CN220794516U - Detection device for installation quality of strain gauge - Google Patents

Abstract

The present utility model relates to a detection device for mounting quality of a strain gauge, the strain gauge being pre-mounted to a plurality of strain points in a device to be detected, comprising: a bracket; detect the body, include: a housing supported on the bracket; a detection thimble, at least a portion of which is accommodated in the housing such that it is axially movably held in the housing; and a force application part capable of applying a force in an axial direction to the detection thimble so that the detection thimble can be pushed against each respective predetermined position corresponding to each strain point in the device to be detected in the same direction to apply a pressure during the respective detection, the force application part being configured to apply a pressure in the same variation range to each respective predetermined position by monitoring a standard strain or a stress variation occurring in the detection thimble to obtain a corresponding variation of the strain gauge at the plurality of strain points. The detection device is simple in structure, small in space occupation and flexible in operation.

Description

Detection device for installation quality of strain gauge

Technical Field

The present utility model relates to a device for detecting the quality of attachment of a strain gauge.

Background

In the prior art, in particular in the field of wind power generation, gearboxes are widely used. In order to ensure the quality of the gearbox, the wind power generation gearbox must be subjected to a load distribution measurement experiment before being taken out of the farm, wherein the attachment of strain gauges at the tooth root of the gear ring of the gearbox becomes one of the key steps in the measurement experiment.

As is known in the art, tooth flank load distribution must be measured at each load step using a tooth root strain gauge according to the 2012 edition of standard IEC 61400-part 4 "design requirements for wind turbine gearboxes". The strain gauge is an element for detecting minute deformation, and can be stuck to the surface of the object to be detected. As an example, when the detected member is deformed, the strain gauge is also changed, so when the detected member to which the strain gauge is provided is subjected to tensile stress, the strain gauge is also correspondingly stretched, so that the resistance becomes large. In contrast, when the detected member is subjected to compressive stress, the strain gauge is also compressed accordingly, so that the resistance becomes small. The tooth flank load distribution measurement is based on this principle of strain gages. Therefore, the quality of the mounting quality (e.g., mounting position, mounting flatness, degree of fitting, etc.) of the strain gage determines the accuracy of the measurement result.

At present, most of the technical schemes adopted in the industry are to directly measure the resistance value of a full-bridge circuit arranged at the tooth root of a gear ring in a no-load state to judge whether the strain gauge is successfully installed. However, since the strain gauges are required to be attached to the tooth roots of the plurality of tooth rings of the same gear case, it is obvious that such a technical solution cannot determine whether or not the consistency of the mounting quality of the different strain gauges provided to the tooth roots of the plurality of tooth rings is good.

Although there may be devices that apply a load to the ring gear to verify the mounting quality of the strain gage, these verification devices tend to be complex in structure, bulky, and inflexible to operate.

Therefore, a flexible and easy-to-operate device is needed to detect the quality of the installation of the strain gage.

Disclosure of utility model

In order to solve at least some or all of the above technical problems, a technical solution of the present utility model is provided.

According to the present utility model, there is provided a detection device for mounting quality of a strain gauge, the strain gauge being mounted in advance at a plurality of strain points in a device to be detected, at which strain monitoring is required, the detection device comprising: a bracket; detect the body, detect the body and include: a housing supported on the bracket; a detection thimble including a front end portion, a middle portion, and a rear end portion, at least a portion of the detection thimble being configured to be received in the housing such that the detection thimble is axially movably retained in the housing, a force application member configured to apply a force to the detection thimble in an axial direction thereof such that the front end portion is capable of being urged in a respective same direction against respective predetermined positions in a device to be detected corresponding to respective strain points to apply a pressure during respective detection, wherein the force application member is configured to apply a pressure in a same variation range to the respective predetermined positions by monitoring a standard strain or a variation in the stress occurring to the detection thimble to obtain a corresponding variation of the strain gauge at the plurality of strain points.

Further, one or more plane parts uniformly distributed along the circumferential direction are arranged in the outer surface of the middle part of the detection thimble, which is positioned at the same axial distance; and one or more of the planar portions are respectively provided with at least one standard strain gauge; the gauge is configured to monitor a change in gauge strain of the thimble as the front end portion is urged against the corresponding predetermined position.

Further, the number of the planar portions is 4, one standard strain gauge is provided for each of the 4 planar portions, and the 4 standard strain gauges are commonly configured as a wheatstone full bridge circuit.

Further, the urging member is configured as a bolt extending through the housing in the axial direction in alignment with the rear end portion of the detection thimble.

Further, the bolt is provided with a scale corresponding to the standard strain variation of the detection thimble so that the standard strain variation can be approximated by the scale.

Further, the detection body further includes a rigid pad disposed between the front end portion of the bolt and the rear end portion of the detection thimble, the rigid pad being configured to move only axially in the housing and to be capable of pressing against the front end portion of the bolt and the rear end portion of the detection thimble, respectively, upon detection.

Further, the holder is configured to be removably secured to the device to be detected.

Further, the housing is configured to be removably secured to the bracket.

Further, the housing is configured to be rotatably fixed to the bracket such that the detection body is capable of orientation and positioning adjustment with respect to respective predetermined positions.

Further, the housing is configured to be composed of two or more components that are freely detachable such that the housing at least partially accommodates and supports the test ejector pins in its assembled state.

The detection device for the installation quality of the strain gauge has the advantages of simple structure, small space occupation and flexible operation, and allows the installation quality of the strain gauge, in particular consistency, in a limited space and in a flexible scene.

Drawings

Other salient features and advantages of the utility model will emerge from the following non-limiting description, provided for illustrative purposes, with reference to the following figures, in which:

fig. 1 shows a schematic side view of a detection device for the mounting quality of a strain gauge according to the utility model; and

Fig. 2 shows a schematic cross-sectional view of a detection device for the mounting quality of a strain gauge according to the utility model.

Detailed Description

First, the position and direction in the present utility model are defined as follows: the axial direction corresponds to the direction in which the body of the detection device for the mounting quality of the strain gauge (in particular of its detection spike) extends. The radial direction is perpendicular to the axial direction and the circumferential direction corresponds to the circumferential direction of the cross section of the detection thimble. In the present utility model, the geometry of the detection thimble is preferably cylindrical, i.e. the detection thimble has a circular cross-section perpendicular to the axial direction. Of course, similarly, for other cross-sectional configurations of the sensing needle, the orientation should be defined and understood as described above. Furthermore, as known to those skilled in the art, the vertical direction corresponds to a direction perpendicular to the ground surface.

Fig. 1 shows a schematic side view of a detection device 1 according to the utility model for the mounting quality of a strain gauge 3 and fig. 2 shows a schematic cross-sectional view of a detection device 1 according to the utility model for the mounting quality of a strain gauge 3. In fig. 1 and 2, the detection device 1 is in a detection state or a ready state for or ready for detecting the mounting quality of the strain gauge 3. Here, it is to be understood that the mounting quality of the strain gauge 3 includes, for example, but is not limited to, the mounting position, mounting flatness, fitting degree, orientation, and the like of the strain gauge itself, in other words, the mounting quality means fitting-related quality capable of affecting the accuracy degree of the strain gauge to measure the strain at the strain point of the device to be detected. Here, it is also to be understood that the strain point represents a position on the device 2 to be detected where stress monitoring is required. As will be appreciated by those skilled in the art, the strain gauge 3 is disposed at the relevant strain point of the device to be tested to monitor the corresponding strain change at the strain point. Further, in case the device to be detected is a ring gear of a wind power gearbox, the strain point may correspond to a position on the teeth of the ring gear near the tooth root on the tooth surfaces opposite each other between the teeth, i.e. near the lowest position between the teeth on the circumferential lateral surface of the teeth. By stress monitoring these strain points, the strain experienced by the teeth of the ring gear can be detected accordingly, and the quality of the ring gear can be detected.

Thus, as shown in fig. 1 and 2, the strain gauge 3 is pre-installed at a plurality of strain points in the device 2 to be inspected at which strain monitoring is required. The detection device 1 includes: a bracket 10; a detection body 20, the detection body 20 comprising: a housing 200 supported on the stand 10; a test spike 202 comprising a front end portion, a middle portion, and a rear end portion, at least a portion of the test spike being configured to be received in the housing 200 such that the test spike 202 is axially movably retained in the housing 200; and a force application member 204 configured to apply a force in the axial direction to the detection thimble 202 such that the front end portions can be pushed against respective predetermined positions in the device 2 to be detected corresponding to respective strain points in the same orientation to apply a pressure during respective detection, wherein the force application member 204 is configured to apply a pressure in the same variation range to respective predetermined positions by monitoring a standard strain or a stress variation occurring to the detection thimble 204 to obtain corresponding variations of the strain gauge 3 at the plurality of strain points.

First, in the present application, "respective predetermined positions corresponding to respective strain points" means relative spatial positions equivalent with respect to each individual strain point, thereby ensuring that the same stress is applied to each of these respective predetermined positions, respectively, to generate the same stress influence to each of the respective plurality of strain points.

Further, the principle that the detection device 1 of the present application can detect the mounting quality of the strain gauge 2 is briefly described herein as: since the detection device 1 is configured to be able to exert a pressure in the same orientation and in the same variation range with respect to respective predetermined positions of a plurality of strain points to respectively generate stress influences in a uniform range on the plurality of strain points, it is thereby possible to detect the mounting quality of the strain gages 3 by detecting whether the strain measurement results (i.e., strain changes) generated and measured by the strain gages 3 at the plurality of strain points are also in a uniform range, for example, when some of the strain measurement results are not in the uniform range, it is possible to determine that there is a problem in the mounting quality of the strain gages 3 corresponding to the strain measurement results.

Further, in an embodiment of the present application, optionally, in order to ensure flexibility of the detection device 1, the housing 200 of the detection device 1 is configured to be removably fixed to the stand 10, as shown in fig. 1 and 2. The housing is configured to be removably secured to the bracket 10 by means of screws 206. In this case, this facilitates the disassembly and assembly of the detection device 1. Of course, this is merely exemplary, and the housing 200, or at least a portion of the housing 200, is certainly contemplated as being non-removably secured to the stand 10 without departing from the scope of the present application. Furthermore, it should be understood that while the structure for housing the test thimble 202 is described herein as the housing 200, it will be understood by those skilled in the art that this is not limiting and that it is contemplated that the housing 200 could be replaced with a non-sealed frame that would still achieve the technical effects described herein while reducing the overall weight of the test device 1.

Further, in an embodiment of the present application, housing 200 is optionally configured from two or more components that are freely removable such that the housing at least partially houses and supports the test spike in its assembled state. As shown in fig. 1 and 2, the housing is constructed of two freely detachable components, namely, an upper housing 200-1 and a lower housing 200-2. Further, the upper housing 200-1 is configured to be secured to a bracket, and the lower housing 200-2 is capable of mating with the upper housing 200-1 (e.g., without limitation, via a screw fit 208, a snap fit, etc.). As shown in fig. 1 and 2, the lower housing 200-2 includes a through hole provided in a lower end surface to enable the test thimble 202 to extend out of the lower housing. As shown in fig. 1 and 2, the upper housing 200-1 includes a through hole provided in an upper end surface so that the force application member 204 can extend into the upper housing 200-1 so as to be able to apply a force to the detection needle 202. This configuration also facilitates the disassembly of the detection device 1, thereby facilitating the flexible use of the detection device 1.

Further, in the embodiment of the present application, alternatively, as shown in fig. 1 and 2, the urging member 204 is configured as a bolt extending through the housing 200 in the axial direction in alignment with the rear end portion of the detection thimble 202, but the present application is not limited thereto. One skilled in the art can contemplate any configuration capable of applying a force in an axial direction to sensing needle 202 without departing from the scope of the present application. As a possible example, the example component is configured as a cam mechanism or an elastic mechanism or the like having a position holding device.

Further, in the embodiment of the present application, optionally, in order to ensure that the standard stress in a predetermined range is applied to the detection needle 202 by the force application member 204, one or more flat portions 210 uniformly distributed in the axial direction are provided in the outer surface at the same axial distance in the middle portion of the detection needle 202; and one or more of the planar surfaces 210 are each provided with at least one standard strain gauge 212; these gauge tabs 212 are configured to monitor the gauge change or stress of the test thimble 202 as the front end portion is pushed against a corresponding predetermined position, as shown in FIG. 2. In practice, the planar portion 210 is provided because the standard strain gage 212 generally requires a planar arrangement and cannot flex, and therefore, the location of the standard strain gage 212 generally requires a planar arrangement. This approach provides for real-time monitoring of the stress experienced by the test spike 202, such that by monitoring of these at least one standard strain gauge, it is ensured that the test spike 202 is subjected to standard strain or stress variations in a predetermined range, thereby ensuring that pressure in the same range of variation is applied by the test spike 202 to the respective predetermined location.

It is to be understood herein that the predetermined range represents an acceptable range of forces that are desired to be applied to the respective predetermined locations. In practice, it is more desirable to apply forces of exactly the same magnitude to each respective predetermined location, however, detecting spike 202 does not actually ensure that a perfectly consistent and unbiased pressure is applied to each respective predetermined location, taking into account factors such as the accuracy of adjustment of force applying member 204 or the accuracy of measurement of standard strain gauge 212. For this reason, it is necessary to consider that the force applied by the detection needle 202 is in a range of the magnitude of the desired applied force, that is, a force that floats up and down by a certain magnitude from the magnitude of the desired applied force, thereby improving the detection efficiency and reducing the complexity of use of the detection device. Further, as will be appreciated by those of ordinary skill in the art, a smaller interval of this predetermined range indicates that the more uniform the standard stress or strain change experienced by test spike 202, the more uniform the pressure applied by test spike 202 to the corresponding predetermined location. For example, the predetermined range represents a range of plus/minus one percent of the magnitude of the desired applied force, e.g., if the magnitude of the desired applied force is 100N, the predetermined range is at [99, 101]. The above numerical intervals of the predetermined range and the magnitudes are not limiting but merely examples, and in practice the magnitude of the desired applied force may be any selected value and the magnitude of the floating of the predetermined range with respect to the magnitude may be arbitrarily adjusted, for example 0.1%, 0.5%, 2%, even 5%, as required by the detection accuracy.

Based on this, since the sensing needle 202 is subjected to standard stress or strain changes in a predetermined range, the sensing needle 202 also naturally exerts a substantially uniform pressure on the respective predetermined locations (i.e., pressures in the same range of variation, which is positively correlated with the predetermined range), and thus the stress effects of these locations on their corresponding strain points are also substantially uniform, which is fed back to the strain gauge 3 arranged to sense strain changes at these corresponding strain points, resulting in substantially the same strain measurements (i.e., measurements or strain changes in substantially the same range). Alternatively, the strain change caused by the test thimble 202 experiencing a satisfactory quality of mounting the strain gauge 3 at the corresponding strain point at the magnitude of the desired applied force may be known in advance, which may be known through prior experimentation. By means of this test, it is also possible to know the range of strain variation caused by the detection thimble 202 subjected to standard stress or strain variation in a predetermined range for the strain gauge 3 mounted with satisfactory quality at the corresponding strain point, thereby facilitating the detection of the mounting quality of the strain gauge 3. Of course, this is merely exemplary, and a person skilled in the art can easily find a strain gauge with abnormal data by simply measuring the respective strain of the strain gauge 3 and comparing whether these strain measurements are identical on the basis of completely unaware of the above-described test results.

Further, in the embodiment of the present application, the number of the planar portions 210 is 4, and the 4 planar portions 210 are provided with one standard strain gauge 212, respectively, and the 4 standard strain gauges are commonly configured as a wheatstone full bridge circuit. By means of the wheatstone full bridge circuit, it is possible to ensure the accuracy of the stress or strain detection of the detection thimble 202, and thus to ensure that the detection thimble 202 is as much as possible subjected to a more accurate standard stress or strain in a predetermined range, thereby exerting a more uniform pressure on the respective predetermined positions.

Further, the urging member 204, particularly an urging member configured as a bolt, is provided with a scale (not shown, in the case of a bolt, the scale may be provided on a cylinder of the bolt in the axial direction of the bolt) corresponding to the standard strain characteristics of the detection thimble 202 so that standard stress variation can be quickly approximated in accordance with the scale. It should be appreciated herein that there may be significant errors in the standard strain characteristics of the sensing needle 202 (i.e., the amount of stress or strain to which the sensing needle 202 is subjected when the force applying member 204 is in the scale), as represented by the scale, the scale may be used to pre-adjust the standard stress or strain changes of the sensing needle to enable quick access to the standard stress changes when sensing each of the plurality of strain gauges 3, saving adjustment time. Of course, the scale may have a sufficiently high accuracy such that the position of the force applying member corresponding to the scale corresponds to the standard stress variation with high accuracy.

Further, in the embodiment of the present application, as shown in fig. 2, the detection body 20 further includes a rigid pad 214 provided between the force application end of the force application member 204 (the front end of the bolt in the case of the bolt) and the rear end of the detection thimble 202, the rigid pad 214 being configured to move only axially in the housing 200 and to be capable of being pressed against the force application end of the force application member 204 and the rear end of the detection thimble 202, respectively, in the detection state of the detection device 1. By means of the rigid spacer 214, the application range of the application member 204 is significantly extended, and the application member 204 and the detection thimble 202 of different sizes can be adapted, which facilitates maintenance and cross use of the detection device, which significantly extends the application range of the detection device 1.

Further, in the embodiment of the present application, the device to be detected 2 is fixed with respect to the detection device 1 at the time of detection to ensure that the force applied thereto is stable. Further, for different strain points of the device to be detected 2, in order to ensure that a consistent influence can be exerted on the strain points when the detection is performed, it is necessary to ensure that the same oriented pressure can be exerted on the device to be detected 2 with respect to respective predetermined positions of its plurality of strain points.

To this end, as shown in fig. 1 and 2, it is conceivable that the detection device 1 is configured to be movable relative to the device to be detected 2 to ensure that the detection device 1 is able to adjust the orientation relative to the device to be detected 2 so that the same directional pressure can be applied to respective predetermined positions with respect to a plurality of different strain points on the device to be detected 2. To this end, alternatively, it is conceivable that the bracket 10 is configured to be removably fixed to the device to be detected 2 so that, at the time of the installation quality detection of the strain gauge 3 for each of the plurality of strain points, the detection device 1 can be integrally positioned to different positions on the device to be detected 2, respectively, which represent positions disposed at equal intervals along the outer peripheral surface of the ring gear in the case where the device to be detected 2 is the ring gear. In this case, it is conceivable to provide corresponding fixing portions 216 on the device 2 to be detected to cooperate with the holder 10. As an example, both the device to be inspected 2 and the bracket 10 are provided with threaded holes so that the bracket 10 can be fixed to the device to be inspected 2 by means of screws when the inspection is performed. Of course, this is merely exemplary, and the removable securement between the device 2 to be tested and the stand 10 may also include, but is not limited to, snap-fit securement, adhesive securement, magnetic securement, etc., without departing from the scope of the present application. Note that these different positions for the fixing bracket 10 in the device 2 to be detected are configured to ensure that the detection device 1 applies the same directional force to each of these respective predetermined positions.

Furthermore, such a solution of removably fixing the holder 10 to the device 2 to be tested as described above also allows saving the space occupied by the detection device and enabling its flexible setting without being limited to the use environment.

Furthermore, optionally, in order to further flexibly adjust the position of the detection device 1 to which the pressure is applied to the device 2 to be detected and adjust the orientation of the applied pressure, it is also conceivable that the housing 200 of the detection body 20 of the detection device 1 is configured to be rotatably fixed to the stand 10 such that the detection body 20 can be oriented and positionally adjusted with respect to the respective predetermined positions.

The above-described embodiments of the present application are intended to be illustrative only and not limiting. It will be understood by those skilled in the art that various modifications can be made to the above-described embodiments in light of the present disclosure without departing from the scope of the present disclosure, and such modifications or equivalents are intended to fall within the scope of the present disclosure.

Claims (10)

1. A detection device (1) for the quality of the installation of strain gages (3) pre-installed at a plurality of strain points in a device (2) to be detected, where stress monitoring is required, characterized in that the detection device (1) comprises:

A bracket (10);

-a detection body (20), the detection body (20) comprising:

A housing (200) supported on the bracket (10);

A detection spike (202) comprising a front end portion, a middle portion, and a rear end portion, at least a portion of the detection spike (202) being configured to be received in the housing (200) such that the detection spike (202) is axially movably retained in the housing (200);

A force application member (204) configured to apply a force in an axial direction thereof to the detection needle (202) so that the front end portions can be pushed against respective predetermined positions in the device (2) to be detected, respectively, in the same orientation during respective detection to apply pressure,

Wherein the force application member (204) is configured to apply a pressure in the same variation range to the respective predetermined positions by monitoring a standard strain or a stress variation occurring in the detection thimble (202) to obtain a corresponding variation of the strain gauge (3) at the plurality of strain points.

2. The detection device (1) according to claim 1, characterized in that one or more flat portions (212) distributed uniformly in the axial direction are provided in the outer surface at the same axial distance in the intermediate portion of the detection spike (202); and said one or more planar portions (212) are each provided with at least one standard strain gauge; the gauge is configured to monitor a change in gauge strain of the sensing thimble as the front end portion is urged against the respective predetermined position.

3. The detection device (1) according to claim 2, characterized in that the number of planar portions (212) is 4, the 4 planar portions (212) are each provided with one standard strain gauge, and the 4 standard strain gauges are commonly configured as a wheatstone full bridge circuit.

4. A detection device (1) according to any one of claims 1 to 3, wherein the force application member (204) is configured as a bolt extending through the housing (200) in axial direction in alignment with the rear end of the detection spike (202).

5. The detection device (1) according to claim 4, characterized in that the bolt is provided with a scale corresponding to the standard strain variation of the detection thimble (202) such that the standard strain variation is accessible according to the scale.

6. The detection device (1) according to claim 4, wherein the detection body (20) further comprises a rigid pad (214) arranged between the front end of the bolt and the rear end of the detection spike (202), the rigid pad (214) being configured to move only axially in the housing (200) and to be able to press against the front end of the bolt and the rear end of the detection spike (202), respectively, when detection is performed.

7. A detection device (1) according to any one of claims 1 to 3, characterized in that the holder (10) is configured to be removably fixable to the device (2) to be detected.

8. A detection device (1) according to any one of claims 1 to 3, characterized in that the housing (200) is configured to be removably fixed to the holder (10).

9. A detection device according to any one of claims 1 to 3, characterized in that the housing (200) is configured to be rotatably fixed to the bracket (10) such that the detection body (20) is capable of orientation and positioning adjustment with respect to the respective predetermined position.

10. A testing device (1) according to any one of claims 1 to 3, characterized in that the housing (200) is configured to be composed of two or more parts that are freely detachable such that the housing (200) at least partially accommodates and supports the testing spike (202) in its assembled state.