AUTOMOTIVE RADIATOR

Abstract: A radiator for an automotive engine has a filler neck (16) having a coolant pass (117) therein. The filler neck has both an inner tubular member (101) and an outer tubular member (103) so that the coolant pass (117) is formed between the inner surface of the outer tubular member (103) and the outer surface of the inner tubular member (101). The coolant pass (117) is connected with a connecting pipe in order to introduce the coolant within the coolant pass (117) toward the connecting pipe. The coolant introduced into the connecting pipe then flows toward a reserve tank. Since all coolant flowing toward the connecting pipe is orientated its vector while passing through the coolant pass (117), the coolant can be introduced into the connecting pipe smoothly.

Description: The invention relates to an automotive radiator according to the preamble of claim 1. FR-A-2 411 306 discloses such an automotive radiator having an outer tubular member and an inner tubular member around a filler neck. A radiator cap is screwed on the inner tubular member by means of a screw. A channel is formed across the screw in axial direction of the tubular member, so that steam overflowing from the upper tank can flow into the connecting pipe. Japanese patent laid-open publication (KOKAI) 55-41391 discloses an automotive radiator comprising a tubular member which is connected to a filler neck formed on an upper tank and a radiator cap which has both negative pressure valve and a pressure valve connected to the tubular member as well as a connecting pipe connected with the tubular member so that the tubular member is connected with a reserve tank through the connecting pipe. The pressure valve of the radiator cap opens in order to release superheated steam within the upper tank to the reserve tank when the pressure within the upper tank increases up to the predetermined pressure. Such an automotive radiator as described above has a technical disadvantage. Namely, the superheated steam within the upper tank floods out from an annular sealing portion of the pressure valve in all directions when the pressure valve is opened. The stream of superheated steam, therefore, must be a whirling flow having all vectors. Since the connecting pipe is open at only one point of the side wall of the tubular member, it must be very difficult for such a whirling superheated steam flow to be introduced in the connecting pipe and to flow toward the reserve tank. The steam flow is retained within the tubular member so that the pressure within the tubular member increases and that influences the predetermined opening pressure of the pressure valve seriously. The object of the present invention is to avoid the above described technical disadvantages and to release the superheated steam within an upper tank to a reserve tank through a connecting pipe smoothly when the pressure valve opens the filler neck. This object is achieved by the features in the characterizing part of claim 1. The superheated steam flooded from the pressure valve is directed by flowing within the coolant pass so that the steam can be introduced into the connecting pipe after the flow vectors are oriented. Since the superheated steam flow flooded from the pressure valve is controlled in its vectors by the coolant pass in order to orient the flow toward the connecting pipe, the superheated steam can be introduced smoothly to the reserve tank. So the superheated steam can be released toward the reserve tank without increasing the pressure within both the inner tubular member and the outer tubular member so that the predetermined opening pressure of the pressure valve can be maintained. Fig. 1 is a sectional view showing an embodiment of the present invention and showing the section taken line I - I of Fig. 5, Fig. 2 is a sectional view showing the same structure shown in Fig. 1 but without cap, Fig. 3 is a sectional view taken along line III - III of Fig. 1 , Fig. 4 is a sectional view taken along line IV - IV of Fig. 3, Fig. 5 is a front view showing an automotive radiator provided with the embodiment of the present invention, Fig. 6 is a sectional view showing another embodiment taken along line VI - VI of Fig. 10, Fig. 7 is a sectional view showing the same structure as Fig. 6 but without cap, Fig. 8 is a sectional view taken along line VIII - VIII of Fig. 6, Fig. 9 is a sectional view taken along line IX - IX of Fig. 8, and Fig . 10 is a front view showing an automotive radiator. Fig. 5 is a front view showing an automotive radiator 500. An inlet port 14, through which an engine coolant heated within an automotive engine is introduced, is provided at an upper tank 10 which is made of resin. The inlet port 14 has a predetermined inner diameter in order be to connected with a pipe through which the coolant from the engine flows. The upper tank 10 has a filler neck 16 at an upper side thereof, and a cap 200 is detouchably connected with the filler neck 16. The upper tank 10 also has brackets 18 at an upper and side corner thereof. The automotive radiator 500 is fixed with an automotive body via the brackets 18. One end of a plurality of tubes 30 is connected with the upper tank 10 and the other end of the tubes 30 is connected with a lower tank which is made of reisn. Corrugated fins 32 are provided between the tubes 30. The lower tank 20 has an outlet port through which the coolant within the lower tank 20 flows toward the engine. Numerals 41 and 42 show caulking plates. An inner tubular member is connected with the filler neck 16 and are outer tubular member is connected with the inner tubular member. The cap 200 is detouchably fitted with the outer tubular member. The connecting pipe 111 is connected with the outer tubular member. The structure around the filler neck is described hereinafter. Fig. 1 is a sectional view taken along line I-I of Fig. 5, Fig. 2 is a sectional view showing the same structure shown in Fig. 1 but the cap 200 is omitted. The opening edge 11 of the upper tank 10 is inserted within a groove formed in a core plate 43 via an O-ring. The caulking plate 41 is beut in such a manner that the caulking plate 41 wraps both the core plate 43 and the opening edge 11 so that the upper tank 10 and the core plate 43 are connected. A plurality of tubes 30 are connected with the core plate 43 by welding. The inner tubular member 101 connected to the filler neck 16 extends upwardly so that the uppermost edge of the inner tubular member 101 forms an inner seal portion 105. One edge of the outer tubular member 103 is connected with the outer wall surface of the inner tubular member 101 at an inter-mediate portion of the inner tubular member 101. The outer tubular member 103 also extends upwardly so that the uppermost edge of the outer tubular member 103 forms an outer seal portion 107. A flange 109 to which an outer cap member 201 of the cap 200 is hooked is formed on the uppermost edge of the outer tubular member 103. The inner diameter of the outer tubular member 103 is larger than the outer diameter of the inner tubular member 101 by a predetermined amount. According to the preferred embodiment, the inner diameter of the outer tubular member 103 is 31 mm and the outer diameter of the inner tubular member 101 is 24 mm, so that an annular coolant pass 117 the width of which is 3.5 mm is formed between the outer wall surface of the inner tubular member 101 and the inner wall surface of the outer tubular member 103. The outer seal portion 107 of the outer tubular member 103 is located above the inner seal portion 105 of the inner tubular member 101. The connecting pipe 111 is connected with the outer tubular member 103 so that the annular coolant pass 111 is connected with the reserve tank through the connecting pipe 111. According to the preferred embodiment, the uppermost edge of the connecting pipe 111 is located almost in same position as the inner seal portion 105 and the lowermost edge of the connecting pipe 111 is located slightly above the bottom of the annular coolant pass 117. The cap 200 has a sealing member 205 which is inserted between the outer cap member 201 and an inner cap member 203. The sealing member 205 rests on the outer seal portion 107 for sealing the outer seal portion 107 when the outer cap member 201 is connected with the flange portion 109. The cap 200 is provided with a pressure valve 207 which has a sealing member 209 for sealing the inner seal portion 105. The sealing member 209 is biased toward the inner seal portion 105 by a spring which is provided between the pressure valve 207 and the inner cap member 203. A negative pressure valve 211 is provided within the pressure valve 207, and the negative pressure valve 211 also has a sealing member 213. Though in the position shown in Fig. 1 the sealing member 213 of the negative pressure valve 211 rests on the pressure valve 207, the sealing member 213 is detouched from the pressure valve 207 for connecting the atmosphere with the upper tank 10 via the space formed on the upper side of the pressure valve 207 when the pressure within the upper tank 10 is reduced below air pressure. Fig. 3 is a sectional view taken along the line III - III of Fig. 1. As shown in this Fig. 3, one end of the connecting pipe 111 opens to the annular coolant pass 117, and the connecting pipe 111 extends along the longitudinal axis of the upper tank 10. Since the inner diameter of the inlet port 14 is larger than the hight of the upper tank 10, an air leak pass 115 is formed between the upper portion of the inlet port 14 and the inner tubular member 101 so that the air retained at the upper portion of the inlet port 14 can escape to the inner tubular member 101. The sectional shape of the air leak pass 115 is semicircular, and the air leak pass 115 is formed at an upper portion of the upper tank 10 in such a manner that the air leak pass 115 opens to the inner portion of the upper tank 10. A supporting member 113 is formed between the connecting pipe 111 and the upper tank 10 and the supporting member extends from one edge of the connecting pipe 111 to an intermediate portion of the connecting pipe 111. Fig. 4 is a sectional view taken along line IV - IV of Fig. 3. As clearly shown by this Fig. 4, the annular coolant pass 117 is formed between the inner tubular member 101 and the outer tubular member 103. The connecting pipe 111 opens to the annular coolant pass 117. The air leak pass 115 is formed at the opposite side of the connecting pipe 111. The annular coolant pass 117 is substantially "C" shaped. The sealing member 209 of the pressure valve is lifted from the inner seal portion 105 against the biasing force of the spring 215 when the pressure in the upper tank 10 is increased up to the predetermined pressure valve, so that the superheated steam within the upper tank 10 flows toward the annular coolant pass 117 between the inner seal portion 105 and seal member 209. Since almost all the superheated steam flows toward the annular coolant pass 117, the flow of the superheated steam is oriented toward the annular coolant pass 117. All the superheated steam flows toward the annular coolant pass 117 and then flows along the pass 117 as shown by arrow F in Fig. 4 toward the connecting pipe 111. The superheated steam introduced into the connecting pipe 111 then flows toward the reserve tank. It should be noted that since all the superheated steam flows along the annular coolant pass 117, the flow of the superheated steam is oriented toward the connecting pipe 111 so that the superheated steam can be introduced smoothly into the connecting pipe 111. The sealing member 213 of the negative pressure valve opens a pass 217 formed in the pressure valve 207 so that the inner space of the upper tank 10 is connected with the space above the pressure valve 207 through the pass 217 when the pressure within the upper tank 10 decreases below air pressure. Therefore, the coolant within the reserve tank returns toward the upper tank 10 through the connecting pipe 111 and the pass 217. The air which is retained in the upper portion of the inlet port 14 and is introduced when the coolant is poured in the filler neck 16, escapes into the inner tubular member 101 through the air leak pass 115. The outer tubular member 103 of the second embodiment is connected to the inner tubular member 101 near the upper end portion of the inner tubular member 101 as shown in Fig. 6, and the coolant pass 117 formed between the outer wall surface of the inner tubular member 101 and the wall of the outer tubular member 103 is provided only around the opening portion of the connecting pipe 111, as shown in Figs. 7 - 10. The superheated steam within the upper tank 10 flows toward the coolant pass 117 through the inner seal portion 105 when the pressure valve 207 opens, so that the flow of the superheated steam is also oriented toward the coolant pass 117. Therefore the superheated steam can flow smoothly toward the reserve tank. Other portions of the second embodiment are the same as those of the first embodiment, and the elements of the second embodiment are, therefore, numbered with the same numerals as in the first embodiment.

Claims: An automotive radiator comprising an upper tank (10) to which coolant from an automotive engine flows, a filler neck (16) provided at said upper tank (10) and opening upwardly, a tubular member provided around said filler neck (16), said tubular member having an inner tubular member (101) one end of which is connected with said filler neck (16) and the other end of which opens upwardly for forming an inner seal portion (105) and an outer tubular member (103) one end of which is connected with an outer side wall of said inner tubular member (101) and the other end of which opens upwardly for forming an outer seal portion (107), a coolant pass (117) formed between the outer wall surface of said inner tubular member (101) and an inner wall surface of said outer tubular member (103) so that said coolant pass (117) is formed around said inner tubular member (101), a connecting pipe (111) one end of which is connected with said coolant pass (117) at a portion which is lower than a portion of said inner seal portion (105), and a cap (200) being detouchable and having a pressure valve (207) sitting on said inner seal portion (105) and opening said inner seal portion when the pressure within the upper tank increases up to a predetermined pressure, characterized in that the inner seal portion (105) is provided below the outer seal portion (107), and the cap (200) is detouchably connected with the outer tubular member (103), wherein a lower tank (20) is connected via tubes (30) with the upper tank (10), and wherein the other end of the connecting pipe (111) is connected with a reserve tank for the coolant. An automotive radiator according to claim 1, wherein said cap (200) has a negative pressure valve (207) which connects an inner side of said upper tank (10) with the connecting pipe (111), when a pressure within said upper tank decreases below predetermined pressure. An automotive radiator according to claim 1, wherein said coolant pass (117) is formed only around the one end of the connecting pipe (111). An automotive radiator according to claim 1, wherein the upper tank (10) and the lower tank (20) are made of resin. An automotive radiator according to claims 1 and 2, wherein said cap (200) has a spring (215) which biases said pressure valve (207) toward said inner seal portion (105), said spring being in contact with said pressure valve (207) at a portion lower than a portion of said inner seal portion (105).

Inventors: FUKUDA, SUNAO, KATO, SEIICHI, MUTO, SATOMI, NAGARA, TOSHIO, SUSA, SUMIO
Applicants: NIPPONDENSO CO., LTD.
Application year: 1987
Main classification: B65D51
IPC codes: F01P11, B60K11