JPH0733169Y2 - Bimetal type instrument - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a bimetal type instrument applied to an auxiliary instrument such as a fuel gauge and a water temperature gauge mounted on a vehicle instrument.

[Conventional technology]

Conventionally, as a bimetal type instrument of this kind, for example,
As disclosed in Japanese Patent No. 34129, Japanese Utility Model Laid-Open No. 60-159315, etc., a pointer shaft is rotatably supported by a holder via a bearing, and the pointer is press-fitted and fixed to the tip of the pointer shaft. At the same time, a lever provided with a slit is press-fitted and fixed in the middle thereof. Also, the free end side of the temperature compensating leg portion of the substantially U-shaped bimetal is fixed to the holder, the heat wire is wound around the movable leg portion of the bimetal, and the free end portion of the bimetal movable leg portion is wound. The base end side of the pin is welded and fixed in parallel with the pointer shaft by spot welding means, and the tip end of the pin is slidably inserted and engaged with a slit provided in the lever. Then, the movable leg of the bimetal is bent by the amount of heat according to the amount of current flowing through the heating wire, and the pin provided on the movable leg is used to rotate the lever, thereby rotating the pointer shaft that is linked to the lever. There has been proposed a structure in which the pointer provided at the tip of the pointer shaft and the display portion of the display plate are compared to read the displayed value.

[Problems to be solved by the device]

In the bimetal type instrument having the above structure, the pointer pointing region is determined by the bimetal bending motion, that is, the amount of lateral displacement. Then, when the pointing area of the pointer is widened in consideration of visibility, the displacement amount of the tip of the movable leg can be widened by forming the movable leg of the bimetal to be long, The deflection angle of the pointer that rotates via the pin provided on the tip side of the movable leg also becomes a wide angle, and the pointing area can be widened. However, in recent years, a vehicle instrument equipped with this type of instrument tends to be downsized due to market needs. Therefore, if the bimetal is formed to be long, a large mounting space is required, and therefore the entire instrument is downsized. There is a downside to it.

Therefore, in order to reduce the installation space of the bimetal and to widen the pointing area of the pointer, as shown in FIG. 6, the pin 3 and the pointer shaft 4 provided on the tip side of the movable leg portion 2 of the bimetal 1 are provided. By attaching the bimetal 1 so as to narrow the distance S between and as much as possible, the deflection angle of the lever 5 increases, so that the pointing area of the pointer 5 can be widened.

By the way, the pin 3 is welded and fixed by spot welding along a direction substantially parallel to the pointer shaft 4 on the tip end side of the movable leg portion 2 of the bimetal 1. However, during this spot welding, burrs A may occur at the welded portions of the pin 3, and since the burrs A normally project in the direction orthogonal to the pin 3, they overhang to the pointer shaft 4 side, and as described above. When attempting to downsize the entire instrument, there was a problem that the burr A was caught by the pointer shaft 4 during the bending operation of the bimetal 1, the movable leg 2 was not displaced accurately, and the pointer 5 was adversely affected. . Therefore, after the spot welding of the bimetal 1 and the pin 3, it is necessary to perform a post-treatment such as scraping off the burr A, which requires a troublesome labor and time, and the work efficiency is poor.

The present invention has been made based on the above problems, and it is possible to reduce the size of the instrument and prevent the influence of the miniaturization on the indicator characteristic of the pointer to keep the pointer instruction in a stable state. The purpose is to provide a bimetal instrument that can be used.

[Means for Solving the Problems]

According to the present invention, a pointer shaft is supported on a holder, and a substantially U-shaped bimetal consisting of a movable leg part for winding a heat wire and a temperature compensating part is attached and fixed to the holder, and a slit is provided on the pointer shaft. A lever is fixed, and a pin that engages with the slit is fixed to the free end side of the movable leg, and the bimetal is bent with a heat amount according to the amount of current flowing through the heating wire, and the lever is inserted through the lever. In a bimetal type instrument for operating the pointer shaft in a linked manner according to the displacement of the bimetal and rotating and displaying a pointer provided on the pointer shaft, a fixing portion formed on the pin so as to extend in a direction crossing the pointer shaft. And the fixed portion is welded and fixed to the movable leg portion.

[Action]

By fixing the fixing part of the pin that extends in the direction intersecting the pointer shaft on the free end side of the bimetal by welding, the burr that protrudes in the direction orthogonal to the pin during welding moves away from the pointer shaft.
There is no interference between the burr and the pointer axis.

〔Example〕

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

1 to 3 show an embodiment of the present invention, in which reference numeral 11 is a case (holder) having a front opening, and a bottom wall 11A of the case 11 has a bearing 12 and a pointer shaft. The lower end of 13 is pivotally supported, and the upper end of the pointer shaft 13 is rotatably supported by being inserted into a small hole 15 provided in a plate 14 installed on the front surface of the case 11. A pointer shaft 16 is press-fitted into the upper end portion of the pointer shaft 13, and a synthetic resin lever 17 is press-fitted and fixed in the middle thereof, and a slit 18 is formed in the lever 17.
Are formed.

Reference numeral 19 is a U-shaped bimetal having a temperature compensating leg portion 20 and a movable leg portion 21, and the free end side of the temperature compensating leg portion 20 is fixed to a finger pointing plate 22 provided on the bottom wall 11A of the case 11. Is
A heat wire 23 is wound around the movable leg portion 21,
A metallic pin 24 is welded and fixed to the free end by spot welding. The pin 24 is bent in the shape of an inverted L, and the fixed portion 24A on the base end side, which is a welded portion with the movable leg portion 21, intersects with the pointer shaft 13 in the orthogonal direction, in the present embodiment. Spot welded and this pin
The tip end side of 24 is directed downward so as to be parallel to the pointer shaft 13, and slidably inserted and engaged with a slit 18 provided in the lever 17. An insulating substrate 25 made of synthetic resin is caulked and fixed to the outer surface side of the bottom 11A of the case 11, and an L-shaped terminal 26 having a screw hole 26A is embedded in the substrate 25, and the tip side thereof is The bottom end 11A is inserted into the case 11 through a notch hole 27 formed in the bottom part 11A, and the end of the heating wire 23 is connected to the tip of the terminal 26. Also, the case
11 is stored and fixed in the instrument case 28, and the case 11
A dial plate 29 is provided on the front side of the dial plate 13. The pointer shaft 13 is projected from the dial plate 29, and the pointer 16 is press-fitted and fixed to the tip end portion of the pointer shaft 13. Further, in the figure, 30 is a flexible printed board (FPC board) arranged along the outer surface of the bottom of the instrument case 28, 31 is a screw, and this screw 31 is an insertion hole provided in the instrument case 28 and the FPC board 30. The FPC plate 30 and the bimetal type instrument are electrically connected to each other by being screwed to the screw portion 26A of the terminal 26 via 32, and the case 11 and the instrument case 28 are fixed to each other.

The bimetal type instrument configured as described above, for example, energizes the heating wire 23 with a current proportional to the resistance change of the water temperature sensor (not shown) that changes depending on the cooling water temperature to cause the heating wire 23 to generate heat, and the heat quantity of the heating wire 23. In response to the bimetal 19, the movable leg portion 21 is bent to rotate the pointer shaft 13 via the lever 17 that is linked to the pin 24 provided on the movable leg portion 21 and integrated with the pointer shaft 13. Pointer 30 and dial that rotate to
The display value is read by comparing with a display unit (not shown) provided on the front surface of 29. In this case, since the deflection angle of the pointer 30 is wide and the pointing area is wide,
The gap S with the pin 14 is set to about 0.5 mm.

As described above, in the present invention, the gap S between the pointer shaft 13 and the pin 14 is set narrow, but the base end side where the pin 14 is welded is orthogonal to the pointer shaft 13 on the tip side of the movable leg 21. Since it is welded and fixed in the direction, even if a burr A protruding in a direction orthogonal to the pin 14 occurs during spot welding of the pin 14, the burr A is formed so as to extend substantially parallel to the pointer shaft 13. As in the above-mentioned conventional example, the pointer shaft is extended to the pointer shaft 13 side.
There is no concern that it will be caught by 13 and adversely affect the instruction of the pointer 30, and the instruction can be kept in good condition.

The present invention is not limited to the above-mentioned embodiment,
Various modifications are possible within the scope of the present invention,
For example, in the above-described embodiment, the inverted L-shaped pin 24 is inserted and engaged in the slit 18 provided in the lever 17 with the tip end side facing downward, but as shown in FIG. On the contrary, the tip end side of the L-shaped pin 24 may be inserted and engaged in the slit 18 of the lever 17 with the tip end side facing upward. Although the pin 24 is formed in a substantially L shape so as to be substantially orthogonal to 13, the extension is not limited to this, and the extension line of the base end portion of the pin 24 and the pointer shaft 13 as shown in FIG. An inclined fixing portion 24B is extended and formed on the base end portion of the pin 24 so as to intersect with each other.
May be fixed to the movable leg portion 21 by welding means such as spot welding.

In addition, the structure of the bimetal instrument is, for example,
As disclosed in Japanese Patent No. 4, it is applicable to various types such as a structure in which a lever portion having a pointer and a slit is integrally formed, and this lever is fixed to a pointer shaft. It may be a base.

[Effect of device]

According to the present invention, a pointer shaft is supported on a holder, and a substantially U-shaped bimetal consisting of a movable leg part for winding a heating wire and a temperature compensating part is attached and fixed to the holder, and a slit is formed on the pointer shaft. A lever having is fixed, a pin that engages with the slit is fixed to the free end side of the movable leg, and the bimetal is bent with a heat amount according to the amount of current flowing through the heating wire, and the lever is inserted through the lever. In the bimetal type instrument for connecting and operating the pointer shaft according to the displacement of the bimetal, and rotating and displaying the pointer provided on the pointer shaft, the pin is fixed to the pin by extending in the crossing direction with respect to the pointer shaft. By providing a fixed part and welding and fixing this fixed part to the movable leg part, it is possible to miniaturize the instrument and to prevent the influence on the indicator characteristic of the instrument due to the miniaturization and to keep the instruction in a stable state. You can It is possible to provide a metal-type instrument.

[Brief description of drawings]

1 to 3 show an embodiment of the present invention, wherein FIG. 1 is a sectional view, FIG. 2 is a partially cutaway perspective view, FIG. 3 is a sectional view of an essential part, FIG. 4 and FIG. FIG. 6 is a sectional view of the main part showing another embodiment, and FIG. 6 is a sectional view of the main part showing a conventional example. 11 …… Case (holder), 13 …… Indicator shaft 16 …… Indicator, 17 …… Lever 18 …… Slit, 19 …… Bimetal 20 …… Temperature compensator, 21 …… Movable leg 23 …… Hot wire, 24 ...... Pin 24A, 24B ...... Fixed part

Claims (1)

[Scope of utility model registration request] 1. A substantially U-shaped bimetal, which supports a pointer shaft on a holder and has a movable leg for winding a heat wire and a temperature compensator, is fixed to the holder, and a slit is formed on the pointer shaft. The lever having the above is fixed, a pin engaging with the slit is fixed to the free end side of the movable leg, and the bimetal is bent by the amount of heat according to the amount of current flowing through the heating wire to move the lever. In the bimetal type instrument for connecting and operating the pointer shaft in accordance with the displacement of the bimetal via the pointer, and rotating and displaying the pointer provided on the pointer shaft, the pin is formed to extend in the direction crossing the pointer shaft. A bimetal type instrument characterized in that a fixed part is provided and the fixed part is welded and fixed to the movable leg part.