Reference no: EM131378906
Figure P15.47 is a schematic representation of a conventional three-speed bicycle hub. Sprocket 1 is driven by the chain. Member 2 always rotates with the sprocket, and slides axially to one of three positions (low, neutral, and high) when the gear shift control is actuated. Sun gear 6 is permanently fixed and serves as the reaction member. Freewheeling pawls 3 (attached to annulus 5) and 9 (attached to arm 8) each represent a set of circumferentially arranged members which function as shown in Figure 15.30b. Light torsion springs hold the pawl tips against the notched inner surface of hub 4 (the member to which the wheel spokes are attached). The pawls permit hub 4 to rotate faster (in the clockwise or forward direction) than the member to which they are attached, but not slower; thus they constitute one-way clutches. The tips of pawls 9 always bear on the inner hub surface, but in low gear sliding member 2 disengages pawls 3 by pushing against them as shown in Figure 15.30b. Operation in the three gears is as follows. Low gear. Member 2 is in position L, where it (1) disengages pawls 3 and (2) drives annulus 5. The output member is the arm, which drives the hub through pawls 9. Neutral gear. Member 2 is in position N, where it continues to drive the annulus but release pawls 3, which drive the hub at sprocket speed. (Pawls 9 remain engaged, but "overrun," causing a "clicking" sound as the pawls go over the notches in the hub). High gear. Member 2 moves out of engagement with the annulus and into engagement with the projecting planet pins, which are part of arm 8. Pawls 3 drive the hub at annulus speed, and pawls 9 "overrun." Now for the problem.
(a) The sun and each of the four planets have a pitch diameter and 25 teeth. How many teeth are in the annulus, and what is the diametral pitch of the gears?
(b) What is the ratio of wheel rpm to sprocket rpm for each of the three speeds? Determine these ratios using at least two of the three methods given in the text.
(c) Explain briefly what happens when the bicycle coasts in any gear.
|
How did greek culture change
: How did Greek culture change as a result of Alexander's conquests? In Plato's description in the Phaedo, Socrates draws the greatest comfort during his hour of death from
|
|
What is the internal rate of return or the irr for project
: The expected cash flows for each year of the five year period is $120,000, $155,000, $186,000, $208,000, and $225,000 for the five years. What is the internal rate of return or the IRR for the project?
|
|
Was a consumer protection law violated
: The used car lot refused to fix the car because the salesperson had written "as is" on the sales slip. Ingram had not been informed that the car was sold to him as is. Was a consumer protection law violated? Explain.
|
|
What you need to learn to present an effective argument
: ENGL 1008 Formal writing - Introduce the issue and then present it in question form - Explain briefly why you are interested in the issue and Describe what you already know about the issue.
|
|
What is the diametral pitch of the gears
: What is the ratio of wheel rpm to sprocket rpm for each of the three speeds? Determine these ratios using at least two of the three methods given in the text.
|
|
Did he succeed in given situation
: Babine sought to recover damages from the manufacturer under the theory of product liability. Did he succeed? Why or why not?
|
|
Did leichtamers recover against manufacturer on a theory
: The manufacturer claimed that the roll bar was provided solely for side-roll protection, not pitchover, as occurred in this case. Did the Leichtamers recover against the manufacturer on a theory of strict liability? Why or why not?
|
|
Examine the evolution of early chinese culture
: Chinese civilization developed over numerous stages. In fact, in the pre dynastic phase, the ancient Chinese grew from small Paleolithic then Neolithic societies. Examine the evolution of early Chinese culture
|
|
What is the circular pitch p
: Sketch each member of the train as a free body in equilibrium (neglect gravity loads).
|