WO2008029990A1

WO2008029990A1 - Wiper arm assembly

Info

Publication number: WO2008029990A1
Application number: PCT/KR2007/003532
Authority: WO
Inventors: Wi-Yeong Park
Original assignee: Dongyang Mechatronics Corp.
Priority date: 2006-09-06
Filing date: 2007-07-23
Publication date: 2008-03-13
Also published as: KR100767444B1; CN101506010B; CN101506010A

Abstract

The wiper arm assembly includes: a blade wiping a glass; a retainer connected to the blade and pressing the blade against the glass; an arm head connected to the retainer; a central hole formed in a center of the blade; a support shaft disposed in the central hole to be perpendicular to a lengthwise direction of the blade; a combination hole which is formed in the retainer and through which the support shaft is rotatably accommodated; and a vibration-preventing unit preventing the blade from freely moving in a widthwise direction of the blade relative to the retainer due to a frictional force between the blade and the glass of the vehicle while the blade rotates forwards and backwards together with the retainer or a rotation-restricting unit restricting rotation of the blade while the blade rotates around the support shaft relative to the retainer by an external force.

Description

WIPER ARM ASSEMBLY

Technical Field

[1] The present invention relates to a rear wiper arm assembly of a vehicle, and more particularly, to a wiper arm assembly having an improved structure in which, while a blade rotates forwards and backwards so as to remove foreign substances stuck on a glass of the vehicle, the blade is prevented from freely moving in its widthwise direction relative to a retainer due to a frictional force between the blade and the glass of the vehicle. Background Art

[2] Conventionally, a rear wiper needs to be installed on a rear glass of a vehicle according to an inclination angle of the rear glass of a vehicle. In most cases, a rear wiper is not installed on a rear glass of a so-called sedan notch back type vehicle. However, a rear wiper is necessarily installed on a rear glass of a hatch back type vehicle, such as a sports utility vehicle (SUV). The installation of the rear wiper on the rear glass of a vehicle is done because a negative pressure is generated on the rear glass while driving and dust easily collects on the rear glass according to the type of vehicle.

[3] A general construction of such a rear wiper is illustrated in FIG. 1. Conventionally, the rear wiper of a rear glass is an assembly comprised of a plurality of components and hence, hereinafter referred to as a wiper arm assembly 1.

[4] Referring to FIG. 1, the wiper arm assembly 1 includes three elements. In detail, the wiper arm assembly 1 includes an arm head 2, a retainer 3, and a blade 4. The arm head 2 is fixed on a pivot shaft that is installed on a body and is rotated together with the pivot shaft due to rotations of the pivot shaft. The retainer 3 is combined with one end of the arm head 2 and transmits a rotation force of the arm head 2 to the blade 4. The blade 4 slides in contact with a glass of the vehicle and wipes and removes foreign substances stuck on the glass of the vehicle.

[5] In the wiper arm assembly 1 having the above structure, a tension spring (not shown) is usually installed in the structure for connecting the retainer 3 and the arm head 2 so that the blade 4 can apply pressure to the glass of the vehicle. One end of the tension spring is attached to the retainer 3 and the other end thereof is attached to the arm head 2.

[6] In the wiper arm assembly 1 having the above structure, the blade 4 and the retainer

3 are combined with each other to be separated from each other. This is because, in order to replace or repair the blade 4 which is an expendable, only the blade 4 is separated from the retainer 3 in a simple manner and is replaced or repaired without the need for disassembling the wiper arm assembly 1. [7] However, there is a problem in that, while the blade rotates forwards and backwards while contacting the glass of the vehicle so as to remove foreign substances stuck on the glass of the vehicle, the blade 4 moves in a rotation direction of the retainer 3, that is, in a width wise direction W of the blade 4 illustrated in FIG. 2, due to a frictional force between the blade 4 and the glass of the vehicle. When such a movement occurs in the state where the wiper arm assembly 1 is installed in the vehicle, noise increases and the movement may adversely affect user's susceptible quality. In addition, durability of the wiper arm assembly 1 is lowered.

[8] The blade 4 is combined with the retainer 3 to be separated therefrom. To this separation, the blade 4 is combined with the retainer 3 so that the blade 4 can rotate at an angle around a support axis. However, when the blade 4 rotates excessively relative to the retainer 3 due to an unintended external force, the blade 4 or the glass of the vehicle may be damaged. Disclosure of Invention Technical Problem

[9] However, there is a problem in that, while the blade rotates forwards and backwards while contacting the glass of the vehicle so as to remove foreign substances stuck on the glass of the vehicle, the blade 4 moves in a rotation direction of the retainer 3, that is, in a width wise direction W of the blade 4 illustrated in FIG. 2, due to a frictional force between the blade 4 and the glass of the vehicle. When such a movement occurs in the state where the wiper arm assembly 1 is installed in the vehicle, noise increases and the movement may adversely affect user's susceptible quality. In addition, durability of the wiper arm assembly 1 is lowered.

[10] The blade 4 is combined with the retainer 3 to be separated therefrom. To this separation, the blade 4 is combined with the retainer 3 so that the blade 4 can rotate at an angle around a support axis. However, when the blade 4 rotates excessively relative to the retainer 3 due to an unintended external force, the blade 4 or the glass of the vehicle may be damaged. Advantageous Effects

[11] As described above, in the wiper arm assembly 10 according to the present invention, the blade 40 is prevented from freely moving in the widthwise direction W illustrated in FIG. 2 while the blade 40 wipes the glass of the vehicle by interaction between the protrusion jaw 35 and the support wall surface 44.

[12] In addition, the suspending jaw 46 and the protrusion jaw 35 interact with each other and the blade 40 is prevented from being spaced apart from the glass of the vehicle by an unintended external force and from being damaged.

[13] In addition, the blade 40 can be easily separated from the retainer 30 so as to replace or repair the blade 40 by an interaction between the circular arc portion 421 and the linear portion 423 disposed on the support shaft 42 and an interaction between the accommodation portion 38 and the opened portion 39 disposed in the retainer 30. Description of Drawings

[14] The above and other features and advantages of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which:

[15] FIG. 1 is a schematic view of a vehicle in which a conventional wiper arm assembly is installed;

[16] FIG. 2 illustrates the state where a blade moves freely while the wiper arm assembly illustrated in FIG. 1 operates;

[17] FIG. 3 is a schematic cross-sectional view of a wiper arm assembly according to an embodiment of the present invention;

[18] FIG. 4 is an enlarged view of portion 'A' illustrated in FIG. 3;

[19] FIG. 5 is a view in which the portion illustrated in FIG. 4 is seen in a 'Z' direction and illustrates the state where a rubber part of the blade is removed;

[20] FIG. 6 is a cross-sectional view taken along line VI-VI of FIG. 3;

[21] FIG. 7 is a perspective view illustrating a guide portion of the wiper arm assembly illustrated in FIG. 3;

[22] FIG. 8 illustrates the state where a protrusion jaw is supported on a support wall surface in the wiper arm assembly illustrated in FIG. 3;

[23] FIG. 9 illustrates the state where the protrusion jaw is suspended on a suspending jaw in the wiper arm assembly illustrated in FIG. 3; and

[24] FIG. 10 illustrates the state where the blade is separated from the wiper arm assembly illustrated in FIG. 3. Best Mode

[25] The present invention will now be described more fully with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown.

[26] FIG. 3 is a schematic cross-sectional view of a wiper arm assembly according to an embodiment of the present invention, FIG. 4 is an enlarged view of portion 'A' illustrated in FIG. 3, FIG. 5 is a view in which the portion illustrated in FIG. 4 is seen in a 'Z' direction and illustrates the state where a rubber part of the blade is removed, FIG. 6 is a cross-sectional view taken along line VI-VI of FIG. 3, FIG. 7 is a perspective view illustrating a guide portion of the wiper arm assembly illustrated in FIG. 3, and FIG. 8 illustrates the state where a protrusion jaw is supported on a support wall surface in the wiper arm assembly illustrated in FIG. 3.

[27] Referring to FIGS. 3 through 8, the wiper arm assembly 10 includes an arm head 20, a retainer 30, and a blade 40.

[28] One end of the arm head 20 is fixed on a pivot shaft 11 that is fixed on a vehicle using a cap nut 12, for example. The pivot shaft 11 is connected to a link structure (not shown) connected to a motor and is rotated by a driving force of the motor. The arm head 20 rotates around a portion of the pivot shaft 11 at a predetermined angle as the pivot shaft 11 is rotated.

[29] One end of the retainer 30 is combined with the arm head 20 so that the retainer 30 can rotate around the arm head 20. The other end of the retainer 30 is combined with the blade 40 for wiping the glass of the vehicle. The retainer 30 rotates forwards and backwards around the pivot shaft 11 together with the blade 40 by a driving force of a driving motor that is connected to the pivot shaft 11, the driving force being transmitted through the arm head 20. In addition, the retainer 30 is connected to the arm head 20 by a tension spring 50 for pressing the blade 40 against the glass of the vehicle. That is, one end of the tension spring 50 is suspended on the retainer 30 and the other end thereof is suspended on the arm head 20.

[30] The retainer 30 includes a combination hole 37 and a guide portion 32, for connection with the blade 40 which will be described later in greater detail.

[31] The combination hole 37 is formed in the other end of the retainer 30, that is, in a portion connected to the blade 40. The combination hole 37 includes an accommodation portion 38 and an opened portion 39. The accommodation portion 38 accommodates a support shaft 42 of the blade 40 which will be described later. The opened portion 39 connects the accommodation portion 38 and the outside, and a width of the opened portion 39 is smaller than a diameter of the accommodation portion 38.

[32] The guide portion 32 includes an elastic portion 34 and a protrusion jaw 35. The elastic portion 34 protrudes from a body of the retainer 30 in a direction that crosses a lengthwise direction of the retainer 30. Cross-sections of the elastic portion 34 perpendicular to its protrusion direction are rectangular. A pair of protrusion jaws 35 is provided. The pair of protrusion jaws 35 protrudes from the elastic portion 34 in opposite directions. The pair of protrusion jaws 35 is disposed in such a way that it is not placed in a straight line. The protrusion direction of the elastic portion 34 and the protrusion direction of the pair of protrusion jaws 35 are approximately perpendicular to each other. The elastic portion 34 can be torsionally deformed around the protrusion direction of the elastic portion 34.

[33] The blade 40 is combined with the other end of the retainer 30 and is installed to rotate with the retainer 30. A central hole 41 is formed in the center of the blade 40. The support shaft 42 is disposed in the central hole 41 in a direction perpendicular to the lengthwise direction of the blade 40. The support shaft 42 is connected to both sidewalls of the central hole 41. Cross-sections of the support shaft 42 perpendicular to its lengthwise direction include a circular arc portion 421 which is a portion of a circle, and a pair of linear portions 423 that are parallel to a diameter of the circle and face each other. The circular arc portion 421 is almost the same as or is slightly smaller than an inner diameter of the accommodation portion 38 but is larger than a distance between both sidewalls of the opened portion 39. Thus, the circular arc portion 421 does not pass the opened portion 39. However, since a distance between the linear portions 423 is smaller than the distance between the both sidewalls of the opened portion 39, when the linear portions 423 are parallel to the both sidewalls of the opened portion 39, the linear portions 423 can be separated from the combination hole 37 through a path between the both sidewalls of the opened portion 39. For this reason, the support shaft 42 may be separated from the combination hole 37 disposed in the retainer 30 while the support shaft 42 rotates in slide with an inner circumference of the combination hole 37. In this way, a position in which the support shaft 42 cannot be separated from the combination hole 37 is referred to as a first position, and a position in which the support shaft 42 can be separated from the combination hole 37 is referred to as a second position.

[34] A portion of the central hole 41 extends so that a pair of support wall surfaces 44 is formed. The support wall surfaces 44 are spaced apart from each other by a predetermined gap to face each other. The support wall surfaces 44 are maintained in contact with the pair of protrusion jaws 35. The pair of support wall surfaces 44 and the pair of protrusion jaws 35 disposed in the retainer 30 interact with each other and constitute a vibration-preventing unit for preventing the blade 40 from freely moving in a widthwise direction of the blade 40 relative to the retainer 30 due to a frictional force between the blade 40 and the glass of the vehicle while the blade 40 rotates forwards and backwards together with the retainer 30.

[35] A suspending jaw 46 is formed in an upper portion of each support wall surface 44.

The suspending jaw 46 protrudes from the support wall surface 44 to a lengthwise direction of the support shaft 42. Consequently, a pair of suspending jaws 46 is disposed to face each other.

[36] An operation of the wiper arm assembly 10 having the above structure according to the present invention will now be described in detail.

[37] First, an operation of the vibration-preventing unit which is one objective of the present invention, will be described.

[38] In the state where the wiper arm assembly 10 is installed in the vehicle, the blade 40 is pressed again the glass of the vehicle by the retainer 30 and the tension spring 50. In this state, when it rains while a driver drives the vehicle or when the driver wants to remove foreign substances stuck on the glass of the vehicle, a wiper switch disposed in a driver's seat is operated. Then, electricity is applied to a motor for driving a wiper disposed on a body, and when the motor rotates, the pivot shaft 11 rotates. Thus, a rotation force of the motor is transmitted to the arm head 20 fixed on the pivot shaft 11 and the rotation force allows the blade 40 to rotate by the retainer 30. A frictional force is generated when the blade 40 contacts the glass of the vehicle, and the blade 40 wipes the glass of the vehicle. In this procedure, a torsion force is applied to the blade 40 in the state where the support shaft 42 and the combination hole 37 are combined with each other. Thus, the blade 40 instantaneously freely moves in its width wise direction illustrated in FIG. 2, around the support shaft 43. However, since the protrusion jaw 35 and the support wall surface 44 are maintained in contact with each other, as illustrated in FIGS. 6 and 8, the torsion force of the blade 40 is transmitted to the retainer 30 through the support wall surface 44 and the protrusion jaw 35. Thus, the torsion force is applied to both the blade 40 and the retainer 30 so that the blade 40 is prevented from freely moving in the widthwise direction W illustrated in FIG. 2.

[39] An operation of a rotation-restricting unit which is another objective of the present invention, will now be described.

[40] The blade 40 may rotate around the support shaft 42 relative to the retainer 30 due to an unintended external force. The blade needs to be separated from the retainer 30 so as to replace or repair the blade 40. However, if such a demand is no need, for example, when a vehicle is placed in an automatic car washing machine, if a rotation brush of the automatic car washing machine is suspended on the blade 40, the blade 40 may rotate relative to the retainer 30 in unintended circumstances. In this procedure, if the blade 40 rotates excessively around the support shaft 42, the blade 40 may be damaged. However, like in the present embodiment, if, while the blade 40 rotates around the support shaft 42, the protrusion jaw 35 and the support wall surface 44 are maintained in contact with each other, the blade 40 slides and rotates at a predetermined angle, as illustrated in FIGS. 6 and 8, the protrusion jaw 35 is suspended on the protrusion jaw 46. Thus, excessive rotation of the blade 40 is prevented, and if an external force is removed, the blade 40 is restored to the state where the blade 40 contacts the glass of the vehicle. As a result, the blade 40 is prevented from rotating so that the blade 40 can be separated from the glass of the vehicle due to an unintended external force and from being damaged.

[41] In addition, when the blade 40 is separated from the retainer 30 so as to replace or repair the blade 40, the support shaft 42 should rotate to be placed in the above- mentioned second position. However, the second position can be reached only when the protrusion jaw 35 suspended on the suspending jaw 46 must pass a path between the pair of protrusion jaws 35. Thus, an operation of releasing suspension of the protrusion jaw 35 suspended on the suspending jaw 46 will now be described. [42] A pair of suspending jaws 46 is disposed, and a distance between the suspending jaws 46 is larger than the thickness of the elastic portion 34 disposed on the retainer 30 and is smaller than a distance between both ends of the pair of protrusion jaws 35. However, since the pair of protrusion jaws 35 is not placed in a straight line, a user applies an external force to the pair of protrusion jaws 35 so that any one of the pair of protrusion jaws 35 illustrated in FIG. 7 passes a path between the suspending jaws 46 and then the other protrusion jaw 35 passes the path between the protrusion jaws 46. In this case, since the elastic portion 34 can be torsionally deformed, the protrusion jaws 35 can pass the path between the suspending jaws 46 as described above. When the support shaft 42 reaches the second position through the above procedure, the linear portion 423 of the support shaft 42 corresponds to both sidewalls of the opened portion 39, as illustrated in FIG. 10 so that the support shaft 42 is separated from the combination hole 37 and the blade 40 and the retainer 30 can be separated from each other.

[43] As described above, in the wiper arm assembly 10 according to the present invention, the blade 40 is prevented from freely moving in the widthwise direction W illustrated in FIG. 2 while the blade 40 wipes the glass of the vehicle by interaction between the protrusion jaw 35 and the support wall surface 44.

[44] In addition, the suspending jaw 46 and the protrusion jaw 35 interact with each other and the blade 40 is prevented from being spaced apart from the glass of the vehicle by an unintended external force and from being damaged.

[45] In addition, the blade 40 can be easily separated from the retainer 30 so as to replace or repair the blade 40 by an interaction between the circular arc portion 421 and the linear portion 423 disposed on the support shaft 42 and an interaction between the accommodation portion 38 and the opened portion 39 disposed in the retainer 30.

[46] In the present embodiment, the guide portion 32 includes an elastic portion 34 of which cross-sections perpendicular to its protrusion direction are rectangular and which can be elastically deformed, and a pair of protrusion jaws 35 protruding from the elastic portion 34 in opposite directions. However, the guide portion 32 may be also constituted with a different shape from that of the protrusion jaw 35.

[47] In the present embodiment, cross-sections of the support shaft 42 perpendicular to its lengthwise direction include a circular arc portion 421 which is a portion of a circle, and a pair of linear portions 423 that are parallel to a diameter of the circle and face each other. However, the cross-sections of the support shaft 42 perpendicular to its lengthwise direction may have various shapes having a difference in the thicknesses of the cross-sections of the support shaft 42 perpendicular to its lengthwise direction.

[48] While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by one of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims. Mode for Invention

[49] According to an aspect of the present invention, there is provided a wiper arm

[50] assembly, the wiper arm assembly including: a blade wiping a glass of a vehicle; a retainer connected to the blade and pressing the blade against the glass of the vehicle; an arm head connected to the retainer and rotating forwards and backwards the retainer and the blade by a rotation force transmitted from a body; a central hole formed in a center of the blade; a support shaft disposed in the central hole to be perpendicular to a lengthwise direction of the blade; a combination hole which is formed in the retainer and through which the support shaft is rotatably accommodated; and a vibration- preventing unit preventing the blade from freely moving in a widthwise direction of the blade relative to the retainer due to a frictional force between the blade and the glass of the vehicle while the blade rotates forwards and backwards together with the retainer, wherein the vibration-preventing unit includes: a pair of support wall surfaces extending from wall surfaces of the central hole of the blade and disposed to face each other; and a guide portion formed as a unitary body with the retainer and protruded toward the blade, and wherein a portion of the guide portion is maintained in contact with the support wall surfaces while the blade rotates relative to the retainer. [51] According to another aspect of the present invention, there is provided a wiper

[52] arm assembly, the wiper arm assembly including: a blade wiping a glass of a vehicle;

[53] a retainer connected to the blade and pressing the blade against the glass of the vehicle; an arm head connected to the retainer and rotating forwards and backwards the retainer and the blade by a rotation force transmitted from a body; a central hole formed in a center of the blade; a support shaft disposed in the central hole to be perpendicular to a lengthwise direction of the blade; a combination hole which is formed in the retainer and through which the support shaft is rotatably accommodated; and a rotation-restricting unit restricting rotation of the blade while the blade rotates around the support shaft relative to the retainer by an external force, wherein the rotation-restricting unit includes: a pair of support wall surfaces extending from wall surfaces of the central hole of the blade and disposed to face each other; a pair of suspending jaws protruding from the pair of support wall surfaces in a lengthwise direction of the support shaft and facing each other; an elastic portion formed as a unitary body with the retainer and protruded toward the blade; and a pair of protrusion jaws protruding from the elastic portion in opposite direction.

[54] The guide portion may include: an elastic portion of which cross-sections perpendicular to its protrusion direction are rectangular and which can be elastically deformed; and a pair of protrusion jaws protruding from the elastic portion in opposite directions .

[55] The blade may include a pair of suspending jaws protruding from a pair of

[56] support wall surfaces in a lengthwise direction of the support shaft and facing each other, and the protrusion jaws may not be placed in a straight line, may be suspended on the suspending jaws and may restrict rotation of the blade while the blade rotates around the support shaft relative to the retainer, and can pass the suspending jaws by elastic torsion deformation of the elastic portion.

[57] Cross-sections of the support shaft perpendicular to its lengthwise direction may include a circular arc portion which is a portion of a circle, and a pair of linear portions that are parallel to a diameter of the circle and face each other, and

[58] the accommodation hole may include an opened portion having a width that is larger than a distance between the linear portions and is smaller than a diameter of the circle. Industrial Applicability

[59] The present invention provides a wiper arm assembly having an improved structure in which durability of the wiper arm assembly is improved and generation of noise is suppressed in the state where the wiper arm assembly is installed in the vehicle.

Claims

[1] A wiper arm assembly comprising: a blade wiping a glass of a vehicle; a retainer connected to the blade and pressing the blade against the glass of the vehicle; an arm head connected to the retainer and rotating forwards and backwards the retainer and the blade by a rotation force transmitted from a body; a central hole formed in a center of the blade; a support shaft disposed in the central hole to be perpendicular to a lengthwise direction of the blade; a combination hole which is formed in the retainer and through which the support shaft is rotatably accommodated; and a vibration-preventing unit preventing the blade from freely moving in a widthwise direction of the blade relative to the retainer due to a frictional force between the blade and the glass of the vehicle while the blade rotates forwards and backwards together with the retainer, wherein the vibration-preventing unit comprises: a pair of support wall surfaces extending from wall surfaces of the central hole of the blade and disposed to face each other; and a guide portion formed as a unitary body with the retainer and protruded toward the blade, and wherein a portion of the guide portion is maintained in contact with the support wall surfaces while the blade rotates relative to the retainer.

[2] The wiper arm assembly of claim 1, wherein the guide portion comprises: an elastic portion of which cross-sections perpendicular to its protrusion direction are rectangular and which can be elastically deformed; and a pair of protrusion jaws protruding from the elastic portion in opposite directions.

[3] The wiper arm assembly of claim 2, wherein the blade comprises a pair of suspending jaws protruding from a pair of support wall surfaces in a lengthwise direction of the support shaft and facing each other, and wherein the protrusion jaws are not placed in a straight line, are suspended on the suspending jaws and restrict rotation of the blade while the blade rotates around the support shaft relative to the retainer, and can pass the suspending jaws by elastic torsion deformation of the elastic portion.

[4] The wiper arm assembly of claim 1, wherein cross-sections of the support shaft perpendicular to its lengthwise direction include a circular arc portion which is a portion of a circle, and a pair of linear portions that are parallel to a diameter of the circle and face each other, and wherein the accommodation hole comprises an opened portion having a width that is larger than a distance between the linear portions and is smaller than a diameter of the circle. [5] A wiper arm assembly comprising: a blade wiping a glass of a vehicle; a retainer connected to the blade and pressing the blade against the glass of the vehicle; an arm head connected to the retainer and rotating forwards and backwards the retainer and the blade by a rotation force transmitted from a body; a central hole formed in a center of the blade; a support shaft disposed in the central hole to be perpendicular to a lengthwise direction of the blade; a combination hole which is formed in the retainer and through which the support shaft is rotatably accommodated; and a rotation-restricting unit restricting rotation of the blade while the blade rotates around the support shaft relative to the retainer by an external force, wherein the rotation-restricting unit comprises: a pair of support wall surfaces extending from wall surfaces of the central hole of the blade and disposed to face each other; a pair of suspending jaws protruding from the pair of support wall surfaces in a lengthwise direction of the support shaft and facing each other; an elastic portion formed as a unitary body with the retainer and protruded toward the blade; and a pair of protrusion jaws protruding from the elastic portion in opposite direction. [6] The wiper arm assembly of claim 5, wherein the protrusion jaws are not placed in a straight line and can pass the suspending jaws by elastic torsion deformation of the elastic portion.