Part 12 (2/2)

_G_--Upper Plug

_H_--Lower Plug

_g_--Entrance Lip of Cylinder

_h_--Exit Lip of Cylinder

_c_--Banking Slot

_C_--Tooth

_D_--U arm

_E_--Stalk of Pillar

_I_--U space

_l_--Point of Tooth

_k_--Heel of Tooth

The cylinder escapee of each tooth; that is, one on the outside of the cylinder and one on the inside of the shell As we shall show later on, the cylinder escapement is the only positively dead-beat escapeht recoil during the process of escaping

When the tooth of a cylinder escape wheel while perfor its functions, strikes the cylinder shell, it rests dead on the outer or inner surface of the half shell until the action of the balance spring has brought the lip of the cylinder so that the impulse face of the tooth commences to impart122]

[Illustration: Fig 123]

[Illustration: Fig 124]

[Illustration: Fig 125]

[Illustration: Fig 126]

[Illustration: Fig 127]

[Illustration: Fig 128]

Most writers on horological matters term this act the ”lift,” which name was no doubt acquired when escapements were chiefly confined to penduluht on the126 that if the tooth _C_ is released or escapes from the inside of the half shell of the cylinder _A_, said cylinder must turn or revolve a little in the direction of the arrow _j_, and also that the next succeeding tooth of the escape wheel will engage the cylinder on the outside of the half shell, falling on the dead or neutral portion of said cylinder, to rest until the hairspring causes the cylinder to turn in the opposite direction and per on the outside of the cylinder to assu

The first problem in our consideration of the theoretical action of the cylinder escapee the parts we have described so as to have these two ular values To explain e , that as our escape wheel has fifteen teeth and we ive two ie to have these half-tooth ular values; and also each impulse must convey the same power or force to the balance All escape wheels of fifteen teeth acting by half irees (minus the drop) of escape-wheel action; or, in other words, when a tooth passes out of the cylinder fro 126, the form of the impulse face of the tooth and the shape of the exit lip of the cylinder ular motion of the escape wheel The entire power of such an escape wheel is devoted to giving iularsuch ile” This ”lifting angle” is by horological writers again divided into real and apparent lifts This last division is only an iinary one, as the real lift is the one to be studied and expresses the arc through which the i the act of escaping, and so, as we shall subsequently show, should no more be counted than in the detached lever escapement, where a precisely similar condition exists, but is never considered or discussed

We shall for the present take no note of this lifting angle, but confine ourselves to the proble our escape-wheel teeth and cylinder that each half of the tooth space shall give equal impulses to the balance with theof an escape-wheel tooth and cylinder on an enlarged scale; our inal system, which is very simple yet complete

DRAWING THE CYLINDER ESCAPEMENT

All horological--and for that s are based on two systeular movement

For the first measurement we adopt the inch and its decirees,the latter the usual plan is to employ a protractor, which serves the double purpose of enabling us to lay off and delineate any angle and also to raphic raphic method we propose to solve very siical delineations As an instance, we propose to draw our cylinder escapee, showing one-hundredths of an inch, and a pair of dividers; the degree rees of radii, as will be explained further on