SMT tray detection assembly and parameter calculation method thereof

Abstract

The invention provides an SMT material tray detection assembly and a parameter calculation method thereof, the SMT material tray detection assembly comprises a PCB, a transmitter, a receiver, an isolation blocking structure and an opposite side light absorption blocking structure, the PCB is provided with a plurality of material tray detection ends, and a material tray grid is arranged between every two adjacent material tray detection ends; each tray detection end is provided with a pair of matched emitter and receiver, the emitter and the receiver are respectively arranged at two ends of the same tray detection end at a preset installation included angle theta 1, and the isolation blocking structure is arranged between the emitter and the receiver at the same tray detection end; one side of the charging tray detection end is provided with the opposite-side light absorption blocking structure, and the opposite-side light absorption blocking structure is arranged on one side, close to the mounting surfaces of the emitter and the receiver, of the charging tray detection end. The problem of false triggering can be well avoided, design and implementation are easy, continuous use can be achieved, the actual effect of a product is improved, and the application range of the product is widened.

Description

Technical Field

[0001] The present invention relates to the technical field of material tray detection, in particular to an SMT material tray detection component, and further to a parameter calculation method applied to the SMT material tray detection component. Background Art

[0002] In modern electronic equipment production management, in order to reduce the error rate and improve production efficiency, various manufacturers generally use electronic racks for material management, and link with manufacturing execution system MES (Manufacturing Execution System), warehouse management system WMS (Warehouse Management System) and other production management systems to achieve data interaction, so as to achieve accurate and efficient connection from technical data to production and manufacturing, and realize the material management method of first-in-first-out optimization of material trays, which greatly reduces production and management costs. Among them, the SMT material management methods currently include two types of products: scanning and induction. SMT refers to Surface Mount Technology. Since the induction SMT rack is easier to use and can be monitored in real time during operation, it has become the preferred technical solution for major companies. However, the traditional induction SMT rack adopts the method of shooting for sampling. In actual production, this shooting method may not be able to ensure that the transmitted signal can be reflected or refracted on the surface of the tray and cannot pass through the observation window completely, which will cause false detection of no material; it may also cause false triggering and inability to use continuously due to the presence of materials such as acrylic with high transparency on the tray, which may cause small signal strength differences. Therefore, the existing SMT tray detection solution based on the shooting method has problems such as easy false triggering and inability to be used continuously, which obviously limits its actual use effect and scope of application. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide an SMT tray detection component, which aims to effectively avoid the problems of false triggering and inability to be used continuously based on diffuse reflection and optimized structural design, and improve the actual use effect and application scope of the SMT tray detection component. On this basis, a parameter calculation method for the SMT tray detection component is also provided and applied in a targeted manner.

[0004] To this end, the present invention provides an SMT tray detection component, comprising: a PCB circuit board, a transmitter, a receiver, an isolation blocking structure and an opposite light absorption blocking structure, wherein a plurality of tray detection ends are arranged on the PCB circuit board, and a tray grid is provided between every two adjacent tray detection ends; a pair of matching transmitters and receivers are arranged on each tray detection end, and the transmitter and receiver are respectively arranged at two ends of the same tray detection end at a preset installation angle θ1, wherein the preset installation angle θ1 refers to a preset angle between a mounting surface of the transmitter or receiver and a perpendicular midline of the tray detection end, and the isolation blocking structure is arranged between the transmitter and the receiver of the same tray detection end; the opposite light absorption blocking structure is arranged on one side of the tray detection end, and the opposite light absorption blocking structure is arranged on a side of the tray detection end close to the mounting surface of its transmitter and receiver; The detection process of the SMT tray detection component is as follows: the emission light emitted by the transmitter to the receiver at the same tray detection end is isolated and blocked by the isolation blocking structure; if the emission light emitted by the transmitter to the next tray detection end is absorbed by the corresponding opposite-side light-absorbing blocking structure, the matching receiver cannot receive the emission signal. At this time, it is judged that the current state of the tray grid is that there is no tray; if the matching receiver successfully receives the emission signal, it is judged that the current state of the tray grid is that there is a tray.

[0005] A further improvement of the present invention is that the length of the isolation blocking structure is greater than a first preset multiple of the projection length of the transmitter and the receiver in the horizontal direction, and the first preset multiple is greater than 1.

[0006] A further improvement of the present invention is that the height of the isolation blocking structure is greater than a second preset multiple of the height of any one of the components of the transmitter and the receiver, and the second preset multiple is greater than 1.

[0007] A further improvement of the present invention is that the center points of the transmitter, the receiver and the isolation and blocking structure are located on the same vertical line.

[0008] A further improvement of the present invention is that the receiver is arranged at the bottom end of the tray detection end, and the transmitter is arranged at the top end of the tray detection end.

[0009] A further improvement of the present invention is that the height of the opposite light absorption blocking structure is consistent with the depth of the tray opening and completely blocks the mounting surfaces of the transmitter and receiver at the tray detection end.

[0010] A further improvement of the present invention is that the isolation blocking structure adopts an isolation baffle, and the opposite-side light absorption blocking structure adopts an opposite-side light absorption plate.

[0011] A further improvement of the present invention is that the depth from the signal reflection point of the transmitter to the bottom of the tray opening is greater than half of the center distance between the transmitter and the receiver.

[0012] The present invention also provides a parameter calculation method of an SMT tray detection component, which is applied to the SMT tray detection component as described above and includes the following steps: Step S1, calculating the farthest transmitting distance L3 of the transmitter by the formula L3=L4-L7, and calculating the shortest transmitting distance L8 of the transmitter by the formula L8=L4-L7', wherein L4 represents the width of the tray opening, L7 represents the thickness of the narrowest tray, and L7' represents the thickness of the widest tray; Step S2, by formula (tanθ4)×L5 2 + 2×(L8-L3)×L5 +4×L3×L8×tanθ4= 0 The center distance between the transmitter and the receiver, L5, is calculated, where θ4 refers to the half-decay angle of the transmitter; Step S3, the angle θ3 is calculated by the formula tanθ3= be / ce = L5 / (2×L3), where the angle θ3 refers to the angle between the middle transmission signal of the transmitter lamp bead and the horizontal plane when the emission angle at the strongest radiation position is equal to 0, be refers to the distance between the center point of the transmitter and the midpoint between the transmitter and the receiver, and ce refers to the distance between the far-end reflection point and the midpoint between the transmitter and the receiver; Step S4: using the angle θ3 as the preset installation angle θ1.

[0013] A further improvement of the present invention is that it also includes step S2'. After the center spacing L5 is calculated in step S2, step S2' first determines whether L5 / 2 is less than the depth H3 from the signal reflection point of the transmitter to the bottom of the material tray grid opening. If so, it is determined that the current transmitter meets the requirements and jumps to step S3; if not, it is determined that the current transmitter does not meet the requirements, returns to reselect the transmitter, and jumps to step S2 to calculate the corresponding center spacing L5 after the transmitter is reselected, until L5 / 2 is less than the depth H3 from the signal reflection point of the transmitter to the bottom of the material tray grid opening, then the parameter calculation and selection are completed, and jumps to step S3.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: a plurality of tray detection ends are arranged on the PCB circuit board, and a tray opening is formed between every two adjacent tray detection ends, so as to facilitate independent detection of a plurality of trays at the same time; a pair of matching transmitters and receivers are arranged on each tray detection end, and the transmitter and receiver are respectively arranged at the two ends of the same tray detection end at a preset installation angle θ1, and the isolation blocking structure is arranged between the transmitter and the receiver of the same tray detection end, so that sampling can be achieved based on diffuse reflection on the same side of the tray, and the isolation blocking structure effectively avoids the false triggering caused by the erroneous reception of the emitted light of the transmitter by the receiver; on this basis, an opposite light absorption blocking structure for absorbing light is also arranged on one side of the tray detection end, and the opposite light absorption blocking structure is arranged on the side of the tray detection end close to the mounting surface of its transmitter and receiver.

[0015] Therefore, in the state where there is no material tray, the emitted light of the transmitter is blocked by the isolation blocking structure and is also absorbed by the light-absorbing blocking structure on the opposite side, so that the receiver cannot receive the transmitted signal. At this time, it can be quickly determined that the current state of the material tray grid is that there is no material tray; and in the state where there is a material tray, the emitted light of the transmitter is blocked by the isolation blocking structure, and the transmitted signal on the side close to the material tray will be received by the receiver. Even if the material tray contains materials such as acrylic with high transparency, the problem of false triggering will no longer occur, so that the material tray detection can be accurately and quickly realized, which well avoids the problem of false triggering. It is easy to design and implement, and can be used continuously, effectively improving the actual use effect and application scope of the SMT material tray detection component. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of an embodiment of the present invention; Figure 2 is another structural schematic diagram of an embodiment of the present invention; Figure 3 It is a structural schematic diagram of a material tray according to an embodiment of the present invention; Figure 4 It is a schematic structural diagram of another material tray according to an embodiment of the present invention; Figure 5 It is a structural schematic diagram of a PCB circuit board according to an embodiment of the present invention; Figure 6 It is a schematic diagram of the structure of an embodiment of the present invention during the detection process; Figure 7 It is a schematic diagram of a local structure method of an embodiment of the present invention; Figure 8 yes Figure 7 A is a schematic diagram of the enlarged structure of the middle part; Fig. 9 yes Figure 7 Schematic diagram of the local structure in; Fig.10 It is a simplified schematic diagram of an embodiment of the present invention; Fig.11 is a schematic diagram of a work flow of another embodiment of the present invention; Fig.12 It is a schematic diagram of an optimized workflow of step S2 in another embodiment of the present invention.

[0017] Figure identification: 1-PCB circuit board; 101-tray detection end; 2-transmitter; 201-first emitted light; 202-second emitted light; 3-receiver; 4-isolation blocking structure; 5-opposite side light absorption blocking structure; 6-tray opening; 7-tray; 701-tray detection surface; 702-material observation window; 703-material; 704-tray shaft. DETAILED DESCRIPTION

[0018] In the description of the present invention, if it involves a description of orientation, for example, the orientation or position relationship indicated by "upper", "lower", "front", "back", "left", "right", etc. is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. If a certain technical feature is referred to as "set", "fixed", "connected", or "installed" on another technical feature, it can be directly set, fixed, or connected to the other technical feature, or it can be indirectly set, fixed, connected, or installed on the other technical feature.

[0019] In the description of the present invention, if "several" is involved, it means more than one; if "multiple" is involved, it means more than two; if "greater than", "less than", or "exceed" is involved, it should be understood as not including the number itself; if "above", "below", or "within" is involved, it should be understood as including the number itself. If "first", "second", etc. are involved, they should be understood as being used only to distinguish the names of the same or similar technical features, and should not be understood as implying / indicating the relative importance of the technical features, the number of the technical features, or the order of the technical features.

[0020] The preferred embodiments of the present invention will be further described in detail below in conjunction with the accompanying drawings.

[0021] Before introducing the specific embodiments of the present application, Figure 3 and Figure 4 The two commonly used feed trays shown are explained and illustrated. Figure 3 and Figure 4 In the figure, the structural diagram on the left shows the front view of the material tray 7, and the structural diagram on the right shows the corresponding side view of the material tray 7. In the commonly used material tray 7, it includes Figure 3 The material tray 7 shown has a material observation window 702, and Figure 4 The material tray 7 shown has no material observation window, and the material observation window 702 refers to a window structure for estimating the remaining amount of material through the material tray scale. In both types of material trays 7, the material tray detection surface 701 is used as the detection surface of the transmitter 2 and the receiver 3, and both the front and back sides can be detected by the diffuse reflected light without distinguishing. The material 703 refers to the material wound on the material tray 7, and the material tray shaft 704 is used to realize the rotation of the material tray 7.

[0022] If the traditional cross-beam method is used to realize SMT tray detection, since the cross-beam method needs to be reflected or refracted on the surface of the tray 7 and enter the receiving end on the opposite side, the detection is then performed by judging the ratio received by the receiving end and the threshold. However, in actual applications, there will be various factors that cannot guarantee that the transmitted signal can be reflected or refracted on the surface of the tray, which may easily lead to the failure to completely pass through the material observation window 702, thereby causing false detection of no material. In addition, if the tray 7 has a material 703 made of acrylic or other materials with high transparency, in this application scenario under the cross-beam method, the penetrating emission signal changes very little, and in the case of a small penetration change, not only a high-precision ADC module is required to realize sampling, but even if a high-precision ADC module is used, due to interference from ambient light, this signal with a small change needs to be judged and processed through a threshold, and the setting of the threshold will obviously have the problems of high precision, high difficulty and high cost, and will further increase the probability of false triggering, making the tray detection unable to be used continuously.

[0023] Different from the prior art, the present application adopts diffuse reflection and optimized structural design, which avoids the processing of small signals in principle, because the signal required for reflection is as strong as possible. In the optimized structural design, in the state without a material tray, the transmitted signal has been blocked and absorbed, so there will be no false triggering phenomenon, and there is no need to accurately set the judgment threshold. The overall technical solution is more reasonable and efficient, easy to design and implement, and the continuous service life is greatly improved.

[0024] Specifically, Figures 1 to 12As shown, this embodiment provides an SMT tray detection component, including: a PCB circuit board 1, a transmitter 2, a receiver 3, an isolation blocking structure 4 and an opposite light absorption blocking structure 5, the PCB circuit board 1 is provided with a plurality of tray detection ends 101, and a tray grid 6 is provided between every two adjacent tray detection ends 101; each tray detection end 101 is provided with a pair of matching transmitters 2 and receivers 3, the transmitters 2 and receivers 3 are respectively arranged at the two ends of the same tray detection end 101 at a preset installation angle θ1, and the preset installation angle θ1 refers to the distance between the installation surface of the transmitter 2 or the receiver 3 and the mid-perpendicular line of the tray detection end 101. The preset angle is set, and the isolation blocking structure 4 is set between the transmitter 2 and the receiver 3 of the same tray detection end 101; the opposite light absorption blocking structure 5 is set on one side of the tray detection end 101, and the opposite light absorption blocking structure 5 is set on the side of the tray detection end 101 close to the installation surface of its transmitter 2 and receiver 3; if the emission light of the transmitter 2 is blocked by the isolation blocking structure 4 and absorbed by the opposite light absorption blocking structure 5, the receiver 3 cannot receive the emission signal, at this time, it is judged that the current state of the tray grid 6 is that there is no tray 7; if the receiver 3 successfully receives the emission signal, it is judged that the current state of the tray grid 6 is that there is a tray 7. The installation surface refers to the installation structure at the bottom of the transmitter 2 and the receiver 3.

[0025] In this embodiment, the PCB circuit board 1 is the main control circuit board of the SMT tray detection component, and a plurality of tray detection terminals 101 are provided on the PCB circuit board 1 for realizing diffuse reflection detection of the tray 7. Between every two adjacent tray detection terminals 101 is a tray opening 6, which refers to a window structure for placing the tray 7, so as to realize independent detection of multiple trays 7 at the same time.

[0026] like Figure 1 , Figure 2 as well as Figures 6 to 8As shown, each tray detection end 101 of this embodiment is provided with a pair of matching transmitters 2 and receivers 3, and the transmitters 2 and receivers 3 refer to diffuse reflection transmitters (diffuse reflection devices for emitting light) and diffuse reflection receivers (diffuse reflection devices for receiving light), respectively; that is, the transmitters 2 and receivers 3 are arranged in pairs, and a pair of matching transmitters 2 and receivers 3 are arranged on the same side of the tray 7, and the sampling of the emission signal is realized through the emission and receiving process of diffuse reflection, and the emission signal refers to the signal of the emitted light. The transmitter 2 and receiver 3 are respectively arranged at the two ends of the same tray detection end 101 at a preset installation angle θ1, and the preset installation angle θ1 refers to the preset angle between the installation surface of the transmitter 2 or the receiver 3 and the perpendicular midline of the tray detection end 101. In actual applications, the preset installation angle θ1 is preferably calculated by parameters such as the width of the tray grid 6, the thickness of the tray 7, and the half-decay angle θ4 of the transmitter 2, and can also be obtained by looking up a table. For details, see the description of the parameter calculation method of the SMT tray detection component later. In addition, the isolation blocking structure 4 is arranged between the transmitter 2 and the receiver 3 of the same material tray detection end 101. The isolation blocking structure 4 preferably adopts an isolation baffle to isolate and block the passage of the emitted light. Therefore, this embodiment can realize sampling based on diffuse reflection on the same side of the material tray 7, and effectively avoids the emission light of the transmitter 2 being erroneously received by the receiver 3 and causing false triggering through the isolation blocking structure 4.

[0027] It should be noted that the pair of transmitters 2 and receivers 3 matched / adapted in this embodiment adopt diffuse reflection mode and are arranged on a tray detection end 101, that is, on the same side of the tray 7; and in the corresponding tray grid 6, the opposite light absorption blocking structure 5 is arranged on the other side of the tray 7. In addition, the transmitting end of the transmitter 2 (the end away from the installation surface) is obliquely injected into the tray 7 at a preset installation angle θ1, so that the emitted light can be diffusely reflected on the tray detection surface 701, such as Figure 6 As shown in the optical path defined as the second emission light 202, the second emission light 202 refers to the received emission light. Even if there is a material observation window 702 in the material tray 7 or a transparent material 703, as long as part of the second emission light 202 is successfully received by the receiver 3, it can be accurately judged that the current state of the material tray opening 6 is that there is a material tray 7; therefore, this embodiment does not need to set a very accurate judgment threshold like the prior art adopts the cross-shooting method. Therefore, this embodiment can well avoid the problem of false triggering and can be used continuously; in addition, due to the use of an optimized structural design, it is only necessary to judge whether the emission signal is received, and the required threshold setting range is wide, and it is no longer necessary to perform accurate and difficult threshold setting like the prior art. The overall technical solution is more reasonable, efficient and easy to implement.

[0028] In practical applications, after part of the second emitted light 202 is successfully received by the receiver 3, it can preferably be transmitted to the main control unit MCU after conventional amplification processing through an amplification comparison circuit (such as an integrated circuit such as a multi-stage amplifier). Of course, this process belongs to a preferred implementation method and is not a necessary feature of this embodiment. The emitted light (also called the detection light beam) of the transmitter 2 described in this embodiment can be monochromatic light with a wavelength of 940nm or 860nm, or other wavelength light beams that can be detected. It only needs to ensure that the wavelength of the light beam emitted by the transmitter 2 matches the wavelength that the receiver 3 can receive.

[0029] On this basis, one side of the tray detection end 101 described in the present embodiment is further provided with an opposite light absorption blocking structure 5 for absorbing light. In each tray grid 6, one and only one side is provided with the opposite light absorption blocking structure 5. The opposite light absorption blocking structure 5 preferably adopts an opposite light absorption plate, which is used to absorb the emitted light when there is no tray 7 (no tray 7); the opposite light absorption blocking structure 5 is arranged on one side of the tray detection end 101 close to the mounting surface of its transmitter 2 and receiver 3, so as to ensure that the emitted light of the previous tray detection end 101 is effectively absorbed when there is no tray 7, so as to avoid the problem of part of the emitted light being successfully received when there is no tray 7, effectively avoid the disadvantage of false triggering, and reduce the difficulty and requirements for threshold setting.

[0030] like Figure 6 and Figure 7 As shown, the detection process of the SMT tray detection assembly in this embodiment is as follows: the emission light emitted by the emitter 2 to the receiver 3 of the same tray detection end 101 is isolated and blocked by the isolation blocking structure 4. In the state where there is no tray 7, the emission light emitted by the emitter 2 to the next tray detection end 101 is absorbed by the opposite side light absorption blocking structure 5 (i.e., the corresponding opposite side light absorption blocking structure 5) set at the next tray detection end 101. At this time, the absorbed emission light is Figure 6 In the figure, it is represented as the first emission light 201, so that the receiver 3 cannot receive the emission signal corresponding to the first emission light 201. Therefore, it can quickly and accurately determine that the current state of the tray opening 6 is that there is no tray 7. When there is a tray 7, the emission light of the transmitter 2 directed to the next tray detection end 101 is projected onto the tray detection surface 701 of the tray 7, and then is received by the receiver 3 of the same tray detection end 101 through diffuse reflection, that is, the matching / adapted receiver 3 successfully receives the emission signal and determines that the current state of the tray opening 6 is that there is a tray 7. At this time, the received emission light is Figure 6It is represented as the second emitted light 202. Since the diffuse reflection reception on the same side of the tray 7 is adopted in this embodiment, even if the tray 7 contains material 703 of highly transparent acrylic or other materials, the problem of false triggering will no longer occur, so that the tray 7 can be accurately and quickly detected, which well avoids the problem of false triggering and can be used continuously, effectively improving the actual use effect and application scope of the SMT tray detection component.

[0031] exist Figures 6 to 10 The definitions of various parameters are as follows: L1 is the length of the isolation blocking structure 4; L2 is the length (also called width) of the opposite light absorbing blocking structure 5; L3 is the designed farthest reflection distance, that is, the farthest transmission distance of the transmitter 2; L4 is the width of the tray opening 6; L5 is the center distance between the transmitter 2 and the receiver 3; L6 is the projection length of the transmitter 2 and the receiver 3 in the horizontal plane; L7 is the thickness of the narrowest tray; L7' is the thickness behind the widest tray; L8 is the designed closest reflection distance, that is, the closest transmission distance of the transmitter 2; H1 is the height of the isolation blocking structure 4; H2 is the height of the opposite light absorbing blocking structure 5, which is also used to indicate the depth of the tray opening 6; H3 is the depth from the central transmission signal reflection point to the bottom of the tray opening 6, that is, the depth from the signal reflection point of the transmitter 2 to the bottom of the tray opening 6; θ1 is the preset installation angle between the transmitter 2 and the transceiver 3 and the vertical line; θ2 and θ5 are auxiliary angles; θ3 is the emission angle at the strongest radiation position When the angle is equal to 0, the angle between the central emission signal of the lamp bead and the horizontal plane is the angle between the central emission signal of the lamp bead of transmitter 2 and the horizontal plane when the emission angle at the strongest radiation position is equal to 0; θ4 is the half-decay angle, which can be obtained through the factory data of transmitter 2. It is used to represent the half-decay angle parameter of the angle between the central light intensity of transmitter 2 and the 1 / 2 light intensity line; a is the center point of receiver 3, b is the center point of transmitter 2, c is the far-end reflection point, d is the near-end reflection point, and e is the intersection of the auxiliary line through points d and c and the vertical line through points a and b. Since the distance between the far-end reflection point c and the near-end reflection point d is the same as H3 from the deepest edge of the material tray grid opening 6, and the distance from the material tray grid opening 6 is referenced to the horizontal plane, ce is perpendicular to ab, and θ3 is equal to θ3', θ3' is the auxiliary angle, and θ5=θ3'+θ4=θ3+θ4.

[0032] It is also worth pointing out that Figure 7 and Figure 8As shown, preferably, the length L1 of the isolation blocking structure 4 in this embodiment is greater than the first preset multiple of the projection length L6 of the transmitter 2 and the receiver 3 in the horizontal direction, and the first preset multiple is greater than 1. The first preset multiple refers to a preset multiple threshold value, which can be set and adjusted according to actual conditions and needs. In this embodiment, the first preset multiple defaults to 1.2, so that the emission light from the transmitter 2 to the receiver 3 in the same tray detection end 101 can be completely isolated and blocked in the horizontal direction to avoid the possibility of false triggering. The height H1 of the isolation blocking structure 4 in this embodiment is greater than the second preset multiple of the height of any one of the components of the transmitter 2 and the receiver 3, and the second preset multiple is greater than 1. The height H1 of the isolation blocking structure 4 is related to the height of the components of the transmitter 2 and the receiver 3. The second preset multiple refers to another preset multiple threshold value, which can be set and adjusted according to actual conditions and needs. In this embodiment, the second preset multiple can also default to 1.2, so that the transmitter 2 and the receiver 3 can be completely isolated and blocked in the vertical direction to further avoid the possibility of false triggering.

[0033] In the actual production process, it is necessary to ensure the isolation and blocking effect between the transmitter 2 and the receiver 3 in the same tray detection end 101 in the horizontal and vertical directions. In addition to the length and height dimensions, the installation position will also have an impact. Therefore, the center points of the transmitter 2, the receiver 3 and the isolation and blocking structure 4 in this embodiment are located on the same vertical line, such as Figures 7 and 8 As shown, it can not only ensure the isolation and blocking effects, but also be more conducive to the processing and production of products and improve the production yield of products.

[0034] In this embodiment, a matching / adapted transmitter 2 and receiver 3 need to be set in the same tray detection end 101, that is, the receiver 3 is set at the bottom end of the tray detection end 101, and the transmitter 2 is set at the top end of the tray detection end 101. Figure 2 As shown; the receiver 3 may also be disposed at the top of the tray detection end 101, and the transmitter 2 may be disposed at the bottom of the tray detection end 101, as shown Figure 1 As shown; the above two actual setting methods can be selected according to application requirements or scenarios. Since the receiver 3 is more susceptible to the influence of sunlight, it is preferred that Figure 2As shown, the receiver 3 of this embodiment is arranged at the bottom of the tray detection end 101, and the transmitter 2 is arranged at the top of the tray detection end 101. If the receiver 3 is arranged at the top of the tray detection end 101, the design requirements will be higher. Therefore, in order to meet various application requirements and improve the application range of the product, in other drawings of this embodiment, it is preferred to display and explain that the transmitter 2 is arranged at the bottom of the tray detection end 101 and the receiver 3 is arranged at the top of the tray detection end 101.

[0035] The height H2 of the opposite light absorption blocking structure 5 described in this embodiment is related to the installed structure, that is, it is related to the depth of the tray opening 6, and it is necessary to ensure that its height completely blocks the structural components behind, so that when there is no tray 7, the first emitted light 201 cannot be reflected by other structural components and received by any receiver 3, so as to avoid false triggering. Therefore, preferably, the height H2 of the opposite light absorption blocking structure 5 described in this embodiment is consistent with the depth of the tray opening 6, and completely blocks the installation surface of the transmitter 2 and the receiver 3 of the tray detection end 101.

[0036] It should be noted that if Fig.10 As shown, the depth H3 from the signal reflection point of the transmitter 2 to the bottom of the tray opening 6 in this embodiment is greater than half of the center distance L5 between the transmitter 2 and the receiver 3. The signal reflection point of the transmitter 2 includes a distal reflection point c and a proximal reflection point d. In this embodiment, the depth H3 from the signal reflection point to the bottom of the tray opening 6 needs to be ensured to be greater than half of the center distance L5 between the transmitter 2 and the receiver 3, so as to meet the actual installation requirements of the transmitter 2 and avoid design errors.

[0037] On the basis of providing the SMT tray detection component, another technical problem to be solved in this embodiment is how to calculate the preset installation angle θ1 between the transmitter 2 and the transceiver 3 and the vertical line based on the known parameters, and calculate the center distance L5 between the transmitter 2 and the receiver 3, so as to provide a parameter basis for the production of the SMT tray detection component, facilitate the design and production of products that meet the requirements, and ensure the yield of the product. The known parameters include the width L4 of the tray grid 6, the thickness L7 of the narrowest tray 7 and the thickness L7' of the widest tray, and the half-decay angle θ4 of the transmitter 2.

[0038] like Fig.11 As shown, this embodiment also provides a parameter calculation method of an SMT tray detection component, which is applied to the SMT tray detection component as described above and includes the following steps: Step S1, calculating the farthest transmitting distance L3 of the transmitter 2 by the formula L3=L4-L7, and calculating the closest transmitting distance L8 of the transmitter 2 by the formula L8=L4-L7', wherein L4 represents the width of the tray opening 6, L7 represents the thickness of the narrowest tray 7, and L7' represents the thickness of the widest tray 7; Step S2, by formula (tanθ4) × L5 2 + 2×(L8-L3) ×L5 +4×L3×L8×tanθ4= 0The center distance L5 between transmitter 2 and receiver 3 is calculated, where θ4 refers to the half-decay angle of transmitter 2; Step S3, the angle θ3 is calculated by the formula tanθ3= be / ce = L5 / (2×L3), where the angle θ3 refers to the angle between the middle transmission signal of the lamp bead of the transmitter 2 and the horizontal plane when the emission angle at the strongest radiation position is equal to 0, be refers to the distance between the center point of the transmitter 2 and the midpoint between the transmitter 2 and the receiver 3, and ce refers to the distance between the far-end reflection point and the midpoint between the transmitter 2 and the receiver 3; Step S4: using the angle θ3 as the preset installation angle θ1.

[0039] In this embodiment, if Fig.10 As shown, θ1+θ2 is the 90° angle between the vertical line and the horizontal plane, that is, 90°=θ1+θ2. θ2+θ3 is the 90° angle between the central signal line of transmitter 2 and the mounting surface of transmitter 2, that is, 90°=θ2+θ3. Therefore, θ1=θ3 =θ3', therefore, it is only necessary to calculate the angle between the central transmission signal of transmitter 2 and the horizontal plane, which is the preset installation angle θ1, also known as the lamp bead installation angle.

[0040] In order to ensure the detection stability of the material tray 7, the present embodiment also needs to consider a certain margin. The depth H3 from the signal reflection point of the transmitter 2 to the bottom of the material tray opening 6 is selected by default as half of the height H0 from the bottom of the material observation window 702 to the bottom of the material tray 7, that is, the default value H3=H0 / 2, to ensure that even if the material tray 7 is provided with a material observation window 702, the reflection path of the central light path will not be affected by the position of the material tray 7.

[0041] like Fig.10 As shown, the length of ce is equal to L3, the length of de is equal to L8, and the length of be is equal to L5 / 2. That is, tanθ3' = be / ce = L5 / (2×L3), tanθ5 = be / de = L5 / (2×L8).

[0042] Since θ5 =θ3+θ4 =θ3' +θ4, substituting it into the formula tanθ5 = be / de = L5 / (2×L8), we can get tan(θ3' +θ4) = L5 / (2×L8). According to the tangent formula tan(θ3'+θ4) = (tanθ3' + tanθ4) / (1 - tanθ3' tanθ4), substituting the formula tanθ3' = be / ce = L5 / (2×L3) into the formula tan(θ3'+θ4) =(tanθ3' + tanθ4) / (1-tanθ3' tanθ4), we can get (L5 / (2×L3)+tanθ4) / (1-L5 / (2×L3)×tanθ4) = L5 / (2×L8). After simplifying this formula, we can get (tanθ4) ×L5 2 + 2×(L8-L3)×L5 +4×L3×L8×tanθ4= 0.

[0043] Therefore, based on the known width L4 of the tray opening 6, the thickness L7 of the narrowest tray 7, the thickness L7' of the widest tray and the half-decay angle θ4 of the transmitter 2, the center distance L5 between the transmitter 2 and the receiver 3 can be calculated by solving a quadratic equation, and then the angle θ3 can be calculated by the formula tanθ3= tanθ3' = be / ce = L5 / (2×L3), and this angle θ3 is used as the preset installation angle θ1.

[0044] It should be noted that if Fig.12 As shown, this embodiment also preferably includes step S2', wherein after the center spacing L5 is calculated in step S2, step S2' first determines whether L5 / 2 is less than the depth H3 from the signal reflection point of the transmitter 2 to the bottom of the tray grid 6. If so, it is determined that the current transmitter 2 meets the requirements, and the process jumps to step S3; if not, it is determined that the current transmitter 2 does not meet the requirements, and the transmitter 2 is reselected, and the process jumps to step S2 to calculate the corresponding center spacing L5 after the transmitter 2 is reselected, until L5 / 2 is less than the depth H3 from the signal reflection point of the transmitter 2 to the bottom of the tray grid 6, then the calculation and selection of parameters are completed, and the process jumps to step S3. The parameters include the center spacing L5 between the transmitter 2 and the receiver 3, and the preset installation angle θ1, so as to accurately find diffuse reflection components that match and meet production requirements, and ensure the production yield of the product.

[0045] Of course, in actual applications, the present embodiment can also calculate in advance the corresponding center spacing L5 of the transmitter 2 and the receiver 3, and the preset installation angle θ1 according to the commonly used width L4 of the tray opening 6, the thickness L7 of the narrowest tray 7, the thickness L7' of the widest tray, and the half-decay angle θ4 of the transmitter 2, and establish an index table with a corresponding relationship. Then, in actual production, the index table can be queried through the known parameters such as the width of the tray opening 6, the thickness of the tray 7 (including the thickness L7 of the narrowest tray 7 and the thickness L7' of the widest tray), and the half-decay angle θ4 of the transmitter 2, so as to quickly obtain the corresponding center spacing L5 and the preset installation angle θ1, so as to improve the production efficiency of the product.

[0046] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. An SMT tray detection component, characterized in that: include: PCB circuit board, transmitter, receiver, isolation blocking structure and opposite light absorption blocking structure, the PCB circuit board is provided with a plurality of tray detection ends, and a tray grid is provided between every two adjacent tray detection ends; each tray detection end is provided with a pair of matching transmitters and receivers, the transmitter and receiver are respectively provided at the two ends of the same tray detection end at a preset installation angle θ1, the preset installation angle θ1 refers to the preset angle between the installation surface of the transmitter or receiver and the mid-vertical line of the tray detection end, and the isolation blocking structure is provided between the transmitter and the receiver of the same tray detection end; the opposite light absorption blocking structure is provided on one side of the tray detection end, and the opposite light absorption blocking structure is provided on the side of the tray detection end close to the installation surface of its transmitter and receiver; The detection process of the SMT tray detection component is as follows: the emitted light emitted by the transmitter to the receiver at the same tray detection end is isolated and blocked by the isolation blocking structure; If the emission light from the transmitter to the next tray detection end is absorbed by the corresponding light-absorbing blocking structure on the opposite side, the matching receiver cannot receive the emission signal. At this time, it is judged that the current tray grid state is no tray; If the matching receiver successfully receives the transmission signal, it is determined that the current state of the material tray opening is that there is a material tray.

2. The SMT tray detection component according to claim 1, characterized in that: The length of the isolation blocking structure is greater than a first preset multiple of the projection length of the transmitter and the receiver in the horizontal direction, and the first preset multiple is greater than 1.

3. The SMT tray detection component according to claim 2, characterized in that: The height of the isolation blocking structure is greater than a second preset multiple of the height of any one of the transmitter and the receiver, and the second preset multiple is greater than 1.

4. The SMT tray detection component according to claim 2, characterized in that: The center points of the transmitter, the receiver and the isolation barrier structure are located on the same vertical line.

5. The SMT tray detection component according to any one of claims 1 to 4, characterized in that: The receiver is arranged at the bottom end of the tray detection end, and the transmitter is arranged at the top end of the tray detection end.

6. The SMT tray detection component according to any one of claims 1 to 4, characterized in that: The height of the opposite light absorption blocking structure is consistent with the depth of the tray opening, and completely blocks the installation surfaces of the transmitter and the receiver at the tray detection end.

7. The SMT tray detection assembly according to any one of claims 1 to 4, characterized in that: The isolation blocking structure adopts an isolation baffle, and the opposite-side light absorption blocking structure adopts an opposite-side light absorption plate.

8. The SMT tray detection component according to any one of claims 1 to 4, characterized in that: The depth from the signal reflection point of the transmitter to the bottom of the tray opening is greater than half of the center distance between the transmitter and the receiver.

9. A parameter calculation method for an SMT tray detection component, characterized in that: The method is applied to the SMT tray detection component as claimed in any one of claims 1 to 8, and comprises the following steps: Step S1, calculating the farthest transmitting distance L3 of the transmitter by the formula L3=L4-L7, and calculating the shortest transmitting distance L8 of the transmitter by the formula L8=L4-L7', wherein L4 represents the width of the tray opening, L7 represents the thickness of the narrowest tray, and L7' represents the thickness of the widest tray; Step S2, by formula (tanθ4)×L5 2 + 2×(L8-L3) ×L5 +4×L3×L8×tanθ4= 0The center distance between the transmitter and the receiver is calculated to be L5, where θ4 refers to the half-decay angle of the transmitter; Step S3, the angle θ3 is calculated by the formula tanθ3= be / ce = L5 / (2×L3), where the angle θ3 refers to the angle between the middle transmission signal of the transmitter lamp bead and the horizontal plane when the emission angle at the strongest radiation position is equal to 0, be refers to the distance between the center point of the transmitter and the midpoint between the transmitter and the receiver, and ce refers to the distance between the far-end reflection point and the midpoint between the transmitter and the receiver; Step S4: using the angle θ3 as the preset installation angle θ1.

10. The parameter calculation method of the SMT tray detection component according to claim 9, characterized in that: The method further includes step S2'. After the center spacing L5 is calculated in step S2, step S2' first determines whether L5 / 2 is less than the depth H3 from the signal reflection point of the transmitter to the bottom of the material tray grid opening. If so, it is determined that the current transmitter meets the requirements, and the process jumps to step S3; if not, it is determined that the current transmitter does not meet the requirements, and the process returns to reselect the transmitter, and the process jumps to step S2 to calculate the corresponding center spacing L5 after the transmitter is reselected, until L5 / 2 is less than the depth H3 from the signal reflection point of the transmitter to the bottom of the material tray grid opening, the parameter calculation and selection are completed, and the process jumps to step S3.

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