EP1233890A1

EP1233890A1 - Screen washer unit

Info

Publication number: EP1233890A1
Application number: EP01951437A
Authority: EP
Inventors: Wilfried Merkel; Roger Daenen
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2000-09-12
Filing date: 2001-06-28
Publication date: 2002-08-28
Also published as: DE10044896A1; WO2002022410A1

Abstract

The invention relates to a screen washer unit for a vehicle with at least one wiper arm (12), driven by a drive shaft (10), which may be displaced over a windscreen (14) and with a spraying device (16) with which cleaning fluid (22) from a reservoir (24) may be sprayed in front of a longitudinal side (26, 28) of the wiper blade onto the windscreen (14), by means of a spray nozzle (18, 20). The spray device (16) is controlled by means of a mechanical controller (30), such that the cleaning fluid (22) is only sprayed before the longitudinal edge (26, 28) of the wiper blade, when the above is in the direction of movement (32, 34) of the wiper blade. According to the invention, the drive shaft (10) indirectly or directly drives at least a part (36, 38) of the mechanical controller (30) and thus controls the issue of the cleaning agent (22).

Description

Wiper system

State of the art

The invention is based on a windshield wiper system according to the preamble of claim 1.

Known windshield wiper systems for vehicles have at least one wiper arm which is driven by a drive shaft and which can be moved with a wiper blade over a windshield of the vehicle. To the windshield in case of insufficient moisture to humidify and purify particular, ^■ windshield wiper systems often have a sprayer, can be sprayed with the cleaning agent through spray nozzles on the windshield. The cleaning agent can be water and / or chemical or biological agents, for example antifreeze, soapy water, etc.

The spray nozzles can be fastened to a component below and / or above the windshield, for example on a bonnet, a tailgate, etc. Furthermore, they can be designed to be rotatable with the wiper arm, for example as Spray bar on the wiper blade, as a spray nozzle on the drive shaft, etc.

In known spray devices, the case can occur that the cleaning agent is sprayed onto the windshield in front of the long side of the wiper blade facing away from the direction of movement and is only wiped away from the wiper blade after passing through a turning point. In the meantime, the cleaning agent obstructs the view. Furthermore, the cleaning agent can be cleaned together with the

Wiper blade can be used, partially blown by a wind of the vehicle over the windshield. There is an increased consumption of cleaning agents. A detergent storage container must either be large in size or detergent must be refilled frequently. Furthermore, the increased consumption of cleaning agents can lead to an increased environmental impact, in particular if the cleaning agent contains chemical agents.

To avoid this, DE 196 12 133 AI

Wiper blade proposed with a spray device, the mechanically controlled spray only on the windshield in front of the long side of the wiper blade pointing in the direction of movement. The wiper blade has a support bracket system with a main bracket, which is articulated to intermediate brackets. Claw brackets are articulated to the intermediate brackets, which can hold and guide a wiper strip with their retaining claws.

The wiper strip is made of an elastically deformable material and essentially consists of a back strip to which two wiper lips are integrally formed. The wiper lips are arranged parallel to one another in the longitudinal direction of the wiper blade. In the back bar there is also a longitudinal washing liquid channel with a flat Chen oval cross-section molded. The washer fluid channel is equipped with a series of dispensing openings that open on the opposite long sides of the back bar. If the wiper blade ^' with the wiper strip is moved over a windshield, the wiper strip deforms depending on the direction of movement. The dispensing openings, which point in the direction facing away from the direction of movement, are closed by the elastic deformation of the wiper strip, as a result of which only washing liquid is dispensed through the dispensing openings pointing in the direction of movement.

The wiper strip is a consumable item that is worn out by the wiping process and must be replaced from time to time. The described wiper strip is structurally far more complex than conventional wiper strips, which in the _. described execution increased costs arise. Furthermore, the wiper strip is exposed to very different weather conditions, which can change the material properties. The wear and the material properties that change over time can have a direct effect on the dispensing of the washing liquid and adversely affect the function of the spray device.

Furthermore, the spray device is not suitable for particularly high pressures, for example if the washing liquid is to be applied to the windshield at high pressure in order to achieve an additional cleaning effect. The discharge openings in the wiper strip, which point in the direction facing away from the direction of movement, can be opened by a high pressure of the washing liquid.

In addition, a windshield wiper system with an electronically controlled spraying device is known from GB 2 326 083 A. The windshield wiper system has two wiper arms, which are Shear motor are driven and can be moved with a wiper blade over a windshield.

The spraying device has a storage container, from which two cleaning agent channels are led to the wiper blades. The channels open into a first and a second spray nozzle on each wiper blade, the first spray nozzle being directed to a first long side of the wiper blade and the second spray nozzle being directed to a second long side of the wiper blade. A sensor is attached to the wiper motor, by means of which the direction of movement of the wiper arms is detected. In a first embodiment, the sensor is connected to a pump in the storage container via a signal line and, depending on the direction of movement of the wiper arms, controls the channel into which the pump should direct the cleaning agent. In a second embodiment, instead of one pump, two pumps are controlled via the signal line, and in a third embodiment, a switchable valve is controlled.

Advantages of the invention

The invention is based on a windshield wiper system for a vehicle with at least one wiper arm driven by a drive shaft, which can be moved with a wiper blade over a windshield. Furthermore, the windshield wiper system has a spray device with which cleaning agent can be sprayed from a storage container in front of a long side of the wiper blade onto the windshield via at least one spray nozzle, the spray device controlled by a mechanical control device only spraying the cleaning agent in front of the long side of the wiper blade when it enters the Direction of movement of the wiper blade points. It is proposed that the drive shaft drive at least part of the mechanical control device directly or indirectly and thereby control the discharge of the cleaning agent. Visibility from the cleaning agent is avoided and cleaning agent is saved. Furthermore, the drive shaft and, in particular, its rotary movement are advantageously used to drive a part of the mechanical control device and to control the outlet, as a result of which additional components can be saved, such as electronic sensors, signal lines, additional pumps, etc. It can be a particularly structurally simple, inexpensive and space-saving control device can be created with a long service life. Furthermore, the spray device can be operated at high pressure and can be designed independently of a wiper strip, which can be formed by an inexpensive standard component.

The mechanical control device can be formed by various devices which appear useful to the person skilled in the art. A particularly simple construction, which can be integrated in a space-saving manner in the area of the drive shaft, can, however, be achieved with a rotary slide valve driven by the drive shaft, the control course of which follows a hysteresis loop. Between two turning points of the wiper arm, the spray nozzle pointing in the direction of movement is always connected to the storage container via the rotary slide valve.

The rotary slide valve can be integrated between the drive shaft and various non-rotatable components, for example a body panel, etc. However, the rotary slide valve between the drive shaft is particularly advantageous and a non-rotatable connection part for the cleaning agent, where it can be hidden, integrated with little additional space and few additional components. The cleaning agent is advantageously passed through a channel introduced into the drive shaft. Additional components, such as hoses, can be saved and the assembly effort and costs can be reduced.

The channels can be introduced into the drive shaft by various methods, for example by drilling,

Eroding etc. A particularly cost-effective design can, however, be achieved if the channel is formed on at least part of the drive shaft during manufacture. An extrusion process with which one and in particular several channels can be introduced into the drive shaft at low cost is particularly advantageous. Aluminum or an aluminum alloy is preferably used as the material for the drive shaft.

In order to avoid that cleaning agent is sprayed over the windshield at turning points of the wiper arm and that cleaning agent cannot be wiped away, or cannot be wiped off immediately, it is proposed in an embodiment of the invention that in the area of at least one turning point of the wiper arm the spray nozzle is switched off, which points in the direction of movement in which the wiper arm moved in front of the turning point. This can be achieved in a structurally simple and inexpensive manner by means of a web arranged in the connecting part of the cleaning agent, which separates the spray nozzle in at least one turning point or interrupts a connection between the storage container and the spray nozzle. In a further embodiment of the invention it is proposed that at least one spray nozzle is directed in front of each longitudinal side of the wiper blade and that the spray nozzles can be controlled via the mechanical control device depending on the direction of movement of the wiper blade. During the entire wiping movement, cleaning agents can always be applied to the windshield in front of the long side pointing in the direction of movement.

The spray nozzles can have different shapes and can be attached to different positions of the wiper arm and the wiper blade, for example individual spray nozzles and / or spray strips can be fastened to the wiper blade and / or to the wiper arm, etc. In one embodiment, the spray nozzles are proposed in the region of the drive shaft of the To arrange wiper arms, particularly advantageously in a cap fastened to the drive shaft, which can simultaneously serve as a cover for the drive shaft. Additional components, such as in particular nozzle heads, lines from the drive shaft to the wiper arm and / or to the wiper blade, etc., can be saved and the assembly effort and costs can be reduced.

The solution according to the invention can be used in all windshield wiper systems which appear sensible to a person skilled in the art, such as, for example, in single arm wiper systems, counter-rotating wiper systems, synchronous wiper systems, etc. drawing

Further advantages result from the following description of the drawing. In the drawing, an embodiment of the invention is shown. The drawing, the description and the claims contain numerous features in combination. The person skilled in the art will expediently also consider the features individually and combine them into useful further combinations.

Show it:

1 shows a detail of a windshield wiper system, FIG. 2 shows a drive shaft of a windshield wiper system according to FIG. 1, FIG. 3 shows a longitudinal section through a connecting part for a cleaning agent with a rotary slide valve of a drive shaft according to FIG. 2,

Fig. 4 a connecting part from above,

Fig. 5 a control ring of a rotary slide valve from the side,

Fig. 6 a control ring according to FIG. 5 from below, F Fiigg. 7 7 a control ring according to FIG. 5 from the side,

Fig-. 8 a shaft connection part from the side,

Fig. 9 from below, Fig. 10 a shaft cap with two spray nozzles and 11-22 a section along the line XI-XI in Fig. 3 in different wiper arm positions.

Description of the embodiment

1 shows a section of a windshield wiper system for a motor vehicle, the wiper bearings of which are fastened to a body 58 of the motor vehicle via a circuit board 106. The circuit board 106 carries a wiper drive with a wiper motor 60, the motor shaft 62 of which drives cranks 66 via a crank 64 and a linkage (not shown in more detail), each of which is firmly connected to a drive shaft 10 for a windshield wiper. The drive shaft 10 is mounted radially and axially in a bearing housing 68 of the wiper bearing. The drive shaft 10 protrudes from the body 58 and moves a wiper arm 12 attached to its free end with a wiper blade (not shown in detail) over a windshield 14 (FIG. 11). The wiper arm 12 has a fastening part 70 which is connected in an articulated manner via a knee joint 72 to a joint part 74, to which a wiper rod 76 is rigidly connected. The wiper blade is suspended in the wiper rod 76 at a bow-shaped end 78. The fastening part 70 has at one end a bearing point 80, via which the fastening part 70 is connected in a rotationally fixed manner to the drive shaft 10 via a nut 82 screwed onto the drive shaft 10.

Furthermore, the windshield wiper system has a spray device 16 with two spray nozzles 18, 20, each of which is in front of a longitudinal Page 26, 28 of the wiper blade are directed and can be sprayed onto the windshield 14 via the cleaning agents 22 from a storage container 24 with a pump 84 in front of the longitudinal sides 26, 28 of the wiper blade (FIGS. 1, 2, 12 and 18). The spray nozzles 18, 20 are formed on a plastic cap 54 fastened on the drive shaft 10, which cap simultaneously serves as a cover for the drive shaft 10 and the nut 82 (FIGS. 1 and 2). The spray device 16 sprays the cleaning agent 22, controlled by a mechanical control device 30, only onto the longitudinal side 26, 28 of the wiper blade pointing in the direction of movement 32, 34 (FIGS. 11 to 22).

According to the invention, the mechanical control device 30 has a rotary slide valve 40 driven by the drive shaft 10. The rotary slide valve 40 is between a non-rotatable one

Connection part 42 arranged for the cleaning agent 22 and the drive shaft 10 and has a shaft connection part 36 made of rubber and non-rotatably connected to the drive shaft 10 and a plastic control ring 38 (FIGS. 3 to 9). One part of the shaft connection part 36 projects into the control ring 38 and is connected to it via controlling driver elements 88, 90, namely webs 90 arranged on the control ring 38 engage in two grooves 88 made in the shaft connection part 36 (FIGS. 5, 6, 7, 9 and 11 to 22). In the direction of the wiper arm 12, the rotary slide valve 40 is sealed with a sealing ring 86 between the shaft connecting part 36 and the connecting part 42 for the cleaning agent 22.

Two connecting channels 92, 94 are introduced in the control ring 38, via which the cleaning agent 22 from the connecting part 42 into the shaft connecting part 36 in two transverse channels 96, 98 and can be guided by the transverse channels 96, 98 into two axially aligned channels 100, 102 (FIGS. 3, 5, 6, 7 and 11 to 22). The channels 100, 102 are with two in the axial direction. aligned channels 44, 46 connected in a first part 56 of the drive shaft 10. The channels 44, 46 are formed during the production of the part 56 in an extrusion process, the part 56 being made of aluminum. On the first part 56 of the drive shaft 10, a second part 108 made of steel of the drive shaft 10 is fastened (FIG. 10). Two channels 110, 112 are introduced into the steel part 108, which connect the channels 44, 46 to a transverse channel 104 in the cap 54 and to the spray nozzles 18, 20.

If the windshield wiper system is actuated by the spray device 16, the wiper arm 12 with the wiper blade — shown schematically in FIG. 11 — moves from an initial position in the direction 32 on the windshield 14. In the initial position, which at the same time is a turning point 48 of the wiper arm 12 is the first ^'transverse channel 96 is located radially next to the conjunction channel 92 and second transverse channel 98 is closed by a molded-in connector 42 web 52nd In the starting position, no cleaning agent 22 is sprayed onto the windshield 14.

If the wiper arm 12 moves in the direction 32, the shaft connecting part 36 fastened to the drive shaft 10 rotates relative to the control ring 38 and the transverse channel 96 comes to rest over the connecting channel 92 (FIGS. 12 and 13). Cleaning agent 22 is sprayed in front of the longitudinal side 26 of the wiper blade via the spray nozzle 20. In the wiper arm position in FIG. 13, the connecting channel 92 and the transverse channel 96 lie directly one above the other. Furthermore, the webs 90 of the control ring 38 come to rest on the side walls of the grooves 88. From the wiper arm position in FIG. 13, the shaft connection part 36 and the control ring 38 are positively connected via the driver elements 88, 90 and the shaft connection part 36 and the control ring 38 are rotated together by the drive shaft 10 in the direction 32 to a turning point 50 of the wiper arm 12 (FIG 14, 15 and 16). Shortly before the turning point 50 of the wiper arm 12, the spray nozzle 20 is switched off by the web 52 in the connecting part 42 closing the transverse channel 96.

After the turning point 50, the wiper arm moves in the direction 34. The shaft connection part 36 rotates relative to the control ring 38 and the transverse channel 98 comes to rest over the connecting channel 94 (FIGS. 17, 18 and 19). Via the spray nozzle 18 ^• Cleaning means 22 is sprayed the wiper blade before the long side 28th In the wiper arm position in FIG. 19, the connecting duct 94 and the transverse duct 98 lie directly one above the other. Furthermore, the webs 90 of the control ring 38 come to rest on the side walls of the grooves 88. From the wiper arm position in FIG. 19, the shaft connection part 36 and the control ring 38 are positively connected via the driver elements 88, 90 and the shaft connection part 36 and the control ring 38 are rotated together by the drive shaft 10 in the direction 34 to the turning parts 48 of the wiper arm 12 (Figures 20, 21 and 22). Shortly before the turning point 48 of the wiper arm 12, the spray nozzle 18 is switched off by the web 52 in the connecting part 42 closing the transverse channel 98. The control curve of the rotary slide valve 40 follows a hysteresis loop, ie between the turning points 48, 50 of the wiper arm 12, the rotary slide valve 40 is always the one in the direction of movement 32, 34 pointing spray nozzle 18, 20 connected to the reservoir 24.

reference numeral

10 drive shaft 58 body

12 wiper arm 60 wiper motor

14 windshield 62 motor shaft

16 spray device 64 crank

18 spray nozzle 66 crank

20 spray nozzle 68 bearing housing

22 cleaning agent 70 fastening part

24 storage containers 72 knee joint

26 Long side 74 joint part

28 Long side 76 Wiper rod

30 control device 78 end

32 Direction of movement 80 Bearing point

34 ^{Direction of} movement ^■ 82 mother

36 shaft connection part 84 pump

38 control ring 86 sealing ring

40 rotary slide valve 88 driver elements

42 connecting part 90 driver elements

44 channel 92 connecting channel

46 channel 94 connecting channel

48 Turning point 96 cross channel

50 turning point 98 cross channel

52 bridge 100 channel

54 cap 102 channel

56 part 104 cross channel 106 circuit board

108 part

110 channel

112 channel

Claims

Expectations

1. Windscreen wiper system for a vehicle with at least one wiper arm (12) driven by a drive shaft (10), which can be moved with a wiper blade over a windshield (14), and with a spray device (16) with which at least one spray nozzle (18 , 20) cleaning agent (22) can be sprayed from a storage container (24) in front of a longitudinal side (26, 28) of the wiper blade onto the windshield (14), the spray device (16) the cleaning agent (22) via a mechanical control device (30) controlled only in front of the longitudinal side (26, 28) of the wiper blade when it points in the direction of movement (32, 34) of the wiper blade, characterized in that the drive shaft (10) at least a part (36, 38) of the mechanical control device (30 ) drives directly or indirectly and thereby controls the discharge of the cleaning agent (22).

2. Windshield wiper system according to claim 1, characterized in that the mechanical control device (30) has at least one rotary slide valve (40) driven by the drive shaft (10), the control course of which follows a hysteresis loop.

3. Windshield wiper system according to claim 2, characterized in that the rotary slide valve (40) is arranged between a rotationally fixed connecting part (42) for the cleaning agent (22) and the drive shaft (10).

4. Windscreen wiper system according to one of the preceding claims, characterized in that in the drive shaft (10) at least one with the spray nozzle (18, 20) connected channel (44, 46) is introduced.

5. Windshield wiper system according to claim 4, characterized in that the channel (44, 46) is formed on at least a part (56) of the drive shaft (10) during manufacture.

6. Windscreen wiper system according to one of the preceding claims, characterized in that in the region of at least one turning point (48, 50) of the wiper arm (12) the spray nozzle (18, 20) is switched off, which points in the direction of movement (32, 34) in which the wiper arm (12) moved in front of the turning point (48, 50).

7. Windscreen wiper system according to claim 3 and 6, characterized in that in the connecting part (42) a spray nozzles (18, 20) switching off web (52) is arranged.

8. Windscreen wiper system according to one of the preceding claims, characterized in that at least one spray nozzle (18, 20) is directed in front of each longitudinal side (26, 28) of the wiper blade and the spray nozzles (18, 20) via the mechanical control device (30) depending on the direction of movement (32, 34) of the wiper blade can be controlled.

9. Windscreen wiper system according to one of the preceding claims, characterized in that the spray nozzles (18, 20) are arranged in the region of the drive shaft (10) of the wiper arm (12).

10. Windscreen wiper system according to claim 9, characterized in that the spray nozzles (18, 20) in a on the drive shaft (10) attached cap (54) are introduced.