JP2007010061A - Travel speed variable device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To promptly increase the speed of a vehicle body to the reverse direction and improve working efficiency in such a working form that forward working travel and reverse non-working travel are repeated, e.g. <P>SOLUTION: This travel speed variable device comprises a hydraulic continuously variable transmission device 3 consisting of a variable displacement hydraulic pump 1 and a variable displacement hydraulic motor 2. Herein, a linkage means 5 is provided for linkage to increase the speed of the output rotation of the hydraulic motor 2 in a positive/reverse direction by increasing the amount of oil to be discharged from the hydraulic pump 1 with an increase of a forward/reverse variable speed control input from a neutral region of a variable speed operation tool 4 and to increase the speed of the output rotation of the hydraulic motor 2 in relation to the reverse operation of the variable speed operation tool 4 in the reverse direction at a speed increasing rate greater than a speed increasing rate by an increase in the amount of oil to be discharged from the hydraulic pump 1. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a travel transmission used for a vehicle such as a combine.

  Conventionally, in a working vehicle such as a combine, for example, a hydraulic continuously variable transmission is continuously shifted in the forward / reverse direction by a forward / backward tilting operation of a shift lever, and forward and backward travel is performed. When switching from a traveling state to a reverse traveling state in which the vehicle travels without performing work, it has been desired to improve the work efficiency by moving the advancing backward in an agile manner.

Therefore, for example, as shown in Patent Document 1, in a hydraulic continuously variable transmission that transmits a traveling device, a gear that shifts sequentially from a neutral position to a forward side and a reverse side to shift to a high speed transmission ratio. A technique has been attempted in which the forward shift operation angle of the lever required to change the transmission ratio of the hydraulic continuously variable transmission by a constant ratio is set larger than the reverse shift operation angle.
Japanese Utility Model Publication No. 5-19639

  However, in the configuration described in Patent Document 1 described above, the hydraulic motor side of the hydraulic continuously variable transmission is not provided with a transmission means, and the output rotation of the hydraulic motor is increased by increasing the amount of oil discharged from the hydraulic pump. There is no means to increase speed other than speed.

  Therefore, in order to obtain the output rotation of the hydraulic motor according to the operation amount of the speed change lever, the link ratio of the link mechanism that links from this speed change lever to the swash plate angle adjustment arm that adjusts the discharge oil amount of the hydraulic pump, It must be changed and set between the forward side and the reverse side.

  If such a measure is not taken, when the shift lever is operated backward by a certain amount, the shift lever can be driven backward only at the same speed as when the shift lever is operated forward by the same amount. Improve work efficiency.

In order to solve the above-mentioned problems, the present invention takes the following technical means.
That is, according to the first aspect of the present invention, a hydraulic continuously variable transmission (3) is constituted by a variable displacement hydraulic pump (1) and a variable displacement hydraulic motor (2), and a transmission operation tool (4). As the amount of oil discharged from the hydraulic pump (1) increases in response to an increase in the forward / reverse shift operation amount from the neutral range, the output rotation of the hydraulic motor (2) is increased in the forward / reverse direction. In the reverse direction, the output rotation of the hydraulic motor (2) is reversed with a speed increase amount greater than the speed increase amount due to the increase in the discharge oil amount of the hydraulic pump (1) in relation to the reverse operation of the speed change operation tool (4). The present invention is a travel transmission device characterized in that a connecting means (5) capable of increasing the speed is provided.

  Thus, when the transmission operating tool 4 is operated from the neutral range to the forward side, the amount of oil discharged from the hydraulic pump 1 increases, and the output rotation of the hydraulic motor 2 that receives this oil discharge increases in the forward rotation direction. The vehicle body equipped with the transmission is accelerated in the forward direction. On the other hand, when the speed change operation tool 4 is operated from the neutral range to the reverse side, the amount of oil discharged from the hydraulic pump 1 increases, and the output rotation of the hydraulic motor 2 is caused by the increase in the amount of oil discharged from the hydraulic pump 1 by the connecting means 5. The vehicle speed is increased in the reverse direction by a speed increase amount greater than the speed increase amount, and the vehicle body equipped with the traveling transmission is speedily increased in the reverse direction.

  According to a second aspect of the present invention, a hydraulic continuously variable transmission (3) is constituted by a variable displacement hydraulic pump (1) and a variable displacement hydraulic motor (2), and a transmission operation tool (4). Output of the hydraulic motor (2) by adjusting the swash plate angle of the hydraulic pump (1) in accordance with an increase in the forward / reverse speed change operation amount from the neutral range, and increasing the amount of oil discharged from the hydraulic pump (1). The hydraulic motor (2) is linked to increase the rotation speed in the forward / reverse direction and automatically adjusts the swash plate angle of the hydraulic motor (2) in relation to the reverse operation of the speed change operation tool (4). Characterized in that there is provided linking means (5) capable of increasing the output rotation of 2) in the reverse direction by a speed increase amount larger than the speed increase amount by adjusting the swash plate angle of the hydraulic pump (1). This is a traveling transmission device.

  Accordingly, when the speed changer 4 is operated from the neutral range to the forward side, the swash plate angle of the hydraulic pump 1 increases, the amount of oil discharged from the hydraulic pump 1 increases, and the output of the hydraulic motor 2 that receives this discharged oil. The rotation speed is increased in the forward direction, and the vehicle body on which the traveling transmission is mounted is increased in the forward direction. On the other hand, when the speed change operation tool 4 is operated from the neutral region to the reverse side, the swash plate angle of the hydraulic pump 1 increases, the amount of oil discharged from the hydraulic pump 1 increases, and the swash plate of the hydraulic motor 2 is connected by the connecting means 5. The angle is automatically reduced, and the output rotation of the hydraulic motor 2 is increased in the reverse direction by a speed increase amount larger than the speed increase amount by the increase in the discharge oil amount of the hydraulic pump 1, and this traveling transmission device is mounted. The vehicle body that moves is agilely accelerated in the reverse direction.

  According to the first aspect of the invention, the reverse rotation direction of the output rotation of the hydraulic motor 2 is increased by a speed increase amount greater than the speed increase amount due to the increase in the discharge oil amount of the hydraulic pump 1 by the reverse operation of the speed change operation tool 4. The vehicle body equipped with this travel transmission can be speedily accelerated in the reverse direction. For example, the work efficiency can be improved in a work mode in which the forward travel and the non-work travel are repeated. Can be made.

  According to the second aspect of the present invention, the output rotation of the hydraulic motor 2 is discharged from the hydraulic pump 1 by automatically adjusting the swash plate angle of the hydraulic motor 2 linked to the reverse operation of the speed change operation tool 4. It is possible to increase the speed in the reverse direction with a speed increase amount larger than the speed increase amount due to the increase in the oil amount, and to quickly increase the speed of the vehicle body equipped with this travel transmission device in the reverse direction. The work efficiency can be improved in a work form that repeats non-work travel by reverse travel.

An embodiment of a traveling transmission apparatus according to the present invention will be described by exemplifying a self-detaching combine.
As shown in FIGS. 1 and 2, this combine is equipped with a steering unit 8, a threshing device 9, and a grain storage device 10 on the upper side of the left and right traveling devices 7, 7 wound around the crawler 6, A reaping device 11 is provided on the front side of the threshing device 9 so as to be adjustable up and down by an expansion and contraction operation of a hydraulic cylinder 12 for reaping and lifting.

  The harvesting device 11 supports the rear upper end portion of the post-cutting frame 13 on the upper portion of the mowing suspension stand 13 erected on the front portion of the machine body so as to be rotatable up and down. In addition, a pre-cutting processing device including a weed cocoon 14, a pulling device 15, a scraping device 16, a stock transporting device 17, and a cutting blade device 18 is provided.

  The threshing device 9 includes a handling cylinder 19 and a processing cylinder 20 that are internally pivoted in an upper handling chamber, a dust exhaust fan 21 that is pivoted on the rear side of the handling chamber, and a swing sorting that is built in a lower sorting chamber. It comprises a shelf 22, a red pepper 23, a first spiral 24, a second spiral 25, a first cereal spiral 26 linked to the first spiral 24, and a second cereal spiral 27 linked to the second spiral 25. .

  The grain storage device 10 includes a bottom conveying spiral 28 pivoted on the bottom of the tank body, a cerealing spiral 29 for cerealing grains on the rear side of the tank body in conjunction with the bottom conveying spiral 28, and the lifting It comprises a discharge spiral 30 that is interlocked with the upper end of the grain spiral 29 so as to be pivotable up and down.

  The left and right traveling devices 7 and 7 wind left and right crawlers 6 and 6 around left and right drive wheels 32 and 32 driven from a mission case 31 and a plurality of rolling wheels 33 and 33 arranged behind the left and right drive wheels 32 and 32. Configure.

  As shown in FIG. 2, in the transmission case 31, an auxiliary transmission gear 35 is provided so as to be slidable only in the axial direction with respect to the upper input shaft 34. By selectively meshing with a group of transmission gears 37 fixed to the intermediate shaft 36 disposed on the side, a three-stage auxiliary transmission mechanism 38 of high speed (running), medium speed (standard), and low speed (slope) is provided. Constitute. The auxiliary transmission gear 35 is slid by a forward / backward tilting operation of an auxiliary transmission lever 39 provided in the control unit 8. Further, the output gear 40 fixed to the intermediate shaft 36 is meshed with a center gear 42 provided at the center of the lower side clutch shaft 41, and left and right side clutch gears 43, 43 are provided on the left and right sides of the center gear 42, respectively. The side brakes 44, 44 are disposed outside the left and right side clutch gears 43, 43 so as to be slidably engaged and disengaged. Further, the wheel gears 46, 46 fixed to the inner ends of the left and right axles 45, 45 provided on the lower side are meshed with the left and right side clutch gears 43, 43. The drive wheels 32, 32 are fixed to the outer ends of the left and right axles 45, 45.

  Further, a branch transmission case 47 is attached to the upper outer side of the transmission case 31, and a gear 48 fixed to the protruding end side of the input shaft 34 and an intermediate feed chain drive shaft 49 in the branch transmission case 47. A fixed intermediate gear 50 and a gear 52 provided on a spline-connected shaft of an output shaft 51 of a hydrostatic continuously variable transmission (hydraulic continuously variable transmission) 3 are provided.

  A cutting output pulley 54 is attached to the protruding end of the input shaft 34 at the top of the transmission case 31 via a one-way clutch 53, while a cutting input pulley arranged at the rear upper end of the post-cutting frame 13 in the cutting device 11. A tension type cutting clutch is formed by winding a cutting transmission belt 56 between the belt and the belt 55. A feed chain output pulley 57 is attached to the protrusion of the feed chain drive shaft 49, and a transmission belt 61 is wound between the input pulley 60 attached to the inner end of the feed chain transmission shaft 58 via a one-way clutch 59. The feed chain clutch 63 is configured by providing a tension roller 62 for applying tension to the transmission belt 61.

  The hydrostatic continuously variable transmission 3 is attached to the inside of the upper part of the branch transmission case 47. As shown in FIG. 3, the hydrostatic continuously variable transmission 3 receives a plunger-type hydraulic pump 1 that is driven by an input shaft 64 and discharges hydraulic oil, and receives and outputs oil discharged from the hydraulic pump 1. A closed circuit is formed by connecting the plunger-type hydraulic motor 2 that drives and rotates the shaft 51 with a high pressure oil passage 65 on the forward side (forward rotation side) and a low pressure oil passage 66 on the reverse side (reverse rotation side). This is the configuration. Further, the high pressure oil passage 65 and the low pressure oil passage 66 are short-circuited by an oil passage in which a check valve 67 and a throttle valve 68 are connected in series, and from each of the high pressure oil passage 65 and the low pressure oil passage 66. A relief valve 71 is connected to a lower charge oil passage 72 through reverse check valves 69 and 70. The charge oil passage 72 is for replenishing the aforementioned closed circuit leak oil from the oil tank 73. The hydraulic pump 1 and the hydraulic motor 2 are configured such that the displacement of the plunger and the amount of discharged oil can be changed by adjusting the angle of the internal swash plate, and the hydraulic pressure can be changed. The swash plate angle of the pump 1 is mechanically linked so as to be changed via the link mechanism by the forward and backward tilting of the main transmission lever 4 provided in the control unit 8. The swash plate angle of the hydraulic motor 2 is configured to be operated via the interlocking rod 75 by the operation of the electric motor type HST motor swash plate switching actuator 74.

  Further, a cooling fan 76 for the hydrostatic continuously variable transmission 3 is attached to the projecting end of the input shaft 64 of the hydrostatic continuously variable transmission 3, An input pulley 80 to which driving force is input from an output shaft 77 of the engine E via an output pulley 78 and a transmission belt 79 is attached. Further, from the threshing output pulley 81 attached to the output shaft 77 through the belt transmission mechanism 82, the handling cylinder 19, the processing cylinder 20, the dust exhaust fan 21, the swing sorting shelf 22, the red pepper 23, the first spiral 24, The second spiral 25 is configured to be driven in conjunction. Further, the bottom conveying spiral 28 is driven in conjunction with a discharge output pulley 83 attached to the output shaft 77 via a belt transmission mechanism 82 and the like.

  Further, the auxiliary transmission shifter 85 that slides the auxiliary transmission gear 35 from the auxiliary transmission lever 39 standing on the side operation pad 85 of the control unit 8 via the auxiliary transmission rod 84 is configured to rotate. In addition, the swash plate angle of the hydraulic pump 1 of the hydrostatic continuously variable transmission 3 is operated from the main transmission lever 4 through the main transmission rod 86. Further, a sub-shift running shift sensor 87 for detecting the operation position of the sub-transmission lever 39 is provided at the base of the sub-transmission lever 39, and the main transmission lever 4 is tilted in the backward direction at the base of the main transmission lever 4. A reverse detection sensor 88 for detecting the movement and a cutting clutch engaging sensor 90 for detecting that the cutting clutch lever 89 has been operated to the input side are provided at the base of the cutting clutch lever 89. Further, a cutting height detection sensor 91 for detecting the height of the cutting device 11 with respect to the airframe from the amount of vertical rotation of the post-cutting frame 13 is provided.

  As shown in FIG. 4, on the input side of the controller 92, the reverse detection sensor 88, the reverse speed setting dial 93 provided on the front operation panel of the control unit 8, the auxiliary shift travel shift sensor 87, the cutting While the clutch engagement sensor 90 and the cutting height detection sensor 91 are connected, the HST motor swash plate switching actuator 74 is connected to the output side of the controller 92. This is the connecting means 5.

  With the above configuration, when the main speed change lever 4 is operated forward, the swash plate angle of the hydraulic pump 1 of the hydrostatic continuously variable transmission 3 is increased via the main speed change rod 86 and the amount of discharged oil is increased. As the amount of oil supplied to the hydraulic motor 2 increases, the output shaft 51 of the hydraulic motor 2 increases in the forward direction, and the combine increases in the forward direction.

  On the other hand, when the main speed change lever 4 is operated to the reverse side, this operation state is detected by the reverse detection sensor 88, and an output from the controller 92 to the HST motor swash plate switching actuator 74 is made. As a result, the amount of oil required for one rotation decreases, and as a result, the output shaft 51 of the hydraulic motor 2 increases in the reverse direction, and the combine increases in the reverse direction.

  Accordingly, the swash plate angle of the hydraulic motor 2 is reduced during reverse travel, so that the output shaft 51 of the hydraulic motor 2 can be obtained even when the operation angle of the main shift lever 4 toward the forward side and the operation angle toward the reverse side are the same. The output rotational speed of the rear side is larger than the forward side. Thus, when the operation angle of the main shift lever 4 toward the forward side and the operation angle toward the reverse side are the same, the reverse travel speed becomes larger than the forward travel speed.

This state is shown in FIG.
FIG. 5 is a graph in which the horizontal axis is the tilting operation position of the main shift lever 4 and the vertical axis is the vehicle speed. On the forward travel side, the sub-shift (running), the sub-shift (standard), and the sub-shift (slope) ), The vehicle speed increases linearly at different fixed speed ratios. On the other hand, on the reverse travel side, the vehicle speed is constant as shown by the solid line, regardless of whether the sub-shift is the sub-shift (travel), the sub-shift (standard), or the sub-shift (slope). The ratio increases linearly, and this increase ratio is equivalent to the sub-shift (travel) on the forward travel side. The vehicle speed when the main transmission lever 4 is in the forward highest speed position and the vehicle speed when the main transmission lever 4 is in the reverse highest speed position are set to be substantially the same. In addition, by making the maximum reverse speed at the sub-shift (travel) and the maximum reverse speed at the sub-shift (standard) substantially the same, the driver's speed sensation becomes substantially constant regardless of the sub-shift position. Increased safety.

  Further, by operating the reverse speed setting dial 93, it is possible to arbitrarily change the speed increase ratio of the vehicle speed on the reverse travel side. That is, the gradient of the solid line in FIG. 5 can be arbitrarily changed. Thereby, the speed increase rate of the reverse speed can be adjusted according to the skill level of the operator, and the safety and work efficiency can be improved. Note that the change range of the gradient of the solid line may be regulated to a predetermined width.

  The reverse speed setting dial 93 may be disposed on the front operation panel of the control unit 8 between a steering operation lever standing at a position closer to the outside and a central monitor. In addition, characters “high”, “medium”, and “low” are displayed along the periphery of the dial.

  When the auxiliary transmission lever 39 is operated to the “travel” position, this operation position is detected by the auxiliary transmission movement shift sensor 87, and the main transmission lever 4 is operated to the reverse side as described above. Further, the output from the controller 92 to the HST motor swash plate switching actuator 74 is restricted, and the swash plate angle of the hydraulic motor 2 is controlled so as not to become small or only small. As a result, the speed increase ratio at the time of reverse travel is suppressed to avoid the danger of high speed reverse travel, and the combine travels while suppressing the decrease in the output torque of the hydraulic motor 2 due to the swash plate angle of the hydraulic motor 2 becoming smaller. It is possible to prevent the situation from being impossible.

  Further, as shown in FIG. 6, when the vehicle is moving backward, the controller 92 controls the HST motor swash plate so that the speed increase ratio in the case of the sub-shift (slope) matches the speed increase ratio in the case of the sub-shift (standard). An output to the switching actuator 74 may be set. As a result, the reverse travel speed due to the sub-shift (slipping) becomes the same as the reverse travel speed due to the sub-shift (standard), and the work efficiency can be improved. Further, the reverse travel speed may be switched to a plurality of stages in the sub-shift (standard) or sub-shift (slope) state. By arbitrarily switching the reverse speed to multiple stages in this way, the work can be performed safely and efficiently according to the level of proficiency of the pilot. If the reverse travel speed is switched to a two-stage switch, it is easy for the driver to understand. , The operator can operate without confusion.

  If the reverse speed setting dial 93 is provided on the inner side surface portion of the grip portion of the main transmission lever 4, the inner surface portion of the grip portion of the auxiliary transmission lever 39, or the upper surface portion of the steering lever, in addition to the aforementioned front operation panel, The operability can be further improved.

It is a side view for description of a combine. It is explanatory drawing of the transmission mechanism of a combine. 1 is a hydraulic circuit diagram of a hydrostatic continuously variable transmission. It is a control block diagram of a connection means. It is a graph which shows the relationship between the operation angle of a main speed-change lever, and a vehicle speed. It is a graph which shows the relationship between the operation angle of the main transmission lever in another Example, and a vehicle speed. It is a graph which shows the relationship between the operation angle of the main transmission lever in a prior art, and a vehicle speed.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hydraulic pump 2 Hydraulic motor 3 Hydraulic continuously variable transmission (hydrostatic continuously variable transmission)
4 Shifting operation tool (main shifting lever)
5 Connection means

Claims (2)

  The variable displacement hydraulic pump (1) and the variable displacement hydraulic motor (2) constitute a hydraulic continuously variable transmission (3), and the forward / reverse shift operation amount from the neutral range of the transmission operation tool (4). The hydraulic pump (1) is connected to increase the output oil amount in the forward / reverse direction by increasing the amount of oil discharged from the hydraulic pump (1) in accordance with the increase in the reverse speed of the shift operation tool (4). Linking means that can increase the output rotation of the hydraulic motor (2) in the reverse direction with a speed increase larger than the speed increase due to the increase in the amount of oil discharged from the hydraulic pump (1) in relation to the operation. 5) A traveling transmission apparatus characterized by comprising:   The variable displacement hydraulic pump (1) and the variable displacement hydraulic motor (2) constitute a hydraulic continuously variable transmission (3), and the forward / reverse shift operation amount from the neutral range of the transmission operation tool (4). The swash plate angle of the hydraulic pump (1) is adjusted in accordance with the increase of the hydraulic pump to increase the amount of oil discharged from the hydraulic pump (1) to increase the output rotation of the hydraulic motor (2) in the forward and reverse directions. And the swash plate angle of the hydraulic motor (2) is automatically adjusted in association with the reverse operation of the speed change operation tool (4) to control the output rotation of the hydraulic motor (2) to the hydraulic pump ( 1. A traveling transmission comprising a connecting means (5) capable of increasing the speed in the reverse direction by a speed increasing amount larger than the speed increasing amount by adjusting the swash plate angle of 1).

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