JPH10191702A - Walking type power tiller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a walking type power tiller in which the strength of link between an engine and a mission case can be improved, the number of parts is reduced and assembly work can be facilitated by attaching a handle and a resistant bar to a bracket integrated with the mission case. SOLUTION: A handle 14 to be extended upward at the back on the rear side of tilling unit and a resistant bar 15 extended downward at the end under the handle 14 are linked to the tilling unit provided with an engine E having a motive force take-out shaft 45 protruded downward, pawl rotor arranged under the engine E and motive force transmission part 12 arranged under the engine E while building a motive force transmission mechanism between the motive force take-out shaft 45 and the pawl rotor inside the mission case, the upper end of mission case is directly bonded to a member 32 integrated with a main body 18 of engine E, and the handle 14 and the resistant bar 15 are attached to a bracket 68 integrated with the mission case.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an engine having a power take-off shaft projecting downward, a pawl rotor disposed below the engine, and a power transmission mechanism between the power take-off shaft and the pawl rotor. A cultivating unit including a power transmission unit built in the case and disposed below the engine, a handle extending upward and rearward behind the cultivating unit, and a resistance rod extending downward and downward below the handle. The present invention relates to a walk-behind tiller to which is connected.

[0002]

2. Description of the Related Art Conventionally, such a walk-type cultivator is well known, for example, from Japanese Patent Application Laid-Open No. 7-26979.

[0003]

However, in the prior art described above, a bracket and a frame are provided between the engine body and the transmission case, and a handle and a resistance bar are attached to the bracket. For this reason, the number of parts becomes relatively large, and the assembling work becomes complicated, a problem occurs in the strength of the joint between the frame and the bracket and the engine and the transmission case, and it is necessary to increase the strength of the joint.

The present invention has been made in view of such circumstances, and has been made possible by connecting the handle and the resistance rod to a tilling unit while minimizing the number of parts and facilitating assembly work. It is an object of the present invention to provide a walking cultivator capable of sufficiently increasing the connection strength between the cultivators.

[0005]

In order to achieve the above object, the present invention provides an engine having a power take-off shaft projecting downward, a pawl rotor disposed below the engine, the power take-off shaft and A power transmission mechanism between the claw rotors is built in a transmission case, and a power transmission unit disposed below the engine; and a handle extending upward and rearward on the rear side of the tillage unit; In a walk-behind cultivator in which a resistance rod extending downward and downward below a handle is connected, an upper end of a transmission case is directly connected to a member integrated with an engine body of the engine, and a bracket integrated with the transmission case is provided with a bracket. A handle and a resistance bar are attached.

According to such a configuration, the upper end of the transmission case integrally including the handle and the bracket to which the resistance bar is attached is directly connected to the member integral with the engine main body, so that the transmission between the engine main body and the transmission case is performed. This eliminates the need for frames and brackets that were required in the past, reducing the number of parts and facilitating assembly work.Also, as the number of parts is reduced, the connection strength between the engine body and the transmission case is sufficient. Can be increased.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on one embodiment of the present invention shown in the accompanying drawings.

FIGS. 1 to 7 show an embodiment of the present invention. FIG. 1 is a side view of a walking type tiller, FIG. 2 is a plan view of a walking type tiller, and FIG. 4 is a lower longitudinal sectional view of the tillage unit, FIG. 5 is an enlarged sectional view taken along line 5-5 of FIG. 4, FIG. 6 is a sectional view taken along line 6-6 of FIG. 5, and FIG. It is a 7-line enlarged sectional view.

Referring first to FIGS. 1 and 2, the walking type cultivator T includes an engine E, a tilling unit 11 disposed below the engine E, and a power transmission for transmitting the power of the engine E to the tilling unit 11. A handle 14 extending upward and rearward at a rear portion of the tillage unit 13 including the portion 12;
4 and a resistance bar 15 extending downward and downward.

In FIG. 3, an engine E is a vertical type four-stroke air-cooled engine, and has an engine body 18 having a cylinder block 16 integrated with a head and a crankcase 17 joined to the cylinder block 16.
The engine body 18 includes a crankcase 17
Are arranged on the rear side of the cylinder block 16 and are arranged in the front-rear direction.

A piston 20 is slidably fitted in a cylinder bore 19 provided in the cylinder block 16, and a crankshaft 22 connected to the piston 20 via a connecting rod 21 has a rotation axis extending vertically. And is rotatably supported by the crankcase 17.

A head cover 23 that forms a valve chamber 24 with the cylinder block 16 is connected to the front end of the cylinder block 16. This valve operating chamber 24 is formed so as to extend from the lower side of the cylinder block 16 to the front end thereof, and reduces the rotational power of the crankshaft 22 to １ ／ to reduce the power of opening and closing the intake and exhaust valves (not shown). A valve train 25 for conversion is housed in the valve train chamber 24.

An oil reservoir 26 is formed in the upper part of the crankcase 17. An oil slinger 27 for stirring the oil stored in the oil reservoir 26 to form an oil mist is provided on the crankshaft 22. Connected to the oil reservoir 2
6 is stored.

At the lower end of the crankshaft 22, a cooling blade 2
9 is fixedly attached to the rotor 30
The ignition coil 31 which constitutes the flywheel magneto 28 in cooperation with 0 is fixed to the lower side of the cylinder block 16.

An engine cover 32 that covers the engine body 18 together with its head and a flywheel magnet 28 is integrally connected to the engine body 18.
A recoil starter 33 connected to the upper end of the engine cover 32 is mounted.
Is provided with an insertion hole 35 for inserting the.

As is clearly shown in FIG.
An exhaust muffler 36 is disposed on the right side of the engine main body 18 along the forward direction of the engine so as to be covered with the engine cover 32.
6a is disposed on the right side of the engine body 18 with the opposite side to the engine body 18, that is, facing outward. Further, an opening 37 for discharging exhaust gas discharged from the exhaust port 36a is provided on the right side of the engine cover 32.

An air cleaner 38 is disposed on the left side of the engine body 18 along the forward direction of the tilling unit 13 so as to be located outside the engine cover 32. It is covered with a cover 39 which is a separate body.

Further, a fuel tank 42 is disposed behind the engine body 18.
2 is fastened to the engine cover 32.

Referring again to FIG. 3, an opening 43 is provided below the engine cover 32 at a position corresponding to a position below the crankshaft 22, and a centrifugal clutch 44 is disposed in the opening 43. The centrifugal clutch 44 includes a power take-off shaft 45 that is coaxial with the crankshaft 22 and protrudes downward from the engine cover 32, and a flywheel magnet 28.
A plurality of clutch shoes 46 supported by the rotor 30 so as to be able to expand in diameter, a clutch drum 47 surrounding the clutch shoes 46 and fixed coaxially to the power take-out shaft 45, and reducing the clutch shoes 46. And a spring (not shown) for urging in the radial direction. When the crankshaft 22, that is, the rotor 30 rotates at a predetermined rotation speed or more, the clutch shoes 46 are pressed against the inner peripheral surface of the clutch drum 47. The rotational power of the crankshaft 22 is transmitted to the power output shaft 45.

Referring to FIG. 4, FIG. 5 and FIG.
The tilling unit 11 includes a tilling shaft 50 extending in the left-right direction on the forward side of the power take-out shaft 45, a pair of left and right inner claw rotors 51, 51 and a pair of left and right outer claw rotors 52, 52 attached to the tilling shaft 50. And disposed below the engine E. Each inner claw rotor 51, 51 has two tilling claws 51a, 51a bent inward on the tip side and two tilling claws 51b, 51 bent outward on the tip side.
b, and each outer claw rotor 52, 52
The four tilling claws 52 bent inward at the tip side
a ... are provided.

The power transmission unit 12 includes a power transmission mechanism 53 for transmitting the power of the power take-off shaft 45 projecting downward from the engine E to the inner and outer pawl rotors 51, 52,. It is built in the case 54. The transmission case 54 includes a shaft housing portion 55a formed in a cylindrical shape extending upward and downward, and a flat box-shaped gear housing portion 55b integrally connected to a lower end of the shaft housing portion 55a and having an open front side. Case body 55 including
And a lid member 56 for detachably closing the front opening end of the gear housing portion 55b. Moreover, the shaft housing 55
The upper end of the centrifugal clutch 44 is directly fastened to the engine cover 32 integrated with the engine body 18 so that a part of the centrifugal clutch 44 is housed in the upper end. The upper end is rotatably supported via a bearing 57. Further, the axially intermediate portion of the tilling shaft 50 in the tilling portion 11 is rotatably penetrated through the gear housing portion 55b, and a pair of seal members 58, 58 and a pair of Bearings 59, 59 are provided.

The power transmission mechanism 53 has a power take-out shaft 4 at the upper end.
5, a transmission shaft 61 rotatably housed in a shaft housing 55a, a cylindrical worm 62 provided below the transmission shaft 61, and a gear housing closed by a lid member 56. The worm wheel 63 is rotatably accommodated in the tilling unit 50 and is rotatably housed in the tilling shaft 50 of the tilling unit 11. You.

The upper end of the transmission shaft 61 and the shaft housing 55a
A seal member 64 is provided between the upper ends of the transmission shaft 61 and the shaft housing 55a above and below the cylindrical worm 62.
Bearings 65 and 66 are provided between them. Further, the shaft housing 55
The lower end of “a” is closed by a cap 57.

Referring also to FIG. 7, a bracket 68 extending rearward along the forward direction of the tilling unit 13 is integrally provided at an upper end portion of the transmission case 54, that is, an upper end portion of the shaft storage portion 55a. The handle 14 and the resistance bar 15 are attached to the bracket 68.

The handle 14 is provided with a pair of left and right pipes 69, 69 extending rearward so as to increase the distance therebetween toward the rear side, and holding portions 71, 71 at the rear end. And a handle main portion 70 formed in a substantially U-shape so that both front ends of the handle main portion 14b can be inserted and removed from the rear side inside the rear ends of both pipes 69, 69. Fitting recesses 69a, 69 to be fitted
a is provided respectively. Thus, the fitting recesses 69a, 69
a on both sides of the front end of the handle main portion 14b fitted to the handle main portion 14a and the rear ends of both pipes 69, 69.
Screw members 72, 72 are respectively inserted from the b side, and nuts 73, 7 that engage with the outer ends of the rear ends of both pipes 69, 69.
The handle 3 is screwed into each of the screw members 72, 72, so that the handle main portion 70 is connected to both pipes 69, 69 to form the handle 14.

At the rear of the bracket 68, a pair of pipe supports 7 having a semicircular cross section open to both the left and right sides.
8 and 78 are integrally provided so as to be inclined rearward and upward, and approximately half the circumference of the front end of both pipes 69 and 69 in the handle 14 is fitted to both pipe support portions 78 and 78. Pressing members 79, 79 are in contact with the outer circumferences of the two pipes 69, 69 on the opposite side to the two pipe support portions 78, 78, and one of them is provided at two places spaced apart in the axial direction of the pipes 69, 69. A nut 81 engaging with the other pressing member 79 is screwed into a bolt 80 penetrating from the pressing member 79 to the other pressing member 79.
4 is attached to the bracket 68.

The bracket 68 is integrally provided with a cylindrical resistance rod support portion 83 having an insertion hole 82 inclined backward and downward between the two pipe support portions 78, 78. In a state where the upper end portion of the resistance rod 15 is inserted, a nut 85 that engages with the bolt 84 that penetrates the resistance rod support part 83 and the resistance rod 15 from one side of the resistance rod support part 83 to the other side of the resistance rod support part 83 Is screwed, so that the resistance bar 15 is fixedly attached to the resistance bar support portion 83. Further, the resistance bar 15 is provided with a plurality of through-holes 86 through which the bolts 84 are passed, at a plurality of locations spaced apart in the longitudinal direction of the resistance bar 15.
By selectively selecting one of the...
The distance from 8 to the lower end of the resistance bar 15 can be changed.

In this manner, the handle 14 and the resistance bar 15 are attached to the bracket 68 which is integral with the transmission case 54. As shown in FIG.
4 is an extension line L of the handle 14 toward the front side.
₁ is set to pass near the rotation axis of the claw rotors 51, 52, that is, the axis of the tilling shaft 50. Further, when the tilling unit 13 is viewed from the side, the handle 14 and the resistance bar 15 are connected to the rear portion of the tilling unit 13 at a position lower than the engine E so as to intersect in a substantially “X” shape. However, the center of gravity position G of the walk-behind cultivator T is set in a range defined above and below by an extension L ₁ toward the front side of the handle 14 and an extension L ₂ toward the front side of the resistance rod 15. Thus, the inclination angles of the handle 14 and the resistance bar 15 are set. In order to maintain the tilling performance at a high level, it is desirable that the center of gravity G is located between the rotation axis of the tilling unit 11, that is, the position directly above the tilling shaft 50 and the extension lines L ₁ and L ₂ .

A guard plate 87 that covers the upper and rear sides of the tilling unit 11 is fixed to the bracket 68. The guard plate 87 is for preventing mud from splashing toward the worker during the tilling operation by the tilling unit 11, and is provided integrally with the guard plate 87, for example, at two locations in pairs. The parts 87a are bolts 88 and nuts 89.
Is fixed to the bracket 68.

Next, the operation of this embodiment will be described. The exhaust muffler 36 has its exhaust port 36a directed to the opposite side of the engine body 18 so that the right side of the engine body 18 along the forward direction of the tilling unit 13 can be used. The exhaust gas from the exhaust muffler 36 is discharged toward the right outside of the engine body 18. Therefore, during the tilling work by the walking cultivator, it is possible to avoid the exhaust gas from being applied to the worker behind the engine E by gripping the handle 14 as much as possible, and the tilling work can be performed more smoothly.

Since the air cleaner 38 is disposed on the opposite side of the exhaust muffler 36, that is, on the left side of the engine body 18 along the forward direction of the tilling unit 13, it is possible to prevent the air cleaner 38 from sucking exhaust gas as much as possible. In addition, it is possible to extend the life of the filter member of the air cleaner 38 by sucking the fresh air into the air cleaner 38, and further, by arranging the exhaust muffler 36 and the air cleaner 38 on both the left and right sides of the engine body 18, the tilling is performed. This can contribute to equalization of the left and right weight balances in the machine T.

The upper end of the transmission case 54 in the power transmission section 12 is directly connected to the engine cover 32 integral with the engine body 18, and another member is interposed between the engine body 18 and the transmission case 54. Is unnecessary, and the mission case 5
Since the handle 14 and the resistance bar 15 are attached to the bracket 68 provided integrally with the upper end of the bracket 4, the number of parts can be reduced and the assembling work can be facilitated, and the number of parts is reduced. Engine body 18
In addition, the connection strength between the transmission cases 54 can be sufficiently increased.

Furthermore forward claw rotor 51 ... than the power takeoff shaft 45, 52 ... in addition to the rotation axis is located, the extension line L ₁ claw rotor 51 to the front side of the handle 14 ..., 52
The inclination angle of the handle 14 is determined so as to pass in the vicinity of the rotation axis of..., And the center of gravity of the entire cultivator T is moved upward and downward by extension lines L ₁ and L ₂ of the handle 14 and the resistance rod 15 to the front side. It is set within the specified range. For this reason,
The mounting portion of the handle 14 and the resistance rod 15 to the tillage unit 13 can be set at a position relatively close to the center of gravity G, and the handle 14 and the resistance rod 15 during the tillage work can be set.
Vibration can be suppressed as much as possible.

Moreover, the handle 14 and the resistance bar 15
Since the tilling unit 13 is connected to the bracket 68 of the tilling unit 13 in a substantially “X” shape when viewed from the side, the strength of the mounting portion of the handle 14 and the resistance rod 15 to the bracket 68 is reduced. Can be relatively high.

Although the embodiments of the present invention have been described in detail, the present invention is not limited to the above embodiments, and various design changes can be made without departing from the present invention described in the appended claims. It is possible to do.

[0036]

As described above, according to the present invention, the number of parts is reduced by eliminating the need for a frame or a bracket between the engine body and the transmission case, which is conventionally required. And the connection strength between the engine body and the transmission case can be sufficiently increased by the reduced number of parts.

[Brief description of the drawings]

FIG. 1 is a side view of a walking tiller.

FIG. 2 is a plan view of a walking type cultivator.

FIG. 3 is an upper longitudinal sectional view of a tilling unit.

FIG. 4 is a lower longitudinal sectional view of the tilling unit.

FIG. 5 is an enlarged sectional view taken along line 5-5 of FIG.

FIG. 6 is a sectional view taken along line 6-6 in FIG. 5;

FIG. 7 is an enlarged sectional view taken along line 7-7 of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 12 ... Power transmission part 13 ... Tilling unit 14 ... Handle 15 ... Resistance bar 18 ... Engine main body 32 ... Engine cover as a member integral with the engine 45 ... Power take-out Shafts 51, 52: Claw rotor 53: Power transmission mechanism 54: Transmission case 68: Bracket E: Engine T: Walking cultivator

Claims (1)

[Claims] An engine (E) having a power take-off shaft (45) projecting downward, a pawl rotor (51, 52) disposed below the engine (E), and the power take-off shaft (4).
5) and a power transmission mechanism (53) between the pawl rotors (51, 52) built in a transmission case (54) and a power transmission section (12) disposed below the engine (E). A walk in which a handle (14) extending rearward and upward and a resistance rod (15) extending rearward and downward below the handle (14) are connected to the tilling unit (13) including the tilling unit (13). In the tiller, the upper end of the transmission case (54) is directly connected to a member (32) integral with the engine body (18) of the engine (E), and a bracket (68) integral with the transmission case (54). ), The handle (14) and the resistance rod (15) are attached thereto.