Systems for blade sharpening and contactless blade sharpness detection
11772223 ยท 2023-10-03
Inventors
- Vitaly Tsukanov (Lviv, UA)
- Yura Bashtyk (Lviv, UA)
- Ivan Romanyshyn (Lviv, UA)
- John R. Ellis (Arlington, MA, US)
Cpc classification
B24B51/00
PERFORMING OPERATIONS; TRANSPORTING
International classification
Abstract
A blade sharpness detection system for determining a sharpness of a blade without mechanical contact with the cutting edge of the blade. An optical inspection unit is operative to inspect blade sharpness optically, and a blade positioning and guidance mechanism is disposed to position and guide the blade in relation to the optical inspection unit. An output display is operative to provide a visual output of the sharpness of the blade. The optical inspection unit, which can be a reflective optical sensor, and the blade positioning and guidance mechanism are retained by a pivotable support structure. The positioning and guidance mechanism can be formed by first and second pairs of rotatable spheres, each pair of rotatable spheres disposed in immediate juxtaposition to act as rolling supports for the blade.
Claims
1. A blade sharpening and blade sharpness detection system for permitting sharpening of a blade and a determination of a sharpness of a blade in a single system, the system comprising: a housing; a blade sharpening mechanism retained by the housing; an optical inspection unit retained by the housing wherein the optical inspection unit is operative to inspect blade sharpness optically and wherein the optical inspection unit comprises a light source and an optical sharpness sensor operative to acquire light reflected from the blade whereby reflected light intensity can be converted to a measurement of blade sharpness; and a blade positioning and guidance mechanism retained by the housing wherein the blade positioning and guidance mechanism is disposed to position and guide the blade in relation to the optical inspection unit; wherein the optical inspection unit and the blade positioning and guidance mechanism are retained by a pivotable support structure within the housing; wherein the positioning and guidance mechanism comprises first and second rotatable spheres disposed in a pair with the first rotatable sphere disposed in immediate juxtaposition to the second rotatable sphere and with the first and second rotatable spheres spaced from the optical inspection unit.
2. The blade sharpening and blade sharpness detection system of claim 1 further comprising an output display operative to provide a visual output of the sharpness of the blade in a localized position.
3. The blade sharpening and blade sharpness detection system of claim 1 wherein the pivotable support structure is pivotable about a pivot axis in relation to a pivot support cradle.
4. The blade sharpening and blade sharpness detection system of claim 1 wherein the support structure has first and second opposed walls separated by a guidance and sensing channel, wherein the optical inspection unit is in optical communication with the guidance and sensing channel, and wherein the blade positioning and guidance mechanism is disposed within the guidance and sensing channel spaced from the optical inspection unit.
5. The blade sharpening and blade sharpness detection system of claim 1 wherein the optical inspection unit comprises a reflective optical sensor.
6. The blade sharpness detections system of claim 5 wherein the reflective optical sensor has an optical pair comprising an emitter and a photodetector.
7. The blade sharpening and blade sharpness detection system of claim 1 wherein the blade positioning and guidance mechanism further comprises first and second pairs of rotatable spheres, wherein the spheres of each pair of rotatable spheres are in immediate juxtaposition, and wherein the pairs of rotatable spheres are retained in spaced relation to one another and in relation to the optical inspection unit.
8. The blade sharpening and blade sharpness detection system of claim 7 wherein the pairs of spheres are disposed in corresponding positions distally and laterally spaced from the optical inspection unit whereby the optical inspection unit is centered between and proximal to the pairs of spheres.
9. The blade sharpening and blade sharpness detection system of claim 8 wherein the support structure has first and second opposed walls separated by a guidance and sensing channel, wherein the optical inspection unit is in optical communication with the guidance and sensing channel, and wherein the pairs of spheres of the blade positioning and guidance mechanism are disposed within the guidance and sensing channel spaced from the optical inspection unit.
10. The blade sharpening and sharpness detection system of claim 1 further comprising a user input to permit a user to input a selected sharpening characteristic wherein the optical inspection unit is operative to detect whether the blade meets the selected sharpening characteristic when inspected by the optical inspection unit.
11. A blade sharpness detection system for permitting a determination of a sharpness of a blade, the system comprising: a housing; an optical inspection unit retained by the housing wherein the optical inspection unit is operative to inspect blade sharpness optically and wherein the optical inspection unit comprises a light source and an optical sharpness sensor operative to acquire light reflected from the blade whereby reflected light intensity can be converted to a measurement of blade sharpness; and a blade positioning and guidance mechanism retained by the housing wherein the blade positioning and guidance mechanism is disposed to position and guide the blade in relation to the optical inspection unit; wherein the optical inspection unit and the blade positioning and guidance mechanism are retained by a pivotable support structure within the housing; wherein the positioning and guidance mechanism comprises first and second rotatable spheres disposed in a pair with the first rotatable sphere disposed in immediate juxtaposition to the second rotatable sphere and with the first and second rotatable spheres spaced from the optical inspection unit.
12. The blade sharpness detection system of claim 11 further comprising an output display operative to provide a visual output of the sharpness of the blade in a localized position.
13. The blade sharpness detection system of claim 11 wherein the pivotable support structure is pivotable about a pivot axis in relation to a pivot support cradle.
14. The blade sharpness detection system of claim 11 wherein the support structure has first and second opposed walls separated by a guidance and sensing channel, wherein the optical inspection unit is in optical communication with the guidance and sensing channel, and wherein the blade positioning and guidance mechanism is disposed within the guidance and sensing channel spaced from the optical inspection unit.
15. The blade sharpness detection system of claim 11 wherein the optical inspection unit comprises a reflective optical sensor.
16. The blade sharpness detection system of claim 11 wherein the blade positioning and guidance mechanism further comprises first and second pairs of rotatable spheres, wherein the spheres of each pair of rotatable spheres are in immediate juxtaposition, and wherein the pairs of rotatable spheres are retained in spaced relation to one another and in relation to the optical inspection unit.
17. The blade sharpness detection system of claim 16 wherein the pairs of spheres are disposed in corresponding positions distally and laterally spaced from the optical inspection unit whereby the optical inspection unit is centered between and proximal to the pairs of spheres.
18. The blade sharpness detection system of claim 17 wherein the support structure has first and second opposed walls separated by a guidance and sensing channel, wherein the optical inspection unit is in optical communication with the guidance and sensing channel, and wherein the pairs of spheres of the blade positioning and guidance mechanism are disposed within the guidance and sensing channel spaced from the optical inspection unit.
19. The blade sharpness detection system of claim 11 further comprising a user input to permit a user to input a selected sharpening characteristic wherein the optical inspection unit is operative to detect whether the blade meets the selected sharpening characteristic when inspected by the optical inspection unit.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) In the accompanying drawing figures:
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DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
(26) The systems for blade sharpening and contactless blade sharpness detection disclosed herein are subject to a wide variety of embodiments. However, to ensure that one skilled in the art will be able to understand and, in appropriate cases, practice the present invention, certain preferred embodiments of the broader invention revealed herein are described below and shown in the accompanying drawing figures.
(27) The systems for blade sharpening and contactless blade sharpness detection disclosed herein may be employed to great advantage where blade sharpening and blade sharpness detection are enabled in a single device. However, it is to be understood that contactless blade sharpness detection systems according to the invention could be employed independently and that the present blade sharpening system could be exploited in combination with differently embodied blade sharpness detection systems or vice versa. The scope of the invention shall be limited only as may be expressly required by the claims. Before any particular embodiment of the invention is explained in detail, it must be made clear that the following details of construction and illustrations of inventive concepts are mere examples of the many possible manifestations of the invention.
(28) Turning more particularly to the drawings, a system for blade sharpening and contactless blade sharpness detection according to the present invention is indicated generally at 10 in
(29) The blade sharpening mechanism can be understood with additional reference to
(30) The coarse sharpening wheel 30, which is typical of the fine sharpening wheel 32 and the polishing wheel 34 except for the blade finishing characteristics required for coarse sharpening, fine sharpening, or polishing, respectively, is shown apart in
(31) The supports of the sharpening wheel support structure 42 are disposed to retain the coarse grinding wheel 30, the fine grinding wheel 32, and the polishing wheel 34 at non-zero, acute angles in relation to a longitudinal of the housing 12 while the housing 12 has corresponding slots 18, 20, and 22 that communicate laterally across the housing 12. More particularly, a coarse grinding slot 18 traverses laterally across the housing 12 overlying the angled coarse grinding wheel 30, a fine grinding slot 20 traverses laterally across the housing 12 overlying the angled fine grinding wheel 32, and a polishing slot 22 traverses laterally across the housing 12 overlying the angled polishing wheel 34.
(32) The optical inspection unit 26 and the blade positioning and guidance mechanism 28 are retained by the detection system support structure 54 of the framework 25 and can be further understood with additional reference to
(33) The optical inspection unit 26 is retained by the pivotable support block 46 to pivot therewith. More particularly, in the present embodiment as shown in
(34) In one embodiment, the optical inspection unit 26 comprises a reflective optical sensor with an optical pair comprising an infrared emitter and a phototransistor photodetector to provide an evaluation of the sharpness of a localized portion of a blade 100. While in the embodiment depicted in, for instance,
(35) Sharpness can be estimated based on a measurement of light power that is acquired by a photo receiver of the optical inspection unit 26 with a single sensitive area, such as a photodiode photo transistor or other system for measuring light power to provide an integral estimation of sharpness. The optical response from the optical inspection unit 26 is directed to the electronic analog or digital processing circuit 58. The processing circuit 58 can include or be electronically connected to a computer processor, which can make a determination regarding blade sharpness based on light power reflected by the blade 100.
(36) It is further contemplated that the optical inspection unit 26 can comprise an image-sensing camera with matched optics to collect video images of a cutting edge of a blade 100 that is supported and guided as disclosed herein and moved by a user. Acquired data regarding blade sharpness acquired by the camera can be derived from the camera image stream in combination with a computerized image processing program, and the acquired data can be retained in electronic memory. A detailed evaluation of sharpness over the continuous evaluated length of a blade 100 can be acquired, stored, and analyzed based on linear position along the blade 100. The detailed evaluation of sharpness can include facet angles, local cutting edge defects, and other details.
(37) To comprehend the operation of the optical inspection unit 26, the computer processing circuit 58, and the sharpening and sharpness detection system 10 in general, a further review of the characteristics of a cutting blade 100 and the optical interaction between the cutting blade 100 and the optical inspection unit 26 would be assistive. With reference to
(38) When the cutting edge is illuminated by a collimated light bundle, such as that indicated at 68 in
(39) The relative amount of light received by optical sharpness sensor 26 depends on the radius of the cutting edge and the surface roughness of the edges of the blade 100. As can be understood with reference to
(40) As set forth above, the sharpening and sharpness detection system 10 could be induced into operation automatically, such as by the insertion of a blade 100, or it could be actuated by the pressing of a power button 24, which can be electrically associated with a printed circuit board 24 for the power button 24. The sharpening and sharpness detection system 10 could be powered by a battery pack 55 or, potentially, by alternating current from a source of electric power. As in
(41) For the optical sharpness sensor 26 to operate reliably, the position of the blade 100 in relation to the sensor 26 must be established and maintained in a stable manner. In the depicted embodiments, the blade 100 is stably positioned and guided during movement in relation to the optical sharpness sensor 26 by the blade positioning and guidance mechanism 28. The positioning and guidance mechanism 28 accurately positions and guides the blade 100 in relation to the optical sharpness sensor 26 while permitting the avoidance of mechanical contact between the actual cutting edge of the blade 100 and the positioning and guidance mechanism 28 once the blade 100 is fully inserted into the positioning and guidance mechanism 28.
(42) Referring to
(43) As shown in
(44) Under this construction, a blade 100 can be inserted into the progressively narrowing spaces between the pairs of spheres of the positioning and guidance mechanism 28. As a result of the geometry of the spheres and with respect to any available cutting edge angle, the blade 100 will contact the spheres at two points along the facets 102 proximal to the actual cutting edge of the blade 100. The cutting edge of the blade 100 projects beyond the points of contact between the facets 102 and the spheres and does not touch the hard surfaces of the spheres once the blade 100 is fully inserted. With that, the sharpness of the blade 100 can be detected with the blade 100 being maintained at a known and consistent position with respect to the optical sharpness sensor 26. Because the points of mechanical contact of the blade facets 102 with the rigid spheres are very small, the pressure at these contact spots is relatively large, and there is possibility of additional hardening of the cutting edge due to elastic deformation and cold hardening of the blade material.
(45) Not only do the spheres of the positioning and guidance mechanism 28 establish a known controlled position and orientation of the blade 100 in relation to the optical sharpness sensor 26, but they also permit movement of the blade 100 along a longitudinal of the blade 100. By virtue of their ability to rotate as facilitated by the rolling bearing assemblies 72, the spheres act as rolling supports to the blade 100 as it is repositioned longitudinally. Because the actual cutting edge is free of contact with the positioning and guidance mechanism 28 once the blade 100 is in position, damage to even a very sharp edge during the measurement process is prevented, including during relative movement between the blade 100 and the optical sharpness sensor 26.
(46) Moreover, it is contemplated that embodiments of the sharpening and sharpness detection system 10 could carry out at least some sharpening of the blade 100 based on the contact between the blade at the points of contact of the blade and the rigid spheres. For instance, where the spheres have a high hardness, such as in the range of approximately 65-70 HRC, further blade sharpening may be realized. In certain non-limiting embodiments, the material of the spheres could comprise Al2O3 ceramic, sapphire crystal, carbide ceramic, super hard cobalt alloys, or other hard alloys, ceramics, or crystals.
(47) It will again be noted that the optical inspection unit 26 and the blade positioning and guidance mechanism 28 are mounted to the support block 46, which in turn is retained to pivot about a pivot axis 60 in relation to the fixed support cradle 44. As a result, over a given range of pivoting, the support block 46 can pivot to engage a blade 100 fully or to pivot with a blade 100 that may be tilted in relation to the sharpening and sharpness detection system 10, such as during longitudinal movement of the blade 100 in relation to the support block 46 and the optical inspection unit 26.
(48) An output of the sharpness of the blade 100 as sensed by the optical inspection unit 26 can be provided by the output display 16 or any other data displaying or data recording or presenting system. For instance, the output display 16 can provide a visual output of the sharpness of the blade 100 as sensed by the optical inspection unit 26. Output could be provided as an indication of a sharpness of a local position of a blade 100. For instance, the output display 16 can indicate the sensed sharpness of the local portion of the blade then positioned to be inspected by the optical inspection unit 26.
(49) By operation of the rolling support provided by the blade positioning and guidance mechanism 28, the blade 100 can be positioned and adjusted in position longitudinally in relation to the optical inspection unit 26 to provide specific indications to the user of the sharpness of each location along the blade 100. For instance, as shown in
(50) The optical inspection unit 26 and the output display 16 can also provide progressive indications of the sharpness of the blade 100 during stages of sharpening using the integrated blade sharpening mechanism formed in this example by the coarse sharpening wheel 30, the fine sharpening wheel 32, and the polishing wheel 34. For instance, as in
(51) Additionally or alternatively, output could be provided, such as in a chart, wave, or other format or report, of sensed sharpness based on position along a blade 100. For example, where a blade 100 has been caused to translate longitudinally in relation to the optical inspection unit 26, electronic data regarding blade sharpness over the length of the blade 100 could be obtained and recorded in electronic memory, and a report charting that sharpness based on blade location can be output, such as by a computer display, by a visual display 16 on the housing, by a printed report, or by any other method. The user can thus be apprised of particular locations along the blade 100 that require specific attention and those locations that are already sufficiently prepared.
(52) The type of output to indicate sensed blade sharpness could vary within the scope of the invention. The output could be a visually-perceptible output display 16 as shown, an audible output, or any other output. For instance, the output display 16 could be embodied as a qualitative visual display, such as a series of light-emitting diodes, an illuminated lightpipe, or any other qualitative visual display providing a visual indication dependent on the sensed sharpness of the blade 100. In the depicted example, the output display 16 comprises a lightpipe with a qualitative display wherein the higher the illuminated portion of the display the higher the sharpness of the blade 100. The output display 16 could additionally or alternatively be color coded, such as by having a red indication indicative of a dull blade with progressive changes in color coding until a green display indicative of ideal sharpness is achieved. Textual markings, gradations, or other indications adjacent to the output display 16 can provide indications of the meaning of the display. The output display 16 is electronically coupled with a printed circuit board 50, which is in turn supported by posts 48 that are supported by the bottom 36 of the system 10. Other output displays 16 could include, but not be limited to, numerical displays, dial gauges, or any other type of output display 16 capable of presenting or conveying the acquired sharpness data.
(53) It is also contemplated that the sharpening and sharpness detection system 10 could be adjustable with respect to the blade sharpening angles, blade sharpness levels, or otherwise to accommodate different blade types and different user goals. For instance, the optical sharpness sensor 26 and the associated computer circuitry, the output display 16, and, additionally or alternatively, other components of the system 10 could be adjustable to provide different levels of optical signal characteristics to permit the user to select the type of blade 100 to be sharpened, such as a butcher knife as compared to a pairing knife as compared to a hunting knife, to receive a particularized level of accuracy in the output display 16 or other output based on the sharpness of the blade 100 in relation to the selected setting.
(54) The blade sharpening and sharpness detection system 10 can also permit a user to input a known sharpness angle or other sharpening characteristic, and software operating in relation to the blade sharpening and sharpness detection system 10 can provide sharpening through the integrated blade sharpening mechanism and, additionally or alternatively, output, such as through the output display 16 or otherwise to provide an indication of the condition of the blade 100 in comparison to the predetermined input sharpening characteristic. For instance, a given indication, such as a color-coded, scale-oriented, or other indication, can be given when the blade 100 is not found by the optical sharpness sensor 26 and the computer software to meet the input sharpening characteristic, and a different indication can be given when the blade 100 is found to meet the input sharpening characteristic. A non-limiting example of such an embodiment is depicted in
(55) It is recognized that, within the blade sharpening and sharpness detection system 10, there may be a change in optical signal between blades 100 of corresponding sharpness but with different cutting edge angles. The software algorithm operating on the system 10 is coded to correct for the foregoing. Moreover, the software algorithm is coded to accommodate any phenomenon where reflected light varies non-linearly in comparison to blade sharpness. The system 10 can thus readily provide an accurate sharpness progress indication with respect to blades 100 sharpened at, for instance, fifteen-degree angles and twenty-five degree angles even where the optical signal levels provided by those angles is different, and the system 10 can provide accurate indications of sharpness even where the reflected light returned to the optical sharpness sensor 26 does not vary linearly with changes in sharpness.
(56) Using the blade sharpening and sharpness detection system 10, a user is thus enabled to sharpen a blade 100 by use of the integrated blade sharpening mechanism while also being able to test and be apprised of the current sharpness of the blade 100 by use of the optical sharpness sensor 26 and the output display 16. Furthermore, in certain embodiments, such as where a camera is used as all or a component of the optical sharpness sensor 26, video can be obtained and stored in electronic memory of blade sharpness dependent on linear position along the cutting edge of the blade 100. For example, a user can insert the blade 100 into position contacting both sets of spheres of the positioning and guidance mechanism 28 to ensure that proper positioning of the blade 100 is achieved. The sharpening and sharpness detection system 10 can be automatically triggered into operation or actuated as by a pressing of the power button 24 to cause a sensing of the localized sharpness of the blade 100. The blade 100 can be manually moved over the optical sharpness sensor 26 so that sharpness along the length of the blade 100 can be sensed and, as necessary, acted upon by the user through further blade processing using the integrated blade sharpening mechanism. In certain practices of the invention, the contactless optical sharpness sensor 26 can produce a video stream with multiple image frames of the illuminated cutting edge of the blade 100 to be measured. Additionally or alternatively, the system 10 can provide an analog optical response signal that is inversely proportional to the cutting edge sharpness of the illuminated portion of the blade 100. The analog signal can be amplified and processed with an analog circuit to produce a control signal for the display. The video stream can be sent to a processor for online or offline processing or stored for later processing. An image processing algorithm is used within one of the electronic processors of the invention to compute the parameters of edge sharpness, such as the cutting angle of the blade 100, edge sharpness, blade defects, and the roughness of the cutting facets 102. The analog signal can be compared with predetermined data to provide a comparative and, additionally or alternatively, a qualitative estimate of blade sharpness. The data about the cutting edge sharpness can be sent to an output display or for storage or processing. Based on the results and the output of the sharpness testing, a user can continue a given stage of sharpening or move to a finer sharpening stage or consider the sharpening process to be complete.
(57) With certain details and embodiments of the present invention for systems for blade sharpening and contactless blade sharpness detection disclosed, it will be appreciated by one skilled in the art that changes and additions could be made thereto without deviating from the spirit or scope of the invention. This is particularly true when one bears in mind that the presently preferred embodiments merely exemplify the broader invention revealed herein. Accordingly, it will be clear that those with certain major features of the invention in mind could craft embodiments that incorporate those major features while not incorporating all of the features included in the preferred embodiments. The invention shall not be limited with respect to any dimensions, relative size relationships, notations, or particular configurations shown or described herein except as expressly required by the claims.
(58) Therefore, the following claims are intended to define the scope of protection to be afforded to the inventors. Those claims shall be deemed to include equivalent constructions insofar as they do not depart from the spirit and scope of the invention. It must be further noted that one or more of the following claims could express certain elements as means for performing a specific function, at times without the recital of structure or material. As the law demands, any such claims shall be construed to cover not only the corresponding structure and material expressly described in this specification but also all equivalents thereof that might be now known or hereafter discovered.