JP2000062426A - Suspension for traveling vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the stability of a vehicle by lowering the center of gravity of the vehicle and to mount an equipment such as an engine in a compact manner. SOLUTION: This suspension is driven by an engine 2 via a transmission 4 fixed to a car body 1, suspended on the car body 1 via a differential gear 5 having a case 5a fixed to the car body 1 and a buffer such as a leaf spring 8, and caused to be de dion type by an axle 9 for rotatably supporting left and right wheels 6 and 6 and a drive shaft for connecting the left and right wheels 6 and 6 with the differential gear 5. In this case, the case 5a of the differential gear 5 is directly connected to the transmission 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a suspension of a traveling vehicle, and more particularly to a suspension of a traveling vehicle such as a mobile crane.

[0002]

2. Description of the Related Art In an axle suspension of a traveling vehicle, the left and right wheels are joined by one axle, and the axles are attached to the vehicle body through springs. It is often used as a suspension for large and heavy vehicles such as.

Among axle suspensions, a differential gear / axle integrated suspension 50 (first prior art) as shown in FIGS. 7 and 8 has an axle 52 integrally formed with a case of a differential gear 51 and a leaf spring. It is mounted on the vehicle body 54 so that it can be vertically vibrated (upper amplitude h) by 53. Further, the differential gear 51 drives the left and right wheels 56, 56 via a drive shaft 55 in the axle 52. Therefore, the differential 51 and the transmission 57, which are fixed to the vehicle body 54, are not connected to the propeller shaft 58.
Are connected via. The transmission 57 is driven by a propeller shaft 62 via a torque converter 61 by an engine 60 fixed to the vehicle body 54.

In a Dodion type suspension 70 (second prior art) as shown in FIGS. 9 and 10, a case 71a of a differential gear 71 is attached to a vehicle body 74 by a bolt 73 via a mounting member 72. Axle 75 is coil spring 7
It is suspended on the vehicle body 74 by six and two link mechanisms 77, 77. The transmission 80 fixed to the vehicle body 74 drives the differential gear 71 via the propeller shaft 81. Axle 75
The left and right wheels 79, 79, which are rotatably supported by the shaft, are driven by a differential 71 via a drive shaft 78. The transmission 80 is driven by a propeller shaft 84 via a torque converter 83 by an engine 82 fixed to a vehicle body 74.

[0005]

However, the above-mentioned prior art has the following problems. (1) In the differential gear / axle integrated suspension 50, a space for at least the upper amplitude h is required between the vehicle body 54 and the differential gear 51. For this reason, the ground clearance H1 at the lower end of the vehicle body 54 must be added to the sum of the minimum ground clearance H0 and the height H2 of the differential gear 51 by an amplitude h higher than that. That is, the height of the center of gravity of the portion above the vehicle body 54 that occupies most of the total weight of the vehicle (substantially equal to the center of gravity of the vehicle) is higher than that when the differential gear 51 is fixed to the lower end of the vehicle body 54 as in the Dodion type. It becomes higher by the amplitude h. For this reason, the vehicle stability is lowered in a work vehicle such as a mobile crane that carries out lifting work. (2) With the Dodion suspension 70, the axle 75
When attaching the vehicle to the vehicle body, not only the coil spring 76 but also the link mechanism such as the link 77 and the propeller shaft 8 are attached.
Since 1 is required, the number of parts increases and the cost increases.

The present invention has been made in view of the above problems. The center of gravity of the vehicle is lowered to improve the stability of the vehicle, and the number of parts is reduced to improve the assemblability and maintainability. It is an object of the present invention to provide a traveling vehicle suspension which is designed to reduce costs.

[0007]

In order to achieve the above object, a suspension of a traveling vehicle according to a first invention of the present application is driven by an engine via a transmission fixed to a vehicle body, and Drive that connects the differential gear with the case fixed to the vehicle body, the axle that is suspended on the vehicle body via a shock absorber such as a leaf spring, and that rotatably supports the left and right wheels, and the left and right wheels and the differential gear In the suspension of the traveling vehicle that was made a dodion type with the axis,
The feature is that the case of the differential gear is directly fixed to the transmission.

According to the first aspect of the invention, since the case of the differential gear is directly fixed to the transmission, there is no relative movement between the vehicle body and the differential gear. Therefore, the space for the amplitude of the differential gear as in the first conventional technique is unnecessary. Therefore, it is possible to improve the stability of the vehicle by lowering the vehicle body by the amplitude and lowering the center of gravity of the portion above the vehicle body that occupies most of the total weight of the vehicle (substantially equal to the center of gravity of the vehicle). Further, a propeller shaft between the differential gear and the transmission is not required, and the structure can be made compact accordingly. Further, since the link mechanism and the propeller shaft in the dodion type suspension shown in the second prior art are not required, the number of parts is reduced, the assemblability and maintainability are improved, and the cost is reduced.

A suspension of a traveling vehicle according to a second invention of the present application is characterized in that, in the first invention, the engine and the transmission are integrally fixed.

According to the second invention, in addition to the function and effect of the first invention, since the engine and the transmission are integrally fixed, a propeller shaft for connecting them is not required, and the assembling property is reduced by reducing the number of parts. And maintainability can be improved. Further, the mounting space for the engine and the transmission is reduced, and the traveling vehicle is made compact, which facilitates miniaturization.

A suspension for a traveling vehicle according to a third invention of the present application is characterized in that, in the second invention, the differential gear is arranged below the engine.

According to the third invention, in addition to the function and effect of the second invention, since the differential gear is further arranged below the engine, the installation space of the engine, the transmission, the differential gear, the axle and the drive shaft can be made compact. Since the vehicle length is reduced, the traveling vehicle can be downsized.

In the traveling vehicle suspension according to the fourth invention of the present application, in the third invention, the portion of the engine oil pan located above the differential and the axle is formed shallower than the other portions, and is formed shallower than the other portions. It is characterized in that the differential and the axle are arranged in the vicinity of the lower part of the oil pan.

According to the fourth aspect of the invention, in addition to the action and effect of the third aspect of the invention, the vehicle body can be lowered until the lower side of the portion of the oil pan formed shallower comes close to the differential. Therefore, the center of gravity of the portion above the vehicle body (which is almost equal to the center of gravity of the vehicle) that occupies most of the total weight of the vehicle is lowered, so that the stability of the vehicle is further improved.

A suspension of a traveling vehicle according to a fifth aspect of the invention is characterized in that, in any one of the first to fourth aspects of the invention, the lower surface of the axle is arranged above the lower surface of the differential.

According to the fifth aspect of the invention, in addition to the operation and effect of any of the first to fourth aspects of the invention, since the lower surface of the differential gear has a minimum ground clearance, the position of the center of gravity of the vehicle at a predetermined height from the differential gear is increased. It becomes low and the stability of the vehicle is improved. That is, when the lower surface of the axle is at the minimum ground clearance as in the conventional case, the position of the center of gravity of the vehicle at a predetermined height from the differential is also increased by the amount that the lower surface of the differential gear is higher than the minimum ground clearance. The invention can be lower than this.

A suspension of a traveling vehicle according to a sixth aspect of the invention is characterized in that in any one of the first to fifth aspects of the invention, the traveling vehicle is a mobile crane.

According to the sixth aspect of the invention, when the suspension according to any one of the first to fifth aspects of the invention is applied to a mobile crane, the center of gravity of the vehicle can be lowered and the vehicle stability is improved. Therefore, in the case of a mobile crane in which a large overturning moment is likely to act on the vehicle body, the effect of improving its stability is extremely large. In addition to the engine and transmission, a remarkably large number of devices such as winches are mounted on the vehicle body of the mobile crane. However, since the transmission and the differential gear are integrally fixed from the engine, by arranging them as a counter balance and arranging them at a predetermined position in consideration of weight balance,
Weight balance can be improved. Further, since the transmission and the differential gear are integrally fixed from the engine, it is easy to secure an installation space for the above-mentioned devices, and the degree of freedom of arrangement thereof is improved. Therefore, maintenance and inspection and assemblability are improved.
Further, since the transmission and the differential gear are integrally fixed from the engine, the vehicle length is shortened, and the center of gravity of the vehicle is lowered and the vehicle height is lowered as described above. Therefore, the maneuverability of the mobile crane is improved and the work efficiency is improved.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments according to the present invention will be described in detail below with reference to FIGS. 1 and 2, an engine 2 is fixed to a vehicle body 1 of a mobile crane 10, and a torque converter 3 and a transmission 4 are integrally fixed to the engine 2 in order. The case of the differential gear 5 is fixed to the transmission 4, and the drive system of the wheels 6 mounted first from the differential gear 5 is composed of a dodion type suspension 7 which will be described in detail later with reference to FIGS. It is suspended on the vehicle body 1 via 8.

Referring to FIG. 3 showing the first embodiment of the present invention, an engine 2 is fixed to a vehicle body 1, and a torque converter 3 and a transmission 4 are integrally fixed to the engine 2 in that order. The case 5 a of the differential gear 5 is directly fixed to 4. As shown in FIGS. 4 and 5, the left and right wheels 6, 6 are attached to the axle 9 suspended from the vehicle body 1 by the leaf springs 8.
6 is rotatably supported. The axle 9 is installed at substantially the same height as the center of the wheel 6, and the lower surface of the axle 9 is arranged above the lower surface of the differential gear 5. The wheels 6 are connected to the differential 5 via a drive shaft 11 composed of a universal joint. Also, the car body 1
An oil damper 12 for damping the vibration of the axle 9 by the leaf spring 8 is mounted between the shaft 9 and the axle 9.

The case 5a of the differential 5 is fixed to the engine 2 side of the transmission 4 and is arranged below the oil pan 2a of the engine 2. The portion 2b of the oil pan 2a of the engine 2 located above the differential gear 5 and the axle 9 is formed shallower than the other portions, and the differential gear 5 is arranged close to the lower portion of the shallow formed portion 2b of the oil pan 2a. To do.

The operation of the first embodiment will be described. Differential 5
Since the case 5a is fixed directly to the transmission 4, there is no relative movement between the vehicle body 1 and the differential 5. Therefore, the space for the amplitude h of the differential gear 5 as in the first conventional technique (see FIG. 7) is unnecessary. Therefore, since the vehicle body 1 is arranged lower by the amount of this amplitude h, the center of gravity of the portion above the vehicle body 1 which occupies most of the total weight of the vehicle (substantially equal to the center of gravity of the vehicle) is also lowered and the stability of the vehicle is improved. . Further, the propeller shaft as in the first conventional technique (see FIG. 7) is not required between the differential 5 and the transmission 4, and the structure can be made compact accordingly. Further, since the link mechanism and the propeller shaft as in the second conventional technique (see FIG. 9) are unnecessary, the number of parts is reduced and the cost can be reduced. Further, since the engine 2 and the transmission 4 are integrally fixed, the propeller shaft as in the first conventional technique (see FIG. 7) is not necessary, and the mounting space for the engine and the transmission is reduced. The vehicle becomes compact and can be miniaturized.

Further, since the differential gear 5 can be arranged below the engine 2, the engine 2, the transmission 4, the differential gear 5, the axle 9 can be arranged.
Also, the drive shaft 11 can be compactly installed in one place. Since the axle 9 is arranged either before or after the differential gear 5, the minimum ground clearance H0 of the mobile crane is determined by the lower end of the differential gear 5. Further, at this time, the axle 9 vibrates in the vertical direction, but since the axle diameter of the axle 9 is smaller than that of the differential gear 5, the swing of the axle 9 is the vibration of the differential gear 5 in the first conventional technique (see FIG. 7). Even if it is the same as the width h, this amplitude h is smaller than the height H2 of the differential gear 5. Therefore, the distance between the lower end of the differential gear 5 and the lower end of the vehicle body 1 can be made substantially equal to the height H2 of the differential gear 5. As a result, the center of gravity of the mobile crane is lowered and the vehicle stability of the mobile crane is improved.

On the vehicle body 1 of the mobile crane, in addition to the engine 2, the torque converter 2 and the transmission 4, a remarkably large number of devices such as winches are mounted. But engine 2
Since the transmission 4 and the differential 5 are integrally fixed,
By arranging these at a predetermined position in consideration of weight balance as a counter balance, the weight balance can be improved. Furthermore, since the transmission and the differential gear are integrally fixed to the engine, it is easy to secure a space for installing the above-mentioned devices, and the degree of freedom in their arrangement is improved. Therefore, the maintenance and inspection of the above-mentioned equipment and the assemblability are improved.

Returning to FIG. 3, since the case 5a of the differential 5 is fixed to the engine 2 side of the transmission 4 and arranged below the oil pan 2a of the engine 2, the distance from the engine 2 to the wheels 6 is shortened. . Therefore, the length of the vehicle is shortened and the steerability is improved. Further, when the differential gear 5 is arranged near the lower portion of the shallowly formed portion 2b of the oil pan 2a, the differential gear 5 approaches the vehicle body 1 and the center of gravity of the vehicle is lowered. Therefore, the stability of the mobile crane during the lifting work is improved. As described above, since the length and height of the vehicle are reduced and the mobility is improved, the work efficiency of the mobile crane is improved.

The second embodiment shown in FIG. 6 is an example in which the torque converter 3 and the transmission 4 are installed separately from each other and connected by a propeller shaft 13. The present embodiment differs from the first embodiment in that the differential 5 is not arranged below the oil pan 2a of the engine 2. Other configurations are similar to those of the first embodiment.

The operation of the second embodiment will be described. Since the differential gear 5 can be arranged above regardless of the position of the oil pan 2a of the engine 2, the distance between the lower end of the differential gear 5 and the lower end of the vehicle body 1 is set to the height H2 of the differential gear 5 as in the above embodiment. Therefore, the center of gravity of the vehicle is lowered and the stability of the mobile crane for lifting work is improved. The differential 5
The case 5a may be fixed to the transmission 4, and may be fixed not to the engine 2 side of the transmission 4 as in the present embodiment but to the opposite side of the engine 2.

[Brief description of drawings]

FIG. 1 is a side view of a mobile crane equipped with a first embodiment of a suspension according to the present invention.

FIG. 2 is a plan view of the mobile crane shown in FIG.

FIG. 3 is a side view of a main part of the first embodiment of the suspension according to the present invention.

FIG. 4 is a plan view of a suspension portion shown in FIG.

FIG. 5 is a front view of FIG.

FIG. 6 is a side view of a main portion of a second embodiment of a suspension according to the present invention.

FIG. 7 is a side view of a main part of a suspension according to a first conventional technique.

8 is a cross-sectional view taken along the line AA of the suspension shown in FIG.

FIG. 9 is a side view (cross-sectional view taken along line CC of FIG. 10) of a main part of a suspension according to a second conventional technique.

10 is a cross-sectional view taken along line BB of the suspension shown in FIG.

[Explanation of symbols]

1 car body 1a mainframe 2 engine 2a oil pan 2b Shallow part 3 Torque converter 4 transmission 5 differential 5a case 6 wheels 7 Dodion suspension 8 leaf spring 9 axles 10 mobile cranes 11 drive shaft 12 oil damper 13 Propeller shaft

Claims (6)

[Claims] 1. A vehicle (1) is driven by an engine (2) via a transmission (4) fixed to the vehicle body (1) and has a case (5a).
It is suspended on the vehicle body (1) via a differential gear (5) fixed to (1) and a shock absorber such as a leaf spring (8), and the left and right wheels (6, 6) are rotatably supported. Axle (9) and left and right wheels
(6,6) and the drive shaft (11) that connects the differential (5) to a Dodion-type vehicle suspension, the case (5a) of the differential (5) is directly attached to the transmission (4). Suspension of traveling vehicle characterized by being fixed. 2. The suspension of the traveling vehicle according to claim 1, wherein the engine (2) and the transmission (4) are integrally fixed. 3. The suspension of the traveling vehicle according to claim 2, wherein the differential gear (5) is arranged below the engine (2). 4. The differential of the oil pan (2a) of the engine (2) in the suspension of the traveling vehicle according to claim 3.
The part (2b) located above (5) and the axle (9) is formed shallower than the other parts, and this oil pan (2a) is formed shallower.
Close to the lower part (2b) of the differential gear (5) and axle.
(9) A suspension of a traveling vehicle, which is provided with. 5. The suspension of the traveling vehicle according to claim 1, wherein the lower surface of the axle (9) is a differential gear.
A suspension for a traveling vehicle, which is arranged above the lower surface of (5). 6. The suspension of the traveling vehicle according to claim 1, wherein the traveling vehicle is a mobile crane.