JPH0823701A - Shift structure of walk-behind management machine - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] To make it possible to carry out multi-speed shifting of the running system and forward / reverse speed shifting and multi-speed shifting of the PTO system while making the gear shifting mechanism compact. [Structure] A plurality of shift gears G _5, G supported on a third shaft 10 are operated by shifting a plurality of shift gears G _1, G ₂ of a PTO gear shift mechanism 20 spline-fitted to the first shaft 8.
₆ is configured so that it can be selectively engaged, and another plurality of shift gears G _3, G ₄ of the PTO system transmission mechanism 20 spline-fitted to the second shaft 17 are shift-operated to perform a plurality of transmission gears G _5, G ₆ Is configured so that it can be selectively occluded, and these two sets of shift gears G _1, G ₂ , G _{3, and} G ₄ are always occluded regardless of the shift state, and the first shaft 8 and the second shaft 17 are opposite to each other. Driven to rotate in two directions, and two sets of shift gears G _1, G ₂ , G _3,
One of G ₄ is selectively engaged with transmission gears G _5, G ₆ .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speed change structure of a walk-behind management machine for performing various intermediate management work in a field.

[0002]

2. Description of the Related Art Conventionally, in a walk-behind management machine, a PTO system gear shifting mechanism and a traveling system gear shifting mechanism have been incorporated as independent mechanisms in a mission case.

[0003]

Therefore, if the number of gears of the traveling system is set to be large and the PTO system can perform forward / reverse gear shift and multiple gear shifts so as to cope with various works, the gears and There was a problem that the number of parts of the shaft increased and the entire gear transmission mechanism became large. The present invention
By making rational improvements to the gear shift mechanism, it is possible to make the gear shift mechanism compact and to perform the multi-speed shift of the traveling system and the forward / reverse shift and the multiple-speed shift in the PTO system. To aim.

[0004]

In order to achieve the above object, the present invention has the following constitution. In other words, the invention according to claim 1 is a P shaft fitted and mounted on the first shaft.
A plurality of shift gears of the TO-type gear speed change mechanism are shift-operated so that the plurality of speed change gears supported by the third shaft can be selectively engaged, and the second shaft is spline-fitted.
A plurality of shift gears of the TO transmission mechanism are shift-operated to selectively engage the plurality of shift gears, and
These two sets of shift gears are always engaged regardless of the shift state, and the first shaft and the second shaft are rotationally driven in opposite directions, and one of the two sets of shift gears is selectively used as the shift gear. By engaging the gears, the PTO shaft interlockingly connected to the speed change gear can be configured to be driven in the forward direction and the reverse direction, respectively, and the forward rotation power and the reverse rotation power from the first shaft and the second shaft can be shifted in the traveling system gears. It is characterized in that it is configured so as to input to each mechanism and perform a multi-speed shift including a reverse speed.

The invention according to claim 2 is the invention according to claim 1, wherein the first shaft is an input shaft for receiving engine power, the second shaft is an intermediate transmission shaft, and the third shaft is the third transmission shaft. The shaft is a traveling system output shaft.

[0006]

According to the structure of claim 1, the two sets of shift gears in the PTO gear shift mechanism are constantly engaged with each other so that the second shaft always rotates in the direction opposite to the first shaft. Since the normal rotation power and the reverse rotation power are input to the traveling system gear transmission mechanism, the two sets of shift gears function as transmission gears that transmit different powers in the rotation direction to the traveling system gear transmission mechanism.

According to the second aspect of the invention, the traveling system output shaft functions as a support shaft of the transmission gear in the PTO system gear transmission mechanism.

[0008]

Therefore, according to the present invention, the following effects can be expected. That is, according to the invention of claim 1, P
Since two sets of shift gears in the TO-type gear speed change mechanism are used as transmission gears for transmitting different motive power in the rotation direction to the traveling type gear speed change mechanism, the number of gears as a whole is reduced by using the gears in common. As a result, the gear shift mechanism can be made compact, and the multi-speed shift of the traveling system and the forward / reverse shift and the multi-speed shift can be performed by the PTO system.

Further, according to the invention of claim 2, the number of shafts as a whole can be reduced by using the shafts in common, which is more effective for downsizing the gear transmission mechanism.

[0010]

1 and 2 show an overall side surface of a walk-behind management machine according to the present invention in a one-wheel traveling mode, and FIG. 3 shows an overall side surface in a two-wheel traveling mode. This walk-type management machine includes an engine 1, a mission case 2, wheels 3, a rotary tilling device 4, a steering handle 5, and the like. The engine 1 is made of sheet metal and extends forward from the mission case 2. An output shaft 7 that is mounted on and connected to a frame 6 and is provided on the left lateral side of the engine 1 and an input shaft 8 of the transmission case 2 are interlockingly connected by a belt transmission mechanism 9. On the right side of the mission case 2 is the output shaft 1 of the running system.
In the one-wheel drive mode, the output of the traveling system output shaft 10 is transmitted to the first axle case 11 arranged on the right lateral side of the mission case 2 in the one-wheel drive mode. The single wheel 3 pivotally supported on the lower left lateral side of the first axle case 11 is driven, and in the two-wheel traveling mode, as shown in FIG.
As shown in, the output of the traveling system output shaft 10 is transmitted to the second axle case 13 via the intermediate transmission case 12 disposed on the right lateral side of the mission case 2, and the lower end sides of the second axle case 13 are transferred to both sides. A pair of left and right wheels 3, 3 pivotally supported on the side are driven. Also, mission case 2
A power take-out case portion 2a is extended to the rear part, a PTO shaft 14 is projectedly provided on the right lateral side thereof, and the rotary case 4a of the rotary tiller 4 is connected to the power take-out case portion 2a. , Power transmission from the PTO shaft 14 to the pawl shaft 4b is performed.

The basic configuration of the walk-behind management machine according to the present invention is as described above, and the configuration of each part will be described in detail below.

The belt transmission mechanism 9 is provided with a tension type main clutch 15, and a grip lever type main clutch lever 16 for operating the tension type main clutch 15 is provided in the steering handle 5.
The main clutch 15 is provided on the left hand grip 5a, and the main clutch 15 is disengaged by gripping the main clutch lever 16, and the main clutch 15 is engaged when released.

As shown in FIG. 5, in the transmission case 2, the input shaft 8 as a first shaft, the intermediate speed change shaft 17 as a second shaft, the traveling system output shaft 10 as a third shaft, and the PTO.
The intermediate shaft 18 and the PTO shaft 14 of the system are provided, the PTO system gear shift mechanism 20 is incorporated in the left half of the case, and the traveling system gear shift is provided in the right half of the case. The mechanism 21 is incorporated.

The PTO gear speed change mechanism 20 is an integral shift gear G splined onto the input shaft 8 so as to be shiftable.
₁ , G ₂ , integral shift gears G ₃ and G ₄ externally fitted to the intermediate transmission shaft 17 so as to be shiftable, and a traveling system output shaft 1
A pair of transmission gears G ₅ and G ₆ loosely fitted in 0,
The wide shift gears G ₂ and G ₄ are constantly engaged. Further, the gear G ₇ which bite into the gear G ₆ is provided in the intermediate shaft 18, a gear G ₈ which is loosely fitted in the gear G ₇ and PTO shaft 14 is occlusion, further, the gear G ₈ and PTO P that meshes with shaft 14
The TO clutch 22 is interlockingly connected.

Therefore, the power take-off shaft 14 can be driven at the first forward speed by shifting the shift gear G ₁ to the left and engaging it with the transmission gear G ₅ , and the shift gear G ₂ can be shifted to the right. it is possible to drive the PTO shaft 14 in the forward second speed by causing occlusion to the speed change gear G _6. Further, the PTO shaft 14 can be driven in the first reverse speed by shifting the shift gear G ₃ to the left and engaging the transmission gear G ₅ .
By shifting the shift gear G ₄ to the right and engaging it with the transmission gear G ₆ , the PTO shaft 14 can be driven in the second reverse rotation speed.

The operation shafts 23 and 24 of the shift forks 23a and 24a of the same specifications engaged with the shift gears G ₁ and G ₂ and the shift gears G ₃ and G ₄ are mounted on the upper part of the mission case 2, The right ends of the operation shafts 23 and 24 protruding outward are selected by the PTO gear shift lever 25 and are pushed and pulled.
The operation shafts 23 and 24 are restrained by the double meshing prevention mechanism 26 interposed between the operation shafts 23 and 24 to prevent simultaneous shift operation, and the operation shafts 23 and 24 are provided with ball detent mechanisms 23b and 24b, respectively. Moreover, the assembling holes of the ball detent mechanisms 23b and 24b are machined in directions perpendicular to each other.

Further, as shown in FIG. 11, the clutch member 22a of the PTO clutch 22 is shift-operated by the cam action of the inclined cam groove 28a and the engagement pin 28b accompanying the rotation of the operating shaft 27. And a blip-type PTO clutch lever 29 provided on the right hand grip 5b of the steering handle 5 is operated to disengage the clutch.

The traveling system gear shifting mechanism 21 includes a gear G ₉ integrated with the input shaft 8 and a gear G ₁₀ loosely fitted in the input shaft 8.
Integral shift gears G ₁₁ and G ₁₂ slidably fitted to the boss portion of the gear G ₁₀ , a gear G ₁₃ integrated to the intermediate transmission shaft 17, and a pair of splines externally fitted to the intermediate transmission shaft 17. Transmission gears G ₁₄ , G ₁₅ , a pair of gears G ₁₆ , G ₁₇ loosely fitted to the intermediate transmission shaft 17, a gear G ₁₈ integrated with the traveling system output shaft 10, and a traveling system output shaft 10 loosely fitted. It comprises a gear G ₁₉ , and a shift gear G ₂₀ splined onto the boss of the gear G _{19 so} as to be shiftable, and includes a gear G ₁₀ and a gear G.
₁₆ , the gear G ₁₆ and the gear G ₁₉ , and the gear G ₁₇ and the gear G ₁₈ are always engaged.

According to this structure, since the shift gear G ₂ and the shift gear G ₄ are always meshed with each other as described above, the power of the input shaft 8 is reduced regardless of the speed change state of the PTO gear speed change mechanism 20. Are transmitted to the intermediate transmission shaft 17 via the shift gears G ₂ and G ₄ , and the input shaft 8 and the intermediate transmission shaft 17 are always driven in opposite directions. In this state, by operating the shift gears G ₁₁ , G ₁₂ or the shift gear G ₂₀ , the following three forward gear shifts and one reverse gear shift can be performed.

<First forward speed> When the shift gear G ₂₀ is shifted to the left and engaged with the gear G ₁₃ , the power of the input shaft 8 is shifted gear G ₂ → shift gear G ₄ → intermediate transmission shaft 17 → gear G ₁₃ → Shift gear G ₂₀ → gear G ₁₉ → gear G ₁₆ → gear G ₁₇
→ Gear G ₁₈ → Transmission is transmitted in the order of the output shaft 10 of the traveling system, and is taken out from the output shaft 10 of the traveling system as the first forward speed.

<Second forward speed> When the shift gear G ₁₁ is shifted to the right and engaged with the transmission gear G ₁₅ , the power of the input shaft 8 is shifted gear G ₂ → shift gear G ₄ → intermediate transmission shaft 17
→ Gear G ₁₅ → Shift gear G ₁₁ → Gear G ₁₀ → Gear G ₁₆ → Gear G ₁₇ → Gear G ₁₈ → Transmission system output shaft 10 is transmitted in the order, and the second forward speed is taken out from the travel system output shaft 10.

<3rd forward speed> When the shift gear G ₁₂ is shifted to the left and engaged with the transmission gear G ₁₄ , the power of the input shaft 8 is shifted gear G ₂ → shift gear G ₄ → intermediate transmission shaft 17
→ Transmission gear G ₁₄ → Shift gear G ₁₂ → Gear G ₁₀ → Gear G ₁₆
→ Gear G ₁₇ → Gear G ₁₈ → Transmission system output shaft 10 is occlusion transmitted in this order, and is taken out of the travel system output shaft 10 as the second forward speed.

<1st reverse speed> When the shift gear G ₂₀ is shifted to the right and engaged with the gear G ₉ , the power of the input shaft 8 is gear G ₉ → shift gear G ₂₀ → gear G ₁₉ → gear G ₁₆ → gear G
₁₇ → gear G ₁₈ → occlusal transmission in the order of traveling system output shaft 10,
The first reverse speed is taken out from the traveling system output shaft 10.

It should be noted that the shift gear G ₂₀ for switching "forward 1st speed-reverse 1st speed" and "forward 2nd speed-forward 3".
Wherein for switching fast "shift gear G _11, respectively engaged with the shift fork 31a on the G _12, the operating shaft 31 of the 32a is mounted on the upper rear portion of the transmission case 2, an operation shaft which is projected outside the case The left ends of 31, 32 are selected by the travel speed change lever 33 and pushed and pulled. The operation shafts 31 and 32 are restrained by the double meshing prevention mechanism 34 so that the simultaneous shift operation is not possible. The operation shafts 31 and 32 are provided with ball detent mechanisms 31b and 32b, respectively. The assembling holes 31b and 32b are machined from mutually orthogonal directions so as to coincide with the machining directions of the assembling holes of the ball detent mechanisms 23b and 24b in the PTO gear transmission 20. It is considered that the orientation of the work (mission case) in can be easily set.

Although not shown, "first forward speed-reverse first speed
The operating shaft 3 of the shift fork 31a for switching "speed"
If 1 is also projected to the right side of the mission case 2,
Between the pair of operating shafts 23, 24 for PTO gear shifting projecting to the right side of the mission case 2 and the rightward projecting end of the operating shaft 31, only when both operating shafts 23, 24 are in the neutral position, the operating shaft 31 is moved backward. Mechanism that allows operation to position, operation axis 31
Is operated to the reverse position, the operation shafts 23 and 24, which are operated to the drive position, are forcibly returned to the neutral position, and the PTO shaft 14 is moved.
To stop the drive of the PTO shaft 14 by operating one of the operation shafts 23 and 24 to drive the PTO shaft 14 only when the operation shaft 31 is not in the reverse position. It is easy to provide a so-called back tilling check mechanism such as a mechanism for returning the operation shaft 31 to the neutral position to stop traveling, or a mechanism combining these.

Next, the structure for selecting one-wheel traveling mode and two-wheel traveling mode will be described. [One-Wheel Running Mode] In this running mode, as shown in FIGS. 4A and 6, the first axle case 11 is directly bolted to the right side surface of the transmission case 2. This first
The axle case 11 is made up of a sheet metal mating case,
An input sprocket 37 is rotatably positioned and supported inside the upper end thereof, and an axle 38, which is partially protruded toward the center C of the machine body, is supported at a lower end of the case. An output sprocket 39 fixed to the axle 38 and the input sprocket 37 The chain 40 is wound around and attached. Then, by connecting the first axle case 11 to the transmission case 2, the traveling system output shaft 10 is connected to the input sprocket 3.
7 is fitted in the spline 7 to enable power transmission to the axle 38, and the single wheel 3 attached to the axle 38 positioned at the center C of the machine body is driven in an arbitrary speed change state.

When the first axle case 11 is removed from the transmission case 2, both ends of the boss portion of the input sprocket 37 are attached to a shallow cylindrical container-like bearing member 41 provided inside the case and a side surface of the case. It is supported by the formed opening 42 without falling into the case. Further, a thrust washer 43 is provided inside the bearing member 41 so as to receive the thrust load inward of the case of the input sprocket 37 spline-connected to the traveling system output shaft 10.

[Two-wheel running mode] In this running mode, as shown in FIG.
As shown in (b) and FIG. 7, the traveling output from the mission case 2 is transmitted to the second axle case 11 via an intermediate transmission case 12 bolted to the right side surface of the mission case 2 at two points. .

The intermediate transmission case 12 is formed of a metal sheet mating case, and an input side sprocket 50 and an output side sprocket 51 are provided inside both ends thereof, like the input sprocket 37 of the first axle case 11, and the thrust washer. The bearing members 54 and 55 incorporating the members 52 and 53 and the case openings 56 and 57 are used for positioning and support so that they can rotate freely, and a chain 58 is wound around and mounted on both sprockets 50 and 51.

The second axle case 11 is composed of a sheet metal mating case, and the input sprocket 60 is provided inside the upper end thereof.
However, similar to the input sprocket 37 of the first axle case 11, a bearing member 62 incorporating a thrust washer 61 is used.
And a case opening 63 are used for positioning so that the chain can freely rotate, and a lower end of the case supports an axle 64 projecting leftward and rightward, and a chain extending between the output sprocket 65 fixed to the axle 64 and the input sprocket 60. 66
Is wound around.

The output side end of the intermediate transmission case 12 and the input side end of the second axle case 11 having the above-described structure are positioned and connected as follows via a case support 2b extending forward from the transmission case 2. To be done. That is, a bearing member 67, which is configured as a separate component, is positioned and bolted to the case support portion 2b through the inlay portion 68, and an intermediate support shaft 69 is supported by the bearing member 67 penetrating left and right. ing. By connecting the intermediate transmission case 12 to the right side surface of the transmission case 2, the input side sprocket 50 is spline-fitted onto the traveling system output shaft 10, and the output side sprocket 51 is located at the right end of the intermediate support shaft 69. The second axle case 11 is mounted on the center C of the machine body and is fitted to the input sprocket 60 by spline-fitting the second axle case 11 along the left side surface of the case support portion 2b. Is splined on the left end of the intermediate support shaft 69. Therefore, by assembling the intermediate transmission case 12 and the second axle case 11 as described above, power can be transmitted from the traveling system output shaft 10 to the axle 64, and the pair of wheels 3, 3 mounted on the left and right sides of the axle 64. 3 can be driven. In this case, since the second axle case 11 is provided on the center C of the machine body, the left and right wheels 3, 3 can be distributed to the left and right from the center C of the machine body with a small gap, and stable even in a narrow ridge or groove bottom. You can drive well on two wheels. The second axle case 11 arranged on the center C of the machine body is
Is assembled by penetrating through the opening 70 formed in, and the edge of the opening 70 is reinforced by burring.

[Other Embodiments] The present invention can also be implemented in the following modes. Input side sprocket 5 in the intermediate transmission case 12
0 and the output side sprocket 51 are set to have different diameters, and both the sprockets 50 and 51 can be replaced with the traveling system output shaft 10 and the intermediate support shaft 69, respectively, and the input / output end of the intermediate transmission case 12 is configured. By reversing the gears, the intermediate transmission case 12 can be selectively used as the deceleration case or the speed increase case, and the traveling speed shift range can be further expanded. In the embodiment, the rotary cultivating work is exclusively performed, but it may be carried out in a form equipped with a hitch for connecting a non-driving type working device such as a ridger and a plow.

Incidentally, reference numerals are written in the claims for convenience of comparison with the drawings, but the present invention is not limited to the configuration of the attached drawings by the entry.

[Brief description of drawings]

FIG. 1 is a left side view in a one-wheel running mode.

FIG. 2 is a right side view in a single-wheel traveling mode.

FIG. 3 is a right side view in a two-wheel traveling mode.

FIG. 4 is a schematic plan view showing both traveling modes.

FIG. 5 is a developed cross-sectional view of the inside of the mission case.

FIG. 6 is a developed cross-sectional view showing a traveling system in a one-wheel traveling mode.

FIG. 7 is a developed horizontal cross-sectional view showing a traveling system in a two-wheel traveling mode.

FIG. 8 is a vertical sectional side view of the mission case.

FIG. 9 is a developed cross-sectional view of the mission case.

FIG. 10 is a vertical cross-sectional side view of the gear shift operation unit.

FIG. 11 is a cross-sectional view of the PTO clutch.

[Explanation of symbols]

8 1st shaft (input shaft) 10 3rd shaft (travel system output shaft) 14 PTO shaft 17 2nd shaft (intermediate speed change shaft) G _1, G ₂ shift gear G _3, G ₄ shift gear G _5, G ₆ speed change gear

Claims (2)

[Claims] 1. A plurality of shift gears (G) of a PTO gear speed change mechanism (20) spline-fitted and attached to a first shaft (8).
_1, G ₂ ) is operated to shift so that the plurality of speed change gears (G _5, G ₆ ) supported by the third shaft (10) can be selectively engaged, and the second shaft (17) is spline-fitted. Wearing P
A plurality of other shift gears (G _3,
G ₄ ) is shifted to operate the plurality of transmission gears (G
_5, G ₆ ) is configured to be selectively occlusable, and these two sets of shift gears (G _1, G ₂ ) and (G _3, G ₄ ) are always occluded regardless of the shift state, and the first axis ( 8) and the second axis (1
7) and 7) are rotationally driven in mutually opposite directions, and one of the two sets of shift gears (G _1, G ₂ ) and (G _3, G ₄ ) is selectively used as the speed change gear (G _5, G ₆ ). be to bite into, the transmission gear (G _5, G ₆₎ to the interlocked linked PTO shaft (14) forward and respectively speed drive configured to be able to reverse direction, the first axis (8) and a second The walking type management machine is characterized in that the forward rotation power and the reverse rotation power from the shaft (17) are respectively input to the traveling system gear transmission mechanism (21) to perform multi-stage gear shifting including the reverse gear. Gear shifting structure. 2. The first shaft (8) is an input shaft for receiving engine power, the second shaft (17) is an intermediate speed changing shaft, and the third shaft (10) is a traveling system output shaft. Claim 1
The shift structure of the walk-type management machine described.