TWI768573B - Vibration force measuring device - Google Patents

Abstract

A vibration force measuring device includes a measuring platform, a lifter, a sensor, and a connector. The measuring platform has a carrying surface for carrying a device under test. The lifter is configured to lift up the measuring platform to separate the measuring platform from an upper surface of the lifter. The sensor is configured to sense vibration produced by the device under test during operation. The connector connects the measuring platform and the sensor, and is configured to transmit the vibration of the device under test to the sensor. The connector has different rigidity on different directions.

Description

Vibration force measuring device

The present disclosure relates to a force measuring device, and more particularly, to a vibration force measuring device.

Rotating machinery is widely used in electromechanical systems in various fields. In order to solve the problem of unbalanced vibration generated by rotating machinery during operation, the industry's conventional technology uses a balance corrector to measure the unbalanced mass and its existing position, and uses subtraction or addition to correct the mass to solve the rotor unbalance. Vibration problem.

In principle, the dynamic balancing machine can be divided into a soft dynamic balancing machine and a hard dynamic balancing machine. Due to the complicated operation of soft balancing machines, they are relatively rare in the market. The rigid balancing machine uses piezoelectric force sensors to directly process the vibration force. For the processing of double-sided and single-sided dynamic balancing, compared with the complex plane separation method of the soft balancing machine, the hard balancing machine can provide a faster balancing processing method.

The balancing machine mainly measures the unbalance of the rotor through the centrifugal force generated when the rotor rotates. The hard bearing balancing machine can directly measure the centrifugal force, and then use the centrifugal force to calculate the unbalance of the rotor. The soft bearing balancing machine measures the vibration of the rotor when it rotates, so it is necessary to add a test weight to convert it into the unbalance of the rotor.

The hard support balancing machine is more suitable for rotors with large mass and large initial unbalance. The soft support balancing machine is more suitable for lighter rotors and rotors with very high working speeds. Because lighter rotors and high-speed rotors are widely used in various small household appliances, they are in great demand in the market.

For various small cooling fans used in electronics, automobiles, medical care, home appliances and other fields, the precision error of the hard support balancing machine for the trace vibration force is too large, and the natural frequency of the high-speed rotor is easy to be too close or lower. cannot be measured. The soft support balancing machine developed for the fan uses an accelerometer to measure the vibration, which cannot meet the needs of the production line to directly detect the centrifugal force. At the same time, there is an error in converting the detected vibration into centrifugal force. In addition, the existing soft support balancing machine specifications have poor sensitivity and resolution for the measurement of trace vibration forces, and cannot accurately and directly present the vibration force data of small fans required by the production line, so they cannot be further applied to product classification.

The biggest problem of the existing fan vibration measurement system for the quality control of the manufacturer's production line is that the installation and measurement time is too long, and the detection amount per unit time cannot exceed that of manual work.

Therefore, one purpose of the present disclosure is to provide a vibration force measurement device, which has real-time force sensing, data quantification and classification, and fast full inspection capabilities, and the device is easy to erect and install, so it can solve the problem of commercial rotor vibration detection systems. In the production line of the product to be tested with high-speed rotating components such as fans, the measurement time is too long and the full inspection cannot be performed.

Another object of the present disclosure is to provide a vibration force measuring device, which can use a load cell sensor as a vibration sensor, so that the force change of the object to be measured can be directly measured when it is running data, and has the advantages of low cost, easy access, and complete specifications, especially for the measurement range of trace vibration forces below 10N.

Another object of the present disclosure is to provide a vibration force measurement device, the measurement platform of which can be supported by a frictionless or low-friction lifting device, so that external interference can be blocked, and the vibration force measurement of the object to be measured can be effectively improved. sensitivity.

Another object of the present disclosure is to provide a vibration force measuring device, the connecting member of which can adopt a flexible hinge, so as to achieve isolation of interference sources outside a single plane, so that the change of the horizontal vibration force of the object to be measured can be accurately measured .

According to the above-mentioned purpose of the present disclosure, a vibration force measuring device is provided, which is suitable for measuring an object to be tested with a high-speed rotating element. The vibration force measuring device includes a measuring platform, a lifting device, a sensor, and a connecting piece. The measuring platform has a bearing surface to carry the object to be measured. The lifting device is configured to lift the measurement platform off the upper surface of the lifting device. The sensor is configured to sense the amount of vibration generated when the object to be tested is running. The connecting piece connects the measuring platform and the sensor, and is configured to transmit the vibration of the object to be measured to the sensor. The rigidity of the connector in different directions is not the same.

According to an embodiment of the present disclosure, the above-mentioned measuring platform includes a jig, and the jig is configured to fix the object to be measured on the measuring platform.

According to an embodiment of the present disclosure, the above-mentioned lifting device is an air bearing, and the air bearing can use gas to float the measuring platform away.

According to an embodiment of the present disclosure, the aforementioned lifting device includes at least three balls protruding from the upper surface of the lifting device, and the balls are configured to lift the measuring platform away from the upper surface of the lifting device.

According to an embodiment of the present disclosure, the above-mentioned lifting device further includes at least one magnetic attraction element, and the at least one magnetic attraction element is configured to exert a magnetic attraction force on the measurement platform.

According to an embodiment of the present disclosure, the above-mentioned lifting device further includes a base, the sensor is fixed on the base, and the natural frequency of the system composed of the lifting device, the sensor, and the connecting piece is higher than that of the object to be tested. rotation frequency.

According to an embodiment of the present disclosure, the rigidity of the above-mentioned connecting element in a plane direction parallel to the bearing surface of the measuring platform is greater than the rigidity in a plane direction perpendicular to the plane direction.

According to an embodiment of the present disclosure, the above-mentioned connecting element is a flexible hinge.

According to an embodiment of the present disclosure, the aforementioned connector includes a metal sheet.

The hard support dynamic balancing technology is suitable for measuring the rotor whose vibration is less than the natural frequency of its system, so it is more suitable for the larger rotor workpiece to directly measure the centrifugal force. The soft support dynamic balancing technology is suitable for measuring the rotor whose vibration is greater than the natural frequency of the system, so it is more suitable for measuring the vibration displacement of small and high-speed rotor workpieces. The present disclosure hereby provides a vibration force measuring device, which is suitable for the vibration frequency of the object to be measured which is lower than the natural frequency of the supporting system of the measuring device.

Please refer to FIG. 1 to FIG. 3 , which are respectively a three-dimensional schematic view, a top view schematic view, and a side view schematic view of a vibration force measuring device according to an embodiment of the present disclosure. The vibration force measuring device 100a can be used to measure the vibration force generated by the object to be tested with a high-speed rotating element during operation. The DUT can be a motor or a fan, such as a thin cooling fan or a thin motor. For example, the rotation radius of the fan is more than three times larger than the axial thickness of the fan. The centrifugal force of a thin fan is greater than that of a non-thin fan. Therefore, the shaking force of the thin fan is mainly the radial centrifugal force generated by the offset of the center of mass of the fan when it rotates. The vibration force measuring device 100 a may mainly include a measuring platform 110 , a lifting device 120 , a sensor 130 , and a connecting member 140 .

The measurement platform 110 has a bearing surface 112 , and the bearing surface 112 can carry the object to be measured thereon. The bearing surface 112 may, for example, extend horizontally. 2 and 3, in some exemplary examples, the horizontal plane is an XY plane defined by the coordinate axis X and the coordinate axis Y, and the bearing surface 112 is substantially parallel to the XY plane during measurement. The coordinate axis Z is perpendicular to the XY plane, that is, the coordinate axis X, the coordinate axis Y, and the coordinate axis Z are perpendicular to each other. The measurement platform 110 is preferably made of a light-weight plate, so as to reduce the influence of the vibration signal of the object to be measured.

In some examples, metrology platform 110 may include fixture 114 . The fixture 114 can protrude from the bearing surface 112 of the measurement platform 110 . Thereby, the fixture 114 can clamp and fix the object to be measured on the bearing surface 112 of the measurement platform 110 . In other examples, the measurement platform 110 can also use other fixing elements, such as fasteners, locks, magnetic parts, or vacuum suction parts, etc., to clamp and fix the object to be measured on the bearing surface of the measurement platform 110 112 and above.

The measuring platform 110 is disposed above the upper surface 122 of the lifting device 120 . The lifting device 120 can lift the measuring platform 110 away from the upper surface 122 of the lifting device 120 , thereby greatly reducing the frictional force between the measuring platform 110 and the lifting device 120 . The upper surface 122 of the lifting device 120 is an XY plane. By reducing the friction force between the measuring platform 110 and the lifting device 120 , the interference of the friction force on the vibration force signal of the object to be measured in the XY plane can be avoided. In this embodiment, the lifting device 120 is an air bearing. In some examples, as shown in FIG. 3 , the lifting device 120 can include a base 124 and one or more air-floating parts 126 , wherein the air-floating parts 126 can be protruded on the base 124 . In some exemplary examples, the air floating portion 126 may be embedded in the base 124 , and the top surface of the air floating portion 126 may be flush with the top surface of the base 124 or may be lower than the top surface of the base 124 . The air floating portion 126 of the lifting device 120 can float the measurement platform 110 away from the upper surface 122 of the lifting device 120 by using gas.

The sensor 130 is mainly used for sensing the vibration amount generated when the object to be tested is running. In this embodiment, the sensor 130 is indirectly connected to the measurement platform 110 . The sensor 130 can be, for example, fixed on the base 124 of the lifting device 120, or can also be fixed on an external support structure. The sensor 130 may be, for example, a load cell sensor, a piezoelectric force sensor, or a capacitive force sensor. The sensor 130 can also be a displacement sensor, an acceleration sensor, etc., such as a linear differential transformer (LVDT), a capacitive displacement device, an optical scale, a magnetic scale, and an accelerometer. As long as the sensor can measure physical quantities such as force, displacement, or acceleration generated by vibration, it is within the scope of implementation of the sensor of the present disclosure. In some exemplary examples, the sensor 130 can be a load cell sensor, because the load cell sensor can directly measure the force change data, especially for the micro vibration force measurement range below 10N, and has low cost, The advantages of easy access and complete specifications.

The connector 140 connects the measurement platform 110 and the sensor 130 . Changes in force on the measurement platform 110 are transmitted to the sensor 130 by this connector. That is, the connecting member 140 can transmit the vibration amount generated when the object to be measured runs on the measurement platform 110 to the sensor 130 . In this embodiment, since the sensor 130 is fixed to the lifting device 120 , the natural frequency of the system composed of the lifting device 120 , the sensor 130 , and the connecting member 140 must be higher than the rotation frequency of the object to be tested in design. .

The rigidity of the connecting member 140 is different in different directions, so as to filter out the force interference other than the desired direction. In some examples, the rigidity of the connecting member 140 in a plane direction parallel to the bearing surface 112 of the measurement platform 110 is greater than the rigidity in a plane direction perpendicular to the plane direction. For example, the plane direction parallel to the bearing surface 112 of the measurement platform 110 is the XY plane, and the rigidity of the connecting member 140 on the XY plane is greater than the rigidity on the coordinate axis Z, so as to filter out vibration force signals outside the XY plane. The specific directional rigidity of the connector 140 is used to filter out the force interference outside the XY plane. In some examples, the connector 140 is a flexible hinge. In some exemplary examples, the connecting member 140 includes a metal sheet, the metal sheet extends horizontally on the XY plane defined by the X coordinate axis and the Y coordinate axis, and the rigidity of the metal sheet on the XY plane is greater than the rigidity of the metal sheet on the coordinate axis Z, To filter out the vibration force signal outside the XY plane. The connecting piece can be made of thin metal sheets of different thicknesses according to the object to be measured, such as a fan. For example, for a fan with a diameter of 50 mm and a rotational speed of 7600 rpm, a metal sheet with a thickness of 0.1 mm can be used as the connecting member 140 .

Since the rotor type of most cooling fans is that the rotating diameter is 3 to 10 times larger than the axial size, the unbalance of the fan rotor during operation can be regarded as single-plane vibration, and the main part is radial vibration. Therefore, this embodiment is simplified to only measure the radial vibration force on the XY plane of the object under test with high-speed rotating elements, such as a fan.

The vibration force measuring device 100a can use the load cell sensor as the sensor 130, and can directly measure the force change data of the object to be tested when it is running, so it has real-time force sensing, data quantification and classification, and fast full detection ability. For example, the upper and lower boundary values of the vibration force of the object to be tested can be set, so that the quality of the object to be tested can be quickly detected according to the measurement data. In addition, the vibration sensing force can be classified, whereby the product quality of the object to be tested can be quickly classified according to the measurement data.

In addition, the low price of the load cell sensor can reduce the equipment cost of the vibration force measuring device 100a. The measurement platform 110 is supported by a frictionless air-floating lifting device 110 , and the selection of the flexible connecting member 140 can achieve isolation of interference sources outside a single plane. Therefore, the vibration force measuring device 100a can accurately and sensitively measure the real vibration force of the object to be measured, and is especially suitable for small and precise heat dissipation of electronic, automotive, and medical applications where the vibration force magnitude is 0.001N~0.1N. fan.

The data measured by the vibration force measuring device 100a can be further characterized and analyzed through frequency domain, time domain, or model, so as to be applied to subsequent intelligent management.

The lifting device of the present disclosure is not limited to the above-mentioned air-floating element, and a low-friction element can also be used as the lifting device. Please refer to FIG. 4 , which is a schematic side view of a vibration force measuring device according to another embodiment of the present disclosure. The components and structure of the vibration force measuring device 100b of this embodiment are substantially the same as those of the vibration force measuring device 100a. Low friction element.

In some examples, the lifting device 150 may primarily include a base 154 and a plurality of balls 156 . The balls 156 are rotatably disposed in the base 154 and protrude from the upper surface 152 of the lifting device 150 . The measurement platform 110 is placed on the upper surface 152 of the lifting device 150 . The balls 156 can support the measuring platform 110 and lift the measuring platform 110 away from the upper surface 152 of the lifting device 150 . The number of the balls 156 is equal to or greater than three, so as to support the measurement platform 110 stably.

Using the balls 156 to lift the measuring platform 110 can greatly reduce the contact area between the measuring platform 110 and the lifting device 150 , thereby effectively reducing the friction between the measuring platform 110 and the lifting device 150 . The low friction design between the measuring platform 110 and the lifting device 150 can avoid the interference of the friction between the two to the vibration force signal of the object to be measured in the XY plane.

Please continue to refer to FIG. 4 , in some exemplary examples, the lifting device 150 may optionally include one or more magnetic attraction elements 158 . In such an example, the metrology platform 110 may comprise a ferromagnetic material. The magnetic attraction element 158 can apply a magnetic force to the measuring platform, so as to exert a pre-pressure on the measuring platform 110 toward the upper surface 152 of the lifting device 150 . The pre-pressure can prevent the measurement platform 110 from jumping off due to excessive shaking force generated when the object to be tested is running, so the lifting device 150 can stably support the measurement platform 110 during the measurement process.

As can be seen from the above-mentioned embodiments, one of the advantages of the present disclosure is that the vibration force measurement device of the present disclosure has the capability of real-time force sensing, data quantification and classification, and fast full inspection, and the device is easy to erect and install, so it can solve the problem of commercialization. The rotor vibration detection system has the problem that the measurement time is too long and cannot be fully detected in the production line of the product to be tested with high-speed rotating components such as fans.

As can be seen from the above-mentioned embodiments, another advantage of the present disclosure is that because the vibration force measuring device of the present disclosure can use a load cell sensor as the vibration amount sensor, it can directly measure the movement of the object to be measured. Force variation data with the advantages of low cost, easy access, and complete specifications.

As can be seen from the above-mentioned embodiments, another advantage of the present disclosure is that the measuring platform of the vibration force measuring device of the present disclosure can be supported by a frictionless or low-friction lifting device, so that external interference can be blocked, and the object to be measured can be effectively improved. The sensitivity of the measurement of the vibrational force of a thing.

As can be seen from the above-mentioned embodiments, another advantage of the present disclosure is that the connecting member of the vibration force measuring device of the present disclosure can adopt a flexible hinge, which can realize the isolation of the interference source outside a single plane, and thus can accurately measure the vibration force. Changes in the horizontal vibration force of the measured object.

Although the present disclosure has been disclosed above with examples, it is not intended to limit the present disclosure. Anyone with ordinary knowledge in this technical field can make various changes and modifications without departing from the spirit and scope of the present disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the appended patent application.

100a: Vibration force measuring device 100b: Vibration force measuring device 110: Measurement platform 112: Bearing surface 114: Fixtures 120: Lifting device 122: upper surface 124: Pedestal 126: Air flotation part 130: Sensor 140: Connector 150: Lifting device 152: Upper surface 154: Pedestal 156: Ball 158: Magnetic components X: coordinate axis Y: coordinate axis Z: coordinate axis

In order to make the above and other objects, features, advantages and embodiments of the present disclosure more clearly understood, the accompanying drawings are described as follows: [ FIG. 1 ] is a schematic perspective view of a vibration force measuring device according to an embodiment of the present disclosure; [ FIG. 2 ] is a schematic top view of a vibration force measurement device according to an embodiment of the present disclosure; [ FIG. 3 ] is a schematic side view of a vibration force measuring device according to an embodiment of the present disclosure; and [ FIG. 4 ] is a schematic side view of a vibration force measuring device according to another embodiment of the present disclosure.

Domestic storage information (please note in the order of storage institution, date and number) none Foreign deposit information (please note in the order of deposit country, institution, date and number) none

100a: Vibration force measuring device 110: Measurement platform 112: Bearing surface 114: Fixtures 120: Lifting device 122: upper surface 124: Pedestal 126: Air flotation part 130: Sensor 140: Connector X: coordinate axis Z: coordinate axis

Claims (9)

A vibration force measuring device, suitable for measuring an object to be measured with a high-speed rotating element, includes: a measuring platform with a bearing surface to carry the object to be measured; a lift device configured to lift the measurement platform off an upper surface of the lift device; a sensor configured to sense a vibration amount generated when the object to be tested is running; and A connecting piece connects the measuring platform and the sensor, and is configured to transmit the vibration of the object to be measured to the sensor, and the rigidity of the connecting piece is different in different directions. The vibration force measuring device according to claim 1, wherein the measuring platform comprises a fixture configured to fix the object to be measured on the measuring platform. The vibration force measuring device as claimed in claim 1, wherein the lifting device is an air bearing, and the air bearing can use gas to float the measuring platform away. The vibration force measuring device as claimed in claim 1, wherein the lifting device comprises at least three balls protruding from the upper surface of the lifting device, and the balls are configured to lift the measuring platform away from the upper surface of the lifting device surface. The vibration force measuring device according to claim 4, wherein the lifting device further comprises at least one magnetic attraction element, and the at least one magnetic attraction element is configured to exert a magnetic attraction force on the measuring platform. The vibration force measuring device according to claim 1, wherein the lifting device further comprises a base, the sensor is fixed on the base, and the lifting device, the sensor, and the connecting piece are composed of A natural frequency of a system is higher than a rotational frequency of the object to be tested. The vibration force measuring device according to claim 1, wherein the rigidity of the connecting member in a plane direction parallel to the bearing surface of the measuring platform is greater than the rigidity in a direction perpendicular to the plane. The vibration force measuring device according to claim 7, wherein the connecting member is a flexible hinge. The vibration force measuring device as claimed in claim 7, wherein the connecting member comprises a metal sheet.

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