JPS6171254A - Wiper arm load controlling device - Google Patents

Abstract

PURPOSE:To prevent noise when a wiper is reversed by driving a hydraulic cylinder and reducing the load of an arm which is applied to a blade in the reversed position of said wiper. CONSTITUTION:When a blade rotates in the normal direction, pressure is not applied to an operating fluid in a driving side hydraulic cylinder 50. Accordingly, since the oil pressure in a driven side hydraulic cylinder 25 is also low, a wiper arm 22 is energized clockwise by means of a spring 29. Thereby, the blade is slidingly brought in contact with a front glass being pressed against it. When the blade arrives at the reversed position, the piston 53 of the hydraulic cylinder 50 is operated by means of a cam 43 which is interlocked with the rotation of a driving shaft 40, via a rod 56, and pressure is applied to the operating oil in the hydraulic cylinder 50. This pressure is transmitted to the driven side hydraulic cylinder 25. Thereby, a piston 27 is operated pushing out a rod 30 to rotate the wiper arm 22 counterclockwise. As a result, the load to the arm 22 is reduced, decreasing pressing force of the blade to the front glass. circuit, 8: T.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a wiper arm load control device that prevents noise when the wiper of a vehicle is reversed.

[Technical background of the invention and its problems]

In conventional wipers, in order to keep the blade always in sliding contact with the glass surface, a tension spring is installed between the arm head and the wiper arm, and arm load is applied to press the blade against the glass surface.

However, in the case where the arm load is applied by a tension spring, the arm load is constant, so there is a problem in that reversal noise is generated when the wiper is reversed.

(Objective of the Invention) The present invention was made based on the above circumstances, and an object thereof is to provide a wiper arm load control device that reduces the arm load when the wiper is reversed and prevents reversal noise. That is.

(Summary of the Invention) In order to achieve the above object, the present invention rotatably attaches a driven side hydraulic cylinder to an arm head that is reversely driven by a wiper motor, and connects a tension rod connected to a piston of this driven side hydraulic cylinder to the wiper arm. A cam is attached to the drive shaft that is rotatably supported by the wiper motor and rotates in synchronization with the wiper motor, and a pressure rod connected to the piston of the drive side hydraulic cylinder is brought into contact with this cam, thereby connecting the driven side hydraulic cylinder and the drive side hydraulic pressure. The cylinders are connected through a hydraulic pipe line filled with hydraulic oil, and the rotation of the motor causes the profile of the cam to move the pressing rod at the wiper reversal position to operate the piston of the drive-side hydraulic cylinder;
The hydraulic pressure generated by the operation of the piston is transmitted to the piston of the driven hydraulic cylinder through the hydraulic conduit, and the tension rod is moved by the piston, thereby reducing the arm load applied to the blade.

[Embodiments of the invention]

The present invention will be explained below based on an embodiment shown in FIGS. 1 to 3.

FIG. 1 shows a vehicle equipped with the arm load control device of the present invention, where 1 is a front wheel, 2 is a rear wheel, 3 is a bonnet, and 4 is a windshield. A driver's seat wiper 5 and a passenger's seat wiper 6 are provided on the front surface of the windshield 4. The driver's side wiper 5 and the passenger's side wiper 6 each have a blade 12,13. Further, the engine room covered by the bonnet 3 is provided with a wiper motor 7, a negative pressure controller 8 as an actuator, and a junction box 9, which will be described later. Note that 10 and 11 are hydraulic conduits connecting the drive side hydraulic cylinder and the driven side hydraulic cylinder of the driver's seat wiper 5 and the passenger seat wiper 6, respectively.

Details of the arm load control device will be explained with reference to FIGS. 2 and 3. Note that FIG. 2 mainly shows the arm load control device related to the driver's seat wiper 5, and the arm load control device related to the passenger seat wiper 6 is the same as that on the driver's seat, so a description thereof will be omitted.

Reference numeral 20 denotes an arm piece, and the blade 12 shown in FIG. 1 is attached to this arm piece 20, and this arm piece 20 is caulked to a wiper arm 22. The wiper arm 22 is rotatably connected to the arm head 23 by a rivet 24.

The arm head 23 is reversely driven within a predetermined angle by the wiper motor 7.

A driven hydraulic cylinder 25 is mounted between the wiper arm 22 and the arm head 23 . The driven side hydraulic cylinder 25 includes a cylinder case 26 and a piston 27.
, a bellows 28, a compression coil spring 29, and a tension rod 30 connected to the piston 27, forming a so-called bellows type hydraulic cylinder. In this bellows type hydraulic cylinder 25, when the hydraulic pressure of the hydraulic oil filled in the cylinder case 26 is increased, the piston 27 and the bellows 28 are pushed against the biasing force of the compression coil spring 29, and the tension rod 30 is pushed. It is designed to operate in the direction of extension.

The cylinder case 26 is rotatably attached to a pin 31 driven into the arm head 23 by a plate 32 and machine screws 33. Further, a screw 34 is carved at the tip of the tension rod 30, and this screw 34
Joint 35 is screwed into.

The joint 35 is rotatably connected to a pin 36 driven into the wiper arm 22 by a plate 37 and a small screw 38. In the cylinder case 26,
A pipe joint 39 is connected to the pipe joint 39, and one end of the hydraulic pipe line 10 is connected to the pipe joint 39.

On the other hand, the wiper motor 7 is provided with a drive shaft 40, as shown in FIG. This drive shaft 40 is formed by extending the worm wheel shaft 41 of the wiper motor 7, and cams 43 and 44 are attached to this drive shaft 40 via a key 42.

These cams 43, 44 rotate integrally with the drive shaft 40, but are mounted so as to be able to slide in the axial direction with respect to the drive shaft 40. These cams 43 and 44 are pressed upward in the drawing by a compression coil spring 45. The cams 43 and 44 have a tapered shape where the lower side is thinner than the upper side, and each has a diameter of 180 mm.
At a shifted position, a protrusion 46a as shown in FIG.
46b, 47a, and 47b.

The drive shaft 40 is surrounded by a shaft case 48 fixed to the wiper motor 7, and the shaft case 48 includes a drive-side hydraulic cylinder 50 for the driver's seat wiper and a drive-side hydraulic cylinder 51 for the passenger's seat wiper. connected.

The driving side hydraulic cylinder 50 for the driver's seat side wiper is composed of a cylinder case 52, a piston 53, a bellows 54, a compression coil spring 55, and a pressing rod 56 connected to the piston 53. It forms a bellows type hydraulic cylinder.

The pressing rod 56 is a compression coil spring 55.
The cam 43 is constantly pressed against the side surface of the one cam 43 under the urging force of the cam 43 . Therefore, when the cam 43 is rotated by the rotation of the drive shaft 40, the profile of the cam 43, that is, the protrusions 46a and 46b, causes the pressing rod 5 to be rotated.
6, and this pressing rod 56 operates the piston 53 against the biasing force of the compression coil spring 55. The operation of the piston 53 extends the bellows 54 and compresses the hydraulic oil filled in the cylinder case 52.

A pipe joint 57 is connected to the cylinder case 52, and the other end of the hydraulic pipe line 10 is connected to the pipe joint 57. Therefore, the pressure of the hydraulic oil pressurized in the cylinder case 52 of the driver side wiper drive side hydraulic cylinder 50 is transmitted to the hydraulic oil in the cylinder case 26 of the driven side hydraulic cylinder 25 through the hydraulic pipe line 10. .

Note that the structure of the drive-side hydraulic cylinder 51 for the passenger seat wiper is also similar to the above drive-side hydraulic cylinder 50 for the driver seat wiper, and the same members will be described with the same number and the addition of the symbol a. However, the pressing rod 56a is always pushed against the other cam 44 by the urging force of the compression coil spring 55a.
is in contact with the side of the

Therefore, due to the rotation of the drive shaft 40, the other cam 4
4 is rotated, the protrusions 47a of this cam 44, 4
7b pushes the pressing rod 56a, and this pressing rod 56a compresses the piston 53a by the coil spring 55a.
actuate against the urging force of. The operation of the piston 53a extends the bellows 54a and compresses the hydraulic oil filled in the cylinder case 52a. and,
The hydraulic pipe line 11 for the passenger seat wiper is connected to the cylinder case 52a via a pipe joint 57a.

In addition, the protrusions 46a, 46b of each cam 43, 44,
47a.

The timing for pushing the pressure rods 56, 56a by the blades 47b is set to be when the blades 12, 13 reach the reversal position.

A negative pressure controller 8 as an actuator is connected to the shaft case 48 . The negative pressure controller 8 will be explained with reference to FIG. 2. Reference numeral 60 is a diaphragm housing connected to the shaft case 48, and a diaphragm 61 is deformably housed within the diaphragm housing 60. The press rod 6 is attached to the diaphragm 61.
2 is connected to the press rod 62, and a sliding ring 63 is connected to the lower end of the press rod 62 in the drawing. activity ring 63
is movable in the axial direction of the drive shaft 40, and the lower surface of this sliding ring 63 is in contact with the upper surface of the cam 44.

Therefore, due to the operation of the diaphragm 61, the sliding ring 6
3 is moved in the axial direction of the drive shaft 40, the cam 43°4
4 also moves in the axial direction. The position of the push rod 56.56a is therefore controlled by the tapered cam profile. Note that a bellows 64 is attached to the press rod 62.

Negative pressure 65 within the diaphragm housing 60 is communicated with a negative pressure control chamber 70 via a negative pressure introduction pipe 66. The negative pressure control chamber 70 is composed of a chamber body 71 attached to the vehicle body and a cap 72, and the cap 72 has a negative pressure inlet body 7 connected to an engine intake manifold (not shown), etc.
3 is connected. The negative pressure control chamber 70 includes a negative pressure chamber 65 in the diaphragm housing 60.
A solenoid valve 74 for controlling the amount of negative pressure is incorporated. This solenoid valve 74 is operated by an electronic control unit (ECU>75). The electromagnetic valve 74 is controlled in response to the detection signal.

A junction box 9 is installed in the middle of the hydraulic conduit 10. Junction box 9 is
Box body 90, box cap 91, piston 9
2. It consists of a manual bushing rod 93, a bellows 94, and a compression coil spring 95, and the threaded part formed on the manual bushing rod 93 is screwed into the threaded part of the box cap 91. Therefore, when the manual bushing rod 93 is turned, the manual bushing rod 93 is screwed forward and backward. When the manual bushing rod 93 enters, the piston 92 is pushed, so that the hydraulic oil in the box body 90 is pressurized.

Arm load control with this kind of configuration! The operation of the II device will be explained.

When the hydraulic oil is not pressurized in the drive side hydraulic cylinder 50, the oil pressure in the driven side hydraulic cylinder 25 is also low. As a result of the retraction force, the wiper arm 22 is being pulled clockwise in FIG. For this reason, blade 1
2 is pressed against the windshield 4 and comes into sliding contact. This state is when the blade 12 rotates back and forth.

When the blade 12 reaches the reversal position, it operates as follows. That is, the rotation of the drive shaft 40 causes the cams 43 and 44 to rotate.
Since the cams 43 and 44 are rotated together, these cams 43 and 44 are rotated at the timing when the blade 12 reaches the reverse position.
Protrusions 46a, 46b, 47a formed on.

47b has just come to a position opposite the pressing rod 56, 56a. Therefore, the protrusion 46a of the cam 43,
46b pushes the pressure rod 56, the piston 53 and the bellows 54 are actuated, and the hydraulic oil in the cylinder case 52 is pushed. Therefore, the drive side hydraulic cylinder 50
The hydraulic oil inside is pressurized. This pressure is transmitted to the driven hydraulic cylinder 25 through the hydraulic line 10.

When the hydraulic pressure in the driven hydraulic cylinder 25 is increased, the piston 27 and the bellows 28 of the driven hydraulic cylinder 25 are pushed to push out the tension rod 30, so the wiper arm 22 moves counterclockwise in FIG. rotated,
The force pressing the blade 12 against the windshield 4, that is, the arm load, is reduced. Therefore, generation of reversal noise when the blade 12 is reversed is prevented.

On the other hand, when driving at high speed, the electronic controller (EC(J) 75 is activated by signals from the vehicle speed sensor 76 and the potentiometer 77 that detects the positions of the cams 43 and 44.
This electronic controller 75 controls the solenoid valve 74.

By operating the solenoid valve 74, the negative pressure control chamber 7
The amount of negative pressure introduced into the negative pressure chamber 65 of the diaphragm housing 60 from zero is controlled.

When the vehicle speed is low, the negative pressure in the negative pressure chamber 65 of the diaphragm housing 60 is increased, and when the vehicle speed is high, the negative pressure in the negative pressure chamber 65 of the diaphragm housing 60 is controlled to be decreased. ing. When the negative pressure inside the negative pressure chamber 65 is large, the amount of downward deflection of the diaphragm 61 as shown in the figure becomes large, and the press roller 2 is moved downward greatly. is moved downward in the axial direction against the urging force of.

In this case, the large diameter portions of the tapered cams 43, 44 abut against the pressing rods 56, 56a. Therefore, the pressing rod 56 is moved largely to the left, and the arm load is reduced.

Conversely, when the negative pressure in the negative pressure v65 is small, the downward deflection of the diaphragm 61 as shown in the figure also becomes small, and the downward movement of the press rod 62 also becomes small.
The axial downward movement of is small. In this case, the small diameter portion of the tapered cam 43.44 is connected to the pressing port rad 56.56a.
, the amount of movement of the pressing rod 56 to the left decreases, and the arm load increases.

For this reason, when traveling in a erratic state, the negative pressure in the negative pressure amount 65 is controlled to be small, and the small diameter portions of the tapered cams 43 and 44 are brought into contact with the pressing rods 56 and 56a. 56 to the left is reduced, and the arm load is increased. As a result, the blades 12 are prevented from floating due to the pressure of the wind hitting the windshield 4 during high-speed driving.

The junction box 9 is for setting the initial arm load, and when the manual bushing rod 93 enters, the piston 92 is pushed, so that the hydraulic oil in the box body 90 is pressurized. This pressure increase is transmitted to the driven hydraulic cylinder 25 through the hydraulic conduit 10, increasing the hydraulic pressure of the driven hydraulic cylinder 25 and reducing the arm load. Furthermore, when the manual bushing rod 93 is moved backward, the hydraulic oil pressure within the box body 90 is reduced, and this pressure is transmitted to the driven side hydraulic cylinder 25 through the hydraulic line 10, lowering the oil pressure of the driven side hydraulic cylinder 25. Therefore, the arm load increases.

Next, a second embodiment shown in FIG. 4 will be described.

In the first embodiment described above, the diaphragm housing 60 as an actuator is attached to the shaft case 48,
Although the cams 43 and 44 are actuated in the axial direction by the diaphragm 61, in the case of the second embodiment, a diaphragm housing 100 as an actuator is attached to the junction box 9. A bushing rod 102 connected to a diaphragm 101 provided in a diaphragm housing 100 is connected to a junction box body 9.
It is connected to the piston 92 in the 0. The negative pressure v103 is communicated with the negative pressure control chamber 70 shown in FIG. 2 through a negative pressure introduction pipe 104.

According to such a configuration, when negative pressure is introduced into the negative pressure amount 103 through the negative pressure introduction pipe 104, the diaphragm 101 is bent to the left in FIG. 4, and the bushing rod 102 pushes the piston 92 accordingly. Therefore, the hydraulic oil in the junction box body 90 is pressurized, and this pressure is transmitted to the driven hydraulic cylinder 25 through the hydraulic line 10, increasing the hydraulic pressure in the driven hydraulic cylinder 25 and reducing the arm load.

The amount of negative pressure in the negative pressure air 103 is determined by the electronic controller 75 in FIG.
Since the solenoid valve 74 adjusts the arm load to a smaller value when the vehicle speed is high, it is possible to prevent the blade 12 from floating by increasing the arm load according to the vehicle speed.

In addition, in the case of such a second embodiment, the cams 43° 44
Since there is no need to slide the cam in the axial direction of the drive shaft 40, the number of parts can be reduced, and the cams 43 and 44 are also
Since there is no need to create a three-dimensional tapered shape as in the embodiment, processing becomes easier.

Furthermore, a third embodiment will be explained based on FIG. 5.

In the first and second embodiments, the negative pressure controller 8 was used as the actuator, but in the third embodiment, a step motor 200 is used as the actuator. That is, the electronic controller 202 is moved by a pulse signal from the vehicle speed sensor 201, and the step motor 200 is rotated by the electronic controller 202. A pinion 203 of the step motor 200 is engaged with a rack 205 cut at one end of a bushing rod 204, and the bushing rod 204 moves in the axial direction according to the rotation angle of the step motor 200. Bush rod 204 is connected to piston 92 of junction box 9.

Therefore, the hydraulic oil in the junction box body 90 is pressurized according to the rotation angle of the step motor 200, and this pressure is transferred to the driven side hydraulic cylinder 25 through the hydraulic pipe line 10.
The hydraulic pressure in the driven hydraulic cylinder 25 is increased to reduce the arm load. Therefore, if the amount of axial movement of the bushing rod 204 is reduced when the vehicle speed is high, the arm load increases and the blade 12 can be prevented from floating.

The step motor may be used instead of the negative pressure controller 8 of FIG. 2 to operate the cams 43, 44 in the axial direction of the drive shaft 40.

In each embodiment, the drive side hydraulic cylinder 51.5
1a, F3, and the driven side hydraulic cylinder 25 are used as bellows-type hydraulic cylinders.This type of bellows-type hydraulic cylinder causes large pressure fluctuations due to the bellows even with a small stroke of the piston, so the operation is quick. It has the advantage of However, the present invention is not limited to this, and a normal hydraulic cylinder may be used.

[Effects of the Invention] As described above, according to the present invention, the pressure rod is moved by the profile of the cam at the wiper reversal position by the rotation of the wiper motor, and the piston of the drive-side hydraulic cylinder is actuated, and the hydraulic pressure due to the operation of the piston is Since the force is transmitted to the piston of the driven side hydraulic cylinder through the hydraulic conduit and the tension rod is moved by the piston to reduce the arm load applied to the blade, reversal noise when the wiper is reversed is prevented.

[Brief explanation of the drawing]

1 to 3 show a first embodiment of the present invention.
The figure is a layout diagram of the vehicle, Figure 2 is an overall configuration diagram, and Figure 3 is a diagram of the overall configuration.
The figure is a sectional view taken along the line ■--■ in FIG. 2, and FIGS. 7 and V are configuration diagrams showing the second and third embodiments of the present invention, respectively. 4...Windshield, 5...Driver's side wiper, 6
... Passenger side wiper, 1... Wiper motor, 8...
・Negative pressure controller (actuator), 9...junction box, ? 0.11... Hydraulic pipeline, 12
．． 13... Blade, 22... Wiper arm, 23
... Arm head, 25 ... Driven side hydraulic cylinder,
21... Piston, 28... Bellows, 30...
Tension rod, 40... Drive shaft, 43° 44-.
・Cam, 46a, 46b, 47a, 47b
-...Protrusion, 50°51...Drive side hydraulic cylinder, 5
3... Piston, 54... Bellows, 56... Pressing rod, 60.100... Diaphragm housing, 61.101... Diaphragm, 62.102...
・Butsch rod, 70...Negative pressure control chamber, 14...Solenoid valve, 75...Electronic controller, 200
...Step motor (actuator). Applicant's agent Patent attorney Takehiko Suzue Figure 3 Figure 4

Claims (3)

[Claims] (1) A driven side hydraulic cylinder is rotatably mounted on the arm head which is reversely driven by the wiper motor, and a tension rod connected to the piston of this driven side hydraulic cylinder is pivotally supported on the wiper arm, and is synchronized with the wiper motor. A cam is attached to the rotating drive shaft, and a press rod connected to the piston of the drive side hydraulic cylinder is brought into contact with this cam, and the driven side hydraulic cylinder and the drive side hydraulic cylinder are connected through a hydraulic pipe filled with hydraulic oil. Then, as the motor rotates, the profile of the cam moves the pressure rod at the wiper reversal position to operate the piston of the driving side hydraulic cylinder, and the hydraulic pressure from the operation of this piston is transferred to the piston of the driven side hydraulic cylinder through the hydraulic conduit. A wiper arm load control device characterized in that the tension rod is moved by the piston and the arm load applied to the blade is reduced. (2) The cam is actuated in the axial direction by an actuator that responds to vehicle speed, and the amount of movement of the pressing rod is controlled by the profile of the cam to prevent the blade from floating at high speeds. The wiper arm load control device according to item (1). (3) Wiper arm load control according to claim (1), characterized in that the hydraulic pressure of the hydraulic pipe is controlled by an actuator that responds to the vehicle speed to prevent the blade from floating at high speeds. Device.