Patent Publication Number: US-2021195067-A1

Title: Imaging device enclosure

Description:
BACKGROUND 
     Cameras or other types of imaging devices are commonplace in various manufacturing environments. For example, functionality of robots in manufacturing may rely on vision systems to detect and identify various components. Such vision systems may include various types of imaging devices, such as optical cameras or thermal imaging devices, for example. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a more complete understanding of various examples, reference is now made to the following description taken in connection with the accompanying drawings in which: 
         FIG. 1  illustrates an example system with an imaging device; 
         FIG. 2  illustrates another example system; 
         FIG. 3  illustrates another example system; 
         FIG. 4  illustrates an example system for three-dimensional printing; and 
         FIG. 5  is a flow chart illustrating an example method. 
     
    
    
     DETAILED DESCRIPTION 
     Various examples described herein relate to an enclosure for a camera or other imaging device. In various examples, accumulation of contaminants, such as powders or aerosols in a three-dimensional printing environment, on the camera (e.g., on the lens of the camera) is prevented by providing the camera in the enclosure. The enclosure includes an aperture through which the field of view of the camera passes. Thus, the enclosure does not block the view of the camera. An air pressure in the enclosure is maintained at a higher level than the air pressure outside the enclosure, thus preventing contaminants from entering the enclosure. The higher air pressure is maintained by forcing air into the enclosure through an air intake (e.g., a fan). The air is directed out of the aperture while maintaining the higher pressure within the enclosure. 
     As noted above, vision systems with various types of imaging devices, such as optical cameras or thermal imaging devices, may be used in any of a variety of environments. For example, various manufacturing environments may employ imaging devices to facilitate operation of robots. One example of such a manufacturing environment has developed recently with the rise of three-dimensional (3D) printing technology. In various examples, cameras may be used to identify proper fusion or solidification of a material used in manufacturing of 3D-printed objects. In one example, a thermal camera may be used to detect that the material is reaching a proper or desired temperature for proper fusion. 
     In such environments, a 3D printer may cause particulates (e.g., powder) or other contaminants that may adhere to a lens or other component of the imaging device to become airborne and accumulate on the imaging device, resulting in interference in the capturing of the image. For example, in the case of a thermal camera, with sufficient accumulation of contaminants, the thermal camera may detect the temperature of the accumulated contaminants rather than the targeted material being fused. Various examples described herein may prevent such accumulation on the imaging device. 
     Referring now to  FIG. 1 , an example system with an imaging device is illustrated. The example system  100  of  FIG. 1  includes an enclosure  110  with an imaging device  120  positioned therein. In various examples, the enclosure  110  may be formed of a variety of materials, including metals, plastics or glass, for example. In one example, the enclosure  110  is formed of a transparent or semi-transparent material. Further, the enclosure  110  may be formed in any of a variety of shapes. In one example, as illustrated in the example of  FIG. 1 , the enclosure  110  is formed in the shape of a rectangular box. 
     In the example of  FIG. 1 , the imaging device  120  may be any of a variety of imaging devices, such as cameras. In one example, the imaging device  120  is an optical camera. In another example, the imaging device  120  is a thermal camera for capturing thermal data such as temperature. In various examples, the imaging device  120  may be a light-producing device, such as a laser, for example. 
     The enclosure  110  substantially separates the imaging device  120  from the environment outside the enclosure  110 . In this regard, various examples of the enclosure  110  may isolate and protect the imaging device  120  from contaminants that may be present in the environment outside the enclosure  110 . Such contaminants may include dust particles commonly present in the atmosphere or specific contaminants that may be present in the particular environment of the enclosure  110  and the example system  100  of  FIG. 1 . 
     In the example system  100  of  FIG. 1 , the enclosure  110  is provided with an air intake  130  to direct or force air into the enclosure  110 . In this regard, the air intake  130  may be a channel and may include a pump, a fan or other device to facilitate flow of air into the enclosure, as illustrated by the large arrow entering the enclosure  110 . In various examples, the air forced into the enclosure  110  through the air intake  130  may be clean or purified air that is substantially free of contaminants. 
     The enclosure  110  of the example system  100  further includes an aperture  140 . In this regard, the enclosure  110  may have a body in which the aperture  140  may be formed. Thus, the enclosure  110  substantially surrounds the imaging device  120 . The aperture  140  may allow air to escape the enclosure  110 . In one example, the air intake  130  and the aperture  140  are sized to maintain an air pressure level in the enclosure  110  (P E ) that is greater than the air pressure of the environment outside the enclosure  110  (P A ). In this manner, any contaminants that may be present in the environment outside the enclosure  110  are prevented from entering the enclosure  110 , thereby protecting the imaging device  120 . 
     In various examples, the aperture  140  may be positioned anywhere on the body of the enclosure  110 . In one example, as described in greater detail below, the aperture  140  may be positioned such that the field of view of the imaging device  120  passes, either partly or entirely, through the aperture  140 . In various examples, the aperture  140  may be formed with a circular, rectangular or square shape. The shape of the aperture  140  may be selected to correspond to the shape of the field of view of the imaging device  120 . In such cases, the aperture  140  may be positioned such that the aperture  140  is concentric with the field of view of the imaging device  120 . 
     Referring now to  FIG. 2 , another example system  200  is illustrated. The example system  200  of  FIG. 2  may be similar to the system  100  of  FIG. 1  and includes an imaging device, such as a camera  220 , within an enclosure  210 . In the example system  200  of  FIG. 2 , the enclosure  210  is formed in the shape of a rectangular box. As noted above, in other examples, the enclosure  210  may have any of a variety of shapes. 
     The example system  200  of  FIG. 2  includes a fan  230  which functions as an air intake for the enclosure  210 . In this regard, the fan  230  may be provided to force air into the enclosure  210 . The fan  230  may draw air from outside the enclosure  210  into the enclosure  210 . For example, the fan  230  may draw air from the atmosphere outside the enclosure  210 . In other examples, the fan  230  may draw air from an air reservoir (not shown) which includes air that is substantially free from contaminants. For example, the air reservoir may include filtered or purified air. 
     In the example system  200  of  FIG. 2 , the camera  220  is positioned proximate to one wall of the enclosure  210 . An aperture  240  is formed on a wall of the enclosure that is opposite from the camera  220 . Positioning the aperture  240  on the opposite wall avoids interference of the body of the enclosure  210  with the field of view of the camera  220 . Thus, the camera  220  may have a clear view of the desired subject (not shown) without the view being blocked by the body of the enclosure  210 . Further, as noted above, the fan  230  and the aperture  240  are sized to maintain a greater air pressure inside the enclosure  210  than outside the enclosure  210 , thus preventing contaminants from outside the enclosure  210  from entering the enclosure  210  through the aperture  240 . 
     The example system  200  of  FIG. 2  further includes a cap  242  to allow selectively opening or closing of the aperture  240 . In various examples, the cap  242  may be used to close the aperture  240  when the system  200  (e.g., the camera  220 ) is not in use. In this regard, the cap  242  may protect various components of the camera  220  (e.g., lens) from contaminants. The cap  242  provides an alternative to a lens cap, which may be difficult to install on and remove from the camera  220  within the enclosure. The cap  242  may be removed from the aperture  240  to allow air to flow out of the aperture  240  when the system  200  is in use. 
     Referring now to  FIG. 3 , another example system  300  is illustrated. The example system  300  of  FIG. 3  includes an enclosure  310  with a camera  320  positioned therein. As noted above, the enclosure  310  substantially isolates the camera  320  from the outside environment. The example system  300  of  FIG. 3  includes an air intake  330  through which air is forced into the enclosure  310  and an aperture  340  to allow air to escape from the enclosure  310 . 
     In the example system  300  of  FIG. 3 , the air intake  330  is coupled to air reservoir  350 . As noted above, the air reservoir  350  may include air that is substantially free of contaminants. Air from the air reservoir  350  is delivered to the air intake  330  by a pump  360 . The pump  360  may be activated when the system  300  is in use and may be de-activated when the system  300  is not in use. In other examples, the pump  360  may be replaced with a valve coupled to a pressurized air reservoir  350 . The valve may be opened during operation and closed during non-use of the system  300 . 
     In the example system  300  of  FIG. 3 , the pump  360  may be operated to force air into the enclosure  310  in a diffused manner, as indicated by the short arrows  332  in  FIG. 3 . In another mode, the pump  360  may be operate to cause a strong stream of air to be pulsed, or puffed, onto the camera  320 , as indicated by the long arrow  334  in  FIG. 3 . 
     The aperture  340  in the enclosure  310  of the example system  300  of  FIG. 3  is sized and positioned to allow the field of view  322  of the camera  320  to pass therethrough. In other examples, the aperture  340  may allow at least part of the field of view to pass through the aperture  340 . For example, in some cases, the camera  320  may capture the desired subject without use of the entire field of view of the camera  320 . Accordingly, the aperture  340  may be sized and positioned to allow sufficient field of view to pass therethrough to capture the desired subject. 
     Referring now to  FIG. 4 , an example system for three-dimensional (3D) printing is illustrated. In various 3D printing systems, a material such as a powder is deposited in layers, and each layer may be fused in selected areas to form a solid object. In the example system  400  of  FIG. 4 , a chamber  402  is provided with a 3D print build portion  404 . Various carriages (not shown) may deposit the material (e.g., powder) in layers in the 3D print build portion  404 , and the layer may be fused by, for example, application of a laser (not shown). In other examples, the fusing may be achieved by application of energy or heat from other sources, such as a quartz infrared halogen lamp.  FIG. 4  illustrates an example object  406  formed of fused material surrounded by unfused material  408  remaining at each layer. 
     The example system  400  of  FIG. 4  is provided with an enclosure  410  within the chamber  402 . The enclosure  410  is similar to the enclosures  110 ,  210 ,  310  described above with reference to  FIGS. 1-3 . As noted above, the enclosure  410  may be formed in any of a variety of shapes such as, for example, a rectangular box. A camera  420  is housed within the enclosure  410 . The camera  420  may be provided to, for example, capture images of the 3D print build portion  404  to monitor the 3D printing operation. For example, the camera  420  may be a thermal camera to monitor the temperature of the layers of material to ensure proper fusing. 
     During operation of the 3D printing system, the powder or other contaminants may travel into various portions of the chamber  402 . In this regard, the enclosure  410  substantially isolates the camera  420  from the remainder of the chamber  402  to protect the camera  420  from the contaminants. In order to further protect the camera  420  from the contaminants in the chamber  402 , the enclosure  410  is provided with an air intake  430  and an aperture  440  to maintain a higher air pressure within the enclosure (P E ) than the air pressure in the chamber (P C ). As noted above, air may be forced through the air intake  430  and allowed to escape from the aperture  440 . The air intake  430  and the aperture  440  are sized to maintain a desired differential (P E -P C ) in the air pressures. 
     As illustrated in  FIG. 4 , the example camera  420  has a field of view  422  which at least encompasses a desired portion of the 3D print build portion  404 . The aperture  440  in the enclosure  410  is sized and positioned to allow the field of view  422  of the camera  420  to pass through the aperture  440 . 
     Referring now to  FIG. 5 , a flow chart illustrates an example method. The example method  500  of  FIG. 5  includes forcing air into an enclosure (block  510 ). As noted above, air may be forced into an enclosure (e.g., the enclosure  110  of  FIG. 1 ) through an air intake (e.g., the air intake  130  of  FIG. 1 ). Further, as described above with reference to  FIGS. 1-4 , the enclosure includes an imaging device, such as the imaging device  120  of  FIG. 1 . 
     The example method  500  further includes directing air out of the enclosure through an aperture (block  520 ). Forcing air into the enclosure includes forcing sufficient air into the enclosure to maintain an air pressure level in the enclosure greater than an air pressure outside the enclosure. As described above with reference to  FIG. 1 , the air intake  130  and the aperture  140  are sized to maintain an air pressure level in the enclosure  110  (P E ) that is greater than the air pressure of the environment outside the enclosure  110  (P A ). 
     Thus, in accordance with various examples described herein, accumulation of contaminants, such as powders or aerosols in a three-dimensional printing environment, on an imaging device is prevented by providing the imaging device in an enclosure. An aperture allows the field of view of the imaging device to pass therethrough. An air pressure difference prevents contaminants from entering the enclosure, thereby protecting the imaging device. 
     The foregoing description of various examples has been presented for purposes of illustration and description. The foregoing description is not intended to be exhaustive or limiting to the examples disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from practice of various examples. The examples discussed herein were chosen and described in order to explain the principles and the nature of various examples of the present disclosure and its practical application to enable one skilled in the art to utilize the present disclosure in various examples and with various modifications as are suited to the particular use contemplated. The features of the examples described herein may be combined in all possible combinations of methods, apparatus, modules, systems, and computer program products. 
     It is also noted herein that while the above describes examples, these descriptions should not be viewed in a limiting sense. Rather, there are several variations and modifications which may be made without departing from the scope as defined in the appended claims.