JPH04118820U - 4 wheel drive vehicle - Google Patents

Abstract

(57) [Summary] [Purpose] It is possible to change the power transmission mode during normal driving and when starting, thereby improving starting performance on steep uphill slopes, etc. [Structure] The center differential 10 is provided with a direct coupling dog clutch 30 that integrates it, and the drive system that transmits power from the center differential 10 to the rear wheels 26 includes a viscous coupling 31 and a locking dog clutch that locks it. 32 is provided, and a double dog clutch 3
At 0 and 32, there is an operating lever 34 for changing the power transmission mode.
When driving normally, the vehicle can be set to full-time power transmission mode, resulting in 4-wheel drive driving, and when starting up a steep hill, etc., switching to part-time power transmission mode can result in 2-wheel drive driving. This makes it possible to start the vehicle without stalling even if the clutch is operated incorrectly.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention relates to full-time four-wheel drive vehicles equipped with a center differential. For details, see the method for changing the power transmission mode between starting and normal driving. It is.

0002

[Conventional technology]

Conventionally, four-wheel drive vehicles equipped with a center differential have been As shown in the prior art of Publication No. 64-63536, the output side of the transmission is centered. Input to the differential to distribute the power equally to the two output shafts, each output shaft Transmission is configured for the front and rear wheels, and the center differential is equipped with a viscous squash. Provide a pulling differential limiting mechanism. And, power is always transmitted to the front and rear wheels and a single Drives in 4-wheel drive in power transmission mode, and the difference in rotation during turns is determined by the center differential If one of the front or rear wheels spins, the differential limiting mechanism will reduce the center differential. It is configured to lock the differential.

0003

[Problem that the idea aims to solve]

By the way, in the prior art mentioned above, a single power source driving all four wheels simultaneously It is configured in transmission mode and there is no problem during normal driving, but the following malfunctions may occur. cause a collision. In other words, when starting on a steep uphill slope, all four wheels are driven at the same time. In addition, the wheels become less likely to spin, and high clutch torque is required. Therefore, sufficient Slip the clutch while keeping the clutch in a half-clutch state when the engine is generating a certain amount of torque. It is necessary to connect the clutch smoothly, and if the clutch is operated in a short period of time, the engine may easily stall. There is a problem. Here, when starting, the front wheels are mainly driven to make it easier for the front wheels to initially spin, If the rear wheels are then driven, the clutch can be suddenly engaged when starting up a steep hill. It will be possible to start even if you do. Therefore, considering the starting performance, the center differential Even if it is a four-wheel drive vehicle equipped with a dual-wheel drive system, the drive torque distribution to the front and rear wheels can be varied. It is required to enable switching of power transmission modes.

0004 The present invention was developed in view of this point, and the power transmission is controlled during normal driving and when starting. By making it possible to change the mode, it is possible to improve starting performance on steep uphill slopes, etc. purpose.

[0005]

[Means to solve the problem]

In order to achieve the above object, the present invention is equipped with a differential limiting mechanism on the output side of the transmission. Power is transmitted to the front and rear wheels through a center differential.4 In wheel drive vehicles, a direct coupling mesh that integrates it into the center differential. A drive system with a clutch that transmits power from the center differential to the rear wheels. A viscous coupling and a locking clutch are installed to lock the viscous coupling. The double-mesh clutch has a full-time center differential and a visca An operating system is also provided to change to full-time power transmission mode with coupling operation. It is.

[0006]

[Effect]

Based on the above configuration, a center differential direct connection and a viscous coupling are installed. During normal driving, operate the dog clutch for locking the sensor to the specified position. By switching to the tar differential full-time power transmission mode, the original four-wheel When driving on a steep uphill slope, a viscous coupling is applied to the rear wheel power transmission system. Clutch operation is reduced by using full-time viscous power transmission mode via clutch. Even if there is a defect in the construction, it will be possible to start without stalling.

[0007]

【Example】

Hereinafter, embodiments of the present invention will be described based on the drawings. In Figure 1, the center To explain the drive system of a four-wheel drive vehicle equipped with a differential, code 1 is the engine. This engine 1 is connected to a transmission 4 via a clutch 2 and an input shaft 3. be done. The transmission 4 has a multi-stage change gear 6 on the input shaft 3 and the output shaft 5 in a synchronizing mechanism 7. The output shaft 5 is configured to obtain a plurality of forward speeds and reverse speeds by selecting from It is connected to the center differential 10 of the transfer device 8. center de The differential 10 has a differential case 10a connected to the output shaft 5. A pair of side gears 10c and 10d mesh with the pinion gear 10b of the case 10a. It is composed of One of the side gears 10c is a screw as a differential limiting mechanism. Connected to the front drive shaft 12 via the housing 11a of the cass coupling 11. This front drive shaft 12 connects to the final gears 13a, 13b, and the front drive shaft 12. Power is transmitted to the front wheels 16 via a differential 14 and an axle 15.

[0008] In addition, the other side gear 10d of the center differential 10 has a trans The transfer shaft 20 is connected to the viscous coupling 11. It is directly connected to the hub 11b inside the housing 11a. Viscous coupling 1 1, the inner plate 11c on the housing side and the outer plate 11d on the hub side intersect. The housing is arranged in a sealed manner with silicone oil sealed inside. A viscous torque is generated according to the rotational difference between the ring 11a and the hub 11b, resulting in a differential limiting operation. use The transfer shaft 20 is further connected to the rear via a pair of gears 21a, 21b. This rear drive shaft 22 connects to a propeller shaft 23 and a rear drive shaft 22. Power is transmitted to the rear wheels 26 via a differential 24 and an axle 25.

[0009] In the above drive system, the center differential is used to change the power transmission mode. A direct coupling meshing clamp is provided between the differential case 10a of the shaft 10 and the transfer shaft 20. A switch 30 is provided. Moreover, the above-mentioned structure is provided between the rear drive shaft 22 and the propeller shaft. A similar viscous coupling 31 and locking dog clutch 32 are provided. Ru. Furthermore, as a manual operation system for these dog clutches, double dog clutches are also available. The actuators 30a and 32a on the sleeve side of 30 and 32 are connected to the cable 33, etc. and is connected to the operating lever 34.

0010 Next, the operation of this embodiment will be explained. First, during normal driving, the control lever 34, operate the direct coupling dog clutch 30 to the free position as shown in Fig. The tar differential 10 is made differentially movable, and the locking dog clutch 32 is locked. The viscous coupling 31 is locked by operating it to the locked position. center differential full-time power transmission mode. Therefore, The power of the engine 1 is input to the transmission 4 via the clutch 2 and the input shaft 3, and the transmission power is is transmitted to the differential case 10a of the center differential 10, the sensor Since the tar differential 10 is differentially variable, the pair of side gears 10c, 1 The power is distributed equally to 0d. Then, from one side gear 10c, viscous The front wheel 1 is connected to the front wheel 1 through the housing 11a of the coupling 11, the front drive shaft 12, etc. At the same time, the power is transmitted to the transfer shaft 20, one from the other side gear 10d. Pair of gears 21a, 21b, rear drive shaft 22, viscous coupling in locked state The power is transmitted to the rear wheels 26 through the rings 31, etc., and in this way four-wheel drive driving is possible. do.

[0011] When steering in this driving condition, the front and rear differentials 14 and 24 Similarly, for the differential operation of the center differential 10, the front and rear wheels 16 and 26 are rotated. Absorbs rolling differences and turns smoothly. Also, at this time, with viscous coupling 11 is an inner plate 11c on the front wheel 16 side and an outer plate 11d on the rear wheel 26 side. is rotating in oil, and one of the front and rear wheels 16 and 26 may spin on rough roads. If a large rotational difference occurs, the viscous torque corresponding to the rotational difference will cause the center To limit the differential movement of the differential 10. And depending on this viscous torque The power is transmitted to the side that does not idle, making it easier to escape from rough roads. Become.

0012 On the other hand, when starting on a steep uphill slope, etc., use the operating lever 34 to Operate the direct coupling dog clutch 30 to the direct coupling position and set the center differential 1. 0 is integrated so that it cannot be differentially moved, and the locking dog clutch 32 is operated to the free position. The viscous coupling 31 is made operational. Then, in this case, the transmission 4 The output side is directly connected to the front wheels 16 via the integrated center differential 10, etc. and a viscous type full wheel connected to the rear wheel 26 via a viscous coupling 31. It becomes time power transmission mode. Therefore, if the front wheels 16 do not spin on dry roads etc. In this case, most of the shifting power is transmitted to the front wheels 16 to start the vehicle. steep uphill Under the driving conditions of this viscous type power transmission mode, the front wheels tend to spin when the vehicle is started. Therefore, even if the clutch 3 is suddenly engaged, the front wheels 16 will spin rather than the engine stopping. This makes it possible to start the vehicle without stalling the engine. this front wheel Following the idling of 16, the viscous coupling 31 operates, and due to its responsiveness, the rear wheel Since power is smoothly transmitted to 26, starting is ensured.

[0013] Furthermore, at this time, the viscous coupling 31 is connected to the rear drive shaft on the front wheel 16 side. 22 and the propeller shaft 23 on the rear wheel 26 side has been detected, and the front wheel 16 is idling. When a large rotational difference occurs, power is transmitted to the rear wheels 26 by viscous torque, Four-wheel drive will ensure reliable start-up. After starting, use the operating lever 34 to By operating the dog clutches 30 and 32 to the normal running position, the original full-tire The system returns to power transmission mode. In addition, such a change in power transmission mode By doing this not only at high speed but also at reverse speed, you can drive in the same way.

[0014] In FIG. 3, another embodiment of the present invention is shown in which the dog clutch is automatically switched. To explain the case where the vehicle speed sensor 40 and tilt sensor 41 input signals The control unit 42 has a control unit 42. The control unit 42 receives signals from both sensors 40 and 41. to determine whether to start on a steep uphill slope or to drive other than that, and when starting on a steep uphill slope, the electric A signal is output to actuators 30a and 32a of both dog clutches 30 and 32. to a viscous full-time power transmission mode position. As a result, when starting on a steep uphill slope, both dog clutches 30 and 32 are automatically activated. It is switched to full-time viscous power transmission mode.

[0015] Although the embodiments of the present invention have been described above, the present invention is not limited thereto. for example , a viscous coupling and its locking clutch are attached to the center differential. It is located closer to the front wheel than the front wheel, and is the main driver in the viscous type full-time power transmission mode. It may be configured such that the driving force is used to drive the rear wheels.

[0016]

[Effect of the idea]

As explained above, according to the present invention, a four-wheel drive system equipped with a center differential Center differential full-time power transmission mode in wheel drive vehicles In addition, it can be changed to viscous type full-time power transmission mode, This improves the starting performance when starting up steep hills, etc., and makes clutch operation easier. Viscous In full-time power transmission mode, 4-wheel drive is possible using a viscous coupling. Since it is possible to do this, running performance at the time of starting is also ensured. Two types of meshing cracks The structure is simple and the operation is easy. is also easy. An automated system provides even better operability.

[Brief explanation of drawings]

FIG. 1 is a skeleton diagram of an embodiment of a four-wheel drive vehicle according to the present invention.

FIG. 2 is a skeleton diagram of main parts showing the operation state when starting on a steep uphill slope.

FIG. 3 is a configuration diagram of another embodiment of the operating system of the present invention.

[Explanation of symbols]

4 Transmission 10 Center differential 11 Viscous coupling for differential limiting 16 Front wheel 26 rear wheel 30 Direct connection dog clutch 31 Viscous coupling 32 Lock dog clutch 34 Operation lever

Claims (4)

[Scope of utility model registration request] Claim 1: In a four-wheel drive vehicle in which the output side of a transmission is configured to transmit transmission to front wheels and rear wheels respectively via a center differential equipped with a differential limiting mechanism, a direct coupling mesh that integrates the output side with the center differential. The drive system that transmits power from the center differential to the rear wheels is equipped with a viscous coupling and a locking dog clutch that locks it. A four-wheel drive vehicle characterized by being provided with an operation system for changing to a ring-operated full-time power transmission mode. [Claim 2] The operation system sets the direct coupling dog clutch to the free position and the locking dog clutch to the lock position to enter the full-time power transmission mode during normal driving, and the direct coupling dog clutch to the direct coupling position. 2. The four-wheel drive vehicle according to claim 1, wherein the four-wheel drive vehicle is configured to switch to a full-time power transmission mode when starting on a slope by setting the locking dog clutch to a free position. 3. The operating system according to claim 1, wherein the operating system is configured to change the power transmission mode by manual operation or automatically according to driving conditions.
wheel drive car. 4. The four-wheel drive vehicle according to claim 1, wherein the direct-coupling dog clutch, the viscous coupling, and the locking dog clutch are arranged in series with the transfer device.