Wiper device

Abstract

To further lower the height from a wiping surface and further suppress the generation of wind noise.SOLUTION: An arm head 50 includes a head-side hook portion 57 to which a tension spring 70 is hooked. An arm shank 40 comprises: a pair of sidewall portions 41 arranged to face each other in a wiping direction; a top wall portion 42 provided on an opposite side to the wiping surface side of the pair of sidewall portions 41 and connects the pair of sidewall portions 41; a shank-side hook portion 46 provided between the pair of sidewall portions 41 and to which the tension spring 70 is hooked; and a spring accommodating recess 47 provided at the top wall portion 42 and can accommodate a part of the tension spring 70. When the arm shank 40 is raised, a part of the tension spring 70 is accommodated in the spring accommodating recess 47, and when the arm shank 40 is raised and viewed from a direction in which the sidewall portions 41 face each other, the tension spring 70 is hidden by the sidewall portions 41.SELECTED DRAWING: Figure 10

Description

Technical Field

[0001] The present invention relates to a wiper device having a wiper blade for wiping a wiping surface and being swung by a swing shaft.

Background Art

[0002] Patent Document 1 describes a wiper arm including an arm head body fixed to a drive shaft, a retainer rotatably connected to the arm head body, and a return spring disposed between the arm head body and the retainer. The spring force of the return spring acts to press the wiper blade held by the retainer against the wiping surface.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, the wiper device is subjected to traveling wind when the vehicle is running. As a result, the wiper device generates a wind noise, especially when the vehicle is running at high speed. In recent electric vehicles and the like, since the power source is an electric motor, the noise is small, and the wind noise transmitted into the vehicle becomes annoying to the passengers. In order to suppress the generation of such wind noise, it is desirable to make the height from the wiping surface of the wiper device as low as possible and make it difficult to receive the traveling wind.

[0005] In the technique described in Patent Document 1, in a state where the retainer is tilted with respect to the arm head body, the return spring protrudes from the retainer toward the wiping surface side, and there is a relatively large dead space between the return spring and the retainer on the side opposite to the wiping surface side. Therefore, with the structure described in Patent Document 1, it has been difficult to sufficiently suppress the generation of wind noise.

[0006] An object of the present invention is to provide a wiper device capable of reducing the height from the wiping surface and further suppressing the generation of wind noise.

Means for Solving the Problems

[0007] In one aspect of the wiper device, an arm head fixed to a swing shaft, an arm shank having a proximal end rotatably attached to the arm head, a wiper blade attached to a distal end side of the arm shank, and provided between the arm head and the arm shank, A wiper device having a spring that presses the wiper blade against a wiping surface, wherein the arm head includes a first hook portion on which a proximal end side of the spring is hooked, and the arm shank includes a pair of side wall portions that are opposed to each other in a wiping direction of the wiper blade. And a top wall portion provided on the opposite side of the pair of side wall portions from the wiping surface side, connecting the pair of side wall portions, and provided between the pair of side wall portions, a second hook portion on which a distal end side of the spring is hooked, and provided on the top wall portion, a spring accommodating recess capable of accommodating at least a part of the spring, and when the arm shank is raised with respect to the arm head, at least a part of the spring is accommodated in the spring accommodating recess, and when the arm shank is raised with respect to the arm head and the arm shank is viewed from a direction in which the pair of side wall portions face each other, the spring is hidden by the pair of side wall portions.

Effects of the Invention

[0008] According to the present invention, it is possible to realize a wiper device in which the spring does not protrude greatly toward the wiping surface, the height from the wiping surface can be made lower, and thus the generation of wind noise can be further suppressed.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Mode for Carrying Out the Invention

[0010] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

[0011] FIG. 1 is a view of the wiper device seen from the front side, FIG. 2 is a view of the wiper device seen from the side, FIG. 3 is a view of the wiper device seen from the back side, FIG. 4 is a cross-sectional view taken along the line A-A of FIG. 1, FIG. 5 is a perspective view showing the arm shank and the wiper blade, FIG. 6 is a perspective view showing the inside of the arm shank, FIG. 7 is a perspective view of the arm head seen from the front side, FIG. 8 is a perspective view of the arm head seen from the back side, FIG. 9 is a perspective view showing the tension spring alone, FIG. 10 is a cross-sectional view showing the locked-back state of the wiper device, and FIG. 11 is a cross-sectional view taken along the line B-B of FIG. 10, respectively.

[0012] [Overview of Wiper Device] The wiper device 10 shown in FIGS. 1 to 4 wipes a windshield (wiping surface WS) provided on a back door of a vehicle such as an automobile. The wiper device 10 includes a wiper blade 20 that wipes the wiping surface WS, and a wiper arm 30 to which the wiper blade 20 is attached.

[0013] The proximal end side (the right side in FIGS. 1 to 4) of the wiper arm 30 is fixed to the distal end side of a swing shaft SH (see FIG. 4) of a rear wiper motor housed inside the back door by a fastening nut NT (see FIG. 4). Thereby, when the rear wiper motor is driven, the swing shaft SH swings, and as a result, the wiper arm 30 and the wiper blade 20 swing on the wiping surface WS.

[0014] The wiper blade 20 is attached to the distal end side (the left side in FIGS. 1 to 4) of the wiper arm 30. The wiper blade 20 includes a connecting member 21 that is rotatably attached to the distal end side of the wiper arm 30, and a blade rubber 22 that is held by the connecting member 21.

[0015] Here, the blade rubber 22 is formed in a long shape by extrusion molding of natural rubber or the like, and is held by the connecting member 21 via a pair of leaf springs (not shown) also called antivibrators. Covers 23 that cover the back sides of the pair of leaf springs and the blade rubber 22 are respectively provided on both longitudinal sides of the connecting member 21. Further, end caps 24 are respectively attached to both longitudinal sides of the pair of leaf springs and the blade rubber 22. Thereby, the blade rubber 22 is prevented from falling off from the pair of leaf springs.

[0016] The blade rubber 22 is pressed against the wiping surface WS by the spring force of a tension spring 70 (see FIG. 4) provided inside the wiper arm 30. Then, the wiper blade 20 reciprocally wipes a predetermined wiping range (not shown) on the wiping surface WS by the swinging motion of the wiper arm 30. Thereby, rainwater, dust, etc. attached to the wiping surface WS are wiped off.

[0017] Here, as shown in FIGS. 1 to 4, the wiper arm 30 includes an arm shank 40, an arm head 50, a cover member 60, and a tension spring 70.

[0018] [Arm shank] As shown in FIGS. 4 to 6, the arm shank 40 is formed in a substantially rod shape with a tapered end by injection molding a resin material such as plastic. The arm shank 40 has a substantially U-shaped cross section along a direction orthogonal to its longitudinal direction and includes a pair of side wall portions 41. These side wall portions 41 are arranged opposite to each other in the wiping direction of the wiper blade 20 (the vertical direction in FIGS. 1 and 3), that is, in the short direction of the arm shank 40.

[0019] The arm shank 40 also includes a single top wall portion 42. Specifically, the top wall portion 42 is provided on the side opposite to the wiping surface WS side of the pair of side wall portions 41 and connects the pair of side wall portions 41. That is, a pair of side wall portions 41 are integrally provided on both sides in the short direction of the top wall portion 42, whereby the cross section along the direction orthogonal to the longitudinal direction of the arm shank 40 is substantially U-shaped.

[0020] Inside the arm shank 40 surrounded by the pair of side wall portions 41 and the single top wall portion 42, and on the proximal end side of the arm shank 40 (the right side in FIGS. 5 and 6), a connecting shaft 43 that is rotatably attached to the arm head 50 is integrally provided. That is, the proximal end side of the arm shank 40 is rotatably attached to the arm head 50. Specifically, the connecting shaft 43 extends in the short direction of the arm shank 40, and both axial ends of the connecting shaft 43 are respectively connected to the pair of side wall portions 41. The connecting shaft 43 is disposed at a portion of a notch 44 provided on the proximal end side of the top wall portion 42.

[0021] Furthermore, as shown in FIG. 4, the connecting shaft 43 has a shape in which a part of the outer peripheral portion of the cylinder is cut out so that the cross section in the longitudinal direction of the arm shank 40 is substantially D-shaped. That is, the connecting shaft 43 has a flat portion 43a and is formed in a so-called D-cut shape. Thereby, the connecting shaft 43 can be easily attached to the connecting recess 58 of the arm head 50.

[0022] Also, inside the arm shank 40 and on the tip side of the arm shank 40 (the left side in FIGS. 5 and 6), a mounting shaft 45 to which the connecting member 21 of the wiper blade 20 is rotatably mounted is integrally provided. That is, the wiper blade 20 is rotatably mounted on the tip side of the arm shank 40. Specifically, the mounting shaft 45 extends in the short direction of the arm shank 40, and both axial sides of the mounting shaft 45 are respectively connected to a pair of side wall portions 41.

[0023] The mounting shaft 45 is formed in a substantially cylindrical shape, and a connecting portion 21a provided on the connecting member 21 can be mounted on the mounting shaft 45 with one touch by a so-called snap fit as shown by the broken line arrow M in FIG. 5. In other words, the wiper blade 20 can be easily attached to and detached from the arm shank 40, and the maintainability is excellent.

[0024] Furthermore, inside the arm shank 40 and between the connecting shaft 43 and the mounting shaft 45 in the longitudinal direction of the arm shank 40, a shank-side hooking portion 46 on which the tip side (the left side in FIG. 4) of the tension spring 70 is hooked is integrally provided. Specifically, the shank-side hooking portion 46 is provided between the pair of side wall portions 41 and is integrally provided over a total of three locations including these side wall portions 41 and a single top wall portion 42. Thereby, sufficient strength of the shank-side hooking portion 46 is ensured.

[0025] Note that the shank-side hooking portion 46 corresponds to the second hooking portion in the present invention.

[0026] The shank-side engaging portion 46 is disposed at a portion closer to the top wall portion 42 in the height direction of the arm shank 40 (the vertical direction in FIG. 4). That is, the shank-side engaging portion 46 is disposed at a deep portion inside the arm shank 40. As a result, the tip side of the tension spring 70 is also disposed at a portion closer to the top wall portion 42.

[0027] Note that the proximal end side (the right side in FIG. 4) of the tension spring 70 is hooked to the head-side engaging portion 57 (see FIGS. 4 and 8) of the arm head 50. Here, the head-side engaging portion 57 is disposed at a portion closer to the wiping surface WS than the shank-side engaging portion 46 in the height direction of the arm shank 40 (the vertical direction in FIG. 4). As a result, as shown in FIG. 4, the tension spring 70 can be hooked to each of the shank-side engaging portion 46 and the head-side engaging portion 57 while avoiding the connecting shaft 43 and the connecting recess 58.

[0028] Further, as shown in FIGS. 4 to 6, a spring housing recess 47 is provided inside the arm shank 40 and on the proximal end side (the arm head 50 side) of the top wall portion 42.

[0029] The spring housing recess 47 extends in the longitudinal direction of the arm shank 40, and its length dimension is approximately half the length dimension of the top wall portion 42. Further, the spring housing recess 47 is recessed from the inside to the outside of the arm shank 40 with a predetermined depth. Specifically, the thickness dimension of the portion of the top wall portion 42 where the spring housing recess 47 is provided is approximately half the thickness dimension of the portion of the top wall portion 42 where the spring housing recess 47 is not provided.

[0030] And a tapered portion 47a that gently slopes from the portion of the top wall portion 42 where the spring housing recess 47 is provided toward the portion of the top wall portion 42 where the spring housing recess 47 is not provided is provided at the tip side (the left side in FIGS. 4 to 6) of the spring housing recess 47. This suppresses stress concentration at the tip side portion of the spring housing recess 47 in the top wall portion 42.

[0031] Note that the shank-side engaging portion 46 is disposed in the region of the spring accommodation recess 47 in the longitudinal direction of the arm shank 40 and in the vicinity of the tapered portion 47a. That is, since the portion of the top wall portion 42 where the shank-side engaging portion 46 is provided is in the vicinity of the tapered portion 47a, sufficient rigidity is ensured. Therefore, the shank-side engaging portion 46 can be disposed closer to the top wall portion 42. As a result, when the arm shank 40 is raised with respect to the arm head 50 (when in the locked-back state), the spring accommodation recess 47 can accommodate a part of the coil portion 71 of the tension spring 70 without contacting the top wall portion 42 (see FIG. 10).

[0032] Also, inside the arm shank 40 and between the tapered portion 47a and the mounting shaft 45 in the longitudinal direction of the top wall portion 42, a reinforcing rib 48 is provided. The reinforcing rib 48 protrudes toward the inside of the arm shank 40 and is formed in a substantially mesh shape. Specifically, the reinforcing rib 48 is integrally provided over a total of three locations, namely, the pair of side wall portions 41 and the single top wall portion 42. Thereby, the rigidity of the portions of the pair of side wall portions 41 and the single top wall portion 42 where the reinforcing rib 48 is provided is sufficiently increased.

[0033] In this way, the reinforcing rib 48 has a function of reinforcing the arm shank 40 and is disposed relatively close to the mounting shaft 45, the tapered portion 47a, and the shank-side engaging portion 46. That is, the reinforcing rib 48 effectively suppresses the distortion of the portion of the arm shank 40 where the load is likely to be applied.

[0034] Further, as shown in FIGS. 5, 6, and 11, lock claws 49 are integrally provided at the proximal ends (the notch 44 side) of the pair of side wall portions 41, respectively. The pair of lock claws 49 protrude at a predetermined height toward the inside of the pair of side wall portions 41. Specifically, the pair of lock claws 49 are arranged to face each other in the direction in which the connecting shaft 43 extends (the left-right direction in FIG. 11). Further, the lock claw 49 extends in the longitudinal direction of the side wall portion 41, and has a substantially semicircular cross section in a direction orthogonal to the longitudinal direction of the side wall portion 41.

[0035] Here, the pair of lock claws 49 can enter into lock grooves 59 (see FIGS. 7 and 11) provided in the arm head 50 and can be engaged with the lock grooves 59, respectively. Specifically, the lock claw 49 and the lock groove 59 can be engaged with each other when the arm shank 40 is raised with respect to the arm head 50 (when in the lock-back state) (see FIGS. 10 and 11). In this way, the lock claw 49 and the lock groove 59 have a function of maintaining the lock-back state of the wiper device 10.

[0036] When the arm shank 40 is tilted with respect to the arm head 50 to release the lock-back state of the wiper device 10 (to return the wiper device 10 to the use state), the arm shank 40 may be pushed down with a predetermined force toward the wiping surface WS, thereby releasing the engagement between the lock claw 49 and the lock groove 59.

[0037] [Arm head] As shown in FIGS. 7 and 8, the arm head 50 is formed in a substantially rectangular parallelepiped shape by injection molding a resin material such as plastic and extends in the longitudinal direction of the wiper arm 30 (see FIG. 3). The arm head 50 has a pair of side faces 51 directed in the wiping direction of the wiper blade 20 (the up-down direction in FIGS. 1 and 3).

[0038] On the proximal end side (the right side in FIGS. 7 and 8) of the arm head 50, a fixed main body 52 is provided. The fixed main body 52 is a portion fixed to the swing shaft SH (see FIG. 4) by a fastening nut NT, and an annular reinforcing member 53 is inserted (embedded) in the fixed main body 52.

[0039] The reinforcing member 53 is made of aluminum and has a function of reinforcing the resin-made fixed main body 52. Specifically, the swing shaft SH is inserted through the reinforcing member 53, and the tightening force of the fastening nut NT is applied to the reinforcing member 53. Thereby, the arm head 50 can be firmly fixed to the swing shaft SH that is swing-driven so as not to rattle by the fastening nut NT.

[0040] Furthermore, a pair of convex portions 54 are provided on the proximal end side of the arm head 50. These convex portions 54 are respectively provided on a pair of side surface portions 51 that form the arm head 50. Specifically, the convex portions 54 protrude from the side surface portions 51 at a predetermined height in the wiping direction of the wiper blade 20. A cover member 60 can be rotatably attached to these convex portions 54. That is, the pair of convex portions 54 serve as the rotation center of the cover member 60, and the cover member 60 can be opened and closed with respect to the arm head 50 with the pair of convex portions 54 as the rotation center.

[0041] As shown in FIG. 4, when the cover member 60 is closed with respect to the arm head 50, the cover member 60 covers the fastening nut NT. Therefore, the appearance of the wiper device 10 is improved. On the other hand, when the cover member 60 is opened with respect to the arm head 50, the fastening nut NT is exposed to the outside. Therefore, it becomes possible to tighten or loosen the fastening nut NT using a fastening tool (not shown).

[0042] Also, as shown in FIGS. 4, 7, and 8, a groove portion 55 is provided on the tip side (left side in the figure) of the arm head 50 along the longitudinal direction of the arm head 50. The groove portion 55 is disposed at the center in the short side direction of the arm head 50 (the center in the wiping direction of the wiper blade 20), and is disposed in a portion excluding the fixed main body 52 of the arm head 50.

[0043] Then, as shown in FIG. 4, in a state where the wiper device 10 is assembled, the proximal end side (right side in FIG. 4) of the tension spring 70 enters the groove portion 55. Note that the tension spring 70 is in a non-contact state with respect to the arm head 50. Thereby, the tension spring 70 is prevented from protruding largely toward the wiping surface WS side from the arm head 50. Therefore, the overall height of the wiper device 10 is kept low.

[0044] Inside the groove portion 55, a head-side engaging portion 57 formed in a substantially cylindrical shape is integrally provided. Specifically, the head-side engaging portion 57 is disposed at the center in the longitudinal direction of the arm head 50 and in the vicinity of the fixed main body 52. Also, the head-side engaging portion 57 is disposed so as to cross the inside of the groove portion 55 in the short side direction (wiping direction of the wiper blade 20) of the arm head 50. Thereby, the proximal end side of the tension spring 70 can be hooked on the head-side engaging portion 57.

[0045] Note that the head-side engaging portion 57 corresponds to the first engaging portion in the present invention.

[0046] Furthermore, as shown in FIG. 7, a connecting recess 58 for rotatably supporting the connecting shaft 43 of the arm shank 40 is provided on the tip side of the arm head 50. Specifically, the connecting recess 58 is disposed on the arm shank 40 side (left side in the figure) rather than the head-side engaging portion 57 in the longitudinal direction of the arm head 50. In this way, the proximal end side (right side in FIG. 4) of the arm shank 40 is rotatably attached to the arm head 50.

[0047] More specifically, on the side opposite to the wiping surface WS side of the connecting recess 58 (the upper side in FIGS. 4 and 7), an opening 58a is provided on the mounting side where the connecting shaft 43 is mounted. And in the state where the wiper device 10 is assembled, the opening 58a is covered by the cover member 60. Thereby, it is possible to prevent the connecting shaft 43 from coming off from the connecting recess 58. Further, since the opening 58a is covered by the cover member 60, the surface of the wiper device 10 becomes smooth, and thus the generation of wind noise is further suppressed.

[0048] Also, as shown in FIGS. 7 and 11, lock grooves 59 are respectively provided on a pair of side portions 51 that form the arm head 50. Specifically, when the arm shank 40 is raised with respect to the arm head 50 (when in the lock-back state), a pair of lock claws 49 provided on the arm shank 40 respectively enter and engage with the lock grooves 59.

[0049] The lock grooves 59 are arranged between the fixed main body 52 and the connecting recess 58 in the longitudinal direction of the side portion 51 (the left-right direction in FIG. 7). And each lock groove 59 is provided so as to be recessed at a predetermined depth toward a groove portion 55 provided at the center in the short-side direction of the arm head 50.

[0050] Furthermore, on the side opposite to the wiping surface WS side of the lock groove 59 (the upper side in the figure), an introduction convex portion 59a is provided so as to be aligned with the lock groove 59. That is, the lock claw 49 provided on the arm shank 40 can be engaged with the lock groove 59 by getting over the introduction convex portion 59a.

[0051] Here, as shown in FIG. 11, taper surfaces TP are respectively formed on the introduction side (the upper side in the figure) and the lock groove 59 side (the lower side in the figure) of the introduction convex portion 59a. Thereby, by operating the arm shank 40 with a relatively light operating force, the lock claw 49 can easily get over the introduction convex portion 59a.

[0052] When the wiper device 10 is in the lock-back state (see FIG. 10), the spring force of the tension spring 70 acts in the direction of tipping the arm shank 40. However, with only the spring force of the tension spring 70, the locking claw 49 cannot overcome the introduction convex portion 59a and does not come out of the locking groove 59. That is, unless an external force (operating force) is applied in addition to the spring force of the tension spring 70, the lock-back state of the wiper device 10 is not released and is maintained. Therefore, the replacement work of the wiper blade 20 and the like can be easily performed, and the maintainability is improved.

[0053] Here, the pair of locking claws 49 provided on the arm shank 40 will overcome the introduction convex portion 59a while bending the pair of side wall portions 41. However, as shown in FIGS. 6 and 11, the pair of locking claws 49 are arranged in the vicinity of the notch portion 44 of the arm shank 40. Therefore, the portion of the side wall portion 41 where the locking claws 49 are provided can be elastically deformed relatively easily.

[0054] [Tension spring] As shown in FIGS. 4 and 9, a tension spring 70 for elastically contacting the wiper blade 20 with the wiping surface WS is provided between the arm head 50 and the arm shank 40. Specifically, the tension spring 70 includes a coil portion 71 formed by forming a hard steel wire or the like in a coil shape. Further, a first hook portion 72 that is hooked on the head side hook portion 57 is provided on the base end side (right side in the figure) of the coil portion 71, and a second hook portion 73 that is hooked on the shank side hook portion 46 is provided on the tip end side (left side in the figure) of the coil portion 71.

[0055] Note that the tension spring 70 corresponds to the spring in the present invention, and the first hook portion 72 corresponds to the hook portion in the present invention.

[0056] Further, in the longitudinal direction of the tension spring 70, a straight portion 74 extending in the extending direction of the coil portion 71 is integrally provided between the coil portion 71 and the first hook portion 72. Specifically, the extending direction of the coil portion 71 and the extending direction of the straight portion 74 are parallel to each other.

[0057] Also, a first bent portion B1 and a second bent portion B2 are provided between the straight portion 74 and the coil portion 71, and an inclined portion 75 is provided between the first bent portion B1 and the second bent portion B2. The inclined portion 75 and the first and second bent portions B1 and B2 disposed at both ends thereof have a function of shifting and parallelizing the axis C1 of the coil portion 71 and the axis C2 of the straight portion 74 with respect to each other.

[0058] In this way, by providing a plurality of bent portions (the first and second bent portions B1 and B2) and the inclined portion 75, as shown in FIGS. 4 and 10, the first hook portion 72 and the second hook portion 73 of the tension spring 70 can be hooked on the head-side hooking portion 57 and the shank-side hooking portion 46, respectively, while avoiding the connecting shaft 43 and the connecting recess 58.

[0059] Further, as shown in FIG. 4, when the arm shank 40 is tilted with respect to the arm head 50 (when the wiper device 10 is in a use state), the straight portion 74 of the tension spring 70 is parallel to the extending direction of the pair of side wall portions 41. Specifically, the straight portion 74 is disposed along the side wall end faces EF (see FIG. 6) provided on the pair of side wall portions 41 when the arm shank 40 is tilted with respect to the arm head 50.

[0060] Here, the side wall end faces EF provided on the pair of side wall portions 41 are provided on the wiping surface WS side of the pair of side wall portions 41 and can face the wiping surface WS. Specifically, when the arm shank 40 is tilted with respect to the arm head 50, the pair of side wall end faces EF face the wiping surface WS (see FIG. 4).

[0061] On the other hand, as shown in FIG. 10, when the arm shank 40 is raised with respect to the arm head 50 (when in the locked-back state), a part of the coil portion 71 forming the tension spring 70 (the side opposite to the wiping surface WS side) is accommodated in the spring accommodation recess 47 of the arm shank 40, and when the arm shank 40 is raised with respect to the arm head 50 and viewed from the direction in which the pair of side wall portions 41 face each other, the entire tension spring 70 is hidden by the pair of side wall portions 41.

[0062] [Regarding the locked-back operation] As shown in FIGS. 10 and 11, when the arm shank 40 is raised with respect to the arm head 50, a pair of locking claws 49 provided on the arm shank 40 respectively enter a pair of locking grooves 59 provided on the arm head 50. As a result, the tension spring 70 approaches the top wall portion 42 (spring accommodation recess 47), and the locked-back state of the wiper device 10 is maintained.

[0063] Note that the locked-back angle of the wiper device 10, that is, the angle on the narrow-angle side with respect to the wiping surface WS (see FIGS. 2 and 4) of the arm shank 40, is about 20 degrees. Here, the locked-back angle is made small at about 20 degrees. This is to prevent the arm shank 40 from contacting the rear spoiler (not shown) provided on the vehicle side when the wiper device 10 is hidden by the rear spoiler (to prevent damage). Note that since the wiper blade 20 can be easily removed from the arm shank 40 (snap-fit structure), even if the locked-back angle is about 20 degrees, the maintainability of the wiper device 10 does not deteriorate.

[0064] When the wiper device 10 is in the lock-back state, the tension spring 70 assumes the posture as shown in FIG. 10. Specifically, a part of the coil portion 71 of the tension spring 70 (the upper part in the figure) is received in the spring housing recess 47 of the arm shank 40. That is, a part of the coil portion 71 enters into the portion (spring housing recess 47) that is thinner than the other part of the top wall portion 42. At this time, the coil portion 71 is in a non-contact state with respect to the top wall portion 42. Therefore, damage to both the top wall portion 42 and the coil portion 71 is prevented.

[0065] Furthermore, when the wiper device 10 is in the lock-back state and the arm shank 40 is viewed from the direction in which the pair of side wall portions 41 face each other, as shown in FIG. 10, the entire tension spring 70 is completely hidden by the pair of side wall portions 41.

[0066] On the other hand, to place the arm shank 40 in a state where it is tilted with respect to the arm head 50, that is, to put the wiper device 10 in the use state, an operating force is applied to the arm shank 40 to tilt the arm shank 40 with respect to the arm head 50. As a result, the lock claw 49 gets over the introduction convex portion 59a and disengages from the lock groove 59. Therefore, the tension spring 70 moves away from the top wall portion 42 (spring housing recess 47) and assumes the state shown in FIG. 4 (the use state of the wiper device 10).

[0067] Here, as shown in FIG. 4, when the arm shank 40 is viewed from the direction in which the pair of side wall portions 41 face each other, the entire tension spring 70 is substantially hidden by the side wall portion 41. Specifically, at least a part of the straight portion 74 of the tension spring 70 is disposed inside the arm shank 40 rather than the side wall end face EF of the pair of side wall portions 41. Therefore, the axially proximal end side (the right side in FIG. 4) of the coil portion 71 does not protrude significantly toward the wiping surface WS.

[0068] Thus, in the locked-back state of the wiper device 10, a part of the coil portion 71 is released (accommodated) inside the spring accommodation recess 47, and in the use state of the wiper device 10, the axially proximal end side of the coil portion 71 does not protrude greatly toward the wiping surface WS. This is achieved by providing the first and second bending portions B1 and B2 on the tension spring 70 and providing the straight portion 74 and the inclined portion 75. Therefore, the height of the wiper device 10 from the wiping surface WS can be made lower than before, and thus the wind noise that may occur during high-speed driving or the like can be effectively reduced.

[0069] Note that depending on the vehicle type on which the wiper device 10 is mounted, there are some with a large curvature of the wiping surface WS. In this case, as shown by the dashed arrow R in FIG. 4, the wiper blade 20 swings greatly about the mounting axis 45 with respect to the arm shank 40. In the wiper device 10 of the present embodiment, the proximal end side (the right side in FIG. 4) of the wiper blade 20 can enter the inside of the arm shank 40 surrounded by the pair of side wall portions 41 and the single top wall portion 42, and as shown in the enlarged portion surrounded by the dashed line in FIG. 4, the proximal end side of the wiper blade 20 enters the inside of the arm shank 40. Thus, the wiper device 10 can also cope with a large curvature of the wiping surface WS.

[0070] As described in detail above, according to the wiper device 10 of the present embodiment, the arm head 50 includes a head-side hook portion 57 on which the proximal end side of the tension spring 70 is hooked. The arm shank 40 includes a pair of side wall portions 41 arranged to face each other in the wiping direction of the wiper blade 20, a top wall portion 42 provided on the side opposite to the wiping surface WS side of the pair of side wall portions 41 and connecting the pair of side wall portions 41, a shank-side hook portion 46 provided between the pair of side wall portions 41 and on which the distal end side of the tension spring 70 is hooked, and a spring accommodation recess 47 provided in the top wall portion 42 and capable of accommodating a part of the coil portion 71 of the tension spring 70. When the arm shank 40 is raised with respect to the arm head 50, a part of the coil portion 71 of the tension spring 70 is accommodated in the spring accommodation recess 47, and when the arm shank 40 is raised with respect to the arm head 50 and the arm shank 40 is viewed from the direction in which the pair of side wall portions 41 face each other, the tension spring 70 is hidden by the pair of side wall portions 41.

[0071] As a result, the tension spring 70 does not protrude greatly toward the wiping surface WS, the height of the wiper device 10 from the wiping surface WS can be made lower, and thus the wind noise generated by the wiper device 10 during high-speed running of the vehicle or the like can be further suppressed. Therefore, when applied to a vehicle powered by an electric motor with low noise such as an electric vehicle, it is possible to reduce the wind noise transmitted into the vehicle and improve the comfort of the vehicle interior.

[0072] Further, according to the wiper device 10 of the present embodiment, side wall end faces EF capable of facing the wiping surface WS are respectively provided on the wiping surface WS sides of the pair of side wall portions 41. The tension spring 70 includes a coil portion 71 formed in a coil shape, a first hook portion 72 provided on the proximal end side of the coil portion 71 and hooked on the head-side hook portion 57, and a straight portion 74 provided between the coil portion 71 and the first hook portion 72 and extending in the extending direction of the coil portion 71. When the arm shank 40 is tilted with respect to the arm head 50, at least a part of the straight portion 74 is arranged inside the arm shank 40 rather than the side wall end face EF.

[0073] As a result, the tension spring 70 does not need to protrude significantly from the arm shank 40 toward the wiping surface WS, and this also makes it possible to further reduce the overall height of the wiper device 10.

[0074] Furthermore, according to the wiper device 10 of the present embodiment, the proximal end side of the wiper blade 20 can enter the inside of the arm shank 40 surrounded by the pair of side wall portions 41 and the top wall portion 42.

[0075] As a result, the wiper device 10 can easily cope with a wiping surface WS having a large curvature.

[0076] Also, according to the wiper device 10 of the present embodiment, by reducing the height from the wiping surface WS, the load due to the traveling wind acting on the wiper device 10 can be reduced, the durability of the wiper device 10 can be improved, and the manufacturing energy of the wiper device 10 can be reduced. Therefore, it is possible to achieve particularly Goal 7 (ensuring access for all people to affordable, reliable, and sustainable modern energy) and Goal 13 (taking urgent measures to mitigate climate change and its impacts) in the Sustainable Development Goals (SDGs) defined by the United Nations.

[0077] The present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made without departing from the gist thereof. For example, in the above-described embodiment, the wiper device 10 has been described by taking as an example the one that wipes the windshield (rear windshield) provided on the back door of a vehicle such as an automobile. However, the present invention is not limited to this, and for example, it can also be applied to a wiper device that wipes the front windshield of a vehicle such as an automobile, or the glass of an aircraft, a railway vehicle, a construction machine, or the like.

[0078] In addition, the material, shape, dimensions, number, installation location, etc. of each component in the above-described embodiment are arbitrary as long as the present invention can be achieved, and are not limited to the above-described embodiment.

Explanation of Reference Numerals

[0079] 10: Wiper device, 20: Wiper blade, 21: Connecting member, 21a: Connecting part, 22: Blade rubber, 23: Cover, 24: End cap, 30: Wiper arm, 40: Arm shank, 41: Side wall part, 42: Top wall part, 43: Connecting shaft, 43a: Flat part, 44: Notch, 45: Mounting shaft, 46: Shank side engaging part (second engaging part), 47: Spring housing recess, 47a: Taper part, 48: Reinforcing rib, 49: Lock claw, 50: Arm head, 51: Side surface part, 52: Fixed body, 53: Reinforcing member, 54: Protrusion, 55: Groove part, 57: Head side engaging part (first engaging part), 58: Connecting recess, 58a: Opening, 59: Lock groove, 59a: Introducing protrusion, 60: Cover member, 70: Tension spring (spring), 71: Coil part, 72: First hook part (hook part), 73: Second hook part, 74: Straight part, 75: Inclined part, B1: First bending part, B2: Second bending part, EF: Side wall end face, NT: Fastening nut, SH: Oscillation shaft, TP: Taper surface, WS: Wiping surface

Claims

1. An arm head fixed to a swing shaft, An arm shank with its proximal end rotatably attached to the arm head, A wiper blade attached to the distal end side of the arm shank, A spring provided between the arm head and the arm shank, pressing the wiper blade against the wiping surface, A wiper device having, The arm head, Comprises a first hook portion on which the proximal end side of the spring is hooked, The arm shank, A pair of side wall portions disposed opposite to each other in the wiping direction of the wiper blade, A top wall portion provided on the side opposite to the wiping surface side of the pair of side wall portions, connecting the pair of side wall portions, A second hook portion provided between the pair of side wall portions, on which the distal end side of the spring is hooked, A spring accommodation recess provided on the top wall portion, capable of accommodating at least a part of the spring, Having, When the arm shank is raised with respect to the arm head, at least a part of the spring is accommodated in the spring accommodation recess, and when the arm shank is raised with respect to the arm head and the arm shank is viewed from the direction in which the pair of side wall portions face each other, the spring is hidden by the pair of side wall portions, Wiper device.

2. In the wiper device according to claim 1, On the wiping surface side of the pair of side wall portions, side wall end faces capable of facing the wiping surface are respectively provided, The spring, A coil portion formed in a coil shape, A hook portion provided on the proximal end side of the coil portion, hooked on the first hook portion, A straight portion provided between the coil portion and the hook portion, extending in the extending direction of the coil portion, Comprising, When the arm shank is tilted with respect to the arm head, at least a part of the straight portion is disposed inside the arm shank rather than the side wall end face, Wiper device.

3. The proximal end side of the wiper blade can enter the inside of the arm shank surrounded by the pair of side wall portions and the top wall portion, The wiper device according to claim 1 or claim 2.

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