JP2008150975A - Sub-chamber structure of fuel tank - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently supply fuel to a sub-chamber from the body of a fuel tank, without requiring a special driving source. <P>SOLUTION: Since two check valves 30F and 30R allowing the movement of the fuel to the inside from the outside of the sub-chamber 15 and checking the movement of the fuel to the outside from the inside are arranged in a side wall 15a lower part of the sub-chamber 15 arranged inside a tank body 11, the fuel introduced once into the sub-chamber 15 from the tank body 11 side is prevented from returning again to the tank body 11 side, and the fuel can be surely supplied by preventing a sucking-up filter 23 continuing with a fuel pump 21 from being exposed from a fuel liquid level even when the fuel liquid level is inclined. Moreover, since the two check valves 30F and 30R are arranged, the longitudinally-laterally moving fuel can be efficiently introduced into the sub-chamber 15 via any check valves 30F and 30R. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  According to the present invention, a fuel suction portion connected to a fuel pump is provided in a sub chamber arranged inside the tank body, and fuel is allowed to move from the outside to the inside of the sub chamber at a lower portion of the side wall of the sub chamber. The present invention relates to a sub-chamber structure of a fuel tank provided with a check valve for preventing movement of fuel from the inside to the outside.

  Such a sub-chamber structure of the fuel tank is known from Japanese Patent Application Laid-Open No. 2004-228561. The sub-chamber (swivel tank) described in Patent Document 1 has a suction port and a valve guide hole formed in the lower part of the side wall, and a check valve having a valve shaft slidably fitted in the valve guide hole. It is made to oppose the said suction inlet from the inner surface side of the side wall of a subchamber. When the fuel in the fuel tank moves with the acceleration / deceleration or turning of the vehicle, the check valve is pushed open and the fuel flows into the sub-chamber through the suction port. It is held inside the sub-chamber. Therefore, even if the fuel level inclines when the remaining amount of fuel in the fuel tank is reduced, the fuel level in the sub-chamber is secured and the fuel suction part connected to the fuel pump is located above the fuel level. It is possible to prevent the situation where the fuel supply becomes impossible due to exposure.

An in-tank type fuel pump is arranged inside the swirl tank (subchamber), a pressure regulator is provided in the middle of the feed pipe for sending fuel from the fuel pump, and the pressure regulator is branched and discharged. Patent Document 2 below discloses a jet pump that operates with surplus fuel and uses the jet pump to suck the fuel in the tank body into the sub-chamber.
Japanese Utility Model Publication No. 4-83920 JP 2005-155513 A

  However, since only one check valve is provided on the side wall of the sub-chamber in the above-mentioned Patent Document 1, the fuel is used only when the fuel in the fuel tank moves in the direction to open the check valve. Could not be introduced into the sub-chamber and the fuel liquid level in the sub-chamber could be lowered depending on the motion state of the vehicle.

  Moreover, since what was described in the said patent document 2 drives a jet pump using the surplus of the fuel which a fuel pump discharges, it is necessary to set the capacity | capacitance of a fuel pump large by the consumption of a jet pump, For this reason, there is a problem that the fuel pump becomes large and power consumption increases.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to efficiently supply fuel from a tank body of a fuel tank to a sub-chamber without requiring a special drive source.

  In order to achieve the above object, according to the first aspect of the present invention, a fuel suction portion connected to the fuel pump is provided inside the sub-chamber arranged inside the tank body, and the sub-chamber has a side wall under the side wall. In the sub-chamber structure of the fuel tank provided with a check valve that allows the fuel to move from the outside to the inside of the sub chamber and prevents the movement of the fuel from the inside to the outside, a plurality of the check valves are provided. A sub-chamber structure of a fuel tank is proposed.

  According to a second aspect of the present invention, in addition to the configuration of the first aspect, the plurality of check valves are arranged at substantially equal angular intervals centering on a central portion of the sub-chamber. A sub-chamber structure of the tank is proposed.

  According to the invention described in claim 3, in addition to the configuration of claim 2, the number of the check valves is two, and the line connecting the two check valves is in the vehicle longitudinal direction. A sub-chamber structure for a fuel tank is proposed which is inclined at an acute angle.

  The suction filter 23 according to the embodiment corresponds to the fuel suction portion of the present invention.

  According to the first aspect of the present invention, the fuel is allowed to move from the outside to the inside of the sub-chamber in the lower portion of the side wall of the sub-chamber arranged inside the tank main body, and the reverse of preventing the movement of the fuel from the inside to the outside. Since the stop valve is provided, the fuel once introduced from the tank main body side to the sub-chamber side does not return to the tank main body side again, and the fuel suction part connected to the fuel pump even when the fuel level is inclined due to acceleration / deceleration or turning It is possible to prevent fuel from being exposed from the fuel liquid level and enable reliable fuel supply. In addition, since a plurality of check valves are provided, fuel that moves back and forth and right and left can be efficiently introduced into the sub-chamber via any one of the check valves.

  According to the second aspect of the present invention, since the plurality of check valves are arranged at substantially equal angular intervals around the center of the sub chamber, the vehicle is accelerated, decelerated, turned right, and turned left. In either case, the fuel can be uniformly introduced into the sub-chamber.

  According to the configuration of claim 3, the number of check valves is two, and the line connecting the two check valves is inclined at an acute angle with respect to the longitudinal direction of the vehicle body. Even if the vehicle is not increased indefinitely, the fuel can be introduced into the sub-chamber when the vehicle is accelerating, decelerating, turning right, and turning left.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  1 to 6 show an embodiment of the present invention. FIG. 1 is a longitudinal sectional view of a fuel tank for an automobile, FIG. 2 is an enlarged sectional view taken along line 2-2 of FIG. 1, and FIG. FIG. 4 is a perspective view of the sub-chamber, FIG. 5 is a diagram for explaining the operation during acceleration / deceleration of the vehicle, and FIG. 6 is a diagram for explaining the operation when the vehicle is tilted back and forth.

  As shown in FIG. 1, the fuel tank T for automobiles includes a tank body 11 integrally blow-molded with a synthetic resin, and rubber blocks 41 are interposed between the upper surface and the lower surface 13 of the vehicle body. In this state, it is supported by bands 43 and 43 having both ends fixed to brackets 42 provided on the lower surface 13 of the vehicle body. A lid plate 17 that is in contact with the opening 11 c of the tank body 11 via a seal member 16 is fixed by a cap 18, and a substantially cylindrical sub-chamber 15 is supported on the lower surface of the lid plate 17. That is, the guide rods 44 extending upward from the upper end of the sub-chamber 15 are slidably fitted in the guide holes 17a and 17a opened on the lower surface of the cover plate 17, and are coil springs fitted on the outer periphery of the guide rods 44. By urging the sub-chamber 15 downward at 45..., The bottom surface of the sub-chamber 15 is fixed in contact with the lower wall 11 a of the tank body 11.

  A fuel pump module 19 supported on the lower surface of the lid plate 17 and extending into the sub-chamber 15 includes an in-tank type fuel pump 21, a feed pipe 22 extending from the fuel pump 21 through the lid plate 17 to the outside, A suction filter 23 as a fuel suction portion provided on the lower surface of the fuel pump 21 is provided. The fuel pump 21 is fixed to the inner surface of the sub chamber 15 and can move up and down with respect to the lid plate 17 by extending and contracting the coil springs 45. Therefore, the feed pipe 22 is configured to be flexible inside the tank body 11. The suction filter 23 is in contact with the bottom surface of the sub chamber 15.

  The lid plate 17 is provided with a return pipe 24 that returns excess fuel that has not been consumed by the engine to the sub-chamber 15, and a float valve 25 that closes when the fuel level reaches the upper limit. A steam discharge pipe 26 extending from the float valve 25 is connected to the vicinity of the fuel supply port at the upper end of the filler tube 27. The middle portion of the steam discharge pipe 26 is branched and connected to a canister (not shown).

  Next, the structure of the subchamber 15 will be described with reference to FIGS.

  The subchamber 15 is a bottomed cylindrical container whose upper surface is open and whose lower surface is closed. The first guide wall 15b, the second guide wall 15c, the ceiling wall 15d, and the tank body 11 are formed at the lower end of the side wall 15a. Two recesses 28F and 28R surrounded by the lower wall 11a are formed. The concave portions 28F and 28R are provided at both ends of the sub chamber 15 in the diameter direction. Valve ports 29F and 29R for communicating the inside and outside of the subchamber 15 are formed at the connection portions of the first guide wall 15b and the second guide wall 15c of the recesses 28F and 28R, and these valve ports 29F and 29R are reversed. Opened and closed by stop valves 30F and 30R.

  The check valves 30F and 30R are pivotally supported at the upper edges of the valve ports 29F and 29R by hinges 31 at their upper ends, and are closed to contact the stopper 32 and close the valve ports 29F and 29R. From there, it is possible to move between the valve opening position where it swings toward the inside of the sub chamber 15. A line L connecting the two check valves 30F and 30R is inclined at an acute angle (45 ° in the embodiment) with respect to the longitudinal direction of the vehicle body.

  Next, the operation of the embodiment of the present invention having the above configuration will be described.

  In FIG. 2, when the vehicle suddenly accelerates, the fuel in the tank body 11 moves to the rear of the vehicle body indicated by the arrow a, and the fuel that moves rearward along the first guide wall 15b of the front concave portion 28F becomes the front check valve. By swinging 30F backward about the hinge 31, the check valve 30F is opened, and the fuel in the tank body 11 flows into the sub chamber 15 through the valve hole 29F. When the vehicle suddenly decelerates, the fuel in the tank body 11 moves to the front of the vehicle body indicated by the arrow b, and the fuel that moves forward along the first guide wall 15b of the rear recess 28R passes through the rear check valve 30R. By swinging forward around the hinge 31, the check valve 30R is opened and the fuel in the tank body 11 flows into the sub chamber 15 through the valve hole 29R.

  When the vehicle turns to the right, the fuel in the tank body 11 moves to the left of the vehicle body as indicated by arrow c, and the fuel that moves to the left along the second guide wall 15c of the front recess 28F is the front check valve 30F. Is pivoted to the left around the hinge 31 to open the check valve 30F, and the fuel in the tank body 11 flows into the sub chamber 15 through the valve hole 29F. When the vehicle turns left, the fuel in the tank body 11 moves to the right of the vehicle body as indicated by the arrow d, and the fuel that moves to the right along the second guide wall 15c of the rear recess 28R is the rear check valve. By swinging 30R to the right around the hinge 31, the check valve 30R is opened, and the fuel in the tank body 11 flows into the sub chamber 15 through the valve hole 29R.

  Thus, the fuel introduced into the sub chamber 15 through the check valves 30F and 30R due to acceleration / deceleration and turning of the vehicle is not blocked by the check valves 30F and 30R and does not return to the tank body 11 side. Even if the remaining amount of fuel in the tank body 11 decreases, the fuel level in the sub-chamber 15 is kept high, and the suction filter 23 of the fuel pump 21 is exposed above the fuel level and the fuel supply is interrupted. The situation can be avoided in advance. In addition, since a special power source such as a jet pump driven by the fuel pump 21 is not required, there is no problem of increasing the power consumption of the vehicle.

  As described above, the two check valves 30F and 30R are arranged at positions shifted by 180 ° with respect to the center of the cylindrical sub-chamber 15, and a line L connecting the two check valves 30F and 30R is formed. Since the vehicle is tilted by 45 ° with respect to the longitudinal direction of the vehicle body and the lateral direction of the vehicle body, the fuel can be introduced into the sub-chamber 15 even when acceleration in any direction of the vehicle is applied to the vehicle.

  FIG. 5 illustrates the operation at the time of acceleration / deceleration of the vehicle. Even if the fuel level of the tank body 11 and the fuel level of the sub chamber 15 are the same in the initial state (see FIG. 5 (A)). Even if the vehicle is accelerated or decelerated, fuel is introduced into the sub-chamber 15 (see FIGS. 5B and 5C), and even if the vehicle returns to a steady running state, the fuel level in the sub-chamber 15 remains in the tank. It is maintained in a state higher than the fuel liquid level of the main body 11 (see FIG. 5D).

  FIG. 6 illustrates the action when the vehicle is tilted. Even if the fuel level of the tank body 11 and the fuel level of the sub chamber 15 are the same in the initial state (see FIG. 6A), Fuel is introduced into the subchamber 15 when the vehicle stops on the uphill or downhill (see FIGS. 6B and 6C), and the fuel level in the subchamber 15 even if the vehicle returns to the horizontal level. Is maintained higher than the fuel level of the tank body 11 (see FIG. 6D).

  The embodiments of the present invention have been described above, but various design changes can be made without departing from the scope of the present invention.

  For example, the sub-chamber 15 of the embodiment is cylindrical, but the shape is arbitrary.

  In the embodiment, the line L connecting the two check valves 30F and 30R is inclined by 45 ° with respect to the longitudinal direction of the vehicle body and the lateral direction of the vehicle body, but the inclination angle can be any acute angle.

  Further, although the sub chamber 15 of the embodiment includes the two check valves 30F and 30R, the number thereof may be three or more. In that case, it is desirable to arrange the check valves at equiangular intervals around the center of the sub-chamber 15. For example, when the number of check valves is three, the fuel can be most efficiently introduced into the sub-chamber 15 by arranging the check valves at intervals of 120 ° and arranging the check valves at intervals of 90 ° in the case of four.

  Further, the structure of the check valves 30F and 30R is not limited to that of the embodiment, and a check valve having any known structure can be adopted.

Vertical section of fuel tank for automobile 2-2 line enlarged sectional view of FIG. 3-3 enlarged sectional view of FIG. Perspective view of sub-chamber Action diagram when accelerating / decelerating the vehicle Action diagram when the vehicle is tilted back and forth

Explanation of symbols

11 Tank body 15 Subchamber 15a Side wall 21 Fuel pump 23 Suction filter (fuel suction part)
30F Check valve 30R Check valve L Line connecting two check valves

Claims (3)

A fuel suction portion (23) connected to the fuel pump (21) is provided inside the sub chamber (15) disposed inside the tank body (11), and the sub chamber (15) has the sub suction at the lower portion of the side wall (15a). In the sub-chamber structure of the fuel tank provided with check valves (30F, 30R) that allow the fuel to move from the outside to the inside of the chamber (15) and prevent the movement of the fuel from the inside to the outside,
A sub-chamber structure for a fuel tank, wherein the number of the check valves (30F, 30R) is plural.   2. The fuel tank sub-chamber according to claim 1, wherein the plurality of check valves (30 </ b> F, 30 </ b> R) are arranged at substantially equal angular intervals with a central portion of the sub-chamber (15) as a center. Construction.   The number of the check valves (30F, 30R) is two, and a line (L) connecting the two check valves (30F, 30R) is inclined at an acute angle with respect to the longitudinal direction of the vehicle body. The sub-chamber structure of the fuel tank according to claim 2.

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