A rod end bearing, also known as a heim joint (N. America) or rose joint (U.K. and elsewhere), is a mechanical articulating

joint A joint or articulation (or articular surface) is the connection made between bones, ossicles, or other hard structures in the body which link an animal's skeletal system into a functional whole.Saladin, Ken. Anatomy & Physiology. 7th ed. McGraw- ...

. Such joints are used on the ends of control rods, steering links, tie rods, or anywhere a precision articulating joint is required, and where a clevis end (which requires perfect 90-degree alignment between the attached shaft and the second component) is unsuitable. A ball

swivel A swivel is a connection that allows the connected object, such as a gun, chair, swivel caster, or an anchor An anchor is a device, normally made of metal , used to secure a vessel to the bed of a body of water to prevent the craft ...

with an opening through which a bolt or other attaching hardware may pass is pressed into a circular casing with a threaded shaft attached. The threaded portion may be either male or female. The heim joint's advantage is that the ball insert permits the rod or bolt passing through it to be misaligned to a limited degree (an angle other than 90 degrees). A link terminated in two heim joints permits misalignment of their attached shafts (viz., other than 180 degrees).

History

The spherical rod end bearing was developed by

Nazi Germany Nazi Germany (lit. "National Socialist State"), ' (lit. "Nazi State") for short; also ' (lit. "National Socialist Germany") (officially known as the German Reich from 1933 until 1943, and the Greater German Reich from 1943 to 1945) was ...

during

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing ...

. When one of the first German planes to be shot down by the

British British may refer to: Peoples, culture, and language * British people, nationals or natives of the United Kingdom, British Overseas Territories, and Crown Dependencies. ** Britishness, the British identity and common culture * British English, ...

in early 1940 was examined, they found this joint in use in the aircraft's control systems. Following this discovery, the Allied governments gave the '' H.G. Heim Company'' an exclusive

patent A patent is a type of intellectual property that gives its owner the legal right to exclude others from making, using, or selling an invention for a limited period of time in exchange for publishing an enabling disclosure of the invention."A ...

to manufacture these joints in North America, while in the UK the patent passed to '' Rose Bearings Ltd''.Howard, K. 1999. ''Technofile: The rod end bearing''. Motor Sport. LXXV/8 (August 1999), 70-71 The ubiquity of these manufacturers in their respective markets led to the terms ''heim joint'' and ''rose joint'' becoming synonymous with their product. After the patents ran out the common names stuck, although ''rosejoint'' remains a registered trademark of Minebea Mitsumi Inc., successor to Rose Bearings Ltd. Originally used in aircraft, the rod end bearing may be found in cars, trucks, race cars, motorcycles, lawn tractors, boats, industrial machines, go-karts, radio-control helicopters, formula cars, and many more applications.

Female heim joint

Using female heim joints will allow users to make precise changes on key components of fixtures. One example of needing fine adjustment is within the helicopter’s adjustment of the blades. When using the adjustment, it is key to make sure it is in the correct spot or excessive wear will occur. This change allows quick adjustments that are easy with a female heim joint. When dealing with the pitch of a helicopter blades, heim joints are able to be adjusted to 0.010in. If spacing is critical, female heim joints are able to be threaded on, instead of welding inserts to the shaft. When dealing with aluminium shafts, the easiest way to use heim joints is to use the female heim joint. One example is using robots in robotics competitions. Light weight is a key factors when building competitive robots, so using aluminum rods and female heim joints can be key. Another example using female heim joints is the shifter of motorcycles. The shifting mechanism allows forces to be applied linear, but still be able to work at angles when in different gears. Both male and female heim joints require the use of a lock nut after getting adjustment to correct specification needed.

References

{{reflist Linkages (mechanical)

History

Female heim joint

See also

References