TW202100294A - Grinding machine tool with arbitrary eccentric orbital motion speed detection including a body having a drive shaft and a tool holder connected to a grinding disc - Google Patents

Abstract

A grinding machine tool with arbitrary eccentric orbital motion speed detection is provided. The grinding machine tool includes a body and a grinding disc. The body includes a drive shaft and a tool holder connected to the grinding disc and having an eccentric distance relative to the drive shaft. The grinding disc performs grinding in an arbitrary eccentric orbital motion when the drive shaft rotates. The grinding disc is provided with at least one detected member on the side facing the body for detecting the speed of the arbitrary eccentric orbital motion. The at least one detected member defines a detection area with a range greater than or equal to twice the eccentric distance. In this way, the accurate speed of the grinding disc can be obtained when the arbitrary eccentric orbital motion is performed so that the precision grinding that is gradually automated can control the grinding operation more accurately.

Description

Grinding machine tool with random eccentric orbital speed detection

The invention relates to a grinding machine tool structure, in particular to a grinding machine tool in which a grinding pad defines a detection range for detecting the movement speed of an arbitrary eccentric orbit.

A power tool for grinding or polishing operations is generally called a grinding machine tool in the industry. The driving mode and movement mode of a grinding disc to which the aforementioned grinding machine tool belongs can be mainly divided into three types, which will be explained one by one as follows.

Please refer to FIG. 1. The first driving method is to directly connect a drive shaft 311 of a motor 31 to the grinding disc 30. Because of the direct drive, the rotation per minute (Rotation Per Minute, RPM) of the grinding disc 30 is equal to The rotation speed of the driving shaft 311 only needs to obtain the rotation speed of the driving shaft 311 when the rotation speed of the grinding disc 30 is to be detected. On the other hand, in this driving mode, each point on the grinding disc 30 moves concentrically with respect to the driving shaft 311, and the movement track is shown by the arrow 40 in FIG. 2. Furthermore, this driving method can also be seen in the US patent US 2005/0245183.

Referring to FIG. 3, the second driving method is to mount the grinding disc 30 on an eccentric shaft 32 that is eccentric relative to the drive shaft 311. The eccentric shaft 32 has an eccentric distance 321 relative to the drive shaft 311. The shaft 32 is connected to the drive shaft 311 via a tool holder 33, wherein the tool holder 33 is a bearing. Furthermore, at least one rotation restricting member 34 is further provided between the grinding disc 30 and the drive shaft 311. The rotation restricting member 34 is made of an elastic material. The rotation restricting member 34 restricts the grinding disc 30 from being opposite to each other. The drive shaft 311 moves in an eccentric orbit and cannot perform a free rotation motion (Free Rotation Motion). The motion track of the grinding disc 30 is shown in FIG. 4. Further, any point on the grinding disc 30 performs an eccentric orbital motion relative to the driving shaft 311, and the radius of motion is equal to the eccentric distance 321. In this driving method, the grinding disc 30 is synchronized with the driving shaft 311, that is, the moving speed of the grinding disc 30 is equal to the rotating speed of the driving shaft 311. Therefore, to obtain the Orbital Motions Per Minute (OPM) of the grinding disc 30 only needs to obtain the rotational speed of the drive shaft 311.

Please refer to Figure 5, the third driving method is similar to the second driving method. The difference is that the third driving method does not have the rotation restricting member 34. For related patents, see US patents US6,004,197, US6,979,254, US6,855,040, etc. . The grinding disc 30 does not have a direct linkage relationship with the drive shaft 311. The rotation of the grinding disc 30 is to make the motor 31 rotate to a certain speed. The eccentric shaft 32 generates an inertial centrifugal force to push the grinding The disk 30 rotates. The rotation speed of the grinding disc 30 increases as the rotation speed of the driving shaft 311 increases, but does not exceed the maximum rotation speed of the driving shaft 311. However, when the rotational speed of the driving shaft 311 decreases or stops, the kinetic energy stored in the grinding disc 30 can still drive the grinding disc 30 to continue to rotate until the stored kinetic energy is exhausted. Furthermore, when the grinding disc 30 is driven by inertial centrifugal force to rotate, in addition to performing a rotation motion centered on the eccentric shaft 32, it is also due to the existence of the eccentric shaft 32 and the drive shaft 311 The eccentric distance 321 causes the grinding disc 30 to produce an eccentric orbital motion (Orbital Motion) at the same time. The motion trajectory formed by adding the foregoing two motions is shown in FIG. 4. In addition, the grinding disc 30 actually performs a revolution motion (Revolution Motion) relative to the drive shaft 311 at the same time, and the motion synthesized by the aforementioned three motions is called a random orbital motion (Random Orbital Motion). As shown in Figure 6. Therefore, under this driving structure, the revolving motion and the eccentric orbital motion of the grinding disc 30 are always synchronized with the rotation speed of the driving shaft 311, but because the eccentric shaft 32 is connected to the driving shaft through the tool holder 33 311 is eccentrically assembled, so when the grinding disc 30 contacts the surface of the object to be polished, the rotation speed of the grinding disc 30 will decrease due to the resistance generated by the contact. Furthermore, the shape of the surface of the object to be polished, the angular contact pressure at which the polishing disk 30 contacts the surface of the object to be polished, and the abrasive material used on the polishing disk 30 all produce different resistances, which reduce the rotation of the polishing disk 30. speed. As a result, during the operation, the rotational speed of the rotation of the grinding disc 30 and the eccentric orbital motion are greatly different from the rotational speed of the drive shaft 311, and this difference is constantly changing rapidly during the operation. Therefore, it is very difficult to detect Random Orbital Motions Per Minute (ROPM) of the grinding disc 30 per minute.

Furthermore, although many companies have introduced grinding machine tools with rotation speed detection, in practice, the aforementioned companies regard the rotation speed of the drive shaft 311 as the rotation speed of the grinding disk 30. Once the grinding machine tool is implemented in the aforementioned third drive mode, the true rotation speed of the grinding disc 30 cannot be accurately grasped, which affects the grinding operation. Furthermore, despite the advancement of technology, today's industrial precision grinding has gradually developed towards automation. That is to say, the grinding machine tool will be configured on a robotic arm, but the robotic arm needs to be accurately controlled with precise values. Therefore, the practice of treating the rotational speed of the driving shaft 311 as the rotational speed of the grinding disc 30 will prevent the mechanical arm from being accurately controlled.

The main purpose of the present invention is to solve the problem of the conventional inability to detect the random eccentric orbital speed of the grinding disc.

To achieve the above objective, the present invention provides a grinding machine tool with random eccentric orbital motion speed detection. The grinding machine tool comprises a body and a grinding disc. The body comprises a drive shaft and a drive shaft connected to the grinding disc and opposite to the drive shaft. A tool holder with an eccentric distance, the grinding disc performs grinding with an arbitrary eccentric orbital movement when the drive shaft rotates. Wherein, the grinding disc is provided on the side facing the main body with at least one detected part for detecting the movement speed of the random eccentric orbit, and the at least one detected part defines a detection range greater than or equal to twice the eccentric distance area.

In one embodiment, the grinding disc is provided with a single detected part, and two opposite boundaries of the detection part define a detection area whose range is greater than or equal to twice the eccentric distance.

In one embodiment, the inspected pieces are located on the same extension line, one of the inspected pieces is located at the center of the inspection area, and two of the inspected pieces are located in the center at the eccentric distance. 1. The detected parts are set at intervals.

In one embodiment, the grinding machine tool has an active detection element that faces the grinding disc and does not change its position when the grinding disc performs the random eccentric orbital movement to detect the detected part and output a detection signal. Further, the active detection element is arranged on the side of the main body facing the grinding disc, or the active detection element is externally hung outside the main body by a connecting element.

In one embodiment, the active detection element has an output part that emits a detection wave toward the detected part and a receiving part that receives the detection wave reflected by the detected part and outputs the detection signal, and the detection wave is selected Freedom is one of the group consisting of a light, a radio wave, and a sound wave.

In one embodiment, the active detection element generates the detection signal based on the intensity of the magnetic field changed by the detected element.

In one embodiment, the grinding machine tool has an information processing module which is connected to the active detection component and generates an arbitrary eccentric orbital rotation speed data per minute based on the detection signal. Further, the information processing module includes a waveform processing unit and an arithmetic processing unit connected to the waveform processing unit and analyzing a detection waveform signal output by the waveform processing unit to generate the random eccentric orbital velocity data per minute.

In one embodiment, the active detection element is arranged on the side of the main body facing the grinding disc, and the information processing module is arranged in the main body and connected to the active detection element.

According to the foregoing disclosure, compared with the conventional technology, the present invention has the following characteristics: the present invention uses at least one inspected part provided on the grinding disc to define the inspection area with a range greater than or equal to twice the eccentric distance , The speed at which the grinding disk performs the random eccentric orbital movement can be detected, so that the automation equipment can obtain more accurate control in the fine industrial grinding, and the grinding operation that the automation equipment can perform is increased.

The detailed description and technical content of the present invention are described as follows with the drawings:

Please refer to FIG. 7 and FIG. 8, the present invention provides a grinding machine tool 10, the grinding machine tool 10 can be configured on an automation device (not shown in the figure), and the automation device can be a robotic arm or the like. In addition, the grinding machine tool 10 of the present invention can also be used for polishing operations in addition to polishing operations. The grinding machine tool 10 includes a main body 11 and a grinding disc 12. The main body 11 includes a power assembly 111, a drive shaft 112 driven by the power assembly 111, and a tool holder connected to the grinding disc 12 According to the implementation, the aforementioned power assembly 111 can be pneumatically or electrically implemented. Furthermore, the drive shaft 112 is formed as an eccentric block 114, and the tool holder 113 is disposed on the eccentric block 114 and is eccentric relative to the drive shaft 112. Specifically, the drive shaft 112 has a first axis 115, the tool holder 113 has a second axis 116 deviated from the first axis 115, the first axis 115 and the second axis 116 There is an eccentric distance 117 between. In this way, the grinding disc 12 mounted on the tool holder 113 is eccentric relative to the drive shaft 112. Furthermore, the tool holder 113 can be a single bearing or a combination of multiple bearings. The grinding disc 12 has a mounting member 121 that is assembled with the tool holder 113. The mounting member 121 can be a tool A cylindrical structure in which the holder 113 fits. Accordingly, when the drive shaft 112 rotates, the grinding disc 12 will rotate in a random eccentric orbital motion (Random Orbital Motions).

Please refer to FIGS. 7 and 8 again, the grinding disc 12 is provided with at least one detected part 122 on the side facing the main body 11, and the at least one detected part 122 defines a range greater than or equal to twice the eccentric distance 117 The detection area 123. In view of this, the number of the detected parts 122 of the present invention can be adjusted according to the implementation. As shown in FIG. 8, when the grinding disc 12 is provided with only the inspected part 122, the range of the inspection area 123 is defined by the two sides of the inspected part 122. Please refer to FIG. 9 again. When the grinding disc 12 is provided with a plurality of the detected parts 122, the detection area 123 is defined based on the detected parts 122 located at two opposite edges. Further, when the detected parts 122 are plural, the detected parts 122 may be distributed in the detection area 123 in a regular arrangement. Taking the drawing in FIG. 9 as an example, the inspected parts 122 are located on the same extension line 124, one of the inspected parts 122 is located at the center of the inspection area 123, and two of the inspected parts 122 The eccentric distance 117 is spaced apart from one of the detected parts 122 in the center.

Please refer to FIGS. 7 and 13 again. The grinding machine tool 10 includes an active detection element 118 facing the grinding disc 12 to detect the detected part 122 and output a detection signal 21. Furthermore, the active detection element 118 of the present invention can be configured on a robotic arm, or be hung outside the main body 11 by a connector, or be provided on the side of the main body 11 facing the grinding disc 12 (as shown in FIG. Shown). The active detection element 118 does not change its position when the grinding disc 12 performs the random eccentric orbital movement, that is, the active detection element 118 does not track the detected part 122 during the rotation of the grinding disc 12, and It is waiting for the detected piece 122 to pass by. Furthermore, when the grinding disc 12 is not rotating and the active detection element 118 directly faces the detection area 123, the projection position of the active detection element 118 will be located at the center of the detection area 123. In one embodiment, the distance between the drive shaft 112 and the active detection element 118 is equal to the distance between the mounting element 121 and the center point of the detection area 123. In addition, the active detection element 118 is designed to be positioned on the motion track of the detection area 123, so that every time the grinding disc 12 rotates one revolution relative to the main body 11, the detected element 122 can be detected by the active detection element. 118 was detected once. 10 and FIG. 11, when the grinding disc 12 is provided with a plurality of the detected parts 122, the grinding disc 12 keeps changing its position during the random eccentric orbital movement, and the active detection part 118 does not always detect the same detected part 122, but randomly senses one of the detected parts 122 based on the current state of the grinding disc 12.

Please also refer to FIG. 14. In one embodiment, the active detection element 118 has an output portion 119 that emits a detection wave 20 toward the detected element 122, and an output portion 119 that receives the detection wave 20 reflected by the detected element 122 and outputs The receiving part 110 of the detection signal 21. Wherein, the detection wave 20 is one selected from the group consisting of a light, a radio wave, and a sound wave.

In addition, the description is made when the detection wave 20 is the light. In this embodiment, the at least one detected component 122 is a reflective component, and the active detection component 118 is an optical transceiver component. Further, the detection wave 20 can be infrared or laser. During implementation, the active detection element 118 is controlled to project the light toward the grinding disc 12, and the grinding disc 12 rotates until the detection area 123 faces the active detection element 118, the detected element 122 in the detection area 123 By reflecting the light, the active detection element 118 can receive the reflected light and output the detection signal 21. In view of this, this embodiment can be applied to a place where there is no strong interference with the light source in the grinding operation environment. On the other hand, the detection wave 20 is used as the radio wave for description. First, the radio wave can be referred to as a radio frequency. Therefore, in this embodiment, the detected component 122 and the active detection component 118 can be used for radio frequency identification (Radio Frequency Identification). Identification) architecture implementation. Further, the detected component 122 is a radio frequency tag, and the active detection component 118 is a radio frequency reader. In implementation, the active detection element 118 can be set to send a radio frequency signal to the grinding disc 12 for a long time. When the detected element 122 of the radio frequency tag enters the reading range of the active detection element 118, the The active detection component 118 finishes reading and outputs the detection signal 21. In addition, this embodiment can be applied to places where there is no strong interference with electric waves during polishing operations. Furthermore, when the detection wave 20 is the sound wave for description, the detected part 122 may be a structure that causes the surface of the grinding disc 12 to be uneven, or an object with different acoustic impedance from the grinding disc 12, and the active detection part 118 is a sound wave detector. During implementation, the active detection element 118 emits the sound wave to the grinding disc 12 for a long time. The sound wave will generate different reflected waves due to the different surface conditions of the grinding disc 12 or the parts of the grinding disc 12 with different acoustic impedances. The active detection element 118 generates different signals based on the aforementioned reflected waves, and outputs the detection signal 21.

In addition to the foregoing, the active detection element 118 of the present invention can also generate the detection signal 21 based on the intensity of the magnetic field changed by the detected element 122. For example, the detected component 122 is a magnet, and the active detection component 118 is a Hall detection component. In implementation, when the detected component 122 passes the active detecting component 118, the detected component 122 of the magnet makes the active detecting component 118 detect the increased magnetic field strength, and the active detecting component 118 converts the magnetic signal into an electrical signal according to this. , Output the detection signal 21. In view of this, this embodiment can be applied to polishing operations where the polishing object is a non-metallic material. In addition to the foregoing, the detected component 122 and the active detection component 118 can also be implemented in a Proximitw Switch structure. Specifically, the detected element 122 is an iron sheet, and the active detection element 118 is composed of an excitation coil and a magnetic field change signal detection unit. During implementation, the excitation coil is energized to establish a magnetic field, and the detected component 122 will cause magnetic loss when passing through the aforementioned magnetic field. The magnetic field change signal detection unit generates different detection signals 21 due to the impedance change derived from the aforementioned magnetic loss. The detection signal 21 is different to obtain the rotation speed of the random eccentric orbital motion. Moreover, this embodiment can be applied to places where there is no interference from other high-frequency signals in the grinding environment.

Please refer to FIG. 13 again. The grinding machine tool 10 may further have an information processing module 13 connected to the active detection component 118 and generating data of the rotation speed of the eccentric orbital movement per minute based on the detection signal 21. The information processing module 13 It can be set on the robotic arm or in a control device for managing the work of the robotic arm. In addition, in the embodiment in which the active detection element 118 is provided in the main body 11, the information processing module 13 can also be assembled in the main body 11. Furthermore, in an embodiment, the information processing module 13 can be designed to have the ability to control the opening and closing of the active detection element 118. In addition, the information processing module 13 can be connected to an external electronic device via a wired or wireless manner to transmit the data of the random eccentric orbital speed per minute to the external electronic device, so that the external electronic device can be based on the random per minute The rotational speed data of the eccentric orbital motion performs relative work management. In one embodiment, the external electronic device may be the aforementioned control device. Please refer to FIG. 13, in one embodiment, the information processing module 13 may include a waveform processing unit 131 and an arithmetic processing unit 132 connected to the waveform processing unit 131. The main function of the waveform processing unit 131 is to detect the active The detection signal 21 output by the component 118 performs noise filtering, and outputs a detection waveform signal 133 to the arithmetic processing unit 132. Further, the waveform processing unit 131 may be a digital filter. After the arithmetic processing unit 132 receives the detection waveform signal 133, the arithmetic processing unit 132 generates the random eccentric orbital rotation speed data per minute based on a pre-written program calculation. Accordingly, the information processing module 13 can be realized by a plurality of electronic components that generate electrical connections.

Therefore, the present invention provides a technical means for detecting the speed of the random eccentric orbital movement of the grinding disc 12, which solves the problem that the conventional method cannot be detected but can only be estimated at the rotational speed of the drive shaft 112, which leads to automated equipment for fine industrial grinding. Problems that cannot be precisely controlled.

In summary, it is only a preferred embodiment of the present invention. When the scope of implementation of the present invention cannot be limited by this, that is, all equal changes and modifications made according to the scope of the patent application of the present invention shall still belong to the present invention. The scope of patent coverage.

10: Grinding machine tool 11: body 111: Power Components 112: drive shaft 113: Tool holder 114: eccentric block 115: first axis 116: second axis 117: eccentric distance 118: Active detection parts 119: Output Department 110: receiving department 12: Grinding disc 121: installation parts 122: detected parts 123: detection area 124: Extension line 13: Information Processing Module 131: Waveform processing unit 132: Operation processing unit 133: Detect waveform signal 20: Detection wave 21: Detection signal 30: Grinding disc 31: Motor 311: drive shaft 32: eccentric shaft 321: eccentric distance 33: Tool holder 34: Rotation restriction 40: Arrow

Fig. 1 is a schematic diagram of the first type of driving structure of a conventional grinding tool. Fig. 2 is a schematic diagram of the movement track of the grinding disc of the first type of driving structure of the conventional grinding tool. Fig. 3 is a schematic diagram of the second type of driving structure of the conventional grinding tool. Fig. 4 is a schematic diagram of the movement track of the grinding disc of the second type of driving structure of the conventional grinding tool. Fig. 5 is a schematic diagram of a third type of driving structure of a conventional grinding tool. Fig. 6 is a schematic diagram of the movement track of the grinding disc of the third type of driving structure of the conventional grinding tool. Fig. 7 is a schematic diagram of the structure of the grinding machine tool of the present invention (1). Fig. 8 is a schematic top view of the structure of the grinding disc of the present invention (1). Figure 9 is a schematic top view of the structure of the grinding disc of the present invention (2). Fig. 10 is a schematic diagram of the structure of the grinding machine tool of the present invention (2). Figure 11 is a schematic diagram of the operation of the grinding disc of the present invention (1). Figure 12 is a schematic diagram of the operation of the grinding disc of the present invention (2). Fig. 13 is a schematic diagram of the unit of the grinding machine tool of the present invention (1). Figure 14 is a schematic diagram of the unit of the grinding machine tool of the present invention (2).

112: drive shaft

113: Tool holder

114: eccentric block

117: eccentric distance

12: Grinding disc

121: installation parts

122: detected parts

123: detection area

Claims (18)

A grinding machine tool with random eccentric orbital speed detection. The grinding machine tool comprises a main body and a grinding disc. The main body comprises a drive shaft and a tool holder connected to the grinding disc and having an eccentric distance relative to the drive shaft , The grinding disc performs grinding with an arbitrary eccentric orbital motion when the drive shaft rotates, and the grinding machine tool is characterized by: The grinding disc is provided with at least one detected part for detecting the speed of the random eccentric orbital movement on the side facing the main body, and the at least one detected part defines a detection area with a range greater than or equal to twice the eccentric distance . The grinding machine tool with random eccentric orbital movement speed detection according to claim 1, wherein the grinding disc is provided with a single inspected part, and the two relative boundaries of the inspected part have a defined range greater than or equal to twice the eccentric distance The detection area. The grinding machine tool with random eccentric orbital speed detection according to claim 1, wherein the inspected parts are located on the same extension line, one of the inspected parts is located in the center of the inspection area, and the inspected parts are located in the center of the inspection area. Two of the detecting parts are respectively arranged at an interval between the eccentric distance and one of the detected parts in the center. According to claim 1 or 2 or 3, the grinding machine tool with random eccentric orbital motion speed detection, wherein the grinding machine tool has a surface facing the grinding disc and does not change the position when the grinding disc performs the random eccentric orbital movement In order to detect the detected part and output a detection signal for the active detection part. According to claim 4, the grinding machine tool with random eccentric orbital motion speed detection, wherein the grinding machine tool has an information processing module connected to the active detection part and generating data of the random eccentric orbital speed per minute based on the detection signal group. According to claim 4, the grinding machine tool with random eccentric orbital motion speed detection, wherein the active detection part has an output part that emits a detection wave toward the detected part and a receiving part that is reflected by the detected part. The receiving part outputs the detection signal, and the detection wave is one selected from the group consisting of a light, a radio wave, and a sound wave. According to claim 4, the grinding machine tool with random eccentric orbital motion speed detection, wherein the projection position of the active detection element when the grinding disc is not rotating is located in the center of the detection area. According to claim 7, the grinding machine tool with random eccentric orbital movement speed detection, wherein the active detection member is arranged on the main body and located on the side facing the grinding disc. According to claim 4, the grinding machine tool with random eccentric orbital motion speed detection, wherein the active detection element generates the detection signal based on the intensity of the magnetic field changed by the detection element. According to claim 9, the grinding machine tool with free eccentric orbital movement speed detection, wherein the active detection member is arranged on the main body and located on the side facing the grinding disc. According to claim 4, the grinding machine tool with random eccentric orbital movement speed detection, wherein the active detection member is arranged on the main body and located on the side facing the grinding disc. According to claim 11, the grinding machine tool with random eccentric orbital motion speed detection, wherein the active detection member has an output part that emits a detection wave toward the detected part and a receiving part that receives the detection reflected by the detected part The receiving part outputs the detection signal, and the detection wave is one selected from the group consisting of a light, a radio wave, and a sound wave. According to claim 11, the grinding machine tool with random eccentric orbital motion speed detection, wherein the active detection element generates the detection signal based on the intensity of the magnetic field changed by the detection element. According to claim 12, the grinding machine tool with random eccentric orbital motion speed detection, wherein the grinding machine tool has an information processing module connected to the active detection part and generating a random eccentric orbital speed data per minute based on the detection signal group. According to claim 14, the grinding machine tool with random eccentric orbital motion speed detection, wherein the information processing module includes a waveform processing unit and a waveform processing unit connected to the waveform processing unit and analyzing a detection waveform signal output by the waveform processing unit. The arithmetic processing unit that generates the speed data of the random eccentric orbital movement per minute. According to claim 4, the grinding machine tool with random eccentric orbital speed detection, wherein the active detection component is externally hung outside the body by a connecting component. The grinding machine tool with random eccentric orbital motion speed detection according to claim 16, wherein the active detection part is provided on the side of the main body facing the grinding disc, and the grinding machine tool has a connection with the active detection part and based on the The detection signal generates an information processing module for eccentric orbital rotation speed data per minute, and the information processing module is arranged in the body and connected with the active detection component. According to claim 17, the grinding machine tool with random eccentric orbital motion speed detection, wherein the information processing module includes a waveform processing unit and a waveform processing unit connected to the waveform processing unit and analyzing a detected waveform signal output by the waveform processing unit. The arithmetic processing unit that generates the speed data of the random eccentric orbital movement per minute.

Images