A laser tracker automatic contact measurement target ball device

Abstract

The invention discloses a device for automatically contacting and measuring a target ball of a laser tracker, comprising a target ball, an extension rod unit, an intermediate connecting seat, a bottom guide base and a data processing unit, wherein the target ball is mounted on the extension rod unit, the extension rod unit is connected to the intermediate connecting seat, the intermediate connecting seat is connected to the bottom guide base, and the data processing unit is mounted on both sides of the bottom guide base; the target ball is connected to a guide rod extending from the extension rod unit by a thread, a compression spring is inserted into the lower end of the guide rod, one end of a connecting rod of a first displacement sensor is matched with the tail of the guide rod by a thread, and the displacement generated when the target ball is in axial contact with the measured target is measured; in the bottom guide base, the bottom of the ball head seat is in contact with the top plane of the spring mounting seat, and a second displacement sensor is installed in the inner hole of the spring mounting seat, and the displacement generated when the target ball is in radial contact with the measured target is measured. The invention can realize automatic contact measurement of a laser tracker without manual operation, thereby improving work efficiency.

Description

Technical Field

[0001] The invention belongs to the technical field of measuring equipment, and in particular relates to a device for automatically contacting and measuring a target ball with a laser tracker. Background Art

[0002] Laser tracker is a high-precision large-size measuring instrument in industrial measurement systems. It integrates various advanced technologies such as laser ranging technology, photoelectric detection technology, precision machinery technology, computer and control technology, etc. It has the characteristics of high precision, high efficiency, real-time tracking measurement, quick installation, and easy operation. It is suitable for large-size workpiece assembly measurement. During measurement, the laser needs to be shot into the target ball for measurement. The target ball is an indispensable part of the laser tracker.

[0003] When using a laser tracker for measurement, the operator is generally required to hold a target ball for measurement. There are many handheld target ball measuring devices on the market, as well as some target ball fixing devices, which achieve measurement by fixing the target ball on the object being measured. These target ball measuring devices cannot automatically determine the contact status with the measured parts and cannot be integrated with automated measurement equipment such as robots. It can be seen that the existing target ball devices cannot meet the needs of using laser trackers for high-precision automated contact measurement of parts. Summary of the invention

[0004] The purpose of the present invention is to provide a device for automatically contacting and measuring a target ball with a laser tracker, which can realize automatic contact measurement of the laser tracker without manual operation and improve work efficiency.

[0005] In order to achieve the above-mentioned object, one aspect of the present invention provides a laser tracker automatic contact measurement target ball device, comprising a target ball, an extension rod unit, an intermediate connecting seat, a bottom guide base and a data processing unit, wherein the target ball is mounted on the extension rod unit, the extension rod unit is connected to the intermediate connecting seat, the intermediate connecting seat is connected to the bottom guide base, and the data processing unit is mounted on both sides of the bottom guide base;

[0006] The extension rod unit includes a guide rod, a ball bearing, a compression spring and a spring adjustment end cap, wherein the target ball is connected to the guide rod extending from the extension rod unit through a thread, the guide rod inside the extension rod unit is connected to the ball bearing, the compression spring is inserted into the lower end of the guide rod, the spring adjustment end cap abuts against the compression spring, the compression spring abuts against the lower end of the guide rod, and the bottom of the guide rod is matched with the spring adjustment end cap through a threaded hole;

[0007] The intermediate connecting seat comprises a first displacement sensor and a connecting seat housing. One end of the connecting rod of the first displacement sensor is matched with the tail of the guide rod through a thread. The first displacement sensor can measure the displacement generated when the target ball is in axial contact with the measured object.

[0008] The bottom guide base includes a ball head, a ball head seat, a spring mounting seat, a spring, a second displacement sensor, and a spring adjustment cover, wherein the center hole below the ball head matches the outer contour of the ball head seat boss, the connecting seat shell of the intermediate connecting seat is fixed to the ball head by a threaded connection, the bottom of the ball head seat is in contact with the top plane of the spring mounting seat, the spring is inserted into the spring mounting seat and pressed onto the spring adjustment cover, and the second displacement sensor is installed in the inner hole of the spring mounting seat, and the second displacement sensor can measure the displacement generated when the target ball is in radial contact with the target to be measured.

[0009] Preferably, the extension rod unit further comprises a gland, a compression ring, a clamping tube, a spring, a spring locking nut, and a ball bearing compression nut.

[0010] Among them, the spring piece is installed on the shoulders of the upper and lower ends of the guide rod, the pressure cover is threadedly connected to the clamping cylinder, the pressure ring presses the outer edge of the spring piece, the spring piece locking nut presses the inner edge of the spring piece, the ball bearing clamping nut cooperates with the thread inside the clamping cylinder to fix the ball bearing, and the outer ring of the spring adjustment end cover is threadedly connected to the clamping cylinder.

[0011] Preferably, the intermediate connecting seat also includes a sensor mounting seat, the first displacement sensor is inserted into the middle hole of the sensor mounting seat, and the side of the sensor mounting seat has two symmetrical threaded through holes along the circumferential direction. The sensor is positioned by screwing a set screw into the threaded through hole to press against the first displacement sensor, and the sensor mounting seat and the connecting seat housing are fixed by screws.

[0012] Preferably, the bottom guide base further comprises a spherical ball bearing, a ball head pressure cover, a ball head upper seat, a ball head lower seat, a ball bearing, a ball bearing pressure cover, a guide housing, an intermediate guide sleeve, a connecting seat and a connecting plate.

[0013] Among them, the ball head is installed in the spherical ball bearing, the ball head pressure cover is connected to the ball head upper seat, the ball head upper seat is connected to the ball head lower seat, and is used to install the spherical ball bearing, the upper end of the guide shell is connected to the ball head lower seat, the lower end of the guide shell is connected to the connecting disk, the outer ring is matched with the inner ring of the ball bearing, the outer ring of the ball bearing is matched with the inner hole of the middle guide sleeve, the ball bearing pressure cover is fixedly connected to the middle guide sleeve to fix the ball bearing, the connecting rod of the second displacement sensor is connected to the connecting seat through threads, and the connecting seat is fixed to the connecting disk.

[0014] Preferably, a through hole is provided on the connection disk, and the connection disk is fixed to the mechanical arm through the through hole. An aviation interface is provided on the lower seat of the ball head for connecting with the host computer.

[0015] The device for automatically contacting and measuring a target ball with a laser tracker according to the above aspect of the present invention can realize automatic contact measurement with a laser tracker without manual operation, thereby improving work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solution of the present invention, the following briefly introduces the drawings used in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work:

[0017] Figure 1 This is a general structural diagram of a laser tracker automatic contact measurement target ball device according to an embodiment of the present invention;

[0018] Figure 2 is a structural cross-sectional view of an extension rod unit according to an embodiment of the present invention;

[0019] Figure 3 A structural cross-sectional view of an intermediate connecting seat according to an embodiment of the present invention;

[0020] Figure 4 The figure is a structural cross-sectional view of a bottom guide base according to an embodiment of the present invention.

[0021] Among them, 1-bottom guide base; 2-data processing unit; 3-middle connecting seat; 4-extension rod unit; 5-target ball; 40-guide rod; 41-pressure cover; 42-pressure ring; 43-bead bearing; 44-clamping tube; 45-spring; 46-compression spring; 47-spring locking nut; 48-bead bearing compression nut; 49-spring adjustment end cover; 30-connecting seat shell; 31-sensor mounting seat; 32-first displacement sensor device; 100-ball head; 101-spherical ball bearing; 102-ball head pressure cover; 103-ball head upper seat; 104-ball head lower seat; 105-ball head seat; 106-spring mounting seat; 107-spring; 108-second displacement sensor; 109-ball bearing; 110-ball bearing pressure cover; 111-spring adjustment pressure cover; 112-guide housing; 113-middle guide sleeve; 114-connecting seat; 115-connecting plate. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] One embodiment of the present invention provides a laser tracker automatic contact measurement target ball device, such as Figure 1As shown, the laser tracker automatic contact measurement target ball device of the embodiment of the present invention includes a target ball 5, an extension rod unit 4, an intermediate connecting seat 3, a bottom guide base 1 and a data processing unit 2. A corner cube prism is installed on the target ball 5 to receive and reflect the laser emitted by the laser tracker. The target ball 5 is installed on the extension rod unit 4, the extension rod unit 4 is connected to the intermediate connecting seat 3, the intermediate connecting seat 3 is connected to the bottom guide base 1, and the data processing unit 2 is installed on both sides of the bottom guide base 1. The target ball 5 is connected to the guide rod 40 extending from the extension rod unit 4 by threading, the guide rod 40 inside the extension rod unit 4 is connected to the ball bearing 43, the extension rod unit 4 is fixedly connected to the intermediate connecting seat 3 by screws, and the data processing unit 2 and the bottom guide base 1 are fixed by screws. The data processing unit can be used to collect data from the target ball device, including the time difference between laser emission and reception, the intensity of the laser signal, and the position information of the target ball.

[0024] like Figure 2 As shown, the extension rod unit 4 includes a guide rod 40, a pressure cap 41, a pressure ring 42, a ball bearing 43, a clamping tube 44, a spring 45, a compression spring 46, a spring locking nut 47, a ball bearing clamping nut 48 and a spring adjustment end cap 49. The spring 45 is installed on the shaft shoulders at the upper and lower ends of the guide rod 40, the pressure cap 41 is threadedly connected to the clamping tube 44, the pressure ring 42 presses against the outer edge of the spring 45, the spring locking nut 47 presses against the inner edge of the spring 45, and the ball bearing clamping nut 48 cooperates with the thread inside the clamping tube 44 to fix the ball bearing 43. The compression spring 46 is inserted into the lower end of the guide rod 40, the spring adjustment end cap 49 presses against the compression spring 46, and the compression spring 46 presses against the locking nut connected to the lower end of the guide rod 40 by thread. There is a threaded hole at the bottom of the guide rod 40, and the threaded hole cooperates with the spring adjustment end cap 49. The outer ring of the spring adjustment end cap 49 is threaded and cooperates with the clamping tube 44 by threaded connection.

[0025] like Figure 3 As shown, the intermediate connection seat 3 includes a connection seat shell 30, a sensor mounting seat 31 and a first displacement sensor 32. The cylindrical first displacement sensor 32 is inserted into the middle hole of the sensor mounting seat 31. The first displacement sensor 32 can measure the displacement generated when the target ball 5 is in axial contact with the measured object. There is a threaded hole at the tail of the guide rod 40, and one end of the connecting rod of the first displacement sensor 32 has a thread that matches the threaded hole of the guide rod 40. There are two symmetrical threaded through holes along the circumferential direction on the side of the sensor mounting seat 31. The set screw is screwed into the threaded through hole to resist the first displacement sensor 32 to realize the positioning of the sensor. The sensor mounting seat 31 is fixed to the connection seat shell 30 by screws.

[0026] like Figure 4As shown, the bottom guide base 1 includes a ball head 100, a spherical ball bearing 101, a ball head pressure cover 102, a ball head upper seat 103, a ball head lower seat 104, a ball head seat 105, a spring mounting seat 106, a spring 107, a second displacement sensor 108, a ball bearing 109, a ball bearing pressure cover 110, a spring adjustment pressure cover 111, a guide housing 112, an intermediate guide sleeve 113, a connecting seat 114 and a connecting plate 115.

[0027] The ball head 100 is installed in the spherical ball bearing 101, the center hole below the ball head 100 matches the outer contour of the boss of the ball head seat 105, the ball head pressure cover 102 is connected to the ball head upper seat 103 by bolts, the ball head upper seat 103 is connected to the ball head lower seat 104 by bolts, and is used to install the spherical ball bearing 101, the upper end of the guide housing 112 is connected to the ball head lower seat 104 by bolts, the lower end of the guide housing 112 is connected to the connecting plate 115 by bolts, the bottom of the ball head seat 105 is in contact with the top plane of the spring mounting seat 106, and the spring The spring 107 is inserted into the spring mounting seat 106 to press the spring 107 onto the spring adjustment gland 111. The second displacement sensor 108 is installed in the inner hole of the spring mounting seat 106. The outer ring matches the inner ring of the bead bearing 109. The outer ring of the bead bearing 109 matches the inner hole of the intermediate guide sleeve 113. The bead bearing gland 110 is fixedly connected with the intermediate guide sleeve 113 by screws to fix the bead bearing 109. The connecting rod of the second displacement sensor 108 is threadedly connected with the connecting seat 114, and the connecting seat 114 is fixed by screws and a connecting plate 115. The second displacement sensor 108 can measure the displacement generated when the target ball 5 is in radial contact with the measured object.

[0028] The intermediate connecting seat 3 is installed on the ball head 100 inside the bottom guide base 1. The lower end of the connecting seat shell 30 of the intermediate connecting seat 3 is turned with an external thread. The ball head 100 inside the bottom guide base 1 has a threaded hole. The connecting seat shell 30 is fixed to the ball head 100 through a threaded connection.

[0029] The method for using the laser tracker automatic contact measurement target ball device of the embodiment of the present invention is as follows: there is a through hole on the connection plate 115, and the connection plate 115 is fixed to the mechanical arm through the through hole. The mechanical arm drives the laser tracker automatic contact measurement target ball device to approach the measured target, and connects the aviation interface on the ball head lower seat 104 to the host computer, and the host computer reads the displacement data of the first displacement sensor 32 and the second displacement sensor 108 in real time. When the target ball 5 is in axial contact with the measured target, the target ball 5 transmits the displacement to the first displacement sensor 32 through the guide rod 40; when the target ball 5 is in radial contact with the measured target, the ball head 100 generates a rotational motion, which drives the ball head seat 105 to change its displacement, and transmits the displacement to the second displacement sensor 108 through the spring mounting seat 106. When the reading of the first displacement sensor 32 or the second displacement sensor 108 is greater than the set threshold, it can be determined that the target ball is in close contact with the measured target. At this time, the mechanical arm stops moving, and the laser tracker collects data. The compression spring 46 in contact with the guide rod 40 and the spring 107 in contact with the spring mounting seat 106 allow the entire device to have a certain elasticity, and a slight displacement occurs after the target ball contacts the object to be measured. At this time, the elastic force generated by the spring under the slight displacement ensures that the target ball and the object to be measured are in close contact.

[0030] In summary, the laser tracker automatic contact measurement target ball device of the embodiment of the present invention can be installed on a robotic arm to form an automated measurement system with the laser tracker. The contact status with the measured component can be detected by the internally installed displacement sensor, thereby realizing automatic contact measurement of the laser tracker. Manual operation of the staff is not required, thereby improving work efficiency.

[0031] The above description is only by way of illustration of certain exemplary embodiments of the present invention. It is undoubted that those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A laser tracker automatic contact measurement target ball device, characterized in that: It includes a target ball, an extension rod unit, an intermediate connecting seat, a bottom guide base and a data processing unit, wherein the target ball is mounted on the extension rod unit, the extension rod unit is connected to the intermediate connecting seat, the intermediate connecting seat is connected to the bottom guide base, and the data processing unit is mounted on both sides of the bottom guide base; The extension rod unit includes a guide rod, a ball bearing, a compression spring and a spring adjustment end cap, wherein the target ball is connected to the guide rod extending from the extension rod unit through a thread, the guide rod inside the extension rod unit is connected to the ball bearing, the compression spring is inserted into the lower end of the guide rod, the spring adjustment end cap abuts against the compression spring, the compression spring abuts against the lower end of the guide rod, and the bottom of the guide rod is matched with the spring adjustment end cap through a threaded hole; The intermediate connecting seat comprises a first displacement sensor and a connecting seat housing. One end of the connecting rod of the first displacement sensor is matched with the tail of the guide rod through a thread. The first displacement sensor can measure the displacement generated when the target ball is in axial contact with the measured object. The bottom guide base includes a ball head, a ball head seat, a spring mounting seat, a spring, a second displacement sensor, and a spring adjustment cover, wherein the center hole below the ball head matches the outer contour of the ball head seat boss, the connecting seat shell of the intermediate connecting seat is fixed to the ball head by a threaded connection, the bottom of the ball head seat is in contact with the top plane of the spring mounting seat, the spring is inserted into the spring mounting seat and pressed onto the spring adjustment cover, and the second displacement sensor is installed in the inner hole of the spring mounting seat, and the second displacement sensor can measure the displacement generated when the target ball is in radial contact with the target to be measured.

2. The laser tracker automatic contact measurement target ball device according to claim 1, characterized in that: The extension rod unit also includes a gland, a compression ring, a clamping tube, a spring, a spring locking nut, and a ball bearing compression nut. Among them, the spring piece is installed on the shoulders of the upper and lower ends of the guide rod, the pressure cover is threadedly connected to the clamping cylinder, the pressure ring presses the outer edge of the spring piece, the spring piece locking nut presses the inner edge of the spring piece, the ball bearing clamping nut cooperates with the thread inside the clamping cylinder to fix the ball bearing, and the outer ring of the spring adjustment end cover is threadedly connected to the clamping cylinder.

3. The laser tracker automatic contact measurement target ball device according to claim 1 or 2, characterized in that: The intermediate connecting seat also includes a sensor mounting seat, the first displacement sensor is inserted into the middle hole of the sensor mounting seat, and the side of the sensor mounting seat has two symmetrical threaded through holes along the circumferential direction. The sensor is positioned by screwing the set screws into the threaded through holes to press against the first displacement sensor. The sensor mounting seat and the connecting seat housing are fixed by screws.

4. The laser tracker automatic contact measurement target ball device according to claim 1 or 2, characterized in that: The bottom guide base also includes a spherical ball bearing, a ball head pressure cover, a ball head seat, a ball head lower seat, a ball bearing, a ball bearing pressure cover, a guide housing, an intermediate guide sleeve, a connecting seat and a connecting plate. Among them, the ball head is installed in the spherical ball bearing, the ball head pressure cover is connected to the ball head upper seat, the ball head upper seat is connected to the ball head lower seat, and is used to install the spherical ball bearing, the upper end of the guide shell is connected to the ball head lower seat, the lower end of the guide shell is connected to the connecting disk, the outer ring is matched with the inner ring of the ball bearing, the outer ring of the ball bearing is matched with the inner hole of the middle guide sleeve, the ball bearing pressure cover is fixedly connected to the middle guide sleeve to fix the ball bearing, the connecting rod of the second displacement sensor is connected to the connecting seat through threads, and the connecting seat is fixed to the connecting disk.

5. The laser tracker automatic contact measurement target ball device as claimed in claim 4, characterized in that: A through hole is provided on the connection plate, and the connection plate is fixed on the mechanical arm through the through hole. An aviation interface is provided on the lower seat of the ball head for connecting with the upper computer.

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