JPH0626335A - Power transmission for engine - Google Patents

Abstract

PURPOSE:To improve the cooling performance of a driving system in the structure of disposing an engine body and the driving system longitudinally and integrally at an engine housing. CONSTITUTION:A front crankcase part 18a for accommodating an engine body 11, and a rear transmission case part for accommodating a driving system 17 including a transmission are integrated to form an engine housing 18. The transmission case part of this engine housing 18 is extended laterally from the side end face of an oil pan 26 so as to heighten cooling performance by travel air.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine power transmission device in which an engine body and a drive system including a transmission are integrally installed in a common engine housing.

[0002]

2. Description of the Related Art Conventionally, when an engine is mounted on a vehicle, an intermediate shaft is arranged in parallel with the crankshaft, as shown in US Pat. No. 4,915,070. A structure in which power is transmitted to the engine, a clutch and a transmission are arranged on the side of the engine body, and the power is output to both sides via a differential device is also disclosed in Japanese Patent Laid-Open No. 31655/1989. There is known a structure in which a transmission and a differential device are installed on the rear side of an engine main body in parallel with the crank shaft.

[0003]

However, when a drive system such as a transmission or a differential device is installed parallel to the crankshaft of the engine body as in the above-mentioned prior art, this drive system is located behind the engine body. Therefore, the cooling effect by the traveling wind cannot be sufficiently obtained, and an external oil cooler for cooling the mission oil due to an increase in temperature is required, which is disadvantageous in terms of space, cost and weight.

That is, when the engine body and the drive system are arranged in front and rear, the engine body becomes vertically long due to the structure of the cylinder head, the cylinder block, and the oil pan, and the vertical space of the engine room is narrow,
It is difficult to arrange the drive system below the engine body, so that the driving wind that directly acts on the drive system located behind the engine body is small, and the housing for the engine body and the drive system is If they are integrated, the surface area with which the cooling air comes into contact also decreases, further lowering the cooling performance, and raising the temperature causes the above-mentioned problems.

In view of the above circumstances, it is an object of the present invention to provide an engine power transmission device which improves the cooling performance of a drive system arranged behind the engine body.

[0006]

In order to achieve the above object, a power transmission device for an engine according to the present invention includes an engine main body and a drive system including a transmission in a front portion of a vehicle in parallel with each other in a common engine housing. And the engine main body is installed in front of the drive system, the transmission case in the engine housing for accommodating the drive system is located behind the crankcase part of the engine main body and laterally from the side end surface of the oil pan. It is configured by being extended to.

[0007] Further, the auxiliary machinery of the engine body is arranged in an arc along with the drive system around the crankshaft in the side portion where the transmission case portion extends laterally from the oil pan, and the engine body is tilted. It is preferable to install them.

[0008]

In the power transmission device for an engine as described above, the crankcase portion for accommodating the engine body and the transmission case portion for accommodating the drive system are integrally formed as an engine housing to achieve compactness, and By extending the above-mentioned mission case part behind the crankcase part of the engine body and laterally from the side end surface of the oil pan, the traveling wind directly acting on the mission case part from the front increases to cool the drive system. The property is improved. As a result, the temperature rise of the drive system is suppressed and the external oil cooler is not required to be installed, and the installation space, cost and weight can be reduced.

Further, if the auxiliary machines of the engine are arranged in an arcuate shape at appropriate intervals and the auxiliary machines are used as an integrated guide of traveling wind, the cooling performance can be further improved, and moreover,
When the engine body is installed in an inclined manner, the traveling wind that passes through the lower portion of the engine body and acts on the mission case increases, and the cooling performance can be further improved.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a schematic side structure of an engine including a power transmission device according to an embodiment. In this example, a horizontal FF engine is shown, and the vehicle is mounted so that the left side of the drawing is the front of the vehicle. 2 is a front view seen from diagonally above in FIG. 1, and FIG.
FIG.

The engine 10 has an engine body 11 having a cylinder head 12 and a drive system 17 including a transmission 15 and a differential device 16 arranged in an engine housing 18 which is integrated. In the engine body 11, a crankshaft 21 is installed along the lateral direction of the vehicle, and an upper portion of the engine body 11 is inclined rearward. Further, balancer shafts 22 and 23 are arranged on the engine body 11 at both upper sides of the engine housing 18 for the purpose of reducing engine vibration. On the other hand, behind the engine body 11, the transmission shaft 24 of the transmission 15 is parallel to the crank shaft 21.
And a drive shaft 25 (differential shaft) extending from the differential device 16 to both sides.

The engine housing 18 comprises a front crankcase portion 18a forming a cylinder block portion of the engine body 11 and a rear transmission case portion 18b for accommodating the drive system 17, and the engine housing 18 Is vertically divided into a main housing 19 and a lower housing 20 at a position passing through the center of the crankshaft 21, and an oil pan 26 is attached to the lower portion of the lower housing 20. Main housing 19 and lower housing 20 above
The bearing portion 27 of the crankshaft 21 is formed on the split mating surface with the bearing surface 29, and the bearing portion 29 of the drive shaft 25 of the drive system 17 is formed on the rear side so as to support the respective rotary shafts. Has been done.

That is, the upper surface of the lower housing 20 is, as shown in FIG. 3, a crankcase portion 18a having bearing portions 27 for supporting the crankshaft 21 of the engine body 11 between both ends and between the cylinders, and a gear of the transmission 15. The lower portion of the row portion and the mission case portion 18b surrounding the lower half of the differential device 16 are integrally formed, and the lower surface is smaller than the opening portion on the upper surface and has an opening shape that matches the upper surface shape of the oil pan 26 described later. .

Further, at one end of the engine body 11,
A clutch 31 is arranged in an extension portion of the crankshaft 21, and an output of the clutch 31 is input to a transmission shaft 24 of the transmission 15 via an outer gear 32 (see FIG. 3).
The output after shifting is output to drive the front wheels from the drive shafts 25 on both sides which extend laterally in the lower rear part through the differential device 16. When driving the rear wheels, a center differential may be arranged adjacent to the differential device 16 (front differential), and a propeller shaft may be installed from the center differential to the rear via a transfer. Is.

On the other hand, the shape and installation position of the oil pan 26 are in the vicinity of the drive shaft 25 from the bottom of the crankcase portion 18a of the engine housing 18 to the lower portion of the transmission case portion 18b of the rear drive system 17 in the front-rear direction. It is extended to and installed. Further, in the vehicle width direction along the crankshaft 21 of the engine body 11, the oil pan 26 is narrower than the width of the engine housing 18, and particularly the left side portion is short and is formed closer to the clutch 31 side from the center portion. In other words, the mission case portion 18b that houses the differential device 16 extends laterally from the side end surface of the oil pan 26.

Further, depending on the tilt mounting of the engine housing 18, on the bottom surface of the lower housing 20, the transmission case portion 18b behind the front crankcase portion 18a.
The bottom of the oil pan 26, which is formed low and is fastened to the bottom of the inclined lower housing 20, is formed such that the front part is deep and the rear part is shallow, and the bottom face is a substantially horizontal surface in the mounted state.

Further, the engine 10 is provided with various auxiliary machines. This auxiliary machine is mainly arranged in the left side portion of the oil pan 26 where the space of the side portion of the oil pan 26 where the mission case portion 18b is extended is open, and is fixed to the end portion of the crankshaft 21. Crank pulley 21
Driven by a belt 36 hung from a. That is, in the front part of the engine housing 18, an alternator 37 is installed in the upper part and a water pump 38 is installed in the lower part, and a compressor 39 for an air conditioner is arranged in the lower center part of the engine housing 18, and the pulleys 37a to 39a are provided.
The belt 36 is hung on and driven by the
38, 39 and differential device 16 (drive shaft 2
5) is arranged in an arc shape with the crankshaft 21 as the center. The crankshaft 21 and the air conditioner compressor 39
An idler 40 is interposed between the and. Further, a pipe 41 for supplying cooling water is connected to the upper part of the engine housing 18 (cylinder block) of the engine body 11 from the water pump 38.

On the other hand, from the crankshaft 21, the camshaft 43 above the cylinder head 12 and the engine housing
18 A transmission mechanism for driving the balancer shafts 22 and 23 on the upper part is formed. That is, first, the intermediate shaft 45 is driven from the crankshaft 21 by the first chain 44, the camshaft 43 above the intermediate shaft 45 is decelerated by the second chain 46, and the balancer below the intermediate shaft 45 is driven. Axis 2
The second chain 23 and the second chain 23 are configured to be accelerated and driven.

A clutch 31 is installed on the right side of the engine housing 18.
An oil pump 50 is installed below the oil pan 26 on the side of the oil pan 26, and supplies the oil in the oil pan 26 to each part.

With the above structure, the engine 10
The traveling wind that flows in from the front along with the traveling of the vehicle equipped with is to cool the front side as a whole, but in particular, as shown by the arrow C in each figure, a part of this traveling wind Are collectively guided by the water pump 38, the auxiliary body of the air conditioner compressor 39, and the pulleys 38a, 39a, pass through the side of the oil pan 26, and are located behind the crankcase portion 18a of the engine housing 18 in the mission case. Department
It concentrates on 18b and improves the cooling performance of the drive system 17.

Further, a compressor 39 for an air conditioner is directly attached as an auxiliary machine to a place located below the crankshaft 21 of the engine main body 11 and the drive shaft 25 of the differential device 16 of the drive system 17 at a position located below. By forming a triangle, it is possible to maximize the cross-sectional rigidity of the vibration node of the differential device 16, and by utilizing the rigidity of the auxiliary machinery, deterioration of vibration characteristics due to bending vibration during engine operation and bearing deformation The problem of reduced reliability can be improved.

[Brief description of drawings]

FIG. 1 is a schematic side view of an engine including a power transmission device according to an embodiment of the present invention.

FIG. 2 is a schematic front view seen from diagonally above in FIG.

FIG. 3 is a cross-sectional view taken along line AA of FIG. 1 in which auxiliary machinery is omitted.

[Explanation of symbols]

 10 Engine 11 Engine body 15 Transmission 16 Differential device 17 Drive system 18 Engine housing 18a Crank case part 18b Mission case part 21 Crank shaft 24 Mission shaft 25 Drive shaft 26 Oil pan 37-39 Auxiliary equipment

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akutagawa et al. 3-1, Shinchi Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda Co., Ltd. (72) Inventor Junichi Okita 3-3 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Mazda Corporation Within

Claims (4)

[Claims] 1. An engine main body and a drive system including a transmission are arranged in parallel to each other in a front part of a vehicle and integrally in a common engine housing, and the engine main body is installed in front of the drive system. A power transmission device for an engine, characterized in that a transmission case portion for accommodating a drive system in the above is extended rearward of a crank case portion of an engine body and laterally from a side end surface of an oil pan. 2. The power transmission device for an engine according to claim 1, wherein the drive system is provided with a transmission at an upper portion and a differential device at a lower portion. 3. The auxiliary machine of the engine body is characterized in that the mission case is arranged in a circular arc along with a drive system around a crankshaft in a lateral portion extending laterally from an oil pan. The power transmission device for an engine according to claim 1. 4. The power transmission device for an engine according to claim 1, wherein the engine body is installed such that an upper portion thereof is inclined rearward.