JP2007064952A - Liquid level sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the remaining quantity of a liquid from being displayed erroneously in a liquid level sensor using a float, even if the level of the liquid varies, due to temporary inclination of its container. <P>SOLUTION: In the liquid level sensor 1 which has a regulating member 3 for regulating the horizontal movement of the float 4 put in the container containing the liquid, and detects the liquid level by vertical movement of the float 4, the float 4 and the regulating member 3 are provided with a locking means (A), which locks on and prevents upward and downward movements of the float 4, when their axes X1, X2 incline relative to a predetermined angle θ. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a liquid level sensor.

  Conventionally, as a device for detecting the amount of liquid such as an automobile gasoline tank or engine oil, a liquid level sensor that measures the liquid level by detecting the vertical position of the float using a float floating in the liquid is known. (See Patent Document 1).

  As shown in FIG. 16A, the liquid level sensor described in Patent Document 1 includes a cylindrical case 201 extending from the bottom wall to the top wall of a container 200 such as a gasoline tank. A float 202 is installed in the case 201 so as to be movable up and down, and further includes a guide shaft 203 that passes through the center of the float 202 and is arranged so that the float 202 can be moved up and down.

A communication hole 201 a through which liquid flows in and out is provided on the side surface of the bottom portion of the case 201, and a communication hole 201 b through which gas flows in and out is provided on the upper side surface of the case 201. As the liquid to be detected through the hole 201a flows into or out of the case 201, the float 202 is guided up and down by the guide shaft 203, and is provided in the float 202 as shown in FIG. The liquid level is measured by a reed switch 204 provided on the magnet 205 and the guide shaft 203 or case 201 over the entire vertical direction.
JP 2001-31654 A

  As in the liquid level sensor disclosed in Patent Document 1, in the case where the float 202 is simply guided by the guide shaft 203 so as to be movable up and down, as shown in FIG. Then, as the liquid in the container is biased toward the inclined side of the container, the liquid level rises to the position of L2 with respect to the original liquid level L1, as shown in FIG. If the liquid level falls in the opposite direction, the float 202 moves up and down following the liquid level rise and fall, and may output a signal with an incorrect value for the actual liquid level, that is, the remaining amount of the liquid. was there.

  Therefore, the present invention has an object to provide a liquid level sensor that solves the problem that the remaining amount of liquid in a container is erroneously displayed when the liquid level fluctuates due to the inclination of the container as described above. It is.

  In order to solve the above-mentioned problem, the invention according to claim 1 is a liquid level sensor that detects a liquid level by moving a float provided in a container containing liquid in a vertical direction. When the container is inclined at a predetermined angle, a locking means is provided for preventing the float from moving up and down.

  According to the present invention, when the container containing the liquid is inclined, the locking means prevents the float from moving up and down following the liquid level fluctuation.

  According to a second aspect of the present invention, there is provided a regulating member that regulates horizontal movement of a float provided in a container containing liquid, and the liquid level is detected by moving the float in the vertical direction. In the surface level sensor, the float and the restricting member are provided with locking means for locking the float and the restricting member to prevent the float from moving up and down when the axes are relatively inclined at a predetermined angle. Is.

  According to the present invention, when the container containing the liquid is inclined, when the regulating member is inclined at a predetermined angle with respect to the float, these are locked, and the float moves up and down following the liquid level fluctuation. Stop.

  According to a third aspect of the present invention, in the second aspect of the present invention, the locking means is formed such that surfaces of the float and the regulating member that face each other are uneven. is there.

  According to the present invention, when the container is inclined as described above, the concave and convex surfaces formed on the float and the regulating member come into contact with each other, and a frictional resistance is generated between them, thereby preventing the float from rising and falling. .

  The invention described in claim 4 is the invention described in claim 2 or 3, characterized in that the regulating member is provided on the outer peripheral surface side of the float.

  According to the present invention, when the container containing the liquid is inclined, the float can be prevented from rising and lowering by the locking means between the outer peripheral surface side of the float and the inner peripheral surface of the regulating member.

  The invention according to claim 5 is the invention according to claim 4, wherein the regulating member is formed in a cylindrical shape.

  According to the present invention, even when the regulating member is inclined in all directions, the outer peripheral surface of the float is locked to the inner circumferential surface of the regulating member, and the above-described action of preventing the float from moving up and down is performed.

  A sixth aspect of the invention is characterized in that, in the second or third aspect of the invention, the regulating member is provided so as to penetrate the float.

  According to the present invention, when the container containing the liquid is inclined, a frictional resistance is generated between the inner peripheral surface of the float and the outer peripheral surface of the restricting member, and the raising and lowering of the float can be prevented in the same manner as described above. .

  According to the seventh aspect of the present invention, there is provided a regulating member that regulates the horizontal movement of the float provided in the container containing the liquid, and the liquid level is detected by the float moving in the vertical direction. In the surface level sensor, a locking float is provided between the float and the regulating member so as to be movable up and down.

  According to the present invention, when the container containing the liquid is inclined, the locking float is locked to the float and the regulating member, so that the float can be prevented from moving up and down.

  The invention according to claim 8 is the invention according to claim 7, wherein the restriction member is constituted by a first restriction member provided in a horizontal cross section of the float and a second restriction member provided on an outer peripheral surface of the float, The locking float is provided between the float and the second regulating member.

  According to the present invention, the locking float provided on the outer peripheral surface of the float can be locked to the outer peripheral surface of the float and the inner peripheral surface of the second restricting member, thereby preventing the float from moving up and down.

  The invention according to claim 9 is the invention according to any one of claims 1 to 8, wherein the container containing the liquid is a container used in a vehicle.

  The present invention can be applied to containers such as a fuel tank or an oil tank of a vehicle to exhibit the above-described action.

  According to the first aspect of the invention, even if the liquid level temporarily fluctuates due to the inclination of the container due to the temporary inclination of the vehicle or the like, the locking means can prevent the float from moving in the vertical direction. The original liquid level in the container, that is, the actual remaining amount of the liquid can be detected without being affected by the fluctuation of the liquid level due to the inclination of the container, and erroneous display of the liquid amount can be prevented.

  According to the second aspect of the present invention, even if the liquid level temporarily fluctuates due to the inclination of the container due to the temporary inclination of the vehicle or the like, the restricting member is inclined at a predetermined angle with respect to the float, and the locking means Since the movement of the float in the vertical direction can be prevented, the same effect as described above can be exhibited.

According to invention of Claim 3, the said effect can be exhibited by the latching by an uneven surface.
According to invention of Claim 4, the said effect can be exhibited by the latching effect | action by the latching means provided between the outer peripheral surface of the float, and the inner peripheral surface of the control member.

  According to the fifth aspect of the present invention, since the regulating member is formed in a cylindrical shape, the above-described effect can be exhibited even when the regulating member is inclined in all directions together with the container.

  According to the sixth aspect of the present invention, it is possible to prevent the movement of the float during the inclination on the outer peripheral surface of the regulating member penetrating the float and the inner peripheral surface of the float. Therefore, even if a case is not provided on the outer periphery of the float, the float can be held and held as described above.

  According to the seventh aspect of the invention, by providing the locking float, when the container is inclined, the axis of the locking float is inclined with respect to the axis of the locking member and the float, and the locking float is By contacting the float and holding the float, the above effects can be exhibited.

  According to the invention of claim 8, the locking float mounted between the float and the second regulating member holds the float by being locked to the float and the second regulating member when the container is inclined. The said effect can be exhibited.

  According to the ninth aspect of the present invention, the liquid level sensor of the present invention is effective when applied to a liquid container such as a fuel tank or an oil tank in a vehicle such as an automobile.

  BEST MODE FOR CARRYING OUT THE INVENTION The best mode for carrying out the present invention will be described based on the embodiment shown in FIGS.

  1 to 3 show a first embodiment, and FIG. 1 shows a container 2 such as a fuel tank provided with a liquid level sensor 1 of the present invention.

  As shown in FIG. 1, in a container 2 such as a fuel tank or an oil tank of a vehicle that stores a liquid such as gasoline, a cylindrical case 3 made of a resin or the like that is less affected by fuel immersion is provided with a bottom wall of the container 2. Between the upper walls, they are fixed so as to be orthogonal to these walls and cover the outer periphery of the float 4 to be described later. A communication hole 3a opened in the container 2 is formed in the side surface at the lower end of the case 3, and a liquid such as gasoline in the container 2 flows into the case 3 from the communication hole 3a or the liquid in the case 3 Flows out into the container 2. Further, a communication hole 3 d opened in the container 2 is formed in the side surface portion at the upper end of the case 3 so that the gas in the case 3 flows out into the container 2 or the gas in the container 2 flows into the case 3. It is like that.

  In addition, a cylindrical float 4 made of a non-magnetic material resin and the like is accommodated in the case 3 so as to be movable up and down, and the center of the float 4 is vertically moved. A cylindrical through hole 4a penetrating in the direction is formed. A cylindrical guide shaft 5 that is less affected by the fuel immersion from the bottom wall to the upper wall of the case 3 and is made of a resin or the like of a nonmagnetic material is provided upright at the center of the case 3. A guide shaft 5 passes through the through hole 4a of the float 4 so that the float 4 can be raised and lowered. That is, when the case 3 and the guide shaft 5 are substantially perpendicular to the horizontal plane, as shown in FIG. 2 (a), between the outer peripheral surface 4d of the float 4 and the inner peripheral surface 3b of the case 3. There is a predetermined gap, and there is a predetermined gap between the inner peripheral surface 4 i of the through hole 4 a of the float 4 and the outer peripheral surface 5 a of the guide shaft 5, and the float 4 is between the guide shaft 5 and the case 3. Are arranged so as to be movable up and down.

  Since the case 3 and the guide shaft 5 both restrict movement of the float 4 in the horizontal direction, they are also referred to as restriction members in the present invention.

  In FIG. 2A, the upper corner portion (upper end portion) 4b and the lower corner portion (lower end portion) 4c of the cylindrical float 4 are formed at right angles or substantially right angles as shown in FIG. In the vicinity of the upper corner 4b and the lower corner 4c of the outer peripheral surface 4d of FIG. 4, an upper notch 4e and a lower notch 4f are engraved over the entire circumference of the outer surface 4d of the float 4. Due to the upper notch 4e and the lower notch 4f, the upper end and the lower end of the outer peripheral surface 4d of the float 4 have a rectangular shape with corners at the upper and lower outer ends in the longitudinal section of the float 4, and the float 4 is formed with a hook-like upper locking portion 4g and a lower locking portion 4h over the entire circumference. Also, the vertical cross-sectional shapes of the upper locking portion 4g, the lower locking portion 4h, the upper cutout portion 4e, and the lower cutout portion 4f are formed substantially the same.

  In addition, the inner peripheral surface 3b of the case 3 is formed with a convex / concave surface continuously at a predetermined equal interval from the bottom to the top of the case 3 in the longitudinal section. That is, the locking projections 3 d and the case side cutouts 3 c are alternately formed, and these are formed over the entire circumference of the case 3. The longitudinal cross-sectional shape of the case-side notch 3c is substantially the same as the vertical cross-sectional shape of the upper locking portion 4g and the lower locking portion 4h of the float 4, and the upper notch 4e of the float 4 and The vertical cross-sectional shape of the lower notch 4f is also formed to be substantially the same shape as the locking projection 3d of the case 3.

  The locking projection A of the case 3 and the upper locking portion 4g and the lower locking portion 4h on the float 4 side constitute locking means A.

  Inside the guide shaft 5, a plurality of reed switches 6, which are magnetoelectric conversion elements, are arranged in the axial direction with a predetermined interval, that is, from the bottom to the top, and this interval is the required liquid. It is set according to the surface detection accuracy. A magnet 7 made of a permanent magnet is embedded inside the float 4 on the inner peripheral surface 4i side. When the float 4 moves up and down, the reed switch 6 at a position facing the magnet 7 is turned on by a magnetic force. A signal is output to the outside, and the liquid level is detected based on this signal.

Next, the operation of the first embodiment will be described.
As shown in FIGS. 1 and 2 (a), when the container 2 is not inclined, the liquid in the case 3 increases or decreases through the communication hole 3a due to the increase or decrease in the liquid W in the container 2, and the liquid level L in the case 3 increases. Is moved up and down, the float 4 moves up and down in the horizontal state of FIG. By raising and lowering the float 4, the position of the magnet 7 is also raised and lowered, and the reed switch 6 at a position facing the magnet 7 is turned on by magnetic force to detect the liquid level, that is, the liquid amount.

  Next, when the vehicle or the like inclines due to undulations on the ground and the container 2 inclines, the case 3 and the guide shaft 5 incline as shown in FIG. At this time, since the liquid level of the liquid in the container 2 tends to maintain a horizontal state, the liquid level is inclined to L2 with respect to the original liquid level L1, as shown in FIG. Tilt. At this time, the float 4 floating on the liquid surface portion follows the liquid surface and tries to maintain a parallel posture, whereby the axis X1 of the float 4 is inclined with respect to the axis X2 of the case 3 and the guide shaft 5. That is, the inner wall 4i of the float 4 and the outer circumferential surface 5a of the guide shaft 5 are inclined in a swingable range in the gap between the outer circumferential surface 4d of the float 4 and the inner circumferential surface 3b of the case 3. When the relative angle θ between the axes X1 and X2 reaches a predetermined value, the upper locking portion 4g on one side of the float 4 is connected to the case on one side of the case 3, as shown in FIG. It latches by the latching convex part 3d so that it may enter into the side notch part 3c. Further, the lower locking portion 4h on the other side of the float 4 is also locked to the locking projection 3d so as to enter the case side cutout portion 3c on the other side. As a result, the contact load between the float 4 and the case 3 is increased, and a large frictional resistance is generated between the float 4 and the case 3 due to the locking of the irregularities, and the float 4 is pulled on the inner peripheral surface 3b of the case 3. It is held in that position. Thereafter, even if the container 2 is further inclined and the liquid level of the portion where the float 4 is located rises to L2 or more, the hooked float 4 continues to remain in that position, and the float 4 does not rise.

  As shown in FIG. 3, the angle θ at which the float 4 is caught on the case 3 is determined by the following equation (1) according to the outer diameter a of the float 4, the inner diameter b of the case 3, and the height H of the float 4. .

  As described above, the float 4 stays at the position where it is caught by the case 3, so that the reed switch 6 at that position is kept closed by the magnetic force of the magnet 7. Therefore, even if the inclination of the liquid level is further increased, a signal from the reed switch 6 at the above position is output to the outside. At this time, since the position detection by the reed switch 6 and the magnet 7 is a non-contact detection method, even if there is a gap between the guide shaft 5 and the float 4 due to the inclination, the reed switch 6 operates sufficiently and there is no problem. . The reed switch 6 may be installed not on the guide shaft 5 but on the surface of the guide shaft 5.

  Next, when the vehicle returns from the tilted state to the horizontal state, the container 2 also becomes horizontal at the same time, and the liquid level returns to the state perpendicular to the case 3 and the guide shaft 5, and the axis X1 of the float 4 is set to the case 3 and the guide. The upper locking portion 4g and the lower locking portion 4h of the float 4 that are parallel to the axis X2 of the shaft 5 and hooked on the inner peripheral surface 3b of the case 3 as described above are disengaged and are again driven by the liquid level fluctuation. The float 4 moves up and down, and normal liquid level detection is performed.

  The angle at which the float 4 is detached from the case 3 is when the float 4 is smaller than the angle θ. However, even when the inclination angle of the float 4 is smaller than the angle θ, the hooked state of the float 4 continues. If it is, the float 4 is detached from the case 3 due to the swinging motion of the float 4 due to a minute liquid level swing due to the vibration of the vehicle or the like. Therefore, even if the float 4 is caught in the case 3 even though the liquid level is in a normal substantially horizontal state, the catch is immediately released, and the float 4 returns to the original floating position. Normal liquid level detection is performed.

  The gap between the float 4 and the guide shaft 5 and the gap between the float 4 and the case 3 are set as desired depending on the shape of the container 2. For example, if the liquid level sensor 1 is flat and has a large liquid level and the liquid level sensor 1 is at the end of the container 2, a large error occurs in the measurement even if the liquid level is small. The interval is set small so that the float 4 is locked at a small time. Further, when the container 2 is deep and the liquid level measurement is not easily affected by the inclination of the liquid level, this interval is set to be large to some extent so that the float 4 is locked and held by a large inclination angle of the liquid level. Also good.

  As described above, according to the present invention, when the liquid container is temporarily inclined, or when applied to a container such as a fuel tank of a vehicle, the vehicle is temporarily inclined, accelerated or decelerated, and temporarily turned. It is possible to accurately detect the liquid level in the container 2, that is, the remaining amount of liquid, without being affected by the inclination of the liquid level. In addition, since the upper locking portion 4g and the lower locking portion 4h of the float 4 and the locking projection 3d of the case 3 are formed at right angles, the float 4 is easily caught when inclined, and the float 4 The retention of can be increased.

  FIG. 4 shows a second embodiment, which is a modification of the locking means A of the first embodiment. In the float 4 according to the second embodiment, the upper notch 24e and the lower notch 24f are formed in a trapezoidal shape with the outside expanded, and the upper and lower wall surfaces 24j of the upper notch 24e and the lower notch 24f are inclined in the vertical direction. Is. The notches 24e and 24f are engraved over the entire circumference of the outer peripheral surface 4d of the float 4. Further, the upper corner portion 24b and the lower corner portion 24c on the outer peripheral surface 4d of the float 4 are cut at the corners, and the upper surface portion and the lower end portion of the float 4 are triangularly formed toward the outside of the float 4 by the wall surface 24j. An upper locking portion 24g and a lower locking portion 24h are formed. The upper locking portion 24g and the lower locking portion 24h are also formed over the entire circumference of the outer peripheral surface 4d of the float 4.

  Further, on the inner peripheral surface 3b of the case 3, a locking projection 23d on the case side having the same shape as the upper locking portion 24g and the lower locking portion 24h of the float 4 is projected, and the locking projection A case-side notch 23c having the same shape as the upper notch 24e and the lower notch 24f of the float 4 is formed between the parts 23d and 23d. Further, the case-side cutout 23 c is carved over the entire circumference of the inner peripheral surface 3 b of the case 3. A plurality of the locking projections 23d and the case-side cutouts 23c are alternately provided at regular intervals from the bottom to the top of the case 3.

  The locking means A is constituted by the locking projection 23d of the case 3 and the locking portions 24g and 24h on the float 4 side.

  Since other configurations are the same as those of the first embodiment, the same parts as those described above are denoted by the same reference numerals as those described above, and the description thereof is omitted.

  In Example 2, when the container 2 is in a horizontal state, the state shown in FIG. 4A is obtained. When the float 4 is inclined at the angle θ, the state shown in FIG. The portion 24g and the lower locking portion 24h are locked to the locking projection 23d of the case 3, and the same operations and effects as in the first embodiment are obtained. In the second embodiment, the upper locking portion 24g and the lower locking portion 24h of the float 4 and the locking protrusion 23d of the case 3 are formed as triangular protrusions. In comparison, the contact load of the float 4 catching when the liquid level is inclined is reduced, and compared to the first embodiment, the float 4 is less likely to catch on the case 3 and can meet the demand for easy removal.

  FIG. 5 shows a third embodiment. The float 4 of the third embodiment is a modification of the upper locking portion 4g and the lower locking portion 4h of the float 4 of the first embodiment and the locking projection 3d of the case 3. In the example, the upper locking portion 34g and the lower locking portion 34h of the float 4 are formed by arc-shaped protrusions projecting outward, in the embodiment of FIG. 5, a semicircular protrusion. Moreover, the middle part 34k between both the latching | locking parts 34g and 34h is formed in the diameter smaller than both the latching | locking parts 34g and 34h.

  Further, the locking projection 33d in the case 3 is formed by an arc shape protruding inward with the same shape as the locking portions 34g and 34h, and a semicircular protrusion in the embodiment of FIG. Further, a plurality of the locking projections 33d are formed at predetermined intervals from the bottom to the top of the case 3, and a case-side notch 33c into which the locking portions 34g and 34h are fitted is formed therebetween. . The locking portions 34 g and 34 h are formed over the entire circumference of the float 4, and the case-side notch 33 c and the locking projection 33 d are formed on the inner peripheral surface of the case 3 over the entire circumference.

  The locking means A is constituted by the locking projection 33d of the case 3 and the locking portions 34g and 34h on the float 4 side.

  Since other configurations are the same as those of the first embodiment, the same portions are denoted by the same reference numerals and the description thereof is omitted.

  In the third embodiment, when the container 2 is in the horizontal state, the state shown in FIG. 5A is obtained. When the float 4 is inclined at the angle θ, the state shown in FIG. The upper locking portion 34g and the lower locking portion 34h are locked to the locking projection 33d of the case 3, and the same operations and effects as those of the first embodiment are achieved. In the present invention, the upper locking portion 34g and the lower locking portion 34h of the float 4 and the locking projection 33d on the case 3 side are formed as semicircular protrusions, so that compared to the second embodiment. Thus, the contact load of the float 4 caught when the liquid level is inclined is smaller than that in the first embodiment and larger than that in the second embodiment. For this reason, it is possible to meet the demand for setting the degree of catching and detachment between the float 4 and the case 3 to an intermediate state between the first embodiment and the second embodiment.

  FIGS. 6 and 7 show a fourth embodiment. In the fourth embodiment, the case 3 in the first embodiment is eliminated, and only the guide shaft 5 has the same effects as the first embodiment.

  Also in the fourth embodiment, as shown in FIG. 6A, a through hole 4a penetrating in the vertical direction is formed at the center of the cylindrical float 4 in the same manner as the previous embodiment, and the guide shaft 5 is formed in the through hole 4a. The guide shaft 5 is erected from the bottom wall to the top wall of the container 2. As a result, the float 4 is supported by the guide shaft 5 inside the through-hole 4a, and the float 4 is guided by the guide shaft 5 to move up and down.

  Further, the upper corner portion 44b and the lower corner portion 44c of the inner peripheral surface 4i of the through hole 4a in the cylindrical float 4 are formed at right angles, and the inner peripheral surface of the float 4 is in the vicinity of the upper corner portion 44b and the lower corner portion 44c. An upper notch 44e and a lower notch 44f are formed on the entire circumference of 4i. Due to the upper notch 44e and the lower notch 44f, the upper end and the lower end of the inner peripheral surface 4i of the float 4 are quadrangular with vertical corners, and a bowl-shaped upper portion over the entire circumference of the float 4. A stop portion 44g and a lower locking portion 44h are formed.

  Further, on the outer peripheral surface 5a of the guide shaft 5, guide shaft side notches 5b extending over the entire circumference of the outer peripheral surface 5a and locking projections 5c on the guide shaft side extending over the entire outer periphery of the outer peripheral surface 5a are alternately arranged in the axial direction. Is formed. That is, by these, it forms in the uneven surface which continued from the bottom part of the guide shaft 5 to the upper part at predetermined intervals. The guide shaft side notch 5b is engraved in the same shape as the upper locking portion 44g and the lower locking portion 44h of the float 4, and the upper notch 44e and the lower notch 44f on the inner surface 4i of the float 4 are It is formed in the same manner as the locking projection 5c on the guide shaft side.

  The locking means A is constituted by the locking portions 44g and 44h on the float 4 side and the locking convex portion 5c on the guide shaft 5 side. The float 4 is provided with a magnet 7 as described above, and the guide shaft 5 is provided with a reed switch 6 as described above.

  In the fourth embodiment, the container 2 is in the state shown in FIG. When the liquid level is inclined from L1 to L2 due to the inclination of the container 2 as shown in FIG. 6B, the float 4 floating on the liquid level portion follows the liquid level and tries to maintain a parallel posture. As a result, the axis X1 of the float 4 is inclined with respect to the axis X2 of the guide shaft 5 provided in the container 2, and the float 4 is located between the inner peripheral surface 4i of the float 4 and the outer peripheral surface 5a of the guide shaft 5. It tilts in a swingable range in the gap. Then, one side of the upper locking portion 44g on the inner peripheral surface 4i of the float 4 enters the guide shaft side cutout portion 5b and is locked to the locking projection 5c on the guide shaft side, and the other side of the lower locking portion 44h. This side enters the notch 5b on the guide shaft side and is locked by the locking projection 5c on the guide shaft side, and the contact load between the float 4 and the guide shaft 5 increases. At this time, a large frictional resistance is generated between the float 4 and the guide shaft 5, and the float 4 is caught by the guide shaft 5 and held at that position. Even if the container 2 is further tilted thereafter, the caught float 4 remains in that position.

  The angle at which the float 4 is caught with the guide shaft 5 is determined by the following equation (2) according to the outer diameter c of the guide shaft 5, the inner diameter d of the float 4, and the height H of the float 4, as shown in FIG. It is done.

  Further, when the liquid level is inclined as described above, the float 4 remains at the position where it is caught by the guide shaft 5, so that the guide shaft 5 at the position facing the magnet 7 of the float 4 is the same as in the first embodiment. The reed switch 6 is closed by the magnetic force of the magnet 7, and a signal of the closing operation is output to the outside.

  Next, when the vehicle returns from the tilted state to the horizontal state, the container 2 also becomes horizontal at the same time, and the liquid level returns to the state perpendicular to the guide shaft 5, and the axis line X1 of the float 4 and the axis line X2 of the guide shaft 5 are In parallel, the float 4 that has been hooked on the locking projection 5c on the guide shaft side as described above comes off, and the float 4 moves up and down again following the rise and fall of the liquid level.

  The angle θ at which the float 4 is detached from the guide shaft 5 is an angle that is smaller than the angle θ at which the float 4 is hooked on the guide shaft 5 described in the equation (2), but the inclination angle of the float 4 is When the float 4 continues to be caught even when the angle θ is smaller than the angle θ, the float 4 is detached from the guide shaft 5 due to the swinging movement of the float 4 due to a minute liquid level swing due to vehicle vibration or the like. . Therefore, even if the float 4 is caught on the guide shaft 5 even though the liquid level is in a normal substantially horizontal state, the catch is immediately released and the float 4 returns to the original floating position. Normal liquid level detection is performed.

As described above, also in the fourth embodiment, the same operations and effects as the first embodiment are obtained.
Further, according to the fourth embodiment, the guide shaft 5 has the lifting / lowering guide function of the float 4 and the holding mechanism of the reed switch 6, so that the apparatus can be reduced in size and cost.

  Note that the case 3 as described above may be provided on the outer periphery of the float 4 in order to eliminate the influence of the vibration of the liquid level and the short-time inclination on the float. In this case, it is not necessary to form the uneven surface on the inner surface of the case 3.

  FIG. 8 shows a fifth embodiment. The float 4 of the fifth embodiment includes notches 44e and 44f and locking portions 44g and 44h formed on the inner peripheral surface 4i of the float 4 of the fourth embodiment. The float 4 of the second embodiment shown in FIG. The upper notch portion 54e, the lower notch portion 54f, the upper locking portion 54g, and the lower notch portion 54h having the same shape as the notches 24e and 24f and the locking portions 24g and 24h formed on the outer peripheral surface 4d of In the guide shaft 5, the guide shaft side notch portion 5 b and the guide shaft side locking projection portion 5 c formed on the outer peripheral surface of the guide shaft 5 of the fourth embodiment are formed in the case 3 of the second embodiment shown in FIG. 4. The guide shaft side cutout portion 55b and the guide shaft side lock projection portion 55c are formed in the same shape as the case side cutout portion 23c formed on the inner peripheral surface and the case side lock projection portion 23d. The guide shaft side notch 55b and the guide shaft side locking projection 55c are formed over the entire circumference of the outer peripheral surface of the guide shaft 5 and are continuous at a predetermined interval in the axial direction, as described above. Is provided.

Other structures are the same as those in the fourth embodiment.
Also in the fifth embodiment, when the container 2 is in a horizontal state, the state shown in FIG. 8A is obtained, and when the container 2 is inclined, the state shown in FIG. 8B is obtained, and the liquid level is the same as that in the fourth embodiment shown in FIG. Detection can be performed. Furthermore, the degree of locking between the float 4 and the guide shaft 5 can be made the same as in the second embodiment shown in FIG.

  FIG. 9 shows a sixth embodiment. The float 4 of the sixth embodiment is formed in the same structure as the float 4 of the fourth embodiment, and an upper notch portion 64e similar to that of the fourth embodiment is formed on the inner peripheral surface 4i of the float 4. A notch portion 64f, an upper locking portion 64g, and a lower locking portion 64h are formed.

  Further, on the outer periphery of the guide shaft 5, the engagement on the case side of the third embodiment shown in FIG. 5 is used instead of the locking projection 5 c on the guide shaft side formed on the outer peripheral surface of the guide shaft 5 of the fourth embodiment. A locking projection 65c on the guide shaft side having the same shape as the locking projection 34d is formed. That is, the semicircular guide shaft side locking convex portion 65c and the guide shaft side cutout portion 65b are formed on the outer peripheral surface of the guide shaft 5 as in the fourth embodiment. And provided continuously at predetermined intervals in the axial direction.

Other structures are the same as those in the fourth embodiment.
Also in the sixth embodiment, when the container 2 is in the horizontal state, it is in the state shown in FIG. 9A, and when the container 2 is tilted, it is in the state shown in FIG. 9B. Liquid level detection can be performed. Further, as in the sixth embodiment, the locking portions 64g and 64h of the float 4 are formed in a square shape, and the locking convex portion 65c on the guide shaft side is formed in a semicircular protrusion. The locking and releasing operation of the float 4 is in an intermediate state between the structure of the fourth embodiment shown in FIG. 6 and the structure of the embodiment 5 shown in FIG.

  FIG. 10 shows a case where the locking means A of the first embodiment is applied to a displacer type liquid level sensor.

  In the seventh embodiment, as shown in FIG. 10, a cylindrical float (displacer) 74 that is less affected by fuel immersion and that is made of a non-magnetic resin or the like and that is long in the vertical direction is disposed inside the case 3. A cylindrical elongated hole 74a is formed in the center of the lower portion of the float 74 upward from the lower surface. A spring 71 wound about the same diameter as the transverse cross section of the elongated hole 74a is inserted into the elongated hole 74a. The spring 71 is in contact with the upper surface 74b of the elongated hole 74a and the bottom wall of the case 3. Yes.

  Further, a predetermined gap is provided between the outer peripheral surface 74d of the float 74 and the inner peripheral surface 3b of the case 3, and the float 74 is disposed so as to be movable up and down in the case 3.

  Further, a resistor base 8 having a lead wire at the upper end is attached to the entire periphery of the lower end of the float 74 in the gap at a predetermined interval in the vertical direction, and the bottom of the case 3 is slightly larger than the lift width of the float 74. A brush 9 having a long ring shape and having a lead wire is provided upward, and the side surface of the resistance base 8 and the end of the brush 9 are in contact with 9a. When the float 74 is lifted and lowered by the buoyancy caused by the increase or decrease of the liquid while being supported by the spring 7, the distance from the end portion 8 a of the resistance base 8 to the end portion 9 a of the brush 9 changes depending on the lift position of the float 74, and the resistance value Changes, and the changed resistance value is measured by an external device (not shown) to detect the liquid level.

  As a method for detecting the displacement of the float 74 as described above, the ring-shaped brush 9 is provided at the lowermost part of the float 74, and the resistance base 8 is brought into contact with the brush 9 from the bottom of the case 3. You may install in. Furthermore, other known methods may be employed as the float displacement detection method.

  Similar to the first embodiment, a convex locking portion 74g having upper and lower corners formed at right angles is projected outward from the upper end of the outer peripheral surface 74d of the float 74.

  Further, the upper inner peripheral surface 3b of the case 3 is formed with a convex-concave surface continuously at predetermined equal intervals from the upper part of the case 3 downward to a predetermined interval in the longitudinal section. That is, the locking projections 73 d and the notches 73 c are alternately formed, and these are formed over the entire circumference of the case 3. The vertical cross-sectional shape of the notch 73c is formed in substantially the same shape as the vertical cross-sectional shape of the locking portion 74g of the float 74.

  The locking projection A of the case 3 and the locking portion 74g of the float 74 constitute locking means A.

  In the seventh embodiment, when the container 2 is in the horizontal state, the float 74 is in a substantially upright state as shown in FIG. 10A, and the float 74 is moved up and down by the increase / decrease of the liquid, and normal liquid level detection is performed. As shown in FIG. 10 (b), when the container 2 is inclined and the liquid level is changed from L1 to L2, the case 3 is inclined together with the container 2 as shown in FIG. 10 (b), but the float 74 is buoyant. As a result, the locking portion 74g of the float 74 enters the notch 73c on the case 3 side and locks to the locking projection 73d of the case 3. Therefore, even if the liquid level further rises, the float 74 is prevented from moving upward, and the liquid level at the locked position is detected. Therefore, also in the present Example 7, there exists an effect | action similar to the said Example 1, and an effect.

FIG. 11 shows an eighth embodiment.
The eighth embodiment is a modification of the locking means A between the float and the case in the first embodiment. An annular locking float is provided as the locking means, and the same effect as in the first embodiment can be obtained. It is.

  Also in the eighth embodiment, as shown in FIG. 11A, a through hole 84a penetrating in the vertical direction is formed at the center of the cylindrical float 84 as in the first embodiment, and a guide is provided in the through hole 84a. The shaft 5 is inserted with a predetermined gap, and the guide shaft 5 is erected from the bottom wall to the top wall of the container 3. As a result, the float 84 is held by the guide shaft 5 inside the through hole 84a, and the float 84 moves up and down with its movable direction being restricted by the guide shaft 5 in the vertical direction.

  Further, the outer peripheral surface 84b of the body portion of the cylindrical float 84 is formed to be smaller in diameter than the inner diameter of the case 2, and an upper hook portion 84g and a lower hook portion 84h projecting outward are formed on the upper and lower ends of the float 84. Is formed. An annular locking float 80 having a cylindrical through hole 80a penetrating in the vertical direction at the center is disposed on the outer peripheral surface 84b. The locking float 80 is formed in a cylindrical shape, and the vertical cross-sectional shape of the flesh is formed in a vertically long rectangle. Furthermore, there is a predetermined gap between the inner peripheral surface 80b of the through hole 80a, that is, the inner peripheral surface 80b of the locking float 80 and the outer peripheral surface 84b of the float 84, and the outer peripheral surface 80c of the locking float 80 A predetermined gap is also formed between the case 3 and the inner peripheral surface 3b. As will be described later, the amount of the gap is set such that the locking float 80 is inclined by a predetermined amount and exhibits a function as a stopper. The locking float 80 is movable between the upper flange 84g and the lower flange 84h.

  The locking float 80 is made of a material having a high frictional resistance, such as a non-magnetic resin, which is less affected by the immersion of the fuel.

  Since the other structure is the same as that of the first embodiment, the same parts are denoted by the same reference numerals and the description thereof is omitted.

  The float 84 is provided with the magnet 7 as in the first embodiment, and the guide shaft 5 is provided with the reed switch 6 as in the first embodiment, but these are not shown.

  In the eighth embodiment, when the container 2 is in a horizontal state, the axes of the case 3, the float 84, and the locking float 80 are substantially parallel as shown in FIG. 11A. Both move up and down and normal liquid level detection is performed.

  Next, when the container 2 is inclined and the case 3 is inclined as shown in FIG. 11B and the liquid level is inclined from L1 to L2, the float 84 is moved by the guide shaft 5 as shown in FIG. In contrast, the locking float 80 is inclined so as to be parallel to the guide shaft 5 and the case 3, and the axial center of the locking float 80 tends to be vertical due to buoyancy, that is, to maintain an upright posture. Accordingly, the axis X1 of the locking float 80 is inclined with respect to the axis X2 of the case 3 and the float 84, and the locking float 80 is located between the inner peripheral surface 80b of the locking float 80 and the outer peripheral surface 84b of the float 84. And a predetermined gap between the outer peripheral surface 80 c of the locking float 80 and the inner peripheral surface 3 b of the case 3.

  Then, one side of the upper locking portion 80d and the other side of the lower locking portion 80e on the outer peripheral surface 80c of the locking float 80 are in contact with the inner peripheral surface 3b of the case 3, and the inner periphery of the locking float 80 is further increased. One side of the upper locking portion 80d on the surface 80b and the other side of the lower locking portion 80e are in contact with the outer peripheral surface 84b of the float 84, and the locking float 80, the float 84, and the case increase as the inclination angle of the case 3 increases. 3 contact load becomes large. As a result, the locking float 80 is engulfed between the float 84 and the case 3, which becomes a stopper, prevents the float 84 from moving, and the float 84 is held at that position. Thereafter, even if the container 2 is further inclined and the liquid level rises to L2 or more, the float 84 continues to remain in that position.

  Accordingly, in the same manner as in the first embodiment, at the position where the float 84 stays as described above, the magnet 7 of the float 84 (not shown) closes the reed switch 6 of the guide shaft 5 and outputs the signal of the closing operation to the outside. To do. Therefore, it is possible to eliminate the liquid level detection error at the time of tilting.

  Next, when the vehicle returns to the horizontal state from the inclined state, the liquid level returns to a state perpendicular to the float 84, the axis line X1 of the locking float 80 is parallel to the axis line X2 of the case 3 and the float 74, and As described above, the float 84 and the locking float 80 that are locked to the case 3 are released, and the float 84 moves up and down again following the rise and fall of the liquid level.

As described above, also in the eighth embodiment, the same operations and effects as the first embodiment are obtained.
According to the eighth embodiment, it is not necessary to form an uneven surface on the side surface of the guide shaft 5 or the case 3 as in the first embodiment, only by attaching the locking float 80 to the outer periphery of the float 84. The stop means can be easily formed. Further, since the float 84 is not caught on the uneven surface of the case 3 or the guide shaft 5, the float 84 can be smoothly returned to the original floating position when the liquid level is in a normal substantially horizontal state. Is called.

  Furthermore, the locking float 80 is not detached from the outer peripheral surface 84b of the float 84 by providing the upper flange 84g and the lower flange 84h.

  FIG. 12 shows the ninth embodiment, in which the upper flange 84g of the eighth embodiment shown in FIG. 11 is eliminated and the upper part of the annular locking float 80 serving as the locking means is opened. FIG. 12A shows the container in a horizontal state, and FIG. 12B shows an inclined state.

  Since the other structure is the same as that of the said Example 8, the same code | symbol is attached | subjected to the same part and the description is abbreviate | omitted.

  According to the ninth embodiment, since the upper flange portion 84g is not provided, the float 84 can be easily molded as compared with the float according to the eighth embodiment. Further, the locking float 80 is formed on the outer peripheral surface of the float 84. It is easy to fit into 84b. Further, it is possible to prevent the locking float 80 from being detached from below the float 84.

  FIG. 13 shows the tenth embodiment, in which the lower collar portion 84h of the eighth embodiment shown in FIG. 11 is eliminated and the lower portion of the annular locking float 80 serving as the locking means is opened.

  Since the other structure is the same as that of the said Example 8, the same code | symbol is attached | subjected to the same part and the description is abbreviate | omitted.

  In the tenth embodiment, the same effect as in the ninth embodiment can be obtained. Further, it is possible to prevent the locking float 80 from being detached from above the float 84.

  Note that the locking means of the eighth, ninth, and tenth embodiments only require that the locking float 80 be locked to the inner peripheral surface 3b of the case 3 and the outer peripheral surface 84b of the float 84. Both of the parts 84h may be eliminated.

  FIG. 14 shows Example 11, in which the positional relationship between the float 84 and the locking float 80 in FIG. 11 is reversed, and the locking float 90 is locked to the guide shaft 5 and the float 94. It is. That is, as shown in FIG. 14 (a), the gap between the outer peripheral surface of the guide shaft 5 and the inner peripheral surface 94b of the float 94 is increased, and the locking portion is a locking means as described above. The float 90 is interposed, and the outer peripheral surface of the float 94 is brought close to the inner peripheral surface 3 b of the case 3.

  The clearance between the outer peripheral surface of the guide shaft 5 and the inner peripheral surface 90b of the locking float 90, and the clearance between the outer peripheral surface 90c of the locking float 90 and the inner peripheral surface 94b of the float 94 are the same as in the eighth embodiment. Similarly, when the case 3 and the float 94 are inclined by a predetermined amount, the locking float 90 is set so as to exhibit a function as a stopper.

  Further, an upper flange portion 94g and a lower flange portion 94h projecting inward are formed at the upper and lower ends of the float 94, and the locking float 90 can be moved between the upper flange portion 94g and the lower flange portion 94h. Yes.

  Further, the outer peripheral surface of the float 94 is held so as to be movable up and down by the inner peripheral surface 3 b of the case 3, and its movable direction is regulated by the case 3 in the vertical direction so as to move up and down.

  Since the other structure is the same as that of the said Example 8, the same code | symbol is attached | subjected to the same part and the description is abbreviate | omitted.

  In Example 11, when the container 2 is inclined and the case 3 and the guide shaft 5 are inclined as shown in FIG. 14B and the liquid level is inclined from L1 to L2, the locking float 90 is changed to the float 94. The upper locking portion 90d and the lower locking portion 90e of the locking float 90 come into contact with the inner peripheral surface 94b of the float 94 and the outer peripheral surface of the guide shaft 5 as shown in FIG. 94 is held in that position.

Therefore, also in the present Example 11, there exists an effect | action similar to the said Example 8, and an effect.
The upper flange 94g and the lower flange 94h may be omitted as in the ninth and tenth embodiments, and one of the upper and lower portions of the locking float 90 may be opened, and the upper flange 94g. And the lower flange 94h may be eliminated.

FIG. 15 shows a displacer type application of the locking means of the eighth embodiment.
The float 104 and the case 3 according to the twelfth embodiment have a shape in which the locking portion 74g and the uneven portions 73c and 73d shown in FIG. 10 are eliminated, and the other structures of the float 104 and the case 3 are the float shown in FIG. 74 and the case 3 have the same structure, and the liquid level detection means is the same as described above. Therefore, the same parts as those in FIG. 10 are denoted by the same reference numerals as those in FIG.

  The embodiment 12 is equipped with an annular locking float 100 which is a locking means in which a cylindrical through hole 100a penetrating in the vertical direction is formed in the center between the float 104 and the case 3. is there. There is a predetermined gap between the outer peripheral surface 104 d of the float 104 and the inner peripheral surface 100 b of the locking float 100, and between the outer peripheral surface 100 c of the locking float 100 and the inner peripheral surface 3 b of the case 3. Has a predetermined gap, and the locking float 100 moves up and down in the annular gap between the float 104 and the case 3.

  In the twelfth embodiment, when the container 2 is in the horizontal state, as shown in FIG. 15A, the axes of the float 104 and the locking float 100 are substantially parallel to each other, and both the float 104 and the locking float 100 are caused by the increase or decrease of the liquid. The liquid level is raised and lowered to perform normal liquid level detection.

  Next, when the container 2 is inclined and the case 3 is inclined as shown in FIG. 15B and the liquid level is inclined from L1 to L2, the float 104 is moved together with the spring 101 as shown in FIG. In contrast, the locking float 100 tends to keep its axis X1 vertical by buoyancy, that is, to maintain an upright posture. As a result, the axis line X1 of the locking float 100 is inclined with respect to the axis line X2 of the float 104, and the locking float 100 has a predetermined distance between the inner peripheral surface 100b of the locking float 100 and the outer peripheral surface 104b of the float 104. The gap and the inclination are inclined within a swingable range in a predetermined gap between the outer peripheral surface 100 c of the locking float 100 and the inner peripheral surface 3 b of the case 3.

  Then, one side of the upper locking portion 100d and the other side of the lower locking portion 100e on the outer peripheral surface 100c of the locking float 100 come into contact with the inner peripheral surface 3b of the case 3, and further, the inner periphery of the locking float 100 One side of the upper locking portion 100d and the other side of the lower locking portion 100e on the surface 100b are in contact with the outer peripheral surface 104b of the float 104, and the locking float 100 and the float 104 are increased as the inclination angle of the case 3 increases. The contact load of case 3 increases. As a result, the locking float 100 is engulfed between the float 104 and the case 3, and this acts as a stopper, preventing the movement of the float 104 and holding the float 104 in that position. Therefore, the present Example 12 also has the same operation and effect as the Example 10.

  In the above embodiment, the cylindrical case and the columnar (rod-shaped) guide shaft are used to lock the float with respect to the inclination in all directions. When it is desired to change to the above, it is not limited to the cylindrical shape as described above, and other shapes may be used.

  In addition, the shapes of the locking projections and the locking portions provided on the float, case, and guide shaft are not limited to the triangle, square, and semicircle, and other shapes may be used. . Furthermore, these shapes may be used in combination as desired.

  The liquid level sensor of the present invention can be used as a fuel tank, an oil tank or the like in a vehicle such as an automobile, or a liquid container other than the vehicle, for detecting the liquid level or amount of the stored liquid.

1 is a side sectional view showing Example 1 of the present invention. FIG. 2 is an enlarged longitudinal sectional view of the liquid level sensor in FIG. 1, where (a) shows a horizontal state of the container and (b) shows a state where the container is inclined. Sectional drawing which shows the relationship of the angle which the float in FIG.2 (b) catches on a case. It is a longitudinal cross-sectional view which shows Example 2 of this invention, (a) is a horizontal state of a container, (b) shows the state which the container inclined. It is a longitudinal cross-sectional view which shows Example 3 of this invention, (a) is a horizontal state of a container, (b) shows the state which the container inclined. It is a longitudinal cross-sectional view which shows Example 4 of this invention, (a) is a horizontal state of a container, (b) shows the state which the container inclined. Sectional drawing which shows the relationship of the angle which the float in FIG.6 (b) catches on a guide shaft. It is a longitudinal cross-sectional view which shows Example 5 of this invention, (a) is a horizontal state of a container, (b) shows the state which the container inclined. It is a longitudinal cross-sectional view which shows Example 6 of this invention, (a) is a horizontal state of a container, (b) shows the state which the container inclined. It is a longitudinal cross-sectional view which shows Example 7 of this invention, (a) is a horizontal state of a container, (b) shows the state which the container inclined. It is a longitudinal cross-sectional view which shows Example 8 of this invention, (a) is a horizontal state of a container, (b) shows the state which the container inclined. It is a longitudinal cross-sectional view which shows Example 9 of this invention, (a) is a horizontal state of a container, (b) shows the state which the container inclined. It is a longitudinal cross-sectional view which shows Example 10 of this invention, (a) is a horizontal state of a container, (b) shows the state which the container inclined. It is a longitudinal cross-sectional view which shows Example 11 of this invention, (a) is a horizontal state of a container, (b) shows the state which the container inclined. It is a longitudinal cross-sectional view which shows Example 12 of this invention, (a) is a horizontal state of a container, (b) shows the state which the container inclined. The container and the liquid level sensor which used the conventional float are shown, (a) is a longitudinal cross-sectional view, (b) is an expanded sectional view of the liquid level sensor part of (a). (A) is sectional drawing which shows the state which the container of FIG. 16 inclined and the liquid level with respect to the container displaced, (b) is an enlarged view of the liquid level sensor part of (a).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Liquid level sensor 2 Container 3 Case 4,74,84,94 which is restriction member Float 5 Guide shaft which is restriction member A Locking means 3d, 23d, 33d Locking convex part 4g, 4h, 24g, 24h, 34g , 34h, 44g, 44h Locking part 80, 90 Locking float

Claims (9)

  In a liquid level sensor that detects the liquid level by moving the float provided in the container containing the liquid in the vertical direction, the float is prevented from rising and falling when the container is inclined at a predetermined angle. A liquid level sensor characterized in that a locking means is provided.   A liquid level sensor in which a regulating member for regulating horizontal movement of a float provided in a container containing liquid is provided, and the liquid level is detected by moving the float in the vertical direction. A liquid level sensor characterized in that the regulating member is provided with a locking means that locks and prevents the float from moving up and down when these axes are inclined at a predetermined angle.   3. The liquid level sensor according to claim 2, wherein the locking means is formed by making the surfaces of the float and the regulating member facing each other have an uneven surface.   4. The liquid level sensor according to claim 2, wherein the regulating member is provided on the outer peripheral surface side of the float.   The liquid level sensor according to claim 4, wherein the regulating member is formed in a cylindrical shape.   4. The liquid level sensor according to claim 2, wherein the regulating member is provided so as to penetrate the float.   A liquid level sensor in which a regulating member for regulating horizontal movement of a float provided in a container containing liquid is provided, and the liquid level is detected by moving the float in the vertical direction. A liquid level sensor, wherein a locking float is provided between the regulating members so as to be movable up and down.   The restricting member includes a first restricting member provided in a horizontal cross section of the float and a second restricting member provided on an outer peripheral surface of the float, and the locking float is provided between the float and the second restricting member. 8. The liquid level sensor according to claim 7, wherein   9. The liquid level sensor according to claim 1, wherein the container containing the liquid is a container for storing a liquid used in a vehicle.

Images