Abstract: Provided is a thermostat with reduced temperature difference within the tank when a solution is being heat-treated. Stirring guides (114) for guiding a water-flow generated by a stirring bar (113) to both ends of a tank (106) in the longitudinal direction are disposed on the bottom of the tank (106). Thus, the water-flow generated by the stirring bar (113) is efficiently guided to both ends of the tank (106) in the longitudinal direction while keeping its momentum, and therefore a circulating water-flow for homogenizing the temperature of the water within the tank (106) can be effectively generated.

Abstract: Provided is a thermostat with reduced temperature difference within the tank when a solution is being heat-treated. Stirring guides (114) for guiding a water-flow generated by a stirring bar (113) to both ends of a tank (106) in the longitudinal direction are disposed on the bottom of the tank (106). Thus, the water-flow generated by the stirring bar (113) is efficiently guided to both ends of the tank (106) in the longitudinal direction while keeping its momentum, and therefore a circulating water-flow for homogenizing the temperature of the water within the tank (106) can be effectively generated.

Abstract: A platform shaker for stirring liquid chemical compositions provides a swirling motion in three dimensions. The magnitude of the three dimensional motion can be continuously adjusted while the shaker is in operation. Additionally, the platform of the shaker returns to the horizontal orientation after stirring is halted so as to maintain liquid samples well within the container placed on the platform. The novel platform shaker is useful for various analytical procedures such as DNA extractions, hybridizations, and gel staining in genetics, biology, and molecular biology. It is particularly appropriate for DNA extractions because the tilt angle of the platform as well as the swirl rate can adjust according to characteristics of the DNA, for example, to provide for a small tilt angle and a fast swirl rate for a short chain DNA, and for a large angle and a slow swirl rate for a long chain DNA.

Abstract: A temperature regulating container with a heater and a metal block in which test tubes with test samples are therein inserted and kept isothermally provides a plurality of heat pipes embedded in the metal block and extended to the heater section located at bottom of the metal block uniformally maintain the temperature in the metal block. Heat tubes are further extended downwardly to a cooling chamber provided at the bottom of heater such that when a cooling medium, water or air flows in the cooling chamber, the metal block is cooled respondingly provide accurate cooling of test samples in test tubes according to a desired program.

Abstract: In a rotary head assembly in which a rotary member (14) provided with a magnetic head (23) in the gap between the upper and the lower fixed cylinders (17 and 18) having nearly equal diameters and arranged coaxially with each other is turned, use is made of a structure such that the upper and the lower fixed cylinders (17 and 18) are secured in place and supported by a fixed shaft arranged coaxially therewith, whereby more stable magnetic tape running has been realized, while achieving ease of assembling with high accuracy and reduction of power consumption.

Abstract: Mechanical vibration of a rotating test body is translated into a periodic signal which represents a combined vector of the unbalance means of the rotating body and the mechanism that rotates it. The periodic signal is divided into two orthogonal vector components. The magnitude of the two vector components are converted into digital signals and applied to a computer. Unknown values of four constants are determined by a preliminary test having three successive stages. In the first and second stages the test body is rotated to register the digital signals; in the second state the angular position of the test body is displaced a predetermined amount with respect to its first stage position. In the third stage of the test, a trial dead weight of a known mass is mounted on the test body and rotated to register the digital signals. The computer operates on the registered digital signals to determine the four constants in accordance with a set of equations.