Shadow or Projection Clocks

© Brooke Clarke 2008

Background
    Ever Ready No. 2225
    This clock patent UK 9462/09
    UK patent 785/19
Disassembly
    Clockwork
Battery Box
Battery
Optics
What Needs to get Fixed
Ceiling Image
Shadow Clock #2
Patents
La Crosse WT-5360U Projection WWVB Clock
Links
UK patent 9462 Fig 4 & 5
Dial Shadow Clock
shadow Clock Overall View
Fig 1   UK patent 9462
Fig 2    Dial End of Shadow Clock
Fig 3   Overall View of Shadow Clock

Background

I was born with a deep interest in how things work and in time (see links below).  Recently flashlights have been under study and I came across a flashlight combined with a clock, hence this web page.  These may have been sold by the UK department store Gamages. 

There are three versions of the shadow projection clock by Alfred Loebl shown in what I think is chronological order.
1.  Ever Ready No. 2225 (1907 catalog) is shown on page 114 of "Flashlights" by Bill Utley.  This version has a built-in clock with a translucent direct reading dial and the same mirror system as the pocket watch version.  For daytime use the mirror lens box is removed and the clock read directly.

Photo courtesy of Bill Utley.

There were a number of Eveready products that used the box which held a three cell battery pack that was most commonly used for UK bicycle lights.
American Eveready Ceiling Shadow Projection Clock
2.  GB190909462 - 1909-07-22 Improvements in or relating to Watches or Clocks - this version with two dials. Fig 4
3. GB190900785 - 1909-08-19 Improvements in or relating to Watches or Clocks - a box to hold a common pocket watch and project it's face on the ceiling. 

To see the watch in the daytime you need to hing down the door and rotate the watch 180 degrees.  Seems like a lot of work.

Seems strange this was the newest version.

Shadow Clock patent 785/09 Fig 1 for Pocket Watch

Fig 5

If you know anything about  shadow projection clocks please let me know.

Disassembly

Someone in the past soldered the lamp holders to the supports and also soldered the support blades to the support posts.  This may have been a way to lower the electrical resistance, but it also acted as a lock preventing normal disassembly.  I've removed the solder between the lamp holders and the support blades thus allowing disassembly.
Shadow Clock with clocl removed
Shadow Clock out of it's case
Fig 6   Clock assembly removed from supports
Fig 7   Clock out of it's case
Note there are two supports on each side (different from the single support on each side shown in Flashlights by Bill Utley).  The two inner supports are connected together electrically and the two outer supports are connected together electrically.  That allows the two lamps to be connected in parallel.  The lamps are marked 3.8 Volts MAZDA.  With a two post design everything must be in series so the juice flows from one support post through it's lamp, through the moving joint, through the clock body, through the other moving joint, through the second lamp and back to the battery switch circuit.  This is a big problem since the moving joints are poor electrical conductors.  A work around would be to put a very flexible jumper wire across the moving joint, but that's not easy.

The lamps and their holders are in fixed positions while the clock assembly can be moved.  This works since the lamps radiate light in all directions.  The lamp holders have a taper on the OD and the support mating part is tapered on it's ID.  This makes for a great connection IF both parts are clean and if they are pressed together while being rotated to seat the tapers.  The person who did the soldering did not understand that there was a taper joint.

Note that the lamp socket (with the taper on it's O.D.) is a machined brass part.  The contact for the center of the lamp is a 3-48 flat head screw insulated with a fiber washer and what appears to be a deformed O-Ring.

Toothed Elevation Adjustment

One of the sheet metal supports has a smooth O.D. on the tapered insert but the other one has 44 teeth cut into it's O.D.  This obviously was not done for decoration, but rather appears to be a way to hold the clock barrel at different angles.  See Fig 6 and Fig 18.

In Fig 6 you can see that one of the screw holes in the clock tube is adjacent to the lamp hole.  A sheet metal finger may have been mounted there that would engage the teeth on the adjacent support.  If you know about this let me know.

Clockwork


Shadow Clock reversed dial
Shadow Clock clockwork
Shadow Clock clockwork
Fig 8   Translucent Reversed Projection dial
Fig 9   Wind & regulate inputs in left bay
escapement & mainspring in center bay
Fig 10   Mainspring ratchet and time gears in right bay

Battery Box


Eveready Shadow Projection Clock Battery Box
Eveready Shadow Projection Clock Battery Box
Fig 11   Eveready Shadow Projection Clock Battery Box
British Eveready Specialties sticker.
The two tabs are contacts for the battery pack.
A prior owner has soldered wires to the tabs
probably because the battery pack was no longer available.

Fig 12   Shown with three "F" cells.
For more on "F" cells see my No. 6 Dry Cell web page which also has some Eveready Pocket Test Meters.

There's perspective at work in this photo so that the BES sticker
could be better seen.  The photo at the left shows the proportions.

Battery


The three F cell batteries have long been obsolete so I'm working on the design of one where the cells can be replaced, i.e. a battery adapter.

The first step has been to come up with a paper doll using ordinary computer paper instead of the USPS Priority Mail box type thin cardboard (0.066").  This is the 5th doll and can be cut from an 8.5 x 11 sheet.  If the cardboard comes in a larger size the box can be made slightly stronger.

The metal is spring tempered phosphor bronze that came from a roll used for motor brushes and will be perfect for this application.

I've removed all the wiring from the battery box so the factory brass tabs can be used to make contact with the three F battery.


Three (3)  F cell Battery Paper doll made from ordinary printer 20# paper.
Fig 13

3 F cell battery using 67# printer paper
This box is much stronger.  Made from 67# printer paper.
The Brass round head fasteners are too thick.  When they
are used the battery does not fit into the shadow clock
battery box.

The paper strip across the top is to hold the contacts
tight aginst the ends of the F cells.  Without it the center
contacts open.  Aluminum foil used for routing the voltage
to the bottom of the battery.
Fig 14

Optics

When just a lens is used the image is reversed.  So for this clock the dial that's going to be projected is printed reversed so it ends up correct.  When a lens and mirror are used the image is correct as projected.  Note that the daytime dial is right side up but the prujection dial is both mirrored and upside down.

The Edmund Optics A48-239 PCX 40 mm dia x 80 EFL, (74.78 BFL) is on order 4 Feb 2008.  The three screws that hold the clock are in slots in the cylindrical housing allowing a small adjustment.  I now (12 feb 2008) this is to allow setting a small gap between the end of the daytime minute shaft and the back of the glass. Also the projection dial could be shimmed to move it closer to the lens, if replacement screws can be found and it it's needed.
Anchor Optics (seconds and low cost division of Edmond Optics)
Edmond Optics -
The lens only provides focusing close to the projector, not the ceiling when installed with the flat towards the clock.  The problem is the "Back" focus distance is a little too short and the lens is on the short side of nominal.  What's needed is a lens that has 80 mm back focus distance.  Have an 84 mm EFL lens on order (12 Feb 2008).

What Needs to get Fixed

Time Savers No. 13427 KD type Hand PullerFig 15 Time Savers No. 13427 KD type Hand Puller
The central post at the left is spring loaded and when fully retracted the distance from the post to the inside of the gripping fingers is about 0.18" but the under side of the hands is more like 0.21".  I'm going to drill a hole in the support block that's a little larger in diameter than the tip which should allow a slightly longer reach.

The hole worked.  It allowed the griping fingers to reach just below the hand and it came off easily.




1 Feb 2008 - Shortly after being imersed in VM&P Naphtha which was in a 4 oz tear top can used for DelMonte mixed fruit which was in a water bath in the ultrasonic cleaner the clock started running.  But when removed from the Naphtha it stopped running.  After oiling with Nye Synthetic Clock Oil 140B it's been running since (2 Feb = a day).  Not running morning of 3 Feb so maybe it needs daily winding?  Ans.  Yes, it took 12 half turns to wind starting with a very weak spring.  Put hands on shadow dial at about noon  3 Feb and at 12:56 the clock is reading 12:56, too soon to set the rate but it's working.  The problem with a wind up clock is you need to wind it every day.  If it's next to  your bed you would wind it each night.
New Projection Dial for Shadow ClockFig 16  This is a new projection clock dial. The three attachment screws are on an isosceles triangle, not an equilateral triangle and none of them is at a cardinal clock point.  Photo shows clock and dial in correct relative orientation.


Printing is on lens side of dial.  Light will come from behind.


Hint:

It's a good idea to set the hands to 12:00 on both dials during installation of the hands.  Trying to read the flipped dial can lead to the two clocks not telling the same time.

The minute hand on the daylight dial has a radius that's bigger than the metal ring that holds the glass.  So the metal ring (and optionally the glass) needs to be removed and installed with the clock work, not separately since that would bend the minute hand unless you can "spring" the ring or get it off center enough to clear the hand.













The Tester for E10 flashlight lamps was made using brass screws that go all the way through the wood so the screw is carrying the current.  That's done here for the round post and will be done for the sheet metal bracket.  The existing wood screws will be replaced with machine screws that do all the way through the wood.  There's a secondary advantage in that the force holding the lamp holder will be increased greatly.  The wood screws loose their grip over time but the through screws and nuts work fine over time, although they may need tightening as the wood shrinks.

The existing wood screw has a round head diameter that's very close to a #2 round head machine screw.  Brass is a much better conductor than stainless steel and will look right at home.
Bypassing the wiring and driving just one lamp at less that it's rating (rated 3.8 volts, drive 3.3 volts) and using a Staples 2 3/4" dia. hand magnifier about 7 1/4" above projection paper dial gives these celing images:  (They look much brighter to you eye.  Just used 5 second exposure).
Shadow Clock celing image 1
Shadow Clock celing image 2
Fig 19
Fig 20

Taken without the brass extension that has the threads for a lens holder so there's some light leakage around the outside of the support rings for the projection dial.   Even though there's a bright spot near 3:00 (and there will also be a bright spot near 9:00 when the second lamp is on) the whole of the clock face is readable.  The photos were taken around 6:40 pm 3 Feb 2008.  The clock is now running about 3 minutes fast since starting it at noon today.  3 min / 400 min = 7.5E-3 stability pretty poor.  The adjust lever was toward "F" so moved it to the center at 7:15 and reset time.

I did paint the chamber below the projection dial white as well as the clock tube in that area to put more light on the dial.  Also paint the inside of the clock nose piece and lens tube black to prevent light from landing on the top of the dial.  Blocking light leaks for the same reason.  A higher technology dial could be made using overhead slide transparancy material and backing it with optical diffusion material, but that's changing the design from what could have been done when the clock was new.

Ceiling Image

Shadow CLock setup for ceiling photo
Shadow Clock with lens and Black & White paint
Fig 21  You can see that the tube above the projection dial is black on the inside and the tube under the lens is also black on the inside.

The hole to the right of the clock looks white to the eye since there's white paint on the clock work in the compartment where the lamps are located (where the big hole is).

The reducing tube on the top of the clock is made in two parts that are soldered together.  If the focal distance needed less than maybe 10 mm adjustment it could be done by melting that solder and sliding the tube up or down.
Fig 22   24 Feb 2008 - The 49 mm dia x 84 mm FL PCX lens is just sitting on top of the tube.  I'm using a bench power supply and a single (not two like in the clock) lamp for light.  Some white paint applied below the projection dial to brighten and get more even illumination also black paint above projection dial to reduce reflections what would lower contrast.  The photo at the left is very close to the feel you get with eye viewing the ceiling.

The line from about a quarter past 1 to about 9:30 is drawn on the ceiling (Sundial page).

The 31 mm hole in the top of the tube acts like a diaphragm to stop down the optics.  The smaller the hole the sharper the image, the larger the hole the brighter the image.  The numbers are a little fuzzy, not because of the focus adjustment, but because of the f/stop.


Shadow Clock #2


Shadow Clock #2 Shadow Clock #2 diagram for 3 D cells to replace the stock three F cells


This clock has the lens, but is missing the two lamp holder assemblies and the winding/setting extension that's accessable when the lens tube is pulled off.  The wire insulation is completly missing in spots.  A prior owner has tack nailed a wooden block in the battery compartment to allow the use of three "D" cells as the power source and included a drawing of their arrangement.

Patents

The clock has markings:
PATENT No.
9462/09

US patent 9462 is for a Trip Hammer.
Inside the box there's a sticker that says:
British Eveready Specialities so maybe this is a UK patent.
Here are the UK patents by Alfred Loebl:

GB190302879 - 1903-12-10 Improvements in or relating to Electrically Operated Clocks.
Electromagnet pulses pendulum when it's swing has decayed.
Also see US patent 759026 Electric Clock
GB190429310 - 1905-02-02 Improvements in or relating to Electrical Dumbbells and similar Appliances for Physical Exercises.
This is now what we call a quack medical device, but at the time they were thought of as medically helpful.
GB190717066 - 1907-10-24 Improvements in or relating to Holders or Fittings for Electric Incandescent Lamps. BEREC
Maybe for Festoon type lamps where there's a contact on each end.
GB190720821 - 1907-12-05 Improvements in or relating to Surgical Lamps and the like. BEREC
Jointed spring used to make headband for surgical lamp that can be folded for storage.
GB190701963 - 1908-01-25 Improvements in Electrical Switches. BEREC
A high current switch with a hand lever for use on electric vehicles.
GB190802676 - 1908-04-09 Improvements in or relating to Holders for Electric Incandescent Lamps. BEREC
Socket for bayonet automotive lamp that has two insulated sockets to accept a two prong plug.
GB190725830 - 1908-05-28 Improvements in or relating to Electric Switches. BEREC
For a single lamp inside a motor car.
GB190909462 - 1909-07-22 Improvements in or relating to Watches or Clocks. Ever Ready Works, Emerald St.
Projection clock with two dials, a normal dial for daytime and a reversed dial for projection.
GB190900785 - 1909-08-19 Improvements in or relating to Watches or Clocks. BEREC
This is a box with a slot in the top that supports a common pocket watch allowing it to be moved for focusing.  Two side mounted lamps illuminate the watch and a mirror turns the image toward the ceiling and a lens forms a real image.
GB190929238 Improvements in or relating to the Warming of Internal Combustion Motors.
        An 8 candle power lamp (probably in the socket of 17066 above) is mounted in a metal can and placed in the engine compartment to keep it warh.

Shadow or Projection Clock Patents

This is an attempt to learn more about shadow projection clocks.  The main use seems to have been as an advertisement method.
Patent Class Numbers
368 Horology
    /62 Cronological
    /76 With mechanical or electromechanical driven display
    /79 Optical
    /234
40 Card, Picture or sign Exhibiting (Advertizing)

759026 Electric Clock, Herbert Scott & Alfred Loebl, May 3, 1904, 368/166 ; 368/134; 368/179; 368/204; 368/316 - electrically-operated clocks, and has particular reference to clocks in which a pendulum, balance-wheel, or torsion-wheel receives an impulse from an electromagnet only when the amplitude or extent of its swing or movement is diminished.

740433 Night Light, Friedrich Hirth, Oct 6 1903, 368/227 ; 353/40; 362/253; 40/560 - when remote switch is closed projects clock hands on ceiling
812105 Advertizing Projecting Apparatus, FEKDINAND WETZLEE, Feb 6, 1906, 368/76 ; 368/227- projects time and ad
813836 Shadow-Clock, RICHARD BARTHOLOMEW SMITH, Feb 27 1906, 368/79 ; 40/560 - projects both time and advertizments
1097310 Automatic Annunciator, Genter, Jun 19 1914, 368/223 ; 368/238 - projects slides & time
1137512 Advertizing Clock , H. MILLER Apr 27 1915, 353/40 ; 368/223- project time and advertizing message
1147501 Automatic Annunciator, Genter, Jul 20, 1915, 368/234 ; 362/268 - projects slides & time
1172844 Stereoptican Advertixing Clock, ABRAHAM STEINBERG (Kineto Machine Co), Feb 22, 1916, 368/234 - projects time and ads
1275791 Clock Mechanism, Thereault, Aug 13 1918,368/42 ; 40/474; 40/496; 968/384 - projects time and changes dial images
1579880 Shadow Projecting Apparatus, Meissner, Apr 6 1926,  368/79 - for use outdoors or in a large indoor room
1667210 Advertizing Device, KARL OSCAB LEON, Apr 24, 1928, 368/67 - the ads don't conflict with the time display
1913870 Advertizing and the Like Device, G. BRIGGS, Jun 13, 1933, 368/41 ; 353/110 - rear projection system with film strip of ads and clock
1938417 Clock Illuminating Mechanism, Joseph C. Curran, Dec 5, 1933, 368/79 ; 116/DIG.29; 116/DIG.36; 368/234; 40/444; 968/490 - uses 12 lamps
2150036 Clock, J. J. PARIS, Mar 7, 1939, 368/79 ; 246/1C; 968/216 - alarm clock turns on projected ceiling image when alarm rings
2201376 Clock, Leendert Prins, May 21 1940, 368/79 ; 968/216 -
2243759 Clock, Joseph Maluo, May 27, 1941, 368/220 ; 968/216; D10/126 - designed to be used with conventional projector
2290811 Projector for Time Indications, Nassoit, Jul 21 1942, 368/76 ; 353/40; 368/227; 968/216 - single film strip moves once per minute
2351238 Display Device, Max M. Teuber, Jun 13 1944, 368/223 ; 40/560 - projects both time and ads
2486425 Watch Dial Projecting Device using Reflected Light, S.  Loewe, Nov 1 1949, 353/40 ; 362/26; 368/227-
References:
813836 see above
835431Projector for Pathalogical Work, Nov 6, 1906, Nov 6, 1906, 353/66 - reflected light projector
1074260 Device for Projecting Images of Temperature Indicators, GEORGE M. GUEBBANT, Sep 30, 1913, 353/40 ; 33/355R -
lamp, collimator, needle pointer and projection lens
1616747 Picture Projecting Device, AUBREY DE VERB HARNETT, Feb 8 1927, 353/66 -
images arranged around the edge of a book with text in the center.  Projector moved around edge
2201376 Clock, Leendert Prins, May 21 1940, 368/79 ; 968/216 - very similar to my projection clock in layout, except has reflector
2351238 see above
2502985 Clock, Bernard J. Paulson, Apr 4 1950, 368/79 ; 116/286; 116/DIG.6; 368/234; 968/213-
a rear projection clock where the hour digits and minute hand is  projected onto it's face
Calls:
1887479 Illuminated Clock - clock with light- not projection
1950189 Timepiece - different time zones- not projection
2009209 Illuminated Measuring Device - edge lit hands - not projection
2380171 Time Indicating Mechanism - rear projection of hour digits
2652745 Direct Reading Projection Clock Apparatus, Francis J. Quinn, Sep 22 1953, 368/79 ; 352/126; 352/97; 353/35; 40/472; 968/216-
uses two loops of movie film, one with the hours and the other with the minutes
Calls:
1097310 Automatic Annunciator, Genter
1147501 Automatic Annunciator, Genter
1290947 Advertizing Projecting Device - film strip projector, not clock
1523767 Means for Displaying Quotations or the like - an opaque projector, not clock
1479880 ?
1580286 Station Indicator - in railway cars film strip projector, not clock
2025361 Advertizing Device - film strip projector
2078936 Stock Quotation Projecting Machine - opaque projector not clock
2351238 Display Device, Max M. Teuber
2694338 Clock Face Projecting Device, Isaac Moultry, Nov 16 1954, 368/69 ; 353/85; 968/216 -
has remote push button switch to turn on the lamp
Calls:
740433 Night Light, Friedrich Hirth, Oct 6 1903
778891 Magic Lantern w/electric lamp - not clock
813836 Shadow-Clock, RICHARD BARTHOLOMEW SMITH
1032160 Station Indicating Device for the outside sign on street cars - not clock
1137512 Advertizing Clock , H. MILLER
1153110 View-Changind Device - film strip projector with remote advance button - not clock
1292005 Projector - a collimated light source to which a camera is attached making a projector, not clock
1992776 Projector - for childern's viewgraph disks - not clock
2201376 Clock, Leendert Prins
2351238 Display Device, Max M. Teuber
2486425 Watch Dial Projecting Device using Reflected Light, S.  Loewe
2726571 Shadow Image Clock Projecting Device, Henry K. Chang, Dec 13 1955, 368/79 ; 40/560; 968/216 -
Calls:
457694 Magic Lantern uses clockwork to time projection of ads and train stations
812105 Advertizing Projecting Apparatus, FEKDINAND WETZLEE
813836 Shadow-Clock, RICHARD BARTHOLOMEW SMITH
877041 Projection Apparatus for opaque or transparent subjects - not clock
1053650 Exhibition Device for stereoptican images - not clock
1172844 Stereoptican Advertizing Clock, ABRAHAM STEINBERG (Kineto Machine Co)
1913870 Advertizing and the Like Device, G. BRIGGS
2195425 Projector, Opaque - not clock
2201376 Clock, Leendert Prins
2351238 Display Device, Max M. Teuber
2834250 Projecting Clocks Provided with Rotating Dials, E. STEFANI, May 13 1958, 368/234 ; 235/61PK; 353/40; 40/560; 968/216 -
projects only an analog hour dial, designed to be built into furniture
Calls:
1619096 rear projection of ads - not clock
2191045 Speed Indicator for cars - not clock
2351238 Display Device, Max M. Teuber
2471800 Shadow Image Projection Indicating Apparatus - an electrical meter - not clock
2486425 Watch Dial Projecting Device using Reflected Light, S.  Loewe
2579806 Projecting Speed Indicator - car speedometer - not clock
2641159 Vehicle Indicator Optical Projection Device - car speedometer - not clock
2641160 Vehicle Indicator Optical Projection Device - car speedometer - not clock
2694338 Clock Face Projecting Device, Isaac Moultry
2875668 Projector for Time Indications, G. Stuart Mckenzie, Mar 3 1959,368/76 ; 368/227; 40/472; 968/216 -
analog line powered clock has two film strips, one for hours and one for minutes both expressed in digits his and hers light buttons
Calls:
 1147501 Automatic Annunciator, JACOB H. GENTER
2078936 Stock Quotation Projecting Machine - opaque projector not clock
2425704 Power Driven Intermittent Strip Film Mechanism  - not clock
2486425 Watch Dial Projecting Device using Reflected Light, S.  Loewe
2652745 Direct Reading Projection Clock Apparatus, Francis J. Quinn
2834250 Projecting Clocks Provided with Rotating Dials, E. STEFANI
3136210 Apparatus for Shadow Projection of Clock Dial, Charles A. Barrett, Jun 9 1964, 368/79 ; 353/40; 353/85; 968/216
dial pivots so it can be positioned facing out for normal reading  or facing light source for projection, Calls:
740433 Night Light, Friedrich Hirth, Oct 6 1903
1578607 Watch - looks like a folding travel clock - not projection
1645633 Watch - looks like a folding travel clock - not projection
2243759 Clock, Joseph Maluo
2358422 Combined Bed Reading Lamp and Clock - not projection
2694338 Clock Face Projecting Device, Isaac Moultry
2726571 Shadow Image Clock Projecting Device, Henry K. Chang
2834250 Projecting Clocks Provided with Rotating Dials, E. STEFANI
3179003 Horologe with Time Indication Projected on Screen, Clement R. Toinpson (Zenith Radio Corp), Apr 20, 1965,
 368/79 ; 116/DIG.29; 368/227; 368/234; 968/216; D14/170-
 projected hour digits in clock radio conventional azimuth minutes indication.
Calls:
1275791 Clock Mechanism, Thereault
2040421 Numeral Clock - flipping card type - not projection
2886942 Indicating Device for Watches - not projection
339220 Night-Clock, Apr 6, 1886, 368/67 ; 362/29 - clock drives glass cylinder with candle in center
3620004 Time Indicating Device of the Direct Read-off type, F. H. MARZ (Bunker-Ramo Corp), Nov 16 1971, 368/224 ; 368/185; 368/228; 968/216-
Filmstrip projector which advances once a minute.  Continous loop of fild good for 12 or 24 hours at one frame per minute
Calls:
2652745 Direct Reading Projection Clock Apparatus, Francis J. Quinn
1667210 Advertizing Device, KARL OSCAB LEON
3673787 Digital Clock Mechanism, Radoslav Kovacevic, Jul 4 1972, 368/79 ; 353/40; 353/74; 368/220; 968/216; 968/553; 968/577
a rear projection clock showing hh:mm:ss based on an analog clock using gears
Calls:
1218607 Stereoptican Advertizing Clock, GEORGE WILLENS, Mar 6, 1917, 368/124 ; 368/234 -
1137512 Advertizing Clock , H. MILLER
2351238 Display Device, Max M. Teuber
2486425 Watch Dial Projecting Device using Reflected Light, S.  Loewe
2694338 Clock Face Projecting Device, Isaac Moultry
2834250 Projecting Clocks Provided with Rotating Dials, E. STEFANI
3136210 Apparatus for Shadow Projection of Clock Dial, Charles A. Barrett
3179003 Horologe with Time Indication Projected on Screen, Clement R. Toinpson (Zenith Radio Corp)
2875668 Projector for Time Indications, G. Stuart Mckenzie
3439492 Chromoclock, G. F. GRAVENSON - not clock random color generator
2875668 Projector for Time Indications, G. Stuart Mckenzie
3783603 Time Indication, Paul Himmelsbach, Jan 8 1974, 368/82 ; 368/234; 968/216 -
uses two overlapping disks to project HH and MM, can be 24 hours. Rear projection.
Calls:
3673787 Digital Clock Mechanism, Radoslav Kovacevic
2502985 Clock, Bernard J. Paulson
2834250 Projecting Clocks Provided with Rotating Dials, E. STEFANI
3179003 Horologe with Time Indication Projected on Screen, Clement R. Toinpson (Zenith Radio Corp)
D345308 Design for Clock, Hiromi Kanai, Mar 22 1994, D10/26
Calls:
740433 Night Light, Friedrich Hirth, Oct 6 1903
813836 Shadow-Clock, RICHARD BARTHOLOMEW SMITH
2290811 Projector for Time Indications, Nassoit
2486425 Watch Dial Projecting Device using Reflected Light, S.  Loewe
2652745 Direct Reading Projection Clock Apparatus, Francis J. Quinn
2726571 Shadow Image Clock Projecting Device, Henry K. Chang
2875668 Projector for Time Indications, G. Stuart Mckenzie
3136210 Apparatus for Shadow Projection of Clock Dial, Charles A. Barrett

Other Patents 

693953 Geographical Clock, Charles E. Davis , Feb 25 1902, 368/27 ; 180/90; 362/29 -
24 hour clock showing light and dark with city names
700496 Electric Time Alarm, Conrad Hubert, May 20 1902, 368/259 ; 200/35R; 315/360; 362/253; 368/256 -
700497 Electric Battery, Conrad Hubert, May 20 1902, 429/133 ; 439/816 -
a cylindrical cell with a metal ring at the top so that both contacts are on the same end.  The Electric Time Alarm uses three of them each in a wooden compartment with two springs to make contact.
704446 Watch Dial Illuminator, Frederick M. Durkee, Jul 8, 1902, 368/277 ; 362/23; 368/223 - cylinder holds battery, hangs on wall with flashlight bulb above watch, when button at end of cord is pressed you can see watch.  Button looks the same as this one.
815072 Electric Alarm Clock, Augusta Y. Darche, Mar 13, 1906, 368/258 - uses first generation No. 6 dry cell and stand D37091.
D37091 Stand for Portable Electric Alarm Clocks, Augusta Y. Darche, Aug 16 1904, D10/128 ; D10/1; D10/23 -
2466312 Transparent Disk Clock, Ralph M. Heintz, Apr 5 1949, 368/77 ; 368/234; 968/395 -
transparent disks for hours, minutes and 1 to 12.
712112 Illuminated Watch Box, CAROLUS ARNOLD, Oct 28 1902, 362/155 ; 132/288; 362/109; 368/276 -
Box with light in lid, battery in bottom and switch connected with the latch button
721205 Electric Time Switch, ALBERT W. LAUTER, Feb 24, 1903, -
when alarm clock goes off it turns on a flashlight lamp in front of the clock.
740433 Night Light, Friedrich Hirth, Oct 6 1903 (see above)
750787 Clock Case, Aaron D. Blodget, Jan 26, 1904, 368/291 ; 362/30 - Illuminated Tower Clock
835762 Watch Stand, M. Koller, Nov 13 1906, 368/316 ; 362/23 - a stand allows a watch to hand and avove is a pocket flash light
1101429 Automatic Annunciator, Genter, May 1914, 368/223 ; 362/268; 362/293; 362/308; 362/812; 368/238; 40/473 -
projects time & ads (see above)
1106807 Pendulum Lamp for Clocks, CHRISTIAN B. HANSON, Aug 11, 1914, 368/67 ; 362/234; 368/88 -
pendulum has a constant burning lamp and the clock has lamps that blink in beat with the pendulum.
1135228 Clock, Leverett F. Viner, Apr 13, 1915, 368/88 ; 116/286; 362/29; 968/213 - backlighted dial for clock in floor
1233559 Reminder Clock, Augusta Y. Darche, Jul 17, 1917, 200/37R ; 368/250 - a pin is inserted ( 15 minute steps) to set alarm time
1271735 Illuminated Watch Holder, BENJAMIN F. LOCKWOOD, Jul 9 1918, 362/103 ; 116/DIG.36; 362/23; 368/10- on the back of a glove
1515135 Illuminated Globe, A. S. ALEXANDER, Nov 11 1924, 434/143 ; 362/269; 368/24; 434/145; D26/94 -
Not just day and night, but also season of the year (manual setting)
1656029 Advertizing Device, G. WILLENS, Jan 10, 1928, 40/575 ; 362/23; 368/227; 40/716; 40/728; 968/216; 968/393 -
clock hands are projected as shadows (no expensive lens) and ad in paper form in window.
1750505 Astronomical Clock, M.N. Bulka, Mar 11 1930, 368/16 ; 362/132; 362/809; 368/37; 434/293 -
Shows relationship between Earth, Moon and Sun using a lamp and gears
1760253 Advertizing Clock Dial and Means of Illuminating the same, Parrish, May 27 1930,
 40/546 ; 180/90; 246/1C; 362/29; 368/232; 368/239; 968/213; 968/392 - radium painted clock hands are illuminated by a nearby light which is filtered - use in theaters
1959601 Chronological Instrument, Herman E. Schulse (Uniclox Corp), May 22 1934, 368/24 ; 362/809; 368/185; 368/28; 434/143; 434/145; 968/178; 968/210; D19/61 - illuminated globe that tracks both time and date. 
1994950 Illuminated Dial, Charles William Hoffritx, Mar 19 1935, 362/23 ; 362/216; 368/226; 368/232; 968/213- hidden Neon tube illuminated hands and numbers on black dial
2045798 Combined Alarm Clock and Light, Purvis, Jun 30 1936, 368/256 ; 362/253; 968/613- uses line powered lamp
2099518  Globe Chronomoter, G. W. Haslett, Nov 16, 1937, 368/24 ; 362/809; 434/142; 968/169 -
displays time but not sun's shadow or effect of seasons
2290278 Illluminated Indicating Device, J.J. Failla, Jul 21 1942,
 368/234 ; 116/287; 116/DIG.5; 362/26; 362/559; 362/576; 368/238; 73/866.1; 968/214
uses light pipe
2290750 lluminated Clock, P. J. Howe & C.H. Wyss (Western Union Telegraph Co), Jul 21, 1942, 368/234 ; 362/216; 73/431 - to fit in small space, probably so can be added to the existing Self Winding Clock Co "Western Union" clocks.

La Crosse WT-5360U Projection WWVB Clock

La Crosse WT-5360U Projection Atomic WWVB Clock

The price from Klock Kit was much lower (< $20) than the La Crosse price.

This is a modern "Atomic" clock that sets itself using the WWVB 60 kHz radio transmissions.  The projector is on a swivel and so can be aimed at any angle.  As long as the AC adapter is powering the clock the projector is active.  If the power fails the two AA batteries keep the clock operating, but the projector only turns on when a button is pressed then times out.  This allows the clock to be read at night just by looking at the projected image, i.e. you don't need to be near the clock or press any buttons.

I initially had the clock body turned 90 deg CCW from how it's shown above and with the projector pointing almost straight up.  But after leaving it overnight it still had not set itself.  Then it was turned 90 degrees to the position shown above but this required tilting the projector down to about 45 degrees (the camera is pointing down at the projector to see some of the red light).  The button with the four arrows rotates the image about the projection axis in four steps so you can get the bottom of the numbers to be on the bottom from where you view the image.
Note
The latest manual says install the batteries and DO NOT PRESS ANY BUTTONS FOR 15 MINUTES.  When first trying to get the clock to set itself I tried removing the batteries to start over, but after that it would not work properly.  The batteries are installed with their axis parallel and arranged head to tail.  So I removed the batteries then using the scissors on a classic Rambler Swiss Army knife shorted the terminals at one end of the battery compartment then shorted the terminals at the other end of the compartment.  Now when the batteries were installed the clock beeped and behaved as per the manual.

Note that loop antennas have a deep null and if the null is pointed to WWVB the clock will not work at all.   This is easily seen using a raw WWVB receiver like the CMMR-6P-60..

Unlike other "Atomic" clocks, this one allows you to manually set the time and date as well as any of 24 time zones.  This would allow it being used where WWVB or WWVBH can not be heard.

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page created 12 Jan 2008.