JPH045573B2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a wiper device having a wide wiping area, and in particular to a wiper device in which a casing having a torque transmission means therein is rotationally driven by a drive shaft serving as an input shaft. ,
The present invention relates to a wiper device in which an input side member of a torque transmission means is connected to a fixed sleeve, and a wiper arm is connected to an output shaft of the torque transmission means that eccentrically projects from the casing.

<Prior art> In a normal wiper device, the wiper blade is attached to the tip of a swinging wiper arm, so the wiping area is fan-shaped, whereas the windshield of a vehicle is generally square. There is a problem in that the ratio of the wiped area to the total area of the windshield is small, which may limit the driver's field of view in the vehicle. Therefore,
As taught in Japanese Patent Publication No. 47-22531, Japanese Patent Publication No. 47-46368, or Japanese Patent Publication No. 47-49739, a casing containing three serially meshing gears is rotated in both directions of rotation. The first gear, which is dynamically driven and supported coaxially with respect to the rotational axis of the casing among the three gears, is fixed, and the base of the wiper arm of the third gear is connected to impart trochoidal movement to the wiper blade. A technique has been proposed for increasing the area to be wiped by wiping.

Although the use of such a wiper device has the advantage of increasing the wiping area, the angular velocity of the wiper arm is not constant or sinusoidal, but changes in a complex manner, especially when the wiper arm is located between the left and right ends and the center. At this time, the angular velocity of the wiper arm decreases, which causes a visual discomfort. Therefore, Japanese Patent Publication No. 47-46368 proposes a technique for solving this problem by using an eccentric gear to drive the casing at an inconstant angular velocity. However, since an eccentric gear is used, there is a problem that the manufacturing process becomes complicated and the manufacturing cost increases.

<Problems to be Solved by the Invention> In view of the problems of the prior art, the main object of the present invention is to provide a wiper device of the above type that is improved so as to eliminate the discomfort caused by uneven speed of the wiper arm. It's about doing.

<Means for Solving the Problems> According to the present invention, this object includes a fixed sleeve, a drive unit, and an input shaft that is rotatably driven in both directions by the drive unit within the fixed sleeve. a casing integrally coupled to the input shaft; an input member rotatably supported within the casing relative to the casing and integrally coupled to the fixed sleeve; and a base portion of the wiper arm. In the wiper device, the wiper device has an output shaft that protrudes from the casing and is connected to the input member via a torque transmission means, and the drive unit includes a drive source and a drive unit that is rotatably driven by the drive source. a transmission member rotatably driven coaxially with respect to the support member with a gear ratio of -1; and an eccentric supported eccentrically and rotatably with respect to the support member. a shaft; an arm extending from the eccentric shaft and having a free end engaging the transmission member so as to rotate the eccentric shaft; This is achieved by providing a wiper device characterized by comprising a link mechanism for converting the wiper device into a wiper device.

<Operation> By assembling the eccentric shaft so that it can rotate relative to the rotation axis of the support member, and engaging the eccentric shaft with a transmission member that rotates coaxially with the support member and at the same speed in the opposite direction, the support member can be rotated. When driven to rotate at a constant speed, the center of the eccentric shaft performs non-uniform rotational motion while drawing an elliptical orbit. By adapting the characteristics to the characteristics of a specific trochoid wiper device, it is possible to eliminate the discomfort caused by the speed unevenness of the wiper arm as described above.

<Examples> Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows a wiper device according to the invention.
The base plate 2 is fixed to a fixing member 1 of the vehicle body shown by phantom lines with a screw 3 screwed into a screw hole 2a formed in the base plate. Although only one screw 3 is shown in FIG. 1, in reality a required number of screws 3 are used. A pivot shaft 4 is press-fitted into the left end of this board 2 in FIG. The sector gear 5 is prevented from coming off by a snap spring 4a. A joint ball 7 is fixed to the sector gear 5 and is to be engaged with a free end of a connecting rod 82 (FIG. 4) that is reciprocated by a motor (not shown).

At the right end of the board 2 in FIG.
is integrally formed and inserted into a hole 1a formed in the fixing member 1. In the center hole 8c of the sleeve 8, an input shaft 10 is rotatably supported via a pair of sliding bearings 9. A pinion gear 11 that meshes with the sector gear 5 is fixed to the lower end of the input shaft 10 in FIG. 1 by being press-fitted and brazed. The upper end of the input shaft 10 in FIG. 1 and the upper end of the sleeve 8 in FIG. The diagram will be explained in detail.

This gearbox 12 has a pair of casing parts 13 forming a generally flat triangular casing.
a, 13b. A relatively large-diameter hole 15 is formed in the lower casing portion 13b in FIG. 1, and an annular rubber 16 is integrally fixed to the outer periphery of the hole 15. The sleeve 8 of the board 2 is fitted into this hole 15 via an O-ring 14, and the free end of the sleeve 8 is chamfered on two sides as shown by the reference numeral 25. A complementary central hole 23 opened in the center of the first gear 22 is fitted. In addition, the first gear 22 and the sleeve 8
A through hole 22a and a threaded hole 8b are formed at diagonal positions in the axial shoulder surface 8a adjacent to the two-chamfered portion 25, and the hexagonal socket bolt 24 is inserted into these. They are screwed together. Further, the input shaft 10 is provided with a tapered serration portion 19 at its upper portion in FIG. The screw portion 20 at the upper end passes through a center hole 42 of a disc-shaped cover 41 (to be described later) that covers the casing portion 13a, and a cap nut 21 is screwed into the cover 41 to connect the cover 41 to the casing portion 13a.
At the same time, the casing portion 13a is integrally connected to the input shaft 10.

As best shown in particular in FIG.
The first gear 26 is rotatably supported via a pivot 27 supported between a bracket 28 installed on the lower casing portion 13b so as to cross the center of the upper surface of the gear 26 in FIG. It meshes with the gear 22 of. In addition, codes 29 and 40 are respectively
Screws for fixing the bracket 28 to the lower casing part 13b, both casing parts 13a, 1
The screws connecting 3b to each other are shown. Furthermore,
The third gear 30 meshes with the second gear 26, and the serration portion 33 of the output shaft 32 is press-fitted into the center hole 31 of the third gear.
A snap ring 35 fitted in an annular groove of the output shaft 32 is an annular protrusion 13c that protrudes from the upper casing portion 13a concentrically and integrally with respect to the output shaft 32 so as to surround the output shaft 32. , and the upper end surface of the gear 30 contacts the lower surface of the casing portion 13a in FIG. 1 via the wave washer 44, so that the output shaft 32
is supported so as not to be displaced in the axial direction but to be rotatable. A stepped sleeve 36, which may be made of rubber, is fitted onto the outer periphery of the annular projection 13c and a portion of the upper end projection of the output shaft 32 in FIG. 1 for sealing from the outside. Additionally, an O-ring 34 is provided around the protrusion of the output shaft 32 to seal the inside of the casing from the outside. A tapered serration portion 37 and a threaded portion 38 are formed at the upper end of the output shaft 32 in FIG. The wiper arm is held by a nut screwed into the wiper arm.

As described above, the rotational force input from the first gear 22 serving as an input member is transmitted to the output shaft 32 via the second gear 26 and the third gear 30 serving as torque transmitting members.

A through hole 39 is formed in the vicinity of the corresponding hole 18 in the upper casing portion 13a, and this is because when the casing portion 13a is rotated relative to the first gear 22, the through hole 39 opens into the head of the bolt 24. The bolt 24 is inserted through the through hole 39, passes through the hole 22a, and then passes through the screw hole 8b.
and screw 24.
After screwing, a lid 39a made of rubber for a good seal is fitted. At this time, the bolt 24 can be fastened by engaging the hex wrench with the head of the bolt 24 through the through hole 39. Also,
Both casing parts 13 for the first gear 22
By appropriately rotating a and 13b, two bolts 24 can be fastened using one hole 39.

As clearly shown in FIG. 4, the disc-shaped cover 41 is made of a tray-shaped thin plate member with an open bottom in FIG. It has a hole 42 and an eccentric hole 43 into which the annular protrusion 13c surrounding the output shaft 32 is inserted. Therefore, although the casing portions 13a, 13b are rotationally driven eccentrically by the input shaft 10, the casing portions 13a, 13b
The disk-shaped cover that covers the holder is rotated concentrically, so that no unsightly eccentric movement is visible from the outside, and the risk of biting foreign objects is also eliminated.

FIG. 5 shows a schematic structure for driving the sector gear 5 via the joint ball 7. As shown in FIG. That is, the motor unit 6 as a drive source
A free end of a connecting rod 82 driven by a drive unit 62 having a drive unit 3 is connected to the joint ball 7 of the sector gear 5 to form a ball joint 45. On the other hand, the output shaft 3 of the gearbox 12
A base end of a wiper arm 83 is fixed to the free end of the wiper arm 83, and the free end of the wiper arm 83 is connected to an intermediate portion of a wiper blade 84.

As shown in FIGS. 8 and 9, a drive shaft 64 is provided inside the drive unit 62 and is connected to the output shaft of the motor unit 63 and has worms 65 and 66 facing in opposite directions. ing. The worm 66 is connected to the casing 67 by a pivot 68.
It meshes with a gear 69 which is rotatably supported via. Further, a support shaft 71 as a support member having an axis parallel to the pivot shaft 68 is also rotatably supported by the casing 67.
A gear 72 formed integrally and coaxially with the gear 69 meshes with a gear 70 formed integrally and coaxially with the gear 69 . A gear 74 serving as a transmission member that meshes with the worm 65 is rotatably supported on a short shaft portion 73 of the support shaft 71 that projects downward from the gear 72 in FIG. Further, a through hole 71a facing in the axial direction is provided at a position eccentric to the central axis of the support shaft 71, and an eccentric shaft 76 is rotatably received inside the through hole 71a. This eccentric shaft 7
6, an arm 77 projecting outward in the radial direction is fixed to the lower end in FIG. However, the sleeve 7 is inserted into the slot 75 opened in the radial direction of the gear 74.
Accepted via 9. Furthermore, a second arm 80 is fixed to the upper end of the eccentric shaft 76 in FIG. has been done.

As described above, the rotational movement of the eccentric shaft 8 is transmitted to the input shaft 1 via the second arm 80, the connecting rod 82, the sector gear 5, and the pinion gear 11, which form a link mechanism.
It is converted into a reciprocating rocking motion of 0.

Next, the operation of the wiper device according to the present invention will be explained with reference to FIGS. 5 to 9.

When the drive shaft 64 is driven by the motor unit 63, the support shaft 71 rotates at a constant speed via the gears 69, 70, and 72. Further, the gear 74 is also rotationally driven by the worm 65.
gears 69, 70, 72, 74 and worm 65,
By appropriately determining the relationship of 66, gears 72 and 74 can rotate in opposite directions at the same rotational speed.
That is, it is rotatably driven with a gear ratio of -1. Therefore, as the gear 74 rotates,
The eccentric shaft 76 is rotationally driven through the slot 75, pin 78, and arm 77, but at the same time, the support shaft 71, which is integral with the gear 72, is rotationally driven in the opposite direction.
The arm 80 fixed to the eccentric shaft 76 has its free end drawing an elliptical orbit, and is driven to rotate at an inconstant speed as will be described later.

As shown in FIG.
3 is in one end position, the arm 80 is in a position generally aligned with the connecting rod 82. The arm 80 is rotationally driven, and the wiper arm 83 moves into the wiping area 6 of the windshield, as shown in FIG.
When moving at a relatively low speed above 0, the arm 80
is at a position where the angle advances by a certain angle between 0° and 90°. When the arm 80 further rotates to the 90° position, the wiper arm 83 reaches approximately the center of the wiping area 60, as shown in FIG.

FIG. 10 shows that the effective length A of the arm 80 is 46 mm, the effective length B of the arm 77 is 22 mm, the distance C between the rotation center of the sector gear 5 and the ball joint 45 is 62 mm, and the eccentricity E of the eccentric shaft 76 is 4 mm. The angular velocity of the sector gear 5 when the effective length l of the connecting rod 82 is 373 mm is
A comparison is shown with a conventional simple crank mechanism. As shown by the solid line, when an elliptical motor like the one used in this example is used, the angular velocity takes a maximum value around θ=90°, so for example, as shown in FIG. As shown in FIG. 2, when the wiper arm 83 is located between the center and the end when the trochoid gear is used, and its angular velocity becomes small, the driving speed by the elliptical motor increases, and the wiper arm 83
The unevenness of the angular velocity will be alleviated.

<Effects of the Invention> As described above, according to the present invention, the unevenness of the angular velocity of the wiper arm can be effectively suppressed, and the wiping range of the wiper can be expanded, and the effects are extremely large.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a main part of a wiper device according to the present invention. FIG. 2 is a partially cutaway plan view of the gearbox shown in FIG. 1. FIG. 3 is a bottom view of the gearbox of FIG. 2. FIG. 4 is an exploded perspective view of the wiper device shown in FIG. 1. FIG. 5 is an explanatory diagram schematically showing the overall structure of the wiper device according to the present invention. 6 and 7 are views similar to FIG. 5 showing the wiper arm in different angular positions. FIG. 8 is a longitudinal sectional view showing the main parts of the drive unit used in FIGS. 5 to 7. FIG. 9 is a schematic cross-sectional view taken along the - line in FIG. 8. FIG. 10 is a graph showing the angular velocity of the sector gear when the elliptical motor drive unit shown in FIGS. 8 and 9 is used in comparison with when a conventional simple crank mechanism is used. 1... Fixing member, 1a... Hole, 2... Substrate, 2
a...Screw hole, 3...Screw, 4...Pivot, 4a...
...Snat spring, 5...Sector gear, 6...Slide bearing, 7...Joint ball, 8...Sleeve, 8a...Shoulder surface, 8b...Threaded hole, 8c...Center hole, 9...Slide bearing, 10...Input shaft, 11...
...Pinion gear, 12...Gear box, 13
a, 13b...casing part, 13c...annular protrusion, 14...O ring, 15...hole, 16...
Annular rubber, 18... Corresponding hole, 19... Serration part, 20... Threaded part, 21... Cap nut,
22...first gear, 22a...through hole, 23...
...Center hole, 24...Hexagon socket head bolt, 25...Double chamfered part, 26...Gear, 27...Pivot, 28...
...Bracket, 29...Screw, 30...Gear, 3
1... Center hole, 32... Output shaft, 33... Serration portion, 34... O-ring, 35... Snap spring, 36... Stepped sleeve, 37... Serration portion, 38... Threaded portion, 39... ...through hole,
39a... Lid, 40... Screw, 41... Disc-shaped cover, 42... Center hole, 43... Eccentric hole, 44...
... Wave washer, 45 ... Ball joint, 60 ... Wiping area, 62 ... Drive unit,
63...Motor unit, 64...Drive shaft, 6
5, 66...Worm, 67...Casing, 6
8... Pivot, 69, 70... Gear, 71... Support shaft, 71a... Through hole, 72... Gear (support member), 73... Short shaft, 74... Gear (transmission member),
75...Slot, 76...Eccentric shaft, 77...Arm, 78...Pin, 79...Sleeve, 80...
...Arm, 81...Ball joint, 82...
Connecting rod, 83... wiper arm, 84... wiper blade.

Claims (1)

[Scope of Claims] 1. A fixed sleeve 8, a drive unit 62, and an input shaft 10 reciprocatingly driven in both directions by the drive unit 62 within the fixed sleeve 8.
casings 13a, 13b integrally coupled to the input shaft 10, and casings 13a, 13;
an input member 22 rotatably supported within the casings 13a, 13b and integrally connected to the fixed sleeve 8; and a wiper arm 8.
said casing 13 to be connected to the base of 3.
In the wiper device having an output shaft 32 protruding from the input members 22a and 13b and connected to the input member 22 via torque transmission means 26 and 30, the drive unit 62 includes a drive source 63 and a drive source 63. The support member 71 is rotationally driven by
and -1 coaxially with respect to the support member 71.
A transmission member 74 that is rotationally driven with a gear ratio of
an eccentric shaft 76 eccentrically and rotatably supported with respect to the support member 71;
an arm 77 extending from the eccentric shaft 76 and having its free end engaged with the transmission member 74 so as to rotate the input shaft 10; A wiper device comprising link mechanisms 80, 82, 5, and 11 for conversion.