TIMEX model 87 Electronic Calendar Watch Service Manual

Removing the Movement from the Case

The initial step in removing the movement from the case involves taking out the energy cell. To prevent damage to the watch case, the energy cell cover should only be opened at the designated spot marked with an arrow and the words "lift here" on the caseback. It is advisable to check the energy cell's voltage; any cell with less than 1.5 volts, or one that has been in service for over a year, should be replaced. Avoid short-circuiting the cell by preventing metallic connections between the outer case and the cell's negative pole, as this can shorten the cell's lifespan.

Next, remove the crystal using a Timex crystal lift or a standard crystal lift tool. The movement can then be extracted from the front of the case. Note the locating notch in the bezel seat (labeled A) and the corresponding key on the balance bridge (labeled B).

The caseback is fixed with epoxy resin and should not be removed.

The crown set wheel remains attached to the caseback. An automatic coupling device links it to the setting stem when the movement is reinstalled in the case.

To remove the crown set wheel, follow these steps:

• Lift the crown set wheel to the "stop" position.
• Using tweezers, spread the retaining spring open and push the crown set wheel down through the rear of the case.
• If necessary, the retaining spring and gasket can also be removed.

Diagrams illustrate the disassembly process. The first shows the energy cell cover, energy cell, and negative pole. The second depicts removing the crystal using a lift tool. A third shows the caseback with a retaining spring, gasket, and crown set wheel, detailing the procedure to remove the crown set wheel.

Examining Movement Function and Energy Cell Assembly

To examine the movement's function, place it on a suitable movement ring and secure the energy cell with an energy cell retaining spring. This specific spring is available upon request from the Timex Material Sales Division.

To assemble the energy cell retaining spring:

• Loosen screws A and B.
• Lift the switch insulation using a screwdriver.
• Insert the energy cell retaining spring between the switch insulation and the hand setting spring.
• Finally, tighten screws A and B.
• Ensure one end of the energy cell retaining spring depresses the stopping spring, allowing the balance to turn freely.

The negative pole of the energy cell must connect to the connection spring (No. 4160 on the exploded view). Current from the negative pole flows through this spring to the connection yoke of the electronic circuit. These parts are insulated from the rest of the movement. The positive pole of the energy cell contacts the energy cell retaining spring, directing current to plate No. 100. It is crucial to avoid creating a metallic connection between insulated and uninsulated parts of the movement, as this short circuit could reduce the energy cell's life.

Illustrations show the movement clamped on a ring with an energy cell retaining spring. One diagram details the assembly of the energy cell retaining spring, showing screws A and B, switch insulation, and the spring's placement. Another diagram highlights the connection of the energy cell's negative pole to the connection spring (4160) and the positive pole to the energy cell retaining spring, emphasizing insulation.

Electrical Impulses and Balance Bridge Removal

The electronic circuit transfers electrical impulses to mechanical driving impulses for the balance, similar to the Model 84. Impulse current flows through the balance drive coil. The magnetic south pole of the coil is attracted by the permanent magnet's north pole and repulsed by its south pole. The electronic circuit is triggered by the voltage induced in the balance coil as it moves through the permanent magnet system.

The permanent magnet system, along with the shunt bridge, can be rotated out of position to expose the balance and hairspring. This is done by removing one screw (C). For complete removal, both screws (C) can be removed.

After removing the permanent magnet system, the balance bridge and balance can be detached. Screw (D), used for adjusting the balance's endshake, is secured with epoxy. Before disassembling the balance bridge, screw (E), which connects the electronic circuit to the balance bridge, must be removed. Additionally, the bronze hairspring must be detached by loosening screw (F). The hairspring stud can be pressed out of the balance bridge to separate the bridge and balance. The bronze hairspring clamping block is insulated from the balance bridge. An insulating washer is located beneath the screw holding this block; ensure it is in place during reassembly to prevent short circuits. The crown set wheel stem (G) also serves as the staff for the minute wheel and connects to the crown set wheel on the caseback via a clutch device.

A circuit diagram is provided, labeling components such as Battery, T1, T2, resistors (R3-R6), capacitor (C7), Stop-Switch, and Coil.

Diagrams show the permanent magnet system and shunt bridge, indicating screw (C) for removal. It also shows the balance bridge and balance, with screws (D), (E), and (F) for adjustment and removal, and a hairspring clamping block.

Crown Set Wheel Operation and Setting Spring Adjustment

Illustration 1 shows the crown set wheel in its running position. The clutch disc is disengaged from the stem, and the setting spring is depressed. In this state, the projection on the setting spring is clear of the balance's stopping finger. The nose (H) of the stop switch must touch the rivet (J) of the setting spring.

Illustration 2 depicts the crown set wheel in the set position. The clutch disc now engages the square portion of the stem, coupling the stem and crown set wheel, which allows the hands to be set. This position also causes the setting spring to move upwards, contacting the balance's stopping finger and halting the balance. The nose (H) of the stop switch must be clear of the setting spring's rivet (J), thereby interrupting the electronic circuit's starting current.

For setting spring adjustment, follow this procedure:

• Move the crown set wheel upwards until the clutch disc is just out of engagement with the set stem's square portion (as shown in Illustration 3). The clutch disc should rest against the bottom of the stem's square portion.
• In this position, the projection on the setting spring must contact the stopping finger on the balance by the amount indicated.
• When the crown set wheel is pulled into the set position (Illustration 2), the stopping finger on the balance must be in full contact with the setting spring's projection.
• To make this adjustment, bend the setting spring in the area marked (K).
• Ensure the stop switch nose (H) is clear of the setting spring's rivet (J) by at least 1/2 to 1-1/2 times the thickness of the setting spring. If necessary, adjust this clearance by bending the setting spring in area (L).

Three illustrations detail the operation of the crown set wheel. Illustration 1 shows the running position with the clutch disc disengaged and the setting spring depressed. Illustration 2 shows the set position with the clutch disc engaged, allowing hand setting and stopping the balance. Illustration 3 details the adjustment procedure for the setting spring, showing the clutch disc just out of engagement and the projection on the setting spring contacting the stopping finger.

Removing Clutch Mechanism and Electronic Circuitry

To remove the clutch mechanism from the movement, first lift the plastic sleeve from the stem using tweezers. Place your finger on top of the plastic sleeve during this operation to prevent its loss. Next, remove the clutch disc. Then, remove screw "A" and the setting spring. The electronic circuitry can now be detached by removing screws "B" and "M". Screws at positions "B" and "M" are fitted with insulating washers that must be correctly repositioned during reassembly to avoid short circuits. The screw at position "M" should also be removed. Lift the circuit base, as shown, and turn it in the direction of the arrow until the stop switch clears the train bridge. Exercise care to prevent damage to the stop switch.

A diagram illustrates the removal of the clutch mechanism. It shows lifting the plastic sleeve from the crown set wheel stem, removing the clutch disc, screw 'A', and setting spring. The electronic circuitry is then removed by unscrewing 'B' and 'M', noting the insulating washers. The circuit base is lifted and turned to clear the train bridge.

Gear Train Action

The gear train functions in a standard manner. In Illustration 1, as the balance moves counterclockwise, it moves the indexing lever (1) to the left. This lever has a steel "D" shaped pin that advances the index wheel (2) by one tooth. After advancing the index wheel, the indexing lever rests against the banking pin (3). The tip of one tooth on the index wheel is attracted and held by the magnet (4). Because the index wheel is magnetically fixed, the "D" shaped pin on the index lever cannot move out of position between the index wheel teeth on its own.

In Illustration 2, when the balance moves clockwise, it shifts the index lever to the right. The "D" shaped pin then moves the index wheel backward slightly until it clears the index wheel's tooth. The index lever rests against the banking pin (3) and is held by magnetic attraction between the magnet (4) and the "D" shaped pin. The instant the "D" shaped pin clears an index wheel tooth, magnetic attraction retracts the wheel to its original position, ready for another one-tooth advancement during the next counterclockwise balance rotation. After the index wheel advances three teeth, one tooth of the two-toothed pinion attached to it engages the sweep second wheel, rotating it forward by one tooth. This single tooth rotation of the sweep second wheel, assisted by the click (5), creates the one-second "jump" of the sweep second hand. The safety finger (6) ensures that the sweep second wheel indexes by only one tooth at a time. The click spring must be locked as illustrated. Pre-tension of the click spring should be approximately 2 to 2½ times the diameter of the locking pin.

Two illustrations depict the gear train action. Illustration 1 shows the indexing lever (1) moving the index wheel (2) forward one tooth via a 'D' shaped pin, resting against a banking pin (3), with the index wheel held by a magnet (4). Illustration 2 shows the balance moving clockwise, retracting the index lever and wheel slightly, then being re-indexed. It also shows the two-toothed pinion engaging the sweep second wheel, driven by a click (5) and safety finger (6).

These pages provide labeled diagrams of the gear train components shown in Illustrations 1 and 2 on page 9, identifying parts like Index Wheel (②), Indexing Lever (①), Magnet (④), Banking Pin (③), Click (⑤), Minute Wheel, Safety Finger (⑥), Third Wheel, Sweep Second Wheel, Center Wheel, and Two Tooth Pinion.

Third Wheel Assembly and Arresting Magnet

The remainder of the gear train operates normally. The sweep second wheel pinion drives the third wheel, which in turn rotates the center wheel carrying the minute hand. The center wheel's teeth mesh with the minute wheel. The minute wheel's staff extends to the dial side and carries the minute pinion.

Dial train friction is managed by the third wheel assembly, with a friction washer placed between the third wheel pinion and the third wheel. Proper lubrication of this assembly is crucial after cleaning.

The index magnet can be removed to inspect the train. During magnet removal, ensure the index lever is positioned as shown in Illustration 1 on page 87.9. When reassembling the hands, it is important to support the sweep second wheel assembly at its pivot to prevent damage.

A diagram of the Third Wheel Assembly shows the third wheel, friction washer, and third wheel pinion, with an indication to lubricate. Another diagram shows the arresting magnet and the index lever in position for its removal.

Cleaning

The movement, including the electronic circuit, can be cleaned using standard watch cleaning and rinsing solutions. The balance must be cleaned separately to protect the coil. Do not clean the energy cell with any liquid; if necessary, wipe it with a dry cloth only.

After cleaning, carefully remove any particles adhering to the magnet before assembly. A piece of scotch tape rolled to a point can be useful for particle removal. This method should not be used when the movement is assembled, as it risks severing the balance coil's lead wires. Ensure all other movement parts are free of particles, especially steel or nickel, which could be attracted by the magnet. The watch should not be demagnetized.

Lubrication

The movement should be re-oiled using only high-grade watch oils. The oil used in factory assembly is Elgin M 56 b. Under no circumstances should oil or grease containing silicone be used.

The specific points requiring lubrication are:

• The jewel bearings and pivots of the train wheels and balance.
• The minute wheel and set stem bearing surfaces.
• The steel "D" shaped pin on the index lever.
• The surface of the click that contacts the sweep second wheel.
• The third wheel assembly, as indicated on page 87.9.
• The pipe of the crown set wheel, ensuring lubricant seeps down to the surrounding rubber waterproofing gasket.

Never lubricate the connection point between the stop switch and the setting spring.

Timing

For optimal performance of the Timex electric watch, the hairspring should not vibrate between the regulator's pin and key. The outer edge of the hairspring should maintain light, permanent contact with the inner edge of the regulator key. Ensure both hairsprings have adequate clearance from all other movement parts, such as the balance bridge and the upper shunt of the driving magnet.