JPH0660498B2 - Front loader desorption device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an attachment / detachment device for a front loader detachably attached to a tractor.

(Prior Art) Various front-mounted work machines are detachably attached to a tractor and used for various work. As this front-loading work machine, for example, a front loader having a bucket or a scraper at its front part for transferring earth and sand is known. Since the front loader is detachably attached to the tractor, it is desirable that the front loader can be easily attached and detached. Further, since heavy work is performed, the structure must have high rigidity and be firmly attached in the mounted state. Furthermore, since it is stored in a detached state, the structure must be easy to store.

To meet these requirements, for example
The one described in JP-A-160349 is known.

As shown in FIG. 8, this conventional front loader includes a mast 50, a boom 51 pivotally supported on the upper end of the mast 50 so as to project forward, and a bucket 52 pivotally supported on the front end of the boom 51.
A boom cylinder 53 interposed between the mast 50 and the boom 51 to rotate the boom 51 in the vertical direction; and a bucket cylinder 54 interposed between the bucket 52 and the boom 51 to rotate the bucket 52 in the vertical direction. And a brace 55 fixed to the mast 50 so as to project forward.

In this front loader, the lower end of the mast 50 is detachably attached to the mast receivers 57 provided on both left and right sides of the tractor vehicle body 56 in the middle of the front-rear direction, and the front portion of the brace 55 is attached to the vehicle body. It is detachably attached to a fixed portion 58 provided on the front portion of 56 and is attached to the tractor vehicle body 56.

The front loader has braces to facilitate storage.
The front portion of 55 is configured as a stand portion 59. That is, when detached from the tractor and stored, the lower surface of the bucket 52 and the lower end of the stand portion 59 are grounded so that the assembled state can be maintained and the standing state can be stably maintained.

Further, the front loader is provided with a locking pin 60 at the lower end of the mast 50 to facilitate the attachment / detachment operation.
While the beak-shaped engaging groove 61 is provided in 57, the stand portion 59 is provided with a pin hole 62 for engaging with the fixing portion 58, and in order to align the pin hole 62 with the fixing portion 58, a stand is provided. A guide portion 63 for guiding the portion 59 is provided.

That is, in the mounting work of the front loader, as shown in FIG. 9, the locking pin 60 at the lower part of the mast 50 is placed at the entrance of the locking groove 61 of the mast receiver 57, and from this state, the boom cylinder 53
And the guide portion 63 is fixed in the direction of the arrow a of the stand portion 59.
The pin hole 62 and the fixing portion 58 are aligned with each other by being guided by 58, and the locking pin 60 is slid in the locking groove 61 in the rearward b direction and is stored in the fixed position at the back. And then the pin hole
The front portion of the brace 55 is fixed to the vehicle body 56 by inserting the pin into the fixing portion 58 by inserting a pin into the 62, and the locking pin 60 of the mast 50 is fixed to the locking groove 61. It is located at the back and is prevented from moving upward and is fixed to the mast receiver 57.

Further, as an attachment / detachment device for this type of front loader, there are those described in Japanese Utility Model Laid-Open No. 59-43560 and Japanese Utility Model Laid-Open No. 59-84058.

(Problems to be Solved by the Invention) In the conventional device shown in FIGS. 8 to 9, the locking pin 60 is slid into the beak-shaped locking groove 61 of the mast receiver 57 during mounting. Therefore, in order to slide the locking pin 60, a long guide portion 63 is required in the stand portion 59, and the relative positional relationship between the guide portion 63 and the locking groove 61 is required to be highly accurate. The production cost was high.

Further, in the mounted state, the mast 50 and the mast receiver 57 are
Since it is fixed by fitting the locking pin 60 and the locking groove 61, there is a problem in that it is inferior in rigidity and loose.

Further, in the one disclosed in Japanese Utility Model Laid-Open No. 59-43560, since the pin which is cantilevered by the mast receiver is engaged with the concave portion at the lower end of the mast, the coupling strength thereof is weak. It was Furthermore, the pin and the recess are engaged with each other with a play in the front-rear direction, and the upward movement preventing part provided by the recess and the pin provided thereabove is movable in the front-rear direction. The joint rigidity of the mast receiver in the front-rear direction was low and it was rattling.

Further, in the one disclosed in Japanese Utility Model Laid-Open No. 59-84058, similarly to the above, there is play in the front-rear direction in the engaging portion between the pin and the recessed portion, so that the upward movement preventing portion provided above the engaging portion has two The pin was used to prevent the backlash. Therefore, it is necessary to position the two pin holes and insert the pins, the pin hole positioning accuracy is required, and the work of inserting and removing the two pins is troublesome.

Further, in each of the above-mentioned conventional ones, the mast has to be moved back and forth and up and down in the mounting work, which makes it difficult to perform the detaching operation.

In view of the above problems, the present invention provides a front loader attachment / detachment device that does not require strict manufacturing accuracy, has a simple structure, is easy to attach / detach, and enables rigid body coupling. With the goal.

(Means for Solving the Problems) A feature of the present invention for achieving the above-mentioned object is that a mast receiver fixed to a lateral side portion of a front-rear midway portion of a tractor vehicle body and a mast of a front loader. In the attachment / detachment device of the front loader that detachably connects
The mast receiver includes a pair of left and right side walls, a columnar body bridged between the side walls, and a single lock penetrating both side walls above the columnar body with a horizontal axis. The mast has a pin hole, and the mast is formed on the lower surface side of the skirt so that the mast can be fitted vertically to the left and right sides of the lower end of the mast from the upper side without rattling in the front-rear direction. And an arcuate recess that matches the shape of the cylindrical body,
And one pin hole formed at a position that matches the lock pin hole when the mast is fitted to the cylindrical body from above without rattling in the front-rear direction and the mast is erected on the mast receiver. The lower surface of the skirt portion is formed into a V-shaped guide surface that guides the columnar body toward the recess, and the distance between the lower end of the guide surface and the center of the pin hole is the arc shape. It is set to be larger than the distance from the point where the line connecting the arc center of the recess and the center of the pin hole and the arc surface of the recess intersects to the center of the pin hole, and locks on both the matched pin holes. The point is that the pin is inserted and removed freely.

(Operation) According to the present invention, when the mast is attached to the mast receiver, the mast is lowered with respect to the mast receiver. Then,
The guide surface on the lower surface of the skirt portion provided at the lower end of the mast descends while slidingly contacting the cylindrical body of the mast receiver, and the cylindrical body automatically fits into the recess provided on the lower surface of the skirt portion. When the mast is made vertical in this state, the pin holes provided in both the mast receiver and the mast are aligned, so the lock pin is inserted into both pin holes.

The recess and the cylindrical body are fitted together without rattling in the front-rear direction,
Further, the distance from the lower end of the guide surface to the center of the pin hole is from the point where the line connecting the arc center of the arc-shaped recess and the pin hole center and the arc surface of the recess intersect to the pin hole center. Since it is set to be larger than the distance, the mast receiver and the mast can be connected without rattling only by inserting one lock pin.

(Example) Hereinafter, the Example of this invention is described based on drawing.

In FIGS. 3 to 4, reference numeral 1 denotes a tractor vehicle body, and a front loader 2 is detachably attached to the tractor vehicle body 1.

The tractor body 1 is configured by rigidly connecting the front axle frame 3, the engine 4, the transmission case 5, and the like, and the engine 4 is covered with a hood 6. The tractor body 1 is supported by front wheels 7 and rear wheels 8, and the rear wheels 8 are supported by rear axle cases 9 protruding from both left and right sides of the mission case 5.

The mast receiving brackets 10 are bolted outwardly on both sides in the left-right direction in the front-rear direction of the tractor body 1.
It is fixed at 11 (see Figures 5 and 6). The bracket 10 and the rear axle case 9 are connected and fixed by a rear connecting member 12. Further, the bracket 10 and the front axle frame 3 are connected and fixed by a front connecting member 13.

The front connecting member 13 includes a first member 15 extending from the bracket 10 upward and upward to bypass the muffler 14, and the first member 15.
A second member 16 horizontally extending forward from the front end of the member 15 through the inside and above the front wheel 7, a third member 17 extending below the front end of the second member 16, and a lower end of the third member 17. And a fourth member 18 fixed to the front surface of the front axle frame 3. A boss 20 having a pin insertion hole 19 having a lateral axis in the left-right direction is fixed to the fourth member 18, and a fixing portion 21 is formed. (See FIGS. 2, 4, 5, and 7).

A mast receiver 22 is fixed to the outer end portion of the mast receiving bracket 10. As shown in FIGS. 1, 5, and 6, the mast receiver 22 is formed by the left and right side walls 23 and the rear wall 24 and has a U-shaped cross section with front and upper openings. A cylindrical body 25 having a horizontal axis in the left-right direction is provided in the opening of the mast receiver 22. The columnar body 25 is installed between the left and right side walls 23.

The columnar body 25 is provided in front of the rear wall 24 as far as possible.

A lock pin hole 26 penetrating in the left-right direction is formed in the left and right side walls 23 above the columnar body 25.

The front loader 2 has a mast 27 that is detachably provided on the mast receiver 22. The width of the mast 27 is set to fit within the opening of the mast receiver 22,
A bottom wall 27a is provided on the lower end surface thereof, and skirt portions 27b are vertically provided on both left and right sides of the bottom wall 27a. In this skirt portion 27b, a concave portion 28 that fits into the cylindrical body 25 is formed,
The recess 28 is formed when the columnar body 25 is fitted.
25 has a depth such that it abuts the bottom wall 27a, and the cylindrical body 2
It is sized to fit 5 without play in the front-back direction.
That is, the recess 28 is formed in an arc shape that matches the shape of the cylindrical body 25, and can be fitted from above the cylindrical body 25. The lower end surface of the skirt portion 27b serves as a guide surface 29 that is connected to the recess 28. This guide surface 29 is a cylindrical body when the mast 27 is fitted into the mast receiver 22 from above.
The lower end of the mast 27 is formed in a shape that guides the lower end of the mast 27 so that the recess 28 fits into the columnar body 25 while coming into contact with the lower end 25. That is, the guide surface 29 is formed in a V shape inclined toward the concave portion 28 side, and the rear end surface of the lower end of the skirt portion 27b is formed into the curved surface portion 30 and the curved surface portion 30 and the mast receiving portion. The rear wall 24 of 22 is configured to smoothly abut.

The mast 27 is provided with a pin hole 26a that matches the lock pin hole 26 of the mast receiver 22 when the recess 28 is fitted into the columnar body 25 and is erected. Then, the stopper pin 26b is inserted into both the matched pin holes 26, 26a. Then, the stopper device 2 is formed by the pin 26b and the pin holes 26, 26a.
6c is constructed. The distance from the lower end position of the curved surface portion 30 to the center of the pin hole 26a is a point where the line connecting the arc center of the arc-shaped recess 28 and the center of the pin hole 26a intersects the arc surface of the recess 28. To a center of the pin hole 26a.

A boom 31 projecting forward is pivotally supported at the upper end of the mast 27, and a work implement 32 such as a bucket or scraper is pivotally supported at the front end of the boom 31. Between the boom 31 and the mast 27, the boom 31 is rotated about the horizontal axis of the left-right direction via the pivotal support.
A drive means 33 for moving up and down is provided. The drive means 33 is composed of a hydraulic cylinder that connects the midway portion of the boom 31 and the midway portion of the mast 27. A hydraulic cylinder 34 for rotating the work implement is also interposed between the boom 31 and the work implement 32, and the work implement 32 is also rotated about the horizontal axis in the left-right direction by the expansion and contraction operation of the hydraulic cylinder 34.

A brace projecting forward from the mast 27 in the middle of the vertical direction.
35 is fixed. A stand portion 36 extending downward is formed on the front portion of the brace 35. A ground plate 37 capable of grounding to the ground is fixed to the lower end of the stand portion 36. A bracket 38 having a U-shaped cross section having a rear opening and an upper opening as shown in FIGS. 2, 5, and 7 is fixed to the inner surface of the lower portion of the stand portion 36, and a stopper plate is provided below the opening. It is swiveled at 39. The opening width of the bracket 38 is dimensioned to receive the boss portion 20 of the fixing portion 21. The bracket 38 and the stand portion 36 are provided with pin holes 40 penetrating in the left-right direction. The pin hole 40 coincides with the pin insertion hole 19 of the fixed protrusion 21 so that the fixed pin 41 can be inserted and removed.

Reference numeral 42 is a hydraulic control box for operating the drive means 33 and the hydraulic cylinder 34, to which a hydraulic pipe from the tractor vehicle body 1 side is detachably connected.

According to the embodiment of the present invention having the above-described structure, the front loader 2 is in a state shown by phantom lines in FIGS. 1 and 2 and a state shown in FIG.
Is removed from the tractor body 1 and is held upright. From the state shown in FIG. 4, in order to mount the front loader 2 on the tractor vehicle body 1, the tractor is moved forward to move the mast 27.
The lower end of is positioned within the opening of the mast receiver 22. After that, the control box 42 and the hydraulic pipe on the vehicle body side are connected to reduce the hydraulic cylinder of the drive means 33. As a result, the curved surface portion 30 at the lower end of the mast 27 comes down while coming into contact with the rear wall 24 of the mast receiver 22, and the columnar body 25 comes into contact with the guide surface 29 and slides, so that the concave portion 28 at the lower end of the mast 27 is formed. It fits into the cylindrical body 25.

By further reducing the cylinder of the drive means 33, the mast 27 rotates around the columnar body 25, and the brace 35
Moves upward, the bracket 38 is fitted into the boss portion 20 of the fixed portion 21, and the stop plate 39 on the lower surface thereof abuts the boss portion 20 to stop the upward rotation of the brace 35. In this state, the pin insertion hole 19 of the fixed portion 21 and the pin hole 40 of the stand portion 36
Therefore, the brace 35 is fixed to the vehicle body 1 side by inserting the fixing pin 41 into both pin holes 19 and 40. In this state, the mast 27 is erected on the mast receiver 22, and the lock pin hole 26 and the pin hole 26a of the mast 27 are aligned, so that the stopper pin 26b is inserted into both holes 26, 26a, and the mast 27 and the mast receiver Fix 22.

Therefore, in the above-described embodiment, the columnar body 25 and the recess 28 are fitted together without rattling in the front-rear direction, and the distance between the center of the stopper pin 26b and the lower end of the skirt portion 27b is determined by the stopper pin 2.
Since it is larger than the distance from the center of 6b to the cylindrical body 25, the mast 27 is self-supported by the one stopper pin 26b.

The present invention is not limited to the above embodiment.

(Effect of the invention) According to the present invention, the mast receiver and the mast can be joined by simply lowering the mast, so that the detaching work is simple and the joining state of the mast and the mast is loose by one lock pin. It can be maintained without using the structure, and the structure is simple and the rigidity is high.

[Brief description of drawings]

FIG. 1 is a partially enlarged cross-sectional view showing an essential part of an embodiment of the present invention,
FIG. 2 is an enlarged view showing the front part of the front loader, FIG. 3 is a side view showing the overall structure, FIG. 4 is a side view for explaining the operation, FIG. 5 is a plan view of the front loader, and FIG. 5 is a sectional view taken along line VI-VI in FIG. 5, FIG. 7 is a front view thereof, FIG. 8 is a side view of a conventional example, and FIG. 1 ... Tractor body, 2 ... Front loader, 22 ... Mast receiver, 23 ... Side wall, 25 ... Cylindrical body, 26 ... Lock pin hole, 26a ... Pin hole, 26b ... Lock pin, 27 ... … Mast, 27b …… Skirt, 28 …… Concave, 29 …… Guide surface.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Shozo Hirooka 64 Ishizukita-machi, Sakai City, Osaka Prefecture Kubota Iron Works Co., Ltd.Sakai Works Sakai Factory (56) References: Actual Development Sho 59-43560 (JP, U) Japanese Patent Sho 59-84058 (JP, B1)

Claims (1)

[Claims] 1. A front loader attaching / detaching device for detachably connecting a mast receiver (22) fixed to a lateral side portion of a tractor vehicle body (1) in the front-rear midway portion and a mast (27) of a front loader. The mast receiver (22) includes a pair of left and right side walls (23) and the side walls (23).
A columnar body (25) installed between (23), and one lock pin penetratingly provided on both side walls (23) above the columnar body (25) with a horizontal axis. The mast (27) has a hole (26), and the mast (27) is fitted into the columnar body (25) from above without skirting (27b) vertically extending to the left and right sides of the lower end. An arcuate concave portion (28) formed on the lower surface side of the skirt portion (27b) to match the shape of the cylindrical body (25), and the concave portion (28) in front of and behind the cylindrical body (25). When the mast (27) is erected on the mast receiver (22) by fitting from above without rattling in the direction, the lock pin hole
(26) has a single pin hole (26a) opened at a position corresponding to (26), and the lower surface of the skirt portion (27b) guides the columnar body (25) toward the recess (28). It is formed on a V-shaped guide surface (29), and the distance between the lower end of the guide surface (29) and the center of the pin hole (26a) is the arc center of the arc-shaped recess (28) and the pin hole ( 2
6a) is set to be larger than the distance from the point where the line connecting the center and the arc surface of the recess (28) to the center of the pin hole (26a), and the both pin holes (26 ) (26a) has a lock pin (26b) removably inserted therein, which is a front loader attaching / detaching device.