JPH063141Y2 - Engine cooling water extraction structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a cooling water extraction structure in an engine having a member to be heated which is heated by cooling water of the engine.

(Prior Art) Due to demands for engine performance and the like, a DOHC engine in which two camshafts are arranged on a cylinder head for a cylinder row arranged in a row has been proposed and put into practical use. . Specifically, for example, there is an engine disclosed in Japanese Utility Model Laid-Open No. 60-82534.

On the other hand, an engine may have a heated member that is heated by using cooling water of the engine. For example, on the cylinder head or cylinder block of the engine,
There is a throttle valve which is provided with a communication passage for taking out cooling water which communicates between a space outside the engine and a cooling water passage inside the engine, and is heated by the cooling water taken out through this communication passage. This is to prevent the problem that the water in the intake air freezes in the throttle valve and hinders the movement of the throttle valve at the time of cold start.

(Problems to be solved by the invention) In an engine having such a member to be heated, a communication passage for taking out cooling water for supplying cooling water to the member to be heated is formed in a cylinder head or a block of the engine. Therefore, there is a problem that extra space is required for the cylinder head and the block, which may lead to an increase in size of the engine.

(Means for Solving the Problems) In the present invention, when a DOHC engine has a member to be heated, a dead water spacer for the cylinder head is provided as a communication passage for supplying cooling water to the member to be heated. It is intended to solve the above problem by using it. That is, the engine cooling water extraction structure according to the present invention has two spark plug mounting portions on the cylinder head of an engine with a double overhead camshaft.
In a DOHC engine provided with members to be heated that are arranged between the camshafts of the book in the axial direction of the camshafts and that are heated by engine cooling water, the ignition plug attachment is provided near the ignition plug attachment portion. A communication passage that communicates the cooling water passage near the portion with the space between the two camshafts, and a supply portion that is connected to the communication passage and that supplies the cooling water extracted from the communication passage to the heated member. It is characterized by comprising.

(Operation) In the engine having the above-described structure, the communication passage for cooling extraction is formed between the two camshafts, which are originally dead spaces, so that the dead spaces can be effectively used and the cylinder head can be effectively used. Does not increase in size.
In addition, the vicinity of the spark plug mounting part where this communication passage is provided is the place where the temperature becomes the highest due to the heat from the engine. Therefore, the cooling water taken out from this part is also the highest temperature and is not heated. Effective heating of the member is achieved.

(Embodiment) Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a plan view showing a V-type engine 1 having a cooling water extraction structure according to the present invention as viewed from above. In this engine, a cylinder block is formed in a V shape, and a pair of cylinder heads 2 and 3 are provided on the top of the cylinder block. Each cylinder head 2 and 3 has a V inside a V-shaped cylinder block.
It is attached so as to cover the upper portion of a cylinder formed along the letter, and an intake / exhaust port is formed in each cylinder head and an ignition plug is arranged. This engine is a DOHC engine, and an intake / exhaust valve for opening / closing the intake / exhaust port is attached to each intake / exhaust port, and each cylinder head 2,
A pair of cam shafts 4a, 4b and 5a, 5b for activating the intake and exhaust valves are arranged on the upper side of the shaft 3 in the left-right direction in the figure. Head covers 6 and 7 are mounted on the cylinder heads 2 and 3 so as to cover the camshaft. Further, above the space between the cylinder heads 2 and 3, there are disposed intake manifolds 12 and 12 for supplying a fuel mixture into the cylinder chamber through the intake and exhaust ports, and a surge tank 11 connected to the intake manifolds 12 and 12. A throttle valve 14 is connected to the surge tank 11 via an intake passage 13.

The throttle valve 14 controls the amount of the air-fuel mixture sucked into the cylinder chamber, has an opening / closing valve, and controls the amount of the air-fuel mixture by operating the opening / closing valve.
When such a throttle valve 14 is used, in order to prevent water in the air from being frozen in cold weather to prevent smooth operation of the on-off valve, the throttle valve is controlled by the engine cooling water through the pipe 10. I am trying to make 14 heating. As described above, when the cooling water of the engine is taken out, the disposition of the communication passage that connects the cooling water passage inside the engine and the space outside the engine is likely to be a problem. It is provided on the head 2 and between the pair of cam shafts 5a, 5b, and thereby, the dead space is effectively used and the throttle valve 14 is effectively heated.

Regarding this point, FIG. 2 showing the cylinder head 3 provided with the communication passage for taking out the cooling water in the engine 1 with its head cover 7 and the camshafts 5a, 5b removed, and an arrow III in FIG. A description will be given based on FIG. 3 which is a cross-sectional view taken along line III.

As shown in FIG. 2, on the upper surface of the cylinder head 3, there are formed intake ports 31, 31 and exhaust ports 32, 32 penetrating up and down for intake and exhaust into the cylinder chamber. Therefore, these intake ports 31, 31 and exhaust port 3
Operate the intake and exhaust valves attached to 2, 32 2
The camshafts 5a, 5b of the book are arranged so as to extend to the left and right in the figure. The cylinder head 3 between the intake ports 31 and 31 and the exhaust ports 32 and 32 has an ignition plug mounting hole 33 that penetrates vertically. Although FIG. 2 shows only one cylinder, the other cylinders are arranged side by side in the left direction in FIG. 2, and therefore the ignition plug mounting holes of the other cylinders are also the above-mentioned mounting holes. 33. The spark plug mounting holes (and spark plug mounting portions) are formed side by side with respect to 33, and the spark plug mounting holes (and spark plug mounting portions) are aligned between the two cam shafts 5a, 5b and in the axial direction of the cam shafts 5a, 5b. Will be formed in.

The communication passage 34 for supplying the engine cooling water to the throttle valve 14 is formed between the two cam shafts and in the vicinity of the spark plug attachment portion formed side by side in the axial direction as described above. As is clear from FIG. 3, the communication passage 34 connects the engine cooling water passage 35 formed around the ignition plug mounting hole 33 and the space between the two camshafts. One end of the pipe 10 shown in FIG. 1 is connected to the space side end. The pipe 10 constitutes a supply passage in the present invention, and the cooling water in the cooling water passage 35 is supplied to the throttle valve 14 through the pipe 10 after passing through the communication passage 34. It should be noted that the engine cooling water is likely to have the highest temperature around the spark plug mounting hole 33, so that the cooling water taken out from the passage 35 in this portion is also the highest temperature, and therefore the heating of the throttle valve 14 is also effective. Done. An oil passage 36 is formed above the cooling water passage 35.

(Effect of the Invention) As described above, according to the present invention, the spark plug mounting portions are provided between the two camshafts on the cylinder head and side by side in the axial direction of the camshafts, and the engine to be heated is cooled by the member to be heated. In the vicinity of the spark plug attachment portion, a cooling water extraction communication passage to which a water supply passage is connected is provided in the vicinity of the spark plug attachment portion and
Since it is provided so as to communicate with the space between the two camshafts, the two camshafts, which are originally dead spaces, can be effectively used, and the cylinder head does not increase in size. , The vicinity of the spark plug attachment part where the cooling water extraction passage is provided is the place where the heat from the engine reaches the highest temperature. Therefore, the cooling water extracted from this part also reaches the highest temperature. Therefore, the heated member can be effectively heated.

[Brief description of drawings]

FIG. 1 is a plan view of a V-type engine having a cooling water take-out structure according to the present invention, FIG. 2 is a plan view showing one cylinder head of the engine, and FIG. It is sectional drawing shown along. 2, 3 ... Cylinder head 4a, 4b, 5a, 5b ... Camshaft 6, 7 ... Head cover, 10 ... Pipe 11 ... Surge tank, 12 ... Intake manifold 14 ... Throttle valve 34 ... Communication passage, 35 ... Cooling water passage

Claims (1)

[Scope of utility model registration request] 1. A spark plug mounting portion is provided on a cylinder head of an engine with a double overhead camshaft.
In a DOHC engine provided with members to be heated that are arranged between the camshafts of the book in the axial direction of the camshafts and that are heated by engine cooling water, the ignition plug attachment is provided near the ignition plug attachment portion. A communication passage that communicates a cooling water passage near the portion with the space between the two cam shafts, and a supply passage that is connected to the communication passage and supplies cooling water taken out from the communication passage to the heated member. A cooling water extraction structure for an engine, comprising: