Patent GB-536486-A (GB)
Title: Counting and indicating device
IPC: G01F15/07
Filed: 1939-08-08
Abstract: 536,486. Counting-apparatus. TRIGGS, W. W. (Brodie Co., R. N.). Aug. 8, 1939, No. 22915. [Class 106 (i)] In a transfer mechanism of the snail cam and co-operating lever type, the lever is U- shaped the free end of one arm being spring- pressed against the cam, while the free end of the other arm engages the ratchet on the next shaft and is provided with a cam to prevent overthrow. The counter A and indicating mechanism B are located in a casing 16 on top of the casing 10 of a fluid meter. The meter spindle drives a gear 24 and this and the casing 16 are provided with slots so that the casing and counter driving shaft 27 may be withdrawn bodily and adjusted through an angle and replaced, the casing being located by a lug engaging one of the slots and the shaft 27 coupled by a cotter engaging a slot on the boss of the pinion 24 the casing being secured by a chordal bolt engaging a circumferential groove on the casing. Indicating mechanism. The shaft 27 drives through bevels 96, 97 a shaft 98 and this through a gear 99 a counter 100 of ordinary construction. The shaft 98 drives through a friction clutch 102 and bevels 101, 103 a fraction disc 105. The shaft of this drives through gear 114, 115 the shaft 116 of transfer mechanism which drives the first or units member of a series of overlapping indicating discs a single numeral on each of which is visible through one of a series of windows 112, 111 in the casing 16. Transfer mechanism. The wheel 115 is fast with a cam 117 but drives through pin 120 anp slot 119 a snail cam 118 past a shaft 116. When the fraction wheel and consequently wheel 115 has made a complete revolution, the roller 121 carried by the arm 124 of a U-shaped spring transfer lever 124, 125, 126 pivoted at 123 is at the high point of the cam and presses the latter relatively to the wheel 115 snapping to the low point. The arm 126 rises and moves the ratchet wheel 130 through one tooth, a cam surface 132 on the arm 126 preventing overthrow. The wheel 130 is loose on the shaft 129 but is joined with ratchet teeth 134 engaging spring pivoted pawls on the cam 137 and through these pawls, the shaft 129 and dial are moved through 1/10th of a revolution. Similar transfer levers and cams are used for the "tens," "hundreds" &c. dials, the slotted cam and pin being omitted for the highest denominations. Zeroizing mechanism. The reset shaft 138 is rocked by reciprocating the handle 139 on which is a bell-crank lever 140 one arm of which through a pin 141 rocks a lever 143 pivoted at 144 to release the clutch 102 after which the pin 145 moves a guided slide rod 94 against its spring 148 so that pins 152 engage the teeth of ratchets 151 at the rear of shafts 129 &c. and move the dials to zero where the pins engage the wide gap of the ratchet wheel. A transfer release bar 153 is reciprocated by a pin 150 on the slide 94 and is provided with lugs 154 which engage lateral ears 155 on any of the transfer pawls 126 which have been lowered to pick up position and will rock them so that no transfer takes place. A lever with a cam slot 166 is also rocked so that a lug engages a pin 168 on the shaft 116 so that the fractions wheel is properly zeroized.