KR101868504B1 - Device for transmitting control force of HST for work vehicle - Google Patents

Abstract

[0001] The present invention relates to a HST driving force transmitting device for a work vehicle, and more particularly, to a trunnion arm for inputting an operating force according to the operation of a turning operation mechanism to a turning HST, And a swing servo mechanism for transferring the swing arm to the inside; Wherein the servo mechanism for pivoting is configured such that either one of the differential pressure between the neutral position of the trunnion arm and the differential pressure for the left (?) Swing operation and the right (?) Swing operation is greater than the other differential pressure By setting it higher, it is possible to improve the straightness of the vehicle.

Description

[0001] The present invention relates to a HST driving force transmitting device for a vehicle,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving force transmitting device for a working vehicle, which is provided in a working vehicle for agricultural machinery such as a combine, a tractor, and the like, and transmits the driving or turning driving force of the driver to the continuously-

Generally, the working vehicle for agricultural machinery includes tractor, combine, and rice milling machine. Among them, the combine is a working car for agricultural machinery that breaks, selects and harvests rice, barley, wheat, etc., and adopts a crawler type driving system because of its working characteristics.

The combine has a power transmission structure for shifting the power generated by the engine as a driving source in the transmission and transmitting the shifted power to a driving wheel for traveling.

Particularly, the transmission is equipped with a hydraulic type continuously variable transmission (HST) (hereinafter, also referred to as 'HST') which allows a continuously variable transmission. In the case of a crawler type combine, a traveling HST and a turning HST .

The forward and reverse continuously-variable shifting through the driving HST is enabled by operating the levers in the vicinity of the driver's seat. When the levers in the periphery are operated, they are transmitted to the traveling HST via the traveling operation transmitting device composed of a link mechanism to transmit the operating force of the levers in the vicinity, and the power input from the engine is shifted from the traveling HST to the desired speed range And then transmitted to the drive shaft through the transmission mechanism, the planetary gear mechanism, the transmission gear mechanism, and the like, thereby driving the crawler on the right and left sides of the traveling body.

The continuously-variable shifting through the HST for turning can be performed by operating the turning lever provided on the driver's seat while the vehicle is advancing or retracting. When the revolving lever is operated, the revolving operation is transmitted to the revolving HST through a swing operation transmitting device including a rod and a link for transmitting the operating force of the revolving lever, and the output power is transmitted to the turn gear through the idle gear of the transmission The input is reversed. When the turn gear is reversed, the output of one side is decelerated more than that of the straight ahead, and the output of the opposite side is increased more than that of the straight ahead, so that a difference in rotation is generated between the left and right crawlers, and as a result, the vehicle can be turned.

As a result, the running HST is operated by the forward, neutral, and reverse operations of the peripheral speed lever, and the turning HST is operated by the left turn, neutral, and priority operation of the turning lever. At this time, the peripheral speed lever transmits the operating force to the traveling HST through the traveling operation transmitting device connected to the traveling HST, and the turning lever transmits the operating force to the turning HST through the swing operation transmitting device connected to the traveling HST.

However, since the driving force transmitting device for transmitting the operating force to the respective HSTs from the peripheral speed lever or the revolving lever is composed of the integral link structure, the peripheral speed lever or the turning lever may move finely regardless of the driver's will, There is a problem that the operation force transmission device operates sensitively and malfunction occurs.

That is, since the operation force transmitting device is connected by a link mechanism such as an arm and a rod, and each connecting portion is integrally coupled with the hole and the pin and is configured to simultaneously transmit the operating force while being integrally moved by lever operation or the like, Even when the lever is moved finely regardless of the driver's will in the neutral state of the lever, the operating force transmitting device is interlocked and the operating force is transmitted to the HST. When the misfeeded operating force is transmitted to the HST, Problems such as the vehicle turning back and forth or turning are generated. As a result, the reliability of the operation force transmitting device is deteriorated and a safety accident may occur.

Korean Patent No. 10-0584785 Korean Patent No. 10-1301859

SUMMARY OF THE INVENTION The present invention has been conceived to solve the problems described above, and it is an object of the present invention to provide an HST driving operation force of a work vehicle which can improve the straightness of a vehicle and increase the reliability of driving operation, And to provide a delivery device.

The HST driving force transmitting device for a work vehicle according to the present invention for realizing the above object includes a trunnion arm for inputting operation force according to the operation of the turning operation mechanism to the HST for turning, To the inside of the HST using a hydraulic pressure; Wherein the servo mechanism for pivoting is configured such that either one of the differential pressure between the neutral position of the trunnion arm and the differential pressure for the left (?) Swing operation and the right (?) Swing operation is greater than the other differential pressure Is set higher.

Here, the?,? Direction differential pressure of the servo servomotor for swing is lower than the? Differential pressure of the? Servo pressure of the swing servomotor at the time of swinging in the left (?) Direction, At the time of swing, the pressure difference at the β side can be set to the unilateral pressure higher than the differential pressure.

On the other hand, the?,? Direction differential pressure of the servo mechanism for swiveling is lower than the differential pressure of? On the? -Position of the swivel servo mechanism when the swiveling servo mechanism is rotated in the right (?) Direction, , The pressure on the? Side may be set to a unilateral pressure higher than the primary pressure.

The differential pressure difference between the α and β directions of the servo mechanism for pivoting is set to be lower by about 3 to 7 bar than the β differential pressure when the swinging motion is in the left direction α direction, The pressure on the β side of the servo mechanism can be set 5 to 7 bar higher than the differential pressure.

On the other hand, a traveling trainer arm for inputting operation force according to the operation of the peripheral speed lever to the traveling HST, and a traveling servo for transmitting the operating force inputted through the traveling traynion arm to the inside of the traveling HST A mechanism is provided; It is preferable that the driving servomechanism is set so that the difference between the advance (a) and reverse (?) Difference pressures is set to be the same around the neutral position of the throne arm.

At this time, the differential pressure of? And? Of the traveling servomechanism can be set to? 5 bar at the basic pressure of charge.

The above and other objects and advantages of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which: In addition to the principal task solutions as described above, various task solutions according to the present invention will be further illustrated and described.

The HST driving force transmitting device for a work vehicle according to the present invention can improve the straightness of the vehicle because the chock pressure of the swing servomechanism is set to be the unilateral pressure and the chock pressure of the traveling servomechanism is set to be the same When the vehicle is stopped, the neutral maintenance performance can be improved.

FIG. 1 is a perspective view showing a traveling and turning operation force transmitting device and a speed changing device according to an embodiment of the present invention.
Fig. 2 is a perspective view of a main portion of the driving force transmitting device for driving and turning driving shown in Fig. 1. Fig.
FIG. 3 is a configuration diagram showing a traveling driving force transmitting device according to an embodiment of the present invention.
4 is a configuration diagram illustrating a turning driving force transmitting device according to an embodiment of the present invention.
5 is a view for explaining a buffer hole of the driving force transmitting device for traveling and turning driving according to an embodiment of the present invention.
6 to 9 are graphs showing vehicle movement according to an extended length of a buffer hole of a running driving force transmitting device according to an embodiment of the present invention.
10 to 13 are graphs showing vehicle movement according to an extended length of a buffer hole of a turning driving force transmitting device according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

1 is a perspective view showing a driving force transmitting device and a shift device of a working vehicle according to an embodiment of the present invention.

In Fig. 1, reference numeral 100 denotes a speed change device, and 150 denotes a drive output shaft. Reference numeral 201 denotes a peripheral lever, and reference numeral 301 denotes a pivot lever.

The transmission 100 is provided with various transmission mechanism devices for advancing and retracting the vehicle, accelerating / decelerating, and turning left and right. In addition, the traveling HST 210 for forward and reverse continuously variable shifting and the left- The HST 310 for turning is provided.

The transmission 100, the traveling HST 210, and the HST 310 for pivoting are well-known structures and can be implemented using such a known configuration, so that the exemplary embodiments of the present invention will not be described in detail. And the shifting operation transmitting device which is a main constituent of the present invention will be mainly described.

A traveling operation transmitting device 200 is connected between the peripheral speed lever 201 and the traveling HST 210 to transmit a shifting operation force of the peripheral speed lever 201. The swing lever 301 and the HST And a turning operation transmitting device 300 is connected between the turning lever 301 and the turning lever 310 to transmit the turning operation force of the turning lever 301.

The traveling operation transmitting device 200 and the swing operation transmitting device 300 will be described as follows.

First, the configuration of the traveling operation transmitting device 200 for the peripheral speed lever 201 will be described.

1, a running potentiometer 220 is provided below a peripheral lever 201 to sense an operation state of the peripheral speed lever 201 through the driving potentiometer 220 Or < / RTI >

The driving potentiometer 220 is capable of transmitting a signal to a driving control unit (not shown) for controlling the driving operation motor 230. The driving operation motor 230 is operated in accordance with the signal of the driving control unit And controls the traveling HST (210) by moving the traveling operation transmitting device (200). Here, the travel control unit may be configured to be combined with the driving potentiometer 220 or the traveling operation motor 230, or it may be configured separately.

The traveling operation transmitting device 200 can be designed in various ways according to the distance between the traveling operation motor 230 and the traveling HST 210, the relationship with the surrounding structures in the gas, and the like.

The traveling operation transmitting device 200 illustrated in FIG. 1 exemplifies a link connecting structure using a plurality of arms and rods between a traveling operation motor 230 and a traveling HST 210, The first transmission rod 240, the arm unit 250, the second transmission rod 260, the trunnion arm 270 for driving, and the like in the order of transmission of the operation force from the transmission arm 230 do.

The traveling operation transmitting device 200 transmits the operating force while moving or rotating together with the movement of the traveling motor arm 235 rotated by the traveling operation motor 230 to thereby drive the traveling HST 210 connected to the traveling HST 210 And is configured to transmit the operation force of the peripheral speed lever 201 to the traveling HST 210 by rotating the trunnion arm 270 at a predetermined angle in the left and right direction at a neutral position.

Here, each of the arms, rods, and the like that constitute the traveling operation transmitting device 200 are connected by a link structure. Hole H is formed so that the mutual connecting portion can rotate relative to each other, P) are combined with each other.

Particularly, in the traveling operation transmitting device 200, the traveling buffer connecting part 280 is configured to prevent malfunction of the peripheral speed lever at any part of the plurality of parts where the pin P and the hole H are coupled to each other The traveling buffer connection unit 280 includes a traveling buffer hole 281 formed in a long hole structure and a traveling buffer pin 285 connected to the traveling buffer hole 281.

The driving buffer holes 281 are formed in a circular shape so as to match the outer diameter of the pin P except for the driving buffer hole 281. However, ) Or in a direction in which a force is transmitted by the buffer pin 285 for driving. Here, the drive buffer pin 285 can be configured to have the same specifications as the other pins P. [

2 and 3, a traveling buffer hole 281 having a long hole structure is formed at the lower end of the second transmission rod 260, and a driving trunnion arm 281 270 is inserted into the buffer pin 285 for driving.

For reference, the sizes of the holes are overrepresented so that the driving buffer holes 281 are clearly represented in Figs. 2 to 3.

In FIG. 2, since the second transmission rod 260 moves in the vertical direction, the traveling buffer hole 281 formed here also moves in the vertical direction. Therefore, the traveling buffer hole 281 is formed to be long in the vertical direction so as to transmit the traveling operation while having a buffer section with the traveling buffer pin 285.

The length of the running buffer hole 281, that is, the extended length, will be described in detail below with reference to equations and graphs.

On the other hand, since the traveling buffer pin 285 moves in the arc section while finely rotating at a constant angle in accordance with the rotational locus of the trunnion arm 270 for driving, the traveling buffer hole 281 is fine, It is preferable to form it long.

It is also possible to provide a buffer member for holding the position of the drive buffer pin 285 in the drive buffer hole 281. [ The buffer member is a member that provides a certain degree of elasticity at both sides of the drive buffer pin 285 so that the pin is in the neutral position of the drive buffer hole 281 and can be constituted by a normal coil spring member or the like . The buffer member may be fixed to both sides of the buffer pin 285 for running, or may be fixedly provided in the buffer hole 281 for driving.

However, since the buffer member has a low elastic force such that the elastic force does not affect the force transmitted when the elastic force is transmitted, and the buffer pin for traveling 285 moves in the middle of the buffer hole for travel 281 So that the elastic force can be provided.

When the buffer member is formed in the traveling buffer hole 281 as described above, it is preferable that the extended length of the buffer hole 281 is made as large as possible in consideration of the space occupied by the buffer member.

On the other hand, the second transmission rod 260 is provided with a turnbuckle 265 for driving to change the length for proper neutral position as the running buffer hole 281 of the long hole structure is formed . The turnbuckle has a well-known structure. One male screw is a right screw and the other male screw is a left screw. When the nut fastened to both male screws is rotated, the two male screws approach each other and the rotation is reversed.

The traveling buffer connection unit 280 is provided at the connection portion between the second transmission rod 260 and the trunnion arm 270 for driving. However, since the arm unit 250 and the second It is also possible to constitute the connecting portion of the transmission rod 260. 1, the traveling buffer connection unit according to the present invention includes a connecting portion of the traveling motor arm 235 and the first transmission rod 240 or a connecting portion of the first transmission rod 240 and the arm unit 250 It is also possible to construct a connection part or the like.

However, when the traveling buffer connecting portion 280 is provided at the connecting portion between the second transmitting rod 260 and the trunnion arm 270 for traveling, as shown in the drawing, the traveling buffer connecting portion 280 is connected to the traveling trunnion arm 270, The minute load that can be transmitted to the knee arm 270 is blocked or absorbed, so that the reliability of the traveling operation transmission can be enhanced.

It is preferable that the erroneous operation preventing structure of the peripheral lever 201 using the traveling buffer unit 280 is configured in only one of the engagement portions of the plurality of pins and the holes in the entire traveling operation transmitting device 200, But it is also possible to constitute at least two portions depending on the operating conditions.

In this embodiment, the traveling operation motor 230 is operated by a signal that senses the operating state of the peripheral speed lever 201, and the traveling operation transmitting device 200 is operated by the traveling operation motor 230 The present invention is not limited to this embodiment and the operation force of the peripheral speed lever 201 may be mechanically changed without using the driving potentiometer 220 and the traveling operation motor 230. However, It is also possible to apply the present invention to a system configured to directly transmit to the traveling operation transmitting device 200.

Now, a method of setting an appropriate extension length of the driving buffer hole 281 will be described.

Referring to FIG. 3 and FIG. 5, the design formula of the running buffer hole 281 is as follows.

Referring to FIG. 5, since the buffer hole is elongated like an oval shape in the operation force transmitting direction, the extended length C _{d of the} buffer hole and the relational expression of the short axis a and the long axis b are expressed by Equation 1 .

[Equation 1]

C _d = b - a

3, the length of the input arm 255 of the arm unit 250 is L _d1 , the length of the trunnion arm 270 is L _d2 , and the length of the trunnion arm 270 of the vehicle When the left and right operating angles are? And?, The extended length C _d of the traveling buffer hole 281 is expressed by Equation (2).

&Quot; (2) "

C _d = k · L _{d 1} /

Here, k represents a constant for setting the driving buffer hole 281. The constant k can be appropriately changed according to the design conditions such as the operation force transmission mechanism or the transmission mechanism, but is set to 1.08 in the present embodiment.

The actuating angles? And? Of the trunnion arm 270 are set to the same value, and the operating angle of the trunnion arm of the traveling HST is normally set to 18 degrees. Therefore, L _d2 is set to 18 do.

The extended length C _d of the buffer hole 281 is set to be smaller than the extended length C _d of the arm unit 250 in a state where the L _d2 value is fixed, since C _d = 1.08L _d1 / 18 in Equation (2) And the length L _d1 of the input arm 255 of the input arm 255. That is, when the length (L _d1) of the input arm becomes large, becomes even much larger buffer hole expansion length (C _d), when the length (L _d1) of the input arm becomes small, and the buffer hole expansion length (C _d) And so on.

The reason why the extension length C _d is designed to be large as the length L _d1 of the input arm increases is because the length of the input arm is set to be longer than the length of the input arm The angle gradually becomes smaller, and accordingly, the transmission of the operation force of the lever in the vicinity is sensitized at a small angle. Therefore, it is desirable to increase the extension length C _d of the buffer hole 281 as the length of the input arm increases, thereby extending the buffer section.

Table 1 below shows the extension length (C _d ) which is set according to the change of the length (L _d1 ) of the input arm.

Length of input arm (L _d1 ) Trunnion arm length (L _d2 ) Buffer hole extension length (C _d ) 18 60 1.08 24 60 1.44 30 60 1.80 36 60 2.16 42 60 2.52 48 60 2.88 50 60 3.00 54 60 3.24 60 60 3.60 66 60 3.96 72 60 4.32 78 60 4.68 84 60 5.04 90 60 5.40

When the extended length (C _d) of the input arm length (L _d1) can be appropriately set the extension length (C _d) in accordance with the change, but the running buffer hole 281 for, as in Table 1 is too low, Even when the driver does not operate the lever in the neutral state as in the case where there is no buffer hole, there is a possibility that the lever may react sensitively due to external factors and malfunction due to external factors, There is a problem that is not easy. On the other hand, if the extended length C _d of the buffer hole 281 for driving is too large, there is a problem that the car feels jolted due to the vehicle sudden start or the like at the starting point of travel and the ride feeling may be lowered.

The length L _d1 of the input arm 255 of the arm unit 250 is preferably equal to or smaller than the length L _d2 of the trunnion arm 270 for driving in consideration of the operation force transmission angle and the like. That is, the length (L _d1 ) of the input arm (255) is L _d2 / 2 to L _d2 Degree. At this time, the extended length C _d of the running buffer hole 281 is preferably 1.80 mm to 3.60 mm, more preferably, the length L _d1 of the input arm 255 is The extended length C _d of the running buffer hole 281 may be set to about 2 to 4 mm around 3 mm.

This will be described with reference to Figs. 6 to 9. Fig.

Figs. 6 to 9 are graphs showing vehicle movement along the length of the driving buffer hole 281. Fig.

As shown in FIG. 6, when the extended length C _d of the running buffer hole 281 is 0, there is no neutral section, so it is difficult to operate the levers in the vicinity and the driver unexpectedly moves the vehicle forward or backward Can occur.

However, as shown in FIG. 7, when the running buffer hole 281 having the extended length of 2 mm is formed, the neutral buffer section is formed by the extended portion, so adjustment is easy, and the vehicle is kept neutral and stable Work becomes possible.

8 and 9 are graphs showing vehicle movement when the extension length of the driving buffer hole 281 is 3 mm or more.

As shown in FIG. 8, even when the extension length of the running buffer hole 281 is 3 mm, it is easy to adjust because there is a neutral section, and the vehicle can be kept in neutral during the operation and stable operation is possible.

However, as shown in Fig. 9, when the extended length of the running buffer hole 281 is 5 mm or more, adjustment is easy because there is a neutral section, the vehicle movement becomes dull at the initial operation of the peripheral speed lever, There is a problem in that a sudden start-up phenomenon may occur when the inclination is large.

Therefore, the extension length C of the running buffer hole 281 can be set to 0.5 to 6 mm, but is preferably set to about 2 to 4 mm.

Next, the configuration of the swing lever 301 side swing operation transmitting device 300 will be described.

1, a turn potentiometer 320 is provided on a lower portion of a swing lever 301 constituting a swing operation mechanism like the peripheral speed lever 201, and the turn potentiometer 320 So that the operating state of the turning lever 301 can be detected.

The turning potentiometer 320 is capable of transmitting a signal to the swing control unit (not shown) for controlling the swing operation motor 330. The swing operation motor 330 is operated in accordance with the signal of the swing control unit And controls the turning HST 310 by moving the turning operation transmitting device 300. In other words, the turning operation motor 330 rotates and drives the turning motor arm 335, which will be described later, by the turning control unit, so that the turning of the vehicle can be controlled by the turning angle, such as the fine turning, the break turn, .

On the other hand, the turning control unit may be provided together with the turning potentiometer 320 or the turning operation motor 330, or may be separately configured.

The turning operation transmitting device 300 can be designed in various ways according to the distance between the turning operation motor 330 and the turning HST 310, the relationship with the surrounding structure, and the like.

The swing operation transmitting device 300 illustrated in FIG. 1 is configured by connecting between a swing operation motor 330 and a swing HST 310 using an arm and a rod in a link structure, A turning motor arm 335, a pivoting transmission rod 360, a pivoting trunnion arm 370, and the like in the order of transmission of the operating force from the pivoting arm 330.

The swing operation transmitting device 300 transmits the operating force while moving or rotating together with the movement of the swing motor arm 335 rotated by the swing operation motor 330, The trunnion arm 370 is rotated at a predetermined angle to transmit the operating force of the swing lever 301 to the HST 310 for turning.

Each of the arms, rods, and the like that constitute the swing operation transmitting device 300 has a structure in which a hole H is formed at the interconnecting portion and the pin P is coupled to the arm, .

In particular, at least one of the parts where the pin and the hole are coupled in the swing operation transmitting device 300 is constituted by a swing buffer connection part 380. The swinging buffer connection part 380 includes a swinging buffer Hole 381 and a swinging buffer pin 385 which is inserted and connected to the swinging buffer hole 381.

The other holes except for the turning buffer hole 381 are formed in a circular structure corresponding to the outer diameters of the respective pins. However, the turning buffer hole 381 is provided with a swinging buffer pin 385 ) Or in a direction in which the force is transmitted by the pivoting buffer pin (385). On the other hand, the swinging buffer pin 385 can be formed to have the same standard as the other pins P. [

2 and 4, the hole formed at the end of the swinging transfer rod 360 is formed as a swinging buffer hole 381 having a long hole structure, and a swinging protrusion 370 protruding from the swinging trunnion arm 370 So that the operating force is received when the buffer pin 385 is inserted into the swing buffer hole 381.

In FIG. 4, too, the hole size is excessively expressed so that the turning buffer hole 381 is clearly expressed.

2, since the swing transferring rod 360 moves in the vertical direction according to the driving of the motor, the swinging buffer hole 381 formed here also transmits the swinging operation force with the buffer section to the swinging buffer pin 385 .

The length of the elongated hole of the swinging buffer hole 381, that is, the extended length will be described in detail below with reference to equations and graphs.

On the other hand, since the pivoting buffer pin 385 moves in the arc section while finely rotating at a constant angle in accordance with the rotation locus of the pivoting trunnion arm 370, the pivoting buffer hole 381 is also fine It is preferable to form it long.

It is also possible to provide a buffer member for holding the position of the swinging buffer pin 385 in the swinging buffer hole 381 in the same manner as the traveling buffer unit 280.

On the other hand, the turning transferring rod 360 is provided with a turnbuckle 365 for changing the length for proper neutral position setting as the swinging buffer hole 381 having the long hole structure is formed .

The swing buffer unit 380 may be configured such that the swing buffer hole 381 and the swing buffer pin 385 are formed at the connection portion between the swing transfer rod 360 and the swing trunnion arm 370 It is also possible to constitute the connecting portion between the swing motor arm 335 and the swinging transfer rod 360. [ Here, when the swing buffer connection portion 380 is provided at the connection portion between the swing transferring rod 360 and the swing trunnion arm 370, the swing buffer connection portion 380 is connected to the swing trunnion arm 370 A minute load or the like that can be transmitted is blocked or absorbed, so that the reliability of the turning operation transmission can be enhanced.

It is preferable that the erroneous operation preventing structure of the turning lever 301 using the pivoting buffer hole 381 having the long hole structure is formed only in one portion of the engagement portion of the plurality of pins and the holes in the entire swing operation transmitting device 300 However, it is also possible to constitute at least two portions depending on the operating conditions.

In the above description, the structure for generating the turning operation force by using the turning lever 301 as the turning operation mechanism has been described. However, the present invention is not limited to this, and the turning operation force can be generated by using the handle. That is, the turning handle is used as the turning operation mechanism, instead of the turning lever.

The structure using the handle is generally constituted by a rim of a circular structure operated by a driver and a spoke for supporting the rim, and a handle shaft for transmitting the rotational force of the rim at the center of the rim. It is preferable that the turning operation motor is driven by detecting the degree of rotation of the handle shaft by using the turning potentiometer 320 or the like as described above also in the structure using the turning handle. Such a handle using turning operation structure is disclosed in Japanese Patent Laid-Open Nos. 10-1370993 and 10-2011-0068733, so that detailed drawing examples and explanations thereof will be omitted.

Now, a method of setting an appropriate length of the swinging buffer hole 381 will be described.

Referring to FIGS. 4 and 5, the design equation of the swinging buffer hole 281 is as follows.

Referring to FIG. 5, the extended length (C _t ) of the buffer hole and the relational expression (a) and (b) of the short axis (a)

&Quot; (3) "

C _t = b - a

4, the length of the swing motor arm 335 is L _t1 , the length of the swing trunnion arm 370 is L _t2 , the left and right operating angles of the swing trunnion arm 370 are α, ?, the extended length C _t of the buffer hole is expressed by Equation (4).

&Quot; (4) "

C _t = k · L _{t 1} / α

Here, k represents a setting constant of the swing buffer hole. The constant k can be appropriately changed according to the design conditions, and is set to 1.2 in the present embodiment.

And, L _t2 is because the operation angle α and β have the same value of the trunnion arms (370) for, turning to 60mm fixed value, the operating angle of the trunnion arms of the turning HST for the setting to the normal 18 ° is set to 18 do.

When this setting as, [Equation 4] C _t = 1.2L _t1 / 18 is therefore, in a state where the L value _t2 is fixed, the length of the arm swing motor (335) for, depending on the size of the hole extended length L _t1 buffer (C _t ) is also different. That is, when the length L _t1 of the motor arm becomes large, the extended length C _{t of the} buffer hole becomes large. When the length L _t1 of the motor arm becomes small, the extended length C _{t of the} buffer hole It will be that much smaller.

The reason for designing the extended length C _t of the buffer hole as the length L _t1 of the motor arm becomes larger is that the turning trunnion arm 20 is set at 18 degrees as the length L _t1 of the motor arm becomes longer, The angle for actuating the lever 370 is gradually reduced, and thus the transmission of the operating force of the turning lever is made sensitive at a small angle. Therefore, it is preferable to increase the extension length C _t of the buffer hole 381 as the length L _t1 of the motor arm increases, thereby extending the buffer section.

Table 2 shows the extension length (C _t ) of the buffer holes set in accordance with the change in the length (L _t1 ) of the motor arm.

The length (L _t1 ) Trunnion arm length (L _t2 ) Buffer hole extension length (C _t ) 18 60 1.20 24 60 1.60 30 60 2.00 36 60 2.40 42 60 2.80 48 60 3.20 50 60 3.33 54 60 3.60 60 60 4.00 66 60 4.40 72 60 4.80 78 60 5.20 84 60 5.60 90 60 6.00

If the extended length C _t of the turning buffer hole 381 is too small as the extended length of the driving buffer hole 281, even if the driver does not operate the lever in the turning lever neutral state There is a possibility that a malfunction may occur due to an external factor or the like, and it is also difficult to adjust the position from the left-handed turn or the priority turning operation to the neutral state. On the other hand, if the extension length C _t of the swinging buffer hole 381 is too large, a vehicle sudden turning phenomenon may occur at the turning start point.

The length L _t1 of the swinging motor arm 335 is preferably smaller than or equal to the length L _t2 of the swing trunnion arm 370 in consideration of the operation force transmission angle and the like. That is, the length L _t1 of the motor arm 335 is 0.3L _t2 to L _t2 Degree. The extended length C _t of the swinging buffer hole 381 is preferably 1.20 mm to 4.0 mm with reference to Table 1 and more preferably the length L _t1 of the swing motor arm 335 The extension length C _t of the swinging buffer hole 381 may be set to about 1.5 mm to about 3 mm around 2 mm.

This will be described with reference to FIGS. 10 to 13. FIG.

Figs. 10 to 11 are graphs showing the vehicle movement along the length of the swing buffer hole. Fig.

10, when the extended length C _t of the swinging buffer hole 381 is 0, there is no neutral section, so that it is difficult to operate the swing lever, and the vehicle is left unattended or prioritized Malfunction may occur.

However, as shown in FIG. 11, when the swinging buffer hole 381 having the extension length C _t of 2 mm is formed, the neutral buffer section is formed by the extended portion, so adjustment is easy. It is possible to maintain and stable operation.

12 and 13 are graphs showing vehicle movement when the extension length of the swinging buffer hole is 3 mm or more.

As shown in FIG. 12, even when the extension length C _t of the swing buffer hole 381 is 3 mm, it is easy to adjust because there is a neutral section, and the work can be stably maintained while the vehicle is in operation.

However, as shown in FIG. 13, when the extension length C _t of the swinging buffer hole 381 is 5 mm or more, the adjustment is easy because there is a neutral section, the swing motion becomes dull during the initial operation of the swing lever, If the slope at the starting point is large, there is a problem that the spiral phenomenon may occur.

Therefore, the extension length C _t of the swinging buffer hole 381 can be set to 0.5 to 6 mm, but more preferably, it is set to about 1.5 to 3 mm.

On the other hand, in the traveling HST 210 and the turning HST 310, a servo mechanism is provided so that the operating force can be more smoothly transmitted to each HST in the portion where the operation force of the peripheral speed lever 201 and the turning lever 301 is inputted Respectively.

1 and 2, each of the trunnion arms 270 and 370 is connected to the servo mechanisms 290 and 390. The servo mechanisms 290 and 390 are connected to the respective HSTs The operating force transmitted through the trunnion arms 270 and 370 of the HSTs 210 and 310 can be smoothly and accurately adjusted by using the hydraulic pressure so that the inclination angle of the swash plate provided to the hydraulic pump of each of the HSTs 210 and 310 .

Here, each of the servo mechanisms 290 and 390 is configured such that when each of the trunnion arms 270 and 370 is rotationally operated according to the operation of the peripheral speed lever 201 or the pivotal lever 301, And assist the operation of the mechanism connected between the trunnion arm 270 (370) and the pump.

Therefore, the servo mechanisms 290 and 390 must be operated so as to be accurately controlled in accordance with the operation force of the peripheral speed lever 201 or the pivotal lever 301, and the necessary control It is also desirable to perform a function of correcting when it is not precisely performed.

4, the servomechanism 390 provided in the HST 310 for turning is provided with a car for the left (?) Swing operation or the right (?) Swing operation from the neutral position of the trunnion arm 370 It is common to set the agitation pressure to be the same. However, when the left side? And right side? Pressure differences of the servo mechanism 390 for turning are set to be the same, when the actual vehicle is straightened or turned, fine, There is a problem such as turning further on either side during turning or turning operation.

Therefore, in consideration of this point, it is necessary for the servo mechanism 390 provided in the turning HST 310 to set the left (?) Or right (?) Differential pressure properly.

The charging pressure setting of the swing servo mechanism 390 is such that either one of the left and right pressures of the left side? And the right side? Is set to be higher than the other one of the right and left side pressures about the neutral position of the trunnion arm 370 desirable.

That is, when the servo mechanism 390 is turned in the left (alpha) direction, the? Side pressure of the servo servomotory 390 is lower than the? Side pressure and the right side? , The pressure on the side of β is set to a side pressure higher than the basic pressure of the charge.

For example, when turning in the left (alpha) direction, the pressure on the a side of the servo mechanism 390 is set to be lower by about 3 to 7 bar than the pressure on the side of beta, The pressure on the β side can be set 5 to 7 bar higher than the primary pressure. Under this condition, the charging pressure of the swing servo mechanism 390 can be set so that the left side (α) is about 20 bar and the right side (β) is about 25 bar when the basic pressure is about 19 bar around the neutral position.

On the contrary, the?,? Direction differential pressure of the servo servomotor 390 is lower than the? Differential pressure of the? Servo pressure of the swing servomechanism 390 at the time of turning in the right (?) Direction , And the pressure on the? Side when turning in the left (?) Direction can be set to a leaning pressure higher than the differential basic pressure.

It is preferable that the parking pressure setting of the swing servo mechanism 390 is appropriately corrected in consideration of the center of gravity of the vehicle, the balance of both wheels or the crawler, and the like.

That is, the method of correcting the parking pressure of the swing servomechanism 390 is performed by referring to the turning behavior of the vehicle when the vehicle does not travel straight ahead and tilts (or turns) to either side through the linearity test of the vehicle.

3, the pressure difference between the left side? And the right side? Of the trunnion arm 270 is maintained at the same or similar pressure with respect to the neutral position of the trunnion arm 270 It is preferable to set it.

For example, it is preferable that the differential pressure of? And? Centered on the neutral position of the trunnion arm 270 is set so as to remain similar or within? 5 bar at the basic pressure of charge.

By setting the differential pressure of the servo mechanism 390 for turning as described above, it is useful to improve the straightness of the vehicle. The same or similar setting of the differential pressure of the servomotor 290 can be used to maintain the neutral state when the vehicle is stopped.

As described above, the technical ideas described in the embodiments of the present invention can be implemented independently of each other, and can be implemented in combination with each other. While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. It is possible. Accordingly, the technical scope of the present invention should be determined by the appended claims.

100: transmission device 150: drive output shaft
200: traveling operation transmitting device 201: peripheral speed lever
210: HST for traveling 220: Potentiometer for driving
230: a traveling operation motor 235: a traveling motor arm
240: first transmission rod 250: arm unit
260: second transmission rod 270: trunnion arm for traveling
280: traveling buffer connection part 281: traveling buffer hole
285: Driving buffer pin 290: Driving servo mechanism
300: turning operation transmitting device 301: turning lever
310: HST 320 for turning: Potentiometer for turning
330: Operation motor for turning 335: Motor arm for turning
360: Turning transfer rod 370: Trunnion arm for turning
380: Buffer connection part for swinging 381: Buffer hole for swinging
385: Buffer for rotation 390: Servo mechanism for turning

Claims (6)

A trunnion arm for inputting an operation force corresponding to an operation of the turning operation mechanism to the HST for turning and a swing servo mechanism for transmitting an operation force inputted through the trunnion arm to the interior of the HST using the hydraulic pressure;
Wherein the servo mechanism for pivoting is configured such that either one of the differential pressure between the neutral position of the trunnion arm and the differential pressure for the left (?) Swing operation and the right (?) Swing operation is greater than the other differential pressure And the HST driving force transmitting device of the working vehicle. The method according to claim 1,
When the rotary servo mechanism is rotated in the left (alpha) direction, the difference between the a and b values is smaller than the difference between the a and b values, Wherein the pressure difference between the first and second pressure chambers is set to be a one-side pressure higher than the primary pressure. The method according to claim 1,
The?,? Direction differential pressure of the servo mechanism for pivoting is lower than the? Difference pressure of? On the? -Position servo mechanism of the pivoting servo mechanism when turning in the right (?) Direction, Wherein the pressure in the a side is set to a unilateral pressure higher than the basic pressure of the charge. The method according to claim 1,
The differential pressure difference between the α and β directions of the servo mechanism for pivoting is set to be lower by about 3 to 7 bar than the β differential pressure when the swinging motion is in the left direction α direction, And the β side pressure of the servo mechanism is set to be 5 to 7 bar higher than the primary pressure. The method according to any one of claims 1 to 4,
A driving trainer arm for inputting operation force according to the operation of the levers in the vicinity to the driving HST and a driving servomechanism for transmitting operation force inputted through the driving trainer arm to the inside of the driving HST by using the hydraulic pressure ;
Wherein the driving servomechanism is set such that the difference between the differential pressure of forward (?) And reverse (?) Differential pressure is set to be the same around the neutral position of the trunnion arm. The method of claim 5,
Characterized in that the differential pressure between the α and β of the servomotor for running is set to ± 5 bar at the basic pressure of the charge.

Images