JOINT FOR A DEVICE MOVEABLE IN VACUUM, MECHANISM FOR MOVING A DEVICE IN VACUUM AND DEVICE
20230323913 · 2023-10-12
Inventors
Cpc classification
F16C2300/62
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F16C11/12
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F16C11/04
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
Abstract
The present invention relates to a joint for a device moveable in vacuum, the joint comprising a supporting part, a mobile part and a guiding and connecting part, wherein the mobile part and the supporting part each have at least a region of convex shape, with the regions of convex shape of the mobile part and of the supporting part facing one another and with the guiding and connecting part being arranged, in particular clamped, between the regions of convex shape of the supporting part and of the mobile part, wherein the guiding and connecting part has a greater bending elasticity than either of the supporting part and the mobile part. The invention further relates to a mechanism for moving a device in vacuum, the mechanism comprising a plurality of joints and to a device comprising a plurality of joints and/or a mechanism, with the device being configured to be moved in a vacuum.
Claims
1.-30. (canceled)
31. A joint for a device moveable in vacuum, the joint comprising a supporting part, a mobile part and a guiding and connecting part, wherein the mobile part and the supporting part each have at least a region of convex shape, with the regions of convex shape of the mobile part and of the supporting part facing one another and with the guiding and connecting part being arranged, between the regions of convex shape, wherein the guiding and connecting part has a greater bending elasticity than either of the supporting part and the mobile part and the guiding and connecting part has a reduced thickness in comparison to the supporting part and the mobile part, and wherein the mobile part can move relative to the supporting part.
32. The joint in accordance with claim 31, wherein the region of convex shape of at least one of the mobile part and the supporting part has an arcuate shape.
33. The joint in accordance with claim 31, wherein the respective region of convex shape of the mobile part and of the supporting part is formed by bending a respective first part of the region of convex shape relative to a second part of the region of convex shape, with the bend being selected in the range of 10 to 80°.
34. The joint in accordance with claim 31, wherein the region of convex shape of the mobile part and of the supporting part is formed such that the mobile part and the supporting part each have a surface forming a part cylindrical axis.
35. The joint in accordance with claim 34, wherein a plane containing the part cylindrical axes of the surfaces of the mobile part and the supporting part contain contact lines of the mobile part and the supporting part with the guiding and connecting part.
36. The joint in accordance with claim 31, wherein the guiding and connecting part has a thickness selected in the range of 0.02 μm to 5 cm; and/or wherein the guiding and connecting part has a bending elasticity which is at least twice the bending elasticity of the mobile part and/or of the supporting part; and/or wherein the guiding and connecting part, the mobile part and the supporting part are made from the same material; and/or wherein the guiding and connecting part, the mobile part and the supporting part are made in one piece.
37. The joint in accordance with claim 31, wherein the guiding and connecting part, the mobile part and the supporting part are separate components.
38. The joint in accordance with claim 31, wherein the mobile part can rotate relative to the supporting part, with a range of rotation being selected in the range of 20 to 160°.
39. The joint in accordance with claim 31, wherein the mobile part comprises a material selected from the group of members consisting of metal, such as stainless steel, steel, aluminium, aluminium alloys, non-ferrous alloys, high temperature alloys, carbon steels, high carbon steels, steel alloys, aluminium bronze, nickel, nickel alloys, brass, oxygen-free copper, titanium, niobium, molybdenum, tantalum, plastic, such as, polyether ether ketone, polycarbonate, polyoxymethylene, polytetrafluoroethylene, vespel polyimide, glass, wood, ceramic material, silicon and combinations of the foregoing; and/or wherein the supporting part comprises a material selected from the group of members consisting of metal, such as stainless steel, steel, aluminium, aluminium alloys, non-ferrous alloys, high temperature alloys, carbon steels, high carbon steels, steel alloys, aluminium bronze, nickel, nickel alloys, brass, oxygen-free copper, titanium, niobium, molybdenum, tantalum, plastic, such as, polyether ether ketone, polycarbonate, polyoxymethylene, polytetrafluoroethylene, vespel polyimide, glass, wood, ceramic material, silicon and combinations of the foregoing; and/or wherein the guiding and connecting part comprises a material selected from the group of members consisting of stainless steel, steel, aluminium, aluminium alloys, non-ferrous alloys, high temperature alloys, carbon steels, high carbon steels, steel alloys, aluminium bronze, nickel, nickel alloys, brass, oxygen-free copper, titanium, niobium, molybdenum, tantalum, polyether ether ketone, polycarbonate, polyoxymethylene, polytetrafluoroethylene, vespel polyimide, silicon and combinations of the foregoing.
40. The joint in accordance with claim 31, wherein a thickness of the mobile part is selected in the range of 0.04 μm to 100 cm; and/or wherein a thickness of the supporting part is selected in the range of 0.04 μm to 100 cm.
41. The joint in accordance with claim 31, wherein the guiding and connecting part is fastened to at least one of the mobile part and the supporting part.
42. The joint in accordance with claim 31, wherein one or more ends of the guiding and connecting part is fastened to at least one of the mobile part and the supporting part.
43. The joint in accordance with claim 31, wherein one or more ends of the guiding and connecting part is fastened to at least one of the mobile part and the supporting part and wherein the guiding and connecting part is fastened to at least one of the mobile part and the supporting part by at least one of spot welding, welding, soldering, brazing, screwing, bonding and riveting.
44. A mechanism for moving a device in vacuum, the mechanism comprising a plurality of joints, each of the joints comprising a supporting part, a mobile part and a guiding und connecting part, wherein the mobile part and the supporting part each have at least a region of convex shape, with the regions of convex shape of the mobile part and of the supporting part facing one another and with the guiding and connecting part being arranged, between the regions of convex shape, wherein the guiding and connecting part has a greater bending elasticity than either of the supporting part and the mobile part and the guiding and connecting part has a reduced thickness in comparison to the supporting part and the mobile part, and wherein the mobile part can move relative to the supporting part.
45. The mechanism in accordance with claim 44, wherein the mechanism comprises four joints.
46. The mechanism in accordance with claim 44, wherein the mechanism is a parallelogram mechanism with one side of the parallelogram mechanism being held fixed to a further component and the plurality of joints being arranged at the edges of the parallelogram mechanism.
47. The mechanism in accordance with claim 46, wherein the parallelogram mechanism is configured to be moved to and fro in one direction relative to the one side of the parallelogram mechanism held fixed to the further component.
48. A device comprising a plurality of joints, each of the joints comprising a supporting part, a mobile part and a guiding und connecting part, wherein the mobile part and the supporting part each have at least a region of convex shape, with the regions of convex shape of the mobile part and of the supporting part facing one another and with the guiding and connecting part being arranged, between the regions of convex shape, wherein the guiding and connecting part has a greater bending elasticity than either of the supporting part and the mobile part and the guiding and connecting part has a reduced thickness in comparison to the supporting part and the mobile part, and wherein the mobile part can move relative to the supporting part, the device being configured to be moved in a vacuum.
49. The device in accordance with claim 48, further comprising an actuation mechanism, with the actuation mechanism being attached at the side of the mechanism held fixed to a further component.
50. The device in accordance with claim 49, wherein the actuation mechanism comprises a push rod.
51. The device in accordance with claim 48, further comprising a support for linking the device to an applicator attached to a further side of the mechanism of the device remote from the side held fixed to a further component.
52. The device in accordance with claim 51, wherein the support comprises at least one of a bracket, a fork, a plate, a holder, a table and a combination of the foregoing.
53. The device in accordance with claim 51, wherein the support is configured to make contact to the applicator in a direction perpendicular to the direction of movement.
54. The device in accordance with claim 51, wherein the applicator comprises one of a source holder for a source, an aperture, a source, a beam dump, a deflector and combinations of the foregoing.
Description
[0036] The invention will now be described in further detail by way of example only with reference to the accompanying drawings. In the drawings there are shown:
[0037]
[0038]
[0039]
[0040]
[0041]
[0042]
[0043]
[0044]
[0045]
[0046]
[0047]
[0048]
[0049]
[0050]
[0051]
[0052] The guiding and connecting part 16 has a greater bending elasticity than either of the supporting part 12 and the mobile part 14 and the guiding and connecting part 16 has a reduced thickness in comparison to the supporting part 12 and the mobile part 14, and wherein the mobile part 14 can move relative to the supporting part 12.
[0053] The respective region 18, 20 of convex shape of at least one of the mobile part 14 and the supporting part 12 is formed by a part cylindrical surface 22, 24 having an arcuate shape. The rounded surface of the part cylindrical surfaces 22, 24 permit a rotation of the mobile part 14 relative to the supporting part 12 about a part cylindrical axis. The surface normal of the part cylindrical surfaces 22, 24 provides a support in the direction of the length of the respective part cylindrical surface 22, 24, i.e. in the axial direction of the part cylinder, so that the mobile part 14 rotates relative to the supporting part 12 and is at the same time axially supported.
[0054] In this connection it should be noted that a plane P containing the part cylindrical axes of the part cylindrical surfaces 22, 24 of the mobile part 14 and the supporting part 12 contain contact lines of the mobile part 14 and of the supporting part 12 with the guiding and connecting part 16.
[0055] On forming a joint the respective region 18, 20 of convex shape of the mobile part 14 and of the supporting part 12 is formed by bending a respective first part of the region 18, 20 of convex shape relative to a second part of the region 18, 20 of convex shape, with the bend being selected in the range of 10 to 80°. In this way the mobile part 14 can rotate by between 20 and 160° relative to the supporting part 12.
[0056]
[0057] The top drawing shows a first position of movement of the mechanism 40 in which it is deflected upwardly, the middle drawing shows the mechanism 40 in its rest state, whereas the bottom drawing shows the mechanism deflected downwardly.
[0058] The mechanism comprises four sides 42, 44, 46, 48 with the first side 42 (i.e. the right side) being connected to a further component 50 held fixed in position and third side 46 disposed opposite the first side 42 to which a further component (not shown in
[0059] The plurality of joints 10 are arranged at edges 52, 54, 56, 58 of the mechanism 40. One of the supporting parts 12 of the four joints 10 of the mechanism 40 is formed at the side 42 fixed to a further component 50. A further one of the supporting part 12 of the four joints 10 of the mechanism 40 is formed at the side 46 configured to be connected to the support 106 (see
[0060] The mobile parts 14 of the respective joints 10 can hence move relative to both the further component 50 and the support 106. The parallelogram mechanism 40 is configured to be moved to and fro in one direction A relative to the one side 42 of the parallelogram mechanism 40 held fixed to the further component 50.
[0061] The individual joint 10 (
[0062] The cylindrical surfaces 22, 24 of the top and bottom parts 14, 12 facing the guiding and connecting part 16 define the range of rotation, in the present example both bends are 30°, resulting in a total range of rotation of at most 60°. The plane containing the cylinder axes of these surfaces 22, 24 also contains both contact lines of the upper and lower parts 14, 12 with the elastic sheet 16 (
[0063] Approximately halfway between these contact lines is the momentary axis of rotation between the upper and lower parts 12, 14. During rotation, this rotation axis moves along the surface approximately halfway between the upper and lower surfaces of the elastic material, i.e. of the guiding and connecting part 16, and collinear with the axes of the cylindrical surfaces 22, 24. As an example for a small mechanism 40, the upper and lower parts 14, 12 may consist of stainless steel sheet metal 1 mm thick, the elastic sheet may have a thickness of 20 μm.
[0064] For a given position during the movement, the shaded rectangles 50 in
[0065] For the lower part 12, these originate in the lower left quadrant, directed at the end line of the contact surface between the lower part 12 and the elastic sheet 16. The mechanism 40 only works as intended if the force directions remain in these quadrants at all times throughout the movements. For many cases, such as the parallelogram mechanism 40 shown in
[0066] The joint 10 of
[0067] Preferentially, and as shown by the positions in
[0068] If operated near or beyond these points, the elastic sheet 16 may be bent sharply near its fastening points, and may eventually fail. Forces pointing towards the contact point in the lower right quadrant for the upper part and in the upper left quadrant for the lower part in
[0069] Finally, for both of the two cases discussed above, if the direction of the forces is reversed, the elastic sheet 16 will be compressively strained in plane, leading to bulging, crumpling and failure for already rather small forces.
[0070] For a joint 10 that needs to support forces in these directions, the attachment of the elastic sheet may be reversed as shown in
[0071]
[0072] As indicated by the arrows in
[0073] In a complex mechanism 40 containing several joints 10, such as shown in
[0074] As further indicated in
[0075] The guiding and connecting part 16 is arranged between the respective regions of convex shape 18, 20, with a first border 32′ of the region 20 of convex shape of the supporting part coinciding with the end 30 of the supporting part 12, and a second border 32 of the region 20 of convex shape of the supporting part 12 being arranged symmetrically about the apex of the region 20 of convex shape with respect to the first border 32′ such that the region 20 of convex shape extends between the first and second borders 32′, 32, with its apex lying at least substantially equidistantly between the first and second borders 32′, 32.
[0076] The same is true with respect to first and second borders 36′, 36 of the region 18 of convex shape of the mobile part 14, i.e. the end 34 of the mobile part coincides with the first border 36′ of the region 18 of convex shape of the mobile part 14.
[0077] In contrast to this in the joint 10 of
[0078] The cylindrically bent surfaces 22, 24 of the upper and lower parts 14, 12 in contact with the elastic sheet 16 do not necessarily need to have a constant radius. A constant and identical radius for both surfaces 22, 24, however, is favorable since it leads to a constant maximum value for the elastic bending of the sheet 16 in both directions symmetric to its flat state.
[0079] The elastic sheet 16 wears due to internal friction and eventually crack formation leading to the rupture of the sheet 16. The sheet 16 should therefore preferably have smooth and rounded edges to hinder the nucleation of fatigue cracks at the edges. It should also vary only gradually, or not at all, in cross-section as cracks also tend to form at the points of largest cross-sectional change.
[0080] Most importantly, however, the radius of the cylindrical surfaces 22, 24 should be as large as possible for the given spatial constraints, and in relation to the sheet thickness. A larger radius leads to smaller bending, less internal friction, and thereby extends the lifetime of the mechanism. The cylindrical surfaces 22, 24 in contact with the elastic sheet 16 should also be as smooth as possible.
[0081] In this connection it should be noted that when reference is made to an elastic sheet 16, this means that the sheet 16 is more elastic in its bending properties than the respective supporting part 12 and mobile part 14.
[0082] In particular, the cylindrical surfaces 22, 24 should have as few as possible and preferably no localized protrusions or recesses that may cause uneven operation and might indent and damage the sheet 16.
[0083] In this connection it should further be noted that the guiding and connecting part 16 preferably has a bending elasticity which is at least twice the bending elasticity of the mobile part 14 and/or of the supporting part 12. However, the elasticity of the guiding and connecting part should not be so low, that this deforms when it contacts the mobile part 14 and the supporting part 12 respectively.
[0084] In this connection it should be noted that the guiding and connecting part 16, the mobile part 14 and the supporting part 12 are made from the same material, alternatively the guiding and connecting part 16 can be made from a different material as the mobile part 14 and the supporting part 12, it is also possible that all three of the guiding and connecting part 16, the mobile part 14 and the supporting part are each made from different materials, with each material being suited to its specific function. Since the guiding and connecting part 16 is required to have a bending elasticity it is favourable if this is made from a material typically employed for springs, such as spring metal.
[0085] The load limits of the joint 10 are given by the cross-section of the used elastic sheet 16 and the mechanical strength of the used elastic sheet 16. For a given strength, a lengthening of the sheet 16 normal to the image plane of the figures is preferred over using a thicker sheet, as the wear of the sheet 16 strongly increases with thickness for a given bend radius. The width of the sheet 16 also defines the ability of the mechanism 40 to provide lateral guidance, in the out-of-plane direction normal to the plane in which the movement takes place. The wider the sheet 16, the larger the lateral forces it can support. The width of the sheet 16 finds its limits in the available space, but also in the manufacturing tolerances of the parts, as deviations from the cylindrical shape of the surfaces 22, 24 in contact with the sheet 16 may strain the sheet 16, both locally and globally. One also has to take into account possible dynamical deformations of the upper and lower parts 12, 14 under heavy loads, leading to the same problem, however depending on the load during operation.
[0086] The guiding and connecting part 16, the mobile part 14 and the supporting part 12 shown in the foregoing are made from separate components that are connected to one another.
[0087] In the following an example of integrally formed joints 10 will be discussed in connection with
[0088]
[0089] The drawings also suggest that one may fabricate the entire joint 10 from one single piece of material by cutting along the solid lines. While solving the problem of even attachment of the elastic sheet 16, this has also disadvantages. In particular, the cut surfaces between the sheet 16 and the upper and lower bent surfaces 22, 24 may not be smooth enough to allow for an evenly distributed pressure normal to the sheet 16, and facilitate the nucleation and propagation of cracks. In addition, the upper and lower parts 12, 14 of the joint 10 should be rigid, whereas the sheet 16 should be elastic. Cutting the parts 12, 14, 16 from the same material, this stiffness difference may be generated mostly by varying the relative thickness of the parts 12, 14, 16, which offers only a limited range of optimization. For ultra-small mechanisms 40 such as in micromechanics, however, this may be a way to go.
[0090]
[0091] The parallelogram mechanism 40 based on the joints 10 according to the invention is shown in
[0092] The device 100 comprises an actuation mechanism 102, with the actuation mechanism 102 being attached at the side 42 of the mechanism 40 held fixed to a further component 50. Specifically some of the supporting parts 12 of the joints 10 of the mechanism 40 are connected to the actuation mechanism 102.
[0093] The actuation mechanism 102 comprises a push rod 104. The push rod 104 in use pushes the mechanism 40 to the left and the right in the drawing of
[0094] The side 46 of the mechanism 40 is connected to a support 106 for linking the device 100 to an applicator 108 (see
[0095] The support 106 shown in
[0096] Generally speaking the support 106 is configured to make contact to the applicator 108 in a direction perpendicular B to the direction A of movement, i.e. in a manner similar to a fork lift truck.
[0097]
[0098] It should generally be noted that the guiding and connecting part 16 can have a thickness selected in the range of 0.02 82 m to 5 cm, in particular 1 to 100 μm. It should further generally be noted that a thickness of the mobile part 14 can be selected in the range of 0.04 μm to 100 cm, in particular in the range of 0.5 to 2 mm. It should further generally be noted that a thickness of the supporting part 12 can be selected in the range of 0.04 μm to 100 cm, in particular in the range of 0.5 to 2 mm.
[0099] The mobile part 14 may comprise, i.e. be made of, a material selected from the group of members consisting of metal, such as stainless steel, steel, aluminium, aluminium alloys, non-ferrous alloys, high temperature alloys, carbon steels, high carbon steels, steel alloys, aluminium bronze, nickel, nickel alloys, brass, oxygen-free copper, titanium, niobium, molybdenum, tantalum, plastic, such as, polyether ether ketone (PEEK), polycarbonate (PO), polyoxymethylene (POM), polytetrafluoroethylene (PTFE), vespel polyimide, glass, wood, ceramic material, silicon and combinations of the foregoing.
[0100] The supporting part 12 may comprise, i.e. be made of, a material selected from the group of members consisting of metal, such as stainless steel, steel, aluminium, aluminium alloys, non-ferrous alloys, high temperature alloys, carbon steels, high carbon steels, steel alloys, aluminium bronze, nickel, nickel alloys, brass, oxygen-free copper, titanium, niobium, molybdenum, tantalum, plastic, such as, polyether ether ketone (PEEK), polycarbonate (PO), polyoxymethylene (POM), polytetrafluoroethylene (PTFE), vespel polyimide, glass, wood, ceramic material, silicon and combinations of the foregoing.
[0101] The guiding and connecting part 16 may comprise, i.e. be made of, a material selected from the group of members consisting of stainless steel, steel, aluminium, aluminium alloys, non-ferrous alloys, high temperature alloys, carbon steels, high carbon steels, steel alloys, aluminium bronze, nickel, nickel alloys, brass, oxygen-free copper, titanium, niobium, molybdenum, tantalum, polyether ether ketone (PEEK), polycarbonate (PO), polyoxymethylene (POM), polytetrafluoroethylene (PTFE), vespel polyimide, silicon and combinations of the foregoing.
[0102] The practical implementation of the mechanism 40 in a device 100 is shown in
LIST OF REFERENCE NUMERALS
[0103] 10 joint [0104] 12 supporting part [0105] 14 mobile part [0106] 16 guiding and connecting part [0107] 18 region of convex shape [0108] 20 region of convex shape [0109] 22 surface [0110] 24 surface [0111] 26 first end of 16 [0112] 28 second end of 16 [0113] 30 end of 12 [0114] 32, 32′ second border of 20, first border of 20 [0115] 34 end of 14 [0116] 36, 36′ second border of 18, first border of 18 [0117] 40 mechanism [0118] 42 first side [0119] 44 second side [0120] 46 third side [0121] 48 fourth side [0122] 50 further component [0123] 52 edge [0124] 54 edge [0125] 56 edge [0126] 58 edge [0127] 100 device [0128] 102 actuation mechanism [0129] 104 push rod [0130] 106 support [0131] 108 applicator [0132] 110 source [0133] 112 source holder [0134] 114 aperture [0135] 116 beam dump [0136] 118 deflector [0137] A direction [0138] B direction perpendicular to A [0139] P plane containing axes