Abstract: In a drill resistance measuring apparatus including a drive unit and an attachment for determining the internal state of trees or wooden structures by determining the torque required to drive a drill into the wood, means for plotting and storing the torque depending on the penetration depth of the drill are included in the drive unit attachment, which includes a coupling portion for coupling to the drive unit and a transmission mechanism exchangeably supported in the attachment to permit an exchange of the transmission mechanism for a change of the transmission ratio for operating the drill at various speeds.

Abstract: An endoprosthesis for a femoral hip joint comprises a stem (1) with a collar (3) which bears against a resected bone surface and has a blocking cone (4) on which the ball head (5) is positioned. A screw (12) which grips the prosthesis as a tensioning stay passes through a lateral bore extending obliquely downward and outward through the femur. The prosthesis stem is designed to permit cementless fixation and to prevent crack formation in the femur due to rigidity of the stem, even under extreme loads. To this end, the prosthesis stem (1) is lodged in a mating fit in a medullary nail (7) driven into the medullary canal, and the distal region of the prosthesis stem (1) is elastic.

Abstract: In a spring-loaded missile projecting device such as a bow including a center holding part with outwardly projecting support portions having bow members pivotally mounted thereto with a string extending between the free outer ends of the bow members, elbow linkages are arranged between the support portions and the bow members such that the elbows are slightly bent away from the string when the string is straight and the elbow linkages are spring-loaded so as to be forced toward the string for tensioning the string, so as to provide for a relatively large initial string tensioning force which does not appreciably increase by pulling out of the string thereby generating a relatively constant arrow-accelerating force and requiring a relatively low holding force.

Abstract: Device for holding together the fractured ends of a bone in a living body, including an elongate holding member arranged to be secured to the bone and provided, for this purpose, with openings for holding connecting elements, with a certain elasticity being retained, and reinforcement members forming a unit with the holding member, extending in the length direction of the holding member and disposed along opposite sides of each opening.

Abstract: A bow includes a centrally arranged handle and a bow limb emanating from each end of the handle, with a cord being tensioned between the outer ends of the bow limbs. The inner ends of the bow limbs are shaped into forks whose tines (which act as springs) are fastened separately, each to a frontal face of the handle. The special configuration increases the energy stored in the bow and reduces the force required for tensioning the cord.