GB857022A - Control devices for pest scarers - Google Patents

Abstract

857,022. Pest scarers. BLANCH & CO. Ltd., A. B. Jan. 16, 1957 [May 10, 1956 ; July 13, 1956 ; Aug. 7, 1956], Nos. 13588/59, 13589/59 and 13590/59. Divided out of 857,021. Class 6(2). [Also in Group XXXVIII] Fig. 1 shows a pest scarer in which a generator 5 containing calcium carbide and water produces acetylene gas which passes through tube 6 via a T-piece 7 to a control mechanism 9 and a control device 11. The control mechanism 9 is connected to an ignition chamber 13 and expansion chamber 14 which are supported by a stand 15 on the ground. The control device 11 is provided with spikes 17 which enter the ground so that it is supported independently of the main part of the pest scarer. The pest scarer may be as described in Specification 734,175. The control mechanism 9 comprises a piston or diaphragm upon which the acetylene gas acts so that the diaphragm is displaced to open a valve and allow the gases to pass to chamber 13. The diaphragm also controls an ignition such as a flint sparking device so that when the gas passes to the ignition chamber 13 the diaphragm is spring returned and thus actuates the sparking mechamism to ingite the gases. As shown in Fig. 3 the control device 11 comprises a clockwork mechanism 18 carried by a plate 19 welded to the lid 20 of a casing, the lid closing a pot 21 having a sealing ring 22 of rubber. The lid 20 is sealed tightly by means of the stud and wing nut 23, 24. The clockwork mechanism 18 drives via gearing a pair of plate like cam members 32 and a clock dial member 33 the members 32 may be angularly adjusted. A cam follower 34 controls a gas valve 37 so that during a period determined by the setting of the clock dial gas escapes through port 39 to the atmosphere, instead of to the ignition chamber. In a modification, Fig. 4 (not shown), the cam members control a flap valve via a lever which when open permits the gas to escape to the atmosphere. The gas valve may also act as a pressure release valve to permit discharge of the gases when a predetermined pressure is reached. The valve may be of the ball cup or piston type Figs. 1-6 the third Provisional Specification (not shown).