Power supply device in coating robot

Abstract

The invention relates to a power supply device for supplying power to electrical equipment in a coating robot, comprising a generator (12, 20) for generating power, and a braking device (17, 23, 24) for braking the generator (12, 20) to prevent overspeed operation of the generator (12, 20).

Description

Power supply device in coating robot Technical Field

[0001] This invention relates to a power supply device for supplying power to electrical equipment (such as sensors) in a coating robot (such as a spraying robot). Background Technology

[0002] WO2022 / 157095A1 discloses a painting robot for painting automotive body parts in a painting facility. This known painting robot has multiple electrically powered sensors (such as pressure sensors) within its distal robotic arm (“Arm 2”), and the electrical power required for sensor operation is provided by a generator also located within the distal robotic arm. The generator is mechanically driven by a compressed air turbine supplied with compressed air from the painting facility's compressed air network, with the compressed air pressure maintained at a constant, for example, 6 bar.

[0003] However, during the operation of this spraying equipment, the generator may overspeed, which will result in overvoltage in the generator windings. In the worst-case scenario, these overvoltages can trigger an electric spark with enough energy to ignite the solvent-containing vapors generated during the spraying process. For safety reasons, this situation must be avoided at all costs.

[0004] For a general technical background of this invention, please refer to DE102008020731A1 and DE1488788B. However, both of these documents involve completely different technical fields (wind turbines) or have no connection with the technical field of this invention. Summary of the Invention

[0005] Therefore, the research and development task of this invention is to prevent the generator in the painting robot from generating dangerous electric sparks.

[0006] This research and development task is solved by the power supply device described in the independent claims of this invention.

[0007] Based on the prior art described above, the power supply device of the present invention is designed to supply the electrical energy required for the operation of electrical equipment (such as sensors) in a coating robot (such as a spraying robot).

[0008] Therefore, based on the prior art described above, the power supply device of the present invention is equipped with a generator to generate the electrical energy required for the operation of electrical equipment (such as sensors).

[0009] Compared to the prior art described above, the power supply device of the present invention is characterized by a braking device that brakes the generator to prevent overspeed operation and avoid resulting overvoltage. Therefore, in the power supply device of the present invention, the rotation of the generator is no longer entirely dependent on the pressure of the compressed air driving it. Instead, the braking device brakes the generator to prevent dangerous overspeed operation.

[0010] In a preferred embodiment of the invention, the braking device for braking the generator includes an eddy current brake. Such eddy current brakes are well known in the prior art and therefore do not require further description.

[0011] Furthermore, according to the prior art described above, the power supply device of the present invention also includes a drive motor for mechanically driving the generator. Preferably, the drive motor is a compressed air turbine having a rotatable turbine disk to which compressed air is blown. The compressed air driving the compressed air turbine can be supplied by the conventional compressed air network of the spraying equipment, as is known in the prior art.

[0012] The aforementioned eddy current brake for braking a generator typically comprises a rotatable brake disc made of conductive material, which rotates together with the generator. At least one magnet is arranged on the brake disc, generating a magnetic field that passes through the disc, thereby inducing eddy currents within the disc during the generator's rotation. These eddy currents generate a braking torque. Preferably, the turbine disk of the compressed air turbine also constitutes the brake disc of the eddy current brake. Therefore, the turbine disk preferably has two functions. On one hand, the turbine disk acts as a mechanical drive component, to which compressed air is blown; on the other hand, the turbine disk also constitutes the brake disc of the eddy current brake.

[0013] The magnet of the aforementioned eddy current brake is preferably arranged axially in front of or behind the brake disc. Alternatively, the magnet may also be arranged radially outside the brake disc, i.e., on the outer periphery of the brake disc.

[0014] In a preferred embodiment of the invention, the braking torque generated by the braking device (such as an eddy current brake) increases as the generator's rotational speed increases. Conversely, the driving torque generated by the drive motor that drives the generator decreases as the generator's rotational speed increases, or is substantially independent of the rotational speed. Therefore, the braking device and the drive motor together constitute a speed regulator that sets the generator's operating speed at a value where the driving torque and braking torque are substantially equal.

[0015] It should be noted that generators, due to their design, have a specific maximum permissible speed, while the regulated operating speed is lower than this maximum. This design ensures that the generator will not exceed the maximum permissible speed during operation, thereby avoiding overvoltage and preventing electrical sparks in the worst-case scenario. The generator's maximum permissible speed is determined by its speed stability or by the generator's maximum permissible output voltage.

[0016] As mentioned earlier, the compressed air driving the compressed air turbine is supplied by a compressed air source, particularly from the conventional compressed air network of the spraying equipment. This compressed air source preferably provides compressed air at a substantially constant pressure, for example, 6 bar. Therefore, when using the power supply device of the present invention, it is not necessary to regulate the pressure of the compressed air supplied for the drive, thus preventing the generator from overspeeding. Conversely, the compressed air for the drive can be at a constant pressure because the braking device of the present invention can prevent overspeeding that could cause disturbances.

[0017] In general, it should be noted that the braking device is preferably designed for wear-free operation, and the eddy current brake is an example of this operating mode.

[0018] The conductive material used for the brake disc of the eddy current brake is preferably metal.

[0019] Furthermore, it should be noted that the electrical device is preferably a sensor, such as a pressure sensor. However, in a preferred embodiment of the invention, multiple electrical devices, such as multiple sensors, may be provided. It should also be noted that the invention is not limited to the type of electrical device; other types of electrical devices can also be used.

[0020] In addition, it should be noted that, generally speaking, the compressed air turbine and the generator are preferably arranged in the same housing, and the two then together constitute a pneumatic generator.

[0021] The generator can be a DC generator or an AC generator.

[0022] It should be noted that the generator preferably outputs low-voltage electricity as its output voltage, which is lower than 1000 volts DC (direct current) or 1500 volts AC (alternating current). Therefore, in the technical solution of this invention, the generator is generally not used to generate high-voltage electricity to electrostatically charge the coating agent.

[0023] Furthermore, it should be noted that the scope of protection of this invention is not limited to the power supply device described above. Instead, the scope of protection also includes coating robots (such as spraying robots) equipped with such a power supply device. The coating robot of this invention typically includes a robot base and multiple movable robot components, such as a proximal robotic arm (“Arm 1”), a distal robotic arm (“Arm 2”), and a multi-axis robot hand. The power supply device described above is preferably arranged within the coating robot, for example, within the distal robotic arm of the coating robot.

[0024] The coating robot of the present invention preferably includes a charging device for charging the coating agent to a high voltage potential, a fact known in the prior art. This device aims to improve coating efficiency and minimize overspraying that causes interference. The coating robot has an electrically grounded area, preferably located within the robot base or the proximal robotic arm of the coating robot. Furthermore, the coating robot preferably has an area that operates at a high voltage potential during operation, particularly located within the distal robotic arm of the coating robot. An insulating device is provided between the high voltage potential area and the electrically grounded area to achieve electrical insulation between the electrically grounded area and the high voltage potential area, and this insulating device is preferably located within the distal robotic arm.

[0025] Electrical equipment (such as sensors) is typically located in an area of ​​high voltage potential within the coating robot, such as inside the remote robotic arm. The generator is also preferably located in this configuration, i.e., preferably also inside the remote robotic arm. The electrical energy required for the operation of the electrical equipment is provided by the generator.

[0026] The compressed air turbine used to drive the generator is preferably also located in an area of ​​the coating robot that is under high voltage, such as within the distal robotic arm of the coating robot. The compressed air driving the compressed air turbine is supplied from the electrically grounded area of ​​the coating robot via a compressed air line, which is preferably made of an electrically insulating material.

[0027] Furthermore, the coating robot of the present invention preferably includes a transmission device for transmitting data (such as measurement data) from electrical equipment (such as pressure sensors) located in a high-voltage potential area of ​​the coating robot to an evaluation device, which is preferably located in an electrically grounded area. The transmission device is connected to the evaluation device via a transmission path, which preferably includes an optical fiber or radio link, to achieve potential isolation between the transmission device in the high-voltage potential area of ​​one side of the coating robot and the evaluation device in the electrically grounded area of ​​the other side of the coating robot.

[0028] Finally, the scope of protection of this invention also includes the use of braking devices (such as eddy current brakes) for braking generators in coating robots (such as spraying robots).

[0029] Other advantageous embodiments of the invention are defined by the dependent claims, or described in more detail below in conjunction with the description of preferred embodiments of the invention and with reference to the accompanying drawings. Attached Figure Description

[0030] Figure 1 shows a perspective view of the painting robot of the present invention; Figure 2 shows a schematic diagram of the painting robot in Figure 1; Figure 3A shows a cross-sectional view of the pneumatic generator of the painting robot in Figures 1 and 2; Figure 3B shows an enlarged cross-sectional view of the eddy current brake region in Figure 3A; Figure 4 shows a schematic diagram of the torque-speed characteristic curve of the pneumatic generator equipped with the eddy current brake. Detailed Implementation

[0031] The following describes an embodiment of the painting robot 1 of the present invention shown in the accompanying drawings. Some of the contents of this embodiment have been disclosed in the prior patent application WO2022 / 157095A1. Therefore, to avoid duplication, reference is made to the prior patent application, the entire contents of which are incorporated herein by reference.

[0032] The structure of the painting robot 1 is a conventional design, which includes a robot base 2, which can be fixedly installed or can move along a walking track not shown.

[0033] A rotatable robot component 3 is mounted on the robot base 2, which can rotate about a vertical axis of rotation.

[0034] The rotatable robot component 3 carries a proximal robotic arm 4 (“Arm 1”), which can swing about a horizontal swing axis.

[0035] The end of the proximal robotic arm 4 is hinged to the distal robotic arm 5 (“Arm 2”).

[0036] The end of the remote robotic arm 5 is attached to a multi-axis robotic hand shaft 6, which guides the cup atomizer 7 with a high degree of mobility.

[0037] The remote robotic arm 5 of the painting robot 1 is equipped with multiple sensors 8-11. These sensors can detect various operating parameters of the painting robot 1, such as forming air pressure, paint pressure, or paint flow rate, which are only examples. The operation of the sensors 8-11 requires electrical energy, which is provided by the pneumatic generator 12 via the combiner device 13. Therefore, the pneumatic generator 12 first transmits electrical energy to the combiner device 13, and then the combiner device 13 provides the electrical energy required for the operation of the sensors 8-11.

[0038] The pneumatic generator 12 is also housed within the remote robotic arm 5.

[0039] An evaluation device 14 is installed inside the proximal robotic arm 4, which is connected to a transmission device in the combiner device 13 via an optical fiber 15. Therefore, the combiner device 13 receives the measured values ​​of various operating parameters of the painting robot 1 from the sensors 8-11 and transmits the measured values ​​to the evaluation device 14 via the optical fiber 15.

[0040] It should be noted that, to improve coating efficiency and avoid overspraying that could cause interference, the paint sprayed by the painting robot 1 is electrostatically charged, a process known in the prior art. This process is achieved by a high-voltage generator (not shown). Due to the electrostatic charging of the paint, the distal robotic arm 5 is essentially under high voltage, while the proximal robotic arm 4, the rotatable robot component 3, and the robot base 2 are all electrically grounded. An insulating device is provided at the proximal end of the distal robotic arm 5 to achieve electrical insulation between the high-voltage area of ​​the painting robot 1 and the electrically grounded area.

[0041] As shown in Figure 3A, the pneumatic generator 12 and the compressed air turbine are housed together in the same housing 16. The housing 16 is equipped with a rotatable turbine disk 17, which has turbine blades 18 distributed along its periphery. During operation, compressed air is blown toward the turbine blades. The compressed air is delivered by the compressed air network of the spraying equipment through the air inlet device 19.

[0042] The turbine disk 17 is mechanically connected to the generator 20, which is used to surround the cooling sleeve 21.

[0043] It should also be noted that the housing 16 of the pneumatic generator 12 is closed by the end cover 22.

[0044] The housing 16 also includes an eddy current brake for braking the turbine disc 17. This eddy current brake comprises multiple bar magnets 23 and 24 arranged beside the turbine disc 17, generating a magnetic field that passes through the turbine disc 17, thereby inducing eddy currents within the conductive turbine disc 17. Therefore, the turbine disc 17 also functions as a brake disc for the eddy current brake.

[0045] The characteristic curves shown in Figure 4 will be described below. It should be noted beforehand that the characteristic curves shown in the figure are merely schematic diagrams, used only to illustrate the control principle of the present invention. In practical applications, the numerical trends of the characteristic curves shown may differ.

[0046] This characteristic curve shows, on the one hand, the driving torque M of the turbine disk 17. DRIVE The trend of variation with rotational speed n; on the other hand, the characteristic curve also shows the braking torque M of the eddy current brake. BRAKE The trend of change with rotational speed n.

[0047] As can be seen from the figure, the braking torque M of the eddy current brake is... BRAKE It increases with increasing rotational speed n, while the driving torque M DRIVE It decreases as the rotational speed n increases. This establishes a stable operating point 25, at which the driving torque M... DRIVE With braking torque M BRAKE They are essentially equal. Therefore, the eddy current brake and the pneumatic generator 12 together constitute a regulator, which sets the generator's rated operating speed n. NENN Set to a constant value, which is lower than the maximum permissible speed n. MAX Exceeding the maximum permissible speed may cause electrical sparks under the worst-case scenario. Therefore, the present invention prevents the pneumatic generator 12 from operating at excessive speeds that could cause interference without regulating the pressure of the compressed air used for driving.

[0048] This invention is not limited to the preferred embodiments described above. Instead, various variations and modifications can be made, all of which utilize the inventive concept of this invention and therefore fall within the protection scope of this invention. In particular, the protection scope of this invention also includes the protected subject matter and technical features of each dependent claim, which are independent of the claims they refer to, and in particular, may exist independently of the technical features of the independent claims. Therefore, this invention comprises multiple inventive aspects that are independently protected.

[0049] The beneficial effects of this invention: The braking device (such as an eddy current brake) of this invention can advantageously prevent dangerous overspeed operation of the generator used for power supply, while avoiding the resulting overvoltage. This design can reliably prevent electrical sparks from igniting solvent-containing vapors in the spraying equipment.

[0050] A particular advantage of this invention is that it eliminates the need for regulation of the compressed air driving the pneumatic generator. Instead, the pneumatic generator can be supplied with compressed air at a constant pressure, such as 6 bar, from the conventional compressed air network of the spraying equipment.

[0051] In addition, another advantage of the present invention is that the eddy current brake used operates without wear, has low manufacturing cost, and does not require any mechanical components to be arranged on the rotor and stator.

[0052] List of reference numerals: 1. Spraying robot; 2. Robot base of the spraying robot; 3. Rotatable robot component of the spraying robot; 4. Proximal manipulator of the spraying robot; 5. Remote manipulator of the spraying robot; 6. Robot hand shaft; 7. Rotary cup atomizer; 8-11. Sensors inside the remote manipulator; 12. Pneumatic generator inside the remote manipulator; 13. Combining device inside the remote manipulator; 14. Evaluation device inside the proximal manipulator; 15. Optical fiber; 16. Housing of the pneumatic generator; 17. Turbine wheel for driving the generator in the pneumatic generator; 18. Turbine blades of the turbine wheel; 19. Air inlet device of the pneumatic generator; 20. Generator in the pneumatic generator; 21. Cooling sleeve; 22. End cap of the housing; 23, 24. Bar magnet of the eddy current brake; 25. Operating point M and torque M of the pneumatic generator. DRIVE The driving torque M of the pneumatic turbine BRAKE The braking torque N of the eddy current brake and the rotational speed n MAX Maximum permissible speed n NENN Operating speed

Claims

1. A power supply device for supplying electrical energy to electrical equipment in a coating robot (1), particularly a spraying robot (1) for spraying paint on vehicle body parts, comprising: a) A generator (12, 20) for generating electricity, characterized in that the power supply device further includes: b) a braking device (17, 23, 24) for braking the generator (12, 20) to prevent the generator (12, 20) from overspeeding.

2. The power supply device according to claim 1, characterized in that, The braking devices (17, 23, 24) include eddy current brakes (17, 23, 24).

3. The power supply device according to any one of the preceding claims, characterized in that, The power supply device also includes drive motors (17, 18, 19) for mechanically driving the generators (12, 20).

4. The power supply device according to claim 3, characterized in that, The drive motor (17, 18, 19) is a compressed air turbine with a rotatable turbine disk (17) to which compressed air is blown.

5. The power supply device according to claim 4, characterized in that, a) The eddy current brake (17, 23, 24) includes a brake disc (17) that rotates with the generator (12, 20) and is made of a conductive material; and b) At least one magnet (23, 24) is arranged on the brake disc (17) that generates a magnetic field through the brake disc, thereby inducing eddy currents in the brake disc (17) during the rotational motion of the generator (12, 20); and c) The turbine disk (17) of the compressed air turbine constitutes the brake disc (17) of the eddy current brake (17, 23, 24); d) The magnet (23, 24) is preferably arranged axially in front of the brake disc (17), or axially behind the brake disc (17), or radially outside the brake disc (17).

6. The power supply device according to any one of claims 3 to 5, characterized in that, a) The braking torque (M) generated by the braking devices (17, 23, 24) BRAKE The torque (m) increases with the rotational speed (n) of the generators (12, 20); and / or b) the driving torque (M) generated by the drive motors (17, 18, 19) increases with the rotational speed (n) of the generators (12, 20); DRIVE The speed regulation (c) decreases as the rotational speed (n) of the generator (12, 20) increases, or is substantially independent of the rotational speed; and / or the braking device (17, 23, 24) and the drive motor (17, 18, 19) together constitute a speed regulator, which regulates the operating speed (n) of the generator (12, 20). NENN ) set in the driving torque (M DRIVE ) and the braking torque (M BRAKE ) substantially equal values; and / or d) the generators (12, 20) have a permissible maximum speed (n) according to their design structure. MAX ), the adjusted operating speed (n NENN () lower than the maximum speed (n) MAX ); and / or e) the maximum permissible speed (n) MAX The speed stability of the generator (12, 20) or the maximum allowable output voltage of the generator (12, 20) is determined by the speed stability of the generator (12, 20).

7. The power supply device according to any one of claims 4 to 6, characterized in that, a) The compressed air used to drive the compressed air turbines (17-19) is supplied by a compressed air source, particularly by a compressed air network in the spraying equipment; and b) the compressed air source provides compressed air at a substantially constant pressure.

8. The power supply device according to any one of the preceding claims, characterized in that, a) The braking devices (17, 23, 24) are wear-free; and / or b) The conductive material of the brake disc (17) of the eddy current brake (17, 23, 24) is metal; and / or c) The at least one electrical device is a sensor (8-11), particularly a pressure sensor; and / or d) The compressed air turbine (17-19) and the generator (12, 20) are arranged in the same housing (16); and / or e) The generator (12, 20) is a DC generator or an AC generator; and / or f) The output voltage supplied by the generator (12, 20) is low voltage electricity, which is less than 1000 volts DC or 1500 volts AC.

9. A coating robot (1) for applying a coating agent to components, particularly a spraying robot (1) for spraying coatings onto vehicle body components, comprising: a) robot base (2); b) a plurality of movable robot components, particularly: b1) a rotatable robot component (3); b2) a proximal manipulator (4); b3) a distal manipulator (5); and / or b4) a multi-axis robot hand (6); and c) a power supply device according to any one of the preceding claims, wherein the power supply device is arranged within the coating robot (1), particularly within the distal manipulator (5) of the coating robot (1).

10. The coating robot (1) according to claim 9, characterized in that, The coating robot further includes: a) a charging device for electrostatically charging the coating agent to a high voltage potential; b) an electrically grounded area of ​​the coating robot (1), the electrically grounded area being located in particular within the robot base (2), rotatable robot component (3), and / or proximal manipulator (4) of the coating robot (1); c) a region of the coating robot (1) at a high voltage potential during operation, the region of the high voltage potential being located in particular within the distal manipulator (5) of the coating robot (1); and d) an insulating device for achieving electrical insulation between the electrically grounded area of ​​the coating robot (1) and the region at a high voltage potential, the insulating device preferably being arranged within the distal manipulator (5).

11. The coating robot (1) according to claim 10, characterized in that, a) The electrical equipment (8-11) is arranged in the area of ​​the coating robot (1) where it is under high voltage potential, particularly within the remote robotic arm (5); b) The generator (12, 20) is arranged in the area of ​​the coating robot (1) where it is under high voltage potential, particularly within the remote robotic arm (5); and c) The electrical equipment (8-11) is supplied with the electrical energy required for its operation by the generator (12, 20).

12. The coating robot (1) according to claim 11, characterized in that, a) The generators (12, 20) and the compressed air turbines (17-19) are arranged together in the area of ​​the coating robot (1) under high voltage potential, particularly in the remote robotic arm (5) of the coating robot (1); b) Compressed air for driving the compressed air turbines is supplied via compressed air lines; c) The compressed air lines extend from the electrically grounded area of ​​the coating robot (1) to the compressed air turbines in the area of ​​the coating robot (1) under high voltage potential; and d) The compressed air lines are made of electrically insulating material.

13. The coating robot (1) according to any one of claims 9 to 12, characterized in that, The coating robot further includes: a) a transmission device (13) for transmitting data from electrical equipment (8-11) located in a high-voltage area of ​​the coating robot (1), particularly in the distal robotic arm (5) of the coating robot (1); b) an evaluation device (14) for receiving and evaluating the data transmitted by the electrical equipment (8-11), the evaluation device (14) being arranged in the electrically grounded area of ​​the coating robot (1), particularly in the robot base (2), rotatable robot component (3) or proximal robotic arm (4); c) a transmission path (15) connecting the transmission device (13) to the evaluation device (14) to transmit data from the electrical equipment to the evaluation device; d) wherein the transmission path (15) preferably includes an optical fiber (15) or a radio link to achieve potential isolation between the transmission device (13) and the evaluation device (14).

14. Use of a braking device (17, 23, 24), particularly an eddy current brake (17, 23, 24), for braking a generator (12, 20) in a coating robot (1), particularly a spraying robot (1) for spraying automotive body parts.

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