CN106891339B - Grinding robot with gravity compensation and grinding method thereof - Google Patents

Abstract

The present invention relates to a kind of milling robot and its polishing process with gravity compensation, this method comprises the following steps: according to the polishing track planned, presetting multiple target points is P₁、P₂……P_nAnd multistage orbit segment is P₁‑P₂、P₂‑P₃……P_n‑1‑P_n, obtain the target-angle A of each target point；According to the target-angle A of each target point, the default angle of inclination B of every section of orbit segment is calculated；Obtain the quality m of default floatation element and default angle of inclination B and preset polishing power F in conjunction with every section of orbit segment_N, the driving force F of every section of orbit segment is calculated_{It drives}；And polish along polishing track, during the grinding process, apply corresponding driving force F on every section of orbit segment_{It drives}.The milling robot with gravity compensation and its polishing process, which are avoided that milling tools and are polished between workpiece, occurs rigid collision, improves the yield rate for being polished workpiece.

Description

Grinding robot with gravity compensation and grinding method thereof

technical field

The invention relates to the technical field of workpiece grinding, in particular to a grinding robot with gravity compensation and a grinding method thereof.

Background technique

The traditional robot automatic grinding process (also called automatic polishing process) is based on the trajectory of the robot taught by the teach pendant or off-line programming based on the designed workpiece standard geometric model. The subsequent workpiece grinding trajectory is based on this fixed trajectory. .

However, in the actual grinding process, due to manufacturing reasons, the geometric size of each workpiece will be different from the original design standard geometric model, and its own size and flash burrs will be different, which will affect the grinding quality. When encountering a large flash burr, the grinding tool will drop sharply or get stuck due to a large grinding pressure; when encountering a small flash burr, the grinding tool may not be able to touch the tool surface, Eventually, the grinding quality of some workpieces will be unsatisfactory, and even the workpieces will be scrapped. At the same time, when polishing a curved surface, due to the change of the curvature of the surface, the normal polishing force of the traditional automatic polishing process grinding head acting on the surface cannot be accurately controlled following the change of the curvature of the surface.

Contents of the invention

Based on this, it is necessary to provide a grinding robot with gravity compensation and its grinding method, which allows a certain degree of misalignment between the grinding tool and the workpiece to be polished, and can avoid rigid collision between the grinding tool and the workpiece to be polished. The normal polishing force of the head acting on the surface can be accurately controlled following the change of the curvature of the surface, thereby improving the stability of the polishing quality and the yield of the polished workpiece.

Its technical scheme is as follows:

A grinding robot with gravity compensation, characterized in that it includes a floating connection mechanism, and also includes a movable operating head, an inclination sensor and a controller;

The floating connection mechanism includes a first connection assembly, and the first connection assembly includes a first outer connecting plate, a first inner connecting plate opposite to the first outer connecting plate, and at least two guide rods arranged at intervals. An external connection part is provided on the outside of an external connection plate, and one end of all the guide rods is fixed to the first external connection plate, and the other end is fixed to the first internal connection plate; the second connection assembly, the second connection assembly can be opposite Sliding on the first outer connection plate, the second connection component includes a movable second inner connection plate, a second outer connection plate opposite to the second inner connection plate, and at least two connecting rods arranged at intervals, the second The inner connecting disc is arranged between the first outer connecting disc and the first inner connecting disc, and is slidably connected with all the guide rods, one end of all the connecting rods is fixed to the second inner connecting disc, and the other end is connected to the second inner connecting disc. The second external disk is fixed, and the second external disk is provided with a connecting portion; and the first telescopic device is fixed on the first external disk, and the first telescopic device is provided with A telescopic rod that can float to adjust the output pressure, one end of the telescopic rod is fixedly connected to the second inner connection plate;

The operation head is fixedly connected to the external connection part, the inclination sensor is installed on the first external connection plate, the controller can control the operation head to move according to the preset grinding track, and the controller can obtain The inclination data detected by the inclination sensor and the output pressure of the expansion rod of the first expansion device are controlled.

When the above-mentioned grinding robot is in use, the second external disc is installed and fixed with the grinding tool through the connecting part; when performing grinding work, the grinding head of the grinding tool is in flexible contact with the workpiece to be polished. When encountering a large flash burr, the telescopic rod When the extrusion force increases, the telescopic rod can shrink according to the preset output pressure so that the contact force between the grinding head and the workpiece to be polished can adapt to the change of the workpiece surface; when encountering small flash burrs, the telescopic rod can When the extrusion force is reduced, the telescopic rod is extended according to the preset output pressure so that the contact force between the grinding head and the workpiece to be polished adapts to the change of the surface of the workpiece, so that the grinding head runs at a uniform speed during the grinding process and is ground The grinding and polishing quality of the workpiece is good and the stability is high. The grinding robot allows a certain degree of dislocation between the grinding tool and the workpiece to be polished, which can avoid rigid collision between the grinding tool and the workpiece to be polished, thereby improving the stability of the grinding quality and the yield of the workpiece to be polished.

The technical scheme is further described below:

In one of the embodiments, the second external connection plate is provided with a mounting body protruding outwardly on the outside of the second external connection plate and a mounting structure that cooperates with the mounting body to form the connecting portion, so The mounting body is provided with a matching hole, and the mounting structure includes a locking piece that can be elastically reset and penetrates through the side wall of the matching hole, and a positioning piece fixed on the outside of the second external connection plate.

In one of the embodiments, it also includes a second telescopic device for controlling the expansion and contraction of the locking member, the second telescopic device includes a cone that can telescopically move in the matching hole, and the large end of the cone is close to The second inner connection plate is arranged, and the big end of the cone is press-fitted with one end of the locking member.

The technical solution also provides a grinding method with gravity compensation applied to the above grinding robot with gravity compensation, including the following steps:

According to the planned grinding trajectory, the preset multiple target points are P ₁ , P ₂ ... P _n and the multi-segment trajectory segments are P ₁ -P ₂ , P ₂ -P ₃ ... P _n-1 -P _n , Obtain the target inclination angle A of each target point;

According to the target inclination A of each of the target points, the preset inclination B of each track segment is calculated;

Obtaining the mass m of the preset floating component, and combining the preset inclination B of each track segment and the preset grinding force F _N , calculating the _driving force F of each track segment;

Grinding along the grinding track, during the grinding process, applying a corresponding _driving force F on each track segment;

Wherein, the target inclination A is the angle between F _N and the horizontal plane, and -90°≤A≤90°, the target inclination A is positive when it is above the horizontal plane, the target inclination A and the horizontal plane coincide to be zero, and the target inclination A is at Below the horizontal plane is negative; the trajectory segment is the trajectory line between two adjacent target points, n is a positive integer, and n≥4; F _N is the normal positive pressure of the grinding head on the workpiece surface, when When F _drive and F _N are in the same direction, F _drive = F _N -mgsin B, when F _drive and F _N are in the opposite direction, F _drive = |mgsin B|-F _N .

When using the above-mentioned grinding method with gravity compensation, first plan the grinding trajectory according to the outer surface of the workpiece to be polished, and preset multiple target points and multiple trajectory segments according to the grinding trajectory, and perform offline programming. The controller controls the operation head according to the grinding trajectory. Move and detect the target inclination angle corresponding to each target point; then calculate the preset inclination angle B of each track segment according to the target inclination angle A of each target point; obtain the quality of the preset floating component at the same time m, combined with the preset inclination angle B of each track segment and the preset grinding force F _N , calculate the _driving force F of each track segment, and perform secondary programming, so that during the grinding process, A corresponding _driving force F with gravity compensation can be applied on each track segment. The grinding method with gravity compensation allows a certain degree of dislocation between the grinding tool and the workpiece to be polished, which can avoid rigid collision between the grinding tool and the workpiece to be polished, and at the same time, the gravity compensation of the floating component is performed to eliminate the impact of the gravity of the floating component on the grinding quality. interference, further improving the stability of the grinding quality and yield of the workpiece being polished.

The technical scheme is further described below:

In one embodiment, the preset inclination angle B of the trajectory segment is equal to the average value of the sum of target inclination angles A of two adjacent target points.

In one of the embodiments, when grinding is performed on one of the trajectory segments P _i -P _i+1 , the corresponding two target points are P _i and P _i+1 , and the target inclination angle of the target point P _i is A _i , the target inclination angle of the target point P _i+1 is A _i+1 ;

When F _drive is in the same direction as F _N , the drive force corresponding to the trajectory segment P _i -P _i+1

F _flooding ＝F _N －mgsin B＝F _N －mgsin[(A _i +A _i+1 )/2]; when F _flooding and F _N reverse,

F= _∣mgsin B∣－F _N ＝∣mgsin[(A _i +A _i+1 )/2]∣－F _N ; where, i is a positive integer.

In one of the embodiments, it also includes planning the grinding trajectory according to the change of the surface curvature of the workpiece to be ground.

In one embodiment, when the surface curvature of the grinding workpiece between two adjacent target points changes more, the length of the corresponding trajectory line between two adjacent target points becomes smaller.

In one of the embodiments, the change of the _driving force F is obtained by adjusting the direction, voltage or current of the proportional reversing valve.

In one of the embodiments, the required _driving force F for all trajectory segments corresponds to the direction, current I or voltage U of one proportional reversing valve respectively.

In one of the embodiments, during the grinding process along the grinding track, the _driving force F is preset to adjust the buffer time T when the _driving force F is changed.

Description of drawings

Fig. 1 is the flowchart of the polishing method with gravity compensation of the present invention;

Fig. 2 is the structural representation of grinding robot described in the present invention;

Fig. 3 is a three-dimensional structural schematic diagram of the floating connection mechanism of the present invention;

Fig. 4 is the schematic diagram of the control system of the grinding robot of the present invention;

Fig. 5 is a schematic diagram of the polishing work of the polishing robot according to the present invention;

Fig. 6 is a schematic front view of the floating connection mechanism of the present invention;

Fig. 7 is a half-sectional schematic diagram of A-A in Fig. 6;

Fig. 8 is a schematic structural diagram of the first connection assembly according to the present invention;

Fig. 9 is a schematic diagram of the assembly structure of the second connection assembly and the telescopic rod according to the present invention;

Fig. 10 is a schematic diagram of a grinding tool according to the present invention;

Fig. 11 is a schematic diagram of a floating connection mechanism with a dust-proof film according to the present invention;

Fig. 12 is a schematic diagram of force analysis of the grinding method with gravity compensation according to the present invention.

Explanation of reference signs:

100. First connection assembly, 110. First external connection plate, 120. First internal connection plate, 122. Cooperating through hole, 124. Misalignment through hole, 130. Guide rod, 200. Second connection assembly, 210, Second inner connection Connecting disc, 212, linear ball bearing, 220, second external connecting disc, 224, installation body, 202, matching hole, 204, connecting part, 230, connecting rod, 240, installation structure, 242, locking member, 244, positioning member , 300, first telescopic device, 310, telescopic rod, 400, second telescopic device, 410, cone, 500, connector, 510, connecting hole, 520, mating groove, 530, positioning hole, 600, dustproof Cap, 10, floating connection mechanism, 20, operating head, 30, inclination sensor, 40, controller, 50, power unit, 60, proportional reversing valve, 70, grinding tool, 72, grinding head, 80, robot movement mechanism , 90, grinding workpiece.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation methods. It should be understood that the specific embodiments described here are only used to explain the present invention, and do not limit the protection scope of the present invention.

It should be noted that when an element is referred to as being “fixed on”, “disposed on” or “installed on” another element, it may be directly on the other element or there may be an intervening element. When an element is considered to be "connected" to another element, it may be directly connected to the other element or there may be an intervening element at the same time; the specific way that one element is fixedly connected to another element can be realized through existing technologies, and will not be discussed here. To repeat it again, it is preferable to adopt a fixing method of threaded connection.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field of the invention. The terminology used herein in the description of the present invention is only for the purpose of describing specific embodiments, and is not intended to limit the present invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

The "first" and "second" mentioned in the present invention do not represent specific numbers and sequences, but are only used to distinguish names.

As shown in Figure 1, a kind of grinding method with gravity compensation according to the present invention comprises the following steps:

According to the planned grinding trajectory, the preset multiple target points are P ₁ , P ₂ ... P _n and the multi-segment trajectory segments are P ₁ -P ₂ , P ₂ -P ₃ ... P _n-1 -P _n , Obtain the target inclination angle A of each target point;

According to the target inclination A of each target point, calculate the preset inclination B of each track segment;

Obtaining the mass m of the preset floating component, and combining the preset inclination B of each track segment and the preset grinding force F _N , calculating the _driving force F of each track segment;

Grinding along the grinding track, during the grinding process, applying a corresponding _driving force F on each track segment;

Wherein, the target inclination A is the angle between F _N and the horizontal plane, and -90°≤A≤90°, the target inclination A is positive when it is above the horizontal plane, the target inclination A and the horizontal plane coincide to be zero, and the target inclination A is at Below the horizontal plane is negative; the trajectory segment is the trajectory line between two adjacent target points, n is a positive integer, and n≥4; F _N is the normal positive pressure of the grinding head on the workpiece surface, when When F _drive and F _N are in the same direction, F _drive = F _N -mgsin B, when F _drive and F _N are in the opposite direction, F _drive = |mgsin B|-F _N .

When using the above-mentioned grinding method with gravity compensation, first plan the grinding trajectory according to the outer surface of the workpiece to be polished, and preset multiple target points and multiple trajectory segments according to the grinding trajectory, and perform offline programming. The controller controls the operation head according to the grinding trajectory. Move and detect the target inclination angle corresponding to each target point; then calculate the preset inclination angle B of each track segment according to the target inclination angle A of each target point; obtain the quality of the preset floating component at the same time m, combined with the preset inclination angle B of each track segment and the preset grinding force F _N , calculate the _driving force F of each track segment, and perform secondary programming, so that during the grinding process, A corresponding _driving force F with gravity compensation can be applied on each track segment. The grinding method with gravity compensation allows a certain degree of dislocation between the grinding tool and the workpiece to be polished, which can avoid rigid collision between the grinding tool and the workpiece to be polished, and at the same time, the gravity compensation of the floating component is performed to eliminate the impact of the gravity of the floating component on the grinding quality. interference, further improving the stability of the grinding quality and yield of the workpiece being polished.

As shown in Figure 5 and Figure 12, it needs to be explained that during this process, due to the change of the grinding direction, the gravity interaction between the F _drive and the floating component results in a grinding force F _N , that is, when the grinding force F _N is constant, the F _drive The same power as the gravity of the floating component, F _driving as the driving force, the gravity of the floating component as resistance or F _driving as resistance, and the gravity of the floating component as the driving force, F _driving can be greater than zero or less than zero (that is, F _driving and F _N are the same forward or reverse). specific:

(1) As shown in Figure a in Figure 12, when the target inclination angle A is below the horizontal plane, A _< 0°, B<0 _° ; In the same direction as F _N , F _N = F _drive - |mgsin B | The range of grinding force F _N is [0, F _drive maximum value - | mgsin B |].

(2) As shown in Figure b in Figure 12, when the target inclination angle A is on the horizontal plane, A=0°, B=0°; F _drive is the power, the resistance is zero, F _drive and F _N are in the same direction, and the grinding force F _N = F _drive .

(3) As shown in Figure c and Figure d in Figure 12, when the target inclination angle A is above the horizontal plane, A>0°, B>0°; at this time, the gravity of the floating assembly is the power; when the grinding force F When _N >∣mgsinB∣, F _driving and F _N are in the same direction, F _N =∣mgsinB∣+F _driving ; when grinding force F _N <∣mgsinB∣, F _driving and F _N are opposite, F _N =∣mgsinB∣ -F _drive .

Further, the preset inclination angle B of the trajectory segment is equal to the average value of the sum of target inclination angles A of two adjacent target points. The curvature of the target points at both ends of the trajectory segment does not change much. Therefore, while obtaining a better compensation effect, the programming of the preset inclination angle of the trajectory segment is simplified, which can not only improve the programming efficiency, but also reduce the impact of the gravity change of the floating component on the grinding quality. influences. Specifically, when grinding is performed on one of the trajectory segments P _i -P _i+1 , the corresponding two target points are P _i and P _i+1 , the target inclination angle of the target point P _i is A _i , and the target point The target inclination angle of P _i+1 is A _i+1 ; when F _drive is in the same direction as F _N , the driving force F _drive corresponding to the trajectory segment P _i -P _i+1 =F _N -mgsin B=F _N - mgsin[(A _i +A _i+1 )/2]; when F _drive and F _N reverse, F _drive =∣mgsin B∣－F _N ＝∣mgsin[(A _i +A _i+1 )/2 ]∣－F _N ; where, i is a positive integer.

In the above embodiment, it also includes planning the grinding trajectory according to the change of the surface curvature of the workpiece to be polished, so as to obtain a more optimized target point and improve the grinding quality. Further, when the surface curvature of the grinding workpiece between two adjacent target points changes more, the length of the trajectory line between the corresponding two adjacent target points is smaller; similarly, when two The smaller the surface curvature of the grinding workpiece between adjacent target points is, the longer the corresponding trajectory line between two adjacent target points is. Therefore, combined with the setting of the preset inclination angle, the selection of the two target points needs to consider the influence of the change of the surface curvature of the polished workpiece on the optimized value, and reasonably preset the target points to obtain better grinding quality.

In the above embodiments, the change of the _driving force F is obtained by adjusting the voltage or current of the proportional reversing valve. Therefore, it is only necessary to set the output pressure of the telescopic rod to obtain the corresponding driving force F _drive , and it is easy to realize the adjustment of the driving force F _drive . Preferably, the _driving force F required by all trajectory segments corresponds to the current I or voltage U of a proportional reversing valve respectively, which is convenient for off-line programming control, avoids compensation according to the detection data during the detection process, and avoids data processing difficulties. Increase the cost of equipment; at the same time reduce the error caused by equipment delay. Further, during the grinding process along the grinding track, when the _driving force F is changing, the buffering time T for adjusting the preset _driving force F is also included. Therefore, a certain force action time should be given before each trajectory program, so that the force value when running to the target point is consistent with the predetermined value, so as to avoid the inconsistency between the change of the driving force and the change of the grinding trajectory.

As shown in Figures 2 to 5, the present invention also provides a grinding robot, including a floating connection mechanism 10, a movable operating head 20, an inclination sensor 30 and a controller 40;

The floating connection mechanism 10 includes: a first connection assembly 100, the first connection assembly 100 includes a first outer connecting plate 110, a first inner connecting plate 120 opposite to the first outer connecting plate 110, and at least two guide rods 130 arranged at intervals, The outer side of the first external connection disc 110 is provided with an external connection part (not labeled), and one end of all guide rods 130 is fixed with the first external connection disc 110, and the other end is fixed with the first internal connection disc 120; the second connection assembly 200, the second connection assembly 200 can slide relative to the first outer connection plate 110, the second connection assembly 200 includes a movable second inner connection plate 210, a second outer connection plate 220 opposite to the second inner connection plate 210, and at least two connecting rods 230 arranged at intervals , the second inner connecting disc 210 is arranged between the first outer connecting disc 110 and the first inner connecting disc 120, and is slidably connected with all the guide rods 130, one end of all the connecting rods 230 is fixed to the second inner connecting disc 210, and the other end is connected to the second inner connecting disc 210. The external disk 220 is fixed, and the second external disk 220 is provided with a connecting portion 204; and the first telescopic device 300, the first telescopic device 300 is fixed on the first external disk 110, and the first telescopic device 300 is provided with a floating adjustable output A telescopic rod 310 for pressure, one end of the telescopic rod 310 is fixedly connected with the second inner connecting disc 210;

The operating head 20 is fixedly connected to the external connection part, the inclination sensor 30 is installed on the first external connection plate 110, the controller 40 can control the operation head 20 to move according to the preset grinding track, and the controller 40 can obtain the inclination sensor 30 detected The inclination data and the output pressure of the telescopic rod 310 of the first telescopic device 300 are controlled.

As shown in Figures 2 to 5, when the above-mentioned grinding robot is in use, the second external disc 220 is installed and fixed with the grinding tool 70 through the connecting part 204; Contact, when encountering larger flash and burrs, the telescopic rod 310 can shrink according to the preset output pressure under the condition of increasing extrusion force to adapt the contact force between the grinding head 72 and the workpiece 90 to be polished Changes in the surface of the workpiece; when encountering small flash burrs, the telescopic rod 310 can be stretched according to the preset output pressure when the extrusion force is reduced, so that the grinding head 72 and the workpiece 90 to be polished The contact force of the contact force adapts to the change of the surface of the workpiece, so that the running speed of the grinding head 72 is uniform during the grinding process, and the grinding and polishing quality of the workpiece 90 to be polished is good and the stability is high. The grinding robot allows a certain degree of dislocation between the grinding tool 70 and the workpiece 90 to be polished, which can avoid rigid collision between the grinding tool 70 and the workpiece 90 to be polished, thereby improving the stability of the grinding quality of the workpiece 90 to be polished and the finished product. Rate.

As shown in Figures 3 to 4, in this embodiment, it also includes a power unit 50 that provides power for the first telescopic device 300 and a proportional reversing valve 60 that communicates with the power device 50 and the first telescopic device 300 respectively, and the controller 40 controls the output pressure of the telescopic rod 310 through the proportional reversing valve 60 .

Concretely, according to the outer surface shape of the workpiece 90 to be polished, the grinding trajectory planned by off-line programming, multiple target points and multi-section trajectory segments are set, and the controller 40 controls the operation head 20 to drive the inclination sensor 30 to detect the position of each target point. Target inclination A; then calculate the preset inclination B of each track segment according to the target inclination A of each target point; obtain the quality of the floating component composed of the second component, the grinding tool 70 and the telescopic rod 310 through the quality detector detection m, combined with the preset inclination angle B of each trajectory segment and the preset grinding force F _N , calculate the _driving force F of each trajectory segment; convert the _driving force F to the current output of the proportional reversing valve 60 or voltage output size, and then respectively control the output pressure of the telescopic rod 310 of the corresponding track segment, the controller 40 executes the program, drives the grinding tool 70 to grind along the grinding track, and in the grinding process, applies a corresponding driving force on each track segment F _drive until the grinding and polishing process is completed. During this process, due to the change of the grinding direction, the gravitational interaction between the F _drive and the floating component results in a grinding force F _N , that is, when the grinding force F _N is constant, the gravity of the F _drive and the floating component are both the driving force, and the F _drive is the driving force. 1. The gravity of the floating component is the resistance or the F _drive is the resistance, and the gravity of the floating component is the driving force. The F _drive can be greater than zero or less than zero (that is, the F _drive and F _N are in the same direction or in the opposite direction).

As shown in Figure 4, Figure 5 and Figure 12, further, combined with the above grinding method with gravity compensation:

(1) As shown in Figure a in Figure 12, when the target inclination angle A is below the horizontal plane, A _< 0°, B<0 _° ; In the same direction as F _N , F _N = F _drive -∣mgsin B∣The range of the grinding force F _N is [0, the maximum value of F _drive -∣mgsin B∣], and the proportional reversing valve is located at the L position.

(2) As shown in Figure b in Figure 12, when the target inclination angle A is on the horizontal plane, A=0°, B=0°; F _drive is the power, the resistance is zero, F _drive and F _N are in the same direction, and the grinding force F _N = F _drive , the proportional reversing valve is located at the L position.

(3) As shown in Figure c and Figure d in Figure 12, when the target inclination angle A is above the horizontal plane, A>0°, B>0°; at this time, the gravity of the floating assembly is the driving force; when the grinding force F When _N ＞∣mgsinB∣, F _drive is in the same direction as F _N , F _N =∣mgsinB∣+F _drive ; when grinding force F _N <∣mgsinB∣, F _drive is opposite to F _N , F _N =∣mgsinB∣ - F _drive , the proportional directional valve is located at the R position.

As shown in Figure 3, Figure 6 and Figure 7, a floating connection mechanism 10 according to the present invention includes: a first connection assembly 100, the first connection assembly 100 includes a first external connection plate 110, and a first external connection plate 110 Opposite the first inner connection disc 120 and at least two guide rods 130 arranged at intervals, the outer side of the first outer connection disc 110 is provided with an outer connection part, one end of all guide rods 130 is fixed with the first outer connection disc 110, and the other end is connected with the first outer connection disc 110. The inner connection plate 120 is fixed; the second connection assembly 200, the second connection assembly 200 can slide relative to the first outer connection plate 110, the second connection assembly 200 includes a movable second inner connection plate 210, a second inner connection plate 210 opposite to the second connection assembly 200 Two outer connecting discs 220, and at least two connecting rods 230 arranged at intervals, the second inner connecting disc 210 is arranged between the first outer connecting disc 110 and the first inner connecting disc 120, and is slidably connected with all guide rods 130, and all connecting rods 230 One end is fixed to the second inner connecting disc 210, the other end is fixed to the second outer connecting disc 220, and the second outer connecting disc 220 is provided with a connecting portion 204; and the first telescopic device 300 is fixed to the first outer connecting disc. 110 , and the first telescopic device 300 is provided with a telescopic rod 310 that can float and adjust the output pressure, and one end of the telescopic rod 310 is fixedly connected with the second inner connection plate 210 .

As shown in Fig. 2, Fig. 3, Fig. 5, Fig. 6 and Fig. 7, when the above-mentioned floating connection mechanism 10 is in use, the first external connection plate 110 is fixedly connected with the operating head 20 of the robot through the external connection portion, and the second external connection plate 220 is installed and fixed with the grinding tool 70 through the connecting part 204; when using the robot to connect the grinding tool 70 for grinding work, the grinding head 72 of the grinding tool 70 is in flexible contact with the workpiece 90 to be polished. When encountering a large flash burr, The telescopic rod 310 can shrink according to the preset output pressure when the extrusion force increases, so that the contact force between the grinding head 72 and the workpiece 90 to be polished can adapt to the change of the workpiece surface; when encountering a small flash When there is a burr, the telescopic rod 310 can be stretched according to the preset output pressure when the extrusion force is reduced, so that the contact force between the grinding head 72 and the workpiece 90 to be polished can adapt to the change of the surface of the workpiece, so that in the grinding process The running speed of the middle grinding head 72 is uniform, and the grinding and polishing quality of the workpiece 90 to be ground is good, and the stability is high. The floating connection mechanism 10 allows a certain degree of misalignment between the grinding tool 70 and the workpiece 90 to be polished, which can avoid rigid collision between the grinding tool 70 and the workpiece 90 to be polished, and at the same time, the normal polishing of the grinding head on the surface The force can be precisely controlled following changes in the curvature of the curved surface, thereby improving the stability of the grinding quality and yield of the polished workpiece 90 .

As shown in FIG. 6 and FIG. 7 , in this embodiment, the first inner connection plate 120 is provided with a matching through hole 122 that is slidably fitted with the connecting rod 230 . Therefore, the sliding fit between the first inner connecting disc 120 and the connecting rod 230 can further improve the stability of the second outer connecting disc 220 during the reciprocating movement, making the grinding head 72 more stable during the grinding process. Further, there are three guide rods 130 , and the three guide rods 130 are evenly spaced between the first outer disc 110 and the first inner disc 120 . Therefore, the three guide rods 130 transmission mode is used to make the second connecting assembly 200 move with high rigidity and strong overall stability, avoiding the trembling of the robot end when moving, and further improving the grinding and polishing quality of the workpiece 90 to be ground. Still further, the second inner connecting disc 210 slides and fits with the guide rod 130 through the linear ball bearing 212, which further makes the movement of the second inner connecting disc 210 more stable and the force transmission more accurate.

In the above embodiment, the first telescopic device 300 is a hydraulic cylinder, and the telescopic rod 310 is a hydraulic telescopic rod 310; or the first telescopic device 300 is a pneumatic cylinder, and the telescopic rod 310 is a pneumatic telescopic rod 310; Pneumatic drive, the whole process is more stable.

As shown in FIG. 3 , FIG. 6 , and FIG. 7 , in the above embodiments, the connecting rod 230 and the guide rod 130 are staggered. Therefore, the connection and cooperation between the first connection assembly 100 and the second connection assembly 200 can be made more compact, and it is convenient to put the dust jacket 600 on.

As shown in Fig. 3 and Fig. 6 to Fig. 11, in the above-mentioned embodiment, the second external connection plate 220 is provided with the installation body 224 that protrudes outwards and is arranged on the outside of the second external connection disk 220 and cooperates with the installation body 224 to form The mounting structure 240 of the connecting portion 204, the mounting body 224 is provided with a matching hole 202, the mounting structure 240 includes a locking member 242 that can be elastically reset and penetrates the side wall of the matching hole 202, and a locking member 242 fixed on the outside of the second external connection plate 220 Positioner 244 . Therefore, it can be positioned by the positioning member 244 and then locked by the locking member 242 to realize quick disassembly and assembly of the second external disc 220 and the grinding tool 70 and improve the installation efficiency of the grinding tool 70 . Specifically, it also includes a connecting piece 500, the connecting piece 500 is provided with a connecting hole 510 fitted with the installation body 224, a matching groove 520 tightly fitted with the locking piece 242, and a positioning hole matched with the positioning piece 244 530 , the matching groove 520 is disposed on the inner side wall of the connecting hole 510 , and the second external connection plate 220 is fixedly connected to the grinding tool 70 through the connecting piece 500 . Therefore, during installation, the positioning hole 530 of the connecting piece 500 is positioned and matched with the positioning piece 244 of the second external connection plate 220, and the connecting hole 510 is matched with the mounting body 224. At this time, the telescopic length of the locking piece 242 is adjusted so that the locking piece 242 Form a locking fit with the matching groove 520, and then install and fix the connecting piece 500 and the second external connection plate 220; when it needs to be disassembled, only need to adjust the output pressure of the locking piece 242, so that the locking piece 242 exits the matching groove 520 , the connection member 500 can be separated from the second external connection plate 220 . Further, it also includes a second telescopic device 400 for controlling the expansion and contraction of the locking member 242. The second telescopic device 400 includes a cone 410 that can telescopically move in the matching hole 202. The large end of the cone 410 is set close to the second inner connection plate 210. , and the big end of the cone 410 is press-fitted with one end of the locking member 242 . Thereby can adjust the position of the cone 410 by the second telescopic device 400 and can realize the expansion and contraction of the locking member 242; When the big end of the cone 410 is pressed against one end of the locking piece 242, one end of the locking piece 242 shrinks, and the other end protrudes and is arranged outside the matching hole 202 On the wall, it can form a locking fit with the wall of the fitting groove 520 of the connector 500 . Still further, the first inner connection plate 120 is provided with a dislocation through hole 124 in a hollow ring shape, which facilitates the installation of the fourth telescopic device 400 and reduces the movement interference of the fourth telescopic device 400 to the second connecting assembly.

It should be noted that the second telescopic device 400 is a hydraulic cylinder or a pneumatic cylinder; preferably, the first telescopic device 300 and the second telescopic device 400 all adopt double-acting single-rod pneumatic cylinders, and can share the power device 50 (the power device is The air source device, the air source device includes a manual drainage filter, a manually adjustable overflow pressure regulator, a pressure gauge and a lubricator), and is driven by pneumatics, so that the whole process is more stable, and its specific implementation method can be used in the prior art Realized, no more cumbersome here.

Beneficial effects of the present invention:

1. Offline programming realizes the pose and pose control of the robot, while the head of the force control device adopts air pressure proportional servo control to realize force control alone, avoiding cumbersome force-position coupling control. Simultaneously, this independent force application mechanism (floating connection mechanism 10) can ensure the quick response of output force;

2. The floating connection mechanism 10 makes the flexible contact between the tool and the workpiece improved when the robot grinds the workpiece 90, allowing a certain degree of dislocation between the polishing tool and the workpiece, and avoiding the rigid collision between the grinding tool 70 and the workpiece, so that the grinding tool 70 is in the The surface of the workpiece runs well, improves the stability of the grinding quality, improves the service efficiency and life of the grinding tool 70 , and improves the yield of the grinding workpiece 90 .

3. It can avoid the phenomenon that the speed of the pneumatic grinding and polishing tool is obviously reduced due to insufficient power when the contact pressure between the grinding and polishing disc and the workpiece is high, and the running speed of the grinding head 72 of the grinding tool 70 is relatively stable.

4. The arrangement of three guide rods 130 is adopted, which has high rigidity and strong overall stability, and avoids shaking when the end of the robot moves.

The technical features of the above-mentioned embodiments can be combined arbitrarily. To make the description concise, all possible combinations of the technical features in the above-mentioned embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, should be considered as within the scope of this specification.

The above-mentioned embodiments only express several implementation modes of the present invention, and the descriptions thereof are relatively specific and detailed, but should not be construed as limiting the patent scope of the invention. It should be pointed out that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be based on the appended claims.

Claims (10)

1. A grinding robot with gravity compensation, characterized in that it includes a floating connection mechanism, and also includes a movable operating head, an inclination sensor and a controller; The floating connection mechanism includes a first connection assembly, and the first connection assembly includes a first outer connecting plate, a first inner connecting plate opposite to the first outer connecting plate, and at least two guide rods arranged at intervals. An external connection part is provided on the outside of an external connection plate, and one end of all the guide rods is fixed to the first external connection plate, and the other end is fixed to the first internal connection plate; the second connection assembly, the second connection assembly can be opposite Sliding on the first outer connection plate, the second connection component includes a movable second inner connection plate, a second outer connection plate opposite to the second inner connection plate, and at least two connecting rods arranged at intervals, the second The inner connecting disc is arranged between the first outer connecting disc and the first inner connecting disc, and is slidably connected with all the guide rods, one end of all the connecting rods is fixed to the second inner connecting disc, and the other end is connected to the second inner connecting disc. The second external disk is fixed, and the second external disk is provided with a connecting portion; and the first telescopic device is fixed on the first external disk, and the first telescopic device is provided with A telescopic rod that can float to adjust the output pressure, one end of the telescopic rod is fixedly connected to the second inner connection plate; The operation head is fixedly connected to the external connection part, the inclination sensor is installed on the first external connection plate, the controller can control the operation head to move according to the preset grinding track, and the controller can obtain The inclination data detected by the inclination sensor and the output pressure of the expansion rod of the first expansion device are controlled. 2. The grinding robot with gravity compensation according to claim 1, characterized in that, the second external disc is provided with a mounting body that protrudes outward and is arranged on the outside of the second external disc and is connected with the mounting body. bodies cooperate with each other to form the mounting structure of the connecting part, the mounting body is provided with a matching hole, the mounting structure includes a locking piece that can be elastically reset and penetrates the side wall of the matching hole, and is fixed on the The positioning part on the outer side of the second circumscribed disk. 3. The grinding robot with gravity compensation according to claim 2, further comprising a second telescopic device for controlling the expansion and contraction of the locking member, the second telescopic device includes a As for the moving cone, the big end of the cone is arranged close to the second inscribed disc, and the big end of the cone is press-fitted with one end of the locking member. 4. A grinding method with gravity compensation applied to a grinding robot with gravity compensation according to any one of claims 1 to 3, characterized in that it comprises the following steps: According to the planned grinding trajectory, the preset multiple target points are P ₁ , P ₂ ... P _n and the multi-segment trajectory segments are P ₁ -P ₂ , P ₂ -P ₃ ... P _n-1 -P _n , Obtain the target inclination angle A of each target point; According to the target inclination A of each target point, calculate the preset inclination B of each track segment; Obtaining the mass m of the preset floating component, and combining the preset inclination B of each track segment and the preset grinding force F _N , calculating the _driving force F of each track segment; Grinding along the grinding track, during the grinding process, applying a corresponding _driving force F on each track segment; Wherein, the target inclination A is the angle between F _N and the horizontal plane, and -90°≤A≤90°, the target inclination A is positive when it is above the horizontal plane, the target inclination A and the horizontal plane coincide to be zero, and the target inclination A is at Below the horizontal plane is negative; the trajectory segment is the trajectory line between two adjacent target points, n is a positive integer, and n≥4; F _N is the normal positive pressure of the grinding head on the workpiece surface, when When F _drive and F _N are in the same direction, F _drive = F _N -mgsin B, when F _drive and F _N are in the opposite direction, F _drive = |mgsin B|-F _N . 5. The grinding method with gravity compensation according to claim 4, wherein the preset inclination angle B of the trajectory segment is equal to the average of the sum of the target inclination angles A of the corresponding two adjacent target points value. 6. The grinding method with gravity compensation according to claim 5, wherein when grinding is performed on one of the trajectory segments P _i -P _i+1 , the corresponding two target points are P _i and P _i+1 , the target inclination angle of the target point P _i is A _i , and the target inclination angle of the target point P _i+1 is A _i+1 ; When F _drive and F _N are in the same direction, the driving force F _drive corresponding to the trajectory segment P _i -P _i+1 = F _N -mgsin B = F _N -mgsin[(A _i +A _i+1 )/2 ]; when F _drive and F _N reverse, F _drive = |mgsin B|-F _N = |mgsin[(A _i +A _i+1 )/2]|-F _N ; where, i is a positive integer. 7. The grinding method with gravity compensation according to claim 4, further comprising planning the grinding trajectory according to the surface curvature change of the workpiece to be ground. 8. The grinding method with gravity compensation according to claim 4, characterized in that, when the surface curvature of the grinding workpiece between two adjacent said target points changes greatly, the corresponding two adjacent said targets The length of the trajectory line between the points is smaller. 9. The grinding method with gravity compensation according to any one of claims 4 to 8, characterized in that the change in the size of the _driving force F is obtained by adjusting the direction, voltage or current of the proportional reversing valve. 10. The grinding method with gravity compensation according to claim 9, characterized in that, the required _driving force F for all trajectory segments corresponds to the direction, current I or voltage U of one proportional reversing valve respectively.