This application claims priority to Taiwanese Application No. 100223155, filed on Dec. 8, 2011.
1. Field of the Invention
The invention relates to a sunshade assembly, and more particularly to a sunshade assembly having guide rails and adapted for placement on an inside surface of a window of a vehicle or a building.
2. Description of the Related Art
Currently, there are various types of sunshade assemblies sold on the market, wherein a conventional track type sunshade assembly has two guide rails respectively disposed on two lateral sides of a sunshade curtain. In use, the sunshade curtain can be extended or retracted along the two guide rails. In order to adjust a sun shading area, manufacturers currently have developed various structures that allow users to freely pull and stop the sunshade curtain at any desired extended position so as to flexibly adjust an extent of sun shading. However, when the sunshade curtain is extended, the conventional sunshade assembly is limited by the structural design thereof, and thus, it is required to apply a pull force to the sunshade curtain at a central position of a free end of the sunshade curtain so as to smoothly extend the sunshade curtain along the guide rails. If the pull force is applied at a position deviating from the central position of the free end of the sunshade curtain, the pull force will be unevenly applied to the sunshade curtain, and the sunshade curtain tends to be obliquely taken up or stuck between the guide rails. Thus, the smoothness of take-up and extension of the sunshade curtain will be adversely influenced, and at the worst, extension of the sunshade curtain may not be possible, thereby causing inconvenience to users.
Therefore, an object of the present invention is to provide a sunshade assembly that can alleviate at least one of the aforesaid drawbacks of the prior art.
According to the present invention, a sunshade assembly includes two spaced-apart mounting seats, a winding shaft, a sunshade curtain, a pull rod, two guide rail units, a link unit, and a resistance unit. The winding shaft is mounted rotatably between the mounting seats. The sunshade curtain is extendably wound around the winding shaft. The pull rod is connected to one end of the sunshade curtain that is distal from the winding shaft. Each of the two guide rail units includes a guide rail that has a guide surface extending along the length of the guide rail. The link unit includes a connecting shaft mounted rotatably to the pull rod and having two opposite ends, and two guide wheels respectively attached to the two opposite ends of the connecting shaft. Each of the guide wheels has a rolling surface to roll on the guide surface of one of the guide rails. One of the rolling surface and the guide surface has a guide groove. The other one of the rolling surface and the guide surface protrudes into the guide groove. The resistance unit includes a base mounted to the pull rod and frictionally contacting the connecting shaft to provide a resisting force against rotation of the connecting shaft.
Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiments with reference to the accompanying drawings, of which:
Before the present invention is described in greater detail, it should be noted that the same reference numerals have been used to denote like elements throughout the specification.
Referring to
In this preferred embodiment, the sunshade assembly includes amounting unit 2, a sunshade unit 3, two guide rail units 1, a link unit 4, and a resistance unit 5.
The mounting unit 2 includes two spaced-apart mounting seats 21. Alternatively, the two mounting seats 21 may be integrally formed. Since the feature of this invention does not reside in the configuration of the mounting seats 21, which may be readily appreciated by those skilled in the art, details of the same are omitted herein for the sake of brevity.
The sunshade unit 3 includes a winding shaft 31 rotatably mounted between the mounting seats 21, a sunshade curtain 32 extendably wound around the winding shaft 31, and a pull rod 33 connected to one end 321 of the sunshade curtain 32 that is distal from the winding shaft 31. Preferably, the pull rod 33 is a hollow rod and extends along the width direction of the sunshade curtain 32. Preferably, the sunshade unit 3 further includes at least one resilient member (not shown) having two opposite ends. One of the opposite ends is fixed and the other of the opposite ends is connected to the winding shaft 31 so that the resilient member provides a resilient force to drive rotation of the winding shaft 31 to have a tendency towards the take-up state, i.e., the sunshade curtain 32 tends to be wound around the winding shaft 31 without an applied force.
In this embodiment, each of the guide rail units 1 includes a guide rail 12 having a guide surface 121 that extends along the length of the guide rail 12 and that has a guide groove 122. Preferably, each of the guide rail units 1 further includes an elongate frame 11 of substantially U-shaped cross section that has a main wall 111, and first and second sidewalls 112, 113 extending transversely and respectively from two opposite ends of the main wall 11 towards the other one of the guide rail units 1. The main wall 111 and the first and second sidewalls 112, 113 of each guide rail unit 1 cooperatively define a rail groove 114 having an opening end. The opening ends of the rail grooves 114 of the two guide rail unit 1 face each other. The guide rail 12 is lengthwise disposed on the first sidewall 112. Alternatively, the guide rail 12 may be disposed on the second sidewall 113 or each of the first and second sidewalls 112, 113 may be mounted with a respective guide rail 12. The frame 11 and the guide rail 12 of each of the guide rail units 1 may be integrally formed. Thus, the arrangement of the guide rail(s) 12 according to the present invention can be adjusted based on an intended applied situation and are not limited to this preferred embodiment.
The link unit 4 includes a connecting shaft 41 mounted rotatably in the pull rod 33 and having two opposite ends 410, 411, and two guide wheels 42 respectively attached to the two opposite ends 410, 411 of the connecting shaft 41 and respectively disposed in the rail grooves 114. Each of the guide wheels 42 has a rolling surface 421 to roll on the guide surface 121 and received in the corresponding the guide rail 12.
In this preferred embodiment, the guide groove 122 of the guide surface 121 of each of the guide rails 12 is designed by an arcuate groove-defining wall surface and the rolling surface 421 of the corresponding guide wheel 42 radially and outwardly protrudes into the guide groove 122.
The rolling surface 421 and the corresponding guide surface 121 maybe configured to have other shapes, such as trapezoid and complementary trapezoid contours, V and complementary V contours, U and complementary U contours, and complementary saw-toothed contours, as long as they mesh with each other.
When conducting adjustment of the sunshade curtain 32, the guide wheels 42 are together rotatable with the connecting shaft 41 and simultaneously moveable backward and forward along the guide rails 12. Since each of the rolling surfaces 421 protrudes into the corresponding guide groove 122, each of the guide wheels 42 can stably move along the corresponding guide rail 12 without swerving and the connecting shaft 41 can be moved in parallel with and relative to the winding shaft 31. Preferably, each of the guide wheels 42 may be formed into a caster or a friction roller that may be made of a flexible material selected from the group consisting of silicone, rubber and combinations thereof, while each of the guide rails 12 may be made from a material having a hardness higher than that of the flexible material, such as plastic. Alternatively, each of the guide rails 12 may be made of the flexible material and each of the guide wheels 42 may be made of the material having the hardness higher than that of the flexible material. The choices of the materials for making the guide wheels 42 and the guide rails 12 preferably complement each other, thereby reducing noise and providing a frictional resistance force when the sunshade curtain 32 is adjusted.
Further referring to
Referring to
The connecting shaft 41 is inserted through the insert portion 514. Moreover, the open portion 515 has a width narrower than that of the insert portion 514 such that the connecting rod 41 is limited in the insert portion 514 and sandwiched between the base walls 511. Each base wall 511 includes a threaded hole 516 communicating with the open portion 515. The threaded hole 516 is distal from the connecting wall 512.
The fastener 52 secures the base 51 to the pull rod 33. In this embodiment, the fastener 52 is configured as a bolt that extends through the pull rod 33 and that engages threadedly with the threaded holes 516 in the base walls 511 for securing the base 51 to the pull rod 33. In actual implementation, the number of the fastener 52 may be increased.
In this embodiment, the distance of the connecting wall 512 from the end 321 of the sunshade curtain 32 is longer than that of the fastener 52 that engages threadedly the base walls 511 from the end 321 of the sunshade curtain 32. Alternatively, the distance of the connecting wall 512 from the end 321 of the sunshade curtain 32 may be shorter than that of the fastener 52 that engages threadedly the base walls 511 from the end 321 of the sunshade curtain 32. Besides, the base 51 may be disposed outside the pull rod 33.
In use, the pull rod 33 can be pushed or pulled relative to the winding shaft 31. Therefore, the sunshade curtain 32 can be extended or retracted relative to the winding shaft 31 between an extended position shown in
Referring to
Specifically, the connecting shaft 41 that is inserted in the base 51 frictionally contacts the base walls 511. After the fastener 52 engages threadedly with the base walls 511, the connecting shaft 41 is clamped between the base walls 511. Hence, during movement of the pull rod 33, the friction resistance force between the connecting shaft 41 and the base walls 511 has to be overcome so that the connecting shaft 41 is able to be concomitantly rotated with the guide wheels 42. When the sunshade curtain 32 is extended to any desired extended position by pulling the pull rod 33, after the pull rod 33 is released, the pull rod 33 is stopped together with the sunshade curtain 32 at the desired extended position because a retracting force of the winding shaft 31 is less than the friction resistance force between the connecting rod 41 and the base walls 511, thereby achieving the pull and stop function with relative ease. In addition, because of a frictional contact existing between the guide wheel 42 and the guide rail 12, the frictional force generated therebetween can resist the retracting force of the winding shaft 31 as well, so that the sunshade curtain 32 can be maintained at any desired extended position.
Referring to
To sum up, by virtue of the engagement design of each of the guide rails 12 and the corresponding guide wheel 42, the connecting shaft 41 connected to the guide wheels 42 can be smoothly rotated so as to prevent the guide wheels 42 from being stuck in the guide rails 12 due to a noncentral pulling force. Therefore, the sunshade curtain 32 can be smoothly wound and unwound, thereby increasing convenience to users. Furthermore, according to a design of the resistance unit 5, the base 51 provides the connecting shaft 41 with the resisting force so that the pull rod 33 can be stopped immediately when the pulling or pushing force is released and so that the sunshade curtain 32 can be pulled and stopped at any desired extended position.
While the present invention has been described in connection with what are considered the most practical and preferred embodiments, it is understood that this invention is not limited to the disclosed embodiments but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.
Number | Date | Country | Kind |
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100223155 | Dec 2011 | TW | national |