JP6843338B2 - HMT unit and HMT structure - Google Patents

Description

The present invention relates to a hydrostatic / mechanical continuously variable transmission unit (HMT unit) having a hydrostatic continuously variable transmission mechanism (HST) and a planetary gear mechanism.

HMT, which is a combination of HST and planetary gear mechanism, is used for the traveling system transmission path of work vehicles such as combines and tractors for the purpose of improving transmission efficiency as much as possible while enabling continuously variable transmission from zero initial speed. There is.

Further, an HMT in which the rotation direction of the combined rotational power output from the planetary gear mechanism can be switched forward or reverse according to the operation of the volume changing member in the HST has also been proposed (see Patent Document 1 below).

The HMT in which the rotation direction of the combined rotational power can be switched between forward and reverse can enable the vehicle to travel forward and backward by operating the volume changing member without providing a forward / backward switching mechanism in the traveling system transmission path. Useful in terms of points.

However, in the HMT described in Patent Document 1, the planetary gear mechanism is housed in the transmission case together with the auxiliary transmission mechanism, while the HST is connected to the outer wall surface of the mission case.

In such a configuration, the HMT output adjustment work cannot be performed until the planetary gear mechanism is incorporated in the mission case and the HST is mounted in the mission case, and the assembly work efficiency including the adjustment work is poor. There's a problem.

In particular, in the HMT described in Patent Document 1, the rotation direction of the combined rotational power can be switched between forward and reverse. , It is necessary to strictly adjust the meshing of the gears of the planetary gear mechanism.

Specifically, the HMT described in Patent Document 1 has a pump-side movable swash plate and a motor-side movable swash plate as volume changing members of the HST, and the motor-side movable swash plate is positioned at the first tilting position. In the state of being moved, the combined rotational power is steplessly changed from zero to the maximum speed in the forward direction by swinging the movable swash plate on the pump side from the maximum tilt position in the reverse direction to the maximum tilt position in the normal rotation direction via the neutral position. With the speed changed and the pump-side movable swash plate positioned at the maximum tilt position in the reverse direction, the motor-side movable swash plate is moved from the first tilt position closer to the neutral position than the first tilt position. By swinging to the second tilting position, the combined rotational power is continuously variable from zero to the maximum speed in the reverse direction.

In such an HMT, it is necessary to strictly perform the assembly work and the adjustment work of the HST and the planetary gear mechanism so that the combined rotational power of the HMT becomes zero in a predetermined output state in which the HST is not in the neutral state.

However, in the HMT described in Patent Document 1, as described above, the output adjustment work cannot be performed unless the planetary gear mechanism is assembled in the mission case and the HST is mounted in the mission case. Such adjustment work becomes troublesome.

Japanese Patent No. 4988111

The present invention has been made in view of the above-mentioned prior art, and is an HMT unit having an HST and a planetary gear mechanism, and the HST and the planetary gears are not actually assembled at a mounting location such as a transmission including an auxiliary transmission mechanism or the like. It is an object of the present invention to provide an HMT unit capable of assembling a mechanism and adjusting an output.

Further, the present invention has an HMT structure including an HMT unit having an HST and a planetary gear mechanism and a transmission to which the HMT unit is detachably connected, without actually assembling the HMT unit to the transmission. , HST and planetary gear mechanism assembly work and output adjustment work can be performed for the purpose of providing an HMT structure.

In the present invention, in order to achieve the above object, the HST that continuously shifts and outputs the rotational power input from the drive source, the rotational power from the drive source, and the rotational power from the HST are combined and output. The planetary gear mechanism includes a sun gear that is actuated and connected to the motor shaft of the HST, a planet gear that meshes with the sun gear, an internal gear that meshes with the planet gear, and the planet gear. An HMT unit that rotatably supports the planet gear and has a carrier that rotates around the axis of the sun gear in conjunction with the revolution of the planet gear around the sun gear, wherein the HST and the planet gear mechanism The HST includes a pump shaft, a hydraulic pump supported by the pump shaft, a hydraulic motor fluidly connected to the hydraulic pump, and the HST. said motor shaft supporting the hydraulic motor, said and a volume changing member for changing the hydraulic pump and at least one of the volume of the hydraulic motor, the housing is integrally rotated before Kipo pump axis and about the axis An input shaft that inputs rotational power from the drive source in a state, a constant speed transmission unit that transmits the rotational power of the input shaft to a constant speed input element formed by one of the internal gear and the carrier, and the above. An output shaft for outputting the combined rotational power of the output element formed by the internal gear and the other of the carriers to the outside is provided, and the housing has first and second openings on one side and the other side in the first direction, respectively. A housing body having a hollow peripheral wall and a partition wall partitioning the internal space of the peripheral wall into a first chamber and a second chamber at an intermediate position in the first direction of the peripheral wall, and the housing main body so as to close the first opening. The hydraulic pump has a first lid member detachably connected to the housing body and a second lid member detachably connected to the housing body so as to close the second opening. The hydraulic motor and the volume changing member are housed, the planetary gear mechanism is housed in the second chamber, the pump shaft is along the first direction, and one side in the first direction is outward from the first lid member. The motor shaft is supported by the first lid member and the partition wall in a state of being extended to form the input shaft and the other side of the first direction plunges into the second chamber, and the motor shaft is along the first direction and is the first. The other side in the direction is supported by the first lid member and the partition wall in a state where the other side is rushed into the second chamber, and the constant speed transmission unit requires the constant speed input from the pump shaft. The output shaft is configured to actuately transmit rotational power, and in a state of being operatively connected to the output element, the other side in the first direction extends outward from the second lid member as an output unit. to provide a HMT unit you action.

For example, by operating the volume changing member, the combined rotational power is continuously changed between the maximum speed in the reverse rotation direction and the maximum speed in the forward rotation direction.

Preferably, the first lid member is formed with a pair of hydraulic oil passages that fluidly connect the hydraulic pump and the hydraulic motor.

Further, the present invention synthesizes an HST that continuously shifts and outputs a rotational power input from a drive source, a rotational power from the drive source, and a rotational power operatively input from the motor shaft of the HST to a sun gear. The housing includes a planetary gear mechanism for outputting, an HMT unit having a housing for accommodating the HST and the planetary gear mechanism, and a transmission having a transmission case to which the housing is detachably connected. An input shaft operatively connected to the pump shaft of the HST, a constant speed transmission unit operatively connected to the constant speed input element formed by one of the internal gear and the carrier of the planetary gear mechanism, and the inter. An output shaft that outputs the combined rotational power of the output element formed by the null gear and the other of the carriers to the outside is provided, and the transmission case includes a drive shaft that operatively inputs rotational power from the drive source. , The transmission input shaft is provided, and by connecting the housing to the transmission case, the drive shaft is connected to the input shaft via the first coupling, and the output shaft is connected to the transmission input via the second coupling. Each of the shafts is provided with an HMT structure connected to the shaft.

For example, the first coupling and the second coupling are provided in the mission case.
Instead, one or both of the first coupling and the second coupling can be provided in the housing.

The HST includes the pump shaft, a hydraulic pump supported by the pump shaft, a hydraulic motor fluidly connected to the hydraulic pump, the motor shaft supporting the hydraulic motor, the hydraulic pump, and the hydraulic motor. It is assumed that the HST and the planetary gear mechanism have a volume changing member that changes the volume of at least one of the pumps, and preferably, the rotation speed of the motor shaft is changed by operating the volume changing member. The combined rotational power output from the output shaft is set so as to be steplessly changed between the maximum speed in the reverse rotation direction and the maximum speed in the forward rotation direction.

According to the HMT unit according to the present invention, the HST and the planetary gear mechanism are housed in a state where the sun gear is operatively connected to the motor shaft, and the housing is provided which is detachably connected to the mounting location while the sun gear is housed. ,
The HST includes a pump shaft, a hydraulic pump supported by the pump shaft, a hydraulic motor fluidly connected to the hydraulic pump, the motor shaft supporting the hydraulic motor, and the hydraulic pump and the hydraulic motor. at least one of and a volume changing member for changing the volume in the housing, the front input shaft for inputting a rotational power from said driving source in a state of integrally rotating the Kipo pump axis and about the axis, the input A constant speed transmission unit that operates and transmits the rotational power of the shaft to a constant speed input element formed by one of the internal gear and the carrier of the planetary gear mechanism, and an output element formed by the internal gear and the other of the carrier. An output shaft for outputting the combined rotational power to the outside is provided, and the housing is located at an intermediate position between the hollow peripheral wall having the first and second openings on one side and the other side in the first direction and the peripheral wall in the first direction. A housing body having a partition wall for partitioning the internal space of the peripheral wall into a first chamber and a second chamber, a first lid member detachably connected to the housing body so as to close the first opening, and the first lid member. It has a second lid member that is detachably connected to the housing body so as to close the two openings, and the hydraulic pump, the hydraulic motor, and the volume changing member are housed in the first chamber, and the second. The chamber accommodates the planetary gear mechanism, and the pump shaft is along the first direction, one side of the first direction extending outward from the first lid member to form the input shaft and the other in the first direction. The motor shaft is supported by the first lid member and the partition wall with the side plunging into the second chamber, and the motor shaft is along the first direction and the other side of the first direction plunges into the second chamber. Supported by the lid member and the partition wall, the constant speed transmission unit is configured to actuate and transmit rotational power from the pump shaft to the constant speed input element, and the output shaft is operatively connected to the output element. state, Runode to act as an output unit is extended outward from the first direction the other side the second lid member, without actually be attached to the attachment point of the transmission such as the HST and the planetary gear mechanism, The HST and the planetary gear mechanism can be assembled and the output can be adjusted, and the efficiency of these operations can be improved.

Further, according to the HMT structure according to the present invention, a transmission case in which the housing is detachably connected to the HMT unit in which the HST and the planetary gear mechanism are housed in a housing in a state where the sun gear is operatively connected to the motor shaft. The housing comprises an input shaft operatively connected to the pump shaft of the HST and a constant speed input element formed by one of the internal gear and the carrier of the planetary gear mechanism. A constant speed transmission unit that is actuated and connected and an output shaft that outputs the combined rotational power of the output element formed by the internal gear and the other of the carriers to the outside are provided, and the transmission case rotates from the drive source. A drive shaft for operatively inputting power and a transmission input shaft are provided, and by connecting the housing to the transmission case, the drive shaft is connected to the input shaft via a first coupling, and the output shaft is connected to the input shaft. Since the HST and the HST unit having the planetary gear mechanism are respectively connected to the transmission input shaft via the two couplings, the HST and the planetary gear mechanism can be assembled without actually mounting the HST and the HST unit having the planetary gear mechanism on the transmission. And output adjustment work can be performed, and these work efficiencies can be improved.

FIG. 1 is a perspective view showing a state in which the HMT unit according to the first embodiment of the present invention is mounted on the transmission. FIG. 2 is a developed sectional view of the HMT unit and the transmission according to the first embodiment. FIG. 3 is an exploded development sectional view of the HMT unit separated from the transmission. FIG. 4 is a cross-sectional view of the HMT unit along the IV-IV line in FIG. FIG. 5 is an enlarged cross-sectional view of the planetary gear mechanism in the HMT unit. FIG. 6 is a cross-sectional view taken along the line VI-VI in FIG. FIG. 7 is a cross-sectional view taken along the line VII-VII in FIG. FIG. 8 is an exploded cross-sectional view of the planetary gear mechanism. FIG. 9 is a developed sectional view of a state in which the HMT unit according to the second embodiment of the present invention is mounted on the transmission. FIG. 10 is an exploded exploded sectional view of the HMT unit according to the second embodiment separated from the transmission. FIG. 11 is an enlarged cross-sectional view of the planetary gear mechanism in the HMT unit according to the second embodiment. FIG. 12 is a perspective view showing a state in which the HMT unit according to the second embodiment is mounted on the transmission according to the modified example. FIG. 13 is a developed cross-sectional view of FIG. FIG. 14 is an exploded development sectional view of FIG. 13. 15 (a) is a partially enlarged developed cross-sectional view of FIGS. 13 and 14. FIG. 15 (b) is a partially enlarged developed cross-sectional view of a modified example of FIG. 15 (a). FIG. 15 (c) is a partially enlarged developed sectional view of another modified example of FIG. 15 (a). FIG. 16 is an exploded development sectional view of a state in which the HMT unit according to the modified example of the second embodiment is separated from the transmission.

Embodiment 1
Hereinafter, an embodiment of the HMT unit according to the present invention will be described with reference to the accompanying drawings.
1 and 2 show a perspective view and a developed sectional view of a state in which the HMT unit 1 according to the present embodiment is mounted on the transmission 500, respectively.
Further, FIG. 3 shows a disassembled and developed cross-sectional view of the HMT unit 1 separated from the transmission 500, and FIG. 4 shows a cross-sectional view of the HMT unit 1 along the IV-IV line in FIG.

As shown in FIGS. 1 to 4, the HMT unit 1 has an HST 10 that continuously changes and outputs a rotational power input from a drive source (not shown), a rotational power from the drive source, and the HST 10. The planetary gear mechanism 100 that synthesizes and outputs the rotational power from the above, and the housing 200 that is detachably connected to the mounting location (the transmission 500 in the illustrated example) while accommodating the HST 10 and the planetary gear mechanism 100. And have.

As shown in FIGS. 2 and 4, the HST 10 includes a pump shaft 20 that is operatively driven to rotate by a drive source, a hydraulic pump 25 that is non-rotatably supported by the pump shaft 20, and the hydraulic pump 25. A hydraulic motor 35 that is fluidly connected to the hydraulic pump 25 and hydraulically driven to rotate by the hydraulic pump 25, a motor shaft 30 that supports the hydraulic motor 35 so as to be relatively non-rotatable, and at least one of the hydraulic pump 25 and the hydraulic motor 35. 40, which changes the volume of the pump shaft 20 to steplessly change the ratio of the output rotation speed output from the motor shaft 30 to the input rotation speed input to the pump shaft 20 (that is, the gear ratio by HST). And have.

In the present embodiment, the HST 10 is a pump-side movable swash plate 40 (P) for changing the volume of the hydraulic pump 25 and a motor-side movable swash plate for changing the volume of the hydraulic motor 35 as the volume changing member 40. It has a plate 40 (M).

FIG. 5 shows an enlarged cross-sectional view of the planetary gear mechanism 100.
Further, FIG. 6 shows a cross-sectional view taken along the line VI-VI in FIG. 5, and FIG. 7 shows a cross-sectional view taken along the line VII-VII in FIG.

As shown in FIG. 5 and the like, the planetary gear mechanism 100 rotates around the sun gear 110, the planet gear 120 that meshes with the sun gear 110, the internal gear 130 that meshes with the planet gear 120, and the planet gear 120. It has a carrier 150 that is rotatably supported and rotates around the axis of the sun gear 110 in conjunction with the revolution of the planet gear 120 around the sun gear 110.

In the planetary gear mechanism 100, one element of the three planetary elements of the sun gear 100, the carrier 150, and the internal gear 130 acts as a variable input element, and the other element acts as a constant input element. The remaining one element acts as a synthetic rotational power output element.

In the present embodiment, the sun gear 100 is non-rotatably supported by the motor shaft 30 and acts as a variable input element, the internal gear 130 acts as a constant speed input element, and the carrier 150 performs synthetic rotation. Acts as a power output element.

As shown in FIG. 5, in the present embodiment, the carrier 150 includes a carrier pin 160 that rotatably supports the planetary gear 120 around the axis, and the sun gear along with the revolution of the planetary gear 120 around the sun gear 110. The first and second portions supporting the first end 162 (1) on one side of the carrier pin 160 in the axial direction and the second end 162 (2) on the other side in the axial direction so as to rotate around the axis of 110, respectively. It has carrier bodies 170 (1) and 170 (2).

The first carrier body 170 (1) has a first support hole 172 (1) into which the first end portion 162 (1) of the carrier pin 160 is inserted, and a first end portion 162 (1) of the carrier pin 160. The first stop surface 175 (1) that engages with the first contact surface 165 (1) facing one side in the axial direction of the carrier pin 160 with the 1) inserted into the first support hole 172 (1). And are provided.

On the other hand, the second carrier main body 170 (2) has a second support hole 172 (2) into which the second end portion 162 (2) of the carrier pin 160 is inserted, and a second end portion of the carrier pin 160. The second stop surface 175 (2) that engages with the second contact surface 165 (2) facing the other side in the axial direction of the carrier pin 160 with the 162 (2) inserted into the second support hole 172 (2). 2) and are provided.

In the first and second carrier main bodies 170 (1) and 170 (2), the first end portion 162 (1) is engaged in the first support hole 172 (1) and the first contact surface 165. (1) is engaged with the first stop surface 175 (1), the second end portion 162 (2) is engaged with the second support hole 172 (2), and the second contact surface 165 (1) 2) is detachably connected to each other via a fastening member 178 in a state of being engaged with the second stop surface 175 (2).

According to the planetary gear mechanism 100 having such a configuration, the load applied to the carrier pin 160 and the retaining structure of the carrier pin 160 can be effectively reduced, and the durability can be improved.

That is, in the conventional planetary gear mechanism, the carrier pin is in a cantilever support state in which one side in the axial direction is inserted and supported in a support hole formed in the carrier body such as a carrier gear and the other side in the axial direction supports the planetary gear. It is said that.
In such a conventional configuration, a large load is applied to the carrier pin itself.

Further, in the conventional planetary gear mechanism, the carrier pin is generally prevented from coming off from the support hole by a retaining pin that is detachably attached to the carrier pin. Is heavily loaded in the shearing direction.

On the other hand, in the present embodiment, in the carrier pin 160, the first and second end portions 162 (1) and 162 (2) are the first support holes 172 of the first carrier main body 170 (1), respectively. In the double-sided support state inserted into the second support hole 172 (2) of the second carrier main body 170 (2) and the first and second end portions 162 (1) and 162 (2). The planetary gear 120 is supported in the middle portion between the two.
Therefore, the load applied to the carrier pin 160 can be effectively reduced.

Further, in the present embodiment, the first contact surface 165 (1) comes into contact with the first stop surface 175 (1) to prevent the carrier pin 160 from coming off to one side in the axial direction. In addition, the second contact surface 165 (2) comes into contact with the second stop surface 175 (2) to prevent the carrier pin 160 from coming off to the other side in the axial direction.
Therefore, the carrier pin 160 can be prevented from coming off without applying an excessive load to the specific member such as the retaining pin.

FIG. 8 shows an exploded cross-sectional view of the planetary gear mechanism 100.
In the present embodiment, as shown in FIG. 8, the first support hole 172 (1) has the second carrier main body 170 (2) on the inner end side in the axial direction close to the second carrier main body 170 (2). ), And the outer end side in the axial direction opposite to the second carrier main body 170 (2) ends within the axial thickness of the first carrier main body 170 (1). It has a portion 173 (1) and a bottom surface 174 (1) extending inward in the radial direction from the outer end side in the axial direction of the hole portion 173 (1).

Similarly, the second support hole 172 (2) is opened at the inner end side in the axial direction close to the first carrier main body 170 (1) on the surface 170a (2) facing the first carrier main body 170 (1). In addition, the hole portion 173 (2) and the hole portion 173 whose axial outer end side opposite to the first carrier main body 170 (1) ends within the axial thickness of the second carrier main body 170 (2). It has a bottom surface 174 (2) extending inward in the radial direction from the outer end side in the axial direction of (2).

The first end portion 162 (1) of the carrier pin 160 is said so that the end surface 164 (1) on one side in the axial direction is in contact with the bottom surface 174 (1) of the first support hole 172 (1). The second end portion 162 (2) of the carrier pin 160 is inserted into the hole portion 173 (1) of the first support hole 172 (1), and the end surface 164 (2) on the other side in the axial direction is the second end surface 164 (2). It is inserted into the hole portion 173 (2) of the second support hole 172 (2) so as to come into contact with the bottom surface 174 (2) of the support hole 172 (2).

That is, in the present embodiment, the end faces 164 (1) and 164 (2) on one side and the other side in the axial direction of the carrier pin 160 are the first and second contact surfaces 165 (1), respectively. Acting as 165 (2), the bottom surfaces 174 (1) and 174 (2) of the first and second support holes 172 (1) and 172 (2) form the first and second stop surfaces 175 (1) and 174 (2), respectively. 1) Acts as 175 (2).

The planetary gear mechanism 100 is provided with the following lubricating oil supply structure.
As shown in FIGS. 5 to 8, the first carrier main body 170 (1) extends from the radial inner end of the bottom surface 174 (1) of the first support hole 172 (1) to the axial outer end side. A first oil hole 176 (1) is provided in the back surface 170b (1) of the first carrier body 170 (1) opposite to the second carrier body 170 (2).

Similarly, the second carrier main body 170 (2) extends from the radial inner end of the bottom surface 174 (2) of the second support hole 172 (2) to the axial outer end side to the second carrier main body 170. A second oil hole 176 (2) is provided on the back surface 170b (2) on the opposite side of the first carrier body 170 (1) of (2).

By providing the first and second oil holes 176 (1) and 176 (2), the stored oil stored in the portion of the housing 200 that accommodates the planetary gear mechanism 100 is stored in the carrier pin 160. It can be effectively guided to the 1st and 2nd end portions 162 (1) and 162 (2).

Further, in the planetary gear mechanism 100, the carrier pin 160 is opened on the end surface 164 (1) on one side in the axial direction so as to face the first oil hole 176 (1), and the second oil hole 176 (2) is opened. ) Is provided on the end surface 164 (2) on the other side in the axial direction, and a lubricating oil hole 166 is provided on the outer peripheral surface which is also opened in the region supporting the planetary gear 120.
By providing the lubricating oil hole 166, the lubricating oil can be effectively guided to the entire planetary gear mechanism 100.

Further, in the planetary gear mechanism 100, the following configuration is adopted in order to more smoothly supply the lubricating oil to the entire planetary gear mechanism 100.
That is, as shown in FIGS. 5 to 8, the lubricating oil holes 166 are the axial direction holes 166a opened in the end faces 164 (1) and 164 (2) on one side and the other side in the axial direction, and the axial direction holes 166a. Includes a radial hole 166b that opens on the outer peripheral surface on one end side and the other end side in a state of being communicated with.

Then, the carrier pin 160 is held in a posture along the radial direction R with respect to the rotation center of the sun gear 110 so that the radial hole 166b is held by the first and second carrier main bodies 170 (1). , 170 (2) is fixed to at least one of 170 (2) so as not to rotate around the axis.

In the present embodiment, as shown in FIGS. 5 to 8, the carrier pin 160 is provided with a detent pin 168 penetrating in the radial direction, and is included in the first carrier main body 170 (1). The radial hole 166b is formed by the planetary gear by engaging the detent pin 168 into the holding groove 185 formed on the surface (the surface facing the second carrier body 170 (2) 170a (1)). The rotation of the carrier pin 160 around the axis is prevented along the radial direction R of the mechanism.

By providing such a configuration, during the rotational operation of the carrier 150, the lubricating oil introduced into the axial hole 166a is radially along the entire planetary gear mechanism 100 through the radial hole 166b. It can be spread smoothly.

As described above, the carrier pin 160 is prevented from coming off in the thrust direction by engaging the first contact surface 165 (1) and the first stop surface 175 (1) and the second contact surface. Since this is performed by engaging the surface 165 (2) and the second stop surface 175 (2), the detent pin 168 is not required to have sufficient strength to prevent the carrier pin 160 from coming off, and the carrier. It is sufficient that the strength is sufficient to prevent the pin 160 from rotating around the axis.

As shown in FIGS. 2 and 3, the housing 200 includes an input shaft 310 for inputting rotational power from the drive source while rotating integrally with the pump shaft 20 of the HST 10 around an axis, and the input shaft 310. The constant speed transmission unit 330 that operates and transmits the rotational power of the above to the constant speed input element formed by one of the internal gear 130 and the carrier 150, and the output element formed by the other of the internal gear 130 and the carrier 150. An output shaft 350 is provided to output the combined rotational power of the above to the outside.

According to the HMT unit 1 having such a configuration, the HST 10 and the planetary gear mechanism 100 are assembled and adjusted by the HMT unit 1 alone without actually mounting the HST 10 and the planetary gear mechanism 100 on the vehicle. Can work.

That is, in the HST including the HST and the planetary gear mechanism, the constant speed rotational power is input to the first element of the three elements including the sun gear, the carrier and the internal gear in the planetary gear mechanism, and the third of the three elements. The stepless variable rotational power output from the HST is input to the two elements, and the combined rotational power is output from the third element of the three elements.

Therefore, the HST and the planetary gear mechanism are accurately assembled so that the operating amount of the volume changing member of the HST and the rotational speed of the combined rotational power output from the third element of the planetary gear mechanism have a desired relationship. It is necessary to strictly adjust the output.

In this regard, in the conventional HMT, the planetary gear mechanism is housed in the mission case accommodating the auxiliary transmission mechanism, while the HST is placed on the outer wall surface of the mission case in a state of being separated from the planetary gear mechanism. It is connected.

In such a conventional configuration, the HMT adjustment work cannot be performed until the planetary gear mechanism is incorporated in the mission case and the HST is mounted in the mission case, and the assembly work including the adjustment work cannot be performed. There is a problem of inefficiency.

On the other hand, according to the HMT unit 1 according to the present embodiment, the HST 10 and the planetary gear mechanism 100 can be assembled and adjusted by the HMT unit 1 alone, and the work efficiency thereof is improved. be able to.

In the specification that the combined rotational power of the planetary gear mechanism 100 can be switched forward and reverse by the output operation of the HST, it is necessary to perform the adjustment work more strictly, and the HMT unit 1 according to the present embodiment is described. The effect, that is, the effect that the HMT assembly work and the adjustment work can be performed by the HMT unit alone is particularly effective.

In the present embodiment, the combined rotational power of the planetary gear mechanism 100 can be switched forward and reverse by the HST output operation according to the following configuration.

That is, in the present embodiment, as described above, the HST 10 has the pump-side movable swash plate 40 (P) and the motor-side movable swash plate 40 (M) as the volume changing member 40. ..

The pump-side movable swash plate 40 (P) stops the rotation of the motor shaft 30 from the reverse rotation maximum tilt position that rotates the motor shaft 30 at the maximum speed in the reverse direction around the pump-side swing axis. The motor shaft 30 is configured to be tilted between the maximum tilt positions in the normal rotation direction in which the motor shaft 30 is rotated at the maximum speed in the normal rotation direction with the neutral position in between.

The motor-side movable swash plate 40 (M) tilts around the motor-side swing axis between a first tilting position and a second tilting position set to be neutral from the first tilting position. It is configured to be possible.

In such a configuration, the maximum tilt position in the forward rotation direction and the maximum tilt position in the reverse rotation direction of the pump-side movable tilt plate 40 (P), and the first and second tilt positions of the motor-side movable tilt plate 40 (M). The position and the gear ratio of the planetary gear mechanism 100 are the maximum in the reverse direction of the pump-side movable diagonal plate 40 (P) in a state where the motor-side movable diagonal plate 40 (M) is held in the first tilting position. According to the tilt from the tilt position to the maximum tilt position in the normal rotation direction, the rotation speed of the combined rotational power output from the planetary gear mechanism 100 changes steplessly from zero to the maximum speed in the normal rotation direction, and , The tilting of the motor-side movable swash plate 40 (M) from the first tilting position to the second tilting position while the pump-side movable swash plate 40 (P) is held at the maximum tilting position in the reverse direction. The rotational speed of the combined rotational power of the planetary gear mechanism 100 is set to shift steplessly from zero to the maximum speed in the reverse direction according to the above, whereby the combined rotational power of the planetary gear mechanism 100 is set. The rotation direction can be switched between the maximum speed in the reverse rotation direction and the maximum speed in the forward rotation direction, and stepless speed change is possible.

In this configuration, even when the pump-side movable diagonal plate 40 (P) is positioned in the neutral position and the output of the HST 10 (rotational speed of the motor shaft 30) is zero, the combined rotation of the planetary gear mechanism 100 The power has a predetermined rotational speed in the forward direction, the pump-side movable swash plate 40 (P) is at the maximum tilt position in the reverse direction, and the motor-side movable swash plate 40 (M) is at the first tilt position. When the HST 10 is in a predetermined output state, the combined rotational power of the planetary gear mechanism 100 becomes zero and the vehicle is stopped.

Therefore, it is necessary to perform the assembling work and the adjusting work of the HST 10 and the planetary gear mechanism 100 more strictly, and in such a specification, the HMT unit 1 according to the present embodiment is particularly useful.

As described above, since the HMT unit 1 according to the present embodiment can switch the rotation direction of the output rotational power in the forward and reverse directions, the transmission 500 on which the HMT unit 1 is mounted is mounted on the front and rear. It is not necessary to provide a forward switching mechanism.

As shown in FIG. 2 and the like, the transmission 500 has a transmission case 510, an auxiliary transmission mechanism 530 and a differential transmission mechanism 550 housed in the transmission case 510.

The auxiliary transmission mechanism 530 multi-speeds the rotational power from the output shaft 350 of the HMT unit 1.
In the present embodiment, as shown in FIG. 3, the mission case 510 is provided with a second coupling 530a, and the output shaft 350 of the HMT unit 1 is provided via the second coupling 530a. It is connected to the drive shaft of the auxiliary transmission mechanism 530.
That is, in the present embodiment, the drive shaft of the auxiliary transmission 530 acts as a transmission input shaft 505 that inputs the combined rotational power of the output shaft 350 of the HMT unit 1 via the second coupling 530a. doing.
The differential transmission mechanism 550 differentially transmits the rotational power from the auxiliary transmission mechanism 530 to the pair of left and right drive axles 580a and 580b.

The transmission 500 further selectively selectively applies a parking brake mechanism 560 capable of selectively applying a braking force to the driven shaft of the auxiliary transmission mechanism 530 and the pair of left and right drive axles 580a and 580b. It has a pair of left and right traveling brake mechanisms 570a and 570b to which braking force can be applied.

As shown in FIGS. 2 and 3, in the present embodiment, the housing 200 has a hollow peripheral wall 220 and the peripheral wall having first and second openings 221 and 222 on one side and the other side in the first direction, respectively. The housing body 210 having the partition wall 225 that divides the internal space of the peripheral wall 220 into the first chamber 200 (1) and the second chamber 200 (2) at the intermediate position in the first direction of the 220, and the first opening 221 are closed. It has a first lid member 230 detachably connected to the housing body 210 and a second lid member 250 detachably connected to the housing body 210 so as to close the second opening 222. ing.

The housing 200 accommodates the hydraulic pump 25, the hydraulic motor 35, and the volume changing member 40 in the first chamber 200 (1), and accommodates the planetary gear mechanism 100 in the second chamber 200 (2). ing.

In this case, the first lid member 230 is formed with a pair of hydraulic oil passages (not shown) for fluidly connecting the hydraulic pump 25 and the hydraulic motor 35.

In the present embodiment, as shown in FIGS. 2 and 3, the pump shaft 20 and the motor shaft 30 rush into the second chamber 200 (2) along the first direction and the other side in the first direction. In the state, it is supported by the first lid member 230 and the partition wall 225.

The input shaft 310 is arranged coaxially with the pump shaft 20 on the other side of the pump shaft 20 in the first direction and cannot rotate relative to the pump shaft 20 around the axis. It extends outward from the second lid member 250 and acts as an input unit that is actuated and connected to the drive source.

In the present embodiment, as shown in FIG. 3, the input shaft 310 is a shaft separate from the pump shaft 20, and is detachably connected to the pump shaft 20 via the tubular connecting shaft 315. Has been done.

Specifically, the tubular connecting shaft 315 has a spline on the inner peripheral surface, and the facing ends of the pump shaft 20 and the input shaft 310 are splines that mesh with the spline of the tubular connecting shaft 315 on the outer peripheral surface. have.

Alternatively, the input shaft 310 and the pump shaft 20 can be formed by a single shaft.
In this case, the single shaft supports the hydraulic pump 25 at a portion located in the first chamber 200 (1) and penetrates the second chamber 200 (2) to penetrate the second lid member. It extends outward from 250.

As shown in FIGS. 1 to 3, the HMT unit 1 according to the present embodiment is mounted on one side of the mission case 510 in the vehicle width direction, and the rotational power from a drive source (not shown) is described above. It is transmitted to the other side of the mission case 510 in the vehicle width direction.

Therefore, the power transmission from the drive source to the input shaft 310 is a drive shaft 320 arranged coaxially with the input shaft 310, and one end side is connected to the input shaft 310 in a relative rotation around the axis and the other. This is done via a drive shaft 320 whose end side extends to the other side of the mission case 510 in the vehicle width direction.
The drive shaft 320 is interpolated and supported by a shaft case 515 connected to the mission case 510 so as to be rotatable around an axis, and one end side supports an input pulley outside the shaft case 515 and is supported by another. The end side is connected to the input shaft 310 via the first coupling 320a.

The constant speed transmission unit 330 has an input transmission gear 335 that operates and transmits rotational power from the input shaft 310 to the constant speed input element.

In the present embodiment, the internal gear 130 acts as the constant speed input element, the sun gear 110 acts as a speed change input element by being supported by the motor shaft so as not to rotate relative to the motor shaft, and the carrier 150 acts as the shift input element. It acts as an output element that outputs synthetic rotational power.

In this case, the input transmission gear 335 operates and transmits constant speed rotational power from the input shaft 310 to the internal gear 130.
In the present embodiment, as shown in FIG. 3 and the like, the input transmission gear 335a is supported in the second chamber 200 (2) so as to be non-rotatably supported by the input shaft 310. And the second input transmission gear 335a supported by the intermediate shaft 336 so as to mesh with the first input transmission gear 335a and the internal gear 130.

The output shaft 350 is configured so that the other side in the first direction extends outward from the second lid member 250 and acts as an output unit in a state of being operatively connected to the output element.

In the present embodiment, as shown in FIG. 3 and the like, the planetary gear mechanism 100 is in a state where the output shaft 350 is operatively connected to the carrier 150 that acts as an output element via an output side transmission unit 370. It is displaced in the radial direction from the axial position of.

The output-side transmission unit 370 has an output-side transmission shaft 371 coaxially connected to the carrier 150 so as not to rotate relative to the carrier 150, and an output supported by the output-side transmission shaft 371 so as to be relatively non-rotatable. The output side that is non-rotatably supported by the portion of the output shaft 350 located in the second chamber 200 (2) in a state of being meshed with the side first transmission gear 373 and the output side first transmission gear 373. It has a second transmission gear 375.

In the present embodiment, the output side second transmission gear 375 has a smaller diameter than the output side first transmission gear 373 so that the rotational power is transmitted from the output element to the output shaft 350 at an accelerated speed. There is.

The output side transmission shaft 371 is detachably connected to the carrier 150 via a spline connection.
Specifically, as shown in FIG. 5, the second carrier main body 170 (2) extends in the radial direction with reference to the axis of the planetary gear mechanism 100, and the second end portion 162 (2) of the carrier pin 160. It has a radial extending portion 180 (2) and a hollow tubular portion 185 (2) extending in the axial direction from the radial inner end portion of the radial extending portion 180 (2).

A spline is formed on the inner peripheral surface of the tubular portion 185 (2), and a spline that meshes with the spline is formed on the outer peripheral surface of the connecting end portion of the output side transmission shaft 371.

In the present embodiment, as shown in FIGS. 3 to 5, the housing body 210 is provided with a support wall 255 so as to be located on the joint surface of the housing body 210 with the second lid member 250. The tubular portion 185 (2) of the second carrier main body 170 (2) is supported by the support wall 255 via a bearing member 256.

One end side of the output side transmission shaft 371 is inserted into the tubular portion 185 (2) of the second carrier main body 170 (2), and the other end side is supported by the second lid member 250.

The first carrier main body 170 (1) also extends in the radial direction with reference to the axis of the planetary gear mechanism 100, and extends in the radial direction to support the first end portion 162 (1) of the carrier pin 160. It has 180 (1) and a hollow tubular portion 185 (1) extending in the axial direction from the radial inner end portion of the radial extending portion 180 (1).

The radial extending portion 180 (1) of the first carrier main body 170 (1) has a central opening communicating with the axial hole of the tubular portion 185 (1) at the center in the radial direction, and the motor. The shaft 30 penetrates the axial hole of the tubular portion 185 (1) and the central opening of the radial extending portion 180 (1), and reaches the other side in the axial direction from the first carrier main body 170 (1). There is.
The sun gear 110 is spline-connected to the other side of the motor shaft 30 in the axial direction.

As shown in FIG. 3 and the like, the bearing member 261 and the seal member 262 are arranged in the support hole supporting the input shaft 310 in the second lid member 250, and the support hole supporting the output shaft 350 is sealed. A functional bearing member 265 is arranged, whereby the second chamber 200 (2) is liquid-tightly partitioned with respect to the outside.
Reference numeral 205 in FIG. 4 is the oil level of the oil stored in the second chamber 200 (2).

As shown in FIG. 3 and the like, the HMT unit 1 according to the present embodiment further includes a charge pump unit 80 for supplying hydraulic oil to the HST 10.

Specifically, one end side of the pump shaft 20 in the axial direction extends outward from the first lid member 230.
The charge pump unit 80 is a charge pump case mounted on the first lid member 230 so as to surround the charge pump main body 81 supported by the outward extending portion of the pump shaft 20 and the charge pump main body 81. It has 83 and.

Embodiment 2
Hereinafter, other embodiments of the HMT unit according to the present invention will be described with reference to the accompanying drawings.
FIG. 9 shows a developed sectional view of a state in which the HMT unit 2 according to the present embodiment is mounted on the transmission 500.
FIG. 10 shows a disassembled and developed cross-sectional view of the HMT unit 2 separated from the transmission 500.
Further, FIG. 11 shows an enlarged cross-sectional view of the planetary gear mechanism 100 in the HMT unit 2.
In the figure, the same members as those in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted as appropriate.

In the HMT unit 2 according to the present embodiment, the constant speed transmission unit 330 is changed to the constant speed transmission unit 430, and the output shaft 350 is arranged coaxially with the planetary gear mechanism 100. In that respect, it differs from the HMT unit 1 according to the first embodiment.

As shown in FIGS. 9 and 10, the constant speed transmission unit 430 is supported by the input shaft 310 so as not to rotate relative to the input shaft 310, and is meshed with the internal gear 130 that acts as a constant speed input element. have.
In the illustrated form, the input transmission gear 435 is integrally formed with the input shaft 310.

As shown in FIGS. 9 to 11, in the output shaft 350, one end side in the axial direction is spline-connected to the tubular portion 185 (2) of the second carrier main body 170 (2), and the other end side in the axial direction is the second lid. It extends outward from the member 250.

In the present embodiment, as shown in FIG. 11, in order to prevent the stored oil from leaking from the second chamber 200 (2), the tubular portion of the second carrier main body 170 (2) A seal cap 270 is provided in the shaft hole of 185 (2).

Further, the second lid member 250 is provided with a bearing hole through which the tubular portion 185 (2) is penetrated, and a bearing with a sealing function for supporting the tubular portion 185 (2) in the bearing hole. A member 265 is provided.

In the first and second embodiments, the drive shaft 320 is housed in the shaft case 515 connected to the mission case 510, but the drive shaft 320 can also be housed in the mission case 511. Is.

12 and 13, respectively, show a perspective view and a developed sectional view of a state in which the HMT unit 2 according to the second embodiment is connected to a transmission 501 including a transmission case 511 accommodating the drive shaft 320. ..
Further, FIG. 14 shows an exploded sectional view of FIG. 13.
In the figure, the same members as those in the first and second embodiments are designated by the same reference numerals.

In the modified examples shown in FIGS. 12 to 14, the transmission case 511 of the transmission 501 includes the drive shaft 320 for operatively inputting rotational power from the drive source, the transmission input shaft 505, and the HMT unit. The first coupling 320a that connects the drive shaft 320 to the input shaft 310 by connecting the housing 200 to the transmission case 511, and the output shaft 350 by connecting the housing 200 to the transmission case 511. A second coupling 530a connected to the transmission input shaft 505 is provided.

In the modified example shown in FIGS. 12 to 14, the first unevenness is arranged coaxially with the drive shaft 320 and the input shaft 310 at the contact portions of the housing 200 of the HMT unit 2 and the transmission case 511. An engagement structure and a second uneven engagement structure arranged coaxially with the output shaft 350 and the transmission input shaft 505 are provided, whereby when the housing 200 is connected to the transmission case 511. The drive shaft 320 and the input shaft 310, and the output shaft 350 and the transmission input shaft 505 can be reliably aligned.

15 (a) shows an enlarged exploded view of the vicinity of the contact portion between the housing 200 and the mission case 511 in the modified examples shown in FIGS. 12 to 14.

As shown in FIG. 15A, in the modified example, the housing 200 of the HMT unit 2 has a contact surface with respect to the mission case 511, and the side of the mission case 511 coaxially with the input shaft 320. A first convex portion 291a projecting to the side of the mission case 511 and a second convex portion 292a projecting to the side of the mission case 511 on the same axis as the output shaft 350 are provided.

On the other hand, in the mission case 511, the first convex portion 291a can be engaged with the contact surface of the HMT unit 2 with respect to the housing 200, and the first concave-convex engagement structure is formed together with the first convex portion 291a. A first concave portion 291b to be formed and a second concave portion 292b to which the second convex portion 292a can be engaged and which forms the second concave-convex engaging structure together with the second convex portion 292a are provided.

In the modification, the first and second convex portions are formed by the first and second convex portion forming members 272 and 273, which are detachably attached to the housing 200, respectively.
In the modified example, the first and second convex portion forming members 272 and 273 support the seal member 262 and the output shaft 350 arranged in the support holes that support the input shaft 310, respectively. It also acts as a stopper for the seal member 263 arranged in the support hole.

In this way, the housing 200 of the HMT unit 2 is connected to the transmission case 511 by providing the first and second uneven engagement structures at the contact portions of the housing 200 of the HMT unit 2 and the transmission case 511. When this is done, the alignment of the drive shaft 320 and the input shaft 320, and the alignment of the output shaft 350 and the transmission input shaft 505 can be reliably performed.
Reference numerals 296 and 297 in FIG. 15A are seal rings.

In the modified examples shown in FIGS. 12 to 14, the first and second convex portions 291a and 292a in the first and second concave-convex engagement structures are provided in the housing 200 of the HMT unit 2, and the first and second concave portions are provided. Although 291b and 292b are provided in the mission case 511, the present invention is not limited to such a form.

That is, as shown in FIG. 15B, first and second convex portions 291a and 292a are provided on the contact surface with the housing 200 in the mission case 511, and the first and second concave portions 291b are provided in the housing 200. , 292b can also be provided.

In the example shown in FIG. 15B, the first and second convex portion forming members 272B and 273B are mounted on the contact surface with the housing 200 in the mission case 511, and the first and second convex portions are attached. The portion forming members 272B and 273B form the first and second convex portions, respectively.
The first and second convex portion forming members 272B and 273B are configured to prevent the seal members 262 and 263 from coming off in a state where the housing 200 and the mission case 511 are connected to each other.
Reference numerals 276 and 277 in FIG. 15B are positioning pins for aligning the first and second convex portion forming members 272B and 273B with respect to the mission case 511.

Further, one of the first and second convex portions 291a and 292a is provided in the housing 200, the corresponding concave portion is provided in the mission case 511, and the other of the first and second convex portions 291a and 292a is provided. In addition to being provided in the mission case 511, it is also possible to provide a corresponding recess in the housing 200.

In FIG. 15C, the first convex portion 291a is provided in the housing 200 by mounting the first convex portion forming member 272 on the housing 200, and the corresponding first concave portion 291b is provided in the mission case 511. The second convex portion 292a is provided in the mission case 511 by mounting the second convex portion forming member 273B on the mission case 511, and the corresponding second concave portion 292b is provided in the housing 200. The modified configuration is shown.

Also in the configurations shown in FIGS. 15 (b) and 15 (c), when the housing 200 of the HMT unit 2 is connected to the transmission case 511, the drive shaft 320 and the input shaft 310 are aligned, and the above. The output shaft 350 and the transmission input shaft 505 can be reliably aligned.

In addition, in FIGS. 12 to 14 and 15 (a) to 15 (c), the HMT unit 2 according to the second embodiment is connected to the transmission 501, but of course, the first embodiment It is also possible to connect the HMT unit 1 to the transmission 501.

In the present embodiment, the input shaft 310 is configured to extend outward from the second lid member 250 and input the rotational power from the drive source from the side of the second lid member 250. However, instead of this, it is also possible to configure so that the rotational power from the drive source is input from the side of the first lid member 230.

FIG. 16 shows a longitudinal development view of the HMT unit 2'deformed so that the rotational power from the drive source is input from the side of the first lid member 230.
In the figure, the same members as those in the second embodiment are designated by the same reference numerals, and the description thereof will be omitted as appropriate.

As shown in FIG. 16, in the modified example, one side of the pump shaft 20B extends outward from the first lid member 230 to form the input shaft, and the other side in the axial direction is the second. It is supported by the first lid member 230 and the partition wall 225 in a state of being plunged into the chamber 200 (2).

The motor shaft 30 has the first lid member 230 and the partition wall 225 in a state where the motor shaft 30 is along the first direction and the other side of the first direction is inserted into the second chamber 200 (2), as in the second embodiment. Supported by.

In the modification, the constant speed transmission unit 430B is configured to operate and transmit rotational power from the pump shaft 20B to the constant speed input element.

Specifically, in the modified example, the constant speed transmission unit 430B is spline-connected to the portion of the pump shaft 20B whose one end side is rushed into the second chamber 200 (2), and the other end side is the first side. 2 The input transmission shaft 431B supported by the lid member 250 and the input transmission gear 435B meshed with the internal gear 130 which is supported by the input transmission shaft 431B so as to be relatively non-rotatable and acts as the constant speed input element. Have.
In the illustrated embodiment, the input transmission gear 435B is integrally formed with the input transmission shaft 431B.

Of course, the modified configuration in which the rotational power from the drive source is input from the side of the first lid member 230 can also be applied to the first embodiment.

Further, in the first and second embodiments and the embodiments shown in FIGS. 12 to 14, the connecting ends of the input shaft 310 and the output shaft 350 are moved outward from the housing 200 (the second lid member 250). Although the configuration is extended, instead of this, the connecting end portion of the input shaft 310 and / or the output shaft 350 is arranged inside the end surface of the housing 200 (the second lid member 250). It is also possible to have a coupling structure with splines.

In the first and second embodiments and the embodiments shown in FIGS. 12 to 14, the first coupling 320a is provided in the shaft case 515 or the mission case 511, and the second coupling 530a is the mission case 510. Although it is provided in 511, it is also possible to provide one or both of the first coupling 320a and the second coupling 530a in the housing 200.

1, 2, 2'HMT unit 10 HST
20 Pump shaft 25 Hydraulic pump 30 Motor shaft 35 Hydraulic motor 40 (P) Pump side volume change member 40 (M) Motor side volume change member 100 Planetary gear mechanism 110 Sun gear 120 Planet gear 130 Internal gear 150 Carrier 200 Housing 200 (1) ) First chamber 200 (2) Second chamber 210 Housing body 220 Peripheral wall 221 First opening 222 Second opening 225 Partition 230 First lid member 250 Second lid member 310 Input shaft 320 Drive shaft 320a First coupling 330, 430 430B Constant speed transmission 350 Output shaft 500, 501 Transmission 505 Transmission input shaft 510, 511 Transmission case 530a Second coupling

Claims (6)

The planetary gear mechanism includes an HST that continuously shifts and outputs the rotational power input from the drive source, and a planetary gear mechanism that synthesizes and outputs the rotational power from the drive source and the rotational power from the HST. Supports the sun gear that is actuated and connected to the motor shaft of the HST, the planetary gear that meshes with the sun gear, the internal gear that meshes with the planetary gear, and the planetary gear that can rotate around the axis and the planetary gear. An HMT unit having a carrier that rotates around the axis of the sun gear in conjunction with the revolution around the sun gear.
A housing that is detachably connected to a mounting location while accommodating the HST and the planetary gear mechanism is provided.
The HST includes a pump shaft, a hydraulic pump supported by the pump shaft, a hydraulic motor fluidly connected to the hydraulic pump, the motor shaft supporting the hydraulic motor, and the hydraulic pump and the hydraulic motor. It has a volume changing member that changes the volume of at least one of them,
The housing, before forming an input shaft for inputting a rotational power from said driving source in a state of integrally rotating the Kipo pump axis and about the axis, the rotational power of the input shaft by one of said internal gear and the carrier A constant speed transmission unit that transmits the operation to the constant speed input element and an output shaft that outputs the combined rotational power of the output element formed by the internal gear and the other of the carriers to the outside are provided .
The housing divides the internal space of the peripheral wall into a first chamber and a second chamber at a position intermediate between the hollow peripheral wall having the first and second openings on one side and the other side in the first direction and the peripheral wall in the first direction. A housing body having a partition wall, a first lid member detachably connected to the housing body so as to close the first opening, and a detachably connected to the housing body so as to close the second opening. Has a second lid member to be
The hydraulic pump, the hydraulic motor, and the volume changing member are housed in the first chamber, and the planetary gear mechanism is housed in the second room.
The pump shaft is in a state in which one side in the first direction extends outward from the first lid member to form the input shaft along the first direction and the other side in the first direction plunges into the second chamber. Supported by the first lid member and the partition wall,
The motor shaft is supported by the first lid member and the partition wall along the first direction and with the other side in the first direction plunging into the second chamber.
The constant speed transmission unit is configured to operate and transmit rotational power from the pump shaft to the constant speed input element.
The output shaft is in a state of being operatively connected to the output element, HMT unit first direction other side which is characterized that you act as an output unit is extended outward from the second lid member. The HMT unit according to claim 1 , wherein the combined rotational power is continuously changed between the maximum speed in the reverse rotation direction and the maximum speed in the forward rotation direction by operating the volume changing member. The HMT unit according to claim 1 or 2 , wherein the first lid member is formed with a pair of hydraulic oil passages for fluidly connecting the hydraulic pump and the hydraulic motor. A planetary gear that synthesizes and outputs the HST that outputs the rotational power input from the drive source in a stepless manner, the rotational power from the drive source, and the rotational power that is operatively input to the sun gear from the motor shaft of the HST. An HMT unit having a mechanism and a housing for accommodating the HST and the planetary gear mechanism.
A transmission having a transmission case to which the housing is detachably connected is provided.
The housing has an input shaft operatively connected to the pump shaft of the HST and a constant speed transmission in which the input shaft is operatively connected to a constant speed input element formed by one of the internal gear and the carrier of the planetary gear mechanism. The unit and the output shaft that outputs the combined rotational power of the output element formed by the internal gear and the other of the carriers to the outside are juxtaposed.
The transmission case is provided with a drive shaft for operatively inputting rotational power from the drive source and a transmission input shaft.
By connecting the housing to the transmission case, the drive shaft is connected to the input shaft via the first coupling, and the output shaft is connected to the transmission input shaft via the second coupling. Characterized HMT structure. The HMT structure according to claim 4 , wherein the first coupling and the second coupling are provided in the mission case. The HST includes the pump shaft, a hydraulic pump supported by the pump shaft, a hydraulic motor fluidly connected to the hydraulic pump, the motor shaft supporting the hydraulic motor, the hydraulic pump, and the hydraulic motor. Has a volume changing member that changes the volume of at least one of the
In the HST and the planetary gear mechanism, the rotational speed of the motor shaft is changed by the operation of the volume changing member, so that the combined rotational power output from the output shaft is the maximum speed in the reverse rotation direction and the maximum speed in the forward rotation direction. The HMT structure according to claim 4 or 5 , wherein the HMT structure is set so as to continuously change gears with and from.

Images