Obviousness

To analyze the obviousness of US patent 8104492 under 35 U.S.C. § 103, we must consider whether the claimed invention, as a whole, would have been obvious to a person having ordinary skill in the art (PHOSITA) at the time of the invention (priority date May 5, 2008), by combining existing prior art references. The analysis will identify combinations of prior art references that teach all elements of independent Claim 1 of US8104492 and articulate the motivation for a PHOSITA to combine these references.

Independent Claim 1 Analysis

Claim 1 of US8104492 describes an umbrella comprising:

1. A main pole.
2. A sliding member on the main pole, capable of movement between upper and lower locations.
3. A locking means for releasably securing the sliding member.
4. An umbrella canopy with a central region.
5. An arm extending radially from the canopy's central region, with its outer end associated with the sliding member.
6. A brace having a first end pivotably attached to an upper portion of the pole (above the sliding member) and a second end pivotably attached to the arm.
7. A winding mechanism with a winder hub, mounted to and movable with the sliding member.
8. A line wound around the winder hub, extending along the arm to engage the umbrella canopy.
9. The winding mechanism's rotation tensions/relaxes the line to open/close the canopy.
10. The angle of the canopy is controlled by moving the sliding member along the main pole.

Relevant Prior Art References

Based on the "Citations" section of US8104492, and verifying their priority dates precede May 5, 2008:

• US5937882A (Harbaugh; Kenneth A.): "Umbrella with side support for tilting and opening." (Priority date: 1998-04-09)
• US7156114B2 (Chong-Yi Lo): "Angle adjusting device for the canopy of a hang umbrella." (Priority date: 2005-02-02)
• US20020129847A1 (Ma Mark J.S.): "Parasol opening device." (Priority date: 2001-03-13)
• US5284171A (Liu Chin Hsiang): "Sunshade opening and supporting device." (Priority date: 1992-12-07)
• US20020121297A1 (Li Wanda Yiing): "Operation device for outdoor umbrella." (Priority date: 2001-03-02)

Obviousness Combination: US5937882A (Harbaugh) + US7156114B2 (Lo) + US20020129847A1 (Ma)

This combination of references renders Claim 1 of US8104492 obvious.

1. Primary Reference: US5937882A (Harbaugh)
Harbaugh discloses a basic "umbrella with side support for tilting and opening," which serves as an excellent starting point for a PHOSITA. It includes:

• A support pole (main pole) and an umbrella canopy.
• A slider (sliding member) mounted on the support pole for vertical movement.
• A separate support member (arm) pivotally connected to the support pole and to an upper portion of the umbrella canopy.
• A crank mechanism mounted on the support pole that operates a cable to move the slider vertically.
• Another cable, operated by the same crank mechanism, extends along the support member to open and close the umbrella canopy.
• The vertical movement of the slider also causes the angle of the umbrella canopy to tilt.

While Harbaugh teaches many elements, US8104492 explicitly identifies a drawback in such existing designs: "The crank mechanism is mounted to the main pole, and the rope moves along a complex path with many turning points. This arrangement requires more winding force, and the rope can easy bind and wear, adversely affecting the umbrella's operation." The subsequent references provide solutions to these specific problems.

2. Secondary Reference: US7156114B2 (Lo)
Lo describes an "angle adjusting device for the canopy of a hang umbrella" that directly addresses the specific brace configuration of Claim 1. It discloses:

• A main pole.
• An upper sleeve fixed to the main pole (analogous to the "cap" in US8104492).
• A lower sleeve slidably fitted on the main pole (sliding member).
• A support arm having a first end pivotally connected to the lower sleeve and a second end connected to the canopy of the umbrella.
• A tilt rod (brace) having a first end pivotally connected to the upper sleeve and a second end pivotally connected to the support arm.

This reference precisely teaches the "brace having a first end pivotably attached to an upper portion of the pole above the sliding member and a second end pivotably attached to the arm" as claimed in US8104492.

Motivation to combine Harbaugh with Lo:
A PHOSITA, aiming to improve the angle adjustment and stability of the offset umbrella described by Harbaugh, would be motivated to incorporate the more robust and articulated tilt mechanism taught by Lo. Lo's design provides a clear separation of the support arm's connection to the sliding member from the brace's connection to a fixed upper point on the main pole, offering enhanced stability and smoother angular adjustment compared to Harbaugh's simpler support member arrangement. This combination directly addresses the structural elements for precise canopy angle control through the sliding member.

3. Secondary Reference: US20020129847A1 (Ma)
Ma discloses a "parasol opening device" that addresses the problem of the winding mechanism's location and the simplification of the line path. It includes:

• A tubular main pole.
• A sliding sleeve slidably mounted on the main pole.
• An operating unit mounted on the sliding sleeve.
• This "operating unit" includes a crank handle and a winding reel (winder hub), clearly demonstrating a winding mechanism mounted to and movable with the sliding member.
• A latching device (locking means) for securing the sliding sleeve on the main pole.
• A line extending from the winding reel on the sliding sleeve to open and close the umbrella canopy.

Motivation to combine Harbaugh and Lo with Ma:
The '492 patent explicitly aims to simplify the line path and reduce winding force by having the "winding element is mounted to the sliding member and is movable therewith." Ma directly provides this solution by mounting the "operating unit" (winding mechanism) onto the "sliding sleeve" (sliding member), simplifying the rope's path to the canopy. A PHOSITA would be motivated to adopt Ma's arrangement into the Harbaugh/Lo combination to achieve the known benefits of a shorter, less complex rope path, which includes reducing friction, wear, and the force required to open and close the canopy. The inclusion of a locking means for the sliding member, explicitly taught by Ma, is a routine design choice for any adjustable sliding mechanism to prevent unwanted movement and secure the desired position. US5284171A (Liu) also discloses conventional cam-based locking means for a sliding member, demonstrating this as a common feature in the art.

Conclusion on Obviousness

Combining the teachings of US5937882A (Harbaugh), US7156114B2 (Lo), and US20020129847A1 (Ma) would render Claim 1 of US8104492 obvious to a PHOSITA. Harbaugh provides the core offset umbrella structure with canopy angle adjustment via a sliding member. Lo provides the specific and improved brace configuration for stable angle adjustment. Ma provides the critical feature of integrating the winding mechanism with the sliding member, along with a locking means, to simplify canopy operation. The motivations to combine these references are clear: to improve the stability and precise control of the canopy's angle and to simplify and make more efficient the mechanism for opening and closing the canopy, addressing known problems in the art such as complex rope paths and burdensome operation.