CN107504922A - A kind of coaxality measuring mechanism of circular aperture - Google Patents

Abstract

The invention discloses a circular aperture coaxiality measuring device, which comprises a disk body and a laser tracker; the radial direction of the disk body is provided with a telescopic device capable of extending and contracting along the radial direction of the disk body and equal in length. arm, the number of the telescopic arms is at least 2 and is evenly arranged along the circumference of the disc body, and the center of the disc body is provided with a reflective target; the telescopic arm includes The screw rod and the wire sleeve arranged in the radial direction of the body, one end of the screw rod is threadedly matched with the wire sleeve, and the other end of the screw rod is fixed with a first bevel gear; the circumferential direction of the disc body is evenly arranged There is a telescopic opening, and the wire sleeve and the telescopic opening are slidably matched along the radial direction of the disc body; an adjustment mechanism is also provided on the disc body, and the adjustment mechanism includes a A second bevel gear meshed with both gears and a drive assembly for driving the second bevel gear. The above-mentioned device realizes the coaxiality measurement of the circular aperture.

Description

A Coaxiality Measuring Device of Circular Aperture

technical field

The invention relates to the technical field of dimensional tolerance measurement, in particular to a circular aperture coaxiality measuring device.

Background technique

The coaxiality measurement of long hollow round rods is one of the most basic measurement items in the field of tolerance measurement of machined parts, and it is widely used in the fields of precision instruments and even military manufacturing and testing, installation and positioning. The cylindricity tolerance is used to control the degree of misalignment between the measured axis and the reference axis, which should be theoretically coaxial. The cylindricity tolerance zone is a cylindrical surface area whose diameter is a certain tolerance value and is coaxial with the datum axis. The detection of coaxiality is to find out the maximum distance between the measured axis and the reference axis, and take its double value as the coaxiality error.

At present, the indicator method is mainly used to measure the coaxiality of circular rods. As shown in Figure 1, the measured part is installed between the two coaxial tops 1 of the precision indexing device, and the common axes of the two tops 1 are parallel. On the bottom surface 2 of the plate, the common axis is used as the measurement datum. In the axial measurement, take the absolute value of the reading difference measured by the indicator on the normal section perpendicular to the reference axis as the coaxiality error on the section. Rotate the measured part, measure several sections according to the above method, and take the maximum value (absolute value) of the readings of each section as the coaxiality error of the part.

However, the above method can only be used to measure the coaxiality of the outer cylindrical surface of a circular rod, and it is not suitable for the coaxiality of the circular aperture on the workpiece. There is no comparison for the coaxiality of the circular aperture. Good measuring device to measure.

To sum up, how to solve the problem of coaxiality measurement of circular apertures has become a technical problem to be solved urgently by those skilled in the art.

Contents of the invention

The object of the present invention is to provide a coaxiality measuring device of a circular aperture, so as to realize the coaxiality measurement of the circular aperture.

In order to achieve the above object, the present invention provides a circular aperture coaxiality measuring device, including a disc body and a laser tracker;

The radial direction of the disc body is provided with a telescopic arm that can expand and contract along the radial direction of the disc body, the number of the telescopic arms is at least 2 and is evenly arranged along the circumferential direction of the disc body, And the central position of the disc body is provided with a reflective target;

The telescopic arm includes a screw rod and a wire sleeve arranged radially along the disc body, one end of the screw rod is threadedly engaged with the wire sleeve, and the other end of the screw rod is fixed with a first bevel gear; The circumference of the disc body is evenly arranged with telescopic openings, and the wire sleeve is slidably matched with the telescopic openings along the radial direction of the disc body;

An adjustment mechanism is also provided on the disc body, and the adjustment mechanism includes a second bevel gear meshing with each of the first bevel gears and a drive assembly for driving the second bevel gears;

The laser tracker is used to emit laser light to the reflective target, and the emitting direction forms a preset angle with the central axis of the disc body, and the laser tracker can also receive the laser light reflected by the reflective target. Returning the laser light, and obtaining the three-dimensional coordinates of the circle center of the corresponding position in the circular aperture to be measured according to the returned laser light.

Preferably, the drive assembly includes a fixed shaft and a hand wheel, and one end of the fixed shaft located inside the disc body is fixedly connected to the shaft center of the second bevel gear, and the fixed shaft is located on the disc body. One end outside the disc body is fixedly connected with the hand wheel.

Preferably, the number of the telescopic arms is two, and the screw rods of the two telescopic arms are an integral structure with coaxial core lines.

Preferably, the number of the disc bodies is 2, and the 2 disc bodies are arranged concentrically.

Preferably, the two first bevel gears (12) are connected through a transmission mechanism.

Preferably, the end of the wire sheath is further provided with a running mechanism for adhering to the inner wall of the circular aperture to be tested.

Preferably, the running mechanism includes a roller with a rolling surface for fitting with the inner wall of the circular aperture to be measured, and at least two rollers are arranged at the end of each of the wire sleeves, and the rollers are arranged in parallel, And the roller shaft of the roller is perpendicular to the central line of the disc body.

Preferably, the traveling mechanism further includes a traveling crawler, and the traveling crawler is sheathed on the rolling surfaces of the two outermost rollers.

Preferably, the traveling mechanism further includes a motor for driving the rollers, and a reduction gear set is arranged between the motor and the rollers.

Preferably, a guide rail is provided on the telescoping opening, and a concave groove that slides and fits with the guide rail is provided on the wire sleeve.

Compared with the introduction of the background technology, in the actual use of the above-mentioned coaxiality measuring device for circular apertures, by placing the disc body inside the circular aperture to be measured, the second bevel gear is driven by the drive assembly, and the second The second bevel gear drives the first bevel gear corresponding to each telescopic arm to rotate, and then the screw rod arranged radially along the disc body rotates. The wire sleeve is restricted by the telescopic opening and will not rotate, and then slides along the telescopic opening. In this way, the telescopic arm is extended along the radial direction of the disc body at an equal length, so that the end of the wire sleeve fits the inner wall of the circular aperture to be measured, and the center of the disc body is provided with a reflective target, so through the laser When the tracker emits laser light to the reflective target, of course the emission direction is at a preset angle with the central axis of the disc body. The reflection of the reflective target will form a return laser. After the laser tracker receives the return laser, it processes it to obtain The three-dimensional coordinates of the center of the corresponding position, after moving the position of the disc body, the three-dimensional coordinates of the center of the circle of more positions can be obtained through the laser tracker, and finally the data is processed and analyzed according to the three-dimensional coordinates of the center of the circle at multiple different positions, and it can be obtained The coaxiality of the circular aperture to be measured, thus realizing the coaxiality measurement of the circular aperture.

Description of drawings

Fig. 1 is the structural representation of the measuring device of the coaxiality of traditional circular bar;

FIG. 2 is a schematic diagram of the overall structure of a circular aperture coaxiality measuring device provided by an embodiment of the present invention;

Fig. 3 is a schematic diagram of the internal structure of the disc body provided by the embodiment of the present invention;

Fig. 4 is a schematic structural diagram of the telescopic arm provided by the embodiment of the present invention;

Fig. 5 is a schematic structural diagram of a laser tracker provided by an embodiment of the present invention.

In Figure 1-5 above,

Top 1, Flat Bottom 2, Disc Body 3, Telescopic Arm 4, Reflective Target 5, Laser Tracker 6, Screw Mandrel 7, Thread Sleeve 8, First Bevel Gear 9, Telescopic Port 10, Second Bevel Gear 11, Drive assembly 12, transmission mechanism 13, traveling mechanism 14, roller 15, motor 16, reduction gear set 17, concave groove 18, power supply 19.

detailed description

The core of the present invention is to provide a circular aperture coaxiality measurement device to realize the circular aperture coaxiality measurement.

In order to enable those skilled in the art to better understand the technical solutions provided by the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

As shown in Fig. 2-Fig. 5, a kind of coaxiality measuring device of circular aperture provided by the embodiment of the present invention comprises disc body 3 and laser tracker 6; The telescopic arm 4 of the radially equal length of the disc body 3 is at least two and is evenly arranged along the circumferential direction of the disc body 1, and the center of the disc body 3 is provided with a reflective target 5; The telescopic arm 4 comprises a screw mandrel 7 and a wire sleeve 8 arranged radially along the disc body 4, one end of the screw mandrel 7 is screwed with the wire sleeve 8, and the other end of the screw mandrel 7 is fixed with a first bevel gear 9; The circumference of the body 3 is evenly arranged with telescopic openings 10, and the wire sleeve 8 and the telescopic openings 10 are slidably matched along the radial direction of the disc body 3; The second bevel gear 11 that the gears 9 are all meshed with and the driving assembly 12 for driving the second bevel gear 11; the laser tracker 6 is used to emit laser light to the reflective target 5, and the emission direction is consistent with the central axis of the disc body 3 With a preset included angle, the laser tracker 6 can also receive the return laser light reflected by the reflective target 5, and obtain the three-dimensional coordinates of the center of the circle corresponding to the position in the circular aperture to be measured according to the return laser light.

In the actual use of the above-mentioned coaxiality measuring device for a circular aperture, the disc body is placed inside the circular aperture to be measured, and the second bevel gear is driven by the drive assembly, and the second bevel gear drives each telescopic arm The corresponding first bevel gear rotates, and then the screw rod arranged radially along the disk body rotates. The wire sleeve is restricted by the telescopic opening and will not rotate, and then slides along the telescopic opening, thus realizing the expansion of the telescopic arm along the disk. The radial and equal length of the body is elongated, so that the end of the wire sleeve fits the inner wall of the circular aperture to be measured, and a reflective target is set in the center of the disc body, so the laser is emitted to the reflective target through the laser tracker When, of course, the emission direction and the central axis of the disk form a preset angle, the reflection of the reflective target will form a return laser. After the laser tracker receives the return laser, it will process it to obtain the three-dimensional coordinates of the center of the corresponding position. After moving the position of the disc body, the three-dimensional coordinates of the center of the circle of more positions can be obtained through the laser tracker, and finally the data processing and analysis can be carried out according to the three-dimensional coordinates of the circle center of multiple different positions, and the coaxiality of the circular aperture to be measured can be obtained. degree, thus realizing the coaxiality measurement of the circular aperture.

What needs to be explained here is that those skilled in the art should be able to understand that, in order to realize the expansion and contraction along the radial direction of the disc body 3, the screw rod should only have the screw rod around itself with the disc body. The degree of freedom of rotation in the axial direction, and when the screw rod rotates, the wire sleeve can only move radially along the disc body due to the limiting effect of the telescopic opening, so as to realize the telescopic movement of the wire sleeve, that is, the telescopic movement of the telescopic arm. The specific implementation method can be that the screw rod is fixed on the disc body through bearings to realize that the screw rod only has the degree of freedom to rotate around its own axis relative to the disc body, or it can be realized in other structural forms commonly used by those skilled in the art.

In addition, it should be noted that the data processing and analysis of the coordinates of the center of the circle at multiple different positions can be embedded in the corresponding software program in the laser tracker, so as to complete the corresponding data processing and obtain the coaxiality of the circular aperture, or it can be It is to put the three-dimensional coordinates of the circle center obtained by the laser tracker into the corresponding data processing equipment for data processing, such as a computer with corresponding data processing and analysis software installed. In addition, it should be noted that the workpiece corresponding to the above-mentioned circular aperture to be measured may be a circular aperture provided at the axial center of a round rod, or a circular aperture provided on a rectangular rod. As long as it is a workpiece with a circular aperture, it can be measured. Of course, the circular aperture mentioned here generally refers to a workpiece with a large aperture, because the disc body needs to be placed inside the circular aperture. The large aperture mentioned here The size standard is that the aperture that can be put into the disc body can be called a large aperture.

In some specific embodiments, the above-mentioned drive assembly 12 includes a fixed shaft and a hand wheel, and one end of the fixed shaft located inside the disc body 3 is fixedly connected with the axis of the second bevel gear 11, and the fixed shaft is located at the disc body 3 One end of the outside is fixedly connected with the handwheel. Turning the hand wheel causes the second bevel gear to rotate, and then drives each first bevel gear meshed with the second bevel gear to rotate, and then the thread sleeve on the screw rod undergoes telescopic movement. Of course, it can be understood that the above-mentioned handwheel drive is only an example of the drive assembly in the embodiment of the present invention, and it can also be other drive assemblies commonly used by those skilled in the art, such as motor drive and the like.

In some more specific embodiments, the number of the above-mentioned telescopic arms 4 is preferably two, and the screw rods 7 of the two telescopic arms 4 are an integral structure with coaxial core lines. By setting the screw rods 7 of the two telescopic arms 4 into an integrated structure with coaxial centerlines, the second bevel gear only needs to be meshed with the first bevel gear on the screw rod to realize simultaneous equalization of the two telescopic arms. The stretchable length not only saves the quantity of the first bevel gear, but also facilitates the installation of the second bevel gear. Of course, it can be understood that the number of the above-mentioned telescopic arms is 2 is only a preferred example of the embodiment of the present invention, and it can also be more than 2, such as 3, 4, 5, 6, 7, 8 or more.

In a further embodiment, the number of the above-mentioned disc bodies 3 is preferably two, and the two disc bodies 3 are arranged concentrically. By arranging two disks concentrically, the coaxiality measurement device of the circular aperture is more stable and reliable when placed in the circular aperture to be measured, and by At the same time, the laser tracker is arranged so that the coaxiality measuring device with a circular aperture can measure the three-dimensional coordinates of the two circle centers when the circular aperture coaxiality measuring device is in one position, making the measurement more efficient.

In some more specific embodiments, the two first bevel gears 9 can be connected through a transmission mechanism 13 . By arranging a transmission mechanism between the two first bevel gears 9, when one first bevel gear is adjusted, the other first bevel gear will also rotate synchronously, so that only one drive mechanism can be arranged to realize the adjustment The telescopic arms of the two disc bodies are adjusted simultaneously.

In a further embodiment, the end of the above-mentioned wire sheath 8 may also be provided with a running mechanism 14 for adhering to the inner wall of the circular aperture to be tested. By arranging the traveling mechanism 14, the movement of the coaxiality measuring device of the circular aperture in the circular aperture to be measured is more convenient.

In some more specific embodiments, the specific structure of the above-mentioned walking mechanism 14 can be a roller 15 that includes a rolling surface for fitting with the inner wall of the circular aperture to be measured, and the end of each wire sleeve 8 is at least provided with 2 Two rollers 15 arranged in parallel, and the rollers of the rollers 15 are perpendicular to the center line of the disc body 3. Of course, it can be understood that the above-mentioned rollers are only a preferred example of the walking mechanism in the embodiment of the present invention, and may also be other walking mechanisms commonly used by those skilled in the art, such as the structure of a ski with a smooth surface.

In some more specific embodiments, the above-mentioned traveling mechanism 14 may also include a walking crawler, which is sheathed on the rolling surfaces of the two outermost rollers 15 . By setting the walking track for transmission, the end of the wire sleeve of the telescopic arm and the inner wall of the circular aperture to be measured are more smoothly attached, avoiding scratches caused by hard and hard contact to the circular aperture to be measured.

In a further embodiment, the traveling mechanism 14 can also include a motor 16 for driving the rollers 15. By setting the motor, the coaxiality measuring device of the circular aperture can automatically walk in the circular aperture to be measured. Everyone should be able to understand that the motor should be connected to a corresponding power supply 19 in order to realize the driving function, and in order to make the motor control more convenient, the motor can also be controlled by a remote controller. In addition, a reduction gear set 17 is arranged between the motor 16 and the roller 15, and the speed directly output by the motor is reduced through the reduction gear set, so that the control of the traveling distance of the traveling mechanism is more convenient and easy to control. It should be noted here that the above-mentioned traveling mechanism may be driven by the above-mentioned motor, or may be manually driven, but the embodiment of the present invention preferably adopts the motor-driven method.

In some other specific embodiments, the specific structure that the wire sleeve 8 and the telescopic opening 10 realize sliding fit along the radial direction of the disc body may be that the telescopic opening 10 is provided with a guide rail, and the wire sleeve 8 is provided with a sliding fit with the guide rail. The concave groove 18. Of course, it can be understood that the above is only an example of the embodiment of the present invention for realizing the radial sliding fit of the wire sleeve and the telescopic opening along the disc body, and other sliding fit structures commonly used by those skilled in the art can also be used.

The above is a detailed introduction to the coaxiality measuring device for circular apertures provided by the present invention. It should be noted that each embodiment in this specification is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. For the same and similar parts in each embodiment, refer to each other, that is, Can.

It should also be noted that in this article, relational terms such as first and second etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that these entities or operations Any such actual relationship or order exists between. Moreover, the term "comprises", "comprises" or any other variation thereof is intended to cover a non-exclusive inclusion such that an article or device comprising a set of elements includes not only those elements but also other elements not expressly listed, Or also include elements inherent in the article or device. Without further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in an article or device comprising the aforementioned element.

In this paper, specific examples are used to illustrate the principle and implementation of the present invention, and the descriptions of the above embodiments are only used to help understand the method and core idea of the present invention. It should be pointed out that for those skilled in the art, without departing from the principle of the present invention, some improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims (10)

1. A coaxiality measuring device of a circular aperture is characterized in that, comprising a disc body (3) and a laser tracker (6); The radial direction of the disc body (3) is provided with telescopic arms (4) that can expand and contract along the radial direction of the disc body (3), the number of the telescopic arms (4) is at least 2 and uniformly arranged along the circumference of the disc body (1), and a reflective target (5) is provided at the center of the disc body (3); The telescopic arm (4) includes a screw rod (7) and a wire sleeve (8) arranged radially along the disc body (4), and one end of the screw rod (7) is connected to the wire sleeve (8). ) thread fit, the other end of the screw mandrel (7) is fixed with a first bevel gear (9); the circumference of the disc body (3) is evenly arranged with telescopic openings (10), and the wire sleeve (8 ) slidingly cooperates with the telescopic opening (10) along the radial direction of the disc body (3); An adjustment mechanism is also arranged on the disc body (3), and the adjustment mechanism includes a second bevel gear (11) meshed with each of the first bevel gears (9) and a second bevel gear (11) for driving the second bevel gear (9). The drive assembly (12) of the bevel gear (11); The laser tracker (6) is used to emit laser light to the reflective target (5), and the emission direction is at a preset angle with the central axis of the disc body (3), and the laser tracker ( 6) It is also possible to receive the return laser light reflected by the reflective target (5), and obtain the three-dimensional coordinates of the circle center of the corresponding position in the circular aperture to be measured according to the return laser light. 2. the coaxiality measuring device of circular aperture as claimed in claim 1, is characterized in that, described driving assembly (12) comprises fixed shaft and hand wheel, and described fixed shaft is positioned at described disc body (3 ) inside one end is fixedly connected with the axis position of the second bevel gear (11), and one end of the fixed shaft outside the disc body (3) is fixedly connected with the hand wheel. 3. the coaxiality measuring device of circular aperture as claimed in claim 1, is characterized in that, the quantity of described telescopic arm (4) is 2, and the screw mandrel (4) of 2 described telescopic arms (4) 7) It is an integral structure with coaxial core lines. 4. the coaxiality measuring device of circular aperture as claimed in claim 1, is characterized in that, the quantity of described disc body (3) is 2, and 2 described disc bodies (3) are the same Axis arrangement. 5. The coaxiality measuring device for a circular aperture according to claim 4, characterized in that, the two first bevel gears (9) are connected through a transmission mechanism (13). 6. the coaxiality measuring device of circular aperture as claimed in claim 1, is characterized in that, the end of described silk sleeve (8) is also provided with the walking that is used to fit with the inner wall of described circular aperture to be detected. Agency (14). 7. the coaxiality measuring device of circular aperture as claimed in claim 6, is characterized in that, described traveling mechanism (14) comprises the roller that rolling surface is used for being fitted with the inner wall of described circular aperture to be measured (15), the end of each said wire sleeve (8) is provided with at least 2 described rollers (15) that the rollers are arranged in parallel, and the rollers of the rollers (15) are perpendicular to the disc body ( 3) Centerline. 8. The coaxiality measuring device of circular aperture as claimed in claim 7, is characterized in that, described running gear (14) also comprises walking crawler belt, and described walking crawler belt is sleeved on the two described outermost ones that are positioned at outermost. on the rolling surface of the roller (15). 9. the coaxiality measuring device of circular aperture as claimed in claim 6, is characterized in that, described running gear (14) also comprises the motor (16) that is used to drive described roller (15), and described A reduction gear set (17) is also arranged between the motor (16) and the roller (15). 10. The coaxiality measuring device of circular aperture as claimed in claim 1, is characterized in that, guide rail is provided on the described telescopic opening (10), and described wire sleeve (8) is provided with and slides with described guide rail. Fitting concave groove (18).