JP5995118B2 - Liquid level detector - Google Patents

Description

  The present invention relates to a liquid level detection device for detecting the level of fuel in a fuel tank of an automobile.

  A conventional liquid level detection device is disclosed in Patent Document 1, for example. The liquid level detection device includes a float arm having a float that floats on the liquid level, an arm holder that holds the float arm and moves as the float arm rotates, and a frame that rotatably supports the arm holder. In the liquid level detecting device, a bearing portion made of a through hole is provided in the frame, a shaft portion to be inserted into the bearing portion is provided in the arm holder, and an elastically deformable locking piece having a locking claw is provided in the shaft portion. The shaft portion is inserted into the bearing portion, locked to the engaging portion of the bearing portion with a locking claw, and the arm holder is rotatably supported on the frame.

JP 2005-241553 A

  However, in the conventional liquid level detection device, the member that rotatably supports the holder on the frame is merely a locking claw provided on the arm holder, and is only locked to the engaging portion of the bearing portion of the frame. It has been desired to firmly support the holder on the frame so as to be rotatable.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a liquid level detection device that solves the above-mentioned problems and supports a holder firmly and rotatably on a frame.

The liquid level detection device of the present invention is
Includes a circuit board housing portion for fixing the circuit board, and the holder for rotating the circuit board with the movement of the float which operates to follow the liquid surface,
In a liquid level detection apparatus comprising: a terminal having an elastic piece provided with a contact portion that contacts an electrode portion of the circuit board; and a frame containing a part of the terminal.
The outer peripheral portion of the frame includes a bearing portion that rotatably supports an end portion of the float arm held by the holder,
The holder has a U-shaped holding portion having two pieces arranged between the bearing portions, and
A recess-shaped guide part formed by being surrounded by the holding part and a wall around the circuit board is provided at a place where the holding part and the bearing part come into contact with each other. To do.

Further, the bearing portion of the frame is formed with a protruding portion that faces the recess,
The holder includes a wall formed around the protruding portion and a guide portion for attaching and guiding the protruding portion.

Moreover, a through hole through which the float arm is passed is formed in the holding portion of the holder,
The wall restricts the position of the bearing portion so that the through hole of the holding portion and the through hole of the bearing portion overlap each other.

  The present invention can provide a liquid level detection device that supports a holder firmly and rotatably on a frame.

The perspective view of the liquid level detection apparatus of 1st Embodiment of this invention. The rear view of the liquid level detection apparatus of the embodiment. The perspective view of the holder of the embodiment. The perspective view of the holder of the embodiment. The side view of the terminal and wiring cord of the embodiment. The rear view of the terminal and wiring cord of the embodiment. The perspective view of the flame | frame and wiring cord of the embodiment. The principal part perspective view of the attaching part of the embodiment. The perspective view of the flame | frame and holder of the embodiment. The perspective view of the flame | frame and holder of the embodiment. The perspective view of the liquid level detection apparatus of the embodiment. The top view of the liquid level detection apparatus of the embodiment. Sectional drawing of the liquid level detection apparatus of the AA line in FIG.

  Hereinafter, a first embodiment of the present invention will be described with reference to the accompanying drawings.

  The liquid level detection device F according to the embodiment of the present invention mainly includes a frame 1, a holder 2, a float arm 3, a circuit board 4, and terminals 5. A wiring cord 6 is fixed to the terminal 5. The liquid level detection device F is fixed to a mounting portion 7 made of a synthetic resin such as a fuel pump or a mounting stay.

  The frame 1 is made of synthetic resin, for example, polyacetal, and integrally includes a base portion 11, a stopper portion 12, a hook portion 13, and a bearing portion 14. Further, a part of the terminal 5 is built in the frame 1 by insert molding.

  The base portion 11 has four rectangular first to fourth openings 1A to 1D opened in the direction of the rotation axis S of the holder 2 (vertical direction in FIG. 13), and the first opening 1A and 3rd opening part 1C, 2nd opening part 1B, and 4th opening part 1D are provided in one set along the two each terminals 5. FIG. In the first and third openings 1A and 1C, an elastic piece 5D provided with a contact portion 5A of the terminal 5 described later is exposed, and is used when forming the contact portion 5A of the terminal 5 and the elastic piece 5D. The second and fourth openings 1 </ b> B and 1 </ b> D have a caulking portion 5 </ b> B of the terminal 5 to be described later exposed, and are used during caulking work of the caulking portion 5 </ b> B.

  The second and fourth openings 1 </ b> B and 1 </ b> D are formed by a protective wall 15 formed integrally with the frame 1, and protect the crimped portion 5 </ b> B of the terminal 5. The protective wall 15 is provided with a slit as a cord lead-out portion 16 that pulls out the wiring cord 6 to the outside of the protective wall 15. The cord lead-out portion 16 may be a through hole.

  Further, a slide guide 1A1 into which a positioning portion 7B of the mounting portion 7 described later is inserted is provided on the mounting portion 7 side of the first opening 1A. This slide guide 1A1 has a T shape like the positioning portion 7B, and is formed slightly larger than the positioning portion 7B so that the positioning portion 7B is inserted.

  The stopper portion 12 regulates the rotation of the holder 2 and includes a first stopper portion 12A and a second stopper portion 12B. The first stopper portion 12A is formed so as to protrude from the side surface of the base portion 11 on the side opposite to the direction in which the wiring cord 6 is pulled out, and the shape viewed from the upper surface is a substantially triangular shape. The second stopper portion 12B is formed to extend from the side surface of the base portion 11 on the opposite side to the bearing portion 14, and has a substantially triangular shape when viewed from the upper surface.

  The first and second stopper portions 12A and 12B are protruding convex portions. The thickness of the convex portion of the holder 2 in the direction of the rotational axis S is thinner than the thickness of the side surface of the frame 1 in the direction of the rotational axis S. The thicknesses of the first and second stopper portions 12A and 12B are set to about ½ of the thickness of the side surface of the frame 1. By comprising in this way, distortion of 1st, 2nd stopper part 12A, 12B by shaping | molding can be suppressed, and favorable flatness can be ensured.

  As described above, the rotation angle of the holder 2, that is, the operating range of the float arm 3 is defined by the first and second stopper portions 12A and 12B. Moreover, the precision of the rotation angle of the holder 2 is securable by making the stopper parts 12A and 12B into convex parts.

  Further, in the vicinity of the first and second stopper portions 12A and 12B, separation prevention walls 12A2 and 12B2 for preventing the holder 2 from rotating beyond the first and second stopper portions 12A and 12B are provided. ing. The separation preventing walls 12A2 and 12B2 are provided at positions outside the holder 2 with the rotation axis S of the holder 2 as the center.

  The hook portion 13 includes a locking portion 13A and an elastic piece 13B. The elastic piece 13B is elastically deformable, protrudes to the side opposite to the second stopper portion 12B of the base portion 11, and tightens the terminal 5 It is formed so as to extend toward the part 5B side and substantially parallel to the attachment surface of the attachment part 7. A locking portion 13A is provided at the tip of the elastic piece 13B. The locking portion 13 </ b> A engages with an engaging portion 7 </ b> A provided on the attachment portion 7, and the frame 1 is fixed to the attachment portion 7.

  In order to fix the frame 1 to the attachment portion 7, the positioning portion 7B of the attachment portion 7 is inserted into the slide guide 1A1, and the frame 1 is moved along the attachment surface of the attachment portion 7 in the direction of arrow C shown in FIG. Fixing is completed by locking the locking portion 13A to the engaging portion 7A. In addition, 7C of FIG. 1 is a 2nd positioning part, and it followed the attachment surface of the attachment part 7 with respect to the moving direction at the time of fixing to the attachment part 7 of the flame | frame 1 (arrow C direction in FIG. 1). The position in the vertical direction is regulated.

  The bearing portion 14 is provided on the outer peripheral portion of the frame 1 and supports the holder 2 so as to be rotatable. The bearing portion 14 includes a through hole 14 </ b> A through which an end portion of the float arm 3 is inserted.

  Moreover, the bearing part 14 is provided with the protrusion part 14B which protruded in the holder 2 side in the rotation axis S direction. The protrusion 14B serves as a guide when the holder 2 is attached to the frame 1.

  Further, the frame 1 includes a first guide part 17 and a second guide part 18. The first guide portion 17 is a groove in which a lower piece (piece) of a holding portion, which will be described later, of the holder 2 can move in the direction of the rotation axis S of the holder 2. The first guide portion 17 is recessed to a position closer to the inner side of the frame 1 than the through hole 14A of the bearing portion 14, in other words, in a direction perpendicular to the longitudinal direction of the terminal 5 and the rotation axis S direction. The second guide portion 18 is a groove in which a lower piece of a holding portion (to be described later) of the holder 2 can move in the longitudinal direction of the terminal 5 in a direction perpendicular to the rotation axis S direction of the holder 2. The second guide portion 18 is recessed to a position closer to the inside of the frame 1 than the through hole 14A of the bearing portion 14, in other words, in a direction perpendicular to the longitudinal direction of the terminal 5 and the rotation axis S direction, The second guide portion 18 is provided with a through hole 14 </ b> A on the mounting portion 7 side of the bearing portion 14. The 2nd guide part 18 and the 1st guide part 17 are connected.

  The two holes 11A provided in the base portion 11 are formed by pins for positioning the terminals 5 when the terminals 5 are insert-molded in the frame 1, and the holes 11B provided in the intermediate positions of the holes 11A 1 is provided to cut the connecting portion of the terminal 5 which was integrated by a connecting portion (not shown) at the time of molding. A tool for cutting is inserted into the hole 11B, and the terminal 5 is divided.

  The holder 2 rotates the circuit board 4 in accordance with the movement of the float that operates following the liquid level. The holder 2 is made of synthetic resin, for example, polyacetal, and has a plate-like circuit board housing portion 2A for placing the circuit board 4 and a U-shaped holding portion 2B for placing the bearing portion 14 of the frame 1 therebetween. The first and second engaging portions 2C1 and 2C2 that hold the float arm 3 and the hanging portion 2E having the contact surface 2D that contacts the stopper portion 12 of the frame 1 are provided.

  The circuit board housing part 2A is arranged so that an electrode part (not shown) formed on the circuit board 4 is exposed on the surface, and the outer peripheral part of the circuit board 4 is fixed by a plurality of hook parts 2A1 in the housing part 2A.

  The holding portion 2B includes a circuit board housing portion (piece) 2A that also serves as an upper piece and a lower piece 2B2, and the bearing portion 14 is disposed between the circuit board housing portion 2A and the lower piece 2B2. The circuit board housing portion 2A and the lower piece 2B2 are provided with through holes 2A2 and 2B3, respectively. The end of the float arm 3 is inserted into the through holes 2A2 and 2B3. By inserting the float arm 3 into the through holes 14A, 2A2, and 2B3 of the frame 1 and the holder 2, the float arm 3 passes through the through holes 14A and the through holes 2A2 and 2B3, and the holder 2 is a bearing portion of the frame 1. 14, the holder 2 is disposed so as to be rotatable with respect to the frame 1 with the end of the float arm 3 as the rotation center.

  The first locking portion 2C1 and the second locking portion 2C2 are provided on the surface of the circuit board housing portion 2A of the holder portion 2.

  The first locking portion 2 </ b> C <b> 1 is provided in the center portion of the surface of the holder 2, and has a C shape with an opening 2 </ b> C <b> 3 opened in a direction perpendicular to the rotation axis S direction of the holder 2. The float arm 3 can be fitted from the horizontal direction along the surface of the holder 2.

  The second locking portion 2C2 is a retainer that prevents the float arm 3 from being detached from the first locking portion 2C1 after the float arm 3 is attached to the first locking portion 2C1, and the holder 2 is rotated. The configuration is elastically deformable in the axis S direction. Therefore, when the float arm 3 is fitted into the first locking portion 2C1, the second locking portion 2C2 is deformed to the circuit board 4 side so that the float arm 3 can be guided to the first locking portion 2C1. After the arm 3 is fixed to the first locking portion 2C1, the second locking portion 2C2 returns to the original position, so that the float arm 3 does not come off from the first locking portion 2C1.

  The hanging part 2E extends in the direction of the rotation axis S of the holder 2 along the side surface of the frame 1 when the holder 2 is attached to the frame 1. The hanging portion 2E is provided as an L-shaped wall portion perpendicular to the corner portion of the circuit board housing portion 2A of the holder 2, which is the farthest position from the rotation center of the holder 2.

  The contact surface 2D is an end surface of the hanging portion 2E that extends in the direction of the rotation axis S of the holder 2, and is in contact with the first and second stopper portions 12A and 12B of the frame 1, respectively. The angle at which the contact surface 2D contacts the first and second stopper portions 12A and 12B is an angle substantially orthogonal to the surfaces of the convex portions 12A1 and 12B1 of the first and second stopper portions 12A and 12B. It is.

  A third guide portion (guide portion) 2 </ b> F that guides the protruding portion 14 </ b> B of the bearing portion 14 of the frame 1 is provided on the side of the holder 2 where the circuit board storage portion 2 </ b> A is stored. The third guide portion 2F is a recess formed by the wall 2G, the wall 2H, and the holding portion 2B around the circuit board 4. In FIG. 4, the wall 2H provided on the outer periphery of the holder 2 regulates the movement of the protrusion 14B when the holder 2 is attached to the frame 1, and the through hole 14A of the frame 1 and the through hole 2A2 of the holder 2 2B3 is arranged on substantially the same straight line, and the float arm 3 makes it easy to pass through the through holes 14A, 2A2, and 2B3.

  The float arm 3 is made of a hard steel wire, and is bent into a predetermined shape so as to be attached to the holder 2 or matched to the fuel tank shape. A float (not shown) is fixed to the float arm 3. This float is made of NBR / phenol foam, and floats on the liquid level of fuel or the like, and operates following the liquid level.

  The circuit board 4 includes an electrode portion (not shown), and a conductor material and a resistance material constituting the electrode portion are formed on the insulating substrate by printing and baking. The circuit board 4 is attached to the holder 2 and interlocks with a float that operates following the liquid level.

  The terminal 5 is made of, for example, a white material, and two terminals 5 are provided. Each terminal 5 has an elastic piece 5D provided with a contact part 5A that contacts the electrode part of the circuit board 4, a crimping part 5B that holds the wiring cord 6, and a relay that connects the elastic piece 5D and the crimping part 5B. The unit 5C is integrally provided.

  The elastic piece 5D includes a contact portion 5A made of, for example, an alloy of palladium and nickel, which contacts the electrode portion of the circuit board 4 and slides on the electrode portion at the tip portion. The elastic piece 5 </ b> D is formed such that the contact portion 5 </ b> A, which is the tip, protrudes from the surface of the frame 1 on the holder 2 side, and the contact portion 5 </ b> A is in contact with the circuit board 4.

  The caulking portion 5B includes a pair of first arm pieces 5B1 for holding the core wire 6A of the wiring cord 6 and a pair of second arm pieces 5B2 for holding the covering portion 6B of the wiring cord 6. The pieces 5B1 and 5B2 are also firmly crimped by the crimping jig to hold the wiring cord 6. And this arm piece 5B1, 5B2 has faced the attachment part 7 direction. Since the terminal 5 is disposed on the holder 2 side of the frame 1, the positioning portion 7 </ b> B of the mounting portion 7 can be accommodated in the frame 1, and the terminal 5 is disposed on the holder 2 side of the frame 1. Accordingly, the caulking portion 5B is also disposed on the holder 2 side of the frame 1, and a space is provided between the caulking portion 5B and the mounting portion 7 side of the frame 1 in the second opening portion 1B and the fourth opening portion 1D. The arm pieces 5B1 and 5B2 that are formed and faced in the direction of the attaching portion 7 before being caulked in this space can be stored, and the arm pieces before caulking at the time of flow in the manufacturing process of the liquid level detection device F The deformation of 5B1 and 5B2 can be suppressed.

  The relay part 5C connects the elastic piece 5D and the caulking part 5B, and a part of the relay part 5C is built in the frame 1. The relay part 5C includes a reinforcing part 5C1 extending from the caulking part 5B. The reinforcing portion 5C1 has a U-shaped cross section including a wall formed by bending both ends of the relay portion 5C. By providing this reinforcing portion 5C1, the holding force in insert molding is improved, and the bending strength of the terminal 5 itself is improved.

  The distance between the elastic pieces 5D is narrower than the distance between the crimping portions 5B of the two terminals 5. This is because the electrodes of the circuit board 4 are reduced in size by narrowing the interval between the elastic pieces 5D, and consequently the circuit board 4 is reduced in size. For this reason, one terminal 5 has a shape in which the elastic piece 5D and the caulking portion 5B are offset without being positioned on a straight line.

  The relay portion 5 </ b> C includes a hole portion 5 </ b> C <b> 3 in which a positioning pin (not shown) when the terminal 5 is inserted into the frame 1 is fitted. The hole 5C3 is provided on an extension line of the elastic piece 5D of each terminal 5. By configuring in this way, compared to the case where the position where the hole 5C3 is provided differs for each terminal 5, when the elastic piece 5D is formed, variation due to bending of the elastic piece 5D is suppressed, and the contact of the contact portion 5A It becomes possible to arrange the load.

  The wiring cord 6 is composed of two wires, a ground wire and an output signal wire, and a metal core wire 6A such as copper is covered with an oil-resistant cross-linked polyethylene covering portion 6B, and is fixed to the terminal 5 by caulking. The

  A method for attaching the holder 2 to the frame 1 will be described with reference to FIGS.

  The longitudinal direction of the circuit board 4 and the longitudinal direction of the elastic piece 5D of the terminal 5 are matched to each other, and the first guide portion formed on the frame 1 by the lower piece 2B2 of the holding portion 2B of the holder 2 from the position shown in FIG. 17 is moved toward the frame 1 side. At this time, the contact portion 5 </ b> A of the terminal 5 contacts the circuit board 4, and the protruding portion 14 </ b> B of the bearing portion 14 contacts the third guide portion 2 </ b> F of the holder 2.

  Next, when the holder 2 is moved to the position shown in FIG. 10, the lower piece 2 </ b> B <b> 2 of the holding part 2 </ b> B is moved along the second guide part 18 of the frame 1, and the contact part 5 </ b> A becomes an electrode part (not shown) of the circuit board 4. Contact.

  Then, the through holes 14A, 2A2, and 2B3 of the frame 1 and the holder 2 are aligned, and the end of the float arm 3 is inserted into the through holes 14A and the through holes 2A2 and 2B3. The float arm 3 is rotated about the end of the float arm 3 as an axis, and the float arm 3 is fixed by the first locking portion 2C1 and the second locking portion 2C2, and the holder 2 is attached to the frame 1. Complete.

  As described above, it is possible to provide a liquid level detection device that supports the holder firmly and rotatably on the frame.

  The present invention is applicable to a liquid level detection device that detects the liquid level of various liquids in a tank.

F Liquid level detection device S Rotating shaft 1 Frame 1A 1st opening 1A1 Slide guide 1B 2nd opening 1C 3rd opening 1D 4th opening 2 Holder 2A Circuit board storage part (piece)
2A1 Hook part 2A2 Through hole 2B Holding part 2B2 Lower piece
2B3 Through-hole 2C1 1st latching | locking part 2C2 2nd latching | locking part 2D Contact surface 2E Hanging part 2F 3rd guide part (guide part)
2G wall 2H wall 3 float arm 4 circuit board 5 terminal 5A contact part 5B crimping part 5B1 first arm piece 5B2 second arm piece 5C relay part 5C1 reinforcing part 5C3 hole part 5D elastic piece 6 wiring cord 6A core wire 6B covering part 7 Mounting portion 7A Engaging portion 7B Positioning portion 7C Second positioning portion 11 Base portion 11A Hole 11B Hole 12 Stopper portion 12A First stopper portion 12B Second stopper portion 12A2, 12B2 Detachment prevention wall 13 Hook portion 13A Locking portion 13B Elastic piece DESCRIPTION OF SYMBOLS 14 Bearing part 14A Through-hole 14B Protrusion part 15 Protection wall 16 Cord extraction part 17 1st guide part 18 2nd guide part

Claims (3)

Includes a circuit board housing portion for fixing the circuit board, and the holder for rotating the circuit board with the movement of the float which operates to follow the liquid surface,
In a liquid level detection apparatus comprising: a terminal having an elastic piece provided with a contact portion that contacts an electrode portion of the circuit board; and a frame containing a part of the terminal.
The outer peripheral portion of the frame includes a bearing portion that rotatably supports an end portion of the float arm held by the holder,
The holder has a U-shaped holding portion having two pieces arranged between the bearing portions, and
A recess-shaped guide part formed by being surrounded by the holding part and a wall around the circuit board is provided at a place where the holding part and the bearing part come into contact with each other. Liquid level detection device. The bearing portion of the frame is formed with a protruding portion facing the recess,
The liquid level detection device according to claim 1, wherein the holder includes a wall formed around the protruding portion and a guide portion for attaching and guiding the protruding portion. A through hole through which the float arm passes is formed in the holding portion of the holder,
The liquid level detection device according to claim 2, wherein the wall restricts the position of the bearing portion so that the through hole of the holding portion and the through hole of the bearing portion overlap each other. .

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