Abstract: A security barrier apparatus suitable for use in residential, farm and industrial settings includes a motor, a chain and a brake mechanism for engaging the chain. The apparatus is mounted to a first support such as a post. The chain extends from the first support to a second spaced support and is raised and lowered relative to the ground by operation of the motor. The motor may be remotely actuated by an electronic transmitter. The apparatus further includes protective features to prevent damage to the motor in the event that a vehicle collides with the chain.

Abstract: A security barrier apparatus suitable for use in residential, farm and industrial settings. The apparatus includes a motor, a cable, a chain secured to the cable and a brake mechanism for engaging the chain. The apparatus is adapted to be mounted to a first support such as a post. The chain extends from the first support to a second spaced support and is raised and lowered relative to the ground by operation of the motor. The motor may be remotely actuated by an electronic transmitter. The apparatus further includes protective features to prevent damage to the motor in the event that a vehicle collides with the chain.

Abstract: A multiple blow percussion drill assembly is specially configured to provide significantly increased maintainability and adjustability in the field, thereby greatly extending its service life and usefulness over a wide variety of drilling conditions. Both spring replacement and impact hammer delay time variations are rapidly accomplished by virtue of unique positioning and interactions of the internal components, without the need for dissassembly of the sealed high impact energy portion of the drill assembly. Advantageously, a first chamber housing the high impact energy transferring components is isolated from a second chamber housing the control components, such that the control components may be rapidly cleaned, adjusted, or replaced via a simple access port.

Abstract: Shoe members and drill shank members for large diameter cable drilling bits are provided with a tongue on one of the members that projects axially relative to the drill shank member and with an arcuate lip and projecting stop on the other of the members to trap the tongue and prevent radial movement of the shoe member in response to radially directed forces caused by the spinning of the bit in drilling operations. Such forces would impose shear stresses on the fastening members that extend through the shoe member and axially into the drill shank. Four embodiments are disclosed: a spudding bit, two star bits and a scow bit.

Abstract: A multiple drill stem for cable tool drilling operations, in which the drill stem is repeatedly hoisted and dropped to impact, has an internal hammer that moves a short distance to strike an anvil in a lower end of a drill stem casing. The improvement relates to a cocking spring that is positioned along an uppermost portion of the hammer and away from harmful debris that collects where the hammer strikes the casing anvil. The casing bears against an upper hammer anvil to cock the spring between a spring-compressing flange at one end and a restriction in the casing interior that blocks an opposite end of the spring, but allows the hammer to slide through it. The spring is further compressed when the drill stem is dropped to a point of initial impact, so that the hammer strikes a follow-up blow on the lower casing anvil. A method of assembling the drill stem is also disclosed.