JPH01167406A - Cylinder block of v-type engine - Google Patents

Abstract

PURPOSE:To effectively utilize the dead space and increase rigidity by forming a recessed part for facilitating the slip-off of a metal mold on the transmission side of the dead space and utilizing said recessed part as blow-bye gas expansion chamber and forming ribs. CONSTITUTION:In a dead space 6, a fan-shaped recessed part 11 opened on the joint flange surface 9 of a transmission 7 is formed. Further, in the recessed part 11, ribs 12-14 are formed. Further, in the recessed part 11, a blow-bye gas introducing passage 21 for connecting a crankcase 2 and the recessed part 11, blow-bye gas discharge passage 22 for connecting an oil separator chamber 25 between the banks and the recessed part 11, and an oil return passage 23 for connecting the recessed part 11 and the crankcase 2 are opened. Therefore, the dead space 6 can be effectively utilized as a blow-bye gas expansion chamber, and the manufacture of the metal mold of a cylinder block is facilitated, and rigidity can be increased.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a cylinder block for a V-type engine, and particularly to one made of a light alloy.

(Prior Art) Generally, in a V-type engine, two banks of cylinders are arranged offset in the direction of the engine output shaft. In that case, a dead space without a cylinder is formed at the end of each bank. In order to make the engine more compact by effectively utilizing this dead space, conventionally, as disclosed in Japanese Patent Application Laid-open No. 194018/1983,
It is known that oil return passages communicating with the upper surface of the cylinder head are provided in the dead spaces of the two banks, and oil accumulated on the upper surface of the cylinder head is returned to the oil pan via the oil return passage. . Furthermore, in Japanese Patent Application Laid-Open No. 62-170715, a blow-by gas passage is provided in the dead space to communicate the rocker arm chamber in the cylinder head with the crankcase chamber, and the blow-by gas in the crankcase chamber is transferred through the blow-by gas passage. A device is disclosed in which the rocker arm is guided into the rocker arm chamber. Furthermore, Japanese Patent Application No. 62-5673 filed by the present applicant describes a device in which an expansion chamber as a blow-by gas passage is provided in the dead space.

(Problems to be Solved by the Invention) By the way, when the cylinder block of a V-type engine is made of a light alloy to reduce its weight, the cylinder block is manufactured using a mold, such as by high-pressure die casting. It turns out.

However, if a cylinder block is manufactured using a mold in this way, a core cannot be used, so as mentioned above, a closed chamber such as an oil return passage or a blow-by gas passage must be integrally provided in the dead space. This makes it difficult to make molds.

Furthermore, when a transmission is connected to one end of the cylinder block in the direction of the engine output shaft, it is necessary to increase the joint rigidity between the cylinder block and the transmission as much as possible.

Furthermore, as described above, when an expansion chamber of a blow-by gas passage is provided in a dead space, there is a demand for improving oil separation performance as much as possible.

The present invention was developed in view of the above, and its purpose is to make the chamber provided in the dead space open in the direction in which the mold exits, thereby facilitating the production of molds for cylinder blocks. A rib is formed in this chamber to increase the joint rigidity between the cylinder block and the transmission, and the rib is used as a partition wall of the blow-by gas expansion chamber.

(Means for Solving the Problems) In order to achieve the above object, in the present invention, a recess is provided on the transmission side of the dead space so that the mold can be easily removed, and the recess is used as a blow-by gas expansion chamber. A rib is formed extending in the radial direction from the output shaft side to increase the rigidity around the dead space, and the blow-by gas expansion chamber is partitioned by the rib.

Specifically, the solution taken by the present invention is made of a light alloy, and the cylinders of two banks are shifted in the direction of the engine output shaft to form a dead space without a cylinder at the end of each bank. The cylinder block of a V-type engine is assumed to have a transmission connected to one end in the direction of the output shaft. In contrast to this, a recess opening toward the joint surface of the transmission is formed in the dead space in the bank where the dead space is formed closer to the transmission. A rib is formed in the recessed portion to extend halfway in the radial direction of the engine output shaft and toward the transmission joint surface.

Furthermore, a blowby gas introduction passage for introducing blowby gas into the recess, a blowby gas discharge passage for discharging blowby gas from the recess, and an oil return passage for returning oil from the recess to the crankcase are opened in this recess. It is configured to do this.

(Function) With the above configuration, in the present invention, a recess is formed in the dead space of the bank.1 A blow-by gas introduction passage, a blow-by gas discharge passage, and an oil return passage are opened in the recess. This allows the engine to be made more compact while making effective use of dead space.

In this case, since the recess is open to the joint surface side of the transmission, manufacturing of the mold for the cylinder block is facilitated.

In addition, a rib is formed within this recess that extends halfway in the radial direction of the engine output shaft and toward the transmission joint surface, increasing the rigidity around the dead space and increasing the joint rigidity between the cylinder block and the transmission. At the same time, since this rib serves as a partition wall of the blow-by gas expansion chamber, the oil separation performance in the recess is enhanced.

(Example) Embodiments of the present invention will be described below based on the drawings.

1 to 3 show a cylinder block B of a V-type six-cylinder engine according to an embodiment of the present invention. The cylinder block B is made of aluminum alloy. and,
Three cylinders 1.degree. 1.1 are formed in the left bank L and right bank R of the cylinder block B, respectively, and a crankcase 2 is formed inwardly. The cylinders 1 and 1.1 of these two banks L and H are arranged offset in the direction of the engine output shaft 3 (vertical direction in Fig. 1), and cylinder 1 is located at the end of each bank L and H.
Dead spaces 5 and 6 are respectively formed. Furthermore, a transmission 7 is joined to the rear end of the cylinder block B (lower end in FIG. 1).

As shown in FIGS. 2 and 3, the dead space 6 in the bank (right bank R) where the dead space 5.6 is formed closer to the transmission 7 is located on the side of the joining flange surface 9 of the transmission 7. Four open parts 11 are formed. That is, a joining flange surface 8 for joining the transmission 7 is formed at the rear end of the cylinder block B, and a joining flange surface 8 on the engine output shaft 3 side of the joining flange surface 8 in the right bank R is formed when viewed from the direction of the output shaft 3. Four fan-shaped parts 11 are formed which are recessed inwardly of the cylinder block B.

Furthermore, ribs 12 to 14 are formed in the recess 11 and extend halfway in the radial direction of the engine output shaft 3 and toward the joining flange surface 9 of the transmission 7. One of the ribs 12 extends halfway from the engine output shaft 3 side to the joint flange surface 9 side, and the other ribs 13 and 14 extend halfway from the joint flange surface 9 side to the engine output shaft 3 side. These ribs 12
The inside of the recess 11 is partitioned by 14 to form a passage through which the blow-by gas meanderes. A cover member 15 is attached to the rear end of the cylinder block B to airtightly close the recess 11, so that the recess 11 can function as an expansion chamber for blow-by gas.

Further, a blow-by gas introduction passage 21 connecting the crankcase 2 and the recess 11 is opened at one end of the meandering passage of the recess 11, and an oil supply passage 21 between the recess 11 and the bank is opened at the other end of the meandering passage of the recess 11. A blow-by gas discharge passage 22 connecting to the separator chamber 25 is open.

Further, an oil return passage 23 that connects the recess 11 and the crankcase 2 is opened at the lowest part of the recess 11 . Therefore, the blowby gas introduced from the crankcase 2 into the four part 1 through the blowby gas introduction passage 21 is expanded in the four part 11 to separate oil from the blowby gas, and the blowby gas after oil separation is transferred to the blowby gas discharge passage. The oil separated from the blow-by gas is discharged into the oil separator chamber 25 via the oil return passage 22 and returned to the crankcase 2 via the oil return passage 23.

Therefore, in the above embodiment, since the cylinder block B is made of an aluminum alloy, it is possible to reduce the weight.

In addition, a recess 11 is formed in the dead space 6 of the bank R, and a blow-by gas introduction passage 21, a blow-by gas discharge passage 22, and an oil return passage 23 are opened in the recess 11, so that the recess 11 functions as a blow-by gas expansion chamber. This makes it possible to make the engine more compact while making effective use of the dead space 6.

In this case, since the recess 11 is open to the joint surface 9 side of the transmission 7, manufacturing of the mold for the cylinder block B becomes easy.

In addition, since ribs 12 to 14 are formed in this recess 11 to extend halfway in the radial direction of the engine output shaft 3 and toward the transmission joint surface 9, the rigidity around the dead space 6 is increased and the cylinder block B is The joint rigidity with the transmission 7 is increased. Moreover, since the ribs 12 to 14 serve as partition walls of the blow-by gas expansion chamber, the oil separation performance in the recess 11 is improved.

(Effects of the Invention) As explained above, according to the cylinder block of the V-type engine of the present invention, the cylinder block is formed of a light alloy, and the dead space in the bank where the dead space is formed closer to the transmission is located on the joint surface of the transmission. forming a recess opening on the side, and forming a rib in the recess extending halfway in the radial direction of the engine output shaft and extending toward the transmission joint surface side;
Since the blow-by gas introduction passage, the blow-by gas discharge passage, and the oil return passage were opened in the recess, a recess was formed in the dead space of the bank, and the blow-by gas introduction passage, the blow-by gas discharge passage, and the oil return passage were opened in the recess. Therefore, the dead space can be effectively used as a blow-by gas expansion chamber to make the engine more compact, while also making it easier to manufacture cylinder block molds, improving the joint rigidity between the cylinder block and transmission, and improving blow-by gas oil separation performance. It is possible to improve the

[Brief explanation of the drawing]

The drawings illustrate an embodiment of the present invention, and FIG. 1 is a plan view of the cylinder block, FIG. 2 is a rear view of the cylinder block, and FIG. 3 is a longitudinal cross-sectional view of a portion of the cylinder block. B...Cylinder block, L...Left bank, R...
・Right bank, 1... Cylinder, 3... Engine output shaft, 5° 6... Dead space, 7... Transmission, 9... Joint surface, 11... Recess, 12-1
4... Rib, 21... Blow-by gas introduction passage, 2
2... Blow-by gas discharge passage, 23... Oil return passage.

Claims (1)

[Claims] (1) It is made of light alloy, and the cylinders of the two banks are shifted in the direction of the engine output shaft to form a dead space with no cylinders at the end of each bank, and the transmission is connected to one end in the direction of the engine output shaft. In the cylinder block of a V-type engine, a recess opening toward the joint surface of the transmission is formed in the dead space in the bank where the dead space is formed closer to the transmission, and a recess is formed in the recess that opens toward the joint surface of the transmission, and the engine output shaft extends halfway in the radial direction of the engine output shaft. A blow-by gas introduction passage for introducing blow-by gas into the recess, a blow-by gas discharge passage for discharging blow-by gas from the recess, and a rib that extends toward the transmission joint surface side, and a blow-by gas discharge passage for discharging blow-by gas from the recess, and a blow-by gas discharge passage for discharging the blow-by gas from the recess, and oil from the recess to the crankcase. A cylinder block for a V-type engine, characterized in that an oil return passage for returning oil is opened in this recess.