The present invention relates to a magnetic chuck (magnet chuck) that attracts and holds a workpiece by means of a force of a permanent magnet.
Magnetic chucks are conventionally known in which a permanent magnet is joined to a piston inside a cylinder and displaced together with the piston (for example, refer to Japanese Laid-Open Utility Model Publication No. 51-102174). In such a magnetic chuck, as the piston is displaced by a fluid pressure, the permanent magnet comes close to the workpiece and attracts and holds the workpiece. The workpiece is released when the piston is displaced in the direction away from the workpiece.
Attracting a heavy workpiece with a magnetic chuck requires an increased attracting force, but increasing the attracting force is not easy if the workpiece is a thin plate, because magnetic saturation occurs inside the workpiece. Further, simply choosing a permanent magnet having a large magnetic force leads to an increase in size of the device.
The applicant of the present invention has proposed a technique for configuring a magnetic chuck using a permanent magnet so that an increased magnetic flux passes in the workpiece to exert a larger attracting force on the workpiece (refer to Japanese Laid-Open Patent Publication No. 2016-124096). In the magnetic chuck, a plurality of permanent magnets are arranged in such a manner that one or more sets of a north pole and a south pole exist at the surface that faces the workpiece.
For magnetic chucks using permanent magnets, it is desirable to further increase the magnetic flux passing in the workpiece so as to hold the workpiece with as large an attracting force as possible. It is also desirable to obtain useful means for detecting operating conditions of the magnetic chuck.
The present invention has been devised considering such circumstances, and an object of the present invention is to provide a magnetic chuck capable of attracting and holding a workpiece with as large a magnetic attraction force as possible. Another object is to provide a magnetic chuck capable of detecting operating conditions, such as the position of the piston, presence/absence of a workpiece, etc., using a simple configuration.
The present invention provides a magnetic chuck in which a piston assembly including a tubular permanent magnet and a core yoke is provided movably inside a cylinder tube, wherein the permanent magnet is provided around the core yoke and is magnetized in a radial direction, and a magnetic sensor configured to detect a magnetic flux of the permanent magnet is attached to a side surface of the cylinder tube.
According to the magnetic chuck above, the core yoke as a ferromagnetic body is disposed on the side of the inner periphery of the permanent magnet, so that the magnetic flux from the permanent magnet can be concentrated to increase the magnetic attraction force acting on the workpiece. Furthermore, the magnetic sensor attached to a side surface of the cylinder tube can detect the magnetic flux that varies with the movement of the permanent magnet and presence/absence of a workpiece, whereby operating conditions of the magnetic chuck can be detected using a simple configuration.
In the magnetic chuck configured as described above, preferably, a cover yoke is provided around the permanent magnet. Then, a magnetic flux density having a suitable magnitude for causing the magnetic sensor to respond is obtained in the side surface of the cylinder tube to which the magnetic sensor is attached.
The magnetic sensor may be attached so as to be capable of detecting a position of the piston assembly, or so as to be capable of detecting whether the magnetic chuck is attracting and holding a workpiece.
Preferably, an outer yoke that faces an outer periphery of the piston assembly at a movement end of the piston assembly is provided at one end in an axial direction of the cylinder tube. This configuration further increases the magnetic attraction force acting on the workpiece. Furthermore, at the movement end of the piston assembly, the magnetic attraction force acting between the outer yoke and the piston assembly is weakened, and therefore the air pressure required to move the piston assembly from the movement end can be made smaller.
Preferably, a bottom yoke that faces the core yoke is provided at one end in the axial direction of the cylinder tube, in which case, preferably, the bottom yoke fits into a recess of the core yoke at the movement end of the piston assembly. This configuration further increases the magnetic attraction force acting on the workpiece. Furthermore, at the movement end of the piston assembly, the magnetic attraction force acting between the bottom yoke and the piston assembly is weakened, and therefore the air pressure required to move the piston assembly from the movement end can be made smaller.
Preferably, a latch yoke that faces the piston assembly is provided at another end in the axial direction of the cylinder tube. According to this configuration, at a movement end that is opposite to the above-mentioned movement end, the piston assembly is attracted by the latch yoke with a certain magnetic attraction force, which eliminates the fear that the piston assembly might unexpectedly move and attract the workpiece. Furthermore, in the transportation of the magnetic chuck, for example, it is possible to avoid the situation in which the magnetic chuck unexpectedly attracts neighboring iron materials etc., which ensures safety.
According to the magnetic chuck of the present invention, the core yoke, as a ferromagnetic body, is provided on the side of the inner periphery of the permanent magnet, and therefore the magnetic flux from the permanent magnet can be concentrated and the magnetic attraction force acting on the workpiece can be increased. Furthermore, the magnetic sensor attached to a side surface of the cylinder tube can detect the magnetic flux that varies with the movement of the permanent magnet and presence/absence of a workpiece, whereby the operating conditions of the magnetic chuck can be detected using a simple configuration.
The magnetic chuck according to the present invention will be described referring to the accompanying drawings in connection with preferred embodiments.
A magnetic chuck 10 includes a cylinder tube 12, a piston assembly 14, a top cover 16, a bottom cover 18, and a latch yoke 20. The magnetic chuck 10 is attached to an end arm of a robot not shown, for example.
The cylinder tube 12 is made of a paramagnetic metal such as an aluminum alloy. The cylinder tube 12, except a fitting portion 22 formed at the lower end of the cylinder tube 12, has a rectangular outline in transverse section, and the cylinder tube 12 hence has four side surfaces. The fitting portion 22 of the cylinder tube 12 has a circular outline in transverse section. The cylinder tube 12 has a cylinder hole 24 having a circular cross section and passing through the cylinder tube 12 along its axial direction.
A first port 26 for supplying and discharging air is formed in one side surface of the cylinder tube 12. The first port 26 connects to the upper end of a first air supply/discharge hole 28 extending inside the wall of the cylinder tube 12 along the axial direction. As shown in
Two attachment grooves 34 are formed in the side surface of the cylinder tube 12 in which the first port 26 opens and in the opposite side surface of the cylinder tube 12. The attachment grooves 34 extend along the axial direction of the cylinder tube 12 to reach both upper and lower ends thereof, and a magnetic sensor 36 is attached in one of the attachment grooves 34.
The magnetic sensor 36 is configured as a contactless switch that detects a difference between the magnetic flux density along the longitudinal direction of the attachment groove 34 and the magnetic flux density along a direction that is orthogonal to the longitudinal direction and passes through the center axis line of the cylinder hole 24. The magnetic sensor 36 is attached in a certain position in the longitudinal direction of the attachment groove 34 so that it can detect the position of the piston assembly 14 or detect whether a workpiece is present or absent. The position in which the magnetic sensor 36 is attached will be described in detail later.
The end of the fitting portion 22 of the cylinder tube 12 has a step in which a third seal member 96, described later, is fitted. The top end of the cylinder hole 24 has a step 32 on which the latch yoke 20 is mounted. The four corners of the cylinder tube 12, where the side surfaces thereof connect, are made thicker and have insertion holes 35 into which tie rods 94, described later, are inserted.
The piston assembly 14 includes a seal holder 38, a core yoke 40, a permanent magnet 42, a cover yoke 44, and a ring plate 45.
The seal holder 38 is shaped like a disk of a paramagnetic metal such as an aluminum alloy. A piston seal 46 is fitted in a recessed groove formed along the circumference of the seal holder 38, and the piston seal 46 is in sliding contact with the wall surface of the cylinder hole 24. A through hole 48 is formed in the center of the seal holder 38, and an inward flange 50, protruding inwardly from the through hole 48, is formed at the upper end of the seal holder 38. The top surface of the seal holder 38 that faces toward the top cover 16 has a ring-shaped recess 51 formed therein.
The core yoke 40 is shaped like substantially a round pillar of a steel material being a ferromagnetic substance. A small-diameter, tubular protrusion 52 is formed in the center of the upper end of the core yoke 40. The core yoke 40 has a threaded hole 54 having a bottom and opened at the end of the tubular protrusion 52. The lower end of the core yoke 40 has formed therein a recess 56 having a circular cross section and opened downward. A first damper 58 is attached in the bottom surface of the recess 56 so as to somewhat protrude from the bottom surface. When the piston assembly 14 has descended to the bottom dead center, the first damper 58 abuts on a bottom yoke 80 and functions to alleviate the shock (see
The tubular protrusion 52 of the core yoke 40 is fitted in the through hole 48 of the seal holder 38 from below until the tubular protrusion 52 abuts on the inward flange 50 of the seal holder 38, and a fixing screw 60 is put into the through hole 48 from above and inserted and screwed in the threaded hole 54 of the core yoke 40. The seal holder 38 and the core yoke 40 are thus integrally joined together. A first seal member 62 is attached around the base of the tubular protrusion 52 of the core yoke 40. The first seal member 62 provides a seal between the seal holder 38 and the core yoke 40.
The tubular permanent magnet 42 is disposed around the core yoke 40, and is attached thereto so as to be enclosed by the seal holder 38, the core yoke 40, the cover yoke 44, and the ring plate 45. The permanent magnet 42 is magnetized in a radial direction. That is, the permanent magnet 42 has a north pole on its inner peripheral side and a south pole on its outer peripheral side. Alternatively, the south pole may be on the inner peripheral side and the north pole may be on the outer peripheral side. As shown in
The tubular cover yoke 44 is disposed around the permanent magnet 42. The cover yoke 44 is made of a steel material being a ferromagnetic substance. The outer periphery of the cover yoke 44 has a large-diameter upper portion and a small-diameter lower portion. That is, the cover yoke 44 has a large-diameter portion 64 above a step 65 and a small-diameter portion 66 below the step 65. Two annular grooves 68a, 68b, spaced apart in the axial direction, are formed in the large-diameter portion 64. Wear rings 70a, 70b are fitted in the annular grooves 68a, 68b. The piston assembly 14 is guided and supported in the cylinder hole 24 with the wear rings 70a, 70b therebetween.
The top cover 16 is made of a paramagnetic metal such as an aluminum alloy, and is formed in the same rectangular plate shape in plan view as the outline of the cylinder tube 12. The lower surface of the top cover 16 has a circular recess 72 having two step surfaces. That is, the circular recess 72 has a large-diameter portion 72a, a middle-diameter portion 72b, and a small-diameter portion 72c from the side closer to the cylinder tube 12, with a first step surface 72d between the large-diameter portion 72a and the middle-diameter portion 72b, and a second step surface 72e between the middle-diameter portion 72b and the small-diameter portion 72c.
The middle-diameter portion 72b and the second step surface 72e serve to position the latch yoke 20. The small-diameter portion 72c allows the head of the fixing screw 60 to be accommodated therein when the piston assembly 14 rises (see
The top cover 16 has a second port 76 formed therein. One end of the second port 76 opens in the side surface of the top cover 16 that corresponds to the side surface of the cylinder tube 12 where the first port 26 opens. The other end of the second port 76 opens in the second step surface 72e of the top cover 16.
Grooves 78, which match the attachment grooves 34 of the cylinder tube 12, are formed in the side surface of the top cover 16 where the second port 76 opens and in the opposite side surface of the top cover 16. The grooves 78 are used to attach the magnetic sensor 36 in the attachment groove 34 of the cylinder tube 12. Insertion holes 79, into which the tie rods 94 described later are inserted, are formed in the four corners of the rectangle-shaped top cover 16 so as to pass through the top cover 16 in the thickness direction thereof.
The bottom cover 18 includes the bottom yoke 80, an outer yoke 82, a first housing 86, and a second housing 100. The bottom yoke 80 is shaped like a round pillar of a steel material being a ferromagnetic substance. The bottom yoke 80 fits into the recess 56 of the core yoke 40 when the piston assembly 14 descends (see
The outer yoke 82 is disposed around the bottom yoke 80. The outer yoke 82 is shaped like a round tube of a steel material being a ferromagnetic substance. An upper flange 82a, protruding radially outward, is formed at the top of the outer yoke 82, and an outer recess 82b, depressed radially inward, is formed in a lower area of the outer surface of the outer yoke 82. Further, a step 82c is formed at the inner bottom edge of the outer yoke 82.
A ring-shaped joint plate 84 is attached between the bottom flange 80a of the bottom yoke 80 and the step 82c of the outer yoke 82. The outer yoke 82 is thus fixed to the bottom yoke 80. The joint plate 84 is made of a paramagnetic metal such as an aluminum alloy.
The first housing 86 is shaped like a tube of a paramagnetic metal such as an aluminum alloy. The outline of the first housing 86 in transverse section is the same as that of the cylinder tube 12. The first housing 86 has a through hole 88 having a circular transverse section and passing therethrough vertically, and a lower flange 90 protruding inwardly at the bottom of the through hole 88. The fitting portion 22 of the cylinder tube 12 is fitted in the through hole 88 of the first housing 86.
Grooves 92, which match the attachment grooves 34 of the cylinder tube 12, are formed in a pair of opposing side surfaces of the first housing 86, among its four side surfaces. The grooves 92 are used to attach the magnetic sensor 36 in the attachment groove 34 of the cylinder tube 12. Threaded holes 93, into which the tie rods 94 described below are screwed, are formed in the four corners of the first housing 86.
Four tie rods 94 are inserted into the insertion holes 79 of the top cover 16 and the insertion holes 35 of the cylinder tube 12, and the ends of the tie rods 94 are screwed into the threaded holes 93 of the first housing 86. The top cover 16, the cylinder tube 12, and the first housing 86 are thus joined and fixed together. The upper flange 82a of the outer yoke 82 is held between the end surface of the fitting portion 22 of the cylinder tube 12 and the lower flange 90 of the first housing 86, whereby the outer yoke 82 is also joined and fixed therewith.
The third seal member 96 is attached in the gap formed by the step at the end of the fitting portion 22 of the cylinder tube 12 and the top surface of the outer yoke 82. The third seal member 96 provides a seal between the cylinder tube 12 and the outer yoke 82.
A ring-shaped second damper 98 is attached in a position that faces the ring-shaped recess 30 of the cylinder tube 12 and that is between the bottom of the cylinder tube 12 and the top surface of the outer yoke 82. When the piston assembly 14 has descended to the bottom dead center, the second damper 98 abuts on the step 65 of the cover yoke 44 and functions to alleviate the shock. As shown in
The second housing 100 is made of a resin material or rubber material, and fitted and attached in the outer recess 82b of the outer yoke 82. The second housing 100 slightly protrudes downward beyond the bottom yoke 80 and the outer yoke 82. Accordingly, when the second housing 100 comes in contact with an iron plate (workpiece) W that is to be attracted, a small gap is formed between the plate W, and the bottom yoke 80 and outer yoke 82.
The latch yoke 20 is shaped like a disk of a steel material being a ferromagnetic substance, and is disposed in the circular recess 72 of the top cover 16 and on the step 32 of the top edge of the cylinder hole 24. The latch yoke 20 has a central through hole 102 formed in its center to pass therethrough vertically. The top end of the central through hole 102 forms a small-diameter portion 102a that matches the small-diameter portion 72c of the top cover 16, and that can accommodate the head of the fixing screw 60 when the piston assembly 14 rises (see
The top surface of the latch yoke 20 has a ring-shaped groove 108 formed therein (see
The space in the cylinder tube 12 is divided into a first pressure chamber 112 existing below the piston seal 46 of the seal holder 38 and a second pressure chamber 114 existing above the piston seal 46 of the seal holder 38. The first port 26 communicates with the first pressure chamber 112 through the first air supply/discharge hole 28 and the slits 98a of the second damper 98, and the second port 76 communicates with the second pressure chamber 114 through the ring-shaped groove 108 and the second air supply/discharge holes 110 of the latch yoke 20.
The magnetic chuck 10 of the embodiment is constructed basically as explained above. Next, functions of the magnetic chuck 10 will be described mainly referring to
A large number of the magnetic flux lines coming out from the inner side of the permanent magnet 42, which is the north pole, pass through the core yoke 40, the latch yoke 20, and the cover yoke 44, and return to the outer side of the permanent magnet 42 that is the south pole. On the other hand, there are few magnetic flux lines that return to the permanent magnet 42 via the bottom yoke 80 or the outer yoke 82 that are spaced apart from the permanent magnet 42. The piston assembly 14 including the permanent magnet 42 is attracted by the latch yoke 20 by a certain magnetic attraction force.
During transportation before the magnetic chuck 10 is brought into use, for example, the piston assembly 14 is held in the position of top dead center by the function of the latch yoke 20, even though no air is being supplied to the magnetic chuck 10. It is thus possible to avoid the unexpected situation in which the magnetic chuck 10 attracts neighboring iron materials etc., which ensures safety.
In the initial state, a robot not shown, for example, is driven to bring the magnetic chuck 10 close to the iron plate (workpiece) W to be attracted, and the second housing 100 is made to abut on the plate W. At the same time, a selector valve (not shown) is operated to supply air into the second pressure chamber 114 from the second port 76, and discharge the air in the first pressure chamber 112 from the first port 26.
The force to drive the piston assembly 14 downward by the differential pressure between the second pressure chamber 114 and the first pressure chamber 112 exceeds the magnetic attraction force acting between the latch yoke 20 and the piston assembly 14 at the top dead center of the piston assembly 14, causing the piston assembly 14 to start descending.
As the piston assembly 14 descends, the magnetic attraction force acting between the latch yoke 20 and the piston assembly 14 gradually becomes smaller, while the magnetic attraction force acting between the bottom yoke 80 or outer yoke 82 and the piston assembly 14 becomes larger gradually. When the latter magnetic attraction force exceeds the former magnetic attraction force, then the force to cause the piston assembly 14 to descend becomes the force based on the differential pressure between the first pressure chamber 112 and the second pressure chamber 114 plus the difference between the latter magnetic attraction force and the former magnetic attraction force.
A large number of the magnetic flux lines coming out from the inner side of the permanent magnet 42 return to the outer side of the permanent magnet 42 at least through the bottom yoke 80 or the outer yoke 82. On the other hand, few magnetic flux lines return to the permanent magnet 42 through the latch yoke 20. The magnetic flux lines returning to the permanent magnet 42 through the bottom yoke 80 or the outer yoke 82 mainly include three paths below.
The first path comes out from the permanent magnet 42, passes sequentially through the core yoke 40, the bottom yoke 80, the plate W, the outer yoke 82, and the cover yoke 44, and returns to the permanent magnet 42. The second path comes out from the permanent magnet 42, passes sequentially through the core yoke 40, the bottom yoke 80, the outer yoke 82, and the cover yoke 44, and returns to the permanent magnet 42. The third path comes out from the permanent magnet 42, passes sequentially through the core yoke 40, the outer yoke 82, and the cover yoke 44, and returns to the permanent magnet 42. The plate W is included in the first path and hence experiences the magnetic attraction force from the magnetic chuck 10.
As the piston assembly 14 further descends, the bottom yoke 80 fits into the recess 56 of the core yoke 40. Then, the step 65 of the cover yoke 44 abuts on the second damper 98, and the first damper 58 abuts on the bottom yoke 80, whereby the piston assembly 14 reaches the bottom dead center (bottom end).
As can be understood from the diagrams, when the piston assembly 14 is in the vicinity of the bottom dead center, most of the magnetic flux lines coming out from the permanent magnet 42 and returning to the permanent magnet 42 pass sequentially through the core yoke 40, the bottom yoke 80, the plate W, the outer yoke 82, and the cover yoke 44.
More specifically, the magnetic flux lines coming out from the inner peripheral surface of the permanent magnet 42 pass through the inside of the core yoke 40 or the bottom yoke 80 while changing their directions downward, and enter the plate W while increasing the magnetic flux density. Then, the magnetic flux lines come out upward from the plate W and pass through the outer yoke 82 and the cover yoke 44, and then return to the outer peripheral surface of the permanent magnet 42. An increased magnetic flux density of the magnetic flux lines entering the plate W means a larger magnetic attraction force acting on the plate W. The magnetic flux density passing through the plate W becomes maximum when the piston assembly 14 is at bottom dead center, and so the plate W is attracted and held by the magnetic chuck 10 with the maximum magnetic attraction force.
Now, when the piston assembly 14 is at bottom dead center, a large number of the magnetic flux lines coming out from the core yoke 40 and entering the bottom yoke 80 extend in substantially a horizontal direction from the wall surface of the recess 56 of the core yoke 40. The horizontal components of the magnetic flux lines cancel out in the entire circumferential direction and does not contribute to the magnetic attraction force acting between the core yoke 40 and the bottom yoke 80. Further, most of the magnetic flux lines coming out from the outer yoke 82 and entering the cover yoke 44 extend in substantially a horizontal direction in the small-diameter portion 66 of the cover yoke 44. The horizontal components of the magnetic flux lines cancel out in the entire circumferential direction and does not contribute to the magnetic attraction force acting between the cover yoke 44 and the outer yoke 82. That is, in the vicinity of the bottom dead center of the piston assembly 14, the outer yoke 82 faces the piston assembly 14, including the cover yoke 44, on the outer peripheral side of the piston assembly 14, and the bottom yoke 80 fits into the recess 56 of the core yoke 40, which weakens the force by which the piston assembly 14 is attracted by the bottom yoke 80 and the outer yoke 82.
With the magnetic chuck 10 attracting and holding the plate W at the bottom dead center position of the piston assembly 14, the plate W is conveyed to a given position. Then, in order to release the plate W, a selector valve (not shown) is operated to supply air into the first pressure chamber 112 from the first port 26 and discharge the air in the second pressure chamber 114 from the second port 76.
The force to drive the piston assembly 14 upward by the differential pressure between the first pressure chamber 112 and the second pressure chamber 114 exceeds the magnetic attraction force that acts between the bottom yoke 80 and the outer yoke 82, and the piston assembly 14 at and near the bottom dead center of the piston assembly 14, and then the piston assembly 14 rises. As stated above, the magnetic attraction force acting between the bottom yoke 80 and the outer yoke 82, and the piston assembly 14 in the vicinity of the bottom dead center of the piston assembly 14 is weakened, and therefore the air pressure required to raise the piston assembly 14 can be made smaller accordingly.
The rise of the piston assembly 14 is stopped when the inward flange 50 of the seal holder 38 abuts on the third damper 104. That is, the piston assembly 14 reaches the top dead center. The magnetic attraction force acting on the plate w gradually becomes smaller in the course of the rising motion of the piston assembly 14, and the plate W is thus freed from the attraction. The piston assembly 14 is reliably held in the position of the top dead center because the differential pressure between the first pressure chamber 112 and the second pressure chamber 114 continuously acts in addition to the effect of the latch yoke 20. This eliminates the fear that the piston assembly 14 might descend unexpectedly and attract the plate W.
As can be seen from
On the other hand,
Next, referring to
In the description below, the absolute value of the magnetic flux density along the longitudinal direction of the attachment groove 34 will be referred to as “axial-direction magnetic flux density” and the absolute value of the magnetic flux density along the direction orthogonal to the longitudinal direction of the attachment groove 34 and passing through the center axis of the cylinder hole 24 will be referred to as “radial-direction magnetic flux density”. Simply saying “magnetic flux density” denotes the difference between the “axial-direction magnetic flux density” and “radial-direction magnetic flux density”.
As shown in
Considering this situation, in order to detect that the piston assembly 14 has risen to a position closer to the top dead center than to the bottom dead center, i.e., that the piston assembly 14 is being pulled up, the magnetic sensor 36 is attached in a position approximately from 45 to 52 mm.
As can be seen from
According to the embodiment, the core yoke 40, as a ferromagnetic body, is provided on the side of the inner periphery of the permanent magnet 42, and therefore the magnetic flux from the permanent magnet 42 can be concentrated and the magnetic attraction force acting on the plate W can be increased. Further, the magnetic sensor 36 is attached in a certain position along the longitudinal direction of the attachment groove 34 formed in the side surface of the cylinder tube 12, and it is therefore possible to detect the position of the piston assembly 14 or detect whether a plate W is present or absent.
In the embodiment, one of the magnetic sensor 36 for detecting the position of the piston assembly 14 or the magnetic sensor 36 for detecting whether a plate W is present or absent is attached using only one of the plurality of attachment grooves 34. However, both of the magnetic sensor 36 for detecting the position of the piston assembly 14 and the magnetic sensor 36 for detecting whether a plate W is present or absent may be attached using two attachment grooves 34.
The magnetic chuck of the present invention is not limited to the embodiments described above, but can of course adopt various configurations without departing from the essence and gist of the present invention.
Number | Date | Country | Kind |
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2018-073232 | Apr 2018 | JP | national |
Filing Document | Filing Date | Country | Kind |
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PCT/JP2019/013305 | 3/27/2019 | WO |
Publishing Document | Publishing Date | Country | Kind |
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WO2019/194050 | 10/10/2019 | WO | A |
Number | Name | Date | Kind |
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3079191 | Engelsted et al. | Feb 1963 | A |
20160189844 | Yajima et al. | Jun 2016 | A1 |
20170011832 | Natti | Jan 2017 | A1 |
Number | Date | Country |
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51-102174 | Aug 1976 | JP |
2016-41622 | Mar 2016 | JP |
2016-124096 | Jul 2016 | JP |
2017-509144 | Mar 2017 | JP |
WO 2016113457 | Jul 2016 | WO |
Entry |
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Indian Office Action dated Jul. 14, 2021 in Indian Patent Application No. 202047047701 (with English translation), 5 pages. |
International Search Report dated Jun. 11, 2019 in PCT/JP2019/013305 filed on March 27, 2019, 2 pages. |
Extended European Search Report dated Dec. 17, 2021 in European Patent Application No. 197817273, 10 pages |
Number | Date | Country | |
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20210101236 A1 | Apr 2021 | US |