JPH1054238A - Water-cooling device for engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To heighten scavenging efficiency of residual exhaust gas in a combustion chamber by fixing a flange part of an exhaust pipe in the state of being seated on a peripheral wall part of an exhaust part outlet provided at a head front face of a cylinder head, and fixing a peripheral wall part of a water pump outlet in the state of being seated on a peripheral wall part of a water jacket. SOLUTION: An intake pipe 13 is fitted to a head rear face 10a of a cylinder 10, and an exhaust port outlet 11a is opened in a head front face 10b. A flange part 14a of an exhaust pipe 14 is seated on a peripheral wall part of the outlet 11a and fixed. A water pump outlet 4c is opened in a lead-out end part of a discharge passage led out of a pump chamber of a water pump, and a water jacket inlet 8a is opened in the head front face 10b. A peripheral wall part of the water pump outlet 4c is seated on a peripheral wall part of the inlet 8a and fixed. The pump chamber can therefore be arranged in a position not interfereing with the exhaust pipe 14, and scavenging of residual exhaust gas is smoothed. A pump rear wall 4a is formed integrally with the flange part 14a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a water cooling device for an engine.

[0002]

2. Description of the Related Art FIGS. 5 and 6 show a prior art of a water cooling system for an engine. This is similar to the present invention.
It has the following basic structure. That is, as shown in FIG. 5, the flywheel 102 and the pump output wheel 103 are arranged in front of the crankcase 101 when the direction of the axis line 120a of the crankshaft 120 is regarded as the front-rear direction. A pump input wheel 105 is provided in front of 104e.
And the pump output wheel 103 and the pump input wheel 105
The endless flexible body 106 is wound around the water pump 104, and the water pump 104 is operated to circulate the cooling water between the water jacket 108 (see FIG. 6) of the engine and the radiator 107.

In this prior art, as shown in FIG. 5, a large flywheel 102 is provided on the front side of a crankcase 101.
Is located, there is no space for disposing the water pump 104 in front of the crankcase 101, and the pump chamber 10
4e, a water pump outlet 104c is provided on the rear surface, and a water jacket inlet 108a is provided on the head front surface 110b.
The water pump 104 is fixed to the front surface 110b of the head by seating and fixing the peripheral portion of the water pump outlet 104c to the peripheral portion of the water jacket inlet 108a. In order to avoid interference with the pump chamber 104e, the intake pipe 113 is provided on the rear face 110a of the head.
4 are attached to the head upper surface 110c, respectively. Reference numeral 108a in FIG.
7 is a water jacket 1 in the cylinder head 110
A communication port 123 for the cooling water from 08 to the water jacket 108 in the cylinder block 118 indicates the flow of the cooling water.

[0004]

The above prior art has the following problems. Generally, at the time of valve overlap near the end of the exhaust process, as shown in FIG. 6, the intake air 115 that has begun to be introduced from the intake pipe 113 into the combustion chamber 112 via the intake port 109.
Thereby, the residual exhaust gas 116 is scavenged from the combustion chamber 112 to the exhaust pipe 114 via the exhaust port 111. In this prior art, the intake pipe 113 is attached to the head rear face 110a and the exhaust pipe 114 is attached to the head upper face 110c, so that the introduction direction of the intake air 115 from the intake pipe 113 to the combustion chamber 112 is forward. The direction in which the residual exhaust gas 116 is led out from the combustion chamber 112 to the exhaust pipe 114 is upward. For this reason, the residual exhaust gas 116 is not smoothly pushed out to the exhaust pipe 114 side, and the scavenging efficiency is low. Therefore, the intake / exhaust efficiency is low, and the output performance tends to be low.

Since there is no means for cooling the exhaust gas passing through the exhaust pipe 114, the exhaust gas temperature is high and the expansion noise of the exhaust gas discharged into the atmosphere is large.

Since there is no means for reinforcing the fixed state of the water pump 104, the posture of the water pump 104 and, consequently, the posture of the pump input wheel 105 are disturbed by the tension of the endless flexible body 106, and the endless flexible body 106 comes off. There is.

The first invention has the following problems. Improving the scavenging efficiency of residual exhaust gas in the combustion chamber. To cool the exhaust passing through the exhaust pipe. Secure the water pump. The second invention has the following problems in addition to the problems of the first invention. To facilitate the processing of screw holes for mounting tension devices.

[0008]

[Means for Solving the Problems]

(First Invention) As shown in FIG. 1 or FIG. 2, the first invention is based on the assumption that the direction of the axis 20a of the crankshaft 20 is the front-rear direction, and that the flywheel 2 and the pump output wheel 3 are located on the front side of the crankcase 1. The pump input wheel 5 is disposed in front of the pump chamber 4 e of the water pump 4, and the endless flexible body 6 is wound around the pump output wheel 3 and the pump input wheel 5. A water cooling system for an engine in which cooling water is circulated between a water jacket 8 (see FIG. 3 or FIG. 4) of the engine and the radiator 7 is characterized as follows.

That is, as shown in FIG. 1, an intake pipe 13 is attached to a head rear surface 10a of a cylinder head 10,
As shown in FIG. 2, an exhaust port outlet 11a is opened in the front surface 10b of the head, and an exhaust pipe flange portion 14a of an exhaust pipe 14 is seated and fixed on a peripheral portion of the exhaust port outlet 11a. 4e, a discharge passage 4h is led out, and as shown in FIG. 4, a water pump outlet 4c is provided at a leading end of the discharge passage 4h, a water jacket inlet 8a is provided at a head front face 10b, and a periphery of the water jacket inlet 8a is provided. By seating and fixing the peripheral portion of the water pump outlet 4c to the meat portion, as shown in FIG. 2, the pump chamber 4e is arranged at a position where it does not interfere with the exhaust pipe 14, and as shown in FIG. The pump rear wall 4a faces the chamber 4e and the discharge passage 4h, and as shown in FIG. 3, the pump rear wall 4a is integrated with the exhaust pipe flange portion 14a.

(Second Invention) In a second invention, as shown in FIG. 3, in the first invention, a screw hole 25 is formed in a pump front cover 4b mounted on a pump rear wall 4a, and the screw hole 25 is fitted into the screw hole 25. It is characterized in that the tension device 24 of the endless flexible body 6 is attached to the front cover 4b of the pump with the attached mounting bolts 26.

[0011]

Actions and effects of the present invention

(First Invention) The first invention has the following effects (FIG. 3,
(See FIG. 4). Generally, at the time of valve overlap near the end of the exhaust process, the residual exhaust gas 16 flows from the combustion chamber 12 to the exhaust pipe 14 via the exhaust port 11 due to the intake air 15 which has been introduced into the combustion chamber 12 via the intake pipe 13 via the intake port 9. Is scavenged. In the present invention, the intake pipe 13 is provided on the rear surface 10a of the head.
Since the exhaust pipe 14 is attached to the front surface 10b of the head, the direction of introduction of the intake air 15 from the intake pipe 13 to the combustion chamber 12 is forward, and the direction of discharge of the residual exhaust gas 16 from the combustion chamber 12 to the exhaust pipe 14 is also forward. Becomes For this reason, the residual exhaust gas 16 is smoothly pushed out to the exhaust pipe 14 side by the intake air 15, and scavenging efficiency is high. Therefore, the intake / exhaust efficiency is high and the output performance is high.

The heat of the exhaust gas passing through the exhaust pipe 14 is radiated from the rear wall 4a of the pump to the cooling water passing through the pump chamber 4e and the discharge passage 4h through the exhaust pipe flange portion 14a. And the expansion noise of exhaust gas discharged into the atmosphere is reduced.

Since the water pump 4 is supported by seating and fixing both the exhaust pipe flange portion 14a and the peripheral portion of the water pump outlet 4c on the front surface 10b of the head, the attitude of the water pump 4 and hence the pump The attitude of the input wheel 5 is hard to be out of order, and the endless flexible body 6 is unlikely to be dislocated.

Since the screw hole 25 may be formed in the small and lightweight pump front cover 4b, the work can be fixed more securely than when the screw hole 25 is formed in the large and heavy cylinder head 10 or the cylinder block 18. It becomes easier and the processing work becomes easier.

[0015]

Embodiments of the present invention will be described with reference to the drawings. 1 to 4 are diagrams illustrating an engine according to an embodiment of the present invention. In this embodiment, a horizontal water-cooled diesel engine is used, and the configuration is as follows. As shown in FIG. 1 and FIG.
The cylinder head 10 is assembled to the cylinder block 18 having the above, and the head cover 19 is assembled to the cylinder head 10.

The structure of the water cooling system for this engine is as follows. That is, as shown in FIGS. 1 and 2, when viewed in a direction parallel to the direction of the axis 20 a of the crankshaft 20, the flywheel 2 and the pump output wheel 3 are arranged in front of the crankcase 1, and the water pump 4, a pump input wheel 5 is disposed in front of a pump chamber 4e, an endless flexible body 6 is wound around the pump output wheel 3 and the pump input wheel 5, and a water jacket 8 (see FIG. 3 or FIG. 4) and the radiator 7 to circulate the cooling water. As shown in FIG. 4, a pump front cover 4b is mounted on the front side of the pump rear wall 4a, and an impeller 4f is accommodated in a pump chamber 4e formed in the pump front cover 4b. Pump input wheel 5
Connected to. The pump chamber 4e is provided with a water pump inlet 4d.

As shown in FIG. 1, the flywheel 2 and the pump output shaft 3 are fixed to a crankshaft 20. FIG.
As shown in FIG. 2, the water jacket 8 is formed continuously over the inside of the cylinder head 10 and the inside of the cylinder block 18. 3 and 4, reference numeral 17 denotes a communication port for cooling water from the water jacket 8 in the cylinder head 10 to the water jacket 8 in the cylinder block 18, and reference numeral 23 denotes a flow of the cooling water. As shown in FIG. 1, a hot water pipe 21 is provided between the cylinder block 18 and the radiator 7, and a cold water pipe 22 is provided between the radiator 7 and the water pump 4. The water pump 4 is attached to the cylinder head 10. The cooling water in the cylinder block 18 circulates in the radiator 7, the water pump 4, and the cylinder head 10 in this order.

In this embodiment, as shown in FIG. 1, an intake pipe 13 is attached to a head rear surface 10a of a cylinder head 10, an exhaust port outlet 11a is opened in a head front surface 10b, and a peripheral portion of the exhaust port outlet 11a is formed. The exhaust pipe flange portion 14a of the exhaust pipe 14 is seated and fixed, and as shown in FIG. 2, the discharge passage 4h is led out from the pump chamber 4e of the water pump, and as shown in FIG. 4, the discharge passage 4h is led out. The water pump outlet 4c is provided at the end, the water jacket inlet 8a is provided at the head front face 10b, and the water pump outlet 4c is seated and fixed to the water jacket inlet 8a. As shown in FIG. 4, the pump chamber 4e is disposed at a position where it does not interfere with the exhaust pipe 14, and as shown in FIG. 4, the pump rear wall 4a faces the pump chamber 4e and the discharge passage 4h. So, as shown in FIG. 3, it is the pump back wall 4a is integrated with the exhaust pipe flange 14a. Water jacket inlet 8a is exhaust port outlet 1
a.

In this embodiment, a screw hole 25 is formed in the front cover 4b of the pump mounted on the rear wall 4a of the pump, and the endless flexible member 6 is screwed into the screw hole 25 with a mounting bolt 26.
Is mounted on the front cover 4b of the pump.

[Brief description of the drawings]

FIG. 1 is a plan view of an engine according to an embodiment of the present invention.

FIG. 2 is a front view of a main part of the engine of FIG.

FIG. 3 is a sectional view taken along line III-III of FIG. 2;

FIG. 4 is a sectional view taken along line IV-IV of FIG. 2;

FIG. 5 is a plan view of an engine according to the related art.

6 is a sectional view taken along line VI-VI of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Crankcase, 2 ... Flywheel, 3 ... Pump output wheel, 4 ... Water pump, 4a ... Pump rear wall, 4b ... Pump front cover, 4c ... Water pump outlet, 4e ... Pump room, 4
h: discharge passage, 5: pump input wheel, 6: endless flexible body, 7
... radiator, 8 ... water jacket, 8a ... water jacket inlet, 10 ... cylinder head, 10a
... Head rear surface, 10b Head front surface, 11a Exhaust port outlet, 13 ... Intake pipe, 14 ... Exhaust pipe, 14a ... Exhaust pipe flange, 20 ... Crank shaft, 20a ... Axis line, 24 ...
Tension device, 25: screw hole, 26: mounting bolt.

Claims (2)

[Claims] 1. A flywheel (2) and a pump output wheel (3) are arranged on the front side of a crankcase (1) when the direction of an axis (20a) of a crankshaft (20) is viewed as a front-rear direction. Water pump
A pump input wheel (5) is arranged in front of the pump chamber (4e) of (4), and an endless flexible body (6) is wound around the pump output wheel (3) and the pump input wheel (5). In a water cooling system for an engine, wherein a cooling water is circulated between a water jacket (8) of the engine and a radiator (7) by operation of a pump (4), a rear surface (10a) of a cylinder head (10) is provided. To intake pipe
(13) is attached, an exhaust port outlet (11a) is opened in the front surface (10b) of the head, and an exhaust pipe flange portion (14a) of the exhaust pipe (14) is seated on a peripheral portion of the exhaust port outlet (11a). After fixing, the discharge passage (4h) is led out from the pump chamber (4e) of the water pump (4), a water pump outlet (4c) is opened at the leading end of the discharge passage (4h), and the head front surface (10b) is opened. A water jacket inlet (8a) is opened, and a peripheral portion of a water pump outlet (4c) is seated and fixed on a peripheral portion of the water jacket inlet (8a), so that the pump chamber (4e) is connected to the exhaust pipe (14). ) And the pump room (4)
e) and the rear wall of the pump (4a) facing the inside of the discharge passage (4h), and this rear wall of the pump (4a) is connected to the exhaust pipe flange (14a).
A water cooling system for an engine, which is integrated with the engine. 2. A pump front cover mounted on a rear wall (4a) of the pump according to claim 1, wherein
A screw hole (25) is made in (4b), and the tension device (24) of the endless flexible body (6) is attached to the front cover (4b) of the endless flexible body (6) by a mounting bolt (26) screwed into the screw hole (25). Attached to
A water cooling device for an engine, comprising: