JPH0721409Y2 - Angle detection mechanism with malfunction prevention function for automobile headlight irradiation angle adjustment device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an angle detection device used in a drive mechanism for vertically adjusting the optical axis direction of a vehicle headlamp.

[Conventional technology]

In general, a vehicle headlamp is installed on a vehicle body with its optical axis leveled.

Therefore, the vehicle headlamp is provided with a manual adjustment mechanism (aiming mechanism) for vertically adjusting the optical axis direction, and the optical axis direction is properly adjusted in an automobile manufacturing factory or an automobile maintenance factory. .

However, even if the optical axis is horizontal in the standard state,
When the state of the load changes, the suspension spring bends and the vehicle body tilts, causing the adjustment state to change. Therefore, in addition to the manual aiming mechanism, an electric remote control type optical axis adjusting mechanism (leveling mechanism) is provided in the vehicle headlamp.

The optical axis adjusting device for a vehicle headlamp is provided with a manual (mostly lead screw type) aiming mechanism and an electric (remote control type) leveling mechanism for the reasons described above.

FIG. 4 is a two-view drawing for explaining the vertical adjustment of the optical axis.

FIG. 4 (A) shows a front view, and 1 is a lamp housing and 2 is a front lens. A reflector (not shown) is fixedly installed in the lamp housing 1, and an arrow Z indicates its optical axis.

Above the lamp housing 1, there are two ball joints on the left and right.
The lamp housing is rotatably supported by 3a and 3b.

A bracket 4 is fixed below the lamp housing 1 and reciprocated in a direction perpendicular to the plane of the drawing by a driving means (not shown). This is shown in a side view as shown in FIG. 4 (B), and the bracket 4 is driven as indicated by an arc-shaped reciprocating arrow ab. As a result, the lamp housing 1 is tilted between the posture shown by the solid line and the posture shown by the broken line in this figure (B), and the optical axis Z swings up and down.

FIG. 5 is an explanatory view of a drive mechanism of a conventional example, and FIG. 5A is a drawing similar to FIG. 4, but the drive mechanism is omitted.

This FIG. 5 (B) is a side view and 5 is a drive unit. (C)
Is a bottom view, and the drive unit 5 is shown.

As shown in (B) above, the drive unit 5 has a male screw member 5a, and a receiving gear 5b having a female screw hole is screwed into the male screw member 5a.

The receiving gear 5b is rotated by a motor provided in the case 5e via a reduction gear (both not shown).

The male screw member 5a is provided with a mechanism (not shown) for locking rotation around the axis, and is screw-fed in the front-rear direction (left-right direction in the drawing) as the receiving gear 5b rotates. It

A nut member 6 is attached to the tip of the male screw member 5a.

The aiming screw 7 attached to the bracket 4 is screwed onto the nut 6.

Accordingly, when the nut member 6 is (relatively) screw-fed by manually turning the aiming screw 7, the lamp housing 1
Is rotated around the ball joints 3a, 3b.

In addition, the receiving gear 5b is driven by the motor (not shown) of the drive unit 5.
When is rotated, the male screw member 5a is moved forward and backward (left and right in the figure), and the lamp housing 1 is moved to the ball joints 3a, 3
The optical axis Z is tilted up and down by being rotated around b.

In this conventional example, the aiming by the aiming screw and the leveling by the drive unit 5 are performed as described above.

The leveling (up and down tilt adjustment) of the headlight by the drive unit
For example, the control method shown in FIG. 6 is used.

The headlamp 7 shown in FIG. 6 is tilted up and down by the forward and reverse rotation of the motor 8.

This vertical tilting is performed by the window comparator 11 of the motor 8 via the relays 9a and 9b.

On the other hand, 10 is a manually operated switch, which is a voltage dividing resistor R ₁ , R
_The rotary switch is used to switch the connection to the voltage dividing terminals connected to ₂ and R ₃ .

The voltage dividing resistors R ₁ , R ₂ , and R ₃ are connected in series, and the voltage V _Z is applied via the fixed resistor R ₄ .

The above voltage V _Z is obtained by converting the input voltage V _C from the power supply into a constant voltage with the zener diode V _D.

The above voltage V _Z is grounded via the potentiometer 10.

The potentiometer 10 rotates as the headlamp 7 tilts up and down, and the voltage V _P corresponding to the tilt angle is taken out.

The combined voltage of the take-out voltage V _S that changes according to the switching operation of the switch 10 and the take-out voltage V _P that changes according to the tilt angle of the headlight 7 is input to the window comparator 11.

If there is an imbalance between the above voltages V _S and V _P ,
The motor 8 is normally or reversely rotated in a direction to eliminate this. Then, the motor 8 is stopped when both the voltages V _S and V _P are balanced.

In this way, when the driver switches the switch 10,
The headlight 7 is tilted at an angle according to the instruction.

In this case, the switching positions 0 ', 1', to 3'of the switch 10 shown in FIG.
The position is set in advance to 1'position for half-loading, 2'position for full load, and 3'position for rear load (state in which the center of gravity of the load is tilted backward).

[Problems to be solved by the device]

In the conventional technique described above, a. The potentiometer performs the action of converting the vertical tilt angle of the headlamp 7 into a voltage signal (V _P ). Since the output voltage signal becomes unstable, it is difficult to detect the angular position with high accuracy, and thus it is impossible to adjust the vertical tilt angle (leveling) with high accuracy.

b. The potentiometer 10 is used to convert the vertical tilting angle of the headlamp 7 into a voltage signal (V _P ), and the operation command signal voltage (V _S ) is changed to the manual changeover switch 10 and fixed resistors R _{1 to} R. _Done by ₃ . Therefore, the angle adjustment pattern is single.

For this reason, in the case of multi-model production of automobiles, in order to perform leveling suitable for each model, it is necessary to design and manufacture a dedicated electrical component for each model.

As a result, the cost reduction effect of mass production cannot be obtained, and the man-hours required for production and assembly are increased.

Not only that, the stock number of spare parts increases, and the stock quantity increases, which is uneconomical.

c. The control circuit including the window comparator 11 operates in response to the potential extracted from the switch 10. Therefore, when the switching contact of the switch 10 has a poor contact, it is in an uncontrolled state, and the motor 8 continues to rotate and does not stop, for example.

When the motor 8 is energized even after the tilting of the headlight 7 reaches the stroke end and contacts the stopper (not shown),
Serious damage such as burnout of the motor occurs.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an angle detection mechanism for leveling, which enables highly accurate leveling and can be adapted to each vehicle type by simple parts replacement. To do.

[Means for Solving the Problems]

As a configuration for achieving the above object, the present invention is an angle detection mechanism in which the divided voltage output voltage changes according to the vertical tilting angle of the headlight, and is used in combination with switch means having a plurality of divided voltage output terminals. In the angle detection mechanism for inputting a combined voltage of the extraction voltage of the angle detection mechanism and the extraction voltage from the switch means to the window comparator, the leveling electric motor of the headlamp can be rotated forward and backward through the relay means, A disk made of an electrically insulating material that rotates as the headlight tilts up and down is configured, and two large and small circles and a plurality of radial straight lines passing through the center of rotation are assumed on the disk. The conductive pattern along the arc of the great circle between the two adjacent straight lines and the conductive pattern along the arc of the small circle between the two adjacent straight lines are alternated. And place them in series Each of the connection points of a large number of fixed resistors connected to each other and each of the conductive patterns are connected to each other, and are arranged in the linear direction, and the conductive patterns along the great circle arc and the small circle arc. A contact electrode facing the conductive pattern along the line is provided, and when the headlamp tilts and the disc rotates, the contact electrode always has the conductive pattern along the small arc and the large arc. Contact conduction to at least one of the conductive patterns along, and when the contact electrode and any of the radial straight lines face each other, the conductive pattern along the small arc and the conductive pattern along the large arc A PNP transistor having a structure in which both contacts and conduct, and whose emitter and collector are connected in the coil circuit of the relay means, a base of the PNP transistor and an electric current of the switch means. It is connected to the emitter and collector between take-out portion, to a connected NPN transistor the base to the power supply side, characterized in that it comprises a.

[Action]

According to the above configuration, the motor is stopped when the contact electrode is brought into contact with and electrically connected to the two conductive patterns.

The motor stops in this way when the contact electrode faces any one of a plurality of radial straight lines, and therefore, the motor can stop at a fixed position with high accuracy regardless of the temperature characteristics and voltage fluctuations of the resistor. You can stop.

Further, it is possible to deal with each vehicle type by exchanging the disc without changing the switch means or the resistors.

When the switching contact of the switch has poor contact, the divided voltage extracted by the switch rises abnormally (becomes a voltage almost equal to the power supply voltage), so the PNP transistor turns off and the PNP transistor turns off, causing the relay to turn off. Cut off the coil circuit of. Therefore, there is no possibility that the motor will stop and continue to rotate without control.

The above-mentioned disc means a member that is mechanically equivalent to a disc, and even if a polygonal plate is used, it is within the technical scope of the present invention.

〔Example〕

FIG. 1 shows an embodiment of an angle detection mechanism with a malfunction prevention function according to the present invention.

This example is an improvement made by applying the present invention to the conventional example (FIG. 6).

The difference from the conventional example (FIG. 6) is that the potentiometer 10 is replaced by series resistors R _{V1 to} R _{V6 for} voltage division,
Further, the rotary plate 12 having a conductive pattern, the contact electrode 13 that comes into contact with the conductive pattern and conducts, and the transistors 21 and 22 are provided.

An explanatory view of the vicinity of the rotary plate 12 is shown in FIG.

Straight six radial through the center of the rotating plate (i.e. radius) r _1, r ₂ ~r ₆ with assuming the assumed and two concentric large arc S _l and small circular arc S _S.

A wide arc-shaped conduction pattern 12a is formed along a portion where the large arc S _l is sandwiched by _two radii r ₁ and r ₂ .

A small arc S _S forms a wide arc-shaped conduction pattern 12b along a portion sandwiched by _two radii r ₂ and r ₃ .

A wide arc-shaped conduction pattern 12c is formed along a portion where the large arc S _l is sandwiched by two radii r ₃ and r ₄ .

A small arc S _S forms an arc-shaped conductive pattern 12d having a width along a portion sandwiched by two radii r ₄ and r ₅ .

A large arc-shaped conduction pattern 12e is formed along a portion where the large arc S ₁ is sandwiched by two radii r ₅ and r ₆ .

The rotating plate 12 is reciprocally rotated in conjunction with the vertical tilting of the headlight 7 (see FIG. 1).

Six fixed resistors R _V1 , R _{V2 to} R _V6 are connected in series, and voltage V
_Z is applied.

Connection point of fixed resistors R _V1 and R _V2 and the conductive pattern
Connect with 12a.

Connection point of fixed resistance R _V2 and R _V3 and the conductive pattern
Connect with 12b.

Connection point between fixed resistance R _V3 and R _V4 and the conductive pattern
Connect with 12c.

Connection point of fixed resistance R _V4 and R _V5 and the conductive pattern
Connect with 12d.

Connection point between fixed resistance R _V5 and R _V6 and the conductive pattern
Connect with 12e.

The contact electrode straddles the large arc S _l and the small arc S _S.
Arrange 13.

The contact electrode 13 includes an inner contact 13s corresponding to the conductive patterns 12b, 12d arranged on the small arc S _S and an outer contact corresponding to the conductive patterns 12a, 12c, 12e arranged on the large arc S _l. The contact 13l is arranged in the radial direction, and the inner and outer contacts 13s and 13l are connected to each other.

Now, when the rotary plate 12 rotates as indicated by the arrow C with the tilt of the headlight, the relative position of the contact electrode 13 with respect to the rotary plate 12 moves as indicated by the arc arrow d and the conductive pattern.
12a, and then the conductive patterns 12b to 12c are sequentially contacted.

When facing the radius r ₂ on the way, the conductive pattern 12a and the conductive pattern 12b are connected, and the fixed resistor R _V2 is short-circuited.

When facing the radius r ₃ on the way, the conductive pattern 12b and the conductive pattern 12c are connected, and the fixed resistor R _V3 is short-circuited.

When facing the radius r ₄ on the way, the conductive pattern 12c and the conductive pattern 12d are connected, and the fixed resistor R _V4 is short-circuited.

When facing the radius r ₅ on the way, the conductive pattern 12d and the conductive pattern 12e are connected, and the fixed resistor R _V5 is short-circuited.

In this way, the contact electrodes 13 are radius _{r 2, r 3, r 4} , or when facing the one of r _5, the motor 8 is stopped in the manner described below, the headlamp 7 is predetermined Stop at the tilt angle. Since the tilting of the headlight stops at the mechanically set contact position, the tilting angle is controlled with high accuracy without being affected by the temperature-dependent change in the resistance value and the change in the power supply voltage.

In FIG. 1, the power supply voltage of the vehicle battery is applied to the input V _C.

Above power supply voltage is fixed resistor R _r and comparator A, B
And one end of the exciting coil of relays A'and B'and NC of relay
It is connected to a pin.

The illustrated diode D ₁ and capacitors C ₁ and C ₂ are for reverse connection prevention, surge absorption, and voltage fluctuation absorption, respectively.

The fixed resistance R _r is for limiting the current flowing through the Zener diode Z _D , and the Zener voltage V _Z is kept substantially constant by this Zener diode.

The above stable voltage V _Z is switched via a fixed resistor R _t.
10 and is grounded via fixed resistors R _{V1 to} R _V6 for _voltage division.

The fixed resistances R _a , R _b , and R _c are set so that R _a = R _c and R _b << R _a and R _c .

As a result, the voltage V _Z is _divided into the voltages V _a and V _b . Then, from the condition of R _a = R _c , V _a ≈V _b .

The reason why V _a = V _b is not set is to ensure the switching operation of the comparator and prevent chattering.

Said voltage V _a is connected to the inverting input of comparator A,
The voltage V _b is connected to the non-inverting input of comparator B.

The non-inverting input of the comparator A and the inverting input of the comparator B are connected and extend to the sensor side (the rotating plate 12 side in this example).

This connection method is called a window comparator and is a well-known technique widely used for detecting whether or not it is within a certain voltage range.

In the figure, if the voltage V _K is an intermediate value between V _a and V _b ,
Outputs O ₁ and O ₂ are LO level. When V _c > V _a > V _b , output O ₁ is LO level. Output O ₂ is HI level. When V _c > V _b > V _a , output O ₁ is HI level output O ₂ becomes LO level.

A circuit extending to the switch 10 via the fixed resistor R _t from V _Z point of the fixed resistor R _t, and a circuit that is grounded via the R _u there.

Let R _t <R ₁ + R ₂ + R ₃ and R _u >> R ₁ + R ₂ + R ₃ .

When the switching position of the switch 10 is set to O ', the conduction state shown in FIG. 3 (A) is established and V _S becomes 0.

Since a current flows through the fixed resistance R _t to cause a voltage drop, the NPN transistor 22 turns ON and the PNP transistor 21 also turns ON.

When the switching position of switch 10 is set to 1 ', R _u >> R ₁
Approximately becomes conductive as shown in FIG. 3 (B) since it is, the value of V _S becomes V _S1.

When the switching position of the switch 10 is set to 2 ', it becomes as shown in FIG. 3 (C), and when the switching position is set to 3', it becomes as shown in FIG. 3 (D).

Therefore, V _S0 = 0 (unit is Volt) V _S1 = V _Z × R ₁ / (R _t + R ₁ ) V _S2 = V _Z × (R ₁ + R ₂ ) / (R _t + R ₁ + R ₂ ) V _S3 = the _{V Z × (R 1 + R} 2 + R 3) / (R t + R 1 + R 2 + R 3).

When the contact electrode 13 is in contact with the middle of the conductive pattern 12a except for both ends thereof, it does not contact with the conductive patterns other than the conductive pattern 12a, and the divided voltage V _S1 is applied via the conductive pattern 12a.

When the contact electrode 13 is in contact with the middle of the conductive pattern 12b except for both ends thereof, it does not contact with the conductive patterns other than the conductive pattern 12b, and the divided voltage V _S2 is applied via the conductive pattern 12b.

When the contact electrode 13 is in contact with the conductive pattern 12c near the middle except both ends, it does not contact the conductive patterns other than the conductive pattern 12c, and is supplied with the divided voltage V _S3 via the conductive pattern 12c.

When the contact electrode 13 is in the vicinity of the middle of the conductive pattern 12d except for both ends thereof, it does not contact the conductive patterns other than the conductive pattern 12d, and the divided voltage V _S4 is applied via the conductive pattern 12d.

When the contact electrode 13 is in contact with the middle of the conductive pattern 12e except for both ends thereof, it does not contact with the conductive patterns other than the conductive pattern 12e, and the divided voltage V _S5 is applied via the conductive pattern 12e.

When the contact electrode 13 is located at a position directly facing the radius r ₂ and contacts across the conductive patterns 12a and 12b, a fixed resistance R
_V2 is shorted, the contact electrode 13 is given a synthetic potential V _1. In FIG. 2, this is designated as r ₂ (V ₁ ).

When the contact electrode 13 is located at a position directly facing the radius r ₃ and contacts across the conductive patterns 12b and 12c, a fixed resistance R
_V3 is shorted, the contact electrode 13 is given a synthetic potential V _2. In FIG. 2, this is designated as r ₃ (V ₂ ).

When the contact electrode 13 is located at a position directly facing the radius r ₄ and contacts across the conductive patterns 12c and 12d, a fixed resistance R
_V4 is shorted, the contact electrode 13 is given a synthetic potential V _3. In FIG. 2, this is designated as r ₄ (V ₃ ).

When the contact electrode 13 is located at a position directly facing the radius r ₅ and contacts across the conductive patterns 12d and 12e, a fixed resistance R
_V5 is shorted, the contact electrode 13 is given a synthetic potential V _4. In FIG. 2, this is designated as r ₅ (V ₄ ).

At this time, the relationship between the above respective potentials is V _S1 > V ₁ > V _S2 > V ₂ > V _S3 > V ₃ > V _S4 > V ₄ > V _S5 .

This provides an effect similar to that of a normal variable resistor.

In FIG. 1, almost all of the current passing through the contact electrode 13 passes through the fixed resistors R _q and R _p and flows into the switch 10 side from the point F. The reason is that the input impedance of the comparator is very large and the resistance value of the fixed resistance R _u is also large.

Next, the operation will be described.

It is now assumed that the switch 10 is in the switching position 0 '.
Since V _S is 0 (volt), the potential at point F is also 0.

At this time, a potential of V _E = V ₁ / R _p / (R _p + R _q ) occurs at point _E , and if this V _E is set so that V _a > V _E > V _b , the comparator The output becomes HI for both O ₁ and O ₂ , the relay does not operate, and the motor 8 is stopped.

At this time (switch 10 is in position 0 '), contact electrode 13
Is in contact with a position other than r ₂ (V ₁ ) shown in FIG. ₂ , the motor 8 rotates, and the headlamp 7 and the rotary plate rotate.
The motor 8 stops when 12 rotates and the contact electrode 13 reaches the r ₂ (V ₁ ) position.

However, in order to perform the above-mentioned operation, the rotation direction of the motor 8 must be set so that the contact electrode approaches the radius r ₂ .

Next, the contact electrode 13 when it is in the r ₃ (V ₂₎ position, the case where switch 10 is operated to switch position 1 '.

At this time, the potential of the V _{S is, V S = V Z × R} 1 / (R t + R 1) becomes, since the potential V _S is equal to the potential of the point F, the potential V _E at point _E V E = (V ₂ −V ₁ ) R _p / (R _q + R _p ).

At this time, since V _E is set so that V _a > V _E > V _b , the comparator outputs O ₁ and O ₂ are both HI, and the motor 8 is stopped.

Considering here that the contact electrode 13 is at the r ₂ (V ₁ ) position and the switch changeover position is 1 ′, the potential V _E ′ at the point _E is V _E ′ = (V ₁ − V _S ) R _p / (R _q + R _p ) = {(V ₁ −V _Z ) × R ₁ / (R _t + R ₁ )} × R _p / (R _q + R _p ), the original stop potential V _E And the potential at this point E becomes higher than V _a by about (V ₁ −V _Z ) R _p / (R _q + R _p ), the comparator A becomes LO, and the relay A ′ goes to the normally open side. It moves and the motor 8 is energized to rotate.

As the motor 8 rotates, the headlight tilts up and down and the rotating plate 12
Rotates in the direction of arrow c (FIG. 2).

In the above, the contact electrode 13 is in the r ₂ (V ₁ ) position and the switch 10
Is a case where the switch is operated to the switching position 1 ′, the potential at the point E becomes higher than V _a , the rotating plate 12 rotates in the direction of arrow c, and the contact electrode 13 reaches the r ₃ (V ₂ ) position. Stop when you do.

Similarly, when the contact electrode 13 is operated to the switching position 1'when the contact electrode 13 is at the position r ₄ (V ₃ ), the potential at the point E becomes lower than V _a, contrary to the above, and the rotating plate 12 becomes opposite arrow. It turns in the c direction and stops when the contact electrode 13 reaches the r ₃ (V ₂ ) position.

Although the above is an example of a typical case, in short, when the switch 10 is operated to the switching position 1 ′ when the contact electrode 13 is in a position other than r ₂ (V ₁ ), the contact electrode 13 moves to r
_The motor 8 rotates in a direction approaching the ₂ (V ₁ ) position, and when the contact electrode 13 reaches the r ₂ (V ₁ ) position, the motor 8 stops and the tilting of the headlight stops.

Switch 10 when contact electrode 13 is in a position other than r ₃ (V ₂ )
Is operated to the switching position 1 ', the contact electrode 13
The motor 8 rotates in the direction approaching the r ₃ (V ₂ ) position, and when the contact electrode 13 reaches the r ₃ (V ₂ ) position, the motor 8 stops and the tilting of the headlight stops.

Switch 10 when contact electrode 13 is in a position other than r ₄ (V ₃ )
Is operated to the switching position 1 ', the contact electrode 13
The motor 8 rotates in the direction approaching the r ₄ (V ₃ ) position, and when the contact electrode 13 reaches the r ₄ (V ₃ ) position, the motor 8 stops and the tilting of the headlight stops.

Switch 10 when contact electrode 13 is in a position other than r ₅ (V ₄ ).
Is operated to the switching position 1 ', the contact electrode 13
The motor 8 rotates in a direction approaching the r ₅ (V ₄ ) position, and when the contact electrode 13 reaches the r ₅ (V ₄ ) position, the motor 8 stops and the tilting of the headlight stops.

As is apparent from the above-described operation, the stop operation of the motor 8 (the tilting stop of the headlight) in this embodiment is caused by the relative movement of the contact electrode 13 and the conduction patterns 12a to 12e accompanying the rotation of the rotating plate 12. Since it is controlled, it can be performed with high accuracy without being affected by resistance value changes due to temperature changes and power supply voltage changes.

Moreover, if a rotating plate having a conduction pattern suitable for each vehicle type is prepared in advance, it is possible to deal with each vehicle type only by exchanging the rotating plate without exchanging electric parts. In addition to cost reduction, it is easy to manage production processes and spare parts.

The above description of the operation is for the case where the switching contact of the switch 10 is in contact with any one of the positions 0 ′ to 3 ′, but if this contact becomes defective, R _t << R _u Therefore, V _S ≈V _Z , and the NPN transistor 22 turns off.

Therefore, the PNP transistor 21 is turned off, and the coils of the relays 9a and 9b are not energized regardless of the operation of the window comparator 11. Therefore, there is no possibility that the motor 8 will stop and rotate in an uncontrolled state.

[Effect of device]

As described above, when the present invention is applied, highly accurate leveling is possible, and it is effective for cost reduction, and moreover, it can be adapted to each vehicle type by simple parts replacement.

In addition, even if contact failure occurs in the switching contact of the manual operation switch, there is no possibility that the vertical tilt drive motor of the headlamp will rotate in an uncontrolled state.

[Brief description of drawings]

1 to 3 show an embodiment of an angle detection mechanism with a malfunction prevention function according to the present invention, FIG. 1 is a wiring diagram, and FIG. 2 is an explanatory diagram depicting the vicinity of a rotating plate,
3 (A) to (D) are operation explanatory views. FIG. 4 is an explanatory view of the optical axis adjustment, FIG. 5 is an explanatory view of a conventional drive mechanism, and FIG. 6 is a control circuit diagram thereof. 7 ... Headlight, 8 ... Motor, 9a, 9b ... Relay, 10 ... Potentiometer, 11 ... Wind comparator, 12 ... Rotating plate,
12a to 12e ... Conductive pattern, 13 ... Contact electrode, 21 ... PNP transistor, 22 ... NPN transistor.

Continuation of the front page (56) Reference JP 59-143731 (JP, A) JP 59-195442 (JP, A) JP 60-226335 (JP, A) JP 1-153354 (JP , A) Actual opening Sho 58-132746 (JP, U) Actual opening flat 2-78435 (JP, U) Actual opening Sho 59-14729 (JP, U) Actual opening flat 2-7137 (JP, U) Actual opening flat 2-6644 (JP, U) Actually opened 63-22249 (JP, U) Actually opened 62-90841 (JP, U) Actually opened 63-156842 (JP, U) Actually opened 2-13838 (JP, U)

Claims (1)

[Scope of utility model registration request] 1. An angle detection mechanism in which a divided voltage extraction voltage changes according to a vertical tilting angle of a headlight, which is used in combination with a switch means having a plurality of divided voltage extraction terminals, and is an extraction voltage of the angle detection mechanism. In the angle detection mechanism for inputting the combined voltage of the output voltage from the switch means and the wind comparator to the forward / reverse rotation of the motor for leveling the headlamp through the relay means, the headlamp can be tilted up and down. A disk made of an electrically insulating material that rotates together is formed, and two large and small circles and a plurality of radial straight lines passing through the center of rotation are assumed on the disk, and two adjacent straight lines are used. The conductive pattern along the arc of the great circle in the sandwiched part and the conductive pattern along the arc of the small circle in the part sandwiched by two adjacent straight lines are alternately arranged and connected in series. Of multiple fixed resistor connection points Each of them is connected to each of the conductive patterns, and the contact electrodes are arranged in the straight line direction and are opposed to the conductive pattern along the great circular arc and the conductive pattern along the small circular arc. When the headlamp tilts and the disc rotates, the contact electrode is always in contact with at least one of the conductive pattern along the small arc and the conductive pattern along the large arc. And, when the contact electrode and any one of the radial straight lines face each other, the contact electrode is in contact with both the conductive pattern along the small arc and the conductive pattern along the large arc, and A PNP type transistor having an emitter and a collector connected in the coil circuit of the relay means, and an emitter and a collector connected between the base of the PNP type transistor and the voltage extracting portion of the switch means. And an NPN transistor whose base is connected to the power supply side, and an angle detection mechanism with a malfunction prevention function for an automobile headlamp irradiation angle adjustment device.