JP2593072Y2 - Gear transmission - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gear transmission for a power transmission device, and is particularly suitable for use in a traveling transmission such as a combine. More specifically, the present invention relates to two shafts arranged in parallel. And a gear ratio switching structure of a three-speed transmission in which high, middle, and low three-speed transmission gears are disposed.

[0002]

2. Description of the Related Art In general, a crawler traveling device of a mobile agricultural machine such as a combine which steers the crawler by rotating the left and right crawler driving directions forward or backward is known.

With respect to such a traveling device, the present applicant has
A gear transmission as shown in FIGS. 2 and 3 has been proposed. 2 and 3, an input shaft 6 is pivotally supported by the case 5, one end of the input shaft 6 is fixed to an input pulley 7 protruding from the case 5, and the other end of the input shaft 6 is The rotation of the input shaft 6 transmitted through the input pulley 7 is connected to a hydraulic continuously variable transmission 9 mounted on the outside of the motor, and the speed of the output shaft 10 is changed by the hydraulic continuously variable transmission 9.
Is output to The hydraulic continuously variable transmission 9 is operated by a shift lever to change the speed continuously.

[0004] gear 11 is fixed to the output shaft 10 which is supported by the case 5, the driving force to the first speed-change shaft 1 is transmitted through a gear 12 which is combined bite with the gear 11. A transmission gear 13 that rotates integrally with the shaft 1 is mounted on the first transmission shaft 1 so as to be slidable in the axial direction. The transmission gear 13 is composed of gears of three different diameters for three-speed shifting, and three-speed transmission gears 15, 16,
17 to each gear and meshing of. The small gears 16 of the transmission gears 15, 16 and 17 are also meshed with a gear 19 fixed to the drive shaft 3, and transmit a driving force to the drive shaft 3.

First, a forward (forward) transmission system will be described. In addition to the gear 19, a gear 20 having a smaller diameter than the gear 19 is fixed to the drive shaft 3, and the gear 20 is fixed to the steering shaft 21. With the center gear 22 that is engaged . Inner teeth 23, 25 are formed on both left and right side surfaces of the center gear 22, and these inner teeth 23, 25 have side clutch gears 26, 25, respectively.
27 are releasably engaged. The side clutch gears 26 and 27 are rotatably and slidably attached to side clutch shafts 29 and 30 which are provided on the same axis as the steering shaft 21 and slide on the side clutch shafts 29 and 30 to the left and right. As a result, the inner teeth 2 of the center gear 22
Meshing of the 3,25 is disengaged. Output gear 33 and 35 provided on the left and right axles 31, 32 are combined bite the right and left side clutch gear 26, 27. Therefore,
The driving force of the center gear 22 is the left and right side clutch gear 2
6 and 27 are engaged with the internal teeth 23 and 25,
1, 32. The axles 31 and 32 extend in the left-right direction from the case 5, and a sprocket 36 is attached to a tip thereof, and a crawler belt 37 is wound around the sprocket 36. Thus, the side clutch gear 26,
When the clutch 27 is turned on and the friction clutches 50 and 51 described below are turned off, the drive shaft 3, the gear 20, the center gear 2
2, side clutch gears 26 and 27, output gears 33 and 3
5. The power is transmitted in the order of the axles 31, 32, and the body advances.

Next, a reverse (reverse) transmission system will be described. The left and right side clutch shafts 29, 30 reach the left and right outer sides of the case 5, and reverse rotation transmission gears 39, 40 are fixed to protruding ends, respectively. Further, inside the left and right reversing transmission gears 39 and 40, support portions 41 and 42 formed of bearings are provided.
30 and the steering shaft 21 are supported simultaneously and on the same axis.

On the other hand, a reverse rotation shaft 43 is
A free rotation gear 45 rotatably supported by the gears is meshed. A switching clutch 46 is also supported on the reverse rotation shaft 43, and the switching clutch 46 is provided so as to rotate integrally with the reverse rotation shaft 43 and to be slidable in the axial direction. The switching clutch 46 is a meshing clutch, and clutch claws are provided at both ends of the switching clutch 46.
The clutch pawl that meshes with the clutch pawl is provided inside the free rotation gear 45 and the case 5. And
The switching clutch 46 is always engaged with the clutch pawl 49 on the free rotation gear 45 side or the clutch pawl 47 on the case 5 side. When the switching clutch 46 is engaged with the clutch pawl 49 of the free rotation gear 45, the power of the drive shaft 3 is transmitted to the reverse rotation shaft 43 via the free rotation gear 45, and the switching clutch 46 When engaged, the rotation of the reverse rotation shaft 43 is restricted.

Both ends of the reverse rotation shaft 43 reach the outside of the case 5, and input ends of friction clutches 50 and 51 are attached to both ends. The friction clutches 50 and 51 are multi-plate clutches, and clutch cases 52 and 53 are formed outside the friction clutches 50 and 51. Friction clutch 50, 51
Gears 55 and 56 are formed on the output side of the
5,56 in the reverse transmission gear 39 and 40 of the above-mentioned each bite
It is case. Clutch levers 57 and 59 are provided on the outer sides of the clutch cases 52 and 53 so as to be swingable.
0 and 51 are turned on and off. The switching clutch 46 is engaged with the free rotation gear 45 side, and the side clutch gear 26,
When the clutch 27 is in the off state and the friction clutches 50 and 51 are in the on state, the drive shaft 3, the gear 19, the free rotation gear 45, the switching clutch 46, the reverse rotation shaft 43, and the friction clutches 50 and 5 are provided.
1, gears 55, 56, reverse rotation transmission gears 39, 40, side clutch shafts 29, 30, side clutch gears 26, 2
7. The power is transmitted in the order of the output gears 33 and 35 and the axles 31 and 32, and the body moves backward.

Next, a traveling operation during traveling will be described.

When the parking brake is applied, the switching clutch 46 is engaged with the clutch pawl 47 on the case 5 side to restrict the rotation of the reverse rotation shaft 43, and
0, 51 are in the ON state. Thereby, the axles 31, 32
Has braking force, and the aircraft does not move.

Next, the case of turning left is described. First, when turning left from the above-mentioned forward state, the left side clutch gear 26 is disengaged and the switching clutch 46 is engaged with the clutch pawl 47 provided on the case 5 side. The switching of the switching clutch 46 puts the reverse rotation shaft 43 in a stopped state. Here, since the right crawler 37 is driven forward, the left crawler is rotated by the forward movement of the right crawler 37, and the body gradually turns left.
When the operation amount of the operation unit is increased, the clutch lever 57 is swung, and the friction clutch 50 is turned on, the reverse rotation shaft 43
Is stopped, the left transmission system stops, and the left crawler 37 stops. This allows the aircraft to make a left pivot turn around the left crawler. When making a right turn, the switching clutch 46 is also engaged with the clutch pawl 47 on the case 5 side, and the right side clutch gear 2 is engaged.
7 is turned off and the friction clutch 51 is turned on. When the switching clutch 46 is engaged with the clutch pawl 47 on the case 5 side, since the reverse rotation shaft 43 is stopped, only pivot turning is possible.

Next, a description will be given of a case where the vehicle turns left. When turning left from the forward state, the left side clutch gear 26 is disengaged, and the switching clutch 46 is engaged with the clutch pawl 49 provided on the free rotation gear 45 side. By switching the switching clutch 46, the reverse rotation shaft 43 is always in a reverse rotation state. Here, since the right crawler 37 is driven forward, the left crawler 37 is
And the aircraft gradually turns to the left. When the operation amount of the operation unit is increased and the clutch lever 57 is swung to bring the friction clutch 50 into the half-clutch state, the sliding friction with the friction plate of the reverse rotation shaft 43 which is rotating in reverse causes the gear 55 on the output side to rotate. The forward rotation is stopped, the left transmission system stops, and the left crawler stops. When the operation amount of the operation unit is further increased to bring the friction clutch 50 into a completely engaged state, the transmission system on the left side includes the reverse rotation shaft 43, the friction clutch 50, the gear 55, the reverse rotation transmission gear 39, the side clutch gear 26, and the output gear. Reverse power is transmitted in the order of 33 and the axle 31. As a result, the left and right crawler driving directions are reversed, and the aircraft makes a super pivot turn.

The arrangement of the respective shafts is shown in FIG. 3, which is a side view showing a state where the case 5 of FIG. 2 is divided into right and left. The reverse rotation shaft 43 is connected and disconnected from the drive shaft 3 via the gear 19, the free rotation gear 45, and the switching clutch 46, and performs reverse or pivot turning.

The power at the time of forward movement is supplied from the drive shaft 3
It is transmitted to axles 31, 32 via shafts 21, 29, 30. In FIG. 2, this meaning is indicated by an arrow A from the gear 20 to the center gear 22.

[0015]

However, the vicinity of the proposed first transmission shaft 1 and second transmission shaft 2 shown in FIG. 2 is shown in FIG.
The gear 13 is attached to the shaft 1 by a spline 60 or the like so as to rotate together with the shaft 1. The gear 13 slidably mounted in the axial direction is provided with a first small gear 62 and a first small gear 62 on both sides of a first large gear 61 at the center. The middle gear 63 is integrally attached to the second transmission shaft 2.
The second large gear 17, the second small gear 16, and the second middle gear 15 meshed with these gears 62, 61, 63 are mounted so as to rotate together with the shaft 2 by a spline 65 of the shaft 2 and the like. , Spacers 66, 67, and bearings 69, 70, and are attached by the case 5 so as not to move in the axial direction.

The gears 15 and 17 are provided with bosses 15a,
It is formed eccentrically and integrally with the end of 17b. Also,
The gears 62 and 63 are also provided eccentrically at both ends with respect to the boss portion of the integrated gear 13.

Therefore, for example, when the gear 17 and the gear 62 mesh with each other and the rotational force is transmitted, the boss portion of the gear 13 and the boss portion 17 a Are inclined in directions opposite to each other, and the gear 62 and the gear 17 are engaged with each other while being inclined and contacting each other, so that the gear 62 and the gear 17 are in a single contact state. As a result, both the gears 62 and 17 are in mesh with the gears disengaged from the involute tooth form, and a vibration is generated in the transmission torque with the mutual rotation, and the vibration generates an impact between the two gears 62 and 17. Gear 6
The second tooth surface is inclined in a direction inward from the gear 17. For these reasons, the gear 62 tends to come off the gear 17. The same applies to the gears 63 and 15.

Incidentally, even when the gears 15 and 17 are integrally fixed to the shaft 2, the gears 63 and 62 are
There is a drawback that it is easy to come off because it is inclined in the direction of coming off from and meshes.

Accordingly, the present invention provides a gear transmission in which the gears at the center are selectively meshed by sliding, the left and right gears are always meshed and engaged by the dock, thereby preventing the middle gear and the left and right gears from being disengaged. The purpose is to provide.

[0020]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and, for example, as shown in FIG. 1, a second case supported in parallel to a case (5). A first speed change shaft (1) and a second speed change shaft (2); a second left gear (15) and a second middle gear (1) fixed to the second speed change shaft (2), respectively;
6) a second right gear (17), provided on the first speed change shaft (1), and the second left gear (15) and the second right gear
(17), a first left gear (76), a first right gear
Gear (77) and a first intermediate gear (16) which is disengaged from the second intermediate gear (16).
In the gear transmission having a middle gear (79) , the first middle gear (79) is configured to have a larger diameter than the first left gear (76) and the first right gear (77). 79) that rotates integrally with the first transmission shaft (1) and is slidably supported in the axial direction, and always meshes with the second left gear (15) and the second right gear (17). A first left gear (76) and a first right gear (77) are supported at both sides of the first middle gear (79) so as to be rotatable with respect to the first transmission shaft (1). The second middle gear (1) fixed to the two-speed shaft (2)
6) is configured to have a smaller diameter than the second left gear (15) and the second right gear (17) also fixed to the second speed change shaft (2) so as to be able to mesh with the first middle gear (79); First middle gear (7
9) On both sides, dogs (80, 81) having internal teeth that can directly mesh with the outer peripheral teeth of the first left gear (76) and the first right gear (77) are provided. , The first middle gear (79)
Slides in the axial direction so that the second middle gear (1
Engagement 6) and a position to mesh, in a state in which meshing is out of the second in gear (16), the first left gear (76) or the first right gear and (77) by the dog (80, 81) It is characterized in that it can be switched to a position that matches.

[0021]

With the above arrangement, when the first middle gear (79) is in mesh with the second middle gear (16), high-speed rotation is performed via these gears from the first speed-change shaft (1) to the second middle gear (79). It is transmitted to the speed change shaft (2). At this time, the first and second middle gears (79, 16) incline the gears even if there is play between the gear boss and the splines (1a), (2a) because of being located at the center. Since the force is rarely applied and the high-speed rotation is transmitted, it is not used at the time of work in a field or the like where a load is applied, and together, the middle gears (79, 16) are selectively meshed by sliding. Even if it does, the gear will not come off.

The first left gear (76) and the first right gear (77) have a second left gear (15) and a second right gear (1).
7) is always meshed with the first left gear (7).
6) and the first right gear (77) have the same gear width as the second left gear (1).
5) and the second right gear (17) is formed to be wider than the gear width so as to protrude inward in the axial direction. Then, the first middle gear (79) is slid left or right to move the second middle gear (1).
6) Unmating and dog (80 or 81)
Directly meshes with the wide gear formed on the outer peripheral surface of the first left gear (76) or the first right gear (77). For this reason, the dog (8) is provided on both side surfaces of the first middle gear (79).
0, 81) is sufficient, the first left gear (76) and the first
The right gear (77) does not need to be provided. Further, in this state, the rotation of the first transmission shaft (1) is controlled by the first middle gear (7).
9) through the first left gear (76) and the second left gear (15), or through the first right gear (77) and the second right gear (17), as a low-speed or middle-speed rotation of the second transmission shaft (2). ). At this time, the first and second left gears (76, 15) and the first and second right gears (77, 17) are always meshed with each other. The gear can be changed more easily. Furthermore, the tooth width (T) of the second middle gear (16) is made relatively wide so that there is a margin in the left-right direction with respect to the meshing of the first middle gear (79), so that it is difficult to come off. The tooth width (t) of the first middle gear (79) is relatively narrow, and the first middle gear (79) can be slid with a small sliding amount to mesh with the first left and right gears.

The reference numerals in the parentheses are mere examples, and do not limit the configuration.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG.

FIG. 1 is an enlarged view of a part of FIG. 2 described in the related art section, and the same reference numerals are given to members common to FIG.

In FIG. 1, a gear 1 is
A dog clutch 73 is provided so that the torque is transmitted to the first speed-change shaft at a high speed via the gears 1 and 12 and at a low speed via the gears 71 and 72 and the rotational force is transmitted to the first speed-change shaft. 1
A pulley 75 is fixed to a protruding portion of the transmission shaft 1 outside the case 5, and supplies two rotation speeds from the pulley 75 to the preprocessing unit. For this purpose, the running speed has been improved so that it can be selected in six steps.

Next, the main part of the present invention will be described.

The second transmission shaft 2 is provided with a spline 2a and the like.
5, so that the second small gear 16 and the second large gear 17 do not rotate with respect to the shaft 2, and these gears 15, 16 are formed by the shoulder 82 of the shaft 2 and the bearing 83 in the axial direction. It is installed so that it does not move. And the gear 15 is the boss 15
Outside of a, the gear 17 is eccentric to the outside of the boss 17a.

The first transmission shaft 1 has a second middle gear 15
The first middle gear 76 that meshes with the needle bearing 76a
The first small gear 77 meshing with the second large gear 17 is rotatably mounted on the needle bearing 7.
7a rotatably attached. Further, the gear widths formed on the outer peripheral surfaces of the first middle gear 76 and the first small gear 77 described above project axially inward from the gear widths of the second middle gear 15 and the second large gear 17. It is set wide.

A first large gear 79 meshed with a spline 1a provided at an intermediate portion between the gears 76 and 77 of the first transmission shaft 1 is mounted on the shaft 1 so as to be movable in the axial direction. 79 is adapted to mesh with the second small gear 16.

On the gear 76 side of the first large gear 79, there are provided internal teeth 80 that directly mesh with the gear 76 protruding inward in the axial direction, and on the gear 77 side of the first large gear 79. The gear 7 similarly protrudes inward in the axial direction.
7 is provided with internal teeth 81 that directly mesh with the internal teeth 7.

Thus, when the first large gear 79 is in the position shown (substantially at the center of the spline 1a), the second small gear 1
6, the first speed change shaft 1 to the second speed change shaft 2
High-speed rotation is transmitted to the internal gear 80 of the first large gear 79
When meshing with the middle gear 76, the spline 1
a, the medium speed rotation is transmitted to the shaft 2 via the gear 79, the internal teeth 80, the gear 76, and the gear 15, and similarly, the internal teeth 81 of the gear 79
Is engaged with the first small gear 77 when the shaft 1
Low-speed rotation is transmitted to.

In the above, the internal teeth 80 of the first large gear 79
There when engaged in first left gear 76, via the inner teeth 80 of the entire circumference from the gear 79 from the shaft 1 via a spline 1a, the rotational force is transmitted to the entire circumference manner to the first left gear 76 Therefore, the reaction force acts on the gear 79 as a complete rotational force, so that even if there is play between the gear 79 and the spline 1a, no external force for inclining the gear 79 works. As a result, the internal teeth 80 accurately hit the gear 76, and the gear 79 can be prevented from coming off the gear 76. Internal gear 81 is gear 7
7 is exactly the same.

Further, in this embodiment, the dog is set to the internal teeth 80 and 8.
1 and the gears 76 and 77, for example, the internal teeth 8
If the teeth of 0,81 are skipped one by one, the gears 76,7
Since the chance (probability) of meshing with the gear 7 is increased, the gears can be meshed more easily than the gears. Even in the case of a general dog clutch, the gears can be meshed more easily than the gears for the above-described reason.

Further, since the dog meshing method requires less gear sliding than the gear meshing method, the gear device can be made compact.

Next, another embodiment will be described.

[0037] In FIG 1, with respect to the gear unit in <br/> core wire of the first large gear 79, center the gear width of the gear 79.
That is, d1 = d2 .

The center of the boss 16a is aligned with the gear center line of the second small gear 16. That is, L1 = L2.

In this way, when the first large gear 79 and the second small gear 16 mesh with each other to transmit a rotational force, the reaction force is exerted on the splines 1a and 2a of the shafts 1 and 2, but the spline Gear 7 even if there is play in 1a, 2a
Since the gear surfaces 9 and 16 do not lean and the gear surfaces exactly hit each other,
The gear 79 can be prevented from being disengaged from the gear 16 during high-speed gear shifting.

Next, another embodiment will be described.

In FIG. 1, the width of the second small gear is T,
Assuming that the width of the large gear 79 is t, the large gear 79 is formed such that T> t.

By doing so, the sliding width of the first large gear 79 can be reduced, the gear device can be made compact, and the shifting force of the gear 79 can be reduced (the gear 79
The gear width t can be reduced due to a small reaction force.)

Further, by increasing the width T of the second small gear 16, it is possible to provide a margin when the gear 79 is disengaged from the gear 16, and to increase the durability of the second small gear 16.

Although the gears 15, 16, 17 are fitted into the shaft 2 by splines 2a or the like, they may be press-fitted into the shaft 2 or may be formed integrally.

[0045]

As described above, conventionally, the first middle gear
So that it shifts on the first transmission shaft
The first left and right gears separated from the first middle gear
The first left and right gears are loosely fitted to the shaft, and the first left and right gears are fixed to the second transmission shaft.
2Always mesh with left and right gears, high speed and low load
Only the first middle gear is shifted
Disengage and engage the first middle gear with the first left gear.
Or directly mesh with the outer peripheral teeth of the first right gear.
By doing so, the fall of each gear and the resulting gear
Prevents disengagement and transmits highly reliable 3-speed shifting power
I can. That is, the first middle gear is made independent,
Since the gears can be engaged without being eccentric, the disengagement of both gears can be prevented, and
The transmission of power where a large work load acts is performed by the first left and right gears.
And the second left and right gears that always mesh with this
And the second left and right gears are fixed to a second speed change shaft.
Therefore, the outside of the gear due to the fall of the first and second left and right gears
This can be prevented. Also, by gear slide
Shift change only the first middle gear for high speed transmission with little load
By doing so, the probability of occurrence of gear disengagement can be significantly reduced. The first right and left gear is high torque caused by the load than the first during gear acts, dog provided during the first gear fitted Shiteko the outer peripheral teeth portion of the first lateral gear
To directly meshing driven les, first in gear, the first right and left gear
Are prevented from falling down and are out of mesh with the second left and right gears.
This can be reliably prevented, and good power transmission without vibration or the like can be performed.

[Brief description of the drawings]

FIG. 1 is a sectional front view of a gear transmission showing an embodiment of the present invention.

FIG. 2 is a cross-sectional development view showing a crawler traveling power transmission device already proposed by the present applicant.

FIG. 3 is a front view showing the case in half.

FIG. 4 is an enlarged longitudinal sectional side view showing the transmission unit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st speed change shaft 2 2nd speed change shaft 5 Case 15 2nd left gear (2nd middle gear) 16 2nd middle gear (2nd small gear) 17 2nd right gear (2nd large gear) 76 1st left gear (1st middle gear) 77 1st middle gear (1st small gear) 79 1st middle gear (1st large gear) 76, 77 dog (inner end of gears 76, 77) 80, 81 dog (internal teeth)

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-176238 (JP, A) JP-A-60-155505 (JP, A) JP-A 63-45443 (JP, U) JP-A 63-45443 185947 (JP, U) Japanese Utility Model Showa 58-35041 (JP, U) Japanese Utility Model Showa 60-12726 (JP, U) Japanese Utility Model Showa 51-36135 (JP, Y2) Japanese Utility Model Showa 51-5656 (JP, Y2) (58) Field surveyed (Int. Cl. ⁶ , DB name) F16H 3/00-3/42

Claims (1)

(57) [Scope of request for utility model registration] 1. A first speed change shaft and a second speed change shaft supported in parallel to a case, and a second left gear, a second middle gear, and a second right gear fixed to the second speed change shaft, respectively. , Which is provided on the first transmission shaft and constantly meshes with the second left gear and the second right gear.
Meshes with the first left gear, first right gear and second middle gear
A gear transmission having a first middle gear to be disengaged , wherein the first middle gear has a larger diameter than a first left gear and a first right gear, and the first middle gear is integrally formed with the first transmission shaft. A first left gear and a first right gear that rotate and are slidably supported in the axial direction, and always mesh with the second left gear and the second right gear, are provided on both sides of the first middle gear. wherein while rotatably supporting the first gear shaft, a second intermediate gear fixed to the second speed-change shaft, also the second variant Te
The second left gear and the second right gear fixed to the speed shaft are configured to have a smaller diameter than the second right gear and can be meshed with the first middle gear. The first left gear and the first right gear are provided on both side surfaces of the first middle gear. A dog capable of directly meshing with the outer peripheral teeth of the first middle gear is disengaged from a position meshing with the second middle gear by sliding in the axial direction with the second middle gear. The gear transmission is adapted to be switched to a position where the first left gear or the first right gear engages with a dog in a state where the gear is engaged.