JP2004036860A - Driving device for four-wheel drive vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a driving device for a four-wheel drive vehicle capable of securing the required discharge of an oil pump without enlarging the oil pump or newly providing a member for driving the oil pump. <P>SOLUTION: A driving gear 23 and a driven gear 26 for accelerating to transmit the rotation of a transfer input shaft 22 to an idle shaft 24 are provided between the idle shaft 24 and the transfer input shaft 22 to which power from an engine is inputted, and the oil pump 80 is provided on the axis of the idle shaft 24 and driven by the rotation of the idle shaft 24. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a drive device for a four-wheel drive vehicle, and more particularly to the technical field of a structure for mounting an oil pump on the drive device.
[0002]
[Prior art]
Generally, a four-wheel drive vehicle is provided with a transfer for distributing power generated by an engine to front and rear wheels. The transfer includes, for example, an input shaft that is arranged in the vehicle width direction and receives power from a front engine, an output shaft that extends perpendicularly to the input shaft and extends rearward of the vehicle body, and an interposition between the two shafts. And a case that accommodates the bevel gear mechanism and has a bearing portion that supports the output shaft.
[0003]
In such a case, the transfer may be provided with an oil pump that circulates lubricating oil for lubricating the gears and shafts in the transfer. For example, Japanese Patent Application Laid-Open No. 6-70458 discloses an arrangement in which a gear train is provided between a transfer shaft and a drive shaft of an oil pump, and the oil pump is driven by rotation of the transfer shaft. . However, in this case, the provision of a new drive system such as a gear train for driving the oil pump results in an increase in size and cost of the transfer.
[0004]
In order to eliminate the need for a gear train or the like, Japanese Patent Laying-Open No. 5-77543 discloses a device in which an oil pump is provided at one end of an output shaft and the oil pump is directly driven by the output shaft. .
[0005]
[Problems to be solved by the invention]
However, according to the technology disclosed in the above publication, the output shaft rotates at substantially the same rotation speed as the input shaft, so that the rotation speed of the oil pump is also limited to a relatively low rotation speed of the output shaft. In order to obtain the amount, the size of the pump must be increased, which hinders downsizing of the transfer.
[0006]
Further, for example, when the transfer is disposed on the rear side of the vehicle body with respect to the engine, the cooling air flowing in from the front of the vehicle body is obstructed by the engine, so that the temperature of the transfer tends to increase, and as a result, the oil temperature increases. Since the viscosity is reduced, it is necessary to effectively cool the oil with an oil cooler or the like. In particular, for example, when the output shaft must be arranged above the steering member extending in the vehicle width direction or the suspension cross member extending in the vehicle width direction due to the design of the vehicle body or the design of the steering system, the lower surface of the vehicle body Since the cooling effect of the cooling air passing through the side is reduced and the environment is placed in a very severe thermal environment, it is necessary to secure a sufficient discharge amount of the oil pump in order to cope with this.
[0007]
Therefore, the present invention provides a four-wheel drive vehicle that can ensure a required oil pump discharge amount without increasing the size of the oil pump and without newly providing a member for driving the oil pump. It is an object to provide a driving device.
[0008]
[Means for Solving the Problems]
That is, the invention according to claim 1 includes an input shaft arranged in a vehicle body width direction to receive power from a front engine, an output shaft orthogonal to the input shaft and extending rearward of the vehicle body, and the input shaft. Member having a power transmission shaft for transmitting power from the shaft to an output shaft, and a case for accommodating the power transmission shaft, wherein the output shaft extends in the vehicle width direction on a suspension cross member arranged in the vehicle width direction. An oil pump disposed on the case and provided with an oil pump for supplying lubricating oil to a predetermined portion in the case, wherein the input shaft and the power transmission shaft are provided. And a speed increasing means for transmitting the rotation of the input shaft to the power transmission shaft at an increased speed. The oil pump is provided on the axis of the power transmission shaft. Configured to be driven And said that you are.
[0009]
According to the present invention, since the oil pump is driven by the rotation of the power transmission shaft, it is necessary to newly provide members such as a gear train for transmitting power to the oil pump and shafts for supporting the gear train. There is no.
[0010]
In addition, since the rotation of the input shaft is transmitted to the power transmission shaft at an increased speed, the rotation of the oil pump is increased and the pump capacity is improved. That is, a required discharge amount can be secured without increasing the size of the oil pump, and a predetermined portion can be lubricated satisfactorily. Also, for example, if the lubricating oil is supplied to an oil cooler, the lubricating oil can be effectively cooled.
[0011]
According to a second aspect of the present invention, in the first aspect of the present invention, the input shaft and the power transmission shaft are disposed in parallel, and the speed increasing means is provided on an input shaft provided on the input shaft. And a transmission gear provided on the power transmission shaft and meshed with the input gear.
[0012]
According to the present invention, when power is input to the input shaft, the rotation of the input shaft always drives the power transmission shaft, and the oil pump always operates. Further, as described above, since the rotation of the input shaft is transmitted to the power transmission shaft at an increased speed, the oil pump operates effectively when the rotation of the input shaft is low.
[0013]
According to a third aspect of the present invention, in the first or second aspect, the oil pump is configured to be driven by a small-diameter shaft provided at one end of the power transmission shaft. It is characterized by having.
[0014]
According to the present invention, since the oil pump is driven by the small-diameter shaft provided at one end of the power transmission shaft, the oil pump can be made smaller than when the transmission shaft is directly connected to the oil pump. .
[0015]
By the way, lubricating oil is stored in the case. When the gear in the case is immersed in the lubricating oil, the lubricating oil is stirred when the gear rotates. In particular, when the output shaft is disposed above the steering member or the suspension cross member, the input shaft may be provided at a position lower than the output shaft. In this case, the input gear provided on the input shaft is used for lubricating oil. As a result, the agitation resistance tends to increase when the input gear rotates. As a result, the temperature of the lubricating oil tends to increase.
[0016]
Therefore, according to a fourth aspect of the present invention, in the first aspect of the present invention, there is provided an oil reservoir capable of storing a predetermined amount of lubricating oil below an input gear provided on an input shaft. Is provided so as to protrude downward from the lower part of the case, and the oil pump sucks lubricating oil from the oil reservoir.
[0017]
According to the present invention, a predetermined amount of lubricating oil is stored in the oil reservoir among required lubricating oil amounts determined according to the volume in the case, the number and size of gears, the critical oil temperature, and the like. Therefore, the upper surface of the lubricating oil stored in the case is lower than in the case where there is no oil reservoir protruding downward from the lower part of the case. That is, the depth at which the input gear is immersed in the lubricating oil is reduced, the agitation resistance is reduced, and the temperature rise of the lubricating oil is suppressed. In other words, the lubricating oil further contributes to the improvement of the cooling effect.
[0018]
On the other hand, even when the oil pump is operating, since the lubricating oil is circulated and diffused in the case, the upper surface of the lubricating oil is lowered, but the oil reservoir is provided at a low position. Thus, even when the oil level is low, the lubricating oil can be reliably sucked. In other words, if the lubricating oil is stored in the oil reservoir even in a small amount, since the lubricating oil can be circulated in the case, the required amount of lubricating oil can be reduced from the volume in the case, As a result, as described above, the depth at which the input gear is immersed in the lubricating oil is reduced, the stirring resistance is reduced, and the temperature rise of the lubricating oil is suppressed.
[0019]
According to a fifth aspect of the present invention, in the first aspect, an oil cooler for cooling the lubricating oil is provided, and the lubricating oil is supplied from the oil pump to the oil cooler. Is characterized by using a pipe, and the pipe is arranged in a space in the case.
[0020]
According to the present invention, the oil passage for supplying the lubricating oil from the oil pump to the oil cooler is configured by using the pipe, and the pipe is disposed in the space in the case. Thus, for example, there is no interference with devices arranged in the vicinity such as engine accessories, and the degree of freedom in layout of the peripheral devices increases. Further, when the peripheral devices become high in temperature, the peripheral devices are less susceptible to heat from them.
[0021]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described.
[0022]
FIG. 1 is a skeleton diagram showing a power transmission path of a four-wheel drive vehicle according to an embodiment of the present invention. Triangles in the figure represent bearings. This four-wheel drive vehicle is based on the configuration of an FF in which the front wheels are constantly driven by an engine 1 arranged horizontally in an engine room at the front of the vehicle body. The crankshaft 2 of the engine 1 extends in the width direction of the vehicle body, and a torque converter 3 is connected to the crankshaft 2 in series. An automatic transmission 6 of a transaxle 5 is connected in series to a turbine shaft 4 of the torque converter 3. An output shaft 7 of the automatic transmission 6 also extends in the vehicle width direction, and an output gear 8 is provided on the output shaft 7.
[0023]
A transaxle case 9 is connected to the left end of the engine 1. Transaxle case 9 includes case 9a of torque converter 3 and case 9b of automatic transmission 6. A front axle differential (front differential) 10 is accommodated in a transaxle case 9. A ring gear 12 is assembled to a differential case 11 of the front differential 10 and meshes with the output gear 8. Left and right front wheel drive shafts 14L, 14R extending in the vehicle width direction are connected to left and right pinion gears 13L, 13R in the differential case 11, respectively. Left and right front wheel axles 16L, 16R are connected to the respective drive shafts 14L, 14R via universal joints 15, 15, respectively. Left and right front wheels W, W (see FIG. 3) are connected to the axles 16L, 16R, respectively. The transaxle case 9 rotatably supports the differential case 11.
[0024]
A transfer case 21 is connected to a right side surface of the transaxle case 9. The transfer case 21 includes a front case 21a and a rear case 21b (see FIG. 2). The transfer case 21 rotatably supports the right end of the right front wheel drive shaft 14R. The transfer case 21 also rotatably supports a transfer input shaft 22 of the transfer 20. The transfer input shaft 22 is coaxially arranged around the right front wheel drive shaft 14R, and is connected to the right part of the front differential case 11. A drive gear 23 is mounted on the outer peripheral surface of the transfer input shaft 22.
[0025]
The transfer case 21 further rotatably supports the idle shaft 24 and the transfer output shaft 25. The idle shaft 24 extends in the vehicle width direction similarly to the front wheel drive shafts 14L and 14R, the transfer input shaft 22, and the like. The transfer output shaft 25 extends in the vehicle longitudinal direction orthogonal to the idle shaft 24. A driven gear 26 is attached to the idle shaft 24 and meshes with the drive gear 23. The idle shaft 24 has a hypoid-type ring gear 27, which meshes with a hypoid-type pinion gear 28 at the front end of the transfer output shaft 25. A propeller shaft 32 is connected to a rear end of the transfer output shaft 25 via a universal joint 31.
[0026]
A rear wheel side pinion shaft 33 is connected to a rear end of the propeller shaft 32. The pinion shaft 33 has a hypoid-type pinion gear 34, which meshes with a hypoid-type ring gear 37 mounted on a differential case 36 of a rear wheel differential (rear differential) 35. Left and right rear wheel drive shafts 39L and 39R extending in the vehicle width direction are connected to left and right pinion gears 38L and 38R in the rear differential case 36, respectively. Left and right rear wheel axles 41L, 41R are connected to the respective drive shafts 39L, 39R via universal joints 40, 40, respectively. Left and right rear wheels (not shown) are connected to the axles 41L and 41R, respectively. With the above configuration, the front wheels are constantly driven by the left and right front wheel drive shafts 14L and 14R, and the engine output is transmitted to the rear wheels via the transfer 20.
[0027]
Next, with reference to FIG. 3, a description will be given of a positional relationship with devices arranged around the transfer 20 and the like. The side indicated by reference numeral A in FIG. 3 is the front side of the vehicle body, and the engine 1 is placed laterally in the engine room X at the front part of the vehicle body as described above. The transfer 20 is disposed behind the engine 1 on the vehicle body rear side. The axial position of the transfer output shaft 25 of the transfer 20 is determined so that the output shaft 25 does not interfere with the steering steering rack 50 arranged in the width direction of the vehicle body. Have been higher. Hereinafter, this structure is appropriately referred to as a high mount structure. On the other hand, a structure in which the output shaft 25 is disposed below the steering rack 50 or the like is referred to as a low mount structure. From the right side of the steering rack 50, a steering shaft 50a extends toward the passenger compartment (see FIG. 4).
[0028]
Below the steering rack 50, a suspension cross member 51 extending in the vehicle width direction and supporting a front wheel suspension is disposed. Here, since the suspension cross member 51 has the transfer output shaft 25 located at a position higher than the steering rack 50, for example, a torii gate between the left and right ends in order to avoid interference with the transfer output shaft 25 as in the related art. There is no need to bend the shape, and it is almost flat. That is, in the low mount structure, when viewed from the front or rear of the vehicle body, the suspension cross member 51 is bent in a convex shape so as to bypass the output shaft 25 upward. Therefore, it becomes easy to bend by the external force in the left-right direction. On the other hand, in the high mount structure, the suspension cross member 51 does not need to be bent as described above, so that the suspension cross member 51 can be made almost flat, and there is almost no bending in the left-right direction. As a result, the lateral rigidity of the suspension cross member 51 is improved, and the steering stability is improved. In addition, the front frame 52, which is a structural material at the front of the vehicle body, extends in the longitudinal direction of the vehicle body on both left and right end surfaces of the engine 1, and its kick-up portion 52a has a reduced height of the steering rack 50. Can be bent more slowly. According to this, the rigidity against external force from the front of the vehicle body is improved.
[0029]
Further, as shown in FIG. 4, the transaxle 5 is disposed on the left side of the transfer 20. Although not shown, the engine 1 is provided with a large number of accessories. The engine 1 is of a rear exhaust type, and an exhaust manifold 60 is attached to a rear side surface of the engine 1. An exhaust gas purification device 61 is connected to a lower end of the manifold 60, and an end of the exhaust gas purification device 61 extends near the transfer 20 and is connected to an exhaust pipe 62. In this case, since the steering rack 50 is located relatively below as described above, the exhaust pipe 62 can be bent smoothly without passing through the steering rack 50 with a small angle. According to this, it is not necessary to bend at a sharp angle and pass below the rack 50 as in the related art, and there are effects such as a reduction in exhaust resistance.
[0030]
While many effects can be obtained in this manner, the transfer shaft 20 is located on the rear side of the vehicle body of the engine 1 so that even if the air permeability to the transfer 20 is poor, the output shaft 25 is connected to the steering rack 50 and the suspension cross member. Since the cooling air is provided above 51, the cooling effect of the cooling air passing below the vehicle body is reduced, and the thermal environment around the transfer, particularly around the transfer output shaft 25, becomes more severe.
[0031]
Further, as shown in FIG. 5, since the transfer output shaft 25 is located at a higher position than the transfer input shaft 22, it is necessary to sufficiently lubricate the bearings 29 and 30 of the transfer input shaft 22 and the hypoid pinion gear 28. It is conceivable to store the lubricating oil in the transfer case 20 up to the height of the transfer output shaft 25. However, the drive gear 23 agitates a large amount of the lubricating oil, and the lubricating oil generates heat and its temperature tends to rise. Problem arises.
[0032]
Therefore, in the present embodiment, an oil cooler 70 is provided directly above the bearings 29, 30 of the transfer output shaft 25 in the transfer case 20, and a lubricating oil is provided to the oil cooler 70, as shown in FIGS. Is provided coaxially with the idle shaft 24, the lubricating oil is supplied to the oil cooler 70 by the rotation of the idle shaft 24, and the lubricating oil cooled by the oil cooler 70 is supplied to the bearing 29. , 30 are supplied.
[0033]
That is, as shown in FIGS. 6 and 7, the oil pump 80 is a trochoid pump, and includes a rotary shaft 81 in which a hexagonal column-shaped end portion 81a is fitted into a hollow portion of the idle shaft 24, and a transfer case 20. , A pump case 82 provided with a recess 82 a on the side surface on the side of the idle shaft 24, a drive rotor 83 engaged with an end of the rotary shaft 81 opposite to the end 81 a, and a pump case 82, a driven rotor 84 rotatably fitted in the concave portion 82a and being rotationally driven by the drive rotor 83 in the concave portion 82a, a cover member 85 for closing a side surface of the pump case 82 on the idle shaft 24 side, and a pump case 82. A locking member 86 fixed in the concave portion 82a of the first member and a cover member 85 interposed between the locking member 86 and the cover member 85, and the cover member 85 is attached to the rotor 83 side. And a disc spring 87. The pump case 82 is provided with a lubricating oil intake oil passage 82b and a discharge oil passage 82c. According to this, when the rotation shaft 81 is driven by the rotation of the transfer input shaft 23 and rotates in the direction B, the drive rotor 83 rotates in the direction B and the driven rotor 84 is driven by the drive rotor 83 to move the driven rotor 84 in the direction B. At this time, when the volume of the oil chamber Y formed by the drive rotor 83 and the driven rotor 84 changes, the lubricating oil is sucked from the oil supply port 82b and discharged from the discharge port 82c. . In this case, the gear ratio between the drive gear 23 and the driven gear 26 is such that the rotation of the transfer input shaft 22 is transmitted to the idle shaft 24 at an increased speed. The rotating shaft 81 and the rotors 83 and 84 rotate at a higher speed than the input shaft.
[0034]
On the other hand, the oil cooler 70 is of a water-cooled type using cooling water as a coolant, and has a supply pipe 71 and a discharge pipe 72 for cooling water on its upper surface, and has a lubricating surface on its lower surface. An oil inlet 73 and an oil outlet 74 are provided. Although not described in detail, a number of fins cooled by cooling water are provided inside. Lubricating oil sucked from the suction port 73 passes between the fins to lubricate. The oil is cooled, and the cooled lubricating oil is discharged from the outlet 74.
[0035]
An oil pan 90 that can store a predetermined amount of lubricating oil is provided below the transfer case 20. A first oil passage 100 connecting the oil pan 90 and the oil pump 80 and a second oil passage 110 connecting the oil pump 80 and the oil cooler 70 use a pipe in the space inside the transfer case 20. It is provided.
[0036]
The first oil passage 100 is inserted into an oil passage 82b of a pump case 82 of the oil pump 80 and fixed to an inner wall of the case via a bracket (not shown), and a lower end of the first pipe member 101. And a strainer 102 attached to the
[0037]
The second oil passage 110 is inserted into the oil passage 82 c of the pump case 82 of the oil pump 80 and extends forward from the vehicle body, and extends upward from the tip of the second pipe member 111 and extends rearward from the vehicle body. And a third pipe member 112 that bends. These pipe members 111 and 112 are fixed to the inner wall of the case via a bracket (not shown). The second oil passage 110 is bored in the upper wall of the transfer case 20 and extends from the end of the pipe member 112 in the direction of the oil cooler 70, and is provided at the end of the passage 113. A second passage 114 communicating with the suction port 73. The second passage 114 has an annular groove shape in a plan view, and a part thereof is formed as an oil reservoir 114a having an increased width and depth so that a predetermined amount of lubricating oil can be stored.
[0038]
Further, below the discharge port 74, a concave portion 120 is provided on the upper surface of the transfer case 21, and an oil passage 121 communicating with the internal space of the case 20 is provided on the bottom surface thereof.
[0039]
Next, distribution of the lubricating oil will be described. As described above, the oil pump 80 always operates when the transfer input shaft 22 is rotating, that is, when the vehicle is running. Here, in the transfer case 20, a required amount of lubricating oil determined by the volume in the transfer case 21 and the number and size of the gears accommodated in the case 21 is stored. In the state, the upper surface of the lubricating oil is located at the position indicated by reference numeral S1.
[0040]
When the oil pump 80 operates, the lubricating oil in the oil pan 90 flows into the oil pump 80 through the first oil passage 100. The inflowing lubricating oil is discharged to the second oil passage 110 by the rotation of the drive rotor 83 and the driven rotor 84 of the oil pump 80, and flows into the oil cooler 70 from the suction port 73 through the second oil passage 110. Then, after being cooled through the space between the fins, the air is discharged from the discharge port 74 to the concave portion 120, and is supplied to the bearings 29 and 30 of the transfer output shaft 25 through the oil passage 121. The supplied lubricating oil cools and lubricates the bearings 29 and 30 and the transfer output shaft 25, and after lubricating and cooling each member in the case 21, returns to the oil pan 90. Further, in the oil pump operating state, the lubricating oil is circulating in each part in the transfer case 21, so that the upper surface of the lubricating oil is lowered to the position indicated by reference numeral S2.
[0041]
As described above, according to the present embodiment, the oil cooler 70 is provided immediately above the bearings 29 and 30 of the transfer output shaft 25 that are easily heated. As a result, the lubricating oil cooled by the oil cooler 70 can be supplied to the bearings 29, 30 of the transfer output shaft 25 while being substantially cooled, and the bearings 29, 30 And its vicinity can be effectively cooled by the lubricating oil. In particular, as in the present embodiment, the engine 1 is disposed in front of the vehicle body, and the transfer output shaft 25 is positioned above the steering rack 50 extending in the vehicle width direction on the suspension cross member 51 extending in the vehicle width direction. By being located, a great effect is exhibited when cooling by cooling air cannot be expected very much.
[0042]
In addition, an oil pan 90 capable of storing a predetermined amount of lubricating oil is provided below the drive gear 23 so as to protrude downward from the lower part of the transfer case 21, so that the volume in the case, the number and size of the gears are provided. Of the required amount of lubricating oil determined according to the limit oil temperature and the like, a predetermined amount of lubricating oil will be stored in the oil pan 90, and is provided so as to protrude downward from the lower part of the transfer case 21. The upper surface of the lubricating oil stored in the transfer case 21 is lower than when the oil pan 90 is not provided. That is, the depth at which the gears such as the drive gear 23 housed in the transfer case 21 are immersed in the lubricating oil is reduced, the stirring resistance is reduced, and the temperature rise of the lubricating oil is suppressed. In other words, the lubricating oil further contributes to the improvement of the cooling effect.
[0043]
On the other hand, even when the oil pump 80 is operating, the lubricating oil is circulated and diffused in the transfer case 21, so that the upper surface of the lubricating oil is lowered. Therefore, even when the oil level is low, the lubricating oil can be reliably sucked. In other words, the lubricating oil can be circulated in the transfer case 21 if the lubricating oil remains in the oil pan 90 even if the amount is small, so that the required amount of lubricating oil is reduced from the volume in the transfer case 21. As a result, as described above, the depth at which the drive gear 23 is immersed in the lubricating oil is reduced, the stirring resistance is reduced, and the temperature rise of the lubricating oil is suppressed.
[0044]
In addition, since the oil reservoir 114a is provided near the oil cooler 70, the lubricating oil is stored even in the middle of the lubrication path, and the effect of lowering the upper surface of the lubricating oil surface is obtained as in the oil pan 90. Further, the upper surface of the lubricating oil can be further reduced by the oil reservoir 114a, and the stirring effect of the lubricating oil can be further reduced to improve the cooling effect.
[0045]
In the case where the surrounding thermal environment is severe as described above, the lubricating oil cannot be sufficiently cooled if the oil cooler is an air-cooled type. However, in the present embodiment, the oil cooler 70 is Therefore, the lubricating oil can be effectively cooled even when the surrounding thermal environment is severe.
[0046]
In the present embodiment, since oil pump 80 is driven by rotation of idle shaft 24, members such as a gear train for transmitting power to oil pump 80 and shafts for supporting the gear train are provided. Need not be newly provided.
[0047]
Further, since the rotation of the transfer input shaft 22 is transmitted to the idle shaft 24 at an increased speed, the rotation of the oil pump 80 is increased and the pump capacity is improved. That is, the required discharge amount can be secured without increasing the size of the oil pump 80, and the bearings 29, 30 and the like of the transfer output shaft 25 can be satisfactorily lubricated. In addition, a sufficient amount of lubricating oil can be supplied to the oil cooler 70, and the lubricating oil can be cooled effectively.
[0048]
When power is being input to the transfer input shaft 22, the idle shaft 24 is constantly driven by the rotation of the transfer input shaft 22, and the oil pump 80 is constantly operated. Further, as described above, since the rotation of the transfer input shaft 22 is transmitted to the idle shaft 24 at an increased speed, the oil pump 80 operates effectively when the rotation of the transfer input shaft 22 is low. .
[0049]
In addition, since the rotation shaft 81 that transmits the rotation of the idle shaft 24 to the oil pump 80 is made thinner than the transfer input shaft 22, the oil pump 80 can be used more easily than when the transfer input shaft 22 is directly connected to the oil pump 80. The size can be reduced.
[0050]
In addition, an oil passage for supplying lubricating oil from the oil pump 80 to the oil cooler 70 is formed by using first and second pipe members 111 and 112, and these pipe members 111 and 112 are provided in a space in the transfer case 21. Since it is arranged, it does not interfere with the devices arranged around the engine accessory and the like, for example, as compared with the case where it is provided outside the case 21, and the degree of freedom of the layout of the peripheral devices increases. Further, when the peripheral devices become high in temperature, the peripheral devices are less susceptible to heat from them.
[0051]
In the above embodiment, the rotation of the transfer input shaft 22 is transmitted at an increased speed to the idle shaft 24 by the drive gear 23 and the driven gear 26, but the idle shaft is orthogonal to the transfer input shaft 22. A bevel gear set for transmitting the rotation of the transfer input shaft to the idle shaft at an increased speed may be provided therebetween, and an oil pump may be provided at one end of the idle shaft.
[0052]
Further, instead of the rotary shaft 81, the tip of the idle shaft 24 may be thinned and directly fitted into the oil pump 80.
[0053]
【The invention's effect】
As described above, according to the present invention, since the oil pump is driven by the rotation of the power transmission shaft, members such as a gear train for transmitting power to the oil pump and shafts for supporting the gear train are provided. Need not be newly provided.
[0054]
In addition, since the rotation of the input shaft is transmitted to the power transmission shaft at an increased speed, the rotation of the oil pump is increased and the pump capacity is improved. That is, a sufficient discharge amount can be secured without increasing the size of the oil pump. For example, if the lubricating oil is supplied to an oil cooler for cooling the lubricating oil by the oil pump, the lubricating oil can be effectively cooled.
[Brief description of the drawings]
FIG. 1 is a skeleton diagram of a mechanical configuration (power transmission path) of a four-wheel drive device according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of a periphery of a front differential and a transfer of the four-wheel drive device.
FIG. 3 is a layout diagram of the four-wheel drive device at a front part of a vehicle body.
FIG. 4 is a perspective view of the periphery of the four-wheel drive device.
FIG. 5 is a partially broken side view of the four-wheel drive device.
FIG. 6 is a sectional view of an oil pump provided in the four-wheel drive device.
FIG. 7 is a view taken along line CC of FIG. 6;
[Explanation of symbols]
1 engine
20 Transfer case (case)
22 Transfer input shaft (input shaft)
23 Drive gear (input gear, speed increasing means)
24 Idle shaft (power transmission shaft)
25 Transfer output shaft (output shaft)
26 driven gear (transmission gear, speed increasing means)
29, 30 Bearing part
50 Steering rack (steering member)
51 suspension cross member
70 Oil cooler
80 oil pump
81 Rotary shaft (small diameter shaft)
90 oil pan (oil reservoir provided below input gear and capable of storing a predetermined amount of lubricating oil)
100 1st oilway
110 second oil passage (oil passage for supplying lubricating oil from oil pump to oil cooler)
111 1st pipe, 2nd pipe

Claims (5)

An input shaft arranged in the vehicle width direction to receive power from a front engine, an output shaft orthogonal to the input shaft and extending rearward of the vehicle body, and a power transmission shaft for transmitting power from the input shaft to the output shaft And a case for accommodating the power transmission shaft, and the output shaft is disposed above a steering member extending in the vehicle width direction on a suspension cross member disposed in the vehicle width direction, and An oil pump for supplying lubricating oil to a predetermined portion in a case is a drive device of a four-wheel drive vehicle provided in the case, and power transmission of rotation of the input shaft between the input shaft and a power transmission shaft. A speed increasing means for increasing the speed of the power transmission to the shaft is provided, and the oil pump is provided on the axis of the power transmission shaft, and is configured to be driven by rotation of the transmission shaft. Features of four-wheel drive vehicles Operated device. The input shaft and the power transmission shaft are disposed in parallel, and the speed increasing means includes an input gear provided on the input shaft, and a transmission gear provided on the power transmission shaft and meshed with the input gear. The drive device for a four-wheel drive vehicle according to claim 1, wherein: 3. The four-wheel drive vehicle drive device according to claim 1, wherein the oil pump is configured to be driven by a small-diameter shaft portion provided at one end of the power transmission shaft. An oil reservoir capable of storing a predetermined amount of lubricating oil is provided below the input gear provided on the input shaft so as to protrude downward from the lower portion of the case, and the oil pump sucks lubricating oil from the oil reservoir. The drive device for a four-wheel drive vehicle according to any one of claims 1 to 3, wherein: An oil cooler for cooling the lubricating oil is provided, and an oil passage for supplying the lubricating oil from the oil pump to the oil cooler is configured using a pipe, and the pipe is disposed in a space in the case. The drive device for a four-wheel drive vehicle according to any one of claims 1 to 4, wherein:

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