At a glance
| Patent number | CN110833685B (application CN201911275760) |
| Type | China invention patent (发明专利) - protects method and structure |
| Original title | Dual-purpose shoes and folding pulley device thereof (两用鞋及其折叠式滑轮装置) |
| Patent owner | Jinjiang Tengqiang Shoes Co ltd |
| Inventors | Xiao Renqiang |
| Filing date | 2019-12-12 |
| Grant date | 2024-10-29 |
| Status (China) | In force - valid until at most 2039-12-12, provided annual fees are paid |
| Patent family | Chinese filings only - no US, European, Japanese, PCT or other filings listed |
| Cited by | 0 later documents |
| Source | Google Patents (search for CN110833685B) |
What the claims cover, in plain language
Claim 1 defines a folding pulley device comprising a front wheel frame, rear wheel frame, shell seat, linkage frame, and switch mechanism. The linkage frame has horizontally parallel shafts (locking movable, transmission front, middle fixed). The shell seat has specific limiting holes (horizontal, vertical, arc-shaped) and rotating fixed shafts. A tension spring connects the middle and first rotating shafts. The wheel frames connect to these shafts. The switch mechanism moves the locking shaft between folding and unfolding clamp holes to maintain the device’s state.
Claim 2 specifies the shell seat consists of a shell cover and a shell seat body formed by integral injection molding, sealing the installation chamber.
Claim 3 details the position of the arc-shaped limit holes relative to the rotating shafts, ensuring the front and rear wheel frames move toward each other when folded.
Claims 4-7 describe additional structural features: embedding holes for compression springs, T-shaped holes and heads for trigger rods, safety blocks and holes for preventing accidental release, and stoppers and protrusions to fix the guide seat within the installation chamber.
Claim 8 covers the dual-purpose shoe itself, incorporating the device from Claims 1-7 onto a sole. It specifies recesses on the left and right sides of the sole’s middle part to accommodate the folded wheel frames, a matching hole at the rear for the switch mechanism, and ensures the top surface of the shell seat is flush with the sole’s top surface.
This is a simplified reading for orientation only. The legal scope is defined by the exact claim wording in the official Chinese document.
What this means for US production
This patent was filed only in China and is currently in force. Making or selling this specific design in China requires the owner’s permission. Since there are no US counterparts, the patent does not directly restrict manufacturing or sales in the United States based on this document alone.
Two points to settle early:
- Other patents may exist. Footwear with integrated wheels is a competitive field. Major brands like Heelys hold various patents on wheel mechanisms and sole structures. A freedom-to-operate (FTO) review is essential to ensure the specific folding linkage and locking mechanism do not infringe on existing US utility or design patents.
- Structural Integrity. The design relies on injection-molded shells and metal shafts. Ensuring these components withstand repeated folding cycles and user weight requires rigorous prototyping.
Customization and manufacturing
What can be customized
| Area | Options |
|---|---|
| Sole Material | EVA, rubber, or polyurethane blends depending on durability needs |
| Wheel Type | Inline skate wheels, rollerblade style, or custom diameter/durometer |
| Colorways | Shell seat, wheel frames, and upper shoe materials can be color-matched |
| Size Range | Child, youth, adult unisex, or gender-specific sizing |
| Closure System | Laces, velcro, or slip-on designs compatible with the heel mechanism |
| Spring Tension | Adjusted for ease of switching vs. secure locking |
Things to plan for (US market)
- CPSC Safety Standards: General toy and consumer product safety rules apply if marketed to children.
- ASTM F1497: Standard specification for performance requirements of inline skating helmets and accessories (relevant for marketing claims about safety).
- California Prop 65: Screening of plastics and metals used in the shell and wheels for restricted substances.
- Labeling: Proper care instructions and warning labels regarding the use of the folding mechanism.
How a project runs
- Inquiry - Define target demographic, size range, and aesthetic preferences.
- Design Adaptation - Modify the patent’s basic structure to fit your brand’s upper shoe design and sole profile.
- Prototype - Create 3D printed or CNC machined samples to test the folding action and locking security.
- Testing - Conduct cycle testing (opening/closing) and load-bearing tests to ensure the mechanism does not fail under stress.
- Production - Injection molding for plastic parts, stamping for metal shafts, and assembly with the shoe upper.
Quantities & timeline
Injection molds for the shell seat and wheel frames are complex due to the internal cavities and moving parts. Metal shafts require precision machining or stamping. Assembly involves fitting the linkage frame into the sole before attaching the upper. Development typically takes 3-6 months for tooling and validation. Send us your target sizes, material preferences, quantity estimates, and desired launch date and we will reply with options.
Patent drawings
Drawings reproduced from the public patent document for reference.
