A citrus fruit peeling flexible mechanical claw, processing device and processing method

Abstract

The present application relates to a kind of citrus fruit opening flexible mechanical claw, processing device and processing method;The citrus fruit opening flexible mechanical claw includes support, flexible opening and closing claw and posture switching mechanism;The flexible opening and closing claw includes mounting seat and multiple groups of flexible claw single finger;The inside and outside of each group of flexible claw single finger are respectively provided with inner pilot drive rope and outer pilot drive rope, and the inner pilot drive rope and outer pilot drive rope are fixed in the inside and outside of the flexible claw single finger by inner mounting block and outer mounting block;The posture switching mechanism is used to drive inner pilot drive rope and / or outer pilot drive rope movement, to drive flexible opening and closing claw between inwards once flexion state, outward once flexion state and twice flexion state switching.The citrus fruit opening flexible mechanical claw of the present application can accurately, stably, quickly open the skin of fruit, improve the production efficiency and processing quality of fruit in primary processing, reduce processing cost.

Description

Technical Field

[0001] This invention relates to the field of agricultural machinery, and in particular to a flexible mechanical claw for peeling citrus fruits, a processing device, and a processing method. Background Technology

[0002] Dried tangerine peel (Chenpi) is a traditional Chinese medicine made from the dried peel of the mature fruit of the citrus plant (Citrus reticulata) and its cultivated varieties. It possesses properties such as regulating qi and strengthening the spleen, as well as drying dampness and resolving phlegm, and has high application value in the field of traditional Chinese medicine. Among them, Guangchenpi, as a premium variety of dried tangerine peel, has high medicinal value and market recognition due to its unique geographical environment, growth cycle, and processing technology. It also possesses the attribute of being both food and medicine, and has broad application prospects in food processing, health products, and traditional Chinese medicine preparations.

[0003] With the continuous growth of market demand, the Guangchenpi (Guangdong tangerine peel) industry is gradually developing towards large-scale and standardized operations. However, the initial processing of Guangchenpi still suffers from problems such as low automation, insufficient processing efficiency, and poor consistency in processing quality. Traditional processing methods still rely heavily on manual labor. Among these, the peeling and pulp separation of fresh citrus fruits is a crucial step in the initial processing of tangerine peel, directly affecting subsequent drying, storage, and quality evaluation. Fresh fruit peels are soft, easily deformed, and irregular in shape, and the tissue connection between the pulp and peel is complex. During the peeling and pulp separation process, processing difficulties such as material positioning problems, damage to the peel tissue, and difficulty in controlling processing precision can easily occur. As a result, the peeling and pulp separation of fresh citrus fruits has long relied on manual operation, which cannot meet the demands of modern production for high-efficiency, high-consistency, and intelligent processing.

[0004] To address the aforementioned issues, there is an urgent need to develop an automated processing device capable of adapting to the unique shape and flexible processing requirements of citrus fruit peels, thereby improving operational stability and processing efficiency during the peeling process. Flexible mechanical grippers, as crucial actuators for flexible grasping, can reliably clamp irregular and fragile materials through special structural designs or the properties of special materials. This is expected to solve the problems of insufficient adaptability and easy damage to fresh fruit materials inherent in traditional rigid clamps during the fresh fruit peeling process. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a flexible mechanical claw for peeling citrus fruits. The flexible mechanical claw for peeling citrus fruits can accurately, stably and quickly peel fruits, thereby improving the production efficiency and processing quality of primary processing of citrus fruits and reducing processing costs.

[0006] The second objective of this invention is to provide a processing apparatus employing the aforementioned flexible mechanical claw for peeling citrus fruits.

[0007] A third objective of the present invention is to provide a processing method for the above-described processing apparatus.

[0008] The technical solution of the present invention to solve the above-mentioned technical problems is:

[0009] A flexible mechanical gripper for peeling citrus fruits includes a support frame, flexible opening and closing grippers mounted on the support frame, and a posture switching mechanism. The flexible opening and closing grippers include a mounting base and multiple sets of flexible gripper fingers mounted on the mounting base. The multiple sets of flexible gripper fingers are arranged circumferentially. Each set of flexible gripper fingers has an inner pilot drive rope and an outer pilot drive rope on its inner and outer sides, respectively. The inner and outer pilot drive ropes are fixed to the inner and outer sides of the flexible gripper finger by inner and outer mounting blocks, respectively, and extend along the length of the flexible gripper finger. The posture switching mechanism uses... The inner pilot drive rope and / or the outer pilot drive rope are driven to move, thereby driving the flexible opening and closing claw to switch between an inward single-bending state, an outward single-bending state, and a double-bending state. In the inward single-bending state, each of the multiple sets of flexible claws in the flexible opening and closing claw is in a single-bending state with the claw tip pointing inward. In the outward single-bending state, each of the multiple sets of flexible claws in the flexible opening and closing claw is in a single-bending state with the claw tip pointing outward. In the double-bending state, each of the multiple sets of flexible claws in the flexible opening and closing claw is in a double-bending state with the claw tip pointing outward.

[0010] Preferably, both the inner mounting block and the outer mounting block are in multiple sets, and the multiple sets of inner mounting blocks and the multiple sets of outer mounting blocks are arranged at equal intervals along the length direction of the flexible claw finger; the flexible claw finger is made of thermoplastic polyester elastomer.

[0011] Preferably, the attitude switching mechanism includes a first attitude switching mechanism for driving the inner pilot drive rope to move and a second attitude switching mechanism for driving the outer pilot drive rope to move.

[0012] Preferably, the bracket includes a first support plate and a second support plate arranged from top to bottom, wherein the first support plate and the second support plate are connected by a vertically arranged first connecting shaft; there are multiple sets of first connecting shafts arranged in a circle; the second support plate is connected to the mounting base by a vertically arranged second connecting shaft; there are multiple sets of second connecting shafts arranged in a circle.

[0013] Preferably, the first attitude switching mechanism includes a lower drive motor mounted on the second support plate and an inner irregular flange, wherein the lower drive motor and the inner irregular flange are connected by a first lead screw transmission mechanism; the first lead screw in the first lead screw transmission mechanism is mounted on the main shaft of the lower drive motor, and the first lead screw nut in the first lead screw transmission mechanism is mounted on the inner irregular flange; the upper ends of the inner pilot drive ropes of the multiple sets of flexible claws of the flexible opening and closing claws all pass vertically upward through the first clearance hole in the mounting base and are fixed to the outer side of the inner irregular flange; the inner irregular flange is provided with a first guide hole that mates with the second connecting shaft.

[0014] Preferably, the second attitude switching mechanism includes an upper drive motor, a star-shaped flange, and an outer irregular flange mounted on the second support plate. The upper drive motor is located above the lower drive motor and is coaxially arranged with the main shafts of the upper and lower drive motors. The upper drive motor and the star-shaped flange are connected via a second lead screw transmission mechanism. The second lead screw in the second lead screw transmission mechanism is mounted on the main shaft of the upper drive motor, and the second lead screw nut in the second lead screw transmission mechanism is mounted on the star-shaped flange. The outer irregular flange... The outer shaped flange is positioned between the second support plate and the inner shaped flange. The outer shaped flange is connected to the star-shaped flange by multiple sets of vertically arranged third connecting shafts. The multiple sets of third connecting shafts are arranged in a circle. The second support plate is provided with a second guide hole that mates with the third connecting shaft. The outer shaped flange is provided with a clearance groove for avoiding the inner shaped flange. The upper ends of the outer pilot drive ropes of the multiple sets of flexible claw fingers in the flexible opening and closing claw pass vertically upward through the second clearance hole in the mounting base and are then fixed to the outer side of the outer shaped flange.

[0015] Preferably, the flexible claw finger has spherical protrusions on both its inner and outer surfaces.

[0016] A processing apparatus includes a worktable, a peeling device disposed on the worktable, a conveying device for conveying citrus fruits one by one to the peeling device, and a control device. The peeling device includes a robotic arm and a flexible robotic claw for peeling citrus fruits disposed at the end of the robotic arm. The conveying device includes a conveyor seat and a conveying drive mechanism for moving the conveyor seat. The conveyor seat fixes the citrus fruits by vacuum adsorption.

[0017] Preferably, a vision detection module is provided below the mounting base. The vision detection module includes an image acquisition module and an image processing module. The image acquisition module is used to acquire a static image of a citrus fruit and transmit the static image to the image processing module. The image processing module performs image processing on the static image, extracts the static features of the citrus fruit, calculates the static two-dimensional coordinate data of the cut surface of the citrus fruit, and transmits the static two-dimensional coordinate data to the control device. After processing, the control device outputs high and low level signals and PWM signals to the motor drive module. The motor drive module controls the direction of the upper and lower drive motors according to the high and low level signals, and controls the speed of the upper and lower drive motors during the peeling operation according to the PWM signals.

[0018] A processing method includes the following steps:

[0019] S1. Before peeling, make three cuts at the navel of the citrus fruit; after peeling, the robotic arm places the citrus fruit on the suction cup of the conveying device, which then transports it to the peeling station of the peeling device; when the citrus fruit reaches the peeling station, the robotic arm moves the flexible robotic claw of the citrus fruit peeling downwards to a preset position above the citrus fruit, preparing for the peeling operation.

[0020] S2. The vision detection module acquires images of citrus fruits and obtains the coordinate information of the cut opening of the citrus fruits. The control device controls the upper drive motor and the lower drive motor to move. By adjusting the movement stroke of the inner and outer irregular flanges, the pre-tension displacement of the inner and outer pilot drive ropes is changed, thereby controlling the flexible opening and closing claw to extend into the cut opening of the citrus fruits in a secondary bending state.

[0021] S3. After the flexible opening and closing claw extends into the cut of the citrus fruit, by adjusting the pre-tension displacement of the inner and outer pilot drive ropes, the flexible opening and closing claw switches from a secondary flexion state to an inward primary flexion state. At this time, the claw tips of the multiple sets of flexible claw fingers in the flexible opening and closing claw face inward. The mechanical arm drives the flexible opening and closing claw to move downward, causing the flexible claw fingers to cut along the surface of the fruit flesh along the connecting meridian between the peel and the fruit flesh until the flexible claw fingers descend to the bottom of the fruit flesh and envelop the entire fruit flesh.

[0022] S4. After reaching the bottom of the citrus fruit, by controlling the pre-tension displacement of the inner and outer pilot drive ropes, the claw tips of the multiple sets of flexible claws in the flexible opening and closing claw change from an inward flexion state to an outward flexion state. At this time, the claw tips of the multiple sets of flexible claws in the flexible opening and closing claw face outward. During this switching process, the multiple sets of flexible claws in the flexible opening and closing claw will gradually stretch the peel until the pulp is completely exposed. Again, by controlling the pre-tension displacement of the inner and outer pilot drive ropes, the claw tips of the multiple sets of flexible claws in the flexible opening and closing claw change from an outward flexion state to an inward flexion state, and the multiple sets of flexible claws in the flexible opening and closing claw wrap the completely exposed pulp.

[0023] S5. The end effector of the robotic arm drives the flexible opening and closing claw to rotate, cutting off the remaining connection between the pulp and the peel. The robotic arm controls the flexible opening and closing claw to lift upwards, removing the wrapped pulp and completing the separation of the peel and pulp of citrus fruits.

[0024] Compared with the prior art, the present invention has the following advantages:

[0025] 1. The flexible mechanical claw for peeling citrus fruits of the present invention, through its special secondary bending ability of flexible opening and closing claws, effectively adapts to the citrus fruit processing objects during peeling and pulping, improves the stability and automation level of the peeling process, reduces damage to the peel tissue during peeling and pulping, and achieves non-destructive separation of citrus fruit peel and pulp. This avoids problems such as juice splashing and mechanical damage to the peel caused by manual peeling operations, and provides technical support for the intelligent upgrading of the primary processing stage of Guangchenpi (dried tangerine peel).

[0026] 2. The flexible mechanical claw for peeling citrus fruits of the present invention does not require precise matching with the shape of the citrus fruit. The flexible claw first extends into the cut of the citrus fruit in a double-bending, double-bending state, and then switches to a single-bending, single-bending state to open the peel. The flexible claw is made of flexible sheet material. Relying on the material's own characteristics, it can adaptively change its posture along the contour of the fruit pulp when wrapping it, without the need for additional adjustment. It has passive adaptive capability and can be adapted to fruits of different sizes and specifications.

[0027] 3. The flexible mechanical claw for peeling citrus fruits of the present invention can accurately, stably and quickly complete the peeling operation of citrus fruits; by utilizing the buckling characteristics of the material, the peeling operation can achieve rapid response, reduce the peeling failure rate caused by slippage and the problem of incomplete peeling caused by poor fit between the claw and the citrus fruit, improve the production efficiency and processing quality of the initial processing of citrus fruits, and reduce labor costs. Attached Figure Description

[0028] Figures 1-3 These are schematic diagrams from three different perspectives of the first form of the flexible mechanical claw for peeling citrus fruits according to the present invention.

[0029] Figure 4 This is a perspective view of the second form of the flexible mechanical claw for peeling citrus fruits according to the present invention.

[0030] Figure 5 This is a perspective view of the third form of the flexible mechanical claw for peeling citrus fruits according to the present invention.

[0031] Figure 6 This is a diagram showing the mechanical response of a single finger of a flexible claw under low preload.

[0032] Figure 7 This is a diagram showing the mechanical response of a single finger of a flexible claw under high preload.

[0033] Figure 8 This is a perspective view of the processing apparatus of the present invention.

[0034] Figure 9 This is a three-dimensional view of the skin-opening device.

[0035] Figure 10 This is a flowchart illustrating the workflow of the flexible opening and closing claws in this invention, which involves skin entry, skin cutting, skin stretching, and meat extraction.

[0036] In the diagram: 1- Flexible robotic claw for peeling citrus fruits, 2- Robotic arm, 3- Conveying drive mechanism, 4- Conveying seat, 5- Lower drive motor, 6- Upper drive motor, 7- Star flange, 8- Outer irregular flange, 9- Inner irregular flange, 10- Mounting seat, 11- Flexible claw single finger, 12- Inner pilot drive rope, 13- Inner mounting block, 14- Outer pilot drive rope, 15- Outer mounting block, 16- Third connecting shaft, 17- First support plate, 18- Second support plate, 19- Vision inspection module, 20- Connecting shaft. Detailed Implementation

[0037] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0038] The tea branch mandarin orange is spherical or nearly ellipsoidal in shape. Therefore, the embodiments of this invention use the tea branch mandarin orange as the fruit to be peeled. The technical solution of this invention will be further described in detail in conjunction with the tea branch mandarin orange.

[0039] Example 1

[0040] See Figures 1-7The flexible mechanical claw 1 for peeling citrus fruits of the present invention includes a support, a flexible opening and closing claw disposed on the support, and a posture switching mechanism for driving the flexible opening and closing claw to switch between a primary flexion state and a secondary flexion state. The flexible opening and closing claw includes a mounting base 10 and multiple sets of flexible claw fingers 11 disposed on the mounting base 10; the multiple sets of flexible claw fingers 11 are arranged circumferentially; each set of flexible claw fingers 11 has an inner pilot drive rope 12 and an outer pilot drive rope 14 respectively disposed on its inner and outer sides. The movable rope 14 is fixed to the inner and outer sides of the flexible claw finger 11 by the inner mounting block 13 and the outer mounting block 15, respectively, and extends along the length direction of the flexible claw finger 11; wherein, there are multiple sets of the inner mounting block 13 and the outer mounting block 15, and the multiple sets of inner mounting blocks 13 and the multiple sets of outer mounting blocks 15 are equidistantly arranged along the length direction of the flexible claw finger 11; the attitude switching mechanism is used to drive the inner pilot drive rope 12 and / or the outer pilot drive rope 14 to move, so as to drive the flexible opening and closing claw in an inward flexion state (e.g. Figure 4 As shown), outward first buckling state (such as...) Figure 1 (as shown) and secondary buckling state (as shown) Figure 5 The system switches between the following states: In the first inward flexion state, each of the multiple sets of flexible claws in the flexible opening and closing claw is in a single-bent state with the claw tip pointing inward; In the first outward flexion state, each of the multiple sets of flexible claws in the flexible opening and closing claw is in a single-bent state with the claw tip pointing outward; In the second flexion state, each of the multiple sets of flexible claws in the flexible opening and closing claw is in a double-bent state with the claw tip pointing outward.

[0041] When the flexible opening and closing claw is pulled by the inner pilot drive rope 12 and / or the outer pilot drive rope 14, it first produces a single circular arc state of bending, which is called "first buckling" in the mechanics of materials. As the traction force increases, the flexible opening and closing claw bends further on the basis of the first bending, so that the flexible opening and closing claw forms a double circular arc shape with two bending points. This state is called "secondary buckling" in the mechanics of materials. The secondary buckling refers to the following: after the structure undergoes initial bending and enters the equilibrium path after yielding, a stability bifurcation phenomenon occurs again on this equilibrium path when the load continues to increase. At this bifurcation point, the original equilibrium state of the system is broken, and it transitions to a new stable stage with different deformation modes. Generally speaking, this type of large deformation phenomenon often occurs in thin rods, thin sheets, and shell components. The flexible opening and closing claw can complete the deformation with an extremely fast response speed during the deformation switching process from single circular arc to double circular arc to single circular arc, thereby realizing the rapid switching of the fruit peeling posture. This invention uses a flexible thin sheet as the flexible single finger of the flexible opening and closing claw, and utilizes its rapid response characteristics in the transition from primary buckling to secondary buckling to control the flexible opening and closing claw to complete a series of operations such as peeling, cutting, supporting, and removing the flesh.

[0042] During the peeling process, the control device controls the operation of the upper drive motor 6 and the lower drive motor 5. The posture switching mechanism controls the flexible opening and closing claw to switch from a single-bending, single-bending state to a double-bending, double-bending state, so that the claw tip of the flexible opening and closing claw extends into the cut of the tea branch mandarin orange. Then, the posture of the flexible opening and closing claw is adjusted to switch to the single-bending state. At the same time, the robotic arm 2 drives the flexible opening and closing claw to increase the downward displacement. During the process of enveloping the pulp, the peel is separated from the pulp along the contour of the pulp. After the separation is completed, the robotic arm 2 drives the flexible opening and closing claw to remove the pulp, thus completing the entire peeling process. In the entire peeling process, from peeling, cutting, stretching, and removing the flesh, the flexible opening and closing claws utilize their inherent secondary bending ability to switch postures according to the work position and process nodes. The flexible opening and closing claws have suitable toughness, which can avoid claw deformation or fruit peel damage caused by excessive traction during the peeling and stretching processes. At the same time, the flexible opening and closing claws have passive adaptive characteristics, which can adapt to citrus fruits of different sizes and shapes, improve the work efficiency of the citrus fruit peeling process, and reduce the work cost.

[0043] See Figures 1-7 The flexible claw finger 11 is configured in three groups; each group of flexible claw finger 11 is provided with twelve mounting blocks, and mounting blocks are arranged on both the front and back sides of each group of flexible claw finger 11, that is, there are six inner mounting blocks 13 and six outer mounting blocks 15, so as to facilitate the adjustment of the posture of the flexible claw finger 11. The six inner mounting blocks 13 and the six outer mounting blocks 15 on the front and back sides are arranged symmetrically in correspondence; the inner mounting blocks 13 and the outer mounting blocks 15 in the same group are riveted and fixed by two sets of rivets.

[0044] See Figures 1-7 One end of the inner pilot drive rope 12 and the outer pilot drive rope 14 is fixed to the mounting block at the tip of the flexible claw finger 11, and the other end passes through the fastening bolts of the other mounting blocks in sequence and is fixed to the mounting bolt. Then, the mounting bolt is screwed into the threaded holes of the inner irregular flange 9 and the outer irregular flange 8. In this embodiment, both the inner pilot drive rope 12 and the outer pilot drive rope 14 are made of fishing line with high toughness, high wear resistance and high tensile strength, so that they are not easy to break or wear during the pulling operation; at the same time, the line is flexible and smooth, which can effectively reduce the frictional resistance generated when passing through the guide structure, making the transmission response more sensitive and direct.

[0045] See Figures 1-7 Each set of flexible claw fingers 11 is uniformly provided with spherical protrusions of the same size; when performing fruit peel cutting operations, the spherical protrusions can transform the surface contact friction between the flexible claw fingers 11 and the fruit peel into point contact friction between the spherical protrusions and the fruit peel, thereby reducing the wear caused by the fruit peel on the flexible claw fingers 11 during the peeling process, and further improving the service life of the flexible claw sheet.

[0046] See Figures 1-7 Before opening the skin, the preload of the flexible claw finger 11 needs to be adjusted. By increasing the screwing amount of the preload bolt, the preload of the inner and outer pilot drive ropes can be increased or decreased to prevent the flexible opening and closing claw from being damaged due to excessive preload, or the expected operation effect from being too small.

[0047] See Figures 1-7 The flexible claw finger 11 is made of thermoplastic polyester elastomer (TPEE) as a flexible sheet required for skin-opening operations. TPEE is a polymer material that combines the high elasticity of rubber with the excellent processing properties of plastics. It possesses high toughness, high wear resistance, excellent oil resistance, and tear resistance, allowing the flexible claw finger 11 to undergo stable deformation under the tension of the inner and outer pilot drive ropes 12 and 14, and is not easily damaged or broken, effectively adapting to the repeated bending and tearing conditions of skin-opening operations. Simultaneously, this thermoplastic polyester elastomer has good thermoplastic processing characteristics, allowing for rapid molding through conventional processes such as injection molding and extrusion, resulting in high processing efficiency. Furthermore, damaged components can be replaced at low cost, effectively reducing equipment maintenance costs.

[0048] To further improve the peel-flesh separation effect of the flexible claw finger 11, this invention optimizes the thickness structure of the flexible claw finger 11, that is, the thickness of the flexible claw finger 11 at the working end that extends into the peel is less than the thickness near the assembly end. This allows the flexible claw finger 11 to better conform to the surface of the fruit flesh and undergo flexible deformation when the flexible opening and closing claw moves downward, accurately separating the connecting meridians between the peel and the fruit flesh, thereby greatly improving the smoothness and integrity of peeling and separating the peel from the flesh of the tea branch mandarin orange.

[0049] See Figures 1-7 The length of the flexible claw finger 11 should not be too large. If the length of the flexible claw finger 11 is too large, the control stability of the claw tip posture will be poor. Considering that the peel will deform and displace when it is peeled, the visual detection module 19 collects the peeling progress of the peel in real time during the peeling operation and feeds the progress information back to the control device to ensure that the peeling operation is complete and reliable. After the peeling process is completed, the conveying device will transport the tea branch tangerine to the next station to perform the subsequent processing process.

[0050] See Figures 1-7 The bracket includes a first support plate 17 and a second support plate 18 arranged from top to bottom, wherein the first support plate 17 and the second support plate 18 are connected by a vertically arranged first connecting shaft; there are multiple sets of the first connecting shaft, and the multiple sets of the first connecting shaft are arranged in a circle; the second support plate 18 is connected to the mounting base 10 by a vertically arranged second connecting shaft; there are multiple sets of the second connecting shaft, and the multiple sets of the second connecting shaft are arranged in a circle.

[0051] In addition, the first connecting shaft and the second connecting shaft can also be coaxially arranged, and the first connecting shaft and the second connecting shaft are an integral structure (i.e., using a single connecting shaft 20); the first support plate 17 and the mounting base 10 are directly connected through the connecting shaft 20.

[0052] See Figures 1-7 The attitude switching mechanism includes a first attitude switching mechanism for driving the inner pilot drive rope 12 to move and a second attitude switching mechanism for driving the outer pilot drive rope 14 to move.

[0053] The first attitude switching mechanism includes a lower drive motor 5 and an inner irregular flange 9 mounted on the second support plate 18. The lower drive motor 5 and the inner irregular flange 9 are connected by a first lead screw transmission mechanism. The first lead screw in the first lead screw transmission mechanism is mounted on the main shaft of the lower drive motor 5, and the first lead screw nut in the first lead screw transmission mechanism is mounted on the inner irregular flange 9. The upper ends of the inner pilot drive ropes 12 of the multiple sets of flexible claw fingers 11 of the flexible opening and closing claws all pass vertically upward through the first clearance hole in the mounting base 10 and are fixed to the outer side of the inner irregular flange 9. The inner irregular flange 9 is provided with a first guide hole that cooperates with the second connecting shaft.

[0054] The second attitude switching mechanism includes an upper drive motor 6, a star-shaped flange 7, and an outer irregular flange 8 mounted on the second support plate 18. The upper drive motor 6 is located above the lower drive motor 5, and the upper drive motor 6 and the main shaft of the lower drive motor 5 are coaxially arranged. The upper drive motor 6 and the star-shaped flange 7 are connected via a second lead screw transmission mechanism. The second lead screw in the second lead screw transmission mechanism is mounted on the main shaft of the upper drive motor 6, and the second lead screw nut in the second lead screw transmission mechanism is mounted on the star-shaped flange 7. The outer irregular flange 8 is disposed on the... Between the second support plate 18 and the inner irregular flange 9, the outer irregular flange 8 and the star flange 7 are connected by multiple sets of vertically arranged third connecting shafts 16; the multiple sets of third connecting shafts 16 are arranged in a circle; the second support plate 18 is provided with a second guide hole that mates with the third connecting shaft 16; the outer irregular flange 8 is provided with a clearance groove for avoiding the inner irregular flange 9; the upper ends of the outer pilot drive ropes 14 in the multiple sets of flexible claw fingers 11 of the flexible opening and closing claws all pass vertically upward through the second clearance hole in the mounting base 10 and are fixed to the outer side of the outer irregular flange 8.

[0055] In this embodiment, both the upper drive motor 6 and the lower drive motor 5 are stepper motors. The reason for this is that stepper motors can achieve simple open-loop control, have low cost, and stable output torque under low-speed conditions. The skin-opening operation of this invention does not require high speed and extremely high control precision, so stepper motors are selected as motion control execution components.

[0056] Example 2

[0057] See Figures 8-9 The processing apparatus of the present invention includes a workbench, a peeling device disposed on the workbench, a conveying device for conveying tea branch tangerines one by one to the peeling station of the peeling device, and a control device. The peeling device includes a robotic arm 2 and a flexible mechanical claw 1 for peeling citrus fruits disposed at the end of the robotic arm 2. The conveying device includes a conveying seat 4 and a conveying drive mechanism 3 for driving the conveying seat 4 to move. The conveying seat 4 fixes the tea branch tangerines by vacuum adsorption.

[0058] Before peeling, the skin of the tangerine needs to be cut at the navel area. The tangerine is then transferred to a conveyor system and transported to the peeling station of the peeling device. The conveyor system is equipped with a conveyor seat 4, which has suction cups. During the transfer and peeling process, the suction cups secure the tangerine, preventing displacement of the peeling position due to transport vibrations and avoiding problems such as a crooked opening or inability to peel properly. After the conveyor system transports the tangerine to the peeling station, the visual detection module 19 of the flexible mechanical claw 1 for peeling citrus fruits locates the peeling position. The robotic arm 2 drives the flexible mechanical claw 1 to the preset position, whereby the flexible mechanical claw 1 performs the peeling operation.

[0059] In this embodiment, the conveying device is a horizontal conveyor. A conveyor seat 4 is mounted on the conveyor belt of this device, and a suction cup is installed inside the conveyor seat 4. The size of the suction cup is adapted to the bottom contour of the tea branch orange, completely covering its bottom. After the tea branch orange has undergone the opening (i.e., peeling) process, an external conveying device (e.g., a handling robot) transfers the tea branch orange to the suction cup of the conveyor seat 4. An air pipe is connected to the bottom of the suction cup. After the tea branch orange is placed in position, the air pipe connected to the suction cup activates negative pressure suction, fixing the tea branch orange to the suction cup through negative pressure adsorption, ensuring that the opening of the tea branch orange always faces upwards, guaranteeing consistent positioning at the work station. Next, the conveying device operates and transports the tea branch orange to the working position aligned with the robotic arm 2 at the peeling station. After the tea branch orange is precisely positioned, the robotic arm 2 moves the flexible robotic claw 1 for peeling citrus fruits to the opening position of the tea branch orange and adjusts and controls the bending posture of the multiple sets of flexible claw fingers 11 in the flexible opening and closing claw to complete the automated peeling operation of the tea branch orange in coordination with the movement of the robotic arm 2.

[0060] See Figures 8-9 The control device includes a power supply regulator module, a microcontroller module, an upper motor drive module, and a lower motor drive module. The power supply regulator module is the energy supply unit for the entire control device, converting the external input voltage into the low-voltage DC power required by the microcontroller module and the operating voltage required by the upper and lower motor drive modules. When the external input voltage fluctuates, the power supply regulator module can suppress voltage fluctuations and maintain a stable output operating voltage. In this embodiment, the LM2596S module is selected as the power supply regulator module. The LM2596S module has an adjustable output voltage range of 1.25V-37V, a maximum output current of 3A, and overcurrent protection.

[0061] In this embodiment, the power supply regulator module, microcontroller module, upper motor drive module, and lower motor drive module are soldered onto the same circuit board and mounted as a whole on the robotic arm 2. The modules are electrically connected via multiple wires. Additionally, wires extend from inside the robotic arm 2 to electrically connect the upper motor drive module and the lower motor drive module to the upper drive motor 6 and the lower drive motor 5, respectively. During the skin-opening action, the microcontroller module receives control signals and transmits them to the corresponding motor drive modules. The motor drive modules then output drive signals to drive the upper drive motor 6 and the lower drive motor 5 to complete the corresponding actions.

[0062] See Figures 8-9 A vision detection module 19 is provided below the mounting base 10. The vision detection module 19 is located at the symmetrical center of the three flexible claw fingers 11, and the length of the flexible claw fingers 11 is designed to ensure that the tea branch orange will not interfere with the image acquisition module when the flexible opening claws perform the peeling action downwards. The vision detection module 19 includes an image acquisition module (camera) and an image processing module (image processing chip). The image acquisition module is used to acquire a static image of the tea branch orange and send the static image to the image processing module. The image processing module performs image processing on the static image, extracts the static features of the tea branch orange, calculates the static two-dimensional coordinate data of the peeling opening of the tea branch orange, and transmits the static two-dimensional coordinate data to the control device. After processing, the control device outputs high and low level signals and PWM signals to the motor drive module. The motor drive module controls the direction of the upper drive motor 6 and the lower drive motor 5 according to the high and low level signals, and controls the speed of the upper drive motor 6 and the lower drive motor 5 during the peeling operation according to the PWM signals. The working height direction is determined by the preset parameters of the robotic arm.

[0063] See Figure 10Before the peeling process begins, three cuts are made at the navel of the tangerine. Then, a robotic arm places the peeled tangerine onto the conveyor seat 4 of the conveyor device, which transports it to the peeling station via a conveyor belt. Once the tangerine reaches the peeling station, the flexible opening and closing claws maintain an enveloping posture. The image acquisition module takes a picture of the tangerine, capturing a static image, which is then transmitted to the image processing module. The image processing module sequentially performs grayscale processing, binarization, filtering and denoising, and normalization on the static image. Image processing operations are performed to extract static features of the tea branch tangerine from the static image. After further processing by the image processing module, static two-dimensional coordinate data of the tangerine peel cutting surface is obtained, and the static two-dimensional coordinate data is sent to the microcontroller module. After completing the processing, the microcontroller module outputs high and low level signals and PWM signals to the motor drive module. The motor drive module controls the direction of the upper drive motor 6 and the lower drive motor 5 according to the high and low level signals. At the same time, the motor drive module controls the speed of the upper drive motor 6 and the lower drive motor 5 during the peeling process according to the PWM signal.

[0064] After the visual detection module 19 completes the recognition process, the flexible claw finger 11 is in an initial single-circular arc bending state. Subsequently, the control device sends a control signal to keep the upper drive motor 6 stationary and drive the lower drive motor 5 to move the inner irregular flange 9 upward. At this time, the flexible claw finger 11 is in an envelope posture, i.e., a first-order buckling state. The first-order buckling refers to the flexible claw finger 11 being subjected to external stress, which is insufficient to resist the external stress, causing deformation and entering the equilibrium stage after the first yield, resulting in bending and forming a new force balance in the bending state. The inner pilot drive rope 12 of the flexible claw finger 11 is constrained by the fastening nut of the inner irregular flange 9. The inner irregular flange 9 continues to move upward, continuously applying traction force to the flexible claw finger 11. The original bending force balance of the flexible claw finger 11 is broken, and the flexible claw finger 11 continues to deform under the action of traction force, seeking a stable state after yielding again. The flexible claw finger 11 bends again, and this state is the second-order buckling. When the flexible claw finger 11 is in a double-bending state, it bends further on top of its original envelope. The cut size formed after peeling the tea branch tangerine is usually small, and the flexible claw, relying solely on its single-bending state, cannot easily penetrate the peel for the peeling operation; however, the double-bending state reduces the space occupied by the claw tip. Therefore, the upper drive motor 6 remains stationary, while the lower drive motor 5 drives the inner shaped flange 9 upward, switching the flexible claw finger 11 to a double-bending state, allowing the claw tip to smoothly penetrate the cut and providing conditions for subsequent peeling. After the flexible claw penetrates the cut, the lower drive motor 5 continues to drive the inner shaped flange 9 upward, while the upper drive motor 6 drives the star-shaped flange 7 downward. The star-shaped flange 7, through the third connecting shaft 16, drives the outer shaped flange 8 downward. Under this condition, the traction force on the flexible claw decreases, and the flexible claw transitions from a double-bending state to a single-bending state. Then, the robotic arm 2 continues to move downwards, while the upper drive motor 6 and the lower drive motor 5 remain unchanged. The flexible opening and closing claw cuts downwards along the gap between the peel and the pulp until it reaches the bottom of the tea branch mandarin orange. The robotic arm 2 then drives the robotic claw to rotate, thereby completely separating the pulp from the peel. The pulp is then removed, and the peel is transferred to the next processing step.

[0065] The flexible claw finger 11 exhibits abrupt mechanical changes during the transition from a "single-fold buckling" state to a "secondary-fold buckling" state, and vice versa; for example... Figure 6 and Figure 7As shown, when the applied stress exceeds this mechanical abrupt change point, the mechanical response curve will undergo a rapid abrupt change. Utilizing this mechanical property, the flexible opening and closing claw can achieve rapid response during the skin-opening preparation and opening operation stages, thereby effectively shortening the skin-opening time. The state switching of the flexible claw's single finger 11 from the "primary buckling" state to the "secondary buckling" state can be achieved by adjusting the preload of the inner and outer pilot drive ropes. For example... Figure 6 As shown, under low preload conditions, the secondary buckling state is difficult to maintain. The antagonistic load increment can overcome the geometric constraints brought by the pilot side, and the flexible claw finger 11 will return to the single-circle arc state corresponding to the primary buckling; as Figure 7 As shown, under high preload conditions, after the flexible claw finger 11 completes the transition from primary buckling to secondary buckling, this secondary buckling state can be stably maintained. Based on the above characteristics, the preload force can be differentiated for different stages of skin opening. For example, when preparing to open the peel, by maintaining the original pre-tension of the outer pilot drive rope 14 and increasing the pre-tension of the inner pilot drive rope 12, the flexible claw finger 11 quickly switches from a single arc state to a double arc state. This achieves both rapid response and constrains the posture of the flexible claw finger 11, ensuring that the claw tip of the flexible claw finger 11 points downwards, making it easier to reach into the cutting opening and hook the peel. Subsequently, while keeping the pre-tension of the inner pilot drive rope 12 unchanged, the pre-tension of the outer pilot drive rope 14 is increased to prompt the flexible opening claw to tear the peel. Once the visual detection module 19 recognizes that the peel opening has expanded to a set degree, the pre-tension of the inner pilot drive rope 12 is reduced, while the pre-tension of the outer pilot drive rope 14 remains unchanged. The flexible claw finger 11 quickly returns to a single arc state. In this way, the peeling action can be completed step by step without adapting to the shape contour of the tea branch mandarin orange, thus achieving rapid peeling.

[0066] See Figures 8-10 This embodiment provides a fruit peeling method based on buckling mechanism, using tea branch tangerines as the treatment object. The specific steps are as follows:

[0067] S1. After the tea branch orange is peeled, the handling robot places the tea branch orange on the suction cup of the conveying device, which then transports it to the peeling station of the peeling device. The control device transmits the peeling signal to the robotic arm 2. When the robotic arm 2 receives the peeling signal, it moves the flexible robotic claw 1 for peeling citrus fruits downward to the preset position above the tea branch orange, preparing for the peeling operation.

[0068] S2, the visual detection module 19 acquires images of the tea branch tangerine and obtains the coordinate information of the tangerine's cut opening; the control device controls the upper drive motor 6 and the lower drive motor 5 to move, and adjusts the movement stroke of the inner irregular flange 9 and the outer irregular flange 8 to change the pre-tension displacement of the inner pilot drive rope 12 and the outer pilot drive rope 14, thereby controlling the flexible claw to extend into the cut opening in a double-bending posture (secondary bending state).

[0069] S3. After the flexible opening and closing claw extends into the cutting opening, the pretension of the inner pilot drive rope 12 and the outer pilot drive rope 14 is adjusted to switch the flexible opening and closing claw from a double-bending state (secondary bending state) to a single-bending state (primary bending state). The flexible opening and closing claw moves downward through the robotic arm 2, and the single finger 11 of the flexible claw cuts the connecting meridian between the peel and the pulp along the surface of the pulp, descends to the bottom of the pulp and envelops the entire pulp. Then, the end effector of the robotic arm 2 drives the flexible opening and closing claw to rotate, cut off the last connecting part between the pulp and the peel, and realize the separation of the peel and pulp of the tea branch mandarin orange. Finally, the flexible opening and closing claw removes the pulp, leaving the peel, and completes the peeling process.

[0070] In the above process, the flexible opening and closing claw has good bending flexibility. When performing peeling operations between the peel and pulp, it can adaptively deform according to the curvature of the pulp and gradually wrap the pulp in an enveloping posture. The end effector of the robotic arm 2 drives the peeling claw to move in a predetermined direction, so that the front end of the flexible opening and closing claw can cut, peel and separate the connection area between the peel and pulp. While achieving the initial separation of peel and pulp, the flexible opening and closing claw continues to expand the peel and pulp separation area through rotation. After the flexible claw reaches the preset working depth, the whole peeling and pulping process of the citrus fruit can be completed.

[0071] Upon reaching the bottom of the tea branch tangerine, the control device manipulates the upper drive motor 6 and the lower drive motor 5 to control the pre-tension displacement of the inner and outer pilot drive ropes, thereby increasing the traction force of the outer pilot drive rope 14 and decreasing the traction force of the inner pilot drive rope 12. This causes the flexible opening and closing claw to change from the inward bending state of the original peeling state to the outward bending state. During this switching process, the flexible claw finger 11 will gradually stretch the peel until the pulp is completely exposed, thus completing the peeling state. Then, the traction force distribution of the inner and outer pilot drive ropes is changed to return to the inward wrapping state (i.e., the inward bending state). The flexible opening and closing claw wraps the completely exposed pulp, and then the robotic arm 2 controls the flexible opening and closing claw to lift upward and remove the pulp, thus completing the separation of the peel and pulp of the tea branch tangerine. Then, preparation is made for the next peeling action of the tea branch tangerine.

[0072] In this embodiment, the switching of the buckling state can be achieved by distributing the pretension of the inner pilot drive rope 12 and the outer pilot drive rope 14. When a rapid adjustment of the posture is required, the pretension of one side of the pilot drive rope is kept constant while the pretension of the other side of the pilot drive rope is increased. This causes the flexible claw finger 11 to yield and enter a new force equilibrium stage, achieving rapid operation response and shortening the skin-opening time. Specifically, in the skin-opening preparation stage, the upper drive motor 6 remains stationary, while the lower drive motor 5 drives the inner irregular flange 9 to move upward, increasing the pretension displacement of the inner pilot drive rope 12. The pretension of the inner pilot drive rope 12 increases accordingly. When the pretension rises to a set threshold, the flexible claw finger 11 can no longer bear the load in the original equilibrium state, yields, and enters the next equilibrium stage, generating a step response. The posture of the flexible claw finger 11 changes rapidly, extending into the skin-opening incision in a double-bending posture. Then, adjust the pre-tightening displacement of the inner pilot drive rope 12 and the outer pilot drive rope 14 to make the flexible opening and closing claw obtain sufficient antagonistic load, and then step back to the single bending state; in conjunction with the adjustment of the vertical position of the flexible opening and closing claw during the peeling process, the flexible opening and closing claw can cut the connecting meridians along the gap between the peel and the pulp to complete the peeling operation of the tea branch mandarin orange.

[0073] The above are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above content. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A flexible mechanical claw for peeling citrus fruits, characterized in that, The device includes a support frame, a flexible opening / closing claw mounted on the support frame, and a posture switching mechanism. The flexible opening / closing claw includes a mounting base and multiple sets of flexible claw fingers mounted on the mounting base. The multiple sets of flexible claw fingers are arranged circumferentially. Each set of flexible claw fingers has an inner pilot drive rope and an outer pilot drive rope on its inner and outer sides, respectively. The inner and outer pilot drive ropes are fixed to the inner and outer sides of the flexible claw fingers by inner and outer mounting blocks, respectively, and extend along the length of the flexible claw fingers. The posture switching mechanism is used to drive the inner pilot... The drive rope and / or the outer pilot drive rope move to drive the flexible opening and closing claw to switch between an inward single-bending state, an outward single-bending state, and a double-bending state. In the inward single-bending state, each of the multiple sets of flexible claws in the flexible opening and closing claw is in a single-bending state with the claw tip pointing inward. In the outward single-bending state, each of the multiple sets of flexible claws in the flexible opening and closing claw is in a single-bending state with the claw tip pointing outward. In the double-bending state, each of the multiple sets of flexible claws in the flexible opening and closing claw is in a double-bending state with the claw tip pointing outward.

2. The flexible mechanical claw for peeling citrus fruits according to claim 1, characterized in that, Both the inner mounting block and the outer mounting block are in multiple sets, and the multiple sets of inner mounting blocks and multiple sets of outer mounting blocks are arranged at equal intervals along the length direction of the flexible claw finger; the flexible claw finger is made of thermoplastic polyester elastomer.

3. The flexible mechanical claw for peeling citrus fruits according to claim 1, characterized in that, The attitude switching mechanism includes a first attitude switching mechanism for driving the inner pilot drive rope and a second attitude switching mechanism for driving the outer pilot drive rope.

4. The flexible mechanical claw for peeling citrus fruits according to claim 3, characterized in that, The bracket includes a first support plate and a second support plate arranged from top to bottom, wherein the first support plate and the second support plate are connected by a vertically arranged first connecting shaft; there are multiple sets of first connecting shafts arranged in a circle; the second support plate is connected to the mounting base by a vertically arranged second connecting shaft; there are multiple sets of second connecting shafts arranged in a circle.

5. The flexible mechanical claw for peeling citrus fruits according to claim 4, characterized in that, The first attitude switching mechanism includes a lower drive motor mounted on the second support plate and an inner irregular flange. The lower drive motor and the inner irregular flange are connected by a first lead screw transmission mechanism. The first lead screw in the first lead screw transmission mechanism is mounted on the main shaft of the lower drive motor, and the first lead screw nut in the first lead screw transmission mechanism is mounted on the inner irregular flange. The upper ends of the inner pilot drive ropes of the multiple sets of flexible claws of the flexible opening and closing claws all pass vertically upward through the first clearance hole in the mounting base and are fixed to the outer side of the inner irregular flange. The inner irregular flange is provided with a first guide hole that mates with the second connecting shaft.

6. The flexible mechanical claw for peeling citrus fruits according to claim 5, characterized in that, The second attitude switching mechanism includes an upper drive motor, a star-shaped flange, and an outer irregular flange mounted on the second support plate. The upper drive motor is located above the lower drive motor and is coaxially arranged with the main shafts of the upper and lower drive motors. The upper drive motor and the star-shaped flange are connected via a second lead screw transmission mechanism. The second lead screw in the second lead screw transmission mechanism is mounted on the main shaft of the upper drive motor, and the second lead screw nut in the second lead screw transmission mechanism is mounted on the star flange. The outer irregular flange is... The outer irregular flange is positioned between the second support plate and the inner irregular flange. The outer irregular flange is connected to the star-shaped flange by multiple sets of vertically arranged third connecting shafts. The multiple sets of third connecting shafts are arranged in a circle. The second support plate is provided with a second guide hole that mates with the third connecting shaft. The outer irregular flange is provided with a clearance groove for avoiding the inner irregular flange. The upper ends of the outer pilot drive ropes of the multiple sets of flexible claw fingers in the flexible opening and closing claws all pass vertically upward through the second clearance hole in the mounting base and are then fixed to the outer side of the outer irregular flange.

7. The flexible mechanical claw for peeling citrus fruits according to claim 6, characterized in that, The flexible claw finger has spherical protrusions on both its inner and outer surfaces.

8. A processing apparatus employing the flexible mechanical claw for peeling citrus fruits as described in claim 7, characterized in that, The device includes a workbench, a peeling device mounted on the workbench, a conveying device for transporting citrus fruits one by one to the peeling device, and a control device. The peeling device includes a robotic arm and a flexible robotic claw for peeling citrus fruits located at the end of the robotic arm. The conveying device includes a conveyor seat and a conveying drive mechanism for moving the conveyor seat. The conveyor seat fixes the citrus fruits by vacuum adsorption.

9. The processing apparatus according to claim 8, characterized in that, A vision detection module is located below the mounting base. The vision detection module includes an image acquisition module and an image processing module. The image acquisition module acquires a static image of a citrus fruit and transmits the static image to the image processing module. The image processing module performs image processing on the static image, extracts the static features of the citrus fruit, calculates the static two-dimensional coordinate data of the cut surface of the citrus fruit, and transmits the static two-dimensional coordinate data to the control device. After processing, the control device outputs high and low level signals and PWM signals to the motor drive module. The motor drive module controls the direction of the upper and lower drive motors according to the high and low level signals, and controls the speed of the upper and lower drive motors during the peeling operation according to the PWM signals.

10. A processing method for the processing apparatus of claim 9, characterized in that, Includes the following steps: S1. Before peeling, make three cuts at the navel of the citrus fruit; after peeling, the robotic arm places the citrus fruit on the suction cup of the conveying device, which then transports it to the peeling station of the peeling device; when the citrus fruit reaches the peeling station, the robotic arm moves the flexible robotic claw of the citrus fruit peeling downwards to a preset position above the citrus fruit, preparing for the peeling operation. S2. The vision detection module acquires images of citrus fruits and obtains the coordinate information of the cut opening of the citrus fruits. The control device controls the upper drive motor and the lower drive motor to move. By adjusting the movement stroke of the inner and outer irregular flanges, the pre-tension displacement of the inner and outer pilot drive ropes is changed, thereby controlling the flexible opening and closing claw to extend into the cut opening of the citrus fruits in a secondary bending state. S3. After the flexible opening and closing claw extends into the cut of the citrus fruit, by adjusting the pre-tension displacement of the inner and outer pilot drive ropes, the flexible opening and closing claw switches from a secondary flexion state to an inward primary flexion state. At this time, the claw tips of the multiple sets of flexible claw fingers in the flexible opening and closing claw face inward. The mechanical arm drives the flexible opening and closing claw to move downward, causing the flexible claw fingers to cut along the surface of the fruit flesh along the connecting meridian between the peel and the fruit flesh until the flexible claw fingers descend to the bottom of the fruit flesh and envelop the entire fruit flesh. S4. After reaching the bottom of the citrus fruit, by controlling the pre-tension displacement of the inner and outer pilot drive ropes, the claw tips of the multiple sets of flexible claws in the flexible opening and closing claw change from an inward flexion state to an outward flexion state. At this time, the claw tips of the multiple sets of flexible claws in the flexible opening and closing claw face outward. During this switching process, the multiple sets of flexible claws in the flexible opening and closing claw will gradually stretch the peel until the pulp is completely exposed. Again, by controlling the pre-tension displacement of the inner and outer pilot drive ropes, the claw tips of the multiple sets of flexible claws in the flexible opening and closing claw change from an outward flexion state to an inward flexion state, and the multiple sets of flexible claws in the flexible opening and closing claw wrap the completely exposed pulp. S5. The end effector of the robotic arm drives the flexible opening and closing claw to rotate, cutting off the remaining connection between the pulp and the peel. The robotic arm controls the flexible opening and closing claw to lift upwards, removing the wrapped pulp and completing the separation of the peel and pulp of citrus fruits.

Images