Patents

Hopkin Thomas was not aggressive when it came to patenting the developments he pioneered in this country relative to locomotive design – particularly in regard to suspension systems and the variable draft. The latter made the use of anthracite coal as a locomotive fuel possible. On the contrary, Joseph Harrison, of Garrett & Eastwick (later Eastwick and Harrison) and Ross Winans of the B&O Railroad, who were familiar with Hopkin’s work, took out patents on these innovations. Hopkin was content to see that his developments were utilized and was not particularly interested in protecting these ideas for the financial return that might ensue.

A search of the U. S. Patent Office archives conducted in 2006 revealed that Hopkin Thomas and sons James and William R. held numerous patents. Interestingly a few of the patents held by the sons were in areas that Hopkin pursued – not necessarily areas in which they themselves pursued.

Patents held by Hopkin Thomas

Chilled Wheel-Hub No. 980, October 13, 1838. There are many claims pertaining to the chilling of the cast-iron tire that formed the wearing surface of a rail car wheel – in some of the local histories such claims are attributed to Hopkin Thomas. The only documented claim by Hopkin, however, is this patent which refers to the chilling of the hub, which turns on the axle and which can benefit by improved tolerance to wear achieved by chilling. Note the very low patent serial number – this is an early patent processed by the U. S. Patent Office. This patent was filed when Hopkin was Master Mechanic of the BMRR – before he and van Cleve and others formed their own company to contract with the BMRR.

Coal Breaker No. 3368, December 5, 1843. During the period when Hopkin Thomas was in partnership with A. H. van Cleve, W. R. McKean and Jacob Thomas as a contractor to run the Beaver Meadow mines and railroad, Hopkin developed and used a breaker to reduce the mined coal to “Egg” and “Nut” sizes. These were more profitable commodities than unscreened coal. Coal breakers became landmarks in many of the coal patch towns in northeastern Pennsylvania.

Patents held by James Thomas

Blast Furnace Tops No. 8751, June 10. 1879. This was issued during the period when James Thomas was in Alabama and developing the first coke furnaces in the Birmingham area. It relates to an improvement in the apparatus for opening and closing blast furnace tops.

Hydraulic Motor No. 226133, March 30, 1880. This invention relates to furnishing hydraulic rams which are constructed so that they may be used to deliver power. The invention consists of the combination of a secondary piston and cylinder with the water-chamber of the ram.

Cut-Off Mechanism No. 272,797, February 20, 1883. Cut-off mechanisms were essential to the efficient operation of steam engines. In essence, it allowed the engine to operate efficiently at part power by cutting off the steam to the cylinder during the power stroke so that the expansive nature of steam was utilized. It was only during maximum power operation that the full pressure of the steam needed to be applied to the piston face. This subject had been explored for many years prior to the issuance of this patent to James Thomas. His claim was that the object of the invention was to employ a simple and inexpensive mechanism.

Conduit Systems for Electric Railways No. 544,056, August 6, 1895. Patent issued to James Thomas and William R. Thomas, officials of the Davies and Thomas Foundry of Catasauqua. This invention relates to improvements in conduit systems for electric railways; and it consists of the combination of an underground conduit having conductor-supporting brackets, flat conductors supported by insulators on said brackets, and contacting devices adapted to engage the tops of said flat conductors, said devices being pendent from and connected to the car above the conduit.

Metallic Tunnel No. 558,436, April 14, 1896. Patent issued to James Thomas and William R. Thomas, officials of the Davies and Thomas Foundry of Catasauqua. This invention relates to sectional metallic tunnels; and its object is to facilitate the construction of such tunnels and at the same time produce tunnels of great rigidity, strength, lightness, and durability, and also provide for tightening up the same in case of necessity.

Culvert No. 590,490, Sepetember 21, 1897. Patent issued to James Thomas and William R. Thomas, officials of the Davies and Thomas Foundry of Catasauqua. This invention relates improvements in culverts, and more particularly to that class of culverts which are constructed of metallic sections. Its object is to facilitate the construction of such culverts and at the same time produce culverts of great rigidity, strength, lightness, and reliability; and to this end the invention consists of certain novel constructions, combinations, and arrangement of parts.

Insulator for Use on Electric Railways No. 644,646, March 6, 1900. Patent issued to James Thomas and William R. Thomas, officials of the Davies and Thomas Foundry of Catasauqua. This invention relates to improvements in insulators, and particularly to that class of insulators which are adapted for use upon electric railways. It consists of a device for insulating a conductor comprising a base, an insulating-block having a recess adapted to fit upon a projecting portion of the said base, and a conductor supporting cup fitting upon and inclosing the other portion of the said block, means for securing the parts together, and means for holding the conductor in position upon the said cup.

Mandrel No. 662,835, November 27, 1900. Patent issued to James Thomas and William R. Thomas, officials of the Davies and Thomas Foundry of Catasauqua. This invention relates .to improvements in mandrels, and particularly to the class of mandrels which are capable of expansion. The object of the invention is to provide an improved mandrel of simple and economic construction, which shall be easy to operate and not liable to breakage or undue wear by ordinary usage.

Milling-Chuck No. 774,616, November 8, 1904. Patent issued to James Thomas and William R. Thomas, officials of the Davies and Thomas Foundry of Catasauqua. This invention relates .to improvements in supports, and particularly to chueking-heads for supporting articles during a machining operation.

Patents held by W. R. Thomas

Blasting Powder. No. 32016, April 9, 1861. It is known that the back wall of W. R. Thomas’ kitchen was blown out while he was experimenting with various compositions, which were alternatives to black powder. Local histories refer to his work on dynamite, however, dynamite was a stable form of TNT patented by Alfred Nobel – blasting powder, a simple and inexpensive explosive used in mining operations, is the more accurate term.

Locomotive Firebox – Steam Boiler Furnace. No. 23,278 March 15, 1859. This patent was filed at the time when William Thomas was at the Crane Iron Co. with his father. The Crane may have had an interest in locomotive construction as it was using locomotives in conjunction with the operations of the C&F R. R. The stated objective of this invention was a firebox construction that facilitated repairs.

Annealing Furnace. No. 73,407, January 14, 1868. This patent was filed shortly after William joined the McKee-Fuller & Co, Car Wheel & Axle works. It deals with an improvement to furnaces used in the annealing of railroad car wheels.

Improvement in Steam-Engine Piston-Valves No. 76,062, March 24, 1868. Patent issued to William R. Thomas and Thomas Evans of the McKee-Fuller Co. of Catasauqua. This invention relates to a new construction of steam-engine valves.

Improved Car Wheel. No. 79,029 June 16, 1868. Like his father, William had an interest in the manner in which railroad car wheels were constructed. This patent concerns the fabrication of the molds used in casting the wheels – the claim is that the distortions caused during the heating and cooling cycles are diminished.

Improved Car Wheel. No. 93769, Aug 17, 1869. This patent deals with the construction of the car wheel (as opposed to the mold used in casting it – see above).

Improved Slide Valve Gears No. 119,590, October 3, 1871. Patent issued to William R. Thomas, Thomas E. Evans and Joshua Hunt of the Crane Iron Works in Catasauqua. This invention relates to improvements in valve gears used in pumping engines.

Magnetic Ore-Separator No. 403,624, May 21, 1889. Patent issued to William R. Thomas of Catasauqua. This invention relates to improvements leading to more effective use of said separators.

Method of Mixing Alloys No. 487,338, December 6, 1892. Patent issued to William R. Thomas of Catasauqua. This invention relates to the art of working metals, and has its object certain improvements in the method or process of mixing alloys, whereby their density is increased and the grain of the metal rendered more regular than under the previous practice.

Valve No. 927,438, January 12, 1909. Patent issued to William R. Thomas of the Davies and Thomas Foundry of Catasauqua. This invention relates to valves adapted to direct the flow of liquid in any number of different ways.

Improved Valve Mechanism for Internal Combustion Engines No. 1,063,082 May 27, 1913. Patent issued to William R. Thomas and William R. Thomas, Jr of the Davies and Thomas Foundry in Catasauqua. This invention relates to improvements in valve mechanisms for internal combustion engines and provides an extremely simple and economical construction which will provide ample port area for quick inlet and exhaust valves.

Patents Held by Hopkin Thomas

Friction Clutch No. 1,110,972, September 15, 1914. Patent issued to Hopkin Thomas of the Davies and Thomas Foundry of Catasauqua, son of William R. Thomas and grandson of Hopkin Thomas. This invention relates to friction clutches and the object of the invention is to provide improved means for throwing the driven mechanism into engagement with the driving mechanism.

Patents awarded to Others

Ross Winans

Ross Winans of the B & O Railroad was a prolific filer of patents – both with respect to his own innovations and with respect to variants of innovations of others in the field of steam engine locomotion. Winans was well aware of Thomas’ activities and the two surely had direct interactions during the period when Thomas was reviewing locomotives for purchase by the BMRR. The following patents relate to topics of interest to both men.

Variable Exhaust No. 5056, April 10, 1847. Use of a variable exhaust draft was the key to the utilization of anthracite coal in steam locomotives. Anthracite required a strong induced draft in order to burn. During periods of heavy loads, the draft induced by the exhaust steam ejecting into the exhaust pipe had to be maximized. During periods when the engine was standing by, a weak but constant draft was required. To accommodate these requirements, Hopkin Thomas utilized a lever that would change the position of the steam exhaust jet as it entered the throat of the exhaust pipe. By this device, the locomotive engineer could regulate the exhaust. This accomplishment was noted in the BMRR Minutes Notes recorded in January of 1839. A narrative account of the efforts of Thomas and his collaborator and fireman, Thomas Evans, related to burning anthracite is given in the testimonial published at the time of Hopkin’s death. Also of interest is Evan’s account of Winan’s visit to Evans when the latter was Master Mechanic of the Hazleton R. R. Winans is quoted as saying that he did not come “as a snake in the grass”, but he did spend the better part of a day learning how Thomas had achieved a practical variable draft. In this patent of 1847, Winans alludes (Line 75) to a prior patent held by him on the variable exhaust, however a copy of that patent has yet to be located – presumably the date of that patent would be in the early 1840’s. This 1847 patents relates to improvements upon that earlier patent.

Other Patents on Variable Exhaust – 1834 – 1860.

Andrew Eastwick, Draft Box, No. 674 April 5, 1838.

William M. Hurlbert, Variable Exhaust, No. 25,509, September 30, 1850.

Charles F. Thomas, Means for Increasing Draft, No. 13,258, July 10, 1855.

Samuel L. Hay, Variable Exhaust, No. 13,648, October 9, 1855.

Ross Winans, Improved Blast Pipe, No. 22,597, January 11, 1859.

Thomas B. Quigley, Exhaust Regulator, No. 24,661, July 5, 1859.

George Edwards, Variable Exhaust Pipe, No. 27020, January 31, 1860.

Richard McDowell, Improved Variable Exhaust, No. 39,583, August 18, 1863.

Return to the Table of Contents

About The Hopkin Thomas Project

Rev. July 2016