JPH0735156U - Rear biaxial vehicle drive - Google Patents

Abstract

(57) [Summary] (Modified) [Purpose] Regarding a drive device for a rear two-axle vehicle that improves startability when the vehicle is empty, the mechanism is simple, lightweight, and low cost, and the loadable amount is safely increased. Therefore, a drive device for a rear two-axle vehicle that can start on a low friction road when the vehicle is empty even if the load distribution on the rear front axle is reduced is provided. In a drive device of a rear two-axle vehicle having a drive mechanism for the rear two shafts and an interrupting mechanism for the drive force to the rear-front shaft, a sub-propeller shaft 20 in which a divider gear 12 for driving the rear front shaft is extended, A drive pinion 21 attached to the sub-propeller shaft, a gear 30 that meshes with the drive pinion and is connected to the shaft of one of the rear wheels, and a clutch device 17 provided in the middle of the sub-propeller shaft, Have.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a drive device for a rear two-axle vehicle that improves startability when the vehicle is empty.

[0002]

[Prior art]

 In order to safely increase the load weight of the vehicle, a rear two-axle vehicle has been developed in which the rear axle of the vehicle is composed of two axles and the load on the wheels is divided. This rear two-axle vehicle is classified into a rear two-axis drive vehicle and a rear front-axis drive vehicle due to the difference in the rear axle drive device.

The former rear two-axle drive vehicle transmits a driving force to both the rear front shaft and the rear-front shaft. Therefore, the ground contact area of the drive wheels is large, and the startability when the vehicle is empty is improved. Also, the latter rear-front axle drive vehicle is known as a compact, lightweight, low-cost rear two-axle vehicle. The rear-front axle drive vehicle transmits the driving force only to the rear-front axle. The mechanism is similar to that of a normal rear single-axle vehicle, in which the driving force from the engine is transmitted to the differential unit of the rear and front shafts via a clutch, transmission, propeller shaft, etc., and the rear shaft is allowed to rotate freely. The mechanism has the advantage that it is simple.

Further, the "driving force transmission device for rear two-axle vehicle" described in Japanese Utility Model Laid-Open No. 63-51830 has been filed by the same applicant for utility model registration as the present invention. FIG. 4 is a schematic side view showing the conventional rear axle drive device.

In the configuration shown in FIG. 4, the propeller shaft 10 and the divider gear 12 are joined on the same shaft, and the divider gear 12 meshes with a spur gear 14 via an idle gear 13. The spur gear 14 and the drive pinion 15 are coaxially joined to each other, the drive pinion 15 and the ring gear 16 mesh with each other, and the ring gear 16 drives a differential device (not shown) for the rear front wheels. The sliding clutch 17 is arranged coaxially with the divider gear 12, the output shaft 19 is inserted into the shaft of the sliding clutch 17, and the axial groove formed on the inner surface of the sliding clutch 17 and the axial direction formed on the surface of the output shaft. The groove is engaged and the sliding clutch 17 is expanded and contracted by the cylinder 18 to connect and disconnect the divider gear 12 and the sliding clutch 17. The output shaft 19 and the sub-propeller shaft 20 are joined on the shaft, the sub-propeller shaft 20 and the drive pinion 21 are joined on the shaft, the drive pinion 21 and the ring gear 22 are meshed with each other, and the ring gear 22 is the rear differential wheel. Drive a device (not shown).

In operation, the drive force from the engine rotates the divider gear 12 via the propeller shaft 10 on the rear front shaft side, and the ring gear 16 via the idle gear 13, the spur gear 14, and the drive pinion 15. Rotates. The rotation of the ring gear 16 drives the differential device of the rear front wheels to rotationally drive the rear front wheels, which becomes the propulsive force of the vehicle.

[0007] During normal running, since the sliding clutch 17 and the divider gear 12 are separated from each other on the rear axle side, the driving force from the engine is not transmitted to the rear axle side and rotates freely, so that the vehicle becomes a rear front axle drive vehicle.

When traveling on a low friction road such as a snowy road, when air pressure is supplied to the cylinder 18 by the driver's manual operation, the iron arm of the cylinder 18 extends the sliding clutch 17, and the sliding clutch 17 and the divider gear 12 are tightened. Accordingly, the rotation of the divider gear 12 is transmitted to the ring gear 22 via the sliding clutch 17, the output shaft 19, the sub propeller shaft 20, and the drive pinion 21. The rotation of the ring gear 22 drives the rear-rear wheel differential device to rotate both rear-rear axle wheels, resulting in a rear two-axis drive vehicle. FIG. 5 is a diagram showing drive wheels when traveling on a low friction road. Reference numeral 10 is a propeller shaft, 20 is a sub-propeller shaft, 40 is a rear-front shaft differential unit, 41 is a rear-rear shaft differential unit, 42 and 43 are rear front wheels, and 44 and 45 are rear-rear wheels. The rear front wheels 42 and 43 and the rear rear wheels 44 and 45, which are hatched in the figure, are the drive wheels when traveling on a low friction road.

As described above, by driving the front and rear axles during general running, the drive force transmission path on the rear axle side is cut off, and transmission loss of the drive force is eliminated to improve fuel efficiency. When driving on low-friction roads such as snowy roads, the rear two-axis drive vehicle will be used to improve running performance.

[0010]

[Problems to be solved by the device]

 However, the conventional drive devices for rear two-axle vehicles have the following problems, respectively.

Due to its mechanism, a rear two-axle drive vehicle transmits the driving force from the engine to a differential device (hereinafter referred to as a differential) between the rear front shaft and the rear two shafts via a clutch, a transmission, a propeller shaft, and the like. Further, the wheels are driven via the front-rear axle differential device and the rear-rear axle differential device. Therefore, there is a problem that the mechanism is complicated, the weight is heavy, and the cost is high.

Further, the rear-front axle drive vehicle has a small ground contact area of the drive wheels due to the single-axis drive, and in order to start the wheels without idling on a low friction road such as a snowy road, the rear front-wheel wheels on the drive side are required. It is necessary to apply a sufficient load, and it is necessary to distribute the load so that a large load is applied to the rear and front axles even when the vehicle is empty. Therefore, there is little load margin on the front and rear axles when loading luggage, and the amount that can be loaded is small compared to the rear axle. Therefore, it has been requested to move the load distribution of the rear front axle to the rear axle in order to safely increase the loadable capacity of the rear front axle drive vehicle.However, when the vehicle is empty, the load on the rear front axle is insufficient. There was a problem that when starting on a low friction road, it slipped and it became impossible to start.

Further, in the prior art described in Japanese Utility Model Laid-Open No. 63-51830, the two wheels of the shaft are driven afterward when the vehicle is traveling on a low friction road. Therefore, in order to distribute the driving force to both wheels, a differential drive is installed. It is necessary to install. Further, when the transmission of the driving force to the rear-rear shaft is cut off, the differential device on the rear-rear shaft becomes a heavy load when the rear-rear wheel freely rotates, so a free-wheel device that separates the rear-rear wheel and the differential device. (Also called a freehub) was required, and the operation was troublesome for the driver.

In view of the above circumstances, the present invention has a simple mechanism, light weight, and low cost, and even if the load distribution of the rear and front axles is reduced in order to safely increase the loadable capacity, it is possible to reduce the load when the vehicle is empty. An object of the present invention is to provide a drive device for a rear two-axle vehicle that can start on a friction road.

[0015]

[Means for Solving the Problems]

 According to another aspect of the present invention, in a drive device for a rear two-axle vehicle having a drive mechanism for the rear two shafts and an interrupting mechanism for driving force for the rear-to-rear shafts, a sub gear in which a divider gear for driving the rear front shaft is extended. A propeller shaft, a drive pinion attached to the sub-propeller shaft, a gear that meshes with the drive pinion and is connected to the shaft of one of the rear wheels, and a clutch device provided in the middle of the sub-propeller shaft. , Are included.

According to a second aspect of the present invention, in a drive device for a rear two-axle vehicle having a drive mechanism for the rear two shafts and an interrupting mechanism for the drive force to the rear two shafts, a first drive attached to a propeller shaft. A pinion, a ring gear that meshes with the first drive pinion and is connected to a rear-front shaft differential, a transmission gear that substantially faces the first drive pinion and meshes with the ring gear, and is attached to the transmission gear. A sub-propeller shaft extending rearward to the shaft side, a second drive pinion attached to the sub-propeller shaft, and a gear meshed with the second drive pinion and connected to one of the rear and rear shafts of the wheel. And a clutch device provided in the middle of the sub-propeller shaft.

[0017]

[Action]

 The operation of the device according to claim 1 will be described below. When the clutch device is connected, either the rear axle or the rear axle is driven through the divider gear, the sub-propeller shaft, the drive pinion, and the gear, resulting in three-wheel drive of the rear axle and the rear axle. Therefore, strong starting performance is obtained.

Further, when the clutch device is disengaged, the drive force transmission to the rear rear shaft side is cut off, and the two-wheel drive is performed only for the rear front axle both wheels. The operation of the device according to claim 2 will be described below. The rear and front shafts are driven via a propeller shaft, a drive pinion 1, a ring gear, and a differential device.

When the clutch device is connected to the rear-rear-shaft side, either one of the rear-rear-shaft wheels is driven through the ring gear, the transmission gear, the sub-propeller shaft, the drive pinion, and the gear to drive both rear-rear shaft wheels and Later, it will be driven by one wheel with three wheels, and strong starting performance will be obtained.

Further, when the clutch device is disengaged, the drive force transmission to the rear-side shaft side is cut off, and the two-wheel drive is performed only for the rear front shaft both wheels.

[0021]

【Example】

 An embodiment of the device according to claim 1 will be described in detail. FIG. 1 is a schematic side view showing a rear shaft drive device of this embodiment.

Regarding the structural difference between the present embodiment and the prior art (shown in FIG. 4) described in Japanese Utility Model Laid-Open No. 63-51830, the present embodiment does not include a differential device for the post-axis. Firstly, the drive pinion 21 meshes with the gear 30, and the gear 30 is connected to the shaft of one of the wheels afterward. After that, the other wheel of the shaft is free to rotate without a drive force transmission mechanism. Instead of the cylinder 18, an electrically driven solenoid valve 31 is provided.

The correspondence between the invention according to claim 1 and the present embodiment is as follows. The drive mechanism for the front and rear shafts of the rear two shafts includes a propeller shaft 10, a divider gear 12, an idle gear 13, and a spur gear 14. It corresponds to the drive pinion 15, the ring gear 16 and the rear differential gear, the sub propeller shaft corresponds to the sub propeller shaft 20, the drive pinion corresponds to the drive pinion 21, the gear corresponds to the gear 30, and the clutch. The device corresponds to a sliding clutch 17, an output shaft 19 and a solenoid valve 31.

The operation of the present embodiment will be described. When the vehicle starts, the solenoid valve 31 is driven in the ON direction in the figure by a switch operation manually performed by the driver, and the sliding clutch 17 is tightly engaged with the divider gear 12 to drive the driving force. Is transmitted, and the drive pinion 21 is rotationally driven via the output shaft 19 and the sub-propeller shaft 20. The drive pinion 21 drives the gear 30 to rotate, and the gear 30 then drives either one of the wheels of the rear shaft. Therefore, at the time of starting, three wheels are driven by both wheels of the front and rear axles and one wheel of the rear and rear axles, the contact area of the drive wheels is increased, and stable startability is obtained even on a low friction road. Since the above-mentioned three-wheel drive is only at the time of starting, the deterioration of the driving performance such as the tail swing is within the allowable limit.

FIG. 2 is a diagram showing the drive wheels at the time of starting in this embodiment. Reference numeral 10 is a propeller shaft, 20 is a sub-propeller shaft, 40 is a differential unit for the front and rear shafts, 46 is a gear set for the rear-rear shaft, 42 and 43 are rear front wheels, and 44 and 45 are rear rear wheels. The rear front wheels 42, 43 and the rear-rear axle one wheel 44 shown in the figure are the drive wheels at the time of starting.

In FIG. 1, if the above switch operation is cut off immediately after starting, for example, the iron arm of the solenoid valve 31 moves in the OFF direction in the figure by the biasing force in the solenoid valve 31, and the driving force is transmitted to the shaft afterward. After cutting off, only the front and rear axles are driven. Therefore, the two wheels are driven by the front and rear axles while traveling.

Next, an embodiment of the invention according to claim 2 will be described in detail. FIG. 3 is a schematic side view showing the rear shaft drive device of this embodiment. The structure of the present embodiment is shown. A drive pinion 32 is coaxially joined to the propeller shaft 10, a ring gear 16 is meshed with the drive pinion 32, and the ring gear 16 is driven by a differential device (not shown) on the rear front shaft. Transmit power. A transmission gear 33 is axially supported approximately opposite to the drive pinion 32, meshes with the ring gear 16, a sliding clutch 34 is disposed coaxially with the transmission gear 33, and an output shaft 35 is inserted into the shaft of the sliding clutch 34. The axial groove formed on the inner surface of the sliding clutch 34 and the axial groove formed on the surface of the output shaft 35 are engaged with each other, and the sliding clutch 34 is expanded and contracted by the solenoid valve 36 so that the shaft of the transmission gear 33 and the sliding clutch 34 are connected to each other. Intermittently. The output shaft 35 and the drive pinion 37 are joined on the shaft, the drive pinion 37 meshes with the gear 30, and the gear 30 is connected to either one of the wheels of the rear shaft. After that, the other wheel of the axle rotates freely without a drive force transmission mechanism.

The correspondence between the invention according to claim 2 and this embodiment is as follows: the first drive pinion corresponds to the drive pinion 32, the ring gear corresponds to the ring gear 16, and the transmission gear corresponds to the transmission gear 33. , The sub-propeller shaft corresponds to the output shaft 35, the second drive pinion corresponds to the drive pinion 37, the gear corresponds to the gear 30, the clutch device corresponds to the sliding clutch 34, the output shaft 35, and the solenoid valve 36. .

The operation of the present embodiment will be described. At the time of starting, the solenoid valve 36 is driven in the ON direction in the figure by a switch operation manually performed by the driver, and the sliding clutch 34 is driven in close contact with the transmission gear 33. The force is transmitted and the drive pinion 37 is rotationally driven via the output shaft 35. The drive pinion 37 rotatably drives the gear 30, and the toothed wheel 30 drives one of the wheels of the shaft afterward. Therefore, when starting the vehicle, three wheels are driven by both the front and rear axle wheels and the rear and rear axle one wheel, and stable startability is obtained even on a low friction road. Since the three-wheel drive is only at the time of starting, the deterioration of the driving performance such as the tail swing is within the allowable limit.

Immediately after starting, the switch operation is cut off, and for example, the solenoid valve 34 moves in the OFF direction in the figure by the urging force in the solenoid valve 31, and the driving force transmission to the shaft is cut off afterward, and only the rear front shaft is cut off. Driven. Therefore, two wheels are driven by the front and rear axles while driving.

In each of the above-described embodiments, the vehicle is switched to the three-wheel drive at the time of starting. However, the invention is not limited thereto, and it is of course possible to switch to the three-wheel drive only when strong starting such as low friction road starting is required. Is.

Further, although the three-wheel drive is manually switched in each of the above-described embodiments, the invention is not limited to this. For example, in a known speedometer, the vehicle speed is detected from the number of revolutions of the transmission or the like. However, using a well-known microcomputer, etc., when the change (acceleration) of the vehicle speed at the time of start is more than a predetermined value, it is determined that the drive wheels are idling and a signal is output to the solenoid valve. Of course, it may be automatically switched to three-wheel drive.

[0033]

[Effect of device]

 As described above, according to the invention described in each of the claims, there is no differential device between the third differential and the rear rear wheel, and the structure is different from the conventional two-shaft drive vehicle and the prior art disclosed in Japanese Utility Model Laid-Open No. 63-51830. It is simple, lightweight and low cost.

Further, the load when the rear wheels freely rotate during two-wheel drive is light because there is no rear-shaft differential device, and the free load required in the prior art disclosed in Japanese Utility Model Laid-Open No. 63-51830. The wheel device can now be omitted.

Further, by using the three-wheel drive at the time of starting, the starting performance on the low friction road is improved as compared with the rear-front axle drive vehicle. Furthermore, it has been demanded to increase the loading limit. However, the load distribution, which was closer to the rear-front axle in the conventional rear-front-axle drive vehicle, is applied to the rear axle as much as the above-mentioned startability can be afforded. This makes it possible to increase the load margin of the rear front wheels when loading luggage, making it possible to safely increase the loading limit compared to rear-front axle drive vehicles.

According to the second aspect of the present invention, in addition to the above effects, the divider gear 12, the idle gear 13, and the spur gear 14 are not provided in the structure, so that the structure is simpler, lighter, and lower in weight. The cost.

[Brief description of drawings]

FIG. 1 is a diagram showing a rear shaft drive device according to an embodiment of the present invention.

FIG. 2 is a diagram showing drive wheels at the time of starting of the embodiment according to claim 1;

FIG. 3 is a diagram showing a rear shaft driving device according to an embodiment of the present invention.

FIG. 4 is a diagram showing a conventional rear axle drive device.

FIG. 5 is a diagram showing drive wheels when traveling on a low friction road according to a conventional technique.

[Explanation of symbols]

 10 propeller shaft 12 divider gear 13 idle gear 14 spur gear 15, 21, 32, 37 drive pinion 16 ring gear 17, 34 sliding clutch 20 sub-propeller shaft 30 gear 31, 36 solenoid valve 33 transmission gear 40 rear-front shaft differential unit 42 , 43 rear front wheels 44, 45 rear two wheels 46 rear two-wheel single-wheel drive gear set section

Claims (2)

[Scope of utility model registration request] 1. A drive device for a rear two-axle vehicle having a drive mechanism for the rear two shafts and an interrupting mechanism for the drive force to the rear-to-rear shaft, wherein a sub-propeller shaft extending a divider gear for driving the rear front shaft, A drive pinion attached to the sub-propeller shaft, a gear that meshes with the drive pinion and is connected to the shaft of one of the two rear shafts, and a clutch device provided in the middle of the sub-propeller shaft. A drive device for a rear two-axle vehicle that features. 2. A drive device for a rear two-axle vehicle having a drive mechanism for the rear two shafts and an interrupting mechanism for the drive force to the rear-end shaft, wherein a first drive pinion attached to a propeller shaft and the first drive pinion. A ring gear that meshes with the rear and front shaft differential gears, a transmission gear that substantially faces the first drive pinion and meshes with the ring gear, and a sub-propeller that is attached to the transmission gear and extends rearward to the shaft side. A shaft, a second drive pinion attached to the sub-propeller shaft, a gear that meshes with the second drive pinion, and is connected to the shaft of one of the rear wheels of the rear-end shaft, and provided in the middle of the sub-propeller shaft. A drive device for a rear two-axle vehicle, comprising: a clutch device.