JPH0821516A - Counter gear - Google Patents

Abstract

PURPOSE:To make small the gear sound of counter gears to transmit motive power to the speed shift main shaft of a transmission from the PTO shaft of an engine and prevent the increase of gear width, in the case of a walking rice planting machine. CONSTITUTION:A synthetic resin rear 27b is made to mesh with the gear 25 of the PTO shaft 23 of an engine 2, and a hard steel gear 27a is made to mesh with the gear 29 of the speed shift main shaft 24 of a transmission, and the gear 27b is integrally coupled to the gear 27a, and the gear 27a to form the shaft-support portion of the tip of a shaft 26 is made to fit to the tip portion of the shaft 26 of a hydraulic pump 71. Thus, the gear 27b is rotated by meshing with the gear 25 at a high peripheral speed, and the gear 27a is rotated by meshing with the gear 29 at a low peripheral speed and high torque.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paddy field working machine such as a walk type rice transplanter, and more particularly to a counter gear for transmitting power from an engine to a transmission in the paddy field working machine.

[0002]

2. Description of the Related Art Conventionally, in a walk-behind rice transplanter, a counter gear for transmitting power from an engine to a transmission is a two-stage reduction gear consisting of a large gear and a small gear, which are integrally formed of steel. The rotation speed of the engine that was rotating was greatly reduced and transmitted to the transmission so that the wheel speed would match the walking speed.

[0003]

However, since the large gear, which is the first reduction gear, has a high peripheral speed, the gear noise may be high. Also, in order to reduce the gear noise,
If the counter gear is made of synthetic resin, there is a possibility that durability problems may occur especially in the small gear on which a large torque acts.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a counter gear in which the generation of noise is improved while maintaining the durability, and thus the above-mentioned problems are solved.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and is a counter gear for transmitting power from an engine (2) to a transmission (T), the counter gear (27). ) Has a large gear (27b) and a small gear (27a) integrally connected, and the large gear (27b) is made of synthetic resin, and the small gear (27a)
Is made of metal.

[0006]

[Function] Based on the above construction, the large gear (2
7b) rotates by meshing with a gear (25) attached to the PTO shaft (23) of the engine (2),
A small gear wheel (27a) made of metal integrally connected with b) meshes with a gear wheel (29) mounted on the transmission main shaft (24) of the transmission (T) to rotate.

[0007]

As described above, according to the present invention, since the large gear (27b) made of synthetic resin rotates at a high peripheral speed, the gear noise of the large gear (27b) can be reduced. Further, since the small gear (27a) made of metal meshes with the gear (29) of the transmission main shaft (24) at a low peripheral speed to rotate, the torque of the small gear (27a) becomes large, but since it is made of metal, It is possible to prevent the width from increasing.

The reference numerals in the parentheses are for the purpose of contrasting with the drawings and do not limit the structure of the invention.

[0009]

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

As shown in FIG. 9, the walking type rice transplanter 1 has a body 6 composed of an engine 2, a transmission case 3, a frame 5, and the like.
, The seedling stand 9 is slidably supported in the left-right direction, and the planter 10 is arranged at the lower end portion of the seedling stand 9. Further, a float 11 is suspended below the frame 5 so as to be swingable around a rear swing fulcrum 11a, and the float 11 detects the earth pressure of the paddy field to detect the height of the machine. It constitutes the detection mechanism. An output shaft 12 is provided so as to project from the left and right sides of the mission case 3, and a chain case 13 is supported so as to be swingable about the output shaft, and a paddy wheel 15 is provided at the tip of these chain cases. It is supported.

The engine 2 in front of the machine body 6
A hydraulic cylinder 19 for adjusting the height of the machine body is disposed between the bracket 16 fixed to the vehicle and the bumper member 17 fixed to the mission case 3. The hydraulic cylinder 1
9 is a movable cylinder type, and its rod 19a is fixed to the bracket 16 and the bumper member 17, and the cylinder 19b reciprocates up and down by being guided by the rod 19a. Further, a balance arm 20 is swingably connected to the cylinder 19b around a pin, and both ends of the balance arm are fixed to the base end of the swing chain case 13 via rods 21, respectively. Arm 13a
Connected to. Further, one shift operation lever 22 extends rearward from the mission case 3.

On the other hand, as shown in FIGS. 6 to 8, a transmission T is disposed below the engine 2.
3 is the mission case. Engine 2 PTO
Power from the shaft 23 is transmitted to the transmission main shaft 24 in the transmission case 3 via a gear 25, a gear 27 a supported by the shaft 26, a gear 27 b integral with the gear, and a gear 29 fixed to the transmission main shaft 24. I have. The PTO shaft 23, the gear 25, the gears 27b and 27a, the shaft 26, the gear 29, and the transmission main shaft 24 constitute a power transmission device G (see FIG. 1) from the engine 2 to the transmission T. A planter drive shaft 30 is rotatably supported adjacent to the transmission main shaft 24, and a counter shaft 31 is rotatably supported adjacent to the other transmission main shaft 24. Furthermore, the axle case 3 is attached to the front end of the mission case 3.
2, 32 are fixed, and the axle cases 32, 3
2 is a cylindrical portion 13b, 1 of the chain case 13, 13
3b is swingably inserted and fitted. The left and right output shafts 12, 12 are attached to the axle cases 32, 32.
Is supported by a chain case 13 from a sprocket 33 fixed to the tip of the output shaft 12 via a chain.
The power is transmitted to the wheels 15 supported by the axle. The mission case 3 includes the counter shaft 3
A planter intermediate shaft 35 is rotatably supported side by side with 1.

Further, inter-shift gears A and B comprising shift gears are fixed to the planter drive shaft 30, and a shift gear body 36 slides on the shift main shaft 24 so as to be selectively meshable with the inter-shift gears A and B. The gear body 36 has a narrow gear C and a wide gear D formed thereon. The counter shaft 31 has a small gear 37 and a large gear 3.
9, the output shafts 12, 12 are provided with side clutches 40, 40, and these side clutches 40, 40 have a final gear 41 supported on the output shafts 12, 12 on the left and right. Either one of the output shafts 12, 12 or both of the output shafts 12 can be engaged with each other. A reverse gear body 42 is slidably and rotatably mounted on the planter intermediate shaft 35, and a planter clutch 43 is slidably mounted on the planter intermediate shaft 35. Shaft 45 case 3
A sprocket 46 is fixed to the outer end of the shaft, and the planter clutch 43 can move the hollow shaft 45 and the planter intermediate shaft 35 toward and away from each other. The reverse gear body 42 includes a large gear 42b and a small gear 42c, and the large gear 42b is always meshed with the narrow gear C of the transmission gear body 36,
The position where the large gear 42b meshes with the final gear 41 and the position where the small gear 42c meshes with the large gear 39 are switched. The sprocket 46 and the sprocket 47 provided at the end of the planter drive shaft 30 are combined with the chain 4.
9, and a sprocket 50 for transmitting power to a planting device such as the planter 10 is attached to the left end of the planter intermediate shaft 35.

As shown in FIG. 7, a screw shaft 51 extends in the left-right direction and is rotatably supported at the rear upper portion of the transmission case 3. A slide block 52 slides on the screw shaft 51. Only movement is screwed freely. Further, power is transmitted to the screw shaft 51 from the planter intermediate shaft 35 via the sprocket 53, the chain 55, and the sprocket 56, and the slide block 52 reciprocates within a constant stroke based on the rotation of the screw shaft 51. Then, as shown in FIG. 8, the slide block 52 has a first swing arm 59 fixed to the front end of the lower rotary shaft 57.
Connected to. As shown in FIG. 9, the rotating shaft 57 extends along the lateral side of the frame 5 in the front-rear direction of the machine and is rotatably supported, and the rear end of the rotating shaft 57 has a second swinging motion. The moving arm 60 is fixed, and the seedling stand 9 is connected to the tip of the arm 60. Therefore, the reciprocating motion of the slide block 52 based on the rotation of the screw shaft 51 causes the seedling rest 9 to reciprocate left and right via the first swing arm 59, the rotating shaft 57 and the second swing arm 60. Have been.

Next, the operating device for the traveling transmission and the inter-stock transmission will be described with reference to FIGS. One shift operation lever 22 extending rearward from the mission case 3 has a base portion 22a that is axially supported by the case 3 so as to be rotatable. As shown in FIG. 9, the gear shift operation lever 22 has a tip portion 22b bent upward, and the tip portion 22b has an arc-shaped guide groove 61a of a guide member 61 as shown in FIG. The base portion 22a is pivotally operated in the forward and reverse directions. An arm 62 is fixed to the base 22a in the transmission case 3, and a pin 63 is implanted at a tip of the arm 62. On the other hand, mission case 3
Is formed with a guide hole 65 that penetrates in the left-right direction of the machine body.
One shifter shaft 66 having a shaft is slidably supported, and a detent device 70 including a ball and a spring is arranged at a portion facing the guide hole 65. The detent device 70 allows the shifter shaft 66 to be provided at six positions. Be positioned at. An L-shaped plate 67 is fixed to one end of the shifter shaft 66, and a long hole 67a is formed at the tip of the plate. The pin 63 fits into the long hole 67a. I agree. Further, a shifter arm 69 is fixed to the other end of the shifter shaft 66, the shifter arm 69 has two engaging grooves 69a and 69b formed at the front end thereof, and the one engaging groove 69a is formed in the shift gear. Engagement with the engagement groove 36a (see FIG. 6) of the body 36 and the other engagement groove 69
b is engaged with the engagement groove 42a of the reverse rotation gear body 42. Therefore, the shifter shaft 66, the plate 67, and the shifter arm 69 are integrally formed, and constitute one shifter that is supported by the guide hole (guide member) 65 and slides in the axial direction. As shown in FIG. 5, the speed change operation lever 22 moves along the guide groove 61a of the guide plate 61 in the second forward speed F2 (road running speed), the first forward speed F1 (working speed), the neutral N, and the reverse R. At the first forward speed F1, and further at the small, large, and middle positions between the stocks.

Next, referring to FIG. 1 and FIG. 2 in which an input portion from the engine 2 in FIG. 6 is enlarged, a PTO shaft 23, a gear 2
7a and 27b and the hydraulic pump 71 will be described in detail. The transmission case 3 is divided substantially at the center, and 3a shown in FIG. A case cover 3b is oil-tightly attached to the left transmission case 3a,
A hydraulic pump 71 is oil-tightly mounted on the case lid 3b.

The PTO shaft 23 of the engine 2 is supported by a crankcase of the engine 2 fixed to the case 3a and a bearing hole 72 of the case lid 3b.
A gear 25 is attached to the O-axis 23 so that it can be moved only in the axial direction by a key or the like.
Are mounted, and the boss end 25a of the gear 25 on the case 3a side is inserted into the hole 73 of the case 3a.

The tip 8 of the shaft 26 of the hydraulic pump 71
The gear 27a is engaged with the gear 27a while being prevented from rotating, and the boss end 75 of the gear 27a is pivotally supported in the bearing hole 76 of the case 3a.

Further, as shown in FIG. 2, a gear 2 made of hard steel is used.
An intermediate boss 77 of 7a is formed in a square (sharpened), and a square hole 79 of a synthetic resin gear 27b with a corner removed is press-fitted into the intermediate boss 77 to form a gear 27a.
And 27b are integrally formed. Note that, as described above, the boss end 75 is formed in a cylindrical shape, and
Is rotatably supported in the bearing hole 76. 2 (d) and (e)
As shown in, the gear portion of the gear 27a is widened, the right gear head is cut to form the low gear portion 82, and the gear-shaped hole 83 of the gear 27b is press-fitted and fixed by fitting.
The gears 27a and 27b may be integrally formed. Also,
Generally, the press-fitting / fitting portion may be bonded.

Next, from the engine 2 to the transmission case 3
Describing the power transmission action to the engine 2, when the engine 2 rotates, the shaft 23 rotates, the gear 27b rotates via the gear 25 stopped by a key or the like, and the gear 27b is rotated by the square hole 79 of the gear 27b. The rotation of the engine 2 is transmitted to the inside of the mission case 3 by rotating and rotating the transmission main shaft 24 via the gear 29. And gear 2
When the 7a rotates, the rotation of the tip portion 81 of the shaft 26 is transmitted from the rotation stop hole 80 of the gear 27a, and the hydraulic pump 71 operates in accordance with the rotation of the shaft 26.

The engine 2 and the case 3a are detached from each other, and the engine 2 together with the PTO shaft 23 is removed from the gear 25 as shown in FIG.
The engine 2 can be removed from the case 3a by moving to the right in. At this time, since the gear 25 is engaged with the case 3a by the boss end 25a and maintains an almost assembled state, when the engine 2 is mounted on the case 3a, the PTO shaft 23 is easily inserted into the gear 25, The engine 2 can be easily attached to and detached from the case 3a.
To make maintenance easier. Also, the PTO shaft 23 is
Since both ends are supported by the b and the crankcase of the engine 2, the strength of the PTO shaft 23 can be improved.

The pump shaft 26 has its base end supported by the pump case, and its tip end supported by the bearing hole 76 of the transmission case 3a via the boss end 75 of the gear 27a. While improving strength,
The durability of the bearing of the pump shaft 26 can be improved.

A first-stage synthetic resin gear 27b, which forms a two-stage reduction gear, meshes with a gear 25 attached to the PTO shaft 23 of the engine 2 at a high peripheral speed, and is integrated with the gear 27b to form a two-stage hard. Since the steel gear 27a meshes with the gear 29 at a low peripheral speed and a high torque, gear noise generated between the gear 25 and the gear 27b meshing at a high peripheral speed can be reduced. Further, it is possible to prevent the tooth width of the gear 27a from increasing with respect to the gear 29 that meshes with high torque.

Next, the gear shifting operation will be described with reference to FIGS. 3 to 6. In the forward second speed (road surface speed) F2, the lever 22 is set to the F2 position of the guide plate 61. The gear C of the speed change gear body 36 meshes with the large gear 42b of the reverse rotation gear body 42, and the large gear 42b of the reverse rotation gear body 42 meshes with the final gear 41. The side clutch 40 is the output shaft 12
, The rotational force transmitted from the PTO shaft 23 to the transmission main shaft 24 is applied to the gear C and the large gear 42 of the reverse rotation gear body 42.
b, to the output shaft 12 via the final gear 41 and the side clutch 40. Although the counter shaft 31 is rotated by the final gear 41 and the small gear 37, since the large gear 39 and the gear D are not meshed with each other, the counter shaft 31 simply idles without any problem. Further, the planter drive shaft 30 is rotated by the engagement of the gears B and D, and the sprocket 47,
Hollow shaft 45 through chain 49 and sprocket 46
Rotates, but since the planter clutch 43 is disengaged, the planter intermediate shaft 35 does not rotate, and the planting device such as the planter 10 does not operate.

First speed forward (planting traveling speed stage) F1 When the speed change operation lever 22 is in the F1 region of the guide plate 61, the gear D of the speed change gear body 36 is formed to be wide, so that the gear is always set to the first speed. The gear D is engaged with the gear D, the large gear 39, the counter shaft 31, the small gear 3 and the rotational force transmitted from the PTO shaft 23 to the speed change main shaft 24.
The planted traveling speed is transmitted to the output shaft 12 via the 7, final gear 41, and the side clutch 40.

When the operating lever 22 is set at a small position between the stocks, the rotational force of the transmission main shaft 24 is transmitted to the planter drive shaft 30 via the gears D and B of the transmission gear body 36, and the small rotation The speed is transmitted to the planter intermediate shaft 35 via the sprocket 47, the chain 49, the sprocket 46, the hollow shaft 45, and the planter clutch 43.

When the operating lever 22 is set at a large position between the stocks, the rotational force is transmitted to the planter drive shaft 30 via the gears C and A, and the large rotational speed is transmitted to the planter intermediate shaft 35. .

When the operating lever 22 is set to the middle position between the stocks, the rotational force is transmitted to the planter drive shaft 30 via the gear C and the gear B, and the middle rotational speed is transmitted to the planter intermediate shaft 35. It

That is, the planting traveling speed is formed in one speed stage, but through the planter drive shaft 30, the sprocket 47, the chain 49, the sprocket 46, the hollow shaft 45, the planter clutch 43, and the planter intermediate shaft 35. The planter 10 is rotated from the sprocket 50 at small, large, and medium rotation speeds, and the stock spacing is adjusted to large and small.

Neutral speed stage N When the shift operation lever 22 is set to the position N, the engagement between the gear D and the gear 39 of the shift gear body 36 is cut off and the output shaft 1
The rotation force to 2 is not transmitted.

When the shift operation lever 22 is set to the position R, the transmission of the rotational force from the gears C and D of the transmission gear body 36 to the gear 39 is cut off, and the rotation of the transmission main shaft 24 is changed to the gear C and the reverse gear. Low-speed reverse rotation is transmitted to the output shaft 12 via the large gear 42b and the small gear 42c of the body 42, the large gear 39, the counter shaft 31, the small gear 37, the final gear 41, and the side clutch 40.

When the above-described running and shifting between stocks are performed, the shift operating lever 22 has an arc-shaped guide groove 61a.
, The base shaft portion 22a is rotated forward and backward. As a result, the arm 62 fixed to the shaft 22a swings in the left-right direction, and the pin 63 at the tip of the arm 62 fits into the long hole 67a of the plate 67, thereby integrally fixing the plate 67. Guide shaft 65
Guided by and slide to the left and right. Further, the shifter shaft 66 has the detent device 7 in its detent groove 66a.
When the ball of 0 is fitted, the ball is positioned at a predetermined position, and the shifter arm 69 integrally fixed to the shifter shaft 66 is slid in the axial direction. Then, one of the engagement grooves 69a formed in the shifter arm 69 engages with the engagement groove 36a of the transmission gear body 36 to move the gear body in the axial direction to selectively mesh the gears D and C, The other engagement groove 69b engages with the engagement groove 42a of the reverse rotation gear body 42,
The gears 42b and 42c are moved in the axial direction to selectively engage with each other.

Although the walk-behind rice transplanter has been described above, the present invention is not limited to this.
Needless to say, the present invention can be similarly applied to other paddy field working machines such as a submerged direct sowing machine.

[Brief description of drawings]

FIG. 1 is an enlarged sectional view in which a part of a transmission according to the present invention is enlarged.

2A is a perspective view of a counter gear, FIG. 2B is a sectional side view thereof, FIG. 2C is a rear view of the small gear, and FIG. 2D is a sectional side view showing another embodiment of the counter gear. (E) is a rear view of the small gear.

FIG. 3 is a partial side view showing the shift operation position.

FIG. 4 is a front view thereof.

FIG. 5 is a front view showing a guide member of the speed change operation lever.

FIG. 6 is a sectional development view showing the entire transmission to which the present invention is applied.

FIG. 7 is a sectional front view showing the screw shaft portion.

FIG. 8 is a side view showing the transmission.

FIG. 9 is an overall side view of the walking rice transplanter.

[Explanation of symbols]

 2 engine T transmission 23 PTO shaft 24 transmission main shaft 25 gear 27 counter gear 27a small gear (gear) 27b large gear (gear) 29 gear

Claims (1)

[Claims] 1. A counter gear for transmitting power from an engine to a transmission, wherein the counter gear has a large gear and a small gear integrally connected, and the large gear is made of synthetic resin, and the small gear is made of metal. Counter gear, characterized by being made.