Ronda 7115

 
Ronda 7115

Ronda 7115

Description

The Ronda 7115 is a rather late and simple constructed movement from Ronda, which has got many similiarities with compareable Timex movements.

base plate

base plate

It is already noticeable on the base plate of this pillar construction, that it is not is completely round, but has got large cutouts in the area of the balance and the mainspring barrel.

Much more interesting is, that you see red - a lot, and that it not only comes from almost all the important bearings, using rubies, you also see four read blind jewels with no function at all. Interestingly, the center seconds bearing is not jewel beared!

gear train

gear train

The gear train construction reminds of that of a Roskopf movement, since also here, the hands are driven by the mainspring barrel.

Nevertheless, the common four gears are used: Large driving wheel (driven by the mainspring barrel), small driving wheel, center seconds wheel and escape wheel.

side view of the gear train

side view of the gear train

The anular balance with its two slanted legs should be resistant agains shocks, so that it doesn’t need to run in shock-protection bearings. Of course, this doesn’t really work with the fine pivots and so the specimen in the archive suffers from broven balance wheel pivots.

As escapement a pin pallet escapement with steel pins is used.

With a beating frequency of 18000 A/h, which movements uses the same rate as a standard pin pallet movement.

empty dial side

empty dial side

At one and seven o’clock position, you can spot the four blind jewels.

You can also see the rocking bar keyless works with a very well made ratchet on the dial side.

Since the mainspring barrel is used to drive the hands, the power transmission happens with a double cannon pinion, whose lower gear engages with the mainspring barrel and is connected with a slip clutch with the upper part, which carries the minute hand and engages with the change wheel.

cannon pinion

cannon pinion

The Ronda 7115 is a simple date indication mechanism. With the help of a star wheel at 12 o’clock, whose one pin is a bit longer than the others and advances the date ring. The switching process takes place between 11:25 pm and midnight.

calendar mechanism

calendar mechanism

This very simple calendar mechanism offers no quickset possibility, which means, that you have to “crank” a lot to set the correct date.

yet uncovered calender mechanism

yet uncovered calender mechanism

The calendar mechanism is normally covered by a flat plate with a recess to insert a spring.

Ronda 7115: Dial side

Ronda 7115: Dial side

The Ronda 7115 is a pretty odd movement. Its very high number of 21 jewels should indicate a quality movement, but in reality, it is just a pin lever movement with 14 functional jewels. Nevertheless, that’s 13 or 14 jewels more, than most other pin lever movements can offer.

Technical data

Manufacturer:Ronda
Caliber:7115
Size:11 1/2''' (measured: 25,5mm)
A/h:18000
Number of jewels:21
Escapement:Pin lever
Balance types: Nickel anular balance (two slanted legs)
Shock protection(s): none
Balance bearing / direction hairspring:Counterclockwise
Moveable stud:yes
Adjust mechanism:Hairspring key
Construction:
  • lever
  • escape wheel, seconds wheel, third wheel, large driving wheel
  • mainspring barrel
Construction type:pillar construction
Winding mechanism:rocking bar winding system
Setting lever spring:4 hole(s)
Features:
  • SCD (direct center seconds)
  • QG (date indication (aperture))
Literature: Flume: K3 -
Inventory number:20042

Usage gallery

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