CN105606031A - Micro displacement testing system - Google Patents

Abstract

The micro-displacement testing system belongs to the field of micro-mechanics. It includes a temperature control system and an imaging system; the temperature control system includes a spring dynamometer, a thermocouple, a PC, a DC power supply and a switch; the spring is a shape memory alloy wire, and the spring dynamometer is connected in series with a light bulb, a DC power supply and a switch to Temperature control, and provide light source for the imaging system; the imaging system consists of five parts: the optical bench, the structure to be tested, the bulb, the convex lens, and the light screen; the optical bench is divided into two parts: one is the lower half slide rail structure; the other is the upper half The half part is equipped with a baffle, and the structure to be tested that can transmit light is pasted on the baffle; the bulb is fixed on one side of the baffle, and the convex lens and light screen are located on the other side of the baffle in turn, and ensure that the light bulb, the structure to be tested, and the convex lens And the light screen four are located on a horizontal line. The measured structure is projected onto the light screen through a convex lens to form an inverted enlarged real image, and the movement of each point on the measured structure during the stretching process is observed on the light screen to realize the displacement measurement and recording of the target point.

Description

Micro displacement test system

technical field

The invention relates to a micro-displacement testing system combined with shape memory alloy characteristics for component deformation and micro-displacement testing, and belongs to the technical fields of photomechanics, engineering materials, component deformation, micro-electromechanical systems and micro-displacement testing.

Background technique

At present, the micro-displacement test systems used in the prior art are mainly divided into two categories: bulk structures temporarily built on the test bench and portable commercial micro-displacement test systems. The test system built on the test bench is not suitable for on-site component deformation measurement. Commercial micro-testing instruments such as MicroSense's high-precision capacitive displacement sensors, grating scales for high-precision motion platforms such as ultra-precision diamond machine tools, and Renishaw dual-frequency laser interferometer XL-80 and other micro-displacement measuring instruments with different measurement principles. Although high-precision displacement measurement can be realized on site, the cost is high and it is not universally applicable. At the same time, most of the existing displacement test systems output the photoelectric signal, and then process and convert the signal in the PC to read the displacement data.

The purpose of the present invention is to provide a high-precision micro-displacement testing system, which is easy to carry, low in cost, and easy to operate. The displacement data can be read directly at the terminal, easy to use, high in sensitivity, and compact in structure.

Contents of the invention

The micro-displacement test system is characterized in that: the micro-displacement test system consists of two parts, namely a temperature control system and an imaging system; the temperature control system includes five parts: a spring dynamometer, a thermocouple, a PC, a DC power supply and a switch; One end of the thermocouple is fixed at any position of the spring on the spring dynamometer, and the other end is connected to the PC through the through hole on the bottom plate of the spring dynamometer to collect temperature data; the spring of the spring dynamometer is a shape memory alloy wire, and the spring The dynamometer is connected in series with the light bulb, DC power supply and switch to realize temperature control and provide light source for the imaging system; the imaging system consists of five parts: optical bench, measured structure, light bulb, convex lens, and light screen; the optical bench is divided into two parts : The first is the structure of the lower half of the slide rail; the second is the upper half, which is equipped with a baffle, and the structure to be tested that can transmit light is attached to the baffle; the bulb is fixed on one side of the baffle, and the convex lens and the light screen are located on the baffle in turn. On the other side, and ensure that the light bulb, the structure under test, the convex lens and the light screen are on a horizontal line.

Keep the shape memory alloy wire in a straight line at room temperature; in boiling water, it is tightly wound into a helical shape to form a micro-cylindrical helical tension spring; repeat this many times to stabilize the material properties, that is, as the temperature rises, the alloy wire gradually changes from a straight line to a spring. It is a spring; it gradually returns to its original shape when cooled to room temperature; one end of the shape memory alloy wire is fixed to the pointer, and one end of the shape memory alloy wire is connected to the lifting ring of the spring dynamometer through a section of elastic material; the other end is connected to the spring dynamometer through a section of elastic material After the hook is connected with the base plate of the dynamometer, it can be used to measure the force value and provide tension for the imaging system.

The spring made of the shape memory alloy material passes through the first through hole on the base plate of the spring dynamometer, and the fourth through hole is respectively fixed on the lifting rings and hooks on both sides of the base plate of the spring dynamometer to obtain a shape memory alloy spring dynamometer; The first through hole and the fourth through hole on the base plate are respectively located at the center of both ends of the groove; the second through hole is located at the bottom of the groove, close to the first through hole; the third through hole is located at the bottom of the groove, the second through hole, the fourth through hole between vias.

The first micro-screw is located at the center of the bottom of the baffle, and the second micro-screw is fixed on the baffle opposite to the baffle. The two screws are used to connect the lifting ring and hook of the spring dynamometer inside the optical bench, and ensure that the dynamometer Level with the lower half of the optical bench;

Applying the described micro-displacement testing system is characterized in that:

When the switch of the temperature control system is closed, the DC power supply provides a constant current for the entire system; at this time, the alloy wire inside the shape memory alloy spring dynamometer gradually shrinks as the temperature rises, generating a corresponding pulling force, which pulls the baffle to deflect. The tension value is directly read through the dynamometer panel, and the structure under test is fixed on the baffle, which produces vertical stretching with the movement of the baffle; the thermocouple is connected to the PC to measure and record the temperature of the alloy wire at any time; At the same time, the light bulb lights up, and the measured structure is projected onto the light screen through the convex lens to form an inverted and enlarged real image. The movement of each point on the measured structure during the stretching process is observed on the light screen to realize the displacement measurement and recording of the target point. .

Description of drawings

Figure 1 Schematic diagram of the micro-displacement testing system;

Figure 2 Schematic diagram of the temperature control system;

Figure 3 is a schematic diagram of the imaging system;

Figure 4 Schematic diagram of the working principle of the shape memory alloy wire;

The original state diagram of the spring made in Fig. 5 ( a);

Figure 5 ( b) made of the spring after the temperature rises;

Fig. 6 schematic diagram of optical bench;

Figure 7 is a partial schematic diagram of the micro-displacement testing system;

detailed description

Below in conjunction with embodiment the present invention is described in further detail:

The micro-displacement test system consists of two parts, namely temperature control system and imaging system; ①The temperature control system includes five parts: spring dynamometer, thermocouple, PC, DC power supply and switch; one end of the thermocouple is fixed on the spring dynamometer At any position of the spring on the meter, the other end is connected to the PC through the third through hole 3 on the bottom plate of the spring dynamometer to collect temperature data; the spring of the spring dynamometer is a shape memory alloy wire, and the spring dynamometer and the light bulb , DC power supply and switch are connected in series to realize temperature control and provide light source for the imaging system; the imaging system consists of five parts: the optical bench, the structure to be tested, the bulb, the convex lens, and the optical screen; the optical bench is divided into two parts: one is the lower half The first half is the slide rail structure; the second is the upper half, which is a three-sided structure with the left side long and the right side short, and the top is connected. There is a baffle, and the structure under test that can transmit light is pasted on the baffle; the bulb is fixed on one side of the baffle, and the convex lens and light screen are located on the other side of the baffle in turn, and the light bulb, the structure under test, the convex lens and the light screen are guaranteed The four are on a horizontal line.

Keep the shape memory alloy wire in a straight line at room temperature; in boiling water, it is tightly wound into a helical shape to form a micro-cylindrical helical tension spring; repeat this many times to stabilize the material properties, that is, as the temperature rises, the alloy wire gradually changes from a straight line to a spring. It is a spring; it gradually returns to its original shape when cooled to room temperature; one end of the shape memory alloy wire is fixed to the pointer, and one end of the shape memory alloy wire is connected to the lifting ring of the spring dynamometer through a section of elastic material; the other end is connected to the spring dynamometer through a section of elastic material After the hook is connected with the base plate of the dynamometer, it can be used to measure the force value and provide tension for the imaging system.

The spring made of shape memory alloy material is respectively fixed to the lifting rings and hooks on both sides of the bottom plate of the spring dynamometer through the first through hole 1 and the fourth through hole 4 on the bottom plate of the spring dynamometer, so that the force measurement of the shape memory alloy spring is obtained. Meter; the first through hole and the fourth through hole on the base plate are respectively located at the center of both ends of the groove; the second through hole 2 is located at the bottom of the groove, close to the first through hole 1; the third through hole 3 is located at the second Between the through hole 2 and the fourth through hole 4 .

The lower part of the optical bench is a cuboid with slide rails, made of light-transmitting plastic. The through hole 9 is located at the bottom of the groove close to the baffle plate 8 for passing the wire. The first micro-screw 5 is located at the center of the bottom of the baffle, and the second micro-screw 6 is fixed on the baffle opposite to the baffle. The two screws are used to connect the lifting ring and the hook of the spring dynamometer inside the optical bench, and ensure that the measurement The force gauge is level with the lower half of the optical bench.

When the switch of the temperature control system is closed, the DC power supply provides a constant current for the entire system; at this time, the alloy wire inside the shape memory alloy spring dynamometer gradually shrinks with the increase of temperature, generating a corresponding pulling force, which pulls the baffle 8 to deflect , the tension value is directly read through the dynamometer panel, the structure 7 under test is fixed on the baffle, and the vertical direction is stretched with the movement of the baffle; the thermocouple is connected to the PC, and the alloy wire is measured and recorded at any time temperature; at the same time, the bulb lights up, and the measured structure 7 is projected onto the light screen through a convex lens to form an inverted enlarged real image, and the movement of each point on the measured structure 7 is observed on the light screen during the stretching process, so as to realize the target point. Displacement measurement and recording.

Claims (5)

1. micrometric displacement test macro, is characterized in that: this micrometric displacement test macro is made up of two parts, pointNot temperature control system and imaging system; Temperature control system comprises weight beam, thermocouple, PC, straightStream power supply and switch five parts; Thermocouple one end is fixed on the optional position of weight beam upper spring, anotherOne end is connected into PC through the third through-hole on weight beam base plate, carries out temperature data acquisition; BulletThe spring of spring dynamometer is shape-memory alloy wire, weight beam and bulb, dc source and switch seriesConnection, realizes temperature control, and provides light source for imaging system; Imaging system comprises optical bench, tested knotStructure, bulb, convex lens, optical screen five part compositions; Optical bench divides two parts: the one, and Lower Half slide rail knotStructure; The 2nd, the first half, is provided with baffle plate, can printing opacity be attached on baffle plate by geodesic structure; Bulb is fixed on gearPlate one side, convex lens, optical screen are positioned at baffle plate opposite side successively, and ensure bulb, by geodesic structure, convex lensMirror and optical screen are positioned on a horizontal line.

2. micrometric displacement test macro according to claim 1, is characterized in that: marmemSilk one end and pointer are fixed, and shape-memory alloy wire one end is by one section of elastomeric material and weight beamDrop handle connects; The other end is connected with weight beam hook by one section of elastomeric material.

3. micrometric displacement test macro according to claim 2, is characterized in that: marmemThe spring that material is made is by the first through hole on weight beam base plate, and fourth hole is individually fixed in bulletDrop handle and the hook of spring dynamometer base plate both sides, obtain shape memory alloy spring dynamometer; On base plateOne through hole, fourth hole lays respectively at middle position, groove two ends; The second through hole is positioned at bottom portion of groove, leans onNearly the first through hole; Third through-hole is positioned at bottom portion of groove the second through hole, between fourth hole.

4. micrometric displacement test macro according to claim 3, is characterized in that: miniature screw thread is positioned atBaffle plate bottom center, miniature screw thread is fixed on the baffle plate relative with baffle plate, and two screws are in optical bench insideFor drop handle and the hook of linking springs dynamometer, and ensure dynamometer and optical bench Lower Half level.

5. the method for application micrometric displacement test macro as claimed in claim 1, is characterized in that:

In the time that the switch of temperature control system is closed, dc source provides constant current for whole system; Now,The B alloy wire of shape memory alloy spring dynamometer inside shrinks gradually with the rising of temperature, produces correspondingPulling force, pulls baffle plate deflection, directly reads value of thrust by dynamometer panel, is fixed on by geodesic structureOn baffle plate, produce the stretching of vertical direction with the motion of baffle plate; Thermocouple is led to and is connect PC, surveys at any timeMeasure and record the temperature of B alloy wire; Meanwhile, bulb lights, and is projected optical screen by geodesic structure by convex lensUpper, form the real image that stands upside down and amplify, on optical screen, observe in drawing process by the motion of each point on geodesic structureSituation, the displacement measurement of realize target point and record.