What is a Threaded Bushing?
First off, a threaded bushing is a helical or tapered bushing used to convert between rotational and linear movement or force. It connects threaded pipes and hoses to each other and to caps and fixtures. It is also used as worm gear and similar mechanical connections, used particularly in adjustment mechanisms.
Converting rotary motion to linear motion, for lifting or moving objects, as in a lead screw or screw jack
In all of these applications, the screw thread has two main functions: It converts rotary motion into linear and prevents linear motion without the corresponding rotation.
In most applications, the thread pitch of a screw is chosen so that friction is sufficient to prevent linear motion being converted to rotary, which is so the screw does not slip even when linear force is applied so long as no external rotational force is present. This characteristic is essential to the vast majority of its uses.
Background of Threaded Bushings
Threaded bushings are continuously evolving to keep up with the competitive market today. In the past, the commonly used threaded bushing had some round holes in a lower end or some vertical V-shaped grooves spaced apart equally in an outer surface. The conventional threaded bushing has almost the same diameter in both ends, so it does not tightly engage a hole wherein this bushing is positioned after it is screwed therein.
The second conventional threaded bushing is shaped as a cone with an upper and a lower flat end, comparatively easy to move into a hole of a component, but it may loosen out because of the V-shaped grooves after a long period of use.
The new innovations in threaded bushing in the market today offer a kind of bushing provided with functions to screw into a hole with readiness and to stay therein without possibility of loosening out of the hole.
Latest Threaded Bushing Innovations
A main feature of this product is provision of a lower cone-shaped portion in the body of a threaded bushing and a plurality of triangular recessed stop grooves distanced equally in the lower cone-shaped portion, and each triangular recessed stop groove is defined by a vertical side wall and a curved side wall, engaging uncut wall material of a hole into which the threaded bushing is to be screwed.
A threaded bushing at the present market comprises a cylindrical body provided with a female thread in an inner surface, a male thread on an outer surface, a lower sloping-down portion, and a plurality of triangular recessed stop grooves formed in the lower sloping-down portion spaced in an equal distance. Each triangular recessed groove has a vertical wall and a curved wall forming an angle with the vertical wall.
In using this threaded bushing, the body of the threaded bushing is first placed in a pre-bored round hole in a component, and screwed, with the four curved side walls guiding by cutting in the wall of the round hole of the component and with the vertical side walls cutting the wall of the hole.
Thus, this threaded bushing can quickly screw in the round hole, forcing uncut wall material remain in the recessed groove defined by the vertical wall and the curved wall, and then preventing this threaded bushing from falling off the round hole even after a long period of use.
Advantages and Applications
As can be understood from the above description, this embodiment of a threaded bushing has the following advantages:
1. This threaded bushing can be screwed with easiness into a round hole of a component, by means of the curved side walls as guidance and the vertical wall as a cutting tool to cut the wall of the round hole.
2. The triangular recessed stop grooves can engage wall material of the round hole this threaded bushing is screwed in, holding the bushing tightly, not letting the bushing easily loosen out.
3. This threaded bushing does not produce any small bits of waste or scrap.
Due to the taper (cone) of the thread, when such threads are cut by a tap or a die, increasingly more material is being cut at a time as the length of the thread is increased. Beyond a pipe sizes of a fraction of an inch, it is therefore common to use powered tools when cutting such threads.
The threaded fittings of this bushing are sometimes used on plastic piping. Due to the wedging effect of the tapered thread, extreme care must be used to avoid overstressing the female component of the joint. It is not uncommon for such fittings to split days, weeks, or even years after initial installation, and therefore many municipal plumbing codes restrict the use of threaded plastic pipe fittings.