JP2018080951A - Liquid level detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid level detector which has high reliability of wiring, and which is excellent in productivity.SOLUTION: A liquid level detector includes: a holder 2 for rotating a circuit board in association with the movement of a float which moves by following a liquid level; terminals with elastic pieces including contacts which contact with an electrode part of the circuit board; a frame for storing a part of each terminal inside; and wires 6 electrically connected with the terminals. First protrusions 11E for restricting positions of the wires 6 are consecutively formed from the frame on a mounting surface for the wires 6 in the terminals.SELECTED DRAWING: Figure 2

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 holder that rotates the circuit board in accordance with the movement of the float that operates following the liquid level, a terminal that includes an elastic piece that includes a contact part that contacts the electrode part of the circuit board, In a liquid level detection device comprising a frame incorporating a part of the terminal, a wiring cord connected to the terminal is electrically connected by crimping, and the liquid level is detected by detecting a change in resistance value. Is.

JP 2014-139516 A

  However, since the attachment position of the end portion of the wiring cord is not specified, the location where the wiring cord is crimped becomes indefinite, and there is room for improvement in improving the connection reliability and production efficiency of the wiring.

  The present invention pays attention to the above-described problems, and provides a liquid level detection device with high wiring connection reliability and good productivity.

The liquid level detection device F of the present invention includes a holder 2 that rotates the circuit board 4 in accordance with the movement of the float FL that operates following the liquid level,
A terminal 5 having an elastic piece 5D provided with a contact 5A in contact with the electrode portion 4A of the circuit board 4;
A frame 1 containing a part of the terminal 5;
A wiring 6 electrically connected to the terminal 5;
With
The mounting surface 5E of the wiring 6 in the terminal 5 is provided with a first projecting portion 11E that regulates the position of the wiring 6 continuously from the frame 1.

  The first protruding portion 11E is provided with an inclined guide surface 11G that leads to the contact surface 11H with which the wiring 6 contacts.

  A second protrusion 11F is provided on the back surface 5F of the mounting surface 5E, and the terminal 5 is provided so as to be sandwiched between the first protrusion 11E and the second protrusion 11F.

  The liquid level detection device of the present invention has high wiring connection reliability and good productivity.

The perspective view of the liquid level detection apparatus of one Embodiment of this invention. The front view of the liquid level detection apparatus of the embodiment. The front view of the flame | frame of the embodiment. The rear view of the flame | frame of the embodiment. Sectional drawing of the principal part before crimping the terminal of the embodiment. The perspective view of the holder of the embodiment. The perspective view which looked at the holder of the embodiment from the back.

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

  As shown in FIGS. 1 and 2, the liquid level detection device F of the present invention includes a frame 1, a holder 2, a float arm 3, a circuit board 4, a terminal 5, a wiring cord (wiring) 6, And is used as a liquid level detecting device for detecting the liquid level of various liquids in a tank of an automobile, motorcycle or the like. Further, the liquid level detection device F is fixed to a fuel pump (not shown) made of synthetic resin or the like, an attachment stay, or the like.

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

  The base part 11 has three rectangular openings 11A, 11B, and 11C. Each opening 11 </ b> A, 11 </ b> B, 11 </ b> C penetrates the holder 2 in the rotation axis direction. In the first and second openings 11A and 11B, the crimped portion 5B of the terminal 5 is exposed, and in the third opening 11C, the contact 5A of the terminal 5 is exposed.

  First and second projecting portions 11E and 11F project from the wall surface 11D on the terminal 5 side of the first and second openings 11A and 11B, respectively. The contact surface 11H of the first protrusion 11E is a surface with which an end of a wiring cord 6 described later contacts. As shown in FIG. 5, the first protrusion 11 </ b> E is provided on the placement surface 5 </ b> E of the wiring cord 6 and includes a guide surface 11 </ b> G at the end. The 2nd protrusion part 11F is provided in the back surface 5F of a mounting surface. The first protrusion 11E and the second protrusion 11F are opposed to each other with the terminal 5 interposed therebetween. The first and second projecting portions 11 </ b> E and 11 </ b> F serve as reinforcing portions that prevent the terminal 5 from being deformed.

  The stopper 12 is composed of a first stopper 12A and a second stopper 12B. As shown in FIGS. 3 and 4, the rotation angle of the holder 2, that is, a float, is formed between the first and second stoppers 12A and 12B. The operating range of the arm 3 is defined.

  Three hook portions 13 are provided and are engaged with the fuel pump, the mounting stay, or the like.

  The bearing portion 14 is provided on the outer peripheral portion of the frame 1, and includes a through hole 14 </ b> A through which the shaft portion 3 </ b> A of the float arm 3 is inserted and rotatably supported, and the holder 2 is rotatably supported. .

  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 resin. As shown in FIGS. 6 and 7, the plate-shaped upper piece 2A, the lower piece 2B facing the upper piece 2A, the upper piece 2A, and the lower piece 2B. And 2C of connection parts which connect.

  The upper piece 2A includes a substrate housing portion 2A0 for arranging the circuit board 4, first and second engaging portions 2D1 and 2D2 for holding the float arm 3, and the float arm 3 having first and second engaging portions. A retaining portion 2D3 that prevents the portions 2D1 and 2D2 from coming off, a contact portion 2E that contacts the stopper 12 of the frame 1, and an insertion portion 2F that includes a through hole through which the shaft portion 3A of the float arm 3 is inserted. It is equipped with.

  The substrate housing portion 2A0 is disposed so that the electrode portion 4A formed on the circuit substrate 4 is exposed on the surface, and the outer peripheral portion of the circuit substrate 4 is fixed by the plurality of hook portions 2A1.

  The lower piece 2 </ b> B includes an insertion portion 2 </ b> B <b> 1 including a through hole through which the shaft portion 3 </ b> A of the float arm 3 is inserted.

  The connecting portion 2C connects the upper piece 2A and the lower piece 2B. The insertion part 2F of the upper piece 2A and the insertion part 2B1 of the lower piece 2B are connected.

  The bearing portion 14 of the frame 1 is sandwiched between the upper piece 2A and the lower piece 2B. The bearing portion 14 is sandwiched between the insertion portion 2F of the upper piece 2A and the insertion portion 2B1 of the lower piece 2B.

  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 FL is fixed to one end of the float arm 3. The float FL is made of NBR / phenol foam, floats on the liquid level of the fuel, etc., and operates following the liquid level. Further, a shaft portion 3A is provided at the other end. The shaft portion 3A passes through the through-hole 14A of the bearing portion 14 of the frame 1 and the two insertion portions 2F and 2B1 of the holder 2, so that the holder 2 is rotated about the shaft portion 3A of the float arm 3 as a rotation center. The frame 1 is supported so as to be rotatable.

  The circuit board 4 includes an electrode portion 4A, and a conductive material and a resistance material constituting the electrode portion 4A 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 includes an elastic piece 5D having a contact 5A that contacts the electrode part of the circuit board 4, a crimping part 5B that holds the wiring cord 6, a covering crimping part 5B1, an elastic piece 5D, and a crimping part. The relay unit 5C that connects the 5B is provided integrally.

  The elastic piece 5D includes a contact 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 a contact 5 </ b> A that is a tip portion thereof protrudes from a surface on the holder 2 side of the frame 1, and the contact 5 </ b> A is in contact with the circuit board 4.

  As shown in FIG. 3 to FIG. 5, the wiring cord 6 is composed of two wires, a ground wire and an output signal wire, and has a conducting wire portion 6 </ b> A and a covering portion 6 </ b> B, and is fixed to the terminal 5 by crimping.

  As a procedure for assembling the wiring cord 6 to the terminal 5, first, the wiring cord 6 is assembled so as to pass through the slit 11 </ b> I of the frame 1. At this time, the end portion of the wiring cord 6 is provided so as to abut against the contact surface 11H of the first protruding portion 11E provided on the mounting surface 5E side of the terminal 5. The slit 11I has a structure in which the wiring cord 6 is locked and is not easily removed. Further, even if the insertion amount of the wiring cord 6 into the frame 1 is too large and the end portion of the wiring cord 6 is lifted from the proper position, the wiring shown in FIG. The cord 6 can be led to an appropriate position. In this state, that is, at the position where the exposed wire portion 6A of the wiring cord 6 and the crimping portion 5B of the terminal 5 overlap, the crimping portion 5B can be deformed and crimped, and the terminal 5 and the wiring cord 6 are connected. The wiring cord 6 can be held on the mounting surface 5E of the terminal 5 while being in an electrically conductive state. In addition, the covering crimping portion 5B1 can be crimped at an appropriate position while deforming the covering portion 6B of the wiring cord 6, and a desired retaining strength of the wiring cord 6 can be obtained. It becomes.

  By providing the first protrusion 11E, the contact surface 11H of the wiring cord 6 can be defined. Therefore, since the end position of the wiring cord 6 can be defined, the crimping position can be made constant, and the connection reliability between the terminal 5 and the wiring cord 6 can be improved.

  By providing the guide surface 11G, the wiring cord 6 can be guided to the contact surface 11H, so that the wiring cord assembly work is facilitated, and automation of the assembly work can be expected.

  By providing the second protrusion 11F, the terminal 5 can be fixed by the first and second protrusions 11E and 11F, and deformation of the terminal 5 can be suppressed. It can be expected to further improve the connection reliability.

  Therefore, it is possible to provide a liquid level detection device with high connection reliability of the wiring cord and good productivity.

  The above description exemplifies the present invention, and it goes without saying that various changes and modifications can be made without departing from the scope of the invention.

  In the above-described embodiment, the case where the wiring cord 6 is attached from the surface on the side where the holder 2 of the frame 1 is attached is illustrated, but the same effect can be expected as a structure where the wiring cord 6 is attached from the opposite surface.

  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 FL Float 1 Frame 2 Holder 2A Upper piece 2A0 Substrate storage part 2A1 Hook part 2B Lower piece 2B1 Insertion part 2C Connection part 3 Float arm 3A Shaft part 4 Circuit board 4A Electrode part 5 Terminal 5A Contact point 5B Clamping part 5B1 Covering caulking portion 5C Relay portion 5D Elastic piece 5E Placement surface 5F Back surface 6 Wiring 6A Conducting portion 6B Covering portion 11 Base portion 11A First opening portion 11B Second opening portion 11C Third opening portion 11D Wall surface 11E First protruding portion 11F 2nd protrusion part 11G Guide surface 11H Contact surface 11I Slit 12 Stopper 12A 1st stopper 12B 2nd stopper 13 Hook part 14 Bearing part 14A Protrusion part

Claims (3)

A holder that rotates the circuit board in accordance with the movement of the float that follows the liquid surface;
A terminal having an elastic piece with a contact point in contact with the electrode part of the circuit board;
A frame containing a part of the terminal;
Wiring electrically connected to the terminals;
In a liquid level detection device comprising:
On the placement surface of the wiring in the terminal, a first protrusion that regulates the wiring position,
A liquid level detection device provided continuously from the frame. The liquid level detection device according to claim 1, wherein the first projecting portion is provided with an inclined guide surface that leads to a contact surface that contacts the wiring. A second protrusion is provided on the back surface of the placement surface,
The liquid level detection device according to claim 1, wherein the terminal is provided so as to be sandwiched between the first protrusion and the second protrusion.

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