JPH0575437U - Partial engine liquid cooling forced air cooling system - Google Patents

Abstract

(57) [Summary] [Purpose] To improve the cooling performance by balancing the air flow to the cylinder head, oil cooler, and cylinder. [Configuration] Cooling air A generated by the flywheel fan 11
Guide with the fan case 14, cylinder 4 and cylinder head 2
Also, the heat is divided into the radiator 16. A cylinder baffle plate (20) is provided on the front side of the cylinder (4) in the fan case (14) and above the flywheel fan (11). This cylinder baffle plate 20 is located above the flywheel fan 11 with its plate start side portion 20a extending toward the case lateral one side portion 14a on which the flywheel fan 11 blows up the cooling air A. The intermediate portion 20b is located above the front surface of the flywheel portion 12 of the flywheel fan 11, and the plate end portion 20c extends toward the case lateral other side portion 14b on the side opposite to the side where the cooling air A is blown up, so that the cooling air A is emitted. The air is guided toward the side surface of the cylinder 4 on the side of the auxiliary combustion chamber 5.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a partly liquid-cooled forced air cooling device for an engine, and more particularly to a technique for guiding cooling air to a cylinder, a cylinder head, and a radiator in a fan case.

[0002]

[Prior Art]

 A conventional example of this type of partially liquid-cooled forced air cooling device is shown in FIGS. The basic structure is such that a centrifugal flywheel fan 111 and a fan case 114 are provided on the front side of the engine body 101, a radiator 116 is provided on the upper front side of the cylinder head 102, and cooling air generated by the flywheel fan 111 is provided. A is guided by the fan case 114 and is divided into the outer circumference of the cylinder 104 / cylinder head 102, the tunnel-type cooling air passage 103, and the radiator 116.

A liquid cooling chamber 118 is formed on the outer periphery of the auxiliary combustion chamber 105 in the cylinder head 102. The auxiliary combustion chamber 105 has a rear side on the side opposite to the side where the flywheel fan 111 blows up the cooling air A. The liquid cooling chamber 118 and the radiator 116 are located at a side portion so as to communicate with each other so that the cooling liquid circulates. In this conventional example, a cylinder baffle plate for guiding the cooling air A to the outer circumference of the cylinder 104 is not provided. In the drawings, reference numeral 107 is an intake port, 108 is an exhaust port, 109 is a main combustion chamber, and 122 is a fin guide provided along the lateral side of the heat-dissipating cylinder fin 104a on the liquid cooling chamber 106 side. It is a wind board.

[0004]

[Problems to be solved by the device]

 In the above-described conventional example, since no cylinder baffle plate for guiding the cooling air A to the outer circumference of the cylinder 104 is provided, the cooling head tries to move upward in the fan case 114 due to the straight inertia of the cylinder head. The amount of air blown to 102 tends to be large, and the amount of air blown to the portion of the lower portion of the sub chamber of the cylinder 104 where the heat load is high becomes insufficient, causing the cylinder 104 to overheat, causing the piston to seize.

Therefore, prior to the present invention as an example of the previous invention, a cylinder baffle plate 120 is attached to the fan case 114 as shown in FIG. The cylinder baffle plate 120 is provided in the inner space of the fan case 114 on the other side of the fan case 114 on the side opposite to the side on which the flywheel fan 111 blows the cooling air A. The cooling air A blown up by 111 is scooped by the cylinder baffle plate 120, and the cooling air A is guided toward the other lateral side near the high heat load portion of the cylinder 104.

However, in the above-described prior art example, the cooling air A blown up by the flywheel fan 111 is scooped by the cylinder air guide plate 120 to guide the air toward the other side of the cylinder 104. Although the cooling effect can be enhanced, the amount of cooling air to the cylinder head 102 is large and the amount of cooling air to the cylinder 104 is not always sufficient. The present invention has been made in consideration of such circumstances, and in this type of partial liquid-cooled forced air cooling device, cooling performance is improved by balancing the air flow to the cylinder head, oil cooler, and cylinder. Let it be a technical subject.

[0007]

[Means for Solving the Problems]

 In order to solve the above problems, the present invention is configured as follows, for example, as shown in FIG. That is, in the basic structure of the conventional example, a cylinder baffle plate 20 is provided at a position in the inner space of the fan case 14 in front of the cylinder 4 and above the flywheel fan 11. The plate-starting-side portion 20a of the plate 20 extends toward the lateral side 14a of the case, which is the side on which the flywheel fan 11 blows up the cooling air A, and is located above the flywheel fan 11, and the plate intermediate portion 20b thereof is provided. Is located above the front surface of the flywheel portion 12 of the flywheel fan 11, and its plate end portion 20c extends toward the other side portion 14b of the case on the side opposite to the side where the cooling air A is blown up and the cooling airflow. It is characterized in that A is introduced to the side surface on the side of the auxiliary combustion chamber 5 of the cylinder 4 and the other side surface thereof.

[0008]

[Operation and effect of the device]

 The present invention has the following actions and effects. On the front surface of the engine body 1, the cooling air A generated by the flywheel fan 11 is split and guided by the fan case 14 to the cylinder 4, the cylinder head 2, and the radiator 16. At this time, the plate start end side portion 20a of the cylinder baffle plate 20 is located above the flywheel fan 11, and takes in a part of the cooling air A blown up toward the cylinder head 2 by the flywheel fan 11.

Next, the plate intermediate portion 20b guides the taken-in cooling air A to the plate end portion 20c of the cylinder air guide plate 20 as it is. Then, the plate end portion 20c guides the cooling air A toward the lateral side surface of the cylinder 4 located on the side opposite to the blowing-up side of the cooling air A on the side of the auxiliary combustion chamber 5 side. As a result, the amount of cooling air that flows around the other side close to the portion of the cylinder 4 where the heat load is high is increased, and the amount of air blown to the cylinder head, oil cooler, and cylinder is balanced, and cooling performance can be improved. ..

[0010]

【Example】

 Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings. FIG. 1 shows an overhead valve diesel engine equipped with a partially liquid-cooled forced air cooling device according to an embodiment of the present invention. FIG. 1 (A) is a longitudinal sectional front view of the main part of the engine, and FIG. 1 is a cross-sectional plan view of the engine of FIG. 1 taken along the line V-V, FIG. 1C is a vertical cross-sectional view of a cylinder baffle plate 20 according to another embodiment, and FIG. 2 is a perspective view of the diesel engine. In the drawings, reference numeral 10 represents the entire partial liquid cooling forced air cooling device according to the present invention, 24 is an intake pipe, 25 is an air cleaner, 27 is an exhaust muffler, 28 is a cell starter, and 30 is a fuel tank. You

The partially liquid-cooled forced air cooling device 10 includes a centrifugal flywheel fan 11 and a fan case 14 provided on the front side of the engine body 1, and an oil cooler (radiator) provided on the upper front side of the cylinder head 2. ) 16, a tunnel type cooling air passage 3 and an oil cooling chamber 18 formed in the cylinder head 2, and a cylinder air guide plate 20 provided in the fan case 14, and the oil cooling chamber 18 is provided. The oil cooler 16 is circulated so that cooling oil circulates, and the cooling air A generated by the flywheel fan 11 is guided by the fan case 14 and the cylinder baffle plate 20 to make the cylinder 4 and the cylinder head 2 The tunnel cooling air passage 3 and the radiator 16 are divided.

The engine body 1 is composed of a cylinder head 2, a cylinder 4, and a crankcase 5. The flywheel fan 11 is fixed to the tip of the crankshaft 6 and covered with a fan case 14. There is. The cylinder baffle plate 20 has a plate start end side portion 20a and a plate end portion 20c fixedly provided on the inner surface of the fan case 14, and in the inner space of the fan case 14, the cylinder baffle plate 20 It is provided on the front side and above the flywheel fan 11.

The plate start end side portion 20a of the cylinder baffle plate 20 extends toward the case lateral one side portion 14a on the side where the flywheel fan 11 blows up the cooling air A, and the upper side of the flywheel fan 11 also. The intermediate plate portion 20b of the cylinder baffle plate 20 is located along the upper front side of the flywheel portion 12 of the flywheel fan 11, and the plate end portion 20c of the cylinder baffle plate 20 has the above-mentioned auxiliary combustion. It is arranged toward the lateral side surface of the heat dissipation cylinder fin 4a on the chamber 5 side. The wind guide surface 21 of the cylinder baffle plate 20 is formed flat as shown in FIG. 1 (B) in order to suppress the generation of turbulence. The shape of the wind guide surface 21 is The shape is not limited to a flat shape, and may be formed by running the ridge 21a along the air guide direction as shown in FIG. 1 (C), for example.

The operation of this embodiment will be described below. On the front surface of the engine body 1, the cooling air A generated by the flywheel fan 11 is guided by the fan case 14 to the cylinder 4, the cylinder head 2, and the radiator 16. At this time, the plate start end side portion 20a of the cylinder baffle plate 20 takes in a part of the cooling air A blown up toward the cylinder head 2 by the flywheel fan 11. Then, the plate intermediate portion 20b guides the taken-in cooling air A as it is to the plate end portion 20c of the cylinder baffle plate 20. The plate end portion 20c of the cylinder baffle plate 20 guides the cooling air A along the side surface of the heat dissipation cylinder fin 104a on the side of the auxiliary combustion chamber 105.

Further, the air guide surface 21 of the cylinder baffle plate 20 is formed flat, or, as shown in FIG. 1C, is formed by running a ridge 21a along the air guide direction. Since turbulence is less likely to occur, the passage resistance to the cylinder head 2 and the radiator 16 is reduced, and the blowing efficiency of cooling air is increased. As a result, the amount of cooling air that flows around the side of the cylinder 4 increases, and the amount of air sent to the cylinder head, oil cooler, and cylinder is balanced, and cooling performance can be improved.

The present invention is not limited to the above-mentioned embodiment, but the wind guide surface 21 is formed flat, the projection 21a is formed, the number of projections 21a is appropriately changed. Can be implemented. Further, in the above-mentioned embodiment, the overhead valve diesel engine having the cylinder type cooling air passage 3 in the cylinder head 2 is exemplified, but the present invention is not limited to this, and cooling air can be pumped to the outer periphery of the cylinder head. It is not necessary to say a lot that it can be implemented with other appropriate changes.

[Brief description of drawings]

FIG. 1 shows an overhead valve diesel engine equipped with a partially liquid-cooled forced air cooling device according to an embodiment of the present invention.
(A) is a longitudinal sectional front view of the main part of the engine, and (B) is a diagram
FIG. 6A is a cross-sectional plan view taken along the line V-V of the engine of FIG. 4A, and FIG. 6C is a vertical cross-sectional view of another embodiment of the cylinder baffle plate 20.

2 is a perspective view of the overhead valve diesel engine of FIG. 1. FIG.

FIG. 3 shows a prior invention example, and FIG. 3A is a vertical cross-sectional view of the main part,
(B) is a perspective view of the main part.

FIG. 4 is a view corresponding to FIG. 1A according to a conventional example.

FIG. 5 is a view corresponding to FIG. 1B according to a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Engine main body, 2 ... Cylinder head, 4 ... Cylinder, 4a ... Heat dissipation cylinder fin, 5 ... Sub combustion chamber, 1
0 ... Partial liquid cooling forced air cooling device, 11 ... Flywheel fan, 12 ... Flywheel part, 14 ... Fan case, 14a ... One side of case, 16 ... Radiator (oil cooler), 18 ... Liquid cooling chamber ( Oil cooling room),
20 ... Sirin air guide plate, 20a ... Plate start end side part, 20b ... Plate middle part, 20c ... Plate end side part, A ... Cooling air.

Claims (1)

[Scope of utility model registration request] 1. A centrifugal flywheel fan (11) and a fan case (14) are provided on the front side of the engine body (1), and a radiator (16) is provided on the upper front side of the cylinder head (2). The cooling air (A) generated by the flywheel fan (11) is guided by the fan case (14) to be divided into the cylinder (4), the cylinder head (2), and the radiator (16). A liquid cooling chamber (18) is formed on the outer periphery of the auxiliary combustion chamber (5) formed in the cylinder head (2), and the auxiliary combustion chamber (5) has a flywheel fan (11) for cooling air (A). ) Is located on the opposite side to the side where the liquid is blown up, and the liquid cooling chamber (18) and the radiator (16) are connected to each other so that the cooling liquid circulates. Of the inner space of the fan case (14), the cylinder
A cylinder baffle plate (20) is provided on the front side of (4) above the flywheel fan (11), and the plate start end side portion (20a) of the cylinder baffle plate (20) is a flywheel fan ( 11) extends toward one side (14a) of the case on the side where the cooling air (A) is blown up, and is positioned above the flywheel fan (11), and the plate intermediate portion (20b) is the fly Wheel fan (11)
Is located above the front surface of the flywheel portion (12) of the plate, and its plate end portion (20c) extends toward the case side other side portion (14b) on the side opposite to the side where the cooling air (A) is blown up, and the
A partly liquid-cooled forced air cooling system for an engine, characterized in that (A) is configured to guide air to the lateral and other side surfaces of the cylinder (4) on the side of the auxiliary combustion chamber (5).