JPH0540968Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a twin-screw mixer for producing ready-mixed concrete by mixing gravel, sand, cement, water, and additives.

Conventional twin-shaft mixers have two parallel kneading shafts that rotate in opposite directions and rigid steel arms pivotally attached to them. The kneading blades at the tips of the arms rotate to move the materials, thereby kneading them.

Problems that the invention aims to solve In order to produce high-quality ready-mixed concrete, it is desirable that a cement shell be formed around the sand and gravel used as mixing materials, but conventional twin-shaft mixers cannot In this method, various materials are moved at the same speed as the mixing blade rotates, and because there is no relative speed between the various materials, it is difficult for cement to penetrate between gravel and sand, and cement is formed into small lumps. There is a problem with whether the lump is difficult to crush.

Means for Solving the Problems The present invention was developed in view of the above points, and consists of an arm in which an appropriate number of flat springs are stacked radially around two parallel kneading shafts rotating in opposite directions. The overlapping flat springs are formed so that the tip on the opposite side to the rotational direction of the arm gradually becomes shorter, and a kneading blade is arranged at an appropriate angle at the tip of the arm, Using the restoring action of the arm that is bent by the kneading load, it applies an impact to the kneaded material.
By providing relative speed between the materials, mixing is promoted and high quality ready-mixed concrete is produced.

Function: When materials are kneaded using the twin-screw mixer of the present invention, the arms that support the kneading blades are formed by overlapping an appropriate number of flat springs. If the above kneading load is applied, the arm supporting the kneading blade will be largely bent from the pivot point of the kneading shaft. When the kneading load is reduced, the kneading blades strike the materials due to the large deflection and strong restoring action of the flat springs, and this impact gives different accelerations to each material. Therefore, cement can easily penetrate between gravel and sand, and cement lumps are also ground, making it possible to produce high-quality concrete.

Embodiment 1 is a kneading tank of a two-screw mixer, in which a pair of kneading shafts 2 and 2' are rotatably supported in opposite directions to the kneading tank 1, and each of the kneading shafts 2 and 2' has a An appropriate number of arms 3 are arranged radially in the radial direction. The arm 3 uses a flat spring having an appropriate bending stress, that is, a stacked flat spring made of overlapping flat springs, and a kneading blade 4 having an appropriate angle with respect to the kneading shafts 2, 2' is attached to the tip with a bolt. It is fixed by a fastener 5 such as a nut. Reference numeral 6 denotes a gate that closes a discharge port drilled across the entire axial region of the lower part of the kneading tank 1.

Effects of the Device As described above, the device of the present invention is effective against deflection caused by a large rotational moment around the pivot point of the kneading shaft of the arm 3 formed by overlapping an appropriate number of flat springs, and its strong restoring action. The material is struck by the kneading blade 4 due to the strong repulsive force generated, and this impact gives different accelerations to each material, making it easier for cement to penetrate between sand and gravel, and also crushing cement lumps. Because it is dispersed, it is possible to produce concrete of higher quality than before.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional front view of the two-shaft mixer, FIG. 2 is a longitudinal sectional side view of the same, and FIG. 3 is an enlarged view of the arm. 1...Kneading tank, 2, 2'...Kneading shaft, 3...Arm, 4...Kneading blade.

Claims (1)

[Scope of utility model registration request] An arm in which an appropriate number of flat springs are superimposed radially in the radial direction is pivotally attached to two parallel kneading shafts rotating in opposite directions, and the superimposed flat springs 1. A two-shaft mixer characterized in that the tip of the arm is formed so as to become gradually shorter, and kneading blades are arranged at an appropriate angle at the tip of the arm.