# Josephine Cochrane's Mechanical Dishwashing Machine

> A late 19th-century invention that used a pressurized water pump and a rotating rack to clean dishes mechanically, moving away from manual scrubbing.

- **Patent:** US 355139
- **Original title:** Dish-washing machine
- **Owner:** Josephine G. Cochrane
- **Granted:** 1886
- **Status:** Active
- **Times cited:** 2
- **Field:** mechanical, consumer_electronics

## What it does

The device uses a motor-driven pump to force hot, soapy water upward through a central pipe onto a wire rack holding the dishes. The rack is designed to rotate, ensuring that the pressurized water reaches every surface of the plates and cups. By containing the water within a sealed chamber, the machine automates the process of removing food residue, which was previously done entirely by hand.

## What it does NOT cover

- Does not cover modern electronic sensors or automated detergent dispensers.
- Does not cover the use of ultrasonic waves or high-pressure steam cleaning.
- Does not cover internal heating elements for drying cycles.
- Does not cover the modern 'under-the-counter' form factor common in residential kitchens.

## The clever bit

The innovation was the use of water pressure combined with a specific rack design to ensure water reached all surfaces, rather than just relying on mechanical scrubbing brushes.

## Real-world examples

1. Early mechanical dishwashers used in hotels and large households in the 1890s.

## Why it matters

This patent represents one of the first successful attempts to commercialize mechanical dishwashing. It shifted domestic labor expectations and eventually led to the creation of the company that became KitchenAid, fundamentally changing the appliance industry.

## Frequently asked questions

### What does Josephine Cochrane's Mechanical Dishwashing Machine cover?

A late 19th-century invention that used a pressurized water pump and a rotating rack to clean dishes mechanically, moving away from manual scrubbing.

### Who owns patent US 355139?

Josephine G. Cochrane owns this patent, granted in 1886.

### When does this patent expire?

This patent has expired and is now in the public domain — anyone can use the invention freely.

### What is patent US 355139 cited by?

This patent has been cited by 2 later patents that build on its ideas.

### What problem does this patent solve?

This patent represents one of the first successful attempts to commercialize mechanical dishwashing. It shifted domestic labor expectations and eventually led to the creation of the company that became KitchenAid, fundamentally changing the appliance industry.

### What does this patent NOT cover?

Does not cover modern electronic sensors or automated detergent dispensers.

**Full plain-English explainer:** https://patentbrief.org/patent/us/355139/dishwasher-cochrane

**Original patent:** https://patents.google.com/patent/US355139

---

_Source: PatentBrief — https://patentbrief.org. Patent facts are from public records; the plain-English explanation is PatentBrief's._


## Related patents

Semantically similar inventions in the PatentBrief corpus:

- [How the First Modern Kitchen Garbage Disposal Was Invented](https://patentbrief.org/patent/us/2012680/garbage-disposal-hammes) — John W. Hammes' 1933 invention of a motorized grinding device that mounts under a kitchen sink to pulverize food waste into small particles for disposal through plumbing.
- [How Early Washing Machines Moved Clothes](https://patentbrief.org/patent/us/966677/electric-washing-machine-fisher) — This 1910 patent describes a mechanical system designed to power the washing action within early washing machines, focusing on how the tub or agitator moved.
- [How the 1940 Nachumsohn Cooking Apparatus Works](https://patentbrief.org/patent/us/2187888/crock-pot-slow-cooker-naxon) — A 1940 patent for a cooking device designed to heat food efficiently using an enclosed chamber and specific heat distribution methods.
- [How the Modern Disposable Paper Cup Was Invented](https://patentbrief.org/patent/us/1032557/dixie-cup-disposable-paper-cup) — A 1908 patent for a sanitary, single-use paper cup designed to prevent the spread of germs from shared public drinking vessels.
- [How Mary Anderson Invented the Windshield Wiper](https://patentbrief.org/patent/us/743801/windshield-wiper-anderson) — A 1903 invention by Mary Anderson that allowed drivers to manually clear rain and snow from their windshields using a lever inside the vehicle.