JP6672560B2 - Hydraulic pump unit for clutch hydraulic oil supply - Google Patents

Description

  The present invention relates to a hydraulic pump unit, and more particularly to a hydraulic pump unit used for supplying hydraulic oil to a hydraulic clutch of a dual clutch type transmission.

  DESCRIPTION OF RELATED ART Conventionally, as disclosed in patent document 1, the carrier provided with the dual clutch type transmission, so-called utility vehicle is known. A dual-clutch transmission is a transmission case in which an odd-numbered (first speed, third-speed, etc.) gear train group including at least one odd-speed gear train, and an even-numbered gear (including the at least one even-speed gear train) A second clutch, a fourth gear, etc.) gear train, a first clutch used for connecting / disconnecting power transmission via an odd-speed gear train selected from the odd-number gear train, and the even-number gear train A second clutch used for connecting / disconnecting power transmission via a selected even-numbered gear train is internally provided, and the first clutch and the second clutch are alternately engaged and disengaged. (That is, when one engages, the other moves away), the power is transmitted seamlessly, and a smooth gear change such as from the first speed to the second speed and from the second speed to the third speed is achieved. realizable. In particular, during the transition between engagement and disengagement between the first clutch and the second clutch, both the clutches are in the half-clutch state, thereby enabling a smooth gear shift.

  As such first and second clutches, hydraulic clutches that are likely to exhibit a half-clutch state are used. Further, the dual clutch type transmission disclosed in Patent Literature 1 includes a dual hydraulic pump. The two hydraulic pumps constituting the dual hydraulic pump are driven simultaneously by an engine which is a drive source of a dual clutch type transmission, and the discharge oil from one of these hydraulic pumps is the first hydraulic pump. It is supplied as hydraulic oil for the second clutch, hydraulic oil for the gear shifter switching actuator, and also as lubricating oil for each part. The discharge oil from the other hydraulic pump is supplied for other uses.

  The hydraulic pump (one of the dual hydraulic pumps) used for supplying hydraulic clutch hydraulic oil (hydraulic oil system) and supplying lubricating oil for each part (lubricating oil system) in Patent Document 1 has an engine speed. Therefore, the discharge amount increases in proportion to the above, and a large capacity is required. On the other hand, the amount of oil required for the lubricating oil system is defined by the relief pressure of the relief valve and the like, and does not increase in proportion to the engine speed. For this reason, when the engine rotates at high speed, most of the amount of oil discharged from the hydraulic pump is discharged in excess of the amount required as lubricating oil, resulting in a large energy loss and a reduction in the running economy of the vehicle. Not preferred.

  Then, in order to be able to adjust the discharge amount without such energy loss, it is conceivable to use a variable displacement hydraulic pump as the hydraulic pump for the hydraulic oil system and the lubricating oil system as described above. For example, in Patent Document 2, as such a variable displacement type hydraulic pump for a hydraulic oil system and a lubricating oil system, a vane pump capable of adjusting the eccentric amount of a cam ring by hydraulic control to adjust the discharge oil amount is used. I have.

JP 2008-309325 A JP-A-2-283958

  However, the above-described variable displacement hydraulic pump requires a hydraulic circuit for controlling the amount of discharged oil in addition to a hydraulic circuit for suction and discharge of the pump. This complicates the structure and tends to increase the manufacturing cost.

  SUMMARY OF THE INVENTION The present invention, as a hydraulic pump unit for supplying hydraulic oil to a hydraulic clutch as used in a dual clutch transmission, consumes as much energy as possible during high-speed rotation of an engine as a power source in view of the above circumstances. It is an object of the present invention to provide a hydraulic pump having a simple and low-cost structure capable of minimizing the amount of work performed by a hydraulic pump so as not to cause the problem.

The present invention is a hydraulic pump unit for supplying clutch hydraulic oil, which is a combination of a dual first hydraulic pump and a second hydraulic pump driven simultaneously by a power source, and a first chamber formed in a main housing, A second chamber formed by the main housing and a lid closing an opening of the main housing, the second chamber being adjacent to the first chamber via a partition, and the first hydraulic pump and the second chamber are provided in the first chamber. The second hydraulic pump is housed in the second chamber, and a hydraulic clutch is housed in the second chamber. In order to achieve the above object, the following technical means are used.

That is, the hydraulic pump unit clutch hydraulic oil feed according to the present invention, with respect to the hydraulic oil chamber of the hydraulic clutch, irrespective of the rotational speed of the animal power source, the oil passage bored with the main housing to the cover And supplying the discharge oil from the first hydraulic pump through the main housing and the lid when the rotation speed of the power source is less than a predetermined value. Through the oil passage, and merges with the discharge oil from the first hydraulic pump. When the rotation speed of the power source is equal to or higher than a predetermined value, the discharge oil from the second hydraulic pump is supplied to the main housing and the lid. The first hydraulic pump is configured to return to a suction port of the first hydraulic pump via an oil passage formed in the body .

  Further, the hydraulic pump unit is extended from a discharge port of the first hydraulic pump, a hydraulic oil supply oil passage toward a hydraulic oil chamber of a hydraulic clutch, and a controller based on detection of a rotation speed of the power source. An on-off valve that is controlled to open and close, a communication oil passage that connects a discharge port of the second hydraulic pump and the hydraulic oil supply oil passage to an inlet port of the on-off valve, and an outlet port of the on-off valve that connects the second hydraulic pump And a suction oil passage communicating between the suction ports of the first hydraulic pump and the second hydraulic pump. The on-off valve is closed when the number of revolutions of the power source is less than a predetermined value, and the oil from the discharge port of the second hydraulic pump is supplied to the hydraulic oil supply oil path via the communication oil path. To join. The on-off valve is opened when the number of revolutions of the power source is equal to or higher than a predetermined value, and the oil from the discharge port of the second hydraulic pump to the communication oil passage is discharged from the inlet port to the outlet port. Through the return oil passage, the suction port of the second hydraulic pump, and the suction oil passage to the suction port of the first hydraulic pump.

  Further, a check valve that allows only an oil flow from the communication oil passage to the hydraulic oil supply oil passage when the on-off valve is closed is provided between the communication oil passage and the hydraulic oil supply oil passage. Provided.

  As described above, the clutch hydraulic oil supply hydraulic pump unit according to the present invention supplies the discharge oil from both the first and second hydraulic pumps to the hydraulic oil supply oil passage when the rotation speed of the power source is less than a predetermined value. By feeding, the supply amount of hydraulic oil required for operating the hydraulic clutch and the supply amount of lubricating oil required for a transmission mechanism such as a dual clutch type transmission are secured, while the rotational speed of the power source is secured. Is supplied to the hydraulic clutch only at the time of high-speed rotation of the power source, which is a region equal to or more than a predetermined value, so that the amount of discharged oil is not excessive and is used for driving the hydraulic pump. Energy can be minimized. As described above, the fuel consumption can be improved by reducing the energy used for driving the hydraulic pump.

  Further, by configuring the hydraulic oil supply oil passage, the communication oil passage, the return oil passage, and the suction oil passage as described above, the hydraulic oil according to the rotation speed of the power source by the first and second hydraulic pumps as described above. Supply system can be realized. Such a hydraulic oil supply oil passage, a communication oil passage, a return oil passage, and a suction oil passage can be integrated around the first and second hydraulic pumps and the on-off valve to constitute a hydraulic pump unit. The compactness of the pump unit can be ensured.

  Further, by providing the check valve as described above, it is possible to prevent the discharge oil from the first hydraulic pump from leaking into the communication oil passage with a simple configuration, and to reliably switch the oil amount.

1 is a schematic side view of a transport vehicle as an example of a work vehicle including a dual clutch transmission. 2 is a schematic plan view of the carrier. It is a skeleton diagram of a dual clutch type transmission. FIG. 3 is a hydraulic circuit diagram showing a hydraulic oil supply system to hydraulic clutch units as first and second clutches in the dual clutch transmission. It is a front view of a dual clutch type transmission. FIG. 3 is a front view of the dual clutch type transmission, showing a layout of gears in a clutch chamber with a lid removed. Fig. 4 is a partial front sectional view of a lid removed from a housing of the dual clutch type transmission. Fig. 2 is a schematic front sectional view of the dual clutch type transmission showing a layout of gears in a gear chamber. FIG. 9 is a developed sectional view of the dual clutch type transmission shown by the XL line in FIG. 8. FIG. 10 is an enlarged sectional view of a hydraulic clutch unit as a first clutch in the dual clutch transmission shown in FIG. 9. It is a perspective view of the lubricating oil guide plate used for the hydraulic clutch unit shown in FIG. FIG. 3 is a partial side sectional view of the dual clutch transmission showing an oil passage structure of a hydraulic pump unit and a transmission case arranged in the gear chamber. It is a partial side sectional view of another form of a dual clutch type transmission in which a hydraulic pump unit is arranged in the clutch chamber. FIG. 14 is a correlation diagram of the pump discharge amount with respect to the engine speed showing the effect of reducing the discharge oil amount using the hydraulic pump unit shown in FIG. 12 or 13.

  The carrier (so-called utility vehicle) 100 shown in FIGS. 1 and 2 will be described. The transport vehicle 100 includes a vehicle frame (chassis) 101 extending in a front-rear direction from a front end to a rear end. At the rear of the vehicle frame 101, left and right rear wheels 110 are suspended via respective suspensions 119, while at the front of the vehicle frame 101, left and right front wheels 120 are suspended via respective suspensions 128. Have been.

  At the rear of the vehicle frame 101, a carrier mounting frame 102 is formed. In the carrier mounting frame 102, the vehicle frame 101 supports an engine E having a front-rear direction crankshaft.

  A carrier 107 is mounted on the carrier mounting frame 102 so as to be rotatable upward. Normally, it rotates upward as shown by the imaginary line in FIG. 1 for unloading and the like. However, when it is desired to access the engine E for maintenance or the like, it is necessary to rotate the loading platform 107 in this manner. Thus, the engine E disposed below is opened and accessible.

  A seat base 103 is formed at the front of the carrier mounting frame 102, and a seat 108 is mounted on the seat base 103 as described later. Immediately before the seat base 103, a platform 104 is laid on the body frame 101, and serves as a footboard for a person who is getting on and off the carrier 100 and sitting on the seat 108.

  A hood 105 is provided at the front of the body frame 101 in front of the platform 104, and a front column 106 is formed at the rear end of the hood 105. A steering handle 109 is provided above the front column 106. .

  The dual clutch transmission 1 is arranged in a space covered by the seat 103 and is supported by the vehicle frame 101. A horizontal engine output shaft Ea protrudes forward from the engine E, and a flywheel Eb is provided at a front end of the engine output shaft Ea.

  The dual clutch type transmission 1 arranged in front of the engine E has a transmission case 2 as a housing. A rear open flywheel chamber 2a is formed in a rear portion of the transmission case 2, and a flywheel Eb of the engine E is disposed in the flywheel chamber 2a.

  The dual-clutch transmission 1 includes a gear mechanism and a clutch mechanism for shifting and traveling direction switching, which will be described later, housed in a transmission case 2, and a power input to the gear mechanism and the clutch mechanism. The rear end of the input shaft 7 extends into the flywheel chamber 2a and is connected to the flywheel Eb.

  A seat 108 is mounted on a seat mounting plate 103a constituting the horizontal upper surface of the seat base 103. In the present embodiment, a pair of left and right seats 108 are provided as a driver's seat and a passenger seat. As described above, the dual clutch type transmission arranged in the space in the seat base 103 is arranged below the seat 108 mounted on the seat mounting plate 103a.

  The seat mounting plate 103a is rotatable forward along with the seat 108, as indicated by a virtual line in FIG. That is, the seat 108 is rotatably mounted on the seat base 103 via the seat mounting plate 103a, and is surrounded by the seat base 103 by rotating the seat 108 forward with the seat mounting plate 103a. The opened space is opened upward, and access to the dual clutch transmission 1 is enabled.

  A flywheel housing 3 having the flywheel chamber 2a formed therein is connected to a rear portion of the main housing 4, and a lid 5 is attached to a front portion of the main housing 4 so that the front and rear flywheel housings 3 are joined. , The main housing 4 and the lid 5 constitute the transmission case 2 of the dual clutch transmission 1 described above.

  Since the lid 5 is detachably attached to the main housing 4 at the front end of the transmission case 2, the seat mounting plate 103 a and the seat 108 are rotated forward as described above to rotate the dual clutch type. When the transmission 1 is accessed, the cover 5 can be removed from the main housing 4 to open a clutch chamber 2c, which will be described later, formed in the front portion of the transmission case 2 forward. The first and second clutches 21 and 31 can be easily accessed.

  A rear axle drive device 112 for driving a rear wheel 110 is supported at a rear portion of the body frame 101. The rear axle drive device 112 has a rear axle drive case 113, and accommodates a conventional bevel gear type differential gear mechanism 116 in the rear axle drive case 113.

  The differential gear mechanism 116 connects the inner ends of the pair of left and right differential output shafts 117 so as to be rotatable in a differential manner, and the outer end of each differential output shaft 117 is located right and left with respect to the rear axle drive case 113. Each of the wheels protrudes outward and is connected to an axle 110a of each rear wheel 110 via a transmission shaft 118 with a universal joint.

  The rear axle drive device 112 has an input shaft 114 in the front-rear horizontal direction. The input shaft 114 is pivotally supported by a rear axle drive case 113, and its front end protrudes from the rear axle drive case 113. On the other hand, in the dual clutch type transmission 1, the transmission case 2 (main housing 4) supports the front and rear horizontal output shaft 12, and the rear end of the output shaft 12 is connected to the rear outside of the transmission case 2. And is connected to the input shaft 114 of the rear axle drive device 112.

  The input shaft 114 is arranged on the same axis as the output shaft 12. Between the rear end of the output shaft 12 and the front end of the input shaft 114, a transmission shaft 111 in the front-rear horizontal direction is provided on the same shaft center, and couplings 111a and 111b formed of spline cylinders or the like are provided. , The front end of the transmission shaft 111 is connected to the rear end of the output shaft 12, the rear end of the transmission shaft 111 is connected to the front end of the input shaft 114, and the output shaft 12, the transmission shaft 111, and the input The shaft 114 is connected so as to be rotatable integrally (relative rotation is impossible). With such a coupling structure from the output shaft 12 to the input shaft 114 on the same axis, a high transmission efficiency from the output shaft 12 to the rear wheel 110 is ensured, and the driving efficiency of the rear wheel 110 is enhanced.

  In addition, the support position of the output shaft 12 in the transmission case 2 (the main housing 4) is slightly biased (rightward in the present embodiment) from the left and right center in the left and right direction of the transport vehicle 100. On the other hand, the differential gear mechanism 116 in the rear axle drive device 112 is disposed substantially at the center on the left and right of the transport vehicle 100 so that the distance in the left and right direction to each of the left and right rear wheels 110 is equal.

  Therefore, the input shaft 114 arranged on the same axis as the output shaft 12 of the dual clutch transmission 1 is offset from the differential gear mechanism 116 in the left-right direction. The left and right horizontal counter shafts 115 are supported in the front part of the rear axle drive case 113 (in front of the differential gear mechanism 115) so as to compensate for the positional deviation in the left and right direction.

  In the rear axle drive case 113, a bevel gear 115a is fixed (or formed) at one end (right end in this embodiment) of the counter shaft 115, and is fixed (or formed) at the rear end of the input shaft 114. ) Is engaged with the bevel gear 114a. On the other hand, a flat gear 115b is fixed (or formed) at the other end (the left end in this embodiment) of the counter shaft 115, and meshes with a flat gear as an input gear 116a of the differential gear mechanism 116. ing.

  At the front of the body frame 101, a rear axle drive device 122 for driving the front wheels 120 is supported. The front axle drive device 122 has a front axle drive case 123 and houses a conventional bevel gear type differential gear mechanism 125 in the front axle drive case 123.

  The differential gear mechanism 125 connects the inner ends of the pair of left and right differential output shafts 126 to be rotatable in a differential manner. Each protrudes outward and is connected to the axle 120a of each front wheel 120 via a transmission shaft 127 with a universal joint.

  The left and right front wheels 120 are steering wheels. The two front wheels 120 are connected to each other by a tie rod 129, and the tie rod 129 moves left and right in response to the turning operation of the steering handle 109, so that both the front wheels 120 move right and left simultaneously. It turns, and the transport vehicle 100 turns.

  The front axle drive device 122 has an input shaft 124 in the front-rear horizontal direction. The input shaft 124 is rotatably supported at the rear of the rear axle drive case 123, and a bevel gear 124 a fixed (or formed) at the front end of the input shaft 124 in the front axle drive case 123 is connected to a differential gear mechanism. 125 is engaged with a bevel gear as an input gear 125a.

  The rear end of the input shaft 124 projects rearward from the front axle drive case 123. On the other hand, in the dual clutch transmission 1, the front end of the output shaft 12 is in front of the transmission case 2 (main housing 4). It is projected outside. A transmission shaft 121 is provided between the front end of the output shaft 12 and the front end of the input shaft 124, and the rear end of the transmission shaft 121 is connected to the front end of the output shaft 12 via universal joints 121 a and 121 b. The front end of the transmission shaft 121 is connected to the rear end of the input shaft 124.

  The input shaft 124 of the front axle drive device 122 and the differential gear mechanism 125 are disposed substantially at the center on the left and right of the transport vehicle 100, while the output shaft 12 of the dual clutch transmission 1 is connected to the left and right of the transport vehicle 100 as described above. The transmission shaft 121 interposed between the output shaft 12 and the input shaft 124 is inclined left and right because it is slightly shifted to one side (the right side in this embodiment), and the universal joints 121a and 121b Power transmission from the output shaft 12 to the input shaft 124 via the inclined transmission shaft 121 is ensured.

  Next, a power transmission system from the input shaft 7 to the output shaft 12 included in the dual clutch transmission 1 will be described with reference to the skeleton diagram of FIG. 3 and the structural diagram of FIG.

  The dual-clutch transmission 1 includes a front-rear horizontal input shaft 7 disposed on the same axis as an output shaft Ea of the engine E, a front-rear horizontal output shaft 12 parallel to the input shaft 7, and a parallel output shaft 12. It has a first clutch shaft 8, a second clutch shaft 9, a shift driven shaft 10, and a counter shaft 11 in the front-rear horizontal direction.

  The input shaft 7 is connected to the engine output shaft Ea via the flywheel Eb as described above. An input gear 7a, which is a spur gear, is fixedly (or formed) to the input shaft 7, and a first clutch gear 20, which is a spur gear loosely fitted to the first clutch shaft 8, is attached to the input gear 7a. The second clutch gear 30, which is a flat gear loosely fitted to the two-clutch shaft 9, is engaged. Thus, the first clutch gear 20 and the second clutch gear 30 are both meshed with the input gear 7a, but the first clutch gear 20 and the second clutch gear 30 are not meshed with each other.

  As for the engine E, which is the power source of the dual clutch type transmission 1, there are several different types of engine (e.g., gasoline engine or diesel engine) and specifications (e.g., displacement) prepared for the vehicle. The size of the input gear 7a and the first and second clutch gears 20 and 30 of the dual clutch type transmission 1 is changed in order to cope with the difference in the rotation speed of the engine output shaft Ea connected to the input shaft 7. By doing so, the gear ratio is adjusted.

  A first clutch 21 is provided on the first clutch shaft 8, and the power from the input shaft 7 received by the first clutch gear 20 is transmitted to the first clutch shaft 8 by engaging the first clutch 21. And On the other hand, a second clutch 31 is provided on the second clutch shaft 9, and the power from the input shaft 7 received by the second clutch gear 30 is transmitted to the second clutch shaft 9 by engaging the second clutch 31. Shall do.

  As described later, the clutch engagement pressure of the first and second clutches 21 and 31 is controlled by an electromagnetic proportional valve from zero to a predetermined pressure when the clutch is engaged, or from a predetermined pressure to zero when the clutch is disengaged. The hydraulic clutch unit 60, which is proportionally controlled, is used, so that a gradual clutch engagement state (a so-called half clutch) can be exhibited unlike the meshing clutch described later.

  The first clutch shaft 8 is provided with a first speed (lowest speed) drive gear 22, a third speed drive gear 24, and a fifth speed (highest speed) drive gear 26, each of which is provided on the shift driven shaft 10. The first speed (lowest speed) driven gear 23, the third speed driven gear 25, and the fifth speed driven gear 27 are directly meshed.

  Thus, the first speed (lowest speed) gear train G1a including the first speed drive gear 22 and the first speed driven gear 23, the third speed gear train G1b including the third speed drive gear 24 and the third speed driven gear 25, An odd-numbered gear train for transmitting power from the first clutch shaft 8 to the speed-change driven shaft 10 together with a fifth-speed (highest-speed) gear train G1c including a fifth-speed drive gear 26 and a fifth-speed driven gear 27. Group G1.

  As long as the first clutch 21 is engaged, via the gear train selected from the first, third, and fifth speed gear trains G1a, G1b, and G1c in the odd-numbered gear train group G1. Power is transmitted from the first clutch shaft 8 to the shift driven shaft 10. Shifters 28 and 29 are provided as members for selecting a gear train as a power transmission target from the odd-numbered gear train group G1.

  Here, in the first speed gear train G1a and the third gear train G1b, the first speed drive gear 22 and the third speed drive gear 24 are provided on the first clutch shaft 8 so as not to rotate relatively (in the present embodiment, As shown in FIG. 8, the first speed drive gear 22 is formed on the first clutch shaft 8, the third speed drive gear 24 is fixed to the first clutch shaft 8, and the first speed driven gear 23 and The third speed driven gear 25 is loosely fitted to the shift driven shaft 10 (which is rotatable relative to the shift driven shaft 10).

  In correspondence with the first and third speed gear trains G1a and G1b, the shifter 28 cannot rotate relative to the shift driven shaft 10 between the first speed driven gear 23 and the third speed driven gear 25. And it is provided so as to be slidable in the axial direction (front-back direction). Clutch teeth are formed on the first driven gear 23 and the third driven gear 25, respectively, and clutch teeth that can be engaged with the respective gears 23 and 25 are formed on each end face of the shifter 28. That is, the shift clutch 28 and the first speed driven gear 23 form a meshing clutch, and the shifter 28 and the third speed gear train 25 form a meshing clutch on the opposite side in the axial direction.

  The shifter 28 slides along the shift driven shaft 10 to shift to a first speed position where only the first speed driven gear 23 is engaged with the clutch, and a third speed position where only the third speed driven gear 25 is engaged with the clutch. Are switched to three neutral positions where neither the first driven gear 23 nor the third driven gear 25 is engaged.

  In the fifth speed gear train G1c, the fifth speed drive gear 26 is loosely fitted to the first clutch shaft 8 (relatively rotatable with respect to the first clutch shaft 8), and the fifth speed driven gear 27 is shifted. It cannot rotate relative to the driven shaft 10 (fixed to the shift driven shaft 10). In correspondence with such a fifth speed gear train G1c, a shifter 29 is provided on the first clutch shaft 8 so as to be relatively non-rotatable and slidable in the axial direction (front-rear direction). The fifth speed driven gear 26 and the shifter 29 are formed with clutch teeth so as to be engageable with each other, and the shifter 29 and the fifth speed driven gear 26 constitute a meshing clutch.

  The shifter 29 slides along the first clutch shaft 8 so that the shifter 29 slides along the first clutch shaft 8 into a fifth position where the fifth speed driven gear 26 is engaged with the clutch, and a neutral position where the fifth speed driven gear 26 is not engaged. Is switched to.

  The second clutch shaft 9 is provided with a second-speed drive gear 32 and a fourth-speed drive gear 34, which are respectively connected to the second-speed driven gear 33 and the fourth-speed driven gear 35 provided on the speed-change driven shaft 10. It is directly engaged.

  Thus, the second speed gear train G2a including the second speed drive gear 32 and the second speed driven gear 33 and the fourth speed gear train G2b including the fourth speed drive gear 34 and the fourth speed driven gear 35 are combined. , An even-speed gear train group G2 for transmitting power from the second clutch shaft 9 to the shift driven shaft 10.

  As long as the second clutch 31 is engaged, the second clutch shaft is connected via a gear train selected from the second speed gear train G2a and the fourth speed gear train G2b in the even-speed gear train group G2. 9 to the transmission driven shaft 10. A shifter 36 is provided as a member for selecting a gear train as a power transmission target from the even-numbered gear train group G2.

  Here, in the second speed gear train G2a and the fourth gear train G2b, the second speed drive gear 32 and the fourth speed drive gear 34 are provided so as not to rotate relative to the second clutch shaft 9 (both are the second speed drive gear 32 and the fourth speed drive gear 34). The second-speed driven gear 33 and the fourth-speed driven gear 35 are loosely fitted to the speed-change driven shaft 10 (they are rotatable relative to the speed-change driven shaft 10).

  In correspondence with these second and fourth speed gear trains G2a and G2b, the shifter 36 cannot rotate relative to the shift driven shaft 10 between the second speed driven gear 33 and the fourth speed driven gear 35. And it is provided so as to be slidable in the axial direction (front-back direction). The second speed driven gear 33 and the fourth speed driven gear 35 are formed with clutch teeth, respectively, and on each end face of the shifter 36 are formed clutch teeth that can be engaged with the gears 33 and 35, respectively. In other words, the shift clutch 36 and the second speed driven gear 33 form a meshing clutch, and the shifter 36 and the fourth speed gear train 35 form a meshing clutch on the opposite side in the axial direction.

  The shifter 36 is slid along the shift driven shaft 10 to be in a second speed position where only the second speed driven gear 33 is engaged with the clutch, and a fourth speed position where only the fourth speed driven gear 35 is engaged with the clutch. Are switched to three neutral positions where neither the second speed driven gear 33 nor the fourth speed driven gear 35 is engaged.

  A forward drive gear 41 fixed (or formed) on the shift driven shaft 10 and a forward driven gear 42 fixed (or formed) on the counter shaft 11 mesh with each other to form a forward gear composed of the gears 41. The column G3 is formed.

  On the other hand, the reverse drive gear 43 fixed (or formed) on the second clutch shaft 9 meshes with the reverse driven gear 44 loosely fitted to the counter shaft 11 (relatively rotatable with respect to the counter shaft 11). And a reverse gear train G4 composed of the gears 43 and 44.

  Preferably, the forward driven gear 42 in the forward gear train G3 is larger in diameter than the forward drive gear 41, the forward gear train G3 is a reduction gear train, and the backward driven gear 44 in the reverse gear train G4 is a reverse drive gear. 43, the reverse gear train G4 is used as a reduction gear train. The gear ratio of each of the reverse gear train and the forward gear train may be set as appropriate. It may be constituted as.

  A shifter 45 is fitted on the counter shaft 11 so as to be relatively non-rotatable and slidable in the axial direction (front and rear). The shifter 45 and the backward driven gear 44 are formed with clutch teeth that can mesh with each other, and the shifter 45 and the backward driven gear 44 constitute a meshing clutch. The shifter 45 is slid along the counter shaft 10 to be switched between two positions, a reverse position in which the reverse driven gear 44 is engaged with the clutch and a neutral position (or a forward position) separated from the reverse driven gear 44.

  A small-diameter gear 46 is fixed (or formed) on the counter shaft 11, and a large-diameter gear 47 is fixed (or formed) on the output shaft 11, and the small-diameter gear 46 and the large-diameter gear 47 mesh with each other. -It constitutes the final reduction gear train G5 consisting of 47. Depending on the design, the gear train interposed between the counter shaft 11 and the output shaft 12 may be a constant speed gear train or a speed increasing gear train.

  Here, since the first clutch gear 20 and the second clutch gear 30 are respectively meshed with the input gear 7a of the input shaft 7, the first clutch 21 is engaged to receive the rotational power of the input shaft 7 and drive. The rotation direction of the first clutch shaft 8 is the same as the rotation direction of the second clutch shaft 9 driven by receiving the rotational power of the input shaft 7 by engaging the second clutch 31. Therefore, regardless of whether the speed gear train receiving the power belongs to the odd-numbered gear train group G1 or the even-numbered gear train group G2, the rotation direction of the shift driven shaft 10 is constant, and The direction is opposite to that of the first clutch shaft 8 and the second clutch shaft 9. On the other hand, the rotation direction of the counter shaft 11 when receiving and driving the power from the second clutch shaft 9 via the gears 43 and 44 of the reverse gear train G4 is opposite to the rotation direction of the second clutch shaft 9.

  When the vehicle is stopped, a shift operation tool (not shown) provided near the seat 108 of the transport vehicle 100 (for example, the front column 106) is in the neutral position, and both the clutches 21 and 31 are disconnected. At the first speed position, the shifter 45 is at the reverse position.

  When the operating tool is placed at the forward first speed position, the controller controls the electromagnetic proportional valve 71 to gradually increase the engagement pressure in the first clutch 21 from zero to a predetermined pressure, and shifts the first clutch 21 to the half-clutch state. Through to complete engagement. When the operation tool is placed in the reverse position, the controller controls the electromagnetic proportional valve 72 to gradually increase the engagement pressure in the second clutch 31 from zero to a predetermined pressure, and causes the second clutch 31 to pass through a half-clutch state. Allow full engagement.

  When the operating tool is operated at the forward second speed position, the shifter 45 is disposed at the neutral position and the shifter 36 is disposed at the forward second speed position at the time of being placed at the forward first speed position. At about the same time as the reduction in the engagement pressure of the first clutch 21 is started, the application of the engagement pressure to the second clutch 31 which has been in the separated state is started, and the transition from the engagement state of the first clutch 21 to the half-clutch state is performed. In parallel with this, the second clutch 31 is shifted from the disengaged state to the half-clutch state.

  In this way, by increasing the power transmitted from the second clutch shaft 9 to the shift driven shaft 10 via the second speed gear train G2a, the shifter 28 is held at the first speed position, and the shifter 36 is held at the second speed position. It is possible to smoothly shift the forward speed from the first speed to the second speed while keeping the speed. Eventually, the engagement of the second clutch 21 is completed, the separation of the first clutch 31 is completed, and the drive of the shift driven shaft 10 is completely performed by the power from the second clutch shaft 9 via the second speed gear train G2a. It is due to.

  Next, when shifting up from the second speed to the third speed, the shifter 28 is shifted to the third speed position so that the shifters 29 and 45 are in the neutral position and the shifter 36 is in the second speed position. The second clutch 31 may be separated and the first clutch 21 may be engaged.

  In the transmission case 2, a hydraulic pump set 50 containing a pair of fixed displacement type gear pumps 50a and 50b is housed, and a pump as a drive shaft of the gear pumps 50a and 50b of the hydraulic pump set 50 is accommodated. The drive shaft 14 is supported in the front-rear horizontal direction in the vicinity of the input shaft 7 in parallel with the input shaft 7.

  A flat gear 7b fixed (or formed) on the input shaft 7 and a flat gear 14a fixed (or formed) on the pump drive shaft 14 mesh with each other. Power is transmitted. That is, the rotational power of the input shaft 7 is distributed to the first clutch shaft 8 and the second clutch shaft 9 as traveling drive power for driving the output shaft 12, and in parallel therewith, the hydraulic pump set 50 The power is distributed to the pump drive shaft 14 as the power for driving the gear pumps 50a and 50b.

  Next, the configuration of the transmission case 2 and the layout of components constituting the above-described clutch mechanism and gear mechanism inside and outside the transmission case 2 will be described with reference to FIGS.

  In describing these layouts, regarding the position and direction of the dual clutch transmission 1, the dual clutch transmission 1 is disposed in front of the engine 103 in the transport vehicle 100 as described above, and the input shaft 7 and the output shaft 12 are assumed to extend in the front-rear horizontal direction. That is, since the left and right positions are described on the assumption that they are directed to the forward direction of the transport vehicle 100, it should be noted that the left and right positions are opposite to the left and right positions as viewed from the front as shown in FIGS.

  As described above, the transmission case 2 is configured by joining the flywheel housing 3 to the rear of the main housing 4 and joining the lid 5 to the front of the main housing 4. A flange edge 4 a having a bolt boss is formed over the entire periphery of the rear end of the opening of the main housing 4, and the flange edge 4 a is brought into contact with the flange edge 3 a formed over the entire periphery of the front end of the opening of the flywheel housing 3. The flywheel housing 3 and the main housing 4 are separably joined by fastening the flange edges 3a and 4a to each other.

  On the other hand, as shown in FIG. 4, an opening is provided in a part of the front end of the main housing 4, and a front edge 4b is formed so as to surround the opening. A flange edge 5a having a bolt boss formed over the entire periphery of the opening rear end of the lid 5 is brought into contact with the front edge 4b, and the bolt 6 is screwed into each bolt boss formed on the flange edge 5a, so that the main body is screwed. The housing 4 and the lid 5 are detachably fastened.

  A substantially vertical bearing wall 3b is formed in the flywheel housing 3, and the rear wall of the input shaft 7, the first clutch shaft 8, the second clutch shaft 9, and the shift driven shaft are formed by the bearing wall 3b. The rear ends of the 10, the counter shaft 11, and the pump drive shaft 14 are supported by bearings. The flywheel chamber 2a is formed in the flywheel housing 3 behind the bearing wall 3b as described above.

  At the rear end of the flywheel housing 3, the flywheel chamber 2a is opened rearward. By connecting the rear end of the flywheel housing 3 to the engine E, the engine output shaft Ea is inserted into the flywheel chamber 2a. The front end flywheel Eb is arranged. Correspondingly, the rear end of the input shaft 7 extends rearward from the bearing wall 3b, and is substantially coaxial with the engine output shaft Ea via the flywheel Eb in the flywheel chamber 2a. Connected at

  A vertical bearing wall 4c is formed just behind the front end edge 4b of the main housing 4, and the input shaft 7, the first clutch shaft 8, and the second clutch shaft 9 are formed by the bearing wall 4c. Each front portion and each front end of the transmission driven shaft 10 and the counter shaft 11 are supported by respective bearings.

  A cavity as a gear chamber 2b is formed in the main housing 4 behind the bearing wall 4c, that is, on the side closer to the engine E, and the bearing wall 3b of the flywheel housing 3 is connected to the rear end of the gear chamber 2b. Is drawn. In the gear chamber 2b, the odd-numbered gear train group G1, the even-numbered gear train group G2, the forward gear train G3, the reverse gear train G4, the final reduction gear train G5, and the shifters used for controlling the power transmission of these gear trains. 28, 29, 36, 45, etc. are accommodated.

  The odd-numbered gear train group G1, the even-numbered gear train group G2, and the like are arranged in a portion of the gear chamber 2b sandwiched between the front and rear bearing walls 3b and 4c. The flange edge 3a at the front end of the flywheel housing 3 and the main housing 4 joined thereto are further extended to one side on the left and right sides (the right side in this embodiment) than the portions forming the bearing walls 3a and 4c. An extended portion 2b1 (see FIG. 8) is formed in the gear chamber 2b so as to extend further to one side on the left and right sides (right side in this embodiment) than the portion sandwiched by the bearing walls 3b and 4c.

  The output shaft 12 is disposed in the extension 2b1 of the gear chamber 2b. At the wall of the main housing 4 that defines the front end of the extension 2b1, the front of the output shaft 12 is supported via a bearing, and the output shaft 12 is connected to the transmission shaft 121. The front end protrudes forward. On the other hand, a rear portion of the output shaft 12 is rotatably supported via a bearing at a wall portion of the flywheel housing 3 defining a rear end of the expansion portion 2b1. The rear end of the shaft 12 projects rearward.

  Further, as can be seen from FIGS. 8 and 9, a parking brake shaft 13 is disposed on the left and right outer sides (right side in the present embodiment) of the output shaft 12 within the expansion portion 2b1, and a front end thereof is provided. Are supported by the wall of the main housing 4, while the rear end protrudes rearward from the flywheel housing 3, and an arm 13 a is fixed to the rear end.

  A lower end portion of the parking claw member 48 is fixed to the parking brake shaft 13 in the extended portion 2b1 of the gear chamber 2b. The parking claw member 48 extends upward from the lower end portion in an arm shape. A latch claw 48a for meshing with the gear teeth of the large-diameter gear 47 is formed on the upper part. An elongated hole is formed in the upper and lower middle portion of the parking claw member 48 between the lower end portion fixed to the parking brake shaft 13 and the latch claw 48a formed on the upper portion. , An eccentric cam 48b is fitted therein.

  The arm 13a is linked to a parking brake operating tool (not shown) such as a lever and a pedal provided near the seat 108 of the transport vehicle by a link mechanism (not shown). By rotating the eccentric cam 48b by the operation of the operating tool, the parking brake shaft 13 is rotated, and the latch claw 48a formed in the parking claw member 48 in a sawtooth shape is fixed to the output shaft 12. The parking position in which the gear teeth of the diameter gear 47 are engaged is switched to the parking position in which the latch claw 48a is separated from the large diameter gear 47.

  As can be seen from FIG. 9, a vertical bearing wall 4c is formed in the main housing 4 at a position immediately behind the front edge 4b, and the front end of the transmission driven shaft 10 is formed on the bearing wall 4c. It is supported via a bearing.

  The bearing wall 4c serves as a partition for partitioning the rear gear chamber 2b and the front clutch chamber 2c. The input shaft 7, the first clutch shaft 8, and the second clutch shaft 9 are provided on the bearing wall 4c. However, the front end of the input shaft 7 and the front portions of the first clutch shaft 8 and the second clutch shaft 9 are disposed in the clutch chamber 2c. The bearing wall 4c defines the rear end of the clutch chamber 2c. On the other hand, the flange edge 5a is fastened to the front end edge 4b of the main housing 4 via the bolt 6 as described above, so that the front wall of the main housing 4 is formed. The inner surface (rear surface) of the attached lid 5 defines the front end of the clutch chamber 2c.

  The front end of the input shaft 7 is disposed immediately before the bearing wall 4c at the rear end of the clutch chamber 2c, and an input gear 7a is fixed here, and the first clutch gear on the first clutch shaft 8 meshed with the input gear 7a. 20 and the second clutch gear 30 on the second clutch shaft 9 are also provided immediately before the bearing wall 4c.

  Here, in FIG. 8, the respective axes of the input shaft 7, the first clutch shaft 8, the second clutch shaft 9, the shift driven shaft 10, the counter shaft 11, the output shaft 12, and the pump drive shaft 14 in front view are Reference numerals 7X, 8X, 9X, 10X, 11X, 12X, and 14X are shown.

  FIG. 8 shows a shaft 14X of a pump drive shaft, a shaft 7X of an input shaft, a shaft 8X of a first clutch shaft, a shaft 10X of a shift driven shaft, a shaft 9X of a second clutch shaft, and a shaft of a counter shaft. An imaginary line XL is shown in which the core 11X and the output axis 12X are connected in order. It can be seen that this virtual line XL is a zigzag broken line.

  In this way, by arranging these axes so that the axes are arranged in a zigzag shape in a front view, the arrangement space of these axes is prevented from expanding in the left-right direction and the up-down direction. The centralized arrangement of the shafts, which is compact as a whole, makes it possible to reduce the size of the entire transmission case 2 in the horizontal and vertical directions.

  Here, since the position of the axis 7X of the input shaft 7 needs to be arranged on the same axis with respect to the output shaft Ea of the engine E, there is a restriction on the vertical position, and the position is relatively low in the transmission case 2. Distributed to.

  On the other hand, as the first clutch 21 on the first clutch shaft 8 and the second clutch 31 on the second clutch shaft 9, a hydraulic clutch unit 60 (see FIG. 10) described later is used. As described above, since the fine control of the engagement pressure is required as described above, the electromagnetic proportional valves 71 and 72 are used. These electromagnetic proportional valves 71 and 72 are preferably arranged near the clutches 21 and 31 to be controlled, but are arranged at a position lower than the input shaft 7 at a relatively low position as described above. However, when considering that the vehicle runs through the wetland, there is a problem in terms of waterproofness of the solenoid coil.

  Therefore, as shown in FIGS. 6 and 8, first, one of the first and second clutch shafts 8 and 9 is set at a height approximately the same as And the other shaft is arranged above the input shaft 7. In the present embodiment, the output shaft 12 is disposed on the right side of the input shaft 7 (the left side in FIGS. 6 and 8 when viewed from the front), and the second clutch is connected to the counter shaft 11 disposed near the output shaft 12. Since the shaft 9 is linked by the reverse gear train G4 (gears 43 and 44) without passing through the shift driven shaft 10, the second clutch shaft 9 is connected to the right side of the input shaft 7 (in the left-right direction, with the input shaft 7). The first clutch shaft 8 is disposed above the input shaft 7.

  With such an arrangement, the first clutch shafts 8 and 9 are arranged at a suitable height for the electromagnetic proportional valves 71 and 72. Further, as shown in FIG. 8, when viewed from the front, the shaft center 8X of the first clutch shaft 8 and the shaft center 9X of the second clutch shaft 9 are arranged obliquely in the vertical and horizontal directions. As can be seen from the fact that the first clutch gear 20 and the second clutch gear 30 are obliquely arranged in the vertical and horizontal directions, the first clutch 21 and the second clutch 31 Since the first clutch 21 is disposed obliquely in the vertical and horizontal directions (that is, the first clutch 21 is disposed above and to the left of the second clutch 31), as can be seen from the front view layout, In a side view, the lower part of the first clutch 21 and the upper part of the second clutch 31 overlap, while in a plan view (not shown), the right part of the first clutch 21 and the left part of the second clutch 31 overlap, and・ For the second clutch 21 ・ 31 It has shrunk in the vertical and horizontal directions of space required location.

  Further, due to such oblique arrangement of the first and second clutch shafts 8, 9, in the gear chamber 2b, the right side of the first clutch shaft 8 and the upper side of the second clutch shaft 9, as shown in FIG. Space is secured, and by disposing the shift driven shaft 10 here, the entire odd-numbered gear train group G1 and the even-numbered gear train group G2 can be compactly arranged at a relatively high position in the gear chamber 2b. Can be.

  Then, the counter shaft 11 is disposed to the right of the shift driven shaft 10, the output shaft 12 is disposed below the counter shaft 11, and the forward gear train G3 (gears 41 and 42) and the final reduction gear train G5 (46 and 47) are connected. , Are arranged at substantially the same height on the right side of the odd-numbered gear train group G1 and the even-numbered gear train group G2.

  As described above, the odd-numbered gear train group G1, the even-numbered gear train group G2, the forward gear train G3, the reverse gear train G4, and the final reduction gear train G5 are located inside the gear chamber 2b so as not to be lower than the input shaft 7. 8 except that the lower part of the large-diameter gear 47 is immersed in the oil sump in the lower part of the gear chamber 2b, as shown in FIG. The gear mechanism of the dual clutch type transmission 1 is arranged higher than the surface FL, has low agitation resistance of the oil pool, and has high transmission efficiency.

  Even if almost all the gears are arranged higher than the oil surface FL in this way, by arranging the shafts constituting these gears in a zigzag manner as described above, the entirety of these gears can be moved up and down. And, it is accommodated in the gear chamber 2b in a compact state on the left and right.

  On the other hand, the clutch chamber 2c is provided in the gear chamber 2b at the front of the first and second clutch shafts 8 and 9 constituting the odd-numbered gear train group G1 and the even-numbered gear train group G2. The clutch gears 20 and 30 and the first and second clutches 21 and 31 and the space for accommodating the input gear 7a at the front end of the input shaft 7 need only be provided, and the lower end of the clutch chamber 2c is shown in FIG. As can be seen from the arrangement of the front edge 4b of the main housing 4, the main housing 4 is disposed immediately below the input gear 7a and the second clutch gear 31. On the other hand, in front view, the main housing 4 is located below the lower end of the front edge 4b. 4, a lower front end wall 4p extends, and this lower front end wall 4p defines a front end wall of an oil reservoir below the gear chamber 2b.

  Therefore, even if the oil in the oil chamber in the gear chamber 2b communicates with the inside of the clutch chamber 2c via a bearing or the like in the bearing wall 4c and an oil pool is also formed in the clutch chamber 2c, the oil level FL Is not much different from the height of the oil level FL of the oil sump in the gear chamber 2b, and is also below the input gear 7a and the second clutch gear 30 (and the second clutch 31) as shown in FIG. There is no problem with the stirring resistance of the gears and the clutch accommodated in the clutch chamber 2c.

  Then, as shown in FIGS. 5 and 7, the electromagnetic proportional valves 71 and 72 for supplying the hydraulic oil to the first and second clutches 21 and 31 are configured at a high position of the main housing 4 as described above. It is attached to the lid 5 attached to the front edge 4b. Therefore, the electromagnetic proportional valves 71 and 72 are arranged at a high position, which is a preferable arrangement for ensuring waterproofness of each solenoid coil.

  The electromagnetic proportional valves 71 and 72 are provided with a pair of upper and lower bosses formed in a vertical arrangement at one left and right end of the front end of the lid 5 (the left end in the present embodiment). In the example, they are mounted so as to protrude leftward. In the present embodiment, as described above, the first clutch 21 disposed above the input gear 7a is located at a position higher than the second clutch 31 at substantially the same height as the input gear 7a. The electromagnetic proportional valve 72 for the second clutch 31 is disposed below, and the electromagnetic proportional valve 71 for the first clutch 21 is disposed above.

  As described above, since the solenoid proportional valves 71 and 72 protrude the solenoid coil in the left-right direction and are attached to the lid 5 in a state that they can be easily attached and detached, the electromagnetic proportional valves 71 and 72 are in a state where the lid 5 is attached to the main housing 4. By simply rotating the seat 108 and the seat mounting plate 103a as described above, the electromagnetic proportional valves 71 and 72 mounted on the lid 5 can be easily accessed, and the attachment / detachment to the lid 5 for maintenance can be performed. Can also be done easily.

  Further, as shown in FIGS. 5 and 9 and the like, the first and second clutches 21 are attached to the lid 5 at a position further above the electromagnetic proportional valve 71 of the electromagnetic proportional valves 71 and 72. -A relief valve 70 for regulating the operating oil pressure to 31 to a predetermined pressure is mounted.

  As can be seen from FIGS. 5 and 8, a drum shaft 16 and fork shafts 161 and 162 disposed adjacent to and parallel to the drum shaft 16 extend horizontally in the front-rear direction inside the gear chamber 2b. Has been established. Three forks (not shown) are supported on the fork shaft 161 slidably in the axial direction, and are fitted to the shifters 28, 36, and 45, respectively. One fork (not shown) is supported on the fork shaft 162 so as to be slidable in the axial direction, and is fitted to the shifter 29.

  On the other hand, a drum (not shown) having four shift grooves is fixed to the drum shaft 16, and operation pins of the four forks are fitted into each shift groove. With the rotation of, the operation pin fitted into each shift groove moves in the axial direction according to the shape of each shift groove, so that each fork moves in the axial direction of each of the fork shafts 161 and 162. It has become.

  Further, a potentiometer 17b for detecting the rotational position of the drum shaft 16 is provided, and a harness 17c extending from the potentiometer 17b is connected to a controller (not shown) provided on the transport vehicle 100.

  Since these electrical components 17a, 17b, and 17c are arranged on the upper portion of the main housing 4, they are excellent in waterproofness, and are arranged so that connection to the controller and maintenance are easy.

  The actuator 17 and its related electrical components 17a, 17b, and 17c are collectively mounted on the front end face of the main housing 4, so that the access and the seat mounting plate 103a can be accessed and rotated as described above. These are collectively arranged in a place where they can be easily attached and detached.

  Note that, due to the oblique arrangement of the first clutch 21 and the second clutch 31 in the up-down and left-right directions as described above, the upper right portion of the lid 5 is formed in an inclined shape. The actuator 17 and its related electrical components are compactly arranged and attached along the lid 5.

  Further, a starter motor Ec for starting the engine E is attached to a front end surface at an upper left portion of the main housing 4. This portion is located immediately to the right of the right end of the lid 5 attached to the front end of the main housing 4, and is located below the gear chamber 2b, which is configured to secure an oil reservoir below the lower end of the clutch chamber 2c as described later. The starter motor Ec is provided by using a dead space above the left and right expansion portions caused by providing the left expansion portion at the starter motor Ec. Since it is arranged so as to protrude forward on the sides, it is easy to perform maintenance work, and the arrangement is compact.

  In the dual clutch transmission 1, the hydraulic pump unit 50 is housed in the transmission case 2, and oil discharged from the hydraulic pump unit 50 is supplied to the hydraulic clutch unit 60 via the electromagnetic proportional valves 71 and 72. Hydraulic oil is supplied to the first and second clutches 21 and 31 and a part of the discharged oil is used as lubricating oil for the clutches and gears in the gear chamber 2b and the clutch chamber 2c and various bearings. Supplying.

  As a result, even if the gears and clutches in the gear chamber 2b and the clutch chamber 2c are arranged above the oil level FL of the oil reservoir as described above, sufficient lubrication of these gears and clutches is ensured. , Ensuring durability.

  First, the flow of the hydraulic oil / lubricating oil supply system using the discharge oil of the hydraulic pump unit 50 will be described with reference to FIG.

  The hydraulic pump unit 50 includes a first hydraulic pump 50a and a second hydraulic pump 50b that are driven in tandem on the output shaft Ea of the engine E. Here, the first hydraulic pump 50a supplies pressure oil as hydraulic oil for the first and second clutches 21 and 31 regardless of the rotational speed of the engine E, and the second hydraulic pump 50b Only when the rotation speed of the engine E is increased, the discharge oil is added to the discharge oil from the first hydraulic pump 50a and supplied as hydraulic oil for the first and second clutches 21 and 31. .

  That is, the first and second hydraulic pumps 50 a and 50 b of the hydraulic pump unit 50 are both driven by the engine E and suck oil from the oil pool in the gear chamber 2 b of the transmission case 2 via the filter 49. .

  The first hydraulic pump 50a constantly discharges oil as long as the engine E is driven, and the oil is supplied to the electromagnetic passage for the first clutch 21 in an oil passage (operating oil supply oil passage 5b described later) in the lid 5. The hydraulic oil chamber of the first clutch 21 or the hydraulic oil chamber of the second clutch 31 is distributed to a proportional valve 71 and an electromagnetic proportional valve 72 for a second clutch, and is operated in accordance with solenoid control of each of the electromagnetic proportional valves 71. The first clutch 21 or the second clutch 31 is engaged by supplying oil to the hydraulic oil chamber, and the first clutch 21 is released by discharging oil from the hydraulic oil chamber. 21 or the second clutch 31 is separated.

  The second hydraulic pump 50b constantly discharges oil as long as the engine E is driven, and the discharged oil is transmitted from the first hydraulic pump 50a via the check valve 56 only when the unload valve 55 is closed. The fluid is merged with the discharge oil and flows toward the electromagnetic proportional valves 71 and 72. That is, while the unload valve 55 is closed, a large amount of discharge oil from the first and second hydraulic pumps 50a and 50b is supplied as hydraulic oil for the first and second clutches 21 and 31. On the other hand, by opening the unload valve 55, the discharge oil of the second hydraulic pump 50b is returned to the primary side (upstream side) of the first and second hydraulic pumps 50a and 50b.

  The above-described relief valve 70 determines whether the discharge oil from the hydraulic pump unit 50 is only from the first hydraulic pump 50a or a combination of the discharge oils from the first hydraulic pump 50a and the second hydraulic pump 50b. Regardless, the operating oil pressure supplied to the first and second clutches 21 and 31 is kept constant.

  The unload valve 55 is an electromagnetic switching valve, and is an on-off valve that can be automatically switched between an open state and a closed state by a controller based on detection of the rotation speed of the engine E. The controller (not shown) closes the unload valve 55 until the detected engine speed is in the range from the idle speed to the predetermined speed, and outputs the signal from both the first and second hydraulic pumps 50a and 50b. In a region where the discharge oils are merged and the engine speed exceeds the predetermined speed and reaches the highest speed, the unload valve 55 is opened, and substantially only the discharge oil amount from the first hydraulic pump 50a is used. Hydraulic oil is supplied to the first and second clutches 21 and 31.

  As described above, the hydraulic pump unit 50 includes the two fixed displacement hydraulic pumps 50a and 50b, and merges the discharge oils from both to supply the oil to the first and second clutches 21 and 31, or The pump capacity is switched depending on whether the discharge oil is supplied only from the first hydraulic pump 51a.

  As another form in which the pump capacity can be switched in this way, one variable displacement hydraulic pump is provided, such as an axial piston hydraulic pump having a movable swash plate, and the tilt angle of the movable swash plate is changed. For example, a structure in which the volume is changed is also conceivable. In this case, the volume adjusting unit such as the movable swash plate may be controlled by an electric actuator, and the electric actuator may be controlled by a command signal transmitted from a controller based on the detection of the engine speed.

  Dual-clutch type shift that realizes a hydraulic oil supply system to the first and second clutches 21 and 31 and a lubricating oil supply system to each part in the gear chamber 2b and the clutch chamber 2c by the oil discharged from the hydraulic pump unit 50 as described above. The specific structure of the device 1 will be described with reference to FIGS.

  As described above, the oil reservoir is provided in the lower part of the gear chamber 2b having the lower front end wall 4p of the main housing 4 as a front end, and is shown in FIGS. 8 and 12 at a lower position below the oil level FL. As described above, the cylindrical filter 49 is disposed so as to be immersed in the oil reservoir.

  To facilitate the removal of the filter 49 for maintenance, as shown in FIGS. 5, 6, and 8, one side of the left and right sides of the main housing 4 (in this embodiment, the right side provided with the output shaft 12 and the like). A hole for removing the filter is provided on the left side (opposite to the left side), and the hole is closed by a removable cap 49a.

  In the gear chamber 2b, an oil passage pipe member 51 that bends in an L-shape when viewed from the front extends from the inner end of the filter 49, and the upper end thereof is connected to the bottom of the hydraulic pump unit 50.

  The hydraulic pump unit 50 has a housing in which a cover plate 52, a pump block 53, and an oil passage block 54 are joined, and the pump block 53 includes a gear pump as dual first and second hydraulic pumps 50a and 50b, A check valve 56 is provided, and an unload switching valve 55 is provided in the oil passage block 54.

  The front surface of the cover plate 52 abuts the rear surface of the pump block 53, the front surface of the pump block 53 abuts the rear surface of the oil passage block 54, and the cover plate 52, the pump block 53, and the oil passage block 54 are bolted together. The housing is formed by fastening together.

  Further, the front surface of the oil passage block 54 is in contact with the wall of the main housing 4, and the front ends of the bolts 57 penetrating the cover plate 52, the pump block 53 and the oil passage block 54 are connected to the wall of the main housing 4. , The hydraulic pump unit 50 is fixed to the main housing 4.

  As shown in FIG. 12, the mounting position of the hydraulic pump unit 50 in the main housing 4 extends from the portion corresponding to the bottom of the clutch chamber 2c to the upper portion of the lower front end wall 4p below it, as can be seen in FIG. The position in the left-right direction is a portion near the left end of the main housing 4. The unload valve 55 is mounted from the outside of the main housing 4 (the transmission case 2) into the oil passage block 54 via a front-rear through hole 4h formed in the upper part of the lower front end wall 4p of the main housing 4. Have been.

  Each of the first hydraulic pumps 50a is a gear pump formed by combining an inner rotor and an outer roller surrounding the inner rotor. The pump drive shaft 14 penetrates through the cover plate 52, and its front end is disposed in the pump block 53. The first and second hydraulic pumps 50a and 50b are connected to the front end of the pump drive shaft 14. I have.

  An oil passage 51 a is formed in the oil passage pipe member 51 so as to penetrate from a lower end connected to the filter 49 to a lower end connected to the hydraulic pump unit 50. The upper end of the oil passage pipe member 51 is connected to the bottom end of the joint between the cover plate 52 and the pump block 53.

  A suction oil passage 52a is formed along the front surface of the cover plate 51 and extends vertically upward from the lower end to the middle part in the vertical direction. The lower end of the suction oil passage 52a is at the upper end of the oil passage 51a in the oil passage pipe member 51. The upper end of the suction oil passage 52a communicates with the suction port of the first hydraulic pump 50a along the rear surface of the pump block 53.

  Further, a discharge oil passage 52b is formed in the front surface of the cover plate 52 to extend vertically upward from a position slightly above the suction oil passage 52a, and a lower end of the discharge oil passage 52b is connected to a discharge end of the first hydraulic pump 50a. It is in communication with the port.

  In a portion of the pump block 53 above the first and second hydraulic pumps 50a and 50b, a hydraulic oil supply oil passage 53b in the front-rear horizontal direction is formed in a front-rear penetrating shape. It is connected to the upper end of a discharge oil passage 52b formed along the front surface.

  Corresponding to the hydraulic oil supply oil passage 53b in the pump block 53, a front and rear horizontal hydraulic oil supply oil passage 54d is formed in the upper part of the oil passage block 54 so as to penetrate in the front-rear direction. Is connected to the front end of a hydraulic oil supply oil passage 53b in the pump block 53.

  Further, as described above, the front and rear horizontal hydraulic oil supply oil passage 4d is formed in the wall of the main housing 4 corresponding to the bottom of the clutch chamber 2c, and the rear end of the hydraulic oil supply oil passage 4d is It is connected to a front end of a hydraulic oil supply oil passage 54 d in the road block 54.

  In the pump block 53, a second suction oil passage 53a is formed so as to communicate the suction port of the first hydraulic pump 50a with the suction port of the second hydraulic pump 50b in front thereof.

  A part of the oil flowing from the oil passage 51a of the oil passage pipe member 51 to the suction port of the first hydraulic pump 50a through the suction oil passage 52a of the cover plate 52 is partially driven by the first hydraulic pump 50a. The pressure is fed to the discharge port of the first hydraulic pump 50a, and the other flows into the suction port of the second hydraulic pump 50b via the second suction oil passage 53a.

  A check valve 56 is provided in the pump block 53 and the oil passage block 54 so as to penetrate the joint surface between the pump block 53 and the oil passage block 54. The front end is connected to a communication oil passage 54c formed in the oil passage block 54, and the front end is connected to the oil supply passage 53c from the communication oil passage 54c to the hydraulic oil supply oil passage 53b. It is configured to allow only flow.

  The communication oil passage 54c communicates with an inlet port of an unload valve 55 mounted in the oil passage block 54. In the oil passage block 54, a return oil passage 54a connecting the suction port of the second hydraulic pump 50b and the outlet port of the unload valve 55, and a discharge port and a communication oil passage 54c of the second hydraulic pump 50b are provided. And a discharge oil passage 54b is formed.

  The second hydraulic pump 50b is driven by the pump drive shaft 14 in synchronism with the first hydraulic pump 50a. The second hydraulic pump 50b receives the oil taken into the suction port via the second suction oil path 53a from the discharge port to the discharge oil path 54b. Through the communication oil passage 54c.

  At this time, if the unload valve 55 is closed, the oil flowing into the communication oil passage 54c from the discharge oil passage 54b opens the check valve 56, and the hydraulic oil supply oil passage 53b in the oil passage block 53 is opened. At the discharge oil passage 53b, merges with the oil discharged from the first hydraulic pump 50a via the discharge oil passage 52b, and flows to the hydraulic oil supply oil passage 54d and the hydraulic oil supply oil passage 4d. .

  On the other hand, if the unload valve 55 is open, the oil flowing into the communication oil passage 54c from the discharge oil passage 54b is supplied from the unload valve 55 to the suction port of the second hydraulic pump 50b via the return oil passage 54a. It is returned to the suction port of the first hydraulic pump 50a via the second suction oil passage 53a.

  A hydraulic oil supply oil passage 5b is formed in the lid 5 from a portion serving as a bottom wall of the clutch chamber 2c to a portion serving as a front wall of the clutch chamber 2c. The lower end of the hydraulic oil supply oil passage 5b is an oil hole in the front-rear horizontal direction, and the rear end is connected to the front end of the hydraulic oil supply oil passage 4d in the main housing 4.

  As shown in FIG. 12, a horizontal oil hole is formed rearward from a relief valve 70 provided at the upper left portion of the lid 5, and a front-rear direction connected to a hydraulic oil supply oil passage 4 d of the main housing 4. As shown in FIG. 7, an oil hole is vertically formed along the left end of the lid 5 from the front end of the oil hole to the rear end of the oil hole in the front-rear direction connected to the relief valve 70. . The vertical oil hole, an oil hole extending horizontally rearward from the lower end of the vertical oil hole to the hydraulic oil supply oil passage 4 d of the main housing 4, and a relief valve 70 extending from the lower end of the vertical oil hole. The hydraulic oil supply oil passage 5b in the lid 5 is constituted by an oil hole connected in the front horizontal direction.

  Further, as shown in FIG. 7 and FIG. 12, in the lid 5, the upper and lower portions of the vertical oil hole of the hydraulic oil supply oil passage 5 b extend from the upper and lower middle portions of the second clutch shaft 9 located on the right side thereof, A left-right horizontal oil hole is formed up to the groove 9a, and this oil hole is used as a second clutch hydraulic oil supply oil passage 5d. The left and right horizontal oil holes are drilled from the upper and lower middle portions of the oil hole to the annular groove 8a of the first clutch shaft 8 located on the right side of the oil hole. 5c.

  Of the upper and lower electromagnetic proportional valves 71 and 72 mounted from the left end of the lid 5, the lower electromagnetic proportional valve 72 is connected to the vertical oil hole of the hydraulic oil supply oil passage 5b. The electromagnetic proportional valve 72 is connected to the vertical oil hole of the hydraulic oil supply oil passage 5b, and the discharge port is connected to the second oil supply passage 5b. It is in communication with the hydraulic oil supply oil passage 5d for the clutch.

  Further, the upper electromagnetic proportional valve 71 is fitted into the lid 5 up to the starting point of the first clutch hydraulic oil supply oil passage 5c connected to the vertical oil hole of the hydraulic oil supply oil passage 5b. The electromagnetic proportional valve 71 has a suction port communicating with a vertical oil hole of the hydraulic oil supply oil passage 5b and a discharge port communicating with the first clutch hydraulic oil supply oil passage 5c.

  As shown in FIG. 9, the cover 5 has a shaft hole 5 f into which the front end of the first clutch shaft 8 is fitted, and the shaft hole into which the front end of the second clutch shaft 9 is fitted. 5h are formed. An annular groove 8a is fitted on the outer peripheral surface of the first clutch shaft 8 which is slidably and rotatably fitted on the inner peripheral surface of the shaft hole 5f, and is relatively slidably and rotatably fitted on the inner peripheral surface of the shaft hole 5h. Annular grooves 9a are formed on the outer peripheral surface of the combined second clutch shaft 9, respectively.

  As can be seen from FIG. 7, the terminal end (right end) of the first clutch operating oil supply oil passage 5c opens on the inner peripheral surface of the shaft hole 5f, and the annular groove of the first clutch shaft 8 in the shaft hole 5f. 8a. On the other hand, the terminal end (right end) of the second clutch hydraulic oil supply oil passage 5d is opened on the inner peripheral surface of the shaft hole 5h and communicates with the annular groove 9a of the second clutch shaft 9 in the shaft hole 5h. .

  As shown in FIG. 9, a working oil passage 8 b in the axial direction is formed in the first clutch shaft 8, and a working oil passage 9 b in the axial direction is formed in the second clutch shaft 9. Has been established. One end (the front end in the present embodiment) of each of the hydraulic oil passages 8b and 9b communicates with each of the annular grooves 8a and 9a via a radial oil hole, and the other end (the other end) of each of the hydraulic oil passages 8b and 9b. The rear end in the embodiment) is opened on the outer peripheral surface of each clutch shaft 8, 9 through another radial oil hole, and the first and second clutches 21, 31 which are the hydraulic clutch unit 60 are respectively opened. It communicates with the hydraulic oil chamber. The configuration of the hydraulic clutch unit 60 as each of the first and second clutches 21 and 31 will be described later in detail.

  As can be seen from FIGS. 7 and 9, a linear oil hole is formed in the lid 5 obliquely to the lower right of the relief valve 70 so as to guide the oil discharged from the relief valve 70 as lubricating oil. The hole is a lubricating oil passage 5e. The lubricating oil passage 5e is connected to the front ends of the shaft holes 5f and 5h into which the front ends of the clutch shafts 8 and 9 are fitted.

  A lubricating oil passage 8c is formed in the first clutch shaft 8 in the axial direction in parallel with the working oil passage 8b, and a front end thereof is opened at a front end of the first clutch shaft 8. A gap is provided between the front end of the shaft hole 5f and the front end of the first clutch shaft 8, and this gap is defined as an oil transfer chamber 5f1. Thus, the discharged oil from the relief valve 70 can flow from the lubricating oil passage 5e into the lubricating oil passage 8c via the oil transfer chamber 5f1.

  On the other hand, a lubricating oil passage 9c is formed in the second clutch shaft 9 in the axial direction in parallel with the working oil passage 9b, and its front end is opened at the front end of the second clutch shaft 9. I have. A gap is provided between the front end of the shaft hole 5h and the front end of the second clutch shaft 9, and this gap is defined as an oil transfer chamber 5h1. Thus, the discharged oil from the relief valve 70 can flow from the lubricating oil passage 5e into the lubricating oil passage 9c via the oil transfer chamber 5h1.

  As shown in FIG. 9, in the clutch chamber 2c, in each of the clutch shafts 8 and 9, oil holes are branched radially from the lubricating oil passages 8c and 9c, and the oil holes are divided into the clutch shafts 8 and 9. 9, an oil for suppressing the centrifugal oil pressure of the first and second clutches 21 and 31 attached to this portion to the centrifugal oil pressure cancellation chamber 60b, which will be described later, and to the clutch plates 62 and 63. As the lubricating oil, the oil discharged from the relief valve 70 is supplied.

  Further, the lubricating oil passages 8c and 9c extend to the respective rear ends of the first clutch shaft 8 and the second clutch shaft 9 that are supported by the bearing wall 3b at the rear end of the gear chamber 2b. That is, each of the clutch shafts 8 and 9 is formed to penetrate in the front-rear direction. Therefore, the oil that has passed through the lubricating oil passages 8c and 9c flows out from the rear ends of the respective clutch shafts 8.9 and lubricates the bearings that support the rear ends of the respective clutch shafts 8.9 and the gear chamber 2b. It is returned to the oil pool inside.

  Further, as shown in FIG. 9, the transmission driven shaft 10 and the counter shaft 11 are also supported by the bearing wall 3b from the front ends of the shafts 10 and 11 supported by the bearing wall 4c. Lubricating oil passages 10a and 11a extending in the axial direction are formed in the front and rear ends of the respective shafts 10 and 11 so as to extend to the rear ends.

  The main housing 4 is provided with an oil hole extending in the front-rear horizontal direction from a vertical surface facing the front end of the speed change driven shaft 10 in the bearing wall 4c to a front end surface of the main housing 4 in contact with the lid 5. This is the lubricating oil passage 4e. On the other hand, an oil hole in the front-rear horizontal direction is formed from a vertical surface facing the front end of the counter shaft 11 in the bearing wall 4c of the main housing 4 to a front end surface of the main housing 4 abutting on the lid 5. This is a lubricating oil passage 4f.

  In the lid 5, as shown in FIGS. 7 and 9, the lubricating oil passage 5e, which is a diagonally straight oil hole when viewed from the front, is connected to the oil receiving chamber 5f1 (the front end of the shaft hole 5f). An oil hole is formed upward (more specifically, diagonally to the upper right) from a portion between the oil receiving chamber 5h1 (the front end of the shaft hole 5h) and a connection portion with the oil receiving chamber 5h1 (in front of the shaft hole 5h). An oil hole is formed, and the rear end is connected to the front end of the lubricating oil passage 4e of the main housing 4. These oil holes in the lid 5 form a lubricating oil passage 5g for branching from a middle part of the lubricating oil passage 5e and guiding oil to the lubricating oil passage 4e of the main housing 4.

  Through the lubricating oil passage 5g of the lid 5 and the lubricating oil passage 4e of the main housing 4, the oil discharged from the relief valve 70 is introduced into the lubricating oil passage 10a in the shift driven shaft 10 and eventually the shift driven. It flows out from the rear end of the shaft 10 and returns to the oil pool in the gear chamber 2b.

  The end of the lubricating oil passage 5e is connected to the shaft hole 5h into which the front end of the second clutch shaft 9 is fitted. An oil hole (in the upper right diagonal direction) is formed, a horizontal oil hole is formed behind the upper end of the oil hole, and the rear end is connected to the front end of the lubricating oil passage 4f of the main housing 4. These oil holes in the lid 5c constitute a lubricating oil passage 5i for branching from the terminal end of the lubricating oil passage 5e and guiding oil to the lubricating oil passage 4f of the main housing 4.

  The oil discharged from the relief valve 70 is introduced into the lubricating oil passage 11a in the counter shaft 11 through the lubricating oil passage 5i of the lid 5 and the lubricating oil passage 4f of the main housing 4. From the rear end, and is returned to the oil pool in the gear chamber 2b.

  In the gear chamber 2b, the outer peripheral surface of the first clutch shaft 8 is provided with the inner peripheral surface of the fifth speed drive gear 26, and the outer peripheral surface of the shift driven shaft 10 is provided with the first speed driven gear 23 and the third speed driven gear 25. , The second-speed driven gear 33 and the fourth-speed driven gear 35, and the inner peripheral surface of the reverse driven gear 44 on the outer peripheral surface of the counter shaft 11. Wearing freely. In order to lubricate the bush, a radial oil hole branches off from the lubricating oil passage 8c in the first clutch shaft 8, the lubricating oil passage 10a in the shift driven shaft 10, and the lubricating oil passage 11a in the counter shaft 11. An opening is formed on the outer peripheral surface of each shaft to face each bush.

  In this way, the oil discharged from the relief valve 70 for regulating the operating oil pressure to the first and second clutches 21 and 31 attached to the lid 5 is supplied to the first and second clutches 21 and 31 in the clutch chamber 2c. The lubricating oil is supplied to each gear loosely fitted to the shaft in the clutch chamber 2b. As described above, almost all gears and clutches in the gear chamber 2b and the clutch chamber 2c are filled with oil. Even if the structure is arranged higher than the surface FL, the lubricating oil is reliably supplied to these members.

  In the above, the supply structure of the clutch operating oil and the lubricating oil has been described on the assumption that the hydraulic pump unit 50 is disposed in the gear chamber 2b as shown in FIG. This hydraulic pump unit may be arranged in the clutch chamber 2c.

  FIG. 13 shows a structure in which a hydraulic pump unit 50A of another embodiment is arranged in the clutch chamber 2c. The embodiment of FIG. 13 will be described.

  In the above-described embodiment, the lower end of the clutch chamber 2c is disposed immediately below the input gear 7a. However, in the present embodiment, the clutch chamber 2c is further lowered from this position to a position corresponding to the lower end of the gear chamber 2b. Has been extended to. That is, the opening defined by the front edge 4b of the main housing 4 is expanded downward, and the front edge 4b is formed over substantially the entire circumference of the front end of the main housing 4, and the flange edge 5a of the lid 5 is correspondingly formed. Are also formed to extend downward.

  In this manner, the lower expansion chamber 2d is formed below the position corresponding to the lower end of the clutch chamber 2c of the above-described embodiment, and the portion of the main housing 4 which was the lower front end wall 4p in the previous embodiment is replaced by the gear chamber 2b. The lower partition wall 4p1 partitions the lower portion from the lower expansion chamber 2d of the clutch chamber 2c, and the lower expansion portion 5p of the lid 5 serves as the front wall of the lower expansion chamber 2d.

  An oil reservoir is provided in the lower expansion chamber 2d, and a filter 49 is attached in the previous embodiment to the wall of the main housing 4 corresponding to the right wall of the lower expansion chamber 2d so as to be immersed in the oil reservoir. A hole similar to the hole previously formed is formed, and the filter 49 is inserted into the hole and the filter 49 is disposed in the lower part of the lower expansion chamber 2d.

  In addition, a through hole 4p2 that connects the rear gear chamber 2b and the front lower expansion chamber 2d is formed below the lower partition wall 4p1, and an oil reservoir in the gear chamber 2b is formed through the through hole 4p2. The oil can flow between the clutch chamber 2c and the oil reservoir in the lower expansion chamber 2c.

  Above the lower expansion chamber 2d, the hydraulic pump unit 50A is disposed so as to be sandwiched between the lower partition 4p1 of the main housing 4 and the lower expansion portion 5p of the lid 5. As the housing of the hydraulic pump unit 50A, only the pump block 53 and the oil passage block 54 are used, and the rear surface of the pump block 53 abuts on the front end surface of the upper part of the lower partition wall 4p1 of the main housing 4, and the oil passage block 54 The front surface is in contact with the inner side surface (rear surface) of the upper part of the lower extended portion 5p of the lid 5.

  The bolt 57 is passed through the oil passage block 54 and the pump block 53 from the front, and its rear end is screwed into the lower partition wall 4p1 of the main housing 4 so that the pump block 53, which is the housing of the oil passage pump unit 50A, and the oil passage The block 54 is fixed to the main housing 4.

  The bolt 57 may be inserted from behind into the pump block 53 and the oil passage block 54 and screwed into the lid 5 to fasten the housing of the hydraulic pump unit 50A to the lid 5, or It may be fastened to both the housing 4 and the lid 5.

  Arrangement of first and second hydraulic pumps 50a and 50b and oil passages 53a and 53b in pump block 53, arrangement of unload valve 55 and oil passages 54a, 54b, 54c and 54d in oil passage block 54, and pump The arrangement of the check valve 56 in the block 53 and the oil passage block 54 is the same as that of the hydraulic pump unit 50.

  However, with respect to the unload valve 53 in the oil passage block 54, the portion disposed immediately before the oil passage block 54 is not the lower front end wall 4 p of the main housing 4 but the upper part of the lower extension portion 5 p of the lid 5. is there. Corresponding to this, a front-rear hole 5k is provided in the upper part of the lower extension 5p of the lid 5, and the unload valve 53 is fitted from the front end of the lower extension 5p of the lid 5 through the hole 5k. It is assumed. Thus, even in a configuration in which the lower expansion chamber 2d is additionally formed in the clutch chamber 2c, the unload valve 55 can be pulled out to the front of the transmission case 2, thereby maintaining the maintainability.

  Since the oil passage block 54 and the lid 5 are in direct contact with each other, the front end of the hydraulic oil supply oil passage 54 d in the oil passage block 54 is connected to the lower end of the hydraulic oil supply oil passage 5 b in the lid 5. It is directly connected to the rear end of the oil hole in the front-rear direction.

  The upper end of the oil passage pipe member 51 extended from the filter 49 is connected to the bottom end of the joint between the pump block 53 and the oil passage block 54. Correspondingly, a suction oil passage 54a1 extending downward from the return oil passage 54a formed along the rear surface of the oil passage block 54 so as to communicate with the suction port of the second hydraulic pump 50b is formed in a groove shape. The lower end of the suction oil passage 54a1 is connected to the upper end of the oil passage 51a in the oil passage pipe member 51.

  On the other hand, instead of the cover plate 52, a vertical discharge oil passage 4i is formed in a groove shape along the front surface of the lower partition wall 4p1 of the main housing 4 which is in contact with the rear surface of the oil passage block 53. The upper end thereof is connected to the discharge port of one hydraulic pump 50a, and the upper end thereof is connected to the rear end of the discharge oil passage 53b in the oil passage block 53. The pump drive shaft 14 is rotatably supported by a lower partition wall 4p1 of the main housing 4 via a bearing, and has a front end protruding into the pump housing 53.

  The control of the discharge amount by the hydraulic clutch operating oil supply hydraulic pump unit 50 or 50A and the effect thereof as described above will be described based on a correlation diagram of the discharge oil amount Q with respect to the rotation speed N of the engine E in FIG.

  The controller (not shown) closes the unload valve 55 when the rotation speed N of the engine E detected by the rotation speed sensor or the like is less than the predetermined value N2, and operates the first and second hydraulic pumps 50a and 50b. The oil discharged from both sides is supplied to a hydraulic oil supply oil passage 5 b in the lid 5. The discharge oil amount Q increases as the engine speed N increases, and is required for the operation of the first clutch 21 or the second clutch 31 at a stage where the engine speed N reaches the idling speed N1. Is set to reach only the amount Q1.

  Therefore, for example, if the shifter 28 is set at the first forward speed position and the shifter 45 is set at the reverse position, and the first clutch 21 is engaged while the engine E is idling, the transport vehicle 100 can be smoothly moved at the first speed. When the second clutch 31 is engaged at the idling rotational speed, the transport vehicle 100 can be started backward smoothly.

  After the hydraulic oil chamber 60a described later in the engaged clutch 21 or 31 is filled with the hydraulic oil of the oil amount Q1, the oil supplied from the hydraulic pump unit 50 (50A) to the hydraulic oil supply oil passage 5b. Is released to the lubricating oil passage 5e via the relief valve 70.

  As the engine speed N increases from the idling speed N1, the discharged oil amount Q increases, and the hydraulic oil amount Q1 required to engage one of the first clutch 21 or the second clutch 31 is reduced. The oil discharged in excess is released from the relief valve 70 to the lubricating oil passage 5e, and is supplied as lubricating oil to each part of the clutch chamber 2c and the gear chamber 2b that requires lubricating oil.

  Eventually, the discharge oil amount Q reaches the upper limit value Q3 (hereinafter simply referred to as “upper limit value Q3”) of the total oil amount required for the dual clutch transmission 2 as a whole. This is the sum of the clutch operating oil amount Q1 and the upper limit value Q2 of the lubricating oil amount required for the entire dual clutch transmission 2 (hereinafter referred to as “lubricating oil upper limit amount Q2”).

  At this time, the detected engine speed N has reached the predetermined value N2. Based on the detection of the engine speed N having the predetermined value N2, the controller opens the unload valve 55 which has been closed until then. I do. As a result, the oil is discharged from the hydraulic pump unit 50 (50A) only by the first hydraulic pump 50a, and the discharge oil amount Q is halved here from the upper limit Q3, but the hydraulic oil amount Q1 is secured. ing.

  The amount Q of oil discharged only from the first hydraulic pump 50a increases as the engine speed N increases, and reaches the upper limit value Q3 when the engine speed N reaches the maximum speed Nmax. And

  Until the engine speed N reaches the maximum speed Nmax, the unload valve 55 is kept closed to discharge the oil discharged from both the first hydraulic pump 50a and the second hydraulic pump 50b to the hydraulic oil supply oil passage 5b. In the range of the engine speed N from the predetermined value N2 to the maximum rotation speed Nmax, the amount of oil exceeding the upper limit Q3 flows to the hydraulic oil supply passage 5b as the engine speed N increases. Continue to be supplied. When the engine speed N reaches the maximum speed Nmax, a discharge oil amount Q that is approximately twice as large as the upper limit value Q3 is supplied.

  In the region of the engine speed N from the predetermined value N2 to the maximum speed Nmax, the relief valve 70 continues to release an amount of oil exceeding the upper limit amount Q2 of the lubricating oil to the lubricating oil passage 5e and is used as the lubricating oil. Without returning to the oil chamber in the gear chamber 2b (and the clutch chamber 2c), the power of the engine E is wasted for driving the hydraulic pumps 50a and 50b.

  Therefore, as described above, when the engine speed N reaches the predetermined value N2, the unload valve 55 is opened, and the second hydraulic pump 50b is unloaded (no-load operation), so that the maximum value from the predetermined value N2 is reached. In the region of the engine rotation speed N up to the rotation speed Nmax, the energy consumption SE for driving the second hydraulic pump 50b represented as a shaded portion in FIG. 14 is omitted, and the fuel efficiency of the transport vehicle 100 can be improved. it can.

  In the present embodiment, the first hydraulic pump 50a and the first hydraulic pump 50b have the same displacement as the first hydraulic pump 50a, but the present invention is not limited to this.

  Next, the configuration of the hydraulic clutch unit 60 provided as the first and second clutches 21 and 31 will be described with reference to FIGS. Note that FIG. 10 discloses a hydraulic clutch unit 60 as the first clutch 21, and a configuration of the hydraulic clutch unit 60 as the second clutch 31 will be described below. Since the configuration is the same as that of the configuration 60, the description is omitted.

  The hydraulic clutch unit 60 includes a clutch case 61 fixedly mounted on the clutch shaft 8, the clutch gear 20 loosely fitted on the clutch shaft 8, and interposed between the clutch case 61 and the clutch gear 20 within the clutch case 61. The clutch plates 62 and 63, the receiving plate 64, the retaining ring 65, the piston 66, the spring 67, the centrifugal hydraulic canceller (hereinafter simply referred to as "canceller") 68, and the lubricating oil guide plate 69 are combined.

  In the clutch case 61, the inner peripheral surface of the center boss 61a is fixed to the outer peripheral surface of the clutch shaft 8, and a vertical plate portion 61b extends in a centrifugal manner from the front end of the central boss portion 61a. Behind the outer peripheral edge of 61b, a peripheral portion 61c is formed to extend so as to surround the center boss portion 61a.

  A bearing is interposed between the inner peripheral surface of the clutch gear 20 disposed behind the clutch case 61 and the outer peripheral surface of the clutch shaft 8, and the clutch gear 20 is loosely fitted to the clutch shaft 8. A cylindrical portion 20a extends forward from the clutch gear 20 and is provided in a space between a central boss portion 61a of the clutch case 61 and a peripheral portion 61c around the cylindrical portion 20a (hereinafter, this space is referred to as a "clutch case 61"). Inside space).

  An inner peripheral edge of a plurality of steel plates 62 arranged front and rear is engaged with the outer peripheral portion of the cylindrical portion 20a of the clutch gear 20 so as to be relatively non-rotatable and slidable in the axial direction (front-rear direction). The outer peripheral edges of a plurality of friction plates 63 arranged in front and rear are engaged with the inner peripheral portion of the peripheral portion 61c of the 61 so as to be relatively non-rotatable and slidable in the axial direction (front-rear direction). The steel plates 62 and the friction plates 63 are alternately arranged back and forth as clutch plates.

  Of these clutch plates 62 and 63, a receiving plate 64 is disposed immediately after the rearmost clutch plate, and is engaged with the circumferential portion 61 c of the clutch case 61 so as to be relatively non-rotatable. Are locked by a retaining ring 65 so as not to move in the axial direction.

  The piston 66 is centered in the front half of the internal space of the clutch case 61 in front of the front end of the tubular portion 20a of the clutch gear 20 and the frontmost end of the clutch plates 62 and 63. It is arranged so as to be slidable along the boss 61a in the axial direction (front-back direction). A portion of the internal space of the clutch case 61, which is located forward of the piston 66, is a working oil chamber 60a.

  A rear end of the working oil passage 8b in the clutch shaft 8 has a radial oil hole in the clutch shaft 8 and a working oil passage 61d formed in front of a center boss 61a of the clutch case 61. Through the hydraulic oil chamber 60a.

  The oil from the discharge port of the electromagnetic proportional valve 71 is supplied to the hydraulic oil chamber 60a via the hydraulic oil supply oil passage 5c, the annular groove 8a, the hydraulic oil passage 8b, and the hydraulic oil passage 61d, so that the oil pressure is used. When the piston 66 slides rearward and presses the clutch plates 62 and 63 between the piston 66 and the receiving plate 64, the clutch gear 20 is engaged with the clutch case 61 so as not to rotate relatively. And is engaged with the clutch shaft 8 via the clutch shaft 8 so as not to rotate relatively. That is, the clutch is engaged.

  Conversely, when the oil escapes from the hydraulic oil chamber 60a, the piston 66 slides forward by the action of the spring 67, so that the clutch plates 62 and 63 are separated from each other, and the clutch is disengaged.

  A central boss 66a slidably fitted to the central boss 61a of the clutch case 61 is formed on the piston 66, and a peripheral opening having a rear opening shape is formed around the front end of the central boss 66a. 60b are formed.

  On the other hand, a space is secured between the outer peripheral surface of the central boss portion 66a of the piston 66 and the inner peripheral surface of the cylindrical portion 20a of the clutch gear 20 surrounding the periphery of the inner space of the clutch case 61. In the space, a cup-shaped canceller 68 having an opening at the front end is arranged, and the inner peripheral edge of a vertical plate portion 69a formed at the rear end of the canceller 68 is positioned rearward of the rear end of the center boss portion 66a of the piston 66. It is attached to the outer peripheral surface of the center boss 61a.

  A lubricating oil guide plate 69 is fixed to the center boss portion 61a behind the vertical plate portion 69a so as to be in contact with the vertical plate portion 69a, and is in contact with the rear end of the canceller 68. ing.

  In the canceller 68, a front end edge 68c surrounding the front end opening is disposed in the recess 66b of the piston 66, and its outer peripheral surface is slidably fitted to the inner peripheral surface of the recess 66b. A spring 67 is interposed between a vertical plate portion of the piston 66 defining the front end of the concave portion 66b and a vertical plate portion 68a at the rear end of the canceller 68.

  A peripheral portion 68b is formed on the canceller 68 so as to extend from an outer peripheral end of the vertical plate portion 68a to a front end portion 68c, and the peripheral portion 68b surrounds a center boss portion 66a of the piston 66. Are arranged as follows.

  The spring 67 is disposed so as to pass through a gap between the inner peripheral surface of the peripheral portion 68b and the outer peripheral surface of the central boss 66a. By the urging force of the spring 67, the piston 66 is urged forward, that is, in the clutch disengagement direction, and the hydraulic pressure applied to the piston 66 is applied in the clutch engagement direction against the urging force of the spring 67. ing. On the other hand, the canceller 68 is always kept in a state where the vertical plate portion 68a at the rear end is in contact with the lubricating oil guide plate 69 by the urging force of the spring 67.

  While the hydraulic oil is being removed from the hydraulic oil chamber 60a, the front end of the piston 66 is originally held in contact with the vertical plate portion 61b of the clutch case 61 by the biasing force of the spring 67, and the clutch plates 62, 63 Are kept separated, that is, the clutch is kept separated. However, at the time of high rotation, centrifugal oil pressure is generated in the oil slightly remaining in the hydraulic oil chamber 60a, and this centrifugal oil pressure is applied to the piston 66 in the direction of pressing the clutch plates 62 and 63 against the spring 67 (backward). Take it. As a result, there is a possibility that a problem may occur in which the clutch is unexpectedly engaged to cause power loss or wear of members such as the clutch. To prevent this, it is conceivable to use a spring 67 having a strong urging force, but this may lead to an increase in cost.

  Therefore, in the hydraulic clutch unit of the dual clutch transmission 1 according to the present application, the canceller 68 is provided, and a cancel chamber 60b facing the hydraulic oil chamber 60a in front of the piston 66 is provided between the canceller 68 and the piston 66. Oil is introduced into the canceller chamber 60b so as to oppose the oil pressure in the hydraulic oil chamber 60a to prevent the clutch plates 62 and 63 from being inadvertently pressed by centrifugal oil pressure.

  The lubricating oil supplied from the lubricating oil passage 8c in the clutch shaft 8 to the hydraulic clutch unit 60 is used as the oil to be introduced into the cancel chamber 60b. That is, in the clutch shaft 8, a radial oil hole 8 c 1 is branched from the axial lubricating oil passage 8 c, and the outer end thereof is opened at the outer peripheral surface of the clutch shaft 8. On the other hand, a radial lubricating oil hole 61e penetrating inside and outside is formed in the front and rear part of the center boss 61a of the clutch case 61, and the opening end of the lubricating oil hole 61e on the inner peripheral surface of the center boss 61a. Is connected to the opening end of the oil hole 8c1 on the outer peripheral surface of the clutch shaft 8.

  The outer end opening of the lubricating oil passage 61e faces the inner peripheral surface of the center boss 66a of the piston 66, and the lubricating oil overflowing from the lubricating oil passage 61e is formed in the center boss 66a so as to penetrate inside and outside. The oil is introduced into the cancel chamber 60b through the lubricating oil hole 66c or the cancel oil hole 66d.

  The lubricating oil hole 66c is provided so as to communicate with the lubricating oil hole 61e of the clutch case 61 when the piston 66 is at the clutch engagement position, and the diameter of the lubricating oil hole 66c is fed to the clutch plates 62 and 63 as lubricating oil. The dimensions are set so that the amount of oil can be taken in.

  The cancel oil hole 66d is provided so as to communicate with the lubricating oil hole 61e when the piston 66 is at the clutch disengaged position, and has a bore whose working oil in the working oil chamber 60a cooperates with the spring 67. Is small so as to take in only the oil corresponding to the centrifugal hydraulic pressure into the cancel chamber 60b.

  That is, these oil holes 66c and 66d supply only the oil corresponding to the centrifugal oil pressure when the clutch is disengaged and the oil supplied to the clutch plates 62 and 63 as lubricating oil when the clutch is engaged, in addition to the cancel chamber 60b. Configuration.

  The clutch plates 62 and 63 are arranged so as to surround the circumferential portion 68b of the canceller 68, that is, radially outside the canceller 68. The existing lubricating oil hole 66c in the piston 66 originally lubricates the oil that overflows from the lubricating oil hole 66c to the clutch plates 62 and 63 disposed radially outward through the internal space of the clutch case 60. It is arranged so that it can be supplied as oil.

  By disposing the canceller 68 in the internal space of the clutch case 60 so as to shield the clutch plates 62 and 63 from the lubricating oil holes 66c, a cancel room 60b is secured in the canceller 68, and the cancel room 60b The oil that overflows from the lubricating oil hole 66c or the canceling oil hole 66d is taken in to oppose the centrifugal oil pressure of the working oil in the working oil chamber 60a. Therefore, a structure is required in which lubricating oil is sent from inside the cancel chamber 60b to the clutch plates 62 and 63 shielded from the lubricating oil holes 66c by the canceller 68.

  In order to allow the lubricating oil overflowing from the lubricating oil passage 66c to reach the clutch plates 62 and 63, a part of the inner peripheral edge of the vertical plate portion 68a of the canceller 68 in contact with the outer peripheral surface of the central boss portion 61a of the clutch case 61. A notch 68d is provided on the vertical lubricating oil guide plate 69, and a radial oil groove 69a is formed in the vertical lubricating oil guide plate 69 as shown in FIGS. 10 and 11, and the cutout 68d and the oil groove 69a The oil in the canceller 68 is caused to flow out to the portion of the clutch space 60 where the clutch plates 62 and 63 are disposed outside the canceller 68 in the internal space of the clutch case 60. Thus, even if the cancel chamber 66a is provided radially inside the clutch plates 62 and 63, lubricating oil can be sufficiently supplied to the clutch plates 62 and 63.

Reference Signs List 50 hydraulic pump set 50a first hydraulic pump 50b second hydraulic pump 51 oil passage pipe member 52 cover plate 52a suction oil passage 52b discharge oil passage 53 pump block 53a (secondary) suction oil passage 53b hydraulic oil supply oil passage 54 oil Road block 54a Return oil path 54b Discharge oil path 54c Communication oil path 54d Hydraulic oil supply oil path 55 Unloading on-off valve 56 Check valve

Claims (3)

In a hydraulic pump unit for supplying clutch hydraulic oil, which is a combination of a dual first hydraulic pump and a second hydraulic pump driven simultaneously by a power source,
A first chamber formed in a main housing, and a second chamber formed by the main housing and a lid closing an opening of the main housing, and adjacent to the first chamber via a partition, A configuration in which the first hydraulic pump and the second hydraulic pump are housed in one chamber, and a hydraulic clutch is housed in the second chamber,
The working oil chamber of the hydraulic clutch to, regardless of the rotation speed of the animal power source, via an oil passage which is bored in the lid member and the main housing, to supply the discharge oil from said first hydraulic pump,
When the number of revolutions of the power source is less than a predetermined value, the discharge oil from the second hydraulic pump is discharged from the first hydraulic pump through an oil passage formed in the main housing and the lid . To join
When the number of revolutions of the power source is equal to or higher than a predetermined value, the discharge oil from the second hydraulic pump is supplied to the suction port of the first hydraulic pump via an oil passage formed in the main housing and the lid . Characterized by being configured to return
Hydraulic pump unit for supplying clutch hydraulic oil. Extending from the discharge port of the first hydraulic pump, a hydraulic oil supply passage towards the hydraulic oil chamber of the hydraulic clutch,
An on-off valve that is opened and closed by a controller based on the detection of the rotation speed of the power source,
A communication oil passage connecting the discharge port of the second hydraulic pump and the hydraulic oil supply oil passage to an inlet port of the on-off valve;
A return oil passage from an outlet port of the on-off valve to a suction port of the second hydraulic pump;
Providing a suction oil passage that communicates between the suction ports of the first hydraulic pump and the second hydraulic pump,
The on-off valve is closed when the number of revolutions of the power source is less than a predetermined value, and the oil from the discharge port of the second hydraulic pump is supplied to the hydraulic oil supply oil path via the communication oil path. And join
The on-off valve is opened when the number of revolutions of the power source is equal to or higher than a predetermined value, and the oil from the discharge port of the second hydraulic pump to the communication oil passage is transferred from the inlet port to the outlet port. Passing through the return oil passage, the suction port of the second hydraulic pump, and the suction oil passage to return to the suction port of the first hydraulic pump.
The hydraulic pump unit for supplying clutch hydraulic oil according to claim 1. A check valve is provided between the communication oil passage and the hydraulic oil supply oil passage, which allows only oil flow from the communication oil passage to the hydraulic oil supply oil passage when the on-off valve is closed. Characterized by the fact that
The hydraulic pump unit for supplying clutch hydraulic oil according to claim 2.

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