History of Torque Wrenches

Torque wrenches are tools designed for applications that require a specific amount of torque in tightening nuts or bolts. Different types of torque wrenches have different ways of telling you that you have reached the right amount of torque. But before knowing the nitty-gritty of this particular hand tool, let’s first dive through the history of torque wrenches.  You can also refer to the  following link to find a list of torque wrench reviews. If you’re looking for high-quality, signature hand tools, you can check them online.

Patent Applications

It was said that John H. Sharp was the first person who applied for a patent in May 18, 1931. His patent was referred to as a torque-measuring wrench. It was described as “relates to wrenches, and more particularly to one for indicating the amount of force.” Such patent was granted and published on July 9, 1935.

However, there are other articles claiming that it was actually Conrad Bahr who invented the torque wrench back in 1918. This claim states that Conrad designed such torque wrench when he was working for the New York City Water Department. The tool was intended to avoid over-tightening of bolts on water main and steam pipes.

Together with Bahr’s partner, George Pfefferle, the adjustable ratcheting torque wrench was designed and patented in 1935. Pfefferle was then an engineer for S.R. Dresser Manufacturing Co. The two designed a tool that’s equipped with audible feedback and back-ratcheting movement restriction once the required torque was reached.

Continuous Development

Torque wrenches are quite simple and easy-to-use tools. It shouldn’t be surprising that there’s really not much to know about the history of torque wrenches. What’s interesting to note is that the designs from patents were further developed to make them useful for various applications. As a result, there are now many different types of torque wrenches available in the market.

Introduction of Different Types of Torque Wrenches

The beam-type torque wrenches, for one, is said to be developed around late 1920s to early 1930s. Walter Percy Chrysler was then working for Chrysler Corporation when he designed the tool. Such invention was patented in 1938 under the name of Paul Allen Sturtevant.

Sturtevant was then a sales representative for Cedar Rapids Engineering Company and was granted by Chrysler the license to manufacture the beam-type torque wrenches. He was also considered the first person to sell torque wrenches.

From the above-mentioned invention, the dual-signal deflecting beam torque wrench was later developed. It was patented in 1948 by an Australian company named Warren and Brown.  The said invention applies torque to a deflecting beam instead of a coil spring. As a result, the wrench is more accurate and has longer working life.

The more advanced electronic torque wrench equipped with angle measurement was filed for patent in 1995. It was the company named Saltus-Werk Max Forst GmbH that applied for said invention.

Closing Words

What we’ve shared here are just few of the notable torque wrench developments and patents. Yet, certainly there are other types of torque wrenches that have been developed and were not included here. Regardless of whether they are patented or not, we hope that you will appreciate how a simple hand tool was improved through the years. This history of torque wrenches just gave you an idea of how different principles were applied to design the different types of this hand tool.