JPS61145313A - Cooling structure for ignition coil - Google Patents

Abstract

PURPOSE:To make it possible to surely cool an ignition coil body, by feeding cooling water from a radiator into through-holes formed in a housing storing therein the ignition coil body, through tubes. CONSTITUTION:Metal pipes 70 are disposed in through holes in a housing 1 storing therein an ignition coil body composed of a primary coil 9, a secondary coil 13 and an iron core 7. The inlets 70 of the pipes 70 are connected to tubes 80 while the outlets 72 of the same are connected commonly to a heater return pipe 85 from an engine block. Further, cooling water which has been cooled through the radiator 84 is led to flow into an ignition coil 100 from a water pump 81 through the tubes 83.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an ignition coil for an internal combustion engine, and in particular to cooling an ignition coil for igniting a multi-cylinder internal combustion engine without using a distributor. .

[Conventional technology]

As shown in Japanese Unexamined Patent Publication No. 59-185877, the conventional method is to insert an ignition coil section and a spark plug section into the water passage to the cylinder and throat to cool the ignition plug section and the ignition coil section. There is.

[Problem that the invention seeks to solve]

However, in the conventional type mentioned above, the water passage leading to the cylinder and throat is used to cool the ignition coil, but the temperature of the water passage usually reaches about 120 degrees, and the cooling of the ignition coil is interrupted. It is impossible to completely replace the ignition coil and spark plug, and when replacing the ignition coil and spark plug,
The main problem is that it is necessary to drain all the water in the water passage to the cylinder and the throat, making it very time consuming to replace it.

[Means for solving problems]

An ignition coil body having a primary coil, a secondary coil, and an iron core, a housing for housing the ignition coil body, and a housing provided for passing cooling water from a radiator,
The present invention provides an ignition coil cooling structure including: a through hole having an inlet and an outlet; and a tube for sending cooling water of the radiator to the inlet of the through hole.

[For production]

Cooling water from the radiator is sent through a tube to the through hole of the ignition coil.

〔Example〕

The present invention will be described below with reference to embodiments shown in the drawings.

In the first embodiment shown in FIGS. 1 to 5, a 1-shaped iron core 7 is disposed within a coil case 1 of an ignition coil 100. As shown in FIG. A primary bobbin 6 is integrally formed on the outer periphery of the iron core 7, and a primary coil 9 is wound around the outer periphery of the primary bobbin 6. Further, a secondary bobbin 11 is arranged around the outer periphery of the primary coil 9 with a space therebetween, and a secondary coil 13 is wound around the outer periphery of the bobbin 11. A cylindrical metal pipe 70 having good thermal conductivity, such as aluminum, is disposed opposite the outer periphery of the secondary coil 13 at a distance. Further, this metallic pipe 70 is insert-molded within the case 1. Furthermore, both ends of the pipe 70 are constricted and protrude from the end surface of the coil case 1. One end is an inlet 71 of a pipe 70 into which cooling water is inserted, and the other end is an outlet 72. Furthermore, protrusions 71a and 72a for preventing the tube 83 from being pulled out are formed at both ends of the pipe 70, respectively. Then, resin 3 is placed inside case 1.
1, and the above member is made of resin 31 to form case 1.
Fixed inside. In addition, the first to fourth plug caps 32, 22, 23, 33 connected to the secondary coil 13
are arranged at approximately equal intervals in a straight line. and,
Reference numeral 10 denotes a lead wire for sending a signal for controlling energization of the primary coil 90.

Here, the above-described ignition coil 100 is assembled into a four-cylinder double-over Radcam type engine 38 shown in FIG. This engine 38 has two camshafts 3 each having a cam pulley 40 mounted at one end at opposing positions.
9 are arranged, and the first camshaft 39 accommodates the camshaft 39.
．． A rad cover 41.42 is arranged on the second cylinder.

And the first. Rad cover to the second cylinder - 41°42
A space 43 is formed therebetween, and a step 44 for holding the coil case 1 of the ignition coil 100 is provided. Furthermore, four spark plugs 45 are mounted on the bottom surface of the space 43 in a straight line at approximately equal intervals. Then, the third. 1st. Second and fourth plug caps 32.22.2
Insert 3.33. After fixing the ignition coil 100, a magnetic shield cover 50 for preventing leakage magnetic flux generated from the ignition coil 100 is attached to the first. It is fixed to the upper end surface of the rad covers 41 and 42 to the second cylinder with screws 51, etc., and covers the space 4.

Cooling water for the third day of the engine is circulated from the radiator 84 through a rubber hose to the engine block and the entire engine radiator using the water pump 81 as a driving source. This cools the engine. There are various bypass passages 82 at the outlet of the water pump 81, and engine cooling water also circulates around the surge tank and heater. Therefore,
The present invention provides a bypass passage 82 at the outlet of the water pump 81.
The ignition coil 10002 is arranged in the space 43 of the engine 38 with the addition of one tube 83 divided into 24 parts.
The cooling pipe 70 is inserted into the outer periphery of the inlet 71 of the cooling pipe 70 and connected. At this time, the tube 8 is
3 is more difficult to pull out than inlet 71. The tube 83 is passed through the hole 53 of the belt cover 52 placed in front of the engine 38. The belt cover 52 also covers the cam pulley 40 of the camshaft 39.
It houses a belt 56 that connects the crankshaft 54 and the crank pulley 55 of the crankshaft 54. The rotation of the crankshaft 54 is then transmitted to the camshaft 39 via the belt 56 to rotate the wheels. Further, the ventilation hole 53 of the belt cover 52 is formed at a position where the belt 56 does not pass through and at a position corresponding to the ignition coil 100 provided in the space 43 of the engine 38. Furthermore, the outlet 72 of the cooling pipe 7o of the ignition coil 100 is commonly connected to a return pipe 85 for a heater installed in the engine block.

Here, since the ignition coil OO is sealed in the space 43, the temperature is considerably higher than that in the engine room (<80" Ca degrees), and the thermal load on the ignition coil 1°O is extremely high. Therefore, the allowable temperature rise of the ignition coil is only slightly allowed.

Therefore, the engine cooling water cooled by the radiator 84 (7
(approximately 0° C.) flows into the ignition coil 100 by the water pump 81, cools the ignition coil 100, and then flows out to the engine block. Further, after circulating around the engine block and engine head, the engine cooling water (about 120° C.) returns to the radiator 84. That is, the engine cooling water (70
℃) around the ignition coil 100,
The ambient temperature of the ignition coil 100 can be kept low. Further, since the heat generated by driving the ignition coil 100 is absorbed by the engine cooling water, the temperature rise due to the heat generated by the ignition coil 100 can be suppressed to a low level. Further, the hole 53 sends air into the space 43 of the engine 38 and releases the heat in the space 43 to the outside. In this way, the thermal load can be reduced. This allows the ignition coil 100 to be made smaller and lighter.

In the second embodiment shown in FIGS. 6 and 7, the pipe 70 is formed in a U-shape and extends around the outer circumference of the coil. The cooling water discharged from the lower tank 84b (low temperature side) of the radiator 84 passes through the water pump 81 and enters the inlet 71 side of the pipe 70. Also, pipe 70
The cooling water coming out from the outleft 72 side of the radiator 8
No. 4 upper tank 84a (high temperature side).

In the embodiment described above, the ignition coil was used in a double-over-Radcam type engine 38, but it may be used in other types of engines.

In addition, each spark plug uses a high voltage diode,
Although power is distributed in the above example, power may be distributed using two double ignition coils.

Further, in the case of an eight-cylinder engine, two ignition coils 100 of the above-described embodiment may be used.

In addition, the outer periphery of the pipe 70 may be made into a bellows shape, or the outer periphery may be shaped like a bellows.
By attaching the fins, cooling performance can be increased and furthermore, the pipe 70 can be prevented from being pulled out from the resin 31.

Although the pipe 70 having a through hole is used to pass cooling water into the ignition coil 10, the through hole may be formed directly in the resin 31 by molding or casting without using the pipe 70. good.

Further, the through hole may be formed later by cutting or the like.

〔Effect of the invention〕

As described above, in the present invention, since the radiator cooling water is sent through the tube to the through hole provided in the housing that houses the ignition coil body, the ignition coil body can be reliably cooled by the radiator cooling water. can. Another advantage is that the ignition coil can be easily replaced using just a tube.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a first embodiment of the cooling structure for the ignition coil of the present invention, FIG. 2 is a longitudinal sectional view of the ignition coil shown in FIG. 1, and FIGS. 3 and 4 show the ignition coil. A plan view and a front view, FIG. 5 is a partially sectional side view showing the configuration of the main parts when the ignition coil is installed in an engine, and FIG. 6 is a perspective view showing a second embodiment of the cooling structure for the ignition coil of the present invention. , 7th
The figure is a plan view of the ignition coil shown in FIG. 6. 7... Iron core, 9... Primary coil, 13... Secondary coil, 31... Resin, 70... Pipe, 71...
Inlet, 72...Outlet, 83...Tube, 84...Radiator.

Claims (1)

[Claims] An ignition coil body having a primary coil, a secondary coil, and an iron core, a housing for housing the ignition coil body, and a housing provided for passing cooling water from a radiator,
An ignition coil cooling structure comprising: a through hole having an inlet and an outlet; and a tube for sending cooling water of the radiator to the inlet of the through hole.