Disengaging clutch

Safety clutches usually consist of two parts the actual safety clutch and the elastic part, both of which soften vibrations and shocks and equalize any misalignment between motor and gearbox. Essentially, a distinction is made between slip clutches and mechanically disengaging clutches. Despite their higher cost, pneumatic slip clutches are normally used on larger extruders, because they are easy to handle, which means shorter downtimes in case of overload. 

Figure 17.20 Cross-section of mechanically disengaging clutch...

Drive jams Failure to separate halves High Clutch disengages with drive power. 

Wlien the driver disengages the clutch by pushing down on the clutch pedal, a lever system (not shown) moves the pressure plate to the right against compres-... 

Clutches are designed to transmit intermittent power to a driven unit. Unlike a normal coupling, which maintains constant power transmission between the driver and the driven unit, a clutch is designed to alternately engage and disengage. When engaged, the clutch transmits full torsional power to the driven unit. When disengaged, the clutch disconnects the driver from the driven unit. 

Many machine systems require clutches, devices that engage and disengage a driven unit from its rotating power... 

A clutch acts like an on-demand spacer coupling. In the disengaged position there is space between the two shafts. When the clutch is engaged, the mechanism hlls the void to reconnect the shaft. 

One-way A one-way or flywheel clutch is a device that transmits torque in one direction, but disengages in the opposite direction. The typical design of flywheel clutches incorporates a tooth profile that engages in one direction only. If rotation of the drive shaft is reversed, the drive hub will freewheel and cannot engage the driven hub. 

The primary advantage of friction clutches is their ability to minimize engaging torque. Figure 59.22 shows an example of this type of clutch, which transmits torsional power from a driver to a driven unit as a result of friction between two or more mating parts. By relying on friction to transmit power, the transition from disengaged... 

D. The uncoupling of ATP formation from electron flow is analogous to disengaging a clutch, which allows a motor to run faster the O2 evolution therefore initially speeds up. After awhile, the lack of ATP formation causes no CO2 to be fixed the electron acceptors therefore stay reduced and electron flow to them is curtailed. Moreover, electron flow may eventually switch over to the pseudocyclic type, which involves no net O2 evolution. 

Synchro-Self-Shifting ( SSS ) Clutches The automatic freewheel action of an SSS clutch simplifies plant startup and shutdown sequences. It is, of course, receiving its power input from a gas turbine or similar driver, while its output is connected to a driven machine. The drive disengages automatically when the driven machine speed exceeds that of the driver. Since large gas turbines are usually brought up to speed with either a startup gear motor or a helper turbine, thousands of SSS clutches (Fig. 29-77) are finding application here. 

When the main clutch teeth (E) are fully engaged, power is transmitted from the turbine to the generator. Engagement and disengagement of the main clutch is cushioned by the oil dashpot (H). 

The re-filling time is longer than with pneumatic pumps it takes one to several minutes, depending on the chamber volume and whether the chamber must be rinsed or not when a new solvent is used. To re-fill the chamber, the piston must be retracted. This operation can be effected manually with a crank after disengaging the motor-piston clutch, or can be made with a second, more powerful, motor actuated by a switch (Perkin-Elmer Model 601). Depression of the Fill push-button switch of the Varian Model 8500 pump actuates the downward piston movement and, at the same time, pressurizes the solvent reservoir, allowing the chamber to be re-filled. In the ISCO Model Sl l pump, the suction created by the retraction of the piston pennits re-filling from a reservoir. 

Owing to the eccentric positions of the lead-filled hole and the open hole, considerable force is needed to hold the radiation door in certain positions. A special anti-kickback clutch is provided to make it inposaible for the door to move unless driven or allowed to turn by rotation of the external drive.shaft. The design is "fail safe" in case the drive becomes disengaged. When the bean hole components are removed, care must be taken that the.radiation door- is in a "free down" position so that the end-position locating pin will not be sheared when thie removable shield is withdrawn. Associated with the radiation door is its position indicator, this is mounted on the face of the reactor over the cubicle to indicate the actual door position. 

The flywheel is connected to a crankshaft through a clutch which can be set for continuous or single stroking. In the single-stroke mode, the clutch is automatically disengaged at the end of each stroke and the press will not restart until activated by the operator. A connecting rod is attached at one end to the crankshaft and at its other end to the slide. 

If the free stroke of clutch pedal and clearance between the clutch pedal and floor when the clutch is disengaged dc not consist with the standard, this may by caused by the air in hydraulic system and failure of main cylinder or clutch. It can discharge the air of system or dissemble and inspect the main cylinder or clutch. 

Disengagement of transmission The clutch guide bearing is worn. Replace the guide bearing... 

The torque converter clutch control valve (refer to Figure 3.20) has two kinds of position status it engages or disengages the torque converter. 

When the valve is in closed or release position, the oil from the primary regulating valve enters into the disengagement side of torque converter clutch. After through the torque converter, the transmission fluid returns to the torque converter clutch control valve, finally enters into the oil cooler directly. 

Control growth came about primarily with the advent of the friction clutch. Introduction of the friction clutch created the necessity to engage the clutch or disengage the clutch at any point in the stroke—obviously, the major advantage of the air clutch. Previously, a mechanical clutch once engaged did not disengage until the stroke was completed or a disaster crash took place. 

Stmctural changes such as the engagement and disengagement of a clutch or the change between slip and stick mode for two rigid bodies considered as instantaneous... 

As an example, consider the bond graph of a clutch in Fig. 2.15. There are no causal paths between resistors and no dependent storage elements. Clearly, as long as the clutch is disengaged, the DAE system is of index 0. In the case when the clutch is engaged, the unknown constraint force M between the two plates keeps their inertia elements in integral causality and at the same time ensures that the algebraic constraint... 

In some way, this coupling of two models by residual sinks may be compared to the temporary coupling of two bodies such as the plates of a clutch by a residual sink (cf. Fig. 2.15). As long as the clutch is disengaged, there is no force acting between the two plates. If, however, the clutch engages, a torque acts on both of them such that the difference of their angular velocities is zero. The load side is forced to adapt to drive side. This approach has been applied for the numerical computation of ARR residuals from continuous time models [14, 17] and recently also to systems described by a hybrid model [18]. 

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