JPS62103456A - Electromagnetic fuel injection valve - Google Patents

Abstract

PURPOSE:To prevent a fuel injection valve from being heated, by attaching a heat-radiating member formed of a highly heat-conductive cylindrical member on the outer periphery of the body of the fuel injection. CONSTITUTION:This fuel injection valve is used by energizing a solenoid coil 4, and at that time the coil 4 therefore generates heat due to its resistance. In order to radiate the heat, an aluminum heat radiating cover 100 formed of a highly heat-conductive cylindrical member is fitted on the outer periphery of a part where the solenoid coil 4 is disposed, being in close contact with the same. With this arrangement, it is possible to effectively prevent the fuel injection valve from being heated, and therefore, no faults such as, for example, vapor-lock, occur. Accordingly, it is possible to inhibit the high temperature characteristic of an internal combustion engine from lowering, and thereby the engine may be operated under a severe condition.

Description

[Detailed description of the invention]

(Industrial Application Field) A fuel injection valve is sometimes used as one of the means for supplying fuel to an internal combustion engine used in an automobile or the like. The present invention relates to an improvement in an electromagnetic fuel injection valve in which opening and closing adjustment of the valve is driven by an electromagnetic solenoid. (Prior art) Since the fuel injection valve is placed adjacent to the internal combustion engine, it is heated by the transfer of heat from the internal combustion engine.The temperature of the fuel injection valve rises and reaches a certain level. If the temperature exceeds the temperature, the fuel evaporates inside the fuel injection valve, causing the so-called paper rotter phenomenon, which impairs the fuel supply. As a result, the temperature characteristics of the internal combustion engine become low F. To avoid this, the fuel Insulating the injection valve to reduce heat transfer
An attempt has been made for each scale. These are Utsukai 56-
138151. ! 17-178164.58-7044
I5.58-29161 Publication No. A is shown. In addition, especially for internal combustion engines using alcohol, cooling water is circulated through the combustion nozzle 1 to prevent l'C heating. This is published in Japanese Utility Model Application Publication No. 57-35460! fl ;1\ has been done. (Problems that the invention solves) Previous t

[! The first method, ie, the method of covering the fuel injector with heat insulation, cannot be said to be an effective method in various situations where it is impossible to completely insulate the fuel injection valve. 1. : In a conventional electromagnetic fuel injection valve, a current of a predetermined value of 111 or more flows through the 1.1 magnetic solenoid, which causes the solenoid to generate resistance and prevent the film from melting. A resistor was inserted externally between the fuel injection valve and the fuel injection valve. However, in this method, the current is limited to the solenoid coil itself because the 1.1 resistance is the cause of the storage and it is troublesome to deal with the heat generated by the resistance. II'V IA
Various proposals have been made to strengthen the M River and remove external resistance. This technology is published in Japanese Unexamined Patent Application Publication No. 152-152-! +! 1020
, Utility Model Publication No. 59-2981.59-73571
and is shown. According to such a technique, the solenoid becomes a heating element, and even if the fuel injection valve is covered with a heat insulating material, it is not only useless, but also causes harm. Circulating cold 7JI water through the fuel injection valve is an effective method to prevent overheating, but requires small adjustments.
There remains a problem in terms of cost.The present invention aims to provide an electromagnetic fuel injection valve that is simple, inexpensive, and can effectively reduce heating. The above-mentioned problem is solved in the fuel r1 injection valve on the internal combustion engine side.
This is realized by an electromagnetic fuel injection valve which has a waste heat part (4) attached to the outer periphery of the fuel injection valve body. (Function) By installing the heat radiation part (4) as described above, , the heat transferred from the internal combustion engine and the heat generated inside the fuel injection valve is radiated from the heat dissipation member and prevents the fuel injection valve from heating.
-The reduction of the internal combustion engine's 6 thirst special case is it! HJ is done,
Also, it is possible to prevent the solenoid coil from melting (). (Example) At No. 1 in Figure 7, heat dissipation 8, which is the gist of the present invention, is shown.
1. Install the 1st part A. 3. The solenoid 4, together with the coil holder 16, is fixed between the fixed iron core 2 and the housing body 6 of the fuel injector. 4. The housing body 6 has magnetic permeability. high quality materials (aluminum,
It is made of silicon-containing steel, so-called Holo 1 stainless steel. 5. A jTl dynamic ridge core 14 is inserted between the fixed iron core 2 and the housing body 6. 6, a magnetic circuit is formed by the fixed iron core 2, the housing body 6, and the movable iron core 14. 7. The movable core 14 can move slightly in the axial direction. At all times, the spring 15 is biased toward the tip. When the solenoid is energized, a suction force is generated in the slight gap between the fixed iron core and the movable iron core, causing the movable iron core to move slightly to the right in the figure. 8. The movable iron core is connected to the valve support cylinder 13. 9. A flange 13a is provided on the outer periphery of the valve support cylinder 13, and the range of r1 capacity is limited by the collar 7. 10. A ball valve 11 is fixed to the tip of the valve support cylinder 13, and is in contact with the valve seat surface 10. 11. This fuel injection valve IG, L nozzle cover 9 is attached to the internal combustion engine side, and the other end is in contact with the valve seat surface 10. is connected to the fuel pump via the storage unit 17 (1). 12. The solenoid is energized and the movable core is connected to the fixed core side I.
J pull 1! When the ball valve 11 is
A gap is created between the valve seat surfaces 10. This unity is affected by fuel and internal combustion engines. 13, valve bore'-12I; slidably holds the L valve support 13, and A-ring 3.5. fl is sealed to prevent fuel +1 from leaking out. 14, Solenoid 1: is energized (31 is connected to the external connection terminal 18). This fuel injection valve T and L solenoids are energized and used, but when energized, the solenoid generates heat due to resistance.
Ru. The housing body is made of electromagnetic slanless material with high magnetic permeability (although this material has a metal material O'+1 grade).
C(,1Thermal conductivity is relatively low.Therefore, it is difficult for heat to escape, and -1Il is less likely to be heated.1.11C)
There is. 31.In order to prevent heat transfer from between the internal combustion layers, ¥117! 1J・1 valve is insulated (if it is not covered with A, the heat generated from the solenoid will be trapped in the fuel injection valve h'l'), and the word C using this 1st stage is (2). Invention e includes a heat dissipating member around the fuel injection valve to prevent the fuel injection valve from heating.Hereinafter, embodiments illustrated in FIGS. 1 to 6 will be described. First Embodiment In this embodiment, the aluminum 6 & Atagawa cover (100) shown in FIG. It is tightly inserted into the outer periphery.The fact that this aluminum cylinder performs a heat dissipation function can be understood from the following analysis and experimental results.The outer diameter of the solenoid coil is rl, and the outer diameter of the housing body is Let r2 be the outside diameter of the aluminum cylinder, r3 be the outer diameter of the aluminum cylinder, and let the calorific value of the solenoid coil be 11 Q force per 1 swell.Here, if we consider the middle position in the axial direction, Newton's law of cold 7Jl Therefore, when there is no cover, 0−2παr
2 (12°-1'a) (1) lI with cover = 'i
Q -2yr a r3 (Ta-Ta) (2
) holds true. I Kodashi α is the surface heat transfer coefficient, Ta is the outside temperature, ■2° is the surface mixture of the housing body when there is no cover, I' 31. L 7' is the surface temperature of the lumi paper. Next, the ablation inside the aluminum cylinder is determined assuming that one file is in a steady state. Half life is r, I rate is 3 for advance payment of aluminum.
16, the following differential equation holds true. (,)---2yr r k3 dl/dr
(3) Solve V-1 (-C1 Substitute the boundary ordinance obtained from equation (2) J r (r) = Ta + (1/(2yr U r3) 40/(
27r k3)*In(r3/r) (4) 81: 2111 at the boundary of the housing body and aluminum cylinder is (2=
Ta10/(2yr a r3) 10/(2π to 3
)*In(r3/r2) (5). -) Next, if we perform similar ML DI on the hot stone distribution inside the housing body and use equation (5) as the boundary condition, we get
1'(r)-Ta*Q/(2yr tx r3)+Q/
(3 in 2π)*1n(r3/r2)+Q/(2 in 2π)
*1n(r2/r) (6), where 2 is the thermal conductivity of the electromagnetic stainless steel, and from this, the surface temperature of the solenoid is T1=Ta*O/(2yr a r3)+
0/(3 in 2π)*In(r3/r2)+Q/(2 in 2π)*In(r2/rl) (7) Roar. 9 Using the boundary strip f1 of equation (1) with no cover on the first piece, 4 times the same piece 1n, T(r)=Ta+Q/(2π (Z r2)l/(2
yr k2)*1n(r2/r) (8),
Solenoid surface temperature 6.1 TI' -Ta+O/(:)πrx r2)+Q/(
2) In(r2/rl) (9) at 2π. Here, in order to compare the surface temperature of the solenoid with no cover and the surface temperature of the solenoid with the cover, subtract equation (7) from equation (9).
T1=Q/(2π)*((1/(αr2)+(In r
2)/to 3)-(1/(αr3)4(In r3)/to 3)) (10). Here, f (r) = (k3/α)*(1/r)+
In(r) (11), - As an example, 3 is the thermal conductivity of aluminum, and α is 10 km/hPi! Substituting the surface heat transfer coefficient when the wind speed of i hits the pipe, the value of k3/α becomes approximately 0.05. A graph obtained by substituting this value into equation (11) is shown in FIG. From this graph, the value of t (') has the lowest value when r is 0.05 (the median is meters), and in the range of 50111 or less, i, 1. As r' increases, the ratio of f (r) increases. It shows that τ decreases.Comparing this with equation (10), we get
11°-11=(1/(3 to 2π)*(1'ff2)-
f(r3)) (12) Do<C, fuel injection θ・1
When the radius of the valve is 50111 m or less, the mouth and aluminum cylinder produce a heat dissipation effect, and this effect is greater than the radius of the cover of 50 m.
The closer it is to mm, the larger it is. The fuel injection valve of the example has an outer diameter of approximately 21 mm, which fully satisfies this condition. The distribution analysis is shown in a glass form in FIG. In this figure, the curve 1 is the curve 1 without the cover.
This is a graph of equation (8), and the lower curve is a graph of the cover's condition, that is, equations <4> and (6). Here, ΔT1 is the difference in hot water temperature due to the cover increasing the surface area and lowering the C surface temperature, and ΔF2 is the difference in temperature when the cover is integrated.
There is a temperature difference of 1. It is immediately determined that the cover performs a heat dissipation function under the row fi in which ΔT1 is greater than ΔT2.1. h'l thermal effect is effective because ΔT2 is small compared to materials with high thermal conductivity. In addition to aluminum, copper, silver, etc. are also suitable. Next, the experimental results will be explained. The fuel injection valve used in this experiment has a housing body with an outer diameter of 21 mm, and aluminum cylinders of various outer diameters are inserted into this and tightly pressed to form a solenoid.
Continuous current was applied for 0 minutes, and the temperature at point M in Figure 1(b) was measured using a Reamister. The length of the cylinder (approximately 16 mm, as shown in Figure 1 ([)), is slightly longer than the solenoid.The aluminum cylinder is effective due to the t port.
Mf is recognized to be functioning as a ht heat shrine. Example 2 This is an aluminum cylinder (2 (10)
Three HL heating fins were placed around the circumference of the fin. The length of the cylinder is the same as the first example, and the outer diameter of the fin is 3.
When Qmm and the diameter without fins were set to 23 mm, the wetted surface decreased to 105°C. This t indicates that the heat dissipation effect is higher than that of the first embodiment. Embodiment 3 As shown in Fig. 3, there is an example in which eight heat dissipation fins extending in the axial direction are installed at equal intervals in the heat dissipation part +A (3 (10)).In this case, the outer diameter of the fins is The temperature decreased to 109°C, far from 30mm.
Heat dissipation effects such as IT can be obtained. Implementation pA/I As shown in FIG.
A greater heat dissipation effect than in the example can be obtained. Of course, it is also possible to use it in combination with fins as in the 2.3 embodiment. Embodiment 5 As shown in FIG. 5, this is an example e in which a heat radiation cylinder (500) is attached over almost the entire length of the fuel injection valve. In this case, heat generated from the solenoid is mainly radiated near the solenoid, and heat transmitted from the internal combustion engine is radiated at the tip of the fuel injection valve. Therefore, this type prevents the fuel injection valve from overheating in any of the following conditions: high-speed operating conditions where the solenoid generates a large amount of heat, low-speed operating conditions where the internal combustion engine becomes hot, or immediately after the engine has stopped operating! Two can be done. As shown in FIG. 6, the example of the embodiment is one in which a heat radiating member (600) is attached to the tip end side of the fuel injection valve, and the fuel injection valve is heated mainly by heat transferred from the internal combustion engine. Prevent this from happening. In the case of the fifth and sixth embodiments, it is also possible to combine the heat dissipation fins. (Effects) By appropriately attaching a heat radiation member to the fuel injection valve as described above, heating of the fuel injection valve can be effectively prevented. This prevents heating of the fuel and prevents problems such as vapor lock. Therefore, it is possible to stop the drop in the high-drainage characteristic of the internal combustion engine by 1!11 (.
It is possible to prevent melting of Ifψ of 1/I − −1 yl. + 1J2, 1; Can be used under harsh conditions f1 (7
The combustion angle injection 01 ji' has been realized (・The #6 construction is solid and durable'//1 song A11). 4. Simplification of drawings 11j /7. Figures 1 and 6 (a) show the first to sixth embodiments of the heat dissipation part installed on the fuel injection valve 1, and (b) shows the installation number of the heat dissipation part installed on the fuel injection valve 171. We accept a central sectional view of the flattened state. Figure 7 shows a central sectional view of an electromagnetic fuel injection valve before the heat radiation part was removed. FIG. 8 is a graph 1 (1) which is used to confirm that the heating action is taking place, and FIG. 0 is a graph showing the temperature distribution of the heat dissipation cover of the fuel injection valve.

Claims (6)

[Claims] (1) An electromagnetic fuel injection valve for internal combustion engines, in which a heat radiation member is attached to the outer periphery of the fuel injection valve body. (2) The electromagnetic fuel injection valve according to claim 1, wherein the heat radiation member is a cylindrical body with high thermal conductivity. (3) The electromagnetic fuel injection valve according to claim 1 or 2, wherein the heat radiation member has heat radiation fins with high thermal conductivity. (4) Any one of claims 1 to 3, characterized in that the heat radiation member is attached to the outer periphery of a position where a solenoid coil assembled into the main body of the fuel injection valve is present. The electromagnetic fuel injection valve described in the book. (5) The electromagnetic fuel injection valve according to any one of claims 1 to 3, wherein a heat radiation member is attached to the outer periphery of the front end side of the main body of the fuel injection valve. (6) The electromagnetic fuel injection valve according to any one of claims 1 to 3, characterized in that a heat radiation member is attached over almost the entire length of the main body of the fuel injection valve. .