Patent Description:
The device disclosed in Patent Document <NUM> is known as a working machine coupler device for coupling a working machine to a traveling vehicle (tractor).

The working machine coupler device disclosed in Patent Document <NUM> includes a three-point linkage mechanism. The three-point linkage mechanism includes a top linkage and a lower linkage pivotally connected to the rear portion of the tractor. The rear portion of the top linkage and the lower linkage are connected by a detachable frame. The working machine includes a first upper coupler portion and a first lower coupler portion. The detachable frame is provided with a second upper coupler portion that engages the first upper coupler portion and a second lower coupler portion that engages the first lower coupler portion.

To couple the working machine to the tractor, the second upper coupler portion is positioned below the first upper coupler portion, and the second upper coupler portion is engaged with the first upper coupler portion by lifting the lower linkage from this state. Then, when the lower linkage is lifted further, the working machine is lifted up and pivoted forward around the first upper coupler portion. When the working machine pivots forward, the first lower linkage is automatically coupled close to the second lower linkage. In this manner, the working machine is coupled to the tractor.

In the working machine coupler device, it is necessary for coupling the working machine to position the second upper coupler portion below the first upper coupler portion. For this reason, the working machine can be tilted forward with respect to a working posture, and thereby the second upper coupler portion can be positioned below the first upper coupler portion. However, depending on a type of the working machine, a stand may be necessary to maintain the forward tilting posture. When a stand is required to maintain the posture during attachment and detachment, the stand requires a large size deteriorating workability, which is impractical, when the working machine is a large implement such as a rear-mounted mower.

In view of the problems mentioned above, the present invention is intended to provide a working machine coupler device that enables a working machine to be coupled to a traveling vehicle without having to tilt the working machine.

The claimed invention is defined by the features set forth in the appended independent claims. Particular embodiments of the claimed invention are defined by the dependent claims.

According to the present invention, it is possible to couple a working machine to a raveling device without inclining the working machine.

Hereinafter, an embodiment of the present invention will be described with appropriate reference to the drawings.

<FIG> is a schematic side view of a working machine coupler device <NUM> according to this embodiment. The working machine coupler device <NUM> is a device for connecting a working machine <NUM> to a traveling vehicle <NUM>. In this embodiment, a tractor is illustrated as the traveling vehicle <NUM>. The traveling vehicle is hereafter referred to as the tractor <NUM>. A rear-mounted mower (rear cutter) or other ground working machine is exemplified as the working machine <NUM>.

In this embodiment, a direction of an arrowed line A1 direction in <FIG> (a forward direction of the tractor <NUM>) is referred to as the front, and a direction of an arrowed line A2 in <FIG> (a backward direction of the tractor <NUM>) is referred to as the rear. Thus, the front surface side of <FIG> is referred to the left, and the back surface side of <FIG> is referred to the right. The horizontal direction orthogonal to the front-to-rear direction A3 is explained as a vehicle width direction. The direction from the center to the right or left portion of the vehicle width direction in tractor <NUM> is explained as the outside of the vehicle (also referred to as a vehicle outward direction). In other words, the vehicle outward direction is the direction in the vehicle width direction separating away from the center of the tractor <NUM>. A direction opposite to the vehicle outward direction is explained as a vehicle inward direction (also referred to as a vehicle inward direction). In other words, the vehicle inward direction is the direction in the vehicle width direction approaching closer to the center of the tractor <NUM>.

As shown in <FIG>, the tractor <NUM> includes a vehicle body <NUM>. The vehicle body <NUM> includes, for example, a prime mover as a power source, a flywheel housing that houses a flywheel, a clutch housing that houses a clutch for intermittently transmitting the power of the prime mover transmitted through the flywheel, and a transmission case that houses a transmission for shifting the power transmitted through the clutch, which are arranged and directly connected in a front-to-rear direction of the vehicle body. The prime mover is, for example, a diesel engine.

The tractor <NUM> includes an operator seat <NUM> and a hydraulic system <NUM> mounted on the rear portion of the vehicle body <NUM>. The hydraulic system <NUM> includes a left lift arm <NUM> arranged on the left side of the body 12A and a right lift arm 13R arranged on the right side of the body 12A. The lift arms <NUM> and 13R are attached to a rotation shaft <NUM> whose front portion includes a horizontal axial center (axial center extending in the vehicle width direction) and can be pivoted up and down by rotating the rotation shaft <NUM> around the axial center in the hydraulic driving. The upper portion of the left lift rod <NUM> is rotatably connected to the rear portion of the lift arm <NUM>, and the upper portion of the right lift rod 22R is rotatably connected to the rear portion of the lift arm 13R, which is rotatably connected to the rear portion of the lift arm 13R.

On the back of the vehicle body <NUM>, a PTO shaft <NUM> is provided; the PTO shaft <NUM> is a power take-out shaft that takes power from the prime mover externally; the PTO shaft <NUM> is interlocked with the PIC shaft <NUM> of the working machine <NUM> via a drive shaft <NUM>. The drive shaft <NUM>, for example, consists of a universal joint and includes a first universal joint 17A, a second universal joint 17B, and a joint shaft 17C. The first universal joint portion 17A is connected to the PTO shaft <NUM>. The second universal joint 17B is connected to the PIC axis <NUM>. The joint shaft 17C connects and interlock the first universal joint portion 17A and the second universal joint portion 17B. The joint shaft 17C is freely telescopic in length. The term "telescoping" means that it is free to stretch and shorten in length. The term "stretching" means that the length is increased, and the term "shortening" means that the length is reduced.

The rear portion of tractor <NUM> is provided with a top linkage bracket <NUM>, a left lower linkage bracket <NUM> and a right lower linkage bracket 24R. The top linkage bracket <NUM> is fixed to the upper rear portion of the vehicle body <NUM>. The lower linkage bracket <NUM> is fixed to the left rear bottom of the vehicle body <NUM>. The lower linkage bracket R is fixed to the right rear bottom of the vehicle body <NUM>.

The PIC shaft <NUM> is an input shaft for inputting power transmitted from the tractor <NUM> through the drive shaft <NUM> to the working machine <NUM>. The power transmitted to the PIC shaft <NUM> is input to the transmission mechanism in the transmission case <NUM> through the transmission shaft <NUM>. The power transmitted to the transmission mechanism in the transmission case <NUM> is transmitted to a ground working device provided in the cover case <NUM>. The ground working device is, for example, a mower device including a mower blade (mowing blade) that mows the grass, a drive mechanism to drive the mower blade, and the like, as a rear-mounted mower.

As shown in <FIG>, the working machine <NUM> includes an attachment frame <NUM>. The attachment frame <NUM> includes a first frame member 25A and a second frame member 25B. The first frame member 25A is provided in an inclined manner that transitions upward from the cover case <NUM> toward the front. A first upper coupler portion <NUM> is provided in the front upper portion of the first frame member 25A. The first upper coupler portion <NUM> consists, for example, of a pin having a transverse axis center. A second frame member 25B is provided extending forward on the cover case <NUM>. A first lower coupler portion <NUM> and a first lower coupler portion 27R are provided at the front portion of the second frame member 25B. The first lower coupler portion <NUM> is located on the left side of the working machine <NUM>, and the first lower coupler portion 27R is located on the right side of the working machine <NUM>. The first lower coupler portion <NUM> and the first lower coupler portion 27R are formed of a pin with a transverse axis center, for example.

As shown in <FIG>, the working machine coupler device <NUM> includes a three-point linkage mechanism <NUM> attached to the rear portion of the tractor <NUM>. The three-point linkage mechanism <NUM> includes one top linkage <NUM> and two lower linkages <NUM> (lower linkage <NUM> and lower linkage 7R). The top linkage <NUM> is located in the center of the vehicle width direction of the vehicle body <NUM> and above the lower linkage <NUM> and the lower linkage 7R. The top linkage <NUM> includes a cylinder (first member) 6A and a rod member (second member) 6B. The front portion of the top linkage <NUM> (cylinder 6A) is rotatably connected to the top linkage bracket <NUM> via a pivot axis <NUM> to rotate freely around the horizontal axis center. The rod member 6B is inserted into the cylinder 6A freely in and out of the rear portion. The rod member 6B is movable in the longitudinal direction of the top linkage <NUM>. That is, the top linkage <NUM> is stretchable in length.

The top linkage <NUM> may be configured such that the rod member 6B is located to the front and the cylinder 6A is located to the rear. In this case, the rod member 6B is pivoted to the top linkage bracket <NUM> and the cylinder 6A is pivoted to the detachable frame <NUM> described below.

The lower linkage <NUM> is rotatably connected at the front to the left lower linkage bracket <NUM> via a pivot axis <NUM> around the transverse axis center. The lower portion of the left lift arm <NUM> is pivotally connected to the middle portion of the lower linkage <NUM> in the longitudinal direction. The front portion of the lower linkage 7R is rotatably connected to the right lower linkage bracket 24R via a pivot axis <NUM> to the right lower linkage bracket 24R, which is rotatably connected around the horizontal axis center. The lower portion of the right lift arm 13R is pivotally connected to the middle of the lower linkage 7R in the longitudinal direction. Thus, the lower linkage <NUM> and the lower linkage 7R can be raised and lowered (pivoted up and down) by pivoting the lift arm <NUM> and the lift arm 13R up and down by the pivoting axis <NUM>.

The rear portion of the top linkage <NUM> and the rear portion of the lower linkages <NUM> and 7R are connected by the detachable frame <NUM>. The rear portion of the top linkage <NUM> (rod member 6B) is rotatably connected to the upper portion of the detachable frame <NUM> via a pivot axis <NUM>, which is rotatable around the horizontal axis center. The rear portion of the lower linkage <NUM> is rotatably connected to the lower and left side of the detachable frame <NUM> via the pivot axis <NUM> in the transverse axis. The rear portion of the lower linkage 7R is rotatably coupled at the bottom and on the right side of the detachable frame <NUM> via the pivot axis <NUM> in the lower portion of the detachable frame <NUM> and rotatably around the transverse axis.

In the following description, the lower linkage <NUM> and the lower linkage 7R may be collectively referred to as the lower linkage <NUM>.

On the upper portion of the detachable frame <NUM>, a second upper coupler portion <NUM> is provided which engages the first upper coupler portion <NUM>. The second upper coupler portion <NUM> includes a groove which opens upwardly and allows the first upper coupler portion <NUM> to be inserted, and is formed in the form of a hook. Thus, the second upper coupler portion <NUM> can be engaged with the first upper coupler portion <NUM> from below. The working machine <NUM> can be rotated around the first upper coupler portion <NUM> with the second upper coupler portion <NUM> engaged with the first upper coupler portion <NUM>. In other words, the working machine <NUM> is pivotable in the direction of proximity and detachment with respect to the detachable frame <NUM> with the second upper coupler portion <NUM> engaged with the first upper coupler portion <NUM>.

The lower portion of the detachable frame <NUM> is provided with a second lower coupler portion <NUM> that engages the first lower coupler portion <NUM> and the second lower coupler portion 34R that engages the first lower coupler portion 27R. The second lower coupler portion <NUM> includes a groove that is open toward the rear and into which the first lower coupler portion <NUM> can be inserted. The first lower coupler portion <NUM> can engage with the second lower coupler portion <NUM> when the working machine <NUM> is pivoted around the first upper coupler portion <NUM> in a direction approaching close to the detachable frame <NUM>. The second lower coupler portion 34R includes a groove that opens backward and allows the first lower coupler portion 27R to be inserted thereto. The first lower coupler portion 27R can engage with the second lower coupler portion 34R when the working machine <NUM> pivots around the first upper coupler portion <NUM> in a direction approaching close to the detachable frame <NUM>. The second lower coupler portion <NUM> is provided with a locking mechanism (not shown in the drawings) that regulates the first lower coupler portion <NUM> to be detached from the second lower coupler portion <NUM>. The second lower coupler portion 34R is also provided with a locking mechanism (figure omitted) that regulates detachment of the first lower coupler portion 27R from the second lower coupler portion 34R.

In the following description, the first lower coupler portion <NUM> and the first lower coupler portion 27R are collectively referred to as the first lower coupler portion <NUM>, and the second lower coupler portion <NUM> and the second lower coupler portion 34R may be collectively referred to as the second lower coupler portion <NUM>.

At the middle portion of the detachable frame <NUM> in the vertical direction, the second universal joint portion 17B of the drive shaft <NUM> is pivotally supported up and down (pivotable). This allows the PIC shaft <NUM> to automatically couple to the second universal joint 17B when the working machine <NUM> is pivoted in a direction proximate to the detachable frame <NUM> around the first upper coupler portion <NUM>.

As shown in <FIG>, the working machine <NUM> includes a top linkage controller mechanism <NUM> that controls the stretching and shortening of the top linkage <NUM>.

As shown in <FIG>, the top linkage controller mechanism <NUM> includes a plate member <NUM>, an engagement member (engagement pin) <NUM>, and a switching mechanism <NUM>.

As shown in <FIG>, the plate member <NUM> is formed of a plate material long in the length direction of the top linkage <NUM> and is arranged above the top linkage <NUM>. The plate member <NUM> is arranged over the cylinder 6A from the rod member 6B, and one end side (rear) is attached to the rod member 6B by the support member <NUM>. Thus, the plate member <NUM> moves in synchronization with the rod member 6B. The plate member <NUM> includes an engagement groove <NUM> with which the engagement member <NUM> engages. The engagement groove <NUM> is formed in the front portion of the plate member <NUM>. The engagement groove <NUM> is a groove formed through the plate member <NUM> and is formed in a long groove elongated in the length direction of the top linkage <NUM>.

As shown in <FIG>, the engagement groove <NUM> includes a first groove portion 41a, a second groove portion 41b, and a lock portion (locking hole) 41c. The first groove portion 41a includes the front portion of the engagement groove <NUM> and is formed into a long groove in the longitudinal direction of the plate member <NUM>. The second groove 41b includes the middle portion of the engagement groove <NUM> and is formed in a long groove in the longitudinal direction of the plate member <NUM>. The second groove portion 41b is formed continuously with the first groove portion 41a. The lock portion 41c includes a rear portion of the engagement groove <NUM> and is formed to be a circular hole. The lock portion 41c is formed in continuity with the second groove portion 41b. The second groove portion 41b and the lock portion 41c include a floating portion <NUM>.

As shown in <FIG>, the second groove portion 41b has a wider groove width than the first groove portion 41a. In other words, the groove width W1 of the first groove portion 41a is narrower than the groove width W2 of the second groove portion 41b. The lock portion 41c is formed to be a hole of diameter W3, which is larger than the groove width W2 of the second groove portion 41b.

As shown in <FIG>, the engagement member <NUM> is formed of a stepped pin having a plurality of sites of different diameters. In detail, the engagement member <NUM> includes a first portion 38a in the upper portion, a second portion (semi-locking engagement portion) 38b in the middle of the vertical direction, and a third portion (locking engagement portion) 38c in the lower portion. The first portions 38a, second portions 38b and third portions 38c are formed in a cylindrical and concentric shape. The second portion 38b is formed to have a larger diameter than the first portion 38a, and the third portion 38c is formed to have a larger diameter than the second portion 38b.

As shown in <FIG>, the engagement member <NUM> is located on the lower side of the engagement groove <NUM> and is supported by the switching mechanism <NUM> such that a vertical position is changeable (changeable in the direction of proximity and separation from the engagement groove <NUM>). In detail, the switching mechanism <NUM> supports the engagement member <NUM> to be movable between a position where the first portion 38a can be inserted into the engagement groove <NUM> (first groove 41a) (see <FIG>), a position where the second portion 38b can be inserted into the engagement groove <NUM> (second groove 41b) (see <FIG>), and a position where the first portion 38c can be inserted into the engagement groove <NUM> (lock portion 41c) (see <FIG>).

As shown in <FIG>, the diameter D1 of the first portion 38a is formed in a dimension roughly equal to the groove width W1 of the first groove 41a. The first portion 38a is insertable into the first groove 41a and can move along the longitudinal direction in the first groove 41a, relative to the first groove 41a. Thus, the first portion 38a is able to move between the front end and the rear end of the engagement groove <NUM> relative to the engagement groove <NUM>. In detail, the first portion 38a is movable relative to the engagement groove <NUM> in an area (first range) E1 between the first regulator portion 41d that is the end (front end) of the first groove 41a and the rear end of the lock portion 41c. In other words, the top linkage <NUM> is extendable and retractable to the extent that the first region 38a moves relative to the first range E1 in a state where the first region 38a is located in the engagement groove <NUM>.

As shown in <FIG>, the diameter D2 of the second portion 38b is formed to have a dimension roughly equal to the groove width W2 of the second groove 41b. The second portion 38b can be inserted into the second groove 41b and can move along the longitudinal direction in the second groove 41b relative to the second groove 41b. Thus, the second portion 38b is able to move relative to the engagement groove <NUM> in the rang e(second range) E2 between the second regulator portion 41e that is the end (front end) of the second groove 41b and the rear end of the lock portion 41c. In other words, the top linkage <NUM> is extendable and retractable to the extent that the second portion 38b moves relative to the second range E2 in the state where the second portion 38b is located in the engagement groove <NUM>. The second range E2 in which the second site 38b moves relative to the engagement groove <NUM> is narrower than the first range E1 in which the first portion 38a moves relative to the engagement groove <NUM>.

As shown in <FIG> and <FIG>, the diameter D3 of the third portion 38c is formed to have the same diameter as the diameter W3 of the lock portion 41c. The third portion 38c can be inserted into the lock portion 41c. Thus, when the third portion 38c is fitted into the lock portion 41c, the top linkage <NUM> is unable to extend and retract. That is, the extension and retraction of the top linkage <NUM> is locked.

As shown in <FIG>, the switching mechanism <NUM> includes an operation lever (operating member) <NUM>, a fixed member <NUM>, a movable member <NUM>, a support member <NUM>, and a biasing spring <NUM>.

The operation lever <NUM> is a member that operates the switching mechanism <NUM> (movable member <NUM>) and extends to the vicinity of the operator seat <NUM>, as shown in <FIG>, and can be operated by an operator seated on the operator seat <NUM>.

As shown in <FIG>, the fixed member <NUM> is fixed to the cylinder 6A, and the base of the operation lever <NUM> is engaged so as to be adjustable in the vertical position. The movable member <NUM> is fixed to the base of the operation lever <NUM>. The support member <NUM> is supported by the movable member <NUM> at one end (front portion) 46a, which can be moved up and down. The support member <NUM> protrudes rearwardly from the movable member <NUM>, and the engagement member <NUM> is fixed to the other end (rear portion) 46b of the support member <NUM>. The biasing spring <NUM> includes a compression spring and is interposed in a compressed manner between one end side 46a of the support member <NUM> and the lower portion 44a of the movable member <NUM>. Thus, the biasing spring <NUM> displaces the support member <NUM> upwardly. The support member <NUM> includes one end side 46a in contact with the upper portion 44b of the movable member <NUM>, thereby regulating its upward movement. The support member <NUM> is capable of moving downward against the force of the biasing spring <NUM> (spring force).

As shown in <FIG>, the movable member <NUM> can be repositioned to a first position P1, a second position P2, and a third position P3. The first position P1 is a position where the first portion 38a can be inserted into the engagement groove <NUM>, as shown in <FIG>. The second position P2 is a position where the second portion 38b can be inserted into the engagement groove <NUM>, as shown in <FIG>. The third position P3 is a position where the third portion 38c can be inserted into the engagement groove <NUM>, as shown in <FIG> and <FIG>.

The movable member <NUM> is operable by an operator seated on the operator seat <NUM> by means of the operation lever <NUM> to change the position between the first position P1, the second position P2 and the third position P3. In detail, the operation lever <NUM> is detachably engaged and disengaged to the fixed member <NUM> with the movable member <NUM> in the first position P1, the second position P2 and the third position P3. In other words, the operation lever <NUM> is engaged with the fixed member <NUM> to hold the movable member <NUM> at the first position P1, the second position P2 or the third position P3. By releasing the engagement of the operation lever <NUM> to the fixed member <NUM>, the movable member <NUM> can be repositioned.

The top linkage controller mechanism <NUM> described in this embodiment is an example and is not limited to the aforementioned configuration. For example, the engagement member <NUM> and the switching mechanism <NUM> may be provided on the rod member 6B and the plate member <NUM> may be provided on the cylinder 6A. The rod member 6B may be pivoted to the top linkage bracket <NUM> and the cylinder 6A may be pivoted to the detachable frame <NUM>.

Next, referring to <FIG>, the coupling configuration (first coupling configuration) of coupling the direct-mounted working machine <NUM> to the tractor <NUM> will be described.

In the first coupling configuration, the movable member <NUM> is first placed at the first position P1, as shown in <FIG>. That is, the first portion 38a is positioned in the engagement groove <NUM> and is capable of relatively moving relative in the first range E1. Before coupling the working machine <NUM>, the top linkage <NUM> is extended and the detachable frame <NUM> is tilted backward, as shown in <FIG>. At this time, as shown in <FIG>, the detachable frame <NUM> is held in a posterior tilt by the first portion 38a touching the first regulator portion 41d, as shown in <FIG>. Meanwhile, the working machine <NUM> is placed on a ground or other ground surface G1 in the working posture, which is a posture for working. The tractor <NUM> is moved backward with the detachable frame <NUM> tilted backward against the working machine <NUM> in this working posture, and the second upper coupler portion <NUM> is positioned below the first upper coupler portion <NUM>, as shown in <FIG>.

Next, the lower linkage <NUM> is pivoted upward to lift the detachable frame <NUM>, and the second upper coupler portion <NUM> is engaged with the first upper coupler portion <NUM>. Then, when the detachable frame <NUM> is lifted further, the front portion of the working machine <NUM> is lifted up and the front portion of the working machine <NUM> moves upward, as shown in <FIG>. As the front portion of the working machine <NUM> moves upward, the working machine <NUM> pivots around the first upper coupling <NUM> in a direction (forward) approaching close to the detachable frame <NUM>, and the first lower coupling <NUM> is automatically engaged with the second lower coupler portion <NUM> in close proximity. At this time, the PIC shaft <NUM> is also automatically coupled to the second universal joint 17B. This causes the working machine <NUM> to be automatically coupled to the tractor <NUM>. When the first lower coupling <NUM> is engaged with the second lower coupler portion <NUM>, the locking mechanism provided in the second lower coupler portion <NUM> is automatically activated, and the locking mechanism regulates the detachment of the first lower coupling <NUM> from the second lower coupler portion <NUM>.

Next, the movable member <NUM> is placed at the third position P3. That is, the movable member <NUM> is placed at a position where the third portion 38c can be inserted into the engagement groove <NUM> (lock portion 41c). However, in the state shown in <FIG>, the first portion 38a is inserted in the first groove 41a and the upper surface 38e of the second portion 38b is in contact with the lower surface of the plate member <NUM> (see <FIG>). In other words, the engagement member <NUM> does not move when the movable member <NUM> is placed at the third position P3. Thus, when the movable member <NUM> is positioned at the third position P3, the movable member <NUM> moves upward relative to the support member <NUM> and the engagement member <NUM>, and the support member <NUM> becomes detached from the upper portion 44b of the movable member <NUM>.

Next, from the state in which the front portion of the working machine <NUM> is moved upward (forward inclining state), as shown in <FIG>, the lower linkage <NUM> is pivoted downward to lower the detachable frame <NUM>. Then, the front portion of the working machine <NUM> is lowered and the front portion of the working machine <NUM> is lowered to take the working posture shown in <FIG>. As the front portion of the working machine <NUM> lowers, the top linkage <NUM> shortens and the plate member <NUM> moves forward with respect to the engagement member <NUM>. In other words, the engagement member <NUM> moves backward relative to the engagement groove <NUM>. When the engagement member <NUM> moves to a position corresponding to the second groove 41b as the top linkage <NUM> shortens, the support member <NUM> and the engagement member <NUM> are lifted by the force the biasing spring <NUM>, so that the second portion 38b fits into the second groove 41b and the upper surface 38d of the third portion 38c touches the lower surface of the plate member <NUM> (see <FIG>).

Then, as shown in <FIG>, when the working machine <NUM> touches the ground plane G1 and takes the working posture, the position of the engagement member <NUM> coincides with the lock portion 41c, and the support member <NUM> moves upward by the force of the biasing spring <NUM>, causing the third portion 38c to insert into the lock portion 41c (see <FIG> and <FIG>). The expansion and retraction of the top linkage <NUM> is locked when the third portion 38c fits into the lock portion 41c.

In this manner, the direct-mounted working machine <NUM> is coupled to the tractor <NUM> in the first coupling configuration by the working machine coupler device <NUM>.

When turning or moving to a neighboring or remote location, the working machine <NUM> can be lifted by the hydraulic system <NUM> and the three-point linkage mechanism <NUM>, and the like, as shown in <FIG>.

As mentioned above, when the working machine <NUM> takes the working posture from the front lifted state, the engagement member <NUM> relatively moves in the engagement groove <NUM> to allow the top linkage <NUM> to shorten. That is, the engagement member <NUM> allows shortening of the top linkage <NUM> when the engagement member <NUM> relatively moves in the engagement groove <NUM> as the working machine <NUM> lowers to take the working posture from the front lifted position.

In detaching the working machine <NUM>, the restriction by the locking mechanism that restricts the first lower coupler portion <NUM> from being detached from the second lower connecting section <NUM> is released, and the switching mechanism <NUM> is placed at the first position P1. The release of the locking mechanism can be operated by the operator seat <NUM> side by, for example, lifting the detachable frame <NUM>.

To bring the switching mechanism <NUM> to the first position P1, the three-point linkage mechanism <NUM> is moved up and down. That is, when a load is applied to the top linkage <NUM>, the third portion 38c does not come out of the lock portion 41c, so the three-point linkage mechanism <NUM> is raised and lowered, and when the load on the top linkage <NUM> becomes zero, the lock on the top linkage <NUM> is released and the third portion 38c can be removed from the lock portion 41c. When the third portion 38c is removed from the lock portion 41c, the top linkage <NUM> is free to expand and contract.

In this state, the working machine <NUM> can be detached from the detachable frame <NUM> by moving the tractor <NUM> forward or by moving the tractor <NUM> forward while gradually lowering after raising the three-point linkage mechanism <NUM>.

Next, referring to <FIG>, the coupling configuration (second coupling configuration) for coupling the towing working machine <NUM> (working machine <NUM> operated in a floating state) to the tractor <NUM> will be described below.

As shown in <FIG>, the towing working machine <NUM> includes a grounding wheel (gauge wheel) <NUM> at the rear portion. The grounding wheel <NUM> is attached to the cover case <NUM> by a bracket member <NUM>. When this towing working machine <NUM> is connected, the working machine <NUM> is also placed on the ground plane G1 in the working posture, which is the working posture.

In the case of coupling the towing type working machine <NUM>, the working machine <NUM> is lifted up and the PIC shaft <NUM> is automatically connected to the second universal coupler portion 17B as well as the first lower coupler portion <NUM> to the second lower coupler portion <NUM> until the PIC shaft <NUM> is automatically connected to the second universal coupler portion 17B, in the same manner as in the case of coupling the direct-mounted working machine <NUM> described above.

That is, with the movable member <NUM> at the first position P1, and with the top linkage <NUM> extended and the detachable frame <NUM> tilted backward, as shown in <FIG>, the tractor <NUM> is moved backward to position the second upper coupler portion <NUM> below the first upper coupler portion <NUM>. Then, from this state, the lower linkage <NUM> is pivoted upward to raise the detachable frame <NUM>, and the second upper coupler portion <NUM> is engaged with the first upper coupler portion <NUM>. Then, when the detachable frame <NUM> is raised further, the working machine <NUM> is lifted and the front portion of the working machine <NUM> moves upward, as shown in <FIG>. As the front portion of the working machine <NUM> moves upward, the working machine <NUM> pivots around the first upper coupler portion <NUM> in a direction approaching close to the detachable frame <NUM> so that the first lower coupler portion <NUM> engages with the second lower coupler portion <NUM> and the PIC shaft <NUM> is automatically coupled to the second universal coupler portion 17B. This causes the working machine <NUM> to be automatically coupled to the tractor <NUM>.

Next, in this second coupling configuration, the movable member <NUM> is placed at the second position P2. That is, the movable member <NUM> is placed at a position where the second portion 38b can be inserted into the engagement groove <NUM>. However, in the state shown in <FIG>, the first portion 38a is inserted into the first groove 41a and the upper surface 38e of the second portion 38b is in contact with the lower surface of the plate member <NUM> (see <FIG>). In other words, the engagement member <NUM> does not move when the movable member <NUM> is placed at the third position P3. Thus, when the movable member <NUM> is positioned at the second position P2, the movable member <NUM> moves upward relative to the support member <NUM> and the engagement member <NUM>, and the support member <NUM> is detached from the upper portion 44b of the movable member <NUM>.

Next, from the forward inclining state in which the front portion of the working machine <NUM> is moved upward, as shown in <FIG>, the lower linkage <NUM> is pivoted downward to lower the detachable frame <NUM>. Then the front portion of the working machine <NUM> is lowered and the working posture of the working machine <NUM> is shown in <FIG>. As the front portion of the working machine <NUM> lowers, the top linkage <NUM> shortens and the plate member <NUM> moves forward with respect to the engagement member <NUM>. In other words, the engagement member <NUM> moves backward relative to the engagement groove <NUM>. When the engagement member <NUM> moves to a position corresponding to the second groove 41b as the top linkage <NUM> shortens, the support member <NUM> and the engagement member <NUM> are raised by the force of the biasing spring <NUM>, so that the second portion 38b fits into the second groove 41b and the upper surface 38d of the third portion 38c touches the lower surface of the plate member <NUM> (see <FIG>).

In this manner, the towing working machine <NUM> is connected to the tractor <NUM> by the working machine coupler device <NUM>.

In the coupling configuration of the towing working machine <NUM>, when the working machine <NUM> takes the working posture shown in <FIG>, the top linkage <NUM> is not locked to extend and retract, but the top linkage <NUM> is regulated to extend and retract within a range (a predetermined range) where the second portion 38b moves in the engagement groove <NUM> relative to the second range E2. In other words, the working machine <NUM> is in the floating state that follows the ground plane G1 in the second range E2, where the second portion 38b moves in the engagement groove <NUM> relative to the ground plane G1. In other words, the expansion and retraction of the top linkage <NUM> is regulated within a predetermined range where the second section 38b moves relative to the floating portion <NUM> (the second groove portion 41b and the lock portion 41c), which allows the working machine <NUM> to follow the ground plane G1. Thus, the engagement groove <NUM> includes the floating portion <NUM> that regulates the expansion and retraction of the top linkage <NUM> to a predetermined range (second range E2) when the working machine <NUM> takes the working posture, allowing the working machine <NUM> to follow the ground plane G1.

In this second coupling configuration of coupling the towing working machine <NUM>, when the working machine <NUM> is turned or moved to a neighboring or remote location, the second portion 38b moves forward relative to the floating portion <NUM> when the working machine <NUM> is lifted by the hydraulic system <NUM>, the three-point linkage mechanism <NUM>, and the like. When the second portion 38b moves to the front end of the floating portion <NUM> and touches the second regulation portion 41e, the extension of the top linkage <NUM> is regulated. This allows the working machine <NUM> to be regulated to lower and lift the working machine <NUM>, as shown in <FIG>.

As described above, when the front portion of the working machine <NUM> is moved downward from the upwardly lifted position to the working posture, either the first coupling configuration or the second coupling configuration can be selected by the switching mechanism <NUM> by selecting the second position P2 or the third position P3.

In the second coupling configuration, in which the towing working machine <NUM> is connected to the traveling vehicle <NUM>, the detachment of the working machine <NUM> is performed in much the same way as the direct-mounted working machine <NUM> described above.

As described in detail above, in the working machine coupler device <NUM> of the present embodiment, when coupling the working machine <NUM> to the tractor <NUM>, the second upper coupler portion <NUM> can be positioned below the first upper coupler portion <NUM> without putting the working machine <NUM> in a forward inclining posture by tilting the detachable frame <NUM> backward. This eliminates the need for a stand to hold the working machine <NUM> in a forward inclining position and allows the working machine <NUM> to be easily connected.

A single top linkage controller mechanism <NUM> can be used to connect both the direct-mounted working machine <NUM> and the towing working machine <NUM>.

In addition, the working machine coupler device <NUM> of this embodiment provides the following effects.

According to the working machine coupler device of claim <NUM>, the working machine <NUM> can be connected to the traveling vehicle <NUM> without having to tilt the working machine <NUM>. Also, the top linkage controller mechanism <NUM> can be easily configured and a direct-mounted work machine <NUM> can be connected.

The engagement groove <NUM> includes the first regulator portion 41d that holds the detachable frame <NUM> in a backwardly inclining state when the engagement member <NUM> contacts the engagement groove <NUM>, and the engagement member <NUM> allows the top linkage <NUM> to be shortened by moving relative to the engagement groove <NUM> when the working machine <NUM> lowers from the front lifting position to the working posture.

According to this configuration, the top linkage controller mechanism <NUM> can be easily configured.

The engagement groove <NUM> includes the floating portion <NUM> that regulates the expansion and retraction of the top linkage <NUM> by fitting the engagement member <NUM> when the working machine <NUM> takes the working posture, within a range that allows the working machine <NUM> to follow the ground plane G1.

According to this configuration, for example, the working machine <NUM> operated in the floating state can be connected.

The floating portion <NUM> includes the second regulator portion 41e that regulates the extension of the top linkage <NUM> by retracting the engagement member <NUM> when the lower linkage <NUM> is pivoted upward to lift the working machine <NUM> from the working posture.

According to this configuration, the working machine <NUM> can be lifted when the working machine <NUM> operated in the floating state is coupled.

The top linkage controller mechanism <NUM> includes the switching mechanism <NUM> that allows selection of one of the first coupling configuration that locks the expansion and retraction of the top linkage <NUM> when the working machine <NUM> takes the working posture, and the second coupling configuration that regulates the expansion and retraction of the top linkage <NUM> to a predetermined range E2 and allows the working machine <NUM> to follow the ground plane G1 when the working machine <NUM> takes the working posture.

According to this configuration, it is convenient to select the coupling configuration of the working machine <NUM>.

The top linkage controller mechanism <NUM> includes the engagement groove <NUM> and the engagement member <NUM> to be engaged with the engagement groove <NUM>, the engagement groove <NUM> includes: the first regulator 41d to hold the detachable frame <NUM> inclining backward with the engagement member <NUM> contacting to the first regulator 41d, the lock portion to be engaged with the engaged member <NUM> to lock stretch of the top linkage <NUM> when the working machine <NUM> takes the working posture in the first coupling configuration, the floating portion <NUM> to be engaged with the engagement member <NUM> to regulate stretch of the top linkage <NUM> within a range allowing the working machine <NUM> to follow a ground surface when the working machine <NUM> takes the working posture in the second coupling configuration, the engagement member <NUM> moves relatively to the engagement groove <NUM> while the working machine <NUM> gradually takes the working posture from a posture where the front portion of the working machine <NUM> is lifted and allows the top linkage <NUM> to be shortened, and the floating portion <NUM> includes the second regulator 41e to contact to the engagement member <NUM> to regulate the stretch of the top linkage <NUM> when the lower linkage <NUM> is moved upward to lift the working machine <NUM> from the working posture.

According to this configuration, the top linkage controller mechanism <NUM>, which can be switched between the first and second coupling configurations, can be easily configured.

Claim 1:
A working machine coupler device comprising:
a top linkage (<NUM>) configured to be pivotally supported on a traveling vehicle (<NUM>), the top linkage (<NUM>) being configured to stretch and shorten;
a lower linkage (<NUM>) configured to be pivotally supported on the traveling vehicle (<NUM>);
a detachable frame (<NUM>) connecting the top linkage (<NUM>) and the lower linkage (<NUM>), the detachable frame (<NUM>) including:
a second upper coupler (<NUM>) configured to be coupled to a first upper coupler (<NUM>) provided to a working machine (<NUM>); and
a second lower coupler (<NUM>) configured to be coupled to a first lower coupler (<NUM>) provided to the working machine (<NUM>); and
a top linkage controller mechanism (<NUM>) to control stretching and shortening of the top linkage (<NUM>), wherein
the second upper coupler (<NUM>) and the second lower coupler (<NUM>) are configured such that the second upper coupler (<NUM>) of the detachable frame (<NUM>) inclining backward is coupled to the first upper coupler (<NUM>) when the lower linkage (<NUM>) is pivoted upward, and the first lower coupler (<NUM>) is configured to move toward and be coupled to the second lower coupler (<NUM>) when a front portion of the working machine (<NUM>) is moved upward, and
the top linkage controller mechanism (<NUM>) is configured to regulate the stretching and shortening of the top linkage (<NUM>) to hold the detachable frame (<NUM>) inclining backward, and allow the top linkage (<NUM>) to be shortened until the working machine (<NUM>) takes a working posture after the lower linkage (<NUM>) is pivoted downward from a state where the front portion of the working machine (<NUM>) is lifted,
characterised in that the top linkage control mechanism includes an engagement groove (<NUM>) and an engagement member (<NUM>) to be engaged with the engagement groove (<NUM>), and the engagement groove (<NUM>) includes a lock portion (41c) to be engaged with the engagement member (<NUM>) to lock the stretching and shortening of the top linkage (<NUM>) when the working machine (<NUM>) takes the working posture.