Multi-parameter integrated quality characteristic measuring device

Abstract

This invention provides a multi-parameter integrated quality characteristic measurement device, which can measure multiple quality characteristic parameters in a single clamping. The multi-parameter integrated quality characteristic measurement device includes: a measuring platform assembly, a mass center of mass measurement unit, a moment of inertia measurement unit, a centroid measurement unit, and a measuring fixture; the measuring platform assembly provides a measuring platform and a lifting mechanism for the measuring platform; the measuring fixture is fixed on the measuring platform and used to mount the product under test and change the posture of the product under test; the mass center of mass measurement unit includes three weighing units with lifting functions located below the measuring platform; the moment of inertia measurement unit includes a torsion mechanism for driving the measuring platform to oscillate, a photoelectric period measurement unit for measuring the torsion period of the measuring platform, and a torsion braking mechanism for braking the torsion of the measuring platform; the centroid measurement unit includes a laser displacement measurement unit and an automatic rotary motion structure for driving the product under test to rotate around its own axis.

Description

Technical Field

[0001] This invention relates to a device for measuring quality characteristic parameters, specifically a multi-parameter integrated quality characteristic measuring device, belonging to the field of measurement equipment technology. Background Technology

[0002] Mass, center of mass, and moment of inertia are the most important components of mass characteristic parameters. In the aerospace field, mass is directly related to takeoff load, while the center of mass and moment of inertia are related to the ease of flight trajectory control and attitude adjustment. They are important parameters in the flight control of various weapons and equipment. Product mass characteristic parameters can be obtained through equipment measurement.

[0003] Currently, domestic methods for measuring the geometric centroid and moment of inertia mostly employ a split-system measurement approach. This involves measuring the geometric centroid on a geometric integrated measurement system, the center of gravity on a multi-point weighing platform, and the moment of inertia on a torsion pendulum platform. This method is cumbersome and costly due to the need for multiple equipment changes, and repeated clamping can easily lead to inconsistent reference standards and significant measurement errors.

[0004] With the increasing demands of national defense development, new product models are emerging in greater numbers, and product dimensions vary significantly. In order to save costs, improve measurement efficiency, and reduce equipment space requirements, there is an urgent need for a device that can perform multiple quality characteristic measurements in a single setup to meet the demand for efficient measurement. Summary of the Invention

[0005] In view of this, the present invention provides a multi-parameter integrated quality characteristic measuring device, which can measure multiple quality characteristic parameters in a single clamping, thereby effectively improving measurement efficiency.

[0006] The multi-parameter integrated mass characteristic measurement device includes: a measuring table assembly, a mass center of mass measurement unit, a moment of inertia measurement unit, a centroid measurement unit, and measuring fixtures;

[0007] The measuring platform assembly is used to provide a measuring platform and a measuring platform lifting mechanism;

[0008] The measuring fixture is fixed on the measuring platform and is used to mount the product under test and change the posture of the product under test.

[0009] The mass centroid measuring unit includes three weighing units with lifting functions located below the measuring platform;

[0010] The moment of inertia measurement unit includes a torsion mechanism for driving the measurement platform to torsion, a photoelectric period measurement unit for measuring the torsion period of the measurement platform, and a torsion braking mechanism for braking the torsion of the measurement platform.

[0011] The centroid measurement unit includes a laser displacement measurement unit and an automatic rotational motion structure for driving the measured product to rotate around its own axis; the laser displacement measurement unit includes multiple displacement sensors B installed on the measuring fixture and arranged at intervals along the height direction.

[0012] In a preferred embodiment of the present invention, the torsion mechanism includes: an air-floating turntable, a torsion drive unit, and a torsion bar;

[0013] The stator of the air-bearing turntable is fixed on the main frame of the measuring platform assembly, the rotor is coaxially fixed to the top of the torsion bar, and the bottom of the torsion bar is fixed to the main frame; when measuring the moment of inertia, the measuring platform is placed on the rotor of the air-bearing turntable.

[0014] The torsion drive unit is used to push the measuring platform to twist at a set angle, so that the torsion bar is in a torsion state, and then the air-bearing turntable and the measuring platform are driven to twist back and forth through the torsion bar.

[0015] In a preferred embodiment of the present invention, the torsional braking mechanism includes: a braking cylinder and a friction plate disposed at the telescopic end of the braking cylinder; the cylinder body end of the braking cylinder is mounted on the main frame of the measuring platform assembly, the telescopic end is vertically upward, and the end of the telescopic end is provided with a friction plate; when braking is required, the telescopic end of the braking cylinder extends so that the friction plate at its end contacts the bottom surface of the measuring platform, thereby achieving braking by friction.

[0016] As a preferred embodiment of the present invention, the weighing unit with lifting function includes a weighing sensor and a weighing sensor lifting mechanism. The fixed end of the weighing sensor lifting mechanism is fixed on the main frame of the measuring platform assembly, and the weighing sensor is installed at the end of the telescopic end of the weighing sensor lifting mechanism.

[0017] In a preferred embodiment of the present invention, the measuring platform assembly further includes: a measuring platform displacement monitoring unit;

[0018] The displacement monitoring unit of the measurement platform includes: multiple displacement sensors C distributed along the circumference of the measurement platform for measuring the displacement of the platform at corresponding positions during the lifting process of the measurement platform;

[0019] And multiple displacement sensors A, evenly spaced on the outer side of the outer circumference of the measuring platform, for monitoring the radial displacement of the measuring platform.

[0020] In a preferred embodiment of the present invention, the measuring platform assembly further includes: a measuring platform guiding and positioning unit;

[0021] The measurement platform guiding and positioning unit includes a plurality of ball heads evenly spaced along the circumference on the lower end face of the measurement platform, and ball sockets on the upper surface of the rotor of the air-bearing turntable that correspond one-to-one with the ball heads.

[0022] In a preferred embodiment of the present invention, the measuring fixture includes: an outer frame and an inner frame.

[0023] The tooling frame is fixed to the measuring platform;

[0024] The inner frame of the fixture is connected to the outer frame of the fixture via a pin. The inner frame of the fixture can rotate relative to the outer frame of the fixture around the axial direction of the pin to change the posture of the product being tested.

[0025] The product under test is mounted on the inner frame of the tooling.

[0026] Multiple displacement sensors B are arranged at intervals along the height direction on the inner frame of the tooling to form a laser displacement measurement unit. Each displacement sensor B is set horizontally with its measuring end facing the product being measured, and cross-sectional measurements are performed on the product being measured.

[0027] In a preferred embodiment of the present invention, the automatic rotation motion structure includes a rotary bearing disposed on the inner frame of the tooling. The product under test is mounted on the rotary bearing via a transfer tooling and is supported on the inner frame of the tooling, with the product under test and the rotary bearing being coaxial. The transfer tooling is driven by a rotation drive unit to rotate the product under test around its axis.

[0028] In a preferred embodiment of the present invention, in the laser displacement measurement unit, the height position of each displacement sensor B on the inner frame of the tooling is adjustable, and each displacement sensor B is extendable and retractable in the horizontal direction.

[0029] In a preferred embodiment of the present invention, the measuring platform assembly further includes: a measuring platform protection unit;

[0030] The measurement platform protection unit includes multiple protective frames that are evenly spaced along the circumference of the measurement platform and disposed on the surface of the main frame. The protective frame has a stepped surface on the side opposite to the measurement platform. The vertical part of the stepped surface has a set gap with the outer circumferential surface of the measurement platform, and the horizontal part of the stepped surface has a set gap with the lower surface of the measurement platform.

[0031] Beneficial effects:

[0032] (1) The measuring device of the present invention integrates a mass center of mass measuring unit, a moment of inertia measuring unit, and a centroid measuring unit. All mass characteristic parameters of the product under test can be measured on the same device, and all parameters can be measured by hoisting and clamping the product once, which can effectively improve the measurement efficiency.

[0033] (2) In the measuring device of the present invention, when measuring the moment of inertia, an air bearing is used as a pneumatic turntable. There is only an air film between the stator and the rotor of the pneumatic bearing, which enables frictionless rotation of the rotor relative to the stator and achieves high measurement accuracy.

[0034] (3) In the measuring device of the present invention, the posture of the product under test can be directly changed by measuring fixtures to measure the center of mass and moment of inertia of the product under test in different directions, thereby realizing the measurement of multiple parameters of mass characteristics by one clamping.

[0035] (4) In the centroid measurement unit of the present invention, the height position of each laser displacement sensor (i.e. displacement sensor B) on the inner frame of the tooling is adjustable, and each laser displacement sensor is retractable in the horizontal direction, thereby enabling free adjustment according to the shape of the product being measured.

[0036] (5) The measuring device of the present invention is provided with a friction-based torsional braking mechanism for braking the measuring platform after the rotational inertia measurement is completed, so that the measuring platform stops torsion; the structure is simple and reliable.

[0037] (6) The measuring device of the present invention is equipped with a measuring platform displacement monitoring unit and a measuring platform protection unit to ensure that the measuring platform will not have a large displacement during the measurement process and improve the safety of the measurement process. Attached Figure Description

[0038] Figure 1 This is a diagram showing the composition of the multi-parameter integrated quality characteristic measurement device of the present invention;

[0039] Figure 2 This is a schematic diagram of the multi-parameter integrated quality characteristic measurement device of the present invention;

[0040] Figure 3 This is a schematic diagram of the measurement platform in its lifting state;

[0041] Figure 4 This is a schematic diagram showing the position of the measurement platform during quality measurement.

[0042] Figure 5 This is a schematic diagram illustrating the principle of axial centroid measurement.

[0043] Figure 6 Schematic diagram of the centroid measurement unit layout;

[0044] Figure 7 This is a schematic diagram of the position of the measurement platform when measuring the moment of inertia.

[0045] Among them: 1-product under test, 2-main frame, 3-measuring platform lifting mechanism, 4-displacement sensor A, 5-torsion braking mechanism, 6-measuring platform, 7-torsion bar, 8-weighing unit, 9-air-float turntable, 10-torsion drive unit, 11-tooling outer frame, 12-rotary bearing, 13-pin, 14-weighing sensor, 15-weighing sensor lifting mechanism, 17-rotation drive unit, 18-displacement sensor B, 19-tooling inner frame, 20-ball head. Detailed Implementation

[0046] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0047] Example 1:

[0048] This embodiment provides a multi-parameter integrated mass characteristic measurement device, which can achieve integrated measurement of at least eight independent mass characteristic parameters, including: mass, triaxial center of mass, triaxial moment of inertia, and centroid.

[0049] like Figure 1 and Figure 2 As shown, the mass characteristic measuring device includes: a measuring table assembly, a mass center of mass measuring unit, a moment of inertia measuring unit, a centroid measuring unit, and measuring fixtures;

[0050] The measuring platform assembly includes: main frame 2, measuring platform 6, measuring platform lifting mechanism 3, and measuring and control unit;

[0051] The mass centroid measurement unit includes a weighing unit 8 consisting of a weighing sensor 14 and a weighing sensor lifting mechanism 15;

[0052] The centroid measurement unit includes: an automatic rotational motion structure and a laser displacement measurement unit;

[0053] The moment of inertia measurement unit includes: an air-floating turntable 9, a torsion pendulum drive unit 10, a torsion bar 7, a photoelectric period measurement unit, and a torsion pendulum braking mechanism 5;

[0054] The measuring fixture is used to mount the product under test 1 and can change the attitude of the product under test 1 when performing center of mass measurement and moment of inertia measurement.

[0055] First, define the coordinate system of the measuring device and the coordinate system of the product being measured 1. For the measuring device, define the vertical direction as the X direction, the horizontal direction as the Z direction, and the direction perpendicular to the Z direction in the horizontal plane as the Y direction. The XYZ direction is defined according to the right-hand rule. For the product being measured 1, let its axis be the X direction. When the product being measured 1 is placed vertically (i.e., its axis is along the vertical direction), its Z and Y directions are consistent with the Z and Y directions in the coordinate system of the measuring device.

[0056] The measuring fixture includes an outer frame 11 and an inner frame 19. The inner frame 19 is connected to the outer frame 11 via a pin 13 arranged along the Z direction. The inner frame 19 can rotate relative to the outer frame 11 about the axial direction of the pin 13.

[0057] like Figure 3 As shown, the main frame 2 is the mounting base for the entire device. The measuring platform 6 is located on the main frame 2. The measuring fixture for clamping the product 1 to be measured is placed on the measuring platform 6. Specifically, the outer frame 11 of the fixture is fixedly installed on the measuring platform 6, and the product 1 to be measured is supported on the inner frame 19 of the fixture.

[0058] A measuring platform lifting mechanism 3 is provided between the main frame 2 and the measuring platform 6. In this example, the measuring platform 6 has a disc-shaped structure, and three measuring platform lifting mechanisms 3 are evenly distributed circumferentially below the measuring platform 6 for raising and lowering the measuring platform 6. In this example, the measuring platform lifting mechanism 3 uses a cylinder. The fixed end of the cylinder is fixed to the surface of the main frame 2, and the telescopic end is vertically upward (not connected to the measuring platform 6), used to lift the measuring platform 6 after contacting it. Figure 3 As shown.

[0059] The mass and centroid measurement unit is used to measure the mass and centroid of the product 1 being measured. In this example, a three-point weighing method is used for mass and centroid measurement. Based on this, three weighing units 8 are evenly distributed circumferentially between the main frame 2 and the measuring platform 6. In the weighing unit 8, the weighing sensor 14 is mounted on the main frame 2 via a weighing sensor lifting mechanism 15 (each weighing sensor 14 corresponds to one weighing sensor lifting mechanism 15). In this example, the weighing sensor lifting mechanism 15 is a cylinder, with the fixed end of the cylinder fixed to the surface of the main frame 2, and the weighing sensor 14 mounted on the telescopic end of the cylinder. Figure 4 As shown, during mass measurement, the lifting mechanism 3 of the measuring platform descends to a position where it is not in contact with the measuring platform 6; the load cells 14 are lifted by the lifting mechanism 15 to contact the measuring platform 6; at this time, the measuring platform 6 is supported only by the three load cells 14, and the product 1 to be measured, which is clamped on the measuring fixture, is weighed using the three-point weighing method. During mass measurement, the measuring platform 6 is supported by the three load cells 14, and there is a relatively fixed and accurate geometric positional relationship between the load cells 14 and the measuring platform 6. The mass of the measuring fixture and the product 1 to be measured is completely supported by the three load cells 14, and the measuring fixture, the product 1 to be measured, and the measuring platform 6 also have a definite positional relationship. The mass of the product 1 to be measured is calculated based on the readings of the three load cells 14 before and after loading the product 1 to be measured.

[0060] The measurement of the centroid of the tested product 1 includes the measurement of its Y-axis centroid, Z-axis centroid, and X-axis centroid (i.e., axial centroid) in the coordinate system of the tested product. In this example, the Y-axis and Z-axis centroids of the tested product 1 are measured using the centroid rotation method. Based on this, a rotary bearing 12 is provided on the inner frame 19 of the fixture. The tested product 1 is connected to the rotary bearing 12 through a transition fixture and is supported on the inner frame 19 of the fixture. The tested product 1 and the rotary bearing 12 are coaxial. The rotation drive unit 17 drives the transition fixture, causing the tested product 1 to rotate around its own axis. The rotary bearing 12, the transition fixture, and the rotation drive unit 17 together constitute an automatic rotation motion structure, which is shared with the centroid measurement unit.

[0061] When measuring the Y-axis and Z-axis centroids of the tested product 1, the tested product 1 is rotated by the rotary bearing 12, and data is dynamically collected during the rotation. In this example, data is automatically collected every 1° of rotation. After the tested product 1 has rotated one full circle (i.e., 360°), the measurement results at multiple angles can theoretically yield a series of centroid coordinate values ​​around the rotation axis (i.e., the central axis of the rotary bearing 12). The curve formed by this series of centroid coordinate values ​​is theoretically a circle with radius r centered on the rotation axis, where r is the distance from the centroid to the rotation axis.

[0062] like Figure 5 As shown, the measurement of the axial center of mass (i.e., the X-axis center of mass) is based on the principle of the three-point weighing method. When the product 1 to be measured is rotated to an axially horizontal position through the inner frame 19 of the tooling, the axial center of mass is directly measured twice, in the forward direction and in the reverse direction, and the direct measurement of the axial center of mass is converted into the relative offset of the two axial centers of mass, so as to calculate the distance of the axial center of mass from the rotation axis.

[0063] The centroid measurement unit is used to measure the centroid of the product 1 being measured. By measuring the centroid and combining the results with the centroid measurement, the lateral deviation of the centroid of the product 1 being measured (i.e., the deviation of the centroid from the centroidal axis) can be obtained; for example... Figure 6As shown, the centroid measurement unit includes an automatic rotational motion structure (i.e., the aforementioned rotary bearing 12, adapter fixture, and rotary drive unit 17) and a laser displacement measurement unit. The automatic rotational motion structure drives the product under test 1 to rotate around its axis. The laser displacement measurement unit consists of multiple displacement sensors B18 spaced apart along the height direction on the inner frame 19 of the fixture, which are used to measure the cross-section. In this example, the displacement sensors B18 are laser displacement sensors, and three laser displacement sensors are spaced apart along the height direction on the inner frame 19 of the fixture. Each laser displacement sensor is horizontally positioned with its measuring end facing the product under test 1. When the length of the product under test 1 is large, a displacement sensor bracket can be connected to the inner frame 19 of the fixture to ensure that multiple laser displacement sensors are spaced apart along the height direction of the product under test 1. The height position of each laser displacement sensor on the inner frame 19 of the fixture is adjustable, and each laser displacement sensor is horizontally extendable, thus allowing for free adjustment according to the shape of the product under test 1.

[0064] The automatic rotating motion structure drives the tested product 1 to rotate one revolution. The time for one revolution is pre-calibrated. The rotation angle of the tested product 1 can be calculated from the rotation time. Combined with the displacement signals at each cross section of the tested product 1 synchronously collected by the laser displacement measurement unit, the data required for centroidal axis fitting can be obtained. Then, the centroidal axis is obtained by fitting using the least squares method. The centroidal coordinates of the cross section where the centroidal axis is located can be obtained through the intersection of the centroidal axis and the cross section where the X-axis centroid is located. Then, the lateral centroidal deviation of the cross section where the X-axis centroid is located can be obtained.

[0065] The moment of inertia measurement unit is used to measure the moment of inertia of the tested product 1 in three directions (XYZ directions). A torsion bar 7 is installed inside the main frame 2, coaxially positioned below the measurement platform 6. An air-bearing turntable 9 is coaxially positioned between the measurement platform 6 and the torsion bar 7. The air-bearing turntable 9 uses a pneumatic bearing; only an air film exists between the stator and rotor of the pneumatic bearing, thus enabling frictionless rotation of the rotor relative to the stator. The stator of the pneumatic bearing is fixed to the main frame 2, the rotor is coaxially fixed to the top of the torsion bar 7, and the bottom of the torsion bar 7 is fixed to the main frame 2. The measurement platform 6 is placed on the rotor of the pneumatic bearing (there is no connection between the two; it is only placed on the rotor). The torsion bar 7 is a flexible rod, allowing the rotor of the pneumatic bearing to only twist. The torsion drive unit 10 is used to push the measuring platform 6 to rotate at an initial angle, so that the torsion bar 7 is in a torsional state. The torsion bar 7 then drives the air-bearing turntable 9 and the measuring platform 6 to reciprocate. The torsion period of the measuring platform 6 is measured by the photoelectric period measurement unit, thereby obtaining the moment of inertia in the rotational direction. The photoelectric period measurement unit includes a photoelectric sensor and a pendulum needle. The pendulum needle is mounted on the lower surface of the measuring platform 6, and the photoelectric sensor is fixed to the main frame 2. When the measuring platform 6 reciprocates, it drives the pendulum needle to swing back and forth within the detection area of ​​the photoelectric sensor. The photoelectric sensor receives a trigger signal, and thus the oscillation period is measured.

[0066] like Figure 7 As shown, when the moment of inertia needs to be measured, the measuring platform 6 is lowered onto the air-floating turntable 9. At this time, the measuring platform 6 is not in contact with the measuring platform lifting mechanism 3 and the weighing unit 8. The torsion drive unit 10 includes a push cylinder and a push rod or push block set on the lower surface of the measuring platform 6. By pushing the push cylinder to push the push rod or push block, the measuring platform 6 is twisted at an initial angle of about 2°, thereby putting the torsion bar 7 in a torsion state. After the push cylinder is de-aired, its push rod quickly returns to its original position, and the measuring platform 6 swings back and forth at a slower speed due to the load of the moment of inertia, thus completing one drive action.

[0067] The inner frame 19 of the tooling drives the tested product 1 to rotate, thereby changing the posture of the tested product 1 and measuring the rotational inertia in different directions. For example, when the axis of the tested product 1 is vertically upward (i.e., the X-axis of the tested product 1 is coaxial with the rotary bearing 12), the rotational inertia in the X direction is measured; when the Y-axis of the tested product 1 is vertically upward, the rotational inertia in the Y direction is measured; and when the Z-axis of the tested product 1 is vertically upward, the rotational inertia in the Z direction is measured.

[0068] When measuring the center of mass, the measuring platform 6 is lifted by the measuring platform lifting mechanism 3 so that it does not come into contact with the rotor of the air-float turntable 9.

[0069] The torsional braking mechanism 5 is used to brake the measuring platform 6 after the rotational inertia measurement is completed, so that the measuring platform 6 stops twisting. In this example, the torsional braking mechanism 5 includes a brake cylinder and a friction plate disposed at the end of the extension and retraction end of the brake cylinder; the cylinder body end of the brake cylinder is fixed on the main frame 2, the extension and retraction end is vertically upward, and the end of the extension and retraction end is provided with a friction plate; when braking is required after the measurement is completed, the extension and retraction end of the brake cylinder is controlled to extend so that the friction plate at its end contacts the bottom surface of the measuring platform 6, thereby achieving braking by friction.

[0070] The measurement and control unit located inside the main frame 2 is used to receive monitoring data from each sensor (including the weighing sensor 14 and each displacement sensor B) in the measuring device, and to control the measuring platform lifting mechanism 3, the weighing sensor lifting mechanism 15, the automatic rotation motion structure, the torsion drive unit 10 and the torsion braking mechanism 5.

[0071] In summary, in this example, measurement platform 6 has the following states during the measurement process:

[0072] (1) The state of the installation of measuring fixture and the product under test 1: the lifting mechanism 15 of the three weighing sensors falls down, the lifting mechanism 3 of the three measuring platforms rises and lifts the measuring platform 6, and the measuring platform 6 is separated from the air-float turntable 9;

[0073] (2) Mass center of mass measurement status: The lifting mechanism 3 of the three measuring platforms is lowered, and the lifting mechanism 15 of the three weighing sensors is raised to support the measuring platform 6. The measuring platform 6 is separated from the air-float turntable 9 and is only supported by three weighing points. When measuring the center of mass in the Y and Z directions, the product 1 being measured is installed vertically. When measuring the center of mass in the X direction, the inner frame 19 of the tooling is rotated 90 degrees before measurement. At this time, the axis of the product 1 being measured is along the horizontal direction.

[0074] (3) Rotational inertia measurement state: The lifting mechanisms 3 of the three measuring platforms and the lifting mechanisms 15 of the three weighing sensors are all lowered, and the measuring platform 6 is placed on the air-floating turntable 9. It can rotate with the air-floating turntable 9 and the rotational inertia is measured by the torsion bar method.

[0075] (4) Placement state: When no measurement is required, i.e. when the power and air supply to the device are cut off, the three measuring platform lifting mechanisms 3 and the three weighing sensor lifting mechanisms 15 all fall down, and the measuring platform 6 is supported on the air flotation turntable 9.

[0076] Example 2:

[0077] Based on the above embodiment 1, the measuring platform assembly further includes: a measuring platform displacement monitoring unit; the measuring platform displacement monitoring unit includes a displacement sensor C disposed next to each weighing sensor 14 for monitoring the displacement of the measuring platform 6 at the corresponding position during the lifting process of the measuring platform 6; by comparing the measured values ​​of the three displacement sensors C, the synchronicity of the lifting process of the measuring platform 6 and the levelness of the measuring platform 6 are ensured.

[0078] In addition, displacement sensors A4 are installed on both opposite sides along the Z direction and both opposite sides along the Y direction on the outer circumference of the measuring platform 6. Figure 2 The displacement sensor A4 shown is used to monitor the displacement of the measuring platform 6 along the Z and Y directions.

[0079] Example 3:

[0080] Based on the above embodiment 1 or embodiment 2, the measuring platform assembly further includes: a measuring platform guiding and positioning unit; the measuring platform guiding and positioning unit includes three ball heads 20 evenly spaced along the circumference on the lower end face of the measuring platform 6 and ball sockets on the upper surface of the rotor of the air-bearing turntable 9 corresponding to the three ball heads 20; during the lifting and lowering process of the measuring platform, the measuring platform 6 is positioned by the cooperation of the ball sockets and ball heads.

[0081] Example 4:

[0082] Based on the above embodiment 1, embodiment 2, or embodiment 3, the measuring platform assembly further includes: a measuring platform protection unit; the measuring platform protection unit includes multiple protective frames disposed on the surface of the main frame 2 and evenly spaced along the circumference of the measuring platform 6; the side of the protective frame opposite to the measuring platform 6 has a stepped surface, the vertical portion of the stepped surface has a set gap with the outer circumferential surface of the measuring platform 6, and the horizontal portion of the stepped surface has a set gap with the lower surface of the measuring platform 6; in this example, a gap of no more than 10mm is left in both the horizontal and vertical directions, which eliminates unpredictable dangers such as overturning and side slipping of the measuring platform 6 in extreme cases, ensuring the absolute safety of the product.

[0083] Preferably, four protective frames are provided on the measuring platform 6. The four protective frames are located on two opposite sides of the measuring platform 6 along the Z direction and two opposite sides along the Y direction, respectively. Thus, the four displacement sensors in the measuring platform displacement monitoring unit used to monitor the displacement of the measuring platform 6 along the Z and Y directions can be installed on the protective frames at the corresponding positions.

[0084] Example 5:

[0085] This embodiment provides a method for measuring multiple parameters of the quality characteristics of the product under test 1 using the integrated measuring device described in Embodiments 1-4 above.

[0086] This measuring device can achieve the full measurement of mass, triaxial center of mass, triaxial moment of inertia and centroid in a single clamping operation; without considering the product hoisting time, the entire measurement process takes about 30 minutes.

[0087] The entire measurement process is divided into two stages: skin measurement (i.e., without the product under test 1 installed) and "skin + product" measurement (i.e. with the product under test 1 installed). The measurement process is the same in both stages. The measurement process after installing the product under test 1 will be described in detail below.

[0088] When installing the product under test 1, first start the measuring platform lifting mechanism 3, and use the measuring platform lifting mechanism 3 to lift the measuring platform 6; the product under test 1 and the tooling inner frame 19 are both in a vertical self-rotation state of 0°.

[0089] After the product under test 1 is installed, the weighing unit 8 is first lifted to the position where it contacts the measuring platform 6, and then the measuring platform lifting mechanism 3 is lowered. At this time, the weighing unit 8 can be used for weighing. The rotating drive unit 17 drives the rotating bearing 12 to rotate, causing the product under test 1 to rotate around its axis for one revolution, so as to measure the center of mass in the Y and Z directions.

[0090] During the Y-axis and Z-axis centroid measurement process, that is, during the rotation of the product under test 1 around its axis, the measurement is performed by the laser displacement measurement unit. Thus, the centroid measurement can be performed simultaneously with the Y-axis and Z-axis centroid measurements, that is, the centroid measurement and the Y-axis and Z-axis centroid measurements are performed synchronously, resulting in high measurement efficiency.

[0091] After the Y-axis and Z-axis center of mass measurements are completed, the X-axis moment of inertia is measured: at this time, the weighing unit 8 is lowered so that the measuring platform 6 rests on the rotor of the air-float turntable 9; the torsion drive unit 10 is activated to make the measuring platform 6 reciprocate torsion to measure the X-axis moment of inertia; after the X-axis moment of inertia measurement is completed, the measuring platform 6 is braked by the torsion brake 5 mechanism. After the measuring platform 6 is braked, the measuring platform lifting mechanism 3 is activated to lift the measuring platform 6.

[0092] Then, the first measurement of the X-axis center of mass (i.e., the forward measurement) is performed: the inner frame 19 of the tooling is adjusted to a horizontal state, that is, the axis of the product being measured 1 is horizontal (and the Y-axis of the product being measured 1 is vertical); the weighing unit 8 is lifted to a position in contact with the measuring platform 6, and then the measuring platform lifting mechanism 3 is lowered; at this time, the weighing unit 8 can be used to weigh, thereby performing the forward measurement of the X-axis center of mass.

[0093] After the first X-axis center of mass measurement, the Y-axis moment of inertia is measured: the weighing unit 8 is lowered so that the measuring platform 6 rests on the rotor of the air-bearing turntable 9, and the torsion drive unit 10 is activated to make the measuring platform 6 reciprocate torsion to measure the Y-axis moment of inertia; after the Y-axis moment of inertia measurement is completed, the measuring platform 6 is braked by the torsion braking mechanism 5. After the measuring platform 6 is braked, the measuring platform lifting mechanism 3 is activated to lift the measuring platform 6.

[0094] Then, the Z-axis rotational inertia is measured: the test product 1 is controlled to rotate 180° by an automatic rotational motion structure, so that the Z-axis of the test product 1 coincides with the axial direction of the rotary bearing 12; then, the measuring platform lifting mechanism 3 is lowered, so that the measuring platform 6 rests on the rotor of the air-floating turntable 9; the torsion pendulum drive unit 10 is activated, so that the measuring platform 6 reciprocates torsion pendulum to measure the Z-axis rotational inertia; after the Z-axis rotational inertia measurement is completed, the measuring platform 6 is braked by the torsion pendulum braking mechanism 5. After the measuring platform 6 is braked, the measuring platform lifting mechanism 3 is activated to lift the measuring platform 6.

[0095] Then, perform the second measurement of the X-axis center of mass (i.e., reverse measurement): Rotate the inner frame 19 of the fixture 180° around the pin 13 at its connection with the outer frame 11 of the fixture. At this time, the axis of the product 1 being measured is still in the horizontal direction, but the positions of the two ends of the axis are reversed. Lower the lifting mechanism 3 of the measuring platform so that the measuring platform 6 falls on the air-float turntable 9. Then, use the weighing unit 8 to lift the measuring platform 6 so that it does not contact the air-float turntable 9. At this time, the weighing unit 8 can be used to weigh (perform the second measurement of the X-axis center of mass). After the measurement is completed, lower the weighing unit 8 so that the measuring platform 6 falls on the air-float turntable 9 and is repositioned. Then, start the lifting mechanism 3 of the measuring platform to lift the measuring platform 6.

[0096] Finally, the state is reset.

[0097] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A multi-parameter integrated quality characteristic measurement device, characterized in that: include: Measuring table assembly, mass center of mass measuring unit, moment of inertia measuring unit, centroid measuring unit, and measuring fixture; The measuring platform assembly is used to provide a measuring platform and a measuring platform lifting mechanism; The measuring fixture is fixed on the measuring platform and is used to install the product under test and change the posture of the product under test in order to measure the center of mass and moment of inertia of the product under test in different directions, thereby realizing the measurement of multiple parameters of mass characteristics through a single clamping. The mass centroid measuring unit includes three weighing units with lifting functions located below the measuring platform; The moment of inertia measurement unit includes a torsion mechanism for driving the measurement platform to torsion, a photoelectric period measurement unit for measuring the torsion period of the measurement platform, and a torsion braking mechanism for braking the torsion of the measurement platform. The centroid measurement unit includes a laser displacement measurement unit and an automatic rotary motion structure for driving the product under test to rotate around its own axis; the laser displacement measurement unit includes multiple displacement sensors mounted on the measuring fixture and arranged at intervals along the height direction. The torsion mechanism includes: an air-float turntable, a torsion drive unit, and a torsion bar; The stator of the air-bearing turntable is fixed on the main frame of the measuring platform assembly, the rotor is coaxially fixed to the top of the torsion bar, and the bottom of the torsion bar is fixed to the main frame; when measuring the moment of inertia, the measuring platform is placed on the rotor of the air-bearing turntable. The torsion drive unit is used to push the measuring platform to twist at a set angle, so that the torsion bar is in a torsion state, and then the air-bearing turntable and the measuring platform are driven to twist back and forth through the torsion bar; The torsion drive unit includes a push cylinder and a push rod or push block disposed on the lower surface of the measuring platform. By pushing the push rod or push block with the push cylinder, the measuring platform is twisted at an initial angle, thereby putting the torsion bar in a torsion state. After the push cylinder is de-aired, its push rod quickly returns to its original position, and the measuring platform swings back and forth at a slower speed due to the rotational inertia load, thus completing one drive action. The torsional braking mechanism includes a brake cylinder and a friction plate disposed at the end of the extension and retraction end of the brake cylinder. The cylinder body end of the brake cylinder is mounted on the main frame of the measuring platform assembly, the extension and retraction end is vertically upward, and the end of the extension and retraction end is provided with a friction plate. When braking is required, the extension and retraction end of the brake cylinder extends so that the friction plate at its end contacts the bottom surface of the measuring platform, thereby achieving braking by friction.

2. The multi-parameter integrated quality characteristic measurement device as described in claim 1, characterized in that: The weighing unit with lifting function includes a weighing sensor and a weighing sensor lifting mechanism. The fixed end of the weighing sensor lifting mechanism is fixed on the main frame of the measuring platform assembly, and the weighing sensor is installed at the end of the telescopic end of the weighing sensor lifting mechanism.

3. The multi-parameter integrated quality characteristic measurement device as described in claim 1, characterized in that: The measuring station assembly also includes: a measuring platform displacement monitoring unit; The displacement monitoring unit of the measurement platform includes: multiple displacement sensors distributed circumferentially along the measurement platform, used to measure the displacement at corresponding positions during the lifting process of the measurement platform; And multiple displacement sensors evenly spaced on the outer side of the outer circumference of the measuring platform for monitoring the radial displacement of the measuring platform.

4. The multi-parameter integrated quality characteristic measurement device as described in claim 1, characterized in that: The measuring station assembly further includes: a measuring platform guiding and positioning unit; The measurement platform guiding and positioning unit includes a plurality of ball heads evenly spaced along the circumference on the lower end face of the measurement platform, and ball sockets on the upper surface of the rotor of the air-bearing turntable that correspond one-to-one with the ball heads.

5. The multi-parameter integrated quality characteristic measurement device as described in claim 1, characterized in that: The measuring fixture includes: an outer frame and an inner frame; The tooling frame is fixed to the measuring platform; The inner frame of the fixture is connected to the outer frame of the fixture via a pin. The inner frame of the fixture can rotate relative to the outer frame of the fixture around the axial direction of the pin to change the posture of the product being tested. The product under test is mounted on the inner frame of the tooling. Multiple displacement sensors are arranged at intervals along the height direction on the inner frame of the tooling to form a laser displacement measurement unit. Each laser displacement sensor is set horizontally with its measuring end facing the product being measured, and cross-sectional measurements are performed on the product being measured.

6. The multi-parameter integrated quality characteristic measurement device as described in claim 5, characterized in that: The automatic rotation motion structure includes a rotary bearing mounted on the inner frame of the fixture. The product under test is mounted on the rotary bearing via a transfer fixture, and then supported on the inner frame of the fixture. The product under test is coaxial with the rotary bearing. The transfer fixture is driven by a rotation drive unit to rotate the product under test around its axis.

7. The multi-parameter integrated quality characteristic measurement device as described in claim 5, characterized in that: In the laser displacement measurement unit, the height position of each laser displacement sensor on the inner frame of the tooling is adjustable, and each laser displacement sensor is extendable and retractable in the horizontal direction.

8. The multi-parameter integrated quality characteristic measurement device as described in claim 1, characterized in that: The measuring station assembly also includes: a measuring platform protection unit; The measurement platform protection unit includes multiple protective frames that are evenly spaced along the circumference of the measurement platform and disposed on the surface of the main frame. The protective frame has a stepped surface on the side opposite to the measurement platform. The vertical part of the stepped surface has a set gap with the outer circumferential surface of the measurement platform, and the horizontal part of the stepped surface has a set gap with the lower surface of the measurement platform.

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