Showing posts with label double universal joint. Show all posts
Showing posts with label double universal joint. Show all posts

Monday, August 11, 2014

Double Cardan Shaft

Double Cardan Shaft

A configuration known as a double Cardan joint drive shaft partially overcomes the problem of jerky rotation. This configuration uses two U-joints joined by an intermediate shaft, with the second U-joint phased in relation to the first U-joint to cancel the changing angular velocity. In this configuration, the angular velocity of the driven shaft will match that of the driving shaft, provided that both the driving shaft and the driven shaft are at equal angles with respect to the intermediate shaft (but not necessarily in the same plane) and that the two universal joints are 90 degrees out of phase. This assembly is commonly employed in rear wheel drive vehicles, where it is known as a drive shaft or propeller (prop) shaft.
Even when the driving and driven shafts are at equal angles with respect to the intermediate shaft, if these angles are greater than zero, oscillating moments are applied to the three shafts as they rotate. These tend to bend them in a direction perpendicular to the common plane of the shafts. This applies forces to the support bearings and can cause "launch shudder" in rear wheel drive vehicles.[13] The intermediate shaft will also have a sinusoidal component to its angular velocity, which contributes to vibration and stresses.
Mathematically, this can be shown as follows: If \gamma_1\, and \gamma_2\, are the angles for the input and output of the universal joint connecting the drive and the intermediate shafts respectively, and \gamma_3\, and \gamma_4\, are the angles for the input and output of the universal joint connecting the intermediate and the output shafts respectively, and each pair are at angle \beta\, with respect to each other, then:
\tan\gamma_2=\cos\beta\,\tan\gamma_1\qquad\tan\gamma_4=\cos\beta\,\tan\gamma_3
If the second universal joint is rotated 90 degrees with respect to the first, then \gamma_3=\gamma_2+\pi/2. Using the fact that \tan(\gamma+\pi/2)=1/\tan\gamma yields:
\tan\gamma_4=\cos\beta/\tan\gamma_2=1/\tan\gamma_1=\tan(\gamma_1+\pi/2)\,
and it is seen that the output drive is just 90 degrees out of phase with the input shaft, yielding a constant-velocity drive.

Sunday, July 13, 2014

Universal joints


universal jointuniversal couplingU-jointCardan jointHardy-Spicer joint, or Hooke's joint is a joint or coupling in a rigid rod that allows the rod to 'bend' in any direction, and is commonly used in shafts that transmit rotary motion. It consists of a pair of hinges located close together, oriented at 90° to each other, connected by a cross shaft.



Universal Joint Shaft Assembly

Timothy Holding Co.,Ltd. manufacture SWF Series,SWC Series and SWP Series universal joint shafts for more than 20 years.
Our focus on technical innovation, quality performance, reliability and flexibility has made Timothy Holding Co.,Ltd. the global leader in industrial assemblies and universal joint shafts. As we continue to innovate, we will not only provide customers with the same quality and support they have come to expect, but we will also consistently surpass those expectations. Because of our constant dedication to improvement, the replacement cardan shaft assemblies will meet and can even exceed the quality of the parts customers are replacing .

Our universal joint shafts are largely used in below areas:

1.Rolling mill plants
2.Paper machines
3.Steel mills
4.Hydraulic fracturing operation
5.Crane systems
6.Marine drives
7.Power station equipments
8.Heavy-loaded plants of general machinery construction
9.Mining machinery
10.Rubber machinery
11.General machinery construction plants
12.Cement industry

http://www.timothyholding.com