Fresh tea leaf lossless screening device and screening method

Abstract

The invention belongs to the technical field of screening or screening in operation transportation, and particularly relates to a fresh tea leaf lossless screening device and a screening method.The fresh tea leaf lossless screening device comprises a tea leaf containing bin with the upper end open; a horizontal leaf suction partition plate is arranged in the middle of the interior of the tea containing bin, and a plurality of densely-distributed air suction holes are formed in the leaf suction partition plate in a penetrating mode. An air pressure sensor is further arranged below the tea leaf suction partition plate and in the tea leaf containing bin; the bottom wall of the tea leaf accommodating bin is connected with an air suction pump which is used for forming negative pressure below the leaf suction partition plate; the getter pump is in signal connection with a controller for adjusting the operating power of the getter pump; the air pressure sensor is in signal connection with the controller; the tea containing bin is movably connected to a movement mechanism, and the movement mechanism is configured to enable the tea containing bin to be inverted into an inverted state with an opening in the upper end facing downwards from a forward state with the opening in the upper end facing upwards, and enable the tea containing bin in the inverted state to stay at a first position and a second position respectively. During use, damage to fresh tea leaves in the screening process can be effectively reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of screening or sieving in operation and transportation, and in particular relates to a non-destructive screening device and a screening method for fresh tea leaves. Background Art

[0002] After the tea leaves are harvested manually or mechanically, the harvested fresh tea leaves usually include the required types of one bud and one leaf, one bud and two leaves, one bud and three leaves, and one bud and four leaves. The fresh tea leaf types mentioned in the fresh tea leaf sorting and identification technology disclosed in CN118447328A can be referred to. In order to classify the quality, the fresh tea leaves need to be sorted. The efficiency of manual sorting is low, so many automatic screening equipment have appeared. See the vibration screening machine for tea sorting disclosed in Chinese patent CN206392410U. Through two layers of vibration screening nets, the upper layer screens out larger tea leaves, such as one bud and three leaves, one bud and four leaves, and the lower layer screens out smaller tea leaves, such as one bud and one leaf, one bud and two leaves; there is also a bud leaf screening device for tea processing disclosed in CN117139162A, which uses the rotation of the screening chamber and cooperates with vibration to screen the tea leaves entering the screening chamber for multiple times, and the tea leaves are classified into a variety of different standards and discharged by the filter. Most of the existing automatic tea screening equipment are like this, which comes into contact with fresh tea leaves through screens, filters, etc. However, during the screening and tea leaves passing through the screen holes, the hard screens and filters will inevitably cause or partially cause scratches on the delicate fresh tea leaves, affecting the quality of the produced fresh tea leaves. Therefore, further improvement of tea screening equipment is needed. Summary of the invention

[0003] In view of the above-mentioned deficiencies in the prior art, the technical problem to be solved by the present invention is to provide a damage-free screening device and screening method for fresh tea leaves, so as to avoid the problem that the current automatic tea screening equipment easily causes damage to the fresh tea leaves during the screening process, thereby achieving the effect of reducing the damage to the fresh tea leaves during the screening process and improving the quality of the tea leaves.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0005] The non-destructive screening device for fresh tea leaves comprises a tea accommodating bin with an open top; a horizontal leaf suction partition is fully laid in the middle of the tea accommodating bin for laying fresh tea leaves, and a plurality of densely distributed air suction holes are penetrated on the leaf suction partition; an air pressure sensor or a gas flow sensor is also arranged in the tea accommodating bin below the leaf suction partition; an air suction pump is connected to the bottom wall of the tea accommodating bin, and the air suction pump is used to form a negative pressure inside the tea accommodating bin below the leaf suction partition; the air suction pump signal is connected to a controller for adjusting the operating power of the air suction pump, and the air pressure sensor or the gas flow sensor is connected to the controller signal;

[0006] The tea accommodating bin is movably connected to a moving mechanism, and the moving mechanism is constructed to be able to invert the tea accommodating bin from a normal state with its upper end opening facing upward to an inverted state with its upper end opening facing downward, and to make the tea accommodating bin in the inverted state stay in a first position and a second position, respectively.

[0007] To further improve the above technical solution, storage mechanisms are provided below the first position and the second position respectively.

[0008] Furthermore, the movement mechanism includes an oval-shaped circular track, two straight sections of the oval-shaped circular track are horizontally arranged and respectively located above and below the vertical direction, and the tea accommodating bin is slidably connected to the circular track. During the sliding of the tea accommodating bin along the circular track, its upper end opening is always facing the inner side of the circular track. When the tea accommodating bin slides along the circular track to the upper straight section, the first position and the second position can be formed respectively.

[0009] Furthermore, the storage mechanism includes a transmission belt, which passes through the inner side of the annular track, and a storage box is provided below the end of the transmission belt.

[0010] Furthermore, the tea storage bin is in the shape of a rectangular parallelepiped, with connecting shafts extending along its length direction at both ends respectively connected to the driving wheels through the connecting shafts, the annular track includes two parallel and opposite slide rails, and the two slide rails have oval guide grooves on their opposite surfaces, the tea storage bin is located between the two slide rails, and the driving wheels at both ends are rollingly connected in the corresponding guide grooves.

[0011] Furthermore, a plurality of air pressure sensors or gas flow sensors are provided in the tea storage bin, which are respectively connected to two sides of the tea storage bin and spaced apart along the length direction thereof;

[0012] There are multiple air suction pumps, which are arranged at intervals along the length direction of the tea accommodating bin.

[0013] The present invention also relates to a method for non-destructive screening of fresh tea leaves, which is implemented based on the above-mentioned non-destructive screening device for fresh tea leaves:

[0014] Make the tea storage bin in a positive state, spread the fresh tea leaves to be screened on the leaf suction partition.

[0015] The suction pump creates negative pressure inside the tea storage bin below the leaf suction partition, thereby creating suction force on the fresh tea leaves laid on the leaf suction partition through the suction holes;

[0016] The air pressure sensor or the gas flow sensor detects the air pressure value, and adjusts the operating power of the air suction pump through the controller to ensure that the fresh tea leaves will not fall when the tea storage bin is inverted; and to prevent the fresh tea leaves from falling during the process of the tea storage bin being inverted from the forward state to the inverted state, and before the inverted state reaches the designed position;

[0017] The movement mechanism inverts the tea containing bin from the normal state to the inverted state;

[0018] The tea storage bin stays at the first position, and the controller adjusts and reduces the operating power of the air pump in combination with the measured air pressure value. The smaller fresh tea leaves fall down under their own weight due to the reduced suction force.

[0019] The tea storage bin stays at the second position, and the controller adjusts and further reduces the operating power of the air pump in combination with the measured air pressure value. The larger fresh tea leaves fall under the action of their own weight due to the reduced suction force, thereby separating the smaller fresh tea leaves from the larger fresh tea leaves.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] The non-destructive screening device and method of fresh tea leaves of the present invention utilizes the difference in suction force on fresh tea leaves of different sizes and adjusts the operating power of the suction pump at the first position and the second position during the process of classifying fresh tea leaves of different sizes, so that fresh tea leaves of different sizes fall at different positions, thereby achieving screening. The disadvantages of using a hard screen for screening are avoided, and the scratch damage to fresh tea leaves caused by the screening process is effectively reduced, thereby improving the quality of tea leaves. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a separate three-dimensional diagram of the tea accommodating bin in a specific embodiment;

[0023] Figure 2 It is a schematic structural diagram of a device for non-destructive screening of fresh tea leaves according to a specific embodiment;

[0024] Figure 3 for Figure 2 A schematic cross-sectional view of the tea storage bin at the middle AA section;

[0025] Figure 4 It is a three-dimensional diagram of a device for non-destructive screening of fresh tea leaves according to a specific embodiment;

[0026] Among them, there are tea accommodating bin 50, leaf suction partition 51, air suction hole 52, air pressure sensor 53, air suction pump 54, driving wheel 55, circular track 56, slide rail 57, straight section 58, first position 59, second position 60, guide rail groove 61, storage mechanism 62, first conveyor belt 63, first storage box 64, second conveyor belt 65, second storage box 66, guide plate 67. DETAILED DESCRIPTION

[0027] The specific implementation modes of the present invention will be further described in detail below in conjunction with the accompanying drawings.

[0028] See also Figure 1-Figure 3The non-destructive screening device for fresh tea leaves in a specific embodiment comprises a tea accommodating bin 50 with an open top; a horizontal leaf suction partition 51 is fully paved in the middle of the tea accommodating bin 50 for paving fresh tea leaves, that is, the leaf suction partition 51 is abutted and connected to the inner side of the side wall of the corresponding tea accommodating bin 50 on all sides without leaving any gaps; a plurality of densely distributed air suction holes 52 are formed on the leaf suction partition 51, and the air suction holes 52 are circular. Densely distributed specifically means that the diameter of the air suction holes 52 is such that fresh tea leaves cannot pass through, and they are only used for ventilation. In order to ensure the suction force and the effective area, as many air suction holes 52 as possible are formed on the leaf suction partition 51; below the leaf suction partition 51 , an air pressure sensor 53 is also provided in the tea accommodating bin 50; an air suction pump 54 is connected to the bottom wall of the tea accommodating bin 50, whose air suction port faces the inside of the tea accommodating bin 50 and the air exhaust port faces the outside, and the air suction pump 54 is used to continuously form a negative pressure inside the tea accommodating bin 50 below the leaf suction partition 51, thereby forming suction on the fresh tea leaves laid on the leaf suction partition 51 through the air suction hole 52 (air intake); the air suction pump 54 signal is connected to a controller (not shown in the figure) for adjusting the operating power of the air suction pump 54, and the air pressure sensor 53 is connected to the controller signal so that the controller can adjust the operating power of the air suction pump 54 according to the measured air pressure value.

[0029] The tea accommodating bin 50 is movably connected to a moving mechanism, and the moving mechanism is configured to invert the tea accommodating bin 50 from a normal state with its upper end opening upward to an inverted state with its upper end opening downward, and to make the tea accommodating bin 50 in the inverted state stay at a first position 59 and a second position 60. The first position 59 and the second position 60 are different positions for fresh tea leaves to fall, and of course, the moving mechanism can also restore the tea accommodating bin 50 to the initial position of the normal state.

[0030] When in use, the tea holding bin 50 is first in a forward state, and the fresh tea leaves to be screened are spread flat on the leaf suction partition 51; the air suction pump 54 runs and forms a negative pressure inside the tea holding bin 50 below the leaf suction partition 51, thereby forming suction on the fresh tea leaves laid on the leaf suction partition 51 through the air suction holes 52; the air pressure sensor 53 detects the air pressure value, and adjusts the operating power of the air suction pump 54 through the controller to ensure that the fresh tea leaves will not fall when the tea holding bin 50 is in an inverted state.

[0031] Then, the motion mechanism inverts the tea storage bin 50 from the forward state to the inverted state. The tea storage bin 50 stays at the first position 59 first, and the controller reduces the operating power of the air pump 54, and adjusts it in combination with the measured air pressure value to maintain the stability of the operating power. The smaller fresh tea leaves fall under the action of their own weight due to the reduced suction force;

[0032] The motion mechanism drives the tea accommodating bin 50 to move to the second position 60 and stop there. The controller further reduces the operating power of the air pump 54 and adjusts the operating power in combination with the measured air pressure value to maintain the stability of the operating power. The larger fresh tea leaves fall down under the action of their own weight due to the reduced suction force, thereby separating the smaller fresh tea leaves from the larger fresh tea leaves.

[0033] The aforementioned smaller fresh tea leaves refer to fresh tea leaves with one bud and one leaf, or one bud and two leaves, and the larger fresh tea leaves refer to fresh tea leaves with one bud and three leaves, or one bud and four leaves. Smaller fresh tea leaves have fewer, smaller leaves and a higher curl, and have a smaller contact area on the leaf suction baffle 51, a smaller area covering the air suction hole 52, and a smaller suction force. Larger fresh tea leaves have a larger contact area on the leaf suction baffle 51, a larger area covering the air suction hole 52, and a larger suction force. Although the larger fresh tea leaves have a relatively larger deadweight, the weight of the tea leaves themselves is very light. During the process of reducing the operating power of the air pump 54, the change in the suction force determines the order of falling, which is a key parameter of the falling order, so the aforementioned device and method can be used for screening. The specific operating power values ​​of the air pump 54 at each stage in the process are obtained by actual measurement through a certain sample size test in the early stage, and then preset in the controller for corresponding control and adjustment, and the parameters can be adjusted and modified when necessary.

[0034] The non-destructive screening device for fresh tea leaves of the embodiment utilizes the difference in suction forces exerted on tea leaves of different sizes during the process of classifying fresh tea leaves of different sizes, and adjusts the operating power of the suction pump 54 at different screening drop positions to achieve screening, thereby avoiding the process of passing through a hard screen, effectively reducing the scratching damage to the fresh tea leaves caused by the screening process, and improving the quality of the tea leaves.

[0035] During implementation, the controller and the power supply for powering each electronic device can be set on the tea storage bin 50. The controller can also be set in the control room and connected to the air pressure sensor 53 and the suction pump 54 signal by wireless transmission. The motion mechanism can realize the relevant actions, which are not limited to the specific ones. It can be a mechanical arm connected to the tea storage bin 50, which has three degrees of freedom and a turntable drive. Storage mechanisms 62, such as collection boxes, are respectively provided below the first position 59 and the second position 60 to classify and collect the smaller fresh tea leaves and larger fresh tea leaves that fall. If it is necessary to classify the fresh tea leaves more finely, the motion mechanism can be added to drive the different positions where the inverted tea storage bin 50 stays, which are not limited to the first position 59 and the second position 60. Combined with the controller's control of the operating power of the suction pump 54, more detailed classification can be achieved.

[0036] Please see again Figure 2 and Figure 4In this embodiment, the motion mechanism includes an annular track 56 in the shape of an oval circle, and two straight sections 58 of the annular track 56 in the shape of an oval circle are arranged horizontally and respectively located at the upper and lower sides in the vertical direction. The tea storage bin 50 is slidably connected to the annular track 56. During the sliding process of the tea storage bin 50 along the annular track 56, its upper end opening is always facing the inner side of the annular track 56, so as to form a positive state on the lower straight section 58 and an inverted state on the upper straight section 58. When the tea storage bin 50 slides along the annular track 56 to the upper straight section 58, it can stay at different positions respectively and form the first position 59 and the second position 60 correspondingly. It can be understood that the straight section 58 of the annular track 56 has a certain length, which can provide the tea storage bin 50 to stay at the first position 59 and the second position 60 respectively. The inner side of the annular track 56 has a chain or belt circulation mechanism, which connects the tea storage bin 50 and drives it to slide in a circumferential circulation.

[0037] The storage mechanism 62 includes a transmission belt, which passes through the inner side of the annular track 56, and a storage box is provided below the end of the transmission belt. The transmission belt below the first position 59 is a first transmission belt 63, and the corresponding storage box is a first storage box 64. The transmission belt below the second position 60 is a second transmission belt 65, and the corresponding storage box is a second storage box 66.

[0038] Please continue to see Figure 4 Specifically, the tea accommodating bin 50 is in a rectangular shape, and its two ends are respectively connected with connecting shafts extending along its length direction and connected to driving wheels 55 through the connecting shafts, specifically two sets of connecting shafts and driving wheels 55 spaced apart in the width direction. The annular track 56 includes two parallel and opposite slide rails 57, and the two slide rails 57 are provided with oblong guide grooves 61 on the opposite surfaces. The tea accommodating bin 50 is located between the two slide rails 57, and the driving wheels 55 at both ends are rollingly connected in the corresponding guide grooves 61. The driving wheel 55 is equipped with a driving motor (not shown in the figure), which is connected by a wireless signal control of the controller. Different track segments are adapted to control the corresponding rotation directions of the driving wheel 55, driving the tea storage bin 50 to move circumferentially along the guide groove 61; when the arc segment at one end of the guide groove 61 rises, it can appropriately use the inertia of the lower straight segment 58 when moving. If necessary, it can also assist the lifting machinery (not shown in the figure) installed nearby to help the tea storage bin 50 rise from the forward state through the arc segment of the guide groove 61 to the inverted state; after the tea leaves are classified, the arc segment at the other end of the guide groove 61 is driven to move downward or slide with the help of its own weight, and the inverted state returns to the forward state.

[0039] Regarding the arrangement of the two parallel slide rails 57, a chain rail plate type circulation machine for circulating operation can also be arranged on the opposite inner side surfaces, and the ends of the tea storage bin 50 in the length direction are respectively fixedly connected to the chain rail plate through two extended connecting shafts, and the chain rail plate type circulation machine drives it to move in a circumferential circulation.

[0040] The circumferential circular movement method can take one circle of movement as one working step in each classification process, and the movement trajectory is regular, which is convenient for counting and operation implementation.

[0041] Please see again Figure 1 and Figure 3 In order to more accurately control the suction force of each area on the leaf suction partition 51, a plurality of air pressure sensors 53 are provided in the tea storage bin 50, which are respectively connected to both sides of the tea storage bin 50 and arranged at intervals along the length direction thereof; a plurality of air suction pumps 54 are also provided, which are arranged at intervals along the length direction of the tea storage bin 50. When the suction force is uneven and the local suction force is insufficient, the power of the adjacent air suction pump 54 can be correspondingly controlled to increase to ensure the use effect.

[0042] Please see again Figure 4 , guide plates 67 extending upward and outward are provided on both sides of the roller frame where the transmission belt is located, and the distance between the guide plates 67 and the two slide rails 57 is corresponding to or greater; the lower edge of the guide plate 67 extends to the upper side edge of the transmission belt. In this way, it is possible to avoid the fallen fresh tea leaves from falling on the outside of the transmission belt as much as possible, and ensure that the classified tea leaves eventually fall into the storage box. During implementation, the roller frame where the transmission belt is located, the slide rail 57, the storage box and other components that need to be fixed are all fixedly arranged and connected to a fixed ground or a fixed equipment frame. They are conventional fixed connections and are not shown in the accompanying drawings. The transmission belt, the roller frame where it is located, the fixed connection, the guide plate 67, etc. do not interfere with the circumferential circulation movement of the tea storage bin 50.

[0043] During implementation, the air pressure sensor 53 in the tea storage bin 50 may also use a gas flow sensor (not shown in the figure). During feedback control, the gas flow sensor can detect the pressure and flow in the space below the leaf suction baffle 51 in the tea storage bin 50. Combined with the air pressure value and instantaneous flow, it can better reflect the coverage of the fresh tea leaves on the suction holes 52 and the gas parameters in the space below the leaf suction baffle 51 in the tea storage bin 50. The controller can control and adjust the operating power of the suction pump 54 based on the feedback of the gas flow sensor on the two parameters of pressure and flow, which has a higher accuracy in achieving the use effect, but the control programming logic is relatively more complicated and the cost is higher.

[0044] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A non-destructive screening device for fresh tea leaves, comprising a tea accommodating bin with an open top; characterized in that: A horizontal leaf suction partition is fully laid in the middle of the tea storage bin for laying fresh tea leaves, and a plurality of densely distributed air suction holes are arranged on the leaf suction partition; an air pressure sensor or a gas flow sensor is also arranged in the tea storage bin below the leaf suction partition; an air suction pump is connected to the bottom wall of the tea storage bin, and the air suction pump is used to form a negative pressure inside the tea storage bin below the leaf suction partition; the air suction pump signal is connected to a controller for adjusting the operating power of the air suction pump, and the air pressure sensor or the gas flow sensor is connected to the controller signal; The tea accommodating bin is movably connected to a moving mechanism, and the moving mechanism is constructed to be able to invert the tea accommodating bin from a normal state with its upper end opening facing upward to an inverted state with its upper end opening facing downward, and to make the tea accommodating bin in the inverted state stay in a first position and a second position, respectively.

2. The non-destructive screening device for fresh tea leaves according to claim 1, characterized in that: Storage mechanisms are provided below the first position and the second position, respectively.

3. The non-destructive screening device for fresh tea leaves according to claim 2, characterized in that: The movement mechanism includes an oval-shaped circular track, two straight sections of the oval-shaped circular track are horizontally arranged and respectively located above and below the vertical direction, and the tea accommodating bin is slidably connected to the circular track. During the sliding of the tea accommodating bin along the circular track, its upper end opening is always facing the inner side of the circular track. When the tea accommodating bin slides along the circular track to the upper straight section, the first position and the second position can be formed respectively.

4. The non-destructive screening device for fresh tea leaves according to claim 3, characterized in that: The storage mechanism comprises a transmission belt which passes through the inner side of the annular track, and a storage box is arranged below the end of the transmission belt.

5. The non-destructive screening device for fresh tea leaves according to claim 3, characterized in that: The tea storage bin is in the shape of a rectangular parallelepiped, with connecting shafts extending along its length direction at both ends respectively connected to the driving wheels through the connecting shafts. The annular track includes two parallel and opposite slide rails, and the opposite surfaces of the two slide rails are provided with oval guide grooves. The tea storage bin is located between the two slide rails, and the driving wheels at both ends are rollingly connected in the corresponding guide grooves.

6. The non-destructive screening device for fresh tea leaves according to claim 5, characterized in that: In the tea storage bin, a plurality of air pressure sensors or gas flow sensors are provided, which are respectively connected to two sides of the tea storage bin and spaced apart along the length direction thereof; There are multiple air suction pumps, which are arranged at intervals along the length direction of the tea accommodating bin.

7. A method for non-destructive screening of fresh tea leaves, characterized in that: This method is implemented based on the non-destructive screening device for fresh tea leaves as described in any one of claims 1 to 6: Make the tea storage bin in a positive state, spread the fresh tea leaves to be screened on the leaf suction partition. The suction pump creates negative pressure inside the tea storage bin below the leaf suction partition, thereby creating suction force on the fresh tea leaves laid on the leaf suction partition through the suction holes; The air pressure sensor or the gas flow sensor detects the air pressure value, and adjusts the operating power of the air suction pump through the controller to ensure that the fresh tea leaves will not fall when the tea storage bin is inverted; The movement mechanism inverts the tea containing bin from the normal state to the inverted state; The tea storage bin stays at the first position, and the controller adjusts and reduces the operating power of the air pump in combination with the measured air pressure value. The smaller fresh tea leaves fall down under their own weight due to the reduced suction force. The tea storage bin stays at the second position, and the controller adjusts and further reduces the operating power of the air pump in combination with the measured air pressure value. The larger fresh tea leaves fall under the action of their own weight due to the reduced suction force, thereby separating the smaller fresh tea leaves from the larger fresh tea leaves.

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