# U.S. Patent 2,134,582 — Royle, "Loading Machine" (EIMCO)

**Type:** source
**Status:** Useful
**Confidence:** High
**Source Type:** patent
**Publisher:** U.S. Patent and Trademark Office
**Retrieved:** 2026-08-12
**URL:** https://image-ppubs.uspto.gov/dirsearch-public/print/downloadPdf/2134582
**Updated:** 2026-08-11

## Summary

The first patent behind the EIMCO rocker shovel loader: Edwin B. Royle's 1937 application for a mine "loading machine or mucker", assigned to The Eimco Corporation of Salt Lake City. It is the document that ties the machine, the inventor, and the Salt Lake City manufacturer together in one dated public instrument, and it names the earlier Finlay patents it improves on.

## Useful Claims

- Patent number 2,134,582, titled "Loading Machine". Application serial no. 145,291, filed May 28, 1937; granted October 25, 1938.
- The face of the patent records the inventor as Edwin B. Royle of Salt Lake City, Utah, "assignor to The Eimco Corporation, Salt Lake City, Utah". Both the inventor and the assignee are recorded as Salt Lake City — the Utah claim on this machine is on the patent itself, not only on the ASME plaque.
- The invention is described as improvements in "loading machines or muckers of the type employing a vertically swinging shovel, which is also oscillatable horizontally on a vertical axis in order that digging or loading operations of the shovel may be accomplished laterally of the machine."
- What this patent specifically adds is the side-cleanup problem: it is "particularly related to the means for centering the loaded shovel or dipper, after a lateral digging operation, in order that the shovel may be alined with a car when the loaded shovel is in dumping position." The claimed mechanism is a cam-and-drum arrangement on the superstructure that recenters it and holds it centered through the dump.
- The specification states that this invention "is an improvement on the appliances illustrated in patents of Finlay et al. Nos. 1,906,000 and 1,906,001 of April 25, 1933" — the documentary link from Royle's EIMCO work back to the earlier Royle–Finlay overshot loader.

## Reliability Notes

Primary tier. A granted U.S. patent is a dated public instrument the USPTO must keep, retrievable forever by number, so no archive snapshot is owed. The URL is the issuing body's own PDF of the grant.

Scope. This patent establishes the inventor, the assignee, both Utah addresses, the dates, and the mechanism it claims. It does not establish the Model 12B designation, the 1938 product introduction, unit sales, the international licensing list, or the ASME landmark designation — those rest on the ASME and ETHW records the fact page cites separately, and the ~29,000-unit figure remains uncarried by any primary document.

The OCR of the 1938 grant renders the inventor's surname as "Boyle" in the printed header; the USPTO's own inventor field for this patent reads Royle, as does every secondary account, and the misreading is an artifact of the scan rather than a discrepancy in the record.

## Related Pages

- [EIMCO Rocker Shovel Loader](eimco-rocker-shovel-loader.md)