JP2000052811A - Assembly structure of vehicular measuring instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To fit and connect an instrument movement to a circuit board, and a dial to the instrument movement in a single operation by fixing an analog instrument body only to the circuit board. SOLUTION: Locking pawl pieces 26 and locating pins 27 provided at each instrument movement 12 are engaged into locking holes 28 and positioning holes 29 provided in a circuit board 16. Locking between a movement case 25 and the circuit board 16, particularly the thickness direction of the circuit board 16, is maintained by locking action of the locking pawl pieces 26 and locking holes 28, and the dislocation of the movement case 25 in the plate face direction of the circuit board 16 is regulated by close fitting between the locating pins 27 and the positioning holes 29. Connection between the movement case 25 and the circuit board 16 can therefore be ensured in a single operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an assembling structure of an analog instrument installed, for example, in front of a driver's seat of an automobile.
Further, the present invention relates to a mounting structure of a vehicle instrument which can prevent thermal deformation of a dial and improve luminance characteristics.

[0002]

2. Description of the Related Art A conventional instrument assembly structure for mounting a plurality of analog instruments constituting a vehicle instrument in a housing is shown in FIG. 5, for example. The configuration will be described with reference to FIG.

[0003] Reference numeral 1 denotes an analog instrument main body constituting a vehicle instrument, and the instrument main body 1 includes a movement 1A.
A pointer 1C attached to the tip of a pointer shaft 1B expended from the movement 1A, and a dial 1D for displaying a value indicated by the pointer 1C.
The circuit board 2 is fixed to the back of the movement 1A by a plurality of mounting screws 3. In FIG. 5, the number of the instrument bodies 1 fixed to the circuit board 2 is one, but a plurality of the instrument bodies 1 are usually fixed using the attachment screws 3.

On the front surface of the movement 1A, a light guide plate 4 for transmitting and illuminating the dial 1D is provided.
Are fixed to the movement 1A by mounting screws 3, and the peripheral edge of the dial 1D is engaged and held by the upper housing 4. Reference numeral 5 denotes a protective cover that covers the back surface of the circuit board 2, reference numeral 6 denotes a front cover attached to the front of the upper housing 4, and reference numeral 7 denotes an illumination sphere connected to and held by the circuit board 2.

[0005]

In a conventional vehicle instrument having such an assembly configuration, the connecting structure between the movement 1A of the instrument main body 1 and the circuit board 2 has a plurality of attachments. Since the dial 1D to be mounted on the front side of the movement 1A is a screwed structure using the mounting screw 3, the circuit board 2 and the dial 1D are mounted on the movement 1A. In addition to the increased number of mounting screws 3 used, the number of parts increases, and the screwing operation for screwing the large number of mounting screws requires a great deal of trouble.

The dial 1D is designed with a plurality of instruments (for example, a speedometer,
The scales, characters, etc. of a tachometer, a fuel gauge, a water temperature gauge, etc.) are formed in one continuous large dial, and the dial is attached to the circuit board 2 on which a plurality of instrument bodies are assembled. , Dial 1
When the D, the movement 1A, and the circuit board 2 are assembled in a three-piece manner with mounting screws, the dial 1D is formed of a material having a relatively large linear expansion coefficient (such as polycarbonate), whereas the circuit board 2 is Since it is formed of a material having a relatively small coefficient of linear expansion (eg, glass-epoxy, phenol, etc.), a dial plate having relatively low rigidity will be elongated and deformed in a high-temperature situation, for example, in summer. Alternatively, a problem may be considered that the pointer shaft hole of the dial plate interferes with the pointer shaft hole through which the pointer shaft penetrates, and a force is applied to the movement 1A due to thermal deformation of the dial plate. The connection pins (terminals) that electrically connect the board 2 act on the soldered portions on the circuit board 2 side,
There is a concern that stress may be applied to the soldered portion, and eventually contact failure may occur.

In the conventional instrument main body mounting mode, a dial 1D is superimposed on the front surface of the movement 1A via a light guide plate 4, and the dial 1D and the light guide plate 4 are provided in a mounting hole 8 formed therein. The mounting screw 3 is inserted and screwed from the front side of the dial 1D into the mounting hole 8 formed in the light guide plate 4 and the mounting screw 3 inserted into the mounting hole 8. The light that has propagated through the light guide plate is blocked, and the light does not propagate to the rear side from the mounting screw, so that the light is darkened and light unevenness occurs, and the light guide performance is reduced. There was a problem that the aesthetic appearance of the vehicle instrument was impaired due to the projecting mounting screw head located on the surface.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems. In order to attach an instrument movement to a circuit board and to attach a dial to the instrument movement, instead of using mounting screws, a locking pin is used. It is a first object of the present invention to perform one-touch connection using a locking force of a locking claw or the like.

Further, the present invention provides a vehicle instrument mounting structure capable of effectively absorbing the thermal deformation of the dial by making the mounting structure of the dial which is easily thermally deformed a sandwiched structure between the light guide plate and the upper housing. This is the purpose of 2.

According to the present invention, even if the scale of the dial and the pointer are misaligned due to the thermal deformation of the dial,
A third object is to provide a vehicle instrument mounting structure capable of reducing the finger error.

[0011]

In order to achieve the first and second objects, according to the first aspect of the present invention, a circuit board and an analog instrument are provided in an internal space defined by a lower housing and an upper housing. A vehicle instrument including a main body therein is characterized in that the analog instrument main body is fixed to a circuit board only, and the vehicle instrument is assembled.

According to a second aspect of the present invention, in addition to the first aspect, the assembly structure of the analog instrument main body and the circuit board is integrated with the analog instrument main body outside the movement case of the analog instrument main body. And a plurality of locking claws resiliently displaced in a direction crossing the axis of the movement case and a plurality of locking claws which are expendable in a direction parallel to the axis of the movement case, and penetrating the circuit board from front to back. And an assembling structure of a vehicle instrument comprising a positioning hole for inserting the locating pin and a plurality of locking holes for fitting and locking the locking claw pieces. I have.

In claim 3, claim 1 or claim 2
In addition, a light guide plate and a dial located in front of the light guide plate are superimposed on the front of the lower housing, and the dial is sandwiched between the lower housing and the upper housing corresponding to the lower housing. It is characterized in that it is an assembly structure of a vehicle instrument.

According to a fourth aspect of the present invention, in order to achieve the third object, the dial has a horizontally long shape.
It is characterized in that it is a structure for assembling an instrument for a vehicle in which a speedometer is arranged at the center of the dial.

According to a fifth aspect of the present invention, in addition to the fourth aspect, a fuel gauge is arranged at a side end of the dial, and the pointer pointing to an empty scale position on the dial is parallel to the longitudinal direction of the dial. It is characterized by a structure for assembling a vehicle instrument.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail based on an embodiment shown in the drawings.

Reference numeral 11 denotes a main body of an analog type instrument.
And the pointer axis 1 expended from this instrument movement 12
3 is attached to the tip of the pointer 3. 1
Reference numeral 5 denotes a lower housing having an open back surface, and a circuit board 16 is provided in the lower opening of the lower housing 15 so as to close the opening. A plurality of movements 12 are mounted, and the mounting structure will be described later.

Reference numeral 17 denotes a light guide plate superimposed on the surface of the lower housing 15, and the light guide plate 17 is
The light is illuminated from the illumination lamp 18 which is held by the circuit board 16 and is electrically connected, and is surface-emitted. Reference numeral 19 denotes a dial which is superimposed on the light emitting surface of the light guide plate 17, and the dial has a scale and characters of a plurality of instruments (for example, a speedometer, a tachometer, a fuel gauge, a water temperature gauge).
As shown in FIG. 4, the mounting structure of the dial 19 is formed by a lower housing 15 and an upper housing 20 corresponding to the front surface of the lower housing 15. And is sandwiched by. Further, a through hole 21 for positioning is formed in an appropriate portion of the peripheral portion of the dial 19, and in the through hole 21,
The locking projections 22 protruding from the peripheral edge of the lower housing 15 are fitted to prevent displacement of the dial 19 in the plate surface direction. 23 is the upper housing 2
Reference numeral 0 denotes a transparent or translucent front cover attached to the front of the circuit board 16, and reference numeral 24 denotes a rear cover attached to the back side of the circuit board 16.

Next, the structure for attaching the instrument movement 12 to the circuit board 16 will be described with reference to FIGS. On both sides of the movement case 25 accommodating the instrument movement 12, the respective locking claw pieces 26 which are expendable in the axial direction of the movement 12 and can bend in the direction intersecting with the axial center, and the rear direction of the movement case 25 (indicators) Locate pin 2 projecting in the direction parallel to the axis of
7 is formed integrally with the instrument movement 12.

The circuit board 16 has respective locking holes 28 into which the respective locking claws 26 are fitted and locked.
And the positioning hole 2 into which the locate pin 27 is closely fitted.
9 are drilled for the number of instrument movements to which they are attached.

Note that reference numeral 30 shown in FIG.
Is a terminal supported and fixed integrally with the instrument movement 12, and this terminal 30 is connected to the instrument movement 12
Are connected at each end of the cross-wound coil.

The procedure for assembling the instrument for a vehicle using each of the above-described components will now be described. First, each instrument movement 12 is provided in a locking hole 28 and a positioning hole 29 provided in the circuit board 16. Locking claw piece 2
6 and the locating pin 27 are engaged with each other,
The movement of the movement case 25 and the circuit board 16, particularly in the thickness direction of the circuit board 16, is maintained by the locking action of the locking pin 28 and the locking hole 28, and the movement is achieved by the close fitting of the locating pin 27 and the positioning hole 29. The displacement of the case 25 in the plate surface direction of the circuit board 16 is regulated, and the connection between the movement case 25 and the circuit board 16 can be secured by one-touch operation. Next, the terminals 30 provided on the instrument movement 12 are soldered to the circuit pattern of the circuit board 16 to complete the mounting of the instrument movement 12 on the circuit board 16.

Next, after the lower housing 15 is put on the front side of the circuit board 16 and the instrument movement 12, the light guide plate 17 and the dial 19 are overlaid on the front surface of the lower housing. When the dial 19 is superimposed on the light guide plate 17, a locking projection 22 provided on the lower housing 15 is provided in a through hole 21 formed in a peripheral portion of the dial 19 as shown in FIG. The positioning of the dial 19 in the plate surface direction with respect to the lower housing 15 is ensured by engaging with.

Next, an upper housing 20 which is sandwiched in cooperation with the lower housing 15 is put on the dial 19,
The upper housing 20 and the lower housing 15 are fixed using mounting screws, engaging claws and the like (not shown). afterwards,
The pointer 14 located on the surface of the dial 19 is attached to the pointer shaft 13 of the instrument movement 12, the front cover 23 is attached on the upper housing 20, and the rear cover 24 is attached on the back side of the circuit board 16. This constitutes a vehicle instrument.

As described above, in the above embodiment, for example, the analog type instrument main body 11 such as a speedometer, a fuel gauge and a water temperature gauge is fixed only to the circuit board 16, and the dial 19 and the analog type instrument main body 11 are connected to each other. Avoiding joins. For this reason, the difference between the coefficient of thermal expansion of the circuit board 16 and the coefficient of thermal expansion of the dial 19 causes the analog instrument body 11 fixed to the circuit board 16 and the dial 19 to undergo thermal expansion deformation. As a result, the analog type instrument main body 11
It is conceivable that a finger error due to the pointer of the analog type instrument slightly occurs due to a positional shift between the character and the dial.

Therefore, in this embodiment, as shown in FIG. 5, the speedometer 3 which is indispensable as information during operation is provided.
1 is disposed at the central portion where the thermal deformation of the dial 19 due to thermal expansion is the smallest, and further, a fuel gauge 32 is disposed on the left side of the speedometer 31 and a thermometer 33 is disposed on the right side of the speedometer 31. I have. The axial positions of the pointer shafts 32A and 33A of the fuel gauge 32 and the thermometer 33 are aligned with the horizontal line 34 passing through the axis of the speedometer pointer shaft 3A located at the center of the dial 19.
It is positioned so as to be located on the upper side.

Further, in the fuel gauge 32, the position of the scale plate of the fuel gauge 32 is set so that the empty display scale E is displayed on the horizontal line 34.
The pointer pointing to the empty position 2 is positioned so as to be horizontal.

By arranging the speedometer 31 at the center of the dial 19 in this way, even if the dial 19 expands and contracts due to the thermal expansion effect, the amount of expansion and contraction at the center of the dial 19 is relatively small. Therefore, the pointing error between the pointer and the scale can be reduced.

In the left and right horizontally long dial 19, the heat expansion and contraction in the horizontal direction at the left and right side edges of the dial 19 where the fuel gauge 32 and the thermometer 33 are located are determined by the central portion of the dial. However, since the angle change due to the thermal expansion in the horizontal direction is small, if the pointer of the fuel gauge 32 is pointed to the horizontal position, that is, the empty position in a position parallel to the longitudinal direction of the dial, the vicinity of the empty is possible. Can be reduced. Therefore, it is possible to improve the instruction accuracy when the amount of fuel is small.

In the above-described embodiment, an example is shown in which the position of the fuel gauge 32 is set on the horizontal axis passing through the pointer axis 31A of the speedometer 31.
The present invention is not limited to this, and it goes without saying that the pointing accuracy of the pointer near the empty can be improved simply by directing the pointer pointing to the empty scale of the fuel gauge in parallel with the longitudinal direction of the dial.

In the case of the dial 19 which penetrates the pointer shafts 31A, 32A, 33A of the instruments 31, 32, 33 which are fixed by the circuit board, the dial 19
Pointers 31A and 32
In order to prevent the contact between the A, 33A and the edge of the pointer through hole provided in the dial, for example, in FIG. 19
A gap 36 sufficient to absorb the thermal expansion and contraction of the light guide plate is secured, and a guide is also provided between the outer surface of the pointer shaft and the inner peripheral surface of the pointer through hole 37 provided in the light guide plate 17 shown in FIGS. Light plate 17
A sufficient gap is provided to absorb the thermal expansion and contraction.

As described above, in the vehicle instrument according to the present embodiment, the large single dial 19 on which the scales and characters of a plurality of instruments located on the front portion of the instrument movement 12 are formed is provided. The through-hole 21 provided on the peripheral portion is locked with the locking projection 22 provided on the lower housing 15,
The dial 19 is positioned with respect to the lower housing 15, and the periphery of the dial 19 is
5 and the upper housing 20, and the dial 19 is maintained in a non-fixed state with the circuit board 16 holding the instrument main body 11. 19, the difference between the thermal expansion of the circuit board 16 and the dial 19, that is, even if the thermal expansion of the dial 19 is larger than the thermal expansion of the circuit board 16, the heat of the dial 19 becomes larger. The expansion force is the circuit board 1
6, the thermal expansion of the dial 19 is effectively absorbed between the instrument movement.

Therefore, even if the dial 19 is apt to undergo thermal expansion, the instrument movement fixed on the dial 19 and the circuit board 16 is not fixed by the mounting screws, so that it is held without thermal deformation. You. The fixing means of the dial 19 is fixed by positioning with the through holes 21 and the locking projections 22 provided in the dial 19 and by clamping between the lower housing 15 and the upper housing 20. Since no mounting screws for fixing the fixing member 19 are used, it is possible to reduce the number of parts and to improve the mounting work due to the reduction of the mounting screws.

The mounting structure of the instrument main body 11 to the circuit board 16 is achieved by using a locking claw 26 and a locking hole 28 without using mounting screws.
Locating pin 29 and positioning hole 2
9, the workability of mounting the instrument body 11 to the circuit board is greatly improved, and the number of mounting parts such as mounting screws is reduced, thereby improving the economic efficiency. I do.

Further, in the present embodiment, a screw hole for screwing the dial 19 is formed in the light guide plate 17 as a dial plate mounting structure, and mounting screws are not inserted into the screw holes. As a result, the light guide is not hindered by the screw holes and the mounting screws as in the prior art, and high brightness performance is obtained.Furthermore, the heads of the mounting screws are protruded from the surface of the dial to improve the appearance. The disadvantage of being damaged can also be effectively avoided.

In this embodiment, the speedometer 31 is
It is arranged at the center of the dial 19 having the smallest amount of thermal expansion and contraction, and the pointing error between the pointer and the dial graduation can be reduced. Also, the direction of the pointer indicating the empty scale position of the fuel gauge 32 is set so as to be parallel to the direction of the largest thermal expansion and contraction of the dial, so that the fuel gauge 3
The finger error in the vicinity of the empty scale in Step 2 can be reduced, and the pointing accuracy can be increased particularly when the fuel level is low.

[0037]

As described above, according to the structure for assembling an instrument for a vehicle according to the present invention, it is possible to reduce the number of mounting parts required for the assembling work. Workability is greatly improved. Further, since both members of the dial and the circuit board having different coefficients of thermal expansion are not integrally connected, it is possible to effectively absorb a difference in thermal expansion force generated between the two members, thereby providing a thermal deformation. It is possible to prevent the deformation of the dial which is apt to occur. Further, since the mounting screw insertion hole is not formed in the light guide plate or the mounting screw is not inserted, the light guide property of the light guide plate is not hindered, and desired light guide characteristics can be obtained.

Further, since the speedometer 31 is arranged at the center of the dial 19 having the smallest amount of thermal expansion and contraction, the pointing error between the pointer of the speedometer 31 and the dial scale is reduced even if the dial is thermally expanded and contracted. be able to. Further, in the case of the fuel gauges 32 and the like disposed at the left and right ends of the dial 19 having a relatively large thermal expansion and contraction amount, the direction of the pointer pointing to the indicating unit in the fuel gauge 32 or the like for which the pointing accuracy is to be improved is changed. Is set so as to be parallel to the large thermal expansion and contraction direction, thereby reducing the finger error of the meters disposed at the left and right ends of the dial.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing an instrument assembly structure according to the present invention.

FIG. 2 is a plan view of a main part showing a combined state of the circuit board and the instrument movement showing the instrument assembly structure according to the present invention.

FIG. 3 is a front view of the instrument movement showing the instrument assembly structure according to the present invention.

FIG. 4 is an enlarged sectional view of a main part showing a structure for assembling an instrument according to the present invention.

FIG. 5 is a front view showing the entire instrument according to the present invention.

FIG. 6 is a cross-sectional view showing a conventional instrument assembly structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 ... Instrument main body 12 ... Instrument movement 13 ... Pointer shaft 14 ... Pointer 15 ... Lower housing 16 ... Circuit board 17 ... Light guide plate 18 ... Illumination lamp 19 ... Dial plate 20 ... Upper housing 21 ... Through hole 22 ... Locking protrusion 23 ... Front cover 24 ... Rear cover 25 ... Movement case 26 ... Locking claw 27 ... Locating pin 28 ... Locking hole 29 ... Positioning hole 30 ... Terminal 31 ... Speedometer 32 ... Fuel meter 33 ... Temperature meter 35 ... Pointer through hole 36 ... Gap 37 ... pointer through hole

Claims (5)

[Claims] A circuit board (16) is provided in an internal space defined by a lower housing (15) and an upper housing (20).
And an analog instrument main body (11) inside, wherein the analog instrument main body (11) is fixed only to the circuit board (16). 2. The fixing structure between the analog type instrument main body (11) and the circuit board (16) comprises an analog type instrument main body (1).
The locating pin (27) formed integrally with the analog instrument main body outside the movement case (25) of 1) and expended in a direction parallel to the axis of the movement case (25), and the movement case (2
5) A plurality of locking claw pieces (26) elastically displaced in a direction crossing the axis of (5) and a circuit board (16) are penetrated to the front and back, and the above-mentioned locating pin (27) is fitted therein. 2. The assembling structure for a vehicle instrument according to claim 1, comprising a positioning hole (29) to be engaged and a plurality of locking holes (28) for fitting and locking said locking claw pieces (26). . 3. A light guide plate (17) and a dial (19) located in front of the light guide plate (17) are superimposed on the front of the lower housing (15).
The assembly structure for a vehicle instrument according to claim 1, wherein the dial (19) is sandwiched between the upper housing (20) corresponding to the lower housing (5) and the lower housing (15). . 4. The assembling structure of a vehicle instrument according to claim 3, wherein the dial has a horizontally long shape, and a vehicle speed indicator is arranged at the center of the dial. . 5. The assembling structure of a vehicle instrument according to claim 4, wherein a fuel gauge is arranged at a side end portion of the dial, and a pointer pointing to an empty graduation position on the dial is oriented in a longitudinal direction of the dial. An assembling structure of an instrument for a vehicle, which is parallel to a direction.