A positioning fixture for short working distance detection

Abstract

The present invention discloses a positioning fixture for short working distance detection, including a mother fixture, a sub-fixture, a plurality of locking screws, a plurality of top screws and a plurality of component pressing blocks, the mother fixture is a frame structure, the sub-fixture includes a component positioning frame and a component limiting frame, the component limiting frame is fixedly connected to the front surface of the component positioning frame, and a component limiting plate is fixed on the top and bottom ends of the inner wall of the component limiting frame. When clamping, the component limiting frame passes through the inner ring of the mother fixture; a plurality of locking screws pass through the component positioning frame and are threadedly connected to the threaded holes of the mother fixture, and a plurality of top screws pass through the component positioning frame and abut against the rear surface of the mother fixture; when clamping, the component is placed in the inner ring of the sub-fixture and the front surface of the component abuts against the rear surfaces of two component limiting plates, and a plurality of component pressing blocks press the rear surface of the component to position the component in the sub-fixture. The present invention can realize a short working distance and accurately position the posture of the component.

Description

Technical Field

[0001] The invention relates to the technical field of positioning fixtures, in particular to a positioning fixture used for short working distance detection. Background Art

[0002] Inspection is a crucial part of the manufacturing process and product application, and determines whether the product quality meets the demand. When high-precision inspection is used, when the size of the defect is in the micron and nanometer levels, many inspection methods have strict requirements on the distance and angle between the inspection tool and the surface of the component to be inspected. For example, when a high-power objective lens (50X-100X) is used, the working distance is generally only 0.5mm-1mm. At this working distance, while achieving stable clamping of the component, adjusting the surface of the component to be perpendicular to the axis of the objective lens becomes a very difficult problem to solve. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a positioning fixture for short working distance detection, which can achieve a short working distance and accurately position the posture (pitch, yaw) of a component.

[0004] The technical solution of the present invention is:

[0005] A positioning fixture for short working distance detection, comprising a mother fixture, a sub-fixture, a plurality of locking screws, a plurality of top screws, a plurality of component pressing blocks and an auxiliary positioning plate;

[0006] The mother fixture is a frame structure, and the sub-fixture is a double-layer frame structure composed of a component positioning frame and a component limiting frame. The inner circles of the component positioning frame and the component limiting frame overlap each other, and the outer circle of the component positioning frame is located at the outer periphery of the outer circle of the component limiting frame. The component limiting frame is fixedly connected to the front surface of the component positioning frame.

[0007] Two component limiting plates are fixed on the component limiting frame, the two component limiting plates are parallel to the frame of the component limiting frame and are respectively fixed on the top and bottom ends of the inner wall of the component limiting frame, the thickness of each component limiting plate is less than the thickness of the component limiting frame, the front surfaces of the two component limiting plates and the front surface of the component limiting frame are located in the same plane, and the thickness of the component limiting frame minus the thickness of the component limiting plates is greater than the thickness of the mother fixture;

[0008] The shape and size of the outer ring of the component positioning frame is larger than the shape and size of the inner ring of the female fixture. When clamping, the component limiting frame passes through the inner ring of the female fixture, and the component positioning frame is located behind the female fixture;

[0009] The multiple locking screws pass through the through holes of the component positioning frame and are threadedly connected to the threaded holes of the female clamp, and the multiple top screws pass through the threaded holes of the component positioning frame and abut against the rear surface of the female clamp;

[0010] When clamping, the component is placed in the inner circle where the component positioning frame and the component limiting frame of the sub-clamp overlap, and the front surface of the component is against the rear surfaces of the two component limiting plates. When clamping, the multiple component pressing blocks press the rear surface of the component to position the component in the sub-clamp;

[0011] The rear surface of the auxiliary positioning plate faces the front surface of the mother clamp, and outer convex strips are arranged on the rear surface of the auxiliary positioning plate and adjacent to its two ends, and corresponding inner convex strips are arranged on the rear surface of the auxiliary positioning plate and on the inner side of each outer convex strip, that is, the two inner convex strips are located between the two outer convex strips, and a groove structure is formed between each outer convex strip and the corresponding inner convex strip. The thickness of the outer convex strip and the inner convex strip are equal, that is, the rear surfaces of the outer convex strip and the inner convex strip are located in the same plane. When the components are assembled, the rear surfaces of the two outer convex strips on the auxiliary positioning plate are respectively close to the front surface of the mother clamp, that is, the positioning surface of the mother clamp, and the vertical frame portion of the component limit frame extends into the corresponding groove of the auxiliary positioning plate, and the rear surfaces of the two inner convex strips are in contact with the front surface of the component.

[0012] There are four locking screws, and the component positioning frame is provided with four through holes, which are evenly distributed along the frame of the component positioning frame. The four locking screws respectively pass through the corresponding through holes of the component positioning frame and are threadedly connected to the threaded holes of the female clamp.

[0013] The component pressing block is an L-shaped pressing block structure. The horizontal part of each component pressing block extends into the overlapping inner circle of the fixture component positioning frame and the component limiting frame to press the rear surface of the component, and the vertical part of each component pressing block is close to the rear surface of the component positioning frame.

[0014] The component positioning frame, the component limiting frame and the two component limiting plates of the sub-clamp are an integrated molding structure.

[0015] Advantages of the present invention:

[0016] After the clamping of the component is completed, the mother-and-child clamps are used as a whole, and the front surface of the component is in contact with the front surface of the mother clamp in the same plane. The mother-and-child clamps are loaded into the equipment as a whole, and the loading of the component can be completed only by positioning with the front surface of the mother clamp; after the conversion of the surface to be inspected, i.e., the front surface, and the positioning surface, i.e., the front surface, of the component, the working distance of the detection tool only needs to be greater than the thickness of the component limit plate of the child clamp for detection, and the edge of the component can be detected; the positioning surface of the child clamp of the present invention, i.e., the rear surface of the component limit plate, does not require high-precision processing and deformation is allowed, so the thickness of the component limit plate can be designed to be very thin. For example, when using a high-power objective lens for observation, if the working distance is 0.5mm, the thickness of the component limit plate can be designed to be 0.3mm-0.4mm, which can meet the detection requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the structure of the present invention for component clamping.

[0018] Figure 2 It is an exploded view of the present invention.

[0019] Figure 3 It is a schematic diagram of the structure of the sub-fixture clamping components.

[0020] Figure 4 It is a transverse cross-sectional view of the sub-fixture clamping element.

[0021] Figure 5 It is a longitudinal cross-sectional view of the sub-fixture clamping element.

[0022] Figure 6 It is a structural schematic diagram of the mother fixture and the auxiliary positioning plate.

[0023] Figure 7 This is a cross-sectional view after the sub-clamp is installed in the main clamp and the adjustment is completed. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] See Figure 1-Figure 7 , a positioning fixture for short working distance detection, including a mother fixture 1, a sub-clamp 2, four locking screws 3, three top screws 4, four component pressing blocks 5 and an auxiliary positioning plate 7;

[0026] The mother fixture 1 is a rectangular frame structure, and the sub-fixture 2 is a double-layer rectangular frame structure composed of a component positioning frame 21 and a component limiting frame 22. The inner circles of the component positioning frame 21 and the component limiting frame 22 overlap each other, and the outer circle of the component positioning frame 21 is located at the outer periphery of the outer circle of the component limiting frame 22. The component limiting frame 22 is fixedly connected to the front surface of the component positioning frame 21;

[0027] A vertically arranged component limiting plate 23 is fixed to the upper and lower horizontal surfaces of the inner wall of the component limiting frame 22. The thickness of each component limiting plate 23 is smaller than the thickness of the component limiting frame 22. The front surfaces of the two component limiting plates 23 and the front surface of the component limiting frame 22 are located in the same plane, and the thickness of the component limiting frame 22 minus the thickness of the component limiting plates 23 is greater than the thickness of the female fixture 1.

[0028] The component positioning frame 21, the component limiting frame 22 and the two component limiting plates 23 of the sub-clamp are an integrated plastic structure;

[0029] The shape and size of the outer ring of the component positioning frame 21 is larger than the shape and size of the inner ring of the female fixture 1. When clamping, the component limiting frame 22 passes through the inner ring of the female fixture 1, and the component positioning frame 21 is located behind the female fixture 1;

[0030] The component positioning frame 21 is provided with four through holes 24, which are respectively adjacent to the four corners of the component positioning frame 21. Four locking screws 3 respectively pass through the corresponding through holes 24 of the component positioning frame and are threadedly connected to the threaded holes 11 of the female fixture 1. Three top screws 4 are threadedly passed through the threaded holes 25 of the component positioning frame 21 and abut against the rear surface of the female fixture 1.

[0031] When clamping, the component 6 is placed in the overlapping inner circle of the sub-clamp component positioning frame 21 and the component limiting frame 22, and the front surface of the component 6 is against the rear surfaces of the two component limiting plates 23. The component pressing block 5 is an L-shaped pressing block structure. The horizontal part of each component pressing block 5 extends into the overlapping inner circle of the clamp component positioning frame 21 and the component limiting frame 22 to press the rear surface of the component 6, and the vertical part of each component pressing block 5 is close to the rear surface of the component positioning frame 21.

[0032] The rear surface of the auxiliary positioning plate 7 faces the front surface of the mother fixture 1, and outer convex strips 71 are arranged on the rear surface of the auxiliary positioning plate 7 and adjacent to its two ends, and corresponding inner convex strips 72 are arranged on the rear surface of the auxiliary positioning plate 7 and on the inner side of each outer convex strip 71, that is, the two inner convex strips 72 are located between the two outer convex strips 71, and a groove 73 structure is formed between each outer convex strip 71 and the corresponding inner convex strip 72. The thickness of the outer convex strips 71 and the inner convex strips 72 are equal, that is, the rear surfaces of the outer convex strips 71 and the inner convex strips 72 are located in the same plane. When the components are assembled, the rear surfaces of the two outer convex strips 71 on the auxiliary positioning plate are respectively close to the front surface of the mother fixture 1, that is, the positioning surface of the mother fixture, and the vertical frame portion of the component limit frame 22 extends into the corresponding groove 73 of the auxiliary positioning plate 7, and the rear surfaces of the two inner convex strips 72 are in contact with the front surface of the component 6, that is, the surface to be inspected of the component.

[0033] The steps for clamping components are as follows:

[0034] (1) See Figure 3-Figure 5 , the component 6 is placed in the inner circle where the sub-clamp component positioning frame 21 and the component limiting frame 22 overlap, and the front surface of the component 6 is against the rear surfaces of the two component limiting plates 23, and the rear surface of the component 6 is pressed by four component pressing blocks 5, so that the component is clamped in the sub-clamp 1;

[0035] (2) See Figure 6 , install the auxiliary positioning plate 7 on the female fixture 1, the outer convex strip 71 of the auxiliary positioning plate 7 contacts the front surface of the female fixture 1, and the two outer convex strips 71 of the auxiliary positioning plate 7 are coplanar with the two inner convex strips 72;

[0036] (3) See Figure 7 , the sub-clamp 2 with the component to be tested 6 clamped is installed into the mother clamp 1, so that the front surface of the component 6, i.e., the surface to be tested, contacts the two inner convex strips 72 of the auxiliary positioning plate 7, and the four locking screws 3 are respectively passed through the corresponding through holes 24 of the component positioning frame and then threadedly connected to the threaded holes 11 of the mother clamp 1, that is, the surface to be tested of the component 6 is in stable contact with the auxiliary positioning plate 7; the three top screws 4 are threaded through the threaded holes 25 of the component positioning frame 21 and then abut against the rear surface of the mother clamp 1; under the joint action of the locking screws 3 and the top screws 4, the relative positions of the mother clamp 1 and the sub-clamp 2 are fixed to each other, the surface to be tested of the component to be tested 6 contacts the two inner convex strips 72 of the auxiliary positioning plate 7, i.e., the surface to be tested of the component to be tested is coplanar with the outer convex strips 71, and the outer convex strips 71 are in direct contact with the front surface of the mother clamp 1, i.e., the outer convex strips 71 are coplanar with the front surface of the mother clamp 1, so the surface to be tested of the component 6 is coplanar with the front surface of the mother clamp 1, i.e., the positioning surface of the mother clamp.

[0037] (3) See Figure 1 After completing the clamping, remove the auxiliary positioning plate 7, and the component clamping is completed. The thickness between the front surface of the component 6 and the front surface of the sub-clamp 2 is only the thickness of the component limiting plate 23. The front surface of the component 6 is coplanar with the front surface of the mother clamp 1. The mother-sub clamp is loaded into the device as a whole, and the component loading can be completed only by positioning with the front surface of the mother clamp 1.

[0038] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A positioning fixture for short working distance detection, Features: It includes a mother clamp, a sub-clamp, four locking screws, a plurality of top screws, a plurality of component pressing blocks and an auxiliary positioning plate; The mother fixture is a frame structure, and the sub-fixture is a double-layer frame structure composed of a component positioning frame and a component limiting frame. The inner circles of the component positioning frame and the component limiting frame overlap each other, and the outer circle of the component positioning frame is located at the outer periphery of the outer circle of the component limiting frame. The component limiting frame is fixedly connected to the front surface of the component positioning frame. Two component limiting plates are fixed on the component limiting frame, the two component limiting plates are parallel to the frame of the component limiting frame and are respectively fixed on the top and bottom ends of the inner wall of the component limiting frame, the thickness of each component limiting plate is less than the thickness of the component limiting frame, the front surfaces of the two component limiting plates and the front surface of the component limiting frame are located in the same plane, and the thickness of the component limiting frame minus the thickness of the component limiting plates is greater than the thickness of the mother fixture; The shape and size of the outer ring of the component positioning frame is larger than the shape and size of the inner ring of the female fixture. When clamping, the component limiting frame passes through the inner ring of the female fixture, and the component positioning frame is located behind the female fixture; The component positioning frame is provided with four through holes, which are evenly distributed along the frame of the component positioning frame. Four locking screws are respectively passed through the corresponding through holes of the component positioning frame and then threadedly connected to the threaded holes of the female fixture. Four top screws are threadedly passed through the threaded holes of the component positioning frame and then abut against the rear surface of the female fixture. When clamping, the component is placed in the overlapping inner circle of the sub-clamp component positioning frame and the component limiting frame, and the front surface of the component is against the rear surfaces of the two component limiting plates. The component pressing block is an L-shaped pressing block structure. When clamping, the horizontal part of each component pressing block extends into the overlapping inner circle of the clamp component positioning frame and the component limiting frame to press the rear surface of the component, and the vertical part of each component pressing block is close to the rear surface of the component positioning frame, so as to position the component in the sub-clamp; The rear surface of the auxiliary positioning plate faces the front surface of the mother clamp, and outer convex strips are arranged on the rear surface of the auxiliary positioning plate and adjacent to its two ends, and corresponding inner convex strips are arranged on the rear surface of the auxiliary positioning plate and on the inner side of each outer convex strip, that is, the two inner convex strips are located between the two outer convex strips, and a groove structure is formed between each outer convex strip and the corresponding inner convex strip. The thickness of the outer convex strip and the inner convex strip are equal, that is, the rear surfaces of the outer convex strip and the inner convex strip are located in the same plane. When the components are assembled, the rear surfaces of the two outer convex strips on the auxiliary positioning plate are respectively close to the front surface of the mother clamp, that is, the positioning surface of the mother clamp, and the vertical frame portion of the component limit frame extends into the corresponding groove of the auxiliary positioning plate, and the rear surfaces of the two inner convex strips are in contact with the front surface of the component.

2. A positioning fixture for short working distance detection according to claim 1, Features: The component positioning frame, the component limiting frame and the two component limiting plates of the sub-clamp are an integrated molding structure.

Images