Patent GB-755503-A (GB)
Title: Improvements in and relating to photoflash bulb holders
IPC: G03B15/04
Filed: 1952-11-11
Abstract: 755,503. Photographic flashlight apparatus. KALART CO., Inc. Nov. 11, 1952 [Dec. 1. 1951], No. 28387/52. Class 9(2) Photographic flashlight apparatus is provided comprising a holder for a plurality of flash bulbs, each bulb consisting of a globule 1 enclosing the combustible foil or wire and a primer connected to two external contact elements 2, 3. The bulbs are joined together by a rupturable neck portion 4 and are housed in a tube 5 .of. metal or transparent plastic material closed at the base by a cap 6. At the top of the tube 5 is a reflector 7 and a bulb holder 8 having diametrically opposed slots 9 for ejection of the bulb and notches 10 to receive the terminals 2, 3. The slots 9 extend to longitudinal slots 11 in which the terminals 2, 3 slide as the bulbs move upwardly. in the tube. The holder 8 may be in two sections separated by an insulating strip 14, the two sections being connected in circuit with the terminals of a, source of electric current, which may be batteries housed in a casing 15 on the tube. The lowermost bulb in the tube is supported on a spring 20<SP>1</SP> resting on a backet 20 extending into a housing 21 fixed to the tube. The bracket 20 is moved along the tube by means of two levers 22, 23 having a common -pivot 24, a spring 25 being arranged between the bent-up inner ends of the levers. In the housing 21 is a longitudinal slot 26 through which the levers extend to form an actuating handle by which the bracket and bulbs can be raised. The spring 25 holds the lever 22 in frictional engagement with the wall of the housing 21 to secure the bracket in any required position. Used bulbs are ejected by a spring-biased plunger 30 which extends through the reflector 7 and carries a curved disc 32 engaging the bulb 1. On removing the cap 6 and bracket 20, a string of bulbs is inserted into the tube and the leading bulb 1 turns spring- pressed levers 13 pivoted on the sleeve 8 until the wide part of the-bulb has passed the levers, whereupon the levers return to their initial position. Engagement of the terminals 2, 3 in the notches 10 limits the upward movement of the bulbs. After firing the leading bulb, the plunger 30 is depressed and causes the neck 4 to rupture, whereupon the used bulb is ejected and the next bulb can be moved into the firing position. In a modification, the bracket 20 is replaced by a lifting mechanism comprising two parts 35, 36, Fig. 3, with a common pivot 37. A spring 38 presses the lower ends of the parts 35, 36 against the tube. By pressing the parts 35, 36 inwards, the lifting mechanism can be moved to raise a rod 40 carrying a platform 39 which supports the lowermost bulb. The contact elements consist of two clamps 42 mounted on a bracket 43, preferably transparent, secured to the tube 5. Each clamp is connected with a switch (not shown) and electric terminals 45, 46 mounted on an insulating sleeve 47 surrounding the tube 5. Mounted on the bracket 43 and extending: over the uppermost bulb is an ejector arm 48. On firing the uppermost bulb, the string of bulbs is moved upwards forcing the used bulb against the arm 48. which deflectsthe bulb causing fracture of the neck 4, whereupon the contacts of the following. bulb can engage the clamps 42. Apparatus for use with flash bulbs which are not. joined together comprises a housing 51 supporting the reflector 7, Fig. 7, a synchronizer 52 and a shoe 53 for attachment to a camera. 'The bulbs are placed in U- shaped carriers 61 attached to an endlessbelt 54 guided by rollers 55, 56, the roller 55 being mounted on a shaft projecting. from the housing and ending in a wingnut by which the roller can be rotated to advance the bulbs. The rollers may have recesses engaging projections on the innerwall of the casing to position the bulbs. When in the firing position, the contacts 2, 3 of the bulb engage springy prongs 70, which together with guides 71, 72 hold the - bulb in position. A battery may be housed' within the belt 54. Openings aligned with the guides 71, 72 are provided in the front and rear of 'the drum, so that the leading bulb can be pushed into the firing position,. from which it is ejected by the next succeeding bulb. In an alternative arrangement, the bulbs are placed in springy clamps on a cylindrical drum rotatable within a casing, the bulbs being moved as before into the firing position where they are gripped between guides 71, 72. The firing'current may be supplied by a battery housed in the drum. Guiding grooves may be formed in the clamps to .receive the terminals 2, 3 and so align the bulb with, the prongs 70. The axis of the reflector instead of being at right angles to the bulb casing may be tilted relatively to the housing. In another modification, Fig. 14, the magazine for the bulbs is. combined with the reflector. A casing 100 attached to the reflector contains a rotatable drum 101 carrying spaced clamps 103 between which the bulbs are placed. The casing is mounted on a tube 105 having a shoe 106 for at-. tachment to.a camera and a synchronizer 107. In the firing position, the bulb is held between springy contact clamps 111, pivotally supported on a shaft 113, and extended to form bell-crank levers with short arms 114 pivoted to an arm which is pivoted on a pin 116 extending through a wing nut 102. A bifurcated spring 118 engages the arm 115. To move a bulb into the firing position, the drum 101 is rotated' by means of the nut 102 until a bulb registers with an opening 121 in the reflector. Then, by pushing the pin 116 inwardly, the clamps 111 swing inwardly, against the action of spring 118, to engage: a bulb, anyused bulb in the clamps being forced out by the incoming bulb. When the pin 116 is released, the spring 118 forces the clamps back to the firing position.