JP4197682B2 - Locking device for work equipment - Google Patents

Description

  The present invention relates to a lock device that prevents a work machine of a construction machine from being inclined by its own weight, and more particularly to a lock device that prevents a boom in a work machine of a backhoe from rotating downward due to its own weight.

  Conventionally, a so-called tractor loader backhoe in which a loader is attached to the front part of a traveling vehicle and a backhoe is attached to the rear part is known. This type of tractor / loader / backhoe supports a boom by standing a side column on the front side frame of the tractor, and supports a bucket at the front end of the boom. The front loader is configured so as to be able to. Further, a boom is supported at the rear part of the tractor so that the boom can be turned up and down and turned left and right, an arm is supported at the tip of the boom so that it can be turned up and down, and a bucket is supported at the tip of the bucket so that it can be turned up and down. The backhoe is configured so that it can be rotated with the.

  And the operation of the front loader is operated by an operation unit arranged on the side of the seat, and the backhoe is reversed by moving the seat back and forth so that it can be operated by a lever or the like provided on an operation column standing on the rear frame. .

  By the way, since the tractor / loader / backhoe is driven by wheels, it can be driven at a relatively high speed. When the loader or backhoe, which is a work machine, is lowered due to vibration, hydraulic pressure leakage, or the like during the traveling, traveling is hindered. Therefore, a technique for locking the work machine when the work machine is not operated is known (for example, see Patent Document 1).

JP 2004-360331 A

  However, in the case of the technique of Patent Document 1, the movement of the operation lever is constrained, and when the hydraulic pressure leaks, the work implement is lowered by its own weight. Therefore, there is a technique for mechanically preventing the descent. For example, there is a technique in which a lock member is provided at the rotation base of the boom, the operation member is extended from an operation column, and the lock member is operated to lock the boom. However, since the operation member and the lock member are always in contact with each other, friction is generated every time each mechanism is operated, the contact portion is worn, rust is generated, and the life is shortened. It was.

  Therefore, the present invention provides a non-contact portion on the member connecting the operating member and the locking device so that the rotating portion in the middle of the connecting member does not always come into contact so that the contact can be locked only during the locking operation. Is.

  The problems to be solved by the present invention are as described above. Next, means for solving the problems will be described.

In a tractor backhoe having a drilling device (3) mounted on one of the work vehicles (1), the boom (16) of the drilling device (3) is turned up and down and turned left and right on one of the work vehicles (1). The arm (17) is supported at the tip of the boom (16) so as to be rotatable up and down, and the bucket (18) is supported at the tip of the boom (16) so as to be rotatable up and down. The seat (6) can be operated by turning the seat (6) upside down by the lever of the operation column (11) erected on the work machine frame (13) of the work vehicle (1), and the excavator (3) is not operated. A lock device (31) for a work machine that locks the boom (16) to the work vehicle (1) is provided so that the excavator (3) does not descend during traveling, and the lock device (31) (16) provided with a lock pin (32) A lock arm (33) is provided on the boom brackets (15) on both sides (1), and the lock arm (33) is connected to a lock operation mechanism (34) including an operation pedal (45) to 6) The lock operation can be performed by depressing the operation pedal (45), and the lock operation mechanism (34) is supported by the boom bracket (15) and connected at one end to the lock arm (33). The moving side operation unit (34b) and the fixed side operation unit (34a) supported on the work vehicle (1) side and connected at one end to the operation pedal (45) are configured. The rotation side operation unit (34b) The pivot plate (27), which is the left and right pivot point of the boom bracket (15), is connected to the abutment plate (37) at the other end and the abutment arm (39) at the other end of the fixed side operation portion (34a). Placed above and locked Except, when said abutment plate (37) both contact arms (39) and a non-contact state, overlapping arrangement in plan view, to unlock the drilling device (3) is the manipulation pedal By turning downward (45), the contact arm (39) is rotated upward, and is brought into contact with the contact plate (37) from the lower side so that the contact plate (37) is moved upward. When the excavator (3) is locked when the lock arm (33) is rotated upward via the rotation side operation section (34b) to be detached from the lock pin (32). By depressing the operation pedal (45), the corresponding contact arm (39) is rotated upward, the corresponding contact plate (37) is rotated upward, and the lock arm (33) is rotated upward. Next, the boom (16) is rotated upward to the stroke end, and in this state, the operation pedal is turned on. When the lug (45) is opened, the lock arm (33) rotates downward due to its own weight and engages with the lock pin (32) .

  As effects of the present invention, the following effects can be obtained.

According to the first aspect of the present invention, when the lock device is not operated, there is no contact between the rotation side operation unit and the fixed side operation unit. Thus, wear does not occur, durability can be improved, and malfunctions in the operation mechanism can be reduced.
That is, the front end (rear end) of the contact arm 39 is positioned above the axial extension of the pivot pin 27 and positioned below the contact plate 37, and the contact plate 37 and the contact arm A gap is provided between the tip of 39.
That is, the rotation-side operation unit 34b and the fixed-side operation unit 34a are not connected (contacted), and are not contacted with the rear end of the fixed-side operation unit 34a below the contact plate 37 at the front end of the rotation-side operation unit 34b. The abutting arm 39 is positioned. In other words, the front end of the rotation side operation unit 34b and the rear end of the fixed side operation unit 34a overlap in plan view, but have a slight gap in side view.
With this configuration, even if the boom bracket 15 is rotated left and right around the pivot pin 27, the rotation side operation unit 34b and the fixed side operation unit 34a, that is, the contact plate 37 and the contact arm 39 are provided. Are not in contact with each other and wear is not generated between them, and the life of the lock operating mechanism 34 can be extended.
When the excavator (3) is unlocked, the contact arm (39) is rotated upward by depressing the operation pedal (45), and the contact The contact plate (37) is contacted from the lower side, the contact plate (37) is rotated upward, the lock arm (33) is rotated upward via the rotation side operation portion (34b), and the lock When the excavator (3) is to be detached from the pin (32) and the excavator (3) is locked, the contact arm (39) is rotated upward by the stepping operation of the operation pedal (45), and the contact plate (37 ) Upward, the lock arm (33) is rotated upward, the boom (16) is then rotated upward to the stroke end, and the operation pedal (45) is released in this state, The lock arm (33) is rotated downward by its own weight, and the lock pin (33) is rotated. Since it is configured to engage with (32), the unlocking and locking operations can be performed by depressing the operation pedal (45), so that the operator can operate with the foot without manually unlocking and locking. By depressing the pedal (45), the operation can be performed strongly and reliably.

  Next, embodiments of the invention will be described.

  1 is an overall side view of a work vehicle according to the present invention, FIG. 2 is a side view of a lock device, FIG. 3 is a perspective view of the lock device, and FIG. 4 is an enlarged view of a non-contact portion.

  First, the overall configuration will be described. A work vehicle 1 shown in FIG. 1 is a tractor loader backhoe, and is equipped with a loader 2 and an excavator 3. A control unit 4 is provided at the center of the work vehicle 1, a loader 2 is disposed in front of the control unit 4, and a backhoe is disposed as an excavator 3 behind the control unit 4. The work vehicle 1 is equipped with front wheels 8 and 8 and rear wheels 7 and 7, and is configured to be able to travel with the loader 2 and the excavator 3 attached thereto.

  A steering handle 5 and a seat 6 are disposed in the control unit 4, and a traveling operation device and an operation device for the loader 2 are disposed on the side of the seat 6. Thereby, in the control part 4, the steering operation of the work vehicle 1 and the operation of the loader 2 are enabled.

  A loader 2 as a loading device is connected to a side portion of the work vehicle 1 and extends forward, and a bucket is attached to the tip. An engine is disposed in the front portion of the frame 9 that is a chassis of the work vehicle 1, and a bonnet 30 disposed on the frame 9 covers the engine. The loader 2 is disposed outside the bonnet 30.

  The excavator 3 is detachably attached to the rear portion of the work vehicle 1, and the operation of the excavator 3 is performed by a lever or the like on the operation column 11 disposed behind the cockpit 6.

  A hydraulic oil tank 90 is disposed on the side of the control unit 4, and the hydraulic oil tank 90 also serves as a staircase for getting on and off the control unit 4. On the opposite side of the control unit 4, A staircase composed of a fuel tank is provided.

  At the rear end of the frame 9 is provided a mounting portion for mounting the work implement, and the work implement frame 13 of the excavator 3 is fixed to this mounting portion. An operation column 11 is erected on the left and right center of the work machine frame 13, and an operation lever and the like are disposed on the operation column 11. Stabilizers 10 are provided on the left and right sides of the work machine frame 13, and can be turned up and down by expansion and contraction of the hydraulic cylinder 20. A boom bracket 15 is attached to the rear portion of the work machine frame 13 so as to be able to turn left and right around the vertical axis, and can be turned left and right by a hydraulic cylinder (not shown). The base of the boom 16 is pivotally attached to the rear part of the boom bracket 15 so as to be rotatable up and down around the left and right axis, and can be rotated forward and backward by a boom cylinder 21. A base portion of the arm 17 is pivotally attached to the distal end side of the boom 16 so as to be rotatable up and down around a left and right axis, and can be turned up and down by an arm cylinder 22. A bucket 18 is swingably attached to the distal end side of the arm 17 via a link mechanism, and can swing by a bucket cylinder 23.

  As shown in FIG. 2, the boom bracket 15 is formed in a substantially U-shape when viewed from the side, and support portions 15a and 15b are formed in the front upper portion and the lower portion, and support holes are formed in the support portions 15a and 15b in the vertical direction. The boom bracket 15 and the work implement frame 13 are pivotally supported by pivot pins 27 and 27 serving as left and right pivots, so that the boom bracket 15 can be supported to be pivotable left and right at the rear left and right center of the work implement frame 13. I have to. The pivot brackets 15c and 15c are formed at the lower portions of the left and right sides of the boom bracket 15, and support holes are opened in the vertical directions in the pivotal supports 15c and 15c, respectively, so that the tip of the swing cylinder can be pivoted. The boom bracket 15 can be turned left and right by the cylinder. A support portion 15 d protrudes rearward from the rear lower portion of the boom bracket 15, a support hole is opened in the left-right direction in the support portion 15 d, and the lower portion of the boom 16 is pivotally supported by a pivot pin 25. A support hole is opened in the left and right direction at the rear upper part of the boom bracket 15, and the lower part of the boom cylinder 21 is pivotally supported by the pivotal support pin 26.

  Next, the locking device 31 of the present invention will be described with reference to FIGS.

  The lock device 31 includes a lock pin 32 that is provided on the boom 16 on the work machine side and serves as a locked member, a lock arm 33 that serves as an engagement member on the machine side that engages with the lock pin 32, and the lock arm A lock operation mechanism 34 or the like serving as an operation member for rotating the 33 is provided.

  The lock pin 32 is provided so as to project horizontally outward from the side surface of the boom 16, and the lock pin 32 is disposed from a pivot pin 25 that pivotally supports the base of the boom 16 on the boom bracket 15. It is disposed at a position separated by a predetermined distance. In this embodiment, since the lock arms 33 are provided on the left and right, the lock pins 32 protrude from the left and right sides of the boom 16 on both sides. However, the lock pin 32 can also be arranged inside the left and right side plates of the boom 16, and is not limited to the pin, and can be constituted by a plate, a concave portion or the like.

  The lock arm 33 is formed in a substantially “J” shape, has a C-shaped hook portion 33a at one end, opens the lower side, and the rear end surface 33d is inclined so as to go down to the open side at the center in the longitudinal direction. In FIG. 2, it is configured to be inclined forward and downward. A pivot support hole 33b is opened on the rotation base side that is the other end of the lock arm 33, and a pivot support pin 26 that pivotally supports the boom cylinder 21 is inserted into the boom bracket 15 in the pivot support hole 33b. Be supported. A pin hole 33c serving as a connecting portion with a connecting arm 35 to be described later is opened on the rotating base side of the lock arm 33.

  The operation mechanism 34 of the lock arm 33 includes a front-side fixed-side operation unit 34 a disposed on the work machine frame 13 and a rear-side turn provided on the boom bracket 15 that is rotatably supported by the work machine frame 13. The rotation side operation unit 34b includes a connecting arm 35, a rotation arm 36, a contact plate 37, a rotation side support 38, and the like, and the fixed side operation unit 34a includes a contact arm 39 and an arm. 40, a connecting plate 41, an operation pedal 45, a fixed-side support 42, and the like.

  The rotation-side support body 38 in the rotation-side operation section 34b has left and right plates standing on the upper surface of the boom bracket 15, and the left and right plates have pivot pins 27 that pivotally support the boom bracket 15 in the left-right rotation. It is arranged in parallel across the straddle. That is, the rotation side support body 38 is erected on both sides of the left and right rotation fulcrum of the boom bracket 15. A pivot arm 43 and a contact plate 37 are pivotally supported on the upper end of the plate by horizontally supporting a pivot pin 43 in the left-right direction.

  The pivot arm 36 and the abutment plate 37 are integrally fixed to the boss body, and pivotally supported by the pivot pin 43. The pivot arm 36 extends rearward and downward to connect the connecting arm 35. It is pivotally connected to the front end. The abutment plate 37 projects forward as left and right surfaces and is positioned above the pivot pin 27.

  The connecting arm 35 is formed in a substantially Y shape in plan view, the front end is pivotally supported by the rear end of the rotating arm 36, and the rear portion of the connecting arm 35 is bifurcated. The left and right lock arms 33, 33 are extended to the front side and pivoted. The rear portion of the connecting arm 35 is configured in a side-view shape and is disposed around the upper part of the pivot pin 26 to avoid interference when locked.

  The fixed-side support 42 in the fixed-side operation unit 34 a has a plate standing on the work machine frame 13 in front of the operation column 11, and a pivot pin 46 is pivotally supported on the upper part of the fixed-side support 42. The boss body 47 is pivotally supported by the pivot pin 46, and the contact arm 39 and the arm 40 are fixed to the boss body 47 so as to rotate integrally.

  The arm 40 protrudes upward from the left and right sides of the boss body 47, and a connecting plate 41 is pivotally supported at the tip of the arm 40. The front end of the connection plate 41 is connected to an operation pedal 45 serving as an operation member. The operation pedal 45 has a boss formed at the base thereof, and the boss is rotatably supported by a pivot pin 48 projecting laterally from the lower side of the side surface of the operation column 11. An arm 45a projects from the rear, and the front end of the connecting plate 41 is pivotally supported by the arm 45a. One end of a spring 49 is further locked to the arm 45 a, the other end of the spring 49 is locked to the operation column 11 or the work machine frame 13, and the tip of the contact arm 39 is away from the contact plate 37. Energized. That is, the contact arm 39 is urged to rotate downward and the operation pedal 45 to rotate upward.

  The abutment arm 39 protrudes rearward from the boss body 47, the rear portion of the contact arm 39 is formed in a "<" shape when viewed from the side, and the tip thereof is formed in a pointed shape so as to face obliquely upward. It is configured. Further, the front end (rear end) of the abutting arm 39 is positioned above the axial center of the pivot pin 27 and positioned below the abutting plate 37, and is in contact with the corresponding abutting plate 37. A gap is provided between the tip of the arm 39. That is, the rotation-side operation unit 34b and the fixed-side operation unit 34a are not connected (contacted), and are not contacted with the rear end of the fixed-side operation unit 34a below the contact plate 37 at the front end of the rotation-side operation unit 34b. The abutting arm 39 is positioned. In other words, the front end of the rotation side operation unit 34b and the rear end of the fixed side operation unit 34a overlap in plan view, but have a slight gap in side view.

  With this configuration, even if the boom bracket 15 is rotated left and right around the pivot pin 27, the rotation side operation unit 34b and the fixed side operation unit 34a, that is, the contact plate 37 and the contact arm 39 are provided. Are not in contact with each other and wear is not generated between them, and the life of the operation mechanism 34 can be extended.

  Next, locking and unlocking operations will be described.

  When working with the excavator 3, the lock arm 33 is separated from the lock pin 32, and when the work is finished and the vehicle is traveling, performing loader work, or storing, first, the operation pedal 45 is turned off. Step on. By this stepping operation, the operation pedal 45 is rotated downward, the connecting plate 41 is pulled forward, and the contact arm 39 is rotated upward. The contact arm 39 is brought into contact with the contact plate 37 by the upward rotation of the contact arm 39, the corresponding contact plate 37 is rotated upward, the rotation arm 36 is rotated forward, and the connecting arm 35 is pulled forward. Then, the lock arm 33 is rotated upward. Then, the boom cylinder 21 is reduced, and the boom 16 is rotated forward (to the control unit 4 side) to the stroke end. When the operation pedal 45 is released in this state, the lock arm 33 is rotated downward by its own weight, and the lock pin 32 is engaged with the hook portion 33a to be locked. On the other hand, when the operation pedal 45 is released, the fixed side operation portion 34a is returned to the original position by the biasing force of the spring 49. Thus, even if the hydraulic pressure leaks, the boom 16 is locked by the locking device 31 and thus does not rotate forward.

Next, in order to release the lock for working with the excavator 3, when the operation pedal 45 is depressed, the connection plate 41 is pulled forward by the downward rotation of the operation pedal 45 as described above. As a result, the contact arm 39 is rotated upward. The contact arm 39 is brought into contact with the contact plate 37 by the upward rotation of the contact arm 39, the corresponding contact plate 37 is rotated upward, the rotation arm 36 is rotated forward, and the connecting arm 35 is pulled forward. Then, the lock arm 33 is rotated upward. Thus, the hook portion 33a is released from the lock pin 32 and the lock is released. Then, when the boom 16 is rotated rearward and the depression of the operation pedal 45 is released, the fixed-side operation unit 34 a is returned to the original position by the biasing force of the spring 49, and the rotation-side operation unit 34 b is connected to the lock arm 33. Returns to its original position due to its own weight . However, when the operation pedal 45 is not fully depressed, when the boom 16 is rotated to the foremost part, the lock pin 32 comes into contact with the rear end surface 33d of the lock arm 33 and the inclined portion of the rear end surface 33d of the lock arm 33 is reached. The lock pin 32 is lifted by sliding on the outer periphery of the lock pin 32, and the lock pin 32 is engaged with the hook portion 33a to be in a locked state so that the lock device is not damaged.

  The lock device of the present invention can be applied to lock the boom, arm, etc. in the state of being housed on the machine body side, and can be used for excavators, loaders, cranes and the like.

The whole side view of the work vehicle of this invention. The side view of a locking device. The perspective view of a locking device. The enlarged view of a non-contact part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 3 Excavator 4 Control part 15 Boom bracket 16 Boom 27 Pivot pin (left-right rotation fulcrum)
31 Locking device 32 Lock pin (engaged member)
33 Lock arm (engagement member)
34 Operation mechanism 34a Fixed operation unit 34b Rotation operation unit

Claims (1)

In a tractor backhoe having a drilling device (3) mounted on one of the work vehicles (1), the boom (16) of the drilling device (3) is turned up and down and turned left and right on one of the work vehicles (1). The arm (17) is supported at the tip of the boom (16) so as to be rotatable up and down, and the bucket (18) is supported at the tip of the boom (16) so as to be rotatable up and down. The seat (6) can be operated by turning the seat (6) upside down by the lever of the operation column (11) erected on the work machine frame (13) of the work vehicle (1), and the excavator (3) is not operated. A lock device (31) for a work machine that locks the boom (16) to the work vehicle (1) is provided so that the excavator (3) does not descend during traveling, and the lock device (31) (16) provided with a lock pin (32) A lock arm (33) is provided on both (1) boom brackets (15), and the lock arm (33) is connected to a lock operation mechanism (34) including an operation pedal (45) to 6) The lock operation can be performed by depressing the operation pedal (45), and the lock operation mechanism (34) is supported by the boom bracket (15) and connected at one end to the lock arm (33). The moving side operation unit (34b) and the fixed side operation unit (34a) supported on the work vehicle (1) side and connected at one end to the operation pedal (45) are configured. The rotation side operation unit (34b) The pivot plate (27), which is the left and right pivot point of the boom bracket (15), is connected to the abutment plate (37) at the other end and the abutment arm (39) at the other end of the fixed side operation portion (34a). Placed above and locked Except, when said abutment plate (37) both contact arms (39) and a non-contact state, overlapping arrangement in plan view, to unlock the drilling device (3) is the manipulation pedal By turning downward (45), the contact arm (39) is rotated upward, and is brought into contact with the contact plate (37) from the lower side so that the contact plate (37) is moved upward. When the excavator (3) is locked when the lock arm (33) is pivoted upward via the pivot side operation section (34b) to be detached from the lock pin (32). By depressing the operation pedal (45), the corresponding contact arm (39) is rotated upward, the corresponding contact plate (37) is rotated upward, and the lock arm (33) is rotated upward. Next, the boom (16) is rotated upward to the stroke end, and in this state, the operation pedal is turned on. When the lock (45) is opened, the lock arm (33) rotates downward by its own weight and engages with the lock pin (32) .

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