JPH04127848U - oil-cooled multi-cylinder engine - Google Patents

Abstract

(57) [Summary] (with amendments) [Purpose] To provide an oil-cooled multi-cylinder engine that is simple in structure, produces little vibration and noise, is lightweight, and is inexpensive. [Structure] Cylinder liners 20 are fitted into the plurality of cylinder bores 22 of the crankcase 12, and oil grooves 36 are provided on the outer circumferential surface of the cylinder liners 20 to allow cooling oil to flow, and the cylinder head 14 is cooled by the cooling water. In the engine 10, a cylinder head 14, a crankcase 12, and a ladder frame 16 are integrally connected by a large number of through bolts 18 arranged parallel to the cylinder axis. A total of four through bolts 18 are provided for each cylinder, two on each side of the center plane of the engine 10, of which two through bolts arranged between adjacent cylinders are shared by both cylinders. crank case 1
2 to the cylinder head 14, a minimum number of four through bolts can be used per cylinder.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention relates to an oil-cooled multi-cylinder engine.

0002

[Conventional technology]

In multi-cylinder engines equipped with cylinder liners such as diesel engines for vehicles. , a large number of circumferential grooves or spiral grooves are provided on the outer circumferential surface of the hollow cylindrical liner, and the same circumferential groove Alternatively, an oil-cooled engine that circulates cooling oil in a spiral groove has already been proposed. It is being proposed. (For example, see Utility Model Registration Application No. 60967 of 1988) However, conventional oil-cooled multi-cylinder engines are different from normal water-cooled multi-cylinder engines. Similarly, the cylinder head mounted on the crankcase is connected to many head bolts. Therefore, it is fixed to the crankcase, and also works together with the crankcase to The main bearing cap or ladder frame that holds the rank shaft is It is fixed to the crankcase by a cap bolt that is separate from the cap bolt. Ru. This engine structure uses a large impact force due to the explosion pressure generated within the cylinder. However, since it acts on the crankcase through the head bolt and cap bolt mentioned above, Therefore, from the viewpoint of strength, the wall thickness of the crankcase becomes thicker, which increases the weight. There are defects that tend to generate vibration and noise, and the structure becomes more complicated and expensive, etc. There is a problem.

0003

[Problem that the idea aims to solve]

This invention was devised in view of the above circumstances, and has a simple structure and less vibration and noise. The aim is to provide an oil-cooled multi-cylinder engine that is lightweight and inexpensive. It is.

0004

[Means to solve the problem]

In order to achieve the above object, the present invention provides a plurality of cylinder bores in the crankcase. A cylinder liner is fitted to each cylinder liner, and cooling oil is flowed around the outer circumferential surface of the cylinder liner. In addition to providing oil grooves for passing through each cylinder, The above cylinder head is configured to be cooled by cooling water. and the main bearing that holds the crankcase and crankshaft in the same crankcase. A plurality of bolts approximately parallel to the cylinder axis across the cap or ladder frame The above series can be achieved by drilling through holes and inserting through bolts into each bolt hole and tightening them. head, crankcase, main bearing cap or ladder frame and are integrally connected, and the above-mentioned through bolts A total of four cylinders are arranged, two on each side of the center plane of the engine, and each of the above-mentioned cylinders 4 Two through bolts between adjacent cylinders are arranged in common. The present invention proposes an oil-cooled multi-cylinder engine characterized by the fact that

[0005]

[Effect]

According to this invention, the cylinder head, crankcase and main bearing cover are The cylinder frame or ladder frame is integrally connected with the through bolt, and the cylinder Most of the large impact force due to the internal explosion pressure is carried by the through bolt. This reduces the force acting on the crankcase, reducing its weight from a strength standpoint. It is possible to reduce vibration and noise. Also, the cylinder driver The cylinder head is cooled by oil and the cylinder head by cooling water. Therefore, like a normal water-cooled engine, cooling water is routed from the crankcase to the cylinders. There is no need to drain the fluid between the cylinder head and the crankcase. There is no need to provide water holes in the head gasket. As a result, per cylinder Four through bolts are arranged, and two through bolts between adjacent cylinders are Since it is shared by the cylinder, the cylinder head can be attached with a virtually minimum number of through bolts. Strongly connect the main bearing cap or ladder frame to the main bearing cap or ladder frame. The structure can be combined to simplify the structure and reduce manufacturing costs.

[0006]

【Example】

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The reference numeral 10 in the figure generally refers to an oil-cooled direct injection diesel engine for trucks. 12 is the crankcase of the same engine, 14 is the upper end of the crankcase 12 The cylinder head 16 mounted on the crankcase 12 is mounted on the lower end of the crankcase 12. A publicly known ladder frame or underframe having a substantially ladder-like planar shape, 18 inserts the cylinder head 14, crankcase 12 and ladder frame 16. a large number of through bolts extending parallel to the cylinder axis and tightening them together; 20 is fitted into the cylinder bore portion 22 formed in the crankcase 12, and the whole A hollow cylindrical cylinder liner 24 is fitted into the cylinder liner 20. The piston 26 has one small end attached to a connector connected to the piston 24. The connecting rod 28 is connected to the other large end of the connecting rod 26. A rank shaft 30 extends in the direction of the crank axis near the upper end of the crank case 12. The liner oil supply oil gear 32 formed by the above-mentioned crankcase 12 is A member is formed on the side wall adjacent to the lower part of the liner and extends in the direction of the crankshaft. This is an in-oil gear lary, and the main oil gear lary 32 has the above-mentioned crankshaft. Discharge oil from an oil pump (not shown) driven in conjunction with 28 is supplied, Also, a part of the oil discharged from the oil pump is stored in the liner oil supply gear rally 30. It is supplied directly or via the main oil gear gallery 32.

[0007] The cylinder liner 20 has a radially outward portion at the end on the cylinder head 14 side. A flange portion 34 is provided, and the flange portion 34 is excluded from the flange portion 34 . In the case of the illustrated embodiment, the outer circumferential surface has a large number of holes at appropriate intervals in the cylinder axis direction. A circumferential groove 36 is formed. These circumferential grooves 36 are, for example, As disclosed in detail in Draft Registration Application No. 60967 of 1988, the outer peripheral surface of the liner The cylinder is formed with an angular interval of approximately 180 degrees in the circumferential direction and extends in the cylinder axis direction. vertical oil grooves 38 (parts of which are shown in Figures 3 and 4) on the inlet and outlet sides. Therefore, it is divided into one or more passage groups or an appropriate number of passage groups. Oil gear for above liner lubrication The oil supplied to the rally 30 flows from the horizontal oil supply hole 40 to the top of the vertical oil groove 38 on the inlet side. The oil is supplied to the left and right sides in the circumferential direction, goes around half a turn each, and flows out into the vertical oil groove on the outlet side. Ru. If there are two or more groups of passages, the oil that leaked into the vertical oil groove on the outlet side of the first group continues. enters the vertical oil groove on the inlet side of the second group, and in the same manner, enters the circumferential groove 36 of the lower groups. The oil flows directly from the oil discharge groove 42 provided in the lower part of the outer peripheral surface of the liner. The oil may flow down into the pan or be collected in the oil drain gear 44 shown in dotted lines in FIG. It is collected and flows down into the oil pan. The oil discharge gear rally 44 is Similar to the inner oil supply gear lary 30, the crank axis is located inside the side wall of the crankcase 12. It is formed to extend in the direction. The flange portion 34 of the cylinder liner 20 can be clearly seen in the partially enlarged sectional view of FIG. As shown, its lower surface 34a is connected to the flat upper surface 12 of the crankcase 12. a, and its upper side 34b is covered with a suitable gasket, such as a laminate. It is in contact with the lower surface 14a of the cylinder head 14 through a thin gasket 46. Ru.

[0008] The arrangement pattern of the above-mentioned through bolts 18 is clearly shown in the top plan view of the crankcase in Fig. 3. It is clearly shown. In the figure, reference numeral 48 is a bolt through which the through bolt 18 is inserted. It is a hole. The bolt holes 48 are located on both sides of the center plane O-O of the engine including the cylinder axis. 2 for each cylinder, thus 4 for each cylinder, and adjacent Two bolt holes 48 arranged between the cylinders are common to both cylinders. accordingly , when the number of cylinders of the engine 10 is Z, the number of through bolts 18 is 2Z In the case of the four-cylinder engine shown in the figure, there are only 10, which is the practical minimum number. . As shown in FIGS. 1 and 2, the cylinder head 14 and ladder frame Of course, bolt holes 50 and 52 that are in line with the bolt hole 48 are also drilled in the bolt hole 16. In the illustrated embodiment, the through bolt 18 is inserted into the bolt hole from the ladder frame 16 side. 52, and screw the tightening nut 56 onto the threaded portion 54 on the cylinder head 14 side. By doing so, the cylinder head 14, crankcase 12 and ladder frame are 16 are integrally coupled. Additionally, a crank without the ladder frame 16 described above may be used. The skirt of case 12 is extended downward to the position of the ladder frame. In the case of a Puskat type crankcase, the crankshaft 28 is connected to the crankcase 12. The bearing portion 58 (see FIG. 2) itself is connected to a well-known main bearing cap (not shown). In this case, the through bolt 18 is It is inserted upward through the bolt hole drilled in the ring cap, and is inserted into the crankcase 12. the bolt hole 48 of the cylinder head 14 and the bolt hole 50 of the cylinder head 14. By screwing and tightening the tightening nut 56 on the cylinder head 14, The rank case 12 and the main bearing cap are integrally connected. On the other hand, the ladder frame 16 is arranged in large numbers on its outer periphery from the viewpoint of maintaining oil tightness. It is fixed to the lower end of the crankcase 12 by a small diameter auxiliary mounting bolt 60. It is. Further, the reference numeral 62 in FIG. 2 is provided in the bearing portion 58 of the crankcase 12. 64 is an arc-shaped oil groove for supplying oil to the journal portion of the crankshaft 28; It's bread.

[0009] In the above configuration, while the engine 10 is operating, the oil pump (not shown) The oil supplied to the liner oil supply oil gear rally 30 is supplied to a plurality of cylinders. As described above, the inside of the circumferential groove 36 formed on the outer circumferential surface of the cylinder liner 20 is After flowing and cooling the liner, it flows down into the oil pan 64. On the other hand, to the cylinder A cooling water chamber 66 is provided inside the tube 14, and is operated by a water pump (not shown). The coolant pumped under pressure flows through the coolant chamber 66 of the cylinder head 14 and reaches the exhaust port. After cooling the exhaust valves, etc., the water returns to the water pump via the radiator. . The crankcase 12 and cylinder liner 20 are cooled by oil, and the cylinder liner 20 is cooled by oil. The engine head 14 is cooled by cooling water, so it does not operate like a normal water-cooled engine. In addition, there is no need to flow cooling water from the crankcase to the cylinder head 14. accordingly , there is no need to provide a water hole in the gasket 46 for passing cooling water; Since it is only necessary to perform a gas seal, as shown in Figure 4, An extremely simple structure that comes into contact with the upper surface 34b of the flange portion of the flange portion 20 is adopted. be able to. At the same time, in water-cooled engines, the gasket water hole In order to prevent water leakage, 5 to 6 head bolts are required per cylinder. On the other hand, the engine 10 described above uses four through bolts 18 per cylinder. and the two through bolts between adjacent cylinders are shared with the minimum number of through bolts. By arranging the seat 18, the vehicle can be operated without problems.

0010 Furthermore, according to the above configuration, during operation of the engine, the Most of the impact force in the cylinder axis direction due to the explosion pressure is applied to the through bolt 18. It is supported by the crank case 12 and has little effect on the crankcase 12, so it is To realize an engine that is extremely advantageous, lightweight, and has low vibration and noise. I can do it. In addition, the cylinder head 14 is tightened to the crankcase 12. main bearing cap or rudder on the bearing portion 58 of the crankcase 12. - A key that tightens the bearing cap portion 16' of the frame 16 (see Fig. 2). The structure is simpler than that of a normal engine where the Yatsupu bolt is provided separately. This has the advantage of reducing manufacturing costs.

[0011]

[Effect of the idea]

As mentioned above, the oil-cooled multi-cylinder engine according to the present invention has multiple cylinders in the crankcase. A cylinder liner is fitted into each cylinder bore, and a cooling layer is applied to the outer circumferential surface of the cylinder liner. In addition to providing oil grooves for distributing oil for cooling, it is mounted on the above crankcase. In a cylinder head configured to be cooled by cooling water, the upper Hold the cylinder head, crankcase, and crankshaft in the same crankcase. Approximately parallel to the cylinder axis across the main bearing cap or ladder frame. Insert a through bolt into each bolt hole and tighten it. Depending on the above cylinder head, crankcase and main bearing cap or In addition to integrally joining the ladder frame, the above-mentioned through bolts are connected to each cylinder. A total of four pieces are arranged, two on each side of the center plane of the engine in the outer peripheral part, and Two through bolts between adjacent cylinders among the four through bolts in each cylinder above. The structure is simple and generates less vibration and noise. This type of engine is very lightweight and can be provided at low cost, so it is useful in practice. Ru.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing one embodiment of the present invention (I-
(corresponds to a cross section along line I).

[Fig. 2] A cross-sectional view of the engine shown in Fig. 1 (II in Fig. 3).
- corresponds to a cross section along line II).

FIG. 3 is a top plan view of the crankcase in the engine shown in FIG. 1;

FIG. 4 is a partially enlarged sectional view of the cylinder liner attachment portion of the engine shown in FIG. 1;

[Explanation of symbols]

10 engine 12 Crank case 14 Cylinder head 16 Ladder frame 18 Through bolt

Claims (1)

[Scope of utility model registration request] 1. A cylinder liner is fitted into each of a plurality of cylinder bores of a crankcase, and oil grooves are provided on the outer peripheral surface of the cylinder liner for circulating cooling oil, and the cylinders mounted on the crankcase are provided with oil grooves for circulating cooling oil. In a cylinder head configured to be cooled by cooling water, a plurality of bolt holes substantially parallel to the cylinder axis are provided between the cylinder head, the crankcase, and the main bearing cap or ladder frame that holds the crankshaft in the crankcase. By inserting a through bolt into each bolt hole and tightening it, the cylinder head, crankcase, and main bearing cap or ladder frame are integrally connected. A total of four through bolts are arranged, two on each side of the center plane of the engine, in the outer circumference of the cylinder, and among the four through bolts in each cylinder, the two through bolts between adjacent cylinders are arranged in common. Oil-cooled multi-cylinder engine characterized by