JPS5853737A - Rotary bending load test device - Google Patents

Abstract

PURPOSE:To enable to perform a testing of a material for rotary bending under a particular atmosphere, by a method wherein one end of a test piece is fastened, a magnet is secured to the other, and a load is remotely applied by a rotary magnetic pole through a side wall of a receptacle. CONSTITUTION:The upper end of a test piece 1 is held between the nip formed by a device 3 hanging down from the ceiling 2A of a pressure receptacle 2, and a disc-shaped magnet 4 is secured to the lower end thereof. At the outside of the pressure receptacle 2, a rotary shaft 5 is supported by bearings 6 and 7, a U-shaped rotor 8 is mounted, and an electromagnet 9 is located. The electromagnet 9 is positioned facing and opposite to the permanent magnet 4 through the medium of a pressure receptacle side wall made of a nonmagnetic substance, and is excited so as to repel each other. A fatigue test can take place by applying a bend moment test piece 1 through rotation of the rotary shaft 5, and a bending load can be applied to the test piece 1 by exciting the electromagnet 9 through bringing of the rotor into a stationary state. A strain produced at the fixed end of the test piece 1 is measured by a strain gauge 12.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotary bending loading device for materials, and more specifically, a device for rotary bending and fatigue testing of materials in a special atmosphere isolated from the outside world such as high pressure, high temperature, and low temperature. regarding such equipment.

Conventionally, as seen in Japanese Utility Model Publication No. 56-19722, it has been known to perform a rotational bending test on materials at atmospheric pressure.
Alternatively, no method has yet been proposed that performs the process under a special atmosphere such as at a high temperature of 500° C. or higher.

An object of the present invention is to provide a loading device that performs a rotating bending fatigue test by remotely applying force to a material without directly contacting the material in a state completely isolated from the outside world.

The rotating bending loading device of the present invention fixes one end of the test piece,
a test piece support device having the other end of the test piece as a free end; a magnet disposed coaxially with the central axis of the test piece at the free end and magnetized in the axial direction of the test piece; and the test piece and its support. a container that isolates the device and the permanent magnet from the outside world and in which at least a peripheral portion of the magnet is made of a non-magnetic material; and a sealed chamber that is located outside the container and is magnetized in a direction that repels the magnet; It has a rotating magnetic pole that is rotationally driven along the outer periphery of the test piece, and a strain detector that detects the strain that occurs at the fixed end of the test piece, and applies a rotating bending load to the test piece by the repulsive force of the permanent magnet and the rotating magnetic pole. It is characterized by being configured to give.

Hereinafter, embodiments of the present invention will be described based on the drawings.
A disk-shaped permanent magnet 4 is fixed to the test piece 1, and this permanent magnet 4 has a magnetic pole N8 in the axial direction of the test piece at its periphery coaxial with the central axis of the test piece 1. These test pieces 1, their supporting devices, and the permanent magnets 4 fixed to the free ends of the test pieces are as follows:
It is completely isolated from the outside world by the pressure vessel 2. In addition,
The pressure vessel 2 is made of a non-magnetic material such as austenitic stainless steel, and has a cylindrical shape. A rotating shaft 5 is mounted on a bearing 6 outside the container on the central axis of the cylindrical expansion pressure container 2.
A U-shaped rotor 8 is provided on this rotating shaft 5, and this U-shaped electromagnet 9 faces the permanent magnet 4 through the side wall of the non-magnetic pressure vessel, and its magnetic pole direction is the same as that of the permanent magnet. They are excited in the same direction and repel each other.

Incidentally, the other end of the U-shaped plate 8 serves as a balance weight for the electromagnet 9. A slip ring 1o is provided on the rotating shaft 5, and the coil 9A of the rotating electromagnet 9 is energized from the excitation device 11 via the slip ring 1o. A strain gauge 12 is built in between the two ceilings of the pressure vessel 2 and the test piece clamping device 3 to detect the movement occurring at the fixed end of the test piece, thereby making it possible to measure the bending moment. This bending moment signal e1 and the freely settable reference voltage 82 are input to the error amplifier 13, and the output thereof is introduced to the excitation device 11 to form a feedback loop.

When using this device to perform a rotating bending fatigue test under high pressure, for example, the inside of the pressure vessel 2 is pressurized to a predetermined pressure, and the reference voltage e is set to a value corresponding to the magnitude of the predetermined bending moment. setting, and rotate the rotating shaft 5 at a predetermined repetition period. Every time the rotor 8 rotates once, the permanent magnet 4 constantly receives a repulsive force in the radial direction, which causes the test piece 1
is subjected to a bending moment, so a fatigue test can be performed by continuously rotating the tab 8.

Further, by keeping the rotor 8 stationary and exciting the electromagnet 9, a bending load can be applied to the material 1.

As a variant embodiment of the invention, the electromagnet 9 can be replaced with a permanent magnet. Furthermore, it is also possible to use a heat insulating container instead of a pressurized container and conduct the test in a high or low temperature atmosphere.

According to the present invention, a permanent magnet is fixed to the free end of the test piece, and magnetic poles such as electromagnets are provided through the side wall of the container, and a load is applied remotely to the test piece, so high pressure, high temperature, low temperature, etc. It has become possible to perform rotational bending tests on materials under special atmospheres. Also, since it uses the repulsive force of the magnetic poles,
It is also easier to control the force compared to methods that use suction force. Incidentally, when using an attractive magnetic field, the force is very difficult to control because the direction of action of the force is the same regardless of the change in the distance between the magnetic poles.

[Brief explanation of drawings]

The drawings are configuration diagrams showing embodiments of the present invention. 1...Test piece, 2...Container, 4...Permanent magnet, 8...Rotor, 9... Electromagnet, 12...Strain gauge. Patent applicant: Shimadzu Corporation Agent: Patent Attorney Nishi 1) Arata

Claims (1)

[Claims] A test piece supporting device having one end of the test piece fixed and the other end of the test piece being a free end; magnet and
A container that isolates the test piece, its support device, and the permanent magnet from the outside world, and in which at least a peripheral portion of the magnet is made of a non-magnetic material, and a container located outside the container in a direction that repels the magnet. It has a rotating magnetic pole that is magnetized and driven synchronously along the outer periphery of the sealed chamber, and a strain detector that detects the strain that occurs at the fixed end of the test piece, and the repulsion between the permanent magnet and the rotating magnetic pole A rotary bending loading device configured to apply a rotary bending load to a test specimen by force.