Abstract: This invention relates to a hose coupling having mounted thereon a leaf spring locking member of such a configuration that the free end is so disposed that it constitutes a stop which is shiftable by the guard arm of the other one of a pair of hose couplings out of the pathway of this guard arm on the other one of the hose couplings as the one hose coupling and the arm thereon are rotated toward the fully coupled position of the pair of hose couplings. The configuration of the stop is such that the resiliency of the leaf spring locking member, upon the pair of couplings reaching their fully coupled position in which the arm passes out of contact with the stop, shifts this stop to a position in the pathway of the arm thereby preventing unwanted uncoupling of the pair of fully coupled hose couplings until the leaf spring is manually deflected to shift the stop out of the pathway of the guard arm.

Abstract: An acoustical sparker probe apparatus is described for generating a high energy acoustical pulse at a frequency between 600 hz and 10 khz in a borehole having a diameter between 50 mm and 100 mm. The apparatus includes an uphole electronic system having a low voltage AC power source which is directed through an electrical cable to a borehole probe that is moved along the length of the borehole. The borehole probe has a sparker section with electrodes for generating a high energy acoustical pulse when a high energy electrical spark discharge is created between the electrodes. The probe has a high voltage DC energy section with a voltage multiplying and electrical energy storage for receiving the low voltage AC from uphole and creating and storing over 100 joules of electrical energy at a voltage above 1000 volts within the probe. The probe has a triggering network for rapidly discharging the high voltage electrical energy across the electrodes at above 5000 amp for 10 .mu.

Abstract: A brake control valve device, for railway vehicles, embodies means to enable this control valve device to be selectively conditioned for effecting either a direct release of the brakes or a graduated release of the brakes accordingly as a removable selector valve cover member having a ported face is secured to a ported face formed on the exterior surface of the control valve device in either a first or a second position with respect to this ported face on the control valve device.

Abstract: A brake control valve device operated by a reduction in brake pipe pressure on one side of a movable abutment relative to control reservoir pressure on the opposite side embodies in the abutment a control reservoir charging valve mechanism, a filter and a choke arranged in series. The valve mechanism comprises a spring-biased valve slidably mounted in a ported bushing carried by the abutment. Two spaced-apart stops carried on the abutment enable relative movement between the abutment and the valve whereby, in one position of the valve, fluid under pressure may flow from the brake pipe to the control reservoir to effect charging thereof via the ported bushing, a passageway in the valve and the choke, and, in a second position of this valve, this charging communication is closed.