Lens protector device

Abstract: A protection device for a lens used in a scanning apparatus for imaging data on photographic film, comprises a plate (201) and having a finger gripping portion (209,210), a member (202) slidably retained in said plate, a glass piece (206) removably carried by the member, and a biasing member operatively associated with the member for selectively permitting secure holding of the glass piece on the member and easy removal of the glass piece from the member. The plate (201) is provided with a biasing device for securely retaining the member (202) in a desired location such that the glass piece (206) is in a predetermined lens protecting position. A switch is associated with the plate such that the switch is moved to an open position upon movement of the member away from the plate. The biasing member is a pivotally mounted spring (215) configured to hold the glass piece in a desired location on the member and has V-shaped portions to engage portions of the member for positive locking of the spring in the member.

Description: TECHNICAL FIELD The present invention relates to a lens cover or protector, and, more particularly, to a protector for use in a photographic negative film scanning apparatus in which the scanning lens is vertically oriented and prone to having dust and dirt settle thereon. BACKGROUND ART In the past, to the extent that lenses in photographic scanning apparatuses used protective covers at all, the covers were attached directly to the lens casing. This is a particular problem in a scanning apparatus where the various components fit closely together and access thereto is not convenient. Moreover, it is relatively cumbersome process to remove a lens protector or cover in such a system, and this becomes a serious problem when the frequency of cleaning or replacement of the lens cover is fairly frequent. Consequently, the removal of the lens cover can also result in damage to other sensitive components. The patent Abstract of Japan Volume 10 Nr. 19 (P/423) (2076) 20th of January 1986 and JP-A-60172011 (Ricoh K.K.) 5th September 1985 show a dust proof window consisting of a holder, a glas plate and a handle for protecting a lens. The dust proof window being removably attachable along a guide part in which the cylindrical lens is installed. The cylindrical lens remaining installed when the dust proof window is removed from the guide part. Further, attention is drawn to EP-A-0 302 740 which shows a lens cap which removably covers a photographic lens of a video camera which is capable of photographing an object at very short distance. To enable title photography to be carried out the lens cap is capable of removably receiving a title element such as a title recording paper. Therefore, title photography can be achieved in the macro mode with the lens cap attached to an exposed end portion of the photographic lens. DISCLOSURE OF INVENTION It is an object of the present invention to provide a lens protector which can be changed easily fairly frequently without concern about damage to other system components. It is another object of the present invention to provide a lens protector which makes it extremely easy for the scanning apparatus operator to utilize by providing a lens protector case attached permanently to the chassis or frame and spaced closely to the lens of an imager unit, and a slide member which can be pulled from the casing to remove the cover for cleaning or replacement. The optical lens cover itself is maintained securely in the slide member by a spring biased clamping arrangement which facilitates easy removability of the lens cover but securely and accurately holds the lens cover in the appropriate position when the scanning apparatus is in operation. The above objects are achieved by the protection device as set forth in claim 1. Preferred embodiments of the invention are shown in the dependent claims. BRIEF DESCRIPTION OF DRAWINGS These and other features, objects and advantages of the present invention will become more apparent from the following detailed description of currently contemplated modes of a lens protector device when taken in conjunction with the accompanying drawings wherein: Figure 1 is a perspective view of the front of a scanning apparatus for use with photographic film in which the lens protector is shown between an imaging unit and a pendulum-like gate; Figure 2 is a front elevational view of the scanning apparatus shown in Fig. 1; Figure 3 is aperspective exploded view of the lens protector shown generally in Figs. 1 and 2; Figure 4 is a top plane view of the slide used in the lens protector; Figure 5 is a side elevational view of the slide shown in Fig. 4; Figure 6 is a perspective view of the slide shown in Figs. 4 and 5 with the lens retainer in the released position so that the optical glass lens cover can be removed; and Figure 7 is a bottom plan view of the lens protector device showing the arrangement of the switch relative to a slide member which shuts off the scanning apparatus when the slide is removed for cleaning or replacement of the optical glass. MODES FOR CARRYING OUT THE INVENTION Referring now to the drawings and, in particular, to Figs. 1 and 2, a photographic negative film scanning apparatus for scanning and digitizing images on frames of the film is designated generally by the numeral 10. The apparatus 10 includes a board 11 on which are mounted conventional film transport reels 12, 13, a capstan drive 14, an integrating cavity 15, a conventional imager with imaging board designated generally by the numeral 16, a DX bar code reader 17 for determining the type of film being scanned, a film cleaning apparatus 18, a bar code reader 24 for reading order processing data, and spring-biased tension rollers 19, 20 to maintain the film at a substantially constant tension during the high resolution scanning pass. In addition, other idler rollers 21, 22, 23 and 25 are mounted on the board 11 to maintain a smooth but tight path for the film F shown in long and short dash lines. A gate 100 mounted on an optical chassis 400, is rotated, during the high resolution scanning pass in an arc of about 6½° on both sides of a vertical axis constituting an initializing position in which the gate assumes during the low resolution operation. The optical chassis 400 is described in co-pending application Serial No. 071 943, 426 , entitled OPTICAL CHASSIS, filed in the names of Eric P. Hochreiter, et al. on September 14, 1992, corresponding to EP-A-0 588 295 (prio. date 14/09/92, publ. date 23/03/94). The film F which is supplied from reel 12 shown in Figs. 1 and 2 is advanced by the capstan mechanism 14 by pulling the film F from the supply reel 12 over the gate 100 and onto the take-up reel 13. It will be understood, of course, that the capstan mechanism 14 can be disposed on the right-hand side of the scanning apparatus to push the film F over the gate 100 without departing from the scope of the present invention. Inasmuch as the details of the optical chassis 400 are not necessary for an understanding of the present invention, further details with respect thereto are dispensed with and the contents of said application are incorporated by reference herein for background as to the overall construction of the scanning apparatus. Referring now to Fig. 3, the lens protector device is designated generally by the numeral 200 and comprises a slide mount plate 201 in which an imager cover slide member 202 is slidably arranged in channels 203 provided in the plate 201 to permit the slide member 202 to be selectively inserted into and removed from the plate 201. A switch is provided on the bottom of the plate. The switch has a spring arm 205 which is closed when the slide member 202 is inserted all the way into the plate so as to place an optical glass lens cover 206 over and in close proximity to the lens of the imaging unit 16 as seen in Fig. 1. As can be seen more clearly in Fig. 7, the arm 205 is flush with the wall of the plate 201, as shown in solid line, when the slide has been fully inserted into the plate so that the switch connects the scanning apparatus 10 to the power supply to render the apparatus operational. When the slide has been pulled away from the plate sufficiently (just a short distance as shown by the long and short dashed line in Fig. 7), the power supply is interrupted so that the scanning apparatus 10 is shut off as a safety feature for the lab operator. To retain the glass cover 206 in a precise position over the lens of the imaging unit 16, a slide retainer spring 207 is provided in the plate 201 to engage in a notch 208 (Fig. 4) arranged at an edge of the slide member 202 near its forward free end. The slide member can be provided with an enlarged end having recessed portions 209, 210 on the respective upper and lower surfaces to allow the fingers of the scanning apparatus operator to more easily grasp the slide member 202 for pulling it out from the plate 201. A glass cover retainer spring 211 having a bight portion 212 held in a pivoting manner on the slide member 202 is provided with a V-shaped portions 213 on each side of the spring 211 to engage under channels 214 provided in the slide 202 as shown most clearly in Fig. 3. A portion of the spring 211 extends beyond the free end of the side of the slide 202 so that, after removal of the slide 202 from the plate 201 and shutting down of the scanning apparatus 10, the operator can grasp both end portions 215 and squeeze them toward one another to extract the spring 211 from the channels 214. The operator pinches the two end portions 215 together against the bias of the spring 211 and moves the spring 211 to the position shown in Fig. 6. This allows the glass cover 206 which is shown to be of roughly square shape sitting in a recessed area of the slide member 202 for precise and quick location of the lens cover to be replaced or removed for cleaning. The arrangement of the lens protector device 200 is particularly attractive in the scanning apparatus in which the imaging unit 16 presents a vertically oriented lens where dust and dirt more easily settle on the lens. The plate 201 can be mounted to the optical chassis 400 so as to be 0,038 to 0,051 cm (.015 to .020 inch) from the lens. A shield plate 216 can be used with the lens protector device 200. The shield plate 216 has an aperture 219 sized to serve as a light baffle that eliminates stray light from entering the imaging lens in the imaging unit 16. With the use of such a plate, the configuration of the slide mount plate 201 can be simplified by eliminating the channels 203 and by avoiding the need for a notch 217 to hold the slide retainer spring 207 in the plate 201. In other words, the construction of the slide mount plate can be greatly simplified with the use of a top plate 216. The slide member 202 can also be provided with a region 218 on its top bottom surface to assure that the slide member will be installed in the plate 201 in the correct orientation. Although the invention has been described and illustrated in detail, it is to be clearly understood that the same is by way of illustration and example, and is not to be taken by way of limitation.

Claims: A protection device (200) for a lens, comprising a plate (201), a member (202) slidably retained in said plate with a glass piece (206) characterised in that the glass piece (206) is removably carried by the member, a biasing device (211) is operatively associated with the member for selectively permitting secure holding of the glass piece on the member and easy removal of the glass piece from the member, and a switch (205) is associated with the plate such that the switch is moved to an open position upon movement of the member away from the plate, so that the power supply of a scanning apparatus can be interrupted. The device according to Claim 1, wherein the plate (201) is provided with a first biasing device (207) for securely retaining the member in a desired location such that the glass piece is in a predetermined lens protecting position. The device according to Claim 1 or 2, wherein the member (202) is provided with at least one gripping portion (209, 210). The device according to Claim 1 or 2, wherein a second biasing device (211) is provided comprising a pivotally mounted spring configured to hold a the glass piece (206) in a desired location on the member and having V-shaped portions to engage portions of the member for positive locking of the spring in the member. The protected device according to any of the preceding Claims, wherein the glass piece (206) is optical glass. The device according to Claim 1, wherein means (216, 219) for providing a light baffle is associated with the plate (201). A scanning apparatus (10) having a lens for receiving image data on a photographic film, characterized by comprising a device (200) for protecting the lens according to claim 1. The scanning apparatus according to Claim 7, wherein the plate (201) is provided with a first biasing device (207) for securely retaining the member in a desired location such that the glass piece is in a predetermined lens protecting position a short distance from the lens. The scanning apparatus according to Claim 7 or 8, wherein the member (202) is provided with at least one gripping portion (209, 210). The scanning apparatus according to Claim 7 or 8, wherein a second biasing device (211) is provided comprising a pivotally mounted spring configured to hold the glass piece (206) in a desired location on the member and having V-shaped portions to engage portions of the member for positive locking of the spring in the member. The scanning apparatus according to any of the preceding Claims 7-10 wherein the glass piece (206) is optical glass. The scanning apparatus according to anyone of Claims 7-11, wherein means (216, 219) for providing a light baffle is associated with the plate (201).

Inventors: LAHCANSKI TOMI, PFAFF DOUGLAS J, SCHWAB FREDERICK J, LAHCANSKI, TOMI, PFAFF, DOUGLAS J., SCHWAB, FREDERICK J., Lahcanski, Tomi, c/o Eastman Kodak Company, Pfaff, Douglas J., c/o EASTMAN KODAK COMPANY, Schwab, Frederick J., c/o EASTMAN KODAK COMPANY
Applicants: EASTMAN KODAK CO, EASTMAN KODAK COMPANY
Application year: 1993
Main classification: G03B17
IPC codes: G03B17, G02B7