Washer-Grover is a simple solution to a complex problem

Washers are called fasteners made of various materials, mainly metal or plastic. Their form is often circular, but sometimes there is another (square, rectangular and even polygonal). They are designed for load distribution when screwing nuts, screws, screws, bolts, studs and other threaded connections, to prevent dents and other damage, and to ensure good electrical contact.

But there is an unusual puck. Grover has a special purpose.

The technical problem and its solution

The rapid development of machine building, which occurred in the second half of the XIX century, revealed a significant shortage of threaded connections. Mechanical loads, vibration and various vibrations of the moving parts of the machine nodes caused, in addition to fatigue failure, the risk of spontaneous reduction in the strength of their joints. Nuts and bolts loosened, and in order to control their condition, effort and time were required. At the same time, riveted joints, which were an alternative to threaded ones, made it more difficult to dismantle, and consequently also to maintain technical equipment, which became increasingly difficult. The special washer-Grover was the solution to this problem.

Principle of operation

All ingenious is arranged simply, and works faultlessly. Washer-Grover is a single coil spring or ring with a slot, slightly curved so that the gap diverges in a direction that prevents rotation of the nut when it is unscrewed. During a straight run, nothing prevents the movement of the fastening assembly consisting of a bolt (screw or hairpin) and a nut. But when you try to rotate it in the opposite direction, the sharp edge digs into the metal and makes it difficult.

Where did the name "Grover" come from?

There are two main versions of why the spring washer is so called. According to the first, the name of the inventor was immortalized. In favor of this assumption is the fact that right up to the beginning of the fifties the word "Grover" in the Soviet technical documentation was written with a capital letter. After the campaign against foreign words began in the USSR, in the opinion of the then linguists who only littered the "great and mighty", transistors were called triodes, resistors were resistances, and the puck was changed to spring, or at least recommended to write this The term with a small letter.

The second variant of the origin of the term is based on its alleged kinship with the English word "Grow", meaning "growth". If you think figuratively, then the stronger the clamping junction is clamped, the more the spring washer, because of its spring nature, resists. And when unscrewing, it straightens, and its maximum transverse dimension increases, that is, it grows.

All fasteners produced in our country are strictly standardized. Is not an exception and washer-Grover. GOST 6402-70 clearly regulates the mechanical properties of "spring washers", the materials from which they are made, and the geometric dimensions by which they are performed. This is not surprising, from this, at first glance, a secondary assembly unit can depend on the safety of operation of a complex machine.