JPH0717564Y2 - 4-wheel drive transfer device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a four-wheel drive transfer device having a wet multi-plate clutch mechanism.

[Prior Art] A conventional four-wheel drive transfer device is, for example, a third one.
There is something like the one shown in the figure.

In FIG. 3, 51 and 52 are casings and 53 is a casing 5.
A main shaft rotatably supported by 1,52, 54 is a planetary gear mechanism, and 55 is a switching mechanism for switching the planetary gear mechanism 54 to low or high. Further, 56 is a wet multi-plate clutch mechanism capable of absorbing differential rotation, 57 is a drive sprocket connected to the wet multi-plate clutch mechanism 56, 58 is a driven sprocket connected to the drive sprocket 57 via a chain 59, and 60 is It is a front drive shaft integrally formed with a driven sprocket 58.

The rotational force of the main shaft 53 is switched to low or high by the switching mechanism 55 via the planetary gear mechanism 54, is transmitted to the drive sprocket 57 via the wet multi-plate clutch mechanism 56, and is transmitted from the drive sprocket 57 to the chain 59 and driven. It is transmitted to the front drive shaft 60 via the sprocket 58. In this way, the rotational force is transmitted from the front drive shaft 60 to the front wheels, and a four-wheel drive traveling state is set.

Here, this transfer device is
Oil pump 61 and DC motor 62 that drives the oil pump 61
Is provided on the outside of the casing 52, and the piston 63 is operated by the operating pressure from the oil pump 61 to fasten the wet multi-plate clutch mechanism 56.

[Problems to be solved by the invention] However, in such a conventional transfer device, when a DC motor that drives an oil pump is continuously used for a long time, energy of 50 W or more is consumed, and a battery is used in a vehicle. There was a problem that it would go up.

The present invention has been made in view of the above conventional problems, and provides a transfer device capable of preventing the battery of a vehicle from rising by driving a DC motor only when the vehicle is stopped. Has an aim.

[Problems to be Solved by the Invention] In order to achieve the above object, according to the present invention, the rotational force of a main chassis rotatably supported by a casing is fastened by supplying an operating pressure to a piston liquid chamber. In a four-wheel drive transfer device that transmits from a sprocket to a front drive shaft via a wet multi-plate clutch mechanism,
A first oil pump that obtains a piston working pressure by driving the main shaft when the vehicle is running, and a second oil pump that obtains a piston working pressure by driving a DC motor when the vehicle is stopped are provided, and when the second oil pump is stopped. A one-way valve for preventing backflow of the operating pressure from the first oil pump is provided in a communication passage communicating with the piston liquid chamber.

[Operation] In the present invention, when the vehicle is running, the main shaft is driven to operate the first oil pump to secure the piston working pressure, and when the vehicle is stopped, the second oil pump is driven by the DC motor to operate the piston. Secure pressure.

Further, a one-way valve is provided in a passage communicating with the piston liquid chamber so that the operating pressure from the first oil pump does not flow backward when the second oil pump is stopped.

Therefore, since it is not necessary to continuously drive the DC motor, the battery of the vehicle can be prevented from running out.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

1 and 2 are views showing an embodiment of the present invention.

First, the structure will be described. In FIG.
Is a casing, and the main shaft 3 is rotatably supported by these casings 1 and 2 via bearings 4 and 5. An oil passage 6 is formed inside the main shaft 3 to lubricate each lubrication site.

Reference numeral 7 is a planetary gear mechanism. The planetary gear mechanism 7 is composed of a sun gear 8, a ring gear 9, a carrier 10 rotating on the same axis as these, and a planetary gear 11 supported by the carrier 10. There is. A switching mechanism 12 switches the planetary gear mechanism 7 to low (L) or high (H). The switching mechanism 12 is a hub 13 rotatably supported by the carrier 10.
And a dock gear 14 splined to the carrier 10
And a clutch gear 16 fixed to the casing 15, a coupling sleeve 17 meshing with the clutch gear 16, and a fork 18 for moving the coupling sleeve 17.

Reference numeral 19 denotes a wet multi-plate clutch mechanism for performing 2-4 drive switching and variable torque control.
19 is a drum splined to the main shaft 3.
20 and a plate splined to the inner circumference of the drum 20
21, a hub 23 splined to the drive sprocket 22, and a plate 24 splined to the hub 23,
It is composed of a piston 25 that presses these plates 21 and 24.

A chain 27 is installed between the drive sprocket 22 and the driven sprocket 26.
Is integrally formed with the front drive shaft 28.
The front drive shaft 28 is rotatably supported by the casings 1 and 2 via bearings 29 and 30.

Reference numeral 31 denotes a pump housing, and a first oil pump 34 including an inner gear 32 and an outer gear 33 is provided inside the pump housing 31, and the first oil pump 34 is driven by the main shaft 3.

In addition, an introduction passage 36 for introducing oil for driving the piston 25 is provided in the cover 35 in contact with the pump housing 31.
A and 36B are formed, and the introduction passages 36A and 36B communicate with the piston liquid chamber 37.

The first oil pump 34 communicates with the introduction passage 36B, supplies the piston working pressure to the piston liquid chamber 37, and supplies the lubricating oil to the oil passage 6.

On the other hand, at the bottom of the casing 2, the second oil pump 39
A DC motor 40 for driving the second oil pump 39 is attached via the boss portion 38.

Reference numeral 41 is a rotating shaft of the DC motor 40, and 42 is an oil seal attached to the rotating shaft 41. 43 is the second oil pump 39
Of the pump housing, 44 is a pump gear, 45 is an O-ring mounted between the pump housing 43 and the boss portion 38, 46 is a drain hole, and 47 is a discharge port.

Here, as shown in FIG. 1, a communication passage 48 is provided between the second oil pump 39 and the introduction passage 36B that communicates the first oil pump 34 with the pump liquid chamber 37. Passage 48
A one-way valve 49 is installed in the middle of. Second
The one-way valve 49 prevents the reverse flow of the oil from the first oil pump 34 when the second oil pump 39 is stopped.

Next, the operation will be described.

When the vehicle is running, the first shaft 3 is driven to drive the first
The oil pump 34 operates and the piston working pressure is introduced.
36B Piston fluid chamber 37 via 2WD-4WD switching valve 70
To operate the piston 25 with this operating pressure.

On the other hand, when the vehicle is stopped (pressure is reduced), the second oil pump 39 is driven by the DC motor 40 so that the piston working pressure is controlled by the one-way valve 49 in the communication passage 48 and the 2WD-4WD switching valve 70.
Is supplied to the piston liquid chamber 37 via the, and the piston 25 is operated.

When the second oil pump 39 is stopped, the one-way valve 49 blocks the reverse flow of the operating pressure from the first oil pump 34.

In addition, the switching of 2WD-4WD is performed by the solenoid 71.
Drive the 4WD drive switching valve 70.

In this way, the DC motor 40 is driven only when the vehicle is stopped, so it is possible to prevent the vehicle battery from rising.

[Advantage of the Invention] As described above, according to the present invention, the DC motor drives the second oil pump to secure the piston working pressure only when the vehicle is stopped. Therefore, the DC motor is continuously operated. It is possible to prevent the battery of the vehicle from being exhausted.

[Brief description of drawings]

FIG. 1 is a sectional view showing an essential part of an embodiment of the present invention, FIG. 2 is an overall sectional view, and FIG. 3 is a sectional view showing a conventional example. In the figure, 1,2,15 ... Casing, 3 ... Main shaft,
4,5,29,30 …… Bearing, 6 …… Oil passage, 7 ……
Planetary gear mechanism, 8 ... Sun gear, 9 ... Ring gear, 10
...... Carrier, 11 …… Planetary gear, 12 …… Switching mechanism, 13 …… Hub, 14 …… Dock gear, 16 …… Clutch gear, 17 …… Coupling sleeve, 18 …… Fork, 19
...... Wet multi-plate clutch mechanism, 20 ...... Drum, 21,24 ......
Plate, 22 …… Drive sprocket, 23 …… Hub,
25 …… Piston, 26 …… Driven sprocket, 27 ……
Chain, 28 ... Front drive shaft, 31 ... Pump housing, 32 ... Inner gear, 33 ... Outer gear, 34 ... First oil pump, 35 ... Cover, 36A, 36
B …… Introduction passage, 37: Piston fluid chamber, 38 …… Boss part, 39…
… Second oil pump, 40 …… DC motor, 41 …… Rotating shaft,
42 …… Oil seal, 43 …… Pump housing, 44 ……
Pump gear, 45 ... O-ring, 46 ... Drain hole, 47 ...
… Discharge port, 48 …… Communication passage, 49 …… One-way valve, 70
...... 2WD-4WD switching valve, 71 …… 2WD-4WD switching solenoid.

Claims (1)

[Scope of utility model registration request] 1. A four-wheel system in which the rotational force of a main shaft rotatably supported by a casing is transmitted from a sprocket to a front drive shaft via a wet multi-plate clutch mechanism that is fastened by supplying an operating pressure to a piston liquid chamber. The drive transfer device is provided with a first oil pump that obtains a piston working pressure by driving the main shaft when the vehicle is running, and a second oil pump that obtains a piston working pressure by driving a DC motor when the vehicle is stopped. A four-wheel drive transfer device, wherein a one-way valve for preventing backflow of the operating pressure from the first oil pump is provided in a communication passage communicating with the piston liquid chamber when the oil pump is stopped.