detachment device 30. A locked state is obtained by the front and rear locking members (56, 85) at the engagement portions of the hooks (33, 34) with the support pins (35, 36).

Next, the operation of the attachment attachment/detachment device 30 when removing the bucket 20 from the attachment attachment/detachment device 30 (at the time of bucket removal) will be described using FIG. 14. The operation of the attachment attachment/detachment device 30 when removing the bucket is basically the reverse procedure of the operation when attaching the bucket.

As shown in FIG. 14A, from the state in which the attachment attachment/detachment device 30 is in the engaged state and the bucket 20 is attached, the second hydraulic cylinder 57 is first extended as shown in FIG. 14B (arrow (See E1). That is, as shown in FIG. 11, by the operation of the hydraulic pump 64, pressure oil is supplied from the supply piping 68 to the bottom side chamber 76a via the electromagnetic switching valve 67, the rod side hydraulic piping 66 and the branch piping 80, and the second Hydraulic cylinder 57 extends. Here, the electromagnetic switching valve 67 communicates the supply port (P) with the rod side cylinder port (B) and communicates the discharge port (T) with the bottom side cylinder port (A) as the flow path switching state. The situation is as follows.

As shown in FIG. 14B, as the second hydraulic cylinder 57 extends, the front locking member 56 connected to the piston rod 77 rotates around the hook support shaft 47 and moves from the locked position to the unlocked position ( rotation) (see arrow E2). In other words, the front locking member 56 provides an unlocked state in which the front support pin 35 engaged with the movable hook 33 can be disengaged from the movable hook 33.

Next, as shown in FIG. 14C, an operation is performed to shorten the first hydraulic cylinder 55 (see arrow E3). That is, as shown in FIG. 11, pressure oil is supplied to the rod side chamber 61b via the electromagnetic switching valve 67 and the rod side hydraulic piping 66 by the operation of the hydraulic pump 64, and the first hydraulic cylinder 55 is shortened.

Here, according to the hydraulic circuit configuration (see FIG. 11) included in the excavating work machine 1, the shortening operation of the first hydraulic cylinder 55 is performed after the extending operation of the second hydraulic cylinder 57 is performed. The second hydraulic cylinder 57 is a hydraulic cylinder that is sufficiently smaller than the first hydraulic cylinder 55. Therefore, when pressure oil is supplied from the rod side hydraulic piping 66 to the rod side chamber 61b of the first hydraulic cylinder 55, the pressure oil is supplied to the second hydraulic cylinder 57 by the branch piping 80 branched from the rod side hydraulic piping 66. Therefore, the second hydraulic cylinder 57 performs the extension operation before the first hydraulic cylinder 55 performs the shortening operation.

By shortening the first hydraulic cylinder 55, the movable hook 33 rotates rearward around the link support shaft 28, and the engagement of the hook portion 46 of the movable hook 33 with the front support pin 35 is released (arrow E4 reference).

Here, as the movable hook 33 rotates rearward, the movable hook 33 presses the operating protrusion 102 of the rotary arm body 87 toward the rear (see arrow E5). As a result, the rotating arm body 87 rotates around the cylinder support shaft 71 in a direction that raises the arm portion 103 (see arrow E6). As the rotating arm body 87 rotates, the rear locking member 85, which had been supported in the lock position by the biasing force of the lock spring 86, rotates around the rear support shaft 91 in conjunction with the rotating movement of the rotating arm body 87. , and moves from the locked position to the unlocked position (see arrow E7). In other words, an unlocked state is obtained in which the rear support pin 36 is allowed to separate from the fixing hook 34.

As described above, the attachment attachment/detachment device 30 is brought into the disengaged state. Then, the fixing hook 34 is disengaged from the rear support pin 36 by moving the attachment attachment/detachment device 30 by operating the excavator 3 or the like (see arrow E8), and the bucket 20 is removed from the attachment attachment/detachment device 30.

According to the attachment attachment/detachment device 30 and the excavation work machine 1 equipped with the same according to the present embodiment as described above, even when the supply of hydraulic pressure to the first hydraulic cylinder 55 and the second hydraulic cylinder 57 as actuators is cut off, Even if the bucket 20 is connected, the connected state of the bucket 20 can be maintained and high safety can be achieved.

The attachment attachment/detachment device 30 of this embodiment holds the front locking member 56 at the lock position by the biasing force of the cylinder inner spring 79 of the second hydraulic cylinder 57. The front locking member 56 is moved from the locked position to the unlocked position by hydraulic operation of the second hydraulic cylinder 57.

According to such a configuration, good workability can be obtained in attaching and detaching the bucket 20 to and from the attachment attaching/detaching device 30, and even if the power supply to the second hydraulic cylinder 57 is cut off due to damage to the hydraulic equipment, for example, Even if the movable hook 33 is locked to the front support pin 35 by the front locking member 56, the urging force of the cylinder inner spring 79 ensures that the movable hook 33 is locked with respect to the front support pin 35. Thereby, safety can be ensured.

The attachment attachment/detachment device 30 also includes a cylinder internal spring 79 provided within the second hydraulic cylinder 57 as a structure for holding the front locking member 56 in the locked position. According to such a configuration, there is no need to separately provide a biasing member for holding the front locking member 56 in the locked position, so that the attachment attaching/detaching device 30 can be designed compactly.

In addition to the front locking member 56, the attachment attaching/detaching device 30 according to this embodiment includes a rear locking member 85 that prevents the rear support pin 36 of the bucket 20 from falling off from the fixing hook 34. That is, the attachment attachment/detachment device 30 has a double lock structure in which locking members (56, 85) are provided for each of the movable hook 33 and the fixed hook 34. According to such a configuration, detachment of the bucket 20 from the attachment attachment/detachment device 30 can be effectively prevented, and safety can be improved.

In particular, the attachment attachment/detachment device 30 holds the rear locking member 85 in the locked position by the biasing force of the locking spring 86. The rear locking member 85 is moved from the locked position to the unlocked position by the movement of the rotating arm body 87 in conjunction with the hydraulic movement of the first hydraulic cylinder 55.

According to such a configuration, good workability can be obtained in attaching and detaching the bucket 20 to and from the attachment attaching/detaching device 30, and even if the power supply to the first hydraulic cylinder 55 is cut off due to damage to the hydraulic equipment, for example, Even if there is, the biasing force of the lock spring 86 ensures that the fixed hook 34 is locked to the rear support pin 36 by the rear lock member 85. Thereby, safety can be ensured.

In addition, in the attachment attachment/detachment device 30, the rotating arm body 87 engages with the operating protrusion portion 102 that receives contact with the movable hook 33 that rotates in conjunction with the operation of the first hydraulic cylinder 55, and the rear locking member 85. It has an arm portion 103 that fits together.

According to such a configuration, it becomes possible to efficiently transmit the expansion and contraction operation of the first hydraulic cylinder 55 to the rear locking member 85 with a simple configuration. Thereby, good operability can be obtained in the attachment/detachment operation of the bucket 20 to/from the attachment attachment/detachment device 30.

Further, in the attachment attachment/detachment device 30, the second hydraulic cylinder 57 is disposed between the first hydraulic cylinder 55 and the right body frame body 41 between the left and right body frame bodies 41 of the body frame 31.

According to such a configuration, the space between the first hydraulic cylinder 55 and the main body frame body 41 can be used as the operating space for the second hydraulic cylinder 57, so that the attachment attaching/detaching device 30 can be designed compactly. I can do it.

The description of the embodiments described above is an example of the present invention, and the attachment attachment/detachment device and construction machine according to the present invention are not limited to the embodiments described above. Therefore, it goes without saying that various changes can be made to the embodiments other than those described above, depending on the design, etc., as long as they do not deviate from the technical idea of the present invention.

For example, in the embodiment described above, the second hydraulic cylinder 57 is disposed between the right main body frame body 41 and the first hydraulic cylinder 55 among the left and right main body frame bodies 41; 41 and the first hydraulic cylinder 55.

Furthermore, in the embodiment described above, the hydraulic circuit configuration (see FIG. 11) for operating the first hydraulic cylinder 55 and the second hydraulic cylinder 57 is merely an example. That is, as long as the above-mentioned operation of the first hydraulic cylinder 55 and the second hydraulic cylinder 57 can be obtained when the bucket is attached and when the bucket is removed, the hydraulic circuit configuration for operating these hydraulic cylinders is as follows. Not particularly limited.

Further, in the embodiments described above, both the first actuator and the second actuator are hydraulic cylinders, but the actuator according to the present invention is not limited to a hydraulic cylinder, and may be, for example, an electrically driven cylinder mechanism. It's okay.

1 Excavation machine (construction machine)
2 Traveling device 3 Excavation device (front working device)
18 Arm 20 Bucket (attachment)
30 Attachment attachment/detachment device 31 Main body frame 33 Movable hook (first hook)
34 Fixed hook (second hook)
35 Front support pin (first engaged part)
36 Rear support pin (second engaged part)
41 Main frame body (wall part)
55 First hydraulic cylinder (first actuator)
56 Front lock member (removal prevention member)
57 Second hydraulic cylinder (second actuator)
77 Piston rod (movable part)
79 Cylinder inner spring (biasing member)
85 Rear locking member (second retaining member)
86 Lock spring (second biasing member)
87 Rotating arm body (rotating operation member)
102 Operation protrusion part (abutted part)
103 Arm portion 110 Engagement pin

Claims (5)

An attachment attachment/detachment device for construction machinery that attaches and detaches a work attachment to and from an arm of a work device,
a main body frame connected to the arm;
a first hook rotatably provided on the main body frame and engaged with a first engaged portion of the attachment;
a second hook provided on the main body frame and engaged with a second engaged portion of the attachment;
a first actuator that rotates the first hook with respect to the main body frame;
a retaining member that is rotatably provided on the first hook and that restricts separation of the first engaged portion that has been engaged with the first hook from the first hook;
a second actuator provided on the first hook and connected to the retaining member to rotate the retaining member;
The second actuator is
a movable part that operates upon receiving power and rotates the retaining member in a direction opposite to a direction in which the retaining member is in a lock position that restricts the detachment of the first engaged part;
An attachment attachment/detachment device for a construction machine, comprising: a biasing member that biases the movable part in a rotational direction in which the retaining member is in the lock position. a second retaining member that is rotatably provided on the main body frame and that restricts separation of the second engaged portion that is engaged with the second hook from the second hook;
a second biasing member that biases the second retaining member in a rotational direction to a lock position that restricts the detachment of the second engaged portion;
The second hook is rotatably provided on the body frame side and rotates in response to the pressing action of the first hook, which rotates in a direction to release the engagement with the first engaged portion. The attachment attachment/detachment device for a construction machine according to claim 1, further comprising: a rotation operation member configured to rotate the retaining member in a direction opposite to the locking position. The construction according to claim 2, wherein the rotation operation member has a contact portion that receives contact with the first hook, and an arm portion that engages with the second retaining member. Machine attachment attachment/detachment device. The main body frame has a pair of left and right walls,
The first actuator is provided between the left and right walls,
The construction according to any one of claims 1 to 3, wherein the second actuator is disposed between one of the left and right walls and the first actuator. Machine attachment attachment/detachment device. An attachment attachment/detachment device for construction machinery according to any one of claims 1 to 4;
a traveling device;
A construction machine, comprising: a front working device that is provided on the front side of the travel device and includes the arm that removably supports the attachment by the attachment attachment/detachment device.

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