GB197014A - Improvements in or relating to means for preserving an electric motor against the action of an injurious surrounding medium whilst ensuring lubrication and cooling of the motor - Google Patents

Abstract

197,014. Longue, R. Feb. 3, 1922. Addition to 159,862. Motors, cooling; insulation; casings.- In a motor fitted with oil or other liquid to protect it from the action of an injurious surrounding medium and having means for equalizing the pressures of the internal and external media as described in the parent Specification, the bearings are enclosed in oil-filled casings communicating with a chamber having a movable or distortable wall for equalizing the pressures of the lubricating oil and surrounding medium independently of the liquid in the main motor casing. The liquid in the main casing may be separately cooled. In the form shown in Fig. 1, the bearings a are contained in casings c filled with lubricating oil and communicating with a vessel having a piston h whereby the oil pressure is equalized with that of the surrounding medium. The oil which fills the motor casing d, and which is unsuitable for lubrication, is equalized in pressure by another piston i. For exact equalization of the pressures in the casings c, d and the surrounding medium, the axes of the pistons are arranged in the same horizontal plane as that of the motor shaft. Fig. 3 shows a form in which equalization occurs at the contact surface between the lubricating and insulating oils and the water surrounding the motor. The bearing members j communicate by pipes l, m with a chamber k, and the motor casing d communicates at s with another chamber q. The chambers k, q are connected at o, t with tanks n, r into which the surrounding water also enters through pipes p, u. The contact surfaces between the oil and water in the tanks n, r is in the same horizontal plane as the axis of the motor shaft. When the motor works in a deleterious atmosphere, this atmospheres has access to water which rests on the oil in the tanks n, r, or the tank r may be omitted. The oil may be cooled by a water circulation in the space between the motor casing v, Fig. 5, and a corrugated cylindrical liner x, ducts z, w and baffles 2, 3 being provided to direct the oil as shown by the arrows. Alternatively, the oil may flow in contact with a waterpipe coil in the motor casing or through a cooling device which is independent of the motor.