Couplings, Clutches And Brakes Flashcards
This coupling is used in low speeds and low torque applications ,also they have keyway in the bore and sort screws tighten the coupling on the shaft , what type of coupling is this ?
Sleeve couplings
These couplings grip the shaft by using tapered sleeves in tapered hubs , these couplings are used on equipment with light moderate loads
Compression couplings
These couplings have two halves bored or keyed to fit in the shafts , the flanges may also be mounted to the shaft by heavy interference fit or taper fit
What coupling is this
Flange face couplings
This coupling have two sprockets keyed to shafts connected connected with chain
What is this coupling called ?
Roller chain coupling
This coupling is recommended for heavy - duty drives up to 5000 rpm , this coupling also runs quietly
Silent chain coupling
This coupling operates quietly and smoothly and often used for light power transmission drives
Which coupling is this
Synthetic chain coupling
This coupling uses a flexible element , which is molded into a shape like a tire
Rubber tire coupling
This coupling transfer torque through and elastomeric element , the rubber that is used is bonded to metal inserts that bolt to the hubs
Elastomeric couplings
This coupling uses rubber or neoprene biscuit molded to steel sleeves , these biscuit allow considerable deflection , torsional flexibilty ,axial float during operation
Pin and biscuit coupling
What’s a major advantage of a rubber tire coupling ?
Is that the driving element case be changed by simply loosening of the side flange bolts
This coupling uses a series of thin plates to form a flexible steel disc
Flexible metal disc coupling
If single set of disc is used for a metal disc coupling only tolerate angular misalignment this true or false ?
True
Two of sets of disc for a flexible disc coupling are used produce what more angular and offset , true of false ?
True
This coupling has two hubs with slotted flanges , what coupling is this ?
Steel grid couplings
This coupling consists of two metal hubs , which have three machined or cast jaw sections with the spider , what is the name of this coupling
Jaw and spider
This coupling consists of pairs of cast iron or steel flanged hubs , these hubs are also not recommend on drives where excessive misalignment is likely to occur
Pin and rubber bushing coupling
This is is coupling is used between the driver and the driven
Double Universal joint
This coupling consists of two operating members , the Impeller sometimes referred to as a pump and the turbine , which can also be called a runner , what coupling is this
Fluid coupling
This coupling uses mechanical contact between the friction shoes and the drum , but application is by , what is the called ?
Centrifugal shoe coupling
These clutches are usually engaged by mechanaily shifting levers and this clutch can be engaged at very low speeds , but can disengaged as long as it’s not making high tourque.
. Power transfer is jaw to jaw contact
. Accusation method is mechanical sliding one jaw by a lever , electric Solenoid , pneumatic cylinder or hydraulic cylinder
Square jaw a clutches
The clutch can be engaged at higher speeds than the square jaw
Spiral jaw clutches
This clutch can be activated mechanically or electrically ,one hub of the clutch must be free to slide on a key or spline to allow for engagement
.power transfer is tooth to tooth contact
. Actuation method is most often by electric solenoid
Multiple tooth clutches
Uses a activated magnetic field that pulls a moveable armature with friction disc mounted on its face
Electromagnetically activated
This cluch uses wedging power , the smaller the angle the greater the wedging power
Cone clutches
If the load on the output exceeds the strength the clutch slips , they are used for light high speed applications
Hysteresis
These clutches consist of two drums running very close to each other , similar to hysteriss clutches expect have soft iron rotors
Eddy current clutches
These are used in extremely low power applications and moderate large torque loads , the more wraps on the spring the greater the power it can transmit
Wrap - spring clutches
This coupling need no lubrication. In this type of coupling, a flat centre member is connected between metallic disks which are bolted to the hubs.This is a double-engagement coupling. The transinission of power is from hub to disk to centre member to other disk to other hub.
This coupling allow highspeed operation and are well balanced.
Torsional characteristics are very stiff and allow this coupling to be used where no backlash is permitted.
Metallic disk couplings
This coupling transmits the torque
between the driver and the pump adequately if the shafts rotate in the direction of the
thread of the coupling.
Threaded coupling
are used in heavy load and torque services. The two halves of the
coupling are split parallel to the shafts’ axes and have machined keyways in both shafts.
They can be made of steel or cast iron. Over-tightening the cast iron couplings can lead to
Ribbed couplings
These couplings are not recommended on drives where excessive misalignment is likely to occur. Misalignment causes the bushings to wear quickly, and an increase in vibration may result. This coupling works well on reversing drives and can compensate for some axial end float between the machine’s shafts.
Pin and rubber bushing coupling
are used to connect shafts that intersect at angles greater than can be accommodated by flexible couplings. If the alignment is too accurate the needles in the joint do not rotate. This may cause false brinelling and lubrication problems. There are many applications for universal joints in industrial applications. The three types of universal joints are: single, double, and constant velocity.
Single Universal joint
are used where the joint angles are unequal (Figure 33) or when a single CV joint is used and constant velocity output is required. They produce a very even and smooth transfer of power with no fluctuations in speed. These can be made in several ways.
Cv joints
BThe impeller (pump) has a series of radial blades. The turbine (runner) is the output member and consists of a series of radial blades. The impeller and the turbine blades face each other (Figure 37).
Fluid coupling
Thus coupling usees a mechanical contact between the ———
and the drum, but application is by centrifugal force. The coupling
allows the prime mover to reach partial speed before the load is fully engaged. This is
useful on drives with frequent stops and starts under heavy loads.
couplings are equipped with springs that determine engagement chara
Centrifugal shoe coughing
sleeve couplings, roller chain couplings, rubber tire couplings, steel grid couplings,
jaw and spider couplings and splined rubber couplings.
Low hp couplings