JPH1128010A - Mower lifting and lowering operation structure of lawn mower - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce labor required in mower-attaching operation by preventing raising of a lifting and lowering link mechanism by action of an assist mechanism after separating mower, though operating force required in mower raising operation can be reduced by action of the assist mechanism. SOLUTION: This mower lifting and lowering operation structure is equipped with an assist mechanism liftably and detachably connecting a mower through a lifting and lowering link mechanism to a traveling mechanism and applying an operating lever for mower lifting and lowering action and force in a mower- raising direction in raising operation by an operation lever to the lifting and lowering link mechanism. In this case, a lowering control tool 24 for controlling lowering due to own weight of mower by contact with an engaging pin 23A provided in the lifting and lowering link mechanism is provided and an engaging part 24Z for engaging and holding the engaging pin 23A at lowering position for attaching and detaching the mower is formed in the lowering control tool 24.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mower which is connected to a traveling body via a lifting link mechanism so as to be movable up and down and detachably. The present invention relates to a mower elevating operation structure of a lawn mower including an assist mechanism for applying a force in a mower elevating direction at the time of an ascent operation by a mower.

[0002]

2. Description of the Related Art In a mower lifting / lowering operation structure for a lawn mower as described above, an assist mechanism applies a force in a rising direction to a mower via a lifting / lowering link mechanism to raise the mower by operating an operation lever. The operation force required for is reduced. In the mower elevating operation structure of the lawn mower configured as described above, conventionally, as disclosed in, for example, Japanese Patent Application Laid-Open No. 8-156419, a state in which a plurality of contact portions have a step along the circumferential direction. The mowing during the mowing operation with the mower suspended by regulating the lowering of the mower's own weight by the contact between the selected contact portion and the engaging pin provided on the lifting link mechanism by the formed rotary cam type. There has been provided a descent control adjuster for adjusting and setting the height.

[0003]

However, in the above-mentioned prior art, in order to perform maintenance of the mower, the mower is lowered to a lower position for attaching and detaching the mower by operating an operation lever and then removed from the lifting link mechanism. When the mower is attached to the lifting link mechanism again, the lifting link mechanism will be lifted from the lower position for attaching and detaching the mower. It is necessary to lower the mechanism to the lower position for attaching and detaching the mower by operating the operation lever, and to attach the mower to the lifting link mechanism while maintaining the lowered state. In other words, according to the above-described prior art, at the time of the mower mounting operation, a considerable operation force for lowering the lifting link mechanism against the action of the assist mechanism is required, and the mounting operation is performed while maintaining the lowered state. It took a lot of work.

An object of the present invention is to reduce the operating force required for the mower lifting operation by the action of the assist mechanism, while preventing the lifting link mechanism from rising due to the action of the assist mechanism after the mower has been disengaged and mounting the mower. An object of the present invention is to reduce the labor required for work.

[0005]

In order to achieve the above object, according to the first aspect of the present invention, a mower is vertically and freely detachably connected to a traveling body via an elevating link mechanism. The mower elevating operation mechanism of the lawn mower, comprising an operating lever for mower elevating operation, and an assist mechanism for applying a mower elevating direction force at the time of the elevating operation by the operating lever, wherein the mower elevating operation mechanism comprises: A descent regulating adjuster that regulates the descent of the mower by its own weight by contact with the provided engagement pin is provided,
An engaging portion for engaging and holding the engaging pin at a lower position for attaching and detaching the mower is formed on the lowering regulating adjuster.

According to the first aspect of the present invention, when it is necessary to remove the mower from the elevating link mechanism during maintenance of the mower or the like, the mower can be detached from the mower by operating the operation lever. After the mower is removed by lowering to the lowering position and engaging the engaging portion of the lowering regulating adjuster with the engaging pin of the lifting link mechanism and holding the engaging pin at the lowering position for attaching and detaching the mower. The lifting link mechanism can be prevented from rising due to the action of the assist mechanism. Thus, when the mower is attached to the lifting link mechanism again, it is not necessary to lower the lifting link mechanism to the lower position for attaching and detaching the mower by lever operation against the action of the assist mechanism, while maintaining the lowered state. There is no need to attach a mower to the lifting link mechanism. That is, at the time of the mower mounting operation, it is possible to eliminate the operation force and labor for lowering the lifting link mechanism against the action of the assist mechanism, and the labor for maintaining the lowered state.

[Effect] Accordingly, while the operation force required for the mower raising operation can be reduced by the action of the assist mechanism, when the mower is removed, the lifting link mechanism can be used for attaching and detaching the mower regardless of the operation of the assist mechanism. Since it can be held at the lowered position, the labor and labor required for the mower mounting operation can be reduced.

According to the second aspect of the present invention,
In the first aspect of the present invention, the lowering position for attaching and detaching the mower is set further lower than the lower limit position of the cutting height adjustment range.

According to the second aspect of the present invention, at the time of the mower attaching / detaching operation, the mower is lowered to the descending position for moor attaching / detaching, whereby the mower can be brought into a stable state in which the mower is grounded on the ground. by this,
As compared with the case where the mower is in the suspended state, the pulling force at the connecting portion between the mower and the elevating link mechanism can be weakened, so that the mower can be easily attached to and detached from the elevating link mechanism.

[Effect] Therefore, the mower can be easily attached to and detached from the lifting link mechanism.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the entire side surface of a lawn mower. This lawn mower is provided with a mid-mount by connecting a mower 3 to a middle position in the front-rear direction of a traveling body 1 via a lifting link mechanism 2 so as to be able to move up and down. The mold is configured. The traveling body 1 includes an engine 5 mounted on a front portion of the body frame 4,
A radiator 6 arranged behind the engine 5; an axle frame 7 supported at the front of the body frame 4; a hydrostatic continuously variable transmission 8 and axle case 9 supported at the rear of the body frame 4; A front wheel 10 as a steering wheel mounted on each of the left and right ends of the vehicle, a rear wheel 11 as a drive wheel mounted on each of the left and right ends of the axle case 9, a steering handle 12 linked to the front wheel 10, and a body frame 4. It is configured as a riding type by a driver's seat 13 and the like arranged at the rear upper part.

As shown in FIGS. 1-4, the lifting link mechanism 2
Are a pair of left and right front links 14 spanning the front part of the body frame 4 and the front part of the mower 3, and a pair of left and right bridges spanning the front and rear middle part of the body frame 4 and the rear part of the mower 3. A rear link 15, a rotating shaft 16 rotatably supported around a left-right axis P <b> 1 at a rear portion of the body frame 4, a pair of left and right swing arms 17 fixed to both ends of the rotating shaft 16,
And a pair of right and left linking links 18 laid across the rear link 15 and the swing arm 17, and the like, so as to form a parallel quadruple type. The lifting link mechanism 2 includes an operation lever 19 for a mower elevating operation supported by the body frame 4 so as to be swingable around a left-right axis P2, and a force in the mower elevating direction at the time of the mower elevating operation by the operation lever 19. Is provided.

The operating lever 19 has a first operating arm 1
9A and the right swing arm 17 are linked via an operation rod 21, and the mower 3 is lifted up via the lifting link mechanism 2 by an upward swing operation around the left-right axis P2. The mower 3 is moved through the elevating link mechanism 2 by the downward swinging operation around the left-right axis P2.
Is to be lowered. At the base end of the operation lever 19, a locking pin 19 </ b> B that is urged toward the distal end of the operation lever 19 by a coil spring (not shown) provided inside the operation lever 19 protrudes. An operating tool 19C is provided at the distal end of the operating lever 19 to move the locking pin 19B to the base end side against the bias of the coil spring when pressed. A restricting guide plate 22 having a long hole 22A for restricting the swing range of the operating lever 19 between the operating pin 19 and the locking pin 19B is provided upright from the body frame 4 at the base end side of the operating lever 19. ing. At the upper end of the long hole 22A, the locking pin 19B is urged by the coil spring when the operation lever 19 is swung to the upper limit position.
22B, and a recess 22C at the lower end of the elongated hole 22A, into which the locking pin 19B is engaged by the bias of the coil spring when the operation lever 19 is swung to the lower limit position. These recesses 22B,
The operation lever 19 can be fixedly held at the upper limit position or the lower limit position by the engagement of the locking pin 19B to 22C. Further, the locking operation of the operating lever 19 at the upper limit position or the lower limit position can be released by releasing the locking pin 19B from the concave portions 22B, 22C by pressing the operating tool 19C.

The assist mechanism 20 includes a first gas cylinder 20A spanning the body frame 4 and an operation arm 23 fixed to the rotating shaft 16, a body frame 4 and a second operation arm 19D of the operation lever 19, and Is constituted by the second gas cylinder 20B erected over the
When operating the operation lever 19, the first gas cylinder 20A
The second gas cylinder 20B and the second gas cylinder 20B apply an upward force to the mower 3 via the lifting link mechanism 2, so that the operating force required to raise the mower 3 by operating the operation lever 19 can be reduced. ing.

The right swing arm 17 is formed with an arc-shaped long hole 17A having the left-right axis P1 as a fulcrum. The right swing arm 17 and the operation lever 19 are formed in the long hole 17A. One end of the operation rod 21 for linking the two is engaged. Rotating shaft 1 in lifting link mechanism 2
6 are provided at the left and right intermediate portions with engaging pins 2 protruding leftward.
A support arm 23 having 3A is fixed. The mower 3 is attached to the body frame 4 by contact with the engagement pin 23A.
Cam type descent control adjuster 24 which controls the descent of its own weight
Is rotatably mounted around the axis P3 in the front-rear direction via the support shaft 25. As shown in FIGS. 4 and 6, first to seventh contact portions 24 </ b> A to 24 </ b> G are arranged on the rear surface of the lowering regulation adjuster 24 in the clockwise direction in rear view in that order along the circumferential direction. Is formed in a state of being connected to. Each of the first to seventh contact portions 24A to 24G is formed so as to have a step in which the contact position with the engagement pin 23A is displaced toward the front of the aircraft in that order. As the mating pin 23A comes into contact with the first contact portion 24A, the lowering position of the mower 3 by its own weight becomes higher. As shown in FIGS. 1, 2 and 4, at the front end of the support shaft 25,
A knob 26 for rotating the lowering regulating adjuster 24 is mounted. According to the above configuration, by operating the knob 26, the lowering regulating adjuster 24 is rotated about the longitudinal axis P3 to contact the engaging pin 23A from the first to seventh contact portions 24A to 24G. By changing the setting of the object to be hit, the lowering position of the mower 3 in the mowing operation state in which the operating lever 19 is fixedly held at the lower limit position, that is, the mowing height by the mower 3 can be adjusted.
The long hole 17A of the swing arm 17 allows the cutting height adjustment (change of the setting of the lowering control position of the mower 3) by the lowering control adjuster 24 while the operation lever 19 is fixedly held at the lower limit position. Is set to

Incidentally, since the assist mechanism 20 has the second gas cylinder 20B spanned over the body frame 4 and the second operation arm 19D of the operation lever 19,
In the mowing operation state in which the operation lever 19 is fixedly held at the lower limit position, only the first gas cylinder 20A applies an upward force to the mower 3 via the lifting link mechanism 2. As a result, the mower 3 can be reduced by the thrust generated by the contact between the mower 3 and another object during the mowing operation, while reducing the operating force required to raise the mower 3 by operating the operation lever 19. Unnecessary rise can be suppressed.

As shown in FIGS. 5 and 6, the lowering regulating adjuster 24 has an engaging portion 24Z for engaging and holding the engaging pin 23A at a lowering position for attaching and detaching the mower to the seventh contact portion 24G. The first contact portion 24A is recessed and formed in a continuous state.
With this configuration, when it becomes necessary to remove the mower 3 from the elevating link mechanism 2 when performing maintenance or the like of the mower 3, the lowering regulating adjuster 24 is moved to the rear with the operation lever 19 fixed and held at the lower limit position. The mower 3 can be lowered by its own weight toward the lower position for attaching and detaching the mower, and the lowering position for attaching and detaching the mower 3 by rotating the mower 3 by its own weight in the counterclockwise direction as viewed. With the movement of the lifting link mechanism 2, the engagement pin 23A of the lifting link mechanism 2 can be engaged with the engaging portion 24Z which is the lower position for attaching and detaching the mower in the lowering regulation adjusting tool 24. The engagement pin 23A can be engaged and held at the lower position for attaching and detaching the mower irrespective of the action of the assist mechanism 20 after the mower 3 is removed from the motor. Able to prevent the rise of the lift link mechanism 2 by the action of strike mechanism 20 so as to lift the link mechanism 2 can be kept in the lowered position for the mower detachable regardless attachment and detachment of the mower 3. In other words, after the mower 3 is removed, which has occurred when the engaging portion 24Z for engaging and holding the engaging pin 23A of the lifting link mechanism 2 at the lower position for attaching and detaching the mower has not been formed on the lowering regulating adjuster 24. Of the lift mechanism from the lower position for attaching and detaching the mower can be eliminated by the action of the assist mechanism 20. As a result, when the mower 3 is attached to the lift link mechanism 2 again, the assist mechanism 20 can be removed. There is no need to lower the lifting link mechanism 2 to the lower position for attaching and detaching the mower by operating the operation lever 19 against the action of
Since it is not necessary to attach the mower 3 to the lifting link mechanism 2 while maintaining the lowered state, the labor and labor required for the mower mounting operation can be reduced.

The position of the engagement portion 24Z of the lowering regulation adjuster 24 with the engagement pin 23A of the lifting link mechanism 2 is greater than the engagement position of the engagement pin 23A with the seventh contact portion 24G. Also, it is formed so as to have a step with the seventh contact portion 24G so as to be located on the front side of the fuselage. In other words, the lower position for attaching / detaching the mower in a state where the engagement pin 23A of the lifting link mechanism 2 is engaged with the engagement portion 24Z of the lowering control adjuster 24 restricts the engagement pin 23A of the lifting link mechanism 2 to lower. The cutting height is set to be lower than the lower limit position of the cutting height adjustment range that is in contact with the seventh contact portion 24G of the adjusting tool 24. From this configuration, by lowering the mower 3 to the lower position for attaching and detaching the mower during the mower attaching / detaching work, the state of the mower 3 can be brought into a stable state in which the mower 3 is in contact with the ground, and when the mower 3 is in the suspended state. In comparison, since the pulling force at the connecting portion between the lifting link mechanism 2 and the mower 3 can be reduced, the work of attaching and detaching the mower 3 to and from the lifting link mechanism 2 can be facilitated.

As shown in FIGS. 7 and 8, a transmission arm 27 having a substantially V-shaped cam surface 27A is fixed to a trunnion shaft 8a of the hydrostatic continuously variable transmission 8. By performing a swing operation of the transmission arm 27 via an operation system linked to the arm 27, switching between forward and backward movement and shifting can be performed. An eccentric pin 28 is mounted below the trunnion shaft 8a in the hydrostatic continuously variable transmission 8 so that the mounting angle with respect to the hydrostatic continuously variable transmission 8 can be changed. Eccentric pin 2
8, a neutral arm 30 is mounted to return the transmission arm 27 to the neutral position by pressing the roller 30A against the cam surface 27A of the transmission arm 27 by the bias of the coil spring 29. Neutral arm 30
The fine adjustment of the engagement position between the roller 30A and the cam surface 27A for returning the transmission arm 27 to neutral by changing the mounting angle of the eccentric pin 28 with respect to the hydrostatic continuously variable transmission 8 Can be done. or,
On the side of the eccentric pin 28 in the hydrostatic continuously variable transmission 8, a neutral arm 30 is provided with respect to the eccentric pin 28,
A check protrusion 31 is provided to prevent the neutral arm 30 from being mounted in the wrong orientation, so that the neutral arm 30 can be easily attached to the eccentric pin 28 without wrong orientation. Has become.

[Other Embodiments] Other embodiments of the present invention will be listed below. The lawnmower may be a front mower type or a reel mower type. The engagement position between the engagement portion 24Z of the lowering regulation adjuster 24 and the engagement pin 23A of the lifting link mechanism 2 is set to the seventh contact portion 24.
The step between the engaging portion 24Z and the seventh contacting portion 24G is eliminated so that the contacting position of the engaging pin 23A with the engaging pin 23A is the same in the longitudinal direction of the fuselage. May be set so that the lowering position for the cutting and the lower limit position of the cutting height adjustment range are at the same height position. The assist mechanism 20 may be constituted by a single gas cylinder or a coil spring, or may be constituted by a plurality of coil springs or a combination of a gas cylinder and a coil spring. Various changes can be made to the structure of the descent control adjuster 24.

[Brief description of the drawings]

FIG. 1 is an overall side view of a lawn mower.

FIG. 2 is a longitudinal sectional side view of a main part of a lawn mower showing a relationship between a lifting link mechanism and a lowering regulating adjuster.

FIG. 3 is a side view showing the operation of the assist mechanism.

FIG. 4 is a vertical sectional rear view of a main part of the lawn mower showing a relationship between a lifting link mechanism and a lowering regulating adjuster.

FIG. 5 is a perspective view of a lowering regulating adjuster showing a shape of an engaging portion.

FIG. 6 is an exploded view of the lowering regulating adjuster showing the shape of the engaging portion.

FIG. 7 is a side view of a main part showing a neutral return structure of the hydrostatic continuously variable transmission.

FIG. 8 is a cross-sectional plan view of a main part showing a neutral return structure of the hydrostatic continuously variable transmission.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Traveling body 2 Elevating link mechanism 3 Mower 19 Operation lever 20 Assist mechanism 23A Engagement pin 24 Lowering regulation adjuster 24Z Engagement part

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Mikio Yuki 64 Ishizukita-cho, Sakai City, Osaka Prefecture Inside Kubota Sakai Plant (72) Inventor Yoshio Tomiyama 64 Ishizukita-cho, Sakai City, Osaka Prefecture Kubota Sakai Manufacturing Co., Ltd. Inside

Claims (2)

[Claims] 1. A mower is vertically and detachably connected to a traveling body via an elevating link mechanism. An operating lever for mower elevating operation is connected to the elevating link mechanism. A mower elevating and lowering operation structure of a lawn mower provided with an assist mechanism for applying a force in a direction, comprising: a descent regulating adjuster that regulates a descent of the mower by its own weight by contact with an engagement pin provided in the elevating link mechanism. A mower elevating and lowering operation structure for a lawn mower, wherein said lowering regulating adjuster is provided with an engaging portion for engaging and holding said engaging pin at a lowering position for attaching and detaching a mower. 2. The mower lifting and lowering operation structure for a lawn mower according to claim 1, wherein the lower position for attaching and detaching the mower is set lower than a lower limit position of a cutting height adjustment range.