JP3408914B2 - Lawn mower traveling operation structure - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traveling operation structure of a lawnmower equipped with a cruise control device (travel speed holding device), and more particularly to simplification of a cruise release mechanism associated with brake operation.

[0002]

2. Description of the Related Art In recent years, lawn mowers have a total of three brake pedals, which are a left and right brake pedals for individually controlling the left and right brake devices and a main brake pedal for simultaneously operating the left and right brake devices. As a small turn such as mowing around a grove, it is possible to conveniently perform single-brake turning traveling in which only the driving wheels inside the turning are braked and turning, and simultaneous braking of both left and right driving wheels during traveling. is there. For example, Japanese Patent Application No. 6-27466 filed earlier
No. 8 makes the above proposal.

[0003]

[Problems to be Solved by the Invention] In addition, actual Kaihei 4-294
It is known from Japanese Patent Publication No. 34-34, etc. that a traveling speed holding device, a so-called cruise control device, is provided so that the user can travel at a constant speed without continuously depressing the traveling pedal and can concentrate on lawn mowing operation or steering operation.
Therefore, an object of the present invention is to propose a structure in which a brake system having three brake pedals and a cruise control device are reasonably equipped without waste.

[0004]

[Means for Solving the Problems]

[Structure] A first invention for achieving the above object is to interlock a left brake and a left brake pedal for a left drive wheel through a left relay arm pivotally supported by an intermediate shaft, and to a right drive wheel. A right brake and a right brake pedal for the vehicle are interlockingly connected via a right relay arm pivotally supported by the intermediate shaft, and the left brake pedal and the right brake pedal are arranged in proximity to each other, and the left and right relay arms are arranged. A main brake pedal capable of rotating the intermediate shaft so as to simultaneously operate the vehicle and a speed holding device capable of holding the traveling speed at a set speed are provided, and the speed holding action is released when the main brake pedal is depressed. As described above, the release lever for releasing the holding action of the speed maintaining device and the operation arm attached to the intermediate shaft are interlockedly connected, and the pin provided on the intermediate shaft is connected to the left and right relay arms.
The left and right relay arms are fitted to the respective long holes in the circumferential direction to allow relative rotation of the left and right relay arms with respect to the intermediate shaft in the depression direction of the left and right brake pedals.
Individual depression of the right brake pedal, and simultaneous depression
It is characterized in that the speed retaining action is not released by only the manual operation .

According to a second aspect of the invention, in the first aspect of the invention, the releasing operation for the speed maintaining device accompanying the depression of the main brake pedal is completed before the depression amount of the main brake pedal at which the braking operation is started is reached. It is set.

[Operation] In order to make the left and right independent brake systems and the main brake system for simultaneous left and right braking function without mutual interference, Japanese Patent Application No. Hei 6-27466 of the above-mentioned proposed technique is required.
As shown in No. 8 (see FIG. 2 in particular), the interlocking linkage part having a double shaft structure is required, and the cruise control device is required to have a function of releasing the cruise action in cooperation with the brake operation. is there.

Therefore, according to the first aspect of the invention, the structure for linking the cruise control device and the brake system is provided with the release lever for the speed holding action (cruise action) as the main brake pedal is stepped on, and the above-mentioned double mechanism. It can be realized by interlockingly connecting with an operation arm attached to an intermediate shaft for forming a shaft structure. In other words, the intermediate shaft for the braking system is also configured as the shaft for the cruise release mechanism.

Incidentally, it is a common general technical knowledge to release the cruise action in accordance with the brake operation, but if the operation timings of the two are inappropriate, that is, the braking force generated by the brake operation and the low speed by the cruise function are caused. If the driving state overlaps with the driving state, there is a disadvantage that the braking distance is extended or the driving system is overloaded. Therefore, according to the configuration of claim 2, since the cruise release accompanying the brake operation is set to be completed before the braking force actually occurs, that is, in the play area of the pedal depression, the driving force is always applied. Braking can be performed in a non-acting state, and good braking can be achieved such as stopping at an appropriate braking distance according to a set value.

[Effect] As a result, in the lawnmower according to the first or second aspect of the present invention, a brake system having three brake pedals and a cruise control are provided while cost reduction and installation space saving are achieved by sharing components. It was possible to provide a rational traveling operation structure that is organically connected to the device.

In the lawnmower according to the second aspect, there is an advantage that the above effect can be obtained while obtaining an appropriate braking state by the cooperation of the mechanism for releasing the cruise in the "play" area of the brake operation.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show a front mount type lawn mower, 1 is a mower, 2 is a body frame, 3
Is a driving front wheel, 4 is a steering rear wheel, 5 is a control section, 6 is an engine, 7 is a mission case, 8 is a driving seat, 9 is a step floor, 10 is a speed change pedal, 11 is a main brake pedal, and 12 is a vehicle for running. It is an HST (hydrostatic type continuously variable transmission).

The power from the engine 6 is input through the HST 12 to the transmission case 7, where the left and right front wheels 3, 3 are provided.
Left and right brake pedals 1 arranged in parallel on the left side of the control tower 14 on the step floor 9 while the independent brake devices 13 and 13 are installed respectively (see FIGS. 6 and 9).
The left and right brake devices 13 can be operated separately by operating 5 and 16. As a result, brake turning can be performed by braking only the front wheel 3 on the inside of the turn.
Further, between the right brake pedal 16 and the control tower 14, a diff lock pedal 19 interlocked with a diff lock device 17 installed in the mission case 7 by a rod 18 is arranged.

On the other hand, as shown in FIG. 3, on the right side of the control tower 14, a main brake pedal 11 for simultaneously operating the left and right brake devices 13, 13 and a speed change pedal 10 for operating the HST 12 are provided. . As shown in FIG.
The operated arm 12b attached to the 12 trunnion shaft 12a and the speed change pedal 10 are interlockingly connected by the rod 20, and the cam plate 23 integrally attached to the trunnion shaft 12a and the spring 21 pull and urge the spring. A known neutral return mechanism A is configured by the return arm 22. Then, if the speed change pedal 10 of the balance arm structure is depressed to the front side, it moves forward, if it depresses to the rear side, it moves backward, and if the depression is released, the neutral return mechanism A automatically returns to the neutral state.

Next, the operation structure of the brake will be described. As shown in FIG. 3 to FIG. 9, the intermediate shaft 24 facing left and right in front of the mission case 7 and on the back side of the step floor.
Is installed, and the left relay arm 25 located at the left end of the shaft 24 and the right relay arm 26 having a right cylinder shaft portion 26a that is long in the left and right are externally fitted and supported, and the left relay arm 25 includes the left front rod 27 and the left front rod 27. The left brake pedal 15 and the left brake device 13 are interlockingly connected by the rear rod 28. The right relay arm 26 connects the right brake pedal 16 and the right brake device 13 by interlocking with the right front rod 29 and the right rear rod 30. As described above, the left and right brake devices 13 can be operated separately.

The above-mentioned intermediate shaft 24 is pivotally supported with respect to the machine body. The operation arm 31 attached to the shaft 24 and the main brake pedal 11 are interlockingly connected by a rod 32, and the intermediate shaft 24 is planted in the intermediate shaft 24. Upright pins 24a, 24a
To the left cylinder shaft portion 25a and the right cylinder shaft portion 2 of the left relay arm 25.
It is fitted into circumferential elongated holes 25b and 26b formed in 6a. In a free state in which the pedals 15, 16 and 11 are not depressed, the pins 24a and 24a are attached to the elongated holes 25b and
26b, the left and right brake devices 13, 13 can be simultaneously braked by depressing the main brake pedal 11, and the left and right brake devices 13, 13 by the left and right brake pedals 15, 16 are set. It is possible to brake each separately.
The operation arm 31 is the rod 3 on the main brake pedal side.
It has a two-arm structure for two and for a rod 48 on the cruise control device B side described later.

Next, the elevating structure of the mower 1 will be described. As shown in FIGS. 1, 2 and 6, the left and right lifting links 33, 34 are driven between the front part of the mission case 7 and the mower housing 1H, and are driven by the hydraulic cylinder 35 installed in the upper part of the mission case 7. Lift arm 3
6 are provided respectively, and a connecting link 47 for interlockingly connecting the elevating links 33, 34 and the lift arm 36 is provided to constitute an elevating link mechanism C. That is, when lawn mowing work is performed, the lift arm 36 is swung downward to lower the mower 1 to a lowering work position where the grounding wheel 1b is in contact with the ground, and when the vehicle is moving, the lift arm 36 is swung upward to move the mower 1. Is lifted to the ascending and retracted position where it has been levitated above the ground.

Then, as shown in FIGS. 6 and 7, when the mower 1 is raised to the ascending and retracting position, the left elevating link (link member of the link member is provided just below the rod portions 15a, 16a of the left and right brake pedals 15, 16. One example) 33 is arranged so that it is positioned relative to each other, and in this non-working state, a one-brake restraint mechanism D is configured to restrain restraint so that the left and right brake levers 15 and 16 cannot be depressed. That is, the left lifting link 33 itself corresponds to "a restraining member K that can be switched between a restraining position that disables depression of the left and right brake pedals 15 and 16 and a release position that allows depression. By the way, as shown in FIGS. 7 and 8, the left and right brake pedals 15 and 16 have a coaxial structure in which they are fitted and supported by a fulcrum shaft 19j for the differential lock pedal 19, so that the cost can be reduced by sharing the parts. .

Further, the brake device 13 is set to be in a so-called half-brake state even when the left and right brake levers 15 and 16 are fully depressed so that the braking lock does not occur during one-side braking. That is, as shown in FIGS. 7 and 8, the rod portion 1 of the left and right brake pedals 15 and 16 is
Stopper pins 15p and 16p are provided so as to project from 5a and 16a, and the stopper pins 15p and 16p come into contact with the upper surface of the step floor 9 as the pedal is stepped on, thereby restricting stepping. In this case, the left and right brake pedals 15 and 1 of the stopper pins 15p and 16p
It is convenient to adjust the position with respect to 6 or the height of the stopper pin contact surface of the step floor 9 so that the maximum stepping margin and the half braking force can be adjusted.

The left and right front rods 27, 29 described above engage with the elongated holes formed in the arm portions of the left and right relay arms 25, 26, and in the free state, they are in front of the left and right front ends of the elongated holes. It is set so that the rods 27 and 29 are located (see FIG. 4). That is, the left and right front rods 27, 29
Since the main brake pedal 11 moves along with the depression of the main brake pedal 11, the structure for preventing the left and right brake pedals 15 and 16 from being brake-locked by the long hole connection structure is used, but the brake lock by the depression of the main brake pedal 11 is prevented. It is possible. The front left and right rods 27 and 29 are equipped with turnbuckles 27a and 29a, respectively.
By the adjustment, the braking force can be adjusted when the left and right brake pedals 15 and 16 are fully depressed.

As shown in FIG. 9, a cruise control device B that acts on the HST 12 to keep the traveling speed at a set value is provided above the mission case. This device B includes a cruise lever 37, a biasing mechanism 38 capable of holding the lever 37 at an arbitrary operation position, an interlocking rod 39 capable of interlocking the cruise lever 37 and the operated arm 12b, and a biasing mechanism 38. And a release arm 40 capable of canceling the action.

As shown in FIG. 10, the biasing mechanism 38 includes a pressing cam 41, a receiving cam 42, and both cams 41,
It includes a support shaft 43 to which 42 is fitted, a winding spring 44 that presses the pressing cam 41, and the release arm 40 described above. The pair of friction rings 45, 45 mounted between the cams 41, 42 can press and hold the plate lever portion 37a, which is the base of the cruise lever 37, and straddle the contact portions of the both 41, 42. Thus, the riding cam mechanism 46 is configured.

That is, the winding spring 44 is normally the pressing cam 4
By pushing 1 in the axial direction, the cruise lever 37 is pressed and held by the cams 41 and 42 at the operation position at that time, and the release arm 40 is swung to move the ride-on cam mechanism 46 to run up, and Both cams 41, 42 move relatively away from each other against the biasing force of the spring 44, and the pressure contact holding action is released. The release arm 40 is interlocked with the operation arm 31 of the intermediate shaft 24 by the rod 48, and the pressing contact holding action of the cruise lever 37 is released as the main brake pedal 11 is depressed.

Further, the interlocking rod 39 on the HST 12 side is engaged with the tip of the rod portion 37b of the cruise lever 37 via the long hole 39b of the plate member 39a fixed to the front end thereof, and the HST 12 is in the neutral state. Yes, and the cruise lever 37 is in the non-acting position (OFF
(Position), the rod portion 37b has the long hole 39
It is set to be located in the middle of the front and rear of b. In other words, the setting speed maintaining action of the cruise lever 37 acts only when moving forward, and does not interfere with the cruise lever 37 when moving the backward movement of the speed change pedal 10 in which the interlocking rod 39 moves backward.

However, when the cruise lever 37 is swung forward from the OFF position in order to perform lawn mowing work or traveling traveling at a constant speed, only the cruise lever 37 moves to the cruise start position ON due to the play of the long hole 39b. If the cruise lever 37 is swung forward, the long hole 39
After the play of b is completed, the interlocking rod 39 is moved, and HST1
When the cruise lever 37 is released, the cruise control device B operates and the cruise lever 37 is held at the operating position.
When the main brake pedal 11 is depressed in the cruise running state, the release arm 40 is operated to release the pressure contact holding action, the HST 12 returns to the neutral position, and the cruise lever 3 is returned by the return spring (not shown).
7 also returns to the OFF position.

Incidentally, the cruise release accompanying the simultaneous operation of the brake devices 13 and 13 is set so as to be performed by so-called "play allowance" until the brake is actually actuated as the main brake pedal 11 is depressed. ing. That is, as shown in FIG. 9, the main brake pedal 1
During the play depression angle α of 1, the riding cam mechanism 4
6 is activated and the HST 12 is returned to neutral.

[Other Embodiment] In the present embodiment, the intermediate shaft 24 is provided independently according to various conditions such as the frame layout of the machine body. However, the above-mentioned proposed technique (Japanese Patent Application No. 6-2746).
No. 68), the present invention can be applied to those having a linkage structure in which three pedal shafts themselves have a double shaft structure.

It should be noted that reference numerals are added to the claims for convenience of comparison with the drawings, but the present invention is not limited to the configurations of the accompanying drawings by the entry.

[Brief description of drawings]

[Figure 1] Left side view of front mount lawn mower

[Figure 2] Right side view of front mount lawn mower

FIG. 3 is a plan view of a control unit showing an arrangement structure of various pedals.

FIG. 4 is a mechanism diagram showing the structure of a brake operation system.

FIG. 5 is a sectional view showing an interlocking portion between the intermediate shaft and the left and right relay arms.

FIG. 6 is a side view showing the relationship between the left and right brake pedals and the lifting link.

FIG. 7 is a plan view showing the relationship between the left and right brake pedals and the lifting link.

FIG. 8 is a front view showing the relationship between the left and right brake pedals and the diff lock pedal.

FIG. 9 is a right side view showing the shift operation structure and the operation structure of the main brake pedal.

FIG. 10 is a cross-sectional view of essential parts showing the structure of the cruise control device.

[Explanation of symbols]

11 Main brake pedal 13 Brake device 15 Left brake pedal 16 Right brake pedal 24 Intermediate shaft 25 Left relay arm 26 Right relay arm 31 Operation arm 40 Release lever B Speed holding device

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kenichi Nakajo, 64 Ishizukita-machi, Sakai City, Osaka Prefecture Kubota Co., Ltd.Sakai Factory (72) Yoshihiro Kawahara, 64, Ishizukita-machi, Sakai City, Osaka Prefecture Kubota Sakai Co., Ltd. In-house (56) Reference JP-A-6-40264 (JP, A) JP-A-1-90553 (JP, A) JP-A-2-124332 (JP, A) JP-A-1-156160 (JP, A) ) JP-A-4-19276 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B60T 7/00 B60T 7/04

Claims (2)

(57) [Claims] 1. A left brake (13) for a left driving wheel and a left brake pedal (15) are interlockingly connected via a left relay arm (25) pivotally supported by an intermediate shaft (24), and Right brake (13) and right brake pedal (1) for the right drive wheel
6) and the right relay arm (26) pivotally supported by the intermediate shaft (24), and the left brake pedal (15) and the right brake pedal (16) are arranged close to each other. , The left and right relay arms (2
5), (26) to simultaneously operate the intermediate shaft (24)
Is provided with a main brake pedal (11) capable of rotating and a speed holding device (B) capable of holding the traveling speed at a set speed, and a speed holding action is provided as the main brake pedal (11) is depressed. In order to be released, the release lever (40) for releasing the holding action of the speed holding device (B) and the operation arm (31) attached to the intermediate shaft (24) are interlockingly connected, and the intermediate shaft ( 24) provided with pins (24a), (24
a) the left and right relay arms (25) and (26) respectively
Fitted in the long holes (25b) and (26b) in the circumferential direction
In the depression direction of the left and right brake pedals (15) and (16), relative rotation of the left and right relay arms (25) and (26) with respect to the intermediate shaft (24) is allowed.
The left and right brake pedals (15) and (16)
The speed holding operation is possible for individual stepping operation and simultaneous stepping operation.
A lawn mower traveling operation structure configured so that it will not be released . 2. The release operation for the speed maintaining device (B) accompanying the depression of the main brake pedal (11) is performed until the depression amount of the main brake pedal (11) at which the braking operation is started. The traveling operation structure of the lawn mower according to claim 1, which is set to be completed.