JPH08334164A - Scissors gear of rotary case - Google Patents

Abstract

PURPOSE: To form a clearance between addenda on a gear marginal part and to prevent contact of the addenda with each other by forming only inside margins of the adjoining addenda of a main gear and a sub gear in tapered surfaces. CONSTITUTION: Marginal parts of addenda of main gears 31a, 28a and sub gears 31b, 28b of a planetary gear 31 and an intermediate gear 28 are formed in tapered surfaces 31a', 31b', 28a' and 28b' only on their inside surfaces. Consequently, contact of the addenda of the gears with each other is eliminated without lowering strength of the addenda of the gears. Accordingly, as a spacer is eliminated and the gears make contact with each other and support each other, the gears never fall. Additionally, as the main gears 31a, 28a are formed thicker than the sub gears 31b, 28b, transmission efficiency of the gears is good.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scissors gear of a rotary case used for a transmission system of a planting device of a rice transplanter.

[0002]

2. Description of the Related Art A transmission mechanism in a rotary case of a rice transplanter, which uses a scissors gear to remove backlash caused by gear backlash or the like, has been conventionally known. Specifically, as shown in FIGS. 9 and 10,
Each of the planetary gear (100) and the intermediate gear (101) includes a main gear (100a) (101a) and a sub gear (100a).
b) (101b), the spring (102) is stretched between both gears (100a) (100b) of the planetary gear (100), and one gear (100a) is attached to the rotary case (1).
03) in the rotation direction, and the other gear (100b) is delayed in the rotation direction of the rotary case.

As shown in FIG. 10, pins (104) and (105) of different lengths are planted on the side surfaces of the main gear (100a) and the sub gear (100b) in the planetary gear (100), and these pins (104) ) (105) between the spring (10
2) is stretched and the pin (10) of the main gear (100a) is
4) is an elongated hole (10) formed in the sub gear (100b).
6) The inside can be slid. In addition, in order to prevent the main gear and the sub gear from interfering with each other, a spacer (107) is interposed.

[0004]

According to the above,
Since the main gear and the sub gear are separated by the amount of the spacer interposed, the gears fall toward the inside and the tooth tips of the peripheral edges are caught, and the scissors gear does not work well. Also,
Japanese Utility Model Laid-Open No. 58-177651 discloses a scissors gear in which the tooth side surface is formed into a tapered surface, but this is because the two gears that are stacked have the same thickness,
Since both edges of the tooth tips of these two gears are formed as tapered surfaces, even if the tooth tips do not get caught by each other, the strength of the tooth tips decreases and the gear transmission efficiency is poor.

[0005]

SUMMARY OF THE INVENTION Therefore, a technical object of the present invention is to obtain a scissors gear of a rotary case which is excellent in transmission efficiency of the gear without the main gear and the sub gear being scratched. The means for achieving the object is a rotary case in which a planetary gear mechanism composed of a sun gear and an intermediate gear and a planetary gear, which is used for a transmission system of a planting device of a rice transplanter, is installed, and the intermediate gear and the planetary gear are used. The gear is composed of a scissors gear that is a combination of a main gear and a sub gear, and the thickness of the main gear of this scissors gear is made thicker than the thickness of the sub gear, and the inside of the adjacent tooth tips of the main gear and the sub gear Only the peripheral edge is formed into a tapered surface, and pins with different lengths are planted on the side surfaces of the main and sub gears of the planetary gear, and springs are installed between these pins. , The pin of the main gear has a spring on the side of the sub gear that can slide in an elongated hole formed on the sub gear, and the sub gear and the spring are provided on the side opposite to the planting arm with respect to the main gear. It has such a structure.

[0006]

By forming only the inner peripheral edge of the addendum of the scissors gear on the tapered surface, the strength of the addendum does not decrease, a gap is formed between the addendums at the peripheral edge of the gear, and the addendum teeth do not contact each other. Therefore, the spacer becomes unnecessary. Without spacers, the gears will contact each other and support each other.
Gears never fall. Further, since the main gear of the scissors gear is formed thicker than the sub gear, the gear transmission efficiency is good.

[0007]

Embodiments of the present invention will be described below. First, the entire rice transplanter will be described. 11 and 12,
(1) is a passenger car body, which includes front and rear wheels (2) and (3),
Drive with the engine (4). (5) is a mission case, and (6) is a traveling transmission case. Passenger car body (1)
A planting part (8) is provided behind the plant via a lift mechanism (7). A planting arm, a fertilizer applicator (10), a seedling stand (11) and the like are attached to the planting section (8). (12) is a planting side transmission case, and the power of the engine (4) is transmitted to the transmission case (12) by a spline shaft (13). FIG. 3 shows the transmission mechanism of the planting part (8). The power transmitted to the transmission case (12) described above is applied to the endless chain (20) and the sprocket (2).
1) etc., the rotary shaft (23) is rotated via the unit clutch (22).

Sun gears (24) are loosely fitted to both ends of the rotary shaft (23), and the sun gears (24) are fixed to the transmission case (12). However, the sun gear (24) is fixed to the transmission case (12) through the sun gear phase adjusting member (25), and the relative position of the sun gear (24) with respect to the transmission case (12) is adjustable.
A hollow split rotary case (26) is mounted on the end of the rotary shaft (23) and is fixed to the rotary shaft (23) by a pin (27). An intermediate gear (28) (28) that meshes with the sun gear (24) and has the same number of teeth as the sun gear (24) is rotatably attached to the rotary case (26) by an intermediate shaft (29) (29). Has been
A planetary gear (31) having the same number of teeth, which constantly meshes with the intermediate gear (28), is attached to the planting shaft (30) via a support member (32). The intermediate gear (28) and the planetary gear (31) are so-called scissors gears in which two gears are arranged side by side, which will be described later.

These sun gear (24) and intermediate gear (2
8) and the planetary gear 31 are gears which are eccentric from the respective rotation centers by an appropriate dimension (a) as shown in FIG. A planting arm (34) is fixed to a support member (32) fitted to the planting shaft (30). (35) is a bolt for fixing the planting arm (34) to the support member (32),
(36) is a bearing interposed between the support member (32) and the planting shaft (30). A cam (37) is provided on the planting shaft (30), and a push arm (38) is in contact with the cam (37). The push arm (38) is pivotally supported by a shaft (39) and is biased by a spring (40) so as to abut the cam (37).

In FIG. 5, (41) is a planting claw, and (4)
Reference numeral 2) is a push-out claw, which is pushed out by a push rod (43) driven by a push arm (38). Now, when the rotary case (26) as a rotating body rotates about its rotary shaft (23) in the direction of arrow A as shown in FIG. 6, the sun gear (which cannot rotate with respect to the transmission case (12) ( With the rotation of the rotary case (26), the intermediate gear (28) meshing with 24) rotates in the direction of arrow B by the same angle as the rotation angle of the rotation. The support member (32) interlocking with the intermediate gear (28) via the planetary gear (31) rotates in the direction of arrow C by the rotation of the intermediate gear (28), that is, in the direction opposite to the rotation direction of the rotary case (33). Therefore, the planting arm (34) turns around the rotary shaft (21) in a state of being oriented toward the seedling placing table (11), and during this turning movement, the seedling placing table (11) is rotated. When moving the side facing to from the top to the bottom, after splitting only one seedling from the seedling mat on the seedling mounting table (11) at the tip of the planting claw (41), at the lower limit of its descending The seedlings are planted in a field scene and then rise above the field surface, and the push rods (43) push out the seedlings during planting, so that the seedlings separate from the planting claws (41).

By the way, since the sun gear (24), the intermediate gear (28) and the planetary gear (31) are all eccentric gears which are eccentric by an amount a, the rotary case (2
With the rotation of 6) in the direction of arrow A, the supporting member (3
2) revolves, and the rotation of the supporting member (32) itself in the direction C along with it revolves during rotation of the eccentric gear (2).
4) The rotation of the rotary case (26) becomes faster or slower due to the difference in the meshing pitch radius with respect to the rotating shaft in the meshing of (28), (28) and (31).

Therefore, the time when the rotation of the planting arm (34) in the direction C is delayed relative to the rotation of the rotary case (26) is approached from the seedling picking position to the upper surface of the field of the planting arm (34). By setting so as to fall respectively, and on the other hand, when rising from the planting position so as to approach the upper limit of raising of the planting arm (34),
When each planting arm (34) descends so as to approach the field scene, it is delayed in the direction C rather than the rotation of the rotary case (26) and slowly rotates freely while changing its posture downwards by the revolution, and the upper limit after planting As the rotary case (26) moves slightly faster than the rotation of the rotary case (26) in the direction C when it rises so as to approach
As shown in, the closed loop of the movement trajectory of the tip of the claw is curved by one side and the other side is a flat elliptical shape that is closer to a straight line.

In the rotary planting device as described above, in order to remove backlash caused by backlash of gears,
Both the planetary gear (31) and the intermediate gear (28) are composed of scissors gears. That is, as shown in FIG.
A planetary gear (31) is provided with two main gears (31a) and a sub gear (31b), and an intermediate gear (28) is similarly provided with a main gear (28a) and a sub gear (28b). However, only the inner surface of the peripheral portion of the tooth tip of each of the gears (31a) (31b) and (28a) (28b) has a tapered surface (31a ') (31b') (28a ') (28
b '), the contact between the tooth tips of the gear is eliminated without lowering the strength of the tooth tips of the gear. Further, since the main gears (31a) (28a) are formed thicker than the sub gears (31b) (28b), the gear transmission efficiency is good. Planetary gear (3
1) the main gear (31a) and the sub gear (31)
Two springs are stretched between b) so that one gear (31a) freely moves in the direction of rotation of the rotary case (26) and the other gear (31b) rotates the rotary case (26b). ) Is lagging behind the direction of rotation.

The main gear (31) of the planetary gear (31)
Pins (52) and (53) of different lengths are planted on the side surfaces of a) and the sub gear (31b), and springs (50) and (51) are placed between these pins (52) and (53). By being stretched, the pin (52) of the main gear (31a) can slide in the elongated hole (55) formed in the sub gear (31b). Even in a normal circular gear, a certain amount of backlash is required in terms of processing accuracy, but in a rotary device such as the present application, a backlash of a normal circular gear is not sufficient. That is, when an eccentric gear is used, the gear pitch circle is closest to the position shown in FIG. Therefore, the axes of the gears must be farther apart than those of ordinary circular gears.

Therefore, the axes are comrades, that is, the intermediate axis (2
A large backlash occurs at the C position where 9) and the planting shaft (30) are aligned. In any case, FIG. 7A
At the position, the axial distance is constant, but the axial distances are inward from each other, so the meshing is deep, and the axial distance (D1) is smaller than the axial distance (D) between the gears in the horizontal state. Therefore, the gear shift is small and the backlash is small. Since the backlash fluctuates as described above, it is necessary to forcibly eliminate the backlash in order to keep this backlash constant. Using the springs (50) (51), the main gear (31a) and the sub gear The backlash can be eliminated by sliding the gear (31b), and the spring (50) responds to the above deviation.
(51) expands and contracts, and the main gear (31a) pin (5
2) slides in the elongated hole (55) of the sub gear (31b). Even if the backlash is large, the position in FIG. 7C does not affect the seedling picking position and the planting position even if the backlash is large. Therefore, the most important seedling picking position is in FIG. 7B, which is between the minimum backlash and the maximum backlash.

The main gear (31a) and the sub gear (31
b) When the amount of co-eccentricity is constant, the shift amount changes as described above, and the position C is the maximum and the position A is the minimum, as described above. Here, the amount of deviation is the intermediate axis (29)
It is based on the line connecting the axis of the plant and the axis of the planting shaft (30), and FIG. 8 shows it. Where β1> β2. Therefore, the distance between the pins (52) and (53) is changed, and the springs (50) and (51) are also subjected to the changing load, but since the expansion and contraction of the spring is small, fatigue is small. Here, the sub gear (31
If the amount of eccentricity in b) is made smaller than that of the main gear (31a) by an amount corresponding to the change in backlash, the distance between the pins (52) and (53) becomes substantially constant, and the rotary case (26) will have a
Backlash can be removed with constant force during rotation.

The fluctuation of the backlash as described above also occurs between the intermediate gear (28) and the sun gear (24),
Since the intermediate gear (28) is composed of a scissors gear, the springs (50) (51) mounted on the planetary gear (31)
Is transmitted to each of the scissors gears of the intermediate gear (28) and the main gear (28a) and the sub gear (28b) of the intermediate gear (28) are slid, so that the backlash problem is solved in the same manner as described above. In FIG. 2, the spring tensioning method is different, and the end of the C-shaped spring (60) is bent to form an engaging portion (60 ′), which is used as the main gear (31a) and sub gear. (31b) The engaging holes (61) and (62) are engaged with each other. Here, the spring (60) is fitted in the circular groove (63) of the main gear (31a) with a margin.

[0018]

In any case, according to the present invention, a gap is formed between the tooth tips on the peripheral edge of the gear, and the tooth tips do not contact each other. Moreover, since the spacers are omitted, the gears do not fall over because the gears contact each other and support each other. Therefore, the problem that the tooth tips are caught and the scissors gear does not work well as in the conventional case is solved.
Also, since only the inner peripheral edges of the adjacent tooth tips of the main gear and the sub gear of the scissors gear are formed on the tapered surface, it is not necessary to reduce the strength of the tooth tips, and the thickness of the main gear can be set to the thickness of the sub gear. Since it is thicker than this, the gear transmission efficiency is good. Further, the rotation of the sub gear between the spring and the main gear is stabilized. In particular, with this configuration, there is no backlash in the axial direction due to the spring of the sub gear, and it is possible to prevent contact with the teeth of other main gears. In addition, the main gear can be brought closer to the planting case to stabilize the transmission and the sub gear can assist the transmission, and the side of the main gear on the opposite side of the planting case can be effectively utilized. It has the effect of being able to.

[Brief description of drawings]

1A and 1B are a front view and a side view of a scissors gear according to the present invention.

2A is a plan view of a C-shaped spring, and FIG. 2B is a vertical cross-sectional view of a scissors gear according to a modified embodiment of the present invention.

FIG. 3 is a vertical sectional view of a rotary case.

FIG. 4 is a vertical sectional view of a rotary case.

[Fig. 5] Vertical cross-sectional view of a planting arm

[Figure 6] Planted locus map

FIG. 7 is an explanatory view of rattling.

FIG. 8 is an explanatory diagram of rattling.

FIG. 9 is a vertical cross-sectional view of a rotary case according to the related art.

10 (a) and (b) are a plan view and a side view of a conventional scissors gear.

FIG. 11 is a side view and a plan view of the passenger car body towing the planting section.

FIG. 12 is a side view and a plan view of the passenger car body towing the planting section.

[Explanation of symbols]

 23 rotary shaft 24 sun gear 26 rotary case 28 intermediate gear 28a, 31a main gear 28b, 31b sub gear 28a ', 28b', 31a ', 31b' tapered surface 29 intermediate shaft 30 planted shaft 31 planetary gear 34 planted arm 50 , 51 Spring 52, 53 Pin 55 Long hole

Claims (1)

[Claims] 1. A rotary case in which a planetary gear mechanism composed of a sun gear and an intermediate gear and a planetary gear, which is used for a transmission system of a planting device of a rice transplanter, is installed, wherein the intermediate gear and the planetary gear are the main gears. The scissors gear is composed of a sub gear and a sub gear, and the thickness of the main gear of this scissors gear is made thicker than the thickness of the sub gear, and only the inner peripheral edge of the adjacent tooth tip of the main gear and the sub gear is tapered. The main gear of the planetary gear and the side of the sub-gear are planted with pins of different lengths, and springs are tensioned between these pins so that the pin of the main gear is drilled in the sub-gear. A scissors gear for a rotary case in which a spring is arranged on the side of a sub gear that can slide in an elongated hole provided, and the sub gear and the spring are provided on the side opposite to the planting arm with respect to the main gear. Ya.