Manually pushed broadcast spreader with two counter-rotating plates
A manually driven broadcast spreader for granular particulate materials featuring two rotatable impeller plates mounted beneath the hopper. One plate rotates clockwise and the other counterclockwise to produce a more symmetric left/right distribution; ports in the hopper feed each plate and can be adjusted or blocked from the push-handle without releasing the grips. Intended users include groundskeepers, landscapers and small-scale fertilizer or seed applicators.
(57) What the patent covered
This write-up was generated by AI from the patent's text and may contain mistakes, so check it against the original patent before relying on it.
The independent claim covers a push-type broadcast spreader with two grips on a handle, a hopper with bottom ports, and two rotatable plates beneath the hopper arranged substantially parallel to the ground where one plate rotates clockwise and the other counterclockwise; each hopper port comprises two substantially round holes and one substantially oval hole positioned behind the center of the plates and arranged relative to the plate centerline as recited so that left and right distribution patterns are substantially identical.
Distinguishing feature: Two counter-rotating plates combined with a specific three-hole port geometry (two round holes and one oval hole) positioned behind each plate to balance left/right spread and reduce skewing.
Novelty 3/5. Counter-rotating impellers for symmetry and adjustable hopper ports were a practical improvement on common single-plate rotary spreaders that already used impellers and deflectors.
Manufacturing
Stamped or laser-cut steel impeller plates, injection-molded or roto-molded plastic hopper or pressed metal hopper, bent and welded tubular metal frame, assembly of bearings/axles and handles, final hand assembly of linkage to port controls.
Materials: Sheet metal or stamped steel plates (impellers), Plastic or metal hopper (polyethylene or steel), Steel or aluminum handle/frame, Rubber or plastic grips.
Manufacturability 4/5. Several simple fabricated parts (hopper, two stamped plates, frame) plus bearings and control linkages; requires standard tooling and moderate hand assembly but no electronics.
Market demand
Comparable products are on sale; this exact design was not found. Dual-impeller (two counter-rotating plates) design is available in tow-behind models; a confirmed manual-push dual-impeller model targeted at push operation was not found in current US listings within the scope searched.
- 8620B Tow Behind Spreader with Auto-Stop Dual Impeller · Chapin International
Demand check by web search, week of Oct 12, 2026. Listings change frequently.
Buyers: Groundskeepers, landscapers, small farms, gardeners applying seed or fertilizer.
Sourcing
Factories list related products that could be adapted. This listing shows a dual-impeller (auto-stop dual impeller) tow-behind spreader with a twin-disc design similar in principle to the described product, but configured as a tow-spreader rather than a push-handle manually driven unit.
- Chapin International · https://chapinusa.com · MOQ 1$349.99
Supplier prices are from public listings found by web search, quoted before customization, shipping and duties. Use them to decide whether to request a quotation.
Before manufacturing
No related continuation or divisional patents in force were found. Design patents, trademarks and unrelated patents may still cover the product.
Patent lapsed; practical risks include crowded market of rotary spreaders and possible existing trade-dress or patents on adjustable port controls; description gives specific hole shapes/positions so manufacturing must match those details if relying on the exact method; no legal advice.
This patent has reached the end of its full term and cannot be revived. This page is a research lead, not legal advice. Obtain a freedom-to-operate opinion before manufacturing.