Electric tilting and continuously rotating objective table
By combining a central bearing hub, ball bearings, and wedge rings, the problem of achieving continuous rotation and precise tilting of the stage within a small package was solved, simplifying the drive mechanism and reducing costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-04
- Publication Date
- 2026-03-03
AI Technical Summary
Existing stages struggle to combine continuous rotation range and precise tilt within a small package, and existing solutions increase design complexity, cost, and size.
The mechanism design, which combines a central bearing hub, ball bearings, wedge rings, and actuators, allows the stage to achieve precise tilting motion of ±3° and continuous rotation of 360° in any direction. The tilting and rotation of the top plate are achieved through the cooperation of the ball transmission unit and the wedge ring.
It achieves a combination of continuous rotation range and precise tilt within a small package, simplifying the drive mechanism and reducing design complexity and cost.
Smart Images
Figure CN121594291A_ABST
Abstract
Description
Technical Field
[0001] The present invention generally relates to a positioning stage, and more specifically, to an electrically tilting and continuously rotating stage. Background Technology
[0002] There is currently a market demand for stages that integrate pitch and yaw motion to fill a gap in existing products. The required stage must offer a continuous range of rotation while allowing precise tilt adjustment. For example, the requirements for this stage include integrating the drive and control systems within a 115mm × 115mm package. Currently, no manufacturer has achieved this with a stage featuring dual rotation axes. This structure, achieving an unrestricted positioning range within a relatively small form factor, can support a wide range of applications in photonics and many other industries. In particular, when combined with XY and / or Z linear stages, up to five axes of motion can be achieved within the same 115mm × 115mm area.
[0003] Most available pitch and yaw stages have a standard range of motion between 2 and 3 degrees. Increasing this range is difficult due to the relationship between the two rotation axes and the drive mechanisms. Typically, a large movement on one axis requires the drive system of the second axis to follow that movement. This means any electrical connections need to use slip rings or similar devices, increasing design complexity, cost, and size. Another alternative is to combine the pitch stage with an additional rotation stage, but this always has a negative impact on performance depending on the stacking order of the stages. Either the rotation range is limited due to the trailing cables, or the lateral displacement of the top platform is increased due to the increased distance from the center of the tilt axis. In addition, there is the cost of purchasing two stages and the complexity of the control system for synchronizing their movements.
[0004] Therefore, there has long been a need for pitch and yaw stage that can overcome the aforementioned shortcomings of existing products. Summary of the Invention
[0005] The main difference between this disclosure and the prior art is that it allows for precise tilt adjustment while permitting a continuous range of rotation. This disclosure proposes a pitch and yaw stage capable of achieving precise tilting motion of ±3° in any direction and continuous rotation of 360°.
[0006] One embodiment of this disclosure provides a tilting and continuously rotating stage, comprising: a central axis defining a main axis of rotation of the stage; a bearing hub rotatable about the central axis; a top plate; a pair of ball bearings mounted on the bearing hub defining a tilting axis of the top plate; a preload element configured to press the top plate against the pair of ball bearings; a pair of ball transfer units mounted on opposite sides of the bottom surface of the top plate perpendicular to the tilting axis; a rotatable wedge ring concentrically mounted to the bearing hub, the wedge ring having a top surface angled relative to the top plate and providing an operating surface for the pair of ball transfer units; a first actuator configured to rotate the bearing hub about the main axis; and a second actuator configured to rotate the wedge ring about the main axis; wherein rotational motion applied to the wedge ring causes the pair of ball transfer units to move upward or downward on the top surface of the wedge ring, thereby causing the top plate to tilt about the tilting axis. Attached Figure Description
[0007] Figure 1 This is a transparent perspective view of an electrically tilting and continuously rotating stage according to one embodiment.
[0008] Figure 2 This is a perspective view of an electrically tilting and continuously rotating stage according to one embodiment.
[0009] Figure 3 This is a cross-sectional view of an electrically tilting and continuously rotating stage according to one embodiment.
[0010] Figure 4 This is a truncated perspective view of an electrically tilting and continuously rotating stage according to one embodiment.
[0011] Figure 5 This is another sectional perspective view of an electrically tilting and continuously rotating stage according to one embodiment.
[0012] Figure 6 This is a perspective view of a tilted ring according to one embodiment.
[0013] Figure 7 This is a front view of a tilted ring according to one embodiment.
[0014] Figure 8 This illustrates how two cam followers are positioned on a tilting ring according to one embodiment.
[0015] Figure 9 The stage is shown in a 0° tilt state according to one embodiment.
[0016] Figure 10 The stage is shown in a 3° tilt state according to one embodiment.
[0017] Figure 11The stage is shown in a -3° tilt state according to one embodiment. Detailed Implementation
[0018] The exemplary embodiments described according to the principles of this disclosure are intended to be understood in conjunction with the accompanying drawings, which should be considered an integral part of the entire written description. In the description of embodiments of this disclosure herein, any reference to direction or orientation is for ease of description only and does not limit the scope of this disclosure in any way. Related terms such as “below,” “above,” “horizontal,” “vertical,” “above,” “below,” “up,” “bottom,” and their derivatives (e.g., “horizontally,” “downward,” “upward,” etc.) should be understood to refer to the orientation described at the time or shown in the drawings under discussion. Unless explicitly stated otherwise, these related terms are for ease of description only and do not require the device to be constructed or operated in a particular orientation. Unless explicitly stated otherwise, terms such as “attach,” “adhere,” “connect,” “couple,” and “interconnected” refer to a relationship in which structures are directly or indirectly fixed or attached to each other through intermediate structures, and a relationship in which structures are movably or rigidly attached or associated. Furthermore, the features and advantages of this disclosure are explained with reference to exemplary embodiments. Therefore, this disclosure should not be explicitly limited to exemplary embodiments of possible non-limiting combinations of features, which may exist alone or in combination with other features; the scope of this disclosure should be defined by the appended claims.
[0019] This disclosure describes the best mode of carrying out this disclosure as currently contemplated. This description should not be construed as limiting the disclosure, but rather as providing examples of the disclosure for illustrative purposes only with reference to the accompanying drawings to explain the advantages and construction of the disclosure to those skilled in the art. In various perspectives of the drawings, the same reference numerals denote similar or analogous parts.
[0020] It is particularly important to note that the disclosed embodiments are merely a few examples of the many advantageous uses of the inventive teachings herein. Generally, the statements in this specification do not necessarily limit any of the claimed disclosures. Furthermore, some statements may apply only to certain inventive features but not to others. Generally, unless otherwise stated, elements in the singular form may be in the plural form, and vice versa, without loss of generality.
[0021] The novelty and inventiveness of this disclosure lie in the relationship between the two rotational axes and the central mechanism. The basic principle of the tilting mechanism includes a movable world 104 located on a fixed horizontal axis 112 in the pitch direction. Figure 1In the example shown, this axis can be implemented by a pair of ball bearings 106 with springs 113 or a magnetic preload device. For applications with higher loads and different operating directions (i.e., vertical or inverted), a physical axis can be used. This constrains the mobile world in five degrees of freedom (translation in the X, Y, and Z directions and rotation about the X and Z axes). Below the mobile world is a rotating wheel with a tilted top surface. This tilted surface acts as the operating surface for a pair of cam followers fixed to the bottom surface of the mobile world. As the wheel rotates, the cam followers (in this example, a pair of ball transfer units (BTUs) or ball bearings 103) move up and down on either side of the tilted surface, tilting the mobile world about a fixed pitch direction horizontal axis. This restricts the final degree of freedom of rotation about the Y-axis.
[0022] This tilting mechanism can be used independently; it can be manually operated or driven as needed, or it can be used in conjunction with the second rotating mechanism shown below.
[0023] In this context, an example application of this disclosure is a pitch and yaw stage capable of precise tilting motion of ±3° in any direction and continuous 360° rotation. These two movements can be performed independently or simultaneously, depending on application requirements. Figure 2 In one embodiment shown, the stage body measures 115mm wide × 115mm deep × 57mm high, and includes a diameter It is a 100mm circular moving platform.
[0024] In one embodiment, such as Figures 3 to 5 As shown, the stage mechanism includes the following components:
[0025] a) First is the central short axis 101, which coaxially positions the mechanism inside the stage housing and serves as the main axis of rotation 111 of the stage.
[0026] b) Next is the main bearing hub 102, which rotates about a central short axis via a pair of back-to-back angular contact bearings. This main bearing hub serves as the main rotation point of the stage.
[0027] c) A pair of ball bearings 103 mounted on the main bearing hub serve as the tilting axis 112 of the top plate 104, located in corresponding chamfered holes and slots. A set of tension springs 113 then provides preload to hold the top plate against the ball bearings. This constrains the top plate in three translational degrees of freedom (X, Y, Z) and one rotational degree of freedom (Y).
[0028] d) The next component is a rotatable wedge ring 105, coaxially mounted on the main bearing hub, which is allowed to rotate independently. The inclined top surface 110 of the wedge ring 105 provides an operating surface for a pair of ball transfer units (BTUs) 106 that act as cam followers. These BTUs are fixed to opposite sides of the bottom surface of the top plate in a manner perpendicular to the inclined axis. The combination of the wedge ring and the BTUs constrains the top plate in an additional rotational degree of freedom (X). Any rotational movement applied to the wedge ring will cause the BTUs to move up or down on the top surface of the wedge ring, which in turn causes the top plate to tilt about the fixed inclined axis.
[0029] e) The final components are two worm gears, worm gear 107 and worm gear 108, which are mounted on the main bearing hub 102 and the rotating wedge ring 105. When assembled with a pair of worm shafts 109, these components provide final constraint on the rotation of the main bearing hub and the wedge ring about the Z-axis. The system allows the two worm gears to be driven independently or synchronously according to the desired motion.
[0030] In one embodiment, the wedge ring includes a tilting ring mounted on a rotatable disk. Using a tilting ring can reduce the weight of the wedge ring and simplify its manufacturing process. Figure 6 and Figure 7 These are the 3D view and the front view of the tilted ring, respectively. Figure 8 This illustrates how the first and second cam followers are positioned on the top surface of the tilting ring. As the cam followers move up and down along the top surface of the tilting ring, the tilt angle changes accordingly. Figure 9 The diagram shows the 0° tilt state when the first cam follower and the second cam follower are at the same height at the midpoint of opposite sides of the tilt ring. Figure 10 The diagram shows a 30° tilt state when the first cam follower is at the high point of the tilt ring and the second cam follower is at the low point of the tilt ring. Figure 11 The diagram shows a -3° tilt when the first cam follower is at the low point of the tilting ring and the second cam follower is at the high point of the tilting ring. The operating principle of the tilting mechanism described above also applies to... Figure 1 The solid wedge ring 105 shown.
[0031] In view of the foregoing, one embodiment of this disclosure provides the desired stage, which has the unique advantage of providing a continuous range of rotation while still allowing precise adjustment of the tilt.
[0032] While this disclosure has described several embodiments with considerable detail and specificity, it is not limited to any such details or embodiments or any particular embodiment, but should be interpreted with reference to the appended claims in order to provide the broadest possible interpretation of these claims in accordance with the prior art, and thus effectively include the intended scope of this disclosure.
Claims
1. A tilting and continuously rotating stage, comprising: The central axis defines the main axis of rotation of the stage; The bearing hub is capable of rotating about the central axis; roof; A pair of ball bearings are mounted on a bearing hub, the pair of ball bearings defining the tilt axis of the top plate; A preload element is configured to press the top plate against the pair of ball bearings; A pair of ball transfer units are mounted on opposite sides of the bottom surface of the top plate in a manner perpendicular to the inclined axis; A rotatable wedge ring is coaxially mounted to a bearing hub. The wedge ring has a top surface that is angled relative to the top plate and provides an operating surface for the pair of ball transmission units. The first actuator is configured to cause the bearing hub to rotate about the main axis; and A second actuator is configured to cause the wedge to rotate about the main axis; The rotational motion applied to the wedge ring causes the ball transmission unit to move up or down on the top surface of the wedge ring, and the upward or downward movement in turn causes the top plate to tilt about the inclined axis.
2. The tilting and continuously rotating stage according to claim 1, wherein, The first actuator includes a first worm gear mounted on the bearing hub and a first worm shaft meshing with the first worm gear; the second actuator includes a second worm gear mounted on the wedge ring and a second worm shaft meshing with the second worm gear.
3. The tilting and continuously rotating stage according to claim 1, wherein, The first actuator and the second actuator are configured to rotate the bearing hub and the wedge ring independently or synchronously.
4. The tilting and continuously rotating stage according to claim 1, wherein, The stage is configured to provide a precise tilting motion of ±3° in any direction and to achieve continuous 360° rotation around the main axis.
5. The tilting and continuously rotating stage according to claim 1, wherein, The rotatable wedge ring includes an inclined ring mounted on a rotatable disk, and the top surface of the inclined ring is configured to provide the running surface for the pair of ball transfer units.