Patent GB-190715681-A (GB)
Title: Improvements in Recording Speed Indicators.
Inventor: ISZARD CHARLES FRANKLIN
Filed: 1907-07-08
Granted: 1908-05-07
Abstract: 15,681. Iszard, C. F. July 8. Speed indicators; registering observations by instruments.-In a recording speed indicator, a drum bearing a record-strip is rotated by an epicyclic clockwork train and is simultaneously moved parallel to the axis of rotation,. while a flexibly-mounted marking-device is operated at the completion of every mile travelled by the vehicle by.means of a cam driven through worm gearing from a suitable rotating part. A hollow shaft c, Fig. 8, of rectangular section, carrving a fixed toothed wheel c<2>, slides in the sleeve b<1> of similar section, which is in turn supported in the plate b and is normally frictionally prevented from rotating therein by means of its flange b<2> and screwed collar b<4>. A shaft t c<1> is supported at one end in the plate d<1>, which is in turn fastened to the frame d<4> and thus to the drum e, and at the other in the shaft c. The shaft c' carries a fixed toothed wheel c<6>, which is driven by the clock-work mechanism shown and actuates the combined toothed wheels c<4>, c<3>. The shaft c being normally prevented from rotating in the sleeve b<1> as described, the wheel c<3>, together with the clock-work mechanism and the drum attached thereto, rotates about the axis of the wheel c<2>; but the drum may be turned manually, in order to position it with respect to the marking-device, without affecting the drive, in which case the sleeve b<1> rotates with it. A simultaneous longitudinal movement is given to the drum by means of a screwed spindle d<5> which is fixed thereto. A weight e<1> is arranged in the drum in order to counterbalance the mechanism within it. The mainspring d<14> of the clock work can be wound up from the spindle d<18>. The operation of the recording-device is as follows. A flexible shaft k<1>, Fig. 1, operated by the vehicle, drives through the sleeve l and ratchet-wheel l<4> the worm-shaft k and wormwheel i, the shaft i<3> of which carries a cam i<4> adapted to depress the inking-device h, Fig. 5, mounted upon the flexible strip o, Fig. 1. The needle-valve h<5> coming into contact with the recordstrip f, Fig 7, mounted upon the drum e, is raised, and thus permits a flow of ink and causes a mark to be made on the strip. To record the commencement of a journey, the shaft k, which is pivotally mounted at one end and held in a sliding spring-controlled bearing at the other, is depressed, thus disengaging the worm from the worm-wheel. The wheel i is next rotated by hand, causing the inking-device to be operated ; it is then turned, before the shaft k is replaced, until the line i<1> is directly below the fixed pointer i<2>, ia which position a complete rotation, equivalent to a mile of travel, is necessary before the inking-device is again operated by the cam i<4>. This initial mark cannot be made by an unauthorized person as the apparatus is urder lock and key. A spiral line on the recordstrip f, which suffices for a twenty-four hours' record, is divided into numbered lengths representing the hours, quarters, and five-minute spaces. The spindle d<5> and attached drum can be withdrawn and replaced in their initial position by first raising the arm d<10>, which is held in agreement with the frame d‹ by a catch d<11> and pin d<12>. The record-strip is at all times: visible, and' indicates the distance travelled by the vehicle in a forward direction in a given time, the speed, and the time during which the journey was made.