JP2534805Y2 - Mission case support structure for riding lawn mower - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a transmission case supporting structure for a riding lawn mower.

(B) Conventional technology Conventionally, as an example of a riding lawn mower, Japanese Patent Publication No. Sho 62-19
There is one described in Japanese Patent Publication No. 803.

That is, such a riding lawn mower has a lawn mowing part mounted directly below a body frame of a traveling part, and the traveling part has a prime mover mounted at a front part of the body frame, a transmission case provided at a rear part, and a transmission case. Left and right front wheels are attached to both left and right ends of a front axle case disposed below a front part, and left and right rear wheels are attached to left and right sides of a transmission case via a rear axle case.

(C) Problems to be solved by the invention However, in the case of the riding lawn mower, the inside ends of the rear axle bracket case are attached to the left and right side walls of the transmission case, respectively, and the rear wheels are attached to the outside end of each rear axle case. Therefore, there is a problem that the impact force applied to the rear wheels during traveling is transmitted to the transmission case via the rear axle case.

For this purpose, the transmission case is formed firmly by increasing the thickness of the side wall of the transmission case, etc.
Although a failure caused by an impact force or the like is prevented from occurring in a transmission mechanism or the like built in the transmission case, there is a problem that the weight of the transmission case increases and the weight of the entire body increases.

(D) Means for Solving the Problems Therefore, in the present invention, the lawn mowing part is mounted directly below the body frame of the traveling part, the transmission case is mounted on the rear part of the body frame, and the left and right rear wheels are mounted on the transmission case. In a riding lawn mower connected and connected, the upper ends of the left and right rear axle brackets are respectively attached to the outer surfaces of a pair of left and right left and right frames forming an airframe,
A riding lawn mower characterized in that right and left rear wheels are attached to a lower portion of each rear axle bracket, and left and right end portions of a transmission case formed wider than an interval between left and right frames by each rear axle bracket. A mission case support structure is provided.

(E) Function / Effect According to the present invention, the following function / effect is produced.

That is, when the lawn mowing operation is performed, the traveling part is driven while the lawn mowing part is driven, so that the lawn mowing part can mow turf and the like bred on the ground.

At this time, the rear axle bracket is attached to each of the left and right ends of the transmission case formed wider than the space between the left and right frames, and the transmission case is mounted on the left and right frames. The applied impact force is transmitted to the left and right frames via the respective rear axle brackets, and is not directly transmitted to the transmission case, thereby preventing the transmission case from being damaged.

Moreover, since the upper ends of the left and right rear axle brackets are attached to the outer surfaces of the left and right frames, respectively, the impact force applied to the left and right rear wheels can be reliably received by the outer surfaces of the left and right frames.

Therefore, even if it is not necessary to take measures such as increasing the thickness of the side wall of the transmission case in order to strengthen the transmission case, it is possible to prevent the transmission mechanism built in the transmission case from being damaged by an impact force or the like. Therefore, the thickness of the side wall of the transmission case can be made as small as possible, so that the weight of the transmission case and the weight of the body can be reduced.

Furthermore, since the left and right rear wheels are attached to the lower portion of each rear axle bracket, the distance between the left and right rear wheels and the transmission case can be reduced, and another member for supporting the left and right rear wheels can be eliminated. Can,
The body can be reduced in size and weight.

(F) Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

(A) shown in FIGS. 1 and 2 is a riding lawn mower having a transmission case support structure according to the present invention.

In such a riding lawn mower (A), a lawn mowing part (2) is attached to a lower part of the traveling part (1) via a lifting mechanism (3) so as to be able to move up and down directly below the traveling part (1). The grass collection section (5) is attached through the bracket (3), and the grass collection section (5) and the lawn mowing section (2) are connected to each other by a grass grass transport pipe (6).

The traveling section (1) includes a prime mover section such as an engine (11) at a front section of the body frame (10), an operation section (12) at a center section, and a hydraulic type switchable at a rear section. A step transmission (HST) (13) and a transmission case (14) are provided. Left and right front wheels (15) and (15) are attached to the front left and right lower sides of the body frame (10).
The right and left rear wheels (16) and (16) are attached to the left and right sides of 4), and the output from the engine (11) is transmitted to the hydraulic stepless transmission (13) and the lawn mower (2) via the drive mechanism (22). )
The mowing part (2) can be driven while running, and the steering wheel (18) and the front and rear wheels (15) (15) (16) (16)
Are interlocked and connected via a steering mechanism (23) to enable steering and steering.

In FIGS. 1 and 2, (17) is a hood, (18) is a steering wheel, (19) is a seat, (20) is a fender,
(21) is a step.

Also, as shown in FIG. 3, the body frame (10)
Left and right frames (30) and (30) arranged opposite each other at a fixed interval in the left and right width direction, front wheel support frames (31) installed between the front parts of both frames (30) and (30), and both frames (30) The steering gear seat (32) installed between approximately the center of the (30) and the rear of both frames (30) (30), and the output from the engine (11) is hydraulically continuously variable. Equipment (1
3) The counter shaft support frame (33) for transmitting to the lawn mowing part (2), and the operation lever of the continuously variable transmission (13) installed between the rear ends of both frames (30) (30). (13c)
And a lever support frame (34) for supporting the lever.

In FIG. 3, reference numeral (35) denotes a support shaft suspended between the front ends of the left and right frames (30) and (30) to support the lifting mechanism (3), and (36) denotes a lifting mechanism (3). Raising and lowering mechanism support brackets protruding from the approximate center of the left and right frames (30) and (30) toward the left and right sides to support, respectively (37)
Is a step support bracket protruding from the approximate center of the left and right frames (30) and (30) to the left and right sides, respectively. (38) is a lifting cylinder support bracket, (39)
Is an extraction shaft support bracket for supporting the power extraction shaft (48) of the lawn mowing part (2).

As shown in FIGS. 4 and 5, the drive mechanism (22) includes a first drive mechanism (22a) and a second drive mechanism member (22).
b) and the third drive mechanism (22c).

The first drive mechanism (22a) includes the engine (11)
An output shaft (40) protruding upward, a counter shaft (41) vertically supported on the left side of the counter shaft support frame (33), and a shaft vertically on the right side of the steering gear seat (32). The first drive belt (43) is connected to the output pulley (40a), the first counter pulley (41a), and the idler pulley (4) between the supported idler shaft (42) and the idler pulley (4).
2a).

The second drive mechanism (22b) is provided with a counter shaft (4
The second drive belt (45) is connected to the second counter pulley (41b) and the HST pulley (44a) between the input shaft (44) projecting upward from the hydraulic continuously variable transmission (13) and the hydraulic continuously variable transmission (13). ).

The third drive mechanism (22c) is provided with a counter shaft (4
A third drive belt (47) is connected to a third counter pulley (41c) between the power take-out shaft (46) attached to the take-out shaft support bracket (39) and transmitting power to the lawn mowing part (2). ) And a power take-off pulley (46a).

In FIG. 4, (48) is a first tension clutch mechanism, (48a) is a first tension arm, (48b) is a first tension roller, (48c) is a first tension spring, and (48d) is a roller support. Axis. (49) is the second
(49a) is a second tension arm, (49b) is a second tension roller, (49c)
Is the second tension spring, (49d) is the arm spindle,
(49e) is a roller support shaft. (50) is a third tension clutch mechanism, (50a) is a third tension arm, (50b) is a third tension roller, (50c) is a third tension spring, (50d) is an arm support shaft, (50e) Is a roller support shaft.

Further, as shown in FIG. 5, the power take-off shaft (46) is provided with an input shaft (80) provided in the lawn mowing case (2a) of the lawn mowing portion (2).
And a drive shaft (81) that can be extended and contracted in the vertical axis direction.
The input shaft (80) is linked to a lawn mower drive mechanism (82) provided on the ceiling surface of the lawn mower case (2a), and the lawn mower is driven by the drive mechanism (82). The blade (2b) of the section (2) can be rotated (grass mowing drive).
(83) and (84) are universal joints.

As shown in FIG. 6, the steering mechanism (23) includes a pitman arm (51) interlockingly connected to a steering handle (18).
In addition, the front wheel steering mechanism (52) and the rear wheel steering mechanism (53) are interlocked and connected via front and rear drag rods (54) and (55), respectively, and the left and right front and rear wheels (15) (15) ( 16)
(16) Four-wheel steering is possible. (56) is a pitman gear, (56a) is a gear connecting pin, and (57) is a pinion gear.

In addition, the front wheel steering mechanism (52) includes left and right front wheels (15).
The knuckle arms for left and right front wheels (60) and (61) attached to (15) are linked and connected via front tie rods (62), and the knuckle arm for left front wheels (80) is a pitman arm (51). And are linked via a front drag rod (54). (85) is the front axle bracket, (86) and (87) are the left and right kingpins, (62a) (6
2b) is a tie rod connecting pin, (54a) and (54b) are drag rod connecting pins, and (15a) is a front axle.

In addition, the rear wheel steering mechanism (53) includes left and right rear wheels (16).
The left and right rear wheel knuckle arms (63) and (64) attached to (16) are linked and connected via rear tie rods (65). The right rear wheel knuckle arm (64) and the pitman arm (51) ) And the rear drag rod (55). (65a) and (65b) are tie rod connecting pins, (55a) and (55b) are drag rod connecting pins,
(16a) is a rear axle.

In the above configuration, the gist of the present invention lies in the support structure of the transmission case (14), which will be described below with reference to FIGS. 7 and 8.

That is, the transmission case (14) is installed below the rear portions of the left and right frames (30) and (30) via the left and right rear axle brackets (71) and (71). The upper and lower cases (14a, 14b) are formed to extend slightly in the direction and slightly wider than the interval between the left and right frames (30), (30), and a speed change mechanism (not shown) is provided inside. More each rear wheel drive shaft (70)
(70) protruding left and right and laterally outward, and each drive shaft (70)
0) is inserted into the shaft insertion holes (72) (72) provided at the lower part of the left and right rear axle brackets (71) (71), and each end is connected to the rear axle (16a) (16a) by the universal joint (7).
3) Linked through (73). (79) is a case connecting bolt.

Moreover, the upper and lower cases (14) of the transmission case (14)
a) The middle part of the rear surface of (14b) is extended rearward, and the upper and lower cases (13a) (13)
b) is integrally formed.

Also, left and right rear axle brackets (71) (71)
Attach the upper end mounting parts (71a) (71a) to the outer surfaces of the left and right frames (30) (30) with bolts (74), respectively.
The transmission case stays (71b) (71b) are formed by extending the middle part of each bracket (71) (71) from just below the left and right frames (30) (30) to the side inward, forming the stays (71b) Attach the left and right portions of the transmission case (14) between the lower surfaces of the (71b) with the mounting bolts (75) and (75), and extend the brackets (71) and (71) halfway down the rear wheel. A pair of upper and lower connecting pieces (71d) (71d), which form connecting portions (71c) and (71c) and protrude from upper and lower portions of the connecting portions (71c) and (71c), respectively, have a substantially C-shaped rear wheel in a front view. The upper and lower ends of the connecting brackets (76) and (76) are pivoted and connected by vertical vertical pivot pins (79) and (79), respectively, and each rear axle ( 16a) and (16a) are supported by bearings (77) and (77).

Also, the knuckle arm for a rear wheel described above (63) (64)
Are connected to lower ends of the rear wheel connecting brackets (76) and (76) by connecting bolts (78) and (78).

The embodiment of the present invention is configured as described above, and according to the embodiment, the following operation and effect are produced.

That is, when the lawn mowing operation is performed by the riding lawn mower (A), the traveling unit (1) is driven while driving the lawn mowing unit (2).
, It is possible to mow turf and the like bred on the ground in the lawn mowing section.

At this time, at the left and right ends of the transmission case (14) formed wider than the space between the left and right frames (30) (30),
The rear axle brackets (71) and (71) are attached, respectively, and the transmission case (14) is mounted on the left and right frames (30) (30).
6) The impact force applied to (16) is transmitted to the left and right frames (30) and (30) via the rear axle brackets (71) and (71), and is not directly transmitted to the transmission case (14). 14) It is possible to prevent damage beforehand.

In addition, since the upper ends of the left and right rear axle brackets (71) and (71) are attached to the outer surfaces of the left and right frames (30) and (30), the impact force applied to the left and right rear wheels (16) and (16) is reduced. The outer surfaces of the left and right frames (30) and (30) can be reliably received.

Therefore, the transmission mechanism built in the transmission case (14) can be subjected to impact force without taking measures such as increasing the thickness of the side wall of the transmission case (14) in order to strengthen the transmission case (14). In order to prevent the occurrence of a failure or the like, the thickness of the side wall of the transmission case (14) is made as small as possible to reduce the weight of the transmission case (14) and the weight of the aircraft. Can be achieved.

Furthermore, since the left and right rear wheels (16) and (16) are attached to the lower part of each rear axle bracket (71) and (71), the distance between the left and right rear wheels (16) and (16) and the transmission case (14) is increased. Can be reduced, and separate members for supporting the left and right rear wheels (16) (16) can be omitted, and the body can be reduced in size and weight.

Also, the rear wheel knuckle arms (63) and (64) are attached to the rear wheel connection brackets (76) and (76) so that four-wheel steering can be performed.
By simply replacing the rear wheel connection brackets (76) (76) and the left and right rear axle brackets (71) (71) with two-wheel steering brackets, the transmission case (14) and the body frame (10) can be used as is, Four-wheel steering and two-wheel steering can be shared.

The rear wheel drive shafts (70) and (70) can be extended outward to the left and right, respectively, and the rear wheels (16) and (16) can be attached to the tip of each drive shaft (70) (70) to enable two-wheel steering. It can also be.

[Brief description of the drawings]

FIG. 1 is a side view of a riding lawn mower having a transmission case support structure according to the present invention. FIG. 2 is a plan view of the riding lawn mower. FIG. 3 is a plan view of an airframe of the riding lawn mower. FIG. 4 is a plan view of a driving mechanism of the riding lawn mower. FIG. 5 is a side view of a driving mechanism of the riding lawn mower. FIG. 6 is an explanatory plan view of a steering mechanism of the riding type mower. FIG. 7 is a partially cutaway rear view of the support structure of the transmission case. FIG. 8 is a partially cutaway plan view of the transmission case structure. (A): Riding lawn mower (1): Running part (2): Lawn mowing part (10): Body frame (14): Transmission case (15): Front wheels (16): Rear wheels (30): Left and right sides Frame (71): Rear axle bracket

Continued on the front page (56) References JP-A-58-149824 (JP, A) JP-A-63-24640 (JP, U) JP-A-63-154631 (JP, U) JP-A-61-227026 (JP , U) Japanese Utility Model Showa 57-46149 (JP, U) JP-B 62-19803 (JP, B2)

Claims (1)

(57) [Scope of request for utility model registration] A lawn mowing part (2) is mounted directly below a body frame (10) of a traveling part (1).
0) A transmission lawn mower with a transmission case (14) attached to the rear, and left and right rear wheels (16) (16) interlocked and connected to the transmission case (14). The upper ends of the left and right rear axle brackets (71) and (71) are attached to the outer surfaces of the pair of left and right frames (30) and (30), respectively, and the left and right rear wheels ( 16) Attach (16) and use the rear axle brackets (71) (71) to attach the left and right frames (30).
A transmission case support structure for a riding lawn mower, wherein left and right ends of a transmission case (14) formed wider than the interval of (30) are provided.