This application claims the benefit of German Patent Application No. 10 2017 120 138.6, filed Sep. 1, 2017, the contents of which is incorporated herein by reference as if fully rewritten herein.
The invention relates to a clear view screen, in particular for machine enclosures and also for other applications.
Rotating viewing windows are frequently used to ensure being able to see through vision panels that are subjected to soiling and, in particular, splashing or gushing fluids, such as water, oil or the like.
Such a rotating viewing window is known from U.S. Pat. No. 3,188,700, for example, and is also known from DE 10 2008 045 793 A1.
The known viewing window comprises a round frame to be placed onto a viewing panel or to be inserted into an appropriate opening of the viewing panel. A fixedly arranged first disk, which centrally carries a bearing for a second, rotating disk, is provided in the frame. The rotating disk is arranged on the side of the round disk that is subjected to dirt or fluid. A drive for the rotating disk is accommodated in the annular frame of the arrangement. The drive is supplied with operating current via a cable.
It is also known from U.S. Pat. No. 3,188,700 to accommodate the drive of the rotating disk on the central bearing unit.
Fluid and dirt are thrown away from the rotating disk by way of a spinning action, so that a clear view is maintained as soon as the disk rotates sufficiently quickly.
Such clear view screens can be used, in particular, on machine tools where the cooling lubricant that is used in the working chamber and washes constantly or in a gushing manner against the viewing panels impairs the view through the viewing panel. The clear view screen allows the processing operations taking place in the working chamber to be observed.
In addition, a camera housing serving as protection against rain is known from DE 197 46 740 A1, which on the light entry side is closed by a rotatably mounted, driven clear view screen. The lens of the camera is arranged in the direct vicinity of the rotating disk. The optical axis of the camera runs through the rotating disk, so that the camera is able to record a clear picture even when impinging liquids act on the housing. Moreover, a battery for operating the motor of the rotating disk is accommodated in the rain protection housing of the camera.
It is the object of the invention to create a clear view screen that not only grants persons a view of an area to be observed, but also allows mechanical monitoring of the area to be viewed. In particular, the clear view screen is to be low-maintenance and suitable for continuous use.
This object is achieved by the clear view screen according to claim 1, which is suitable, in particular, for machine enclosures, but also for other applications.
The clear view screen according to the invention comprises a first transparent disk, which can be attached to a machine enclosure or another wall, in particular a transparent pane or the like. The first transparent disk is preferably designed and arranged so as to seal a potential opening provided in the separating wall in a fluid-tight manner, or at least in a manner that offers protection against splashing water. If the separating wall is transparent, the first transparent disk can also be placed onto the separating wall or be formed thereby.
The first disk carries a bearing device for a second disk, which is rotatably mounted and driven. A driving device is used for driving purposes, which preferably, but not necessarily, is designed as an electric drive. The driving device can be accommodated in a, preferably annular, housing that is arranged on the outer edge of the first disk. In this way, the centrally arranged bearing device can have a slim design, which is to say have an outer radius that is small compared to the radius of the rotatably mounted disk, thereby exposing a large field of vision.
A camera is arranged on one side of the first disk, the lens thereof having a viewing direction that runs through the second disk. The camera preferably has outside dimensions that are smaller than the outside dimensions of the bearing device. The unobstructed view through the clear view screen is thus not impaired. It is not only possible for persons to view the region to be observed, but also to carry out camera recordings or camera monitoring.
For energy supply purposes, the camera is connected to the driving device. In this way, it is possible to continuously operate the camera without replacing a battery. Furthermore, sufficient operating power is provided so as to enable radio-based data transmission from the camera to an outside receiver without difficulty, even over extended ranges and in an environment subject to electromagnetic interference.
If the driving device is an electric driving device, the camera can be connected to the driving device in that the camera is connected to the energy supply system, for example a supply cable, which supplies operating power to the driving device, and thus also the camera. However, it is also possible to connect the camera to the rotating disk, and thus ultimately to the driving device, by way of an alternating magnetic field. If one or more permanent magnets are arranged on the disk, which revolve together with the disk, and if induction coils are arranged on the image recording device, the operating voltage necessary for supplying the camera with power can be regeneratively generated from such coils. The permanent magnets may form part of the electric drive connected to the disk.
The camera is preferably held on a carrier, which extends from the annular housing inwardly in a radial direction. The carrier can form a cantilevered tongue or can be arranged to as to rest against the second disk. It is possible to arrange the camera on the side of the first disk facing the second disk and on the side of the first disk facing away from the second disk. The camera is preferably permanently installed and no access thereto is provided for an operator. However, it is protected to a high degree both mechanically and against fluids. This applies in particular when it is arranged in a space through which sealing air flows. A separate camera protective housing, which would enclose the carrier and the camera itself, which is to say the entire image recording system for operating the camera, is not present.
The camera can be rigidly attached to the carrier. As an alternative, it can be connected to the carrier via a spring and/or damper device. Such a flexible and damping device can be a spring-loaded universal joint, for example, which together with the camera establishes a mechanical resonant frequency that is preferably outside, and in particular below, a frequency spectrum of excitation frequencies that are transmitted as oscillations to the clear view screen.
The connection of the camera to the electric driving device preferably takes place only by way of two connecting lines of the camera, which are connected to connecting terminals of the driving device. This supplies the driving devices and the camera with operating power via the same supply line. The driving device and the camera can include electronic circuits for this purpose, which, from the electrical power supplied via the cable, conduct the respective voltages and currents suitable for operating the camera and the driving device, and decouple these from one another.
As an alternative, the camera can be supplied with energy by the electric or magnetic stray field of the electric driving device, and can thus be connected via the stray field to the driving device. For example, as described above, permanent magnets connected to the circumference of the rotating disk can generate alternating magnetic fields, which are collected and utilized by induction coils, on the camera arranged in the vicinity of the outer circumference of the rotating disk, or the operating circuit thereof. This solution is also practicable with clear view screens driven by compressed air, in which the rotatably mounted disk carries at least one permanent magnet for supplying the camera with power.
Refinements and modifications of the clear view screen according to the invention are the subject matter of the drawings, the description or claims. In the drawings:
The composition of the clear view screen 10 can essentially be derived from
The first disk 15 carries a bearing device 17 for a second disk 18 so as to hold the same at a distance from the first disk 15 and mount it rotatably about a center line 19. The center line 19 is preferably also the center line of the first disk 15, so that the two disks 15, 18 are arranged concentrically with respect to one another, and preferably parallel to one another. The bearing device 17 preferably comprises one or more rolling bearings 17a, 17b, so that the second disk 18 can be easily rotated about the axis of rotation 19.
As is furthermore apparent from
The portion of the housing 16 receiving the socket 32 can, for example, be made of an electrically insulating material, such as plastic material, or can comprise plastic inserts that receive the contact sockets 32. The cable 14 is connected to the housing 16 by way of a screw joint 43, a terminal box or the like. At the same time, the at least two cores of the cable 14 are connected to the control circuit 26 of the driving device 20 so as to supply both the camera 28 and the driving device 20 with electric energy. As an alternative, the cable can also comprise more than two cores to supply both the camera and the driving device 20 with energy. As another alternative, two or more jointly routed cables may be provided, instead of one cable. The cable can be a bus cable, via which energy is supplied to both the driving device and the image recording device 33. The bus cable can, alternatively or additionally, also be configured to transmit control pulses, for example activation and deactivation pulses for the camera 28 or the driving device, actuating pulses for an actuator of the camera 28 and/or image or video data.
The camera 28 can be supplied with power via flexible lines or via conductor tracks 44, 45, which extend across the flexible webs 36 to 38 and the intermediate ring 35 and lead to attachment openings 39, 40 for receiving the screws 30, 31. The conductor tracks 44, 45 can also connect the camera 28 to further circuit components.
For power conditioning, the carrier 27 can be provided with an operating circuit 41, which filters, smooths, decreases or increases the voltage supplied via the screws 30, 31 and conductor tracks 44, 45.
The camera 28 can include means suitable for wirelessly transmitting recorded images. As an alternative, such wireless transmission means may be part of the operating circuit 41. In the latter case, one or more lines 42 lead from the camera 28 to the operating circuit 41. The lines 42, in turn, can be conducted across the intermediate ring 35 and the flexible webs 36, 37, 38. This is only schematically indicated in
The described clear view screen 10 operates as follows:
During operation, the clear view screen 10 receives electrical power, in the form of DC or AC current, with a substantially defined voltage via the cable 14. The particular voltage is applied to the control circuit 26 on the one hand and, via the screws 30, to the operating circuit 41 on the other hand. The control circuit 26 brings about an activation of the coils 24, whereby the second disk 18 is caused to rotate quickly. At the same time, the camera 28 is activated via the operating circuit 41, which records images, videos or video sequences and makes these available via the wireless interface, for example a WLAN interface. The rotatable disk 18 keeps the viewing region free, both for persons present in the observer space and for the camera 28. Due to the small dimensions of the camera 28, the camera does not impair the view. This holds true, in particular, when the dimensions of the image recording device 33 are smaller than the dimensions of the bearing device 17.
Where necessary, the spring and damping device 34 can also be designed as an angle setting device. Accordingly, the flexible webs 36, 37, 38 can be provided with actuators, for example piezo actuators, or be designed as actuators themselves. These actuators can be activated by the operating circuit 41, for example automatically or in accordance with received wireless commands, so as to align the camera 28 with regions of interest in the space 12 to be observed.
Another modified embodiment of the clear view screen 10 is apparent from
It is pointed out that the invention is not limited to clear view screens 10 comprising a driving device that is accommodated on the housing side. Rather, the rotary drive of the disk 18 may also be arranged in or on the bearing device 18, wherein the cable used to supply power then extends across the first disk 15, from the outside, to the center with the bearing device 17 and the driving device. In this case, the cable can be present on or in a carrier, which also carries the image recording device 33.
The clear view screen according to the invention comprises two transparent disks, of which one is fixed and the other rotates. A camera 28, which in any case looks through the rotating disk 18, is arranged between the two disks 15, 18, or on the side of the fixed disk 15 facing away from the space 12 to be observed. The camera 28 is supplied with power via the power supply unit of the driving device 20, so that continuous operation is also possible when the camera 28 is arranged in a space not accessible for maintenance, for example between the first and second disks or between the first disk and an uninterrupted separating wall.
Number | Date | Country | Kind |
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102017120138.6 | Sep 2017 | DE | national |