Group 30 - Ryobi Contractor's Saw - Revision history

MAE277G30: /* Parts & Functions */

2007-12-10T18:10:50Z

Parts & Functions

MAE277G30: /* Parts & Functions */

2007-12-10T03:59:32Z

Parts & Functions

MAE277G30: /* Parts & Functions */

2007-12-10T03:58:06Z

Parts & Functions

MAE277G30: /* The Saw Assembly */

2007-12-10T03:56:26Z

The Saw Assembly

MAE277G30: /* The Motor Assembly */

2007-12-10T03:55:45Z

The Motor Assembly

MAE277G30: /* The Motor Assembly */

2007-12-10T03:54:34Z

The Motor Assembly

MAE277G30: /* The Motor Assembly */

2007-12-10T03:53:10Z

The Motor Assembly

MAE277G30: /* The Motor Assembly */

2007-12-10T03:38:50Z

The Motor Assembly

MAE277G30: /* The Motor Assembly */

2007-12-10T03:36:41Z

The Motor Assembly

MAE277G30: /* The Motor Assembly */

2007-12-10T03:35:54Z

The Motor Assembly

@@ Line 175: / Line 175: @@
 '''Bearings and Gears'''
-Previously it was stated that the motor assembly was coupled to the saw assembly via a pinion and cog gear arrangement. As you can see in the image of the rotor gear teeth are machined into the end of the rotor shaft forming a pinion. The gear arrangement produces a single reduction stage stepping the rotation speed of the motor to a safe and effective rotational speed (4600 rpm) for the saw.*
+Previously it was stated that the motor assembly was coupled to the saw assembly via a pinion and cog gear arrangement. As you can see in the image of the rotor gear teeth are machined into the end of the rotor shaft forming a pinion. The gear arrangement produces a single reduction stage stepping down the rotation speed of the motor to a safe and effective rotational speed (4600 rpm) for the saw.The gear ratio is approximately 3.3:1*
 The cog gear appears to be machined from either brass or a brass alloy.

@@ Line 110: / Line 110: @@
-'''
+'''The Stator'''
 The Stator'''
 The purpose of the stator in an A/C motor is to induce a magnetic field. In this case 120V AC current flows through three different copper conductors, 120 degrees out of phase. This creates the instantaneous peak value of the current to spike a different times, yet continuously. The outcome is a rotating magnetic field. We assume that all of the plastic parts on the stator, the brushes and body,  were created using the method of injection molding. An example of the three phase rotating magnetic field principle can been seen at the link below.
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 [[Image:Stator_11 copy.jpg]]
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 |-
 |}
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 The commutator is simply a series of copper plates adhered to a cylinder at the end of the rotor (shown above). As mentioned above the purpose of the commutator is to induce polarity in the armature by generating a DC current. Generator action is achieved through static friction due to relative motion between the brushes and the copper plates. In the image above you can see carbon residue from where the brushes previously rode on the commutator.

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 '''''The Motor Assembly'''''
 '''
 The Stator'''
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 [[http://demonstrations.wolfram.com/ACRotatingMagneticFieldPrinciple/AC Rotating Magnetic Field Principle]](1)
-To manufacture the stator assembly first the central plastic cylinder would have to be made. We concluded through observations that we made that this was done through injection molding. Once the central cylinder was constructed, three individual copper coils were set in place on the cylinder with 14 gauge copper wire. The purpose of this is to create three separate phases for the magnetic field. Then two steel rings were adhered to the inner side and the outer side of the plastic cylinder.
+To manufacture the stator assembly first the central plastic cylinder would have to be made. We concluded through observations that we made that this was done through injection molding. Once the central cylinder was constructed, three individual copper coils were set in place on the cylinder with 14 gauge copper wire. The purpose of this is to create three separate phases for the magnetic
@@ Line 161: / Line 163: @@
 We can assume that this design was used to promote durability, while maintaining a lower cost of assembly. Torx heads on the screws were probably used so the final assembly process could be automated.
 '''''The Saw Assembly'''''
 '''Safety Shrouds'''
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 The arbor size is based on the internal width of these shrouds for where a safe clearance exists for free rotation of the cutting tool.
 '''Bearings and Gears'''
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 The cog gear appears to be machined from either brass or a brass alloy.
 '''Guide Plate'''

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 We can assume that this design was used to promote durability, while maintaining a lower cost of assembly. Torx heads on the screws were probably used so the final assembly process could be automated.
-== The Saw Assembly ==
+'''''The Saw Assembly'''''
 '''Safety Shrouds'''
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 The guide plate is used to maintain the stability of the tool. The operator can set the saw to cut at a certain angle by locking the guide plate into position. By locking it into position, the guide now ensures a clean uniform cut into the surface. The guide plate is equipped with a pointer that the users uses to guide the saw from above. It is set at the front of the guide plate and is used to make sure that the saw is moved in the desired direction.
 ==Technical Drawings & Animations==

@@ Line 107: / Line 107: @@
 == Parts & Functions ==
-== The Motor Assembly ==
+'''''The Motor Assembly'''''
 '''
-''''''The Stator''''''
+The Stator'''
 The purpose of the stator in an A/C motor is to induce a magnetic field. In this case 120V AC current flows through three different copper conductors, 120 degrees out of phase. This creates the instantaneous peak value of the current to spike a different times, yet continuously. The outcome is a rotating magnetic field. We assume that all of the plastic parts on the stator, the brushes and body,  were created using the method of injection molding. An example of the three phase rotating magnetic field principle can been seen at the link below.

← Older revision		Revision as of 03:54, 10 December 2007
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−	'''The Stator'''	+	''''''The Stator''''''

	The purpose of the stator in an A/C motor is to induce a magnetic field. In this case 120V AC current flows through three different copper conductors, 120 degrees out of phase. This creates the instantaneous peak value of the current to spike a different times, yet continuously. The outcome is a rotating magnetic field. We assume that all of the plastic parts on the stator, the brushes and body, were created using the method of injection molding. An example of the three phase rotating magnetic field principle can been seen at the link below.		The purpose of the stator in an A/C motor is to induce a magnetic field. In this case 120V AC current flows through three different copper conductors, 120 degrees out of phase. This creates the instantaneous peak value of the current to spike a different times, yet continuously. The outcome is a rotating magnetic field. We assume that all of the plastic parts on the stator, the brushes and body, were created using the method of injection molding. An example of the three phase rotating magnetic field principle can been seen at the link below.

@@ Line 126: / Line 126: @@
 '''The Rotor'''
-The primary function of the rotor is to create rotational force to drive the saw blade. This is accomplished by inducing a magnetic field in the armature that opposes the rotating magnetic field in the stator. Polarity in the armature is generated by inducing a DC current though relative motion between the copper plates of the commutator and carbon brushes (further discussion below).
+The primary function of the rotor is to create rotational force to drive the saw blade. This is accomplished by inducing a magnetic field in the armature that opposes the rotating magnetic field in the stator. Polarity in the armature is generated by inducing a DC current though generator action in the commutator and carbon brushes (further discussion below).
 Torque is created when the magnetic poles of the armature try to line up with the varying poles of the stator. That torque is transferred directly to the rotor for the saw blade via a pinion and cog gear arrangement. The main shaft or axel of the rotor was made by machining and polishing cold rolled steel in order to insure strength and a uniform composition. A few of the parts on the rotor are plastic which  most likely means that the parts were made by the method of injection molding. We believe that the remaining small intricate metal parts are made from die casting.
@@ Line 149: / Line 149: @@
+The commutator is simply a series of copper plates adhered to a cylinder at the end of the rotor (shown above). As mentioned above the purpose of the commutator is to induce polarity in the armature by generating a DC current. Generator action is achieved through static friction due to relative motion between the brushes and the copper plates. In the image above you can see carbon residue from where the brushes previously rode on the commutator.
-−
-'''The Commutator and Brushes'''

← Older revision		Revision as of 03:38, 10 December 2007
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	\|-		\|-
	\|[[Image:Rotor_1.jpg]]		\|[[Image:Rotor_1.jpg]]
−
−

← Older revision		Revision as of 03:36, 10 December 2007
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	A fan is attached to the axel of the rotor to remove any heat that is generated in the motor. As an auxiliary function the fan also helps to prevent carbon dust from building up on the commutator. We suspect that the fan is created by a combination of both machining and forming due to its shape and slots that must be cut out.		A fan is attached to the axel of the rotor to remove any heat that is generated in the motor. As an auxiliary function the fan also helps to prevent carbon dust from building up on the commutator. We suspect that the fan is created by a combination of both machining and forming due to its shape and slots that must be cut out.
		+

	{\| border="0" cellpadding="2"		{\| border="0" cellpadding="2"

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 |'''Description of the image on the left'''
-<nowiki>-30 Torx driver</nowiki>
+Viewing from the right to the left the first portion on the rotor is the commutator which is electrically coupled to the armature via 14 gauge copper wire. Directly left of the armature is the cooling fan. On the end of the rotor shaft is the pinion.
-−
-<nowiki>-20 Torx driver</nowiki>
-−
-<nowiki>-Ball peen hammer</nowiki>
-−
-<nowiki>-Die</nowiki>
-−
-<nowiki>-3/4 Combination wrench</nowiki>
-−
-<nowiki>-Needle nose pliers</nowiki>
-−