CN103884251A - Focal length measuring device for irregular workpiece in process of laser machining - Google Patents

Abstract

The invention provides a focal length measuring device for laser processing of irregular workpieces, which includes a base, a height gauge, a height gauge rotating assembly, a lifting sliding block, and an angle ruler telescopic measuring head assembly; the height gauge is vertically and fixedly installed on the height gauge rotating assembly It can be rotated by the rotation assembly of the height gauge; the lifting sliding block is set on the height gauge and can slide up and down along the height gauge; the telescopic measuring head assembly of the angle gauge includes a fixed arm and a measuring arm, and the fixed arm is fixedly installed on the on the height gauge and parallel to the height gauge; the measuring arm includes a square clip, a square primary rod, a square secondary rod and a contact pressure head. The present invention is a combination measuring tool with all-round space and composite measurement, which combines the measurement principles of the traditional height gauge and angle gauge, and its function breaks through multiple limitations of the traditional height gauge and angle gauge in measuring azimuth, measurement range, and measurement materials , compact structure, easy disassembly and assembly, easy to use, high measurement accuracy.

Description

Laser processing focal length measuring device for irregular workpieces

technical field

The invention belongs to the field of laser processing, and in particular relates to a focal length measuring device for laser processing of irregular workpieces.

Background technique

Laser processing technology is a technology that uses the characteristics of the interaction between laser beams and substances to cut, weld, surface treat, drill, and micro-process materials (including metals and non-metals). As an advanced manufacturing technology, laser processing has been widely used in important sectors of the national economy such as automobiles, electronics, electrical appliances, aviation, metallurgy, and machinery manufacturing. It has played an increasingly important role in improving product quality, labor productivity, automation, pollution-free, and reducing material consumption. important role.

During laser processing, before laser beam scanning, it is generally required to measure and know the focal length of each place on the laser scanning processing path in advance, so that the laser beam is always focused on the surface of the workpiece during scanning movement. For workpieces with regular shapes, such as cuboids, spheres, cylinders, etc., the traditional measurement method of focal length is mainly based on the principle of height gauge and angle ruler. As long as the focal length value of some feature points on the surface of the workpiece is measured, the remaining positions to be measured can be It is sufficient to calculate according to the regular geometric shape of the workpiece.

However, for some irregular workpieces with special shapes and sizes, especially special-shaped free-form surface workpieces or spliced workpieces without precise fitting equations, it is necessary to pre-intensively measure the focal length of each part of the processing path before starting processing. For this kind of special-shaped workpiece, it is very inconvenient to use ordinary measuring tools to measure, and it is even impossible to achieve accurate measurement. For example, for a large irregular shape processing workpiece, it is not easy or can not be moved. When laser processing (such as welding, cladding, quenching, etc.) Due to the limitation of orientation and measurement range, it is impossible to measure; for the situation that the front of the workpiece is high and the rear is low, the height gauge of the traditional measuring tool is a horizontal probe structure, which will cause measurement interference, and the probe cannot measure the rear part; if The workpiece to be processed is a soft material (due to the non-mechanical contact force characteristics of laser processing, it is very common in the field of laser processing technology), the pressure contact measurement method of traditional measuring tools will deform the workpiece, and thus cannot achieve accurate measurement.

Contents of the invention

The present invention aims at the deficiencies of the above-mentioned prior art, and provides a laser processing focal length measuring device for irregular workpieces; Measurement.

The present invention is achieved through the following technical solutions:

A focal length measurement device for laser processing of irregular workpieces, comprising a base, a height gauge, a height gauge rotation assembly, a lifting sliding block, and an angle scale telescopic measuring head assembly;

The base is a platform structure with the bottom surface as a horizontal reference plane; the height gauge rotation assembly is arranged on the top of the base, and the rotation center axis of the height gauge rotation assembly is parallel to the normal line of the bottom surface;

The height gauge is vertically and fixedly installed on the height gauge rotation assembly, parallel to the normal line of the bottom surface, and can be driven by the height gauge rotation assembly to rotate from 0 to 360 degrees;

The lifting and sliding block is set on the height gauge, and can slide up and down along the height gauge, and the sliding direction is parallel to the normal line of the bottom surface;

The lifting sliding block is provided with a position locking mechanism for fixing the relative position of the lifting sliding block and the height gauge;

The telescopic measuring head assembly of the angle ruler includes a fixed arm and a measuring arm;

The fixed arm is fixedly installed on the lifting sliding block, and is parallel to the height gauge, so that the telescopic measuring head assembly of the angle ruler can be driven by the lifting sliding block to move up and down;

The measuring arm includes a square clip, a square primary rod, a square secondary rod and a contact pressure head;

The square clip is connected to the fixed arm through a hinge, so that the entire measuring arm can rotate around the fixed arm within the range of 0 to 180 degrees, and its central axis of rotation is perpendicular to the normal line of the bottom surface;

A rotation angle sensor and a display are also installed on the square clip, and the rotation angle sensor and the display are respectively used to measure and display the angle between the measuring arm and the positive direction of the height gauge;

One end of the first-stage rod of the square is fixed on the clip of the square, and the other end is connected with the second-stage rod of the square. The second-stage rod of the square can slide along the inner cavity of the first-stage rod of the square to realize the telescopic change of the length of the measuring arm; A scale scale is marked on the first-level pole of the square and the second-level pole of the square;

The contact pressure head is fixed on the end of the secondary rod of the square, the contact pressure head includes a semicircular pressure arm and a photoelectric switch, and a contact connected to the end of the semicircle pressure arm;

A spring is set on the contact, and a contact switch is arranged at the end of the contact. When the contact touches the surface of the object to be measured and the spring is compressed, the contact switch sends out a switching signal;

The light emitting source and light receiver of the photoelectric switch are respectively arranged on the bottom of the inner surface of the semicircular pressing arm and the inner surface of the contact. When the light between the light emitting source and the light receiver is blocked by the object to be measured, the photoelectric The switch sends out a digital signal.

Preferably, the rotation assembly of the height gauge includes a rotating disk, a worm gear and a driving disk, and a hand handle is installed on the driving disk; the driving disk is connected with the rotating disk through a worm gear; the rotating disk Extending out of the upper surface of the base, the drive plate extends out of the side of the base; the height gauge is vertically and fixedly installed on the rotating disc.

The present invention has following beneficial effects:

1. The present invention is a combination measuring tool with all-round space and compound measurement, which combines the measurement principles of traditional height gauges and angle gauges, and its functions break through the many limitations of traditional height gauges and angle gauges in measuring azimuth, measurement range, and measurement materials. There are three limitations, compact structure, convenient disassembly and assembly, easy to use, and high measurement accuracy.

2. When the traditional height gauge measures different directions, it needs to move or rotate the base to reinstall the measuring tool, which will cause large installation space requirements for the base, inconvenient placement, and base reference errors caused by multiple transpositions (the position of the base will actually be different) roughness and flatness errors); the present invention adds a rotating table structure to the base, and through the hand-operated drive plate, the telescopic measuring head assembly of the height gauge and the angle gauge can be rotated as a whole, without re-installing the base, which changes the traditional height gauge. Insufficient base, no reference error caused by transposition, more convenient adjustment.

3. The measuring rod of the present invention is an angle ruler telescopic measuring head assembly structure. One fixed arm is fixedly installed on the lifting sliding block and is parallel to the normal line of the bottom surface. The other arm is a measuring arm, and the whole measuring arm can be wound around the fixed arm. Rotate within the range of 0 to 180 degrees, so that the measuring arm can protrude upward, horizontal or downward at the set angle. This structure solves the problem that the traditional height gauge measuring rod is fixed and protruding horizontally, which causes interference in the measurement of special-shaped workpieces; And the telescopic head assembly of the angle ruler adopts digital display mode, which is convenient for reading, accurate and reliable; the lifting and sliding block has its own locking mechanism, so that the relative position of the telescopic head assembly of the angle ruler and the height gauge can be locked, which is convenient for measurement.

4. The measuring arm of the angle ruler telescopic measuring head assembly in the present invention adopts a telescopic rod type with a scale, which greatly expands the measuring range.

5. The measuring head at the front end of the measuring arm of the present invention adopts a contact pressure head structure, which ensures good contact between the contact head and the surface of the workpiece when measuring hard materials, and accurate and reliable measurement; at the same time, the design of the semicircular pressure arm is also It can make the contact indenter bypass the tiny protruding obstacles near the point to be measured (especially practical when measuring shallow grooves), and measure workpieces with high front and low rear shape features in local small areas.

6. In the present invention, the inner end of the semicircular pressing arm adopts the design of photoelectric switch. When the workpiece to be tested is a thin sheet or flexible material, once the contactor touches the surface of the workpiece, the slight bending of the workpiece will immediately trigger the photoelectric switch. Obtain the current measurement value, the measurement takes into account the deformation of the workpiece under the external force of the probe, and the result is more accurate.

Description of drawings

Fig. 1 is the three-dimensional structural diagram of the focal length measuring device for laser machining of irregular workpieces according to the present invention;

Fig. 2 is the structural diagram of height gauge rotation assembly;

Fig. 3 is a structural diagram of an angle ruler telescoping probe assembly;

Fig. 4 is a structural diagram of the contact pressure head;

Fig. 5 is the measurement schematic diagram of the focal length measurement device for laser processing;

Fig. 6 is a measurement schematic diagram of a workpiece with a high front and a low rear;

The meanings of the symbols in the figure are as follows:

Base 1, height gauge 2, height gauge rotation assembly 3, lifting sliding block 4, fixed arm 5, measuring arm 6, rotating disk 31, worm gear transmission mechanism 32, driving disk 33, hand handle 34, locking screw 41 , Angle ruler clip 61, angle ruler primary lever 62, angle ruler secondary lever 63, contact pressure head 64, semicircle pressure arm 65, photoelectric switch 66, contact 67, spring 68.

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figures 1-4, the present invention provides a focal length measurement device for laser processing of irregular workpieces, including a base 1, a height gauge 2, a height gauge rotation assembly 3, a lifting sliding block 4 and an angle scale telescopic probe assembly ;

The base 1 is a platform structure with the bottom surface as the horizontal reference plane, and the surface roughness is less than Ra12.5. Hereinafter, the horizontal reference plane of the base 1 is simply referred to as the bottom surface.

The height gauge 2 is vertically and fixedly installed on the height gauge rotating assembly 3, parallel to the normal line of the bottom surface, and can be driven by the height gauge rotating assembly 3 to rotate 0-360 degrees. The height gauge rotation assembly 3 is arranged on the top of the base 1, and the relative installation orientation of the two requires that the rotation center axis of the height gauge rotation assembly 3 is parallel to the normal line of the bottom surface 1;

A preferred structure of the height gauge rotating assembly 3 is: comprising a rotating disc 31, a worm gear 32 and a drive disc 33, the drive disc 33 is equipped with a hand handle 34; The transmission mechanism 32 is connected with the rotating disk 31 . The rotating disk 31 extends out of the upper surface of the base 1 , and the height gauge 2 is vertically and fixedly mounted on the rotating disk 31 ; the driving disk 33 extends out of the side of the base 1 . Rotate the crank handle 34 by hand during operation to drive the rotating disk 31 to rotate, and then drive the height gauge 2 to rotate. Of course, the height gauge rotating assembly 3 can also adopt other structures, such as gear set transmission, etc., as long as it can drive the height gauge 2 to rotate 0-360 degrees.

The lifting and sliding block 4 is set on the height gauge 2, and can slide up and down along the height ruler 2, and its sliding direction is parallel to the normal line of the bottom surface; The position locking mechanism relative to the height gauge 2 can be realized by screwing into the two locking screws 41 of the lifting and sliding block 4. Of course, other locking mechanisms can also be used, and the present invention is not limited thereto.

The telescopic measuring head assembly of the angle ruler includes a fixed arm 5 and a measuring arm 6. The fixed arm 5 is fixedly mounted on the lifting sliding block 4 and is parallel to the height ruler 2, that is, parallel to the normal line of the bottom surface, so that the angle ruler The telescopic probe assembly as a whole can be driven by the lifting and sliding block 4 to move up and down.

The measuring arm 6 includes a square clip 61 , a square primary rod 62 , a square secondary rod 63 and a contact pressure head 64 .

The square clip 61 is connected to the fixed arm 5 through a hinge, so that the whole measuring arm 6 can rotate around the fixed arm 5 in the range of 0-180 degrees, and its central axis of rotation is perpendicular to the normal line of the bottom surface.

A rotation angle sensor and a display are installed on the angle clip 61 , and the rotation angle sensor and display are respectively used to measure and display the angle between the measuring arm 6 and the positive direction of the height gauge 2 .

One end of the square primary rod 62 is fixed on the square clip 61, and the other end is connected with the square secondary rod 63, and the square secondary rod 63 can slide along the cavity of the square primary rod 62 to realize the measuring arm 6. The expansion and contraction of length; The scale scale is marked on the first-level rod 62 of the square and the second-level rod 63 of the square, which can obtain the amount of expansion and contraction; The sum of the lengths of the indenters 64 plus the telescopic variation can calculate the length from the measuring point to the hinge point between the square clip 61 and the fixed arm 5 .

The contact pressure head 64 is fixed on the end of the square secondary rod 63, the contact pressure head 64 includes a semicircle pressure arm 65 and a photoelectric switch 66, and a contact 67 connected to the end of the semicircle pressure arm 65, A spring 68 is sleeved on the contact 67, and a contact switch is provided. When the contact contacts the surface of the object to be measured and the spring 68 is compressed, the contact switch sends a switch signal; the light emitting source and the light receiver of the photoelectric switch 66 They are oppositely arranged on the bottom of the inner surface of the semicircular pressing arm 65 and the inner surface of the contact 67. The distance between the light emitting source and the light receiver can be 0.1 mm to 10 mm according to the measurement accuracy requirements. When the distance between the light emitting source and the light receiver When the light in the room is blocked by the measured object, the photoelectric switch sends out a switching signal.

The process of using the above-mentioned laser processing focal length measurement device for focal length measurement is:

First, rotate the hand handle 34 to drive the rotating disk 31 and the height gauge 2 to rotate to a suitable position; then adjust the height gauge 2 to the vicinity of the height of the point to be measured, and finally adjust the measuring arm 6 of the angle gauge telescopic probe assembly to make it The contact 67 on the contact pressure head 64 is in contact with the point to be measured. At this time, the height value H of the height gauge 2 is read, and the angle value α of the telescopic measuring head assembly of the angle ruler is calculated; by calculating the height value H and the angle value α, you can Obtain the height of the point to be measured on the workpiece, and then realize the measurement of the processing focal length.

As shown in Figure 5, through the height value H and the angle value α, the specific method for calculating the height Z of the point to be measured on the workpiece is: Z=H+Lcosα, where L is the length of the measuring arm 6, and the angle value α is the measurement arm 6 The angle between it and the positive direction of height gauge 2.

As shown in Figure 6, the two measurement points T1 and T2 in the figure are the situation that the front is high and the rear is low, and traditional measurement tools will interfere and cannot be measured; but the laser processing focal length measurement device described in the present invention can be used Realize convenient measurement, where the height of measuring point T1 is Z1=H1+L1cosα ₁ , the height of measuring point T2 is Z2=H2+L2cosα ₂ , and the height difference between the two points is Z1-Z2. The situation in Fig. 6 is also applicable to the situation where there is no measurement reference point, such as when the workpiece reference plane is not on the same horizontal plane as the installation reference plane of the laser processing focal length measuring device according to the present invention, as long as a point on the workpiece is arbitrarily selected As the height reference point, it may be set as Z1, and then the height value Z2 measured at the subsequent measurement point, by calculating Z1-Z2, the height difference of other positions on the workpiece relative to the height reference point can be obtained.

It will be obvious to those skilled in the art that the present invention may be modified in various ways and such modifications are not to be regarded as departing from the scope of the present invention. All such modifications obvious to those skilled in the art are intended to be included within the scope of this claim.

Claims (2)

1. A focal length measuring device for laser processing of irregular workpieces, characterized in that it comprises a base, a height gauge, a height gauge rotating assembly, a lifting slide block and an angle scale telescopic measuring head assembly; The base is a platform structure with the bottom surface as a horizontal reference plane; the height gauge rotation assembly is arranged on the top of the base, and the rotation center axis of the height gauge rotation assembly is parallel to the normal line of the bottom surface; The height gauge is vertically and fixedly installed on the height gauge rotation assembly, parallel to the normal line of the bottom surface, and can be driven by the height gauge rotation assembly to rotate from 0 to 360 degrees; The lifting and sliding block is set on the height gauge, and can slide up and down along the height gauge, and the sliding direction is parallel to the normal line of the bottom surface; The lifting sliding block is provided with a position locking mechanism for fixing the relative position of the lifting sliding block and the height gauge; The telescopic measuring head assembly of the angle ruler includes a fixed arm and a measuring arm; The fixed arm is fixedly installed on the lifting sliding block, and is parallel to the height gauge, so that the telescopic measuring head assembly of the angle ruler can be driven by the lifting sliding block to move up and down; The measuring arm includes a square clip, a square primary rod, a square secondary rod and a contact pressure head; The square clip is connected to the fixed arm through a hinge, so that the entire measuring arm can rotate around the fixed arm within the range of 0 to 180 degrees, and its central axis of rotation is perpendicular to the normal line of the bottom surface; A rotation angle sensor and a display are also installed on the square clip, and the rotation angle sensor and the display are respectively used to measure and display the angle between the measuring arm and the positive direction of the height gauge; One end of the first-stage rod of the square is fixed on the clip of the square, and the other end is connected with the second-stage rod of the square. The second-stage rod of the square can slide along the inner cavity of the first-stage rod of the square to realize the telescopic change of the length of the measuring arm; A scale scale is marked on the first-level pole of the square and the second-level pole of the square; The contact pressure head is fixed on the end of the secondary rod of the square, and the contact pressure head includes a semicircle pressure arm and a photoelectric switch, and a contact connected to the end of the semicircle pressure arm; A spring is set on the contact, and a contact switch is provided at the end of the contact. When the contact touches the surface of the object to be measured and the spring is compressed, the contact switch sends out a switching signal; The light emitting source and light receiver of the photoelectric switch are respectively arranged on the bottom of the inner surface of the semicircular pressing arm and the inner surface of the contact. When the light between the light emitting source and the light receiver is blocked by the object to be measured, the photoelectric The switch sends out a digital signal. 2. The focal length measuring device for laser processing of irregular workpieces according to claim 1, wherein the height scale rotating assembly includes a rotating disk, a worm gear mechanism and a driving disk, and a hand crank is installed on the driving disk handle; the drive plate is connected to the rotating plate through a worm gear transmission mechanism; the rotating plate extends out of the upper surface of the base, and the driving plate extends out of the side of the base; the height gauge is vertically and fixedly installed on the rotating plate.

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