JPS6122049Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a window wiper wiping device having two types of wiping speeds: high and low.

Usually, a windshield wiper wiping device for a vehicle has two types of wiping speeds, low speed and high speed, by switching a switch having a low speed terminal and a high speed terminal, as shown in Japanese Utility Model Publication No. 49-22098, for example. The wiping capacity is adjusted according to the amount of rainfall and driving speed. It is desirable that the wiping range of the wiper blade be as wide as possible, close to the glass holding frame, in order to ensure visibility.The setting of this wiping range depends on the rigidity of the vehicle body to which the windshield wiper wiping device is attached,
It is easy to do this at low speed settings, where there is less increase in wiping amount due to the effects of the rigidity of the link mechanism and the weight of the arms and blades, etc., and the wiping range is the same even when wiping at high speeds as when wiping at low speeds. It is desirable to set the range. Conventionally, when the wiping range is set at a low speed setting, when the wiping range is set at a high speed, the wiping range increases due to the effects of the rigidity of each part and the weight of the arm and blade, and the blade attached to the arm pops out from above the glass surface and holds the glass. When the blade came into contact with the frame, it made an abnormal noise, and it also caused problems such as damaging the blade, deteriorating its wiping performance, and accelerating wear. On the other hand, setting the wiping range when setting the high speed is not only difficult to calculate as it is difficult to calculate the amount of increase in the wiping range due to the influence of the rigidity and weight of each part, but also the wiping range decreases when the speed is set to ensure the required wiping range. There were some problems, such as not being able to do it.

Also, as in Japanese Utility Model Publication No. 49-17883, in order to improve the driver's visibility, it is known that the wiping speed is increased only in the center of the field of view, and the wiping speed is lower at both ends. When applied to a wiping device that has two wiping speeds, low and high, by switching the wiper switch, the wiping range will be the same at low and high speed settings, but one cycle of the wiper blade at high speed settings will be the same. The wiping time for each cycle increases significantly, reducing the wiping ability, making it difficult to maintain sufficient visibility during periods of heavy rainfall or when traveling at high speeds, which requires shortening the wiping time per cycle. If it cannot be secured, there is no point in setting high-speed wiping. Furthermore, if the wiping speed at the center of the field of vision is further increased in order to reduce the increased wiping time, a sudden change in speed will occur within the wiping range, resulting in a lack of smooth wiping and a significant impact on each part of the wiping device. This may cause problems such as durability deterioration due to the impact, or increased operating noise due to the high rotational speed of the wiper motor.

In order to eliminate these problems, the present invention automatically switches to low-speed wiping only in the range from the predetermined position just before the wiper blade reverses to reverse, and automatically switches again to high-speed wiping immediately after reversing when the wiper blade is set to high speed. The purpose is to minimize the increase in the wiping time per cycle of the wiper blade, and to make the wiping range the same at low speed and high speed settings without impairing the wiping ability at high speed settings. It is.

An embodiment of the present invention shown in the drawings will be described below. In FIGS. 1 and 2, 2 is a case of the reduction section of the wiper motor. Inside the case 2, a final gear (worm gear) 4 that meshes with a worm 3 provided on the motor shaft is arranged, and the output shaft 5 is fixed to the final gear 4 by a method such as molding, and a stopper is integrally provided on the upper surface 4a of the gear 4 with a projection 6 projecting in the axial direction and on the axis. Reference numeral 8 denotes a conductive flat cam plate that is coaxially disposed on one surface 4a of the final gear 4 and rotates together with the final gear 4. A pair of mutually symmetrical protrusions that protrude integrally from each other, that is, a pair of protrusions 8a spaced apart by 180 degrees,
8a', and a pair of notches 8b and 8b' formed at mutually symmetrical positions on the same circumference inside the outer circumferential edge, that is, a pair of notches 8b and 8b' spaced apart by 180 degrees. The circumferential centers of the protrusion 8a and the notch 8b and the protrusion 8a' and the notch 8b' coincide with each other.
Make it slightly smaller than the circumferential width of 8b'. Incidentally, the cam plate 8 is arranged by providing a groove in the shape of the cam plate 8 in the final gear 4 so that one surface 4a of the final gear 4 and the upper surface of the cam plate 8 are substantially flush with each other. 9a is a low-speed contact that comes into sliding contact with the projections 8a, 8a', that is, the cam plate 8, as the final gear 4 rotates, and 9b is on the same circumference as the notches 8b, 8b' and slides with the cam plate 8. It is a high-speed contact that contacts, and the low and high-speed contact 9
A, 9b and the cam plate 8 constitute a cam switch 20. The low speed contact 9a and the high speed contact 9b are connected to a connector 10 fixed to the cover 9 of the case 2. A stepped pin 11 is fixed to the cover 9 at a position facing the axis of the final gear 4, so that the stopper 7 receives the thrust of the output shaft 5 by the pin 11. Further, a disk-shaped support member 13 made of an insulating material holding conductive rotating contact plates 12, 12a is loosely fitted around the outer circumference of the pin 11, and the support member 13 is pressed against the cover 9 by a corrugated washer 14. The support member 13 is pivoted to prevent it from shifting due to vibrations, shocks, etc. The support member 13 is provided with a protrusion 13a that can engage with the protrusion piece 6, and the rotation of the final gear 4 is transmitted to the support member 13. 15 is the support member 1
15a is a contact that comes into sliding contact with the rotating contact plate 12 or the rotating contact plate 12a by rotation of 3, and 15a is a contact that makes sliding contact only with the rotating contact plate 12a.
5 and 15a are connected to a connector 16 fixed to the cover 9. Next, FIG. 3 shows the circuit of the present invention, in which the wiper motor 1 includes a power supply brush 1a connected to the positive terminal of a power supply 17, and low-speed and high-speed brushes 1.
b and 1c, and operate the wiper switch 18 to perform low or high speed rotation or stop operation. The wiper switch 18 has two movable pieces 18b and 18c integrally attached to the operating knob 18a, and the low-speed brush 1.
Fixed contacts 18d, 18e, 18f connected to b
and fixed contact 18g connected to high-speed brush 1c.
, a fixed contact 18h connected to the contact 15, a fixed contact 18i connected to the negative pole of the power source 17, a fixed contact 18j connected to the high-speed contact 9b, and a low-speed contact 9.
It has a fixed contact 18k connected to a. When the movable pieces 18b and 18c are at the OFF position, the movable piece 1
8b, the fixed contact 18d and the fixed contact 18h are connected, the fixed contact 18e and the fixed contact 18i are connected at the low speed position Lc, and the movable piece 18 is connected at the high speed position.
Fixed contact 18g and fixed contact 18j are connected via b, and fixed contact 1 is connected via movable piece 18c.
8f and fixed contact 18k are connected. That is, only when the wiper switch 18 is in the high speed position HI, the low and low speed contacts 9a and 9b of the cam switch 20
are connected to the low and high speed brushes 1b and 1c via the wiper switch 18, respectively. Further, the cam plate 8 is connected to the negative electrode of the power source 17, and the cam switch 20 is interposed in the drive circuit when the wiper motor 1 rotates at high speed. Note that the rotating contact plate 12
is connected to the negative terminal of the power supply 17 and the contact 1
5a is connected to the positive electrode of the power source 17.

Next, to explain its operation, wiper switch 1
Turn the stop position OFF by operating the operating knob 18a of 8.
When the wiper motor 1 is moved from the stop position LO to the stop position LO, the wiper motor 1 forms a circuit of the positive electrode of the power source 17 → the brush 1a → the motor 1 → the low-speed brush 1b → the fixed contact 18e → the movable piece 18b → the fixed contact 18i → the negative electrode of the power source 17. A wiper blade 19 shown in FIG. 4, which rotates at a low speed and is connected to an output shaft 5 fixed to the final gear 4 via a link mechanism (not shown), reciprocates and wipes a wiping range L at a low speed. Next, when the wiper switch 18 is turned off, the positive terminal of the power supply 17 → the brush 1a → the motor 1 → the low speed brush 1b →
Fixed contact 18d → Movable piece 18b → Fixed contact 18h
→Contact 15→Rotary contact plate 12→The wiper motor continues to rotate at a low speed due to the negative circuit of the power source 17, and when the wiper blade 19 reaches a predetermined stop position, the contact 15 separates from the rotary contact plate 12a.
Wiper motor 1 → brush 1a → contact 15
a → rotating contact plate 12a → contact 15 → fixed contact 18
A short circuit is formed from h→movable piece 18b→fixed contact 18d→low speed brush 1b, and the wiper motor 1 suddenly stops.

Here, the blade 19 is connected to the output shaft 5 provided on the final gear 4 via a link mechanism or the like, so the wiper blade 19 reciprocates once for each rotation of the final gear 4, and the cam plate 8 is moved to one side of the final gear 4. 4a, and rotates together with the final gear 4, so that the predetermined position of the cam plate 8 and the wiper blade 1
There is a constant relationship with the predetermined position of 9. Therefore, the fourth
As shown in the figure, within the wiping range L from position A to position B, the wiper blade ₁₉ reaches a predetermined position C or D immediately before the other reversal from one reversal position A or B, respectively. , _L3 , the high-speed contact 9b is brought into contact with the cam plate 8, and the wiper blade 19 moves from the predetermined position C or D immediately before one reversal to the reversal position B or A in the wiping range _L2 , _L4. , the high-speed contact 9b is brought into contact with the notch 8b or 8b' to release the contact with the cam plate 8, and the low-speed contact 9a is brought into contact with the protrusion 8a or 8a', that is, the cam plate 8. By setting the shape of the cam plate 8, the cam switch 20 can be automatically sequentially switched between the low-speed contact 9a and the high-speed contact 9b by the rotation of the cam plate 8 caused by the rotation of the final gear 4, and the wiper blade 19 can be switched to each predetermined position. It becomes possible to perform low-speed wiping and high-speed wiping at the wiping position. In other words, when the wiper switch 18 is changed from the stop position OFF to the high speed position, the wiper motor 1 moves from the positive terminal of the power supply 17 to the brush 1a to the motor 1 to the high speed brush 1c to the fixed contact 18g to the movable piece 18b.
→ Fixed contact 18j → High-speed contact 9b → Cam plate 8 → The wiper blade 19 rotates at high speed with the negative electrode circuit of power supply 17 and wipes the area of L ₁ at high speed, and when the notch 8b comes to the position of high-speed contact 9b, the circuit is disconnected, but the low speed contact 9a immediately contacts the protrusion 8a and the power supply 17
positive electrode → brush 1a → motor 1 → low speed brush 1
b → Fixed contact 18f → Movable piece 18c → Fixed contact 1
A circuit of 8k→low speed contact 9a→protrusion 8a→negative electrode of power source 17 is formed, the motor 1 rotates at low speed, and the wiper blade 19 wipes the range _L2 at low speed.
Low speed contact 9a at reverse position B of wiper blade 19
is separated from the protrusion 8a, the high-speed contact 9b immediately contacts the cam plate 8, the motor 1 rotates at high speed, the wiper blade 19 wipes the area _L3 at high speed, and the notch 8
When b' comes to the position of high speed contact 9b, the circuit is disconnected, but immediately the low speed contact 9a comes into contact with protrusion 8a', motor 1 rotates at low speed, wiper blade 19 wipes the area L ₄ at low speed, and then Repeat the same action.
Although the circuit is momentarily disconnected when switching the contacts, there is no problem because the final gear 4 rotates due to inertia.

As described above, according to the present invention, when the wiper blade is set at high speed, the wiper blade has a wiping range from a predetermined position C or D immediately before reversal to reversal position B or A.
It automatically switches to low-speed wiping only when in L ₂ or L ₄ , and automatically switches back to high-speed wiping immediately after reversing, minimizing the increase in wiping time per cycle of the wiper blade. Therefore, the wiping range of the wiper blade can be made the same between the low speed setting and the high speed setting without impairing the wiping ability during the high speed setting. In addition, the cam switch is composed of a flat cam plate disposed coaxially on one surface of the final gear, and low and high speed contacts that come into sliding contact with and separate from the cam plate, so they are arranged facing each other. The structure is simpler and more compact than a cam switch in which a movable contact disposed between a pair of stationary contacts is moved by rotation of a cam plate to switch the contacts.

[Brief explanation of the drawing]

Figures 1 to 3 show an example of the implementation of the present invention, with Figure 1 being a partially cutaway side view and Figure 2 being a partially cutaway side view.
FIG. 3 is a circuit diagram, and FIG. 4 is an explanatory diagram showing the wiping state of the wiper blade. 1...Wiper switch, 1b...Low speed brush, 1c...High speed brush, 4...Final gear, 8
...Cam plate, 8a, 8a'...Protrusion, 8b, 8b'...
...notch, 9a...low speed contact, 9b...high speed contact, 18...wiper switch, 19...wiper blade, 20...cam switch.

Claims (1)

[Scope of utility model registration request] In a window wiper wiping device in which the rotation of the final gear of a wiper motor having a low-speed brush and a high-speed brush is transmitted to the wiper blade via a link mechanism, etc., and two types of wiping speed, high or low, can be selected by operating a wiper switch. , low and high speed contacts which are respectively connected to the low and high speed brushes via the wiper switch only when the wiper switch is in the high speed position, and which are disposed coaxially on one surface of the final gear and are integral with the final gear. and a conductive flat cam plate that rotates to slide into and away from the low and high speed contacts, respectively, and this cam plate rotates the wiper blade from a predetermined position C or D immediately before reversal to reversal position B. Or the dispelling range leading to A
It separates from the high-speed contact only when it is at L ₂ or L ₄ , and at symmetrical positions on the same circumference inside the outer periphery of the cam plate in order to come into sliding contact with the high-speed contact in other wiping ranges. Formed 1
A pair of notches and a wiper blade are provided in the wiping range.
a pair of mutually symmetrical protrusions that protrude integrally from the outer peripheral edge of the cam plate in the radial direction so as to come into sliding contact with the low speed contact only when the cam plate is at L ₂ or L ₄ ; A windshield wiper wiping device characterized in that a cam switch is constituted by a contact point and a high speed contact point, and the cam switch is interposed in a drive circuit when the wiper motor rotates at high speed.