JP2001194212A - Level detecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a level detecting device in which a terminal and an insulating board can be electrically connected with high reliability without using any solder. SOLUTION: The level detecting device is provided with the insulating board 8 in which a plurality of resistors 9 and connecting lands 13, 14 are provided on its surface. The detecting device is provided with a conductive segment group 11 which is connected to the plurality of resistors installed on the insulating board 8 at prescribed intervals. The detecting device is provided with a sliding plate 5 which is turned along the surface of the insulating board 8 due to a floating operation which is interlocked with a change in the surface of a liquid. The detecting device is provided with a sliding contact 6 which is installed at the sliding plate 5 and which comes into contact with the conductive segment group 11. The detecting device is provided with metal terminals 15, 16 by which the plurality of resistors 9 are connected to an external circuit. The terminals 15, 16 comprise contact pieces 15a which are connected electrically to the connecting lands 13, 14 and spring pieces 16b which come into contact with the contact pieces 15a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid level detecting device suitable for detecting a liquid level in a fuel tank of an automobile.

[0002]

2. Description of the Related Art A conventional liquid level detecting device is disclosed in
There was the one shown in 2-192223. This liquid level detecting device has a configuration in which a resistor is printed on an insulating substrate, and sliding contacts move in accordance with the movement of a float floating on the liquid surface in the fuel tank on the resistor, and A pair of resilient mounting pieces for holding the end of the insulating substrate are provided at the distal end of the connecting portion of the output extraction terminal connected to the resistor, and the connecting portion of the terminal is provided on the insulating substrate. It is soldered.

[0003]

However, in such a liquid level detecting device, a soldering step is required for soldering the connection between the terminal and the insulating substrate, so that the working efficiency is low and the cost is low. There was a problem of inviting the rise.

Accordingly, an object of the present invention is to provide a liquid level detecting device capable of electrically connecting a highly reliable terminal and an insulating substrate without using solder.

[0005]

According to the present invention, there is provided an insulating substrate provided with a resistor and a connection land on a surface thereof, and a plurality of conductive segments formed on the insulating substrate at predetermined intervals and connected to the resistor. A sliding plate that rotates along the surface of the insulating substrate with a float that is interlocked with a fluctuation in the liquid level; a sliding contact provided on the sliding plate and in contact with the conductive segment group; A metal terminal for connecting a body and an external circuit, the terminal being a contact piece electrically connected to the connection land, and a spring contacting the contact piece and pressing the contact piece toward the connection land side It has a piece.

Further, an insulating substrate having a resistor and a connection land on the surface thereof, a plurality of conductive segments formed on the insulating substrate at predetermined intervals and connected to the resistor, A sliding plate that moves along the surface of the insulating substrate with an associated float, a sliding contact provided on the sliding plate and in contact with the conductive segment group, and a metal that connects the resistor and an external circuit And a terminal made of
The terminal has a contact piece electrically connected to the connection land, and a holding piece for preventing the contact piece from moving in the opposite contact direction.

Further, the contact piece has a bent portion bent in the contact direction, and the holding piece comes into contact with the bent portion.

Further, the terminal has a groove for holding an end of the insulating substrate.

[0009] Further, the contact piece includes a plurality of contact portions for contacting the connection lands.

Further, fine projections are provided on the end surfaces of the contact pieces and / or the contact portions to contact the connection lands.

[0011] Further, there is provided a main body frame on which the insulating substrate is mounted, and the main body frame has a holding portion for holding the terminal.

[0012] Further, a retaining portion for retaining the terminal so as not to come off from the main body frame is provided in the retaining portion,
The terminal is provided with a stopper.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A liquid level detecting device 1 according to the present invention comprises an insulating substrate 8 having a resistor 9 and connection lands 13 and 14 on its surface, and a plurality of resistors 9 formed on the insulating substrate 8 at predetermined intervals. A conductive segment group 11 connected to the body 9, a sliding plate 5 rotating along the surface of the insulating substrate 8 with a float interlocking with a change in the liquid level, and a conductive segment provided on the sliding plate 5. A sliding contact 6 in contact with the group 11, metal terminals 15 and 16 for connecting the resistor 9 and an external circuit,
The terminals 15 and 16 have a contact piece 15a that is electrically connected to the connection lands 13 and 14, and a spring piece 15b that contacts the contact piece 15a and presses the contact piece 15a toward the connection lands 13 and 14. Without using a highly reliable terminal 15,
It is possible to provide the liquid level detecting device 1 capable of making an electrical connection between the insulating substrate 8 and the insulating substrate 8.

Since the terminals 15 and 16 have the grooves 15c for holding the ends of the insulating substrate 8, only the terminals 15 and 16 can be used without using other members.
It is possible to provide the liquid level detecting device 1 in which the liquid level detecting device 6 can be reliably connected to the connection land 13 at low cost.

The contact piece 15a is connected to the connection land 13,1.
By providing a plurality of contact portions 15g that come into contact with 4, the number of current supply paths to connection lands 13 and 14 becomes multiple, so that it is possible to provide liquid level detection device 1 with improved reliability of current supply.

Further, on the end face of the contact piece 15a and / or the contact portion 15g, a fine projection 15j that contacts the connection lands 13 and 14 is provided. With such a configuration, it is possible to provide the liquid level detection device 1 capable of shaving an insulator such as an oxide formed on the surface of the connection lands 13 and 14 and performing a good connection.

Further, the main body frame 4 for mounting the insulating substrate 8 is provided, and the main body frame 4 has an insertion hole 4b as a holding portion for holding the terminals 15 and 16, and the insulating substrate 8 and the terminals 15, 16 Is held by the main body frame 4, and the liquid level detecting device 1 capable of performing a reliable electric connection can be provided.

The terminal 1 is inserted into the insertion hole 4b as a holding portion.
An opening 4a is provided as a retaining portion for retaining the members 5 and 16 from the main body frame 4 so that the terminals 5 and 16 do not come off. The terminals 15 and 16 are provided with a retaining portion 15d. With this configuration, it is possible to provide the liquid level detection device 1 that can prevent the terminals 15 and 16 from falling off the main body frame 4.

Further, an insulating substrate 8 provided with a resistor 9 and connection lands 13 and 14 on its surface, and a conductive segment group 11 formed on the insulating substrate 8 at a plurality of intervals and connected to the resistor 9. A sliding plate 5 that moves along the surface of the insulating substrate 8 with a float interlocking with a change in the liquid level, sliding contacts 6 and 7 provided on the sliding plate 5 and contacting the conductive segment group 11, A metal terminal 19 for connecting the body 9 to an external circuit;
And a holding piece 19i for preventing the contact piece 19a from moving in the opposite contact direction. The terminal 19 and the insulating substrate 8 have high reliability without using solder. Can be provided.

The contact piece 19a is provided with a bent portion 19k bent in the contact direction.
9i is in contact with the liquid level detecting device 1, and the liquid pressure detecting device 1 can increase the contact pressure and provide a reliable electrical connection.

[0021]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 9 show a first embodiment of the present invention.

In FIG. 1 and FIG. 2, the liquid level detecting device 1 of the present invention is provided with a float (not shown) floating on the liquid level of fuel in a fuel tank (not shown) at the tip of a float arm 2. The arm holder 3 supports the float arm 2, the bent end 2 a of the float arm 2 is inserted into a through hole provided in the arm holder 3, and a pair of opposing pieces 3 a is formed on the upper part of the arm holder 3. And the opposing piece 3a
The float arm 2 is press-fitted into the arc surface while pushing and spreading the opposing piece 3a from the upper open portion therebetween, so that the float arm 2 does not come out upward due to the elastic restoring force of the opposing piece 3a.

The main body frame 4 on which the float arm 2 and the arm holder 3 are rotatably mounted has a bearing 4
e are integrally provided, and the floating arm 2 is
The bent end 2 a of the base end is inserted, and the arm holder 3 is rotatably held with respect to the main body frame 4. A sliding plate 5 made of a conductive metal is fixed to the arm holder 3, and the positional relationship between the float arm 2 and the sliding plate 5 is determined via the arm holder 3. A first sliding contact 6 made of a conductive metal and a second sliding contact 7 are provided on the sliding plate 5.

An insulating substrate 8 made of ceramic has an elastic piece 4c having a locking claw and a rod-shaped receiver 4d.
And is held in. On the surface of the insulating substrate 8, a resistor 9 extending in a strip shape and a conductive path 10 extending in a fan shape are formed.
And A conductive segment group 11 made of a conductive material is connected to the resistor 9. In the conductive segment group 11, the individual segments 11a are:
It is formed by forming a plurality of them at predetermined intervals.

The first and second sliding contacts 6 and 7 are always in contact with the conductive segment group 11 and the conductive path 10, respectively. Further, connection lands 13 and 14 are provided at one end of the resistor 9 and the conductive path 10, respectively.
14 are provided with terminals 15 and 16, respectively.
Lead wires 17 and 18 are connected to the terminals 15 and 16, respectively.
Thereby, a voltage change accompanying the rotation of the sliding plate 5 is output to a circuit (not shown) provided outside the fuel tank, and the like.
A not-shown instrument or the like is driven.

The terminals 15 and 16 have the same structure, and the terminal 15 shown in FIGS. 4 to 9 will be described as an example. Terminal 15
Is formed by subjecting a conductive plate-shaped metal to processing such as punching and bending. The terminal 15 has an elastic contact piece 15 a that comes into contact with the connection land 13. One end of the contact piece 15a is integrally connected to the terminal 15, and the contact portion near the tip of the other end is shown in FIG.
As shown in FIG. 7, the connection land 13 side (the lower side in FIG. 2)
In this structure, the contact portion 15g surely comes into contact with the connection land 13 at a contact portion 15g branched into two. In addition, fine projections 15j are provided on the end surfaces of the contact piece 15a and the contact portion 15g.
Is formed (see FIG. 9), and when it comes into contact with the connection land 13, an insulator such as an oxide formed on the surface of the connection land 13 is shaved and connected to the connection land 13.
A good connection can be made. Note that, when the terminal 15 is punched by a press, the fine protrusion 15j is punched from the upper side in FIG.
This is a burr formed on the end face of g. In the present embodiment, the projections 15j are formed on the end faces of the contact piece 15a and the contact portion 15g, but may be formed only on the contact portion 15g that contacts the connection land 13.

Further, in order to obtain a good electrical connection between the terminal 15 and the connection land 13, by removing an insulator such as an oxide formed on the surface of the connection land 13, a better connection can be obtained. An electrical connection can be obtained.

When the contact piece 15a comes into contact with the connection land 13, the contact piece 15a comes into contact with the terminal 15, the contact piece 15a bends, and the spring piece 15b presses the contact piece 15a toward the connection land 13.
It has. The spring piece 15b has a spring property in a wound shape. As described above, the tip of the contact piece 15a comes into contact with the spring piece 15b, and the spring piece 15b presses the contact piece 15a toward the connection land 13, so that the contact piece 15a is pressed by the spring piece 15b. 13, a high contact pressure can be obtained, and a decrease in the contact pressure due to a change with time can be prevented.

A groove 15 for inserting and holding an end of the insulating substrate 8 is provided on a side surface 15h located on both sides of the contact piece 15a.
c to position the insulating substrate 8 and
a is provided so as to securely connect to the connection land 13. Instead of providing the groove 15 c, although not shown, a portion for pressing the upper surface of the terminal 15 is provided in the main body frame 4, and the terminal 15 and the insulating substrate 8 are so contacted that the contact piece 15 a contacts the connection land 13. It is not necessary to provide the groove 15c as long as the positional relationship can be determined.

Reference numeral 15d denotes a stopper for preventing the terminal 15 from falling off from the main body frame 4. The stopper 15d is locked by an opening 4a, which is a retaining part provided on the main body frame 4, so that the terminal 15 connected to the insulating substrate 8 does not come off. It is to be. Also, 15
"e" is a first fixing portion for fixing the conductive wire portion of the lead wire 17 and electrically connecting to the terminal 15, and 15f is a first fixing portion.
7 is a second fixing portion for fixing the covering portion, and the first and second fixing portions
The fixing part is also deformed and fixed. With this configuration, the terminals 15 and 16 and the lead wires 17 and 18 can be electrically connected without using solder.

The connection between the terminal 15 and the insulating substrate 8 is completed only by mounting the insulating substrate 8 on the main body frame 4 in advance and inserting the terminal 15 into an insertion hole (holding portion) 4b provided in the main body frame 4. However, this makes it possible to easily connect without using solder, to reduce labor of work, and to provide an inexpensive liquid level detection device.

As described above, by providing the contact piece 15a and the spring piece 15b, the contact pressure between the connection land 13 and the contact piece 15a can be increased, so that the connection land 13 and the terminal can be reliably used without using solder. 15 can be electrically connected.

The groove 1 for holding the end of the insulating substrate 8
With the provision of 5c, the contact piece 15a can be securely connected to the connection land 13 without providing a portion for pressing the upper surface of the terminal 15 in the main body frame 4, and the shape of the main body frame 4 is not complicated. A reliable connection can be made at low cost.

Further, the terminal 15 can be prevented from coming off by engaging the stopper 15d with the opening 4a which is a stopper of the main body frame 4. The opening 4a serving as the retaining portion may have any shape as long as the retaining portion 15d of the terminal 15 is locked.

The contact piece 15a is connected to the connection land 13,1.
By providing a plurality of contact portions 15g that make contact with the connection member 4, there are provided a plurality of energization paths to the connection lands 13 and 14, so that it is possible to provide a liquid level detection device with improved energization reliability.

As described above, from the lead wire 17 to the terminal 15,
Connection land 13, resistor 9, conductive segment 11 group,
A circuit which is always electrically connected to the first sliding contact 6, the sliding plate 5, the second sliding contact 7, the conductive path 10, the connection land 14, the terminal 16, and the lead wire 18 is constituted. The first and second sliding contacts 6 and 7 are respectively slid and grounded on the conductive segment group 11 and the conductive path 10 at a predetermined contact pressure, and the first sliding contact 6 and the first resistor 9 A voltage change corresponding to a variable resistance with respect to the base end is output to detect a liquid amount.

As described above, since the liquid level detecting device can be assembled without using solder, an assembling operation is simple and a less expensive liquid level detecting device can be provided.

The shape of the terminal 15 is not limited to that of the first embodiment, and the shape of the terminal 15 shown in FIGS.
There are examples. The same and corresponding parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

The terminal 19 shown in FIGS. 10 to 13 is formed by punching or bending a conductive plate-shaped metal. The terminal 19 has an elastic contact piece 19 a that comes into contact with the connection land 13. One end of the contact piece 19a is integrally connected to the terminal 19, and as in the first embodiment, the contact portion near the tip of the other end protrudes toward the connection land 13 and has two ends. And the contact lands 13 are reliably contacted at two points.

The terminal 19 is provided with a holding piece 19i on a side face 19h to keep an appropriate contact pressure when the contact piece 19a comes into contact with the connection land 13. The holding piece 19i is in contact with the contact piece 19a to prevent the contact piece 19a from being excessively elastically deformed. This holding piece 19i
Is provided on the side surface 19h, and is provided above the intermediate portion of the contact piece 19a.

A bent portion 19k bent in the contact direction is formed at an intermediate portion of the contact piece 19a.
Since k is formed to be substantially the same height as the contact portion 19g, the contact pressure can be increased. Further, by holding the bent portion 19k with the holding piece 19i, a decrease in the contact pressure due to the elastic deformation of the contact piece 19a can be suppressed, the contact pressure can be maintained, and good contact can be maintained for a long time. it can.

As described above, the contact piece 19a becomes the holding piece 19i.
And the holding piece 19i holds the contact piece 19a, so that a high contact pressure can be obtained with respect to the connection land 13 and a decrease in the contact pressure due to aging can be prevented.

The side surface 19h is provided with a groove 19c for inserting and holding the end of the insulating substrate 8 as in the first embodiment, and the insulating substrate 8 is positioned so that the contact piece 19a is connected to the connection land 13. It is provided to ensure connection.
Although not shown, fine protrusions are formed on the end surfaces of the contact piece 19a and the contact portion 19g as in the first embodiment, and a good connection with the connection land 13 can be obtained. .

[0044]

As described above, according to the present invention, an initial object can be achieved, and a liquid level detecting device capable of performing highly reliable electrical connection between a terminal and an insulating substrate without using solder. Can be provided.

[Brief description of the drawings]

FIG. 1 is a top view of a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA in FIG.

FIG. 3 is a sectional view of an essential part taken along line BB in FIG. 1;

FIG. 4 is a top view of the terminal of the embodiment.

FIG. 5 is a side view of the embodiment.

FIG. 6 is a rear view of the embodiment.

FIG. 7 is a sectional view taken along line CC in FIG. 4;

FIG. 8 is a sectional view of a principal part taken along line DD in FIG. 5;

FIG. 9 is a sectional view taken along line EE in FIG. 7;

FIG. 10 is a top view of a terminal according to a second embodiment of the present invention.

FIG. 11 is a side view of the embodiment.

FIG. 12 is a rear view of the embodiment.

FIG. 13 is a sectional view taken along line FF in FIG. 10;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Liquid-level detection device 4 Main frame 4a Opening 4b Insertion hole (holding part) 5 Sliding plate 6 First sliding contact 7 Second sliding contact 8 Insulating substrate 9 Resistor 11 First conductive segment group 13 , 14 connection land 15, 16, 19 terminal 15a, 19a contact piece 15b spring piece 15c, 19c groove 15d, 19d retaining 15g, 19g contact part 15h, 19h side surface 15j projection 19i holding piece 19k bending part

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koichi Sato 2-2-234 Higashizao, Nagaoka-shi, Niigata F-term in Japan Seiki Co., Ltd. (reference) 2F013 AA04 BB03 CB01 3D038 CA15 CA31

Claims (8)

[Claims] An insulating substrate provided with a resistor and a connection land on a surface thereof; a plurality of conductive segments formed on the insulating substrate at predetermined intervals and connected to the resistor; A sliding plate that moves along the surface of the insulating substrate with an associated float, a sliding contact provided on the sliding plate and in contact with the conductive segment group, and a metal that connects the resistor and an external circuit And a contact piece that is electrically connected to the connection land, and a spring piece that contacts the contact piece and presses the contact piece toward the connection land. Surface detection device. 2. An insulating substrate having a resistor and a connection land on its surface, a plurality of conductive segments formed on the insulating substrate at predetermined intervals and connected to the resistor, and A sliding plate that moves along the surface of the insulating substrate with an associated float, a sliding contact provided on the sliding plate and in contact with the conductive segment group, and a metal that connects the resistor and an external circuit A liquid level detecting device, comprising: a contact piece that is electrically connected to the connection land; and a holding piece that prevents the contact piece from moving in a non-contact direction. . 3. The liquid level detecting device according to claim 2, wherein the contact piece has a bent portion bent in a contact direction, and the holding piece contacts the bent portion. 4. The terminal according to claim 1, wherein the terminal has a groove for holding an end of the insulating substrate.
The liquid level detecting device according to any one of the above. 5. The liquid level detecting device according to claim 1, wherein the contact piece includes a plurality of contact portions that contact the connection lands. 6. The fine contact according to claim 1, wherein a fine projection for contacting the connection land is provided on an end surface of the contact piece and / or the end face of the contact portion. Liquid level detector. 7. The liquid according to claim 1, further comprising a main body frame for mounting the insulating substrate, the main body frame including a holding portion for holding the terminal. Surface detection device. 8. The liquid level detecting device according to claim 7, wherein a retaining portion for retaining the terminal so that the terminal does not come off the main body frame is provided on the retaining portion, and the terminal is provided with a retaining portion. .