JPH059218U - Counter gear - Google Patents

Abstract

(57) [Abstract] [Purpose] In a rice transplanter for walking, to reduce the gear noise of the counter gear that transmits power from the PTO shaft of the engine to the transmission main shaft of the transmission, and to prevent an increase in the gear width. [Structure] A gear 27b made of a synthetic resin is meshed with a gear 25 of a PTO shaft 23 of an engine 2. Then, a gear 27a made of hard steel is meshed with the gear 29 of the transmission main shaft 24 of the mission 3. Then, the gear 27a is integrally connected to the gear 27a,
The gear 27a forming the bearing portion at the tip of the shaft 26 is fitted to the tip of the shaft 26 of the hydraulic pump 71. Thus, the gear 27b rotates in mesh with the gear 25 at a high peripheral speed, and the gear 27a rotates in mesh with the gear 29 at a low peripheral speed and high torque.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a paddy field working machine such as a walk-behind 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]

[Prior Art]

 Conventionally, in a walk-behind rice transplanter, the counter gear that transmits the power from the engine to the transmission is a two-stage deceleration gear consisting of a large gear and a small gear that are integrally made of steel, and rotate at high speed. The engine rotation speed is being significantly reduced and transmitted to the trans mission so that the wheel speed matches the walking speed.

[0003]

[Problems to be solved by the device]

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

Therefore, an object of the present invention is to provide a counter gear that improves noise generation while maintaining durability, and thus solves the above-mentioned problems.

[0005]

[Means for Solving the Problems]

 The present invention has been made in view of the above circumstances, and in a counter gear that transmits the power from the engine (2) to the transmission (T), the counter gear (27) is integrally coupled. It has a gear (27b) and a small gear (27a), the large gear (27b) is made of synthetic resin, and the small gear (27a) is made of metal.

[0006]

Based on the above configuration, the large gear (27b) made of synthetic resin meshes with the gear (25) attached to the PTO shaft (23) of the engine (2) to rotate, and the large gear (27b) ) And a small gear (27a) made of metal integrally connected to the gear (29) rotate by meshing with a gear (29) mounted on the transmission main shaft (24) of the transmission (T).

[0007]

[Effect of the device]

 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 metal small gear (27a) rotates at a low peripheral speed by meshing with the gear (29) of the transmission main shaft (24), the small gear (27a) has a large torque, but is made of metal. It is possible to prevent an increase in tooth width.

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

[0009]

【Example】

 Hereinafter, embodiments according to the present invention will be described with reference to the drawings.

As shown in FIG. 9, the walk-behind rice transplanter 1 has a machine body 6 including an engine 2, a mission case 3, a frame 5 and the like, and a handle 7 is provided behind the machine body 6. In addition, a seedling stand 9 is slidably supported in the left-right direction, and a planter 10 is arranged at a lower end portion of the seedling stand 9. Further, below the frame 5, a float 11 is suspended so as to be swingable around a rear swing fulcrum 11a, and the float 11 detects the earth pressure on the paddy field to detect the height of the machine. The detection mechanism is configured. 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.

A hydraulic cylinder 19 for adjusting the height of the machine body is provided between the bracket 16 fixed to the engine 2 and the bumper member 17 fixed to the mission case 3 in front of the machine body 6. There is. The hydraulic cylinder 19 is of a movable cylinder type, the rod 19a of which 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 about 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. Is connected to the arm 13a. 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 1 is arranged below the engine 2. 3 is the mission case. The power from the PTO shaft 23 of the engine 2 is transmitted through the gear 25, the gear 27a supported by the shaft 26, the gear 27b integrated with the gear 27, and the gear 29 fixed to the transmission main shaft 24 to change the speed in the transmission case 3. It is transmitted to the main shaft 24. 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 of the transmission main shaft 24. Further, axle cases 32, 32 are fixed to the front end of the transmission case 3, and the cylinder portions 13b, 13b of the chain cases 13, 13 are swingably inserted and fitted into the axle cases 32, 32. Has been done. The left and right output shafts 12, 12 are rotatably supported by the axle cases 32, 32. The sprocket 33 fixed to the tip of the output shaft 12 is supported by the axle on the chain case 13 via the chain. The power is transmitted to the wheels 15. A planter intermediate shaft 35 is rotatably supported by the mission case 3 along with the counter shaft 31.

Inter-stock transmission gears A and B, which are shift gears, are fixed to the planter drive shaft 30, and a transmission gear body 36 slides on the transmission main shaft 24 so as to be selectively meshed with the inter-stock transmission gears A and B. A narrow gear C and a wide gear D are formed on the gear body 36 so as to be freely movable. Further, a small gear 37 and a large gear 39 are fixedly mounted on the counter shaft 31, and side clutches 40, 40 are provided on the output shafts 12, 12, respectively. The final gear 41 rotatably supported by the output shafts 12, 12 is configured to be able to mesh with either or both of the left and right output shafts 12, 12. A reverse rotation gear 42 is slidably and rotatably attached to the planter intermediate shaft 35, and a planter clutch 43 is slidably attached to the planter intermediate shaft 35. A sprocket 46 is fixed to the outer end of the hollow shaft 45 of the case 3, and the planter clutch 43 can contact and separate the hollow shaft 45 and the planter intermediate shaft 35. The reverse rotation gear body 42 includes a large gear 42b and a small gear 42c. The large gear 42b always meshes with the narrow gear C of the variable speed gear body 36, and the large gear 42b meshes with the final gear 41. The position is switched to a position where the small gear 42c meshes with the large gear 39. The sprocket 46 and a sprocket 47 provided at the end of the planter drive shaft 30 are connected via a chain 49, and the left end of the planter intermediate shaft 35 transmits power to a planting device such as the planter 10. A sprocket 50 is attached.

Further, as shown in FIG. 7, a screw shaft 51 extending in the left-right width direction is rotatably supported in the upper rear part of the transmission case 3, and the slide block 52 is attached to the screw shaft 51. Is screwed so that it can slide only. Further, the screw shaft 51 is power-transmitted 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 is connected to a first swing arm 59 fixed to the front end portion of the lower rotary shaft 57. As shown in FIG. 9, the rotary shaft 57 extends in the longitudinal direction along the side of the frame 5 and is rotatably supported, and the rear end of the rotary shaft 57 has a second swing. The 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 stand 9 to move back and forth through the first swing arm 59, the rotation shaft 57, and the second swing arm 60. It is configured.

Next, the travel transmission device and the operating device for the inter-stock transmission device will be described with reference to FIGS. 3 and 4. One shift operation lever 22 extending rearward from the mission case 3 has a shaft portion at its base 22a and is rotatably supported by the case 3. 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 the guide member 61, as shown in FIG. The base 22a is operated to swing forward and backward. An arm 62 is fixed to the base 22a in the mission case 3, and a pin 63 is planted at the tip of the arm 62. On the other hand, the mission case 3 is formed with a guide hole 65 penetrating in the left-right direction of the machine body, and a single shifter shaft 66 having many detent grooves 66a ... Is slidably supported in the guide hole 65. At the same time, a detent device 70 including a ball and a spring is arranged at a portion facing the guide hole 65, and the detent device 70 positions the shifter shafts 66 at six positions. An L-shaped bent 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, and the pin 63 is fitted into the long hole 67a. It fits. 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 one of the engaging grooves 69a is the shift gear. The engaging groove 36a (see FIG. 6) of the ear body 36 is engaged, and the other engaging groove 69b is engaged with the engaging 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 are supported by the guide hole (guide member) 65 to form one shifter that slides in the axial direction. As shown in FIG. 5, the gear shift operation lever 22 moves along the guide groove 61a of the guide plate 61 along the second forward speed F2 (road surface traveling speed), the first forward speed F1 (working speed), the neutral N and the reverse R. And the small, large, and medium positions between stocks in the first forward speed F1.

Next, the PTO shaft 23, the gears 27a and 27b, and the hydraulic pump 71 will be described in detail with reference to FIGS. 1 and 2 in which the input portion from the engine 2 in FIG. 6 is enlarged. Are divided at almost the center, and 3a shown in FIG. 1 is the left side mission case of the mission case 3. A case lid 3b is oil-tightly attached to the left transmission case 3a, and an oil pressure pump 71 is oil-tightly attached to the case lid 3b.

The PTO shaft 23 of the engine 2 is axially supported by the crankcase of the engine 2 fixed to the case 3a and the bearing hole 72 of the case lid 3b, and the PTO shaft 23 is axially supported by a key or the like. Only the gear 25 is movably attached, and the boss end 25a of the gear 25 on the case 3a side is inserted into the hole 73 of the case 3a.

Further, the gear 27a is fixed to the tip portion 81 of the shaft 26 of the hydraulic pump 71 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. There is.

Further, as shown in FIG. 2, the intermediate boss 77 of the hard steel gear 27 a is formed in a square shape (cornered), and the intermediate boss 77 has no corner of the synthetic resin gear 27 b. A square hole 79 which is closed is press-fitted to integrally form the gears 27a and 27b. In addition, as described above, the boss end 75 is formed in a cylindrical shape and is pivotally supported in the bearing hole 76 of the case 3a. As shown in FIGS. 2 (d) and 2 (e), the gear portion of the gear 27a is widened, and the gear head on the right side thereof is cut to form the lower gear portion 82. The gears 27a and 27b may be integrally formed by press-fitting the holes 83 and fitting and fixing the holes. Further, generally, the press-fitting / fitting portion may be adhered.

Next, the power transmission operation from the engine 2 to the transmission case 3 will be described. When the engine 2 rotates, the shaft 23 rotates, and the gear 27b is rotated through the gear 25 that is stopped by a key or the like. Is rotated, the gear 27b is rotated by the square hole 79 of the gear 27b, and the rotation of the engine 2 is transmitted to the transmission case 3 by rotating the transmission main shaft 24 via the gear 29. When the gear 27a 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 can be removed from the case 3a by dismounting the engine 2 from the case 3a and moving the engine 2 together with the PTO shaft 23 from the gear 25 to the right in FIG. At this time, since the gear 25 is engaged with the case 3a by the boss end 25a and is maintained in a substantially assembled state, the PTO shaft 23 can be easily inserted into the gear 25 when the engine 2 is attached to the case 3a. The engine 2 can be easily attached to and detached from the case 3a, which facilitates maintenance of the engine 2. Further, since both ends of the PTO shaft 23 are supported by the case lid 3b 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 through the end 75 of the gear 27a. Of the pump shaft 26 and the durability of the bearing portion of the pump shaft 26 can be improved.

Further, the gear 25 attached to the PTO shaft 23 of the engine 2 is meshed with the gear 27b on the first stage, which is a two-stage reduction gear, at a high peripheral speed, and is integrated with the gear 27b to form a hard gear on the second stage. 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 shift operation will be described with reference to FIGS. 3 to 6. In the first forward speed (road surface speed) F2, the lever 22 is set to the F 2 position of the guide plate 61. The gear c of the transmission 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. When the side clutch 40 is connected to the output shaft 12, the rotational force transmitted from the PTO shaft 23 to the transmission main shaft 24 is output via the gear c, the large gear 42b of the reverse gear 42, the final gear 41, and the side clutch 40. It is transmitted to the shaft 12. 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 may be idle and there is no problem. Further, the planter drive shaft 30 is rotated by the meshing of the gears B and D, and the hollow shaft 45 is further rotated through the sprocket 47, the chain 49 and the sprocket 46, but the planter latch 43 is cut off. The intermediate shaft 35 does not rotate, and the planting device such as the plant 10 does not operate.

First forward speed (planted traveling speed stage) F1 When the gear shift operation lever 22 is in the F1 region of the guide plate 61, the gear D of the gear shift gear 36 is always formed to have a wide width. The gear D is meshed with the gear 39, and the rotational force transmitted from the PTO shaft 23 to the transmission main shaft 24 is transmitted to the gear D, the large gear 39, the counter shaft 31, the small gear 37, the final gear 41, and the side clutch 40. The planted traveling speed is transmitted via the output shaft 12.

Then, when the operating lever 22 is set to 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 gear D and the gear B of the transmission gear body 36, and the planter drive shaft 30 is further reduced. The rotation 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 to the large position between the stocks, the rotational force is transmitted to the planter drive shaft 30 via the gear C and the gear A, and the large rotational speed is transmitted to the planter intermediate shaft 35. It

When the operation 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 rotation speed is transmitted to the planter middle shaft 35. To be done.

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. Then, 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 gear D of the shift gear body 36 and the gear 39 are disengaged from each other, and the rotational force to the output shaft 12 is not transmitted.

Reverse speed R When the speed change operation lever 22 is set to the position R, the rotational force transmission from the gears C and D of the speed change gear body 36 to the gear 39 is cut off, and the rotation of the speed change 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.

Then, during the above-described running and shifting between stocks, the shift operating lever 22 is operated along the arc-shaped guide groove 61a, and the base end shaft portion 22a thereof is rotated forward and backward. As a result, the arm 62 fixed to the shaft portion 22a swings in the left-right direction, and the pin 63 at the tip of the arm 62 is fitted into the long hole 67a of the plate 67, so that the plate 67 is integrated. The shifter shaft 66, which is fixed to, is guided by the guide hole 65 and slides in the left-right direction. Further, the shifter shaft 66 is positioned at a predetermined position by fitting the ball of the detent device 70 in the detent groove 66a, and the shifter arm 69 integrally fixed to the shifter shaft 66 is axially moved. To slide. Then, one of the engagement grooves 69a formed in the shifter arm 69 engages with the engagement groove 36a of the speed change gear body 36 to move the gear body in the axial direction to selectively engage the gears D and C with each other. The other engaging groove 69b engages with the engaging groove 42a of the reverse rotation gear body 42, and the gears 42b and 42c are moved in the axial direction to be selectively meshed.

Although the walk-behind rice transplanter has been described above, the present invention is not limited to this, and it is needless to say that the present invention can be similarly applied to other paddy field working machines such as a riding-type rice transplanter and a submerged direct seeder. It is a theory.

[Brief description of drawings]

FIG. 1 is an enlarged cross-sectional view showing an enlarged part of a transmission according to the present invention.

2A is a perspective view of a counter gear, FIG. 2B is a sectional side view of the counter gear, FIG. 2C is a rear view of a small gear thereof, and FIG. 2D is a sectional side view of another embodiment of the counter gear. , (E) is the back 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 shift 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 a walk-behind 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 for utility model registration 1. A counter gear for transmitting motive power from an engine to a transmission, the counter gear having a large gear and a small gear integrally connected, and combining the large gear. A counter gear, characterized in that it is made of resin and the pinion gear is made of metal.