High Pressure/temperature camera

A camera viewing unit for viewing the inside of a reaction vessel or the like is the invention disclosed. This viewing unit has a fixed lens positioned in front of the camera lens. The camera is focused by moving the fixed lens. The camera has a fused lens in front of the fixed lens; this fused lens minimizes corrosion of the unit. There are also easy alignment means to ensure a level picture is transmitted.

This invention relates to a means for viewing the interior of a vessel and, 
more particularly, to a novel system and apparatus for viewing with a 
camera structure. 
BACKGROUND OF THE INVENTION 
There are presently in use containing vessels used in different industries 
such as chemical, food processing, metallurgical and the like. In vessels 
of this nature chemical reactions are conducted, polymerization procedures 
are carried out, beer is brewed, metals or other materials are mixed, and 
other procedures are carried out under controlled temperature and pressure 
conditions. It is necessary in each of these procedures to control and 
determine the progress and alter or adjust the reaction conditions when 
necessary. This control is generally facilitated by a viewing window 
provided in the side of the reaction vessel. By viewing through this 
window, the operator can determine color changes, liquid levels, or other 
visually-determinable factors taking place within the vessel. These 
viewing windows can fail after continued or prolonged usage and could 
cause serious injury to the operator. Window failure can be caused by 
several factors such as corrosion, gasket failure, glass fractures, high 
pressures or uneven glass loading due to attachment stresses and the like. 
There have been some attempts to improve the durability of viewing windows 
and some improvements have been disclosed in U.S. Pat. Nos. 2,744,487; 
3,299,851; 3,837,226 and 4,245,566. Each of these patents disclosed a 
different approach but all lacked the feature of providing a 
corrosion-reducing system or a structure that substantially strengthens 
the window after continued usage. None of these patents provided viewing 
windows sufficient to prevent rupturing of the window when used in high 
pressure vessels that are exposed to corrosive conditions. 
U.S. Pat. No. 4,809,862 (Canty) provided a safety viewing window made up of 
an optically clear window having a transparent disc fused to a metal 
frame. A laminate was then overcoated over the fused disc and frame to 
provide a corrosion-resistant viewing window. The viewing window has means 
for securing it to the vessel in a pressure-tight manner. The unit has 
found wide acceptance but a unit was needed to record activities within 
the vessel or to provide observation means at a remote location. There are 
situations requiring controlling and recording process parameters as they 
occur for viewing immediately or at a later date. There are other 
situations when the operator is absent from the vessel site and process 
progress needs to be viewed or recorded. In other situations, vessel 
reactions could cause explosions or other dangerous reactions. To 
accommodate these situations, the present invention provides a 
camera-viewing structure allowing viewing or recording at a remote 
location where information can be digitized if desired to be analyzed or 
viewed at a later date. Window viewing by an observer can only provide 
instant viewing. If it was desired to play back a chemical reaction to 
determine color changes, liquid levels or other parameters, instant 
viewing through any type window would not provide this opportunity. A 
camera viewing device would afford substantial advantages in addition to 
safety. 
In standard viewing in a high pressure/high temperature system, users have 
been limited to makeshift methods. Generally, to view the interior of a 
vessel at a remote location, the user would have to mount a CCD or CCTv 
Camera onto an existing sightglass window. They would then encounter some 
or all of the following problems that would render the system ineffective: 
(1) The sightglass and CCD lens would become dirty due to dirt external to 
the vessel. 
(2) The process fluid or vapors would leak out or flow out due to a 
sightglass breaking or leaking. This would then destroy the electronics 
making the system worthless. 
(3) Reflection from room lighting would cause the vessel view to disappear. 
The structures of a camera device on a reaction vessel could easily become 
corroded and could fail. Uneven glass loading due to uneven bolt or gasket 
stresses can cause cracking and leakage. Also, corrosive chemicals during 
extended usage could cause failure of these mounting structures or failure 
of the camera being used. The camera systems of the prior art are 
cumbersome, oversized and in many instances tend to reflect light and 
cause image distortion. In addition, focusing and manipulating of the 
camera to provide optimum usage has been difficult when using prior art 
devices. Therefore, while some degree of improvement is provided by camera 
viewing heretofore used, none of these systems provide an adequate system 
for reliable and extended usage. 
SUMMARY OF THE INVENTION 
An object of this invention is to provide a safety camera viewing device 
which is devoid of the above-noted disadvantages. 
It is another object of this invention to provide a lens system which has a 
significant enhancement in view angle over the prior art. In addition, the 
insertion style lenses create an added dimension of bringing the view past 
a nozzle or through a valve. 
Another object of this invention is to provide a viewing system for vessels 
where the operator can monitor at a remote and safe location. 
A further object of this invention is to provide a leak-tight viewing 
system for the interior of low or high pressure vessels where several 
criteria relating to the contents can be determined, controlled and 
monitored. 
A still further object of this invention is to provide a camera viewing 
system that can be easily focused and adjusted after being installed in a 
vessel. 
Another still further object of this invention is to provide a camera 
viewing system where visual observations can be recorded, digitized and 
analyzed during or after viewing. 
A yet still further object of this invention is to provide a camera viewing 
system for viewing the interior of a vessel that will be substantially 
resistant to corrosion, cracking, vapor or liquid leakage and 
deterioration upon extended usage. 
Still yet another object of this invention is to provide a camera viewing 
system with a fused lens that is relatively easy to use, minimizes 
reflections and will allow a precise and non-distorted view of a vessel 
interior and its contents. 
A further object is to provide an easily portable camera viewing system for 
use in vessels such as chemical reactors, fermenting chambers, foaming 
vessels, agitation or mixing vessels and the like. 
Another further object is to provide a camera viewing and monitoring means 
helpful in determining content particle size, fluid density and other 
essential criteria of materials in a pressure vessel. 
The foregoing objects and others are accomplished in accordance with this 
invention by providing a CCD or CCTv Camera viewing means that is fixed in 
place and yet can be adjusted according to the precise object to be 
viewed. The camera viewing means of this invention can be used in high or 
low pressure vessel systems and high and low temperature areas to view the 
interior with a minimum of risk from a safety standpoint. It can also be 
used conveniently in standard viewing of non-pressurized vessel interiors 
such as in baking, mixing vessels and the like. 
The unit of this invention comprises a CCD, CCTV or other suitable camera 
means having a fixed lens. A unit-vessel attachment structure is mounted 
on the front portion of the camera forward of the lens. This attachment 
structure comprises at its front face a fused lens. The lens can be made 
from any suitable material such a inorganic glasses, acrylics, other 
polymeric materials, boron glass and other suitable, optically clear 
materials. It is preferred, however, for the present invention, that a 
substantially strong safety glass be used. The fusing process followed in 
the present invention is similar to that process described in Glass 
Engineering Handbook, Third Edition, Chapter 5, 1984 Library of Congress, 
ISBN 0-07-044823-X by G. W. McLellan and E. B. Shand. If desired, the 
fused lens can be laminated by a process disclosed in this same Glass 
Engineering Handbook, pages 12-15. Both the fusing and lamination process 
disclosed in this Glass Engineering Handbook are hereby incorporated by 
reference in the present disclosure. The laminate can be of any suitable 
material such as pyrex, quartz, mica or other materials to suit the 
desired strength or corrosion-resistance needs. The camera not the lens is 
moved to focus the image in the present invention. The camera is fixed in 
the vessel attachment housing in a manner that permits the camera lens to 
see through an aperture in the vessel attachment housing through the fused 
lens which covers the front most portion of this aperture. Surrounding the 
aperture is a shoulder having an outer threaded periphery. This threaded 
periphery screws into a mating opening in a vessel to be viewed. The 
preferred method of focusing the camera is to turn the camera upon the 
threaded portion of the fixed lens housing which in effect moves the 
camera closer or farther from the front fixed lens. Care must be taken in 
focusing not to unscrew the attachment means too far out so that the 
camera falls out of the vessel connection. Lens extenders are readily 
available to avoid this problem and allow close-up viewing. Leveling or 
orientation of the camera view can be adjusted by loosening the set screw 
on the side of the hex plug. As an alternate, a quick change connection 
can be made by using a plunger spring instead of a set screw. The plunger 
would fit in a recess. The camera is then leveled so that a level picture 
will be transmitted and the camera is kept in place by tightening the set 
screw. The camera fixed lens assembly will turn in relation to the fused 
lens and vessel when the set screw is loosened. Once the camera is 
oriented properly, it is fixed in a level and focused mode by this set 
screw or plunger spring which holds the fixed lens in position.

DETAILED DESCRIPTION OF THE DRAWING AND THE PREFERRED EMBODIMENTS 
In FIG. 1 a camera 2 is attached by a threaded portion 8 to a fixed lens 
housing 6. A CCD Camera is preferred for use in the device of this 
invention. However, any other suitable camera may be used. CCD is an 
acronym for Charged Coupled Device. This CCD Camera is used rather than a 
vidicon tube. A typical CCD Camera useful in this invention is a Sony 
Camera identified as Sony Model No. XC-711. In use, attachment means 3 is 
attached to a vessel 4 (see FIG. 3) by screwing threaded hex plug portion 
5 into a threaded female portion in vessel 4. Other suitable means of 
attachment are flanged, tri-clamps, straight thread O-ring seals, etc. 
Once attachment means 3 is fixed into a threaded aperture in vessel 4, the 
fixed lens housing 6 is screwed into the CCD Camera 2 at its front lens 
section at screw portion 8. The fixed lens housing 6 already is mounted in 
the opening 7 of attachment means or hex plug 5. In the quick change 
design, the plunger spring allows quick change and movement of camera 2 
and fixed lens housing 6. Fixed lens housing 6 has a tubular configuration 
with a back threaded section 8 which conveniently screws into the camera 
lens fitting 9. In focusing the camera, threaded section 8 is loosened or 
tightened until the proper focal length or focus is obtained. The focused 
view is leveled by loosening set screw 10 and rotating camera 2 and fixed 
lens housing 6. When the focusing and orienting is completed, set screw 10 
is tightened to fix the camera 2 and fixed lens housing 6 in position. The 
fixed lens housing 6 has at its rear section closest to the camera a lens 
steel housing 11 which is fixed to housing 6. In the front section of lens 
housing 6 is a glass lens 12 which abuts the inner face of fused lens 13. 
Fused lens 13 is a fused glass to metal (plug 3) plano-plano lens which 
hermetically seals the fixed lens 12 and does not allow any vapors to 
enter the viewing unit. The preferred focusing is accomplished by turning 
the camera 2 upon threaded section 8 of fixed lens housing 6. Camera 2 has 
mounting plates 14 in the event it is desired to connect the camera to 
some other support. In the rear portion of camera 2 are video and power 
connections 15 for connecting the camera viewing unit to the appropriate 
electrical connections. Fused lens 13 is preferably made of soda lime and 
is fused on and flush with the metal surface 16 of attachment means 3 by a 
process as above described in Glass Engineering Handbook. If desired, a 
laminate overcoating may be formed on the outside face of fused lens 13 
for additional protection from the corrosive effects of the vessels 4 
contents. A typical laminating process and laminating materials are 
described in U.S. Pat. No. 4,809,862 . At the rear of camera 2 as noted 
earlier are video and power connections 15 which permit the source of 
electrical energy for transmission of the composite video by coaxel cable 
or fiber optics. These electrical connections 15 also provide for 
electrical connections required for other manipulations of the camera 2. 
FIG. 2 shows an exploded view of the camera viewing unit of this invention 
whereby attachment means 3 is detached from fixed lens housing 6. Housing 
opening 7 permits fixed lens housing 6 to be inserted therein and fixed in 
place by a set screw 10 of FIG. 1 or, alternatively, a plunger spring 
tightening means 17 as shown in FIG. 2. In the embodiment shown in FIG. 2, 
a groove 18 is positioned in the outside wall of fixed lens housing 6. 
Groove 18 receives and locks with ball tightener 19 at the top of plunger 
spring 17 when the housing 6 is fixed in position in aperture or opening 
7. Camera 2 may be focused as described above by turning the camera 2 upon 
threaded fixed housing section 8 or by turning the fixed housing 6 upon 
this same threaded section 8. 
In FIG. 3 a schematic view of a system utilizing the camera unit of this 
invention is illustrated. The unit attachment means 3 is connected to the 
side of vessel 4 in a manner that camera 2 can view the interior of vessel 
4. Threaded section 5 of attachment means 3 is screwed or threaded into 
and through the side of vessel 4 whereby fused lens 13 is in direct visual 
and physical contact with the vessel interior. Fixed lens housing 6 
connects the camera 2 to the interior of attachment means 3 and is fixed 
in place by set screw 10. The unit is electrically connected to a source 
of electrical energy and to a monitor 20 for remote viewing. From the view 
projected in monitor 20, level controllers 21, digitizing means (not 
shown), recording means 22 and data indicator 23 can be manipulated to 
provide the necessary control and information about the contents of vessel 
4. For example, by determining the change in light intensity, particle 
size can be determined or liquid levels controlled, etc. 
The preferred and optimumly preferred embodiments of the present invention 
have been described herein and shown in the accompanying drawing to 
illustrate the underlying principles of the invention but it is to be 
understood that numerous modifications and ramifications may be made 
without departing from the spirit and scope of this invention.