JP2023112720A - Planetary gear assembly, HMT device and transmission structure - Google Patents

Abstract

To provide a planetary gear assembly capable of reducing the size of the entire device, while expanding a shift range of an HMT device formed in cooperation with an HST.SOLUTION: A planetary gear assembly comprises: a transmission shaft; first and second planetary gear mechanisms in which a sun gear is supported on the transmission shaft so as not to be relatively rotatable around an axial line; and a connection member externally fitted on the transmission shaft so as to be relatively rotatable around the axial line. The connection member connects planetary elements other than the sun gear and a planetary element forming a reference rotational speed power input part of the first planetary gear mechanism, and planetary elements other than the sun gear and the planetary element forming the reference rotational speed power input part of the second planetary gear mechanism so as not be relatively rotatable with each other around the axial line.SELECTED DRAWING: Figure 1

Description

The present invention relates to a planetary gear assembly having two planetary gear mechanisms, a hydrostatic mechanical continuously variable transmission (HMT device) including the planetary gear assembly, and a transmission structure including the HMT device.

Various HMT devices, which are a combination of a hydrostatic continuously variable transmission mechanism (HST) and a planetary gear mechanism, have been proposed and are suitably used in the transmission structure of working vehicles such as combine harvesters and tractors.

For example, Patent Document 1 below describes an HST in which a pump shaft is operatively connected to a drive source and a motor shaft is arranged parallel to the pump shaft, and an HST which is coaxially connected to the pump shaft so as not to rotate relative to the axis. a drive shaft; a first transmission shaft coaxially connected to the motor shaft so as not to rotate relative to the axis; a second transmission shaft arranged parallel to both the drive shaft and the first transmission shaft; A first planetary gear mechanism having one sun gear, a first carrier and a first internal gear, and arranged coaxially with the first transmission shaft; and a second sun gear, a second carrier and a second internal gear. a second planetary gear mechanism arranged coaxially with the second transmission shaft; an output shaft arranged coaxially with the second transmission shaft in a relatively rotatable state; and first to fourth clutches. mechanism (hereinafter referred to as the first conventional example) is disclosed.

A first sun gear is supported by the first transmission shaft so as not to rotate relative to the axis, a first carrier is operatively connected to the first transmission shaft (that is, the motor shaft) via the first clutch mechanism, and It is operatively connected to the drive shaft (that is, the pump shaft) through the second clutch mechanism, and the first internal gear is operatively connected to the output shaft.

The second internal gear is operatively connected to the drive shaft (that is, the pump shaft) via the third clutch mechanism, and the second carrier is connected to the first transmission shaft via the fourth clutch mechanism. (that is, the motor shaft), a second sun gear is supported by the second transmission shaft so as not to be relatively rotatable about its axis, and the second transmission shaft is operatively connected to the output shaft.

The first conventional example has a first transmission state in which the first clutch mechanism is in the engaged state and the second to fourth clutch mechanisms are in the released state, and a first transmission state in which the second clutch mechanism is in the engaged state and the a second transmission state in which the first, third and fourth clutch mechanisms are in the released state; and a second transmission state in which the third and fourth clutch mechanisms are in the engaged state and the first and second clutch mechanisms are in the released state. 3 transmission states can be selectively revealed.

In the first transmission state, the HST output from the motor shaft is input to both the first sun gear and the first carrier, and rotational power is output from the first internal gear to the output shaft.

In the second transmission state, the reference rotational speed power from the drive source is input to the first carrier, the HST output from the motor shaft is input to the first sun gear, and the first internal gear is transmitted to the first sun gear. A synthetic rotational power generated by the planetary gear mechanism is output to the output shaft.

In the third transmission state, the reference rotational speed power from the drive source is input to the second internal gear, the HST output from the motor shaft is input to the second carrier, and the second sun gear is applied to the second gear. Synthetic rotational power generated by the planetary gear mechanism is output to the second transmission shaft and transmitted to the output shaft.

The first conventional example having such a configuration is useful in that it can widen the speed change range of the rotational speed that can be produced by the output shaft. (the drive shaft, the first transmission shaft, and the second transmission shaft) are required, and a gear train for power transmission between the three shafts is also required. And there is room for improvement in terms of cost.

Further, in Patent Document 2 below, a drive shaft operatively connected to a drive source and a pump shaft are operatively connected to the drive shaft in a state arranged parallel to the drive shaft, and a motor shaft is operatively connected to the drive shaft. and the HST arranged parallel to the two shafts at a displaced position from the pump shaft, and the drive shaft, the pump shaft and the motor shaft arranged at a displaced position parallel to these axes. A first planetary gear mechanism having a first transmission shaft, a first sun gear, a first carrier and a first internal gear, and arranged coaxially with the first transmission shaft, and coaxially with the first planetary gear mechanism a first intermediate shaft disposed above, a second transmission shaft coaxially connected to the motor shaft so as not to rotate relative to the axis, a second sun gear, a second carrier, and a second internal gear, a second planetary gear mechanism arranged coaxially with the second transmission shaft; a second intermediate shaft arranged coaxially with the second planetary gear mechanism; an output shaft; and the output from the first intermediate shaft An HMT device comprising a first clutch mechanism for engaging and disengaging power transmission to a shaft and a second clutch mechanism for engaging and disengaging power transmission from the second intermediate shaft to the output shaft (hereinafter referred to as the second conventional example). ) has been disclosed (see FIG. 1 of Patent Document 2, etc.).

The second conventional example requires a large number of shafts including the drive shaft, the first transmission shaft, the second transmission shaft, the first intermediate shaft, and the second intermediate shaft. It is very disadvantageous in terms of cost.

Furthermore, Patent Document 2 also discloses an HMT device (hereinafter referred to as a third conventional example) including an HST and first and second planetary gear mechanisms arranged in series (see Patent Document 2). Figure 5, etc.).

In the third conventional example as well, the drive shaft is coaxially connected to the pump shaft so as not to rotate relative to the axis, and the first and second planetary gears are connected to the motor shaft so that they cannot rotate relative to the axis. Three shafts, including a transmission shaft that supports the gear mechanism and the first to third clutch mechanisms, and an output shaft that is operatively connected to the transmission shaft via a gear train, are arranged in an overlapping state with respect to the axial direction. Therefore, there is room for improvement in terms of installation space, transmission efficiency and cost.

Japanese Patent No. 4194709 International Publication WO2020/097650

The present invention has been devised in view of the prior art described above, and is a planetary gear assembly that forms an HMT device in cooperation with an HST. It is a primary object to provide a planetary gear assembly that obtains.

A second object of the present invention is to provide an HMT device including an HST and first and second planetary gear mechanisms, which is capable of widening the shift range of the HMT output and reducing the size of the HMT device. .

Further, the present invention provides a transmission structure including an HMT device including an HST and first and second planetary gear mechanisms, which can reduce the size of the HMT device while increasing the shift range of the HMT output. A third object of the present invention is to provide a transmission structure capable of outputting an HMT output with good controllability.

In order to achieve the first object, the first aspect of the present invention provides that the reference rotational speed power operatively input from the drive source to the pump shaft is, for example, the first HST speed, which is the highest speed on the reverse rotation side, and the forward rotation speed, for example. A planetary gear assembly that forms an HMT device in cooperation with an HST that continuously shifts between a second HST speed, which is the maximum side speed, and outputs the HST output after shifting from a motor shaft, comprising: a transmission shaft; It has three planetary elements including one sun gear, a first carrier and a first internal gear, the first sun gear is supported by the transmission shaft so as not to rotate relative to the axis, and one of the first carrier and the first internal gear is A first planetary gear mechanism forming a reference rotational speed power input section capable of inputting reference rotational speed power; A sun gear is supported by the transmission shaft so as to be axially non-rotatable, and the planetary element is different from the planetary element forming the reference rotational speed power input portion of the first planetary gear mechanism, out of the second carrier and the second internal gear. a second planetary gear mechanism forming a reference rotational speed power input portion capable of inputting reference rotational speed power; The planetary elements other than the first sun gear and the planetary elements forming the reference rotational speed power input portion of the first planetary gear mechanism, and the second sun gear and the reference rotational speed power input portion of the second planetary gear mechanism. To provide a planetary gear assembly that connects planetary elements other than planetary elements to be formed so as not to be relatively rotatable about an axis.

In one form of the first aspect, the transmission shaft can be operatively input with an HST output.
In this case, the connecting member includes a planetary element other than the first sun gear and the planetary element forming the reference rotation speed power input section of the first planetary gear mechanism, and a second sun gear and the reference gear of the second planetary gear mechanism. It has a connecting body for connecting planetary elements other than the planetary elements forming the rotational speed power input section, and an output body capable of outputting the rotational power of the connecting body to the outside.

In another form of the first aspect, the connecting member is operatively capable of receiving an HST output.
In this case, the transmission shaft can output rotational power around its own axis to the outside.

In still another form of the first mode, the transmission shaft is a cylindrical shaft to which an HST output can be operatively input, and the planetary gear assembly has the transmission shaft externally rotatable about an axis. An output shaft is provided for insertion.
In this case, the connecting member includes a planetary element other than the first sun gear and the planetary element forming the reference rotation speed power input section of the first planetary gear mechanism, and a second sun gear and the reference gear of the second planetary gear mechanism. A connecting body for connecting planetary elements other than the planetary elements forming the rotation speed power input section, and an output body capable of outputting the rotational power of the connecting body to the outside, wherein the output body is the output shaft. on the same axis and cannot rotate relative to each other around the axis.

In order to achieve the first object, the second aspect of the present invention provides a first HST speed in which the reference rotational speed power operatively input from the drive source to the pump shaft is, for example, the maximum speed on the reverse rotation side, and a forward speed. A planetary gear assembly forming an HMT device in cooperation with an HST that continuously shifts between a second HST speed, which is the maximum speed on the rolling side, and outputs the HST output after shifting from a motor shaft, wherein the HST output is A transmission shaft that is operably inputtable, a first element that is supported by the transmission shaft so as not to rotate relative to the axis, a second element that is capable of receiving a reference rotational speed power, and the first and second elements. A first planetary gear mechanism having a third element for outputting a combined rotational power obtained by synthesizing the rotational power input to the first planetary gear mechanism; A second planetary gear mechanism having a second element and a third element that outputs combined rotational power obtained by synthesizing the rotational power input to the first and second elements, and relative rotation around the axis with the transmission shaft a connecting member that is freely externally inserted, the connecting member being a connecting body that connects the third elements of the first and second planetary gear mechanisms, and capable of outputting rotational power of the connecting body to the outside. and an output.

The planetary gear assembly according to the second aspect may preferably include an input member connected to the second element of the second planetary gear mechanism in a state in which it is rotatable relative to the transmission shaft about the axis.
The input member has first and second input gear portions capable of inputting reference rotational speed power, and the pitch diameter of the second input gear portion is larger than the pitch diameter of the first input gear portion. Small diameter.

In the first form of the second aspect, the first planetary gear mechanism includes a first sun gear acting as a first element, a first carrier acting as a third element, and a first inter-plane gear acting as a second element. The second planetary gear mechanism includes a second sun gear acting as a first element, a second carrier acting as a second element, and a second internal gear acting as a third element. shall have.

In this case, the first planetary gear mechanism rotates the first carrier in the first rotation direction, which is the one side around the axis, as the HST output changes from the first HST speed side to the second HST speed side under the transmission state. The first gear rotates at an accelerated speed, and the first carrier rotates in the first rotation direction at the predetermined first gear maximum speed when the HST output is set to the predetermined first gear maximum speed HST speed. A ratio is set.

In the second planetary gear mechanism, the second internal gear rotates in the first rotational direction at the first speed maximum speed when the HST output is set to the first speed maximum speed HST speed in the transmission state. Further, as the HST output changes from the HST speed for the highest speed of the first speed stage toward the first HST speed to the predetermined HST speed for the highest speed of the second speed stage, the rotation speed of the second internal gear changes to the first speed. The gear ratio is set so as to increase the speed from the stage maximum speed to the second stage maximum speed.

In the first form of the second aspect, preferably, the connecting body includes a cylindrical portion extending in the axial direction and extending radially outward from the first side in the axial direction of the cylindrical portion and connected to the first carrier. It may have a first flange and a second flange extending radially outwardly from an axially second side of the tubular portion and coupled to a second internal gear.

More preferably, the output body is arranged on the opposite side of the connecting body with respect to the axial direction across the first planetary gear supported by the first carrier, and rotates around the axis on the first side in the axial direction of the connecting body. It may have a connecting flange that is connected so as not to rotate relative to each other, and a shaft that extends from the connecting flange to the first side in the axial direction.

Preferably, the planetary gear assembly according to the second aspect may include a transmission gear member externally fitted on the shaft portion so as to be relatively rotatable around the axis.
The transmission gear member has an input gear portion for inputting the reference rotational speed power that is operationally input from the drive source, and an output gear portion that meshes with the first internal gear.

Preferably, the planetary gear assembly according to the second aspect is supported so as not to rotate relative to a portion of the transmission shaft that supports the second planetary gear mechanism on the second side in the axial direction, and is capable of receiving an HST output. and a HST driven gear.

In the second aspect, preferably, the first planetary gear mechanism is configured such that the third element becomes zero speed when the HST output is set to the predetermined HST speed for zero speed under the transmission state. A ratio is set.

More preferably, the HST speed for zero speed is a speed shifted from the first HST speed by a predetermined speed toward the second HST speed.

In order to achieve the first object, the third aspect of the present invention provides a first HST speed in which the reference rotational speed power operatively input from the drive source to the pump shaft is, for example, the maximum speed on the reverse rotation side and, for example, the forward speed. A planetary gear assembly that forms an HMT device in cooperation with an HST that continuously shifts between a second HST speed, which is the maximum speed on the rolling side, and outputs the HST output after shifting from a motor shaft, comprising: , a first planetary gear mechanism having a first element supported by the transmission shaft so as not to be relatively rotatable about the axis, a second element to which a reference rotational speed power can be input, and a third element to which an HST output can be input. and a second planetary gear having a first element supported by the transmission shaft so as not to rotate relative to the axis, a second element to which a reference rotational speed power can be input, and a third element to which an HST output can be input. a mechanism, and a connecting member externally fitted around the transmission shaft so as to be relatively rotatable about the axis, the connecting member being capable of receiving an HST output, and connecting the first and second planetary gear mechanisms. A planetary gear assembly configured to connect the third elements, wherein the transmission shaft serves as a common HMT output member for both the first and second planetary gear mechanisms.

In order to achieve the second object, the fourth aspect of the present invention provides a first HST speed in which the reference rotational speed power operatively input from the drive source to the pump shaft is set to, for example, the maximum speed on the reverse rotation side and, for example, the forward speed. an HST that continuously shifts between the second HST speed set as the maximum speed on the rolling side and outputs the HST output after shifting from the motor shaft; and a drive shaft to which the reference rotation speed power is operatively transmitted from the drive source , a transmission shaft, and three planetary elements including a first sun gear, a first carrier and a first internal gear, the first sun gear being supported by the transmission shaft so as not to rotate relative to the axis, the first carrier and the first A first planetary gear mechanism that forms a reference rotational speed power input section in which one of the internal gears is capable of inputting reference rotational speed power, and three planetary elements including a second sun gear, a second carrier, and a second internal gear. A second sun gear is supported by the transmission shaft so as not to rotate relative to the axis, and the second carrier and the second internal gear form a reference rotation speed power input part in the first planetary gear mechanism a second planetary gear mechanism forming a reference rotational speed power input section in which a planetary element different from the element is capable of inputting the reference rotational speed power; a first transmission gear train that can be operatively transmitted to a rotational speed power input portion; a first clutch mechanism that engages and disengages power transmission by the first transmission gear train; a second transmission gear train capable of operatively transmitting power to a reference rotation speed power input portion of a planetary gear mechanism; a second clutch mechanism for engaging and disengaging power transmission by the second transmission gear train; a connecting member that is rotatably externally inserted, wherein the connecting member includes a planetary element other than the first sun gear and the planetary element forming the reference rotational speed power input section of the first planetary gear mechanism; and the second planetary gear mechanism. Provided is an HMT device in which a second sun gear and a planetary element other than a planetary element forming a reference rotation speed power input section of a planetary gear mechanism are connected so as not to rotate relative to each other about an axis.

In one form of the fourth aspect, the transmission shaft can operatively receive an HST output.
In this case, the connecting member includes a planetary element other than the first sun gear and the planetary element forming the reference rotation speed power input section of the first planetary gear mechanism, and a second sun gear and the reference gear of the second planetary gear mechanism. It has a connecting body for connecting planetary elements other than the planetary elements forming the rotational speed power input section, and an output body capable of outputting the rotational power of the connecting body to the outside.

In another form of the fourth aspect, the connecting member is operatively capable of receiving an HST output.
In this case, the transmission shaft can output rotational power around its own axis to the outside.

In still another aspect of the fourth aspect, the transmission shaft is a cylindrical shaft to which an HST output can be operatively input, and the transmission shaft is fitted around the HMT device so as to be relatively rotatable about its axis. An output shaft is provided.
In this case, the connecting member includes a planetary element other than the first sun gear and the planetary element forming the reference rotation speed power input section of the first planetary gear mechanism, and a second sun gear and the reference gear of the second planetary gear mechanism. A connecting body for connecting planetary elements other than the planetary elements forming the rotation speed power input section, and an output body capable of outputting the rotational power of the connecting body to the outside, wherein the output body is the output shaft. on the same axis and cannot rotate relative to each other around the axis.

In order to achieve the second object, the fifth aspect of the present invention provides a first HST speed in which the reference rotational speed power operatively input to the pump shaft from the drive source is set to the maximum speed on the reverse rotation side and the forward speed. an HST that continuously shifts between the second HST speed set as the maximum speed on the rolling side and outputs the HST output after shifting from the motor shaft; and a drive shaft to which the reference rotation speed power is operatively transmitted from the drive source a transmission shaft to which the HST output is operatively transmitted from the motor shaft; a first element supported by the transmission shaft so as not to rotate relative to the axis; a second element to which a reference rotational speed power can be input; a first planetary gear mechanism having a third element for outputting combined rotational power obtained by synthesizing the rotational powers input to the first and second elements; a first transmission gear train capable of operatively transmitting power to two elements; a first clutch mechanism for engaging and disengaging power transmission by the first transmission gear train; a second planetary gear mechanism having an element, a second element to which reference rotational speed power can be input, and a third element that outputs combined rotational power obtained by synthesizing the rotational powers input to the first and second elements; a second transmission gear train capable of operatively transmitting the reference rotational speed power from the drive shaft to the second element of the second planetary gear mechanism; and a second clutch mechanism for engaging and disengaging power transmission by the second transmission gear train. and a connecting member for connecting the third elements of the first and second planetary gears so as not to rotate relative to each other about the axis, wherein the connecting member is fitted around the transmission shaft so as to rotate about the axis relative to each other. a connecting body whose first side in the axial direction is connected to the third element of the first planetary gear mechanism and whose second side in the axial direction is connected to the third element of the second planetary gear mechanism; and rotational power of the connecting body to the outside.

In the first form of the fifth aspect, the first planetary gear mechanism includes a first sun gear acting as a first element, a first carrier acting as a third element, and a first inter-plane gear acting as a second element. The second planetary gear mechanism includes a second sun gear acting as a first element, a second carrier acting as a second element, and a second internal gear acting as a third element. shall have.

In this case, in the first planetary gear mechanism, when the HST output is set to the predetermined HST speed for zero speed under the transmission state, the first carrier becomes zero speed, and the HST output changes from the first HST speed side to the second HST speed. When the first carrier rotates at an accelerated speed in the first rotational direction, which is one side of the axis, and the HST output reaches the predetermined HST speed for the highest speed of the first speed stage, the first A gear ratio is set such that one carrier rotates in a first rotational direction at a predetermined first gear maximum speed.

In the second planetary gear mechanism, the second internal gear rotates in the first rotational direction at the first speed maximum speed when the HST output is set to the first speed maximum speed HST speed in the transmission state. Further, as the HST output changes from the HST speed for the highest speed of the first speed stage toward the first HST speed to the predetermined HST speed for the highest speed of the second speed stage, the rotation speed of the second internal gear changes to the first speed. The gear ratio is set so as to increase the speed from the stage maximum speed to the second stage maximum speed.

In the first form of the fifth aspect, preferably, the connecting body includes a cylindrical portion extending in the axial direction and extending radially outward from the first side in the axial direction of the cylindrical portion and connected to the first carrier. and a second flange extending radially outward from the axial second side of the cylindrical portion and connected to the second internal gear.

In the first form of the fifth aspect, preferably, the drive shaft is coaxially connected to the pump shaft so as not to be relatively rotatable about an axis, the transmission shaft is arranged parallel to the drive shaft, and the A first transmission gear train includes: a first drive gear supported axially rotatably on the drive shaft; and a first transmission gear train operatively meshed with the first drive gear and non-rotatably axially relative to the first internal gear. and a first driven gear supported directly or indirectly on the transmission shaft in a connected state so as to be relatively rotatable about an axis, wherein the first clutch mechanism is adapted to provide a transmission from the drive shaft to the first drive gear. The second transmission gear train is provided on the drive shaft so as to engage and disengage power transmission, and the second transmission gear train operates on a second drive gear supported on the drive shaft so as to be relatively rotatable about the axis, and the second drive gear. a second driven gear directly or indirectly supported by the transmission shaft so as to be relatively rotatable about the axis in a state of being positively meshed and connected to the second carrier so as not to be relatively rotatable about the axis; A clutch mechanism is provided on the drive shaft for disengaging power transmission from the drive shaft to the second drive gear.

More preferably, the first and second clutch mechanisms are arranged so that a part of the first and second clutch mechanisms enters a space defined by an outer peripheral surface of the cylindrical portion and opposing surfaces of the first and second flanges. First and second clutch mechanisms are axially disposed between the first and second flanges of the coupling.

The HMT device according to the first form of the fifth aspect preferably comprises: a third transmission gear train capable of operatively transmitting the reference rotational speed power from the drive shaft to the second carrier; and the third transmission gear train and a third clutch mechanism for disengaging power transmission by means of.

The third transmission gear train includes a third driving gear supported by the driving shaft so as to be axially rotatable relative to each other, and is operatively meshed with the third driving gear and connected to the second carrier so as not to be relatively rotatable around the axis. and a third driven gear supported directly or indirectly on the transmission shaft so as to be relatively rotatable about the axis in a state where the second carrier is rotated at a higher speed than the second transmission gear train. is set.
The third clutch mechanism is provided on the drive shaft to engage and disengage power transmission from the drive shaft to the third drive gear.

More preferably, the HMT device according to the first form of the fifth aspect may include an input member connected to the second element of the second planetary gear mechanism in a state of being rotatable relative to the transmission shaft about the axis. .
The second and third driven gears are provided on the input member.

In order to achieve the third object, the sixth aspect of the present invention provides an HMT device according to various configurations of the first aspect of the fifth aspect and a shift operation range between the zero speed position and the maximum speed position. an operating position sensor for detecting the operating position of the gearshift operating member; a first clutch operating member for switching between engagement and disengagement of the first clutch mechanism; and engagement of the second clutch mechanism. a second clutch actuating member for switching disengagement operation; an HST actuating member for actuating an output adjusting member of the HST; an output sensor for directly or indirectly detecting the rotational speed of the connecting member; and the first and second clutches. a control device for controlling the operation of the operating member and the HST operating member, wherein the shift operation range is set to a range from the zero speed position to the maximum speed position of the first speed stage, and the first speed stage operation on the low speed side is set. and a second speed operation region on the high speed side set in a range from the first speed maximum speed position to the second speed maximum speed position, and the control device includes the shift operation member is operated in the first speed operation region, the first clutch mechanism is in the engaged state and the second clutch mechanism is in the disengaged state, and the shift operation member is in the first speed maximum speed position. When positioned, one of the first and second clutch mechanisms is engaged and the other is disengaged. actuating the first and second clutch actuating members so that the first clutch mechanism is in the disengaged state and the second clutch mechanism is in the engaged state, and in accordance with the operation of the shift operating member to the zero speed position; , the HST output becomes the HST speed for zero speed, and the HST output shifts from the first HST speed side to the second HST speed side in accordance with the operation of the shift operating member toward the speed increasing side within the first speed stage operation area. When the speed is changed and the shift operation member is operated to the first speed maximum speed position, the HST output becomes the HST speed for the first speed maximum speed, and the shift operation member is operated within the second speed speed operation region. The HST output is shifted from the 2nd HST speed side to the 1st HST speed side in accordance with the operation to the speed increasing side, and the HST output is shifted to the 2nd speed position in accordance with the operation of the shift operation member to the maximum speed position. A transmission structure is provided for actuating the HST actuating member so as to achieve the highest HST speed.

In one embodiment, the transmission structure includes a forward rotation output state in which the HMT power operatively input from the output body is output without changing the rotation direction, and a reverse rotation output state in which the HMT power is output after reversing the rotation direction. A forward/reverse switching mechanism that can selectively take an output state, and a forward/reverse actuating member that operates the forward/reverse switching mechanism.

In this case, the shift operation range of the shift operation member includes a forward operation range from the zero speed position to the forward maximum speed position and a reverse operation range from the zero speed position to the reverse maximum speed position. When the speed change operation member is positioned in the forward operation range, the control device places the forward/reverse switching mechanism in a forward rotation output state and sets the speed change operation member in the reverse operation range. When the vehicle is on, the forward/reverse operation member is operated so that the forward/reverse switching mechanism is in the reverse output state.

Preferably, the transmission structure may include a subtransmission mechanism capable of shifting HMT power operatively input from the output body to a plurality of gear stages including a low speed stage and a high speed stage.

According to the planetary gear assembly of the present invention, it is possible to reduce the size of the entire HMT device while expanding the speed change range of the HMT output in the HMT device formed in cooperation with the HST.
According to the HMT device according to the present invention, it is possible to reduce the size of the device while expanding the shift range of the HMT output.
According to the transmission structure according to the present invention, it is possible to increase the shift width of the HMT output, reduce the size of the HMT device, and improve the controllability of the HMT output.

FIG. 1 is a transmission schematic diagram of a transmission structure of a work vehicle to which a planetary gear assembly according to Embodiment 1 of the present invention is applied. FIG. 2 is a hydraulic circuit diagram of the transmission structure. FIG. 3 is a partial longitudinal sectional view of the HMT device including the planetary gear assembly according to the first embodiment. FIG. 4 is a longitudinal sectional view of the planetary gear assembly according to the first embodiment. FIG. 5 is an exploded longitudinal sectional view of a connecting member in the planetary gear assembly according to the first embodiment. FIG. 6 is a graph showing the relationship between the HST output and the HMT output in the HMT device including the planetary gear assembly according to the first embodiment. FIG. 7 is a graph showing the relationship between the HST output and the HMT output in a modified example of the HMT device including the planetary gear assembly according to the first embodiment. FIG. 8 is a transmission schematic diagram of a transmission structure of a working vehicle to which a planetary gear assembly according to Embodiment 2 of the present invention is applied. FIG. 9 is a graph showing the relationship between the HST output and the HMT output in the HMT device including the planetary gear assembly according to the second embodiment. FIG. 10 is a transmission schematic diagram of another transmission structure to which the planetary gear assembly according to the first embodiment is applied. 11 is a graph showing the relationship between the HST output and the output of the subtransmission mechanism in the transmission structure shown in FIG. 10. FIG. FIG. 12 is a transmission schematic diagram of a transmission structure of a work vehicle to which a planetary gear assembly according to Embodiment 4 of the present invention is applied. FIG. 13 is a partial transmission schematic diagram of a transmission structure of a working vehicle to which a planetary gear assembly according to Embodiment 5 of the present invention is applied.

Embodiment 1
An embodiment of a planetary gear assembly according to the present invention will be described below with reference to the accompanying drawings.
1 and 2 respectively show a transmission schematic diagram and a hydraulic circuit diagram of a transmission structure 200A in a working vehicle to which a planetary gear assembly 1A according to the present embodiment is applied.

As shown in FIG. 1, the work vehicle includes a drive source 410, main drive wheels 420, and the transmission structure 200A interposed in a traveling system transmission path from the drive source 410 to the main drive wheels 420. I have. 1 and 2 denotes a flywheel included in the driving source 410. As shown in FIG.

The planetary gear assembly 1A cooperates with a hydrostatic continuously variable transmission (HST) 110 that outputs the reference rotational speed power that is operatively input from the drive source 410 and outputs the HMT device (static). 100A, and is used as one component of the transmission structure 200A.

That is, as shown in FIG. 1, the transmission structure 200A comprises the HMT device 100A including the HST 110 and the planetary gear assembly 1A.

In the present embodiment, as shown in FIG. 1, the transmission structure 200A, in addition to the HMT device 100, further rotates the output (HMT output) of the HMT device 100A in forward and backward directions. A switchable forward/reverse switching mechanism 220 and a differential mechanism 230 differentially transmitting the output of the forward/reverse switching mechanism 220 to the pair of left and right main drive wheels 320 are provided.

The transmission structure 200A further includes a travel brake mechanism 240 that selectively applies a braking force to the pair of main drive wheels 320, a differential lock mechanism 235 that forcibly drives the pair of main drive wheels 320 synchronously, and the It also has a driving force extraction mechanism 250 for auxiliary driving wheels that can selectively output the output of the forward/reverse switching mechanism 220 to the auxiliary driving wheels.

Further, the transmission structure 200A includes a PTO shaft 260 for outputting rotational power to the outside, and a PTO multi-speed transmission mechanism 270 including a PTO clutch 265 interposed in a PTO transmission path from the drive source 410 to the PTO shaft 260. have.
The transmission structure 200A, the differential mechanism 230, the driving force take-out mechanism 250 for the auxiliary driving wheels, and the PTO multi-speed transmission mechanism 270 are housed in a transmission case (not shown).

The HST 110 is configured to continuously change the reference rotational speed power from the drive source 410 between the first HST speed and the second HST speed, and output the HST output after the speed change.

Specifically, as shown in FIGS. 1 and 2, the HST 10 is supported by a pump shaft 112 that receives a reference rotational speed power from the drive source 410 and the pump shaft 112 so as not to rotate relative to each other. a hydraulic motor 118 fluidly connected to the hydraulic pump 114 via a pair of hydraulic oil lines 115 and hydraulically rotationally driven by the hydraulic pump 114; It has a motor shaft 116 to support and an output adjusting member 120 to change the volume of at least one of the hydraulic pump 114 and the hydraulic motor 118 .

The output adjustment member 120 is actuated within an operable range defined by first and second actuating end positions, and the HST 10 controls the pump according to the operating position of the output adjustment member 120 within the operable range. The ratio of the rotation speed of the HST output from the motor shaft 116 to the reference rotation speed input to the shaft 112 (that is, the gear ratio of the HST 110) is steplessly changed between the first HST speed and the second HST speed. It is designed to be obtained.
In this embodiment, the output adjusting member 120 is configured to change the volumetric amount (discharge amount) of the hydraulic pump 114 .

In this embodiment, the HST 110 can switch the direction of rotation of the HST output between normal and reverse.

That is, in the HST 110, when the rotation direction of the reference rotation speed power is set to the first rotation direction (for example, forward rotation direction), the HST output when the output adjustment member 120 is positioned at the first operating end position is The rotational speed (first HST speed) is the maximum speed (-max) in a second rotational direction opposite to the first rotational direction (for example, reverse direction), and the output adjustment member 120 is at the second operating end position. The rotation speed (second HST speed) of the HST output when positioned at 2 is set to the maximum speed (+max) in the first rotation direction (for example, forward rotation direction).

In this case, when the output adjusting member 120 is positioned at the neutral position between the first and second operating end positions, the rotation speed of the HST output becomes neutral speed (zero speed).

The HST 110 can take a variety of forms, including axial and radial piston types.
When the HST 110 is of the axial piston type, the output adjusting member 120 can be a movable swash plate. When the HST 110 is of radial piston type, the output adjusting member 120 can be a movable cam ring.

The output adjustment member 120 can be actuated in response to human manipulation.
That is, as shown in FIG. 1, the transmission structure 200A includes a shift operation member 310 that can be manually operated within a shift operation range between the zero speed position and the maximum speed position, and the operation position of the shift operation member 310 is detected. an operating position sensor 315 for operating, an HST operating member 320 for operating the output adjusting member 120, and a control device 300 for controlling the operation of the HST operating member 320 according to the operating position of the shift operating member 310.
In the present embodiment, the shift operating member 310 is of a lever type.

As long as the HST operating member 320 can operate the output adjusting member 120 in response to a control signal from the control device 300, the hydraulic actuator includes a hydraulic servomechanism and an electromagnetic valve for switching the supply and discharge of pressure oil to the hydraulic servomechanism. It can take various forms such as an electric actuator.

FIG. 3 shows a partial longitudinal sectional view of the HMT device 100A including the planetary gear assembly 1A.
FIG. 4 shows a longitudinal sectional view of the planetary gear assembly 1A.

As shown in FIGS. 1 to 4, the planetary gear assembly 1A includes a transmission shaft 10 and first and second planetary gear mechanisms 20 and 30 supported by the transmission shaft 10. As shown in FIGS.

In the present embodiment, the transmission shaft 10 is operationally capable of receiving the HST output.
Specifically, the transmission shaft 10 operatively receives the HST output from the motor shaft 116 via the HST transmission gear train 130 .

The HST transmission gear train 130 has an HST drive gear 132 connected to the motor shaft 116 so as not to rotate relative to the axis, and an HST driven gear 134 operatively meshed with the HST drive gear 132 . .

As shown in FIGS. 1 and 3, the transmission shaft 10 is arranged parallel to the motor shaft 116, and is located on the first side in the axial direction (the side away from the motor shaft 116 in the axial direction). 3) supports the first planetary gear mechanism 20, and the second side in the axial direction (the side close to the motor shaft 116 in the axial direction, the left side in FIGS. 1 and 3) supports the first planetary gear mechanism 20. It supports two planetary gear mechanisms 30 .

The transmission shaft 10 supports the HST driven gear 134 on the second side in the axial direction from the portion that supports the second planetary gear mechanism 30 so as not to rotate relative to the axis.

The first planetary gear mechanism 20 includes, as shown in FIGS. 3 and 4, a first sun gear 22, a first planetary gear 24 meshing with the first sun gear 22, and a first interface gear meshing with the first planetary gear 24. A null gear 26 and a first carrier 28 that supports the first planetary gear 24 so as to be rotatable about its axis and rotates about the axis of the first sun gear 22 in conjunction with the revolution of the first planetary gear 24 about the first sun gear 22. , wherein the first sun gear 22, the first carrier 28 and the first internal gear 26 form a planetary triad.

As shown in FIGS. 3 and 4, the first sun gear 22, which is the first element of the three planetary elements, is supported by the transmission shaft 10 so as not to rotate relative to it.
As described above, the HST output is input to the transmission shaft 10 in this embodiment.
Therefore, in the present embodiment, the first sun gear 22 acts as a variable power input section for inputting the HST output.

The second element among the three planetary elements acts as a reference power input unit for inputting the reference rotational speed power.
In this embodiment, the first internal gear 26 is the second element of the first planetary gear mechanism 20 .

In this embodiment, the HMT device 100A is provided with a drive shaft 125 to which the reference rotational speed power is transmitted from the drive source 410, and the drive source 410 is connected to the first internal gear . The reference rotational speed power is operationally input from the drive shaft 125 to which the reference rotational speed power is operatively transmitted.

Specifically, in this embodiment, as shown in FIG. 3, the drive shaft 125 is coaxially connected to the pump shaft 112 so as not to rotate relative to the axis, and the HMT device 100A includes the the drive shaft 125, a first transmission gear train 135(1) capable of operatively transmitting the reference rotational speed power from the drive shaft 125 to the first internal gear 26, and the first transmission gear train 135(1) A first clutch mechanism 140(1) is provided to engage and disengage power transmission by means of the .

The first transmission gear train 135(1) is operatively meshed with the first drive gear 136(1) supported by the drive shaft 125 so as to be relatively rotatable about the axis. and the first driven gear 137 (1) supported directly or indirectly on the transmission shaft 10 so as to be relatively rotatable about the axis while being connected to the first internal gear 26 so as not to be relatively rotatable about the axis. have.

That is, in the present embodiment, the first internal gear 26 receives the reference rotational speed power from the drive shaft 125 via the first clutch mechanism 140(1) and the first transmission gear train 135(1). can be entered.

In the first planetary gear mechanism 20, the third element acts as a planetary output section that outputs combined rotational power obtained by synthesizing the rotational powers input to the first and second elements.
In this embodiment, the first carrier 28 is the third element.

The second planetary gear mechanism 30 includes, as shown in FIGS. A null gear 36 and a second carrier 38 that supports the second planetary gear 34 so as to be rotatable around the axis and rotates around the axis of the second sun gear 32 in conjunction with the revolution of the second planetary gear 34 around the second sun gear 32. , and the second sun gear 32, the second carrier 38 and the second internal gear 36 form a planetary triad.

As shown in FIGS. 3 and 4, the second sun gear 32, which is the first element of the three planetary elements, is supported by the transmission shaft 10 so as not to rotate relative to it.
As described above, the HST output is input to the transmission shaft 10 in this embodiment.
Therefore, in the present embodiment, the second sun gear 32 acts as a variable power input section for inputting the HST output.

The second element among the three planetary elements acts as a reference power input unit for inputting the reference rotational speed power.
In this embodiment, the second carrier 38 is the second element of the second planetary gear mechanism 30 .

In this embodiment, the second carrier 38 is adapted to receive the reference rotational speed power from the drive shaft 125 .

Specifically, in this embodiment, as shown in FIG. 3, the HMT device 100A includes a second transmission gear train capable of operatively transmitting the reference rotation speed power from the drive shaft 125 to the second carrier 38. 135(2) and a second clutch mechanism 140(2) for engaging and disengaging power transmission by the second transmission gear train 135(2).

The second transmission gear train 135(2) is operatively meshed with a second driving gear 136(2) supported by the driving shaft 125 so as to be relatively rotatable about the axis and the second driving gear 2136(2). and a second driven gear 137 (2) supported directly or indirectly on the transmission shaft 10 so as to be relatively rotatable about the axis while being connected to the second carrier 38 so as not to be relatively rotatable about the axis. ing.

That is, in the present embodiment, the second carrier 38 receives the reference rotational speed power from the drive shaft 125 via the second clutch mechanism 140(2) and the second transmission gear train 135(2). It is possible to

In the second planetary gear mechanism 30, the third element acts as a planetary output section that outputs combined rotational power obtained by synthesizing the rotational powers input to the first and second elements.
In this embodiment, the second internal gear 36 is the third element.

As shown in FIGS. 1 to 4, the planetary gear assembly 1A is further fitted around the transmission shaft 10 so as to be relatively rotatable about the axis, and is connected to the first and second planetary gear mechanisms 20 and 30. A connecting member 40 is provided for connecting the third elements to each other such that they cannot rotate relative to each other around the axis.

As mentioned above, in the present embodiment, the third element (first carrier 28) of the first planetary gear mechanism 20 acts as a combined output of the first planetary gear mechanism 20 and the second planetary gear mechanism. The third element (second internal gear 36) of the gear mechanism 30 acts as a combined output of said second planetary gear mechanism 30, so said connecting member 40 is connected to said first and second planetary gear mechanisms. Acts as a common HMT output member for both 20,30.

Specifically, as shown in FIGS. 3 and 4, the connecting member 40 is connected when the first planetary gear mechanism 20 is in the power transmission state and the second planetary gear mechanism 30 is in the power interruption state. outputs the synthesized rotational power (HMT output) by the first planetary gear mechanism 20, the first planetary gear mechanism 20 is in the power cutoff state, and the second planetary gear mechanism 30 is in the power transmission state. At that time, the combined rotational power (HMT output) by the second planetary gear mechanism 30 is output.

FIG. 5 shows an exploded longitudinal sectional view of the connecting member 40. As shown in FIG.
As shown in FIGS. 3 to 5, the connecting member 40 is fitted around the transmission shaft 10 so as to be relatively rotatable about the axis, and the first side in the axial direction serves as the third element of the first planetary gear mechanism 20. As shown in FIGS. and the second side in the axial direction is connected to the third element of the second planetary gear mechanism 30; there is

As described above, in this embodiment, the first carrier 28 acts as the third element (planetary output section) of the first planetary gear mechanism 20, and the second internal gear 36 serves as the second planetary gear. It acts as the third element (planetary output) of mechanism 30 .

Therefore, the connecting body 41 is fitted around the transmission shaft 10 so as to be relatively rotatable about the axis, the first side in the axial direction is connected to the first carrier 28 so as not to be relatively rotatable about the axis, and the second side in the axial direction is connected to the first carrier 28 . It is connected to the second internal gear 36 so as not to rotate relative to the axis.

More specifically, as shown in FIGS. 4 and 5, the coupling body 41 includes a cylindrical portion 42 extending in the axial direction and a first carrier 28 extending radially outward from the first side of the cylindrical portion 42 in the axial direction. and a second flange 44 extending radially outward from the axial second side of the cylindrical portion 42 and connected to the second internal gear 36 .

In this embodiment, the output body 45 is separate from the connecting body 41 .
Specifically, the output body 45 is arranged on the opposite side of the connecting body 41 in the axial direction across the first planetary gear 24 supported by the first carrier 28 and is located on the first side of the connecting body 41 in the axial direction. , a connecting flange 46 that is detachably connected to the shaft through a fastening member 49 such as a bolt, and a shaft portion 47 that extends from the connecting flange 46 to the first side in the axial direction.

As shown in FIG. 5, in this embodiment, the first carrier 28 has a first carrier pin 28a that supports the first planetary gear 24 so as to be rotatable about the axis.

The first carrier pin 28a is engaged with an engaging hole 46a formed in the connecting flange 46 on the first axial side and engaged in an engaging hole 43a formed on the first flange 43 on the second axial side. Engaged, the connecting flange 46 and the first flange 43 form a first carrier 28 that rotates about the axis of the first sun gear 22 with the first carrier pin 28a.

In the present embodiment, the output body 45 is detachably connected to the connecting body 41, but instead of this, the outer peripheral surface of the cylindrical portion 42 of the connecting body 41 is provided as an output body. It is also possible to provide a working output gear (not shown).

In this embodiment, as shown in FIG. 4, the first driven gear 137(1) is externally supported by the shaft portion 47 of the output body 45 so as to be relatively rotatable about the axis, and the input gear It is connected to the first drive gear 136(1) (see FIG. 3) at portion 137a(1) and to the first internal gear 26 at output gear portion 137b(1).

As shown in FIG. 4, in this embodiment, the second carrier 38 includes a second carrier pin 38a that supports the second planetary gear 34 so as to be rotatable around the axis, and the second sun gear 32 together with the second carrier pin 38a. and a second carrier body 38b supported by the transmission shaft 10 so as to be relatively rotatable about its axis so as to rotate about its axis.
The second driven gear 137(2) is supported by the second carrier body 38b so as not to rotate relative to the axis.

As shown in FIGS. 1 to 3, both the first and second clutch mechanisms 140(1) and 140(2) are supported by the drive shaft 125 in this embodiment.

That is, the first clutch mechanism 140(1) is provided on the drive shaft 125 so as to engage and disengage power transmission from the drive shaft 125 to the first drive gear 136(1). A mechanism 140(2) is mounted on the drive shaft 125 to engage and disengage power transmission from the drive shaft 125 to the second drive gear 136(2).

As shown in FIGS. 1 to 3, in this embodiment, the first and second clutch mechanisms 140(1) and 140(2) are hydraulic multi-plate clutches.

Specifically, the first clutch mechanism 140(1) includes a first clutch housing 141(1) supported by the drive shaft 125 so as not to relatively rotate, and a first clutch housing 141(1) supported by the first clutch housing 141 so as not to relatively rotate. A first friction plate group 142 including a first driving side friction plate and a first driven side friction plate supported by the first driving gear 136(1) so as to face the first driving side friction plate so as not to rotate relative to the first driving side friction plate. (1) and a first piston 143(1) that frictionally engages the first friction plate group 142(1).

The second clutch mechanism 140(2) includes a second clutch housing 62 supported non-rotatably on the drive shaft, a second drive-side friction plate non-rotatably supported on the second clutch housing 62, a second friction plate group 142(2) including a second driven side friction plate supported by the second drive gear 136(2) so as to face the second drive side friction plate so as not to rotate relative to the second drive side friction plate; It has a second piston 143(2) that frictionally engages the second friction plate group 142(2).
As shown in FIG. 3, the first and second clutch housings 141(1) and 141(2) are integrally formed.

As shown in FIG. 3, in the present embodiment, the first and second clutch mechanisms 140(1), 140(2) are arranged so that the first and second flanges 43 of the coupling body 41 are arranged in the axial direction. , 44, and portions of the first and second clutch mechanisms 140(1), 140(2) are disposed between the outer peripheral surface of the tubular portion 42 and the first and second flanges 43, 44. and the space S (see FIG. 4) defined by the facing surface of the .

According to such a configuration, the drive shaft 125, the first and second clutch mechanisms 140(1), 140(2), the first and second transmission gear trains 135(1), 135(2), and , the size of the structure including the planetary gear assembly 1A can be reduced.

The first and second clutch mechanisms 140(1), 140(2) are powered by first and second clutch actuating members 145(1), 145(2), respectively, actuated and controlled by the controller 300. is configured to engage and disengage.

That is, the transmission structure 200A further includes the first clutch operating member 145(1) for switching the engagement/disengagement operation of the first clutch mechanism 140(1), and the engagement/disengagement of the second clutch mechanism 140(2). The second clutch actuating member 145(2) for switching operation is provided, and the control device 300, in addition to controlling the operation of the HST actuating member 320, controls the first and second clutch actuating members 145(1), 145(2).

In this embodiment, the first and second clutch actuating members 145(1), 145(2) are hydraulic actuators.

Specifically, as shown in FIG. 2, the first clutch actuation member 145(1) includes a pressurized oil supply line 146 whose upstream side is fluidly connected to a hydraulic source 430 such as a hydraulic pump, a drain line 147, and the first clutch actuating member 145(1). A first supply/discharge line 148(1) for supplying and discharging pressure oil to/from the one clutch mechanism 140(1) and a first clutch electromagnetic valve 150(1) are provided.

The first clutch electromagnetic valve 150 ( 1 ) is set to a clutch engagement position and a clutch engagement position for fluidly connecting the first supply/discharge line 148 ( 1 ) to the pressure oil supply line 146 in response to a signal from the control device 300 . It is configured to selectively assume a de-clutching position fluidly connecting said first supply and drain line 148 ( 1 ) to said drain line 147 .

The second clutch actuating member 145(2) includes a pressure oil supply line 146, a drain line 147, and a second supply/discharge line 148 for supplying/discharging pressure oil to/from the second clutch mechanism 140(2). (2) and a second clutch solenoid valve 150(2).

The second clutch electromagnetic valve 150 ( 2 ) is set to a clutch engagement position and a clutch engagement position for fluidly connecting the second supply/discharge line 148 ( 2 ) to the pressure oil supply line 146 in response to a signal from the control device 300 . It is configured to selectively assume a clutch disengaged position that fluidly connects the second supply and drain line 148 ( 2 ) to the drain line 147 .

Reference numeral 146a in FIG. 2 denotes a working oil relief valve for setting the clutch working oil pressure of the pressure oil supply line 146. As shown in FIG.

In the present embodiment, the first and second clutch solenoid valves 150(1) and 150(2) are proportional pressure valves, but they may be ON/OFF valves instead. is.

In the present embodiment, the first and second clutch operating members 145(1) and 145(2) are hydraulic actuators for operating hydraulic multi-plate clutches. When the two-clutch mechanisms 140(1) and 140(2) are dog clutches, the first and second clutch actuating members 145(1) and 145(2) are driven by an electric motor or the like for shifting the dog clutches. Electric actuators are also possible.

As described above, the transmission structure 200A has the forward/reverse switching mechanism 220 in the present embodiment.
In this case, the transmission structure 200A is further provided with a forward/reverse operation member 155 that operates the forward/reverse switching mechanism 220, and the shift operation member 310 is configured to move from the zero speed position to the forward maximum speed position. Manual operation is possible in the operation range and the reverse side operation range from the zero speed position to the reverse side maximum speed position.

When the gear shift operation member 310 is positioned in the forward operation range, the control device 300 puts the forward/reverse switching mechanism 220 into a forward rotation output state (forward rotation output state) and shifts the gear shift operation member 310 forward. is positioned in the reverse operation range, the forward/reverse operation member 155 is operated so that the forward/reverse switching mechanism 220 is in the reverse output state (reverse output state).

The transmission structure 200A may be provided with a dedicated forward/reverse switching operation member for manually operating the forward/reverse switching mechanism 220. FIG. In this case, the forward/reverse switching operation member can have various configurations such as a lever mechanically operably connected to the forward/reverse switching mechanism 220 or an electric switch type.
When the forward/reverse switching operation member is provided, the speed change operation member 310 is, for example, a pedal type member that can be operated from a zero speed position to a maximum speed position, and the transmission structure 200A is configured to operate the speed change operation. It is configured to output driving force from zero speed to maximum forward speed and from zero speed to maximum reverse speed in response to manual operation of member 310 and the forward/reverse switching operation member.

The forward/reverse movement operating member 155 can take various forms such as a hydraulic actuator and an electric actuator as long as it can operate the forward/reverse movement switching mechanism 220 in response to a control signal from the control device 300 .

In this embodiment, as shown in FIG. 2, the forward/backward movement operating member 155 is also a hydraulic actuator.

As shown in FIG. 1, the forward/reverse switching mechanism 220 is arranged between an intermediate drive shaft 210 that operatively receives the HMT output from the connecting member 40 and a traveling output shaft 215 that is operatively connected to the differential mechanism 230. , to switch the direction of rotation of the HMT output between the forward direction and the reverse direction.

In the present embodiment, the forward/reverse switching mechanism 220 is supported by the forward drive gear 331F supported by the intermediate drive shaft 210 and the travel output shaft 215, and is engaged with the forward drive gear 331F. A forward gear train 330F including a side driven gear 332F, a reverse drive gear 331R supported by the intermediate drive shaft 210, and supported by the travel output shaft 215, and connected to the reverse drive gear 331R via an idle gear 333. A reverse gear train 330R including an engaged reverse driven gear 332R, a forward clutch mechanism 340F that engages and disengages power transmission of the forward gear train 330F, and a reverse gear train that engages and disengages power transmission of the reverse gear train 330R. and a clutch mechanism 340R.

As shown in FIG. 2, the forward/reverse operation member 155 includes the pressure oil supply line 146, the drain line 147, and a forward supply/discharge line 156F for supplying/discharging pressure oil to/from the forward clutch mechanism 330F. , a reverse supply/discharge line 156R for supplying and discharging pressurized oil to and from the reverse clutch mechanism 330R, a forward electromagnetic valve 157F, and a reverse electromagnetic valve 158R.

In response to a signal from the control device 300, the forward solenoid valve 157F is moved to a clutch engagement position where the forward supply/discharge line 156F is fluidly connected to the pressure oil supply line 146 and to a position where the forward supply/discharge line 156F is connected to the drain. It is configured to selectively assume a declutching position fluidly connected to line 147 .

Similarly, the reverse solenoid valve 157R is, in response to a signal from the control device 300, a clutch engagement position where the reverse supply/discharge line 156R is fluidly connected to the pressure oil supply line 146, and the reverse supply/discharge line 156R. to the drain line 147 to selectively assume a declutching position.

In this embodiment, the transmission structure 200A is provided with a lubricating oil supply structure.
As shown in FIGS. 2 to 4, the lubricating oil supply structure includes a lubricating oil supply line 161 for receiving discharged oil after pressure regulation from the hydraulic oil relief valve 146a, and oil received from the lubricating oil supply line 161. through an axial oil passage formed in the intermediate drive shaft 210 (not shown in FIGS. 2 to 4) and through an axial oil passage 162a (see FIG. 4) formed in the transmission shaft 10. The lubricating oil line 162 for planetary gears that guides the lubricating oil received from the lubricating oil line 162 and the lubricating oil supply line 161 to the desired lubrication points of the first and second planetary gear mechanisms 20 and 30 through the axis line formed on the drive shaft 125. It also has a clutch lubricating oil line 163 that guides it to desired lubricating points of the first and second clutch mechanisms 140(1) and 140(2) through an oil passage 163a (see FIG. 3).

Reference numeral 161a in FIG. 2 denotes a lubricating oil relief valve for setting the hydraulic pressure of the lubricating oil supply line 161. As shown in FIG.

Here, the set gear ratios of the first and second planetary gear mechanisms 20 and 30 will be described.
FIG. 6 shows a graph representing the relationship between the HST output and the HMT output in the HMT device 100A.

As shown in FIG. 6 , the first planetary gear mechanism 20 is in a first planetary transmission state (second 1st gear transmission state), when the HST output is set to the HST speed for zero speed, the HMT output appearing at the first carrier 28 (that is, the connecting member 40) becomes zero speed, and the HST output becomes the first HST. The HMT output appearing on the first carrier 28 rotates at an accelerated speed in the first rotation direction, which is one side of the axis, and the HST output rotates at a predetermined speed. The gear ratio is set so that the HMT output appearing at the first carrier 28 rotates in the first rotational direction at the predetermined first speed maximum speed when the HST speed for the first speed maximum speed is selected. there is

In the present embodiment, the HST speed for zero speed is a speed shifted from the first HST speed, which is one end of the variable range of the HST output, to the second HST speed by a predetermined speed.

This is due to the following reasons.
That is, theoretically, it is possible to set the HST speed for zero speed to the first HST speed. Even if it is positioned at the first operating end position, a situation may arise in which the HST output does not reach the first HST speed.
In consideration of this point, the control device 300 sets the HST speed for zero speed to a speed shifted from the first HST speed, which is one speed end of the variable range of the HST output, toward the second HST speed by a predetermined speed. are doing.

For the same reason, in the present embodiment, the control device 300 shifts the speed from the second HST speed, which is the speed end on the other side of the variable range of the HST output, to the first HST speed by a predetermined speed. It is set to the HST speed for the first speed stage maximum speed.
That is, in the present embodiment, the "maximum HST speed" refers to an output value adjusted by the control device 300 rather than a mechanical limit output value of the HST 110. FIG.

As shown in FIG. 6, the second planetary gear mechanism 30 is in a second planetary transmission state (second speed) in which the HST output is input to the second sun gear 32 and the reference rotation speed power is input to the second carrier 38 . gear transmission state), when the HST output is set to the HST speed for the first speed highest speed, the HMT output appearing at the second internal gear 36 (that is, the connecting member 40) is the first speed highest speed. As the speed increases and the HST output changes from the second HST speed side to the first HST speed side, the HMT output appearing at the second internal gear 36 accelerates rotation in the first rotation direction, which is one side around the axis. In addition, when the HST output is set to the predetermined HST speed for the second speed stage maximum speed, the HMT output appearing at the second internal gear 36 moves in the first rotation direction to the predetermined second speed stage maximum speed. The gear ratio is set so that it rotates at

In the present embodiment, the HST speed for the highest speed of the second speed stage is also a speed shifted from the first HST speed, which is one end of the variable range of the HST output, toward the second HST speed by a predetermined speed. .

If the maximum vehicle speed that can be output in the second planetary transmission state (second gear transmission state) is too fast for the specifications of the work vehicle, the control device 300 is adjusted to: A speed greatly shifted from the first HST speed to the second HST speed side (preferably to the neutral position N or the vicinity of the neutral position) can be set as the HST speed for the highest speed of the second speed stage.

In this embodiment, the control device 300 is configured to produce the HMT output shown in FIG. 6 by performing the following control.

That is, the transmission structure 200A is further provided with an output sensor 50 (see FIG. 1) that directly or indirectly detects the rotational speed of the connecting member 40. As shown in FIG.
The output sensor 50 is arranged, for example, to detect the rotational speed of the coupling member 40 or the intermediate drive shaft 210 .

As shown in FIG. 6, the shift operating range of the shift operating member 310 is divided into a first gear operating area on the low speed side and a second gear operating area on the higher speed side than the first gear operating area. .
The first speed stage operation area is set in a range from the zero speed position to the first speed stage maximum speed position, and the second speed stage operation area is set from the first speed stage maximum speed position to the second speed stage maximum speed position. Set to range to position.

The control device 300 executes the following operation control for the first and second clutch operating members 145(1), 145(2).

That is, the control device 300
When it is determined based on the signal from the operation position sensor 315 that the shift operation member 310 is being operated in the first speed stage operation area, the first clutch mechanism 140(1) is in the engaged state and the second operating the first and second clutch operating members 145(1) and 145(2) so that the clutch mechanism 140(2) is in the disengaged state;
・When it is determined that the shift operation member 310 is positioned at the first speed maximum speed position based on the signal from the operation position sensor 315, the first and second clutch mechanisms 140(1), 140(2) are operated. operate the first and second clutch actuating members 145(1) and 145(2) so that one of them is engaged and the other is disengaged;
When it is determined based on the signal from the operation position sensor 315 that the gear shift operation member 310 is being operated in the second speed stage operation area, the first clutch mechanism 140(1) is in the disengaged state and the second clutch is disengaged. The first and second clutch actuating members 145(1), 145(2) are actuated so that the mechanism 140(2) is engaged.

Further, the control device 300 executes the following operation control for the HST operation member 320. As shown in FIG.

That is, the control device 330
When it is determined that the shift operation member 310 is operated to the zero speed position based on the signal from the operation position sensor 315, the HST operation member 320 is operated so that the HST output becomes the HST speed for zero speed,
When it is determined based on the signal from the operation position sensor 315 that the speed change operation member 310 is being operated to increase speed within the first gear operation area, the HST output shifts from the first HST speed side to the second HST speed side. actuating the HST actuating member 320 to shift gears;
When it is determined based on the signal from the operation position sensor 315 that the shift operation member 310 has been operated to the first speed highest speed position, the HST is adjusted so that the HST output becomes the first speed highest speed HST speed. actuating the actuating member 320;
When it is determined based on the signal from the operation position sensor 315 that the speed change operation member 310 is being operated to increase speed within the second speed stage operation area, the HST output is shifted from the second HST speed side to the first HST speed side. actuating the HST actuating member 320 to shift gears;
When it is determined that the shift operating member 310 has been operated to the highest speed position based on the signal from the operating position sensor 315, the HST operating member 320 is operated so that the HST output becomes the HST speed for the highest speed of the second speed stage. Let

Furthermore, the control device 300 executes the following operation control for the forward/backward movement operating member 155 .

That is, the control device 300
When it is determined based on the signal from the operation position sensor 315 that the speed change operation member 310 is positioned in the forward operation range, the forward/reverse operation member is adjusted so that the forward/reverse switching mechanism 220 is in the normal rotation output state. 155 is activated;
When it is determined based on the signal from the operation position sensor 315 that the speed change operation member 310 is positioned in the reverse operation range, the forward/reverse operation member 155 is adjusted so that the forward/reverse switching mechanism 220 is in the reverse output state. to activate.

Embodiment 2
Another embodiment of a planetary gear assembly according to the present invention will be described below with reference to the accompanying drawings.
FIG. 8 shows a transmission schematic diagram of a transmission structure 200B for a work vehicle to which the planetary gear assembly 2 according to the present embodiment is applied.
In the drawings, the same members as in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted as appropriate.

As shown in FIG. 8, the planetary gear assembly 1B according to the present embodiment further has an input member 60 compared to the planetary gear assembly 1 according to the first embodiment.

The input member 60 is a second element (a second carrier 36 in the illustrated embodiment) for inputting a reference rotational speed power of the second planetary gear mechanism 30 in a state in which the input member 60 is rotatable relative to the transmission shaft 10 about the axis. ), and further has first and second input gear portions 61 and 62 capable of inputting the reference rotational speed power.
The pitch diameter of the second input gear portion 62 is smaller than the pitch diameter of the first input gear portion 61 .

The HMT device 100B formed by the planetary gear assembly 1B cooperating with the HST 10 further provides the reference rotational speed power from the drive shaft 125 to the second planetary gear mechanism 30 as compared with the HMT device 100A. A third transmission gear train 135(3) capable of operatively transmitting two elements (the second carrier 38), and a third clutch mechanism 140(3) for engaging and disengaging power transmission by the third transmission gear train 135(3). ) and

The gear ratio of the third transmission gear train 135(3) is set so as to rotate the second carrier 38 at a higher speed than the second transmission gear train 135(2).

In the present embodiment, the third transmission gear train 135(3) includes a third drive gear 136(3) supported by the drive shaft 125 so as to be relatively rotatable about the axis, and a third drive gear 136(3). 3), the third driven gear 137 is supported directly or indirectly on the transmission shaft 10 so as to be rotatable relative to the axis while being operatively meshed with the second carrier 38 and connected to the second carrier 38 so as not to be relatively rotatable about the axis. (3).

The first and second input gear portions 61 and 62 of the input member 60 act as the second driven gear 137(2) and the third driven gear 137(3), respectively.

The third clutch mechanism 140 ( 3 ) is configured to engage and disengage power transmission by a third clutch operating member (not shown) whose operation is controlled by the control device 300 .

FIG. 9 shows a graph representing the relationship between the HST output and the HMT output in the HMT device 100B.

As shown in FIG. 9, in the HMT device 100B, the second planetary transmission state includes a second gear transmission state and a third gear transmission state.

The second gear transmission state is achieved by disengaging the first clutch mechanism 140(1), engaging the second clutch mechanism 140(2), and disengaging the third clutch mechanism 140(3). This is the transmission state that appears.

The third gear transmission state is achieved by disengaging the first clutch mechanism 140(1), disengaging the second clutch mechanism 140(2), and engaging the third clutch mechanism 140(3). This is the transmission state that appears.

In this case, the shift operation range of the shift operation member 310 is, as shown in FIG. It includes a second speed operation region up to the second speed highest speed position and a third speed speed operation region from the second speed highest speed position to the third speed highest speed position.

The control device 300 controls the HST operating member 320 and the first and second clutch operating members when the shift operating member 310 is operated in the range from the zero speed position to the second speed maximum speed position. 145(1) and 145(2) are controlled in the same manner as in the first embodiment.

On the other hand, when the gear shift operation member 310 is positioned in the third gear stage operation region, the control device 300 disengages the first and second clutch mechanisms 140(1) and 140(2) and The first to third clutch actuating members are actuated so that the third clutch mechanism 140(3) is in the engaged state, thereby creating the third gear transmission state.

In the present embodiment, the control device 300 performs the following operation to prevent a rapid speed change in the HMT output when shifting between the second speed transmission state and the third speed transmission state. Execute control.

That is, the control device 300 changes the HST output to the HST speed for the second speed stage maximum speed when the speed change operation member 310 is accelerated to the second speed stage maximum speed position within the second speed stage operation region. The HST actuating member 320 is operated so that the HMT output is set to the second speed stage maximum speed.

Here, in the third speed transmission state, the second element (the second carrier 38 in the illustrated embodiment) of the second planetary gear mechanism 30 has a gear ratio higher than that of the second transmission gear train 135 (2). Reference rotation speed power is input through the third transmission gear train 135(3).

Therefore, if the HST output is maintained at the HST speed for the highest speed of the second speed stage and the transmission state is shifted from the second speed transmission state to the third speed transmission state, the HMT output undergoes a large change in speed.

In consideration of this point, in the present embodiment, when the shift operation member 310 is operated from the second speed operation region to the third speed operation region, the control device 300 controls the second clutch mechanism 140(2) is in the disengaged state and the third clutch mechanism 140(3) is in the engaged state, the second and third clutch actuating members are operated to shift from the second gear transmission state to the third gear. While shifting to the transmission state, the HST operating member 320 is operated so that the HST output shifts from the HST speed for the highest speed of the second speed stage to the HST speed for the lowest speed of the third speed stage. It prevents or reduces speed changes in the HMT output when transitioning between states and third gear transmission states.

The HST speed for the 3rd speed stage lowest speed is set to a speed at which the HMT output becomes the 2nd speed stage maximum speed under the 3rd speed stage transmission state.

Embodiment 3
In this embodiment, the planetary gear assembly 1A according to the first embodiment is applied to a transmission structure 200C different from the transmission structure 200A.
FIG. 10 shows a transmission schematic diagram of a transmission structure 200C in a work vehicle to which the planetary gear assembly 1A is applied.
In the drawings, the same members as in Embodiments 1 and 2 are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

As shown in FIG. 10, the transmission structure 200C includes an auxiliary transmission mechanism 280 capable of multi-shifting the output of the HMT device 100A, unlike the transmission structure 200A in the first embodiment.

In the present embodiment, the auxiliary transmission mechanism 280 is disposed between the HMT device 100A and the forward/reverse switching mechanism 220 with respect to the power transmission direction, and has two stages of low speed L and high speed H. It is possible to shift to

The subtransmission mechanism 280 operates, for example, in response to a manual operation of a subtransmission operating member (not shown) composed of a lever or the like or an electric switch, via a mechanical link mechanism, or via the control device 300. The low gear L and the high gear H are switched via a sub-transmission actuating member such as a hydraulic actuator or an electric actuator whose operation is controlled by.

FIG. 11 shows a graph representing the relationship between the HST output and the output of the auxiliary transmission mechanism.

The transmission structure 200</b>C is provided with an auxiliary transmission sensor 285 capable of detecting the transmission state of the auxiliary transmission mechanism 280 and transmitting a detection signal to the control device 300 .
The sub-transmission sensor 285 may be a sensor that detects the operating position of the sub-transmission operation member, a sensor that detects the operating state of the sub-transmission mechanism 280, or a sensor that detects the movement of the sub-transmission operation member. can take the form

In the present embodiment, as shown in FIG. 11, the control device 300 outputs the HST in response to the operation of the shift operation member 310 to the second speed maximum speed position in the sub-shift L speed engagement state. is set as the HST speed for the second speed stage maximum speed when the sub-shift L stage is engaged, while in the sub-shift H stage engagement state, according to the operation of the shift operation member 310 to the second speed stage maximum speed position The HST output is configured to be the HST speed for the second speed stage maximum speed when the sub-shift H stage is engaged which is lower than the HST speed for the second stage maximum speed when the sub-shift L stage is engaged by a predetermined speed. .

The HST speed for the second speed stage maximum speed when the sub-shift L stage is engaged and the HST speed for the second speed stage maximum speed when the sub-shift H stage is engaged are appropriately set according to the specifications of the work vehicle.

Embodiment 4
Hereinafter, still another embodiment of the planetary gear assembly according to the present invention will be described with reference to the attached drawings.
FIG. 12 shows a partial transmission schematic diagram of a transmission structure 200D in a work vehicle to which the planetary gear assembly 1D according to the present embodiment is applied.
In the drawings, the same members as in Embodiments 1 to 3 are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

As shown in FIG. 12, the planetary gear assembly 1D includes a connecting member 70 instead of the connecting member 40, unlike the planetary gear assembly 1A according to the first embodiment.

That is, the planetary gear assembly 1</b>D includes the transmission shaft 10 , the first and second planetary gear mechanisms 20 and 30 , and the connecting member 70 .

The planetary gear assembly 1D according to the present embodiment is
A reference rotational speed power input section in which the first sun gear 22 is supported by the transmission shaft 10 so as not to be relatively rotatable about the axis, and one of the first carrier 28 and the first internal gear 26 is capable of inputting the reference rotational speed power. a point that acts as
- The second sun gear 32 is supported by the transmission shaft 10 so as not to rotate relative to the axis, and acts as a reference rotational speed power input part of the first planetary gear mechanism 20, which is among the second carrier 38 and the second internal gear 36. A planetary element different from the planetary element acting as a reference rotational speed power input section capable of inputting reference rotational speed power;
The connecting member 70 includes a planetary element other than the first sun gear 22 of the first planetary gear mechanism 20 and a planetary element acting as a reference rotation speed power input section, and a second sun gear of the second planetary gear mechanism 30. 32 and a planetary element other than the planetary element acting as the reference rotational speed power input section are connected so as not to rotate relative to each other about the axis, which is common to the planetary gear assembly 1A according to the first embodiment.

That is, in the planetary gear assembly 1A according to the first embodiment, the first sun gear 22 is supported by the transmission shaft 10 so as not to be relatively rotatable about the axis, and is one of the first carrier 28 and the first internal gear 26. The first internal gear 26 acts as a reference rotation speed power input section, the second sun gear 32 is supported by the transmission shaft 10 so as not to rotate relative to the axis, and the second carrier 38 and the second internal gear 36, A planetary element (second carrier 38) different from the planetary element (first internal gear 26) acting as a reference rotation speed power input portion in the first planetary gear mechanism 20 acts as a reference rotation speed power input portion, The connecting member 40 includes a planetary element (first carrier 28) other than the first sun gear 22 and the planetary element (first internal gear 26) that acts as a reference rotation speed power input part of the first planetary gear mechanism 20, In the second planetary gear mechanism 30, the planetary elements (second internal gear 36) other than the second sun gear 32 and the planetary elements (second carrier 38) acting as the reference rotational speed power input section are not relatively rotatable about the axis. is connected to

In the planetary gear assembly 1D according to the present embodiment, the first sun gear 22 is supported by the transmission shaft 10 so as not to be relatively rotatable about the axis. 1 carrier 28 acts as a reference rotational speed power input portion, second sun gear 32 is supported by transmission shaft 10 so as not to rotate relative to its axis, and out of second carrier 38 and second internal gear 36, first A planetary element (second internal gear 36), which is different from the planetary element (first carrier 28) acting as a reference rotation speed power input portion in the planetary gear mechanism 20, acts as a reference rotation speed power input portion, and the connecting member 70 is a planetary element (first internal gear 26) other than the first sun gear 22 and a planetary element (first carrier 28) acting as a reference rotational speed power input portion of the first planetary gear mechanism 20, and the second In the planetary gear mechanism 30, the planetary elements (second carrier 38) other than the second sun gear 32 and the planetary elements (second internal gear 36) acting as the reference rotation speed power input section are connected so as not to be relatively rotatable about the axis. ing.

On the other hand, in the planetary gear assembly 1A according to the first embodiment, the connecting member 40 functions as the HMT output member, whereas in the planetary gear assembly 1D according to the present embodiment, the transmission shaft 10 Acts as the HMT output member, the planetary gear assembly 1D according to the present embodiment differs from the planetary gear assembly 1A according to the first embodiment.

Specifically, in the planetary gear assembly 1D, the first carrier 28 receives the reference rotational speed power from the drive shaft 125 via the first transmission gear train 135(1), and the second internal gear 36 inputs the reference rotational speed power from the drive shaft 125 through the second transmission gear train 135(2).

The connecting member 70 connects the first internal gear 26 and the second carrier 38 in a state in which the connecting member 70 is fitted around the transmission shaft 10 so as to be relatively rotatable about the axis, and furthermore, the HST output is operatively input. It is possible.

That is, in this embodiment, the first internal gear 26 acts as a variable power input portion for inputting the HST output in the first planetary gear mechanism 20, and the second carrier 38 acts as the second planetary gear mechanism. Acts as a variable power input at 30 to input the HST output.

In this embodiment, the connecting member 70 receives the HST output from the motor shaft 116 via the HST transmission gear train 130 .

Thus, in the first planetary gear mechanism 20, the first carrier 28 receives the reference rotation speed power and the first internal gear 26 receives the HST output, so that the transmission shaft 10 rotates relative to the axis. The impossibly supported first sun gear 22 acts as a planetary output for outputting the combined rotational power.

In the second planetary gear mechanism 30, the second internal gear 36 receives the reference rotation speed power and the second carrier 38 receives the HST output, so that the transmission shaft 10 cannot rotate relative to the axis. The supported second sun gear 32 acts as a planetary output section that outputs combined rotational power.

The transmission shaft 10 can output its own rotational power to the outside, and acts as a common HMT output member for both the first and second planetary gear mechanisms 20 and 30 .

Embodiment 5
Hereinafter, still another embodiment of the planetary gear assembly according to the present invention will be described with reference to the attached drawings.
FIG. 13 shows a partial transmission schematic diagram of a transmission structure 200E in a work vehicle to which the planetary gear assembly 1E according to the present embodiment is applied.
In the drawings, the same members as those in Embodiments 1 to 4 are denoted by the same reference numerals, and description thereof will be omitted as appropriate.

The planetary gear assembly 1E according to the present embodiment has a cylindrical transmission shaft 15 instead of the transmission shaft 10, a connection member 80 instead of the connection member 40, and , and an output shaft 90, which is different from the planetary gear assembly 1A according to the first embodiment.

Both ends of the output shaft 90 are bearing-supported by supporting walls of a transmission case (not shown), and one end is provided with a joint portion for coupling with the above-described intermediate drive shaft 210 .

The transmission shaft 15 is externally supported by the output shaft 90 so as to be relatively rotatable about its axis, and can receive an HST output from the motor shaft via the HST transmission gear train 130 .

The connecting member 80 includes planetary elements other than the first sun gear 22 of the first planetary gear mechanism 20 and the planetary elements forming the reference rotation speed power input section, and the second sun gear 32 of the second planetary gear mechanism 30 . and a connecting body 81 for connecting the planetary elements other than the planetary elements forming the reference rotation speed power input section.

As shown in FIG. 13, in the present embodiment, the first internal gear 26 acts as a reference rotation speed power input portion of the first planetary gear mechanism 20, and the second carrier 38 acts as the second planetary gear mechanism. 30 acts as a reference rotational speed power input section.
Therefore, the connecting body 81 connects the first carrier 28 and the second internal gear 36 so that they cannot rotate relative to each other about the axis.

As shown in FIG. 13, the connecting member 80 further includes an output body 85 capable of outputting the rotational power of the connecting body 81 to the outside.
In the present embodiment, the output body 85 is coaxially connected to the output shaft 90 so as not to be relatively rotatable around the axis.

As shown in FIG. 13, the HMT device 100E provided with the planetary gear assembly 1E has, in comparison with the HMT device 100A, instead of the first and second clutch mechanisms 140(1) and 140(2), First and second clutch mechanisms 180(1), 180(2) are provided.

The first and second drive gears 136(1) and 136(2) are connected to the drive shaft 125 connected to the pump shaft 112 so as not to rotate relative to each other around the axis, and the first and second clutches Mechanisms 180 ( 1 ) and 180 ( 2 ) are arranged coaxially with the transmission shaft 15 .

Specifically, the first clutch mechanism 180(1) connects the first driven gear 137(1) to the reference rotation speed power input portion (the first internal in this embodiment) of the first planetary gear mechanism 20. It is configured to engage and disengage power transmission to the gear 26).

The second clutch mechanism 180(2) is designed to transfer power from the second driven gear 137(2) to the reference rotation speed power input portion (the second carrier 36 in the present embodiment) of the second planetary gear mechanism 30. It is configured to engage and disengage the power transmission.

In the first embodiment (FIG. 1), the first clutch mechanism 140(1) is arranged between the drive shaft 125 and the first drive gear 136(1), and the second clutch mechanism 140(2) is arranged between the drive shaft 125 and the first drive gear 136(1). ) is arranged between the drive shaft 125 and the second drive gear 136(2), when one clutch mechanism (for example, the first clutch mechanism 140(1)) is engaged, The drive gear on the non-engagement side (in this example, the second drive gear 136(2)) is a driven gear (in this example, the second driven gear 137(2)) that receives the rotation of the connecting member 40. ) will be back-driven. At this time, if the difference in relative rotation between the drive gear on the non-engagement side (in this example, the second drive gear 136(2)) and the drive shaft 125 exceeds the allowable value, abnormal wear or Burn-in may occur.

On the other hand, in the present embodiment (FIG. 13), the first and second drive gears 136(1) and 136(2) are in a state in which they cannot rotate relative to the drive shaft 125 around the axis. A first clutch mechanism 180(1) is disposed between the transmission shaft 15 and the first driven gear 137(1), and a second clutch mechanism 180(2) is disposed between the transmission shaft 15 and the second driven gear 137(1). (2). Therefore, when one of the clutch mechanisms (for example, the first clutch mechanism 140 (1)) is engaged, the non-engaging side driven gear (in this example, the second driven gear 137 (2) ) has the advantage that the rotation of the connecting member 80 is not transmitted and the design around the drive shaft 125 can be advantageous.

1A to 1E planetary gear assemblies 10, 15 transmission shaft 20 first planetary gear mechanism 22 first sun gear 26 first internal gear 28 first carrier 30 second planetary gear mechanism 32 second sun gear 36 second internal gear 38 second Carriers 40, 70, 80 Connecting members 41, 81 Connecting body 42 Cylindrical part 43 First flange 44 Second flanges 45, 85 Output body 46 Connecting flange 47 Shaft part 50 Output sensor 60 Input member 61 First input gear part 62 Second Input gear portion 85 Output shafts 100A to 100E HMT device 110 HST
112 pump shaft 116 motor shafts 100A to 100D HMT device 125 drive shaft 134 HST driven gear 135 (1) first transmission gear train 136 (1) first drive gear 137 (1) first driven gear (transmission gear member)
137a (1) Input gear portion 137b (1) Output gear portion 135 (2) Second transmission gear train 136 (2) Second drive gear 137 (2) Second driven gear 135 (3) Third transmission gear train 136 ( 3) Third driving gear 137(3) Third driven gear 140(1), 180(1) First clutch mechanism 140(2), 180(2) Second clutch mechanism 140(3) Third clutch mechanism 200A- 200E Transmission structure 220 Forward/reverse switching mechanism 280 Auxiliary transmission mechanism 300 Control device 310 Shift operation member 315 Operation position sensor 320 HST operation member 410 Drive source

Claims (28)

A reference rotational speed power operatively input to the pump shaft from a drive source is steplessly changed between the first HST speed and the second HST speed, and the HMT outputs the HST output after the speed change from the motor shaft in cooperation with the HST. A planetary gear assembly forming a device comprising:
a transmission shaft;
It has three planetary elements including a first sun gear, a first carrier, and a first internal gear, wherein the first sun gear is supported by the transmission shaft so as not to rotate relative to the axis, and the first carrier and the first internal gear. a first planetary gear mechanism that forms a reference rotational speed power input section in which one of the gears is capable of inputting the reference rotational speed power;
planetary three elements including a second sun gear, a second carrier and a second internal gear, the second sun gear being supported by the transmission shaft so as not to rotate relative to the axis, the second carrier and the second internal gear; Among the gears, a second planetary element forming a reference rotational speed power input section to which a planetary element different from the planetary element forming the reference rotational speed power input section in the first planetary gear mechanism is capable of inputting the reference rotational speed power. a gear mechanism;
a connecting member externally fitted on the transmission shaft so as to be relatively rotatable about the axis,
The connecting member includes a planetary element other than the first sun gear and a planetary element forming a reference rotational speed power input portion of the first planetary gear mechanism, and the second sun gear and the reference rotation speed of the second planetary gear mechanism. A planetary gear assembly characterized by connecting a planetary element other than a planetary element forming a high-speed power input portion so as not to rotate relative to each other about an axis. the transmission shaft is operatively capable of receiving an HST output;
The connecting member includes a planetary element other than the first sun gear and the planetary element forming the reference rotational speed power input portion of the first planetary gear mechanism, and a second sun gear and the reference rotational speed of the second planetary gear mechanism. 2. The power input part according to claim 1, further comprising: a connecting body for connecting planetary elements other than the planetary elements forming the power input section; and an output body capable of outputting the rotational power of the connecting body to the outside. planetary gear assembly. the connecting member is operatively capable of receiving an HST output;
2. The planetary gear assembly according to claim 1, wherein said transmission shaft is capable of outputting rotational power around its own axis to the outside. the transmission shaft is a cylindrical shaft capable of operatively inputting an HST output,
The planetary gear assembly is provided with an output shaft to which the transmission shaft is externally inserted so as to be relatively rotatable about an axis,
The connecting member includes a planetary element other than the first sun gear and a planetary element forming a reference rotational speed power input portion of the first planetary gear mechanism, and the second sun gear and the reference rotation speed of the second planetary gear mechanism. A connecting body that connects planetary elements other than the planetary elements that form the high-speed power input section, and an output body capable of outputting the rotational power of the connecting body to the outside,
3. A planetary gear assembly according to claim 2, wherein said output body is coaxial with said output shaft and is not rotatable relative to said output shaft. A reference rotational speed power operatively input to the pump shaft from a drive source is steplessly changed between the first HST speed and the second HST speed, and the HMT outputs the HST output after the speed change from the motor shaft in cooperation with the HST. A planetary gear assembly forming a device comprising:
a transmission shaft to which an HST output can be operatively input;
A first element supported by the transmission shaft so as not to rotate relative to the axis, a second element to which a reference rotational speed power can be input, and a combined rotational power obtained by synthesizing the rotational powers input to the first and second elements. a first planetary gear mechanism having a third element that outputs
A first element supported by the transmission shaft so as not to rotate relative to the axis, a second element to which a reference rotational speed power can be input, and a combined rotational power obtained by synthesizing the rotational powers input to the first and second elements. a second planetary gear mechanism having a third element that outputs
a connecting member externally fitted on the transmission shaft so as to be relatively rotatable about the axis,
The connecting member has a connecting body that connects the third elements of the first and second planetary gear mechanisms, and an output body capable of outputting rotational power of the connecting body to the outside. planetary gear assembly. An input member connected to the second element of the second planetary gear mechanism in a state that is rotatable relative to the transmission shaft about the axis,
The input member has first and second input gears capable of inputting reference rotational speed power,
6. The planetary gear assembly according to claim 5, wherein the pitch diameter of said second input gear portion is smaller than the pitch diameter of said first input gear portion. The first planetary gear mechanism has a first sun gear acting as a first element, a first carrier acting as a third element, and a first internal gear acting as a second element,
The second planetary gear mechanism has a second sun gear acting as a first element, a second carrier acting as a second element, and a second internal gear acting as a third element,
The first planetary gear mechanism accelerates the first carrier in a first rotation direction, which is one side about the axis, as the HST output changes from the first HST speed side to the second HST speed side under the transmission state. and the first carrier rotates in the first rotation direction at the predetermined first speed maximum speed when the HST output is set to the predetermined first speed maximum speed HST speed. is set and
In the second planetary gear mechanism, the second internal gear rotates in the first rotation direction at the first speed maximum speed when the HST output is set to the first speed maximum speed HST speed in the transmission state. Further, as the HST output changes from the HST speed for the highest speed of the first speed stage toward the first HST speed to the predetermined HST speed for the highest speed of the second speed stage, the rotation speed of the second internal gear increases to the second HST speed. 7. A planetary gear assembly according to claim 5 or 6, wherein the gear ratio is set so as to increase the speed from the maximum speed of the first speed stage to the maximum speed of the second speed stage. The connecting body includes a cylindrical portion extending in the axial direction, a first flange extending radially outward from a first side in the axial direction of the cylindrical portion and connected to the first carrier, and a first flange in the axial direction of the cylindrical portion. 8. A planetary gear assembly according to claim 7, further comprising a second flange extending radially outwardly from two sides and connected to said second internal gear. The output body is arranged axially opposite to the connecting body with respect to the first planetary gear supported by the first carrier, and is axially non-rotatable on the first side of the connecting body in the axial direction. 9. A planetary gear assembly according to claim 7, further comprising a connecting flange to be connected, and a shaft portion extending axially from the connecting flange to the first side. a transmission gear member externally fitted on the shaft portion so as to be relatively rotatable about the axis;
The transmission gear member has an input gear portion for inputting the reference rotation speed power that is operationally input from the drive source, and an output gear portion that meshes with the first internal gear. 10. The planetary gear assembly of claim 9. An HST driven gear is provided which is non-rotatably supported on a second side in the axial direction from a portion of the transmission shaft that supports the second planetary gear mechanism and is capable of receiving an HST output. Item 11. A planetary gear assembly according to any one of items 5 to 10. The gear ratio of the first planetary gear mechanism is set so that the third element becomes zero speed when the HST output is set to the predetermined HST speed for zero speed under the transmission state. A planetary gear assembly as claimed in any one of claims 5 to 11. 13. The planetary gear assembly according to claim 12, wherein the HST speed for zero speed is a speed shifted from the first HST speed toward the second HST speed by a predetermined speed. A reference rotational speed power operatively input to the pump shaft from a drive source is steplessly changed between the first HST speed and the second HST speed, and the HMT outputs the HST output after the speed change from the motor shaft in cooperation with the HST. A planetary gear assembly forming a device comprising:
a transmission shaft;
a first planetary gear mechanism having a first element supported by the transmission shaft so as not to rotate relative to the axis, a second element to which a reference rotational speed power can be input, and a third element to which an HST output can be input; ,
a second planetary gear mechanism having a first element supported by the transmission shaft so as not to rotate relative to the axis, a second element to which a reference rotational speed power can be input, and a third element to which an HST output can be input; ,
a connecting member that is externally fitted around the transmission shaft so as to be relatively rotatable about the axis,
the connecting member is operatively capable of receiving an HST output and connects the third elements of the first and second planetary gear mechanisms;
A planetary gear assembly, wherein said transmission shaft acts as a common HMT output member for both said first and second planetary gear mechanisms. an HST that continuously shifts the reference rotational speed power operatively input to the pump shaft from the drive source between the first HST speed and the second HST speed, and outputs the HST output after shifting from the motor shaft;
a drive shaft to which reference rotational speed power is operatively transmitted from the drive source;
a transmission shaft;
It has three planetary elements including a first sun gear, a first carrier, and a first internal gear, wherein the first sun gear is supported by the transmission shaft so as not to rotate relative to the axis, and the first carrier and the first internal gear. a first planetary gear mechanism that forms a reference rotational speed power input section in which one of the gears is capable of inputting the reference rotational speed power;
planetary three elements including a second sun gear, a second carrier and a second internal gear, the second sun gear being supported by the transmission shaft so as not to rotate relative to the axis, the second carrier and the second internal gear; Among the gears, a second planetary element forming a reference rotational speed power input section to which a planetary element different from the planetary element forming the reference rotational speed power input section in the first planetary gear mechanism is capable of inputting the reference rotational speed power. a gear mechanism;
a first transmission gear train capable of operatively transmitting a reference rotation speed power from the drive shaft to a reference rotation speed power input portion of the first planetary gear mechanism;
a first clutch mechanism that engages and disengages power transmission by the first transmission gear train;
a second transmission gear train capable of operatively transmitting a reference rotational speed power from the drive shaft to a reference rotational speed power input portion of the second planetary gear mechanism;
a second clutch mechanism that engages and disengages power transmission by the second transmission gear train;
a connecting member externally fitted on the transmission shaft so as to be relatively rotatable about the axis,
The connecting member includes a planetary element other than the first sun gear and a planetary element forming a reference rotational speed power input portion of the first planetary gear mechanism, and the second sun gear and the reference rotation speed of the second planetary gear mechanism. An HMT device characterized by connecting a planetary element other than the planetary element forming the high-speed power input portion so as not to be relatively rotatable about the axis. the transmission shaft is operatively capable of receiving an HST output;
The connecting member includes a planetary element other than the first sun gear and a planetary element forming a reference rotational speed power input portion of the first planetary gear mechanism, and the second sun gear and the reference rotation speed of the second planetary gear mechanism. 16. The method according to claim 15, further comprising: a connecting body for connecting planetary elements other than the planetary elements forming the high-speed power input portion; and an output body capable of outputting the rotational power of the connecting body to the outside. HMT device as described. the connecting member is operatively capable of receiving an HST output;
16. The HMT device according to claim 15, wherein the transmission shaft is capable of outputting rotational power around its own axis to the outside. the transmission shaft is a cylindrical shaft capable of operatively inputting an HST output,
The HMT device is provided with an output shaft for externally inserting the transmission shaft so as to be relatively rotatable about an axis,
The connecting member includes a planetary element other than the first sun gear and a planetary element forming a reference rotational speed power input portion of the first planetary gear mechanism, and the second sun gear and the reference rotation speed of the second planetary gear mechanism. A connecting body that connects planetary elements other than the planetary elements that form the high-speed power input section, and an output body capable of outputting the rotational power of the connecting body to the outside,
16. The HMT device according to claim 15, wherein the output member is coaxial with the output shaft and is not relatively rotatable about the axis. an HST that continuously shifts the reference rotational speed power operatively input to the pump shaft from the drive source between the first HST speed and the second HST speed, and outputs the HST output after shifting from the motor shaft;
a drive shaft to which reference rotational speed power is operatively transmitted from the drive source;
a transmission shaft to which an HST output is operatively transmitted from the motor shaft;
A first element supported by the transmission shaft so as not to rotate relative to the axis, a second element to which a reference rotational speed power can be input, and a combined rotational power obtained by synthesizing the rotational powers input to the first and second elements. a first planetary gear mechanism having a third element that outputs
a first transmission gear train capable of operatively transmitting the reference rotational speed power from the drive shaft to the second element of the first planetary gear mechanism;
a first clutch mechanism that engages and disengages power transmission by the first transmission gear train;
A first element supported by the transmission shaft so as not to rotate relative to the axis, a second element to which a reference rotational speed power can be input, and a combined rotational power obtained by synthesizing the rotational powers input to the first and second elements. a second planetary gear mechanism having a third element that outputs
a second transmission gear train capable of operatively transmitting the reference rotational speed power from the drive shaft to the second element of the second planetary gear mechanism;
a second clutch mechanism that engages and disengages power transmission by the second transmission gear train;
a connecting member that connects the third elements of the first and second planetary gears so as not to rotate relative to each other about the axis;
The connecting member has a first axial side connected to the third element of the first planetary gear mechanism and a second axial side connected to the second planetary gear mechanism in a state in which the connecting member is fitted around the transmission shaft so as to be relatively rotatable about the axis. An HMT device, comprising: a connecting body connected to a third element of a gear mechanism; and an output body capable of outputting rotational power of the connecting body to the outside. The first planetary gear mechanism has a first sun gear acting as a first element, a first carrier acting as a third element, and a first internal gear acting as a second element,
The second planetary gear mechanism has a second sun gear acting as a first element, a second carrier acting as a second element, and a second internal gear acting as a third element,
In the first planetary gear mechanism, when the HST output is set to a predetermined HST speed for zero speed under the transmission state, the first carrier becomes zero speed, and the HST output changes from the first HST speed side to the second HST speed side. As it changes to the side, the first carrier rotates at an accelerated speed in the first rotation direction, which is one side about the axis, and when the HST output is set to the predetermined HST speed for the first speed stage highest speed, the first speed is increased. A gear ratio is set so that one carrier rotates in a first rotation direction at a predetermined first gear maximum speed,
In the second planetary gear mechanism, the second internal gear rotates in the first rotation direction at the first speed maximum speed when the HST output is set to the first speed maximum speed HST speed in the transmission state. Further, as the HST output changes from the HST speed for the highest speed of the first speed stage toward the first HST speed to the predetermined HST speed for the highest speed of the second speed stage, the rotation speed of the second internal gear increases to the second HST speed. 20. The HMT device according to claim 19, wherein the gear ratio is set so as to increase the speed from the maximum speed of the first speed stage to the maximum speed of the second speed stage. The connecting body includes a cylindrical portion extending in the axial direction, a first flange extending radially outward from a first side in the axial direction of the cylindrical portion and connected to the first carrier, and a first flange in the axial direction of the cylindrical portion. 21. The HMT device of claim 20, further comprising a second flange extending radially outwardly from two sides and connected to the second internal gear. The drive shaft is coaxially connected to the pump shaft so as not to rotate relative to the axis,
The transmission shaft is arranged parallel to the drive shaft,
The first transmission gear train includes: a first drive gear supported by the drive shaft so as to be axially rotatable; and a first drive gear that is operatively meshed with the first drive gear and non-rotatably axially relative to the first internal gear. and a first driven gear supported directly or indirectly on the transmission shaft so as to be relatively rotatable about the axis while being connected to the
The first clutch mechanism is provided on the drive shaft so as to engage and disengage power transmission from the drive shaft to the first drive gear,
The second transmission gear train includes: a second drive gear supported axially rotatably on the drive shaft; and an axially non-rotatably connected second carrier operatively meshed with the second drive gear. and a second driven gear supported directly or indirectly on the transmission shaft in a state where the
22. The HMT device according to claim 20, wherein said second clutch mechanism is provided on said drive shaft so as to engage and disengage power transmission from said drive shaft to said second drive gear. . the first and second clutch mechanisms are arranged axially between the first and second flanges of the connecting body;
3. A part of said first and second clutch mechanisms enters into a space defined by an outer peripheral surface of said cylindrical portion and opposing surfaces of said first and second flanges. 23. The HMT device according to 22. a third transmission gear train capable of operatively transmitting the reference rotational speed power from the drive shaft to the second carrier;
a third clutch mechanism that engages and disengages power transmission by the third transmission gear train,
The third transmission gear train includes a third driving gear supported by the driving shaft so as to be axially rotatable relative to each other, and is operatively meshed with the third driving gear and connected to the second carrier so as not to be relatively rotatable around the axis. and a third driven gear supported directly or indirectly on the transmission shaft so as to be relatively rotatable about the axis in a state where the transmission gear is connected, and the gear rotates the second carrier at a higher speed than the second transmission gear train. ratio is set
24. The HMT device according to claim 22, wherein the third clutch mechanism is provided on the drive shaft so as to engage or disengage power transmission from the drive shaft to the third drive gear. . An input member connected to the second element of the second planetary gear mechanism in a state that is rotatable relative to the transmission shaft about the axis,
25. The HMT device of claim 24, wherein said second and third driven gears are provided on said input member. an HMT device according to any one of claims 19 to 25;
a shift operating member that can be manually operated in a shift operation range between the zero speed position and the maximum speed position;
an operating position sensor that detects an operating position of the shift operating member;
a first clutch actuating member that switches engagement/disengagement operation of the first clutch mechanism;
a second clutch actuating member for switching engagement and disengagement of the second clutch mechanism;
an HST actuating member that actuates the output adjusting member of the HST;
an output sensor that directly or indirectly detects the rotation speed of the connecting member;
a control device that controls the operation of the first and second clutch actuating members and the HST actuating member;
The shift operation range includes a first gear operation area on the low speed side set from the zero speed position to the first gear highest speed position, and a low speed side first gear operating area set from the first gear highest speed position to the second gear highest speed position. It is divided into the second speed stage operation area on the high speed side set in the range up to
When the gear shift operating member is operated in the first gear operation region, the control device brings the first clutch mechanism into an engaged state and the second clutch mechanism into a disengaged state, and shifts the gear shift operating member. is positioned at the highest speed position of the first speed stage, one of the first and second clutch mechanisms is in the engaged state and the other is in the disengaged state, and the shift operation member operates the second speed stage. actuating the first and second clutch actuating members so that the first clutch mechanism is in the disengaged state and the second clutch mechanism is in the engaged state when operated in the region;
When the shift operating member is operated to the zero speed position, the HST output becomes the HST speed for zero speed. The output is shifted from the 1st HST speed side to the 2nd HST speed side, and the HST output becomes the 1st speed highest speed HST speed in response to the operation of the shift operation member to the 1st speed highest speed position, The HST output is shifted from the second HST speed side to the first HST speed side in accordance with the operation of the speed change operation member to the speed increasing side within the second gear operation region, and the speed change operation member is positioned at the maximum speed. and operating the HST operation member so that the HST output becomes the HST speed for the highest speed of the second speed stage according to the operation of the transmission structure. Forward/backward movement capable of selectively taking a normal rotation output state in which the HMT power operatively input from the output body is output without changing the rotation direction, and a reverse rotation output state in which the HMT power is output with the rotation direction reversed. a switching mechanism;
a forward/reverse operation member that operates the forward/reverse switching mechanism;
The shift operation range of the shift operation member includes a forward operation range from the zero speed position to the forward maximum speed position and a reverse operation range from the zero speed position to the reverse maximum speed position,
The control device sets the forward/reverse switching mechanism to a forward rotation output state when the speed change operation member is positioned in the forward operation range, and when the speed change operation member is positioned in the reverse operation range. 27. The transmission structure according to claim 26, wherein the forward/reverse operation member is operated so that the forward/reverse switching mechanism is in a reverse output state. 28. The transmission structure according to claim 26 or 27, further comprising a subtransmission mechanism capable of shifting the HMT power operatively input from said output body to a plurality of gear stages including a low speed stage and a high speed stage.

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