A self-calibration device and method for picking up and releasing goods

Abstract

The present invention discloses a self-correction device and correction method for picking and releasing cargo points. The self-correction device comprises a positioning component, which is arranged on a clamp of an overhead crane and is located on a side of the clamp close to a product to be clamped. The positioning component is slidably connected to a bottom plate of the clamp along a lifting direction of the clamp. An elastic telescopic mechanism for resetting the positioning component after it is moved by force and a distance measuring mechanism for detecting the moving distance of the positioning component relative to the bottom plate after it is forced when clamping the product are arranged on the bottom plate of the clamp. The end of the sliding rod of the positioning component is used as a reference point for the moving distance of the clamp, and the matching state of the clamp and the product in the height direction is detected by triggering the first position detection sensor and the second position detection sensor at a certain height interval, thereby ensuring the stability of clamping and avoiding damage to the product, thereby realizing automatic correction of the clamping process.

Description

Technical Field

[0001] The present invention relates to the technical field of automated overhead crane systems, and in particular to a self-correcting device and method for picking up and releasing cargo points. Background Art

[0002] The main function of OHT is to transport FOUPs placed in the storage location, so the positioning accuracy of each axis (extension axis, lifting axis, rotation axis) is required to be very high (the error should not exceed 3mm).

[0003] The positioning accuracy of the lifting axis of the overhead crane is very high. If it does not descend to the right position, the goods cannot be picked up, or the clamping claws will directly clamp on the top side of the mushroom head, causing surface damage to the clamping claws and FOUP. In severe cases, the FOUP may be damaged, causing particles to fall and never contaminate the wafers. If it descends too much, the clamping claws and the corresponding slots of the FOUP will not be aligned correctly during clamping. When the lifting axis rises, it will cause a large shake, thereby damaging the wafers and causing huge losses. Therefore, the position accuracy of the lifting axis is required to be very high. At present, most manufacturers arrange the same storage positions as the official storage positions in the factory area to calibrate the positions at the calibration platform location. After finding a standard vehicle to calibrate the positions of each axis, other overhead cranes can calculate the positions corresponding to each storage position based on the machine difference. However, when the position accuracy error of some overhead cranes corresponding to the storage positions is too large during the handling process, the only way is to manually calibrate the positions at the corresponding storage positions. If there are many vehicles and positions, the steps of manually recalibrating the positions are complicated and the workload is huge. Summary of the invention

[0004] Technical purpose: In view of the shortcomings of the above-mentioned existing overhead crane lifting shaft positioning, the present invention discloses a self-correction device and correction method for picking up and releasing goods points, which can simultaneously perform lifting height correction and fine-tuning when the overhead crane is operating.

[0005] Technical solution: To achieve the above technical objectives, the present invention adopts the following technical solution:

[0006] A self-correction device for picking and releasing cargo points comprises a positioning component, wherein the positioning component is arranged on a clamp of an overhead crane and is located on the side of the clamp close to the product to be clamped, the positioning component is slidably connected to the bottom plate of the clamp along the lifting direction of the clamp, and an elastic telescopic mechanism for resetting the positioning component after being moved by force and a distance measuring mechanism for detecting the moving distance of the positioning component relative to the bottom plate after being forced when clamping the product are arranged on the bottom plate of the clamp.

[0007] Preferably, the positioning component of the present invention includes a centering plate for cooperating with the product to position the horizontal relative position of the product and the fixture. The surface shape of the centering plate close to the product matches the corresponding positioning position on the product. A sliding rod is arranged on the side of the centering plate close to the bottom plate. The sliding rod is penetrated on the bottom plate and the upper end of the sliding rod penetrates the surface of the bottom plate and is used as a reference point for its moving distance relative to the bottom plate. The distance measuring mechanism is arranged at the position where the end of the sliding rod is located.

[0008] Preferably, the distance measuring mechanism of the present invention includes a first position detection sensor and a second position detection sensor arranged along the axial direction of the sliding rod, the distance between the first position detection sensor and the second position detection sensor is the tolerance distance when the clamp clamps the product, and the relative position of the clamp and the product is confirmed by the triggering conditions of the first position detection sensor and the second position detection sensor.

[0009] Preferably, the elastic telescopic mechanism of the present invention is a telescopic spring sleeved on the sliding rod, the telescopic spring is located at the lower part of the base plate, one end of the telescopic spring abuts against the base plate, and the other end abuts against a truncated cone arranged on the sliding rod, and the telescopic spring applies a reset thrust to the sliding rod through the truncated cone.

[0010] The present invention discloses a method for automatically correcting the position of picking and placing goods based on the correction device, comprising the steps of:

[0011] S01. Select a reference crane, locate the lifting height of the fixture on the selected reference crane according to the cargo picking and placing position, and determine the reference descending distance;

[0012] S02, positioning the remaining overhead crane fixture descent distance according to the reference descent distance and the fixture height deviation values ​​of the remaining overhead cranes relative to the reference overhead crane;

[0013] S03. The overhead crane moves the product according to the confirmed clamp descent distance. During the clamping process, the descending distance of the overhead crane clamp is corrected according to the change in the distance after the distance measuring mechanism contacts the product, so that the clamping position on the clamp corresponds to the product.

[0014] Preferably, in step S05 of the present invention, the process of correcting the descent distance of the overhead crane clamp by means of a distance measuring mechanism includes: the clamp first descends to the pickup position according to a set height, and detects the triggering status of the first position detection sensor and the second position detection sensor after reaching the pickup position; when the first position detection sensor is not triggered, the clamp is controlled to descend a fixed distance until the first position detection sensor is triggered and the second position detection sensor is not triggered; when the first position detection sensor is triggered and the second position detection sensor is not triggered, the position of the clamp remains unchanged; when both the first position detection sensor and the second position detection sensor are triggered, the clamp is controlled to rise a fixed distance until the second position detection sensor is not triggered and the first position detection sensor remains in a triggered state.

[0015] Preferably, the fixed distance that the clamp of the present invention rises or falls is smaller than the distance between the first position detection sensor and the second position detection sensor.

[0016] Preferably, the distance between the first position detection sensor and the second position detection sensor of the present invention is less than or equal to the tolerance range of the relative position of the product in the height direction when the clamp clamps the product.

[0017] Beneficial effects: The self-correction device and correction method for picking up and releasing goods disclosed in the present invention have the following beneficial effects:

[0018] 1. The positioning component of the present invention is slidably connected to the positioning plate of the clamp through an elastic telescopic mechanism. The relative position of the clamp and the product is detected by the positioning component to achieve accurate clamping of the product by the clamp, thereby avoiding damage to the product.

[0019] 2. The end of the sliding rod of the positioning component of the present invention is used as a reference point for the moving distance of the clamp. By triggering the first position detection sensor and the second position detection sensor at a certain height interval, the matching state of the clamp and the product in the height direction is detected, thereby ensuring the stability of the clamping and avoiding damage to the product.

[0020] 3. When the present invention is performing height correction and positioning of the clamp, the distance of a single rise or fall is less than the distance between the two position detection sensors, thereby ensuring that the sliding rod will not exceed the range between the two sensors during adjustment, thereby ensuring the accuracy of the correction and adjustment and reducing the difficulty of the correction and adjustment operation.

[0021] 4. The present invention can control the accuracy of the correction positioning by controlling the distance between the two sensors, thereby being able to adapt to different working conditions and controlling the positioning error within a tolerance range. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below.

[0023] Figure 1 It is a schematic diagram of the clamp structure of the present invention;

[0024] Figure 2 It is a cross-sectional view of the positioning component of the present invention along the axis direction of the sliding rod;

[0025] Figure 3 A flow chart of the pickup point correction for the present invention;

[0026] Among them, 1-clamp, 2-bottom plate, 3-centering plate, 4-sliding rod, 5-first position detection sensor, 6-second position detection sensor, 7-round table, 8-elastic telescopic mechanism. DETAILED DESCRIPTION

[0027] Reference will now be made in detail to embodiments of the present disclosure, one or more examples of which are set forth herein below. Each embodiment and example is provided by explaining the apparatus, composition and materials of the present disclosure, rather than limiting. On the contrary, the following description provides a convenient illustration of an exemplary embodiment for implementing the present disclosure. In fact, it will be clear to those skilled in the art that various modifications and variations can be made in the teachings of the present disclosure without departing from the scope or spirit of the present disclosure. For example, a feature shown or described as a part of an embodiment can be used in conjunction with another embodiment to produce yet another embodiment. It is expected that the present disclosure covers such modifications and variations within the scope of the appended claims and their equivalents. Other objects, features and aspects of the present disclosure are disclosed in or clear from the following detailed description. It will be understood by those of ordinary skill in the art that this discussion is only a description of exemplary embodiments and is not intended to limit the wider aspects of the present disclosure.

[0028] like Figure 1 and Figure 2 As shown, the present invention provides a self-correcting device for picking up and releasing goods points, including a positioning component, which is arranged on the clamp 1 of the overhead crane and is located on the side of the clamp 1 close to the product to be clamped, and the positioning component is slidably connected to the bottom plate 2 of the clamp 1 along the lifting direction of the clamp 1, and an elastic telescopic mechanism 8 for resetting the positioning component after being moved by force and a distance measuring mechanism for detecting the moving distance of the positioning component relative to the bottom plate after being forced when clamping the product are arranged on the bottom plate 2 of the clamp 1.

[0029] The positioning component of the present invention is used to position the relative position of the fixture and the product during clamping, including horizontal positioning and height positioning. For horizontal positioning, corresponding positioning holes are generally provided on the top of the wafer box. For this purpose, the positioning component of the present invention includes a centering plate 3 for cooperating with the product to position the horizontal relative position of the product and the fixture 1. The surface shape of the centering plate 3 close to the side where the product is located matches the corresponding positioning position on the product, thereby realizing the horizontal positioning between the fixture and the product.

[0030] As for the height direction, due to the certain difference in the lifting heights of different overhead crane clamps, it is impossible to ensure that the set lifting height completely meets the clamping requirements of the product. The present invention arranges a sliding rod 4 on the side of the centering plate 3 close to the base plate 2. The sliding rod 4 is penetrated on the base plate 2 and the upper end penetrates the surface of the base plate 2 as a reference point for its moving distance relative to the base plate 2. The elastic telescopic mechanism 8 of the present invention is a telescopic spring sleeved on the sliding rod 4. The telescopic spring is located at the lower part of the base plate, one end of the telescopic spring abuts on the base plate 2, and the other end abuts on the round table 7 arranged on the sliding rod 4. The telescopic spring applies a reset thrust to the sliding rod 4 through the round table 7; the distance measuring mechanism is arranged at the position where the end of the sliding rod 4 is located, and then the displacement of the positioning plate 3 after contact with the wafer box can be detected through the distance measuring mechanism, thereby detecting and controlling the coordination between the clamp and the wafer box in the height direction, and ensuring the stability of subsequent clamping. At the same time, the present invention also arranges vertical lines on the surface of the clamp close to the wafer box, and the corresponding area of ​​the wafer box matches the vertical lines to avoid shaking of the wafer box during the clamping and moving process, and the accuracy of the clamping and placement positions can be guaranteed.

[0031] In a specific embodiment, the distance measuring mechanism of the present invention includes a first position detection sensor 5 and a second position detection sensor 6 arranged along the axial direction of the sliding rod 4. Both sensors are photoelectric sensors, and their positions are judged by the blocking state of the sliding rod 4. The distance between the first position detection sensor 5 and the second position detection sensor 6 is the tolerance distance when the clamp 1 clamps the product. The relative position of the clamp and the product is confirmed by the triggering status of the first position detection sensor 5 and the second position detection sensor 6, thereby ensuring the accuracy of clamping and avoiding damage to the product.

[0032] The present invention discloses a method for automatically correcting the position of picking and placing goods based on the correction device, comprising the steps of:

[0033] S01. Select a reference crane, locate the lifting height of the fixture on the selected reference crane according to the cargo picking and placing position, and determine the reference descent distance;

[0034] S02, positioning the remaining overhead crane fixture descent distance according to the reference descent distance and the fixture height deviation values ​​of the remaining overhead cranes relative to the reference overhead crane;

[0035] S03. The overhead crane moves the product according to the confirmed clamp descent distance. During the clamping process, the descending distance of the overhead crane clamp is corrected according to the change in the distance after the distance measuring mechanism contacts the product, so that the clamping position on the clamp corresponds to the product.

[0036] like Figure 3 As shown, the process of correcting the descending distance of the overhead travelling crane clamp by means of the distance measuring mechanism of the present invention includes: the clamp first descends to the picking-up position according to the set height, and detects the triggering status of the first position detection sensor and the second position detection sensor after arriving at the picking-up position; when the first position detection sensor is not triggered, the clamp is controlled to descend a fixed distance until the first position detection sensor is triggered and the second position detection sensor is not triggered; when the first position detection sensor is triggered and the second position detection sensor is not triggered, the position of the clamp remains unchanged; when both the first position detection sensor and the second position detection sensor are triggered, the clamp is controlled to rise a fixed distance until the second position detection sensor is not triggered and the first position detection sensor remains in the triggered state.

[0037] The fixed distance for the clamp of the present invention to rise or fall is smaller than the spacing between the first position detection sensor and the second position detection sensor, and the spacing between the first position detection sensor and the second position detection sensor is smaller than or equal to the tolerance range of the relative position of the clamp to the product in the height direction when the clamp clamps the product; the distance between the first position detection sensor and the second position detection sensor determines the positioning accuracy during clamping, and can be selected according to the clamping requirements of the specific scene to achieve flexible control.

[0038] Through the self-correction device and correction method for picking and placing goods of the present invention, automatic adjustments can be made during the operation of the overhead crane, without the need to go to the storage location to calibrate the points, thereby reducing the workload required for calibration and maintaining the continuous operation of the entire production line.

Claims

1. A self-calibration device for picking up and releasing goods, characterized in that: The invention comprises a positioning component, wherein the positioning component is arranged on a clamp (1) of an overhead crane and is located on a side of the clamp (1) close to a product to be clamped, the positioning component is slidably connected to a bottom plate (2) of the clamp (1) along a lifting direction of the clamp (1), and an elastic telescopic mechanism (8) is arranged on the bottom plate (2) of the clamp (1) for resetting the positioning component after it is moved under force, and a distance measuring mechanism is arranged on the bottom plate (2) of the clamp (1) for detecting a moving distance of the positioning component relative to the bottom plate after it is moved under force when clamping the product; The positioning component comprises a centering plate (3) for cooperating with the product to position the product and the fixture (1) horizontally relative to each other. The surface shape of the centering plate (3) on the side close to the product matches the corresponding positioning position on the product. A sliding rod (4) is arranged on the side of the centering plate (3) close to the bottom plate (2). The sliding rod (4) is penetrated on the bottom plate (2) and the upper end of the sliding rod (4) penetrates the surface of the bottom plate (2) and is used as a reference point for its moving distance relative to the bottom plate (2). A distance measuring mechanism is arranged at the position where the end of the sliding rod (4) is located. The distance measuring mechanism comprises a first position detection sensor (5) and a second position detection sensor (6) which are arranged along the axial direction of the sliding rod (4); the distance between the first position detection sensor (5) and the second position detection sensor (6) is a tolerance distance when the clamp (1) clamps the product; and the relative position of the clamp and the product is confirmed by the triggering conditions of the first position detection sensor (5) and the second position detection sensor (6).

2. A self-calibration device for picking up and releasing goods according to claim 1, characterized in that: The elastic telescopic mechanism (8) is a telescopic spring sleeved on the sliding rod (4). The telescopic spring is located at the bottom of the base plate. One end of the telescopic spring abuts against the base plate (2), and the other end abuts against a round table (7) provided on the sliding rod (4). The telescopic spring applies a resetting thrust to the sliding rod (4) via the round table (7).

3. A method for automatically correcting the position of picking up and releasing goods, using the self-correction device described in any one of claims 1-2, characterized in that: Includes steps: S01. Select a reference crane, locate the lifting height of the fixture on the selected reference crane according to the cargo picking and placing position, and determine the reference descending distance; S02, positioning the remaining overhead crane fixture descent distance according to the reference descent distance and the fixture height deviation values ​​of the remaining overhead cranes relative to the reference overhead crane; S03. The overhead crane clamps the product according to the confirmed clamp descent distance. During the clamping process, the descending distance of the overhead crane clamp is corrected according to the change in distance after the distance measuring mechanism contacts the product, so that the clamping position on the clamp corresponds to that on the product.

4. The method for automatically correcting the position of picking up and releasing goods according to claim 3 is characterized in that: In step S03, the process of correcting the descent distance of the overhead crane clamp by means of the distance measuring mechanism includes: the clamp first descends to the pickup position according to the set height, and detects the triggering status of the first position detection sensor and the second position detection sensor after reaching the pickup position; when the first position detection sensor is not triggered, the clamp is controlled to descend a fixed distance until the first position detection sensor is triggered and the second position detection sensor is not triggered; when the first position detection sensor is triggered and the second position detection sensor is not triggered, the position of the clamp remains unchanged; when both the first position detection sensor and the second position detection sensor are triggered, the clamp is controlled to rise a fixed distance until the second position detection sensor is not triggered and the first position detection sensor remains in the triggered state.

5. The method for automatically correcting the position of picking up and releasing goods according to claim 4 is characterized in that: The fixed distance that the clamp rises or falls is smaller than the distance between the first position detection sensor and the second position detection sensor.

6. The method for automatically correcting the position of picking up and releasing goods according to claim 4 is characterized in that: The distance between the first position detection sensor and the second position detection sensor is less than or equal to the tolerance range of the relative position of the product in the height direction when the clamp clamps the product.

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