Device for detecting position of jig in vacuum furnace and vacuum furnace
By installing a through-beam sensor and optical path channel outside the vacuum furnace, combined with nitrogen micro-positive pressure, the problems of fixture position detection accuracy and sensor lifespan were solved, improving the processing yield and sealing performance of the vacuum furnace.
Patent Information
- Application Number
- CN202520012050.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-03
- Publication Date
- 2025-11-25
- Estimated Expiration
- 2035-01-03
AI Technical Summary
In existing vacuum furnaces, when conveying the fixture, the fixture may become skewed, making it impossible to accurately deliver it to the designated position. This could damage the product, affect the processing yield, and the sensor is susceptible to damage from high temperatures, which could shorten its lifespan.
The position of the fixture is detected by a through-beam sensor located outside the furnace. The sensor detects light through the optical path channel and the light-transmitting part. The light path is prevented from being blocked by nitrogen micro-positive pressure to maintain the airtightness. An adjustment structure is used to ensure that the sensor is accurately positioned.
It enables precise detection of fixture position, avoids high temperature damage to sensors, improves processing yield, and maintains furnace sealing and stable oxygen concentration.
Smart Images
Figure CN223596797U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of vacuum furnace technology, and in particular to a device for detecting the position of fixtures inside a vacuum furnace and a vacuum furnace. Background Technology
[0002] Currently, most printed circuit board (PCB) soldering relies on vacuum furnaces. Products are fed into a high-temperature vacuum furnace, where the solder melts and bonds the PCB. The vacuum furnace consists of a lower chamber and an upper chamber. The upper chamber can be opened and closed; when the upper chamber is closed over the lower chamber, a high-temperature vacuum zone is formed between them. Products are transported through a conveyor system within the vacuum furnace, typically placed on fixtures. However, if the conveyor system is unstable, causing the fixture to tilt and fail to reach the designated center position within the vacuum zone, there is a risk that the upper chamber may crush the product when it closes. Therefore, precise fixture positioning is crucial to effectively improve product yield. Utility Model Content
[0003] To overcome the above-mentioned shortcomings, the purpose of this utility model is to provide a detection device for the position of the fixture inside a vacuum furnace and a vacuum furnace, which can detect the position of the fixture inside the vacuum furnace without damaging the sealing performance of the vacuum furnace.
[0004] To achieve the above objectives, the technical solution adopted by this utility model is: a detection device for the position of a fixture inside a vacuum furnace, the vacuum furnace including a lower shell, an upper shell hinged to the lower shell to cover its opening, the detection device including a detection component, the detection component including:
[0005] A through-beam sensor, comprising a transmitter and a receiver, wherein the transmitter and the receiver are respectively fixed on the outer surfaces of two side plates in the width direction of the lower shell, and a detection beam is formed between the transmitter and the receiver;
[0006] An optical path channel is provided on the lower shell, and the detection light can pass through the optical path channel.
[0007] A light-transmitting part is fixed to the end of the optical path channel near the transmitting end or the receiving end. The light-transmitting part closes the optical path channel and allows the detection light to pass through.
[0008] The beneficial effects of this utility model are as follows:
[0009] Adding a beam sensor can effectively detect whether the fixture has reached a certain position by detecting light, that is, the position of the fixture can be detected;
[0010] The through-beam sensor is located outside the lower shell, that is, outside the furnace, which can effectively avoid the impact of the high temperature generated in the furnace on the life of the through-beam sensor, and at the same time avoid the impact of high and low temperature deformation of the furnace on the detection light.
[0011] The matching light-transmitting part does not affect the passage of detection light, and at the same time achieves the effect of sealing the furnace, so that there is no leakage in the furnace and it does not affect the oxygen concentration in the furnace.
[0012] Furthermore, the optical path channel is connected to a vent located near the light-transmitting part, and this vent is used to introduce nitrogen gas. Injecting nitrogen into the optical path channel through the vent maintains a slight positive pressure within the channel, effectively preventing blockage of the optical path channel or contamination of the light-transmitting part caused by flux buildup in the furnace atmosphere, thus avoiding false detection due to light malfunction. Simultaneously, an appropriate amount of nitrogen also has a positive effect on improving the local oxygen concentration.
[0013] Furthermore, a fixing block is fixed on the outer surface of the two side plates, and the fixing block and the side plate together form the light path channel; the light-transmitting part is pressed against the outer surface of the fixing block away from the lower shell body by an annular pressing block.
[0014] Furthermore, the vent is located on the fixed block, which makes it easy to process the vent and reduces the difficulty of processing.
[0015] Furthermore, sealing elements are provided between the light-transmitting portion and both the fixing block and the annular pressure block. The two sealing elements provide a double seal, improving the airtightness of the optical path and preventing gas leakage within the optical path.
[0016] Furthermore, the detection components are provided in two sets, which are spaced apart along the length of the lower shell. When the detection light of both sets of detection components is not blocked, the upper shell is pressed against the lower shell under the drive of the flipping drive.
[0017] Furthermore, the detection component also includes a support plate and a connecting frame corresponding to the transmitter and the receiver respectively. The support plate is used to fix the transmitter or the receiver. The support plate is fixed to the lower shell through the connecting frame. The connecting frame can adjust the position of the support plate.
[0018] Furthermore, the connecting frame includes a horizontal plate and a vertical plate. The vertical plate has a first oblong hole extending vertically. The support plate is fixedly connected to the vertical plate via a first locking member passing through the first oblong hole. The height of the transmitter or receiver is adjusted by the cooperation of the first locking member and the first oblong hole. The horizontal plate has a second oblong hole extending along the length of the lower shell. The horizontal plate is fixedly connected to the lower shell via a second locking member passing through the second oblong hole. The position of the transmitter or receiver in the length direction is adjusted by the cooperation of the second oblong hole and the second locking member.
[0019] Furthermore, the detection light beam and the optical path channel are coaxial.
[0020] This utility model also discloses a vacuum furnace that uses the above-mentioned detection device. Attached Figure Description
[0021] Figure 1 This is a three-dimensional structural diagram of the testing device fixed on the side plate in an embodiment of the present invention;
[0022] Figure 2 for Figure 1 Enlarged view of point A in the middle;
[0023] Figure 3 This is a cross-sectional view of the vacuum furnace along the width direction in an embodiment of this utility model;
[0024] Figure 4 for Figure 3 Enlarged view of section B in the middle.
[0025] In the picture:
[0026] 100. Lower shell; 101. Side plate; 200. Fixture; 300. Upper shell; 400. Furnace chamber;
[0027] 1a. First detection component; 1b. Second detection component;
[0028] 1. Through-beam sensor; 11. Transmitter; 12. Receiver; 13. Light detection;
[0029] 2. Optical path channel;
[0030] 3. Light-transmitting part;
[0031] 4. Fixing block; 41. Vent;
[0032] 5. Annular pressing block;
[0033] 6. Sealing components;
[0034] 71. Support plate; 72. Vertical plate; 721. First oblong hole; 73. Horizontal plate; 731. Second oblong hole. Detailed Implementation
[0035] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the scope of protection of the present invention.
[0036] In the description of this application, the arrow X in all the figures points in the length direction, the arrow Y points in the width direction, and the arrow Z points in the vertical direction.
[0037] This utility model discloses a detection device for the position of a fixture inside a vacuum furnace. The detection device is used to detect the position of the fixture 200 inside the vacuum furnace. A conveying device is installed inside the vacuum furnace, and the fixture 200 is placed on the conveying device for transport. The conveying device transports the fixture 200 along the length of the vacuum furnace. The conveying device only needs to achieve linear transport; further details are omitted here. See appendix. Figure 1 and attached Figure 3 As shown, the vacuum furnace includes a lower shell 100 with an opening at the top, and an upper shell 300 is hinged to the opening of the lower shell 100. The upper shell 300 can be flipped by a flipping drive to open and close the opening. When the upper shell 300 covers and rests on the lower shell 100, a furnace cavity is defined between the two, and the product on the fixture 200 is processed in the furnace cavity.
[0038] The detection device is mounted on the lower shell 100 and is used to detect the position of the fixture 200 inside the vacuum furnace. The lower shell 100 includes two side plates 101 spaced apart along the width direction. Both side plates 101 are hollow plates, and insulation cotton is installed inside the side plates 101 to improve the insulation effect and prevent temperature loss inside the furnace chamber 400.
[0039] A lower shell 100 is hinged to an upper shell 300 that can cover its opening, and participates in the attachment. Figure 2 and attached Figure 3 As shown, the detection device includes a detection component, which includes a through-beam sensor 1, an optical path channel 2, and a light-transmitting part 3.
[0040] The through-beam sensor 1 includes a transmitter 11 and a receiver 12, which are respectively fixed to the outer surface of the side plate 101. A detection light beam 13 is formed between the transmitter 11 and the receiver 12. The transmitter 11 emits the detection light beam 13, and the receiver 12 receives the detection light beam 13. When the fixture 200 blocks the detection light beam 13, the receiver 12 cannot receive the detection light beam 13; otherwise, it can receive it. The through-beam sensor 1 is located outside the lower shell 100, that is, outside the furnace 400, which can effectively avoid the impact of the high temperature generated in the furnace 400 on the lifespan of the through-beam sensor 1, and at the same time, avoid the impact of high and low temperature deformation of the furnace 400 on the detection light beam 13.
[0041] However, in order for the detection light 13 to detect the fixture 200 inside the furnace 400, the light path channel 2 is opened on the lower shell 100. The position of the light path channel 2 corresponds to the position of the detection light 13, and the detection light 13 can pass through the light path channel 2.
[0042] The furnace 400 requires a sealed environment for product processing, therefore see Appendix Figure 4 As shown, a light-transmitting part 3 is provided, which is fixed to the end of the optical path channel 2 near the transmitting end 11 or the receiving end 12. The light-transmitting part 3 closes the optical path channel 2 but allows the detection light beam 13 to pass through. At this time, the outer light-transmitting part 3 does not affect the passage of the detection light beam 13, and at the same time achieves the effect of sealing the furnace chamber 400, ensuring no leakage in the furnace chamber 400 and not affecting the oxygen concentration inside the furnace chamber 400. The optical path channel 2 is connected to the furnace chamber 400 at this time, but is isolated from the external space of the vacuum furnace.
[0043] The light-transmitting part 3 is made of transparent glass or high-temperature resistant transparent plastic.
[0044] In one embodiment, see Appendix Figure 2 and attached Figure 4 As shown, the optical path channel 2 is connected to a vent 41, which is located near the light-transmitting part 3. The vent is used to introduce nitrogen gas. Injecting nitrogen into the optical path channel 2 through the vent maintains a slight positive pressure within the channel, effectively preventing blockage of the optical path channel 2 or contamination of the light-transmitting part 3 caused by flux buildup in the furnace atmosphere 400, thus avoiding misjudgments due to the detection light beam 13. Simultaneously, an appropriate amount of nitrogen also has a positive effect on improving the local oxygen concentration.
[0045] In one embodiment, the detection light 13 and the optical path channel 2 are coaxial, and the diameter of the optical path channel 2 is larger than the diameter of the detection light 13. In this case, the optical path channel 2 will not block the detection light 13, allowing the detection light 13 to pass through easily. The detection light 13 and the optical path channel 2 may also be non-coaxial, but their central axes are parallel.
[0046] See appendix Figure 1 and attached Figure 2As shown, the lower shell 100 includes two side plates 101. A fixing block 4 is fixed to the outer surfaces of the two side plates 101, which are far apart from each other. The fixing block 4 and the side plates 101 share the optical path channel 2. The light-transmitting portion 3 is pressed against the outer surface of the fixing block 4, which is far from the body of the lower shell 100, by an annular pressing block 5. The fixing block 4 is fixed to the side plates 101 by bolts, and the annular pressing block 5 is fixed to the fixing block 4 by bolts. The vent is located on the fixing block 4. Adding the fixing block 4 to the side plates 101 facilitates the opening of the vent; the fixing block 4 forms a T-junction, which is easy to process.
[0047] In one embodiment, the fixing block 4 may be omitted, and the light-transmitting part 3 may be pressed directly onto the side plate 101 by the annular pressing block 5. However, in this case, a vent 41 that is directly connected to the light path channel 2 needs to be opened on the side plate 101.
[0048] In one embodiment, a sealing element 6 is provided between the light-transmitting part 3 and both the fixing block 4 and the annular pressure block 5. The sealing element 6 is a sealing ring. The provision of two sealing elements 6 achieves double sealing, improves the sealing performance of the optical path channel 2, and prevents gas leakage within the optical path channel 2.
[0049] See appendix Figure 1 As shown, the detection components are provided in two sets, which are spaced apart along the length of the lower shell 100. The two sets of detection components are the first detection component 1a and the second detection component 1b, and the two sets of detection components have the same structure.
[0050] When neither of the detection rays 13 of the two sets of detection components is blocked, the upper shell 300 is pressed against the lower shell 100 under the drive of the driving component. The distance between the two detection rays 13 is greater than the length of a fixture 200. When the fixture 200 moves to the designated position, it should be located between the two detection rays 13. That is, if either of the two detection rays 13 is blocked, the position of the fixture 200 is abnormal. At this time, the upper shell 300 covers the lower shell 100, which will cause product abnormality. Therefore, two detection components are set to detect the position of the fixture 200 in the direction of movement.
[0051] In one embodiment, the position of the through-beam sensor 1 is adjustable. During installation, the sensor 1 is adjusted to a suitable position to ensure that the through-beam end and the receiver end 12 can be connected. Therefore, the detection assembly also includes a support plate 71 and a connecting frame corresponding to the transmitter end 11 and the receiver end 12 respectively. The support plate 71 is used to fix the transmitter end 11 or the receiver end 12. The support plate 71 is fixed to the lower shell 100 through the connecting frame, and the connecting frame can adjust the position of the support plate 71.
[0052] See appendix Figure 2As shown, the connecting frame includes a horizontal plate 73 and a vertical plate 72, which are L-shaped. The vertical plate 72 has a first oblong hole 721 extending vertically. The support plate 71 is fixedly connected to the vertical plate 72 by a first locking member passing through the first oblong hole 721. The first locking member is a bolt, and the height position of the transmitter 11 or receiver 12 is adjusted by the cooperation of the first locking member and the first oblong hole 721. The horizontal plate 73 has a second oblong hole 731 extending along the length of the lower shell 100. The horizontal plate 73 is fixedly connected to the lower shell 100 by a second locking member passing through the second oblong hole 731. The second locking member is also a bolt, and the position of the transmitter 11 or receiver 12 in the length direction is adjusted by the cooperation of the second oblong hole 731 and the second locking member.
[0053] In one embodiment, this utility model discloses a vacuum furnace employing the aforementioned detection device. By adding the detection device, the position of the fixture 200 can be detected in real time. When the detection light rays 13 of both sets of detection components are not blocked, the upper shell 300 is pressed against the lower shell 100 under the drive of the driving component, effectively preventing damage to the product caused by the upper shell 300 when the fixture 200 is in an abnormal position. Simultaneously, the through-beam sensor 1 is located outside the furnace chamber 400, satisfying position detection while preventing damage to the through-beam sensor 1 due to high temperature, thus not affecting the service life of the through-beam sensor 1.
[0054] The above embodiments are only for illustrating the technical concept and features of this utility model. Their purpose is to enable those skilled in the art to understand the content of this utility model and implement it. They cannot be used to limit the protection scope of this utility model. All equivalent changes or modifications made in accordance with the spirit and essence of this utility model should be covered within the protection scope of this utility model.
Claims
1. A device for detecting the position of a jig in a vacuum furnace, said vacuum furnace comprising a lower shell to which a upper shell is hinged so as to be able to close the opening thereof, characterized in that: The detection device comprises a detection assembly, which comprises: a pair of light beams sensors, each of which comprises a transmitting end and a receiving end, the transmitting end and the receiving end are fixed on the outer surfaces of two side plates of the lower shell in the width direction, and the detection light beams are formed between the transmitting end and the receiving end; a light path channel, which is arranged on the lower shell and through which the detection light beams can pass; a light-transmitting part, which is fixed on the end of the light path channel close to the transmitting end or the receiving end, and closes the light path channel and allows the detection light beams to pass through.
2. The apparatus for detecting the position of a fixture within a vacuum furnace as defined in claim 1, wherein: The light path channel is communicated with a vent, which is arranged close to the light-transmitting part, and the vent is used for introducing nitrogen.
3. The apparatus for detecting the position of a fixture within a vacuum furnace of claim 2, wherein: The outer surfaces of the two side plates are fixed with fixing blocks, and the light path channel is arranged on the fixing blocks and the side plates; The light-transmitting part is pressed on the outer surfaces of the fixing blocks away from the lower shell body by an annular pressing block.
4. The apparatus for detecting the position of a fixture within a vacuum furnace of claim 3, wherein: The vent is arranged on the fixing block.
5. The apparatus for detecting the position of a fixture within a vacuum furnace as defined in claim 3, wherein: Sealing members are arranged between the light-transmitting part and the fixing blocks and the annular pressing block.
6. The apparatus for detecting the position of a fixture in a vacuum furnace according to any one of claims 1-5, wherein: The detection assembly is provided with two groups, and the two groups of detection assemblies are arranged at intervals along the length direction of the lower shell, and when the detection light beams of the two groups of detection assemblies are not blocked, the upper shell is pressed on the lower shell under the driving of the overturning driving member.
7. The apparatus for detecting the position of a fixture within a vacuum furnace of claim 1, wherein: The detection assembly further comprises a support plate and a connecting frame corresponding to the transmitting end and the receiving end one by one, the support plate is used for fixing the transmitting end or the receiving end, and the support plate is fixed with the lower shell through the connecting frame, and the connecting frame can adjust the position of the support plate.
8. The apparatus for detecting the position of a fixture within a vacuum furnace of claim 7, wherein: The connecting frame comprises a horizontal plate and a vertical plate, the vertical plate is provided with a first waist-shaped hole extending in the vertical direction, the support plate is fixed and connected with the vertical plate through a first locking member penetrating through the first waist-shaped hole, and the horizontal plate is provided with a second waist-shaped hole extending in the length direction of the lower shell, and the horizontal plate is fixed and connected with the lower shell through a second locking member penetrating through the second waist-shaped hole.
9. The apparatus for detecting the position of a fixture within a vacuum furnace of claim 1, wherein: The detection light beams and the light path channel are coaxial.
10. A vacuum furnace characterized by: The detection device of any one of claims 1-9 is adopted.