JPH08164796A - Electric tiltable door mirror - Google Patents

Abstract

PURPOSE: To provide an electric tiltable door mirror that is less in vibration at the time of automobile traveling, therefore easy to sight a rear background. CONSTITUTION: A main gear 23 is clamped to the side of a mirror base 20, while a second shaft, separate from a first shaft 25 serving as a turning shaft of a door mirror, is set up at the side of a bracket 24, and a pinion 33 in mesh with the main gear is attached to this second shaft. This pinion is connected to a motor 46 via a concentric clutch plate 34, a spur gear 36 and a reduction gear group. The ratio of numbers of teeth of this pinion to the main gear is set within the range of 1/10 to 1/2. Those of main gear, pinion, clutch plate, spur gear, reduction gear group and worm gear of motor are all composed of plastics.

Description

Detailed Description of the Invention

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric foldable door mirror that is fixed to a front door of an automobile and can be tilted in the front-rear direction of a vehicle body.

[0001]

2. Description of the Related Art Conventionally, as this type of electric retractable door mirror, for example, one having a structure shown in FIGS. 5 and 6 is known. In the figure, 1 is a mirror base fixed to the front door of the vehicle body, 2 is a center shaft having a length of about 40 mm which is formed substantially perpendicular to the mirror base 1, and 3 is rotated on the center shaft 2 on the mirror base 1. It is a bracket that can be supported. Reference numeral 4 is a ball bearing for smoothly rotating the bracket 3 with respect to the mirror base 1. A mirror (not shown) and a mirror driving device (not shown) for driving the mirror are attached to the bracket 3. A pair of flat surfaces 5 is formed on the center shaft 2 at a portion located above the bracket 3. A ring-shaped clutch 6 is axially movably supported on the shaft 2 via a washer 7 on the bracket 3, and has several claws 8 and 8. This clutch
6 is formed with a flat surface 9 which corresponds to the flat surface of the shaft 2, so that the clutch 6 cannot rotate with respect to the shaft 2. Reference numeral 10 denotes a clutch gear rotatably supported by the shaft 2, the lower part of which is hollowed out, and the hollowed out portion 11 accommodates the clutch. At the ceiling portion of the cut-out portion 11, the claw portions 8 and 8 of the clutch 6 are provided.
There are formed recesses 12, 12 that engage with each other. Thirteen
Is a coil spring that penetrates the shaft 2 and elastically presses the clutch gear 14 via the washer 14,
A fixing ring 15 fixes the upper end of the coil spring 13 near the upper end of the center shaft 2.
Reference numeral 16 is a reduction gear group, and 17 is a reversible motor that drives the clutch gear 10 to rotate forward and backward. In the above-mentioned configuration, the normal clutch gear 10 and the clutch 6 are arranged such that the coil springs 13 generate the respective claws 8 and 8 and the recesses 12 and 12.
Mesh with each other, and the two are in a mechanically coupled state. Therefore, when the motor 17 rotates, its driving force is transmitted to the clutch 6, which rotates it, and further the clutch 6
The force that tries to rotate works. However, since the clutch 6 is supported so as not to rotate with respect to the center shaft 2, the bracket 6 itself rotates with respect to the shaft 2. By rotating the motor 17 forward and backward, the bracket 3 is rotated to the normal position or the retracted position.

Due to an obstacle colliding with a door mirror,
When an external force is suddenly applied from the front or the rear, the meshing portion of the clutch gear 10 and the clutch 6 is disengaged against the spring force of the coil spring 13, and the bracket 3 becomes rotatable with respect to the center shaft 2. Turns rapidly toward the rear or front of the vehicle. This is because the magnitude of the rotational force of the clutch gear 10 due to the impact force exceeds the meshing force between the clutch gear 10 and the clutch 6 due to the coil spring 13.

[0003]

Usually, in the door mirror having the above structure, the clutch, the clutch gear, the reduction gear group, etc. are often made of sintered metal having high mechanical strength. There is a problem that the weight on the side increases, the vibration of the mirror increases during traveling, and it becomes difficult for the driver to visually recognize the rear.

Further, since the bracket side component is made of metal, it is necessary to withstand the high torque. Therefore, the center shaft to which the driving force is transmitted and the base plate for fixing the center shaft must also be made of metal. , Is a factor that hinders the weight reduction of the vehicle body.

The present invention has been made in order to solve such a problem, and provides a structure for minimizing the vibration of the mirror.

[0006]

SUMMARY OF THE INVENTION The present invention is directed to a mirror base formed on the front door of an automobile so as to project to the outside of the vehicle body, a bracket rotatably supported on the mirror base, and a bracket on the side of the bracket. In a door mirror having a mirror tilting device arranged and a mirror case accommodating a mirror, a first shaft that allows the bracket to rotate with respect to the mirror base, and a rotation of the bracket formed on an upper surface of the mirror base. A main gear having the same center of motion, a second shaft vertically supported by the bracket at a predetermined distance from the first shaft, and a pinion meshed with the main gear that is supported by the second shaft and rotates. A gear and a gear which is supported by the second shaft and is disposed above the pinion gear and in contact with the pinion gear. -Gear, a clutch plate that is formed on the contact surface of the spur gear and the pinion gear, and transmits or blocks the rotational force of the spur gear to the pinion gear, and is fixed to the bracket, and the rotational driving force is transmitted to the spur gear. A reversible motor, and a reduction gear group interposed between the reversible motor and the spur gear, and the ratio A / B of the number of teeth A of the pinion gear to the number of teeth B of the main gear is 1 / 10 to 1/2
Is set within the range of, and the above pinion gear,
The spur gear and the reduction gear group are made of plastic.

Further, according to the present invention, in the above structure, the mirror base and the main gear can be integrally formed of plastic, and the bracket and the first shaft can be integrally formed of plastic.

[0008]

When the motor rotates, its driving force is reduced by the reduction gear group and transmitted to the spur gear, and further transmitted to the pinion gear via the clutch. The rotating force of the pinion gear is applied to the main gear with which it meshes, but since the main gear is formed integrally with the mirror base, it does not rotate with respect to the mirror base, but conversely the pinion gear side, that is, the bracket rotates. To do. Thus, the forward / reverse rotation of the motor causes the door mirror to retract or stand up.

When an external force is applied to the door mirror from the front or the rear due to a collision with an obstacle or the like, the clutch is disengaged, and the door mirror rotates rearward or frontward about the shaft by the rotation of only the spur gear. At this time,
The rotation torque applied to the spur gear is equal to the tooth ratio 1/10 to 1/2 of the main gear and the spur gear,
The torque applied to the clutch is reduced as well.

[0010]

1 to 3, reference numeral 20 denotes a mirror base fixed to the front door of an automobile so as to project outward from the vehicle body, and has a horizontal plane 21. A circular hole having a diameter of about 14 mm is formed substantially at the center of the horizontal plane 21. 22 is drilled. 23 is
A main gear having a diameter of 42 mm is formed integrally with the mirror base 20 around the circular hole 22 on the horizontal plane 21, and 20 teeth are formed in a half portion of the main gear. When gears are formed on the entire circumference of the main gear 23, the number of gears is 40, but the gears that are not used in this embodiment are not formed. Hereinafter, the number of teeth A of the main gear 23 refers to the number of teeth when gears are formed on the entire circumference even if gears are actually formed only on a part of the circumference. 24 has a hollow cylindrical first shaft 25 having an outer diameter equal to the diameter of the circular hole 22, which is formed by protruding downward from the bottom surface of the bracket. This first
By supporting the shaft 25 through the circular hole 22, the bracket 24 is rotatably supported by the mirror base 20. The reason why the first shaft 25 is projected downward from the bracket 24 is that if it is projected upward, the degree of freedom in arrangement of other components and the space are reduced. The length of the first shaft 25 may be the total thickness of the mirror base 20 and the bracket 24, for example, about 25 mm. The first shaft 25 has a plurality of notches 26 formed in the axial direction around the first shaft 25, and a locking portion 27 having a wedge-shaped cross section at the lower end. Since the wall portion of the first shaft 25 is elastically deformed by the notch 26, the first shaft 25 is pushed into the circular hole 22 and the lower end locking portion 27 is hooked on the lower end portion of the circular hole 22.
4 is pivotally supported by the mirror base 20.

Reference numeral 27 denotes a concave groove formed in an arc shape around the main gear 23, that is, a portion where the gear is formed on the plane portion 21 of the mirror base 20, and 28 denotes the concave groove 27.
It is a bracket 24 side protrusion located inside. This groove 2
The rotation angle of the bracket 24 with respect to the mirror base 20 is regulated by 7 and the protrusion 28. That is, the storage position and the forward tilt position of the door mirror are determined. 29
Is a mirror drive attached to the bracket 24,
Reference numeral 30 is a mirror whose horizontal and vertical angles are adjusted by the mirror driving device 29, and 31 is a mirror case fixed to the bracket 24.

The mirror base 20 main gear 23 bracket and the first shaft are integrally formed of plastic such as fiber reinforced polyethylene terephthalate resin or fiber reinforced nylon resin. That is, although they can be individually configured and then integrally joined by screws, welding, fitting, etc., they are preferably integrally formed to simplify the forming work. For these moldings, for example, an injection molding method can be used.

Reference numeral 32 denotes the bracket 23 at a position separated from the first shaft 25 by about 30 mm in the outer side direction of the vehicle body.
A second shaft vertically supported by the lower end of the second shaft is supported inside the protrusion 28 through the hole 51. Protrusion 2
The surface of No. 8 facing the main gear 23 is opened. A pinion gear 33 having a diameter of 22 mm is fixed to the second shaft 32 and meshes with the main gear 23. The number of teeth of the pinion gear 33 can be 20. Reference numeral 34 denotes a clutch plate integrally fixed to the upper portion of the pinion gear 33, which is formed of a disc body and has four protrusions 35, 35 ... The pinion gear 33 and the clutch plate 34 are rotatably supported by the second shaft 32.

Reference numeral 36 is a spur gear located on the clutch plate 34, and is rotatably supported by the second shaft 32. A circular recess 37 corresponding to the clutch plate 34 is formed on the lower surface of the spur gear 36.
Four grooves 38, 38 having a trapezoidal cross section corresponding to the projections 35 of the clutch plate 34 are provided in the inside 7. 39 is
Coil springs arranged above the spur gear 33, 4
0 is a washer and 41 is a fixed ring. With this fixing ring 41, the washer 40 and the coil spring 3
The upper end of 9 is fixed, and the coil spring 39 is compressed. Due to this compressive force, the spur gear 36 is elastically pressed downward, meshes with the clutch plate 34, and the two are brought into a coupled state. It should be noted that about half the load applied to the spring 13 given as a conventional example is applied to the coil spring 39. Therefore, the coil spring 39 can be reduced in size and weight by about 30% as compared with the conventional one.

Reference numeral 42 denotes a third member supported by the bracket 24.
The shaft supports a worm gear 43 having a different diameter and a double gear 45 including a spur gear 44. The spur gear 43 having a small diameter of the double gear 45 meshes with the spur gear 36. 46 is an electric reversible motor fixed to the bracket 24 side, 47 is a worm gear fixed to the rotating shaft of the motor 46, and this worm gear 46
Meshes with the worm gear 44. The double gear 45 and the worm gear 47 form a reduction gear group 48.
Power for driving the motor 46 and the mirror driving device 29 is supplied from the vehicle body side through a power cord (not shown) wired through the first shaft 25.

The pinion gear 33, the clutch plate 34, the spur gear 36, and the reduction gear group 48 are made of plastic such as nylon resin or polyacetal resin. Also,
The second and third shafts 32 and 42 are made of metal. The upper ends of the second and third shafts 32 and 42 are supported by a case 52 that houses the electric storage structure parts.

Reference numeral 49 is a conductive piece such as a copper plate attached to the upper surface of the main gear 23. Reference numeral 50 is a conductive pattern wired on the rear surface of the opposing bracket 24. The position of the bracket 24 with respect to 20, that is, the use position (standing state) and the storage position are electrically detected.

Next, the operation of the above configuration will be described. When the door mirror in the use position is stored, when the switch inside the vehicle is turned on and the motor 46 is rotated in the forward direction, the driving force is transmitted to the spur gear 36 via the worm gear 47 and the reduction gear group 48. Since the projection 35 of the clutch plate 34 is engaged with the groove 38 on the lower surface of the spur gear 36, the both are in a coupled state, and the driving force is the pinion gear 33.
Conveyed to. The rotational force of the pinion gear 33 tries to rotate the main gear 23 by being applied to the main gear 23. However, since the main gear 23 is fixed to the mirror base 20, it does not rotate, and the main gear 23 does not rotate. As a center, the pinion gear 33, that is, the bracket 24 side rotates around the pinion gear 33. Thus, the door mirror rotates from the used state to the stored state. When it reaches the storage position, the position is electrically detected and the motor 46 is turned off. Further, at this position, the protrusion 28 of the bracket 24 hits one end of the groove 27 of the mirror base 20 and further rotation is prevented. When the door mirror is rotated from the storage position to the use position, the motor 46 is rotated in the opposite direction, and the same operation is performed thereafter.

When an obstacle hits the door mirror in use from the front, the mirror case 3 is attached to the bracket 24.
A large turning force (retracting direction) is suddenly applied via 1.
Due to this turning force, the clutch plate 34 is disengaged from the spur gear 36, the pinion gear 33 becomes free, and it rapidly turns around the main gear 23 to reach the retracted position and stops.
At this time, the spur gear 36, the reduction gear group 48, and the motor 4
Since the above-mentioned turning force is not applied to 6, there is no risk of damage to them. The same operation is performed when an obstacle collides with the door mirror from behind.

Next, the durability of the components to which the collision force is applied will be described. Usually, in consideration of the case where the colliding object is a human body, it is necessary to make the clutch plate 34 disengage from the spur gear 36 when a force of 5 to 7 kgf is applied to the tip of the door mirror so as not to damage the human body. When the force applied to the tip of the door mirror is 6 kgf and the distance from the first shaft 25 to the tip of the door mirror is about 15 cm, the rotational torque applied to the first shaft 25 is about 90 kgf.
・ It becomes cm. Here, since the number of teeth A of the main gear 23 is 40 and the number of teeth B of the pinion gear 33 is 20, the rotational torque applied to the pinion gear 33 is reduced by B / A, that is, 1/2, about 45 kgf · cm. Becomes When the pinion gear 33 is made of plastic, the upper limit is about 45 kgf · cm, and if torque above this is applied, the pinion gear 33 will be
There is a risk that the claw portion 35 of the clutch plate 34, which is integrally formed with, will be destroyed. From this, the pinion gear 33
Is made of plastic, the main gear 23
The ratio B / A of the number of teeth of the pinion gear 33 and that of the pinion gear 33 must be 1/2 or less.

On the other hand, from the viewpoint of aerodynamic resistance and design, there is a limited space for accommodating the electric storage and the standing drive portion, and it is not possible to increase the diameter of the main gear 23 without limit in order to reduce the above gear ratio. It is not possible and the limit is about 60 mm in diameter. In this case, the number of teeth A (module 1) of the main gear 23 can be set to 60 at maximum. On the other hand, when the pinion gear 33 is formed as small as possible, its diameter can be up to about 8 mm, and the number of teeth B can be 6 at this time. From this, the minimum ratio of the numbers of teeth of the main gear 23 and the pinion gear 33 is 1/10. From the above, the tooth number ratio B / A needs to be set within the range of 1/10 to 1/2.

The door mirror mentioned as the conventional example, that is, the door mirror in which the gears and the like constituting the electric storage operation part are made of metal, has a total weight of about 1400 g, of which the mirror base 20 (weight of about 626 g) is excluded. The weight of the door mirror portion is 774 g, and the weight of the driving force transmitting portion such as the clutch is about 98 g. When the first shaft 25, the pinion gear 33, the clutch plate 34, the spur gear 36, the reduction gear group 48, and the worm gear 47 are made of plastic as shown in the above embodiment, the total weight thereof is about 19 g. Also, the bracket 20
By making the side driving force transmitting portion plastic, the main gear 23 on the side of the mirror base 20 that meshes with the side driving force transmitting portion can also be made of plastic. As a result, the weight of the mirror base 20 can be reduced by about 95 g.

Vibrations are transmitted to the door mirrors from the vehicle body while the vehicle is running. As shown in FIG. 4, the center of gravity P of the mirror 30 is normally separated from the fixed point O of the mirror 30 by about 10 mm. Therefore, when the vibration of the door mirror is applied to the mirror 30 via the fixed point O, the left and right sides are indicated by broken lines. Vibrate to. Now, let this angle be a. The angle a increases as the width of vibration (displacement) of the fixed point O increases, and the magnitude of the displacement depends on the weight of the door mirror portion excluding the mirror base 20. As shown in the example, when the weight of the door mirror portion is reduced from 774 g to 695 g, the displacement is
Reduced from 0.07mm to 0.06mm, the angle a is 0.04mm
To 0.02 °. In the actual experiment as well, the decrease in the amplitude angle a made the background reflected on the mirror 30 clear and significantly visible.

[0024]

According to the present invention, the clutch plate is fixed to the second shaft provided on the bracket side different from the first shaft on which the door mirror rotates, and the tooth ratio of the main gear and the pinion gear is Since it is set within the range of 1/10 to 1/2, the rotational torque applied to the clutch plate is set to 1 / the rotational torque applied to the first shaft due to the external impact.
It is possible to reduce it to 10 to 1/2. Therefore,
The driving force transmission component from the motor to the pinion gear,
Since it can be made of plastic, the weight of the door mirror can be reduced. As a result, the vibration of the mirror during traveling can be remarkably reduced, and the background reflected on the mirror can be easily seen, which contributes to safe driving.

Further, according to the present invention, by making the bracket-side drive portion plastic, the mirror base and the main gear, which are conventionally made of metal, can also be made plastic, and therefore the weight can be reduced. Further, since the mirror base and the main gear, and the bracket and the first shaft can be integrally molded by an injection molding method or the like, the number of parts can be reduced and the assembling work can be simplified. You can

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an electric retractable door mirror according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a clutch portion in the embodiment.

FIG. 3 is a schematic diagram for explaining vibration of a mirror.

FIG. 4 is an exploded perspective view for explaining a conventional example.

FIG. 5 is a cross-sectional perspective view for explaining the conventional example.

[Explanation of symbols]

 20 Mirror Base 22 Circular Hole 23 Main Gear 24 Bracket 25 First Shaft 29 Mirror Drive Device 30 Mirror 31 Mirror Case 32 Second Shaft 33 Pinion Gear 34 Clutch Plate 36 Spur Gear 42 Third Shaft 45 Double Gear 46 Motor 48 Reduction Gear Group

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[Procedure amendment]

[Submission date] May 17, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Brief description of the drawing

[Correction method] Change

[Correction content]

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an electric retractable door mirror according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a clutch portion in the embodiment.

FIG. 3 is a schematic diagram for explaining vibration of a mirror.

FIG. 4 is an exploded perspective view for explaining a conventional example.

FIG. 5 is a cross-sectional perspective view for explaining the conventional example.

FIG. 6 is an exploded perspective view for explaining the conventional example.

[Explanation of symbols] 20 ………… Mirror base 22 ………… Circular hole 23 ………… Main gear 24 ………… Bracket 25 ………… 1st shaft 29 ………… Mirror drive unit 30 …… …… Mirror 31 ………… Mirror case 32 ………… 2nd shaft 33 ………… Pinion gear 34 ………… Clutch plate 36 ………… Spur gear 42 ………… 3rd shaft 45 ………… Double gear 46 ………… Motor 48 ………… Reduction gear group

Claims (2)

[Claims] 1. A mirror base formed on the front door of an automobile so as to project to the outside of the vehicle body, a bracket rotatably supported on the mirror base, a mirror tilting device and a mirror arranged on the bracket side. And a main case formed on the mirror base and having the same center as the rotation center of the bracket in a door mirror having a mirror case accommodating A second shaft vertically supported by the bracket at a predetermined distance from the first shaft; a pinion gear supported by the second shaft and rotating with the main gear; and a pinion gear supported by the second shaft. And a spur gear disposed above the pinion gear and in contact with the pinion gear, and the spur gear. Formed on the contact surface of the pinion gear,
A clutch plate for transmitting or blocking the rotational force of the spur gear to or from the pinion gear, a reversible motor fixed to the bracket and transmitting its rotational driving force to the spur gear, and interposed between the reversible motor and the spur gear. And a ratio B / A of the number of teeth A of the main gear and the number of teeth B of the pinion gear are set within a range of 1/10 to 1/2, and An electric retractable door mirror characterized in that the pinion gear, the spur gear, and the reduction gear group are formed of plastic. 2. The electric vehicle according to claim 1, wherein the mirror base and the main gear are integrally formed of plastic, and the bracket and the first shaft are integrally formed of plastic. Inverted door mirrors