JP4519768B2 - Quick coupler for work vehicle - Google Patents

Description

The present invention relates to a quick coupler that is mounted on a work vehicle such as a wheel loader and is used to quickly attach and detach a work tool such as a bucket.

A wheel loader having a lift arm as a work arm to which a work tool is attached, which is a representative example of a work vehicle, performs various work by appropriately replacing various work tools at the tip of the lift arm. Can do.

A quick coupler, which is a quick attachment / detachment device capable of quickly attaching / detaching a work tool, has been developed and put into practical use (see, for example, Patent Document 1). Using a quick coupler, various work tools of different types, shapes, sizes, etc., such as buckets, forks, gripping devices, etc., can be exchanged as needed, and various wheel loaders can be used. Can be used efficiently, efficiently and versatilely for various operations and applications.

A representative example of a quick coupler (see, for example, Patent Document 1) is equipped with pins at the ends of a pair of lift arms that are provided at predetermined intervals in the left-right width direction of the vehicle body. Are detachably connected by hooks and pins.

To connect the work tool to the quick coupler, first hook the hook of the work tool on the hitch of the coupler body, insert the pin for fixing the coupler body into the work tool using the manual operation lever, and connect the work tool and the coupler body. Fix it. To remove the work tool from the quick coupler, an operation reverse to the coupling operation may be performed.

The operation lever is formed in a relatively long shape at a position where the operator can easily operate, and at a position where the fixing pin is inserted through the work tool from the driver's seat of the work vehicle. Yes.
Japanese Patent Laid-Open No. 2-47431 (FIG. 1)

However, the conventional quick coupler having the above-described configuration has the following problems to be solved.

The quick coupler is positioned between the work arm and the work tool, and the operation lever protrudes from the coupler main body and is provided as far as possible in the left-right width direction for operability and visibility. Therefore, for example, if the operating lever is deformed by contacting an obstacle during work, and the work arm, work tool, etc. are operated in this state, the operation lever, work arm, work tool, etc. interfere with each other and the operation lever moves. As a result, the fixing pin comes out of the working tool, and the fixing pin is not sufficiently inserted into the working tool. Further, if the operation is continued with the fixing pin pulled out, the fixing pin and the portion of the insertion hole are easily damaged by earth and sand.

Further, when the operation lever is deformed, it is difficult to visually confirm from the driver's seat whether the fixing pin is sufficiently inserted into the work tool. Therefore, the operator has to get out of the driver's seat and directly check the insertion state of the fixed pin, which is troublesome and the work is interrupted.

The present invention has been made in view of the above-described facts, and a technical problem thereof is a quick coupler that is mounted on a work arm of a work vehicle and removably connects a work tool by inserting and removing the fixed pin with an operation lever. In the “fixed position” where the operating lever is inserted and inserted into the work tool, the operation lever can be held even if it interferes with an obstacle, etc. It is to provide a quick coupler for a work vehicle.

According to the present invention, as a quick coupler that solves the above technical problems, a coupler body that is mounted on a work arm of a work vehicle and that removably connects a work tool, and a coupler body that is detachably inserted into the work tool. a fixing pin for releasably securing the coupling state between the coupling body and the work implement and is connected via a link mechanism to the fixed pin was withdrawn inserting the fixing pin to implement a "fixed position" from the implement " An operation lever that operates to the `` release position '', a spring that is provided in the link mechanism and biases the fixing pin in the `` fixed position '' direction when in the `` fixed position '' and in the `` release position '' direction when in the `` release position '', releasably engages the fixing pin, provided with a locking means for releasably locking the movement of the fixing pin in the direction of "release position" from the "locking position", the locking means, the fixing pin A locking groove formed on the outer periphery in a direction perpendicular to the axis of the fixing pin, and a swinging in a direction orthogonal to the axis near the fixing pin insertion hole of the coupler main body, which is detachably engaged with the locking groove. moving freely, and a mounted locking plate above the insertion hole in the swinging center, Ru retained engagement of locking plate and the locking groove is due to the weight of the locking plate, it and characterized A working vehicle quick coupler is provided.

The quick coupler of the work vehicle configured according to the present invention can be releasably engaged with a fixing pin that connects the coupler main body and the work tool, and can be released into a "fixed position" state where the fixing pin is inserted into the work tool. Locking means for locking is provided.

Therefore, since the fixing pin is locked in the “fixed position” state by the locking means, the fixing pin is held in the “fixed position” even if the operation lever interferes with an obstacle or the like. Further, since the fixing pin is locked at the “fixed position” by the locking means, the trouble that the operator has to visually recognize the insertion state of the fixing pin is also eliminated.

Hereinafter, a quick coupler constructed according to the present invention will be described in more detail with reference to the accompanying drawings illustrating a preferred embodiment of a wheel loader which is a typical work vehicle.

A description will be given with reference to FIG. 4 which is a side view of a wheel loader equipped with a quick coupler and a bucket as a work tool. The wheel loader indicated as a whole by number 2 is a refractor in which a front vehicle body 6 and a rear vehicle body 8 each having a pair of wheels 4 and 4 in the left-right width direction (direction perpendicular to the paper surface of FIG. 4) are connected in a refractive manner. It has a steering-type body.

The front vehicle body 6 includes a pair of lift arms 10 and 10 that are integrally formed at intervals in the left-right width direction, which are work arms that are swingably mounted in the vertical direction. The rear vehicle body 8 is provided with a driver's cab 8b having a driver's seat 8a, and an engine compartment 8c that houses a power source such as an engine and a hydraulic power source behind the cab 8b.

Between each of the lift arms 10 and 10 and the front vehicle body 6, a pair of lift cylinders 12 and 12 for swinging the lift arms 10 and 10 are provided. The lift arms 10 and 10 are provided with a tilt lever 14 swingably at the center in the vehicle body width direction in the middle of the longitudinal direction. The tilt lever 14 is swung between one end of the tilt lever 14 and the front vehicle body 4. A tilt cylinder 16 is provided, and a tilt rod 18 is connected to the other end of the tilt lever 14.

A quick coupler 22 for detachably connecting a bucket 20 as a work tool is provided at the tip of the lift arms 10 and 10 and the tip of the tilt rod 18. The quick coupler 22 has a coupler body 24 connected to the lift arm arms 10 and 10 by pins 26 and 26 and to the tilt rod 18 by pins 28, respectively.

A description will be given with reference to FIG. 5 which is a side view of the bucket 20. The bucket 20 includes a pair of connecting plates 20a and 20a extending in the vertical direction at a predetermined interval in the left-right width direction (direction perpendicular to the paper surface of FIG. 5). A hook 20b for connecting to the coupler main body 24 is provided at the upper part of each of the connecting plates 20a, 20a, and an insertion hole 20c through which a fixing pin (the fixing pin will be described later) provided in the coupler main body 24 is inserted at the lower part. Is provided.

4 and FIG. 5, FIG. 1 is a front view of the quick coupler 22 as viewed from the driver's seat 8 a side of the wheel loader 2 (FIG. 4), and the operation lever and the locking when viewed from the side. The section will be described with reference to FIG. 2, which is a cross-sectional view of the coupler portion indicated by a solid line and a coupler body indicated by a two-dot chain line.

The quick coupler 22 includes a coupler main body 24 and a pair of right and left fixing pins 30 and 30 that are removably inserted into a bucket 20 provided and connected to the coupler main body 24 and releasably fix the coupling state of the coupler main body 24 and the bucket 20. The fixed pins 30 and 30 are connected to each other through the link mechanism 36, and the fixed pins 30 and 30 are inserted into the insertion holes 20c (FIG. 5) of the bucket 20 and the “release” is extracted. The operation lever 32 provided in the coupler main body 24 operated to the “position” and the one fixing pin 30 (left side in FIG. 2) are releasably engaged, and the fixing pin 30 is moved from the “fixed position” to the “release position”. Is provided with a locking means 34 for releasably locking the movement in the direction (arrow Z2 direction).

The coupler body 24 is formed substantially symmetrically in the left-right width direction (left-right direction in FIG. 1). A connecting pin 28 for connecting to the tilt rod 18 is provided at the center in the left and right and up and down directions, and connecting pins 26 and 26 for connecting to the lift arms 10 and 10 are provided in a detachable manner at the left and right side lower portions.

A pair of connection plates 20a, 20a provided in the bucket 20 described above is positioned between the connection pin 28 and the connection pins 26, 26 in the left-right width direction, and a pair of plates 24a ( Hitch portions 24c and 24c are provided with outer sides and 24b (inner sides) installed at predetermined intervals.

The space | interval of the width direction of a pair of plate 24a, 24b is formed in the magnitude | size in which the connection plate 20a of the bucket 20 can be positioned freely between them. A hitch 24d on which the hook 20b of the connecting plate 20a is hooked is provided at the upper part between the pair of plates 24a and 24b, and insertion holes 24e and 24f of the fixing pin 30 are provided at the lower part of the pair of plates 24a and 24b. It has been.

The operation lever 32 is located on the left hitch portion 24c, and extends in a pivotable manner about an axis X1 extending in the left-right width direction of the coupler main body 24, one end of the shaft 32a, and the plate 24a of the hitch portion 24c. A lever 32b that is integrally attached to the outer portion and extends in a strip shape upward is provided.

The link mechanism 36 includes a lever 36a that is integrally attached to the other end of the shaft 32a of the operation lever 32 and extends radially outward from the axis X1, and an axis X2 at the substantially central lower portion of the coupler main body 24 in the left-right width direction. A cross lever 36b that is pivotally attached to the center, a rod 36c that connects the cross lever 36b and the lever 36a, and a pair of links 36d and 36e that connect the cross lever 36b and the pair of fixing pins 30, 30 respectively. Yes.

The fixing pin 30 is moved in the direction indicated by the arrow Z1 in the width direction of the coupler main body 24 through the link mechanism 36 by the operation of the operation lever 32 and is inserted into the insertion hole 20c of the bucket 20 (fixed position) ( 1) and the “release position” that is moved in the direction indicated by the arrow Z2 and extracted from the insertion hole 20c.

The pair of fixing pins 30 and 30 are urged by a spring 37 connected to the cross lever 36b in the direction of “fixed position” in the “fixed position” and in the direction of “release position” in the “release position”. Yes.

The locking means 34 will be described with reference to FIG. 3 which is an enlarged detailed view together with FIGS. 1 and 2, mainly with reference to FIG. 3. The locking means 34 has a locking groove 34a formed in a rectangular cross section having a predetermined width W in the direction perpendicular to the axis X3 of the fixing pin 30 on the outer peripheral portion of the fixing pin 30, and is freely releasable in the locking groove 34a. An engaging plate 34b is provided near the fixing pin 30 insertion hole 24f of the coupler main body 24 to be engaged, and is attached so as to be swingable in a direction orthogonal to the axis X3. The rocking center X4 of the locking plate 34b is positioned above the insertion hole 24f.

When the fixing pin 30 is completely positioned at the “fixed position” (the state indicated by the solid line in FIG. 3), the locking groove 34a is connected to the end portion of the fixing pin 30 that protrudes from the insertion hole 24f, as shown in FIG. It is formed adjacent to the end face of the boss 31 of the insertion hole 24f at the end to which 1) is connected.

The locking plate 34b is formed of a plate material having a thickness that can be freely inserted into and removed from the locking groove 34a, and has an arcuate portion with a radius R that is a dimension from the swing center X4 to the groove bottom of the locking groove 34a. have. Retaining plate 34 b is in about the swing center X4, a bracket 34c that is integrally attached to the outer periphery of the boss 31 formed in the insertion hole 24f, it is attached by rivets 34d.

On the surface of the bracket 34c side of the lower portion of the retaining plate 34 b, handle 34e bent round bar into an L-shape, it is provided with integrally attached to one end thereof. The handle 34e extends from the locking plate 34d to the vicinity of the plate 24b of the hitch portion 24c.

FIG. 3 shows a locked state in which the locking plate 34b of the locking means 34 is engaged with the locking groove 34a of the fixed pin 30 and the fixed pin 30 cannot move from the “fixed position” to the “release position”. ing. Therefore, the fixing pin 30 cannot be moved by operating the operation lever 32. In order to move the fixing pin 30 from the “fixed position” to the “released position” by operating the operation lever 32, the locking plate 34b is moved in the clockwise direction indicated by the arrow S by using the handle 34e. It is swung to disengage the engaging groove 34a from the engaging plate 34b (indicated by a two-dot chain line).

The operation and effect of the quick coupler 22 of the work vehicle as described above will be described.

The quick coupler 22 of the work vehicle configured according to the present invention is releasably engaged with a fixing pin 30 that connects the coupler body 24 and the bucket (working tool) 20, and the fixing pin 30 is inserted into the bucket 20. A locking means 34 is provided for releasably locking in the “position” state.

Therefore, since the fixing pin 30 is locked in the “fixed position” state by the locking means 34, the fixing pin 30 is held in the “fixed position” even if the operation lever 32 interferes with an obstacle or the like. Further, since the fixing pin 30 is locked at the “fixed position” by the locking means 34, the trouble that the operator has to visually recognize the insertion state of the fixing pin 30 is also eliminated.

The locking means 34 includes a locking groove 34a formed on the outer peripheral portion of the fixing pin 30 in a direction perpendicular to the axis X3 of the fixing pin 30, and a coupler body 24 that is detachably engaged with the locking groove 34a. A locking plate 34b is provided in the vicinity of the insertion hole 24f of the fixing pin 30 so as to be swingable in a direction orthogonal to the axis X3.

Therefore, the fixing pin 30 can be easily fixed and held easily and released by the locking groove 34a and the locking plate 34b that are releasably engaged.

The rocking center X4 of the locking plate 34b is located above the insertion hole 24f of the fixing pin 30.

Therefore, when the fixing pin 30 is fixed and held in the “fixed position” state by the locking plate 34b, the locking state of the locking plate 34b and the locking groove 34a is more reliably held by the own weight of the locking plate 34b. Is done.

The front view which looked at the quick coupler of the work vehicle comprised according to this invention from the driver's seat side of the work vehicle (it looked at the CC arrow direction of FIG. 4). FIG. 2 is a cross-sectional view of the coupler main body indicated by a two-dot chain line and the operation lever and the locking means indicated by a solid line when viewed in the direction of arrows AA in FIG. (A) An enlarged detail view of the portion of the locking means in FIG. 1, (b) a view of FIG. 3 (a) in the direction of arrow BB. The side view of the wheel loader as a working vehicle equipped with the bucket as a working tool connected with the quick coupler and quick coupler comprised according to this invention. The side view of the bucket single-piece | unit of FIG.

Explanation of symbols

2: Wheel loader (work vehicle)
10: Lift arm (working arm)
20: Bucket (work implement)
22: Quick coupler 24: Coupler body 30: Fixing pin 32: Operation lever 34: Locking means 34a: Locking groove 34b: Locking plate X3: Fixing pin axis X4: Center of swinging of the locking plate

Claims (1)

A coupler body that is mounted on a work arm of a work vehicle and removably connects a work tool,
A fixing pin that is provided in the coupler body and is removably inserted into the work tool, and the connection state between the coupler body and the work tool is releasably fixed,
An operation lever that is connected to the fixing pin via a link mechanism and operates to a “fixed position” in which the fixing pin is inserted into the work tool and a “release position” that is extracted from the work tool,
A spring provided in the link mechanism for biasing the fixing pin in the “fixed position” direction in the “fixed position” direction and in the “release position” direction in the “release position”;
Engaging with the fixing pin releasably, and having a locking means for releasably locking the movement of the fixing pin in the direction from the “fixed position” to the “release position” ,
The locking means
A locking groove formed in the direction perpendicular to the axis of the fixing pin on the outer periphery of the fixing pin;
A locking plate that is detachably engaged with the locking groove and is mounted in the vicinity of the fixed pin insertion hole of the coupler main body so as to be swingable in a direction orthogonal to the axis, with the upper part of the insertion hole as a swing center. And
Quick coupler for a working vehicle engagement of the locking plate and the locking groove is Ru is held by the weight of the locking plate, it is characterized.

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