JPH10331948A - Transmission with auxiliary transmission gear - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transmission excellent in assemblage of an auxiliary transmission gear and a charging pump out of which at least the auxiliary transmission gear can be miniaturized. SOLUTION: An auxiliary transmission gear D is disposed inside an opening jointed to an engine housing, and a main transmission gear is disposed in a transmission housing on the opposite side to an engine, with the auxiliary transmission gear D placed in between. The auxiliary transmission gear D has integral unit structure formed by disposing gear type shift mechanism in integrally connected first and second cases 11, 12, and is fixed into the opening as it is integral unit structure. A transmission input shaft 5 protruded from the first case is connected to an output shaft of the engine. A charging pump 90 is disposed being coaxially connected to a pump shaft connecting member disposed in the first and second cases 11, 12, and pump driving force transmission mechanism for transmitting the rotation of a transmission input shaft to the pump shaft connecting member 38 is provided in the first and second cases 11, 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission having an auxiliary transmission, and more particularly, to a transmission housing in which an auxiliary transmission is provided inside an opening which is joined to a housing of a prime mover (engine, etc.). Further, the present invention relates to a transmission having a configuration in which a main transmission is disposed on the rear side.

[0002]

2. Description of the Related Art Various types of transmissions having an auxiliary transmission have been proposed and put into practical use. As an example, there is a transmission disclosed in Japanese Patent Publication No. 4-1218. In this transmission, a fluid coupling connected to an engine output shaft, a V-belt type continuously variable transmission mechanism (main transmission) connected to an output side of the fluid coupling, and an output side of the continuously variable transmission mechanism And a connected auxiliary transmission. In this transmission, both the main transmission and the auxiliary transmission are constructed by sequentially incorporating components in a transmission housing.

[0003]

By the way, the transmission having the main transmission and the auxiliary transmission as described above has the same structure as the transmission disclosed in the above-mentioned publication except that both transmissions are separately formed. In addition, it is general that they are integrally incorporated in a housing. For this reason, it is necessary to incorporate the components constituting the main transmission into the housing and also incorporate the components constituting the auxiliary transmission into the housing, which tends to cause a problem in assemblability. In addition, since both transmissions are incorporated in the same housing, the size of the housing is determined by the larger transmission, and even if one transmission can be made compact, the size of the housing is large. It is necessary to use large parts so that the transmission can be arranged, and there is a problem that the size of the entire transmission increases.

Further, a charge pump for producing lubrication of the transmission and control hydraulic pressure is generally incorporated in the transmission. However, it is also necessary to incorporate drive system components of the charge pump and the charge pump itself in the housing. Yes, there is a problem that the assembling operation is more difficult.

The present invention has been made in view of the above problems, and has as its object to provide a transmission excellent in assemblability, and in particular, to provide excellent assemblability of an auxiliary transmission and a charge pump, and at least to make the auxiliary transmission compact. It is an object of the present invention to provide an improved transmission.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, a transmission according to the present invention has a transmission housing having an opening formed therein for connection with a motor (eg, engine) housing. , An auxiliary transmission is disposed inside, and a main transmission is disposed in a transmission housing opposite to the prime mover with the auxiliary transmission interposed therebetween. The first and second auxiliary transmissions are integrally connected.
A transmission having a unitary structure in which a gear-type transmission mechanism is disposed in a case, which is disposed inside the opening with this integral unit structure, is fixed in the transmission housing, and further projects from the first case. The motor input shaft is configured to be connected to the output shaft of the prime mover. Further, a pump shaft connecting member rotatably disposed on a parallel shaft disposed apart from the transmission input shaft in the first and second cases in an integrally connected state, and a pump shaft connecting member. And a pump for transmitting transmission input shaft rotation to a pump shaft connecting member in the first and second cases in an integrally connected state with a charge pump coupled coaxially with the first or second case. A driving force transmission mechanism.

In the case of the transmission configured as described above,
Since the gear-type transmission mechanism is disposed in the first and second cases to constitute the auxiliary transmission having an integral unit structure, the main transmission is incorporated in the transmission housing from the flywheel opening side. The mounting of the auxiliary transmission is completed only by assembling the auxiliary transmission with the integral unit structure as it is. For this reason, the assemblability of the auxiliary transmission is improved. Further, since the charge pump drive system and the charge pump are also incorporated in the auxiliary transmission device integrated as described above, the assembly of the charge pump is completed only by installing the auxiliary transmission device.

A gear-type transmission mechanism constituting the auxiliary transmission is constituted by a plurality of planetary gear trains arranged in parallel in the axial direction and predetermined elements of the planetary gear trains (for example, as shown in FIG. The clutch comprises a clutch for releasably connecting the first sun gear and the second sun gear) and a brake for fixedly holding a predetermined element (for example, a second ring gear as shown in FIG. 5) of the planetary gear train. It is preferable that the brake is arranged along the inner peripheral surface of the two cases, and that the predetermined element is engaged with the second case and fixedly held by the brake.

[0009] Since the auxiliary transmission is provided in the transmission housing (in the opening) in the form of an integrated unit, the dimensions can be set without being affected by the size of the main transmission. For this reason, it is easy to reduce the size of the planetary gear train, the clutch, and the brake that constitute the auxiliary transmission, and make the entire auxiliary transmission smaller and more compact.

Further, a pump driving force transmitting mechanism is provided with a driving member (a sprocket or a pulley) connected to an input shaft of a transmission and a driven member (a sprocket or a pulley) connected and coaxially with a pump shaft connecting member. ) And a wrapping power transmitting member (chain or belt) bridged between the driving and driven members, wherein the driving member and the driven member are the first member.
It is preferable that the case is configured to be rotatably supported by the case.

[0011] According to this structure, the charge pump has a large degree of freedom in the arrangement position. For example, the gear pump and the charge pump constituting the auxiliary transmission are arranged so as to overlap in the axial direction. It is possible to reduce the size of the transmission in the axial direction. Also, by supporting both the driving and driven members rotatably by the first case,
By increasing the accuracy of the distance between the shafts of the two members, it is possible to reduce errors in mounting chains, belts, and the like.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows the entire configuration of a continuously variable transmission including an auxiliary transmission according to a preferred embodiment of the present invention.
4 to FIG.

[0013]

[Structure of the Transmission] As can be seen from the structure of the continuously variable transmission shown in FIGS. 1 to 4 and the skeleton diagram showing the power transmission path in FIG. 5, this transmission is used as an FR drive system, and A torque damper 2 is mounted on the output shaft 1 of the engine E provided.
And is extended rearward. This continuously variable transmission is a so-called hydromechanical continuously variable transmission, and includes a mechanical transmission unit D (auxiliary transmission) and a hydrostatic continuously variable transmission unit H (main transmission).
Are configured in combination. The hydrostatic continuously variable transmission unit H includes a variable swash plate type hydraulic pump P
1, a control unit panel C, and a variable swash plate type hydraulic motor M. As is apparent from FIG. 1, from the engine output shaft side, a mechanical transmission unit D, a hydraulic pump P, a control unit panel C, a hydraulic motor M And extend in the longitudinal direction of the vehicle body in this order.

In this continuously variable transmission, a mechanical transmission unit D and a hydraulic pump P are disposed in a first housing 10 joined to the rear end face of the engine. The second housing 14 is joined to the front surface of the control unit panel C, and the hydraulic motor M is provided inside the second housing 14.

First, as can be clearly understood from the skeleton diagram of FIG. 5, the mechanical transmission unit D corresponding to the auxiliary transmission according to the present invention includes first and second planetary gear trains 31, 32 (these are first and second sun gears 31s, 32s, first and second pinions, first and second carriers 31c, 32c, and first
And the second ring gears 31r and 32r).
Is configured. The unit D functions as a power split mechanism, has a transmission input shaft 5 connected to the torque damper 2, and is entirely disposed and surrounded by the first and second cases 11, 12 to form an integral unit. It has become.

The transmission input shaft 5 projects forward from the first case 11, is connected to the torque damper 2, is connected to the first sun gear 31s via the lock-up clutch 33, and is directly connected to the second sun gear 32s. The first and second carriers 31c and 32c are directly connected to each other, and the first ring gear 31r is connected and fixedly held to the control unit panel C,
The second ring gear 32r is directly connected to the cylinder 40 of the hydraulic pump. The second ring gear 32r (and the pump cylinder 40) can be fixedly held by a lock-up brake 34. Also, the first sun gear 31
The transmission output shaft 6 is connected to s. In the space surrounded by the first and second cases 11 and 12,
A sprocket 35 that is integrally connected to the transmission input shaft 5 is attached, and is configured to drive a charge pump via a chain.
It will be described later.

The hydraulic pump P has a pump cylinder 40 directly connected to the second ring gear 32r and rotatably slidably in contact with a side surface of the control unit panel C, and an annular arrangement surrounding the rotating shaft of the pump cylinder 40. A plurality of pump plungers 41 slidably fitted and inserted into a plurality of cylinder holes 40a formed by the above, and a shoe 42 slidably attached to the tip of each pump plunger 41 so as to slidably abut. And a swingable pump swash plate 43.

The pump swash plate 43 has trunnion portions 43a on both sides in the width direction. The trunnion portions 43a are formed on a curved bearing surface 13a formed on the pump cover 13 by races 44a and rollers 44b.
And is swingable about a pump swing axis Op that extends horizontally (extends perpendicularly to the paper) at right angles to the pump rotation axis. In addition,
Since the race 44a is provided on the curved bearing surface 13a in this manner, the surface heat treatment of the curved bearing surface 13a is unnecessary. However, the surface hardness of the curved bearing surface 13a may be increased by performing surface heat treatment, and the race 44a may not be required.

Below the hydraulic pump P, a pump swash plate servo 45 is provided which is supported by the control unit panel C and extends forward. A servo piston 45a is fixed to a servo cylinder 45b fixed to the control unit panel C. Move back and forth. The tip of the servo piston 45a is the pump swash plate 43.
Is connected via a link member 46 to the lower end of the pump swash plate 43 in accordance with the expansion and contraction movement of the servo piston 45a.
Can be swung about the pump swing axis Op.

The swing angle α of the pump swash plate 43 (this is referred to as the pump swash plate angle) is, as shown in FIG. It is possible to swing between a swash plate angle α = 0) and predetermined left and right maximum tilt positions (α = αR (MAX), αF (MAX)) tilted back and forth. Plunger 4 when pump cylinder 40 is rotated by
One reciprocating stroke changes. Even if the pump cylinder 40 is rotationally driven in the upright position, the reciprocating stroke is zero and the pump discharge oil amount is zero, and the reciprocating stroke increases as the swing angle increases toward the maximum tilt position, and the pump discharges. The amount increases. The discharge direction is reversed depending on whether the vehicle is inclined forward or backward, and the forward / backward direction of the vehicle is determined by the inclined direction.

The control unit panel C has a control panel body 50 located between the hydraulic pump P and the hydraulic motor M, and an oil passage 51 formed in the control panel body 50 (a pair of oil passages 51 as described later). ) Constitute a closed hydraulic circuit for connecting the hydraulic pump P and the hydraulic motor M. A pump cylinder 40 and a motor cylinder 60 are rotatably slidably disposed on front and rear side surfaces of the control panel body 50. Further, as described later, various control oil passages connected to a high-pressure relief valve and the like are also formed in the control panel body 50. Pump swash plate servo 45
Below, a control valve unit V is disposed,
It is appropriately connected to an oil passage in the control panel body 50.

The hydraulic motor M has a motor cylinder 60 coaxially connected to the transmission output shaft 6 and disposed on the rear side of the control unit panel C so as to be rotatably slidable. A plurality of motor plungers 61 slidably fitted and inserted into a plurality of cylinder holes 60a formed in a surrounding annular arrangement, and a shoe 62 slidably attached to the tip of each motor plunger 61 are slidable. And a swash plate 63 that can be oscillated variably.

The motor swash plate 43 also has trunnion portions 63a on both sides in the width direction. The trunnion portions 63a are formed on a curved bearing surface 15a formed on the motor cover 15 by races 64a and rollers 64b.
, And can swing about a motor swing axis Om that extends horizontally (extends perpendicularly to the paper) at right angles to the motor rotation shaft (and the transmission output shaft 6). In this case, the use of the race 64a also eliminates the need for the surface heat treatment of the curved bearing surface 15a. However, the heat treatment may be performed to eliminate the race.

A motor swash plate servo 65 which is supported by the control unit panel C and extends rearward is provided below the hydraulic motor M. A servo piston 65a is fixed to a servo cylinder 65b fixed to the control unit panel C. Move back and forth. The tip of the servo piston 65a is a motor swash plate 63.
Is connected via a link member 66 to the lower end of the motor swash plate 63 in accordance with the expansion and contraction movement of the servo piston 65a.
Can be oscillated about the motor oscillating axis Om.

The swing angle β of the motor swash plate 63 (referred to as the motor swash plate angle) is, as shown in FIG. 1, an upright position orthogonal to the motor rotation shaft (and the transmission output shaft 6). The swash plate angle β = 0) and the maximum inclination position (β = β (MAX)) in which the upper end swings forward, whereby the motor cylinder 60 is rotated. , The reciprocating stroke of the motor plunger 61 changes. When a predetermined operating oil pressure is acting from the hydraulic pump P, the motor cylinder 6
0 is held stationary, and the rotation of the motor cylinder 60 increases as the swing angle β decreases from the maximum tilt position (provided that the supply amount of hydraulic oil from the hydraulic pump P is constant). It should be noted that the motor swash plate 63 only swings counterclockwise from the upright position in the figure.

At the rear end of the transmission output shaft 6, a coupling member 6a is mounted.
The transmission output shaft 6 is connected to the propeller shaft via a, and the driving force is transmitted to the rear wheels. As shown in FIG. 4, a parking brake gear 8 is mounted near the rear end of the transmission output shaft 6.

[0027]

[Operation of Transmission] The operation of the continuously variable transmission having the above configuration will be described. When the engine E is driven, the engine output is transmitted from the output shaft 1 to the transmission via the torque damper 2, and the transmission input shaft 5 and the second sun gear 32 s are driven to rotate at the same speed as the engine output shaft 1. You. At this time, the lock-up clutch 33 and the lock-up brake 34 are released. When the second sun gear 32s is rotationally driven, the engine power is divided and transmitted to the motor cylinder 40 and the transmission output shaft 6 via the first and second planetary gear trains 31 and 32.

Since such power division differs depending on the swash plate angles of the hydraulic pump P and the hydraulic motor M, the relationship between the swash plate angles α and β and the total speed ratio e of the transmission is shown in FIG. This will be described with reference to FIG. The total speed ratio e is the ratio between the input and output rotational speeds of the transmission, and is obtained by equation (1). The vertical axis in FIG. 6 represents the pump and motor swash plate angles, with respect to the pump swash plate angle, the plus side means rightward swing, the minus side means leftward swing, and the motor swash plate angle is shown on the plus side. ing. The horizontal axis represents the total speed ratio e, with the plus side representing the speed ratio in the forward direction and the minus side representing the speed ratio in the reverse direction. Further, in FIG. 6, the solid line indicates the pump swash plate angle, and the broken line indicates the motor swash plate angle.

[0029]

(1) Total speed ratio e = (No) / (Ni) (1) where Ni: rotation speed of transmission input shaft 5 No: rotation speed of transmission output shaft 6

Here, the pump swash plate 43 is in the upright position (α =
0) and the motor swash plate 63 is at the maximum swing position (β = β (M
AX)), the pump cylinder 40 is freely rotatable and discharge is zero, and the motor cylinder 60 is hydraulically locked and fixedly held because there is no supply oil from the hydraulic pump P. Therefore, the motor cylinder 60
The first sun gear 31s directly connected to the first ring gear 31s is fixed, and the first ring gear 31r is always fixed.
The carriers 31c and 32c are also fixed. However, the rotation of the second sun gear 32s driven by the engine is transmitted to the pump cylinder 40 via the pinion of the second planetary gear train 32 and the second ring gear 32r, and the pump cylinder 40 rotates freely.
The engine output is consumed idling and is not transmitted to the transmission output shaft 6 (ie, the rear wheels). This state is the state indicated by the vertical line a in FIG. 6, the total speed ratio e = 0, and the transmission is in the neutral state.

However, this neutral state is a neutral state which is set when the shift lever (shift lever operated by the driver in the driver's seat) is in the driving range such as the D or R range. When the shift lever is in the P or N range position, the motor swash plate angle β is set to 0, the motor cylinder 60 is also made free to rotate, and control for creating a neutral state is performed.

When the pump swash plate 43 is swung to the right in this state, hydraulic oil is started to be discharged from the hydraulic pump 24 in response to the swing, and the discharged hydraulic oil is supplied to the hydraulic motor M and the hydraulic oil is supplied to the hydraulic motor M. The motor cylinder 60 of the motor M and the transmission output shaft 6 connected thereto are rotationally driven. The rotational driving force at this time is transmitted from the transmission output shaft 6 to the rear wheels via a propeller shaft (not shown), and the rear wheels are driven in the forward direction.

The rotational speed of the transmission output shaft 6 increases as the pump swash plate angle α increases, and this is the maximum swash plate angle α.
When F (MAX) is reached, the state shown by the vertical line b in FIG. 6 is obtained. Therefore, the overall speed ratio e increases from zero (vertical line a) to e1 (vertical line b). However, as the rotation of the transmission output shaft 6 increases, the mechanical power transmission via the mechanical transmission unit D simultaneously increases, and the action of the planetary gear train constituting the mechanical transmission unit D correspondingly increases. Thus, the rotation of the pump cylinder 40 decreases.

When the pump swash plate angle becomes the maximum swash plate angle αF (MAX) (when the state of the vertical line b is reached), the motor swash plate angle β
Is swung so as to gradually decrease from the maximum angle. As a result, the rotation speed of the motor cylinder 60 (transmission output shaft 6) further increases from the state of the vertical line b, and becomes the maximum when the motor swash plate angle β becomes zero (the upright position) (the vertical line d). State at this time, and becomes the total speed ratio e3).

Here, the gear ratio of the mechanical transmission unit D is set so that the total speed ratio e3 is larger than 1.0 (the reduction ratio is smaller than 1.0), that is, in an overdrive state. I have. The gear ratio is set so that the total gear ratio e2 = 1.0 at the time before the motor swash plate angle β reaches the maximum angle, that is, at the time indicated by the vertical line c in FIG. Thus, the total speed ratio e2
= 1.0, the transmission input shaft 5 and the transmission output shaft 6 rotate at the same speed. Therefore, the lock-up clutch 33 is engaged to prevent the power transmission loss by the mechanical transmission unit D, and to transmit the power. It is designed to improve efficiency.

Further, as described above, as the rotational speed of the transmission output shaft 6 increases, the amount of mechanical power transmitted via the mechanical transmission unit D increases, and the rotation of the pump cylinder 40 increases. The gear ratio of the mechanical transmission unit D4 is set so that the rotation of the pump cylinder 40 becomes zero when the motor swash plate angle β decreases to zero (the upright position). When the motor swash plate angle β becomes zero (upright position), the motor cylinder 60 is in a freely rotatable state, and the pump cylinder 40 is in a hydraulic lock state and is held stationary. Therefore, in this state (the state of the vertical line d), only mechanical power transmission is theoretically performed by the mechanical transmission unit D (there is no transmission loss and the transmission efficiency is 10%).
0%). However, in practice, transmission loss due to oil leakage or the like occurs. In this state, the lock-up brake 34 is engaged to forcibly prevent the rotation of the pump cylinder 40, and control is performed to improve the power transmission efficiency. It has become.

On the other hand, when the pump swash plate 43 is swung to the left from the state of the vertical line a, the hydraulic oil is discharged from the hydraulic pump P in the hydraulic closed circuit in the opposite direction. For this reason,
By the supply of the hydraulic oil, the motor cylinder 60 of the hydraulic motor M is driven in the reverse direction (reverse direction). The rotation speed of the motor cylinder 60 increases as the pump swash plate angle α increases. When the rotation speed of the motor cylinder 60 reaches the maximum swash plate angle αR (MAX), a state shown by a vertical line f in FIG. 6 is obtained. Therefore, the overall speed ratio e changes from zero (vertical line a) to e4 (negative value). However, when the motor cylinder 60 rotates in this manner, mechanical power transmission via the mechanical transmission unit D is performed at the same time as described above.

[0038]

[Hydraulic Control Circuit] A hydraulic closed circuit for transmitting power in the above-mentioned hydraulic continuously variable transmission and a control hydraulic circuit system thereof will be briefly described with reference to FIG. In this figure, the hydraulic pump P and the hydraulic motor M are symbolized and represented, and a first oil passage 51a connecting one port Pb of the hydraulic pump P and one port Ma of the hydraulic motor M, and a hydraulic pump P The second oil passage 51b connecting the other port Pa and the other port Mb of the hydraulic motor M forms a hydraulic closed circuit 51.

As described above, the pump swash plate 43 of the hydraulic pump P can swing right and left around the upright position (neutral position). The sucked hydraulic oil is discharged from the port Pb,
The hydraulic motor M is supplied to the port Ma of the hydraulic motor M to rotate the hydraulic motor M in the forward direction. After the driving, the hydraulic oil is discharged from the port Mb, supplied to the port Pa, and circulated in the closed circuit 51. At this time, if the wheels are driven by the rotational drive of the hydraulic motor M, the oil pressure in the first oil passage 51a becomes high pressure corresponding to the driving force, and the oil pressure in the second oil passage 51b becomes low pressure. On the other hand, when the rotation of the wheels is decelerated by the engine braking action, such as during coasting, the oil pressure in the second oil passage 51b becomes a high pressure corresponding to the engine braking force, and the first oil passage 51a The oil pressure in the inside becomes low.

When the pump swash plate 43 is swung in the left direction (reverse direction), the flow of hydraulic oil is completely opposite to that described above, and the hydraulic motor is driven to rotate in the reverse direction. At this time, the hydraulic pressures in the first and second oil passages 51a and 51b also have an inverse relationship to the above.

As described above, the driving force is transmitted between the hydraulic pump and the motor, but the hydraulic oil circulated in the hydraulic closed circuit 51 generates heat in accordance with the power transmission, the oil temperature rises, and Some of the oil accumulates and part of the oil leaks into the tank through gaps in the plunger. Therefore, part of the hydraulic oil in the closed hydraulic circuit is replaced to cool, replenish, and clean (flushing) the hydraulic oil. It is supposed to do. for that reason,
The hydraulic oil in the oil tank 70 is supplied to the suction filter 7
A charge pump 90 for supplying the first line 100 via the first line 100 is provided. Note that the charge pump 90
It is directly driven by the engine E via a chain hung on the sprocket 35 shown in FIG. 2 and discharges both hydraulic oils in proportion to the engine speed.

From the charge pump 90 to the first line 101
Is adjusted by the regulator valve 73 to a predetermined line pressure PL. First line 10
1 is connected to the illustrated pump servo control valve 74 and motor servo control valve 74, and the line pressure PL is supplied to both valves. The pump servo control valve 74 controls the supply of the line pressure PL to the pump swash plate servo 45, and controls the pump swash plate angle. Similarly, the motor servo control valve 75 controls the supply of the line pressure PL to the motor swash plate servo 65 to control the motor swash plate angle.

On the other hand, the hydraulic oil that has passed through the regulator valve 73 flows to the second line 102, is branched, and reaches the check valves 76a and 76b. Check valve 76
a, 76b are the third lines 103a, 103
3b, the hydraulic oil in the second line 102 communicates with the first oil passage 51a and the second oil passage 51b, respectively.
The hydraulic oil is supplied into the low-pressure side oil passage of the first and second oil passages 51a and 51b, whereby the hydraulic oil is supplied into the hydraulic closed circuit 51.

The third lines 103a and 103b are also connected to a shuttle valve 79, and the lower pressure side of the first and second oil passages 51a and 51b is connected to the fourth line 104 via the shuttle valve 78. The pressure is regulated by the low pressure relief valve 80. For this reason, the oil pressure in the low pressure side oil passage of the first and second oil passages 51a and 51b is adjusted to a predetermined low pressure by the low pressure relief valve 80. At the same time, as described above, the check valve 76
The hydraulic oil in the closed circuit 51 is discharged from the low-pressure relief valve 80 to the tank in accordance with the supply oil supplied through the hydraulic fluids a and 76b, and a part of the hydraulic oil in the hydraulic closed circuit is replaced by the hydraulic oil. Cooling, replenishing, flushing, etc.

The first oil passage 51a and the second oil passage 51b are further connected to high-pressure relief valves 74, 77 via fifth and sixth lines 105, 106, respectively. , 51b are set. Although not shown here, a valve for controlling the operation of the lock-up clutch 33 and the lock-up brake 34 is also provided. As shown in FIG. The oil is supplied to the lock-up clutch 33 and the lock-up brake 34 via a connecting pipe 95 connecting the first case 11 and an oil passage 96 formed in the first case 11 connected to the connecting pipe 95. A control valve unit V is composed of the various valves described above, and is disposed below the pump swash plate servo 45 as shown in FIGS.

A pump sliding surface 52 (see FIG. 3) where the pump cylinder 40 slides and a motor sliding surface 53 (see FIGS. 4 and 8) where the motor cylinder 60 slides are formed on both front and rear sides of the control panel body 50. , These two sliding contact surfaces 52, 53
Are formed ports Pa and Pb of the pump P and ports Ma and Mb of the motor M. These ports Pa and Mb
And a second oil passage 51b connecting the port Pb and Ma are formed penetrating the control panel body 50 back and forth. These first oil passage 51a and second oil passage 51
As shown in FIG. 8, the fifth line 105 and the sixth line 106 for guiding the hydraulic pressure b to the high-pressure relief valves 77 and 78 are formed by drill holes extending upward from the lower end surface of the control panel body 50. ing. The high-pressure relief valves 77 and 78 are attached to the rear end face of the control panel body 50, and the high-pressure relief valves 7 and 78
7 and 78 are connected to the fifth and sixth lines 105 and 106, and the high pressure in the first and second oil passages is set. Further, third lines 103a and 103b connected to the check valves 76a and 76b and the shuttle valve 79 are also formed in the control panel body 50, and are connected to the control valve unit V.

The transmission mechanism described above is disposed inside the first housing 10 joined to the rear end surface of the engine, the second housing 14 surrounding the motor M and joined to the control unit panel C, and the like. This assembly configuration will be described below.

[0048]

[Structure of charge pump drive unit]
FIG. 8 shows a view from the input shaft side before being attached to the engine. A flywheel opening 10b is formed in the first housing 10 so as to be surrounded by a joint surface 10a with the engine flywheel housing. In the flywheel opening 10b, a mechanical transmission unit (auxiliary transmission) D is fixed by bolts 12a. Has been established. As described above, the mechanical transmission unit D is integrally formed by connecting the first and second cases 11 and 12 with the bolts 11a.
The first housing 10 is connected to the first housing 10 by 2a.

The mechanical transmission unit D thus attached to the first housing 10 is shown by arrows IX-IX in FIG.
FIG. 9 is a cross-sectional view taken along the line. As can be seen from this figure, the drive sprocket 35 spline-coupled to the transmission input shaft 5 at the hub 35a is rotatably supported with the transmission input shaft 5 by the pairing 5a with respect to the first case 11. . In addition, bearing 3
A driven sprocket 37 rotatably supported by the first case 11 by the first sprocket 7a is disposed so as to overlap the driving sprocket 35 in the axial direction and at a predetermined distance in the radial direction. 36 are passed over. Therefore, when the transmission input shaft 5 is rotationally driven by the engine, the driven sprocket 37 is also rotationally driven via the chain.

Here, since both sprockets 35 and 37 are rotatably supported by the first case 10, the radial distance between the sprockets 35 and 37, that is, the accuracy of the distance between the shafts can be increased. Accurate and quiet power transmission is possible by increasing the mounting accuracy of the chain 36. Further, the driving sprocket 35 and the bearing 5a for supporting the rotation thereof substantially overlap in the radial direction, and the driven sprocket 37 and the bearing 37a for supporting the rotation thereof substantially overlap in the radial direction. As a result, the force acting from the sprockets 35 and 37 is
Acts on almost the center in the width direction of the sprockets a, 37a, so that an unbalanced load does not act on the bearings, and the lateral run-out of the sprockets 35, 37 can be suppressed.

As described above, the first and second cases 11, 1
Transmission unit D which is an integrated unit by combining
FIG. 10 is a view of only the charge pump 90 seen from the rear side in FIG. 8. As can be seen from this figure, a charge pump 90 is connected to the outer surface (rear surface) of the second case 12 by bolts 90 a. As can be clearly seen from the figure, the charge pump 90
Is located at a position axially overlapping with the planetary gear trains disposed in the first and second cases 11 and 12 and is located apart from the radial direction. For this reason, the radial dimension is required and the shape projects slightly obliquely downward as shown in the figure. However, the axial dimension can be reduced, and the overall length of the transmission can be reduced.

The charge pump 90 is composed of, for example, a gear pump, and its drive shaft is connected to the driven sprocket 37 via a pump shaft connecting member 38. For this reason,
When the engine is driven, the charge pump 90 is driven at a rotation speed proportional to the rotation of the engine. As shown in FIG. 10, the pump 90 has a suction port 93 and a discharge port 91, and the suction port 93 is connected to a suction pipe (not shown) having a suction filter and the like, and is connected to the oil pan 19.
Inhale the hydraulic oil inside. On the other hand, the discharge port 91 is
As shown in (5), it is connected to the control valve unit V via the discharge connection pipe 92. Therefore, the discharge oil of the charge pump 90 is directly supplied to the control valve unit V via the discharge connection pipe 92.

[0053]

[Overall Assembling Structure] The transmission mechanism described above is disposed inside the first housing 10 joined to the rear end surface of the engine, the second housing 14 joined to the control unit panel C surrounding the motor M, and the like. . This assembly configuration will be described below.

First, the first housing 10 is mounted with its rear end face joined to the front side of the control unit panel C (control panel body 50), and the hydraulic pump P is disposed in the rear space of the first housing 10. The pump cover 13 is fastened by bolts 17 to cover this rear space. FIG. 11 shows a view in which only the first housing 10 is viewed from the joint surface 10a side with the engine, and the pump cover 13 is joined and attached to a pump cover joint surface 10d formed in the first housing 10. .

As described above, the pump cover 13 has the bearing curved surfaces 13a on the left and right sides, and the trunnion portion 43a of the pump is swingably supported on the bearing curved surfaces 13a via the races 44a and the rollers 44b. In this case, the reaction force of the pump plunger 41 in the hydraulic pump P acts on the trunnion portion 43a. The pump cover 13 supporting the trunnion portion 43a is sandwiched between the first housing 10 by the bolt 17 and the control panel body 50. Is joined to. Therefore, this reaction force is received by the control panel body 50 from the pump cover 13 via the bolt 17, and does not act on the first housing 10. As can be seen from this, the control panel body 50 and the pump cover 1
3 is made of cast steel or the like because high strength and rigidity are required, but the first housing 10 is made of a normal aluminum casting,
Made from cast iron.

On the other hand, as described above, the mechanical transmission unit D is disposed in the space surrounded by the first and second cases 11 and 12 and has an integral structure. That is, the mechanical transmission unit D is disposed inside the first and second cases 1.
1 and 12 form an independent integrated unit in a closed state. As shown in FIG. 11, the first housing 10 is formed with a unit joining surface 10c for attaching the mechanical transmission unit D formed as an integrated unit as described above. As shown in FIGS. 1 and 2, the mechanical transmission unit D is located on the front side of the pump cover 13 and is fastened to the unit joining surface 10c of the first housing 10 by bolts 12a so as to cover the same.

Further, the second housing 14 is mounted so as to cover the rear side surface of the control panel body 50, and the motor M is mounted therein. Then, the motor cover 15 is attached to the rear end surface of the second housing 14 by fastening with bolts 18. Also in this case, the motor cover 15 that supports the motor trunnion portion 63a is
Is connected to the control panel body 50 with the second housing 14 interposed therebetween, and the reaction force of the motor plunger 61 is transmitted from the motor cover 15 via the bolt 18 to the control panel body 50.
And does not act on the second housing 14.
For this reason, the motor cover 15 is made of a material having high strength and rigidity such as cast steel, and the second housing 14 is also made of an aluminum casting, cast iron or the like.

Next, after the parking gear 8 is attached to the transmission output shaft 6 projecting rearward from the rear end of the second housing 14, the rear end cover 16 is attached, and a coupling is attached to the rear end of the transmission output shaft 6. The member 6a is attached. The first
An opening is formed in the lower surface of the housing 10, a valve support plate 57 is mounted in the opening with the control valve unit V mounted on the upper surface, and an oil pan 19 is further mounted to cover the entire opening.

The transmission configured as described above and having a shape extending in the front-rear axial direction is mounted by connecting the front end face of the first housing 10 to the engine flywheel housing. At this time, the transmission input shaft 5 is spline-engaged with the torque damper 2. Here, the engine is disposed at the front part (in the hood) of the vehicle, and the transmission coupled to the rear end of the engine is, as shown in FIG.
It is located in a floor tunnel 95 extending forward and backward at the center of the vehicle interior floor 91 in the vehicle width direction. In this case, the transmission is formed so as to extend forward and backward, so that the transmission can be easily disposed even in the floor tunnel 95 having a small cross section. In particular, since the pump swash plate and the motor swash plate servos 45 and 65 are disposed below the transmission, the projecting height of the floor member 93 forming the floor tunnel 95 is reduced and the width is reduced. The interior space of the vehicle can be widened.

[0060]

As described above, according to the present invention,
The auxiliary transmission arranged inside the opening of the transmission housing has an integral unit structure in which a gear-type transmission mechanism is arranged in first and second cases that are integrally coupled to each other. Since the transmission input shaft protruding from the first case is connected to the output shaft of the prime mover, the auxiliary transmission is integrally provided inside the opening and fixed in the transmission housing. After assembling to the unit state, it is only necessary to fix the unit in the transmission housing in the state of the integrated unit, and the assembling work can be made easy and simple.

Further, in the present invention, a pump shaft connecting member is disposed radially apart from the input shaft in the first and second cases in an integrally connected state, and connected coaxially with the pump shaft connecting member. And a pump driving force transmitting mechanism for transmitting the rotation of the transmission input shaft to the pump shaft connecting member in the first and second cases in an integrally connected state. Since the charge pump drive system and the charge pump are also incorporated in the auxiliary transmission device integrated as described above, the assembly of the charge pump is completed only by installing the auxiliary transmission device, and the assemblability is improved. very good.

A gear-type transmission mechanism constituting the auxiliary transmission is constituted by a plurality of planetary gear trains arranged in parallel in the axial direction, and a clutch for connecting predetermined elements of the planetary gear trains in a detachable manner. And a brake for fixedly holding a predetermined element of the planetary gear train. The brake is disposed along the inner peripheral surface of the second case, and the brake engages the predetermined element with the second case to fix and hold the predetermined element. It is preferable to configure. Since the auxiliary transmission is provided in the transmission housing (within the opening of the flywheel) with the unitary structure, the auxiliary transmission can be set without being affected by the size of the main transmission. It is easy to reduce the size of the planetary gear train, the clutch and the brake constituting the above-mentioned and make the whole auxiliary transmission device smaller and more compact.

Further, the pump driving force transmission mechanism is bridged between the driving member and the driving member which are connected and arranged on the transmission input shaft, the driven member which is connected and disposed coaxially with the pump shaft connecting member. And a driven power transmitting member, and the driving member and the driven member are preferably rotatably supported by the first case. With such a configuration, the position of the charge pump can be freely set. The degree is large, for example, the gear type transmission mechanism and the charge pump constituting the auxiliary transmission are disposed so as to overlap in the axial direction,
It is possible to reduce the size of the transmission in the axial direction.
In addition, since both the driving and driven members are rotatably supported by the first case, the accuracy of the distance between the two members can be increased, and the mounting error of the wrapping power transmission member can be reduced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing the overall configuration of a continuously variable transmission including an auxiliary transmission according to the present invention.

FIG. 2 is an enlarged sectional view showing a left portion of the continuously variable transmission of FIG. 1;

FIG. 3 is an enlarged sectional view showing a central portion of the continuously variable transmission shown in FIG. 1;

FIG. 4 is an enlarged sectional view showing a right side portion of the continuously variable transmission of FIG. 1;

FIG. 5 is a skeleton diagram showing a power transmission path configuration of the continuously variable transmission of FIG. 1;

6 is a graph showing a relationship between a swash plate angle of a hydraulic pump and a motor in the continuously variable transmission of FIG. 1 and an overall speed ratio.

FIG. 7 is a hydraulic control circuit diagram for performing hydraulic control in the continuously variable transmission of FIG. 1;

FIG. 8 is a side view of the continuously variable transmission of FIG. 1 as viewed from the engine side.

FIG. 9 is a cross-sectional view showing the continuously variable transmission shown in FIG. 8 along an arrow IX-IX.

FIG. 10 is a side view showing a mechanical transmission unit (auxiliary transmission) constituting the continuously variable transmission as viewed from the rear.

FIG. 11 is a side view of the first housing constituting the continuously variable transmission, as viewed from a joint surface side with an engine.

FIG. 12 is a cross-sectional view showing the continuously variable transmission shown in FIG. 1 along an arrow VIII-VIII.

[Explanation of symbols]

 Reference Signs List 1 engine output shaft 2 torque damper 5 transmission input shaft 6 transmission output shaft 10 first housing 13 pump cover 14 second housing 15 motor cover 17, 18 bolt 31, 32 planetary gear train 33 lock-up clutch 34 lock-up brake 40 pump Cylinder 43 Pump swash plate 45 Pump swash plate servo 50 Control plate body 51 Hydraulic closed circuit 60 Motor cylinder 63 Motor swash plate 65 Motor swash plate servo

Claims (3)

[Claims] 1. A transmission housing formed with an opening joined to a motor housing, an auxiliary transmission disposed inside the opening of the transmission housing, and an auxiliary transmission interposed therebetween. A main transmission disposed opposite to the prime mover and disposed in the transmission housing, wherein the auxiliary transmission includes a gear-type transmission mechanism in first and second cases integrally coupled. A transmission input shaft that is disposed inside the opening, fixed in the transmission housing, and protrudes from the first case. The transmission case is configured to be connected to an output shaft, and to rotate on a parallel shaft disposed radially away from the transmission input shaft in the first and second cases in an integrally connected state. A pump shaft connecting member freely arranged; a charge pump coaxially connected to the pump shaft connecting member and attached to the first or second case; And a pump driving force transmitting mechanism for transmitting the rotation of the transmission input shaft to the pump shaft connecting member in the two cases. 2. A clutch in which the gear-type transmission mechanism constituting the auxiliary transmission is connected to a plurality of planetary gear trains arranged in parallel in an axial direction, and predetermined elements of the planetary gear trains are detachably connected to each other. And a brake for fixedly holding a predetermined element of the planetary gear train, wherein the brake is disposed along an inner peripheral surface of the second case. A transmission equipped with the auxiliary transmission device. 3. The pump driving force transmission mechanism is disposed on the transmission input shaft and is integrally connected to a driving member that rotates integrally with the transmission input shaft and is coaxially connected to the pump shaft connecting member. A driven member and a wrapping power transmitting member such as a chain or a belt stretched between the driving and driven sprockets, wherein the driving member and the driven member are rotatably supported by the first case. A transmission comprising the auxiliary transmission according to claim 1.