Bifora 934

Description

One of the standard movements from the german Bidlingmaier GmbH from Schwäbisch Gmünd, was the Bifora 934 with a diameter of 9 3/4 lignes (hence the caliber number), an pallet lever movement with a pillar construction.

Its construction is classical and simple: The balance (here in its best version as glucydur screw balance), which is beared in two inhose Bishock shock protection systems, controls a conventional pallet lever movement, which contains a decentral second at "6".

The hairspring is fix connected to the balance cock and regulated in its effective length by a long regulator arm with scale.

main plate

The gear construction is classical-conventional with escapement wheel, fourth wheel, third wheel and minute wheel.

The latter gets its energy from the mainspring barrel, which contains its click spring on the dial side.

side view of the pillar construction

On the side view, you see the pillar construction, which was cheaper than using massive plates, but results in a larger thickness.

dial side view

On the dial side, there's the rocking bar winding mechanism and the click spring, which is very well made. You also see the rather large bearing rubies.

Technical data

Manufacturer	Bifora
Caliber	934
Number of jewels	17
Escapement	Anchor with pallets
Balance	Glucydur screw balance
Shock protection(s)	Bidlingmaier (Bifora)
Balance cock direction	clockwise
Hairspring stud	fixed
Regulator type	Long regulator arm
Movement construction	Fork Escapement wheel, Fourth wheel, Third wheel, Center wheel Mainspring barrel
Construction type	pillar construction
Bridge shape	Axe, 4 gears
Winding mechanism	Rocking bar
Setting lever spring	4 holes
Features	s
Functions	Hour, minute, small second
Beats per hour	18000
Size	9³/₄''' (measured: 21,0 mm)
Image in Flume Werksucher	1957 35

Factsheet

Timegrapher output

The specimen shown here, was completely gummed and cleaned and olied afterwards.

Nevertheless, the timegrapher outputs are very unsteady, especially in the vertical positions. And there, the positions "12 up" and "9 up" are pretty worse; the reasons can be a badly poised balance or a bent balance staff.