A mechanical arm for furniture board cloth glue

Abstract

The present invention relates to a manipulator for applying glue to furniture boards, and belongs to the field of manipulators. The manipulator for applying glue to furniture boards described in the present invention comprises a manipulator arm, a clamping claw is installed at the front end of the manipulator arm, and the clamping claw comprises a base, a claw body, a clamping claw driving mechanism for driving all the clamping claws to clamp or release, and a vibration mechanism for applying vibration to the furniture board clamped by the clamping claw. The present invention optimizes and improves the structure of the existing clamping claws, and its clamping action is more suitable for clamping furniture boards. The manipulator arm is flexible in action and has a high degree of freedom, and is more suitable for applying glue to furniture boards. By setting a vibration mechanism for applying vibration to the furniture board clamped by the clamping claw, not only can the glue dipping effect be improved, but also the vibration can be used to shake off the glue, which effectively solves the problem of excessive glue overflow at the edge, reduces the burden of subsequent glue scraping, ensures the quality of furniture board splicing, and improves work efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of manipulators, in particular to a manipulator for gluing furniture board cloth. Background Art

[0002] In the field of furniture processing, it is usually necessary to apply glue and glue to various types of furniture boards, such as spliced ​​boards, multi-layer stacked boards, etc., especially some boards with special structures, which need to rely more on manual labor. Using a robot to apply glue cannot be done accurately. For example, when using furniture boards for gluing, the side of the furniture board that needs to be glued is sent into the glue tank for dipping. Since wood glue usually has high viscosity, it needs to be scraped after dipping. If this step relies solely on the mechanized operation of the robot, there will often be excessive glue overflow on the edges of local areas (due to differences in viscosity, strength, gravity, etc., the wood glue on the board surface is unevenly distributed). Excessive overflow of wood glue will increase the burden of subsequent scraping of glue, and may even affect the appearance of the furniture board. For furniture boards that affect the appearance, workers usually need to rely on experience to further trim and modify them in the future, which greatly affects work efficiency.

[0003] Based on this, the present invention is proposed. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention provides a mechanical arm for gluing furniture panels, and the technical solution is as follows:

[0005] A robot for applying glue to furniture panels comprises a robot arm, a clamping jaw is installed at the front end of the robot arm, the clamping jaw comprises a base, a plurality of clamping jaws slidably connected to the base, a clamping jaw driving mechanism for driving all the clamping jaws to clamp or release, a vibration mechanism for applying vibration to the furniture panel clamped by the clamping jaws, and a hollow connecting portion connected to the front end of the robot arm, a driven bar mounting portion is arranged at the bottom of the clamping jaw, the clamping jaw driving mechanism comprises a power bar, a center disk embedded in the middle section of the power bar, driven bars corresponding to the driven bar mounting portion one by one, and a stepping motor for driving the center disk to rotate, the center disk is rotatably connected to the base, the head end of the driven bar is hinged to the driven bar mounting portion, and the tail end of the driven bar is rotatably connected to the end of the power bar; the hollow connecting portion is fixedly connected to the base.

[0006] As a further solution of the present invention, the vibration mechanism includes a vibration conversion box and a vibration motor. The vibration conversion box includes a box body. The top of the box body is provided with a vibration motor mounting groove compatible with the vibration motor. The top of the box body is fixedly connected to the base. The bottom of the box body is wrapped with a reinforced rubber sleeve. The sleeve opening of the reinforced rubber sleeve is sealed and connected to the bottom of the box body. The bottom of the reinforced rubber sleeve is provided with a wavy surface with a wavy cross-section. The wavy surface is inclined. A non-Newtonian fluid containing cavity is formed between the reinforced rubber sleeve and the box body. The non-Newtonian fluid containing cavity is filled with a non-Newtonian fluid.

[0007] As a further solution of the present invention, two claw bodies are provided.

[0008] As a further solution of the present invention, the base is provided with a slide groove, and the central projection of the central disk is arranged colinearly with the central axis of the slide groove; and a sliding block adapted to the slide groove is arranged at the bottom of the driven bar mounting portion.

[0009] As a further solution of the present invention, a thickened portion is installed on the inner side of the claw body, an arc-shaped groove is provided on the outer side of the thickened portion, and an arc-shaped gasket is connected to the arc-shaped groove.

[0010] As a further solution of the present invention, the slide groove is a dovetail groove or a T-shaped groove.

[0011] As a further solution of the present invention, the rotor speed in the vibration motor is controlled by a frequency converter;

[0012] When the robotic arm clamps the furniture board through the clamping claws, the furniture board contacts the reinforced rubber sleeve;

[0013] When the furniture board is being glued, the speed of the vibration motor is n s , n s It changes periodically; in one cycle, n s It changes in four stages;

[0014] n s The speed in the first stage is n1, 0≤n1≤300r / min, and the time of the first stage is t1, t1=3s;

[0015] n s The speed in the second stage is n2, 300≤n2≤1500r / min, the time of the second stage is t2, t2=15s, and the cumulative time of n2 in the speed range of 1380~1500r / min is not less than 7s;

[0016] n sThe speed in the third stage is n3, 540≤n3≤1500r / min, the time of the third stage is t3, t3=10s, and the cumulative time of n3 in the speed range of 540~780r / min is not less than 6s;

[0017] n s The speed in the fourth stage is n4, 0≤n4≤540r / min, and the time of the fourth stage is t4, t4=2s;

[0018] T is a cycle, T=t1+t2+t3+t4, t z =λ·T, λ is a positive integer, t z It is the time for applying glue to furniture panels.

[0019] As a further solution of the present invention, the angle between the contact surface between the furniture board and the reinforced rubber sleeve and the trend line of the inclination of the wave surface is β, β=13°.

[0020] As a further solution of the present invention, the non-Newtonian fluid is composed of starch, water and rubber particles mixed in a mass ratio of 5:2:1, the particle size of the rubber particles is 1-1.5 mm, and the density of the rubber particles is less than the density of water.

[0021] As a further solution of the present invention, an open groove for the movement of the clamping claws is provided on the outer side of the vibration conversion box.

[0022] Compared with the prior art, the beneficial effects of the present invention are:

[0023] 1. The furniture board glue manipulator optimizes and improves the structure of the existing clamping claws, and its clamping action is more suitable for clamping furniture boards. The robot arm is flexible in movement and has a high degree of freedom. It is more suitable for carrying furniture boards, machining at various angles, and other operations. It has the advantages of strong load capacity, high precision, strong programmability, high safety and high degree of automation.

[0024] 2. When applying glue to furniture panels, a vibration mechanism is provided to apply vibration to the furniture panels clamped by the clamps, which can not only improve the glue dipping effect, but also use vibration to shake off the glue, effectively solving the problem of excessive glue overflow on the edges, reducing the subsequent burden of scraping glue, ensuring the quality of furniture panel splicing, and improving work efficiency.

[0025] 3. The vibration mechanism is integrated in the gripper, with high integration and does not affect the normal movement of the robot arm. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a schematic diagram of the structure of a mechanical arm for gluing furniture panels and cloth;

[0027] Figure 2is a schematic diagram of the structure of the gripper;

[0028] Figure 3 It is a structural schematic diagram of the gripper driving mechanism;

[0029] Figure 4 It is a structural schematic diagram of a vibration conversion box;

[0030] Figure 5 This is a schematic diagram of the interior of the box;

[0031] Figure 6 This is a test result chart taken during a test to characterize the uniformity of overflow glue. DETAILED DESCRIPTION

[0032] The present invention is described in detail below in conjunction with specific embodiments. The embodiments described below are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention. Example 1

[0033] like Figures 1 to 5 As shown, a furniture board glue robot comprises a robot arm 10, a front end of the robot arm 10 is equipped with a clamping claw 20, the clamping claw 20 comprises a base 21, a plurality of claw bodies 22 slidably connected to the base 21, a clamping claw driving mechanism for driving all the clamping claws 20 to clamp or release, a vibration mechanism for applying vibration to the furniture board clamped by the clamping claws 20, and a hollow connecting portion 25 connected to the front end of the robot arm 10, and a driven strip is arranged at the bottom of the claw body 22. The mounting portion 221, the clamp driving mechanism includes a power bar 32, a center disk 33 embedded in the middle section of the power bar 32, a driven bar 31 corresponding to the driven bar mounting portion 221, and a stepping motor for driving the center disk 33 to rotate, the center disk 33 is rotatably connected to the base 21, the head end of the driven bar 31 is hinged to the driven bar mounting portion 221, and the tail end of the driven bar 31 is rotatably connected to the end of the power bar 32; the hollow connecting portion 25 is fixedly connected to the base 21.

[0034] In this embodiment, two claw bodies 22 are provided.

[0035] The vibration mechanism includes a vibration conversion box 50 and a vibration motor 40. The vibration conversion box 50 includes a box body 51. The top of the box body 51 is provided with a vibration motor mounting groove adapted to the vibration motor 40. The top of the box body 51 is fixedly connected to the base 21. The bottom of the box body 51 is wrapped with a reinforced rubber sleeve 52. The sleeve opening of the reinforced rubber sleeve 52 is sealed and connected to the bottom of the box body 51. The bottom of the reinforced rubber sleeve 52 is provided with a wave surface 511 with a wave-shaped cross-section. The wave surface 511 is inclined. A non-Newtonian fluid containing cavity 53 is formed between the reinforced rubber sleeve 52 and the box body 51. The non-Newtonian fluid containing cavity 53 is filled with a non-Newtonian fluid.

[0036] The rotor speed in the vibration motor 40 is controlled by a frequency converter;

[0037] When the robot arm 10 clamps the furniture board through the clamping claw 20, the furniture board contacts the reinforced rubber sleeve 52;

[0038] When the furniture board is being glued, the speed of the vibration motor 40 is n s , n s It changes periodically; in one cycle, n s It changes in four stages;

[0039] n s The speed in the first stage is n1, 0≤n1≤300r / min, and the time of the first stage is t1, t1=3s;

[0040] n s The speed in the second stage is n2, 300≤n2≤1500r / min, the time of the second stage is t2, t2=15s, and the cumulative time of n2 in the speed range of 1380~1500r / min is not less than 7s;

[0041] n s The speed in the third stage is n3, 540≤n3≤1500r / min, the time of the third stage is t3, t3=10s, and the cumulative time of n3 in the speed range of 540~780r / min is not less than 6s;

[0042] n s The speed in the fourth stage is n4, 0≤n4≤540r / min, and the time of the fourth stage is t4, t4=2s;

[0043] T is a cycle, T=t1+t2+t3+t4, t z =λ·T, λ is a positive integer, t z It is the time for applying glue to furniture panels.

[0044] The angle between the contact surface between the furniture board and the reinforced rubber sleeve 52 and the trend line of the inclination of the wave surface 511 is β, β=13°. The trend line refers to the wave line formed by the projection of the wave surface, and its reference line is shown in FIG. Figure 5 The dashed line in .

[0045] The non-Newtonian fluid is composed of starch, water and rubber particles mixed in a mass ratio of 5:2:1, the particle size of the rubber particles is 1-1.5 mm, and the density of the rubber particles is less than the density of water. The rubber particles are preferably EPDM rubber particles with a density of 0.87 g / cm3.

[0046] When the stepper motor drives the center disk 33 to rotate, the two driven bars 31 drive the driven bar mounting portion 221 and the claw body 22 to move toward each other or relative to each other synchronously, so that the clamping claw 20 performs a clamping or releasing action.

[0047] In some embodiments, the reinforced rubber sleeve 52 is reinforced by mixing steel wires into the rubber.

[0048] After the clamping claw 20 clamps the furniture board, the furniture board contacts the vibration conversion box 50. Since the non-Newtonian fluid composed of starch and water exhibits a relatively soft property in the initial state, when the robot arm 10 carries the clamped furniture board into the glue tank for dipping, the robot arm 10 has a high degree of freedom and can be quickly adjusted at different angles, so that furniture boards of different shapes and structures can be dipped in glue in a better posture, ensuring that the dipping surface is in contact with the wood glue to the maximum extent. During the dipping process, the vibration motor 40 is started. Under the vibration transmitted by the vibration motor 40, the non-Newtonian fluid passes through the non-Newtonian fluid containing chamber 53 and is then transmitted to the furniture board, so that the furniture board is dipped in glue within 1 minute (the shortest dipping time). After that, the furniture board that has been dipped in glue is lifted up and leaves the liquid surface of the wood glue. The vibration is continuously vibrated for about 30 seconds (the shortest spinning time) so that the excess glue is thrown off, so that a layer of wood glue with uniform thickness is finally attached to the surface of the furniture board.

[0049] In the present invention, variable frequency control is adopted, and coupled with the special properties of non-Newtonian fluids, it will quickly harden under high-frequency vibrations, so that it can effectively transmit vibrations. Through the above dual means, the vibrations received by the furniture board are multi-frequency vibrations with very complex frequencies, which are more likely to cause vibrations in the wood glue, so that the wood glue can quickly hit the furniture board under the action of resonance, complete a deeper degree of impregnation in a short time, and improve the impregnation effect; therefore, even if most of the excess wood glue is thrown away later, the gluing effect can be guaranteed under squeezing.

[0050] Among them, the power of the vibration motor is 500W, the maximum exciting force is 10KN, and the maximum vibration frequency is 1500r / min. Example 2

[0051] In Example 1, the base 21 is provided with a slide groove 211 , and the central projection of the center disk 33 is arranged colinearly with the central axis of the slide groove 211 ; a slider adapted to the slide groove 211 is arranged at the bottom of the driven bar mounting portion 221 .

[0052] The slide block is slidably connected with the slide groove 211. The slide groove 211 is a dovetail groove or a T-shaped groove. Example 3

[0053] In the first embodiment, a thickened portion 23 is installed on the inner side of the claw body 22 , an arc-shaped groove is provided on the outer side of the thickened portion 23 , and an arc-shaped gasket 24 is connected to the arc-shaped groove.

[0054] The arc-shaped gasket 24 is preferably a rubber gasket, which prevents excessive clamping force from causing clamping marks on the edge of the furniture board. Example 4

[0055] In the first embodiment, in order to prevent interference with the movement of the clamping jaws 20 , an opening groove 501 for the movement of the clamping jaws 20 is provided on the outer side of the vibration conversion box 50 . Comparative Example 1

[0056] The only difference between this example and Example 1 is that no non-Newtonian fluid is provided, the bottom of the box 51 is a plane, which is in direct contact with the furniture board, and the rest are the same. Comparative Example 2

[0057] The only difference between this example and Example 1 is that water is replaced by a non-Newtonian fluid, and the rest is the same. Comparative Example 3

[0058] The difference between this example and Example 1 is that the fine sand is replaced by non-Newtonian fluid, and the rest is the same. Comparative Example 4

[0059] The only difference between this example and Example 1 is that the non-Newtonian fluid in this example is composed of starch and water mixed in a mass ratio of 6:2, and the rest is the same. Comparative Example 5

[0060] The only difference between this example and Example 1 is that the non-Newtonian fluid in this example is composed of starch, water and chloroprene rubber particles mixed in a mass ratio of 5:2:1, and the density of the chloroprene rubber is 1.65 g / cm3; the rest are the same. Comparative Example 6

[0061] The only difference between this example and Example 1 is that when gluing the furniture board, the rotation speed of the vibration motor 40 is accelerated to 1500 r / min within the initial 10 seconds and then maintained at 1500 r / min, and the rest remains unchanged. Comparative Example 7

[0062] The difference between this example and Example 1 is that when the furniture board is being glued,

[0063] n s The speed in the first stage is n1, 0≤n1≤300r / min, and the time of the first stage is t1, t1=3s;

[0064] n s The speed in the second stage is n2, 300≤n2≤780r / min, the time of the second stage is t2, t2=10s, and the cumulative time of n2 in the speed range of 540~780r / min is not less than 7s;

[0065] n s The speed in the third stage is n3, 780≤n3≤1500r / min, the time of the third stage is t3, t3=15s, and the cumulative time of n3 in the speed range of 1380~1500r / min is not less than 6s;

[0066] n s The speed in the fourth stage is n4, 0≤n4≤1380r / min, and the time of the fourth stage is t4, t4=2s;

[0067] The rest remains unchanged.

[0068] 《Impregnation Characterization Test》

[0069] 1. Maximum penetration depth characterization test

[0070] The poplar wood board after being dipped in glue according to the above embodiment or comparative example (such as embodiment 1) was naturally dried, and the thickness of the glue layer after drying was 3mm±0.3mm; the slices were sampled, and the maximum penetration depth was observed and measured by metallographic microscope.

[0071] 2. Glue overflow uniformity characterization test

[0072] For the poplar board impregnated with glue according to the above embodiment (such as embodiment 1), another poplar board is used to butt and squeeze the impregnated poplar board, and the squeezing force is 1 bar. After drying, the width of the glue seam between the two poplar boards is 2mm±0.2mm; the area of ​​the glue block overflowing from the glue seam is calculated by taking pictures and grid method, and the number of abnormal glue blocks is counted. The abnormal glue block refers to a length greater than 5mm or an area greater than 9mm 2 of glue blocks; Figure 6 The arrow in the middle points to an abnormal rubber block, which is longer than 5mm; the distribution density of abnormal rubber blocks = the number of abnormal rubber blocks / the length of the glue seam. The smaller the distribution density of abnormal rubber blocks, the smaller the area of ​​the overflowed rubber blocks and the more evenly distributed they are.

[0073] The above test results are shown in Table 1:

[0074] Table 1

[0075]

[0076] It can be seen from Comparative Example 1 that the bottom of the box body 51 is in direct contact with the furniture board, which is not easy to generate resonance and the penetration depth of the wood glue is very low.

[0077] It can be seen from Comparative Examples 2 and 3 that if water or fine sand is used as filler, complex vibrations cannot be formed and resonance is not easy to occur, resulting in a very low penetration depth of the wood glue.

[0078] From Comparative Examples 4 and 5, it can be seen that starch and water can form a non-Newtonian fluid, which will harden from a soft state (semi-solid) after being subjected to high-frequency vibration, so that it can better transmit vibration, but compared with metal solids, it will absorb part of the vibration, so that the vibration finally transmitted to the furniture board is a vibration with a complex spectrum. However, if starch and water are layered in the initial state, if there is no rubber particle stirring, it will take a period of "preheating", which will affect the shortest dipping time.

[0079] It can be seen from Comparative Examples 6 and 7 that different vibration parameters of the vibration conversion box 50 affect the maximum penetration depth within the same shortest glue dipping time, but have little effect on the uniformity of glue overflow and the shortest glue spinning time. Comparative Example 8

[0080] Compared with Example 1, if the wave surface is replaced by an inclined plane flush with the trend line, it remains unchanged; the main impact is on the uniformity of the overflow glue; the distribution density of abnormal glue blocks is 2.5 pieces / dm, mainly concentrated on the side close to the thick area of ​​the non-Newtonian fluid; the thick area of ​​the non-Newtonian fluid refers to the area where the cross-sectional thickness of the non-Newtonian fluid containing cavity 53 is larger.

[0081] Test Example 1

[0082] In Example 1, if β is 0°, at least three large-area abnormal rubber blocks (the length of the rubber seam is 1 dm) will appear in the area far away from the vibration conversion box 50.

[0083] If β is 10°, 15°, and 45° respectively, the corresponding abnormal rubber block distribution density (the shortest spinning time is 0.5 min) is 1 piece / dm, 1.5 pieces / dm, and 2.5 pieces / dm respectively.

[0084] If β is 90°, in the area far away from the vibration conversion box 50, the corresponding abnormal rubber block distribution density (the shortest glue throwing time is 0.5 min) is greater than 5 pieces / dm, and a large number of dense and uneven overflow glue will appear.

[0085] Taking the wear of the reinforcing rubber sleeve 52 into consideration, β is preferably 13°.

[0086] In addition, it should be understood that those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment may also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A furniture board fabric gluing robot, comprising a robot arm (10), characterized in that: A clamping claw (20) is installed at the front end of the mechanical arm (10), and the clamping claw (20) comprises a base (21), a plurality of claw bodies (22) slidably connected to the base (21), a clamping claw driving mechanism for driving all the clamping claws (20) to clamp or release, a vibration mechanism for applying vibration to the furniture board clamped by the clamping claws (20), and a hollow connecting portion (25) connected to the front end of the mechanical arm (10). A driven bar mounting portion (221) is provided at the bottom of the claw body (22). The clamping claw driving mechanism It comprises a power bar (32), a center disk (33) embedded in the middle section of the power bar (32), a driven bar (31) corresponding to a driven bar mounting portion (221) one by one, and a stepping motor for driving the center disk (33) to rotate, wherein the center disk (33) is rotatably connected to a base (21), the head end of the driven bar (31) is hinged to the driven bar mounting portion (221), and the tail end of the driven bar (31) is rotatably connected to the end of the power bar (32); and the hollow connecting portion (25) is fixedly connected to the base (21); The vibration mechanism comprises a vibration conversion box (50) and a vibration motor (40). The vibration conversion box (50) comprises a box body (51). The top of the box body (51) is provided with a vibration motor mounting groove adapted to the vibration motor (40). The top of the box body (51) is fixedly connected to the base (21). The bottom of the box body (51) is wrapped with a reinforced rubber sleeve (52). The sleeve opening of the reinforced rubber sleeve (52) is sealedly connected to the bottom of the box body (51). The bottom of the reinforced rubber sleeve (52) is provided with a wave surface (511) with a wave-shaped cross section. The wave surface (511) is arranged in an inclined manner. A non-Newtonian fluid containing cavity (53) is formed between the reinforced rubber sleeve (52) and the box body (51). The non-Newtonian fluid containing cavity (53) is filled with a non-Newtonian fluid.

2. A furniture board glue robot according to claim 1, characterized in that: Two claw bodies (22) are provided.

3. A furniture board glue robot according to claim 1, characterized in that: The base (21) is provided with a slide groove (211), and the central projection of the central disk (33) is arranged colinearly with the central axis of the slide groove (211); and a sliding block adapted to the slide groove (211) is arranged at the bottom of the driven bar mounting portion (221).

4. The furniture board glue robot according to claim 1, characterized in that: A thickened portion (23) is installed on the inner side of the claw body (22), an arc-shaped groove is provided on the outer side of the thickened portion (23), and an arc-shaped gasket (24) is connected to the arc-shaped groove.

5. The furniture board glue robot according to claim 3, characterized in that: The slide groove (211) is a dovetail groove or a T-shaped groove.

6. The furniture board glue robot according to claim 1, characterized in that: The rotation speed of the rotor in the vibration motor (40) is controlled by a frequency converter; When the mechanical arm (10) clamps the furniture board through the clamping claw (20), the furniture board contacts the reinforced rubber sleeve (52); When the furniture board is being glued, the rotation speed of the vibration motor (40) is n s , n s It changes periodically; in one cycle, n s It changes in four stages; n s The speed in the first stage is n1, 0≤n1≤300r / min, and the time of the first stage is t1, t1=3s; n s The speed in the second stage is n2, 300≤n2≤1500r / min, the time of the second stage is t2, t2=15s, and the cumulative time of n2 in the speed range of 1380~1500r / min is not less than 7s; n s The speed in the third stage is n3, 540≤n3≤1500r / min, the time of the third stage is t3, t3=10s, and the cumulative time of n3 in the speed range of 540~780r / min is not less than 6s; n s The speed in the fourth stage is n4, 0≤n4≤540r / min, and the time of the fourth stage is t4, t4=2s; T is a cycle, T=t1+t2+t3+t4, t z =λ·T, λ is a positive integer, t z It is the time for applying glue to furniture panels.

7. A furniture board glue robot according to claim 6, characterized in that: The angle between the contact surface between the furniture board and the reinforced rubber sleeve (52) and the trend line of the inclination of the wave surface (511) is β, and β=13°.

8. The furniture board glue robot according to claim 1, characterized in that: The non-Newtonian fluid is composed of starch, water and rubber particles mixed in a mass ratio of 5:2:

1. The particle size of the rubber particles is 1-1.5 mm, and the density of the rubber particles is less than the density of water.

9. The furniture board glue robot according to claim 1, characterized in that: An open slot (501) for the clamping jaw (20) to move is provided on the outer side of the vibration conversion box (50).

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