Antoine
Taesik
Carissa
Table of contents
Assembly drawingp.3
Exploded viewp.4
Bill of Materialsp.5
Description of each partp.6
List of matesp.8
Drawings & pictures of parts andp.10
subassemblies
We purchased a battery-operated quartz analog alarm-clock for $13 at the Coop. It is manufactured by Westclox in China (that is what the back casing says). The instruction manual mentions the following address in the United States, as well as a fax number in the same state:
General Time Service Center
120 Newton Bridge Road
Athens, Georgia, USA 30607-1163.
We disassembled the clock into several different parts listed below in the order of disassembly. We had to break two wires connecting a coil to a printed circuit board (PCB1), but nothing else was broken, so that we were able to reassemble the clock entirely. The smaller parts (gears) were marked with a pen so as to remember where they go and which side up.
3 casing screws
Battery cover (dark gray plastic)
Back casing (dark gray plastic)
Top alarm button (shiny gray plastic)
On/off alarm button (gray plastic)
Setting knob (black plastic)
Clock cover (transparent plastic – clipped)
2 thinner screws attaching the spring slide to the gear box subsystem
Spring slide (black), linked by a wire
2 shorter screws attaching the bell subsystem
Bell subsystem (metal, black plastic, motor), linked by two wires
Second hand (shiny gray)
Minute hand (black with fluorescent sticker)
Hour hand (black with fluorescent sticker)
Alarm hand (gray)
Gear box subsystem (see below)
1 gray flex cable linking the gear box subsystem to a small circuit board
Small circuit board (PCB 2) (just for connecting wires – soldering)
Gear box subsystem
Gear box cover (clipped, with sliding switch on top)
1 gear T with metal axis and three slots (T for top, inscription on top)
1 gear (white) FL (far left if coil to the right, inscription on top)
1 gray gear L (left if coil to the right, inscription on top)
1 tiny gear B (bottom, under the coil) (+ black ring inside)
1 gray front casing
1 coil stand (black with metal contact, lifted and pulled out)
1 Coil on metal frame (two wires out of the coil to the circuit board, pushed out of its stand)
1 White peg (to be in connection with the setting knob)
1 gear “movie real” IT (inside top) on
1 gear off axis I2T (inside 2nd top)
1 transparent peg on
1 black stand
1 circuit board (PCB1 for Printed Circuit Board 1) (1 resistor, 1 transistor, 2 capacitors, 1 metal thing, must be the quartz)
1 white roller I3T on top
1 gear I4T with little peg
1 gear I5T popped out of the gear box base
1 gear box base
Bell sub-system
Double-ring bell ringer
Motor plus capacitor
Bell on black plastic stand
Exploded View on next page
BILL OF MATERIALS
5 subsystems, 32 parts
Guivarch, Lee, TudrynMechanical Assembly and its roleSeptember 2001
in Product Development
Front Casing Subsystem FC
10 parts
Front casing FC1
Clock paperFC2
Battery + contactFC3
Battery – contactFC4
LEDFC5
Transparent clock coverFC6
Alarm handFC7
Hour handFC8
Minute handFC9
Second handFC10
SPRING SLIDE SS
7 parts
Base SS1
SlideSS2
SpringSS3
Electric contact holderSS4
Electric contact bumperSS5
Metal contacts SS6 (comes with SS5)
& SS7
BELL SUBSYSTEM BSS
6 parts
SupportBSS1
MotorBSS2
Ring holderBSS3
Rings (2x, no difference)BSS4
BellBSS5
CapacitorBSS6
GEAR BOX GB
4 parts
Gear boxGB1
Gear box switchGB2
Printed Circuit BoardGB3
Flex cableGB4
BACK CASING SUBSYSTEM BC
5 parts
Back casing BC1
Battery coverBC2
Alarm buttonBC3
On / off switchBC4
Knob setterBC5
Not counted: wires
screws
Mechanical Assembly for Product DevelopmentSeptember 12th 2001
Assignment 1
DESCRIPTION OF EACH PART
PART # / NAME / FUNCTION / COMMENTS / MATERIAL / COLORFC (Front Casing)
FC1 / Front cover / Injection molded thermoplastic*:
Acrylic Resin
Hard, not brittle, smooth glass-like surface / Light grey
FC2 / Clock paper
FC3 / Battery + contact / Aluminum
FC4 / Battery – contact / Aluminum
FC5 / LED / Acrylic Resin casing with diode inside
FC6 / Transparent clock cover / Acrylic Resin / Transparent
SS (Spring Slide)
SS1 / Base / The only reason for this part to exist is that the gear box was outsourced, otherwise the slide would go directly on GB1 / Acrylic Resin / Black
SS2 / Slide / Acrylic Resin / Black
SS3 / Spring / Steel
SS4 / Electric contact holder / Acrylic Resin / Black
SS5 / Electric contact bumper / Acrylic Resin / Black
SS6 / Metal contact / Comes with SS5 / Copper
SS7 / Metal contact / Copper
BSS (Bell Subsystem)
BSS1 / Support / Acrylic Resin / Black
BSS2 / Motor / Probably outsourced
BSS3 / Ring holder / Acrylic Resin / Black
BSS4 / Rings / The two rings have no difference: same part number but quantity 2 / Aluminum
BSS5 / Bell / Steel
BSS6 / Capacitor
PART # / NAME / FUNCTION / COMMENTS / MATERIAL / COLOR
GB (Gear Box)
GB1 / Gear box / Contains extra room for internal battery, has instructions carved on the plastic: probably outsourced and used in another product, that is why we chose not to include it in our analysis / Acrylic Resin / Black
GB2 / Gear box switch / A slot stops the sliding movement
One spring cantilever makes sure the switch is not in an intermediate position / Acrylic Resin / Black
GB3 / Printed Circuit Board / Simple connecting role (no electric components, just wires soldered) / Copper, Silicium / Green
GB4 / Flex cable / Copper / Grey
GB5 / Alarm hand / Acrylic Resin / Grey
GB6 / Hour hand / Acrylic Resin with fluorescent material / Black + fl. green
GB7 / Minute hand / Acrylic Resin with fluorescent material / Black + fl. green
GB8 / Second hand / Acrylic Resin / Silver
BC (Back Casing)
BC1 / Back casing / Acrylic Resin / Dark grey
BC2 / Battery cover / Acrylic Resin / Dark grey
BC3 / Alarm button / Acrylic Resin / Silver
BC4 / On / off switch / Made to match the size of GB2 black knob (probably not designed by the same company) / Acrylic Resin / Light grey
BC5 / Knob setter / Sets both alarm and time depending on the depth of insertion of the knob / Acrylic Resin / Black
* Thermoplastics are materials that flow when introduced to high heat. They are moldable under this high heat and pressure. This process molds plastic resins. Injection molding machines are used to form almost all the parts of this alarm clock. The plastic resin is added to the machine along with any dyes or colors. Once the resin moves to the barrel, it is heated to a their specific melting temperature. Once the resin is “melt”, it is added to the mold. The plastic in the mold cools and becomes a solid part.
( Taken from and )
LIST OF MATES
Note: a line beginning with "+" means that te part to the right of the + sign is assembled with the (sub)system resulting of the lines above
Inches / =(D-d)/D
Parts involved / Description of assemby / D / d / c / Comments
1. SUB-ASSEMBLY MATES
FC (Front Casing)
FC1 + FC2 / The clock paper (FC2) is glued onto the front casing: width
length / 2.558 / 2.543 / 0.006 / Very small clearance but easy fit (flexibility of the paper, glue dries slowly)
4.25 / 4.245 / 0.001
FC1 + FC3 / The + battery contact snaps into its location / 0.623 / 0.585 / 0.061 / Small clearance, difficulty
FC1 + FC4 / The - battery contact snaps into its location / 0.623 / 0.585 / 0.061 / Small clearance, difficulty
FC1 + FC5 / The LED is inserted into its location and glued / 0.134 / 0.116 / 0.134 / Little difficulty
FC1 + FC6 / The transparent clock cover snaps onto FC1, 3 notches / 0.214 / 0.19 / 0.112 / Very small clearance, large difficulty
cover itself in the compartment: length / 4.248 / 4.238 / 0.002 / Very small clearance, large difficulty
width / 2.56 / 2.538 / 0.009 / Very small clearance, large difficulty
SS (Spring Slide)
SS1 + SS2 / The slide (SS2) snaps onto the base by one point cantilever contact (two different widths) / 0.546 / 0.532 / 0.026 / Narrow insertion, but well guided by the
cantilever
0.558 / 0.536 / 0.039
Height clearance impossible to measure
SS3 + SS1 & SS2 / The spring has two rings at its extremities that go around pins on the base and the slide / 0.148 / 0.132 / 0.108 / No difficulty of insertion (the rings on the
spring are also deformable)
Other end of the spring / 0.148 / 0.112 / 0.243
+ SS4 / The electric contact holder is snap fitted into a hole of the base / (irrelevant)
SS5 to SS7 / We have not identified how those were brought together. They were probably not assembled, but the plastic molded around the copper contacts.
BSS (Bell Subsystem)
BSS1 + BSS2 / Snap fit with two cantilevers
Two position pins on support to be matched with two holes on motor (to prevent the motor form rotating inside the support) / 0.825 / 0.82 / 0.006 / Very small clearance, large difficulty
BSS2 + BSS3 / Ring holder (BSS3) inserted onto the motor peg / 0.078 / 0.078 / 0.000 / Zero clearance, large difficulty (but little precision on so small lengths)
BSS3 + BSS4 / Rings are inserted by deformation of the support / (irrelevant)
BSS1 + BSS5 / The bell is inserted once for all on the support peg by deforming four metal notches that hold it tight afterwards
BSS2 + BSS6 / Capacitor soldered onto the motor
Inches / =(D-d)/D
Parts involved / Description of assemby / D / d / c / Comments
GB (Gear Box)
GB1 + GB2 / The gear box switch (GB2) slides into place in the gear box by 4 point cantilever connection: part width / 0.875 / 0.853 / 0.025 / Pretty small clearance
A slot on the part matches with a peg on GB1. It allows GB2
to slide back and forth / 0.087 / 0.079 / 0.092 / Larger clearance
GB1 + GB4 + GB3 / Soldered
BC (Back Casing)
BC1 + BC2 / The battery cover (BC2) snaps into the battery compartment of the back casing: three kinds of contact
Width / 2.206 / 2.195 / 0.005 / Small clearance, although, little difficulty
Small notch / 0.197 / 0.172 / 0.127 / Little difficulty
Large notch / 0.206 / 0.176 / 0.146 / Little difficulty
BC1 + BC3 / The alarm button is inserted in its compartment: length / 2.37 / 2.35 / 0.008 / Small clearance, although, little difficulty
width / 0.738 / 0.696 / 0.057
BC1 + BC4 / The on/off switch is inserted in the back casing / 0.237 / 0.226 / 0.046
BC1 + BC5 / The knob setter is inserted in the back casing / 0.204 / 0.174 / 0.147 / Little difficulty
2. FINAL ASSEMBLY MATES
SS + GB / Insertion within two screw holes / 0.174 / 0.157 / 0.098 / Easy insertion
FC3 & FC4 + GB3 / Soldered
SS6 & SS7 + GB3 / 2 wires, soldered
FC5 + GB3 / 2 wires, soldered
BSS + GB3 / 2 wires, soldered
+ FC: details
FC1 + BSS / Insertion and 2 screws: peg 1 / 0.201 / 0.193 / 0.040 / Rather small clearance (friction is felt)
peg 2 / 0.203 / 0.192 / 0.054 / Rather small clearance (friction is felt)
FC1 + GB1 / Insertion within the same screw holes as (SS+GB), 2 screws / 0.167 / 0.146 / 0.126 / Easy insertion
BC4 + GB2 / Insertion of the on/off switch onto the black knob switch of GB2 / 0.226 / 0.225 / 0.004
length, width / 0.112 / 0.108 / 0.036
+BC / BC1 snap fits onto FC1on six points, 3 screws: width / 3.565 / 3.497 / 0.019 / Small clearances, but the casings can change their shape during insertion to adjust
(note: BC has to be upside-down so that BC3 length / 5.225 / 5.183 / 0.008
does not fall) notches / 0.435 / 0.399 / 0.083
BC5 + GB1 thru BC / Insertion of the knob setter of the GB1 axis, hexagonal peg to ensure that no relative rotation occurs between them / 0.195 / 0.189 / 0.031
GB5 + GB1 / Clearance fit of the alarm hand on the front side of the GB / 0.192 / 0.181 / 0.057 / The peg on the front side of GB1 has a stair shape to receive the different diameters of the hand, small clearances are enough to hold the hands firmly
GB6 + GB1 / Clearance fit of the hour hand on the front side of the GB / 0.133 / 0.12 / 0.098
GB7 + GB1 / Clearance fit of the minute hand on the front side of the GB / 0.08 / 0.076 / 0.050
GB8 + GB1 / Clearance fit of the second hand in the hollow axis of the front side of the GB: too small to measure anything
Mechanical Assembly for Product DevelopmentSeptember 12th 2001
Assignment 1
Pictures of parts
Mechanical Assembly for Product DevelopmentSeptember 12th 2001
Assignment 1