U.S. patent number 3,759,031 [Application Number 05/220,922] was granted by the patent office on 1973-09-18 for modular solid state wristwatch.
This patent grant is currently assigned to HMW Industries, Inc.. Invention is credited to Cleon W. Hougendobler, Robert E. McCullough.
United States Patent |
3,759,031 |
McCullough , et al. |
September 18, 1973 |
**Please see images for:
( Certificate of Correction ) ** |
MODULAR SOLID STATE WRISTWATCH
Abstract
Disclosed is a solid state wristwatch having no moving parts and
utilizing a digital time display of light-emitting diodes. The
watch features a modular construction for ease of assembly and
reliability. Also disclosed is a setting magnet for the watch
stored in the watch bracelet.
Inventors: |
McCullough; Robert E.
(Lancaster, PA), Hougendobler; Cleon W. (East Petersburg,
PA) |
Assignee: |
HMW Industries, Inc.
(Lancaster, PA)
|
Family
ID: |
22825571 |
Appl.
No.: |
05/220,922 |
Filed: |
January 26, 1972 |
Current U.S.
Class: |
368/70; 368/241;
968/449; 968/823; 968/878; 968/928; 368/204 |
Current CPC
Class: |
G04G
9/0017 (20130101); G04G 17/02 (20130101); G04C
3/004 (20130101); G04F 5/06 (20130101) |
Current International
Class: |
G04F
5/06 (20060101); G04G 17/02 (20060101); G04G
9/00 (20060101); G04C 3/00 (20060101); G04G
17/00 (20060101); G04F 5/00 (20060101); G04b
019/30 (); G04b 037/04 (); G04b 027/00 () |
Field of
Search: |
;58/23R,23A,23AC,5R,85.5,88,9R |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Wilkinson; Richard B.
Assistant Examiner: Jackmon; Edith C. Simmons
Claims
What is claimed and desired to be secured by United States Letters
Patent is:
1. A timepiece of sufficiently small size for use as a wristwatch
comprising a case, a one-piece frame of electrical insulating
material mounted in said case, a frequency standard and an
electro-optical display in said case, a frequency converter and a
display actuator coupling said frequency standard to said display,
said frequency standard, frequency converter, display actuator and
electro-optical display all being mounted in said case on said
one-piece frame, a battery removably mounted on said frame, said
battery being mounted on one side of said frame and said
electro-optical display being mounted on the other said of said
frame, said battery being electrically coupled to said display
through apertures in said frame, said frequency standard comprising
an oscillator including a trimmer capacitor, said capacitor being
mounted on the same side of said frame as said battery.
2. A timepiece according to claim 1 wherein said case includes a
removable back plate for easy access to said battery and said
trimmer capacitor.
3. A timepiece according to claim 2 wherein said oscillator
includes a crystal mounted on said other side of said frame.
4. A timepiece according to claim 3 including a substrate mounted
on said other side of said frame, the remainder of said oscillator,
said frequency converter, said display actuator and said display
all being mounted on said substrate.
5. A timepiece according to claim 4 wherein said substrate carries
printed circuit leads for interconnecting the components of said
oscillator, frequency converter, display actuator and display.
6. A timepiece according to claim 4 wherein said frequency
converter is formed by part of a single integrated circuit chip
mounted on said substrate.
7. A timepiece according to claim 4 including a pair of pins
passing through said frame for making electrical contact with the
terminals of said battery, and positive and negative lead frames
between respective ones of said pins and said substrate for
establishing electrical connection from said battery to said
components of said oscillator, frequency converter, display
actuator and display.
8. A timepiece according to claim 7 wherein said lead frames each
include at least one end turned over the edge of said substrate and
connected to the side of said substrate remote from said pins.
9. A timepiece of sufficiently small size for use as a wristwatch
comprising a one-piece circular frame of electrical insulating
material, said frame including cavities on one side, a trimmer
capacitor in one of said cavities, the other of said cavities being
adapted to removably receive a battery, said frame including a
cavity on its other side receiving a crystal, means passing through
said frame electrically coupling said trimmer capacitor and said
crystal, said trimmer capacitor and said crystal forming part of a
crystal oscillator, a substrate mounted on said other side of said
frame, said substrate carrying the remainder of said crystal
oscillator, a divider on said substrate coupled to the output of
said oscillator, a display actuator on said substrate coupled to
the output of said divider, and an electro-optical display on said
substrate coupled to the output of said display actuator.
10. A timepiece according to claim 9 wherein said display comprises
a plurality of light-emitting diodes.
11. A timepiece according to claim 9 wherein said trimmer
capacitor, said crystal and said substrate are secured to said
frame by silicone rubber adhesive to absorb shock.
12. A timepiece according to claim 9 wherein said other side of
said frame is provided with additional cavities, and a magnetic
switch mounted in each of said additional cavities.
13. A timepiece according to claim 12 wherein said magnetic
switches comprise a pair of setting switches and a demand
switch.
14. A timepiece according to claim 13 wherein said switches are
reed switches and are secured to said frame by silicone rubber
adhesive potting material.
15. A timepiece according to claim 9 wherein said frame is provided
with a pair of diametrically opposite mounting apertures for
securing said frame to a watch case.
16. A wristwatch comprising a casing, a wristband attached to said
casing, timekeeping means in said casing including at least one
magnetic setting switch, a permanent magnet for actuating said
setting switch, and means on said wristwatch for mounting said
permenant magnet when not in use.
17. A wristwatch according to claim 16 wherein said wristband
comprises a bracelet, said mounting means being provided on said
bracelet.
18. A wristwatch according to claim 17 wherein said mounting means
comprises a plate with turned-over edges adapted to retain said
magnet, said plate being pivoted to said bracelet.
19. A wristwatch according to claim 18 wherein said bracelet
includes a buckle, said plate being attached to said buckle for
pivotal movement of one end away from said buckle inwardly of said
bracelet toward the wearer's wrist.
20. A wristwatch according to claim 19 including cooperating snap
means on said buckle and plate for retaining said plate in its
closed position substantially parallel with said wristband.
Description
This invention relates to a solid state timepiece and more
particularly to an electronic watch which employs no moving parts.
In the present invention, a frequency standard in the form of a
crystal oscillator acts through solid state electronic circuit
dividers and drivers to power in timed sequence the light-emitting
diodes of an electro-optic display. In particular, the present
invention is directed to a modular wristwatch construction in which
substantially all the electrical circuitry is constructed using
large-scale integrated circuit techniques and the various watch
components are of modular construction for ease of assembly,
replacement, and repair.
Battery-powered wristwatches and other small portable timekeeping
devices of various types are well known and are commercially
available. The first commercially successful battery-powered
wristwatch was of the electromechanical type shown and described in
assignee's U.S. Pat. No. RE.26,187, reissued Apr. 4, 1967, to John
A. Van Horn et al. for ELECTRONIC WATCH.
In recent years, considerable effort has been directed toward the
development of a wristwatch which does not employ an
electromechanical oscillator as the master time reference. For
example, in assignee's U.S. Pat. No. 3,560,998, issued Feb. 2,
1971, there is shown a wristwatch in which the master time
reference is formed by a high frequency oscillator connected to the
watch display through a divider formed of low power complementary
MOS transistor circuits. In assignee's U.S. Pat. No. 3,576,099,
issued Apr. 27, 1971, there is disclosed a watch construction in
which the optical display is described as a plurality of
light-emitting diodes which are intermittently energized to assure
minimum power consumption and an increasingly long life for the
watch battery. Improved watch constructions of this general type
incorporating solid state circuits and integrated circuit
techniques are disclosed in assignee's copending U.S. patent
applications Ser. No. 35,196, filed May 6, 1970, now U.S. Pat. No.
3,672,155 and Ser. No. 143,492, filed May 14, 1971, among
others.
The present invention is directed to an improved watch construction
of the same general type as disclosed in the above-mentioned
applications and patents and one which utilizes no moving parts to
perform the timekeeping function. In particular, the present
invention is directed to a modular electronic wristwatch
construction in which substantially all of the electrical
components are formed on a single large-scale integrated circuit
chip and in which the other principal watch components are also of
modular construction so that the watch may be manufactured
utilizing standardized mass production techniques. The essentially
one-piece construction of the watch of this invention provides for
greater reliability, ease of assembly, ease of maintenance, and a
resulting watch is less expensive to manufacture and evidences
increased shock and impact resistance.
In the present invention, a frequency standard in the form of a
crystal controlled oscillator is coupled through an integrated
circuit frequency divider and a display actuator to an
electro-optic digital display in the form of a plurality of
light-emitting diodes. Mounted in the wristwatch case is a rugged
impact-resistant, one-piece module frame which houses the entire
wristwatch assembly, including the wristwatch battery. Secured in
the rear side of the module frame are a pair of battery cells and
an oscillator trimmer capacitor so that ready access may be had to
the cells and the trimmer by removal of the watch case back.
Mounted on the upper side of the frame is the timekeeping assembly,
including a wristwatch module comprising an electro-optical
display, single large-scale integrated circuit chip, oscillator
crystal, switches and associated watch components.
The watch display is visible through a red-colored filter and is
formed from a plurality of light-emitting diodes which are
preferably arranged in a seven-bar segment array. The
light-emitting diodes are energized in appropriate time
relationship with an effective brightness determined by an
intensity control circuit utilizing a photosensitive detector.
Situated on the front of the watch adjacent the display is a
pushbutton demand switch which when depressed instantly activates
the appropriate visual display stations. Minutes and hours are
programmed to display for 1 1/10th seconds, with just a touch of
the demand switch. Continued depression of this switch causes the
minutes and hours data to fade and the seconds to immediately
appear. The seconds continue to count as long as the operator
depresses the demand button. Computation of the precise time is
continuous and completely independent of whether or not time is
displayed.
Setting is accomplished by actuating either an hours-set switch or
a minutes-set switch, both of which are preferably magnetic field
responsive reed switches. The hours-set switch rapidly advances the
hours without disturbing the timekeeping of the minutes and
seconds. Actuation of the minutes-set switch automatically zeros
the seconds, while advancing the minutes to the desired
setting.
The watch of the present invention is virtually shock-proof and
water-proof, regardless of the environment in which it is placed.
The electrical components are mounted in a one-piece module frame
and preferably encapsulated in a potting compound so that no
mechanical forces or corrosive elements can attack the principal
components of the watch. Since there is no conventional stem for
winding or setting, the small shaft sealing problem is eliminated.
No maintenance or repair is normally necessary since the components
are sealed and substantially inaccessible to influences from the
outside world. All solid state electrical components, including the
light-emitting diode displays, have a virtually unlimited life.
In addition to the modular construction, other important features
of the present invention include the use of a large-scale
integrated circuit in the form of a single chip. The display digits
are individually strobed to reduce power consumption, and the final
assembly of the module to the frame is effected by only nine simple
electrical connections. In addition, provision is made in the watch
bracelet for incorporating a permanent setting magnet by which the
hours and minutes displays of the watch may be set.
Modular construction allows the substitution of other subassemblies
of various components and provides a rugged, impact-resistant,
one-piece construction. Durable lead frame connections between the
cells and the electrical substrate are provided and all components
are individually sealed and mounted in potting compound for
adherence to the module frame and for high shock resistance. A
simplified arrangement for mounting the module in the watch case
requires only two case screws and there is no mechanical or
electrical linkage to the outside of the case.
It is therefore one object of the present invention to provide an
improved electronic wristwatch.
Another object of the present invention is to provide a wristwatch
which utilizes no moving parts for performing the timekeeping
function.
Another object of the present invention is to provide a completely
solid state electronic wristwatch of improved modular
construction.
Another object of the present invention is to provide a small,
lightweight, portable timepiece suitable for use as a wristwatch
incorporating a single large-scale integrated circuit chip which
includes a vast majority of the electrical components of the
timepiece.
Another object of the present invention is to provide an improved
wristwatch construction in which substantially all modular
components are mounted in a rugged, impact-resistant, one-piece,
injection-molded modular frame.
Another object of the present invention is to provide an improved
wristwatch in which the principal watch components are joined by a
minimum of electrical connections during assembly.
Another object of the present invention is to provide a wristwatch
bracelet including a compartment for storing a watch setting
permanent magnet.
Another object of the present invention is to provide an improved
wristwatch and wristwatch case assembly wherein rapid and easy
access may be had to the watch batteries and to the time standard
trimming capacitor for easy replacement or adjustment.
Another object of the present invention is to provide a watch
construction in which the components are mounted in a resilient
potting composition for both adherence to the module frame and for
high shock resistance.
Another object of the present invention is to provide a wristwatch
construction in which the major components are individually sealed
before assembly.
Another object of the present invention is to provide a wristwatch
construction in which electrical portions of the watch are
interconnected by a durable lead frame.
Another object of the present invention is to provide a solid state
watch incorporating a circular movement for ease of incorporation
into a variety of wristwatch case constructions and designs.
Another object of the present invention is to provide a simplified
and less expensive solid state watch having increased reliability
of operation and increased resistance to shock.
These and further objects and advantages of the invention will be
more apparent upon reference to the following specification,
claims, and appended drawings, wherein:
FIG. 1 is a plan view of a wristwatch and a portion of a wristwatch
bracelet constructed in accordance with the present invention;
FIG. 2 is an exploded view showing the principal components of the
watch case forming a part of the wristwatch of FIG. 1;
FIG. 3 illustrates the watch case of FIG. 2 with the timekeeping
module inserted in the case;
FIG. 4 is a rear plan view of the watch of FIG. 1 showing the watch
case completely assembled;
FIG. 5 is a simplified block diagram of the electrical circuit for
the wristwatch of the present invention;
FIG. 6 is a more detailed block diagram of the electrical
circuit;
FIG. 7 is a top plan view of the substrate assembly of the watch of
the present invention illustrating the digital display;
FIG. 8 is a cross section showing the manner of mounting the single
integrated circuit chip forming a part of the substrate assembly of
FIG. 7;
FIG. 9 is a bottom plan view of the integrated circuit chip of FIG.
8;
FIG. 10 is a top plan view of the display module forming a part of
the assembly of FIG. 7;
FIG. 11 is a bottom plan view of the display module of FIG. 10;
FIG. 12 illustrates the diode-to-pin connections for the display
package of FIGS. 10 and 11;
FIG. 13 shows the pin interconnections for the display package of
FIGS. 10 and 11;
FIG. 14 is a top plan view of the module frame;
FIG. 15 is a cross section through the module frame taken along
line 15--15 of FIG. 14;
FIG. 16 is a bottom plan view of the module frame of FIGS. 14 and
15;
FIG. 16A is a cross section through the center of the module frame
taken along lines 16A--16A of FIG. 16;
FIG. 17 is a top plan view of the positive lead frame for forming
the battery connections in the wristwatch of the present
invention;
FIG. 18 is a top plan view of the module frame of FIG. 14 with
positive and negative lead frames, switches and crystal mounted in
it;
FIG. 19 is a similar top plan view of the module frame with all
components attached and illustrating the complete module;
FIG. 20 is a cross section through the module taken along line
20--20 of FIG. 19;
FIG. 21 is a bottom plan view of the module of FIGS. 19 and 20;
FIG. 22 is a cross section through the module taken along line
22--22 of FIG. 21;
FIG. 23 is a plan view of a setting magnet constructed in
accordance with the present invention;
FIG. 24 is an end view of the magnet of FIG. 23;
FIG. 25 is a partial perspective view of the watch bracelet showing
a buckle mounting for the setting magnet of FIGS. 23 and 24;
FIG. 26 is a plan view of the magnet holder of FIG. 25; and
FIG. 27 is a cross section through the magnet holder taken along
line 27--27 of FIG. 26.
Referring to the drawings, FIG. 1 is a top plan view of the
wristwatch constructed in accordance with the present invention,
the watch, generally indicated at 10, comprising a non-magnetic
metallic watch case 12 having a viewing window 14. The window is
preferably formed by a suitable red light filter, such as a
transparent red plastic or a ruby material. Attached to case 12 is
a wristwatch bracelet 16 and mounted on the case is a pushbutton
demand switch 18.
FIG. 2 is an exploded view showing the components of the watch case
12. These comprise a cover 20 mounting the light filter 14, a back
plate 22, an O-ring sealing gasket 24, and an externally threaded
attachment ring 26. Cover 20 is provided with a pair of mounting
holes 28 and 30 which extend only partway through the cover and
which are adapted to receive the ends of mounting screws for
mounting a time computer module inside case cover 20. The cover is
also internally stepped, as at 32, to receive sealing ring 24 and
is internally threaded, as at 34, to receive and engage with the
external threads on attachment ring 26.
FIG. 3 shows the cover 20 with a time computer module of circular
configuration, illustrated at 36, as completely received within the
cover. Time computer module 36 is attached to the cover solely by a
pair of mounting screws 38 and 40 which pass through the module and
are threadedly received in the mounting holes 28 and 30,
illustrated in FIG. 2. Module 36 is provided with a pair of
circular cavities 42 and 44, each of which is adapted to receive a
11/2 volt, 1 cell battery. The batteries are connected in series to
form a battery power supply of 3 volts.
FIG. 4 is a bottom plan view of a completely assembled watch case.
As illustrated in FIG. 4, ring 26 is preferably provided with a
pair of diametrically opposite indentations 46 and 48 adapted to be
engaged by the ends of a bifurcated tool so that the ring may be
rotated to tighten the assembly. In assembling the watch, the time
computer module 36 is first inserted into the cover 20 and secured
by the screws 38 and 40. O-ring seal 24 is then inserted on to the
step 32 in the cover and the back plate 22 placed over the O-ring
seal. Finally, attachment ring 26 is placed so that it overlies the
outer edge of back plate 22 and the ring 26 is rotated into tight
threaded engagement with the internal threads 34 on cover 20. It is
a feature of the assembly that the screws 38 and 40 automatically
angularly orient or align the time computer module 36 with the
cover 20 and the viewing window 14. Back plate 22 is preferably
also provided with an alignment tab 50 (FIG. 2) which slides into a
shallow groove 52 in the cover so that the back plate 22 is also
automatically aligned with the cover. Only attachment ring 26 is
rotated to tighten the back plate to the cover and compress sealing
ring 24.
FIG. 5 is a simplified block diagram of the principal operating
components of the watch. These comprise a time base or frequency
standard 56, preferably in the form of a crystal oscillator
producing an electrical output on lead 58 at a frequency of 32,768
Hz. This relatively high frequency is supplied to a frequency
converter 60 in the form of a divider which divides down the
frequency from the standard 56 so that the output from the
converter 60 appearing on lead 62 is at a frequency of 1 Hz. This
signal is applied to a display actuator 64 which, in turn, drives
an electrooptical display, indicated at 68, and viewable through
window 14, by way of electrical lead 66. While only an hours and
minutes display is shown, it is understood that with the operation
of the pushbutton 18 of FIG. 1, the hours and minutes are first
displayed for a predetermined time and if the pushbutton remains
depressed, the hours and minutes are extinguished and the seconds
become visible. The same display diodes are used for both minutes
and seconds since these are not displayed simultaneously, thus
minimizing the power drain from the watch battery.
In normal operation, time is continuously being kept but is not
displayed through the window 14. That is, no time indication is
visible through the window and this is the normal condition which
prevails in order to conserve battery energy in the watch. However,
even though the time is not displayed through the window 14, it is
understood that the watch 10 continuously keeps accurate time and
is capable of accurately displaying this time at any instant. When
the wearer or operator desires to ascertain the correct time, he
depresses the pushbutton 18 with his finger and the correct time is
immediately displayed at 68 through the window 14, which shows a
light-emitting diode display giving the correct time reading of
10:10, namely, 10 minutes after 10 o'clock. The hours and minutes,
i.e., 10:10, are displayed through the window 14 for a
predetermined length of time, preferably 11/4 seconds, irrespective
of whether or not the pushbutton 18 remains depressed. The exact
time of the display is chosen to give the wearer adequate time to
consult the display to determine the hour and minute of time.
Should the minutes (or hours) change during the time of display,
this change is immediately indicated by advancement of the minute
(or hour) reading to the next number, i.e., 11, as the watch is
being read. If the pushbutton 18 remains depressed, at the end of
11/4 seconds the hours and minutes of the display are extinguished,
i.e., they disappear, and simultaneously the seconds reading is
displayed through the window 14 by the same diodes as previously
displayed the minutes. The advancing seconds cycling from 0 to 59
continue to be displayed through window 14 until the pushbutton
switch 18 is released.
FIG. 6 is a more detailed diagram of the electrical circuit of the
watch 10 of the present invention. In FIG. 6, the electro-optic
display is again illustrated at 68 and the majority of the
electrical components of the watch are illustrated in FIG. 6 as
incorporated in a single large-scale integrated circuit chip
identified by the reference numeral 70. For a detailed disclosure
of the electrical components incorporated in chip 70 and for a
detailed discussion of the other components of the watch, reference
may be had to assignee's copending U.S. patent application Ser. No.
143,492, filed May 14, 1971, which entire application is
incorporated herein by reference. In addition to the integrated
circuit chip 70, the watch comprises the frequency standard 26
which, in the preferred embodiment, takes the form of a crystal
controlled oscillator formed from a complementary MOS FET inverter.
Again, reference may be had to the above-identified copending U.S.
patent application Ser. No. 143,492 for a detailed description of
the oscillator. It comprises a piezoelectric frequency determining
crystal 63, a variable capacitor or trimmer 65 for fine adjustment
of the oscillator frequency, a bias resistor 61, and a pair of
complementary MOS transistors (not shown) incorporated in circuit
chip 70. This chip also includes the frequency converter 60 of FIG.
5 and a large portion of the display actuator 64. The watch also
comprises a battery 72 which, by way of example only, may comprise
a conventional 3 volt wristwatch battery formed from a pair of
series connected 11/2 volt cells. Connected to the positive side of
the battery 72 is a resistor 73. The battery energizes the display
68 which is shown in FIG. 6 as consisting of a pair of hours
stations comprising the digits station 74 and tens station 76 and a
pair of combination minutes and seconds stations comprising digits
station 78 and tens station 80. In addition, the display 68
includes a pair of colon dots 81, each formed by a single
light-emitting diode. The display stations 74, 76, 78, and 80 are
preferably formed from a 7-bar segment array of light-emitting
diodes, such as those formed from gallium arsenide phosphide which
produce light in the visible red region. The display stations are
energized from the integrated circuit chip 70 connected to battery
72 by way of a plurality of leads 79. The circuit is completed from
the leads 79 to the anodes of the light-emitting diodes and the
cathodes of the light-emitting diodes are individually connected to
the other side of the power supply through strobing or switching
N-P-N junction transistors 82, 84, 86, 88, and 90. There is a
separate lead 79 for the total number of bar segments in a display
station, i.e., seven leads 79. That is, with a 7-bar segment
display, there are seven leads 79, each one connected to a separate
bar segment of each station as more fully described below. However,
all the cathodes of each station are connected in common through
the N-P-N junction transistor for that display. The two bar
segments 94 and 96 for the hours tens display have their cathodes
connected to transistor 82, as do the colon dots 81. All cathodes
of the hours units station 74 are connected to transistor 84.
Display stations 78 and 80 are used to display both minutes and
seconds so that that station 80 has the cathodes of all diodes
connected to transistor 86, referred to as the minutes transistor,
and to transistor 90 which acts as the seconds transistor.
Similarly, all the diode cathodes of display station 78 are
connected to a minutes transistor 88 and a seconds transistor 92.
These transistors have their bases returned to the integrated
circuit chip 70 through current limiting resistors 98, 100, 102,
104, 106, and 108, the emitters of the transistors being connected
in common to the negative side of the power supply battery 72, as
indicated at 110.
The anodes of the bar segment diodes are energized from bipolar
driver transistors illustrated in FIG. 6 as the P-N-P junction
transistors 112, 114, 116, 118, 120, 122, and 124. Since the
greatest number of bar segments at any display station is seven,
there are seven driver transistors and seven corresponding leads
79. The transistor collectors are connected to the display diodes
through individual ones of current limiting resistors 126 and the
driver transistor bases are connected to the integrated circuit
chip 70 through protective resistors 128. The emitters of the
driver transistors are connected in common as at 130 to the
positive side of power supply battery 72.
Also external to the integrated circuit chip 70 in FIG. 6 is a
demand or read switch 132 which is closed when the button 18 of
FIG. 1 is depressed. Further manually operated switches external to
integrated circuit chip 70 are minutes set switch 134 and hours set
switch 136. These switches are connected across battery 72 from the
positive side of the battery to the negative side through
respective series resistors 138, 140, and 142. The resistors
associated with the switches are used in order to ground the
corresponding inputs, otherwise the corresponding inputs would be
floating and could be anything. When closed, the switches are used
to switch the input voltages from ground to plus.
A feature of the watch of the present invention is that the
intensity of the light emitted from the display diodes is varied in
accordance with ambient light. That is, the diode light intensity
is increased for greater contrast when the ambient light is bright,
such as during daytime display, whereas the intensity of the light
from the diodes is decreased when ambient light decreases. The
automatic display intensity control circuitry is generally
indicated at 144 in FIG. 5 and comprises a photosensitive resistor
146 mounted on the face of the watch connected to the positive side
of battery 72 and to a resistor 148 and a capacitor 150. These
components are connected to the positive side of the power supply
through a series resistor 152. Other external components connected
to integrated circuit chip 70 include an internal information
lockout lead 154, a transmission gate control lead 156, and an
optional input or continuous display lead 158, all normally
grounded. A further connection to ground is through resistor 157
and the integrated circuit chip 70 is also provided with a carryout
lead and terminal 159.
FIG. 7 is a top plan view of a substrate assembly 160 which
comprises a mounting board 162 of ceramic or other suitable
insulating material to which are secured the electrical components
of FIG. 6 and on which are printed the connecting leads. Like parts
in FIG. 7 are similarly numbered to those in FIG. 6 and also
secured to the board or substrate is the integrated circuit chip,
generally indicated at 70, and the display 68.
FIGS. 8 and 9 show the construction of the integrated circuit chip
70. FIG. 8 is a cross section through the assembly and FIG. 9 is a
bottom plan view. The actual integrated chip itself, illustrated at
164 in FIG. 8, is mounted on the underside of a ceramic carrier
166. This carrier is provided with a plurality of spaced, stepped
feet 168 which are provided with conductive layers 170 to which are
attached leads 172 extending from the integrated circuit chip 164.
The chip is mounted in a suitable silicone rubber potting compound,
as illustrated at 174, which terminates short of the bottom of feet
168 so that the conductive surface 170 at the bottom is exposed for
making electrical connections. Ceramic carrier arrangements of this
type are well known and, by way of example only, are available
under the trade name of Versapak from Frenchtown C.F.I. of
Frenchtown, N.J.
FIG. 10 is a top plan view of the display package 68 and FIG. 11 is
a bottom plan view of the display package. The diodes are suitably
mounted on the top surface of the display package as illustrated at
176 in FIG. 10. External electrical connection to the display
package is effected through electrical conductors 177 secured to
the bottom surface of the package. The electro-optic display
package is preferably of laminated construction and, by way of
example only, may comprise three ceramic layers secured together
and encapsulated in a clear coating material to protect it from the
surrounding environment.
FIG. 12 shows the top layer with the diodes attached and
illustrates the manner of connection to the anodes of the
individual diodes. The two diodes 94 and 96, mounted on top ceramic
layer or board 178, are connected by short electrical leads 180 and
182 to the ends of a pair of conductive pins 184 and 186 which
extend through all three layers of the display package 68. Similar
pins 188 and 190 are provided for the colon dot diodes 81, and the
connections from the diodes to corresponding pins for the other
display stations are also illustrated. The respective diodes for
station 78 are labeled a-g and the display diodes for stations 74
and 80 are similarly arranged.
FIG. 13 is a plan view of the second layer or intermediate ceramic
board 192 forming the middle part of the display package 68. The
diodes are shown in dashed lines in FIG. 13, it being understood
that the diodes are mounted on the top surface of board 178 in FIG.
12 and the dashed line illustration is only for the purposes of
understanding the relationship between the interconnections
effected on this second layer 192. The pins which extend through
all three layers are similarly numbered in FIG. 13. It can be seen
from FIG. 13 that the a diodes of each of the display stations 74,
78 and 80 have their anodes interconnected by the leads 192 and 194
connected to the anode pins 196, 198, and 200. The diodes 94 and 96
for the hours one stations are interconnected through pins 184 and
186 to the b and c diodes of each of stations 74, 80, and 78, as
well as to the colon diodes 81, by way of pins 188 and 190. The
small d, e, f, and g diode interconnections are also illustrated in
FIG. 13.
As previously mentioned the interconnections illustrated in FIGS.
12 and 13 are for the diode anodes which receive signals from the
leads 79 in FIG. 6. The cathodes of all diodes in the particular
display station are interconnected by similar pins (not shown)
engaging the back sides of the diodes and by leads on the bottom or
third layer of the display package to provide a common cathode
interconnection to the respective transistors 82, 84, 86, 88, 90,
and 92, as illustrated in FIG. 6. Thus, the particular group of
diodes energized is dependent upon the conductive state of the
anode switching transistors 112, 114, 116, 118, 120, 122 and 124 in
FIG. 6 and the particular display station energized depends upon
the conductive state of the cathode transistors 82, 84, 86, 88, 90,
and 92 in FIG. 6. The anode signals determine the number to be
displayed, i.e., turn on the appropriate segments of the seven-bar
segment display, whereas the cathode transistors determine the
display station energized, i.e., the time being displayed whether
it be hours, minutes or seconds. Each of the stations 76, 74, 80,
and 78 is energized in sequence so that each station is turned on
only approximately one-quarter of the time. In this way, only one
display station is energized at any given instant, which effects a
strobing action to balance out the power drain on the battery. To
this end, the colon dot diodes 81 are tied in with the hours tens
station 76 since that station includes only two diodes and normally
draws less power than the other stations which each comprise
seven-bar segment diodes. The diodes are, of course, lit in
sequence at a sufficiently rapid rate to give the appearance of
constant illumination of the time to be displayed. When hours and
minutes are being displayed, all four stations are strobed in
sequence. When only seconds is being displayed, the colon dots are
not used and only stations 80 and 78 are strobed in sequence as
determined by the signals to the seconds transistors 90 and 92.
FIG. 14 is a top plan view of the frame 37 for module 36 and FIG.
15 is a cross section through the frame taken along line 15--15 of
FIG. 14. This frame is preferably formed from an impact-resistant,
one-piece, injection molded plastic material and, in the preferred
embodiment, is formed of fiber-filled S-2/30 type 6-10 Nylon which
is a fiber-filled Nylon material. FIG. 16 is a bottom plan view of
the frame 37. FIG. 16A is a cross section through the center of the
module frame taken along line 16A--16A of FIG. 16. Referring to
these FIGURES, the frame 37 is of circular or disc-shaped,
one-piece plastic construction and comprises a circular rim 202
integral with a solid central section 204 having an enlarged or
thickened portion 206 provided with the cavities or wells 42 and
44, each adapted to receive a 11/2 volt, 1 cell battery. At the
bottom of each well is a through hole or aperture 208 and 210, each
adapted to receive an electrically conductive metallic pin for
establishing electrical connection from the batteries in wells 42
and 44 to the remainder of the circuit. Enlarged central portion
206 is connected to the rim by tapered ribs for added strength,
such as are indicated at 212.
Referring to FIG. 16, the rim is provided with a pair of
diametrically opposite cutouts 214 and 216 defining flats through
which pass the mounting holes 218 and 220. These holes pass
completely through the frame and provide passage for the mounting
screws 38 and 40 of FIG. 3 by means of which the entire module
assembly is attached to the watch case. Also passing completely
through the module frame 37 are a second pair of apertures 222 and
224 which provide passage through the frame for leads establishing
electrical connection to the trimmer capacitor 65 of FIG. 6 in a
manner more fully described below. The trimmer capacitor is adapted
to be mounted in an elongated shallow groove or well 225 provided
in the back or bottom surface of the module frame and this trimmer
capacitor, along with the batteries in circular wells 42 and 44,
are the only components mounted on the back of the frame and the
only components accessible after removal of the back plate 22 of
the watch. Access to the batteries through the back plate is
desirable for battery replacement and access to the trimmer
capacitor is provided in order to make readily possible fine
adjustment of the oscillator frequency acting as the time
standard.
On the front and top surface of the module frame are three
elongated cavities or wells 226 (FIG. 14), 228 and 230, each
adapted to receive a magnetic reed switch. Well 230 receives the
demand switch 132 of FIG. 6 operated by pushbutton 18, whereas
cavities 226 and 228 receive the minutes and hours set switches 134
and 136 of FIG. 6. A larger cavity or well 232, near the top of the
module frame in FIG. 14, is adapted to receive the quartz crystal
63 of FIG. 6 forming a part of the time base oscillator. A network
of shallow grooves 234 are interconnected to an area surrounding
the battery aperture 212 and these grooves 234 are adapted to
receive corresponding portions of a conductive metal positive lead
frame 236, shown in plan view in FIG. 17. The positive lead frame
236 is formed from a flat blank of conductive metal, and by way of
example only, may have a uniform thickness of approximately .+-.
0.0045 inch, and may be formed of annealed copper plate or bright
tin plate or lead-free brass. Similarly, joined to an area
surrounding aperture 208 in FIG. 14 is a groove 238 adapted to
receive a negative lead frame formed of the same material and
having the same thickness as positive lead frame 236 of FIG. 17.
Both lead frames are secured in the grooves by suitable adhesive.
The module assembly 160 of FIG. 7 is placed over the lead frames in
the grooves 234 and 238 in a manner more fully described below.
FIG. 18 is a top plan view, similar to FIG. 14, showing the demand
switch 132 in the well 230 and the setting switches 134 and 136 in
the wells 226 and 228. Positive lead frame 236 is shown as received
in the grooves 234 and a similar negative lead frame 240 is shown
secured in groove 238. The enlarged circular portions 242 and 244
of the lead frame engage the ends of conductive pins passing
through the battery well apertures 208 and 210 of FIG. 16A. FIG. 18
shows the lead connection to the switches and also shows the quartz
crystal package 63 mounted in well 232 with the smaller adjacent
cavities or wells 246 and 248 providing access for lead connection
to the two terminals of the crystal 63. Finally, FIG. 18 shows the
mounting slot or cavity 250 for the pushbutton 18 which carries a
permanent magnet and when pushed in or depressed actuates reed
switch 132. The pushbutton construction and the reed switches are
not described in detail and reference may be had to assignee's
copending U.S. application Ser. No. 138,557, filed Apr. 29, 1971,
and entitled SOLID STATE WATCH WITH MAGNETIC SETTING, for a
detailed description of these elements, the complete disclosure of
which application is incorporated herein by reference.
FIG. 19 is a top plan view of the complete time computer module 36
with the substrate assembly 160 of FIG. 7 attached to the plastic
module frame 37. FIG. 20 is a cross section through the module
taken along line 20--20 of FIG. 19; FIG. 21 is a bottom plan view
of the module of FIGS. 19 and 20; and FIG. 22 is a cross section
through the module taken along line 22--22 of FIG. 21. These
FIGURES illustrate the frame 37 as receiving batteries 252 and 254
which are illustrated in FIG. 22 as connected in series by a
conductive spring 256 which, if desired, may be mounted on the back
plate 22 of the watch case. The negative side of battery 252 is in
conductive electrical engagement with a pin 258 and the positive
side of battery 254 is similarly in conductive electrical
engagement with a metal pin 260. Pin 258, in turn, engages the
enlarged portion 244 (FIG. 18) of negative lead frame 240 and pin
260 engages enlarged portion 242 of the positive frame 236.
Referring to FIG. 19, the trimmer capacitor leads which pass
through the apertures 222 and 224 are soldered to the printed
circuit of the substrate assembly 160 at 262 and 264. The positive
lead frame connected to the positive side of the power supply is
turned over the substrate assembly and soldered to the printed
circuit pad at 266. The leads for the three switches 134, 136, and
132 are soldered to the printed circuit pads as respectively
indicated at 268, 270, and 272. The negative lead frame is likewise
turned over the edge of the substrate assembly 160 and soldered to
the printed circuit at 274 in FIG. 19. A second positive lead frame
power supply solder connection is shown at 276 and the crystal lead
is soldered to a printed circuit pad at 278. Thus, it can be seen
that during final assembly only nine large, simple and readily
accessible solder connections need be effected to electrically
connect the entire assembly.
In the preferred embodiment, all components are preferably embedded
in a suitable potting compound and, in the preferred embodiment,
the potting compound is a silicone rubber potting composition
having good adhesive characteristics and good shock absorbing
qualities. The potting compound is indicated by the hatching at 280
in FIGS. 20 and 22. As best seen in FIG. 21, the trimmer capacitor
65 is preferably provided with an adjustment screw 282 so that when
the back plate of the case is removed, the screw 282 may be rotated
by a small screwdriver to provide adjustment of the oscillator
frequency.
FIG. 23 is a plan view and FIG. 24 is an end view of a setting
magnet which may be used to actuate the setting switches 134 and
136. For this purpose, the watch case, if desired, may be provided
with suitable indentations adjacent these switches so that the face
of the setting magnet may be placed in the indentations adjacent
the desired hours or minutes setting switch. The setting magnet,
generally indicated at 284 in FIGS. 23 and 24, comprises a holder
286 (preferably formed of non-magnetic material such as beryllium
copper or the like), to which is soldered a permanent magnet 288.
Holder 286 includes a projecting portion 290 which serves as a
handgrip for grasping the setting magnet 284 between the thumb and
forefingers. The holder 286 and magnet 288 are preferably
gold-plated and the magnet 288 is preferably magnetized after
plating to have a magnetism of 1,000 gauss minimum with the
polarity indicated as measured at the poles. When the magnet 288 is
placed adjacent either the hours setting reed switch or the minutes
setting reed switch, i.e., placed against the outer surface of the
case adjacent the switch, the switch is closed and appropriate
setting effected.
A feature of the watch of the present invention is that the
bracelet 16 is provided with a holder for housing the setting
magnet 284. To this end, as illustrated in FIG. 25, a portion of
the bracelet includes a buckle 292 hinged to the remainder of the
bracelet at each end and provided with a pivotally mounted magnet
holder 294 shown in FIG. 25 rotated to its substantially open
position. Holder 294 is preferably configured to receive the magnet
284 illustrated in FIGS. 23 and 24. FIG. 26 is a bottom plan view
of a portion of the buckle and magnet holder and FIG. 27 is a cross
section taken along line 27--27 of FIG. 26. Referring to FIG. 26,
the buckle 292 comprises a flat metal plate 296 with turnedover
edges which form parallel perpendicularly extending flanges 298 and
300. These flanges are preferably provided with a plurality of
apertures 302 adapted to receive pivots for attaching the buckle to
the remainder of the bracelet 16. The magnet holder or cover 294
likewise comprises a flat metal plate bent over along three edges
to define a flange 304. Rotatably received through suitable
apertures in this flange adjacent back edge 306 are a pair of pins
308 and 310 which are secured in two of the buckle apertures 302 so
that the holder 294 is free to pivot or rotate about pins 308 and
310. If desired, holder 294 may be spring-biased closed and it is
preferably provided with a pair of ball-like projections 312 and
314 which act as snaps and snap into two of the apertures 302 in
the buckle to retain the holder closed in the positions illustrated
in FIGS. 26 and 27. Flange 304 is preferably turned up at 316 so
that it may be engaged by the tip of the finger to lift the holder
and rotate it about pins 308 and 310 to expose the setting magnet
284 so that it might be removed and used to set the watch. The
buckle 296 may be hinged to the remainder of the wrist band in any
conventional manner and, if desired, pivot bars may be passed
through the endmost apertures for attachment to the wrist band. The
buckle is preferably curved as illustrated at a suitable angle so
as to conform to the wrist of an average wearer with the outermost
surface 318 substantially flush with the outer surface of the wrist
band and the inner edges 320 of the flanges in engagement with the
wearer's wrist when the watch is worn. This assures that the
wearer's wrist will prevent inadvertent opening of the magnet
holder 294 and inadvertent loss of setting magnet 284 although the
holder is normally securely held closed by the snap buttons 312 and
314 and a bias spring (not shown) if desired.
It is apparent from the above that the present invention provides
an improved wristwatch construction and particularly one that is of
simplified, inexpensive construction and one that is easy to
assembly and reliable in operation. The large-scale integrated
circuit chip is completely enclosed in potting compound and the
electrooptic display 68 is preferably coated with a transparent
lacquer or other suitable coating so as to likewise be completely
enclosed and substantially impervious to the elements. Other
components of the watch as illustrated are preferably embedded in a
suitable silicone adhesive which helps attach these components to
the module frame and at the same time resiliently supports them
against shock. The watch provides a rugged impact-resistant,
one-piece, injection molded module frame which houses the entire
module assembly including the cells. The construction provides
durable lead frame connections between the cells and the substrate
and all components are individually sealed before going into
subassemblies or the main assembly. All components or subassemblies
are mounted in silicone rubber for both adherence to the module
frame and high shock resistance. The trimmer capacitor is easily
accessible to adjust the crystal oscillator frequency and the final
assembly of substrate subassembly to module frame subassembly has
only nine simple solder connections. The modular construction
allows the substitution of other subassemblies of variable
components or circuit specifications in place of the original
design and permits, for example, a smaller crystal can as a
replacement, or a smaller substrate may be used without any other
change in the module frame. Simplicity of mounting the module in
the case is provided in that it requires only two case screws and
there is no mechanical or electrical linkage from the watch to the
outside of the watch case.
The invention may be embodied in other specific forms without
departing from the spirit or essential characteristics thereof. The
present embodiment is therefore to be considered in all respects as
illustrative and not restrictive, the scope of the invention being
indicated by the appended claims rather than by the foregoing
description, and all changes which come within the meaning and
range of equivalency of the claims are therefore intended to be
embraced therein.
* * * * *